Bernecker, Katharina; Job, Veronika
2015-01-01
Research suggests that beliefs about willpower affect self-regulation following previous self-regulatory demands (Job et al., 2010). Some people believe that their willpower is limited, meaning that after a demanding task it needs to be replenished (limited theory). By contrast, others believe that willpower is not limited and that previous self-control tasks even activate willpower (non-limited theory). We hypothesized that when people experience a demanding day their beliefs about willpower predict their expected capacity to self-regulate and their actual self-regulation on the following day. In a daily diary study (N = 157), we measured students’ daily level of demands, their expected performance in unpleasant tasks, and their effective goal striving. Results showed that following a demanding day, students with a non-limited theory had higher expectations about their progress in unpleasant tasks and were striving more efficiently for their goals than students with a limited theory. These findings suggest that beliefs about willpower affect whether demands experienced on a previous day have positive or negative consequences on people’s self-regulation. PMID:26528198
Design of limited-stop service based on the degree of unbalance of passenger demand
2018-01-01
This paper presents a limited-stop service for a bus fleet to meet the unbalanced demand of passengers on a bus route and to improve the transit service of the bus route. This strategy includes two parts: a degree assessment of unbalanced passenger demand and an optimization of the limited-stop service. The degree assessment of unbalanced passenger demand, which is based on the different passenger demand between stations and the unbalance of passengers within the station, is used to judge whether implementing the limited-stop service is necessary for a bus route. The optimization of limited-stop service considers the influence of stop skipping action and bus capacity on the left-over passengers to determine the proper skipping stations for the bus fleet serving the entire route by minimizing both the waiting time and in-vehicle time of passengers and the running time of vehicles. A solution algorithm based on genetic algorithm is also presented to evaluate the degree of unbalanced passenger demand and optimize the limited-stop scheme. Then, the proper strategy is tested on a bus route in Changchun city of China. The threshold of degree assessment of unbalanced passenger demand can be calibrated and adapted to different passenger demands. PMID:29505585
Design of limited-stop service based on the degree of unbalance of passenger demand.
Zhang, Hu; Zhao, Shuzhi; Liu, Huasheng; Liang, Shidong
2018-01-01
This paper presents a limited-stop service for a bus fleet to meet the unbalanced demand of passengers on a bus route and to improve the transit service of the bus route. This strategy includes two parts: a degree assessment of unbalanced passenger demand and an optimization of the limited-stop service. The degree assessment of unbalanced passenger demand, which is based on the different passenger demand between stations and the unbalance of passengers within the station, is used to judge whether implementing the limited-stop service is necessary for a bus route. The optimization of limited-stop service considers the influence of stop skipping action and bus capacity on the left-over passengers to determine the proper skipping stations for the bus fleet serving the entire route by minimizing both the waiting time and in-vehicle time of passengers and the running time of vehicles. A solution algorithm based on genetic algorithm is also presented to evaluate the degree of unbalanced passenger demand and optimize the limited-stop scheme. Then, the proper strategy is tested on a bus route in Changchun city of China. The threshold of degree assessment of unbalanced passenger demand can be calibrated and adapted to different passenger demands.
Diagnosing phosphorus limitations in natural terrestrial ecosystems in carbon cycle models
NASA Astrophysics Data System (ADS)
Sun, Yan; Peng, Shushi; Goll, Daniel S.; Ciais, Philippe; Guenet, Bertrand; Guimberteau, Matthieu; Hinsinger, Philippe; Janssens, Ivan A.; Peñuelas, Josep; Piao, Shilong; Poulter, Benjamin; Violette, Aurélie; Yang, Xiaojuan; Yin, Yi; Zeng, Hui
2017-07-01
Most of the Earth System Models (ESMs) project increases in net primary productivity (NPP) and terrestrial carbon (C) storage during the 21st century. Despite empirical evidence that limited availability of phosphorus (P) may limit the response of NPP to increasing atmospheric CO2, none of the ESMs used in the previous Intergovernmental Panel on Climate Change assessment accounted for P limitation. We diagnosed from ESM simulations the amount of P need to support increases in carbon uptake by natural ecosystems using two approaches: the demand derived from (1) changes in C stocks and (2) changes in NPP. The C stock-based additional P demand was estimated to range between -31 and 193 Tg P and between -89 and 262 Tg P for Representative Concentration Pathway (RCP) 2.6 and RCP8.5, respectively, with negative values indicating a P surplus. The NPP-based demand, which takes ecosystem P recycling into account, results in a significantly higher P demand of 648-1606 Tg P for RCP2.6 and 924-2110 Tg P for RCP8.5. We found that the P demand is sensitive to the turnover of P in decomposing plant material, explaining the large differences between the NPP-based demand and C stock-based demand. The discrepancy between diagnosed P demand and actual P availability (potential P deficit) depends mainly on the assumptions about availability of the different soil P forms. Overall, future P limitation strongly depends on both soil P availability and P recycling on ecosystem scale.
Diagnosing phosphorus limitations in natural terrestrial ecosystems in carbon cycle models.
Sun, Yan; Peng, Shushi; Goll, Daniel S; Ciais, Philippe; Guenet, Bertrand; Guimberteau, Matthieu; Hinsinger, Philippe; Janssens, Ivan A; Peñuelas, Josep; Piao, Shilong; Poulter, Benjamin; Violette, Aurélie; Yang, Xiaojuan; Yin, Yi; Zeng, Hui
2017-07-01
Most of the Earth System Models (ESMs) project increases in net primary productivity (NPP) and terrestrial carbon (C) storage during the 21st century. Despite empirical evidence that limited availability of phosphorus (P) may limit the response of NPP to increasing atmospheric CO 2 , none of the ESMs used in the previous Intergovernmental Panel on Climate Change assessment accounted for P limitation. We diagnosed from ESM simulations the amount of P need to support increases in carbon uptake by natural ecosystems using two approaches: the demand derived from (1) changes in C stocks and (2) changes in NPP. The C stock-based additional P demand was estimated to range between -31 and 193 Tg P and between -89 and 262 Tg P for Representative Concentration Pathway (RCP) 2.6 and RCP8.5, respectively, with negative values indicating a P surplus. The NPP-based demand, which takes ecosystem P recycling into account, results in a significantly higher P demand of 648-1606 Tg P for RCP2.6 and 924-2110 Tg P for RCP8.5. We found that the P demand is sensitive to the turnover of P in decomposing plant material, explaining the large differences between the NPP-based demand and C stock-based demand. The discrepancy between diagnosed P demand and actual P availability (potential P deficit) depends mainly on the assumptions about availability of the different soil P forms. Overall, future P limitation strongly depends on both soil P availability and P recycling on ecosystem scale.
Demand forecasting of electricity in Indonesia with limited historical data
NASA Astrophysics Data System (ADS)
Dwi Kartikasari, Mujiati; Rohmad Prayogi, Arif
2018-03-01
Demand forecasting of electricity is an important activity for electrical agents to know the description of electricity demand in future. Prediction of demand electricity can be done using time series models. In this paper, double moving average model, Holt’s exponential smoothing model, and grey model GM(1,1) are used to predict electricity demand in Indonesia under the condition of limited historical data. The result shows that grey model GM(1,1) has the smallest value of MAE (mean absolute error), MSE (mean squared error), and MAPE (mean absolute percentage error).
Diagnosing phosphorus limitations in natural terrestrial ecosystems in carbon cycle models
Sun, Yan; Peng, Shushi; Goll, Daniel S.; ...
2017-04-28
Most of the Earth System Models (ESMs) project increases in net primary productivity (NPP) and terrestrial carbon (C) storage during the 21st century. Despite empirical evidence that limited availability of phosphorus (P) may limit the response of NPP to increasing atmospheric CO 2, none of the ESMs used in the previous Intergovernmental Panel on Climate Change assessment accounted for P limitation. We diagnosed from ESM simulations the amount of P need to support increases in carbon uptake by natural ecosystems using two approaches: the demand derived from changes in C stocks and changes in NPP. The C stock-based additional Pmore » demand was estimated to range between -31 and 193 Tg P and between -89 and 262 Tg P for Representative Concentration Pathway (RCP) 2.6 and RCP8.5, respectively, with negative values indicating a P surplus. The NPP-based demand, which takes ecosystem P recycling into account, results in a significantly higher P demand of 648–1606 Tg P for RCP2.6 and 924–2110 Tg P for RCP8.5. We found that the P demand is sensitive to the turnover of P in decomposing plant material, explaining the large differences between the NPP-based demand and C stock-based demand. The discrepancy between diagnosed P demand and actual P availability (potential P deficit) depends mainly on the assumptions about availability of the different soil P forms. Altogether, future P limitation strongly depends on both soil P availability and P recycling on ecosystem scale.« less
Session Limits and the Probability of the Next Visit
ERIC Educational Resources Information Center
Schwartz, Allan J.
2016-01-01
Among the approaches that have been used to balance the demand for services with the agency's service resources is to limit the number of visits available to clients. Such limits have been introduced, however, without any empirical basis for estimating the impact of a limit on the overall demand for services or the proportion of clients. The…
20 CFR 220.135 - Exertional and nonexertional limitations.
Code of Federal Regulations, 2011 CFR
2011-04-01
... limitations of function or restrictions which limit the claimant's ability to meet certain demands of jobs... as exertional if they affect the claimant's ability to meet the strength demands of jobs. The... Department of Labor, to determine the exertional requirements of work which exists in the national economy...
20 CFR 220.135 - Exertional and nonexertional limitations.
Code of Federal Regulations, 2013 CFR
2013-04-01
... limitations of function or restrictions which limit the claimant's ability to meet certain demands of jobs... as exertional if they affect the claimant's ability to meet the strength demands of jobs. The... Department of Labor, to determine the exertional requirements of work which exists in the national economy...
20 CFR 220.135 - Exertional and nonexertional limitations.
Code of Federal Regulations, 2012 CFR
2012-04-01
... limitations of function or restrictions which limit the claimant's ability to meet certain demands of jobs... as exertional if they affect the claimant's ability to meet the strength demands of jobs. The... Department of Labor, to determine the exertional requirements of work which exists in the national economy...
20 CFR 220.135 - Exertional and nonexertional limitations.
Code of Federal Regulations, 2014 CFR
2014-04-01
... limitations of function or restrictions which limit the claimant's ability to meet certain demands of jobs... as exertional if they affect the claimant's ability to meet the strength demands of jobs. The... Department of Labor, to determine the exertional requirements of work which exists in the national economy...
75 FR 3955 - Environmental Impact Statement: Davis and Weber Counties, UT
Federal Register 2010, 2011, 2012, 2013, 2014
2010-01-25
... demand in western Davis and Weber Counties. Although the exact limits of the study area have not been... Weber County. The eastern limits of the study area extend to I-15 and the western limit will be just east of the Great Salt Lake. To provide for local and regional travel demands, the regional...
Opportunities for Automated Demand Response in California Wastewater Treatment Facilities
DOE Office of Scientific and Technical Information (OSTI.GOV)
Aghajanzadeh, Arian; Wray, Craig; McKane, Aimee
Previous research over a period of six years has identified wastewater treatment facilities as good candidates for demand response (DR), automated demand response (Auto-DR), and Energy Efficiency (EE) measures. This report summarizes that work, including the characteristics of wastewater treatment facilities, the nature of the wastewater stream, energy used and demand, as well as details of the wastewater treatment process. It also discusses control systems and automated demand response opportunities. Furthermore, this report summarizes the DR potential of three wastewater treatment facilities. In particular, Lawrence Berkeley National Laboratory (LBNL) has collected data at these facilities from control systems, submetered processmore » equipment, utility electricity demand records, and governmental weather stations. The collected data were then used to generate a summary of wastewater power demand, factors affecting that demand, and demand response capabilities. These case studies show that facilities that have implemented energy efficiency measures and that have centralized control systems are well suited to shed or shift electrical loads in response to financial incentives, utility bill savings, and/or opportunities to enhance reliability of service. In summary, municipal wastewater treatment energy demand in California is large, and energy-intensive equipment offers significant potential for automated demand response. In particular, large load reductions were achieved by targeting effluent pumps and centrifuges. One of the limiting factors to implementing demand response is the reaction of effluent turbidity to reduced aeration at an earlier stage of the process. Another limiting factor is that cogeneration capabilities of municipal facilities, including existing power purchase agreements and utility receptiveness to purchasing electricity from cogeneration facilities, limit a facility’s potential to participate in other DR activities.« less
15 CFR 15.14 - Demand for testimony or production of documents: Department procedures.
Code of Federal Regulations, 2011 CFR
2011-01-01
... represented by an attorney, to refine or limit a demand so that compliance is less burdensome or obtain... 15 Commerce and Foreign Trade 1 2011-01-01 2011-01-01 false Demand for testimony or production of....14 Demand for testimony or production of documents: Department procedures. (a) Whenever a demand for...
Shared filtering processes link attentional and visual short-term memory capacity limits.
Bettencourt, Katherine C; Michalka, Samantha W; Somers, David C
2011-09-30
Both visual attention and visual short-term memory (VSTM) have been shown to have capacity limits of 4 ± 1 objects, driving the hypothesis that they share a visual processing buffer. However, these capacity limitations also show strong individual differences, making the degree to which these capacities are related unclear. Moreover, other research has suggested a distinction between attention and VSTM buffers. To explore the degree to which capacity limitations reflect the use of a shared visual processing buffer, we compared individual subject's capacities on attentional and VSTM tasks completed in the same testing session. We used a multiple object tracking (MOT) and a VSTM change detection task, with varying levels of distractors, to measure capacity. Significant correlations in capacity were not observed between the MOT and VSTM tasks when distractor filtering demands differed between the tasks. Instead, significant correlations were seen when the tasks shared spatial filtering demands. Moreover, these filtering demands impacted capacity similarly in both attention and VSTM tasks. These observations fail to support the view that visual attention and VSTM capacity limits result from a shared buffer but instead highlight the role of the resource demands of underlying processes in limiting capacity.
DOT National Transportation Integrated Search
2016-08-01
The objective of this study is to develop a model for estimating demand for rural demand-response transit services for the general public. Lack of data for demand-response service characteristics and geographic coverage has limited the development of...
48 CFR 1352.271-79 - Liability and insurance.
Code of Federal Regulations, 2014 CFR
2014-10-01
... AND FORMS SOLICITATION PROVISIONS AND CONTRACT CLAUSES Text of Provisions and Clauses 1352.271-79... against all suits, actions, claims, costs or demands (including without limitation, suits, actions, claims.... Such indemnity shall include, without limitation, suits, actions, claims, costs or demands of any kind...
48 CFR 1352.271-79 - Liability and insurance.
Code of Federal Regulations, 2011 CFR
2011-10-01
... AND FORMS SOLICITATION PROVISIONS AND CONTRACT CLAUSES Text of Provisions and Clauses 1352.271-79... against all suits, actions, claims, costs or demands (including without limitation, suits, actions, claims.... Such indemnity shall include, without limitation, suits, actions, claims, costs or demands of any kind...
48 CFR 1352.271-79 - Liability and insurance.
Code of Federal Regulations, 2012 CFR
2012-10-01
... AND FORMS SOLICITATION PROVISIONS AND CONTRACT CLAUSES Text of Provisions and Clauses 1352.271-79... against all suits, actions, claims, costs or demands (including without limitation, suits, actions, claims.... Such indemnity shall include, without limitation, suits, actions, claims, costs or demands of any kind...
48 CFR 1352.271-79 - Liability and insurance.
Code of Federal Regulations, 2013 CFR
2013-10-01
... AND FORMS SOLICITATION PROVISIONS AND CONTRACT CLAUSES Text of Provisions and Clauses 1352.271-79... against all suits, actions, claims, costs or demands (including without limitation, suits, actions, claims.... Such indemnity shall include, without limitation, suits, actions, claims, costs or demands of any kind...
22 CFR 512.9 - Demand for payment.
Code of Federal Regulations, 2010 CFR
2010-04-01
... administrative offset, demand for payment will be made as follows: (a) Written demands will be made promptly upon... three progressively stronger written demands at not more than 30-day intervals will normally be made... Goverment's interests (e.g., to prevent the statute of limitations, 28 U.S.C. 2415, from expiring) written...
DOT National Transportation Integrated Search
2001-08-01
Travel demand management (TDM) is a set of procedures that have been shown to alleviate unlimited use of automobiles. Demand is managed by limiting highway capacity to meet demand to travel by car and providing incentives or disincentives to increase...
NASA Astrophysics Data System (ADS)
Zheng, Han; Yu, Guirui; Wang, Qiufeng; Zhu, Xianjin; Yan, Junhua; Wang, Huimin; Shi, Peili; Zhao, Fenghua; Li, Yingnian; Zhao, Liang; Zhang, Junhui; Wang, Yanfen
2017-08-01
Estimates of atmospheric evaporative demand have been widely required for a variety of hydrological analyses, with potential evapotranspiration (PET) being an important measure representing evaporative demand of actual vegetated surfaces under given metrological conditions. In this study, we assessed the ability of various PET models in capturing long-term (typically 2003-2011) dynamics of evaporative demand at eight ecosystems across various biomes and climatic regimes in China. Prior to assessing PET dynamics, we first examined the reasonability of fourteen PET models in representing the magnitudes of evaporative demand using eddy-covariance actual evapotranspiration (AET) as an indicator. Results showed that the robustness of the fourteen PET models differed somewhat across the sites, and only three PET models could produce reasonable magnitudes of evaporative demand (i.e., PET ≥ AET on average) for all eight sites, including the: (i) Penman; (ii) Priestly-Taylor and (iii) Linacre models. Then, we assessed the ability of these three PET models in capturing dynamics of evaporative demand by comparing the annual and seasonal trends in PET against the equivalent trends in AET and precipitation (P) for particular sites. Results indicated that nearly all the three PET models could faithfully reproduce the dynamics in evaporative demand for the energy-limited conditions at both annual and seasonal scales, while only the Penman and Linacre models could represent dynamics in evaporative demand for the water-limited conditions. However, the Linacre model was unable to reproduce the seasonal switches between water- and energy-limited states for some sites. Our findings demonstrated that the choice of PET models would be essential for the evaporative demand analyses and other related hydrological analyses at different temporal and spatial scales.
Code of Federal Regulations, 2010 CFR
2010-07-01
... shall send appropriate written demands to the debtor in terms which inform the debtor of the..., a total of three progressively stronger written demands at not more than 30-day intervals will... of limitations, 28 U.S.C. 2415, from expiring), written demand may be preceded by other appropriate...
15 CFR 25.6 - Prerequisites for issuing a complaint.
Code of Federal Regulations, 2010 CFR
2010-01-01
... this section), the amount of money, or the value of property or services, demanded or requested in... simultaneously, regardless of the amount of money, or the value of property or services, demanded or requested. ..., demand, or submission. (c) Nothing in this section shall be construed to limit the reviewing official's...
The causes of international labor migrations--a demand-determined approach.
Straubhaar, T
1986-01-01
The author first studies the reasons why people migrate using a neoclassical approach concerning income differentials. He tests this approach empirically and demonstrates its limits. A demand-determination approach based on human capital theory is then outlined to overcome these limits and to take into account restrictive immigration controls. Migration from Italy, Spain, Greece, Portugal, and Turkey to the European Community destination countries is examined. It is concluded that "the demand for immigrants in the destination country is the decisive condition for the phenomenon of international labor migration, and the supply of migration-willing workers is only a necessary condition." excerpt
A Framework to Determine New System Requirements Under Design Parameter and Demand Uncertainties
2015-05-13
Demand fluctuation on a day to day basis – Routes flown vary based on demand – Limited aircraft types: C-5, C-17, C-130, Boeing 747 -F, KC-135, etc...dataset – Demand for subset served by C-5, C-17 and 747 -F (~75% of total demand) – Fixed density and dimension of pallet (463 L) • Our aircraft...fleet consists of only the C-5, C-17 and 747 -F. Source: www.amc.af.mil 30
The Supply and Demand of Teachers and Teaching.
ERIC Educational Resources Information Center
Zerfoss, Evelyn; Shapiro, Leo J.
There is a general oversupply of teachers. Attempts to regulate teacher supply and demand are flawed by assumptions that teachers are a limited consumer item and that the school system will persist in its present form. The financial crises of schools, the demand of accountability, and the challenge to the principle of compulsory education indicate…
7 CFR 1.306 - Prerequisites for issuing a complaint.
Code of Federal Regulations, 2010 CFR
2010-01-01
..., that the amount of money or the value of property or services demanded or requested in violation of § 1... of a single request, demand, or submission, regardless of the amount of money or the value of property or services demanded or requested. (d) Nothing in this section shall be construed to limit the...
NASA Astrophysics Data System (ADS)
Blokker, Mirjam; Agudelo-Vera, Claudia; Moerman, Andreas; van Thienen, Peter; Pieterse-Quirijns, Ilse
2017-04-01
Many researchers have developed drinking water demand models with various temporal and spatial scales. A limited number of models is available at a temporal scale of 1 s and a spatial scale of a single home. The reasons for building these models were described in the papers in which the models were introduced, along with a discussion on their potential applications. However, the predicted applications are seldom re-examined. SIMDEUM, a stochastic end-use model for drinking water demand, has often been applied in research and practice since it was developed. We are therefore re-examining its applications in this paper. SIMDEUM's original purpose was to calculate maximum demands in order to design self-cleaning networks. Yet, the model has been useful in many more applications. This paper gives an overview of the many fields of application for SIMDEUM and shows where this type of demand model is indispensable and where it has limited practical value. This overview also leads to an understanding of the requirements for demand models in various applications.
Common neural substrates for visual working memory and attention.
Mayer, Jutta S; Bittner, Robert A; Nikolić, Danko; Bledowski, Christoph; Goebel, Rainer; Linden, David E J
2007-06-01
Humans are severely limited in their ability to memorize visual information over short periods of time. Selective attention has been implicated as a limiting factor. Here we used functional magnetic resonance imaging to test the hypothesis that this limitation is due to common neural resources shared by visual working memory (WM) and selective attention. We combined visual search and delayed discrimination of complex objects and independently modulated the demands on selective attention and WM encoding. Participants were presented with a search array and performed easy or difficult visual search in order to encode one or three complex objects into visual WM. Overlapping activation for attention-demanding visual search and WM encoding was observed in distributed posterior and frontal regions. In the right prefrontal cortex and bilateral insula blood oxygen-level-dependent activation additively increased with increased WM load and attentional demand. Conversely, several visual, parietal and premotor areas showed overlapping activation for the two task components and were severely reduced in their WM load response under the condition with high attentional demand. Regions in the left prefrontal cortex were selectively responsive to WM load. Areas selectively responsive to high attentional demand were found within the right prefrontal and bilateral occipital cortex. These results indicate that encoding into visual WM and visual selective attention require to a high degree access to common neural resources. We propose that competition for resources shared by visual attention and WM encoding can limit processing capabilities in distributed posterior brain regions.
Modelling inter-supply chain competition with resource limitation and demand disruption
NASA Astrophysics Data System (ADS)
Chen, Zhaobo; Teng, Chunxian; Zhang, Ding; Sun, Jiayi
2016-05-01
This paper proposes a comprehensive model for studying supply chain versus supply chain competition with resource limitation and demand disruption. We assume that there are supply chains with heterogeneous supply network structures that compete at multiple demand markets. Each supply chain is comprised of internal and external firms. The internal firms are coordinated in production and distribution and share some common but limited resources within the supply chain, whereas the external firms are independent and do not share the internal resources. The supply chain managers strive to develop optimal strategies in terms of production level and resource allocation in maximising their profit while facing competition at the end market. The Cournot-Nash equilibrium of this inter-supply chain competition is formulated as a variational inequality problem. We further study the case when there is demand disruption in the plan-execution phase. In such a case, the managers need to revise their planned strategy in order to maximise their profit with the new demand under disruption and minimise the cost of change. We present a bi-criteria decision-making model for supply chain managers and develop the optimal conditions in equilibrium, which again can be formulated by another variational inequality problem. Numerical examples are presented for illustrative purpose.
Dreison, Kimberly C; White, Dominique A; Bauer, Sarah M; Salyers, Michelle P; McGuire, Alan B
2018-01-01
Limited progress has been made in reducing burnout in mental health professionals. Accordingly, we identified factors that might protect against burnout and could be productive focal areas for future interventions. Guided by self-determination theory, we examined whether supervisor autonomy support, self-efficacy, and staff cohesion predict provider burnout. 358 staff from 13 agencies completed surveys. Higher levels of supervisor autonomy support, self-efficacy, and staff cohesion were predictive of lower burnout, even after accounting for job demands. Although administrators may be limited in their ability to reduce job demands, our findings suggest that increasing core job resources may be a viable alternative.
How Sustainable is Groundwater Abstraction? A Global Assessment.
NASA Astrophysics Data System (ADS)
de Graaf, I.; Van Beek, R.; Gleeson, T. P.; Sutanudjaja, E.; Wada, Y.; Bierkens, M. F.
2016-12-01
Groundwater is the world's largest accessible freshwater resource and is of critical importance for irrigation, and thus for global food security. For regions with high demands, groundwater abstractions often exceed recharge and persistent groundwater depletion occurs. The direct effects of depletion are falling groundwater levels, increased pumping costs, land subsidence, and reduced baseflows to rivers. Water demands are expected to increase further due to growing population, economic development, and climate change, posing the urgent question how sustainable current water abstractions are worldwide and where and when these abstractions approach conceivable economic and environmental limits. In this study we estimated trends over 1960-2100 in groundwater levels, resulting from changes in demand and climate. We explored the limits of groundwater abstraction by predicting where and when groundwater levels drop that deep that groundwater gets unattainable for abstraction (economic limit) or, that groundwater baseflows to rivers drop below environmental requirements (environmental limit). We used a global hydrological model coupled to a groundwater model, meaning lateral groundwater flows, river infiltration and drainage, and infiltration and capillary-rise are simulated dynamically. Historical data and projections are used to prescribe water demands and climate forcing to the model. For the near future we used RCP8.5 and applied globally driest, average, and wettest GCM to test climate sensitivity. Results show that in general environmental limits are reached before economic limits, for example starting as early as the 1970s compared to the 1980s for economic limits in the upper Ganges basin. Economic limits are mostly related to regions with depletion, while environmental limits are reached also in regions were groundwater and surface water withdrawals are significant but depletion is not taking place (yet), for example in Spain and Portugal. In the near future, more regions will reach their limits, current depletion regions will expand and new regions experiencing depletion will develop. Regionally the increasing level of groundwater stress, economically and environmentally, will be an important factor in future economic development and could lead to socio-economic tension.
How Sustainable is Groundwater Abstraction? A Global Assessment.
NASA Astrophysics Data System (ADS)
de Graaf, I.; Van Beek, R.; Gleeson, T. P.; Sutanudjaja, E.; Wada, Y.; Bierkens, M. F.
2017-12-01
Groundwater is the world's largest accessible freshwater resource and is of critical importance for irrigation, and thus for global food security. For regions with high demands, groundwater abstractions often exceed recharge and persistent groundwater depletion occurs. The direct effects of depletion are falling groundwater levels, increased pumping costs, land subsidence, and reduced baseflows to rivers. Water demands are expected to increase further due to growing population, economic development, and climate change, posing the urgent question how sustainable current water abstractions are worldwide and where and when these abstractions approach conceivable economic and environmental limits. In this study we estimated trends over 1960-2100 in groundwater levels, resulting from changes in demand and climate. We explored the limits of groundwater abstraction by predicting where and when groundwater levels drop that deep that groundwater gets unattainable for abstraction (economic limit) or, that groundwater baseflows to rivers drop below environmental requirements (environmental limit). We used a global hydrological model coupled to a groundwater model, meaning lateral groundwater flows, river infiltration and drainage, and infiltration and capillary-rise are simulated dynamically. Historical data and projections are used to prescribe water demands and climate forcing to the model. For the near future we used RCP8.5 and applied globally driest, average, and wettest GCM to test climate sensitivity. Results show that in general environmental limits are reached before economic limits, for example starting as early as the 1970s compared to the 1980s for economic limits in the upper Ganges basin. Economic limits are mostly related to regions with depletion, while environmental limits are reached also in regions were groundwater and surface water withdrawals are significant but depletion is not taking place (yet), for example in Spain and Portugal. In the near future, more regions will reach their limits, current depletion regions will expand and new regions experiencing depletion will develop. Regionally the increasing level of groundwater stress, economically and environmentally, will be an important factor in future economic development and could lead to socio-economic tension.
Novick, Kimberly A; Miniat, Chelcy F; Vose, James M
2016-03-01
We merge concepts from stomatal optimization theory and cohesion-tension theory to examine the dynamics of three mechanisms that are potentially limiting to leaf-level gas exchange in trees during drought: (1) a 'demand limitation' driven by an assumption of optimal stomatal functioning; (2) 'hydraulic limitation' of water movement from the roots to the leaves; and (3) 'non-stomatal' limitations imposed by declining leaf water status within the leaf. Model results suggest that species-specific 'economics' of stomatal behaviour may play an important role in differentiating species along the continuum of isohydric to anisohydric behaviour; specifically, we show that non-stomatal and demand limitations may reduce stomatal conductance and increase leaf water potential, promoting wide safety margins characteristic of isohydric species. We used model results to develop a diagnostic framework to identify the most likely limiting mechanism to stomatal functioning during drought and showed that many of those features were commonly observed in field observations of tree water use dynamics. Direct comparisons of modelled and measured stomatal conductance further indicated that non-stomatal and demand limitations reproduced observed patterns of tree water use well for an isohydric species but that a hydraulic limitation likely applies in the case of an anisohydric species. Published 2015. This article is a US Government work and is in the public domain in the USA.
Objective Work-Nonwork Conflict: From Incompatible Demands to Decreased Work Role Performance
ERIC Educational Resources Information Center
Haun, Sascha; Steinmetz, Holger; Dormann, Christian
2011-01-01
Research on work-nonwork conflict (WNC) is based on the assumption that incompatible demands from the work and the nonwork domain hamper role performance. This assumption implies that role demands from both domains interact in predicting role performance, but research has been largely limited to main effects. In this multi-source study, we analyze…
Historical aspects of somatic embryogenesis in woody plants
Subhash C. Minocha; Rakesh Minocha
1995-01-01
During the next few decades, the world demand for wood products is expected to rise sharply. To meet this growing demand, there will be an increasing need for mass production of improved-quality planting stock of many tree species. The conventional methods of tree improvement and selection offer only limited possibility of meeting the growing demands. Therefore, new...
Effective Management of High-Use/High-Demand Space Using Restaurant-Style Pagers
ERIC Educational Resources Information Center
Gonzalez, Adriana
2012-01-01
The library landscape is changing at a fast pace, with an increase in the demand for study space including quiet, individualized study space; open group study space; and as enclosed group study space. In large academic libraries, managing limited high-demand resources is crucial and is partially being driven by the greater emphasis on group…
Relationship of employee-reported work limitations to work productivity.
Lerner, Debra; Amick, Benjamin C; Lee, Jennifer C; Rooney, Ted; Rogers, William H; Chang, Hong; Berndt, Ernst R
2003-05-01
Work limitation rates are crucial indicators of the health status of working people. If related to work productivity, work limitation rates may also supply important information about the economic burden of illness. Our objective was to assess the productivity impact of on-the-job work limitations due to employees' physical or mental health problems. Subjects were asked to complete a self-administered survey on the job during 3 consecutive months. Using robust regression analysis, we tested the relationship of objectively-measured work productivity to employee-reported work limitations. We attempted to survey employees of a large firm within 3 different jobs. The survey response rate was 2245 (85.9%). Full survey and productivity data were available for 1827 respondents. Each survey included a validated self-report instrument, the Work Limitations Questionnaire (WLQ). The firm provided objective, employee-level work productivity data. In adjusted regression analyses (n = 1827), employee work productivity (measured as the log of units produced/hour) was significantly associated with 3 dimensions of work limitations: limitations handling the job's time and scheduling demands (P = 0.003), physical job demands (P = 0.001), and output demands (P = 0.006). For every 10% increase in on-the-job work limitations reported on each of the 3 WLQ scales, work productivity declined approximately 4 to 5%. Employee work limitations have a negative impact on work productivity. Employee assessments of their work limitations supply important proxies for the economic burden of health problems.
Revegetation in China’s Loess Plateau is approaching sustainable water resource limits
NASA Astrophysics Data System (ADS)
Feng, Xiaoming; Fu, Bojie; Piao, Shilong; Wang, Shuai; Ciais, Philippe; Zeng, Zhenzhong; Lü, Yihe; Zeng, Yuan; Li, Yue; Jiang, Xiaohui; Wu, Bingfang
2016-11-01
Revegetation of degraded ecosystems provides opportunities for carbon sequestration and bioenergy production. However, vegetation expansion in water-limited areas creates potentially conflicting demands for water between the ecosystem and humans. Current understanding of these competing demands is still limited. Here, we study the semi-arid Loess Plateau in China, where the `Grain to Green’ large-scale revegetation programme has been in operation since 1999. As expected, we found that the new planting has caused both net primary productivity (NPP) and evapotranspiration (ET) to increase. Also the increase of ET has induced a significant (p < 0.001) decrease in the ratio of river runoff to annual precipitation across hydrological catchments. From currently revegetated areas and human water demand, we estimate a threshold of NPP of 400 +/- 5 g C m-2 yr-1 above which the population will suffer water shortages. NPP in this region is found to be already close to this limit. The threshold of NPP could change by -36% in the worst case of climate drying and high human withdrawals, to +43% in the best case. Our results develop a new conceptual framework to determine the critical carbon sequestration that is sustainable in terms of both ecological and socio-economic resource demands in a coupled anthropogenic-biological system.
Common capacity-limited neural mechanisms of selective attention and spatial working memory encoding
Fusser, Fabian; Linden, David E J; Rahm, Benjamin; Hampel, Harald; Haenschel, Corinna; Mayer, Jutta S
2011-01-01
One characteristic feature of visual working memory (WM) is its limited capacity, and selective attention has been implicated as limiting factor. A possible reason why attention constrains the number of items that can be encoded into WM is that the two processes share limited neural resources. Functional magnetic resonance imaging (fMRI) studies have indeed demonstrated commonalities between the neural substrates of WM and attention. Here we investigated whether such overlapping activations reflect interacting neural mechanisms that could result in capacity limitations. To independently manipulate the demands on attention and WM encoding within one single task, we combined visual search and delayed discrimination of spatial locations. Participants were presented with a search array and performed easy or difficult visual search in order to encode one, three or five positions of target items into WM. Our fMRI data revealed colocalised activation for attention-demanding visual search and WM encoding in distributed posterior and frontal regions. However, further analysis yielded two patterns of results. Activity in prefrontal regions increased additively with increased demands on WM and attention, indicating regional overlap without functional interaction. Conversely, the WM load-dependent activation in visual, parietal and premotor regions was severely reduced during high attentional demand. We interpret this interaction as indicating the sites of shared capacity-limited neural resources. Our findings point to differential contributions of prefrontal and posterior regions to the common neural mechanisms that support spatial WM encoding and attention, providing new imaging evidence for attention-based models of WM encoding. PMID:21781193
Evaluating the potential of improving residential water balance at building scale.
Agudelo-Vera, Claudia M; Keesman, Karel J; Mels, Adriaan R; Rijnaarts, Huub H M
2013-12-15
Earlier results indicated that, for an average household, self-sufficiency in water supply can be achieved by following the Urban harvest Approach (UHA), in a combination of demand minimization, cascading and multi-sourcing. To achieve these results, it was assumed that all available local resources can be harvested. In reality, however, temporal, spatial and location-bound factors pose limitations to this harvest and, thus, to self-sufficiency. This article investigates potential spatial and temporal limitations to harvest local water resources at building level for the Netherlands, with a focus on indoor demand. Two building types were studied, a free standing house (one four-people household) and a mid-rise apartment flat (28 two-person households). To be able to model yearly water balances, daily patterns considering household occupancy and presence of water using appliances were defined per building type. Three strategies were defined. The strategies include demand minimization, light grey water (LGW) recycling, and rainwater harvesting (multi-sourcing). Recycling and multi-sourcing cater for toilet flushing and laundry machine. Results showed that water saving devices may reduce 30% of the conventional demand. Recycling of LGW can supply 100% of second quality water (DQ2) which represents 36% of the conventional demand or up to 20% of the minimized demand. Rainwater harvesting may supply approximately 80% of the minimized demand in case of the apartment flat and 60% in case of the free standing house. To harvest these potentials, different system specifications, related to the household type, are required. Two constraints to recycle and multi-source were identified, namely i) limitations in the grey water production and available rainfall; and ii) the potential to harvest water as determined by the temporal pattern in water availability, water use, and storage and treatment capacities. Copyright © 2013 Elsevier Ltd. All rights reserved.
Nutrient limitation in tropical savannas across multiple scales and mechanisms.
Pellegrini, Adam F A
2016-02-01
Nutrients have been hypothesized to influence the distribution of the savanna biome through two possible mechanisms. Low nutrient availability may restrict growth rates of trees, thereby allowing for intermittent fires to maintain low tree cover; alternatively, nutrient deficiency may even place an absolute constraint on the ability of forests to form, independent of fire. However, we have little understanding of the scales at which nutrient limitation operates, what nutrients are limiting, and the mechanisms that influence how nutrient limitation regulates savanna-forest transitions. Here, I review literature, synthesize existing data, and present a simple calculation of nutrient demand to evaluate how nutrient limitation may regulate the distribution of the savanna biome. The literature primarily supports the hypothesis that nutrients may interact dynamically with fire to restrict the transition of savanna into forest. A compilation of indirect metrics of nutrient limitation suggest that nitrogen and phosphorus are both in short supply and may limit plants. Nutrient demand calculations provided a number of insights. First, trees required high rates of nitrogen and phosphorus supply relative to empirically determined inputs. Second, nutrient demand increased as landscapes approached the transition point between savanna and forest. Third, the potential for fire-driven nutrient losses remained high throughout transitions, which may exaggerate limitation and could be a key feedback stabilizing the savanna biome. Fourth, nutrient limitation varied between functional groups, with fast-growing forest species having substantially greater nutrient demand and a higher susceptibility to fire-driven nutrient losses. Finally, African savanna trees required substantially larger amounts of nutrients supplied at greater rates, although this varied across plant functional groups. In summary, the ability of nutrients to control transitions emerges at individual and landscape scales, and is regulated through different mechanisms based on spatial (differences in underlying geology), temporal (stage in biome transition) and biological (species traits and community composition) variability.
Supply and demand for wood: a worldwide perspective?
Sally Duncan
1998-01-01
In a unique effort to compare and contrast differing views on future supply and demand for wood, a study found that demand for wood will increase, but there is no evidence of a crisis at the world scale. Opportunities to increase wood production, however, are limited and trade-offs among competing uses of forests are inevitable. A complex of factors determine supply...
Demand forecast model based on CRM
NASA Astrophysics Data System (ADS)
Cai, Yuancui; Chen, Lichao
2006-11-01
With interiorizing day by day management thought that regarding customer as the centre, forecasting customer demand becomes more and more important. In the demand forecast of customer relationship management, the traditional forecast methods have very great limitation because much uncertainty of the demand, these all require new modeling to meet the demands of development. In this paper, the notion is that forecasting the demand according to characteristics of the potential customer, then modeling by it. The model first depicts customer adopting uniform multiple indexes. Secondly, the model acquires characteristic customers on the basis of data warehouse and the technology of data mining. The last, there get the most similar characteristic customer by their comparing and forecast the demands of new customer by the most similar characteristic customer.
Mabry, Linda; Parker, Kelsey N; Thompson, Sharon V; Bettencourt, Katrina M; Haque, Afsara; Luther Rhoten, Kristy; Wright, Rob R; Hess, Jennifer A; Olson, Ryan
2018-05-02
The Community of Practice and Safety Support (COMPASS) program is a peer-led group intervention for home care workers. In a randomized controlled trial, COMPASS significantly improved workers' professional support networks and safety and health behaviors. However, quantitative findings failed to capture workers' complex emotional, physical, and social experiences with job demands, resource limitations, and the intervention itself. Therefore, we conducted qualitative follow-up interviews with a sample of participants (n = 28) in the program. Results provided examples of unique physical and psychological demands, revealed stressful resource limitations (e.g., safety equipment access), and elucidated COMPASS's role as a valuable resource.
18 CFR 1301.54 - Requirements for a demand for records or testimony.
Code of Federal Regulations, 2014 CFR
2014-04-01
... Authority, 400 W. Summit Hill Drive, Knoxville, Tennessee 37902. (b) Time limit for serving demands. The... Knoxville, where service 15 days prior will normally be considered sufficient. The General Counsel may, upon...
18 CFR 1301.54 - Requirements for a demand for records or testimony.
Code of Federal Regulations, 2012 CFR
2012-04-01
... Authority, 400 W. Summit Hill Drive, Knoxville, Tennessee 37902. (b) Time limit for serving demands. The... Knoxville, where service 15 days prior will normally be considered sufficient. The General Counsel may, upon...
18 CFR 1301.54 - Requirements for a demand for records or testimony.
Code of Federal Regulations, 2010 CFR
2010-04-01
... Authority, 400 W. Summit Hill Drive, Knoxville, Tennessee 37902. (b) Time limit for serving demands. The... Knoxville, where service 15 days prior will normally be considered sufficient. The General Counsel may, upon...
18 CFR 1301.54 - Requirements for a demand for records or testimony.
Code of Federal Regulations, 2013 CFR
2013-04-01
... Authority, 400 W. Summit Hill Drive, Knoxville, Tennessee 37902. (b) Time limit for serving demands. The... Knoxville, where service 15 days prior will normally be considered sufficient. The General Counsel may, upon...
18 CFR 1301.54 - Requirements for a demand for records or testimony.
Code of Federal Regulations, 2011 CFR
2011-04-01
... Authority, 400 W. Summit Hill Drive, Knoxville, Tennessee 37902. (b) Time limit for serving demands. The... Knoxville, where service 15 days prior will normally be considered sufficient. The General Counsel may, upon...
Feng, S. F.; Schwemmer, M.; Gershman, S. J.; Cohen, J. D.
2014-01-01
Why is it that behaviors that rely on control, so striking in their diversity and flexibility, are also subject to such striking limitations? Typically, people cannot engage in more than a few — and usually only a single — control-demanding task at a time. This limitation was a defining element in the earliest conceptualizations of controlled processing, it remains one of the most widely accepted axioms of cognitive psychology, and is even the basis for some laws (e.g., against the use of mobile devices while driving). Remarkably, however, the source of this limitation is still not understood. Here, we examine one potential source of this limitation, in terms of a tradeoff between the flexibility and efficiency of representation (“multiplexing”) and the simultaneous engagement of different processing pathways (“multitasking”). We show that even a modest amount of multiplexing rapidly introduces cross-talk among processing pathways, thereby constraining the number that can be productively engaged at once. We propose that, given the large number of advantages of efficient coding, the human brain has favored this over the capacity for multitasking of control-demanding processes. PMID:24481850
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.
MacDermid, Joy C; Tang, Kenneth; Sinden, Kathryn E; D'Amico, Robert
2018-05-25
Purpose Performance-based and disease indicators have been widely studied in firefighters; self-reported work role limitations have not. The aim of this study was to describe the distributions and correlations of a generic self-reported Work Limitations Questionnaire (WLQ-26) and firefighting-specific task performance-based tests. Methods Active firefighters from the City of Hamilton Fire Services (n = 293) were recruited. Participants completed the WLQ-26 to quantify on-the-job difficulties over five work domains: work scheduling (4 items), output demands (7 items), physical demands (8 items), mental demands (4 items), and social demands (3 items). A subset of participants (n = 149) were also assessed on hose drag and stair climb with a high-rise pack performance-based tests. Descriptive statistics and correlations were used to compare item/subscale performance; and to describe the inter-relationships between tests. Results The mean WLQ-26 item scores (/5) ranged from 4.1 to 4.4 (median = 5 for all items); most firefighters (54.5-80.5%) selected "difficult none of the time" response option on all items. A substantial ceiling effect was observed across all five WLQ-26 subscales as 44.0-55.6% were in the highest category. Subscale means ranged from 61.8 (social demands) to 78.7 (output demands and physical demands). Internal consistency exceeded 0.90 on all subscales. For the hose drag task, the mean time-to-completion was 48.0 s (SD = 14.5; range 20.4-95.0). For the stair climb task, the mean time-to-completion was 76.7 s (SD = 37.2; range 21.0-218.0). There were no significant correlations between self-report work limitations and performance of firefighting tasks. Conclusions The WLQ-26 measured five domains, but had ceiling effects in firefighters. Performance-based testing showed wider score range, lacked ceiling effects and did not correlate to the WLQ-26. A firefighter-specific, self-report role functioning scale may be needed to identify compromised work role capabilities in firefighters.
Deep Space Spaceflight: The Challenge of Crew Performance in Autonomous Operations
NASA Astrophysics Data System (ADS)
Thaxton, S. S.; Williams, T. J.; Norsk, P.; Zwart, S.; Crucian, B.; Antonsen, E. L.
2018-02-01
Distance from Earth and limited communications in future missions will increase the demands for crew autonomy and dependence on automation, and Deep Space Gateway presents an opportunity to study the impacts of these increased demands on human performance.
Will water scarcity in semiarid regions limit hydraulic fracturing of shale plays?
NASA Astrophysics Data System (ADS)
Scanlon, Bridget R.; Reedy, Robert C.; Nicot, Jean Philippe
2014-12-01
There is increasing concern about water constraints limiting oil and gas production using hydraulic fracturing (HF) in shale plays, particularly in semiarid regions and during droughts. Here we evaluate HF vulnerability by comparing HF water demand with supply in the semiarid Texas Eagle Ford play, the largest shale oil producer globally. Current HF water demand (18 billion gallons, bgal; 68 billion liters, bL in 2013) equates to ˜16% of total water consumption in the play area. Projected HF water demand of ˜330 bgal with ˜62 000 additional wells over the next 20 years equates to ˜10% of historic groundwater depletion from regional irrigation. Estimated potential freshwater supplies include ˜1000 bgal over 20 yr from recharge and ˜10 000 bgal from aquifer storage, with land-owner lease agreements often stipulating purchase of freshwater. However, pumpage has resulted in excessive drawdown locally with estimated declines of ˜100-200 ft in ˜6% of the western play area since HF began in 2009-2013. Non-freshwater sources include initial flowback water, which is ≤5% of HF water demand, limiting reuse/recycling. Operators report shifting to brackish groundwater with estimated groundwater storage of 80 000 bgal. Comparison with other semiarid plays indicates increasing brackish groundwater and produced water use in the Permian Basin and large surface water inputs from the Missouri River in the Bakken play. The variety of water sources in semiarid regions, with projected HF water demand representing ˜3% of fresh and ˜1% of brackish water storage in the Eagle Ford footprint indicates that, with appropriate management, water availability should not physically limit future shale energy production.
Successional dynamics drive tropical forest nutrient limitation
NASA Astrophysics Data System (ADS)
Chou, C.; Hedin, L. O. O.
2017-12-01
It is increasingly recognized that nutrients such as N and P may significantly constrain the land carbon sink. However, we currently lack a complete understanding of these nutrient cycles in forest ecosystems and how to incorporate them into Earth System Models. We have developed a framework of dynamic forest nutrient limitation, focusing on the role of secondary forest succession and canopy gap disturbances as bottlenecks of high plant nutrient demand and limitation. We used succession biomass data to parameterize a simple ecosystem model and examined the dynamics of nutrient limitation throughout tropical secondary forest succession. Due to the patterns of biomass recovery in secondary tropical forests, we found high nutrient demand from rapid biomass accumulation in the earliest years of succession. Depending on previous land use scenarios, soil nutrient availability may also be low in this time period. Coupled together, this is evidence that there may be high biomass nutrient limitation early in succession, which is partially met by abundant symbiotic nitrogen fixation from certain tree species. We predict a switch from nitrogen limitation in early succession to one of three conditions: (i) phosphorus only, (ii) phosphorus plus nitrogen, or (iii) phosphorus, nitrogen, plus light co-limitation. We will discuss the mechanisms that govern the exact trajectory of limitation as forests build biomass. In addition, we used our model to explore scenarios of tropical secondary forest impermanence and the impacts of these dynamics on ecosystem nutrient limitation. We found that secondary forest impermanence exacerbates nutrient limitation and the need for nitrogen fixation early in succession. Together, these results indicate that biomass recovery dynamics early in succession as well as their connection to nutrient demand and limitation are fundamental for understanding and modeling nutrient limitation of the tropical forest carbon sink.
NASA Technical Reports Server (NTRS)
Edwards, Tamsyn El; Martin, Lynne; Bienert, Nancy; Mercer, Joey
2017-01-01
In air traffic control, task demand and workload have important implications for the safety and efficiency of air traffic. Task demand is dynamic, however, research on demand transitions and associated controller perception and performance is limited. In addition, there is a comparatively restricted understanding of the influence of task demand transitions on workload and performance, in association with automation. This study used an air traffic control simulation to investigate the influence of task demand transitions and two conditions of varying automation, on workload and efficiency-related performance. Findings showed that a both the direction of the task demand variation, and the amount of automation, influenced the relationship between workload and performance. Further research is needed to enhance understanding of demand transition and workload history effects on operator experience and performance, in both air traffic control and other safety-critical domains.
DOT National Transportation Integrated Search
2013-10-01
During the last two decades, financial incentives : have become common in efforts to reduce : demand on roadways by motivating commuters to : use alternative modes of transportation. Despite : common use, limited effort has been made to : understand ...
The University -- Old Ghosts and New
ERIC Educational Resources Information Center
Perkins, James A.
1974-01-01
Successful outcomes of the immediate past must not overshadow four challenges in the future for the university -- the demand for equal education; the demand for public accountability; political and military nationalism combined with cultural pluralism; and limited resources for food, fuel, and space. (JH)
A Review of Player Monitoring Approaches in Basketball: Current Trends and Future Directions.
Fox, Jordan L; Scanlan, Aaron T; Stanton, Robert
2017-07-01
Fox, JL, Scanlan, AT, and Stanton, R. A review of player monitoring approaches in basketball: current trends and future directions. J Strength Cond Res 31(7): 2021-2029, 2017-Effective monitoring of players in team sports such as basketball requires an understanding of the external demands and internal responses, as they relate to training phases and competition. Monitoring of external demands and internal responses allows coaching staff to determine the dose-response associated with the imposed training load (TL), and subsequently, if players are adequately prepared for competition. This review discusses measures reported in the literature for monitoring the external demands and internal responses of basketball players during training and competition. The external demands of training and competition were primarily monitored using time-motion analysis, with limited use of microtechnology being reported. Internal responses during training were typically measured using hematological markers, heart rate, various TL models, and perceptual responses such as rating of perceived exertion (RPE). Heart rate was the most commonly reported indicator of internal responses during competition with limited reporting of hematological markers or RPE. These findings show a large discrepancy between the reporting of external and internal measures and training and competition demands. Microsensors, however, may be a practical and convenient method of player monitoring in basketball to overcome the limitations associated with current approaches while allowing for external demands and internal responses to be recorded simultaneously. The triaxial accelerometers of microsensors seem well suited for basketball and warrant validation to definitively determine their place in the monitoring of basketball players. Coaching staff should make use of this technology by tracking individual player responses across the annual plan and using real-time monitoring to minimize factors such as fatigue and injury risk.
Estimating future dental services' demand and supply: a model for Northern Germany.
Jäger, Ralf; van den Berg, Neeltje; Hoffmann, Wolfgang; Jordan, Rainer A; Schwendicke, Falk
2016-04-01
To plan dental services, a spatial estimation of future demands and supply is required. We aimed at estimating demand and supply in 2030 in Northern Germany based on the expected local socio-demography and oral-health-related morbidity, and the predicted number of dentists and their working time. All analyses were performed on zip-code level. Register data were used to determine the number of retiring dentists and to construct regression models for estimating the number of dentists moving into each zip-code area until 2030. Demand was modelled using projected demography and morbidities. Demand-supply ratios were evaluated and spatial analyses applied. Sensitivity analyses were employed to assess robustness of our findings. Compared with 2011, the population decreased (-7% to -11%) and aged (from mean 46 to 51 years) until 2030. Oral-health-related morbidity changed, leading to more periodontal and fewer prosthetic treatments needs, with the overall demand decreasing in all scenarios (-25% to -33%). In contrast, the overall number of dentists did only limitedly change, resulting in moderate decrease in the supplied service quantities (max. -22%). Thus, the demand-supply ratio increased in all but the worst case scenario, but was unequally distributed between spatial units, with several areas being over- and some being under- or none-serviced in 2030. Within the limitations of the underlying data and the required assumptions, this study expects an increasingly polarized ratio of dental services demand and supply in Northern Germany. Our estimation allows to assess the impact of different influence factors on demand or supply and to specifically identify potential challenges for workforce planning and regulation in different spatial units. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Liu, Guo-Tian; Xu, Hong-Guo; Wang, Li-Jun; Li, Shao-Hua
2013-01-01
Background The decline of photosynthesis in plants under low sink demand is well known. Previous studies focused on the relationship between stomatal conductance (g s) and net photosynthetic rate (P n). These studies investigated the effect of changes in Photosystem II (PSII) function on the P n decline under low sink demand. However, little is known about its effects on different limiting steps of electron transport chain in PSII under this condition. Methodology/Principal Finding Two-month-old bean plants were processed by removing pods and flowers (low sink demand). On the 1st day after low sink demand treatment, a decline of P n was accompanied by a decrease in g s and internal-to-ambient CO2 concentration ratio (C i/C a). From the 3rd to 9th day, P n and g s declined continuously while C i/C a ratio remained stable in the treatment. Moreover, these values were lower than that of control. Wk (a parameter reflecting the damage to oxygen evolving complex of the donor side of PSII) values in the treatment were significantly higher than their corresponding control values. However, RCQA (a parameter reflecting the number of active RCs per excited cross-section of PSII) values in the treatment were significantly lower than control from the 5th day. From the 11th to 21st day, P n and g s of the treatment continued to decline and were lower than control. This was accompanied by a decrease of RCQA, and an increase of Wk. Furthermore, the quantum yield parameters φ Po, φ Eo and ψ Eo in the treatment were lower than in control; however, C i/C a values in the treatment gradually increased and were significantly higher than control on the 21st day. Conclusions Stomatal limitation during the early stage, whereas a combination of stomatal and non-stomatal limitation during the middle stage might be responsible for the reduction of P n under low sink demand. Non-stomatal limitation during the late stages after the removal of the sink of roots and pods may also cause P n reduction. The non-stomatal limitation was associated with the inhibition of PSII electron transport chain. Our data suggests that the donor side of PSII was the most sensitive to low sink demand followed by the reaction center of PSII. The acceptor side of PSII may be the least sensitive. PMID:24324626
A Method for Exploiting Redundancy to Accommodate Actuator Limits in Multivariable Systems
NASA Technical Reports Server (NTRS)
Litt, Jonathan; Roulette, Greg
1995-01-01
This paper introduces a new method for accommodating actuator saturation in a multivariable system with actuator redundancy. Actuator saturation can cause significant deterioration in control system performance because unmet demand may result in sluggish transients and oscillations in response to setpoint changes. To help compensate for this problem, a technique has been developed which takes advantage of redundancy in multivariable systems to redistribute the unmet control demand over the remaining useful effectors. This method is not a redesign procedure, rather it modifies commands to the unlimited effectors to compensate for those which are limited, thereby exploiting the built-in redundancy. The original commands are modified by the increments due to unmet demand, but when a saturated effector comes off its limit, the incremental commands disappear and the original unmodified controller remains intact. This scheme provides a smooth transition between saturated and unsaturated modes as it divides up the unmet requirement over any available actuators. This way, if there is sufficiently redundant control authority, performance can be maintained.
Promoting innovation in small markets: Evidence from the market for rare and intractable diseases.
Iizuka, Toshiaki; Uchida, Gyo
2017-07-01
In many medical care markets with limited profit potential, firms often have little incentive to innovate. These include the market for rare diseases, "neglected" tropical diseases, and personalized medicine. Governments and not-for-profit organizations promote innovation in such markets but empirical evidence on the policy effect is limited. We study this issue by analyzing the impact of a demand-side policy in Japan, which reduces the cost sharing of patients with some rare and intractable diseases and attempts to establish and promote the treatment of those diseases. Using clinical trials data taken from public registries, we identify the effect of the policy using a difference-in-difference approach. We find that the demand-side policy increased firms' incentive to innovate: firm-sponsored clinical trials increased 181% (0.16 per disease per year) when covered by the policy. This result indicates that the demand-side policy can be an important part of innovation policies in markets with limited profit potential. Copyright © 2017 Elsevier B.V. All rights reserved.
Exploring How Technology Growth Limits Impact Optimal Carbon dioxide Mitigation Pathways
Energy system optimization models prescribe the optimal mix of technologies and fuels for meeting energy demands over a time horizon, subject to energy supplies, demands, and other constraints. When optimizing, these models will, to the extent allowed, favor the least cost combin...
Thermal energy storage for smart grid applications
NASA Astrophysics Data System (ADS)
Al-Hallaj, Said; Khateeb, Siddique; Aljehani, Ahmed; Pintar, Mike
2018-01-01
Energy consumption for commercial building cooling accounts for 15% of all commercial building's electricity usage [1]. Electric utility companies charge their customers time of use consumption charges (/kWh) and additionally demand usage charges (/kW) to limit peak energy consumption and offset their high operating costs. Thus, there is an economic incentive to reduce both the electricity consumption charges and demand charges by developing new energy efficient technologies. Thermal energy storage (TES) systems using a phase change material (PCM) is one such technology that can reduce demand charges and shift the demand from on-peak to off-peak rates. Ice and chilled water have been used in thermal storage systems for many decades, but they have certain limitations, which include a phase change temperature of 0 degrees Celsius and relatively low thermal conductivity in comparison to other materials, which limit their applications as a storage medium. To overcome these limitations, a novel phase change composite (PCC) TES material was developed that has much higher thermal conductivity that significantly improves the charge / discharge rate and a customizable phase change temperature to allow for better integration with HVAC systems. Compared to ice storage, the PCC TES system is capable of very high heat transfer rate and has lower system and operational costs. Economic analysis was performed to compare the PCC TES system with ice system and favorable economics was proven. A 4.5 kWh PCC TES prototype system was also designed for testing and validation purpose.
Quantifying the Limitation to World Cereal Production Due To Soil Phosphorus Status
NASA Astrophysics Data System (ADS)
Kvakić, Marko; Pellerin, Sylvain; Ciais, Philippe; Achat, David L.; Augusto, Laurent; Denoroy, Pascal; Gerber, James S.; Goll, Daniel; Mollier, Alain; Mueller, Nathaniel D.; Wang, Xuhui; Ringeval, Bruno
2018-01-01
Phosphorus (P) is an essential element for plant growth. Low P availability in soils is likely to limit crop yields in many parts of the world, but this effect has never been quantified at the global scale by process-based models. Here we attempt to estimate P limitation in three major cereals worldwide for the year 2000 by combining information on soil P distribution in croplands and a generic crop model, while accounting for the nature of soil-plant P transport. As a global average, the diffusion-limited soil P supply meets the crop's P demand corresponding to the climatic yield potential, due to the legacy soil P in highly fertilized areas. However, when focusing on the spatial distribution of P supply versus demand, we found strong limitation in regions like North and South America, Africa, and Eastern Europe. Averaged over grid cells where P supply is lower than demand, the global yield gap due to soil P is estimated at 22, 55, and 26% in winter wheat, maize, and rice. Assuming that a fraction (20%) of the annual P applied in fertilizers is directly available to the plant, the global P yield gap lowers by only 5-10%, underlying the importance of the existing soil P supply in sustaining crop yields. The study offers a base for exploring P limitation in crops worldwide but with certain limitations remaining. These could be better accounted for by describing the agricultural P cycle with a fully coupled and mechanistic soil-crop model.
Amlung, Michael; Morris, David H; Hatz, Laura E; Teeters, Jenni B; Murphy, James G; McCarthy, Denis M
2016-07-01
Elevated behavioral economic demand for alcohol has been shown to be associated with drinking and driving in college students. The present study sought to clarify the underlying mechanisms of this relationship by examining whether drinking-and-driving-related cognitions (e.g., attitudes, perceptions, and normative beliefs) mediate the association between alcohol demand and drinking and driving. A total of 134 young adult social drinkers completed an alcohol purchase task and measures of perceived dangerousness of drinking and driving, normative beliefs about drinking and driving, and perceived driving limit (i.e., perceived number of drinks one could consume and still drive safely). The frequency of drinking and driving in the past year was assessed via self-report. Individuals who reported drinking and driving exhibited greater alcohol demand (intensity, Omax, and elasticity) compared with those who did not engage in drinking and driving. Increased demand was also correlated with more favorable drinking-and-driving cognitions. Indirect effects tests revealed that perceived driving limit partially mediated the relationship between alcohol demand and drinking-and-driving behavior, even after accounting for drinking level, sex, and delay discounting. These findings provide further support for the utility of behavioral economic theory in understanding drinking-and-driving behavior. In particular, they provide evidence for one mechanism-drinking-and-driving-related cognitions-by which alcohol demand influences drinking and driving. Additional research using longitudinal and experimental designs is required to confirm this model and to identify other potential mediators.
Optimal crop selection and water allocation under limited water supply in irrigation
NASA Astrophysics Data System (ADS)
Stange, Peter; Grießbach, Ulrike; Schütze, Niels
2015-04-01
Due to climate change, extreme weather conditions such as droughts may have an increasing impact on irrigated agriculture. To cope with limited water resources in irrigation systems, a new decision support framework is developed which focuses on an integrated management of both irrigation water supply and demand at the same time. For modeling the regional water demand, local (and site-specific) water demand functions are used which are derived from optimized agronomic response on farms scale. To account for climate variability the agronomic response is represented by stochastic crop water production functions (SCWPF). These functions take into account different soil types, crops and stochastically generated climate scenarios. The SCWPF's are used to compute the water demand considering different conditions, e.g., variable and fixed costs. This generic approach enables the consideration of 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.
Load limit of a UASB fed septic tank-treated domestic wastewater.
Lohani, Sunil Prasad; Bakke, Rune; Khanal, Sanjay N
2015-01-01
Performance of a 250 L pilot-scale up-flow anaerobic sludge blanket (UASB) reactor, operated at ambient temperatures, fed septic tank effluents intermittently, was monitored for hydraulic retention time (HRT) from 18 h to 4 h. The total suspended solids (TSS), total chemical oxygen demand (CODT), dissolved chemical oxygen demand (CODdis) and suspended chemical oxygen demand (CODss) removal efficiencies ranged from 20 to 63%, 15 to 56%, 8 to 35% and 22 to 72%, respectively, for the HRT range tested. Above 60% TSS and 47% CODT removal were obtained in the combined septic tank and UASB process. The process established stable UASB treatment at HRT≥6 h, indicating a hydraulic load design limit. The tested septic tank-UASB combined system can be a low-cost and effective on-site sanitation solution.
Space Shuttle payload accommodation and trends in customer demands
NASA Technical Reports Server (NTRS)
Hedin, Daniel L.; Wilson, James R.
1992-01-01
This paper will review payload demands for Shuttle resources and services in the pre-Space Station Freedom time frame. Requests for flight in both the Orbiter cargo bay and middeck will be considered. Factors limiting more efficient use of the Shuttle will also be discussed.
DOT National Transportation Integrated Search
2009-05-01
Due to the ever-increasing demand for complementary ADA paratransit trips, transit agencies have instituted a number of actions related to reducing the costs of this type of service, including steps to limit the demand through stricter and more compl...
29 CFR 102.161 - Notification.
Code of Federal Regulations, 2010 CFR
2010-07-01
... by Administrative Offset § 102.161 Notification. (a) The Agency shall send a written demand to the... prevent the statute of limitations, 28 U.S.C. 2415, from expiring), written demand may be preceded by... official responsible for collection of the debt shall send written notice to the debtor, informing such...
40 CFR 27.6 - Prerequisites for issuing a complaint.
Code of Federal Regulations, 2010 CFR
2010-07-01
... paragraph (b) of this section), the amount of money or the value of property or services demanded or... single request, demand, or submission. (c) Nothing in this section shall be construed to limit the... were not submitted simultaneously, regardless of the amount of money, or the value of property or...
41 CFR 105-70.006 - Prerequisites for issuing a complaint.
Code of Federal Regulations, 2010 CFR
2010-07-01
... this section), the amount of money or the value of property or services demanded or requested in... single request, demand, or submission. (c) Nothing in this section shall be construed to limit the... were not submitted simultaneously, regardless of the amount of money or the value of property or...
22 CFR 521.6 - Prerequisites for issuing a complaint.
Code of Federal Regulations, 2010 CFR
2010-04-01
... paragraph (b) of this section), the amount of money or the value of property or services demanded or... single request, demand, or submission. (c) Nothing in this section shall be construed to limit the... were not submitted simultaneously, regardless of the amount of money, or the value of property or...
22 CFR 224.6 - Prerequisites for issuing a complaint.
Code of Federal Regulations, 2010 CFR
2010-04-01
... paragraph (b) of this section), the amount of money or the value of property or services demanded or... single request, demand, or submission. (c) Nothing in this section shall be construed to limit the... were not submitted simultaneously, regardless of the amount of money, or the value of property or...
Communication Planning for Effective Nutrition Programs.
ERIC Educational Resources Information Center
Colle, Royal D.
Primary health and nutrition have been linked with communication in a variety of well-publicized projects. This partnership between communication and nutrition was made necessary by the confrontation between an expanded demand for services and limited resources for meeting the demand. Senior officials have a substantial role to play in seeing that…
Code of Federal Regulations, 2010 CFR
2010-01-01
..., including shipping, warehousing, packaging, and handling costs) does not exceed $10 for a deposit of less... the balance in a demand deposit account and the duration of the account balance shall not be considered the payment of interest on a demand deposit account and shall not be subject to the limitations in...
Code of Federal Regulations, 2011 CFR
2011-01-01
..., including shipping, warehousing, packaging, and handling costs) does not exceed $10 for a deposit of less... the balance in a demand deposit account and the duration of the account balance shall not be considered the payment of interest on a demand deposit account and shall not be subject to the limitations in...
Clinical-outcome-based demand management in health services.
Brogan, C; Lawrence, D; Mayhew, L
2008-01-01
THE PROBLEM OF MANAGING DEMAND: Most healthcare systems have 'third-party payers' who face the problem of keeping within budgets despite pressures to increase resources due to the ageing population, new technologies and patient demands to lower thresholds for care. This paper uses the UK National Health Service as a case study to suggest techniques for system-based demand management, which aims to control demand and costs whilst maintaining the cost-effectiveness of the system. The technique for managing demand in primary, elective and urgent care consists of managing treatment thresholds for appropriate care, using a whole-systems approach and costing the care elements in the system. It is important to analyse activity in relation to capacity and demand. Examples of using these techniques in practice are given. The practical effects of using such techniques need evaluation. If these techniques are not used, managing demand and limiting healthcare expenditure will be at the expense of clinical outcomes and unmet need, which will perpetuate financial crises.
Solar + Storage Synergies for Managing Commercial-Customer Demand Charges
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gagnon, P.; Govindarajan, A.; Bird, L.
Demand charges, which are based on a customer’s maximum demand in kilowatts (kW), are a common element of electricity rate structures for commercial customers. Customer-sited solar photovoltaic (PV) systems can potentially reduce demand charges, but the level of savings is difficult to predict, given variations in demand charge designs, customer loads, and PV generation profiles. Lawrence Berkeley National Laboratory (Berkeley Lab) and the National Renewable Energy Laboratory (NREL) are collaborating on a series of studies to understand how solar PV can impact demand charges. Prior studies in the series examined demand charge reductions from solar on a stand-alone basis formore » residential and commercial customers. Those earlier analyses found that solar, alone, has limited ability to reduce demand charges depending on the specific design of the demand charge and on the shape of the customer’s load profile. This latest analysis estimates demand charge savings from solar in commercial buildings when co-deployed with behind-the-meter storage, highlighting the complementary roles of the two technologies. The analysis is based on simulated loads, solar generation, and storage dispatch across a wide variety of building types, locations, system configurations, and demand charge designs.« less
Photosynthesis of young apple trees in response to low sink demand under different air temperatures.
Fan, Pei G; Li, Lian S; Duan, Wei; Li, Wei D; Li, Shao H
2010-03-01
Gas exchange, chlorophyll fluorescence, photosynthetic end products and related enzymes in source leaves in response to low sink demand after girdling to remove the root sink were assessed in young apple trees (Malus pumila) grown in two greenhouses with different air temperatures for 5 days. Compared with the non-girdled control in the low-temperature greenhouse (diurnal maximum air temperature <32 degrees C), low sink demand resulted in lower net photosynthetic rate (P(n)), stomatal conductance (g(s)) and transpiration rate (E) but higher leaf temperature on Day 5, while in the high-temperature greenhouse (diurnal maximum air temperature >36 degrees C), P(n), g(s) and E declined from Day 3 onwards. Moreover, gas exchange responded more to low sink demand in the high-temperature greenhouse than in the low-temperature greenhouse. Decreased P(n) at low sink demand was accompanied by lower intercellular CO(2) concentrations in the low-temperature greenhouse. However, decreased maximal photochemical efficiency, potential activity, efficiency of excitation capture, actual efficiency and photochemical quenching, with increased minimal fluorescence and non-photochemical quenching of photosystem II (PSII), were observed in low sink demand leaves only in the high-temperature greenhouse. In addition, low sink demand increased leaf starch and soluble carbohydrate content in both greenhouses but did not result in lower activity of enzymes involved in metabolism. Thus, decreased P(n) under low sink demand was independent of a direct effect of end-product feedback but rather depended on a high temperature threshold. The lower P(n) was likely due to stomatal limitation in the low-temperature greenhouse, but mainly due to non-stomatal limitation in the high-temperature greenhouse.
Nutritional Considerations for Performance in Young Athletes
Smith, JohnEric W.; Holmes, Megan E.; McAllister, Matthew J.
2015-01-01
Nutrition is an integral component to any athletes training and performance program. In adults the balance between energy intake and energy demands is crucial in training, recovery, and performance. In young athletes the demands for training and performance remain but should be a secondary focus behind the demands associated with maintaining the proper growth and maturation. Research interventions imposing significant physiological loads and diet manipulation are limited in youth due to the ethical considerations related to potential negative impacts on the growth and maturation processes associated with younger individuals. This necessary limitation results in practitioners providing nutritional guidance to young athletes to rely on exercise nutrition recommendations intended for adults. While many of the recommendations can appropriately be repurposed for the younger athlete attention needs to be taken towards the differences in metabolic needs and physiological differences. PMID:26464898
Matthews, Lynn T; Beyeza-Kashesya, Jolly; Cooke, Ian; Davies, Natasha; Heffron, Renee; Kaida, Angela; Kinuthia, John; Mmeje, Okeoma; Semprini, Augusto E; Weber, Shannon
2018-06-01
Safer conception interventions reduce HIV incidence while supporting the reproductive goals of people living with or affected by HIV. We developed a consensus statement to address demand, summarize science, identify information gaps, outline research and policy priorities, and advocate for safer conception services. This statement emerged from a process incorporating consultation from meetings, literature, and key stakeholders. Three co-authors developed an outline which was discussed and modified with co-authors, working group members, and additional clinical, policy, and community experts in safer conception, HIV, and fertility. Co-authors and working group members developed and approved the final manuscript. Consensus across themes of demand, safer conception strategies, and implementation were identified. There is demand for safer conception services. Access is limited by stigma towards PLWH having children and limits to provider knowledge. Efficacy, effectiveness, safety, and acceptability data support a range of safer conception strategies including ART, PrEP, limiting condomless sex to peak fertility, home insemination, male circumcision, STI treatment, couples-based HIV testing, semen processing, and fertility care. Lack of guidelines and training limit implementation. Key outstanding questions within each theme are identified. Consumer demand, scientific data, and global goals to reduce HIV incidence support safer conception service implementation. We recommend that providers offer services to HIV-affected men and women, and program administrators integrate safer conception care into HIV and reproductive health programs. Answers to outstanding questions will refine services but should not hinder steps to empower people to adopt safer conception strategies to meet reproductive goals.
An energy balance concept for habitability.
Hoehler, Tori M
2007-12-01
Habitability can be formulated as a balance between the biological demand for energy and the corresponding potential for meeting that demand by transduction of energy from the environment into biological process. The biological demand for energy is manifest in two requirements, analogous to the voltage and power requirements of an electrical device, which must both be met if life is to be supported. These requirements exhibit discrete (non-zero) minima whose magnitude is set by the biochemistry in question, and they are increased in quantifiable fashion by (i) deviations from biochemically optimal physical and chemical conditions and (ii) energy-expending solutions to problems of resource limitation. The possible rate of energy transduction is constrained by (i) the availability of usable free energy sources in the environment, (ii) limitations on transport of those sources into the cell, (iii) upper limits on the rate at which energy can be stored, transported, and subsequently liberated by biochemical mechanisms (e.g., enzyme saturation effects), and (iv) upper limits imposed by an inability to use "power" and "voltage" at levels that cause material breakdown. A system is habitable when the realized rate of energy transduction equals or exceeds the biological demand for energy. For systems in which water availability is considered a key aspect of habitability (e.g., Mars), the energy balance construct imposes additional, quantitative constraints that may help to prioritize targets in search-for-life missions. Because the biological need for energy is universal, the energy balance construct also helps to constrain habitability in systems (e.g., those envisioned to use solvents other than water) for which little constraint currently exists.
Western municipal water conservation policy: The case of disaggregated demand
NASA Astrophysics Data System (ADS)
Burness, Stuart; Chermak, Janie; Krause, Kate
2005-03-01
We investigate aspects of the felicity of both incentive-based and command and control policies in effecting municipal water conservation goals. When demand can be disaggregated according to uses or users, our results suggest that policy efforts be focused on the submarket wherein demand is more elastic. Under plausible consumer parameters, a household production function approach to water utilization prescribes the nature of demand elasticities in alternative uses and squares nicely with empirical results from the literature. An empirical example illustrates. Overall, given data and other informational limitations, extant institutional structures, and in situ technology, our analysis suggests a predisposition for command and control policies over incentive-based tools.
Trends of jet fuel demand and properties
NASA Technical Reports Server (NTRS)
Friedman, R.
1984-01-01
Petroleum industry forecasts predict an increasing demand for jet fuels, a decrease in the gasoline-to-distillate (heavier fuel) demand ratio, and a greater influx of poorer quality petroleum in the next two to three decades. These projections are important for refinery product analyses. The forecasts have not been accurate, however, in predicting the recent, short term fluctuations in jet fuel and competing product demand. Changes in petroleum quality can be assessed, in part, by a review of jet fuel property inspections. Surveys covering the last 10 years show that average jet fuel freezing points, aromatic contents, and smoke points have trends toward their specification limits.
NASA Astrophysics Data System (ADS)
Glushkova, Yu O.; Gordashnukova, O. Yu; Pahomova, A. V.; Shatohina, S. P.; Filippov, D. V.
2018-05-01
The modern markets are characterized by fierce competition, constantly changing demand, increasing demands of consumers, shortening of the life cycle of goods and services in connection with scientific and technological progress. Therefore, for survival, modern logistic systems of industrial enterprises must be constantly improved. Modern economic literature is represented by a large volume of publications on various aspects of the studied issues. They consider the issues of project management in the logistics system that inevitably encounter with triple Limited. It initially describes the balance between project content, cost, and time. Later it was suggested to either replace the content with quality or add a fourth criterion. Therefore it is possible to name such limitation as triple or four-criteria limitation.
The increasing importance of atmospheric demand for ecosystem water and carbon fluxes
Kimberly A. Novick; Darren L. Ficklin; Paul C. Stoy; Christopher A. Williams; Gil Bohrer; Andrew C. Oishi; Shirley A. Papuga; Peter D. Blanken; Asko Noormets; Benjamin N. Sulman; Russell L. Scott; Lixin Wang; Richard P. Phillips
2016-01-01
Soil moisture supply and atmospheric demand for water independently limit-and profoundly affect-vegetation productivity and water use during periods of hydrologic stress1-4. Disentangling the impact of these two drivers on ecosystem carbon and water cycling is difficult because they are often correlated, and experimental tools for manipulating...
World Food Security and Insecurity, 1984-2000.
ERIC Educational Resources Information Center
Farrell, Kenneth R.
Effective economic demand, rather than resource constraints, will continue to be the dominant limiting factor in improving the security of world food supplies between now and the year 2000. The global demand for food will continue to grow but the rate of growth is declining in virtually all regions, easing the pressure on agricultural resources.…
Strategic outsourcing of clinical services: a model for volume-stressed academic medical centers.
Billi, John E; Pai, Chih-Wen; Spahlinger, David A
2004-01-01
Many academic medical centers have significant capacity constraints and limited ability to expand services to meet demand. Health care management should employ strategic thinking to deal with service demands. This article uses three organizational models to develop a theoretical framework to guide the selection of clinical services for outsourcing.
Examining Client Motivation and Counseling Outcome in a University Mental Health Clinic
ERIC Educational Resources Information Center
Ilagan, Guy E.
2009-01-01
University mental health clinics have experienced a marked increase in demand for services without an increase in resources to meet the rising demand. Consequently, university mental health centers need strategies to determine the best allocation of their limited resources. Transtheoretical Model, based on client motivation, may offer valuable…
The Politics of Co-Production: Risks, Limits and Pollution
ERIC Educational Resources Information Center
Flinders, Matthew; Wood, Matthew; Cunningham, Malaika
2016-01-01
Co-production is a risky method of social inquiry. It is time-consuming, ethically complex, emotionally demanding, inherently unstable, vulnerable to external shocks, subject to competing demands and it challenges many disciplinary norms. This is what makes it so fresh and innovative. And yet these research-related risks are rarely discussed and,…
ERIC Educational Resources Information Center
Diestel, Stefan; Schmidt, Klaus-Helmut
2010-01-01
Two specific sources of stress at work have recently received increasing attention in organizational stress research: emotional dissonance (ED) and self-control demands (SCDs). Both theoretical arguments and experimental findings in basic research strongly suggest that ED and different SCDs draw on a common limited regulatory resource.…
Role of the Freight Sector in Future Climate Change Mitigation Scenarios
Muratori, Matteo; Smith, Steven J.; Kyle, Page; ...
2017-02-27
The freight sector's role is examined using the Global Change Assessment Model (GCAM) for a range of climate change mitigation scenarios and future freight demand assumptions. Energy usage and CO 2 emissions from freight have historically grown with a correlation to GDP, and there is limited evidence of near-term global decoupling of freight demand from GDP. Over the 21 st century, greenhouse gas (GHG) emissions from freight are projected to grow faster than passenger transportation or other major end-use sectors, with the magnitude of growth dependent on the assumed extent of long-term decoupling. In climate change mitigation scenarios that applymore » a price to GHG emissions, mitigation of freight emissions (including the effects of demand elasticity, mode and technology shifting, and fuel substitution) is more limited than for other demand sectors. In such scenarios, shifting to less-emitting transportation modes and technologies is projected to play a relatively small role in reducing freight emissions in GCAM. Finally, by contrast, changes in the supply chain of liquid fuels that reduce the fuel carbon intensity, especially deriving from large-scale use of biofuels coupled to carbon capture and storage technologies, are responsible for the majority of freight emissions mitigation, followed by price-induced reduction in freight demand services.« less
Role of the Freight Sector in Future Climate Change Mitigation Scenarios
DOE Office of Scientific and Technical Information (OSTI.GOV)
Muratori, Matteo; Smith, Steven J.; Kyle, Page
The freight sector's role is examined using the Global Change Assessment Model (GCAM) for a range of climate change mitigation scenarios and future freight demand assumptions. Energy usage and CO 2 emissions from freight have historically grown with a correlation to GDP, and there is limited evidence of near-term global decoupling of freight demand from GDP. Over the 21 st century, greenhouse gas (GHG) emissions from freight are projected to grow faster than passenger transportation or other major end-use sectors, with the magnitude of growth dependent on the assumed extent of long-term decoupling. In climate change mitigation scenarios that applymore » a price to GHG emissions, mitigation of freight emissions (including the effects of demand elasticity, mode and technology shifting, and fuel substitution) is more limited than for other demand sectors. In such scenarios, shifting to less-emitting transportation modes and technologies is projected to play a relatively small role in reducing freight emissions in GCAM. Finally, by contrast, changes in the supply chain of liquid fuels that reduce the fuel carbon intensity, especially deriving from large-scale use of biofuels coupled to carbon capture and storage technologies, are responsible for the majority of freight emissions mitigation, followed by price-induced reduction in freight demand services.« less
Role of the Freight Sector in Future Climate Change Mitigation Scenarios.
Muratori, Matteo; Smith, Steven J; Kyle, Page; Link, Robert; Mignone, Bryan K; Kheshgi, Haroon S
2017-03-21
The freight sector's role is examined using the Global Change Assessment Model (GCAM) for a range of climate change mitigation scenarios and future freight demand assumptions. Energy usage and CO 2 emissions from freight have historically grown with a correlation to GDP, and there is limited evidence of near-term global decoupling of freight demand from GDP. Over the 21 st century, greenhouse gas (GHG) emissions from freight are projected to grow faster than passenger transportation or other major end-use sectors, with the magnitude of growth dependent on the assumed extent of long-term decoupling. In climate change mitigation scenarios that apply a price to GHG emissions, mitigation of freight emissions (including the effects of demand elasticity, mode and technology shifting, and fuel substitution) is more limited than for other demand sectors. In such scenarios, shifting to less-emitting transportation modes and technologies is projected to play a relatively small role in reducing freight emissions in GCAM. By contrast, changes in the supply chain of liquid fuels that reduce the fuel carbon intensity, especially deriving from large-scale use of biofuels coupled to carbon capture and storage technologies, are responsible for the majority of freight emissions mitigation, followed by price-induced reduction in freight demand services.
NASA Technical Reports Server (NTRS)
Donoue, George; Hoffman, Karla; Sherry, Lance; Ferguson, John; Kara, Abdul Qadar
2010-01-01
The air transportation system is a significant driver of the U.S. economy, providing safe, affordable, and rapid transportation. During the past three decades airspace and airport capacity has not grown in step with demand for air transportation; the failure to increase capacity at the same rate as the growth in demand results in unreliable service and systemic delay. This report describes the results of an analysis of airline strategic decision-making that affects geographic access, economic access, and airline finances, extending the analysis of these factors using historic data (from Part 1 of the report). The Airline Schedule Optimization Model (ASOM) was used to evaluate how exogenous factors (passenger demand, airline operating costs, and airport capacity limits) affect geographic access (markets-served, scheduled flights, aircraft size), economic access (airfares), airline finances (profit), and air transportation efficiency (aircraft size). This analysis captures the impact of the implementation of airport capacity limits, as well as the effect of increased hedged fuel prices, which serve as a proxy for increased costs per flight that might occur if auctions or congestion pricing are imposed; also incorporated are demand elasticity curves based on historical data that provide information about how passenger demand is affected by airfare changes.
Some Neglected Economic Factors behind Recent Tax and Spending Limitation Movements.
ERIC Educational Resources Information Center
Boskin, Michael J.
1979-01-01
The demand for tax and spending limitations is caused primarily by the generally unrecognized complete lack of growth in real private income since 1973. Journal availability: see EA 511 898. (Author/IRT)
Expanding Regional Airport Usage to Accommodate Increased Air Traffic Demand
NASA Technical Reports Server (NTRS)
Russell, Carl R.
2009-01-01
Small regional airports present an underutilized source of capacity in the national air transportation system. This study sought to determine whether a 50 percent increase in national operations could be achieved by limiting demand growth at large hub airports and instead growing traffic levels at the surrounding regional airports. This demand scenario for future air traffic in the United States was generated and used as input to a 24-hour simulation of the national airspace system. Results of the demand generation process and metrics predicting the simulation results are presented, in addition to the actual simulation results. The demand generation process showed that sufficient runway capacity exists at regional airports to offload a significant portion of traffic from hub airports. Predictive metrics forecast a large reduction of delays at most major airports when demand is shifted. The simulation results then show that offloading hub traffic can significantly reduce nationwide delays.
Cognitive task demands, self-control demands and the mental well-being of office workers.
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.
Limitations of Community College Benchmarking and Benchmarks
ERIC Educational Resources Information Center
Bers, Trudy H.
2006-01-01
This chapter distinguishes between benchmarks and benchmarking, describes a number of data and cultural limitations to benchmarking projects, and suggests that external demands for accountability are the dominant reason for growing interest in benchmarking among community colleges.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bhattarai, Bishnu; Kouzelis, Konstantinos; Mendaza, Iker
The gradual active load penetration in low voltage distribution grids is expected to challenge their network capacity in the near future. Distribution system operators should for this reason resort to either costly grid reinforcements or to demand side management mechanisms. Since demand side management implementation is usually cheaper, it is also the favorable solution. To this end, this article presents a framework for handling grid limit violations, both voltage and current, to ensure a secure and qualitative operation of the distribution grid. This framework consists of two steps, namely a proactive centralized and subsequently a reactive decentralized control scheme. Themore » former is employed to balance the one hour ahead load while the latter aims at regulating the consumption in real-time. In both cases, the importance of fair use of electricity demand flexibility is emphasized. Thus, it is demonstrated that this methodology aids in keeping the grid status within preset limits while utilizing flexibility from all flexibility participants.« less
Recent advancements towards green optical networks
NASA Astrophysics Data System (ADS)
Davidson, Alan; Glesk, Ivan; Buis, Adrianus; Wang, Junjia; Chen, Lawrence
2014-12-01
Recent years have seen a rapid growth in demand for ultra high speed data transmission with end users expecting fast, high bandwidth network access. With this rapid growth in demand, data centres are under pressure to provide ever increasing data rates through their networks and at the same time improve the quality of data handling in terms of reduced latency, increased scalability and improved channel speed for users. However as data rates increase, present technology based on well-established CMOS technology is becoming increasingly difficult to scale and consequently data networks are struggling to satisfy current network demand. In this paper the interrelated issues of electronic scalability, power consumption, limited copper interconnect bandwidth and the limited speed of CMOS electronics will be explored alongside the tremendous bandwidth potential of optical fibre based photonic networks. Some applications of photonics to help alleviate the speed and latency in data networks will be discussed.
Stevenson, Richard J.; Attuquayefio, Tuki
2013-01-01
Human and animal olfactory perception is shaped both by functional demands and by various environmental constraints seemingly peculiar to chemical stimuli. These demands and constraints may have generated a sensory system that is cognitively distinct from the major senses. In this article we identify these various functional demands and constraints, and examine whether they can be used to account for olfaction's unique cognitive features on a case-by-case basis. We then use this as grounds to argue that specific conscious processes do have functional value, a finding that naturally emerges when a comparative approach to consciousness across the senses is adopted. More generally, we conclude that certain peculiar features of olfactory cognition may owe more to limited neocortical processing resources, than they do to the challenges faced by perceiving chemical stimuli. PMID:24198808
Lachance, Christina R; Erby, Lori A H; Ford, Beth M; Allen, Vincent C; Kaphingst, Kimberly A
2010-05-01
As direct-to-consumer genetic testing becomes more available, a diverse group of consumers, including those with limited health literacy, may consider testing. In light of concerns raised about direct-to-consumer genetic testing, this study sought to critically examine whether the informational content, literacy demands, and usability of health-related direct-to-consumer websites met existing recommendations. A content analysis was performed on 29 health-related direct-to-consumer websites. Two coders independently evaluated each website for informational content (e.g., benefits, limitations), literacy demands (e.g., reading level), and usability (e.g., ease of navigation). Most sites presented health conditions and some markers for which they tested, benefits of testing, a description of the testing process, and their privacy policy. Fewer cited scientific literature, explained test limitations, or provided an opportunity to consult a health professional. Key informational content was difficult to locate on most sites. Few sites gave sample disease risk estimates or used common language and explained technical terms consistently. Average reading level was grade 15. The quality of informational content, literacy demands, and usability across health-related direct-to-consumer websites varied widely. Many users would struggle to find and understand the important information. For consumers to better understand the content on these sites and evaluate the meaning of the tests for their health, sites should lower the demands placed on users by distilling and prioritizing the key informational content while simultaneously attending to the reading level and usability elements. In the absence of regulation compelling such changes, government agencies or professional organizations may need to increase consumer and provider awareness of these issues.
Economic concepts to address future water supply-demand imbalances in Iran, Morocco and Saudi Arabia
NASA Astrophysics Data System (ADS)
Hellegers, Petra; Immerzeel, Walter; Droogers, Peter
2013-10-01
In Middle East and North Africa (MENA) countries, renewable groundwater and surface water supply are limited while demand for water is growing rapidly. Climate change is expected to increase water demand even further. The main aim of this paper is to evaluate the water supply-demand imbalances in Iran, Morocco and Saudi Arabia in 2040-2050 under dry, average and wet climate change projections and to show on the basis of the marginal cost and marginal value of water the optimum mix of supply-side and demand-side adjustments to address the imbalance. A hydrological model has been used to estimate the water supply-demand imbalance. Water supply and demand curves have been used to explore for which (marginal value of) water usage the marginal cost of supply-enhancement becomes too expensive. The results indicate that in the future in all cases, except in Iran under the wet climate projection, the quantity of water demanded has to be reduced considerably to address the imbalance, which is indeed what is currently happening already.
The active learning hypothesis of the job-demand-control model: an experimental examination.
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.
Three essays in energy consumption: Time series analyses
NASA Astrophysics Data System (ADS)
Ahn, Hee Bai
1997-10-01
Firstly, this dissertation investigates that which demand specification is an appropriate model for long-run energy demand between the conventional demand specification and the limited demand specification. In order to determine the components of a stable long-run demand for different sectors of the energy industry, I perform cointegration tests by using the Johansen test procedure. First, I test the conventional demand specification including prices and income as components. Second, I test a limited demand specification only income as a component. The reason for performing these tests is that we can determine that which demand specification is a good long-run predictor of energy consumption between the two demand specifications by using the cointegration tests. Secondly, for the purpose of planning and forecasting energy demand in case of cointegrated system, long-run elasticities are of particular interest. To retrieve the optimal level of energy demand in case of price shock, we need long-run elasticities rather than short-run elasticities. The energy demand study provides valuable information to the energy policy makers who are concerned about the long-run impact of taxes and tariffs. A long-run price elasticity is a primary barometer of the substitution effect between energy and non-energy inputs and long-run income elasticity is an important factor since we can measure the energy demand growing slowly or fast than in the past depending on the magnitude of long-run elasticity. The one other problem in estimating the total energy demand is that there exists an aggregation bias stemming from the process of summation in four different energy types for the total aggregation prices and total aggregation energy consumption. In order to measure the aggregation bias between the Btu aggregation method and the Divisia Index method, i.e., which methodology has less aggregation bias in the long-run, I compare the two estimation results with calculated results estimated on a disaggregated basis. Thus, we can confirm whether or not the theoretically superior methodology has less aggregation bias in empirical estimation. Thirdly, I investigate the causal relationships between energy use and GDP. In order to detect causal relationships both in the long-run and in the short-run, the VECM (Vector Error Correction Model) can be used if there exists cointegration relationships among the variables. I detect the causal effects between energy use and GDP by estimating the VECM based on the multivariate production function including the labor and capital variables.
Resource Limitations, the Demand for Education and Economic Growth--A Macroeconomic View.
ERIC Educational Resources Information Center
Stam, Jerome M.
To develop a theoretical framework for explaining the observed change in demand for human skill and knowledge that occurs with economic growth, a macroeconomic analysis was made of economic variables which are influenced by political, social, and cultural factors. In the three-dimensional framework, total output (Y) of all final goods and services…
Estimating the Efficiency of Therapy Groups in a College Counseling Center
ERIC Educational Resources Information Center
Weatherford, Ryan D.
2017-01-01
College counseling centers are facing rapidly increasing demands for services and are tasked to find efficient ways of providing adequate services while managing limited space. The use of therapy groups has been proposed as a method of managing demand. This brief report examines the clinical time savings of a traditional group therapy program in a…
ERIC Educational Resources Information Center
McCormick, Melody
2016-01-01
Student learning is greatest in classrooms where students engage in problem solving tasks that are cognitively demanding. However, there are growing concerns that many Australian students are given limited opportunities to engage in these types of tasks. 108 upper primary school teachers were surveyed to examine task features and cognitive demand…
Single Student Parents Face Financial Difficulties, Debt, without Adequate Aid. Fact Sheet #C394
ERIC Educational Resources Information Center
Miller, Kevin
2012-01-01
Parents with dependent children were nearly one quarter of students enrolled for credit at American postsecondary institutions in 2008. These students face significant challenges to remaining enrolled and graduating, including limited access to affordable child care, difficulty balancing the demands of school with the demands of work and family,…
Federal Register 2010, 2011, 2012, 2013, 2014
2013-09-19
... significant at the typical demand levels, especially when available runways or adverse weather conditions... retime flights to less congested periods. Slots for new flights will be limited to off-peak times to... extent possible. Currently, the peak demand period at SFO is approximately 0900 to 1400 Pacific Time. In...
Belaid, L; Dumont, A; Chaillet, N; Zertal, A; De Brouwere, V; Hounton, S; Ridde, V
2016-10-01
To synthesise evidence on the implementation, costs and cost-effectiveness of demand generation interventions and their effectiveness in improving uptake of modern contraception methods. A Cochrane systematic review was conducted. Searches were performed in electronic databases (MEDLINE, EMBASE) and the grey literature. Randomised controlled trials, cluster randomised trials and quasi-experimental studies, including controlled before-after studies (CBAs) and cost and cost-effectiveness studies that aimed to assess demand interventions (including community- and facility-based interventions, financial mechanisms and mass media campaigns) in low- and middle-income countries were considered. Meta-analyses and narrative synthesis were conducted. In total, 20 papers meeting the inclusion criteria were included in this review. Of those, 13 were used for meta-analysis. Few data were available on implementation and on the influence of context on demand interventions. Involving family members during counselling, providing education activities and increasing exposure to those activities could enhance the success of demand interventions. Demand generation interventions were positively associated with increases in current use (pooled OR 1.57; 95% CI: 1.46-1.69, P < 0.01). Financial mechanism interventions (vouchers) appeared effective to increase use of modern contraceptive methods (pooled OR 2.16; 95% CI: 1.91-2.45, P < 0.01; I 2 = 0%). Demand interventions improved knowledge (pooled OR 1.02; 95% CI 0.63-1.64, P = 0.93) and attitudes towards family planning and improved discussion with partners/husbands around modern contraceptive methods. However, given the limited number of studies included in each category of demand generation interventions, the dates of publication of the studies and their low quality, caution is advised in considering the results. Very limited evidence was available on costs; studies including data on costs were old and inconsistent. Demand generation interventions contribute to increases in modern contraceptive methods use. However, more studies with robust designs are needed to identify the most effective demand generation intervention to increase uptake of modern contraceptive methods. More evidence is also needed about implementation, costs and cost-effectiveness to inform decisions on sustainability and scaling-up. © 2016 The Authors. Tropical Medicine & International Health Published by John Wiley & Sons Ltd.
Demand Side Management: An approach to peak load smoothing
NASA Astrophysics Data System (ADS)
Gupta, Prachi
A preliminary national-level analysis was conducted to determine whether Demand Side Management (DSM) programs introduced by electric utilities since 1992 have made any progress towards their stated goal of reducing peak load demand. Estimates implied that DSM has a very small effect on peak load reduction and there is substantial regional and end-user variability. A limited scholarly literature on DSM also provides evidence in support of a positive effect of demand response programs. Yet, none of these studies examine the question of how DSM affects peak load at the micro-level by influencing end-users' response to prices. After nearly three decades of experience with DSM, controversy remains over how effective these programs have been. This dissertation considers regional analyses that explore both demand-side solutions and supply-side interventions. On the demand side, models are estimated to provide in-depth evidence of end-user consumption patterns for each North American Electric Reliability Corporation (NERC) region, helping to identify sectors in regions that have made a substantial contribution to peak load reduction. The empirical evidence supports the initial hypothesis that there is substantial regional and end-user variability of reductions in peak demand. These results are quite robust in rapidly-urbanizing regions, where air conditioning and lighting load is substantially higher, and regions where the summer peak is more pronounced than the winter peak. It is also evident from the regional experiences that active government involvement, as shaped by state regulations in the last few years, has been successful in promoting DSM programs, and perhaps for the same reason we witness an uptick in peak load reductions in the years 2008 and 2009. On the supply side, we estimate the effectiveness of DSM programs by analyzing the growth of capacity margin with the introduction of DSM programs. The results indicate that DSM has been successful in offsetting the need for additional production capacity by the means of demand response measures, but the success is limited to only a few regions. The rate of progress in the future will depend on a wide range of improved technologies and a continuous government monitoring for successful adoption of demand response programs to manage growing energy demand.
Li, Gaoming; Yi, Dali; Wu, Xiaojiao; Liu, Xiaoyu; Zhang, Yanqi; Liu, Ling; Yi, Dong
2015-01-01
Background Although a substantial number of studies focus on the teaching and application of medical statistics in China, few studies comprehensively evaluate the recognition of and demand for medical statistics. In addition, the results of these various studies differ and are insufficiently comprehensive and systematic. Objectives This investigation aimed to evaluate the general cognition of and demand for medical statistics by undergraduates, graduates, and medical staff in China. Methods We performed a comprehensive database search related to the cognition of and demand for medical statistics from January 2007 to July 2014 and conducted a meta-analysis of non-controlled studies with sub-group analysis for undergraduates, graduates, and medical staff. Results There are substantial differences with respect to the cognition of theory in medical statistics among undergraduates (73.5%), graduates (60.7%), and medical staff (39.6%). The demand for theory in medical statistics is high among graduates (94.6%), undergraduates (86.1%), and medical staff (88.3%). Regarding specific statistical methods, the cognition of basic statistical methods is higher than of advanced statistical methods. The demand for certain advanced statistical methods, including (but not limited to) multiple analysis of variance (ANOVA), multiple linear regression, and logistic regression, is higher than that for basic statistical methods. The use rates of the Statistical Package for the Social Sciences (SPSS) software and statistical analysis software (SAS) are only 55% and 15%, respectively. Conclusion The overall statistical competence of undergraduates, graduates, and medical staff is insufficient, and their ability to practically apply their statistical knowledge is limited, which constitutes an unsatisfactory state of affairs for medical statistics education. Because the demand for skills in this area is increasing, the need to reform medical statistics education in China has become urgent. PMID:26053876
Almonroeder, Thomas Gus; Kernozek, Thomas; Cobb, Stephen; Slavens, Brooke; Wang, Jinsung; Huddleston, Wendy
2018-05-01
Study Design Cross-sectional study. Background The drop vertical jump task is commonly used to screen for anterior cruciate ligament injury risk; however, its predictive validity is limited. The limited predictive validity of the drop vertical jump task may be due to not imposing the cognitive demands that reflect sports participation. Objectives To investigate the influence of additional cognitive demands on lower extremity mechanics during execution of the drop vertical jump task. Methods Twenty uninjured women (age range, 18-25 years) were required to perform the standard drop vertical jump task, as well as drop vertical jumps that included additional cognitive demands. The additional cognitive demands were related to attending to an overhead goal (ball suspended overhead) and/or temporal constraints on movement selection (decision making). Three-dimensional ground reaction forces and lower extremity mechanics were compared between conditions. Results The inclusion of the overhead goal resulted in higher peak vertical ground reaction forces and lower peak knee flexion angles in comparison to the standard drop vertical jump task. In addition, participants demonstrated greater peak knee abduction angles when trials incorporated temporal constraints on decision making and/or required participants to attend to an overhead goal, in comparison to the standard drop vertical jump task. Conclusion Imposing additional cognitive demands during execution of the drop vertical jump task influenced lower extremity mechanics in a manner that suggested increased loading of the anterior cruciate ligament. Tasks utilized in anterior cruciate ligament injury risk screening may benefit from more closely reflecting the cognitive demands of the sports environment. J Orthop Sports Phys Ther 2018;48(5):381-387. Epub 10 Jan 2018. doi:10.2519/jospt.2018.7739.
Wu, Yazhou; Zhou, Liang; Li, Gaoming; Yi, Dali; Wu, Xiaojiao; Liu, Xiaoyu; Zhang, Yanqi; Liu, Ling; Yi, Dong
2015-01-01
Although a substantial number of studies focus on the teaching and application of medical statistics in China, few studies comprehensively evaluate the recognition of and demand for medical statistics. In addition, the results of these various studies differ and are insufficiently comprehensive and systematic. This investigation aimed to evaluate the general cognition of and demand for medical statistics by undergraduates, graduates, and medical staff in China. We performed a comprehensive database search related to the cognition of and demand for medical statistics from January 2007 to July 2014 and conducted a meta-analysis of non-controlled studies with sub-group analysis for undergraduates, graduates, and medical staff. There are substantial differences with respect to the cognition of theory in medical statistics among undergraduates (73.5%), graduates (60.7%), and medical staff (39.6%). The demand for theory in medical statistics is high among graduates (94.6%), undergraduates (86.1%), and medical staff (88.3%). Regarding specific statistical methods, the cognition of basic statistical methods is higher than of advanced statistical methods. The demand for certain advanced statistical methods, including (but not limited to) multiple analysis of variance (ANOVA), multiple linear regression, and logistic regression, is higher than that for basic statistical methods. The use rates of the Statistical Package for the Social Sciences (SPSS) software and statistical analysis software (SAS) are only 55% and 15%, respectively. The overall statistical competence of undergraduates, graduates, and medical staff is insufficient, and their ability to practically apply their statistical knowledge is limited, which constitutes an unsatisfactory state of affairs for medical statistics education. Because the demand for skills in this area is increasing, the need to reform medical statistics education in China has become urgent.
Demand management and case management: a conservation strategy.
Bryant, C D R Anna K
2007-01-01
This article reviews the history and development of managed competition, and explores the possibilities of a new demand management strategy in the context of nurse case management to offer less costly, higher quality care for a greater number of patients. The article examines the history and principles of healthcare demand management, its implementation in the hospital and clinical practices of nurse case managers, and its impacts in reducing costs while maintaining care levels. The article develops and analyzes the conflicts and common ground between demand management and case management. First, demand-side strategies can be effective in reducing costs while maintaining quality of nursing care; second, nurse case managers should employ patient education, self-care, and staffing solutions to manage demand. Nurse case managers must apply demand management principles carefully. Their goal is not to restrict care, but to maintain the highest levels of care possible within the limits of their practice's resources and staffing. Two critical themes emerge: (1) demand management is a potential alternative to market-driven managed competition and (2) nursing case management can affect an effective form of demand management. However, the long-term implications of these nursing case management strategies on healthcare staffing need further exploration.
Oral literacy demand of preventive dental visits in a pediatric medical office: a pilot study.
Kranz, Ashley M; Pahel, Bhavna T; Rozier, R Gary
2013-01-01
The purpose of this study was to examine the oral literacy demands placed on parents of young children during preventive dental visits in a pediatric medical office. Transcripts of audio recordings for 15 pediatric medical visits were analyzed to assess the oral literacy demand of the visit, as measured by use of terminology, language complexity, and structural characteristics of the dialogue. Parent-completed surveys were used to determine recall of dental concepts discussed during the visit. Pearson's correlation coefficients were calculated to identify relationships among these measures and parental recall of the visit. Visits were interactive and used limited jargon and uncomplicated language. Oral literacy demand measures were associated with each other. Parental recall of the visit was associated with measures of high oral literacy demand. Assessing measures of oral literacy demand is a novel method for examining provider communication used during preventive dental visits in a pediatric medical office. Providers displayed low oral literacy demand when communicating with parents. Parental recall of dental concepts, however, was associated unexpectedly with higher oral literacy demand. Further research should examine a larger sample size and the effect of measures of oral literacy demand among low- and high-literacy patients.
The growing impact of lyophilized cell-free protein expression systems
Hunt, J. Porter; Yang, Seung Ook; Wilding, Kristen M.; Bundy, Bradley C.
2017-01-01
ABSTRACT Recently reported shelf-stable, on-demand protein synthesis platforms are enabling new possibilities in biotherapeutics, biosensing, biocatalysis, and high throughput protein expression. Lyophilized cell-free protein expression systems not only overcome cold-storage limitations, but also enable stockpiling for on-demand synthesis and completely sterilize the protein synthesis platform. Recently reported high-yield synthesis of cytotoxic protein Onconase from lyophilized E. coli extract preparations demonstrates the utility of lyophilized cell-free protein expression and its potential for creating on-demand biotherapeutics, vaccines, biosensors, biocatalysts, and high throughput protein synthesis. PMID:27791452
Intelligent transportation systems national investment and market analysis : executive summary
DOT National Transportation Integrated Search
1997-05-01
The United States transportation system is unparalleled. Yet, today, the system is straining to meet the growing demand for transportation. Planners are faced with increasing congestion, limited funds, equally limited rights-of-way, and concern fo...
Task Demands Control Acquisition and Storage of Visual Information
ERIC Educational Resources Information Center
Droll, Jason A.; Hayhoe, Mary M.; Triesch, Jochen; Sullivan, Brian T.
2005-01-01
Attention and working memory limitations set strict limits on visual representations, yet researchers have little appreciation of how these limits constrain the acquisition of information in ongoing visually guided behavior. Subjects performed a brick sorting task in a virtual environment. A change was made to 1 of the features of the brick being…
Time limits during visual foraging reveal flexible working memory templates.
Kristjánsson, Tómas; Thornton, Ian M; Kristjánsson, Árni
2018-06-01
During difficult foraging tasks, humans rarely switch between target categories, but switch frequently during easier foraging. Does this reflect fundamental limits on visual working memory (VWM) capacity or simply strategic choice due to effort? Our participants performed time-limited or unlimited foraging tasks where they tapped stimuli from 2 target categories while avoiding items from 2 distractor categories. These time limits should have no effect if capacity imposes limits on VWM representations but more flexible VWM could allow observers to use VWM according to task demands in each case. We found that with time limits, participants switched more frequently and switch-costs became much smaller than during unlimited foraging. Observers can therefore switch between complex (conjunction) target categories when needed. We propose that while maintaining many complex templates in working memory is effortful and observers avoid this, they can do so if this fits task demands, showing the flexibility of working memory representations used for visual exploration. This is in contrast with recent proposals, and we discuss the implications of these findings for theoretical accounts of working memory. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
Robust Unit Commitment Considering Uncertain Demand Response
Liu, Guodong; Tomsovic, Kevin
2014-09-28
Although price responsive demand response has been widely accepted as playing an important role in the reliable and economic operation of power system, the real response from demand side can be highly uncertain due to limited understanding of consumers' response to pricing signals. To model the behavior of consumers, the price elasticity of demand has been explored and utilized in both research and real practice. However, the price elasticity of demand is not precisely known and may vary greatly with operating conditions and types of customers. To accommodate the uncertainty of demand response, alternative unit commitment methods robust to themore » uncertainty of the demand response require investigation. In this paper, a robust unit commitment model to minimize the generalized social cost is proposed for the optimal unit commitment decision taking into account uncertainty of the price elasticity of demand. By optimizing the worst case under proper robust level, the unit commitment solution of the proposed model is robust against all possible realizations of the modeled uncertain demand response. Numerical simulations on the IEEE Reliability Test System show the e ectiveness of the method. Finally, compared to unit commitment with deterministic price elasticity of demand, the proposed robust model can reduce the average Locational Marginal Prices (LMPs) as well as the price volatility.« less
Task-dependent individual differences in prefrontal connectivity.
Biswal, Bharat B; Eldreth, Dana A; Motes, Michael A; Rypma, Bart
2010-09-01
Recent advances in neuroimaging have permitted testing of hypotheses regarding the neural bases of individual differences, but this burgeoning literature has been characterized by inconsistent results. To test the hypothesis that differences in task demands could contribute to between-study variability in brain-behavior relationships, we had participants perform 2 tasks that varied in the extent of cognitive involvement. We examined connectivity between brain regions during a low-demand vigilance task and a higher-demand digit-symbol visual search task using Granger causality analysis (GCA). Our results showed 1) Significant differences in numbers of frontoparietal connections between low- and high-demand tasks 2) that GCA can detect activity changes that correspond with task-demand changes, and 3) faster participants showed more vigilance-related activity than slower participants, but less visual-search activity. These results suggest that relatively low-demand cognitive performance depends on spontaneous bidirectionally fluctuating network activity, whereas high-demand performance depends on a limited, unidirectional network. The nature of brain-behavior relationships may vary depending on the extent of cognitive demand. High-demand network activity may reflect the extent to which individuals require top-down executive guidance of behavior for successful task performance. Low-demand network activity may reflect task- and performance monitoring that minimizes executive requirements for guidance of behavior.
Task-Dependent Individual Differences in Prefrontal Connectivity
Biswal, Bharat B.; Eldreth, Dana A.; Motes, Michael A.
2010-01-01
Recent advances in neuroimaging have permitted testing of hypotheses regarding the neural bases of individual differences, but this burgeoning literature has been characterized by inconsistent results. To test the hypothesis that differences in task demands could contribute to between-study variability in brain-behavior relationships, we had participants perform 2 tasks that varied in the extent of cognitive involvement. We examined connectivity between brain regions during a low-demand vigilance task and a higher-demand digit–symbol visual search task using Granger causality analysis (GCA). Our results showed 1) Significant differences in numbers of frontoparietal connections between low- and high-demand tasks 2) that GCA can detect activity changes that correspond with task-demand changes, and 3) faster participants showed more vigilance-related activity than slower participants, but less visual-search activity. These results suggest that relatively low-demand cognitive performance depends on spontaneous bidirectionally fluctuating network activity, whereas high-demand performance depends on a limited, unidirectional network. The nature of brain-behavior relationships may vary depending on the extent of cognitive demand. High-demand network activity may reflect the extent to which individuals require top-down executive guidance of behavior for successful task performance. Low-demand network activity may reflect task- and performance monitoring that minimizes executive requirements for guidance of behavior. PMID:20064942
Wilber, William G.; Peters, James G.; Crawford, Charles G.
1979-01-01
A digital model calibrated to conditions in East Fork White River, Bartholomew County, IN, was used to develop alternatives for future waste loadings that would be compatible with Indiana stream water-quality standards defined for two critical hydrologic conditions, summer and winter low flows. The model indicates that benthic-oxygen demand and the headwater concentrations of carbonaceous biochemical-oxygen demand, nitrogenous biochemical-oxygen demand, and dissolved oxygen are the most significant factors affecting the dissolved-oxygen concentration of East Fork White River downstream from the Columbus wastewater-treatment facility. The effect of effluent from the facility on the water quality of East Fork White River was minimal. The model also indicates that, with a benthic-oxygen demand of approximately 0.65 gram per square meter per day, the stream has no additional waste-load assimilative capacity during summer low flows. Regardless of the quality of the Columbus wastewater effluent, the minimum 24-hour average dissolved-oxygen concentration of at least 5 milligrams per liter, the State 's water-quality standard for streams, would not be met. Ammonia toxicity is not a limiting water-quality criterion during summer and winter low flows. During winter low flows, the current carbonaceous biochemical-oxygen demand limits for the Columbus wastewater-treatment facility will not result in violations of the in-stream dissolved-oxygen standard. (USGS)
Assessing long-term water demand of constantine province in Kébir-Rhumel Mediterranean catchment
NASA Astrophysics Data System (ADS)
Kiniouar, H.; Hani, A.; Younsi, A.
2017-02-01
By mid-century, in the southern Mediterranean countries, levies probably reach the limit level of renewable water resources. Algeria is one of the poorest countries in renewable water resources, with an annual storage capacity of 14.6 million m3 in the Mediterranean coastal watersheds, representing 7% of the land area and accounts for 90 % of total surface runoff of the country. In this paper, we assess water demand to meet the needs of water users in Constantine province. The latter is located in the Kébir-Rhumel Mediterranean basin under semi-arid climate with relatively high growth rate of population, agricultural and industrial activities. Using Water Evaluation And Planning system (WEAP), we built a model for managing water demand of Constantine province. A business as usual and five scenarii of «water demand " were calculated by WEAP model to simulate the uncertainties over the period of 20 years (2008-2027) : (1) Population growth, (2) increase in irrigated crop lands, (3) decrease in basic drinking water consumption, (4) decrease in basic irrigation water consumption and (5) increase in basic industrial water consumption. The results showed that scenario 3 is the best alternative scenario and the most efficient by reducing drinking water demand for about 12 Mm3 in 20 years, and thus preserve reaching the limits of water resources potentialities.
Resource Demand Scenarios for the Major Metals.
Elshkaki, Ayman; Graedel, T E; Ciacci, Luca; Reck, Barbara K
2018-03-06
The growth in metal use in the past few decades raises concern that supplies may be insufficient to meet demands in the future. From the perspective of historical and current use data for seven major metals-iron, manganese, aluminum, copper, nickel, zinc, and lead-we have generated several scenarios of potential metal demand from 2010 to 2050 under alternative patterns of global development. We have also compared those demands with various assessments of potential supply to midcentury. Five conclusions emerge: (1) The calculated demand for each of the seven metals doubles or triples relative to 2010 levels by midcentury; (2) The largest demand increases relate to a scenario in which increasingly equitable values and institutions prevail throughout the world; (3) The metal recycling flows in the scenarios meet only a modest fraction of future metals demand for the next few decades; (4) In the case of copper, zinc, and perhaps lead, supply may be unlikely to meet demand by about midcentury under the current use patterns of the respective metals; (5) Increased rates of demand for metals imply substantial new energy provisioning, leading to increases in overall global energy demand of 21-37%. These results imply that extensive technological transformations and governmental initiatives could be needed over the next several decades in order that regional and global development and associated metal demand are not to be constrained by limited metal supply.
Fabricate-On-Demand Vacuum Insulating Glazings
DOE Office of Scientific and Technical Information (OSTI.GOV)
McCamy, James W.
PPG proposed to design a fabricate-on-demand manufacturing process to overcome the cost and supply chain issues preventing widespread adoption of vacuum insulated glazing (VIG) units. To do so, we focused on improving three areas of VIG manufacturing that drive high costs and limit the ability for smaller manufacturers to enter the market: edge sealing, pillar design/placement, and evacuating the VIG.
Cut fossil fuel links and curb burden on the NHS.
Munro, Alice
2017-06-21
At a time when the NHS is struggling to meet demand, it is easy to regard the health impact of climate change as less urgent than the immediate needs of patients. However, action now to limit the effects of climate change would also reduce demands on the health service and help us to meet the healthcare needs of future generations.
NASA Astrophysics Data System (ADS)
Voisin, N.; Liu, L.; Hejazi, M.; Tesfa, T.; Li, H.; Huang, M.; Liu, Y.; Leung, L. R.
2013-11-01
An integrated model is being developed to advance our understanding of the interactions between human activities, terrestrial system and water cycle, and to evaluate how system interactions will be affected by a changing climate at the regional scale. As a first step towards that goal, a global integrated assessment model, which includes a water-demand model driven by socioeconomics at regional and global scales, is coupled in a one-way fashion with a land surface hydrology-routing-water resources management model. To reconcile the scale differences between the models, a spatial and temporal disaggregation approach is developed to downscale the annual regional water demand simulations into a daily time step and subbasin representation. The model demonstrates reasonable ability to represent the historical flow regulation and water supply over the US Midwest (Missouri, Upper Mississippi, and Ohio river basins). Implications for future flow regulation, water supply, and supply deficit are investigated using climate change projections with the B1 and A2 emission scenarios, which affect both natural flow and water demand. Although natural flow is projected to increase under climate change in both the B1 and A2 scenarios, there is larger uncertainty in the changes of the regulated flow. Over the Ohio and Upper Mississippi river basins, changes in flow regulation are driven by the change in natural flow due to the limited storage capacity. However, both changes in flow and demand have effects on the Missouri River Basin summer regulated flow. Changes in demand are driven by socioeconomic factors, energy and food demands, global markets and prices with rainfed crop demand handled directly by the land surface modeling component. Even though most of the changes in supply deficit (unmet demand) and the actual supply (met demand) are driven primarily by the change in natural flow over the entire region, the integrated framework shows that supply deficit over the Missouri River Basin sees an increasing sensitivity to changes in demand in future periods. It further shows that the supply deficit is six times as sensitive as the actual supply to changes in flow and demand. A spatial analysis of the supply deficit demonstrates vulnerabilities of urban areas located along mainstream with limited storage.
Estimating irrigation water demand in the Moroccan Drâa Valley using contingent valuation.
Storm, Hugo; Heckelei, Thomas; Heidecke, Claudia
2011-10-01
Irrigation water management is crucial for agricultural production and livelihood security in Morocco as in many other parts of the world. For the implementation of an effective water management, knowledge about farmers' demand for irrigation water is crucial to assess reactions to water pricing policy, to establish a cost-benefit analysis of water supply investments or to determine the optimal water allocation between different users. Previously used econometric methods providing this information often have prohibitive data requirements. In this paper, the Contingent Valuation Method (CVM) is adjusted to derive a demand function for irrigation water along farmers' willingness to pay for one additional unit of surface water or groundwater. An application in the Middle Drâa Valley in Morocco shows that the method provides reasonable results in an environment with limited data availability. For analysing the censored survey data, the Least Absolute Deviation estimator was found to be a more suitable alternative to the Tobit model as errors are heteroscedastic and non-normally distributed. The adjusted CVM to derive demand functions is especially attractive for water scarce countries under limited data availability. Copyright © 2011 Elsevier Ltd. All rights reserved.
Werner, Rachel M; Konetzka, R Tamara; Polsky, Daniel
2016-06-01
Limited consumer use of health care report cards may be due to the large amount of information presented in report cards, which can be difficult to understand. These limitations may be overcome with summary measures. Our objective was to evaluate consumer response to summary measures in the setting of nursing homes. 2005-2010 nursing home Minimum Data Set and Online Survey, Certification and Reporting (OSCAR) datasets. In December 2008, Medicare converted its nursing home report card to summary or star ratings. We test whether there was a change in consumer demand for nursing homes related to the nursing home's star rating after the information was released. The star rating system was associated with a significant change in consumer demand for low- and high-scoring facilities. After the star-based rating system was released, 1-star facilities typically lost 8 percent of their market share and 5-star facilities gained over 6 percent of their market share. The nursing home star rating system significantly affected consumer demand for high- and low-rated nursing homes. These results support the use of summary measures in report cards. © Health Research and Educational Trust.
Water demand forecasting: review of soft computing methods.
Ghalehkhondabi, Iman; Ardjmand, Ehsan; Young, William A; Weckman, Gary R
2017-07-01
Demand forecasting plays a vital role in resource management for governments and private companies. Considering the scarcity of water and its inherent constraints, demand management and forecasting in this domain are critically important. Several soft computing techniques have been developed over the last few decades for water demand forecasting. This study focuses on soft computing methods of water consumption forecasting published between 2005 and 2015. These methods include artificial neural networks (ANNs), fuzzy and neuro-fuzzy models, support vector machines, metaheuristics, and system dynamics. Furthermore, it was discussed that while in short-term forecasting, ANNs have been superior in many cases, but it is still very difficult to pick a single method as the overall best. According to the literature, various methods and their hybrids are applied to water demand forecasting. However, it seems soft computing has a lot more to contribute to water demand forecasting. These contribution areas include, but are not limited, to various ANN architectures, unsupervised methods, deep learning, various metaheuristics, and ensemble methods. Moreover, it is found that soft computing methods are mainly used for short-term demand forecasting.
NASA Astrophysics Data System (ADS)
Niaz, Mansoor
It has been shown that student performance in chemistry problems decreases as the M demand of the problem increases, thus emphasizing the role of information processing in problem solving. It was hypothesized that manipulation (increase or decrease) of the M demand of a problem can affect student performance. Increasing the M demand of a problem would affect more the performance of subjects with a limited functional M capacity. The objective of this study is to investigate the effect of manipulation (increase) of the M demand of chemistry problems, having the same logical structure, on performance of students having different functional M capacity, cognitive style, and formal operational reasoning patterns. As predicted the performance of one group of students was lower after the manipulation (increase) in the M demand of the problem. This shows how even small changes in the amount of information required for processing can lead to working memory overload, as a consequence of a poor capacity for mobilization of M power.
The Demands of Nuclear Safety: Mishaps and USSTRATCOM
2011-06-01
maintenance operation—the unexpected will occur. Scott D. Sagan On 30 August 2007 the unexpected occurred. Ironically, the safety problem did... Sagan , The Limits of Safety: Organizations, Accidents, and Nuclear Weapons (Princeton, NJ: Princeton University Press, 1993), 14, 48. 39 Sagan , Limits...1 Scott D. Sagan , The Limits of Safety: Organizations, Accidents, and Nuclear Weapons (Princeton, NJ: Princeton
End-User Tools Towards AN Efficient Electricity Consumption: the Dynamic Smart Grid
NASA Astrophysics Data System (ADS)
Kamel, Fouad; Kist, Alexander A.
2010-06-01
Growing uncontrolled electrical demands have caused increased supply requirements. This causes volatile electrical markets and has detrimental unsustainable environmental impacts. The market is presently characterized by regular daily peak demand conditions associated with high electricity prices. A demand-side response system can limit peak demands to an acceptable level. The proposed scheme is based on energy demand and price information which is available online. An online server is used to communicate the information of electricity suppliers to users, who are able to use the information to manage and control their own demand. A configurable, intelligent switching system is used to control local loads during peak events and mange the loads at other times as necessary. The aim is to shift end user loads towards periods where energy demand and therefore also prices are at the lowest. As a result, this will flatten the load profile and avoiding load peeks which are costly for suppliers. The scheme is an endeavour towards achieving a dynamic smart grid demand-side-response environment using information-based communication and computer-controlled switching. Diffusing the scheme shall lead to improved electrical supply services and controlled energy consumption and prices.
37 CFR 1.480 - Demand for international preliminary examination.
Code of Federal Regulations, 2010 CFR
2010-07-01
... been submitted (PCT Rule 54bis.1(b)). [52 FR 20048, May 28, 1987, as amended at 53 FR 47810, Nov. 28... (§ 1.482(a)(1)) and the handling fee (§ 1.482(b)) shall be due within the applicable time limit set forth in PCT Rule 57.3. (b) The Demand shall be made on a standardized form (PCT Rule 53). Copies of the...
37 CFR 1.480 - Demand for international preliminary examination.
Code of Federal Regulations, 2014 CFR
2014-07-01
... been submitted (PCT Rule 54bis.1(b)). [52 FR 20048, May 28, 1987, as amended at 53 FR 47810, Nov. 28... (§ 1.482(a)(1)) and the handling fee (§ 1.482(b)) shall be due within the applicable time limit set forth in PCT Rule 57.3. (b) The Demand shall be made on a standardized form (PCT Rule 53). Copies of the...
37 CFR 1.480 - Demand for international preliminary examination.
Code of Federal Regulations, 2012 CFR
2012-07-01
... been submitted (PCT Rule 54bis.1(b)). [52 FR 20048, May 28, 1987, as amended at 53 FR 47810, Nov. 28... (§ 1.482(a)(1)) and the handling fee (§ 1.482(b)) shall be due within the applicable time limit set forth in PCT Rule 57.3. (b) The Demand shall be made on a standardized form (PCT Rule 53). Copies of the...
37 CFR 1.480 - Demand for international preliminary examination.
Code of Federal Regulations, 2013 CFR
2013-07-01
... been submitted (PCT Rule 54bis.1(b)). [52 FR 20048, May 28, 1987, as amended at 53 FR 47810, Nov. 28... (§ 1.482(a)(1)) and the handling fee (§ 1.482(b)) shall be due within the applicable time limit set forth in PCT Rule 57.3. (b) The Demand shall be made on a standardized form (PCT Rule 53). Copies of the...
37 CFR 1.480 - Demand for international preliminary examination.
Code of Federal Regulations, 2011 CFR
2011-07-01
... been submitted (PCT Rule 54bis.1(b)). [52 FR 20048, May 28, 1987, as amended at 53 FR 47810, Nov. 28... (§ 1.482(a)(1)) and the handling fee (§ 1.482(b)) shall be due within the applicable time limit set forth in PCT Rule 57.3. (b) The Demand shall be made on a standardized form (PCT Rule 53). Copies of the...
Potential Impact of Bioenergy Demand on the Sustainability of the Southern Forest Resource
Karen L. Abt; Robert C. Abt
2012-01-01
The use of woody biomass for the production of domestic bioenergy to meet policy-driven demands could lead to significant changes in the forest resource. These impacts may be limited if woody biomass from forests is defined as only the residues from logging. Yet, if only residue is used, the contribution of woody biomass to a renewable energy portfolio will also be...
Change in the southern U.S. water demand and supply over the next forty years
Steven C. McNulty; Ge Sun; Erika C. Cohen; Jennifer A. Moore Myers
2008-01-01
Water shortages are often considered a problem in the western United States, where water supply is limited compared to the eastern half of the country. However, periodic water shortages are also common in the southeastern United States due to high water demand and periodic drought. Southeastern U.S. municipalities spend billions of dollars to develop water storage...
Hyperspectral imaging to identify salt-tolerant wheat lines
USDA-ARS?s Scientific Manuscript database
In order to address the worldwide growing demand for food, agriculture is facing certain challenges and limitations. One of the important threats limiting crop productivity is salinity. Identifying salt tolerate varieties is crucial to mitigate the negative effects of this abiotic stress in agricult...
Khatri, Krishan L; Tamil, Lakshman S
2018-01-01
Chronic respiratory diseases, mainly asthma and chronic obstructive pulmonary disease (COPD), affect the lives of people by limiting their activities in various aspects. Overcrowding of hospital emergency departments (EDs) due to respiratory diseases in certain weather and environmental pollution conditions results in the degradation of quality of medical care, and even limits its availability. A useful tool for ED managers would be to forecast peak demand days so that they can take steps to improve the availability of medical care. In this paper, we developed an artificial neural network based classifier using multilayer perceptron with back propagation algorithm that predicts peak event (peak demand days) of patients with respiratory diseases, mainly asthma and COPD visiting EDs in Dallas County of Texas in the United States. The precision and recall for peak event class were 77.1% and 78.0%, respectively, and those for nonpeak events were 83.9% and 83.2%, respectively. The overall accuracy of the system is 81.0%.
Smart Grid Constraint Violation Management for Balancing and Regulating Purposes
Bhattarai, Bishnu; Kouzelis, Konstantinos; Mendaza, Iker; ...
2017-03-29
The gradual active load penetration in low voltage distribution grids is expected to challenge their network capacity in the near future. Distribution system operators should for this reason resort to either costly grid reinforcements or to demand side management mechanisms. Since demand side management implementation is usually cheaper, it is also the favorable solution. To this end, this article presents a framework for handling grid limit violations, both voltage and current, to ensure a secure and qualitative operation of the distribution grid. This framework consists of two steps, namely a proactive centralized and subsequently a reactive decentralized control scheme. Themore » former is employed to balance the one hour ahead load while the latter aims at regulating the consumption in real-time. In both cases, the importance of fair use of electricity demand flexibility is emphasized. Thus, it is demonstrated that this methodology aids in keeping the grid status within preset limits while utilizing flexibility from all flexibility participants.« less
Zarriello, Phillip J.
2002-01-01
A Hydrologic Simulation Program FORTRAN (HSPF) model previously developed for the Ipswich River Basin was modified to simulate the hydrologic response and firm yields of the water-supply systems of Lynn, Peabody, and Salem-Beverly. The updated model, expanded to include a portion of the Saugus River Basin that supplies water to Lynn, simulated reservoir system storage over a 35-year period (1961-95) under permitted withdrawals and hypothetical restrictions designed to maintain seasonally varied streamflow for aquatic habitat. A firm yield was calculated for each system and each withdrawal restriction by altering demands until the system failed. This is considered the maximum withdrawal rate that satisfies demands, but depletes reservoir storage. Simulations indicate that, under the permitted withdrawals, Lynn and Salem-Beverly were able to meet demands and generally have their reservoir system recover to full capacity during most years; reservoir storage averaged 83 and 82 percent of capacity, respectively. The firm yields for the Lynn and Salem-Beverly systems were 11.4 and 12.2 million gallons per day (Mgal/d), respectively, or 8 and 21 percent more than average 1998-2000 demands, respectively. Under permitted withdrawals and average 1998-2000 demands, the Peabody system failed in all years; thus Peabody purchased water to meet demands. The firm yield for the Peabody system is 3.70 Mgal/d, or 37 percent less than the average 1998-2000 demand. Simulations that limit withdrawals to levels recommended by the Ipswich River Fisheries Restoration Task Group (IRFRTG) indicate that under average 1998-2000 demands, reservoir storage was depleted in each of the three systems. Reservoir storage under average 1998-2000 demands and IRFRTG-recommended streamflow requirements averaged 15, 22, and 71 percent of capacity for the Lynn, Peabody, Salem-Beverly systems, respectively. The firm-yield estimates under the IRFRTG-recommended streamflow requirements were 6.02, 1.94, and 7.69 Mgal/d or 43, 64, and 34 percent less than the average 1998-2000 demands for the Lynn, Peabody, and Salem-Beverly systems, respectively. Simulations that limit withdrawals from the Saugus River to a less stringent set of restrictions (based on an Instream Flow Incremental Methodology study) than those previously simulated indicate that the firm yield of the Lynn system is about 31 percent less than the average 1998-2000 withdrawals (7.31 Mgal/d).
Quantitative food web analysis supports the energy-limitation hypothesis in cave stream ecosystems.
Venarsky, Michael P; Huntsman, Brock M; Huryn, Alexander D; Benstead, Jonathan P; Kuhajda, Bernard R
2014-11-01
Energy limitation has long been the primary assumption underlying conceptual models of evolutionary and ecological processes in cave ecosystems. However, the prediction that cave communities are actually energy-limited in the sense that constituent populations are consuming all or most of their resource supply is untested. We assessed the energy-limitation hypothesis in three cave streams in northeastern Alabama (USA) by combining measurements of animal production, demand, and resource supplies (detritus, primarily decomposing wood particles). Comparisons of animal consumption and detritus supply rates in each cave showed that all, or nearly all, available detritus was required to support macroinvertebrate production. Furthermore, only a small amount of macroinvertebrate prey production remained to support other predatory taxa (i.e., cave fish and salamanders) after accounting for crayfish consumption. Placing the energy demands of a cave community within the context of resource supply rates provided quantitative support for the energy-limitation hypothesis, confirming the mechanism (limited energy surpluses) that likely influences the evolutionary processes and population dynamics that shape cave communities. Detritus-based surface ecosystems often have large detrital surpluses. Thus, cave ecosystems, which show minimal surpluses, occupy the extreme oligotrophic end of the spectrum of detritus-based food webs.
The Private Market for Long-Term Care Insurance in the U.S.: A Review of the Evidence
Brown, Jeffrey R.; Finkelstein, Amy
2009-01-01
This paper reviews the growing literature on the market for private long-term care insurance, a market notable for its small size despite the fact that long-term care expenses are potentially large and highly uncertain. After summarizing long-term care utilization and insurance coverage in the United States, the paper reviews research on the supply of and the demand for private long-term care insurance. It concludes that demand-side factors impose important limits on the size of the private market and that we currently have a limited understanding of how public policies could be designed to encourage the growth of this market. PMID:20046809
Engineering hurdles in contact and intraocular lens lathe design: the view ahead
NASA Astrophysics Data System (ADS)
Bradley, Norman D.; Keller, John R.; Ball, Gary A.
1994-05-01
Current trends in and intraocular lens design suggest ever- increasing demand for aspheric lens geometries - multisurface and/or toric surfaces - in a variety of new materials. As computer numeric controls (CNC) lathes and mills continue to evolve with he ophthalmic market, engineering hurdles present themselves to designers: Can hardware based upon single-point diamond turning accommodate the demands of software-driven designs? What are the limits of CNC resolution and repeatability in high-throughput production? What are the controlling factors in lathed, polish-free surface production? Emerging technologies in the lathed biomedical optics field are discussed along with their limitations, including refined diamond tooling, vibrational control, automation, and advanced motion control systems.
Water budget of the Calera Aquifer in Zacatecas, Mexico
USDA-ARS?s Scientific Manuscript database
In the Calera Aquifer Region of the State of Zacatecas, Mexico, limited rainfall and low agricultural water use efficiency in combination with fast growing industrial and urban water demand are contributing to groundwater depletion at an unsustainable rate. Limited data and planning tools were avail...
Walker, Nancy; Michaud, Kaleb; Wolfe, Frederick
2005-06-01
To describe workplace limitations and the validity and reliability of the Work Limitations Questionnaire (WLQ) in persons with rheumatoid arthritis (RA). A total of 836 employed persons with RA reported clinical and work related measures and completed the WLQ, a 25 item questionnaire that assesses the impact of chronic health conditions on job performance and productivity. Limitations are categorized into 4 domains: physical demands (PDS), mental demands (MDS), time management demands (TMS), and output demands (ODS), which are then used to calculate the WLQ index. Of the 836 completed WLQ, about 10% (85) could not be scored, as more than half the items in each domain were not applicable to the patient's job. Demographic and clinical variables were associated with missing WLQ scores including older age (OR 1.7, 95% CI 1.3-2.1), male sex (OR 1.9, 95% CI 1.2-3.0), and Health Assessment Questionnaire (HAQ) scores (OR 1.4, 95% CI 1.0-2.0). Work limitations were present in all work domains: PDS (27.5%), MDS (15.7%), ODS (19.4%), and TMS (28.6%), resulting in a mean WLQ index of 5.9 (SD 5.6), which corresponds to a 4.9% decrease in productivity and a 5.1% increase in work hours to compensate for productivity loss. The WLQ index was inversely associated with Medical Outcomes Study Short Form 36 (SF-36) Mental Component Score (MCS; r = -0.60) and Physical Component Score (PCS; r = -0.49). Fatigue (0.5), pain (0.46), and HAQ (0.56) were also significantly associated with the WLQ index. Weaker associations were seen with days unable to perform (0.29), days activities cut down (0.38), and annual income (-0.10). The WLQ is a reliable tool for assessing work productivity. However, persons with RA tend to select jobs that they can do with their RA limitations, with the result that the WLQ does not detect functional limitations as well as the HAQ and SF-36. The WLQ provides special information that is not available using conventional measures of assessment, and can provide helpful knowledge about individual patient problems in the workplace. Whether this information will have greater predictive ability and clinical relevance compared with surrogate measures such as the HAQ and SF-36 has not been determined, but should be the subject of future studies.
NASA Astrophysics Data System (ADS)
Flores, Robert Joseph
Distributed generation can provide many benefits over traditional central generation such as increased reliability and efficiency while reducing emissions. Despite these potential benefits, distributed generation is generally not purchased unless it reduces energy costs. Economic dispatch strategies can be designed such that distributed generation technologies reduce overall facility energy costs. In this thesis, a microturbine generator is dispatched using different economic control strategies, reducing the cost of energy to the facility. Several industrial and commercial facilities are simulated using acquired electrical, heating, and cooling load data. Industrial and commercial utility rate structures are modeled after Southern California Edison and Southern California Gas Company tariffs and used to find energy costs for the simulated buildings and corresponding microturbine dispatch. Using these control strategies, building models, and utility rate models, a parametric study examining various generator characteristics is performed. An economic assessment of the distributed generation is then performed for both the microturbine generator and parametric study. Without the ability to export electricity to the grid, the economic value of distributed generation is limited to reducing the individual costs that make up the cost of energy for a building. Any economic dispatch strategy must be built to reduce these individual costs. While the ability of distributed generation to reduce cost depends of factors such as electrical efficiency and operations and maintenance cost, the building energy demand being serviced has a strong effect on cost reduction. Buildings with low load factors can accept distributed generation with higher operating costs (low electrical efficiency and/or high operations and maintenance cost) due to the value of demand reduction. As load factor increases, lower operating cost generators are desired due to a larger portion of the building load being met in an effort to reduce demand. In addition, buildings with large thermal demand have access to the least expensive natural gas, lowering the cost of operating distributed generation. Recovery of exhaust heat from DG reduces cost only if the buildings thermal demand coincides with the electrical demand. Capacity limits exist where annual savings from operation of distributed generation decrease if further generation is installed. For low operating cost generators, the approximate limit is the average building load. This limit decreases as operating costs increase. In addition, a high capital cost of distributed generation can be accepted if generator operating costs are low. As generator operating costs increase, capital cost must decrease if a positive economic performance is desired.
U.S. Hardwood Product Exports to Canada and a Look at U.S. Hardwood Resources
Philip A. Araman
1998-01-01
Canada became the largest market for primary product hardwood exports in 1987 after slipping to No. 3 in 1986. Preferences for fine hardwoods and limited Canadian supplies of species such as oak should assure continued strong demands for U.S. hardwoods. Another reason for continued strong demand is that some Canadian firms process U.S. lumber and logs for export. This...
Work Characteristics Associated with Physical Functioning in Women
Palumbo, Aimee J.; De Roos, Anneclaire J.; Cannuscio, Carolyn; Robinson, Lucy; Mossey, Jana; Weitlauf, Julie; Garcia, Lorena; Wallace, Robert; Michael, Yvonne
2017-01-01
Women make up almost half of the labor force with older women becoming a growing segment of the population. Work characteristics influence physical functioning and women are at particular risk for physical limitations. However, little research has explored the effects of work characteristics on women’s physical functioning. U.S. women between the ages of 50 and 79 were enrolled in the Women’s Health Initiative Observational Study between 1993 and 1998. Women provided job titles and years worked at their three longest-held jobs (n = 79,147). Jobs were linked to characteristics in the Occupational Information Network. Three categories of job characteristics related to substantive complexity, physical demand, and social collaboration emerged. The association between job characteristics and physical limitations in later life, measured using a SF-36 Physical Functioning score <25th percentile, was examined using modified Poisson regression. After controlling for confounding variables, high physical demand was positively associated with physical limitations (RR = 1.09 CI: 1.06–1.12) and substantively complex work was negatively associated (RR = 0.94, CI: 0.91–0.96). Jobs requiring complex problem solving, active learning, and critical thinking were associated with better physical functioning. Employers should explore opportunities to reduce strain from physically demanding jobs and incorporate substantively complex tasks into women’s work to improve long-term health. PMID:28420131
Crawford, Charles G.; Wilber, William G.; Peters, James G.
1979-01-01
The Indiana State Board of Health is developing a water-quality management plan that includes establishing limits for wastewater effluents discharged into Indiana streams. A digital model calibrated to conditions in Wildcat Creek was used to predict alternatives for future waste loadings that would be compatible with Indiana stream water-quality standards defined for two critical hydrologic conditions, summer and winter low flows. The model indicates that benthic-oxygen demand is the most significant factor affecting the dissolved-oxygen concentrations in Wildcat Creek during summer low flows. The Indiana stream dissolved-oxygen standard should not be violated if the Kokomo wastewater-treatment facility meets its current National Pollution Discharge Elimination System permit restrictions (average monthly 5-day biochemical-oxygen demand of 5 milligrams per liter and maximum weekly 5-day biochemical-oxygen demand of 7.5 milligrams per liter) and benthic-oxygen demand becomes negligible. Ammonia-nitrogen toxicity may also be a water-quality limitation in Wildcat Creek. Ammonia-nitrogen waste loads for the Kokomo wastewater-treatment facility, projected by the Indiana State Board of Health, will result in stream ammonia-nitrogen concentrations that exceed the State standard (2.5 milligrams per liter during summer months and 4.0 milligrams per liter during winter months). (Kosco-USGS)
Work reintegration and cardiovascular disease: medical and rehabilitation influences.
O'Hagan, F T; Coutu, M F; Thomas, S G; Mertens, D J
2012-06-01
Research into work reintegration following cardiovascular disease onset is limited in its clinical and individual focus. There is no research examining worker experience in context during the return to work process. Qualitative case study method informed by applied ethnography. Worker experience was assessed through longitudinal in-depth interviews with 12 workers returning to work following disabling cardiac illness. Workplace context (Canadian auto manufacturing plant) was assessed through site visits and meetings with stakeholders including occupational health personnel. Data was analyzed using constant comparison and progressive coding. Twelve men (43-63 years) participated in the study. Results revealed that unyielding production demands and performance monitoring pushed worker capacities and caused "insidious stress". Medical reassurance was important in the workers' decisions to return to work and stay on the job but medical restrictions were viewed as having limited relevance owing to limited understanding of work demands. Medical sanction was important for transient absence from the workplace as well as permanent disability. Cardiac rehabilitation programs were beneficial for lifestyle modification and building exercise capacity, but had limited benefit on work reintegration. Occupational health provided monitoring and support during work reintegration. Medical reassurance can be an important influence on worker representations of disease threat. Medical advice as it pertained to work activities was less valued as it lacked considerations of work conditions. Cardiac rehabilitation lacked intensity and relevance to work demands. Occupational health was reassuring for workers and played an important role in developing return to work plans.
Hydrodynamics of isohydric and anisohydric trees: insights from models and measurements
NASA Astrophysics Data System (ADS)
Novick, K. A.; Oishi, A. C.; Roman, D. T.; Benson, M. C.; Miniat, C.
2016-12-01
In an effort to understand and predict the mechanisms that govern tree response to hydrologic stress, plant hydraulic theory, which classifies trees along a continuum of isohydric to anisohydric water use strategies, is increasingly being used. Isohydry maintains relatively constant leaf water potential during periods of water stress, promoting wide hydraulic safety margins that reduce the risk of xylem cavitation. In contrast, anisohydry allows leaf water potential to fall as soil water potential falls, but in doing so trees incur a greater risk of hydraulic failure. As a result, unique patterns of stomatal functioning between isohydric and anisohydric species are both predicted and observed in leaf-, tree-, and stand-level water use. We use a novel model formulation to examine the dynamics of three mechanisms that are potentially limiting to leaf-level gas exchange in trees during drought: (1) a `demand limitation' driven by an assumption of stomatal optimization of water loss and carbon uptake; (2) `hydraulic limitation' of water movement from the roots to the leaves; and (3) `non-stomatal' limitations imposed by declining leaf water status within the leaf. Model results suggest that species-specific `economics' of stomatal behavior may play an important role in differentiating species along the continuum of isohydric to anisohydric behavior; specifically, we show that non-stomatal and demand limitations may reduce stomatal conductance and increase leaf water potential, promoting wide safety margins characteristic of isohydric species. Direct comparisons of modeled and measured stomatal conductance further indicated that non-stomatal and demand limitations reproduced observed patterns of tree water use well for an isohydric species but that a hydraulic limitation likely applies in the case of an anisohydric species. This modeling framework used in concert with climate data may help land managers and scientists predict when and what forest species and communities might undergo drought-related mortality.
Unmet contraceptive need among married Nigerian women: an examination of trends and drivers.
Austin, Anne
2015-01-01
The aim of this study is to examine trends in and drivers of unmet need for contraceptives among married Nigerian women between 2003 and 2013. This analysis utilized combined data from the 2003, 2008 and 2013 cross-sectional Nigerian Demographic Health Surveys, resulting in a sample size of 54,873 currently married women. Multinomial logistic regression examined associations between trends in unmet need for spacing and limiting, and the demographic, socioeconomic, and reproductive profiles of the respondents. Women in 2008 were 30% more likely to have an unmet need for spacing, relative to women in 2013. Despite these significant declines in unmet need to space fertility between 2008 and 2013, the adjusted results show that between 2003 and 2013, there was no significant change in the trends in unmet need to space fertility. Unmet need to limit fertility was significantly higher in 2003, adjusted, and 2008 relative to 2013. Younger, low-parity, Muslim women were significantly less likely than older, high-parity, non-Muslim women to have an unmet need to limit fertility. Women residing in the northeast and northwest of the country were significantly less likely than women residing in the south of the country to have an unmet need to limit fertility. Women whose most recent child had died were significantly less likely to have an unmet need to space and limit fertility. These data suggest that interventions to increase the knowledge of modern contraceptives, to reduce child mortality, and to improve women's decision-making power would all serve to increase demand for contraceptives, even in areas with high-fertility preferences. Nigeria has set a goal of a 36% contraceptive prevalence rate by 2018. With a current contraceptive prevalence rate of 15% reaching the additional 16% of women, who have articulated a demand for contraception, will almost reach that goal. Contraceptive use directly reduces maternal risk; implementing interventions to increase demand for contraception and meeting articulated demands for contraception would not only support women's (and men's) ability to realize their reproductive rights but also, ultimately, may reduce the burden of maternal deaths in Nigeria. Copyright © 2014 The Author. Published by Elsevier Inc. All rights reserved.
Job demands, job resources, and work engagement of Japanese employees: a prospective cohort study.
Inoue, Akiomi; Kawakami, Norito; Tsuno, Kanami; Shimazu, Akihito; Tomioka, Kimiko; Nakanishi, Mayuko
2013-05-01
Research on the prospective association of job demands and job resources with work engagement is still limited in Asian countries, such as Japan. The purpose of the present study was to investigate the prospective association of job demands (i.e., psychological demands and extrinsic effort) and job resources (i.e., decision latitude, supervisor support, co-worker support, and extrinsic reward), based on the job demands-control (JD-C) [or demand-control-support (DCS)] model and the effort-reward imbalance (ERI) model, with work engagement among Japanese employees. The participants included 423 males and 672 females from five branches of a manufacturing company in Japan. Self-administered questionnaires, including the Job Content Questionnaire (JCQ), the Effort-Reward Imbalance Questionnaire (ERIQ), the nine-item Utrecht Work Engagement Scale (UWES-9), and demographic characteristics, were administered at baseline (August 2009). At one-year follow-up (August 2010), the UWES-9 was used again to assess work engagement. Hierarchical multiple regression analyses were conducted. After adjusting for demographic characteristics and work engagement at baseline, higher psychological demands and decision latitude were positively and significantly associated with greater work engagement at follow-up (β = 0.054, p = 0.020 for psychological demands and β = 0.061, p = 0.020 for decision latitude). Having higher psychological demands and decision latitude may enhance work engagement among Japanese employees.
76 FR 18620 - Operating Limitations at John F. Kennedy International Airport
Federal Register 2010, 2011, 2012, 2013, 2014
2011-04-04
.... Kennedy International Airport (JFK) that published on January 18, 2008, and was amended on February 14... rulemaking. Background Until recently, most operations at JFK took place during relatively pronounced arrival... limited the number of arrivals and departures at JFK during the peak afternoon demand period through the...
A remote sensing-based dry and wet limit-reference evapotranspiration model for water use monitoring
USDA-ARS?s Scientific Manuscript database
With increasing growth in human population, the demand for greater food production has exceeded the capability to provide a sustainable water supply for agriculture. This is exacerbated in areas suffering from prolonged drought conditions, particularly in water limited regions. Improving the managem...
Quality Characteristics of Soft Kernel Durum -- A New Cereal Crop
USDA-ARS?s Scientific Manuscript database
Production of crops is in part limited by consumer demand and utilization. In this regard, world production of durum wheat (Triticum turgidum subsp. durum is limited by its culinary uses. The leading constraint is its very hard kernels. Puroindolines, which act to soften the endosperm, are completel...
Interdisciplinary Educational Approaches to Promote Team-Based Geriatrics and Palliative Care
ERIC Educational Resources Information Center
Howe, Judith L.; Sherman, Deborah Witt
2006-01-01
Despite the increasing public demand for enhanced care of older patients and those with life-threatening illness, health professionals have had limited formal education in geriatrics and palliative care. Furthermore, formal education in interdisciplinary team training is limited. In order to remedy this situation, proactive interventions are being…
NASA Astrophysics Data System (ADS)
Huang, Yeu-Shiang; Wang, Ruei-Pei; Ho, Jyh-Wen
2015-07-01
Due to the constantly changing business environment, producers often have to deal with customers by adopting different procurement policies. That is, manufacturers confront not only predictable and regular orders, but also unpredictable and irregular orders. In this study, from the perspective of upstream manufacturers, both regular and irregular orders are considered in coping with the situation in which an uncertain demand is faced by the manufacturer, and a capacity confirming mechanism is used to examine such demand. If the demand is less than or equal to the capacity of the ordinary production channel, the general supply channel is utilised to fully account for the manufacturing process, but if the demand is greater than the capacity of the ordinary production channel, the contingency production channel would be activated along with the ordinary channel to satisfy the upcoming high demand. Besides, the reproductive property of the probability distribution is employed to represent the order quantity of the two types of demand. Accordingly, the optimal production rates and lot sizes for both channels are derived to provide managers with insights for further production planning.
A Risk Management Method for the Operation of a Supply-Chain without Storage:
NASA Astrophysics Data System (ADS)
Kobayashi, Yasuhiro; Manabe, Yuuji; Nakata, Norimasa; Kusaka, Satoshi
A business risk management method has been developed for a supply-chain without a storage function under demand uncertainty. Power supply players in the deregulated power market face the need to develop the best policies for power supply from self-production and reserved purchases to balance demand, which is predictable with error. The proposed method maximizes profit from the operation of the supply-chain under probabilistic demand uncertainty on the basis of a probabilistic programming approach. Piece-wise linear functions are employed to formulate the impact of under-booked or over-booked purchases on the supply cost, and constraints on over-demand probability are introduced to limit over-demand frequency on the basis of the demand probability distribution. The developed method has been experimentally applied to the supply policy of a power-supply-chain, the operation of which is based on a 3-stage pricing purchase contract and on 28 time zones. The characteristics of the obtained optimal supply policy are successfully captured in the numerical results, which suggest the applicability of the proposed method.
Area Under the Curve as a Novel Metric of Behavioral Economic Demand for Alcohol
Amlung, Michael; Yurasek, Ali; McCarty, Kayleigh N.; MacKillop, James; Murphy, James G.
2015-01-01
Behavioral economic purchase tasks can be readily used to assess demand for a number of addictive substances including alcohol, tobacco and illicit drugs. However, several methodological limitations associated with the techniques used to quantify demand may reduce the utility of demand measures. In the present study, we sought to introduce area under the curve (AUC), commonly used to quantify degree of delay discounting, as a novel index of demand. A sample of 207 heavy drinking college students completed a standard alcohol purchase task and provided information about typical weekly drinking patterns and alcohol-related problems. Level of alcohol demand was quantified using AUC – which reflects the entire amount of consumption across all drink prices - as well as the standard demand indices (e.g., intensity, breakpoint, Omax, Pmax, and elasticity). Results indicated that AUC was significantly correlated with each of the other demand indices (rs = .42–.92), with particularly strong associations with Omax (r = .92). In regression models, AUC and intensity were significant predictors of weekly drinking quantity and AUC uniquely predicted alcohol-related problems, even after controlling for drinking level. In a parallel set of analyses, Omax also predicted drinking quantity and alcohol problems, although Omax was not a unique predictor of the latter. These results offer initial support for using AUC as an index of alcohol demand. Additional research is necessary to further validate this approach and to examine its utility in quantifying demand for other addictive substances such as tobacco and illicit drugs. PMID:25895013
de Croon, E M; Blonk, R; de Zwart, B C H; Frings-Dresen, M; Broersen, 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. Methods: From 1181 lorry drivers (adjusted response 63%) self reported information was gathered by questionnaire on the independent variables (job control, quantitative workload, physical demands, and supervisor demands) and the dependent variables (fatigue and job dissatisfaction). Stepwise multiple regression analyses were performed to examine the main effects of job demands and job control and the interaction effect between job control and job demands on fatigue and job dissatisfaction. Results: The inclusion of physical and supervisor demands in the JD-C model explained a significant amount of variance in fatigue (3%) and job dissatisfaction (7%) over and above job control and quantitative workload. Moreover, in accordance with Karasek's interaction hypothesis, job control buffered the positive relation between quantitative workload and job dissatisfaction. Conclusions: Despite methodological limitations, the results suggest that the inclusion of (occupation) specific job control and job demand measures is a fruitful elaboration of the JD-C model. The occupation specific JD-C model gives occupational stress researchers better insight into the relation between the psychosocial work environment and wellbeing. Moreover, the occupation specific JD-C model may give practitioners more concrete and useful information about risk factors in the psychosocial work environment. Therefore, this model may provide points of departure for effective stress reducing interventions at work. PMID:12040108
Two-and-a-half-year-olds succeed at a traditional false-belief task with reduced processing demands.
Setoh, Peipei; Scott, Rose M; Baillargeon, Renée
2016-11-22
When tested with traditional false-belief tasks, which require answering a standard question about the likely behavior of an agent with a false belief, children perform below chance until age 4 y or later. When tested without such questions, however, children give evidence of false-belief understanding much earlier. Are traditional tasks difficult because they tap a more advanced form of false-belief understanding (fundamental-change view) or because they impose greater processing demands (processing-demands view)? Evidence that young children succeed at traditional false-belief tasks when processing demands are reduced would support the latter view. In prior research, reductions in inhibitory-control demands led to improvements in young children's performance, but often only to chance (instead of below-chance) levels. Here we examined whether further reductions in processing demands might lead to success. We speculated that: (i) young children could respond randomly in a traditional low-inhibition task because their limited information-processing resources are overwhelmed by the total concurrent processing demands in the task; and (ii) these demands include those from the response-generation process activated by the standard question. This analysis suggested that 2.5-y-old toddlers might succeed at a traditional low-inhibition task if response-generation demands were also reduced via practice trials. As predicted, toddlers performed above chance following two response-generation practice trials; toddlers failed when these trials either were rendered less effective or were used in a high-inhibition task. These results support the processing-demands view: Even toddlers succeed at a traditional false-belief task when overall processing demands are reduced.
de Croon, E M; Blonk, R W B; de Zwart, B C H; Frings-Dresen, M H W; Broersen, J P J
2002-06-01
Building on Karasek's model of job demands and control (JD-C model), this study examined the effects of job control, quantitative workload, and two occupation specific job demands (physical demands and supervisor demands) on fatigue and job dissatisfaction in Dutch lorry drivers. From 1181 lorry drivers (adjusted response 63%) self reported information was gathered by questionnaire on the independent variables (job control, quantitative workload, physical demands, and supervisor demands) and the dependent variables (fatigue and job dissatisfaction). Stepwise multiple regression analyses were performed to examine the main effects of job demands and job control and the interaction effect between job control and job demands on fatigue and job dissatisfaction. The inclusion of physical and supervisor demands in the JD-C model explained a significant amount of variance in fatigue (3%) and job dissatisfaction (7%) over and above job control and quantitative workload. Moreover, in accordance with Karasek's interaction hypothesis, job control buffered the positive relation between quantitative workload and job dissatisfaction. Despite methodological limitations, the results suggest that the inclusion of (occupation) specific job control and job demand measures is a fruitful elaboration of the JD-C model. The occupation specific JD-C model gives occupational stress researchers better insight into the relation between the psychosocial work environment and wellbeing. Moreover, the occupation specific JD-C model may give practitioners more concrete and useful information about risk factors in the psychosocial work environment. Therefore, this model may provide points of departure for effective stress reducing interventions at work.
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.
Escribà-Agüir, V; Tenías-Burillo, J M
2004-08-01
This study investigates the effect of gender role and the psychosocial work environment on the psychological well-being of hospital staff in two general hospitals in the province of Valencia (Spain). A cross-sectional survey was carried out among 313 workers by means of a self-answered questionnaire. The outcome variable (psychological well-being) was evaluated with four dimensions of the "SF-36 Health Survey" (mental health, vitality, limitations in the emotional role and limitations in the social function). The explanatory variables were: characteristics related to gender role, professional characteristics and the psychosocial working environment evaluated according to Karasek and Johnson's demand-control-support model. The adjusted odds ratios (ORs) and their 95% confidence intervals were calculated by logistical regression. Those who have very good marital relationship have less risk of presenting bad mental health, OR 0.43 (0.24-0.78), and limitation in the social function, OR 0.43 (0.24-0.77), and in the emotional role, OR 0.35 (0.16-0.74). Those who dedicate more than 30 h a week to domestic chores have a higher risk of limitation of social function, OR 2.48 (1.16-5.31). Those exposed to high psychological demands present a higher probability of having bad mental health, OR 1.77 (1.04-3.00). Those exposed to low job social support have a higher risk of bad mental health, OR 1.86 (1.09-3.19), low vitality, OR 2.21 (1.30-3.77), and limitation in the social function, OR 1.88 (1.10-3.22). Gender role and psychosocial work environment have a negative influence on the psychological well-being of hospital staff.
Wagner, Brian J.; Gannett, Marshall W.
2014-01-01
The water resources of the upper Klamath Basin, in southern Oregon and northern California, are managed to achieve various complex and interconnected purposes. Since 2001, irrigators in the Bureau of Reclamation Klamath Irrigation Project (Project) have been required to limit surface-water diversions to protect habitat for endangered freshwater and anadromous fishes. The reductions in irrigation diversions have led to an increased demand for groundwater by Project irrigators, particularly in drought years. The potential effects of sustained pumping on groundwater and surface-water resources have caused concern among Federal and state agencies, Indian tribes, wildlife groups, and groundwater users. To aid in the development of a viable groundwater-management strategy for the Project, the U.S. Geological Survey, in collaboration with the Klamath Water and Power Agency and the Oregon Water Resources Department, developed a groundwater-management model that links groundwater simulation with techniques of constrained optimization. The overall goal of the groundwater-management model is to determine the patterns of groundwater pumping that, to the extent possible, meet the supplemental groundwater demands of the Project. To ensure that groundwater development does not adversely affect groundwater and surface-water resources, the groundwater-management model includes constraints to (1) limit the effects of groundwater withdrawal on groundwater discharge to streams and lakes that support critical habitat for fish listed under the Endangered Species Act, (2) ensure that drawdowns do not exceed limits allowed by Oregon water law, and (3) ensure that groundwater withdrawal does not adversely affect agricultural drain flows that supply a substantial portion of water for irrigators and wildlife refuges in downslope areas of the Project. Groundwater-management alternatives were tested and designed within the framework of the Klamath Basin Restoration Agreement (currently [2013] awaiting authorizing Federal legislation), which would establish a permanent limit on the amount of surface water that can be diverted annually to the Project. Groundwater-management scenarios were evaluated for the period 1970•2004; supplemental groundwater demand by the Project was estimated as the part of irrigation demand that would not have been satisfied by the surface-water diversion allowed under the Klamath Basin Restoration Agreement. Over the 35-year management period, 22 years have supplemental groundwater demand, which ranges from a few thousand acre-feet (acre-ft) to about 100,000 acre-ft in the driest years. The results of the groundwater-management model indicate that supplemental groundwater pumping by the Project can be managed to avoid adverse effects to groundwater discharge that supports critical aquatic habitat. The existing configuration of wells in the Project would be able to meet groundwater-pumping goals in 14 of the 22 years with supplemental groundwater demand; however, substantial irrigation shortages can be expected during drought periods when the demand for supplemental groundwater is highest. The maximum irrigation-season withdrawal calculated by the groundwater-management model is about 60,000 acre-ft, the average withdrawal in drought years is about 54,000 acre-ft, and the amount of unmet groundwater demand reaches a maximum of about 45,000 acre-ft. A comparison of optimized groundwater withdrawals by geographic region shows that the highest annual withdrawals are associated with wells in the Tule Lake and Klamath Valley regions of the Project. The patterns of groundwater withdrawal also show that a substantial amount of the available pumping capacity is unused due to the restrictions imposed by drawdown constraints. Subsequent model applications were used to evaluate the sensitivity of optimization results to various factors. A sensitivity analysis quantified the changes in optimized groundwater withdrawals that result from changes in drawdown-constraint limits. The analysis showed the potential for substantial increases in withdrawals of groundwater with less restrictive drawdown limits at drawdown-control sites in the California part of the model. Systematic variation of the drains-constraint limit yielded a trade-off curve between optimized groundwater withdrawals and the allowable reduction in groundwater discharge to the Project drain system. Additional model applications were used to assess the value of increasing the pumping capacity of the network of wells serving the Project, and the relation between reduced off-Project groundwater pumping and increased pumping by Project irrigators.
Evaluation of Air Force and Navy Demand Forecasting Systems
1994-01-01
forecasting approach, the Air Force Material Command is questioning the adoption of the Navy’s Statistical Demand Forecasting System ( Gitman , 1994). The...Recoverable Item Process in the Requirements Data Bank System is to manage reparable spare parts ( Gitman , 1994). Although RDB will have the capability of...D062) ( Gitman , 1994). Since a comparison is made to address Air Force concerns, this research only limits its analysis to the range of Air Force
A global food demand model for the assessment of complex human-earth systems
DOE Office of Scientific and Technical Information (OSTI.GOV)
EDMONDS, JAMES A.; LINK, ROBERT; WALDHOFF, STEPHANIE T.
Demand for agricultural products is an important problem in climate change economics. Food consumption will shape and shaped by climate change and emissions mitigation policies through interactions with bioenergy and afforestation, two critical issues in meeting international climate goals such as two-degrees. We develop a model of food demand for staple and nonstaple commodities that evolves with changing incomes and prices. The model addresses a long-standing issue in estimating food demands, the evolution of demand relationships across large changes in income and prices. We discuss the model, some of its properties and limitations. We estimate parameter values using pooled cross-sectional-time-seriesmore » observations and the Metropolis Monte Carlo method and cross-validate the model by estimating parameters using a subset of the observations and test its ability to project into the unused observations. Finally, we apply bias correction techniques borrowed from the climate-modeling community and report results.« less
Chicago's water market: Dynamics of demand, prices and scarcity rents
Ipe, V.C.; Bhagwat, S.B.
2002-01-01
Chicago and its suburbs are experiencing an increasing demand for water from a growing population and economy and may experience water scarcity in the near future. The Chicago metropolitan area has nearly depleted its groundwater resources to a point where interstate conflicts with Wisconsin could accompany an increased reliance on those sources. Further, the withdrawals from Lake Michigan is limited by the Supreme Court decree. The growing demand and indications of possible scarcity suggest a need to reexamine the pricing policies and the dynamics of demand. The study analyses the demand for water and develops estimates of scarcity rents for water in Chicago. The price and income elasticities computed at the means are -0.002 and 0.0002 respectively. The estimated scarcity rents ranges from $0.98 to $1.17 per thousand gallons. The results indicate that the current prices do not fully account for the scarcity rents and suggest a current rate with in the range $1.53 to $1.72 per thousand gallons.
TePoel, Megan; Rohlman, Diane; Shaw, Meagan
2017-04-26
Hispanic farmworkers experience hazardous work conditions, language barriers, poverty, and limited healthcare access that increase their risk for health problems. We sought to characterize occupational and lifestyle stressors in farmworker couples and to examine the impact of seasonal work demand and gender on health outcomes. We administered surveys to 31 couples (N = 62) in May (low work demand) and September (high work demand) of 2012. Measures included acculturation, perceived stress, depressive symptoms, quality of life, decision latitude, support (supervisor, co-worker), and work-family conflict. This population did not report significant differences in stress in low and high work demand times. Women reported more work-family conflict (F = 19.06, p 0.0001; F = 11.28, p = 0.0015) and less supervisor support (F = 6.56, p = 0.0135). Women experienced more conflict between work and family and less support at work. This group reported low depressive symptomology and moderate levels of stress; a subset reported elevated levels. Copyright© by the American Society of Agricultural Engineers.
Duan, Jinli; Jiao, Feng; Zhang, Qishan; Lin, Zhibin
2017-08-06
The sharp increase of the aging population has raised the pressure on the current limited medical resources in China. To better allocate resources, a more accurate prediction on medical service demand is very urgently needed. This study aims to improve the prediction on medical services demand in China. To achieve this aim, the study combines Taylor Approximation into the Grey Markov Chain model, and develops a new model named Taylor-Markov Chain GM (1,1) (T-MCGM (1,1)). The new model has been tested by adopting the historical data, which includes the medical service on treatment of diabetes, heart disease, and cerebrovascular disease from 1997 to 2015 in China. The model provides a predication on medical service demand of these three types of disease up to 2022. The results reveal an enormous growth of urban medical service demand in the future. The findings provide practical implications for the Health Administrative Department to allocate medical resources, and help hospitals to manage investments on medical facilities.
A genetic-algorithm-based remnant grey prediction model for energy demand forecasting.
Hu, Yi-Chung
2017-01-01
Energy demand is an important economic index, and demand forecasting has played a significant role in drawing up energy development plans for cities or countries. As the use of large datasets and statistical assumptions is often impractical to forecast energy demand, the GM(1,1) model is commonly used because of its simplicity and ability to characterize an unknown system by using a limited number of data points to construct a time series model. This paper proposes a genetic-algorithm-based remnant GM(1,1) (GARGM(1,1)) with sign estimation to further improve the forecasting accuracy of the original GM(1,1) model. The distinctive feature of GARGM(1,1) is that it simultaneously optimizes the parameter specifications of the original and its residual models by using the GA. The results of experiments pertaining to a real case of energy demand in China showed that the proposed GARGM(1,1) outperforms other remnant GM(1,1) variants.
A genetic-algorithm-based remnant grey prediction model for energy demand forecasting
2017-01-01
Energy demand is an important economic index, and demand forecasting has played a significant role in drawing up energy development plans for cities or countries. As the use of large datasets and statistical assumptions is often impractical to forecast energy demand, the GM(1,1) model is commonly used because of its simplicity and ability to characterize an unknown system by using a limited number of data points to construct a time series model. This paper proposes a genetic-algorithm-based remnant GM(1,1) (GARGM(1,1)) with sign estimation to further improve the forecasting accuracy of the original GM(1,1) model. The distinctive feature of GARGM(1,1) is that it simultaneously optimizes the parameter specifications of the original and its residual models by using the GA. The results of experiments pertaining to a real case of energy demand in China showed that the proposed GARGM(1,1) outperforms other remnant GM(1,1) variants. PMID:28981548
Returning migrant characteristics and labor market demand in Greece.
Petras, E M; Kousis, M
1988-01-01
Immigrants who repatriate bring with them modern work skills which many observers in labor exporting regions describe as a great contribution to the mother country. Using data from 2 samples of Greek repatriates as well as projections of industrial labor force demands in Greece for the 1980s, this article challenges this concept. The authors find that the uneven regional development and stunted industrial growth which pushed these workers abroad are also responsible for the narrowly limited employment options which they face once they repatriate. For the urban repatriate, the market is limited to unemployment, the urban informal sector and scattered jobs, while for the rural repatriate, small-scale agriculture, multiple job holdings and unemployment are the only viable options.
Understanding congested travel in urban areas
Çolak, Serdar; Lima, Antonio; González, Marta C.
2016-01-01
Rapid urbanization and increasing demand for transportation burdens urban road infrastructures. The interplay of number of vehicles and available road capacity on their routes determines the level of congestion. Although approaches to modify demand and capacity exist, the possible limits of congestion alleviation by only modifying route choices have not been systematically studied. Here we couple the road networks of five diverse cities with the travel demand profiles in the morning peak hour obtained from billions of mobile phone traces to comprehensively analyse urban traffic. We present that a dimensionless ratio of the road supply to the travel demand explains the percentage of time lost in congestion. Finally, we examine congestion relief under a centralized routing scheme with varying levels of awareness of social good and quantify the benefits to show that moderate levels are enough to achieve significant collective travel time savings. PMID:26978719
Understanding congested travel in urban areas
NASA Astrophysics Data System (ADS)
Çolak, Serdar; Lima, Antonio; González, Marta C.
2016-03-01
Rapid urbanization and increasing demand for transportation burdens urban road infrastructures. The interplay of number of vehicles and available road capacity on their routes determines the level of congestion. Although approaches to modify demand and capacity exist, the possible limits of congestion alleviation by only modifying route choices have not been systematically studied. Here we couple the road networks of five diverse cities with the travel demand profiles in the morning peak hour obtained from billions of mobile phone traces to comprehensively analyse urban traffic. We present that a dimensionless ratio of the road supply to the travel demand explains the percentage of time lost in congestion. Finally, we examine congestion relief under a centralized routing scheme with varying levels of awareness of social good and quantify the benefits to show that moderate levels are enough to achieve significant collective travel time savings.
There is increasing demand to describe and account for the benefits that humans derive from ecosystem functions in decision-making. Comprehensive descriptions of these benefits, referred to as ecosystem services (ES), and their production can be limited because there is limited ...
USDA-ARS?s Scientific Manuscript database
Irrigation water availability is decreasing due to declining water sources and greater competition. Many producers must now comply with annual pumping restrictions that may limit overall productivity of crops like corn (Zea mays L.). Cotton [Gossypium hirsutum (L.)] water demand is less than corn, b...
12 CFR 217.101 - Premiums on deposits.
Code of Federal Regulations, 2010 CFR
2010-01-01
... exceed the applicable $10/$20 limitations and that no portion of the total cost of any premium has been... and the duration of the account balance shall not be considered the payment of interest on a demand deposit account and shall not be subject to the limitations in paragraph (a) of this section. [52 FR 47698...
Interactions between nutrition and gastrointestinal parasitism in sheep.
Sykes, A R; Coop, R L
2001-12-01
Effects of gastrointestinal nematode infection on metabolism and nutrient utilisation in sheep are reviewed. Infection induces protein deficiency by increasing the demand for amino acids in the alimentary tract while reducing supply through depression of appetite. Mechanisms through which improved protein nutrition could improve the performance of the host are then discussed. Opportunities for capitalising on such effects are limited by our rudimentary understanding of the cell-mediated immune response in gastrointestinal epithelial tissue. Both resistance of the animal to larval establishment and performance in the face of larval challenge can be enhanced by improved protein nutrition. However, enhanced immune responses may not necessarily be synonymous with improved productivity except at luxurious levels of protein intake, because of apparently competing demands for protein. Such levels of protein nutrition are difficult to achieve in pasture-based systems, because of the protein limiting role of the rumen. Work with proteinprotecting tannins to overcome this limitation is discussed. The much more limited evidence for effect of mineral nutrition, particularly copper (Cu), molybdenum (Mo), cobalt (Co) and phosphorus (P), on outcome of larval challenge is also reviewed.
Mechanisms of physical activity limitation in chronic lung diseases.
Vogiatzis, Ioannis; Zakynthinos, George; Andrianopoulos, Vasileios
2012-01-01
In chronic lung diseases physical activity limitation is multifactorial involving respiratory, hemodynamic, and peripheral muscle abnormalities. The mechanisms of limitation discussed in this paper relate to (i) the imbalance between ventilatory capacity and demand, (ii) the imbalance between energy demand and supply to working respiratory and peripheral muscles, and (iii) the factors that induce peripheral muscle dysfunction. In practice, intolerable exertional symptoms (i.e., dyspnea) and/or leg discomfort are the main symptoms that limit physical performance in patients with chronic lung diseases. Furthermore, the reduced capacity for physical work and the adoption of a sedentary lifestyle, in an attempt to avoid breathlessness upon physical exertion, cause profound muscle deconditioning which in turn leads to disability and loss of functional independence. Accordingly, physical inactivity is an important component of worsening the patients' quality of life and contributes importantly to poor prognosis. Identifying the factors which prevent a patient with lung disease to easily carry out activities of daily living provides a unique as well as important perspective for the choice of the appropriate therapeutic strategy.
Material challenges for transducer designers in the 21st century
NASA Astrophysics Data System (ADS)
Lindberg, Jan F.
2002-07-01
The modern U.S. Navy is rapidly evolving to meet the challenges of operating in the littorals. This focus changes the rules, especially to the designers of sonar systems that now need to aggressively engage quiet diesel electric submarine threats and neutralize sophisticated underwater mines. These new responsibilities dictate that new concepts be developed. To meet these new demands on the sonar system, transducer designers are being tasked to design transducers and to utilize new materials to address performance requirements that were never even imagined a decade ago. Sensor needs are no longer limited to pressure types but now have to sense velocity or acceleration. Sources are challenged to both frequency extent and power levels. The need to physically move sources off of submarines and surface combatants and onto vehicles with limited energy capabilities prompt the challenge of efficient bandwidth and high coupling. These are the needs of the 'next Navy'; the needs of the 'Navy after next' will present an even more demanding scenario. The future will demand revolutionary technology at the micro level with devices utilizing new power sources and new materials.
Evaluating the impacts of real-time pricing on the usage of wind generation
Sioshansi, Ramteen; Short, Walter
2009-02-13
One of the impediments to large-scale use of wind generation within power systems is its nondispatchability and variable and uncertain real-time availability. Operating constraints on conventional generators such as minimum generation points, forbidden zones, and ramping limits as well as system constraints such as power flow limits and ancillary service requirements may force a system operator to curtail wind generation in order to ensure feasibility. Furthermore, the pattern of wind availability and electricity demand may not allow wind generation to be fully utilized in all hours. One solution to these issues, which could reduce these inflexibilities, is the use ofmore » real-time pricing (RTP) tariffs which can both smooth-out the diurnal load pattern in order to reduce the impact of binding unit operating and system constraints on wind utilization, and allow demand to increase in response to the availability of costless wind generation. As a result, we use and analyze a detailed unit commitment model of the Texas power system with different estimates of demand elasticities to demonstrate the potential increases in wind generation from implementing RTP.« less
Kimberly A. Novick; Chelcy F. Miniat; James M. Vose
2016-01-01
We merge concepts from stomatal optimization theory and cohesionâtension theory to examine the dynamics of three mechanisms that are potentially limiting to leaf-level gas exchange in trees during drought: (1) a âdemand limitationâ driven by an assumption of optimal stomatal functioning; (2) âhydraulic limitationâ of water movement from the roots to the leaves...
Modeling water demand when households have multiple sources of water
NASA Astrophysics Data System (ADS)
Coulibaly, Lassina; Jakus, Paul M.; Keith, John E.
2014-07-01
A significant portion of the world's population lives in areas where public water delivery systems are unreliable and/or deliver poor quality water. In response, people have developed important alternatives to publicly supplied water. To date, most water demand research has been based on single-equation models for a single source of water, with very few studies that have examined water demand from two sources of water (where all nonpublic system water sources have been aggregated into a single demand). This modeling approach leads to two outcomes. First, the demand models do not capture the full range of alternatives, so the true economic relationship among the alternatives is obscured. Second, and more seriously, economic theory predicts that demand for a good becomes more price-elastic as the number of close substitutes increases. If researchers artificially limit the number of alternatives studied to something less than the true number, the price elasticity estimate may be biased downward. This paper examines water demand in a region with near universal access to piped water, but where system reliability and quality is such that many alternative sources of water exist. In extending the demand analysis to four sources of water, we are able to (i) demonstrate why households choose the water sources they do, (ii) provide a richer description of the demand relationships among sources, and (iii) calculate own-price elasticity estimates that are more elastic than those generally found in the literature.
NASA Astrophysics Data System (ADS)
Ibarrola-Rivas, M. J.; Granados-Ramírez, R.; Nonhebel, S.
2017-12-01
Land and water are essential local resources for food production but are limited. The main drivers of increasing food demand are population growth and dietary changes, which depend on the socioeconomic situation of the population. These two factors affect the availability of local resources: population growth reduces the land and water per person; and adoption of affluent diets increases the demand for land and water per person. This study shows potentials of global food supply by linking food demand drivers with national land and water availability. Whether the available land and water is enough to meet national food demand was calculated for 187 countries. The calculations were performed for the past situation (1960 and 2010) and to assess four future scenarios (2050) to discuss different paths of diets, population numbers and agricultural expansion. Inclusion of the demand perspective in the analysis has shown stronger challenges for future global food supply than have other studies. The results show that with the "business as usual" scenario, 40% of the global population in 2050 will live in countries with not enough land nor water to meet the demands of their population. Restriction to basic diets will be the most effective in lowering both land and water constraints. Our results identify both food production and food demand factors, and the regions that may experience the strongest challenges in 2050.
Area under the curve as a novel metric of behavioral economic demand for alcohol.
Amlung, Michael; Yurasek, Ali; McCarty, Kayleigh N; MacKillop, James; Murphy, James G
2015-06-01
Behavioral economic purchase tasks can be readily used to assess demand for a number of addictive substances, including alcohol, tobacco, and illicit drugs. However, several methodological limitations associated with the techniques used to quantify demand may reduce the utility of demand measures. In the present study, we sought to introduce area under the curve (AUC), commonly used to quantify degree of delay discounting, as a novel index of demand. A sample of 207 heavy-drinking college students completed a standard alcohol purchase task and provided information about typical weekly drinking patterns and alcohol-related problems. Level of alcohol demand was quantified using AUC--which reflects the entire amount of consumption across all drink prices--as well as the standard demand indices (e.g., intensity, breakpoint, Omax, Pmax, and elasticity). Results indicated that AUC was significantly correlated with each of the other demand indices (rs = .42-.92), with particularly strong associations with Omax (r = .92). In regression models, AUC and intensity were significant predictors of weekly drinking quantity, and AUC uniquely predicted alcohol-related problems, even after controlling for drinking level. In a parallel set of analyses, Omax also predicted drinking quantity and alcohol problems, although Omax was not a unique predictor of the latter. These results offer initial support for using AUC as an index of alcohol demand. Additional research is necessary to further validate this approach and to examine its utility in quantifying demand for other addictive substances such as tobacco and illicit drugs. (c) 2015 APA, all rights reserved).
Service Demand Discovery Mechanism for Mobile Social Networks.
Wu, Dapeng; Yan, Junjie; Wang, Honggang; Wang, Ruyan
2016-11-23
In the last few years, the service demand for wireless data over mobile networks has continually been soaring at a rapid pace. Thereinto, in Mobile Social Networks (MSNs), users can discover adjacent users for establishing temporary local connection and thus sharing already downloaded contents with each other to offload the service demand. Due to the partitioned topology, intermittent connection and social feature in such a network, the service demand discovery is challenging. In particular, the service demand discovery is exploited to identify the best relay user through the service registration, service selection and service activation. In order to maximize the utilization of limited network resources, a hybrid service demand discovery architecture, such as a Virtual Dictionary User (VDU) is proposed in this paper. Based on the historical data of movement, users can discover their relationships with others. Subsequently, according to the users activity, VDU is selected to facilitate the service registration procedure. Further, the service information outside of a home community can be obtained through the Global Active User (GAU) to support the service selection. To provide the Quality of Service (QoS), the Service Providing User (SPU) is chosen among multiple candidates. Numerical results show that, when compared with other classical service algorithms, the proposed scheme can improve the successful service demand discovery ratio by 25% under reduced overheads.
van Doorn, Yvonne; van Ruysseveldt, Joris; van Dam, Karen; Mistiaen, Wilhelm; Nikolova, Irina
2016-10-01
This study investigated whether Nigerian nurses' emotional exhaustion and active learning were predicted by job demands, control and social support. Limited research has been conducted concerning nurses' work stress in developing countries, such as Nigeria. Accordingly, it is not clear whether work interventions for improving nurses' well-being in these countries can be based on work stress models that are developed in Western countries, such as the job demand control support model, as well as on empirical findings of job demand control support research. Nurses from Nurses Across the Borders Nigeria were invited to complete an online questionnaire containing validated scales; 210 questionnaires were fully completed and analysed. Multiple regression analysis was used to test the hypotheses. Emotional exhaustion was higher for nurses who experienced high demands and low supervisor support. Active learning occurred when nurses worked under conditions of high control and high supervisor support. The findings suggest that the job demand control support model is applicable in a Nigerian nursing situation; the model indicates which occupational stressors contribute to poor well-being in Nigerian nurses and which work characteristics may boost nurses' active learning. Job (re)design interventions can enhance nurses' well-being and learning by guarding nurses' job demands, and stimulating job control and supervisor support. © 2016 John Wiley & Sons Ltd.
Tan, Lavinia; Hackenberg, Timothy D
2015-11-01
Pigeons' demand and preference for specific and generalized tokens was examined in a token economy. Pigeons could produce and exchange different colored tokens for food, for water, or for food or water. Token production was measured across three phases, which examined: (1) across-session price increases (typical demand curve method); (2) within-session price increases (progressive-ratio, PR, schedule); and (3) concurrent pairwise choices between the token types. Exponential demand curves were fitted to the response data and accounted for over 90% total variance. Demand curve parameter values, Pmax , Omax and α showed that demand was ordered in the following way: food tokens, generalized tokens, water tokens, both in Phase 1 and in Phase 3. This suggests that the preferences were predictable on the basis of elasticity and response output from the demand analysis. Pmax and Omax values failed to consistently predict breakpoints and peak response rates in the PR schedules in Phase 2, however, suggesting limits on a unitary conception of reinforcer efficacy. The patterns of generalized token production and exchange in Phase 3 suggest that the generalized tokens served as substitutes for the specific food and water tokens. Taken together, the present findings demonstrate the utility of behavioral economic concepts in the analysis of generalized reinforcement. © Society for the Experimental Analysis of Behavior.
Two-and-a-half-year-olds succeed at a traditional false-belief task with reduced processing demands
Scott, Rose M.; Baillargeon, Renée
2016-01-01
When tested with traditional false-belief tasks, which require answering a standard question about the likely behavior of an agent with a false belief, children perform below chance until age 4 y or later. When tested without such questions, however, children give evidence of false-belief understanding much earlier. Are traditional tasks difficult because they tap a more advanced form of false-belief understanding (fundamental-change view) or because they impose greater processing demands (processing-demands view)? Evidence that young children succeed at traditional false-belief tasks when processing demands are reduced would support the latter view. In prior research, reductions in inhibitory-control demands led to improvements in young children’s performance, but often only to chance (instead of below-chance) levels. Here we examined whether further reductions in processing demands might lead to success. We speculated that: (i) young children could respond randomly in a traditional low-inhibition task because their limited information-processing resources are overwhelmed by the total concurrent processing demands in the task; and (ii) these demands include those from the response-generation process activated by the standard question. This analysis suggested that 2.5-y-old toddlers might succeed at a traditional low-inhibition task if response-generation demands were also reduced via practice trials. As predicted, toddlers performed above chance following two response-generation practice trials; toddlers failed when these trials either were rendered less effective or were used in a high-inhibition task. These results support the processing-demands view: Even toddlers succeed at a traditional false-belief task when overall processing demands are reduced. PMID:27821728
ERIC Educational Resources Information Center
Ekeland, Anders; Tomlinson, Mark
This document reports a study of the possibility of making indicators of demand and supply of high skilled labor based on the Labor Force Survey (LFS), a data source available in all European countries. Part 1 is a summary of a pilot study of three countries: United Kingdom (UK), Netherlands, and Norway. It concludes LFS is a limited data source…
New product forecasting with limited or no data
NASA Astrophysics Data System (ADS)
Ismai, Zuhaimy; Abu, Noratikah; Sufahani, Suliadi
2016-10-01
In the real world, forecasts would always be based on historical data with the assumption that the behaviour be the same for the future. But how do we forecast when there is no such data available? New product or new technologies normally has limited amount of data available. Knowing that forecasting is valuable for decision making, this paper presents forecasting of new product or new technologies using aggregate diffusion models and modified Bass Model. A newly launched Proton car and its penetration was chosen to demonstrate the possibility of forecasting sales demand where there is limited or no data available. The model was developed to forecast diffusion of new vehicle or an innovation in the Malaysian society. It is to represent the level of spread on the new vehicle among a given set of the society in terms of a simple mathematical function that elapsed since the introduction of the new product. This model will forecast the car sales volume. A procedure of the proposed diffusion model was designed and the parameters were estimated. Results obtained by applying the proposed diffusion model and numerical calculation shows that the model is robust and effective for forecasting demand of the new vehicle. The results reveal that newly developed modified Bass diffusion of demand function has significantly contributed for forecasting the diffusion of new Proton car or new product.
Modeling and Economic Analysis of Power Grid Operations in a Water Constrained System
NASA Astrophysics Data System (ADS)
Zhou, Z.; Xia, Y.; Veselka, T.; Yan, E.; Betrie, G.; Qiu, F.
2016-12-01
The power sector is the largest water user in the United States. Depending on the cooling technology employed at a facility, steam-electric power stations withdrawal and consume large amounts of water for each megawatt hour of electricity generated. The amounts are dependent on many factors, including ambient air and water temperatures, cooling technology, etc. Water demands from most economic sectors are typically highest during summertime. For most systems, this coincides with peak electricity demand and consequently a high demand for thermal power plant cooling water. Supplies however are sometimes limited due to seasonal precipitation fluctuations including sporadic droughts that lead to water scarcity. When this occurs there is an impact on both unit commitments and the real-time dispatch. In this work, we model the cooling efficiency of several different types of thermal power generation technologies as a function of power output level and daily temperature profiles. Unit specific relationships are then integrated in a power grid operational model that minimizes total grid production cost while reliably meeting hourly loads. Grid operation is subject to power plant physical constraints, transmission limitations, water availability and environmental constraints such as power plant water exit temperature limits. The model is applied to a standard IEEE-118 bus system under various water availability scenarios. Results show that water availability has a significant impact on power grid economics.
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.
Morris, Peter; Buys, Laurie; Vine, Desley
2014-01-01
An electricity demand reduction project based on comprehensive residential consumer engagement was established within an Australian community in 2008. By 2011, both the peak demand and grid supplied electricity consumption had decreased to below pre-intervention levels. This case study research explored the relationship developed between the utility, community and individual consumer from the residential customer perspective through qualitative research of 22 residential households. It is proposed that an energy utility can be highly successful at peak demand reduction by becoming a community member and a peer to residential consumers and developing the necessary trust, access, influence and partnership required to create the responsive environment to change. A peer-community approach could provide policymakers with a pathway for implementing pro-environmental behaviour for low carbon communities, as well as peak demand reduction, thereby addressing government emission targets while limiting the cost of living increases from infrastructure expenditure. PMID:24979234
Photosynthetic capacity regulation is uncoupled from nutrient limitation
NASA Astrophysics Data System (ADS)
Smith, N. G.; Keenan, T. F.; Prentice, I. C.; Wang, H.
2017-12-01
Ecosystem and Earth system models need information on leaf-level photosynthetic capacity, but to date typically rely on empirical estimates and an assumed dependence on nitrogen supply. Recent evidence suggests that leaf nitrogen is actively controlled though plant responses to photosynthetic demand. Here, we propose and test a theory of demand-driven coordination of photosynthetic processes, and use it to assess the relative roles of nutrient supply and photosynthetic demand. The theory captured 63% of observed variability in a global dataset of Rubisco carboxylation capacity (Vcmax; 3,939 values at 219 sites), suggesting that environmentally regulated biophysical costs and light availability are the first-order drivers of photosynthetic capacity. Leaf nitrogen, on the other hand, was a weak secondary driver of Vcmax, explaining less than 6% of additional observed variability. We conclude that leaf nutrient allocation is primarily driven by demand. Our theory offers a simple, robust strategy for dynamically predicting leaf-level photosynthetic capacity in global models.
Anderson, Rachel J; Dewhurst, Stephen A; Nash, Robert A
2012-03-01
Recent literature has argued that whereas remembering the past and imagining the future make use of shared cognitive substrates, simulating future events places heavier demands on executive resources. These propositions were explored in 3 experiments comparing the impact of imagery and concurrent task demands on speed and accuracy of past event retrieval and future event simulation. Results provide support for the suggestion that both past and future episodes can be constructed through 2 mechanisms: a noneffortful "direct" pathway and a controlled, effortful "generative" pathway. However, limited evidence emerged for the suggestion that simulating of future, compared with retrieving past, episodes places heavier demands on executive resources; only under certain conditions did it emerge as a more error prone and lengthier process. The findings are discussed in terms of how retrieval and simulation make use of the same cognitive substrates in subtly different ways. 2012 APA, all rights reserved
Morris, Peter; Buys, Laurie; Vine, Desley
2014-01-01
An electricity demand reduction project based on comprehensive residential consumer engagement was established within an Australian community in 2008. By 2011, both the peak demand and grid supplied electricity consumption had decreased to below pre-intervention levels. This case study research explored the relationship developed between the utility, community and individual consumer from the residential customer perspective through qualitative research of 22 residential households. It is proposed that an energy utility can be highly successful at peak demand reduction by becoming a community member and a peer to residential consumers and developing the necessary trust, access, influence and partnership required to create the responsive environment to change. A peer-community approach could provide policymakers with a pathway for implementing pro-environmental behaviour for low carbon communities, as well as peak demand reduction, thereby addressing government emission targets while limiting the cost of living increases from infrastructure expenditure.
Huang, Yu-Hwa; Du, Pey-Ian; Chen, Chin-Hui; Yang, Chin-Ann; Huang, Ing-Chung
2011-04-01
This study attempted to investigate the role of emotional exhaustion as a mediator on the relationship between job demands-control (JDC) model and mental health. Three-wave data from 297 employees were collected. The results showed that job demands were positively related to emotional exhaustion, and increasing job demands will increase the level of emotional exhaustion. Job control was negatively associated with emotional exhaustion; therefore, increasing job control will decrease the level of emotional exhaustion. Emotional exhaustion was negatively related to mental health. Emotional exhaustion fully mediated the relationship between job demands and mental health, and partially mediated the positive relationship between job control and mental health. In addition, job control was positively associated with mental health directly. The remarkable finding of the present study was that emotional exhaustion served as the key mediator between the JDC model and mental health. Theoretical and managerial implications and limitations were discussed.
NASA Astrophysics Data System (ADS)
Cao, Jin; Jiang, Zhibin; Wang, Kangzhou
2017-07-01
Many nonlinear customer satisfaction-related factors significantly influence the future customer demand for service-oriented manufacturing (SOM). To address this issue and enhance the prediction accuracy, this article develops a novel customer demand prediction approach for SOM. The approach combines the phase space reconstruction (PSR) technique with the optimized least square support vector machine (LSSVM). First, the prediction sample space is reconstructed by the PSR to enrich the time-series dynamics of the limited data sample. Then, the generalization and learning ability of the LSSVM are improved by the hybrid polynomial and radial basis function kernel. Finally, the key parameters of the LSSVM are optimized by the particle swarm optimization algorithm. In a real case study, the customer demand prediction of an air conditioner compressor is implemented. Furthermore, the effectiveness and validity of the proposed approach are demonstrated by comparison with other classical predication approaches.
Future land-use related water demand in California
Wilson, Tamara; Sleeter, Benjamin M.; Cameron, D. Richard
2016-01-01
Water shortages in California are a growing concern amidst ongoing drought, earlier spring snowmelt, projected future climate warming, and currently mandated water use restrictions. Increases in population and land use in coming decades will place additional pressure on already limited available water supplies. We used a state-and-transition simulation model to project future changes in developed (municipal and industrial) and agricultural land use to estimate associated water use demand from 2012 to 2062. Under current efficiency rates, total water use was projected to increase 1.8 billion cubic meters(+4.1%) driven primarily by urbanization and shifts to more water intensive crops. Only if currently mandated 25% reductions in municipal water use are continuously implemented would water demand in 2062 balance to water use levels in 2012. This is the first modeling effort of its kind to examine regional land-use related water demand incorporating historical trends of both developed and agricultural land uses.
Tiered co-payments, pricing, and demand in reference price markets for pharmaceuticals.
Herr, Annika; Suppliet, Moritz
2017-12-01
Health insurance companies curb price-insensitive behavior and the moral hazard of insureds by means of cost-sharing, such as tiered co-payments or reference pricing in drug markets. This paper evaluates the effect of price limits - below which drugs are exempt from co-payments - on prices and on demand. First, using a difference-in-differences estimation strategy, we find that the new policy decreases prices by 5 percent for generics and increases prices by 4 percent for brand-name drugs in the German reference price market. Second, estimating a nested-logit demand model, we show that consumers appreciate co-payment exempt drugs and calculate lower price elasticities for brand-name drugs than for generics. This explains the different price responses of brand-name and generic drugs and shows that price-related co-payment tiers are an effective tool to steer demand to low-priced drugs. Copyright © 2017 Elsevier B.V. All rights reserved.
Sweis, Nadia J; Cherukupalli, Rajeev
2016-11-01
To estimate the price elasticity of cigarette demand for university students aged 18-24 years in Jordan. Questions from the Global Adult Tobacco Survey were adapted and administered to students from 10 public universities in Jordan in 2014. A two-part econometric model of cigarette demand was estimated. Nearly one-third of university students in Jordan smoke, purchasing 33.2 packs per month and paying 1.70 Jordanian dinars on average (US$2.40) for a pack of 20 cigarettes. The price elasticity of cigarette demand was estimated to be -1.15. Higher taxes may be particularly effective in reducing smoking among University students in Jordan. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.
Fish consumption and track to a fish feed formulation
NASA Astrophysics Data System (ADS)
Cai-Juan, Soong; Ramli, Razamin; Rahman, Rosshairy Abdul
2015-12-01
Strategically located in the equator, Malaysia is blessed with plenty of fish supply. The high demand in fish consumption has helped the development in the fishery industry and provided numerous jobs in the secondary sector, contributing significantly to the nation's income. A survey was conducted to understand the trend of current demands for fish for the purpose of designing a feed formulation, which is still limited in this area of study. Results showed that grouper fish in restaurants commanded a very high price compared to other species of fish. Tiger grouper gained the highest demand in most restaurants, while giant grouper had the highest price in restaurants. Due to the demand and challenges to culture this type of fish, a framework for fish feed formulation is proposed. The formulation framework when materialized could be an alternative to the use of trash fish as the feed for grouper.
NASA Astrophysics Data System (ADS)
Neverre, Noémie; Dumas, Patrice
2014-05-01
The aim is to be able to assess future domestic water demands in a region with heterogeneous levels of economic development. This work offers an original combination of a quantitative projection of demands (similar to WaterGAP methodology) and an estimation of the marginal benefit of water. This method is applicable to different levels of economic development and usable for large-scale hydroeconomic modelling. The global method consists in building demand functions taking into account the impact of both the price of water and the level of equipment, proxied by economic development, on domestic water demand. Our basis is a 3-blocks inverse demand function: the first block consists of essential water requirements for food and hygiene; the second block matches intermediate needs; and the last block corresponds to additional water consumption, such as outdoor uses, which are the least valued. The volume of the first block is fixed to match recommended basic water requirements from the literature, but we assume that the volume limits of blocks 2 and 3 depend on the level of household equipment and therefore evolve with the level of GDP per capita (structural change), with a saturation. For blocks 1 and 2 we determine the value of water from elasticity, price and quantity data from the literature, using the point-extension method. For block 3, we use a hypothetical zero-cost demand and maximal demand with actual water costs to linearly interpolate the inverse demand function. These functions are calibrated on the 24 countries part of the Mediterranean basin using data from SIMEDD, and are used for the projection and valuation of domestic water demands at the 2050 horizon. They enable to project total water demand, and also the respective shares of the different categories of demand (basic demand, intermediate demand and additional uses). These projections are performed under different combined scenarios of population, GDP and water costs.
TGFβ1-induced leucine limitation uncovered by differential ribosome codon reading.
Loayza-Puch, Fabricio; Rooijers, Koos; Zijlstra, Jelle; Moumbeini, Behzad; Zaal, Esther A; Oude Vrielink, Joachim F; Lopes, Rui; Ugalde, Alejandro P; Berkers, Celia R; Agami, Reuven
2017-04-01
Cancer cells modulate their metabolic networks to support cell proliferation and a higher demand of building blocks. These changes may restrict the availability of certain amino acids for protein synthesis, which can be utilized for cancer therapy. However, little is known about the amino acid demand changes occurring during aggressive and invasive stages of cancer. Recently, we developed diricore, an approach based on ribosome profiling that can uncover amino acid limitations. Here, we applied diricore to a cellular model in which epithelial breast cells respond rapidly to TGFβ1, a cytokine essential for cancer progression and metastasis, and uncovered shortage of leucine. Further analyses indicated that TGFβ1 treatment of human breast epithelial cells reduces the expression of SLC3A2, a subunit of the leucine transporter, which diminishes leucine uptake and inhibits cell proliferation. Thus, we identified a specific amino acid limitation associated with the TGFβ1 response, a vulnerability that might be associated with aggressiveness in cancer. © 2017 The Authors.
Evergreen coniferous forests of the pacific northwest.
Waring, R H; Franklin, J F
1979-06-29
The massive, evergreen coniferous forests in the Pacific Northwest are unique among temperate forest regions of the world. The region's forests escaped decimation during Pleistocene glaciation; they are now dominated by a few broadly distributed and well-adapted conifers that grow to large size and great age. Large trees with evergreen needle- or scale-like leaves have distinct advantages under the current climatic regime. Photosynthesis and nutrient uptake and storage are possible during the relatively warm, wet fall and winter months. High evaporative demand during the warm, dry summer reduces photosynthesis. Deciduous hardwoods are repeatedly at a disadvantage in competing with conifers in the regional climate. Their photosynthesis is predominantly limited to the growing season when evaporative demand is high and water is often limiting. Most nutrients needed are also less available at this time. The large size attained by conifers provides a buffer against environmental stress (especially for nutrients and moisture). The long duration between destructive fires and storms permits conifers to outgrow hardwoods with more limited stature and life spans.
The Opposites Task: Using General Rules to Test Cognitive Flexibility in Preschoolers
ERIC Educational Resources Information Center
Baker, Sara T.; Friedman, Ori; Leslie, Alan M.
2010-01-01
Executive functions play an important role in cognitive development, and during the preschool years especially, children's performance is limited in tasks that demand flexibility in their behavior. We asked whether preschoolers would exhibit limitations when they are required to apply a general rule in the context of novel stimuli on every trial…
Wayne A. Freimund; David N. Cole
2001-01-01
Recent increases in demand have revitalized interest and controversy surrounding use limits and the effect of visitor density on wilderness experiences. A workshop held in Missoula, Montana, in June of 2000 addressed the potential for social science to contribute to understanding and managing increasingly populated wilderness conditions. Scientists identified progress...
Job Strain in Physical Therapists
Campo, Marc A.; Weiser, Sherri; Koenig, Karen L.
2009-01-01
Background: Job stress has been associated with poor outcomes. In focus groups and small-sample surveys, physical therapists have reported high levels of job stress. Studies of job stress in physical therapy with larger samples are needed. Objective: The purposes of this study were: (1) to determine the levels of psychological job demands and job control reported by physical therapists in a national sample, (2) to compare those levels with national norms, and (3) to determine whether high demands, low control, or a combination of both (job strain) increases the risk for turnover or work-related pain. Design: This was a prospective cohort study with a 1-year follow-up period. Methods: Participants were randomly selected members of the American Physical Therapy Association (n=882). Exposure assessments included the Job Content Questionnaire (JCQ), a commonly used instrument for evaluation of the psychosocial work environment. Outcomes included job turnover and work-related musculoskeletal disorders. Results: Compared with national averages, the physical therapists reported moderate job demands and high levels of job control. About 16% of the therapists reported changing jobs during follow-up. Risk factors for turnover included high job demands, low job control, job strain, female sex, and younger age. More than one half of the therapists reported work-related pain. Risk factors for work-related pain included low job control and job strain. Limitations: The JCQ measures only limited dimensions of the psychosocial work environment. All data were self-reported and subject to associated bias. Conclusions: Physical therapists’ views of their work environments were positive, including moderate levels of demands and high levels of control. Those therapists with high levels of demands and low levels of control, however, were at increased risk for both turnover and work-related pain. Physical therapists should consider the psychosocial work environment, along with other factors, when choosing a job. PMID:19608632
Power Sources for Micro-Autonomous Vehicles- Challenges and Prospects
NASA Technical Reports Server (NTRS)
Narayan, S. R.; Kisor, A.; Valdez, T. I.; Manohara, H.
2009-01-01
Micro-autonomous vehicle systems are expected to have expanded role in military missions by providing full spectrum intelligence, surveillance and reconnaissance support on the battlefield, suppression of enemy defenses, and enabling co-operative (swarm-like) configurations. Of the numerous demanding requirements of autonomy, sensing, navigation, mobility, etc., meeting the requirement of mission duration or endurance is a very challenging one. This requirement is demanding because of the constraints of mass and volume that limit the quantity of energy that can be stored on-board. Energy is required for mobility, payload operation, information processing, and communication. Mobility requirements typically place an extraordinary demand on the specific energy (Wh/kg) and specific power (W/kg) of the power source; the actual distribution of the energy between mobility and other system functions could vary substantially with the mission type. The power requirements for continuous mobility can vary from 100-1000 W/kg depending on the terrain, ground speed and flight speed. Even with the power source accounting for 30% of the mass of the vehicle, the best of rechargeable batteries can provide only up to 1-2 hours of run-time for a continuous power demand at 100W/kg. In the case of micro-aerial vehicles with flight speed requirements in the range of 5-15 m s-1, the mission times rarely exceed 20 minutes [2]. Further, the power required during take-off and hover can be twice or thrice that needed for steady level flight, and thus the number and sequence of such events is also limited by the mass and size of the power source. For operations such as "perch and stare" or "silent watch" the power demand is often only a tenth of that required during continuous flight. Thus, variation in power demand during various phases of the mission importantly affects the power source selection.
Development of a demand assignment/TDMA system for international business satellite communications
NASA Astrophysics Data System (ADS)
Nohara, Mitsuo; Takeuchi, Yoshio; Takahata, Fumio; Hirata, Yasuo; Yamazaki, Yoshiharu
An experimental IBS (international business satellite) communications system based on a demand assignment and TDMA (time-division multiple-access) operation has been developed. The system utilizes a limited satellite resource efficiently and provides various kinds of ISDN services totally. A discussion is presented of the IBS network configurations suitable to international communications and describes the developed communications system from the viewpoint of the hardware and software implementation. The performance in terms of the transmission quality and call processing is also demonstrated.
Effects of low sink demand on leaf photosynthesis under potassium deficiency.
Pan, Yonghui; Lu, Zhifeng; Lu, Jianwei; Li, Xiaokun; Cong, Rihuan; Ren, Tao
2017-04-01
The interaction between low sink demand and potassium (K) deficiency in leaf photosynthesis was not intensively investigated, therefore this interaction was investigated in winter oilseed rape (Brassica napus L.). Plants subjected to sufficient (+K) or insufficient (-K) K supply treatments were maintained or removed their flowers and pods; these conditions were defined as high sink demand (HS) or low sink demand (LS), respectively. The low sink demand induced a lower photosynthetic rate (P n ), especially in the -K treatment during the first week. A negative relationship between P n and carbohydrate concentration was observed in the -K treatment but not in the +K treatment, suggesting that the decrease in P n in the -K treatment was the result of sink feedback regulation under low sink demand. Longer sink removal duration increased carbohydrate concentration, but the enhanced assimilate did not influence P n . On the contrary, low sink demand resulted in a high K concentration, slower chloroplast degradation rate and better PSII activity, inducing a higher P n compared with HS. Consequently, low sink demand decreased leaf photosynthesis over the short term due to sink feedback regulation, and potassium deficiency enhanced the photosynthetic decrease through carbohydrate accumulation and a lower carbohydrate concentration threshold for initiating photosynthesis depression. A longer duration of limited sink demand and sufficient potassium supply resulted in a higher photosynthesis rate because of delayed chloroplast degradation. This finding indicates that the nutritional status plays a role in leaf photosynthesis variations due to sink-source manipulation. Copyright © 2017 Elsevier Masson SAS. All rights reserved.
Zhao, Chang; Sander, Heather A
2015-01-01
Studies that assess the distribution of benefits provided by ecosystem services across urban areas are increasingly common. Nevertheless, current knowledge of both the supply and demand sides of ecosystem services remains limited, leaving a gap in our understanding of balance between ecosystem service supply and demand that restricts our ability to assess and manage these services. The present study seeks to fill this gap by developing and applying an integrated approach to quantifying the supply and demand of a key ecosystem service, carbon storage and sequestration, at the local level. This approach follows three basic steps: (1) quantifying and mapping service supply based upon Light Detection and Ranging (LiDAR) processing and allometric models, (2) quantifying and mapping demand for carbon sequestration using an indicator based on local anthropogenic CO2 emissions, and (3) mapping a supply-to-demand ratio. We illustrate this approach using a portion of the Twin Cities Metropolitan Area of Minnesota, USA. Our results indicate that 1735.69 million kg carbon are stored by urban trees in our study area. Annually, 33.43 million kg carbon are sequestered by trees, whereas 3087.60 million kg carbon are emitted by human sources. Thus, carbon sequestration service provided by urban trees in the study location play a minor role in combating climate change, offsetting approximately 1% of local anthropogenic carbon emissions per year, although avoided emissions via storage in trees are substantial. Our supply-to-demand ratio map provides insight into the balance between carbon sequestration supply in urban trees and demand for such sequestration at the local level, pinpointing critical locations where higher levels of supply and demand exist. Such a ratio map could help planners and policy makers to assess and manage the supply of and demand for carbon sequestration.
Nitrogen and phosphorus limitation over long-term ecosystem development in terrestrial ecosystems.
Menge, Duncan N L; Hedin, Lars O; Pacala, Stephen W
2012-01-01
Nutrient limitation to net primary production (NPP) displays a diversity of patterns as ecosystems develop over a range of timescales. For example, some ecosystems transition from N limitation on young soils to P limitation on geologically old soils, whereas others appear to remain N limited. Under what conditions should N limitation and P limitation prevail? When do transitions between N and P limitation occur? We analyzed transient dynamics of multiple timescales in an ecosystem model to investigate these questions. Post-disturbance dynamics in our model are controlled by a cascade of rates, from plant uptake (very fast) to litter turnover (fast) to plant mortality (intermediate) to plant-unavailable nutrient loss (slow) to weathering (very slow). Young ecosystems are N limited when symbiotic N fixation (SNF) is constrained and P weathering inputs are high relative to atmospheric N deposition and plant N:P demand, but P limited under opposite conditions. In the absence of SNF, N limitation is likely to worsen through succession (decades to centuries) because P is mineralized faster than N. Over long timescales (centuries and longer) this preferential P mineralization increases the N:P ratio of soil organic matter, leading to greater losses of plant-unavailable N versus P relative to plant N:P demand. These loss dynamics favor N limitation on older soils despite the rising organic matter N:P ratio. However, weathering depletion favors P limitation on older soils when continual P inputs (e.g., dust deposition) are low, so nutrient limitation at the terminal equilibrium depends on the balance of these input and loss effects. If NPP switches from N to P limitation over long time periods, the transition time depends most strongly on the P weathering rate. At all timescales SNF has the capacity to overcome N limitation, so nutrient limitation depends critically on limits to SNF.
Water Demand Management Strategies and Challenges in the Upper Colorado River Basin
NASA Astrophysics Data System (ADS)
Kuhn, R. E.
2016-12-01
Under the 1922 Colorado River Compact, the Upper Basin (Colorado, New Mexico, Utah, and Wyoming) has flow obligations at Lee Ferry to downstream states and Mexico. The Colorado River Storage Project Act (CRSPA) of 1956 led to the construction of four large storage reservoirs. These provide river regulation to allow the Upper Basin to meet its obligations. Lake Powell, the largest and most important, and Lake Mead are now operated in a coordinated manner under the 2007 Interim Guidelines. Studies show that at current demand levels and if the hydrologic conditions the Basin has experienced since the mid-1980s continue or get drier, reservoir operations, alone, may not provide the necessary water to meet the Upper Basin's obligations. Therefore, the Upper Basin states are now studying demand management strategies that will reduce consumptive uses when total system reservoir storage reaches critically low levels. Demand management has its own economic, political and technical challenges and limitations and will provide new opportunities for applied research. This presentation will discuss some of those strategies, their challenges, and the kinds of information that research could provide to inform demand management.
Fujishiro, Kaori; Landsbergis, Paul; Roux, Ana V. Diez; Stukovsky, Karen Hinckley; Shrager, Sandi; Baron, Sherry
2014-01-01
Immigrants have a different social context from those who stay in their home country or those who were born to the country that immigrants now live. Cultural theory of risk perception suggests that social context influences one’s interpretation of questionnaire items. We examined psychometric properties of job control and job demand scales with US- and foreign-born workers who preferred English, Spanish, or Chinese (n=3114, mean age=58.1). Across all groups, the job control scale had acceptable Cronbach’s alpha (0.78–0.83) and equivalent factor loadings (ΔCFI<0.01). Immigrants had low alpha (0.42–0.65) for the job demands scale regardless of language, education, or age of migration. Two job-demand items had different factor loadings across groups. Among immigrants, both scales had inconsistent associations with perceived job stress and self-rated health. For a better understanding of immigrants’ job stress, the concept of job demands should be expanded and immigrants’ expectations for job control explored. (149/150 limit) PMID:20582720
Agent-based modelling of consumer energy choices
NASA Astrophysics Data System (ADS)
Rai, Varun; Henry, Adam Douglas
2016-06-01
Strategies to mitigate global climate change should be grounded in a rigorous understanding of energy systems, particularly the factors that drive energy demand. Agent-based modelling (ABM) is a powerful tool for representing the complexities of energy demand, such as social interactions and spatial constraints. Unlike other approaches for modelling energy demand, ABM is not limited to studying perfectly rational agents or to abstracting micro details into system-level equations. Instead, ABM provides the ability to represent behaviours of energy consumers -- such as individual households -- using a range of theories, and to examine how the interaction of heterogeneous agents at the micro-level produces macro outcomes of importance to the global climate, such as the adoption of low-carbon behaviours and technologies over space and time. We provide an overview of ABM work in the area of consumer energy choices, with a focus on identifying specific ways in which ABM can improve understanding of both fundamental scientific and applied aspects of the demand side of energy to aid the design of better policies and programmes. Future research needs for improving the practice of ABM to better understand energy demand are also discussed.
NASA Astrophysics Data System (ADS)
Nazemi, A.; Wheater, H. S.
2015-01-01
Human activities have caused various changes to the Earth system, and hence the interconnections between human activities and the Earth system should be recognized and reflected in models that simulate Earth system processes. One key anthropogenic activity is water resource management, which determines the dynamics of human-water interactions in time and space and controls human livelihoods and economy, including energy and food production. There are immediate needs to include water resource management in Earth system models. First, the extent of human water requirements is increasing rapidly at the global scale and it is crucial to analyze the possible imbalance between water demands and supply under various scenarios of climate change and across various temporal and spatial scales. Second, recent observations show that human-water interactions, manifested through water resource management, can substantially alter the terrestrial water cycle, affect land-atmospheric feedbacks and may further interact with climate and contribute to sea-level change. Due to the importance of water resource management in determining the future of the global water and climate cycles, the World Climate Research Program's Global Energy and Water Exchanges project (WRCP-GEWEX) has recently identified gaps in describing human-water interactions as one of the grand challenges in Earth system modeling (GEWEX, 2012). Here, we divide water resource management into two interdependent elements, related firstly to water demand and secondly to water supply and allocation. In this paper, we survey the current literature on how various components of water demand have been included in large-scale models, in particular land surface and global hydrological models. Issues of water supply and allocation are addressed in a companion paper. The available algorithms to represent the dominant demands are classified based on the demand type, mode of simulation and underlying modeling assumptions. We discuss the pros and cons of available algorithms, address various sources of uncertainty and highlight limitations in current applications. We conclude that current capability of large-scale models to represent human water demands is rather limited, particularly with respect to future projections and coupled land-atmospheric simulations. To fill these gaps, the available models, algorithms and data for representing various water demands should be systematically tested, intercompared and improved. In particular, human water demands should be considered in conjunction with water supply and allocation, particularly in the face of water scarcity and unknown future climate.
[Translation into Brazilian Portuguese and validation of the Work Limitations Questionnaire].
de Soárez, Patrícia Coelho; Kowalski, Clarissa Campos Guaragna; Ferraz, Marcos Bosi; Ciconelli, Rozana Mesquita
2007-07-01
To translate into Brazilian Portuguese, cross-culturally adapt, and evaluate the psychometric properties, reliability, and validity of the Work Limitations Questionnaire (WLQ). This cross-sectional observational study was performed in 2005 and 2006 at the Hospital São Paulo/Escola Paulista de Medicina of the Federal University of São Paulo, Brazil. Data from 150 individuals who were employed at the time of the study were obtained using the WLQ, the SF-36 (a generic quality of life questionnaire), and the SRQ-20 (used to screen for mental disorders). The WLQ has 25 items, which are divided into four domains: time management, physical demands, mental-interpersonal demands, and output demands. The questionnaires were administered as interviews to individuals without a university education, and were self-administered to individuals with a university degree. Descriptive statistics were used to characterize the sample. The intraclass correlation coefficient and Cronbach's alpha were used to assess reliability (internal consistency, test-retest, interobserver, and intraobserver agreement). The Pearson's correlation coefficient was used to assess construct validity. The mean age of the subjects was 37.6 years (standard deviation, +/- 9.6 years), and 64.7% of the subjects were female. The mean number of years at the job held at the time of the interview was 8.6 (+/- 8.3 years); 60.7% of the subjects were satisfied with their job, and 94.0% had not missed work in the preceding two weeks. In comparison to completely healthy persons, the mean productivity loss reported by the study subjects was 4.2%. Interobserver agreement was significant and high (0.600 to 0.800) or very high (0.800 to 1.000) in all domains, except physical demands (r = 0.497, moderate agreement). Intraobserver agreement was not significant for the time management and physical demands domains. The correlations associated with intraobserver agreement were moderately significant (0.400 to 0.600). Internal consistency was very high (Cronbach's alpha = 0.800 to 1.000). There was a significant correlation between all the SF-36 questionnaire domains and the WLQ domains of time management, mental-interpersonal demands, and output demands as well as the WLQ index score. A positive correlation was also found between the WLQ domains of time management, mental-interpersonal demands, and output demands and a positive result (score >or= 7) on the SRQ-20. The Brazilian Portuguese version of the WLQ is a reliable and valid scale to assess the impact of health problems on the productivity of Brazilian workers.
Exploring ethical justification for self-demand amputation.
Tomasini, Floris
2006-01-01
Self-demand amputees are persons who need to have one or more healthy limbs or digits amputated to fit the way they see themselves. They want to rid themselves of a limb that they believe does not belong to their body-identity. The obsessive desire to have appendages surgically removed to fit an alternative body-image is medically and ethically controversial. My purpose in this paper is to provide a number of normative and professional ethical perspectives on whether or not it is possible to justify surgery for self-demand amputees. In doing so I proceed dialogically, moving between empirical context and normative theory, revealing the taken for granted normative assumptions (what I call the natural attitude--a technical term borrowed from phenomenology) that provide ethical limits to justifying the treatment of self-demand amputees. While I critically examine both Kantian responses against as well as Utilitarian responses for amputation on demand, I conclude that neither normative tradition can fully incorporate an understanding of what it is like to be a self-demand amputee. Since neither theory can justify the apparent non-rational desire of amputation on demand, ethical justification, I argue, falls short of the recognition that there may be a problem. To end, I introduce a meta-ethical idea, "the struggle for recognition," opening up the theoretical possibility of a hermeneutics of recognition before ethical justification that may be more sensitive to the problem of radical embodied difference exemplified by self-demand amputees.
Impacts of Demand-Side Resources on Electric Transmission Planning
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hadley, Stanton W.; Sanstad, Alan H.
2015-01-01
Will demand resources such as energy efficiency (EE), demand response (DR), and distributed generation (DG) have an impact on electricity transmission requirements? Five drivers for transmission expansion are discussed: interconnection, reliability, economics, replacement, and policy. With that background, we review the results of a set of transmission studies that were conducted between 2010 and 2013 by electricity regulators, industry representatives, and other stakeholders in the three physical interconnections within the United States. These broad-based studies were funded by the US Department of Energy and included scenarios of reduced load growth due to EE, DR, and DG. While the studies weremore » independent and used different modeling tools and interconnect-specific assumptions, all provided valuable results and insights. However, some caveats exist. Demand resources were evaluated in conjunction with other factors, and limitations on transmission additions between scenarios made understanding the role of demand resources difficult. One study, the western study, included analyses over both 10- and 20-year planning horizons; the 10-year analysis did not show near-term reductions in transmission, but the 20-year indicated fewer transmission additions, yielding a 36percent capital cost reduction. In the eastern study the reductions in demand largely led to reductions in local generation capacity and an increased opportunity for low-cost and renewable generation to export to other regions. The Texas study evaluated generation changes due to demand, and is in the process of examining demand resource impacts on transmission.« less
Modeling irrigation behavior in groundwater systems
NASA Astrophysics Data System (ADS)
Foster, Timothy; Brozović, Nicholas; Butler, Adrian P.
2014-08-01
Integrated hydro-economic models have been widely applied to water management problems in regions of intensive groundwater-fed irrigation. However, policy interpretations may be limited as most existing models do not explicitly consider two important aspects of observed irrigation decision making, namely the limits on instantaneous irrigation rates imposed by well yield and the intraseasonal structure of irrigation planning. We develop a new modeling approach for determining irrigation demand that is based on observed farmer behavior and captures the impacts on production and water use of both well yield and climate. Through a case study of irrigated corn production in the Texas High Plains region of the United States we predict optimal irrigation strategies under variable levels of groundwater supply, and assess the limits of existing models for predicting land and groundwater use decisions by farmers. Our results show that irrigation behavior exhibits complex nonlinear responses to changes in groundwater availability. Declining well yields induce large reductions in the optimal size of irrigated area and irrigation use as constraints on instantaneous application rates limit the ability to maintain sufficient soil moisture to avoid negative impacts on crop yield. We demonstrate that this important behavioral response to limited groundwater availability is not captured by existing modeling approaches, which therefore may be unreliable predictors of irrigation demand, agricultural profitability, and resilience to climate change and aquifer depletion.
Water stress as a trigger of demand change: exploring the implications for drought planning
NASA Astrophysics Data System (ADS)
Garcia, M. E.; Islam, S.; Portney, K. E.
2015-12-01
Drought in the Anthropocene is a function of both supply and demand. Despite its importance, demand is typically incorporated into planning models exogenously using a single scenario of demand change over time. Alternatively, demand is incorporated endogenously in hydro-economic models based on the assumption of rationality. However, actors are constrained by limited information and information processing capabilities, casting doubt on the rationality assumption. Though the risk of water shortage changes incrementally with demand growth and hydrologic change, significant shifts in management are punctuated and often linked to periods of stress. The observation of lasting decreases in per capita demands in a number of cities during periods of water stress prompts an alternate hypothesis: the occurrence of water stress increases the tendency of cities to promote and enforce efficient technologies and behaviors and the tendency of users to adopt them. We show the relevance of this hypothesis by building a model of a hypothetical surface water system to answer the following question: what is the impact of reservoir operation policy on the reliability of water supply for a growing city? The model links the rate of demand decreases to the past reliability to compare standard operating policy (SOP) with hedging policy (HP). Under SOP, demand is fulfilled unless available supply drops below demand; under HP, water releases are reduced in anticipation of a deficit to decrease the risk of a large shortfall. The model shows that reservoir storage acts both as a buffer for variability and as a delay triggering oscillations around a sustainable level of demand. HP reduces the threshold for action thereby decreasing the delay and the oscillation effect. As a result per capita demand decrease during periods of water stress are more frequent but less drastic and the additive effect of small adjustments decreases the tendency of the system to overshoot available supplies.
Are prices enough? The economics of material demand reduction
Aidt, Toke; Jia, Lili
2017-01-01
Recent policy proposals to achieve carbon targets have emphasized material demand reduction strategies aimed at achieving material efficiency. We provide a bridge between the way economists and engineers think about efficiency. We use the tools of economics to think about policies directed at material efficiency and to evaluate the role and rationale for such policies. The analysis highlights when prices (or taxes) can be used to induce changes in material use and when taxes may not work. We argue that the role of taxes is limited by concerns about their distributional consequences, by international trade and the lack of international agreement on carbon prices, and by investment failures. This article is part of the themed issue ‘Material demand reduction’. PMID:28461434
Are prices enough? The economics of material demand reduction
NASA Astrophysics Data System (ADS)
Aidt, Toke; Jia, Lili; Low, Hamish
2017-05-01
Recent policy proposals to achieve carbon targets have emphasized material demand reduction strategies aimed at achieving material efficiency. We provide a bridge between the way economists and engineers think about efficiency. We use the tools of economics to think about policies directed at material efficiency and to evaluate the role and rationale for such policies. The analysis highlights when prices (or taxes) can be used to induce changes in material use and when taxes may not work. We argue that the role of taxes is limited by concerns about their distributional consequences, by international trade and the lack of international agreement on carbon prices, and by investment failures. This article is part of the themed issue 'Material demand reduction'.
Macfarlane, Christopher P.; Hoysak, Drew J.; Liley, N. Robin; Gage, Matthew J.G.
2009-01-01
Although theory and widespread evidence show that the evolution of egg size is driven primarily by offspring and maternal fitness demands, an additional explanation invokes sperm limitation as a selective force that could also influence egg size optima. Levitan proposed that constraints from gamete encounter in external fertilization environments could select for enlargement of ova to increase the physical size of the fertilization target. We test this theory using in vitro fertilization experiments in an externally fertilizing fish. Sockeye salmon (Onchorhyncus nerka) females show considerable between-individual variation in ovum size, and we explored the consequences of this natural variation for the fertilization success of individual eggs under conditions of sperm limitation. By engineering consistent conditions where in vitro fertilization rate was always intermediate, we were able to compare the sizes of fertilized and unfertilized eggs across 20 fertilization replicates. After controlling for any changes in volume through incubation, results showed that successfully fertilized eggs were significantly larger than the eggs that failed to achieve fertilization. Under conditions without sperm limitation, fertility was unaffected by egg size. Our findings therefore support Levitan's theory, demonstrating empirically that some element of egg size variation could be selected by fertilization demands under sperm limitation. However, further research on sperm limitation in natural spawnings is required to assess the selective importance of these results. PMID:19364734
Macfarlane, Christopher P; Hoysak, Drew J; Liley, N Robin; Gage, Matthew J G
2009-07-07
Although theory and widespread evidence show that the evolution of egg size is driven primarily by offspring and maternal fitness demands, an additional explanation invokes sperm limitation as a selective force that could also influence egg size optima. Levitan proposed that constraints from gamete encounter in external fertilization environments could select for enlargement of ova to increase the physical size of the fertilization target. We test this theory using in vitro fertilization experiments in an externally fertilizing fish. Sockeye salmon (Onchorhyncus nerka) females show considerable between-individual variation in ovum size, and we explored the consequences of this natural variation for the fertilization success of individual eggs under conditions of sperm limitation. By engineering consistent conditions where in vitro fertilization rate was always intermediate, we were able to compare the sizes of fertilized and unfertilized eggs across 20 fertilization replicates. After controlling for any changes in volume through incubation, results showed that successfully fertilized eggs were significantly larger than the eggs that failed to achieve fertilization. Under conditions without sperm limitation, fertility was unaffected by egg size. Our findings therefore support Levitan's theory, demonstrating empirically that some element of egg size variation could be selected by fertilization demands under sperm limitation. However, further research on sperm limitation in natural spawnings is required to assess the selective importance of these results.
NASA Astrophysics Data System (ADS)
Marteau, Theresa M.
2017-05-01
Meeting climate change targets to limit global warming to 2°C requires rapid and large reductions in demand for products that most contribute to greenhouse gas (GHG) emissions. These include production of bulk materials (e.g. steel and cement), energy supply (e.g. fossil fuels) and animal source foods (particularly ruminants and their products). Effective strategies to meet these targets require transformative changes in supply as well as demand, involving changes in economic, political and legal systems at local, national and international levels, building on evidence from many disciplines. This paper outlines contributions from behavioural science in reducing demand. Grounded in dual-process models of human behaviour (involving non-conscious and conscious processes) this paper considers first why interventions aimed at changing population values towards the environment are usually insufficient or unnecessary for reducing demand although they may be important in increasing public acceptability of policies that could reduce demand. It then outlines two sets of evidence from behavioural science towards effective systems-based strategies, to identify interventions likely to be effective at: (i) reducing demand for products that contribute most to GHG emissions, mainly targeting non-conscious processes and (ii) increasing public acceptability for policy changes to enable these interventions, targeting conscious processes. This article is part of the themed issue 'Material demand reduction'.
Marteau, Theresa M
2017-06-13
Meeting climate change targets to limit global warming to 2°C requires rapid and large reductions in demand for products that most contribute to greenhouse gas (GHG) emissions. These include production of bulk materials (e.g. steel and cement), energy supply (e.g. fossil fuels) and animal source foods (particularly ruminants and their products). Effective strategies to meet these targets require transformative changes in supply as well as demand, involving changes in economic, political and legal systems at local, national and international levels, building on evidence from many disciplines. This paper outlines contributions from behavioural science in reducing demand. Grounded in dual-process models of human behaviour (involving non-conscious and conscious processes) this paper considers first why interventions aimed at changing population values towards the environment are usually insufficient or unnecessary for reducing demand although they may be important in increasing public acceptability of policies that could reduce demand. It then outlines two sets of evidence from behavioural science towards effective systems-based strategies, to identify interventions likely to be effective at: (i) reducing demand for products that contribute most to GHG emissions, mainly targeting non-conscious processes and (ii) increasing public acceptability for policy changes to enable these interventions, targeting conscious processes.This article is part of the themed issue 'Material demand reduction'. © 2017 The Authors.
2017-01-01
Meeting climate change targets to limit global warming to 2°C requires rapid and large reductions in demand for products that most contribute to greenhouse gas (GHG) emissions. These include production of bulk materials (e.g. steel and cement), energy supply (e.g. fossil fuels) and animal source foods (particularly ruminants and their products). Effective strategies to meet these targets require transformative changes in supply as well as demand, involving changes in economic, political and legal systems at local, national and international levels, building on evidence from many disciplines. This paper outlines contributions from behavioural science in reducing demand. Grounded in dual-process models of human behaviour (involving non-conscious and conscious processes) this paper considers first why interventions aimed at changing population values towards the environment are usually insufficient or unnecessary for reducing demand although they may be important in increasing public acceptability of policies that could reduce demand. It then outlines two sets of evidence from behavioural science towards effective systems-based strategies, to identify interventions likely to be effective at: (i) reducing demand for products that contribute most to GHG emissions, mainly targeting non-conscious processes and (ii) increasing public acceptability for policy changes to enable these interventions, targeting conscious processes. This article is part of the themed issue ‘Material demand reduction’. PMID:28461435
NASA Astrophysics Data System (ADS)
Elmore, A. J.; Nelson, D. M.; Craine, J. M.
2016-12-01
There is wide agreement that anthropogenic climate warming has influenced the phenology of forests during the late twentieth and early twenty-first centuries. A critical question for predicting the magnitude of future warming under different emissions scenarios is the degree to which forest productivity responds to longer growing seasons in the face of concurrent changes in other drivers of productivity. Longer growing seasons can lead to increased photosynthesis and productivity, which would represent a negative feedback to rising CO2 and consequently warming. Alternatively, increased demand for soil resources due to a longer photosynthetically active period in conjunction with other global change factors might exacerbate resource limitation, restricting forest productivity response to a longer growing season. In this case, increased spring-time productivity has the potential to increase plant N limitation by increasing plant demand for N more than N supplies, or increasing early-season ecosystem N losses. Long-term direct measurements are not yet available to specifically address this question, but advances in remote sensing and dendroecological methods present opportunities to acquire information retrospectively to advance understanding of how phenological changes and resource availability to trees have been affecting forest productivity. Here we show that for 222 trees representing three species in eastern North America over the past 30 years earlier spring phenology has caused declines in N availability to trees by increasing demand for N relative to supply. The observed decline in N availability is not associated with reduced wood production, suggesting that other environmental changes such as increased atmospheric CO2 and water availability have likely overwhelmed reduced N availability. Given current trajectories of environmental changes, N limitation will likely continue to increase for these forests, possibly further limiting C sequestration potential.
Attentional Demands Predict Short-Term Memory Load Response in Posterior Parietal Cortex
ERIC Educational Resources Information Center
Magen, Hagit; Emmanouil, Tatiana-Aloi; McMains, Stephanie A.; Kastner, Sabine; Treisman, Anne
2009-01-01
Limits to the capacity of visual short-term memory (VSTM) indicate a maximum storage of only 3 or 4 items. Recently, it has been suggested that activity in a specific part of the brain, the posterior parietal cortex (PPC), is correlated with behavioral estimates of VSTM capacity and might reflect a capacity-limited store. In three experiments that…
How to Fall in Love with Time-Limited Therapy: Lessons from Poetry and Music
ERIC Educational Resources Information Center
Alcée, Michael D.; Sager, Tara A.
2017-01-01
With rising student demand, time-limited therapy is becoming the rule rather than the exception at college counseling centers today. While many have viewed this shift as an unwelcome intrusion, this article will examine how to embrace and capitalize on this new, compressed form. Rather than seeing it as a constraint, it will be argued that it…
Systems and methods for controlling energy use during a demand limiting period
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.
ERIC Educational Resources Information Center
Calaf, Dolores C.
2017-01-01
English for Speakers of Other Languages (ESOL) classes are in great demand by immigrant adults in the Boston area. The problem investigated in this study was the limited funding to implement ESOL programs in Boston, which has resulted in waiting lists for many contracted community-based programs. The purpose of this qualitative multiple case study…
James Grogan; Jurandir Galvao
2006-01-01
Post-logging seedling regeneration density by big-leaf mahogany (Swietenia macrophylla), a nonpioneer light-demanding timber species, is generally reported to be low to nonexistent. To investigate factors limiting seedling density following logging within the study region, we quantified seed production rates, germinability, dispersal patterns, and seed fates on the...
Ergonomic intervention for employed persons with rheumatic conditions.
Allaire, Saralynn J; Backman, Catherine L; Alheresh, Rawan; Baker, Nancy A
2013-01-01
Prior articles in this series on employment and arthritis have documented the major impact arthritis and other rheumatic conditions have on employment. As expected, physically demanding job tasks, including hand use, are substantial risk factors for work limitation. Computer use has been increasing. People with arthritis may choose occupations involving extensive computer use to avoid occupations with other physical demands. But studies show many people with arthritis conditions have difficulty using computers.Ergonomic assessment and implementation helps relieve the physical and other demands of jobs. The Ergonomic Assessment Tool for Arthritis (EATA) is specifically for people with arthritis conditions. Since the EATA can be conducted off worksite, it is feasible to use with workers not wishing to disclose their condition to their employer. Available research supports the effectiveness of ergonomic intervention as a viable method to reduce work limitation for persons with arthritis. Some workers will need additional vocational intervention to remain employed long term. However, ergonomic intervention is a useful first step, as it promotes awareness of arthritis effects on work activities. Assisting workers with arthritis or other rheumatic conditions to use ergonomics to enhance their ability to work well should be an important aspect of managing these conditions.
Pinyopornpanish, Kanokporn; Jiraporncharoen, Wichuda; Thaikla, Kanittha; Yoonut, Kulyapa; Angkurawaranon, Chaisiri
2018-03-21
Evidence from other countries has suggested that many controlled drugs are also offered online, even though it is illegal to sell these drugs without a license. To evaluate the current contents related to the supply and demand of sedatives and analgesic drugs available online in Thailand, with a particular focus on Facebook. A team of reviewers manually searched for data by entering keywords related to analgesic drugs and sedatives. The contents of the website were screened for supply and demand-related information. A total of 5,352 websites were found publicly available. The number of websites and Facebook pages containing the information potentially related to the supply and demand of analgesic drugs and sedatives was limited. Nine websites sold sedatives, and six websites sold analgesics directly. Fourteen Facebook pages were found, including 7 sedative pages and 7 analgesic pages. Within one year, the three remaining active pages multiplied in the number of followers by three- to nine-fold. The most popular Facebook page had over 2,900 followers. Both the internet and social media contain sites and pages where sedatives and analgesics are illegally advertised. These websites are searchable through common search engines. Although the number of websites is limited, the number of followers on these Facebook pages does suggest a growing number of people who are interested in such pages. Our study emphasized the importance of monitoring and developing potential plans relative to the online marketing of prescription drugs in Thailand.
Mărcuş, Oana; Stanciu, Oana; MacLeod, Colin; Liebregts, Heather; Visu-Petra, Laura
2016-10-01
Cognitive-affective flexibility represents the ability to switch between alternative ways of processing emotional stimuli according to situational demands and individual goals. Although reduced flexibility has been implicated as a mechanism for the development of anxiety, there is very limited data on this relationship in children and adolescents. The aim of the current study was to investigate cognitive-affective flexibility in preadolescents (N = 112, 50 girls, 11-12 and 13-14 years old) and to examine if this ability is related to individual differences in trait anxiety. Their interplay was assessed using the modified version of the Flexible Item Selection Task (FIST; Jacques and Zelazo 2001) with non-emotional stimuli (geometrical shapes) and the Emotional FIST (EM-FIST) with emotional stimuli (emotional facial expressions). Performance on the EM-FIST indicated that across the whole age range, trials requiring greater cognitive flexibility were more demanding than nonflexible ones, as revealed by both response time and accuracy performance. Moreover, flexibility demands were higher for younger children than for older ones but only in terms of response speed. Individual differences in trait anxiety moderated the impact of flexibility only on the EM-FIST. Being flexible on the EM-FIST was more demanding for high trait anxious children than for their low trait anxious peers. Lastly, overall girls responded faster than boys, but only in the EM-FIST. These findings extend the presently limited literature concerning variability in cognitive-affective flexibility during this sensitive developmental window.
Integrated noxious weed management.
DOT National Transportation Integrated Search
2003-06-01
The 1942-45 introduction of phenoxy herbicides offered selective weed control with limited manpower and resources. Entrepreneurs identified the profit incentive and created a demand for an increasing number of specific weed control chemicals. As a re...
Yang, Shangyuan; Liang, Zhiwei; Yu, Huadong; Wang, Yunlong; Chen, Yingxu
2014-02-01
Micro-electrolysis was applied in the present study to investigate the effect of pH, iron-carbon mass ratio, contact time, and treatment batch on the removal efficiency of chemical oxygen demand (COD) within an aminosilicone emulsion. The results exhibited that the removal efficiency of COD decreased linearly with the batch increase, and this tendency was consistent under the various conditions. The adsorption of activated carbons contributes a large portion to the elimination of COD within the aminosilicone emulsion. The oxidation action of iron-carbon micro-electrolysis was proven and the aminosilicone emulsion's COD removal contribution was approximately 16%. Aminosilicone polymers were adsorbed on the surface of activated carbons and iron chips, which contributes to the decline of COD removal efficiency and limits the contribution of oxidation action.
[Dementia, end of life and euthanasia].
Bier, J C; Salmon, E; Ivanoiu, A
2014-09-01
Among legislative criteria granting the right to practice euthanasia or assisted suicide, there are systematically four major elements. Precisely, any request must be voluntary, persistent, to be well thought and well informed. Such euthanasia raises numerous difficult questions in case of dementia. It also justifies thinking about possibilities that can offer specific arrangements of anticipated demands in such peculiar cases. Empirical experiences show us that it applies with difficulties in practice. Finally, to avoid that a big majority of these demands would find themselves not applied in practice, it would certainly be necessary to add to it structural valuation of advance care planning, and assure its recognition and development. These should not be limited to a single pathological target but would address all of us to increase advance care planning initiation, which remains the most limiting factor of such any early but continuous procedure.
Kono, Yuko; Matsushima, Eisuke; Uji, Masayo
2014-02-01
The 25-item Work Limitations Questionnaire (WLQ-25) measures presenteeism but has not been sufficiently validated in a Japanese population. A total of 451 employees from four information technology companies in Tokyo completed the WLQ-25 and questionnaires of other variables on two occasions, 2 weeks apart. The WLQ-25 yielded a two-factor structure: Cognitive Demand and Physical Demand. These subscales showed good internal consistency, and both were associated with adverse working conditions, greater perceived job strain, lower skill use, poorer workplace social support, and less satisfactory psychological adjustment. Intraclass correlation coefficients of the two WLQ-25 subscales between time 1 and time 2 were 0.78 and 0.55, respectively. This study suggests acceptable psychometric properties of the WLQ-25 in Japan.
NASA Technical Reports Server (NTRS)
1975-01-01
Major developments are examined which have taken place to date in the analysis of the power and energy demands on the APU/Hydraulic/Actuator Subsystem for space shuttle during the entry-to-touchdown (not including rollout) flight regime. These developments are given in the form of two subroutines which were written for use with the Space Shuttle Functional Simulator. The first subroutine calculates the power and energy demand on each of the three hydraulic systems due to control surface (inboard/outboard elevons, rudder, speedbrake, and body flap) activity. The second subroutine incorporates the R. I. priority rate limiting logic which limits control surface deflection rates as a function of the number of failed hydraulic. Typical results of this analysis are included, and listings of the subroutines are presented in appendicies.
Impact of warmer weather on electricity sector emissions due to building energy use
NASA Astrophysics Data System (ADS)
Meier, Paul; Holloway, Tracey; Patz, Jonathan; Harkey, Monica; Ahl, Doug; Abel, David; Schuetter, Scott; Hackel, Scott
2017-06-01
Most US energy consumption occurs in buildings, with cooling demands anticipated to increase net building electricity use under warmer conditions. The electricity generation units that respond to this demand are major contributors to sulfur dioxide (SO2) and nitrogen oxides (NOx), both of which have direct impacts on public health, and contribute to the formation of secondary pollutants including ozone and fine particulate matter. This study quantifies temperature-driven changes in power plant emissions due to increased use of building air conditioning. We compare an ambient temperature baseline for the Eastern US to a model-calculated mid-century scenario with summer-average temperature increases ranging from 1 C to 5 C across the domain. We find a 7% increase in summer electricity demand and a 32% increase in non-coincident peak demand. Power sector modeling, assuming only limited changes to current generation resources, calculated a 16% increase in emissions of NOx and an 18% increase in emissions of SO2. There is a high level of regional variance in the response of building energy use to climate, and the response of emissions to associated demand. The East North Central census region exhibited the greatest sensitivity of energy demand and associated emissions to climate.
Reimer, Bryan; Mehler, Bruce; Reagan, Ian; Kidd, David; Dobres, Jonathan
2016-12-01
There is limited research on trade-offs in demand between manual and voice interfaces of embedded and portable technologies. Mehler et al. identified differences in driving performance, visual engagement and workload between two contrasting embedded vehicle system designs (Chevrolet MyLink and Volvo Sensus). The current study extends this work by comparing these embedded systems with a smartphone (Samsung Galaxy S4). None of the voice interfaces eliminated visual demand. Relative to placing calls manually, both embedded voice interfaces resulted in less eyes-off-road time than the smartphone. Errors were most frequent when calling contacts using the smartphone. The smartphone and MyLink allowed addresses to be entered using compound voice commands resulting in shorter eyes-off-road time compared with the menu-based Sensus but with many more errors. Driving performance and physiological measures indicated increased demand when performing secondary tasks relative to 'just driving', but were not significantly different between the smartphone and embedded systems. Practitioner Summary: The findings show that embedded system and portable device voice interfaces place fewer visual demands on the driver than manual interfaces, but they also underscore how differences in system designs can significantly affect not only the demands placed on drivers, but also the successful completion of tasks.
Demand management and test request rationalization.
Smellie, W S A
2012-07-01
Demand for laboratory testing is increasing disproportionately to medical activity, and the tests involved are becoming increasingly complex. When this phenomenon is seen in parallel with declining teaching of laboratory medicine in the medical curriculum, a need emerges to manage demand to avoid unnecessary expenditure and improve the use of laboratory services: 'the right test in the right patient at the right time.' Various methods have been tried to manage demand, with success depending on the medical context, type of health service and preintervention situation. Because many factors contribute to demand, and the different settings in which these exist, it is not realistic to meta-analyse the studies and we are limited to trying to identify trends in results in particular situations. The studies suggest that education combined with facilitating interventions, such as feedback, prompts and changes to laboratory request forms are the most successful. From the perspective of a whole health service, it is important that results are not exaggerated by assessing benefits in terms of total rather than marginal cost. It would be desirable, although difficult, to include the impact on downstream clinical activity caused or avoided by the interventions. Advances in information and web technology may make the elusive goal of achieving substantial demand control more achievable.
Czarnecki, John B.; Clark, Brian R.; Stanton, Gregory P.
2003-01-01
The Mississippi River Valley alluvial aquifer is a water-bearing assemblage of gravels and sands that underlies about 32,000 square miles of Missouri, Kentucky, Tennessee, Mississippi, Louisiana, and Arkansas. Because of the heavy demands placed on the aquifer, several large cones of depression have formed in the potentiometric surface, resulting in lower well yields and degraded water quality in some areas. A ground-water flow model of the alluvial aquifer was previously developed for an area covering 3,826 square miles, extending south from the Arkansas River into the southeastern corner of Arkansas, parts of northeastern Louisiana, and western Mississippi. The flow-model results indicated that continued ground-water withdrawals at rates commensurate with those of 1997 could not be sustained indefinitely without causing water levels to decline below half the original saturated thickness of the aquifer. Conjunctive-use optimization modeling was applied to the flow model of the alluvial aquifer to develop withdrawal rates that could be sustained relative to the constraints of critical ground-water area designation. These withdrawal rates form the basis for estimates of sustainable yield from the alluvial aquifer and from rivers specified within the alluvial aquifer model. A management problem was formulated as one of maximizing the sustainable yield from all ground-water and surface-water withdrawal cells within limits imposed by plausible withdrawal rates, and within specified constraints involving hydraulic head and streamflow. Steady-state conditions were selected because the maximized withdrawals are intended to represent sustainable yield of the system (a rate that can be maintained indefinitely).One point along the Arkansas River and one point along Bayou Bartholomew were specified for obtaining surface-water sustainable-yield estimates within the optimization model. Streamflow constraints were specified at two river cells based on average 7-day low flows with 10-year recurrence intervals. Sustainable-yield estimates were affected by the allowable upper limit on withdrawals from wells specified in the optimization model. Withdrawal rates were allowed to increase to 200 percent of the withdrawal rate in 1997. As the overall upper limit is increased, the sustainable yield generally increases. Tests with the optimization model show that without limits on pumping, wells adjacent to sources of water, such as large rivers, would have optimal withdrawal rates that were orders of magnitude larger than rates corresponding to those of 1997. Specifying an upper withdrawal limit of 100 percent of the 1997 withdrawal rate, the sustainable yield from ground water for the entire study area is 70.3 million cubic feet per day, which is about 96 percent of the amount withdrawn in 1997 (73.5 million cubic feet per day). If the upper withdrawal limit is increased to 150 percent of the 1997 withdrawal rate, the sustainable yield from ground water for the entire study area is 80.6 million cubic feet per day, which is about 110 percent of the amount withdrawn in 1997. If the upper withdrawal limit is increased to 200 percent of the 1997 withdrawal rate, the sustainable yield from ground water for the entire study area is 110.2 million cubic feet per day, which is about 150 percent of the amount withdrawn in 1997. Total sustainable yield from the Arkansas River and Bayou Bartholomew is about 4,900 million cubic feet per day, or about 6,700 percent of the amount of ground-water withdrawn in 1997. The large, sustainable yields from surface water represent a potential source of water that could supplement ground water and meet the total water demand. Unmet demand (defined as the difference between the optimized withdrawal rate or sustainable yield, and the anticipated demand) was calculated using different demand rates based on multiples of the 1997-withdrawal rate. Assuming that demand is the 1997 withdrawal rate, and that sustainable-
Ad libitum or demand/semi-demand feeding versus scheduled interval feeding for preterm infants.
McCormick, Felicia M; Tosh, Karen; McGuire, William
2010-02-17
Scheduled interval feeding of prescribed enteral volumes is current standard practice for preterm infants. However, feeding preterm infants in response to their hunger and satiation cues (ad libitum or demand/semi demand) rather than at scheduled intervals might help in the establishment of independent oral feeding, increase nutrient intake and growth rates, and allow earlier hospital discharge. To assess the effect of a policy of feeding preterm infants on an ad libitum or demand/semi-demand basis versus feeding prescribed volumes at scheduled intervals on growth rates and the time to hospital discharge. We used the standard search strategy of the Cochrane Neonatal Review Group. This included searches of the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, Issue 4, 2009), MEDLINE (1966 to Oct 2009), EMBASE (1980 to Oct 2009), CINAHL (1982 to Oct 2009), conference proceedings, and previous reviews. Randomised or quasi-randomised controlled trials (including cluster randomised trials) that compared a policy of feeding preterm infants on an ad libitum or demand/semi-demand basis versus feeding at scheduled intervals. We used the standard methods of the Cochrane Neonatal Review Group with separate evaluation of trial quality and data extraction by two review authors. We found eight randomised controlled trials that compared ad libitum or demand/semi-demand regimens with scheduled interval regimes in preterm infants in the transition phase from intragastric tube to oral feeding. The trials were generally small and of variable methodological quality. The duration of the intervention and the duration of data collection and follow-up in most of the trials was not likely to have allowed detection of measurable effects on growth. Three trials reported that feeding preterm infants using an ad libitum or demand/semi-demand feeding regimen allowed earlier discharge from hospital (by about two to four days) but other trials did not confirm this finding. Limited evidence exists that feeding preterm infants with ad libitum or demand/semi-demand regimens allows earlier attainment of full oral feeding and earlier hospital discharge. This finding should be interpreted cautiously because of methodological weaknesses in the included trials. A large randomised controlled trial is needed to confirm this finding and to determine if ad libitum of demand/semi-demand feeding of preterm infants affects other clinically important outcomes.
The Magical Mystery Four: How is Working Memory Capacity Limited, and Why?
Cowan, Nelson
2009-01-01
Working memory storage capacity is important because cognitive tasks can be completed only with sufficient ability to hold information as it is processed. The ability to repeat information depends on task demands but can be distinguished from a more constant, underlying mechanism: a central memory store limited to 3 to 5 meaningful items in young adults. I will discuss why this central limit is important, how it can be observed, how it differs among individuals, and why it may occur. PMID:20445769
Demand for Modern Family Planning among Married Women Living with HIV in Western Ethiopia
Feyissa, Tesfaye Regassa; Melka, Alemu Sufa
2014-01-01
Introduction People living with HIV (PLHIV) have diverse family planning (FP) needs. Little is reported on FP needs among women living with HIV in Ethiopia. Thus, the objective of the study was to assess the demand for modern FP among married women living with HIV in western Ethiopia. Methods A facility-based cross-sectional survey was conducted on 401 married women living with HIV selected from Nekemte Referral Hospital and Health Center, Nekemte, Oromia, Ethiopia. Convenience sampling of every other eligible patient was used to recruit respondents. Data were collected using a pretested, structured questionnaire. We first calculated frequency and percentage of unmet need, met need and total demand by each explanatory variable, and performed chi-squared testing to assess for differences in groups. We then fitted logistic regression models to identify correlates of unmet need for modern FP at 95% CL. Results The proportion of respondents with met need for modern FP among married women living with HIV was 61.6% (30.7% for spacing and 30.9% for limiting). Demand for family planning was reported in 77.0% (38.2% for spacing and 38.8% for limiting), making unmet need for modern FP prevalent in 15.4% (7.5% for spacing and 7.9% for limiting). Whereas age 25–34 years [adjusted odds ratio (AOR) (95% confidence interval (CI)) = .397 (.204–.771)] was protective against unmet need for modern FP, not having knowledge of MTCT [AOR (95% CI) = 2.531 (1.689–9.290)] and not discussing FP with a partner [AOR (95% CI) = 3.616(1.869–6.996)] were associated with increased odds of unmet need for modern FP. Conclusions There is high unmet need for modern FP in HIV-positive married women in western Ethiopia. Health care providers and program managers at a local and international level should work to satisfy the unmet need for modern family planning. PMID:25390620
Demand for modern family planning among married women living with HIV in western Ethiopia.
Feyissa, Tesfaye Regassa; Melka, Alemu Sufa
2014-01-01
People living with HIV (PLHIV) have diverse family planning (FP) needs. Little is reported on FP needs among women living with HIV in Ethiopia. Thus, the objective of the study was to assess the demand for modern FP among married women living with HIV in western Ethiopia. A facility-based cross-sectional survey was conducted on 401 married women living with HIV selected from Nekemte Referral Hospital and Health Center, Nekemte, Oromia, Ethiopia. Convenience sampling of every other eligible patient was used to recruit respondents. Data were collected using a pretested, structured questionnaire. We first calculated frequency and percentage of unmet need, met need and total demand by each explanatory variable, and performed chi-squared testing to assess for differences in groups. We then fitted logistic regression models to identify correlates of unmet need for modern FP at 95% CL. The proportion of respondents with met need for modern FP among married women living with HIV was 61.6% (30.7% for spacing and 30.9% for limiting). Demand for family planning was reported in 77.0% (38.2% for spacing and 38.8% for limiting), making unmet need for modern FP prevalent in 15.4% (7.5% for spacing and 7.9% for limiting). Whereas age 25-34 years [adjusted odds ratio (AOR) (95% confidence interval (CI)) = .397 (.204-.771)] was protective against unmet need for modern FP, not having knowledge of MTCT [AOR (95% CI) = 2.531 (1.689-9.290)] and not discussing FP with a partner [AOR (95% CI) = 3.616(1.869-6.996)] were associated with increased odds of unmet need for modern FP. There is high unmet need for modern FP in HIV-positive married women in western Ethiopia. Health care providers and program managers at a local and international level should work to satisfy the unmet need for modern family planning.
Cantley, Linda F; Tessier-Sherman, Baylah; Slade, Martin D; Galusha, Deron; Cullen, Mark R
2016-04-01
To examine associations between workplace injury and musculoskeletal disorder (MSD) risk and expert ratings of job-level psychosocial demand and job control, adjusting for job-level physical demand. Among a cohort of 9260 aluminium manufacturing workers in jobs for which expert ratings of job-level physical and psychological demand and control were obtained during the 2 years following rating obtainment, multivariate mixed effects models were used to estimate relative risk (RR) of minor injury and minor MSD, serious injury and MSD, minor MSD only and serious MSD only by tertile of demand and control, adjusting for physical demand as well as other recognised risk factors. Compared with workers in jobs rated as having low psychological demand, workers in jobs with high psychological demand had 49% greater risk of serious injury and serious MSD requiring medical treatment, work restrictions or lost work time (RR=1.49; 95% CI 1.10 to 2.01). Workers in jobs rated as having low control displayed increased risk for minor injury and minor MSD (RR=1.45; 95% CI 1.12 to 1.87) compared with those in jobs rated as having high control. Using expert ratings of job-level exposures, this study provides evidence that psychological job demand and job control contribute independently to injury and MSD risk in a blue-collar manufacturing cohort, and emphasises the importance of monitoring psychosocial workplace exposures in addition to physical workplace exposures to promote worker health and safety. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/
Land use and water use in the Antelope Valley, California
Templin, William E.; Phillips, Steven P.; Cherry, Daniel E.; DeBortoli, Myrna L.; Haltom, T.C.; McPherson, Kelly R.; Mrozek, C.A.
1995-01-01
Urban land use and water use in the Antelope Valley, California, have increased significantly since development of the valley began in the late 1800's.. Ground water has been a major source of water in this area because of limited local surface-water resources. Ground-water pumpage is reported to have increased from about 29,000 acre-feet in 1919 to about 400,000 acre-feet in the 1950's. Completion of the California Aqueduct to this area in the early 1970's conveyed water from the Sacramento-San Joaquin Delta, about 400 miles to the north. Declines in groundwater levels and increased costs of electrical power in the 1970's resulted in a reduction in the quantity of ground water that was pumped annually for irrigation uses. Total annual reported ground-water pumpage decreased to a low of about 53,200 acre-feet in 1983 and increased to about 91,700 acre-feet in 1991 as a result of rapid urban development and the 1987-92 drought. This increased urban development, in combination with several years of drought, renewed concern about a possible return to extensive depletion of ground-water storage and increased land subsidence.Increased water demands are expected to continue as a result of increased urban development. Water-demand forecasts in 1980 for the Antelope Valley indicated that total annual water demand by 2020 was expected to be about 250,000 acre-feet, with agricultural demand being about 65 percent of this total. In 1990, total water demand was projected to be about 175,000 acre-feet by 2010; however, agricultural water demand was expected to account for only 37 percent of the total demand. New and existing land- and water-use data were collected and compiled during 1992-93 to identify present and historical land and water uses. In 1993, preliminary forecasts for total water demand by 2010 ranged from about 127,500 to 329,000 acre-feet. These wide-ranging estimates indicate that forecasts can change with time as factors that affect water demand change and different forecasting methods are used. The forecasts using the MWD_MAIN (Metropolitan Water District of Southern California Municipal and Industrial Needs) water-demand forecasting system yielded the largest estimates of water demand. These forecasts were based on projections of population growth and other socioeconomic variables. Initial forecasts using the MWD_MAIN forecasting system commonly are considered "interim" or preliminary. Available historical and future socioeconomic data required for the forecasting system are limited for this area. Decisions on local water-resources demand management may be made by members of the Antelope Valley Water Group and other interested parties based on this report, other studies, their best judgement, and cumulative knowledge of local conditions. Potential water-resource management actions in the Antelope Valley include (1) increasing artificial ground-water recharge when excess local runoff (or imported water supplies) are available; (2) implementing water-conservation best-management practices; and (3) optimizing ground-water pumpage throughout the basin.
Synthesizing Econometric Evidence: The Case of Demand Elasticity Estimates.
DeCicca, Philip; Kenkel, Don
2015-06-01
Econometric estimates of the responsiveness of health-related consumer demand to higher prices are often key ingredients for risk policy analysis. We review the potential advantages and challenges of synthesizing econometric evidence on the price-responsiveness of consumer demand. We draw on examples of research on consumer demand for health-related goods, especially cigarettes. We argue that the overarching goal of research synthesis in this context is to provide policy-relevant evidence for broad-brush conclusions. We propose three main criteria to select among research synthesis methods. We discuss how in principle and in current practice synthesis of research on the price-elasticity of smoking meets our proposed criteria. Our analysis of current practice also contributes to academic research on the specific policy question of the effectiveness of higher cigarette prices to reduce smoking. Although we point out challenges and limitations, we believe more work on research synthesis in this area will be productive and important. © 2015 Society for Risk Analysis.
Data Mining for Understanding and Improving Decision-making Affecting Ground Delay Programs
NASA Technical Reports Server (NTRS)
Kulkarni, Deepak; Wang, Yao; Sridhar, Banavar
2013-01-01
The continuous growth in the demand for air transportation results in an imbalance between airspace capacity and traffic demand. The airspace capacity of a region depends on the ability of the system to maintain safe separation between aircraft in the region. In addition to growing demand, the airspace capacity is severely limited by convective weather. During such conditions, traffic managers at the FAA's Air Traffic Control System Command Center (ATCSCC) and dispatchers at various Airlines' Operations Center (AOC) collaborate to mitigate the demand-capacity imbalance caused by weather. The end result is the implementation of a set of Traffic Flow Management (TFM) initiatives such as ground delay programs, reroute advisories, flow metering, and ground stops. Data Mining is the automated process of analyzing large sets of data and then extracting patterns in the data. Data mining tools are capable of predicting behaviors and future trends, allowing an organization to benefit from past experience in making knowledge-driven decisions.
Modeling complexity in engineered infrastructure system: Water distribution network as an example
NASA Astrophysics Data System (ADS)
Zeng, Fang; Li, Xiang; Li, Ke
2017-02-01
The complex topology and adaptive behavior of infrastructure systems are driven by both self-organization of the demand and rigid engineering solutions. Therefore, engineering complex systems requires a method balancing holism and reductionism. To model the growth of water distribution networks, a complex network model was developed following the combination of local optimization rules and engineering considerations. The demand node generation is dynamic and follows the scaling law of urban growth. The proposed model can generate a water distribution network (WDN) similar to reported real-world WDNs on some structural properties. Comparison with different modeling approaches indicates that a realistic demand node distribution and co-evolvement of demand node and network are important for the simulation of real complex networks. The simulation results indicate that the efficiency of water distribution networks is exponentially affected by the urban growth pattern. On the contrary, the improvement of efficiency by engineering optimization is limited and relatively insignificant. The redundancy and robustness, on another aspect, can be significantly improved through engineering methods.
Kavitha, S; Subbulakshmi, P; Rajesh Banu, J; Gobi, Muthukaruppan; Tae Yeom, Ick
2017-06-01
Generation of bioenergy from microalgal biomass has been a focus of interest in recent years. The recalcitrant nature of microalgal biomass owing to its high cellulose content limits methane generation. Thus, the present study investigates the effect of bacterial-based biological pretreatment on liquefaction of the microalga Chlorella vulgaris prior to anaerobic biodegradation to gain insights into energy efficient biomethanation. Liquefaction of microalgae resulted in a higher biomass stress index of about 18% in the experimental (pretreated with cellulose-secreting bacteria) vs. 11.8% in the control (non-pretreated) group. Mathematical modelling of the biomethanation studies implied that bacterial pretreatment had a greater influence on sustainable methane recovery, with a methane yield of about 0.08 (g Chemical Oxygen Demand/g Chemical Oxygen Demand), than did control pretreatment, with a yield of 0.04 (g Chemical Oxygen Demand/g Chemical Oxygen Demand). Energetic analysis of the proposed method of pretreatment showed a positive energy ratio of 1.04. Copyright © 2017 Elsevier Ltd. All rights reserved.
Towards decision support for waiting lists: an operations management view.
Vissers, J M; Van Der Bij, J D; Kusters, R J
2001-06-01
This paper considers the phenomenon of waiting lists in a healthcare setting, which is characterised by limitations on the national expenditure, to explore the potentials of an operations management perspective. A reference framework for waiting list management is described, distinguishing different levels of planning in healthcare--national, regional, hospital and process--that each contributes to the existence of waiting lists through managerial decision making. In addition, different underlying mechanisms in demand and supply are distinguished, which together explain the development of waiting lists. It is our contention that within this framework a series of situation specific models should be designed to support communication and decision making. This is illustrated by the modelling of the demand for cataract treatment in a regional setting in the south-eastern part of the Netherlands. An input-output model was developed to support decisions regarding waiting lists. The model projects the demand for treatment at a regional level and makes it possible to evaluate waiting list impacts for different scenarios to meet this demand.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hutzler, M.J.
Over the next 20 years, the combination of slow growth in the demand for electricity, even slower growth in the need for new capacity, especially baseload capacity, and the competitiveness of new gas-fired technologies limits the market for new coal technologies in the US. In the later years of the 1997 Annual Energy Outlook projections, post-2005, when a significant amount of new capacity is needed to replace retiring plants and meet growing demand, some new coal-fired plants are expected to be built, but new gas-fired plants are expected to remain the most economical choice for most needs. The largest marketmore » for clean coal technologies in the United States may be in retrofitting or repowering existing plants to meet stricter environmental standards, especially over the next 10 years. Key uncertainties include the rate of growth in the demand for electricity and the level of competing fuel prices, particularly natural gas. Higher than expected growth in the demand for electricity and/or relatively higher natural gas prices would increase the market for new coal technologies.« less
33 CFR 110.214 - Los Angeles and Long Beach harbors, California.
Code of Federal Regulations, 2012 CFR
2012-07-01
... following locations: (A) Inner Harbor: The Henry Ford (Badger Avenue) Bridge. (B) Middle Harbor: The Pier... will be given, but not necessarily limited to: the current and anticipated demands for anchorage space...
33 CFR 110.214 - Los Angeles and Long Beach harbors, California.
Code of Federal Regulations, 2011 CFR
2011-07-01
... following locations: (A) Inner Harbor: The Henry Ford (Badger Avenue) Bridge. (B) Middle Harbor: The Pier... will be given, but not necessarily limited to: the current and anticipated demands for anchorage space...
Code of Federal Regulations, 2010 CFR
2010-10-01
... under section 301. (See 50 U.S.C. App. 2091 for statutory limitations and exceptions concerning the... demand of the lender, to purchase a stated percentage of the loan and to share any losses in the amount...
Code of Federal Regulations, 2011 CFR
2011-10-01
... under section 301. (See 50 U.S.C. App. 2091 for statutory limitations and exceptions concerning the... demand of the lender, to purchase a stated percentage of the loan and to share any losses in the amount...
36 CFR 223.5 - Scope of free use granted to individuals.
Code of Federal Regulations, 2010 CFR
2010-07-01
... immediately adjacent to the National Forest when the available supply is insufficient to meet the total demand... unusual cases where its refusal would cause unwarranted hardship. Where limited supply or other conditions...
Snowplow simulator training evaluation
DOT National Transportation Integrated Search
2006-11-01
Snowplow drivers must operate $200,000 units of equipment in blinding snowstorms and demanding traffic conditions. : Yet traditional training for new drivers, with limited funding and staff, may be only two or three storm shifts with a : partner-trai...
47 CFR 54.709 - Computations of required contributions to universal service support mechanisms.
Code of Federal Regulations, 2013 CFR
2013-10-01
... Commission's website. The Commission reserves the right to set projections of demand and administrative... Administrator has available, including, but not limited to, the number of lines presubscribed to the contributor...
47 CFR 54.709 - Computations of required contributions to universal service support mechanisms.
Code of Federal Regulations, 2012 CFR
2012-10-01
... Commission's website. The Commission reserves the right to set projections of demand and administrative... Administrator has available, including, but not limited to, the number of lines presubscribed to the contributor...
47 CFR 54.709 - Computations of required contributions to universal service support mechanisms.
Code of Federal Regulations, 2014 CFR
2014-10-01
... Commission's website. The Commission reserves the right to set projections of demand and administrative... Administrator has available, including, but not limited to, the number of lines presubscribed to the contributor...
47 CFR 54.709 - Computations of required contributions to universal service support mechanisms.
Code of Federal Regulations, 2011 CFR
2011-10-01
... Commission's website. The Commission reserves the right to set projections of demand and administrative... whatever relevant data the Administrator has available, including, but not limited to, the number of lines...
Evaluation of New Jersey Route 18 OPAC/MIST traffic-control system
DOT National Transportation Integrated Search
1997-01-01
Conventional traffic-control strategies have limitations in handling unanticipated traffic demands. An adaptive traffic-signal control is expected to mitigate this problem and improve overall system performance. Furthermore, with the increasing needs...
Benjamin N. Sulman; Daniel Tyler Roman; Koong Yi; Lixin Wang; Richard P. Phillips; Kimberly A. Novick
2016-01-01
When stressed by low soil water content (SWC) or high vapor pressure deficit (VPD), plants close stomata, reducing transpiration and photosynthesis. However, it has historically been difficult to disentangle the magnitudes of VPD compared to SWC limitations on ecosystem-scale fluxes. We used a 13 year record of eddy covariance measurements from a forest in south...
2011-02-01
almost entirely dependent on the national transmission grid . . . [which] is fragile, vulnerable, near its capacity limit, and outside of DOD control...has returned. A major factor in this resurgence has come from developing countries, where expressed and pro- jected demands for electricity are...rapidly growing and limited infrastructural and investment capacity generates interest in reactors that can be deployed rapidly and in- crementally.14
Heat transfer in aerospace propulsion
NASA Technical Reports Server (NTRS)
Simoneau, Robert J.; Hendricks, Robert C.; Gladden, Herbert J.
1988-01-01
Presented is an overview of heat transfer related research in support of aerospace propulsion, particularly as seen from the perspective of the NASA Lewis Research Center. Aerospace propulsion is defined to cover the full spectrum from conventional aircraft power plants through the Aerospace Plane to space propulsion. The conventional subsonic/supersonic aircraft arena, whether commercial or military, relies on the turbine engine. A key characteristic of turbine engines is that they involve fundamentally unsteady flows which must be properly treated. Space propulsion is characterized by very demanding performance requirements which frequently push systems to their limits and demand tailored designs. The hypersonic flight propulsion systems are subject to severe heat loads and the engine and airframe are truly one entity. The impact of the special demands of each of these aerospace propulsion systems on heat transfer is explored.
Effects of psychosocial work factors on lifestyle changes: a cohort study.
Allard, Karin Olofsson; Thomsen, Jane Frølund; Mikkelsen, Sigurd; Rugulies, Reiner; Mors, Ole; Kærgaard, Anette; Kolstad, Henrik A; Kaerlev, Linda; Andersen, Johan Hviid; Hansen, Ase Marie; Bonde, Jens Peter
2011-12-01
To evaluate the effect of the demand-control-support model, the effort-reward imbalance model, and emotional demands on smoking, alcohol consumption, physical activity, and body mass index. This is a 2-year prospective cohort study of 3224 public sector employees. Measures were assessed with questionnaires. Multiple regression analyses were used to predict changes in lifestyle factors. Low reward predicted smoking, low-decision latitude predicted being inactive, and high demands predicted high-alcohol consumption but only for men at follow-up even after controlling for potential confounders. There were no other significant findings in the expected direction except for some of the confounders. We found only limited and inconsistent support for the hypothesis that a poor psychosocial work environment is associated with an adverse lifestyle.
A low power, on demand electrothermal valve for wireless drug delivery applications
Li, Po-Ying; Givrad, Tina K.; Sheybani, Roya; Holschneider, Daniel P.; Maarek, Jean-Michel I.
2014-01-01
We present a low power, on demand Parylene MEMS electrothermal valve. A novel Ω-shaped thermal resistive element requires low power (~mW) and enables rapid valve opening (~ms). Using both finite element analysis and valve opening experiments, a robust resistive element design for improved valve opening performance in water was obtained. In addition, a thermistor, as an inrush current limiter, was added into the valve circuit to provide variable current ramping. Wireless activation of the valve using RF inductive power transfer was demonstrated. PMID:20024057
Water quality management using statistical analysis and time-series prediction model
NASA Astrophysics Data System (ADS)
Parmar, Kulwinder Singh; Bhardwaj, Rashmi
2014-12-01
This paper deals with water quality management using statistical analysis and time-series prediction model. The monthly variation of water quality standards has been used to compare statistical mean, median, mode, standard deviation, kurtosis, skewness, coefficient of variation at Yamuna River. Model validated using R-squared, root mean square error, mean absolute percentage error, maximum absolute percentage error, mean absolute error, maximum absolute error, normalized Bayesian information criterion, Ljung-Box analysis, predicted value and confidence limits. Using auto regressive integrated moving average model, future water quality parameters values have been estimated. It is observed that predictive model is useful at 95 % confidence limits and curve is platykurtic for potential of hydrogen (pH), free ammonia, total Kjeldahl nitrogen, dissolved oxygen, water temperature (WT); leptokurtic for chemical oxygen demand, biochemical oxygen demand. Also, it is observed that predicted series is close to the original series which provides a perfect fit. All parameters except pH and WT cross the prescribed limits of the World Health Organization /United States Environmental Protection Agency, and thus water is not fit for drinking, agriculture and industrial use.
Estimating the Marginal Effect of Socioeconomic Factors on the Demand of Specialty Drugs
Jebeli, Seyede Sedighe Hosseini; Barouni, Mohsen; Orojloo, Parvane Heidari; Mehraban, Sattar
2015-01-01
Given the growing importance and role of drugs in the treatment of diseases, as well as replacement of them rather than expensive and often unsafe procedures, study of socioeconomicfactors affecting future demand for them seems necessary. we seek to examine the extent of to which socioeconomic factors affect specialty medicine use by the patients.using data from questionnaires completed by 280 patients with multiple sclerosis, hemophilia, thalassemia, and chronic kidney disease, we estimate marginal effect of significant variables in probitmodel. We found that the need for the patient(ME=0.858), deterioration of the patient (ME=-0.001), household size (ME =0.0004), House Ownership (ME=-0.002), gender (ME=-0.04), income (ME=-0.0007), education (ME=-0.0021) and job (ME=-0.0021) are significant variables affecting demand for specialty drugs. We conclude that it can be programmed to promote and protect the welfare of patients by specific factors such as income, and largely affect the demand of medication and medical services. Therefore economic aid to these patients should not be limited only to medical subsidies, especially in patients with MS, income and welfare can reduce drug demand. PMID:25716405
Demands and resources: parents of school-age children with asthma.
Lee, E Juanita; Parker, Veronica; DuBose, Lisa; Gwinn, Jane; Logan, Barbara N
2006-12-01
Asthma is one of the most common chronic diseases in children and is frequently noted as the reason for school absences. The purpose of this pilot study was to determine the differences in demands and resources reported by African American (AA) and European American (EA) parents of school-age children with asthma. A convenience sample of 37 parents participated in the study. Data were collected from 19 AA and 18 EA parents. Family stress theory provided the framework for this study. All subjects completed a demographic questionnaire, the Care of My Child With Asthma Scale, and the Family Inventory of Resources for Management (FIRM). Descriptive statistics were used to analyze the data. The most time-consuming caregiving demand reported by EA parents was providing emotional support for the child. For AA parents, the most time-consuming caregiving demand was managing work or school outside the home and organizing asthma treatments at the same time. AA parents had limited resources in the area of extended family social support. The Mann-Whitney U test found no statistically significant differences between AA and EA parents in relation to demands and resources. Nursing implications are presented.
Estimating the marginal effect of socioeconomic factors on the demand of specialty drugs.
Hosseini Jebeli, Seyede Sedighe; Barouni, Mohsen; Orojloo, Parvane Heidari; Mehraban, Sattar
2014-09-25
Given the growing importance and role of drugs in the treatment of diseases, as well as replacement of them rather than expensive and often unsafe procedures, study of socioeconomicfactors affecting future demand for them seems necessary.we seek to examine the extent of to which socioeconomic factors affect specialty medicine use by the patients.using data from questionnaires completed by 280 patients with multiple sclerosis, hemophilia, thalassemia, and chronic kidney disease, we estimate marginal effect of significant variables in probit model.We found that the need for the patient(ME = 0.858), deterioration of the patient (ME = -0.001), household size (ME = 0.0004), House Ownership (ME = -0.002), gender (ME = -0.04), income (ME = -0.0007), education (ME = -0.0021) and job (ME = -0.0021) are significant variables affecting demand for specialty drugs. We conclude that it can be programmed to promote and protect the welfare of patients by specific factors such as income, and largely affect the demand of medication and medical services. Therefore economic aid to these patients should not be limited only to medical subsidies, especially in patients with MS, income and welfare can reduce drug demand.
Occupational demand and human rights. Public safety officers and cardiorespiratory fitness.
Shephard, R J
1991-08-01
The issue of discrimination in physically demanding employment, such as police, firefighters, prison guards and military personnel, is contentious. In terms of oxygen transport, the 'action limit' (calling for personnel selection or task redesign) is a steady oxygen consumption of 0.7 L/min, while the maximum permissible limit is 2.1 L/min. Note is taken of the commonly expressed belief that public safety duties are physically demanding, calling for personnel with an aerobic power of at least 3 L/min, or 42 to 45 ml/kg/min. The actual demands of such work can be assessed on small samples by physiological measurements (using heart rate or oxygen consumption meters), but the periods sampled may not be typical of a normal day. A Gestalt can also be formed as to the heaviness of a given job, or a detailed task analysis can be performed; most such analyses of public safety work list distance running and other aerobic activities infrequently. An arbitrary requirement of 'above average fitness' is no longer accepted by courts, but a further approach is to examine the characteristics of those currently meeting the demands of public safety jobs satisfactorily. Young men commonly satisfy the 3 L/min standard, but this is not usually the case for women or older men; in the case of female employees, it also seems unreasonable that they should be expected to satisfy the same standards as men, since a lower body mass reduces the energy cost of most of the tasks that they must perform. A second criterion sometimes applied to physically demanding work (a low vulnerability to heart attacks) is examined critically. It is concluded that the chances that a symptom-free public safety officer will develop a heart attack during a critical solo mission are so low that cardiac risk should not be a condition of employment. Arbitrary age- and sex-related employment criteria are plainly discriminatory, since some women and 65-year-old men have higher levels of physical fitness than the average young man of 25 years. Neither laboratory nor field tests offer a satisfactory means of distinguishing such individuals, and the only equitable basis of selecting personnel for physically demanding work seems a probationary period of employment.
Developing a remote practice office.
D'Elia, V L
1987-11-01
Remote practice offices (RPOs) offer unique opportunities for hospitals and physicians to increase market share from targeted areas where previously only limited demand existed. This article discusses the benefits and explores the fundamentals of developing a remote practice office.
Advanced tools for irrigation scheduling
USDA-ARS?s Scientific Manuscript database
Irrigated agriculture is needed to meet demands for agricultural products, but farmers are challenged with limited quality water supplies, environmental and regulatory policies climate variability, and competition for water from other sectors. Scientific irrigation scheduling could help allay these ...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lindsay, I.
The author limits his remarks to a discussion of the international generator`s marketplace, especially aimed at the developing countries. He discusses future global electricity demand, generating capacity build, its financing issues, and to the commercial generating opportunities which now abound outside the US.
Positive feedback : exploring current approaches in iterative travel demand model implementation.
DOT National Transportation Integrated Search
2012-01-01
Currently, the models that TxDOTs Transportation Planning and Programming Division (TPP) developed are : traditional three-step models (i.e., trip generation, trip distribution, and traffic assignment) that are sequentially : applied. A limitation...
SUPERVISORY CONTROL FOR PEAK REDUCTION IN COMMERCIAL BUILDINGS WHILE MAINTAINING COMFORT
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nutaro, James J; Olama, Mohammed M; Kuruganti, Teja
2016-01-01
This paper describes a supervisory control strategy for limiting peak power demand by small and medium commercial buildings while still meeting the business needs of the occupants. This control strategy has two features that make it relevant to new and existing buildings. First, it is designed to operate with building equipment, such as air conditioning and refrigeration systems, as they are presently installed in most small and medium commercial buildings. Because of this, the supervisory control could be realized as a software-only retrofit to existing building management systems. Second, the proposed control acts as a supervisory management layer over existingmore » control systems, rather than replacing them outright. The primary idea of this approach is that the controls for individual building equipment request energy resources for a control action and the supervisory control examines the requests and decides which control actions to allow while satisfying a limit on peak power demand.« less
Empirical Investigations of the Opportunity Limits of Automatic Residential Electric Load Shaping
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cruickshank, Robert F.; Henze, Gregor P.; Balaji, Rajagopalan
Residential electric load shaping is often modeled as infrequent, utility-initiated, short-duration deferral of peak demand through direct load control. In contrast, modeled herein is the potential for frequent, transactive, intraday, consumer-configurable load shaping for storage-capable thermostatically controlled electric loads (TCLs), including refrigerators, freezers, and hot water heaters. Unique to this study are 28 months of 15-minute-interval observations of usage in 101 homes in the Pacific Northwest United States that specify exact start, duration, and usage patterns of approximately 25 submetered loads per home. The magnitudes of the load shift from voluntarily-participating TCL appliances are aggregated to form hourly upper andmore » lower load-shaping limits for the coordination of electrical generation, transmission, distribution, storage, and demand. Empirical data are statistically analyzed to define metrics that help quantify load-shaping opportunities.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cruickshank, Robert F.; Henze, Gregor P.; Balaji, Rajagopalan
Residential electric load shaping is often modeled as infrequent, utility-initiated, short-duration deferral of peak demand through direct load control. In contrast, modeled herein is the potential for frequent, transactive, intraday, consumer-configurable load shaping for storage-capable thermostatically controlled electric loads (TCLs), including refrigerators, freezers, and hot water heaters. Unique to this study are 28 months of 15-minute-interval observations of usage in 101 homes in the Pacific Northwest United States that specify exact start, duration, and usage patterns of approximately 25 submetered loads per home. The magnitudes of the load shift from voluntarily-participating TCL appliances are aggregated to form hourly upper andmore » lower load-shaping limits for the coordination of electrical generation, transmission, distribution, storage, and demand. Empirical data are statistically analyzed to define metrics that help quantify load-shaping opportunities.« less
Vegetative community control of freshwater availability: Phoenix Islands case study
NASA Astrophysics Data System (ADS)
Engels, M.; Heinse, R.
2014-12-01
On small low islands with limited freshwater resources, terrestrial plant communities play a large role in moderating freshwater availability. Freshwater demands of vegetative communities are variable depending on the composition of the community. Hence, changes to community structure from production crop introductions, non-native species invasions, and climate change, may have significant implications for freshwater availability. Understanding how vegetative community changes impact freshwater availability will allow for better management and forecasting of limited freshwater supplies. To better understand these dynamics, we investigated three small tropical atolls in the Phoenix Island Protected Area, Kiribati. Despite their close proximity, these islands receive varying amounts of rainfall, are host to different plant communities and two of the islands have abandoned coconut plantations. Using electromagnetic induction, ground penetrating radar, soil samples, climate and satellite data, we present preliminary estimates of vegetative water demand for different tropical plant communities.
Richardson, Leslie; Huber, Christopher; Loomis, John
2017-01-01
Remote and unique destinations present difficulties when attempting to construct traditional travel cost models to value recreation demand. The biggest limitation comes from the lack of variation in the dependent variable, defined as the number of trips taken over a set time frame. There are various approaches that can be used for overcoming limitations of the traditional travel cost model in the context of remote destinations. This study applies an adaptation of the standard model to estimate recreation benefits of bear viewing at Katmai National Park and Preserve in Alaska, which represents a once-in-a-lifetime experience for many visitors. Results demonstrate that visitors to this park’s Brooks Camp area are willing to pay an average of US$287 per day of bear viewing. Implications of these findings for valuing recreation at other remote destinations are discussed.
Kozma, Eszter; Demeter, Orsolya; Kele, Péter
2017-03-16
Bio-orthogonal labelling schemes based on inverse-electron-demand Diels-Alder (IEDDA) cycloaddition have attracted much attention in chemical biology recently. The appealing features of this reaction, such as the fast reaction kinetics, fully bio-orthogonal nature and high selectivity, have helped chemical biologists gain deeper understanding of biochemical processes at the molecular level. Listing the components and discussing the possibilities and limitations of these reagents, we provide a recent snapshot of the field of IEDDA-based biomolecular manipulation with special focus on fluorescent modulation approaches through the use of bio-orthogonalized building blocks. At the end, we discuss challenges that need to be addressed for further developments in order to overcome recent limitations and to enable researchers to answer biomolecular questions in more detail. © 2017 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.
Exploring the biophysical option space for feeding the world without deforestation.
Erb, Karl-Heinz; Lauk, Christian; Kastner, Thomas; Mayer, Andreas; Theurl, Michaela C; Haberl, Helmut
2016-04-19
Safeguarding the world's remaining forests is a high-priority goal. We assess the biophysical option space for feeding the world in 2050 in a hypothetical zero-deforestation world. We systematically combine realistic assumptions on future yields, agricultural areas, livestock feed and human diets. For each scenario, we determine whether the supply of crop products meets the demand and whether the grazing intensity stays within plausible limits. We find that many options exist to meet the global food supply in 2050 without deforestation, even at low crop-yield levels. Within the option space, individual scenarios differ greatly in terms of biomass harvest, cropland demand and grazing intensity, depending primarily on the quantitative and qualitative aspects of human diets. Grazing constraints strongly limit the option space. Without the option to encroach into natural or semi-natural land, trade volumes will rise in scenarios with globally converging diets, thereby decreasing the food self-sufficiency of many developing regions.
Fabre, Julie; Ruelland, Denis; Dezetter, Alain; ...
2016-08-02
This paper assesses the sustainability of planned water uses in mesoscale river basins under multiple climate change scenarios, and contributes to determining the possible causes of unsustainability. We propose an assessment grounded in real-world water management issues, with water management scenarios built in collaboration with local water agencies. Furthermore, we present an analysis through indicators that relate to management goals and present the implications of climate uncertainty for our results, furthering the significance of our study for water management. A modeling framework integrating hydro-climatic and human dynamics and accounting for interactions between resource and demand was applied in two basinsmore » of different scales and with contrasting water uses: the Herault (2500 km 2, France) and the Ebro (85 000 km 2, Spain) basins. Natural streamflow was evaluated using a conceptual hydrological model. A demand-driven reservoir management model was designed to account for streamflow regulations from the main dams. Human water demand was estimated from time series of demographic, socioeconomic and climatic data. Environmental flows were accounted for by defining streamflow thresholds under which withdrawals were strictly limited. Finally indicators comparing water availability to demand at strategic resource and demand nodes were computed. This framework was applied under different combinations of climatic and water use scenarios for the mid-21st to differentiate the impacts of climate- and human-induced changes on streamflow and water balance. Results showed that objective monthly environmental flows would be guaranteed in current climate conditions in both basins, yet in several areas this could imply limiting human water uses more than once every 5 years. The impact of the tested climate projections on both water availability and demand could question the water allocations and environmental requirements currently planned for the coming decades. Water shortages for human use could become more frequent and intense, and the pressure on water resources and aquatic ecosystems could intensify. Furthermore, the causes of unsustainability vary across sub-basins and scenarios, and in most areas results are highly dependent on the climate change scenario.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fabre, Julie; Ruelland, Denis; Dezetter, Alain
This paper assesses the sustainability of planned water uses in mesoscale river basins under multiple climate change scenarios, and contributes to determining the possible causes of unsustainability. We propose an assessment grounded in real-world water management issues, with water management scenarios built in collaboration with local water agencies. Furthermore, we present an analysis through indicators that relate to management goals and present the implications of climate uncertainty for our results, furthering the significance of our study for water management. A modeling framework integrating hydro-climatic and human dynamics and accounting for interactions between resource and demand was applied in two basinsmore » of different scales and with contrasting water uses: the Herault (2500 km 2, France) and the Ebro (85 000 km 2, Spain) basins. Natural streamflow was evaluated using a conceptual hydrological model. A demand-driven reservoir management model was designed to account for streamflow regulations from the main dams. Human water demand was estimated from time series of demographic, socioeconomic and climatic data. Environmental flows were accounted for by defining streamflow thresholds under which withdrawals were strictly limited. Finally indicators comparing water availability to demand at strategic resource and demand nodes were computed. This framework was applied under different combinations of climatic and water use scenarios for the mid-21st to differentiate the impacts of climate- and human-induced changes on streamflow and water balance. Results showed that objective monthly environmental flows would be guaranteed in current climate conditions in both basins, yet in several areas this could imply limiting human water uses more than once every 5 years. The impact of the tested climate projections on both water availability and demand could question the water allocations and environmental requirements currently planned for the coming decades. Water shortages for human use could become more frequent and intense, and the pressure on water resources and aquatic ecosystems could intensify. Furthermore, the causes of unsustainability vary across sub-basins and scenarios, and in most areas results are highly dependent on the climate change scenario.« less
Zhao, Chang; Sander, Heather A.
2015-01-01
Studies that assess the distribution of benefits provided by ecosystem services across urban areas are increasingly common. Nevertheless, current knowledge of both the supply and demand sides of ecosystem services remains limited, leaving a gap in our understanding of balance between ecosystem service supply and demand that restricts our ability to assess and manage these services. The present study seeks to fill this gap by developing and applying an integrated approach to quantifying the supply and demand of a key ecosystem service, carbon storage and sequestration, at the local level. This approach follows three basic steps: (1) quantifying and mapping service supply based upon Light Detection and Ranging (LiDAR) processing and allometric models, (2) quantifying and mapping demand for carbon sequestration using an indicator based on local anthropogenic CO2 emissions, and (3) mapping a supply-to-demand ratio. We illustrate this approach using a portion of the Twin Cities Metropolitan Area of Minnesota, USA. Our results indicate that 1735.69 million kg carbon are stored by urban trees in our study area. Annually, 33.43 million kg carbon are sequestered by trees, whereas 3087.60 million kg carbon are emitted by human sources. Thus, carbon sequestration service provided by urban trees in the study location play a minor role in combating climate change, offsetting approximately 1% of local anthropogenic carbon emissions per year, although avoided emissions via storage in trees are substantial. Our supply-to-demand ratio map provides insight into the balance between carbon sequestration supply in urban trees and demand for such sequestration at the local level, pinpointing critical locations where higher levels of supply and demand exist. Such a ratio map could help planners and policy makers to assess and manage the supply of and demand for carbon sequestration. PMID:26317530
Stadin, Magdalena; Nordin, Maria; Broström, Anders; Magnusson Hanson, Linda L; Westerlund, Hugo; Fransson, Eleonor I
2016-10-01
The use of information and communication technology (ICT) is common in modern working life. ICT demands may give rise to experience of work-related stress. Knowledge about ICT demands in relation to other types of work-related stress and to self-rated health is limited. Consequently, the aim of this study was to examine the association between ICT demands and two types of work-related stress [job strain and effort-reward imbalance (ERI)] and to evaluate the association between these work-related stress measures and self-rated health, in general and in different SES strata. This study is based on cross-sectional data from the Swedish Longitudinal Occupational Survey of Health collected in 2014, from 14,873 gainfully employed people. ICT demands, job strain, ERI and self-rated health were analysed as the main measures. Sex, age, SES, lifestyle factors and BMI were used as covariates. ICT demands correlated significantly with the dimensions of the job strain and ERI models, especially with the demands (r = 0.42; p < 0.01) and effort (r = 0.51; p < 0.01) dimensions. ICT demands were associated with suboptimal self-rated health, also after adjustment for age, sex, SES, lifestyle and BMI (OR 1.49 [95 % CI 1.36-1.63]), but job strain (OR 1.93 [95 % CI 1.74-2.14) and ERI (OR 2.15 [95 % CI 1.95-2.35]) showed somewhat stronger associations with suboptimal self-rated health. ICT demands are common among people with intermediate and high SES and associated with job strain, ERI and suboptimal self-rated health. ICT demands should thus be acknowledged as a potential stressor of work-related stress in modern working life.
Bayerdörffer, Ekkehard; Bigard, Marc-Andre; Weiss, Werner; Mearin, Fermín; Rodrigo, Luis; Dominguez Muñoz, Juan Enrique; Grundling, Hennie; Persson, Tore; Svedberg, Lars-Erik; Keeling, Nanna; Eklund, Stefan
2016-04-14
Most patients with gastroesophageal reflux disease experience symptomatic relapse after stopping acid-suppressive medication. The aim of this study was to compare willingness to continue treatment with esomeprazole on-demand versus continuous maintenance therapy for symptom control in patients with non-erosive reflux disease (NERD) after 6 months. This multicenter, open-label, randomized, parallel-group study enrolled adults with NERD who were heartburn-free after 4 weeks' treatment with esomeprazole 20 mg daily. Patients received esomeprazole 20 mg daily continuously or on-demand for 6 months. The primary variable was discontinuation due to unsatisfactory treatment. On-demand treatment was considered non-inferior if the upper limit of the one-sided 95 % confidence interval (CI) for the difference between treatments was <10 %. Of 877 patients enrolled, 598 were randomized to maintenance treatment (continuous: n = 297; on-demand: n = 301). Discontinuation due to unsatisfactory treatment was 6.3 % for on-demand and 9.8 % for continuous treatment (difference -3.5 % [90 % CI: -7.1 %, 0.2 %]). In total, 82.1 and 86.2 % of patients taking on-demand and continuous therapy, respectively, were satisfied with the treatment of heartburn and regurgitation symptoms, a secondary variable (P = NS). Mean study drug consumption was 0.41 and 0.91 tablets/day, respectively. Overall, 5 % of the on-demand group developed reflux esophagitis versus none in the continuous group (P < 0.0001). The Gastrointestinal Symptom Rating Scale Reflux dimension was also improved for continuous versus on-demand treatment. Esomeprazole was well tolerated. In terms of willingness to continue treatment, on-demand treatment with esomeprazole 20 mg was non-inferior to continuous maintenance treatment and reduced medication usage in patients with NERD who had achieved symptom control with initial esomeprazole treatment. ClinicalTrials.gov identifier (NCT number): NCT02670642 ; Date of registration: December 2015.
Hildebrand, Sean
This article examines local emergency manager's beliefs regarding control over tasks during various stages of the hazard cycle since federal policies went into effect following the September 11 attacks. The study considers whether a disparity exists between the actions of local officials during each phase of the "hazard cycle" and the policy expectations of the federal government, which call for greater federal control over activities in emergency management and homeland security. To do so, hypothesis testing investigates the jurisdiction's use of comprehensive emergency management (CEM) practices, the perceived "clarity" of the federal policy demands, and if the local actors feel coerced to comply with federal policy demands so that grant funding is not compromised. Using a model developed from "third-generation" policy implementation research, the results show that the odds of local officials citing federal control over these actions have very limited statistical significance. This signals that the perceived lack of local input into the development of these federal policies and the policies' limited use of traditional CEM measures may not be in concert with what local actors perform in the field. Simply put, the respondents claim to understand the federal policy demands, support the concept of federal control as the policies describe, yet follow their own plans or traditional CEM principles, even if such actions do not support the federal policy demands. These results align with pre-existing research in the emergency management field that show issues with efforts to centralize policies under the Department of Homeland Security and Federal Emergency Management Agency.
Skiles, Martha Priedeman; Cunningham, Marc; Inglis, Andrew; Wilkes, Becky; Hatch, Ben; Bock, Ariella; Barden-O'Fallon, Janine
2015-03-01
Previous studies have identified positive relationships between geographic proximity to family planning services and contraceptive use, but have not accounted for the effect of contraceptive supply reliability or the diminishing influence of facility access with increasing distance. Kernel density estimation was used to geographically link Malawi women's use of injectable contraceptives and demand for birth spacing or limiting, as drawn from the 2010 Demographic and Health Survey, with contraceptive logistics data from family planning service delivery points. Linear probability models were run to identify associations between access to injectable services-measured by distance alone and by distance combined with supply reliability-and injectable use and family planning demand among rural and urban populations. Access to services was an important predictor of injectable use. The probability of injectable use among rural women with the most access by both measures was 7‒8 percentage points higher than among rural dwellers with the least access. The probability of wanting to space or limit births among urban women who had access to the most reliable supplies was 18 percentage points higher than among their counterparts with the least access. Product availability in the local service environment plays a critical role in women's demand for and use of contraceptive methods. Use of kernel density estimation in creating facility service environments provides a refined approach to linking women with services and accounts for both distance to facilities and supply reliability. Urban and rural differences should be considered when seeking to improve contraceptive access.
Ida, Takashi Y.; Harder, Lawrence D.; Kudo, Gaku
2012-01-01
Background The production of flowers, fruits and seeds demands considerable energy and nutrients, which can limit the allocation of these resources to other plant functions and, thereby, influence survival and future reproduction. The magnitude of the physiological costs of reproduction depends on both the factors limiting seed production (pollen, ovules or resources) and the capacity of plants to compensate for high resource demand. Methods To assess the magnitude and consequences of reproductive costs, we used shading and defoliation to reduce photosynthate production by fully pollinated plants of a perennial legume, Oxytropis sericea (Fabaceae), and examined the resulting impact on photosynthate allocation, and nectar, fruit and seed production. Key Results Although these leaf manipulations reduced photosynthesis and nectar production, they did not alter photosynthate allocation, as revealed by 13C tracing, or fruit or seed production. That photosynthate allocation to reproductive organs increased >190 % and taproot mass declined by 29 % between flowering and fruiting indicates that reproduction was physiologically costly. Conclusions The insensitivity of fruit and seed production to leaf manipulation is consistent with either compensatory mobilization of stored resources or ovule limitation. Seed production differed considerably between the two years of the study in association with contrasting precipitation prior to flowering, perhaps reflecting contrasting limits on reproductive performance. PMID:22021817
Reimer, Bryan; Mehler, Bruce; Reagan, Ian; Kidd, David; Dobres, Jonathan
2016-01-01
Abstract There is limited research on trade-offs in demand between manual and voice interfaces of embedded and portable technologies. Mehler et al. identified differences in driving performance, visual engagement and workload between two contrasting embedded vehicle system designs (Chevrolet MyLink and Volvo Sensus). The current study extends this work by comparing these embedded systems with a smartphone (Samsung Galaxy S4). None of the voice interfaces eliminated visual demand. Relative to placing calls manually, both embedded voice interfaces resulted in less eyes-off-road time than the smartphone. Errors were most frequent when calling contacts using the smartphone. The smartphone and MyLink allowed addresses to be entered using compound voice commands resulting in shorter eyes-off-road time compared with the menu-based Sensus but with many more errors. Driving performance and physiological measures indicated increased demand when performing secondary tasks relative to ‘just driving’, but were not significantly different between the smartphone and embedded systems. Practitioner Summary: The findings show that embedded system and portable device voice interfaces place fewer visual demands on the driver than manual interfaces, but they also underscore how differences in system designs can significantly affect not only the demands placed on drivers, but also the successful completion of tasks. PMID:27110964
NASA Astrophysics Data System (ADS)
Meacham, James R.; Jabbari, Faryar; Brouwer, Jacob; Mauzey, Josh L.; Samuelsen, G. Scott
Current high temperature fuel cell (HTFC) systems used for stationary power applications (in the 200-300 kW size range) have very limited dynamic load following capability or are simply base load devices. Considering the economics of existing electric utility rate structures, there is little incentive to increase HTFC ramping capability beyond 1 kWs -1 (0.4% s -1). However, in order to ease concerns about grid instabilities from utility companies and increase market adoption, HTFC systems will have to increase their ramping abilities, and will likely have to incorporate electrical energy storage (EES). Because batteries have low power densities and limited lifetimes in highly cyclic applications, ultra capacitors may be the EES medium of choice. The current analyses show that, because ultra capacitors have a very low energy storage density, their integration with HTFC systems may not be feasible unless the fuel cell has a ramp rate approaching 10 kWs -1 (4% s -1) when using a worst-case design analysis. This requirement for fast dynamic load response characteristics can be reduced to 1 kWs -1 by utilizing high resolution demand data to properly size ultra capacitor systems and through demand management techniques that reduce load volatility.
Limitations of demand- and pressure-driven modeling for large deficient networks
NASA Astrophysics Data System (ADS)
Braun, Mathias; Piller, Olivier; Deuerlein, Jochen; Mortazavi, Iraj
2017-10-01
The calculation of hydraulic state variables for a network is an important task in managing the distribution of potable water. Over the years the mathematical modeling process has been improved by numerous researchers for utilization in new computer applications and the more realistic modeling of water distribution networks. But, in spite of these continuous advances, there are still a number of physical phenomena that may not be tackled correctly by current models. This paper will take a closer look at the two modeling paradigms given by demand- and pressure-driven modeling. The basic equations are introduced and parallels are drawn with the optimization formulations from electrical engineering. These formulations guarantee the existence and uniqueness of the solution. One of the central questions of the French and German research project ResiWater is the investigation of the network resilience in the case of extreme events or disasters. Under such extraordinary conditions where models are pushed beyond their limits, we talk about deficient network models. Examples of deficient networks are given by highly regulated flow, leakage or pipe bursts and cases where pressure falls below the vapor pressure of water. These examples will be presented and analyzed on the solvability and physical correctness of the solution with respect to demand- and pressure-driven models.
Response terminated displays unload selective attention
Roper, Zachary J. J.; Vecera, Shaun P.
2013-01-01
Perceptual load theory successfully replaced the early vs. late selection debate by appealing to adaptive control over the efficiency of selective attention. Early selection is observed unless perceptual load (p-Load) is sufficiently low to grant attentional “spill-over” to task-irrelevant stimuli. Many studies exploring load theory have used limited display durations that perhaps impose artificial limits on encoding processes. We extended the exposure duration in a classic p-Load task to alleviate temporal encoding demands that may otherwise tax mnemonic consolidation processes. If the load effect arises from perceptual demands alone, then freeing-up available mnemonic resources by extending the exposure duration should have little effect. The results of Experiment 1 falsify this prediction. We observed a reliable flanker effect under high p-Load, response-terminated displays. Next, we orthogonally manipulated exposure duration and task-relevance. Counter-intuitively, we found that the likelihood of observing the flanker effect under high p-Load resides with the duration of the task-relevant array, not the flanker itself. We propose that stimulus and encoding demands interact to produce the load effect. Our account clarifies how task parameters differentially impinge upon cognitive processes to produce attentional “spill-over” by appealing to visual short-term memory as an additional processing bottleneck when stimuli are briefly presented. PMID:24399983
Response terminated displays unload selective attention.
Roper, Zachary J J; Vecera, Shaun P
2013-01-01
Perceptual load theory successfully replaced the early vs. late selection debate by appealing to adaptive control over the efficiency of selective attention. Early selection is observed unless perceptual load (p-Load) is sufficiently low to grant attentional "spill-over" to task-irrelevant stimuli. Many studies exploring load theory have used limited display durations that perhaps impose artificial limits on encoding processes. We extended the exposure duration in a classic p-Load task to alleviate temporal encoding demands that may otherwise tax mnemonic consolidation processes. If the load effect arises from perceptual demands alone, then freeing-up available mnemonic resources by extending the exposure duration should have little effect. The results of Experiment 1 falsify this prediction. We observed a reliable flanker effect under high p-Load, response-terminated displays. Next, we orthogonally manipulated exposure duration and task-relevance. Counter-intuitively, we found that the likelihood of observing the flanker effect under high p-Load resides with the duration of the task-relevant array, not the flanker itself. We propose that stimulus and encoding demands interact to produce the load effect. Our account clarifies how task parameters differentially impinge upon cognitive processes to produce attentional "spill-over" by appealing to visual short-term memory as an additional processing bottleneck when stimuli are briefly presented.
2014 Wind Technologies Market Report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wiser, Ryan; Bolinger, Mark; Barbose, Galen
Wind power capacity additions in the United States rebounded in 2014, and continued growth through 2016 is anticipated. Recent and projected near-term growth is supported by the industry’s primary federal incentive—the production tax credit (PTC)—which is available for projects that began construction by the end of 2014. Wind additions are also being driven by recent improvements in the cost and performance of wind power technologies, which have resulted in the lowest power sales prices ever seen in the U.S. wind sector. Growing corporate demand for wind energy and state-level policies play important roles as well. Expectations for continued technological advancementsmore » and cost reductions may further boost future growth. At the same time, the prospects for growth beyond 2016 are uncertain. The PTC has expired, and its renewal remains in question. Continued low natural gas prices, modest electricity demand growth, and limited near-term demand from state renewables portfolio standards (RPS) have also put a damper on growth expectations. These trends, in combination with increasingly global supply chains, have limited the growth of domestic manufacturing of wind equipment. What they mean for wind power additions through the end of the decade and beyond will be dictated in part by future natural gas prices, fossil plant retirements, and policy decisions.« less
Significance of dissolved methane in effluents of anaerobically ...
The need for energy efficient Domestic Wastewater (DWW) treatment is increasing annually with population growth and expanding global energy demand. Anaerobic treatment of low strength DWW produces methane which can be used to as an energy product. Temperature sensitivity, low removal efficiencies (Chemical Oxygen Demand (COD), Suspended Solids (SS), and Nutrients), alkalinity demand, and potential greenhouse gas (GHG) emissions have limited its application to warmer climates. Although well designed anaerobic Membrane Bioreactors (AnMBRs) are able to effectively treat DWW at psychrophilic temperatures (10–30 °C), lower temperatures increase methane solubility leading to increased energy losses in the form of dissolved methane in the effluent. Estimates of dissolved methane losses are typically based on concentrations calculated using Henry's Law but advection limitations can lead to supersaturation of methane between 1.34 and 6.9 times equilibrium concentrations and 11–100% of generated methane being lost in the effluent. In well mixed systems such as AnMBRs which use biogas sparging to control membrane fouling, actual concentrations approach equilibrium values. Non-porous membranes have been used to recover up to 92.6% of dissolved methane and well suited for degassing effluents of Upflow Anaerobic Sludge Blanket (UASB) reactors which have considerable solids and organic contents and can cause pore wetting and clogging in microporous membrane modules. Micro
Population perspectives on the causes of international migration.
Stahl, C
1987-06-01
The paper considers the causes of international voluntary labor migration from the economic perspective of supply of and demand for labor force. Changing global economic forces figure in the relevant decisions of individuals, industries, and countries. The author 1st examines global economic forces responsible for creating an unlimited supply of migrant labor within the 3rd world ready to work abroad. Reasons why a marked proportion of international labor migration is sourced in a limited number of countries are then discussed, followed by consideration of selectivity factors for laborers coming from certain subpopulations within given countries. Economic forces supporting demand for labor in countries of immigration are then discussed, with attention to the limits of growth in demand. The author concludes that immigration policies of comparatively wealthy countries determine the magnitude of international labor migration. These policies, however, are developed on the basis of perceived labor needs of the country, and are subject to become more restrictive as foreign workers increasingly impose upon the cultural space of the indigenous population. Restricting further immigration to workers only, not their dependents, is not encouraged as viable policy. Further discussion is included on increasing international economic inequalities resulting from international labor migration, and the role of source countries in ensuring the provision of suitable working conditions for immigrant workers.
Modeling and analysis of the effect of training on V O2 kinetics and anaerobic capacity.
Stirling, J R; Zakynthinaki, M S; Billat, V
2008-07-01
In this paper, we present an application of a number of tools and concepts for modeling and analyzing raw, unaveraged, and unedited breath-by-breath oxygen uptake data. A method for calculating anaerobic capacity is used together with a model, in the form of a set of coupled nonlinear ordinary differential equations to make predictions of the VO(2) kinetics, the time to achieve a percentage of a certain constant oxygen demand, and the time limit to exhaustion at intensities other than those in which we have data. Speeded oxygen kinetics and increased time limit to exhaustion are also investigated using the eigenvalues of the fixed points of our model. We also use a way of analyzing the oxygen uptake kinetics using a plot of V O(2)(t) vs V O(2)(t) which allows one to observe both the fixed point solutions and also the presence of speeded oxygen kinetics following training. A method of plotting the eigenvalue versus oxygen demand is also used which allows one to observe where the maximum amplitude of the so-called slow component will be and also how training has changed the oxygen uptake kinetics by changing the strength of the attracting fixed point for a particular demand.
The effect of law enforcement deployment patterns on motorists' speeds : final report.
DOT National Transportation Integrated Search
2003-12-01
The combination of increased demands on Oregons transportation system and limited law enforcement resources has led the Oregon Department of Transportation (ODOT) to investigate whether a relationship exists between motorists speeds and law enf...
Intelligent transportation systems benefits and costs : 2003 update
DOT National Transportation Integrated Search
2003-03-01
The increasing demand for travel by highway and public transit in the United States is causing the transportation system to reach the limits of its existing capacity. Intelligent Transportation Systems (ITS) can help ease this strain through the appl...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Meador, Richard J.; Hatley, Darrel D.
2004-06-01
PNNL DSOM technology coordinates efficient steam plant operation with EMCS and SCADA systems, providing generation support and automated load shedding to meet peak demand limits saving over $1M in two years.
Hearne, Luke J; Cocchi, Luca; Zalesky, Andrew; Mattingley, Jason B
2017-08-30
Our capacity for higher cognitive reasoning has a measurable limit. This limit is thought to arise from the brain's capacity to flexibly reconfigure interactions between spatially distributed networks. Recent work, however, has suggested that reconfigurations of task-related networks are modest when compared with intrinsic "resting-state" network architecture. Here we combined resting-state and task-driven functional magnetic resonance imaging to examine how flexible, task-specific reconfigurations associated with increasing reasoning demands are integrated within a stable intrinsic brain topology. Human participants (21 males and 28 females) underwent an initial resting-state scan, followed by a cognitive reasoning task involving different levels of complexity, followed by a second resting-state scan. The reasoning task required participants to deduce the identity of a missing element in a 4 × 4 matrix, and item difficulty was scaled parametrically as determined by relational complexity theory. Analyses revealed that external task engagement was characterized by a significant change in functional brain modules. Specifically, resting-state and null-task demand conditions were associated with more segregated brain-network topology, whereas increases in reasoning complexity resulted in merging of resting-state modules. Further increments in task complexity did not change the established modular architecture, but affected selective patterns of connectivity between frontoparietal, subcortical, cingulo-opercular, and default-mode networks. Larger increases in network efficiency within the newly established task modules were associated with higher reasoning accuracy. Our results shed light on the network architectures that underlie external task engagement, and highlight selective changes in brain connectivity supporting increases in task complexity. SIGNIFICANCE STATEMENT Humans have clear limits in their ability to solve complex reasoning problems. It is thought that such limitations arise from flexible, moment-to-moment reconfigurations of functional brain networks. It is less clear how such task-driven adaptive changes in connectivity relate to stable, intrinsic networks of the brain and behavioral performance. We found that increased reasoning demands rely on selective patterns of connectivity within cortical networks that emerged in addition to a more general, task-induced modular architecture. This task-driven architecture reverted to a more segregated resting-state architecture both immediately before and after the task. These findings reveal how flexibility in human brain networks is integral to achieving successful reasoning performance across different levels of cognitive demand. Copyright © 2017 the authors 0270-6474/17/378399-13$15.00/0.
The Influence of Load and Speed on Individuals' Movement Behavior.
Frost, David M; Beach, Tyson A C; Callaghan, Jack P; McGill, Stuart M
2015-09-01
Because individuals' movement patterns have been linked to their risk of future injury, movement evaluations have become a topic of interest. However, if individuals adapt their movement behavior in response to the demands of a task, the utility of evaluations comprising only low-demand activities could have limited application with regard to the prediction of future injury. This investigation examined the impact of load and speed on individuals' movement behavior. Fifty-two firefighters performed 5 low-demand (i.e., light load, low movement speed) whole-body tasks (i.e., lift, squat, lunge, push, and pull). Each task was then modified by increasing the speed, external load, or speed and load. Select measures of motion were used to characterize the performance of each task, and comparisons were made between conditions. The participants adapted their movement behavior in response to the external demands of a task (64 and 70% of all the variables were influenced [p ≤ 0.05] by changing the load and speed, respectively), but in a manner unique to the task and type of demand. The participants exhibited greater spine and frontal plane knee motion in response to an increase in speed when compared with increasing loads. However, there were a large number of movement strategies exhibited by individual firefighters that differed from the group's response. The data obtained here imply that individuals may not be physically prepared to perform safely or effectively when a task's demands are elevated simply because they exhibit the ability to perform a low-demand activity with competence. Therefore, movement screens comprising only low-demand activities may not adequately reflect an individual's capacity, or their risk of injury, and could adversely affect any recommendations that are made for training or job performance.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Marks, Gary; Wilcox, Edmund; Olsen, Daniel
California agricultural irrigation consumes more than ten billion kilowatt hours of electricity annually and has significant potential for contributing to a reduction of stress on the grid through demand response, permanent load shifting, and energy efficiency measures. To understand this potential, a scoping study was initiated for the purpose of determining the associated opportunities, potential, and adoption challenges in California agricultural irrigation. The primary research for this study was conducted in two ways. First, data was gathered and parsed from published sources that shed light on where the best opportunities for load shifting and demand response lie within the agriculturalmore » irrigation sector. Secondly, a small limited survey was conducted as informal face-to-face interviews with several different California growers to get an idea of their ability and willingness to participate in permanent load shifting and/or demand response programs. Analysis of the data obtained from published sources and the survey reveal demand response and permanent load shifting opportunities by growing region, irrigation source, irrigation method, grower size, and utility coverage. The study examines some solutions for demand response and permanent load shifting in agricultural irrigation, which include adequate irrigation system capacity, automatic controls, variable frequency drives, and the contribution from energy efficiency measures. The study further examines the potential and challenges for grower acceptance of demand response and permanent load shifting in California agricultural irrigation. As part of the examination, the study considers to what extent permanent load shifting, which is already somewhat accepted within the agricultural sector, mitigates the need or benefit of demand response for agricultural irrigation. Recommendations for further study include studies on how to gain grower acceptance of demand response as well as other related studies such as conducting a more comprehensive survey of California growers.« less
Visualizing Alternative Phosphorus Scenarios for Future Food Security
Neset, Tina-Simone; Cordell, Dana; Mohr, Steve; VanRiper, Froggi; White, Stuart
2016-01-01
The impact of global phosphorus scarcity on food security has increasingly been the focus of scientific studies over the past decade. However, systematic analyses of alternative futures for phosphorus supply and demand throughout the food system are still rare and provide limited inclusion of key stakeholders. Addressing global phosphorus scarcity requires an integrated approach exploring potential demand reduction as well as recycling opportunities. This implies recovering phosphorus from multiple sources, such as food waste, manure, and excreta, as well as exploring novel opportunities to reduce the long-term demand for phosphorus in food production such as changing diets. Presently, there is a lack of stakeholder and scientific consensus around priority measures. To therefore enable exploration of multiple pathways and facilitate a stakeholder dialog on the technical, behavioral, and institutional changes required to meet long-term future phosphorus demand, this paper introduces an interactive web-based tool, designed for visualizing global phosphorus scenarios in real time. The interactive global phosphorus scenario tool builds on several demand and supply side measures that can be selected and manipulated interactively by the user. It provides a platform to facilitate stakeholder dialog to plan for a soft landing and identify a suite of concrete priority options, such as investing in agricultural phosphorus use efficiency, or renewable fertilizers derived from phosphorus recovered from wastewater and food waste, to determine how phosphorus demand to meet future food security could be attained on a global scale in 2040 and 2070. This paper presents four example scenarios, including (1) the potential of full recovery of human excreta, (2) the challenge of a potential increase in non-food phosphorus demand, (3) the potential of decreased animal product consumption, and (4) the potential decrease in phosphorus demand from increased efficiency and yield gains in crop and livestock systems. PMID:27840814
Visualizing Alternative Phosphorus Scenarios for Future Food Security.
Neset, Tina-Simone; Cordell, Dana; Mohr, Steve; VanRiper, Froggi; White, Stuart
2016-01-01
The impact of global phosphorus scarcity on food security has increasingly been the focus of scientific studies over the past decade. However, systematic analyses of alternative futures for phosphorus supply and demand throughout the food system are still rare and provide limited inclusion of key stakeholders. Addressing global phosphorus scarcity requires an integrated approach exploring potential demand reduction as well as recycling opportunities. This implies recovering phosphorus from multiple sources, such as food waste, manure, and excreta, as well as exploring novel opportunities to reduce the long-term demand for phosphorus in food production such as changing diets. Presently, there is a lack of stakeholder and scientific consensus around priority measures. To therefore enable exploration of multiple pathways and facilitate a stakeholder dialog on the technical, behavioral, and institutional changes required to meet long-term future phosphorus demand, this paper introduces an interactive web-based tool, designed for visualizing global phosphorus scenarios in real time. The interactive global phosphorus scenario tool builds on several demand and supply side measures that can be selected and manipulated interactively by the user. It provides a platform to facilitate stakeholder dialog to plan for a soft landing and identify a suite of concrete priority options, such as investing in agricultural phosphorus use efficiency, or renewable fertilizers derived from phosphorus recovered from wastewater and food waste, to determine how phosphorus demand to meet future food security could be attained on a global scale in 2040 and 2070. This paper presents four example scenarios, including (1) the potential of full recovery of human excreta, (2) the challenge of a potential increase in non-food phosphorus demand, (3) the potential of decreased animal product consumption, and (4) the potential decrease in phosphorus demand from increased efficiency and yield gains in crop and livestock systems.
Refrigerated Warehouse Demand Response Strategy Guide
DOE Office of Scientific and Technical Information (OSTI.GOV)
Scott, Doug; Castillo, Rafael; Larson, Kyle
This guide summarizes demand response measures that can be implemented in refrigerated warehouses. In an appendix, it also addresses related energy efficiency opportunities. Reducing overall grid demand during peak periods and energy consumption has benefits for facility operators, grid operators, utility companies, and society. State wide demand response potential for the refrigerated warehouse sector in California is estimated to be over 22.1 Megawatts. Two categories of demand response strategies are described in this guide: load shifting and load shedding. Load shifting can be accomplished via pre-cooling, capacity limiting, and battery charger load management. Load shedding can be achieved by lightingmore » reduction, demand defrost and defrost termination, infiltration reduction, and shutting down miscellaneous equipment. Estimation of the costs and benefits of demand response participation yields simple payback periods of 2-4 years. To improve demand response performance, it’s suggested to install air curtains and another form of infiltration barrier, such as a rollup door, for the passageways. Further modifications to increase efficiency of the refrigeration unit are also analyzed. A larger condenser can maintain the minimum saturated condensing temperature (SCT) for more hours of the day. Lowering the SCT reduces the compressor lift, which results in an overall increase in refrigeration system capacity and energy efficiency. Another way of saving energy in refrigerated warehouses is eliminating the use of under-floor resistance heaters. A more energy efficient alternative to resistance heaters is to utilize the heat that is being rejected from the condenser through a heat exchanger. These energy efficiency measures improve efficiency either by reducing the required electric energy input for the refrigeration system, by helping to curtail the refrigeration load on the system, or by reducing both the load and required energy input.« less
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.
Sorel, Mark H.; Hansen, Adam G.; Connelly, Kristin A.; Beauchamp, David A.
2016-01-01
The reintroduction of anadromous salmonids in reservoirs is being proposed with increasing frequency, requiring baseline studies to evaluate feasibility and estimate the capacity of reservoir food webs to support reintroduced populations. Using three reservoirs on the north fork Lewis River as a case study, we demonstrate a method to determine juvenile salmonid smolt rearing capacities for lakes and reservoirs. To determine if the Lewis River reservoirs can support reintroduced populations of juvenile stream-type Chinook Salmon Oncorhynchus tshawytscha, we evaluated the monthly production of daphniaDaphnia spp. (the primary zooplankton consumed by resident salmonids in the system) and used bioenergetics to model the consumption demand of resident fishes in each reservoir. To estimate the surplus of Daphnia prey available for reintroduced salmonids, we assumed a maximum sustainable exploitation rate and accounted for the consumption demand of resident fishes. The number of smolts that could have been supported was estimated by dividing any surplus Daphnia production by the simulated consumption demand of an individual Chinook Salmon fry rearing in the reservoir to successful smolt size. In all three reservoirs, densities of Daphnia were highest in the epilimnion, but warm epilimnetic temperatures and the vertical distribution of planktivores suggested that access to abundant epilimnetic prey was limited. By comparing accessible prey supply and demand on a monthly basis, we were able to identify potential prey supply bottlenecks that could limit smolt production and growth. These results demonstrate that a bioenergetics approach can be a valuable method of examining constraints on lake and reservoir rearing capacity, such as thermal structure and temporal food supply. This method enables numerical estimation of rearing capacity, which is a useful metric for managers evaluating the feasibility of reintroducing Pacific salmon Oncorhynchus spp. in lentic systems.
Englert, Chris
2017-08-01
Athletes are constantly confronted with self-control demands, but previous research has delivered sound empirical evidence that athletes are not always capable of dealing with these demands. According to the strength model of self-control, individuals have a limited amount of self-control strength, which can become temporarily depleted following self-control demands (e.g., attention regulation). When self-control strength is depleted, that is, in a state of ego depletion, athletes are less persistent during strenuous physical exercise, are less likely to follow their exercise regimens, and tend to perform worse under pressure. The aim of this review article is to highlight the importance of ego depletion in the field of sports and exercise and to discuss the recent research and controversies surrounding it. Copyright © 2017 Elsevier Ltd. All rights reserved.
Defrost Temperature Termination in Supermarket Refrigeration Systems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fricke, Brian A; Sharma, Vishaldeep
2011-11-01
The objective of this project was to determine the potential energy savings associated with implementing demand defrost strategies to defrost supermarket refrigerated display case evaporators, as compared to the widely accepted current practice of controlling display case defrost cycles with a preset timer. The defrost heater energy use of several representative display case types was evaluated. In addition, demand defrost strategies for refrigerated display cases as well as those used in residential refrigerator/freezers were evaluated. Furthermore, it is anticipated that future work will include identifying a preferred defrost strategy, with input from Retail Energy Alliance members. Based on this strategy,more » a demand defrost system will be designed which is suitable for supermarket refrigerated display cases. Limited field testing of the preferred defrost strategy will be performed in a supermarket environment.« less
Encapsulating urban traffic rhythms into road networks.
Wang, Junjie; Wei, Dong; He, Kun; Gong, Hang; Wang, Pu
2014-02-20
Using road GIS (geographical information systems) data and travel demand data for two U.S. urban areas, the dynamical driver sources of each road segment were located. A method to target road clusters closely related to urban traffic congestion was then developed to improve road network efficiency. The targeted road clusters show different spatial distributions at different times of a day, indicating that our method can encapsulate dynamical travel demand information into the road networks. As a proof of concept, when we lowered the speed limit or increased the capacity of road segments in the targeted road clusters, we found that both the number of congested roads and extra travel time were effectively reduced. In addition, the proposed modeling framework provided new insights on the optimization of transport efficiency in any infrastructure network with a specific supply and demand distribution.
Encapsulating Urban Traffic Rhythms into Road Networks
Wang, Junjie; Wei, Dong; He, Kun; Gong, Hang; Wang, Pu
2014-01-01
Using road GIS (geographical information systems) data and travel demand data for two U.S. urban areas, the dynamical driver sources of each road segment were located. A method to target road clusters closely related to urban traffic congestion was then developed to improve road network efficiency. The targeted road clusters show different spatial distributions at different times of a day, indicating that our method can encapsulate dynamical travel demand information into the road networks. As a proof of concept, when we lowered the speed limit or increased the capacity of road segments in the targeted road clusters, we found that both the number of congested roads and extra travel time were effectively reduced. In addition, the proposed modeling framework provided new insights on the optimization of transport efficiency in any infrastructure network with a specific supply and demand distribution. PMID:24553203
Richa, N; Zreik, H; Richa, S
2016-04-01
The aim of our study was to investigate the influence of demographic factors (gender and age), work related factors (the position and years of practice) and psychosocial risk factors (cognitive demands, demands to hide emotions, work-family conflict, offensive behaviors…) on the development of burnout among flight attendants, and the nature of psychosocial factors to which they are exposed. The sample was divided into two groups: 67 flight attendants and 67 persons in various jobs. Our sampling units were informed and consented to fill in two questionnaires: the Copenhagen burnout inventory (CBI) and the Copenhagen Psychosocial Questionnaire (COPSOQ II). The burnout syndrome affected both groups equally. It affected equally the women as well as men, whatever their age categories and their years of experience. The flight attendants occupying an intermediate position in the hierarchy had the highest score on the burnout syndrome. The psychosocial factors significantly found in flight attendants compared to the control group were: demands for hiding emotions, quantitative demands, emotional demands, temporal demands, lack of influence at work, of rewards, of possibility for development and variation of work, poor quality of leadership, exposure to sexual harassment, lack of social support from supervisors, colleagues, social community at work and work-family conflict. Four of them correlated positively with the development of burnout: quantitative demands, temporal demands, emotional demands and work-family conflict. Their expected work volume is very high (quantitative demands). They have to perform their tasks quickly in a limited time without forgetting the technical constraints (temporal demands). They have to work with an average of three hundred passengers besides colleagues and subordinates, which requires diligent control of the emotions promoted by the airline code of conduct based on repression of emotions (emotional demands). These demands affect the workers once they find themselves in their family environment and can have a negative effect on their private life (work-family conflict). However, the predictability seems to allow them to be aware of decisions and changes and protect them against burnout. The profession of flight attendants appears to be characterized by some psychosocial risk factors, some of which are positively correlated with burnout. Improved working conditions can prevent these risks and protect these employees from burnout. Copyright © 2015 L’Encéphale, Paris. Published by Elsevier Masson SAS. All rights reserved.
Barriers to Household Risk Management: Evidence from India.
Cole, Shawn; Giné, Xavier; Tobacman, Jeremy; Townsend, Robert; Topalova, Petia; Vickery, James
2013-01-01
Why do many households remain exposed to large exogenous sources of non-systematic income risk? We use a series of randomized field experiments in rural India to test the importance of price and non-price factors in the adoption of an innovative rainfall insurance product. Demand is significantly price sensitive, but widespread take-up would not be achieved even if the product offered a payout ratio comparable to U.S. insurance contracts. We present evidence suggesting that lack of trust, liquidity constraints and limited salience are significant non-price frictions that constrain demand. We suggest contract design improvements to mitigate these frictions.
NASA Astrophysics Data System (ADS)
Ho, M. W.; Devineni, N.; Cook, E. R.; Lall, U.
2017-12-01
As populations and associated economic activity in the US evolve, regional demands for water likewise change. For regions dependent on surface water, dams and reservoirs are critical to storing and managing releases of water and regulating the temporal and spatial availability of water in order to meet these demands. Storage capacities typically range from seasonal storage in the east to multi-annual and decadal-scale storage in the drier west. However, most dams in the US were designed with limited knowledge regarding the range, frequency, and persistence of hydroclimatic extremes. Demands for water supplied by these dams have likewise changed. Furthermore, many dams in the US are now reaching or have already exceeded their economic design life. The converging issues of aging dams, improved knowledge of hydroclimatic variability, and evolving demands for dam services result in a pressing need to evaluate existing reservoir capacities with respect to contemporary water demands, long term hydroclimatic variability, and service reliability into the future. Such an effort is possible given the recent development of two datasets that respectively address hydroclimatic variability in the conterminous United States over the past 555 years and human water demand related water stress over the same region. The first data set is a paleoclimate reconstruction of streamflow variability across the CONUS region based on a tree-ring informed reconstruction of the Palmer Drought Severity Index. This streamflow reconstruction suggested that wet spells with shorter drier spells were a key feature of 20th century streamflow compared with the preceding 450 years. The second data set in an annual cumulative drought index that is a measure of water balance based on water supplied through precipitation and water demands based on evaporative demands, agricultural, urban, and industrial demands. This index identified urban and regional hotspots that were particularly dependent on water transfers and vulnerable to persistent drought risk. These data sets are used in conjunction with the national inventory of dams to assess the current capacity of dams to meet water demands considering variability in streamflow over the past 555 years. A case study in the North-East US is presented.
Letter from America: UK and US state-funded dental provision.
Currie, R B; Pretty, I A; Tickle, M; Maupomé, G
2012-12-01
Current UK and US economic conditions have re-focussed attention on the need to deliver dental care with limited finance and resources. This raises hard questions determining which services will be offered and what they should achieve to satisfy public demands and needs. We consider impending dental health reforms in the US and UK within the context of contemporary experiences to identify issues and delivery goals for the two nations. The paper provides a brief history and background of the development of social dental care models in the UK and US, highlighting some differences in state-funded delivery of dental care. SHIFTING DEMAND: From the 1950s, demand for dental treatment has increased and acquired a more complex composition growing from predominantly surgical and restorative treatment to encompass preventive care and cosmetic services. PRIORITISING CARE ACCORDING TO NEED: Despite improvements in general health and technology, inequalities in access and utilisation of dental care are still experienced, primarily by groups with low socio-economic status. DELIVERY: BALANCING RESOURCES, DEMAND AND NEED: In developing and delivering reform agendas, much can be learned from previous policy interventions. Pressures of cost, coverage, and capacity, besides demand versus need must be carefully considered and balanced to deliver quality service and value for users and taxpayers. Ethical and moral consideration should be given to making services needs-driven to address high treatment requirements rather than the high care demands of the worried well. This challenge brings the additional political pressure of convincing many of the voters (and subsequent complainers) that their demands may be less important than the needs of others.
Initial Development of a Brief Behavioral Economic Assessment of Alcohol Demand
Owens, Max M.; Murphy, Cara M.; MacKillop, James
2015-01-01
Due to difficulties with definition and measurement, the role of conscious craving in substance use disorders remains contentious. To address this, behavioral economics is increasingly being used to quantify aspects of an individual’s acute motivation to use a substance. Doing so typically involves the use of a purchase task, in which participants make choices about consuming alcohol or other substances at various prices and multiple indices of alcohol demand are generated. However, purchase tasks can be limited by the time required to administer and score them. In the current study, a brief 3-item measure, designed to capture three important indices of demand that are derived from demand curve modeling (intensity, Omax, and breakpoint), was investigated in a group of 84 heavy drinkers. Participants underwent a cue-reactivity paradigm that is established to increase both conscious craving and alcohol demand on traditional purchase tasks. All three indices of demand for alcohol measured using the abbreviated measure increased significantly in response to alcohol cues, analogous to what has been observed using a traditional purchase task. Additionally, the correlations between these indices and subjective craving were modest-to-moderate, as has been found in studies comparing craving to the indices derived from purchase tasks. These findings suggest that this abbreviated measure may be a useful and efficient way to capture important and distinct aspects of motivation for alcohol. If these results are confirmed, this measure may be able to help increase the portability of behavioral economic indices of demand into novel research and clinical contexts. PMID:27135038
Quantifying the link between crop production and mined groundwater irrigation in China.
Grogan, Danielle S; Zhang, Fan; Prusevich, Alexander; Lammers, Richard B; Wisser, Dominik; Glidden, Stanley; Li, Changsheng; Frolking, Steve
2015-04-01
In response to increasing demand for food, Chinese agriculture has both expanded and intensified over the past several decades. Irrigation has played a key role in increasing crop production, and groundwater is now an important source of irrigation water. Groundwater abstraction in excess of recharge (which we use here to estimate groundwater mining) has resulted in declining groundwater levels and could eventually restrict groundwater availability. In this study we used a hydrological model, WBMplus, in conjunction with a process based crop growth model, DNDC, to evaluate Chinese agriculture's recent dependence upon mined groundwater, and to quantify mined groundwater-dependent crop production across a domain that includes variation in climate, crop choice, and management practices. This methodology allowed for the direct attribution of crop production to irrigation water from rivers and reservoirs, shallow (renewable) groundwater, and mined groundwater. Simulating 20 years of weather variability and circa year 2000 crop areas, we found that mined groundwater fulfilled 20%-49% of gross irrigation water demand, assuming all demand was met. Mined groundwater accounted for 15%-27% of national total crop production. There was high spatial variability across China in irrigation water demand and crop production derived from mined groundwater. We find that climate variability and mined groundwater demand do not operate independently; rather, years in which irrigation water demand is high due to the relatively hot and dry climate also experience limited surface water supplies and therefore have less surface water with which to meet that high irrigation water demand. Copyright © 2014 Elsevier B.V. All rights reserved.
A New Technique for Compensating Joint Limits in a Robot Manipulator
NASA Technical Reports Server (NTRS)
Litt, Jonathan; Hickman, Andre; Guo, Ten-Huei
1996-01-01
A new robust, optimal, adaptive technique for compensating rate and position limits in the joints of a six degree-of-freedom elbow manipulator is presented. In this new algorithm, the unmet demand as a result of actuator saturation is redistributed among the remaining unsaturated joints. The scheme is used to compensate for inadequate path planning, problems such as joint limiting, joint freezing, or even obstacle avoidance, where a desired position and orientation are not attainable due to an unrealizable joint command. Once a joint encounters a limit, supplemental commands are sent to other joints to best track, according to a selected criterion, the desired trajectory.
Service contract of Renault Kerax 440 truck with deductible and policy limit coverage modification
NASA Astrophysics Data System (ADS)
Bustami, Pasaribu, Udjianna. S.; Husniah, Hennie
2016-02-01
In this paper we discuss a service contracts with coverage modification that only offer preventive maintenance and corrective maintenance for Renault Kerax 440 Truck by service contract provider. Corrective maintenance costs is modified with deductible and policy limit during the period of the service contract. Demand for a service contract is only influenced by the price of the service contract, deductible, and policy limit offered by producer to consumer. The main problem in this thesis is determining the price of a service contract, deductible, and policy limit to get maximum profit for producer for each of service contract.
DOT National Transportation Integrated Search
2016-01-01
Transportation decision makers have the difficult task of investment decision making having limited resources while : maximizing benefit to the transportation system. Given the growth in freight transport and its importance to national, : state, and ...
Fueling the future with fungal genomics
USDA-ARS?s Scientific Manuscript database
Rapidly growing human populations are escalating the demand for energy in our interdependent world. Limited fossil resources and negative ecological impacts of petroleum exploitation dictate the need to explore alternative energy sources. Cellulosic biofuels, the use of plant biomass to produce alco...
Signal Timing and Coordination Strategies Under Varying Traffic Demands
DOT National Transportation Integrated Search
2012-07-01
Current practice for signal timing and signal coordination is to develop and operate a limited number of predetermined time-of-day plans. Coordination plans are commonly developed for and based on weekday morning, mid-day, evening, and weekend peak p...
Candidate eco-friendly gas mixtures for MPGDs
NASA Astrophysics Data System (ADS)
Benussi, L.; Bianco, S.; Saviano, G.; Muhammad, S.; Piccolo, D.; Ferrini, M.; Parvis, M.; Grassini, S.; Colafranceschi, S.; Kjølbro, J.; Sharma, A.; Yang, D.; Chen, G.; Ban, Y.; Li, Q.
2018-02-01
Modern gas detectors for detection of particles require F-based gases for optimal performance. Recent regulations demand the use of environmentally unfriendly F-based gases to be limited or banned. This review studies properties of potential eco-friendly gas candidate replacements.
Visual demand of curves and fog-limited sight distance and its relationship to brake response time.
DOT National Transportation Integrated Search
2006-05-01
Driver distraction is a major contributing factor to automobile crashes. National Highway Traffic Safety Administration (NHTSA) has estimated that approximately 25% of crashes are attributed to driver distraction and inattention (Wang, Knipling, & Go...
NONPOTABLE WATER REUSE MANAGEMENT PRACTICES
Globally, the need for water reuse is increasing due to rising water demands and finite water resources. In addition, certain regulations and policies, such as zero discharge initiatives or limited new dam construction, may indirectly contribute to the need for reuse. With growin...
NONPOTABLE WATER REUSE MANAGEMENT PRACTICES
Globally, the need for water reuse is increasing due to rising water demands and finite water resources. In addition, certain regulations and policies, such as zero discharge initiatives or limited new dam construction, may indirectly contribute to the need for reuse. Also, with ...
Learning at Home: Public Library Service to Homeschoolers.
ERIC Educational Resources Information Center
Madden, Susan B.
1991-01-01
Offers definitions, statistics, and suggestions for public librarians working with homeschoolers. Library concerns are addressed, including censorship, negative staff attitudes, technology demands, and administrative limits; and ways to make homeschoolers more welcome are suggested, including compiling homeschooling resource materials, library…
2013-01-08
measure of sampling adequacy, the Kaiser - Meyer - Olkin (KMO) value ( Kaiser , 1970, 1974), was .76 for randomized group 1 (n = 114) and .72 for...Wefel, Lenzi, Theriault, Davis, & Meyers , 2004). Cognitive Challenges in the Context of Work Cognitive demands are required in many different types...Shilling et al., 2005; Wefel et al., 2004; Wefel, Saleeba, Buzdar, & Meyers , 2010). However, cognitive limitations observed and reported can depend on
NASA Astrophysics Data System (ADS)
Grubler, Arnulf; Wilson, Charlie; Bento, Nuno; Boza-Kiss, Benigna; Krey, Volker; McCollum, David L.; Rao, Narasimha D.; Riahi, Keywan; Rogelj, Joeri; De Stercke, Simon; Cullen, Jonathan; Frank, Stefan; Fricko, Oliver; Guo, Fei; Gidden, Matt; Havlík, Petr; Huppmann, Daniel; Kiesewetter, Gregor; Rafaj, Peter; Schoepp, Wolfgang; Valin, Hugo
2018-06-01
Scenarios that limit global warming to 1.5 °C describe major transformations in energy supply and ever-rising energy demand. Here, we provide a contrasting perspective by developing a narrative of future change based on observable trends that results in low energy demand. We describe and quantify changes in activity levels and energy intensity in the global North and global South for all major energy services. We project that global final energy demand by 2050 reduces to 245 EJ, around 40% lower than today, despite rises in population, income and activity. Using an integrated assessment modelling framework, we show how changes in the quantity and type of energy services drive structural change in intermediate and upstream supply sectors (energy and land use). Down-sizing the global energy system dramatically improves the feasibility of a low-carbon supply-side transformation. Our scenario meets the 1.5 °C climate target as well as many sustainable development goals, without relying on negative emission technologies.
Kampa, Judith; Rigotti, Thomas; Otto, Kathleen
2017-04-07
In order to gain more knowledge on how the positive leadership concept of authentic leadership impacts follower strain, this study tries to uncover procedural justice as an underlying mechanism. In contrast to previous work, we exclusively base our theoretical model on justice theories. Specifically, we hypothesize that authentic leadership negatively predicts emotional exhaustion through perceptions of procedural justice. We assume that this indirect effect is conditional on followers' amount of emotional demands, and that the procedural justice-emotional exhaustion relationship is stronger when emotional demands are high. This finally results in a stronger exhaustion-reducing effect of authentic leadership. The proposed moderated mediation model was tested in a sample of N=628 employees nested in 168 teams using lagged data from three waves. Results provide support for all hypotheses. Authentic leadership is critical to employees' well-being as it contributes to an elevated perception of positive work conditions (procedural justice), especially in contexts with high emotional demands. Limitations and practical implications on leadership development are discussed.
KAMPA, Judith; RIGOTTI, Thomas; OTTO, Kathleen
2016-01-01
In order to gain more knowledge on how the positive leadership concept of authentic leadership impacts follower strain, this study tries to uncover procedural justice as an underlying mechanism. In contrast to previous work, we exclusively base our theoretical model on justice theories. Specifically, we hypothesize that authentic leadership negatively predicts emotional exhaustion through perceptions of procedural justice. We assume that this indirect effect is conditional on followers’ amount of emotional demands, and that the procedural justice-emotional exhaustion relationship is stronger when emotional demands are high. This finally results in a stronger exhaustion-reducing effect of authentic leadership. The proposed moderated mediation model was tested in a sample of N=628 employees nested in 168 teams using lagged data from three waves. Results provide support for all hypotheses. Authentic leadership is critical to employees’ well-being as it contributes to an elevated perception of positive work conditions (procedural justice), especially in contexts with high emotional demands. Limitations and practical implications on leadership development are discussed. PMID:27818452
2017-01-01
Background Voluntary medical male circumcision is an integral part of the South African government’s response to the HIV and AIDS epidemic. However, there remains a limited body of economic analysis on the cost of VMMC programming, and the demand creation activities used to mobilize males, especially among adolescent boys in school. This study addresses this gap by presenting the costs of a VMMC program which adopted two demand creation strategies targeting school-going males in South Africa. Methods Cost data was collected from a VMMC program in the KwaZulu-Natal province of South Africa. A retrospective, micro-costing ingredient approach was applied to identify, measure and value resources of two demand creation strategies targeting young males. Results The program circumcised 4987 young males between May 2011 and February 2013, at a cost of $127.68 per circumcision. Demand creation activities accounted for 32% of the total cost, HCT contributing 10% with the medical circumcision procedure accounting for 58% of the total cost. Using the first demand creation strategy, 2168 circumcisions were performed at a cost of $149.57 per circumcision. Following this first strategy, a second demand creation strategy was adopted which saw the cost fall to $110.85 per circumcision. More young males were recruited following the second strategy with clinic services more efficiently utilized. Whilst the cost per circumcision of demand activities rose slightly between the first ($39.94) and second ($41.65) strategy, there was a substantial reduction in the cost of the circumcision procedure; $90.01 under the first strategy falling to $60.60 following the adoption of the second demand creation strategy. Conclusion Ensuring the optimal use of clinic facilities was the primary driver in reducing the cost per circumcision. This VMMC program has illustrated the value of evaluating progress and instituting changes to attain better cost efficiencies. This adjustment resulted in a substantial reduction in the cost per circumcision. PMID:28632768
George, Gavin; Strauss, Michael; Asfaw, Elias
2017-01-01
Voluntary medical male circumcision is an integral part of the South African government's response to the HIV and AIDS epidemic. However, there remains a limited body of economic analysis on the cost of VMMC programming, and the demand creation activities used to mobilize males, especially among adolescent boys in school. This study addresses this gap by presenting the costs of a VMMC program which adopted two demand creation strategies targeting school-going males in South Africa. Cost data was collected from a VMMC program in the KwaZulu-Natal province of South Africa. A retrospective, micro-costing ingredient approach was applied to identify, measure and value resources of two demand creation strategies targeting young males. The program circumcised 4987 young males between May 2011 and February 2013, at a cost of $127.68 per circumcision. Demand creation activities accounted for 32% of the total cost, HCT contributing 10% with the medical circumcision procedure accounting for 58% of the total cost. Using the first demand creation strategy, 2168 circumcisions were performed at a cost of $149.57 per circumcision. Following this first strategy, a second demand creation strategy was adopted which saw the cost fall to $110.85 per circumcision. More young males were recruited following the second strategy with clinic services more efficiently utilized. Whilst the cost per circumcision of demand activities rose slightly between the first ($39.94) and second ($41.65) strategy, there was a substantial reduction in the cost of the circumcision procedure; $90.01 under the first strategy falling to $60.60 following the adoption of the second demand creation strategy. Ensuring the optimal use of clinic facilities was the primary driver in reducing the cost per circumcision. This VMMC program has illustrated the value of evaluating progress and instituting changes to attain better cost efficiencies. This adjustment resulted in a substantial reduction in the cost per circumcision.
Work limitations, workplace concerns, and job satisfaction of persons with chronic disease.
Siu, Andrew M H; Hung, Anchor; Lam, Ada Y L; Cheng, Andy
2013-01-01
This study investigates the workplace experiences of people with chronic diseases, including their work limitations, emotional health, concerns about discrimination, and support from colleagues and employer. This study identifies the factors that contribute to work adjustment (job tenure and job satisfaction). A purposive sample of 136 persons aged 18 to 60 with chronic diseases who had been employed in the past 6 months completed a survey about their workplace experience. The questionnaire included several standardized instruments: the Perceived Health and Self-efficacy in Managing Chronic Disease Scale, Work Limitations Questionnaire, Overall Job Satisfaction Scale, and the Depression Anxiety Stress Scale-21. The researchers also designed original items to measure concerns about discriminatory practices, workplace support, and self-stigma. Persons with chronic diseases were fairly satisfied with their jobs and had extended stays in those jobs. They reported a minor productivity loss and physical limitations. Most participants let co-workers, employers, and supervisors know they had chronic disease, but they were concerned about the support those people provide. Participants were more likely to be highly satisfied with their jobs if they had high self-efficacy in managing their disease, perceived more workplace support, and had less work limitations (especially output demands). Job tenure is associated age, education, and monthly income, but not clinical indicators. Persons with chronic disease who were able to maintain good work adjustment tended to be "fit" with few work limitations and little emotional distress. The key factors affecting work adjustment were efficacy in managing their disease, workplace support, and output demands.
Demands of eicosapentaenoic acid (EPA) in Daphnia: are they dependent on body size?
Sikora, Anna B; Petzoldt, Thomas; Dawidowicz, Piotr; von Elert, Eric
2016-10-01
Fatty acids contribute to the nutritional quality of the phytoplankton and, thus, play an important role in Daphnia nutrition. One of the polyunsaturated fatty acids (PUFAs)--eicosapentaenoic acid (EPA)--has been shown to predict carbon transfer between primary producers and consumers in lakes, suggesting that EPA limitation of Daphnia in nature is widespread. Although the demand for EPA must be covered by the diet, the demand of EPA in Daphnia that differ in body size has not been addressed yet. Here, we hypothesize that the demand for EPA in Daphnia is size-dependent and that bigger species have a higher EPA demand. To elucidate this, a growth experiment was conducted in which at 20 °C three Daphnia taxa (small-sized D. longispina complex, medium-sized D. pulicaria, and large-bodied D. magna) were fed Synechococcus elongatus supplemented with cholesterol and increasing concentrations of EPA. In addition, fatty acid analyses of Daphnia were performed. Our results show that the saturation threshold for EPA-dependent growth increased with increasing body size. This increase in thresholds with body size may provide another mechanism contributing to the prevalence of small-bodied cladocera in warm habitats and to the midsummer decline of large cladocera in eutrophic water bodies.
Elmusharaf, Khalifa; Byrne, Elaine; O'Donovan, Diarmuid
2015-09-08
Universal health access will not be achieved unless women are cared for in their own communities and are empowered to take decisions about their own health in a supportive environment. This will only be achieved by community-based demand side interventions for maternal health access. In this review article, we highlight three common strategies to increase demand-side barriers to maternal healthcare access and identify the main challenges that still need to be addressed for these strategies to be effective. Common demand side strategies can be grouped into three categories:(i) Financial incentives/subsidies; (ii) Enhancing patient transfer, and; (iii) Community involvement. The main challenges in assessing the effectiveness or efficacy of these interventions or strategies are the lack of quality evidence on their outcome and impact and interventions not integrated into existing health or community systems. However, what is highlighted in this review and overlooked in most of the published literature on this topic is the lack of knowledge about the context in which these strategies are to be implemented. We suggest three challenges that need to be addressed to create a supportive environment in which these demand-side strategies can effectively improve access to maternal health services. These include: addressing decision-making norms, engaging in intergenerational dialogue, and designing contextually appropriate communication strategies.
Exploring demand reduction through design, durability and 'usership' of fashion clothes.
Fletcher, Kate
2017-06-13
Global planetary boundaries confer limits to production and consumption of material goods. They also confer an obligation to experiment, as individuals and collectively as society, with less-materially-intensive, but no less exuberant, ways of living. This paper takes up this mantle and explores materials demand reduction through a focus on design, fashion garments and the universal, everyday activity of wearing clothes. It takes as its starting point the design of longer-lasting products, a widely favoured strategy for increasing materials efficiency and reducing materials demand in many sectors, including fashion. Drawing on scholarship in the field of design for sustainability and ethnographic research conducted in 16 locations in nine countries about already-existing practices of intensive use and maintenance of clothing, this paper critiques the effectiveness of durability strategies to reduce the amount of materials used. It argues for an update in the familiar preference within sustainability debates for the 'techno-fix' to explore instead resourceful use of materials as emerging from human actions and relationships with material goods. It suggests that, while facilitated by design, technology and engineering, opportunities to reduce materials demand begin in individual and collective practices, which, in turn, have dynamic implications for use of materials.This article is part of the themed issue 'Material demand reduction'. © 2017 The Author(s).
DOE Office of Scientific and Technical Information (OSTI.GOV)
Thompson, Lisa; Lekov, Alex; McKane, Aimee
2010-08-20
This case study enhances the understanding of open automated demand response opportunities in municipal wastewater treatment facilities. The report summarizes the findings of a 100 day submetering project at the San Luis Rey Wastewater Treatment Plant, a municipal wastewater treatment facility in Oceanside, California. The report reveals that key energy-intensive equipment such as pumps and centrifuges can be targeted for large load reductions. Demand response tests on the effluent pumps resulted a 300 kW load reduction and tests on centrifuges resulted in a 40 kW load reduction. Although tests on the facility?s blowers resulted in peak period load reductions ofmore » 78 kW sharp, short-lived increases in the turbidity of the wastewater effluent were experienced within 24 hours of the test. The results of these tests, which were conducted on blowers without variable speed drive capability, would not be acceptable and warrant further study. This study finds that wastewater treatment facilities have significant open automated demand response potential. However, limiting factors to implementing demand response are the reaction of effluent turbidity to reduced aeration load, along with the cogeneration capabilities of municipal facilities, including existing power purchase agreements and utility receptiveness to purchasing electricity from cogeneration facilities.« less
Global Human Appropriation of Net Primary Production and Associated Resource Decoupling: 2010-2050.
Zhou, Chuanbin; Elshkaki, Ayman; Graedel, T E
2018-02-06
Human appropriation of net primary production (HANPP) methodology has previously been developed to assess the intensity of anthropogenic extraction of biomass resources. However, there is limited analysis concerning future trends of HANPP. Here we present four scenarios for global biomass demand and HANPP harv (the most key component of HANPP) from 2010 to 2050 by incorporating data on expanded historical drivers and disaggregated biomass demand (food, wood material, and fuelwood). The results show that the biomass demand has the lowest value in the equitability world scenario (an egalitarian vision) and the highest value in the security foremost scenario (an isolationist vision). The biomass demand for food and materials increases over time, while fuelwood demand decreases over time. Global HANPP harv rises to between 8.5 and 10.1 Pg C/yr in 2050 in the four scenarios, 14-35% above its value in 2010, and some 50% of HANPP harv is calculated to be crop residues, wood residues, and food losses in the future. HANPP harv in developing regions (Asia, Africa, and Latin America) increases faster than that in more-developed regions (North America and Europe), due to urbanization, population growth, and increasing income. Decoupling of HANPP harv and socioeconomic development is also discussed in this work.
NASA Astrophysics Data System (ADS)
Zhang, Hao; Chen, Minghua; Parekh, Abhay; Ramchandran, Kannan
2011-09-01
We design a distributed multi-channel P2P Video-on-Demand (VoD) system using "plug-and-play" helpers. Helpers are heterogenous "micro-servers" with limited storage, bandwidth and number of users they can serve simultaneously. Our proposed system has the following salient features: (1) it jointly optimizes over helper-user connection topology, video storage distribution and transmission bandwidth allocation; (2) it minimizes server load, and is adaptable to varying supply and demand patterns across multiple video channels irrespective of video popularity; and (3) it is fully distributed and requires little or no maintenance overhead. The combinatorial nature of the problem and the system demand for distributed algorithms makes the problem uniquely challenging. By utilizing Lagrangian decomposition and Markov chain approximation based arguments, we address this challenge by designing two distributed algorithms running in tandem: a primal-dual storage and bandwidth allocation algorithm and a "soft-worst-neighbor-choking" topology-building algorithm. Our scheme provably converges to a near-optimal solution, and is easy to implement in practice. Packet-level simulation results show that the proposed scheme achieves minimum sever load under highly heterogeneous combinations of supply and demand patterns, and is robust to system dynamics of user/helper churn, user/helper asynchrony, and random delays in the network.
Exploring demand reduction through design, durability and ‘usership’ of fashion clothes
2017-01-01
Global planetary boundaries confer limits to production and consumption of material goods. They also confer an obligation to experiment, as individuals and collectively as society, with less-materially-intensive, but no less exuberant, ways of living. This paper takes up this mantle and explores materials demand reduction through a focus on design, fashion garments and the universal, everyday activity of wearing clothes. It takes as its starting point the design of longer-lasting products, a widely favoured strategy for increasing materials efficiency and reducing materials demand in many sectors, including fashion. Drawing on scholarship in the field of design for sustainability and ethnographic research conducted in 16 locations in nine countries about already-existing practices of intensive use and maintenance of clothing, this paper critiques the effectiveness of durability strategies to reduce the amount of materials used. It argues for an update in the familiar preference within sustainability debates for the ‘techno-fix’ to explore instead resourceful use of materials as emerging from human actions and relationships with material goods. It suggests that, while facilitated by design, technology and engineering, opportunities to reduce materials demand begin in individual and collective practices, which, in turn, have dynamic implications for use of materials. This article is part of the themed issue ‘Material demand reduction’. PMID:28461430
Verberk, W C E P; Sommer, U; Davidson, R L; Viant, M R
2013-10-01
Thermal limits in ectotherms may arise through a mismatch between supply and demand of oxygen. At higher temperatures, the ability of their cardiac and ventilatory activities to supply oxygen becomes insufficient to meet their elevated oxygen demand. Consequently, higher levels of oxygen in the environment are predicted to enhance tolerance of heat, whereas reductions in oxygen are expected to reduce thermal limits. Here, we extend previous research on thermal limits and oxygen limitation in aquatic insect larvae and directly test the hypothesis of increased anaerobic metabolism and lower energy status at thermal extremes. We quantified metabolite profiles in stonefly nymphs under varying temperatures and oxygen levels. Under normoxia, the concept of oxygen limitation applies to the insects studied. Shifts in the metabolome of heat-stressed stonefly nymphs clearly indicate the onset of anaerobic metabolism (e.g., accumulation of lactate, acetate, and alanine), a perturbation of the tricarboxylic acid cycle (e.g., accumulation of succinate and malate), and a decrease in energy status (e.g., ATP), with corresponding decreases in their ability to survive heat stress. These shifts were more pronounced under hypoxic conditions, and negated by hyperoxia, which also improved heat tolerance. Perturbations of metabolic pathways in response to either heat stress or hypoxia were found to be somewhat similar but not identical. Under hypoxia, energy status was greatly compromised at thermal extremes, but energy shortage and anaerobic metabolism could not be conclusively identified as the sole cause underlying thermal limits under hyperoxia. Metabolomics proved useful for suggesting a range of possible mechanisms to explore in future investigations, such as the involvement of leaking membranes or free radicals. In doing so, metabolomics provided a more complete picture of changes in metabolism under hypoxia and heat stress.
Limits to sulfur accumulation in transgenic lupin seeds expressing a foreign sulfur-rich protein.
Tabe, Linda M; Droux, Michel
2002-03-01
The low sulfur amino acid content of legume seeds restricts their nutritive value for animals. We have investigated the limitations to the accumulation of sulfur amino acids in the storage proteins of narrow leaf lupin (Lupinus angustifolius) seeds. Variation in sulfur supply to lupin plants affected the sulfur amino acid accumulation in the mature seed. However, when sulfur was in abundant supply, it accumulated to a large extent in oxidized form, rather than reduced form, in the seeds. At all but severely limiting sulfur supply, addition of a transgenic (Tg) sink for organic sulfur resulted in an increase in seed sulfur amino acid content. We hypothesize that demand, or sink strength for organic sulfur, which is itself responsive to environmental sulfur supply, was the first limit to the methionine (Met) and cysteine (Cys) content of wild-type lupin seed protein under most growing conditions. In Tg, soil-grown seeds expressing a foreign Met- and Cys-rich protein, decreased pools of free Met, free Cys, and glutathione indicated that the rate of synthesis of sulfur amino acids in the cotyledon had become limiting. Homeostatic mechanisms similar to those mediating the responses of plants to environmental sulfur stress resulted in an adjustment of endogenous protein composition in Tg seeds, even when grown at adequate sulfur supply. Uptake of sulfur by lupin cotyledons, as indicated by total seed sulfur at maturity, responded positively to increased sulfur supply, but not to increased demand in the Tg seeds.
Limits to Sulfur Accumulation in Transgenic Lupin Seeds Expressing a Foreign Sulfur-Rich Protein
Tabe, Linda M.; Droux, Michel
2002-01-01
The low sulfur amino acid content of legume seeds restricts their nutritive value for animals. We have investigated the limitations to the accumulation of sulfur amino acids in the storage proteins of narrow leaf lupin (Lupinus angustifolius) seeds. Variation in sulfur supply to lupin plants affected the sulfur amino acid accumulation in the mature seed. However, when sulfur was in abundant supply, it accumulated to a large extent in oxidized form, rather than reduced form, in the seeds. At all but severely limiting sulfur supply, addition of a transgenic (Tg) sink for organic sulfur resulted in an increase in seed sulfur amino acid content. We hypothesize that demand, or sink strength for organic sulfur, which is itself responsive to environmental sulfur supply, was the first limit to the methionine (Met) and cysteine (Cys) content of wild-type lupin seed protein under most growing conditions. In Tg, soil-grown seeds expressing a foreign Met- and Cys-rich protein, decreased pools of free Met, free Cys, and glutathione indicated that the rate of synthesis of sulfur amino acids in the cotyledon had become limiting. Homeostatic mechanisms similar to those mediating the responses of plants to environmental sulfur stress resulted in an adjustment of endogenous protein composition in Tg seeds, even when grown at adequate sulfur supply. Uptake of sulfur by lupin cotyledons, as indicated by total seed sulfur at maturity, responded positively to increased sulfur supply, but not to increased demand in the Tg seeds. PMID:11891268
Mapping the global potential for marine aquaculture.
Gentry, Rebecca R; Froehlich, Halley E; Grimm, Dietmar; Kareiva, Peter; Parke, Michael; Rust, Michael; Gaines, Steven D; Halpern, Benjamin S
2017-09-01
Marine aquaculture presents an opportunity for increasing seafood production in the face of growing demand for marine protein and limited scope for expanding wild fishery harvests. However, the global capacity for increased aquaculture production from the ocean and the relative productivity potential across countries are unknown. Here, we map the biological production potential for marine aquaculture across the globe using an innovative approach that draws from physiology, allometry and growth theory. Even after applying substantial constraints based on existing ocean uses and limitations, we find vast areas in nearly every coastal country that are suitable for aquaculture. The development potential far exceeds the space required to meet foreseeable seafood demand; indeed, the current total landings of all wild-capture fisheries could be produced using less than 0.015% of the global ocean area. This analysis demonstrates that suitable space is unlikely to limit marine aquaculture development and highlights the role that other factors, such as economics and governance, play in shaping growth trajectories. We suggest that the vast amount of space suitable for marine aquaculture presents an opportunity for countries to develop aquaculture in a way that aligns with their economic, environmental and social objectives.
ERIC Educational Resources Information Center
Eggen, Jerald D.; Mackenzie, R. Alec
1987-01-01
To avoid emergency-driven work environments, crises should be anticipated to the extent possible; steps should be taken to prevent them or limit their consequences. Crises have both internal (personal) and external causes based on poor performance, unreasonable demands, or shifting priorities. Administrators need to cushion deadlines, clarify…
Flexible stocking strategies for adapting to climatic variability
USDA-ARS?s Scientific Manuscript database
As a result of precipitation-induced variability on forage production, ranchers have difficulty matching animal demand with forage availability in their operations. Flexible stocking strategies could more effectively use extra forage in highly productive years and limit risk of overgrazing during dr...
Studies in wave barrier design and levee erosion
USDA-ARS?s Scientific Manuscript database
Increasing demands on limited groundwater resources have created a growing need for the development of surface water resources for irrigation. On-farm reservoirs, along with tailwater recovery systems, can provide a means for reducing dependence on groundwater supplies. These reservoirs are surrou...
10 CFR 300.6 - Emissions inventories.
Code of Federal Regulations, 2010 CFR
2010-01-01
... limited to emissions resulting from combustion of fossil fuels, process emissions, and fugitive emissions... forms of purchased energy to reduce demand, an entity must include the indirect emissions from the... report other forms of indirect emissions, such as emissions associated with employee commuting, materials...
10 CFR 300.6 - Emissions inventories.
Code of Federal Regulations, 2014 CFR
2014-01-01
... limited to emissions resulting from combustion of fossil fuels, process emissions, and fugitive emissions... forms of purchased energy to reduce demand, an entity must include the indirect emissions from the... report other forms of indirect emissions, such as emissions associated with employee commuting, materials...
10 CFR 300.6 - Emissions inventories.
Code of Federal Regulations, 2011 CFR
2011-01-01
... limited to emissions resulting from combustion of fossil fuels, process emissions, and fugitive emissions... forms of purchased energy to reduce demand, an entity must include the indirect emissions from the... report other forms of indirect emissions, such as emissions associated with employee commuting, materials...
10 CFR 300.6 - Emissions inventories.
Code of Federal Regulations, 2013 CFR
2013-01-01
... limited to emissions resulting from combustion of fossil fuels, process emissions, and fugitive emissions... forms of purchased energy to reduce demand, an entity must include the indirect emissions from the... report other forms of indirect emissions, such as emissions associated with employee commuting, materials...
10 CFR 300.6 - Emissions inventories.
Code of Federal Regulations, 2012 CFR
2012-01-01
... limited to emissions resulting from combustion of fossil fuels, process emissions, and fugitive emissions... forms of purchased energy to reduce demand, an entity must include the indirect emissions from the... report other forms of indirect emissions, such as emissions associated with employee commuting, materials...
Applying animal behavior to arid rangeland mangement
USDA-ARS?s Scientific Manuscript database
Livestock production is one of many demands placed on today’s arid rangelands. Therefore, understanding plant and animal biology and their effects on biotic and abiotic landscape components is fundamental if rangelands are to remain ecologically sustainable. One limiting factor to accomplishing posi...
DOT National Transportation Integrated Search
2013-08-01
"Over the last 50 years, advances in the fields of travel behavior research and travel demand forecasting have been : immense, driven by the increasing costs of infrastructure and spatial limitations in areas of high population density : together wit...
Quality Improvement in University Counseling Centers
ERIC Educational Resources Information Center
Maffini, Cara S.; Toth, Paul L.
2017-01-01
University Counseling Centers (UCCs) experience high clinical demands and severe client presentations leaving counselors with limited time and resources to evaluate delivery of services. In this article, we present clinician-friendly quality improvement (QI) strategies used at a large Midwestern university and provide recommendations for…
Nunes, João Pedro; Jacinto, Rita; Keizer, Jan Jacob
2017-04-15
The impacts of climate and associated socio-economic changes on water availability, including supply and demand, quality, and storage volume, were evaluated for the Vale do Gaio reservoir in southern Portugal, located in a dry Mediterranean climate and already under drought stress. The SWAT model was applied with 6 scenarios for 2071-2100, involving two storylines (A1B and B1) with individual changes in climate (-9% rainfall, increasing in winter by +28 to +30%), socio-economic conditions (an increase in irrigation demand by 11%, and a replacement of cereals and pastures by sunflower), and a combination of both. Most future scenarios resulted in lower water availability, due to lower supply (-19 to -27%) combined with higher irrigation demand (+3 to +21%). This resulted in more years with limited irrigation supplies (presently: 28%; scenarios: 37 to 43%), although limitations were mitigated by lower losses to excess discharge. Land-use changes also decreased quality by increasing P concentrations (+29 to +93%). Impacts were more severe in scenario A1B than in B1, and in combined changes than in climate or socio-economic changes only. Water availability was resilient to climate change, as impacts led only to a moderate aggravation of present-day conditions. Lower future water availability could be addressed by supply and demand management strategies and, in the most extreme scenario, by water transfers from regional water reserves; water quality issues could be addressed through land-use policies. Results also highlighted the importance of taking the characteristics of water supply systems into account when designing adaptation measures for future changes. Copyright © 2017 Elsevier B.V. All rights reserved.
Emerging and investigational drugs for premature ejaculation
2016-01-01
Over the past 20−30 years, the premature ejaculation (PE) treatment paradigm, previously limited to behavioural psychotherapy, has expanded to include drug treatment. Pharmacotherapy for PE predominantly targets the multiple neurotransmitters and receptors involved in the control of ejaculation which include serotonin, dopamine, oxytocin, norepinephrine, gamma amino-butyric acid (GABA) and nitric oxide (NO). The objective of this article is to review emerging PE interventions contemporary data on the treatment of PE was reviewed and critiqued using the principles of evidence-based medicine. Multiple well-controlled evidence-based studies have demonstrated the efficacy and safety of selective serotonin reuptake inhibitors (SSRIs) in delaying ejaculation, confirming their role as first-line agents for the medical treatment of lifelong and acquired PE. Daily dosing of SSRIs is likely to be associated with superior fold increases in IELT compared to on-demand SSRIs. On-demand SSRIs are less effective but may fulfill the treatment goals of many patients. Integrated pharmacotherapy and CBT may achieve superior treatment outcomes in some patients. PDE-5 inhibitors alone or in combination with SSRIs should be limited to men with acquired PE secondary to co-morbid ED. New on-demand rapid acting SSRIs, oxytocin receptor antagonists, or single agents that target multiple receptors may form the foundation of more effective future on-demand medication. Current evidence confirms the efficacy and safety of dapoxetine, off-label SSRI drugs, tramadol and topical anaesthetics drugs. Treatment with α1-adrenoceptor antagonists cannot be recommended until the results of large well-designed RCTs are published in major international peer-reviewed medical journals. As our understanding of the neurochemical control of ejaculation improves, new therapeutic targets and candidate molecules will be identified which may increase our pharmacotherapeutic armamentarium. PMID:27652222
On- and off-grid operation of hybrid renewable power plants: When are the economics favorable?
NASA Astrophysics Data System (ADS)
Petrakopoulou, F.; Santana, D.
2016-12-01
Hybrid renewable energy conversion systems offer a good alternative to conventional systems in locations where the extension of the electrical grid is difficult or not economical or where the cost of electricity is high. However, stand-alone operation implies net energy output restrictions (limited to exclusively serve the energy demand of a region), capacity oversizing and large storage facilities. In interconnected areas, on the other hand, the operational restrictions of the power stations change significantly and the efficiencies and costs of renewable technologies become more favorable. In this paper, the operation of three main renewable technologies (CSP, PV and wind) is studied assuming both hybrid and individual operation for both autonomous and inter-connected operation. The case study used is a Mediterranean island of ca. 3,000 inhabitants. Each system is optimized to fully cover the energy demand of the community. In addition, in the on-grid operation cases, it is required that the annual energy generated from the renewable sources is net positive (i.e., the island generates at least as much energy as it uses). It is found that when connected to the grid, hybridization of more than one technology is not required to satisfy the energy demand, as expected. Each of the renewable technologies investigated can satisfy the annual energy demand individually, without significant complications. In addition, the cost of electricity generated with the three studied technologies drops significantly for on-grid applications, when compared to off-grid operation. However, when compared to business-as-usual scenarios in both the on- and off-grid cases, both investigated hybrid and single-technology renewable scenarios are found to be economically viable. A sensitivity analysis reveals the limits of the acceptable costs that make the technologies favorable when compared to conventional alternatives.
Forecasting residential electricity demand in provincial China.
Liao, Hua; Liu, Yanan; Gao, Yixuan; Hao, Yu; Ma, Xiao-Wei; Wang, Kan
2017-03-01
In China, more than 80% electricity comes from coal which dominates the CO2 emissions. Residential electricity demand forecasting plays a significant role in electricity infrastructure planning and energy policy designing, but it is challenging to make an accurate forecast for developing countries. This paper forecasts the provincial residential electricity consumption of China in the 13th Five-Year-Plan (2016-2020) period using panel data. To overcome the limitations of widely used predication models with unreliably prior knowledge on function forms, a robust piecewise linear model in reduced form is utilized to capture the non-deterministic relationship between income and residential electricity consumption. The forecast results suggest that the growth rates of developed provinces will slow down, while the less developed will be still in fast growing. The national residential electricity demand will increase at 6.6% annually during 2016-2020, and populous provinces such as Guangdong will be the main contributors to the increments.
Payments, promotion, and the purple pill.
Ridley, David B
2015-01-01
Understanding competition in the US drug market requires knowing how sensitive demand is to prices. The relevant prices for insured consumers are copayments. There are many studies of copayment elasticity in the health literature, but they are of limited applicability for studies of competition. Because of a paucity of data, such studies typically control for neither competitor copayment nor advertising. Whereas previous studies examined copayment sensitivity when copayments for branded drugs move in unison, this study examines copayment sensitivity when copayments diverge. This study uses unique panel data of insurance copayments and utilization for 77 insurance groups, as well as data on advertising. The results indicate that demand can be much more sensitive to copayment than previously recognized. Manufacturers selling drugs with higher copayments than branded competitors can lose substantial market share. Manufacturers can offset the loss of demand by increasing advertising to physicians, but it is costly. Copyright © 2013 John Wiley & Sons, Ltd.
Ariza-Montes, Antonio; Muniz R, Noel M; Leal-Rodríguez, Antonio L; Leal-Millán, Antonio G
2016-08-01
This paper adopts the Job Demands-Resources (JD-R) model to analyze workplace bullying among teachers. The data used for this research are obtained from the 5th European Working Conditions Survey. Given the objective of this work, a subsample of 261 education employees is collected: 48.7% of these teachers report having experienced workplace bullying (N = 127), while 51.3% indicate not considering themselves as bullied at work (N = 134). In order to test the research model and hypotheses, this study relies on the use of partial least squares (PLS-SEM), a variance-based structural equation modeling method. The study describes a workplace bullying prevalence rate of 4.4% among education employees. This work summarizes an array of outcomes with the aim of proposing, in general, that workplace bullying may be reduced by limiting job demands and increasing job resources.
Liu, Changzheng; Greene, David
2014-12-01
The promotion of greater use of E85, a fuel blend of 85% denatured ethanol, by flex-fuel vehicle owners is an important means of complying with the Renewable Fuel Standard 2. A good understanding of factors affecting E85 demand is necessary for effective policies that promote E85 and for developing models that forecast E85 sales in the United States. In this paper, the sensitivity of aggregate E85 demand to E85 and gasoline prices is estimated, as is the relative availability of E85 versus gasoline. The econometric analysis uses recent data from Minnesota, North Dakota, and Iowa. The more recent data allowmore » a better estimate of nonfleet demand and indicate that the market price elasticity of E85 choice is substantially higher than previously estimated.« less
Regional comparisons of on-site solar potential in the residential and industrial sectors
NASA Astrophysics Data System (ADS)
Gatzke, A. E.; Skewes-Cox, A. O.
1980-10-01
Regional and subregional differences in the potential development of decentralized solar technologies are studied. Two sectors of the economy were selected for intensive analysis: the residential and industrial sectors. The sequence of analysis follows the same general steps: (1) selection of appropriate prototypes within each land use sector disaggregated by census region; (2) characterization of the end-use energy demand of each prototype in order to match an appropriate decentralized solar technology to the energy demand; (3) assessment of the energy conservation potential within each prototype limited by land use patterns, technology efficiency, and variation in solar insolation; and (4) evaluation of the regional and subregional differences in the land use implications of decentralized energy supply technologies that result from the combination of energy demand, energy supply potential, and the subsequent addition of increasingly more restrictive policies to increase the percent contribution of on-site solar energy.
Lin, Bo-Cheng; Chen, Chao-Wen; Chen, Chien-Chou; Kuo, Chiao-Ling; Fan, I-Chun; Ho, Chi-Kung; Liu, I-Chuan; Chan, Ta-Chien
2016-05-25
The occurrence of out-of-hospital cardiac arrest (OHCA) is a critical life-threatening event which frequently warrants early defibrillation with an automated external defibrillator (AED). The optimization of allocating a limited number of AEDs in various types of communities is challenging. We aimed to propose a two-stage modeling framework including spatial accessibility evaluation and priority ranking to identify the highest gaps between demand and supply for allocating AEDs. In this study, a total of 6135 OHCA patients were defined as demand, and the existing 476 publicly available AEDs locations and 51 emergency medical service (EMS) stations were defined as supply. To identify the demand for AEDs, Bayesian spatial analysis with the integrated nested Laplace approximation (INLA) method is applied to estimate the composite spatial risks from multiple factors. The population density, proportion of elderly people, and land use classifications are identified as risk factors. Then, the multi-criterion two-step floating catchment area (MC2SFCA) method is used to measure spatial accessibility of AEDs between the spatial risks and the supply of AEDs. Priority ranking is utilized for prioritizing deployment of AEDs among communities because of limited resources. Among 6135 OHCA patients, 56.85 % were older than 65 years old, and 79.04 % were in a residential area. The spatial distribution of OHCA incidents was found to be concentrated in the metropolitan area of Kaohsiung City, Taiwan. According to the posterior mean estimated by INLA, the spatial effects including population density and proportion of elderly people, and land use classifications are positively associated with the OHCA incidence. Utilizing the MC2SFCA for spatial accessibility, we found that supply of AEDs is less than demand in most areas, especially in rural areas. Under limited resources, we identify priority places for deploying AEDs based on transportation time to the nearest hospital and population size of the communities. The proposed method will be beneficial for optimizing resource allocation while considering multiple local risks. The optimized deployment of AEDs can broaden EMS coverage and minimize the problems of the disparity in urban areas and the deficiency in rural areas.
Scenario-based water resources planning for utilities in the Lake Victoria region
NASA Astrophysics Data System (ADS)
Mehta, Vishal K.; Aslam, Omar; Dale, Larry; Miller, Norman; Purkey, David R.
Urban areas in the Lake Victoria (LV) region are experiencing the highest growth rates in Africa. As efforts to meet increasing demand accelerate, integrated water resources management (IWRM) tools provide opportunities for utilities and other stakeholders to develop a planning framework comprehensive enough to include short term (e.g. landuse change), as well as longer term (e.g. climate change) scenarios. This paper presents IWRM models built using the Water Evaluation And Planning (WEAP) decision support system, for three towns in the LV region - Bukoba (Tanzania), Masaka (Uganda), and Kisii (Kenya). Each model was calibrated under current system performance based on site visits, utility reporting and interviews. Projected water supply, demand, revenues and costs were then evaluated against a combination of climate, demographic and infrastructure scenarios up to 2050. Our results show that water supply in all three towns is currently infrastructure limited; achieving existing design capacity could meet most projected demand until 2020s in Masaka beyond which new supply and conservation strategies would be needed. In Bukoba, reducing leakages would provide little performance improvement in the short-term, but doubling capacity would meet all demands until 2050. In Kisii, major infrastructure investment is urgently needed. In Masaka, streamflow simulations show that wetland sources could satisfy all demand until 2050, but at the cost of almost no water downstream of the intake. These models demonstrate the value of IWRM tools for developing water management plans that integrate hydroclimatology-driven supply to demand projections on a single platform.
Grier, Karissa; Hill, Jennie L; Reese, Felicia; Covington, Constance; Bennette, Franchennette; MacAuley, Lorien; Zoellner, Jamie
2015-10-01
Few published community garden studies have focused on low socio-economic youth living in public housing or used a community-based participatory research approach in conjunction with youth-focused community garden programmes. The objective of the present study was to evaluate the feasibility (i.e. demand, acceptability, implementation and limited-effectiveness testing) of a 10-week experiential theory-based gardening and nutrition education programme targeting youth living in public housing. In this mixed-methods feasibility study, demand and acceptability were measured using a combination of pre- and post-programme surveys and interviews. Implementation was measured via field notes and attendance. Limited-effectiveness was measured quantitatively using a pre-post design and repeated-measures ANOVA tests. Two public housing sites in the Dan River Region of south central Virginia, USA. Forty-three youth (primarily African American), twenty-five parents and two site leaders. The positive demand and acceptability findings indicate the high potential of the programme to be used and be suitable for the youth, parents and site leaders. Field notes revealed numerous implementation facilitators and barriers. Youth weekly attendance averaged 4·6 of 10 sessions. Significant improvements (P<0·05) were found for some (e.g. fruit and vegetable asking self-efficacy, overall gardening knowledge, knowledge of MyPlate recommendations), but not all limited-effectiveness measures (e.g. willingness to try fruits and vegetables, fruit and vegetable eating self-efficacy). This community-based participatory research study demonstrates numerous factors that supported and threatened the feasibility of a gardening and nutrition programme targeting youth in public housing. Lessons learned are being used to adapt and strengthen the programme for future efforts targeting fruit and vegetable behaviours.
Groot, Judith A M; Jonkers, Freerk J; Kievit, Arthur J; Kuijer, P Paul F M; Hoozemans, Marco J M
2017-02-01
Evidence-based advice for return to work (RTW) after anterior cruciate ligament (ACL) reconstruction is not available. Therefore, the objectives of this study were to determine when patients achieve full RTW, and to explore the beneficial and limiting factors for fully RTW after ACL reconstruction. A retrospective cohort study was performed after ACL reconstruction among 185 patients in one hospital. Data from patient files and a questionnaire were used to explore whether patient-, injury-, surgery-, sports-, work- and rehabilitation-related factors are beneficial or limiting for fully RTW after ACL reconstruction, using a backward stepwise logistic regression analysis. Of the 125 (68%) patients that returned the questionnaire, 36 were not part of the working population. Of the remaining 89 patients, 82 patients (92%) had returned fully to work at follow-up. The median time to fully RTW was 78 days. In the final regression model, which explained 29% of the variance, a significant OR of 5.4 (90% CI 2.2-13.1) for RTW > 78 days was observed for patients performing heavy knee-demanding work compared to patients performing light knee-demanding work. In addition, a significant and positive OR (1.6, 90% CI 1.2-1.9) for the number of weeks walking with the aid of crutches for RTW > 78 days was observed in the final model. After ACL reconstruction, 92% of the patients fully return to work at a median time of 78 days. The significant predictors for fully RTW > 78 days are performing heavy knee-demanding work and a longer period of walking aided with crutches after ACL reconstruction.
Oxygen supply limits the heat tolerance of lizard embryos.
Smith, Colton; Telemeco, Rory S; Angilletta, Michael J; VandenBrooks, John M
2015-04-01
The mechanisms that set the thermal limits to life remain uncertain. Classically, researchers thought that heating kills by disrupting the structures of proteins or membranes, but an alternative hypothesis focuses on the demand for oxygen relative to its supply. We evaluated this alternative hypothesis by comparing the lethal temperature for lizard embryos developing at oxygen concentrations of 10-30%. Embryos exposed to normoxia and hyperoxia survived to higher temperatures than those exposed to hypoxia, suggesting that oxygen limitation sets the thermal maximum. As all animals pass through an embryonic stage where respiratory and cardiovascular systems must develop, oxygen limitation may limit the thermal niches of terrestrial animals as well as aquatic ones. © 2015 The Author(s) Published by the Royal Society. All rights reserved.
1982-06-01
start/stop chiller optimization , and demand limiting were added. The system monitors a 7,000 ton chiller plant and controls 74 air handlers. The EMCS does...Modify analog limits. g. Adjust setpoints of selected controllers. h. Select manual or automatic control modes. i. Enable and disable individual points...or event schedules and controller setpoints ; make nonscheduled starts and stops of equipment or disable field panels when required for routine
Outer Limits of Biotechnologies: A Jewish Perspective
Loike, John D.; Kadish, Alan
2018-01-01
A great deal of biomedical research focuses on new biotechnologies such as gene editing, stem cell biology, and reproductive medicine, which have created a scientific revolution. While the potential medical benefits of this research may be far-reaching, ethical issues related to non-medical applications of these technologies are demanding. We analyze, from a Jewish legal perspective, some of the ethical conundrums that society faces in pushing the outer limits in researching these new biotechnologies. PMID:29406847
Improving Survival and Promoting Respiratory Motor Function After Cervical Spinal Cord Injury
2017-09-01
ventilator in order to survive. Use of the ventilator severely limits the quality of life of those injured and dramatically increases the demand for health...care for cervical SCI patients so as to lead to an improved quality of life , better-quality health care management, and improved functional outcomes...mechanical ventilator in order to survive. Use of the ventilator severely limits the quality of life of those injured and dramatically increases the
Trading the Economic Value of Unsatisfied Municipal Water Demand
NASA Astrophysics Data System (ADS)
Telfah, Dua'a. B.; Minciardi, Riccardo; Roth, Giorgio
2018-06-01
Modelling and optimization techniques for water resources allocation are proposed to identify the economic value of the unsatisfied municipal water demand against demands emerging from other sectors. While this is always an important step in integrated water resource management perspective, it became crucial for water scarce Countries. In fact, since the competition for the resource is high, they are in crucial need to trade values which will help them in satisfying their policies and needs. In this framework, hydro-economic, social equity and environmental constraints need to be satisfied. In the present study, a hydro-economic decision model based on optimization schemes has been developed for water resources allocation, that enable the evaluation of the economic cost of a deficiency in fulfilling the municipal demand. Moreover, the model enables efficient water resources management, satisfying the demand and proposing additional water resources options. The formulated model is designed to maximize the demand satisfaction and minimize water production cost subject to system priorities, preferences and constraints. The demand priorities are defined based on the effect of demand dissatisfaction, while hydrogeological and physical characteristics of the resources are embedded as constraints in the optimization problem. The application to the City of Amman is presented. Amman is the Capital City of the Hashemite Kingdom of Jordan, a Country located in the south-eastern area of the Mediterranean, on the East Bank of the Jordan River. The main challenge for Jordan, that threat the development and prosperity of all sectors, is the extreme water scarcity. In fact, Jordan is classified as semi-arid to arid region with limited financial resources and unprecedented population growth. While the easy solution directly goes to the simple but expensive approach to cover the demand, case study results show that the proposed model plays a major role in providing directions to decision makers to orient their policies and strategies in order to achieve sustainability of scarce water resources, satisfaction of the minimum required demand as well as financial sustainability. In addition, results map out national needs and priorities that are crucial in understanding and controlling the complexity of Jordan's water sector, mainly for the city of Amman.
USDA-ARS?s Scientific Manuscript database
Technological advances in irrigated agriculture are crucial to meeting the challenge of increasing demand for agricultural products given limited quality and quantity of water resources for irrigation, impacts of climate variability, and the need to reduce environmental impacts. Multidisciplinary ap...
Implementation Evaluation in a Private Nonprofit Setting: A Mixed-Methods Approach
ERIC Educational Resources Information Center
Walker, Jacquelyn Ann
2013-01-01
Demand for quality service provision in the human services industry requires that private nonprofit organizations have the administrative and management capacities to ensure successful implementation and sustain staff development programs. Unfamiliarity with implementation challenges, and limited awareness of implementation strategies, can trigger…
29 CFR 32.15 - Preemployment inquiries.
Code of Federal Regulations, 2010 CFR
2010-07-01
... official should make a functional assessment of the physical or mental demands of the jobs in order to... handicap. A recipient may, however, make preemployment inquiry into an applicant's ability to perform job... sufficient information regarding any functional limitations relevant to proper job placement or referral to...
Measuring the erosion of an irrigation reservoir levee
USDA-ARS?s Scientific Manuscript database
Increasing demands on limited groundwater resources in the Arkansas and Mississippi alluvial floodplain (commonly called the Delta) have created a growing need for the development of surface water resources for irrigation. On-farm reservoirs, along with tail-water recovery systems, are used to stor...
Political Parody and Public Culture
ERIC Educational Resources Information Center
Hariman, Robert
2008-01-01
Parody and related forms of political humor are essential resources for sustaining democratic public culture. They do so by exposing the limits of public speech, transforming discursive demands into virtual images, setting those images before a carnivalesque audience, and celebrating social leveling while decentering all discourses within the…
A Course on Reconfigurable Processors
ERIC Educational Resources Information Center
Shoufan, Abdulhadi; Huss, Sorin A.
2010-01-01
Reconfigurable computing is an established field in computer science. Teaching this field to computer science students demands special attention due to limited student experience in electronics and digital system design. This article presents a compact course on reconfigurable processors, which was offered at the Technische Universitat Darmstadt,…
The Need for Institutional Fiscal Responsibility
ERIC Educational Resources Information Center
Institute for Higher Education Policy, 2011
2011-01-01
Colleges and universities across the nation face a number of economic and social conditions that affect institutional operations. Limited financial resources due to the nation's economic recession, increased calls for improved degree productivity to meet civic and labor market demands, and shifting demographic patterns create a challenging…
75 FR 67113 - Sparklers From China
Federal Register 2010, 2011, 2012, 2013, 2014
2010-11-01
.... (12) Identify significant changes, if any, in the supply and demand conditions or business cycle for..., Deputy Agency Ethics Official, at 202-205-3088. Limited disclosure of business proprietary information... exporter of the Subject Merchandise, a U.S. or foreign trade or business association, or another interested...
76 FR 11273 - Ammonium Nitrate From Russia
Federal Register 2010, 2011, 2012, 2013, 2014
2011-03-01
... significant changes, if any, in the supply and demand conditions or business cycle for the Domestic Like..., Deputy Agency Ethics Official, at 202-205-3088. Limited disclosure of business proprietary information... Subject Merchandise, a U.S. or foreign trade or business association, or another interested party...
75 FR 67102 - Cased Pencils From China
Federal Register 2010, 2011, 2012, 2013, 2014
2010-11-01
.... (12) Identify significant changes, if any, in the supply and demand conditions or business cycle for..., Deputy Agency Ethics Official, at 202-205-3088. Limited disclosure of business proprietary information... Subject Merchandise, a U.S. or foreign trade or business association, or another interested party...
75 FR 62141 - Glycine From China
Federal Register 2010, 2011, 2012, 2013, 2014
2010-10-07
.... (12) Identify significant changes, if any, in the supply and demand conditions or business cycle for... Official, at 202- 205-3088. Limited disclosure of business proprietary information (BPI) under an... exporter of the Subject Merchandise, a U.S. or foreign trade or business association, or another interested...
Instructional Coaching as High-Quality Professional Development
ERIC Educational Resources Information Center
Desimone, Laura M.; Pak, Katie
2017-01-01
In response to policy initiatives calling for the implementation of evidence-based classroom practice, instructional coaches are frequently utilized as providers of professional development (PD). Despite the demand for instructional coaches, there is little empirical evidence that coaching improves teacher practice. We address this limitation by…
Will Invertebrates Require Increasingly Carbon-Rich Food in a Warming World?
Anderson, Thomas R; Hessen, Dag O; Boersma, Maarten; Urabe, Jotaro; Mayor, Daniel J
2017-12-01
Elevated temperature causes metabolism and respiration to increase in poikilothermic organisms. We hypothesized that invertebrate consumers will therefore require increasingly carbon-rich diets in a warming environment because the increased energetic demands are primarily met using compounds rich in carbon, that is, carbohydrates and lipids. Here, we test this hypothesis using a new stoichiometric model that has carbon (C) and nitrogen (N) as currencies. Model predictions did not support the hypothesis, indicating instead that the nutritional requirements of invertebrates, at least in terms of food quality expressed as C∶N ratio, may change little, if at all, at elevated temperature. Two factors contribute to this conclusion. First, invertebrates facing limitation by nutrient elements such as N have, by default, excess C in their food that can be used to meet the increased demand for energy in a warming environment, without recourse to extra dietary C. Second, increased feeding at elevated temperature compensates for the extra demands of metabolism to the extent that, when metabolism and intake scale equally with temperature (have the same Q 10 ), the relative requirement for dietary C and N remains unaltered. Our analysis demonstrates that future climate-driven increases in the C∶N ratios of autotroph biomass will likely exacerbate the stoichiometric mismatch between nutrient-limited invertebrate grazers and their food, with important consequences for C sequestration and nutrient cycling in ecosystems.
Water stress, water salience, and the implications for water supply planning
NASA Astrophysics Data System (ADS)
Garcia, M. E.; Islam, S.
2017-12-01
Effectively addressing the water supply challenges posed by urbanization and climate change requires a holistic understanding of the water supply system, including the impact of human behavior on system dynamics. Decision makers have limits to available information and information processing capacity, and their attention is not equally distributed among risks. The salience of a given risk is higher when increased attention is directed to it and though perceived risk may increase, real risk does not change. Relevant to water supply planning is how and when water stress results in an increased salience of water risks. This work takes a socio-hydrological approach to develop a water supply planning model that includes water consumption as an endogenous variable, in the context of Las Vegas, NV. To understand the benefits and limitations of this approach, this model is compared to a traditional planning model that uses water consumption scenarios. Both models are applied to project system reliability and water stress under four streamflow and demographic scenarios, and to assess supply side responses to changing conditions. The endogenous demand model enables the identification of feedback between both supply and demand management decisions on future water consumption and system performance. This model, while specific to the Las Vegas case, demonstrates a prototypical modeling framework capable of examining water-supply demand interactions by incorporating water stress driven conservation.
Stoknes, K; Scholwin, F; Krzesiński, W; Wojciechowska, E; Jasińska, A
2016-10-01
At urban locations certain challenges are concentrated: organic waste production, the need for waste treatment, energy demand, food demand, the need for circular economy and limited area for food production. Based on these factors the project presented here developed a novel technological approach for processing organic waste into new food. In this system, organic waste is converted into biogas and digester residue. The digester residue is being used successfully as a stand-alone fertilizer as well as main substrate component for vegetables and mushrooms for the first time - a "digeponics" system - in a closed new low energy greenhouse system with dynamic soap bubble insulation. Biogas production provides energy for the process and CO2 for the greenhouse. With very limited land use highly efficient resource recycling was established at pilot scale. In the research project it was proven that a low energy dynamic bubble insulated greenhouse can be operated continuously with 80% energy demand reduction compared to conventional greenhouses. Commercial crop yields were achieved based on fertilization with digestate; in individual cases they were even higher than the control yields of vegetables such as tomatoes, cucumber and lettuce among others. For the first time an efficient direct use of digestate as substrate and fertilizer has been developed and demonstrated. Copyright © 2016 Elsevier Ltd. All rights reserved.
Kornrumpf, Benthe; Sommer, Werner
2015-09-01
Due to capacity limitation, visual attention must be focused to a limited region of the visual field. Nevertheless, it is assumed that the size of that region may vary with task demands. We aimed to obtain direct evidence for the modulation of visuospatial attention as a function of foveal and parafoveal task load. Participants were required to fixate the center word of word triplets. In separate task blocks, either just the fixated word or both the fixated and the parafoveal word to the right should be semantically classified. The spatiotemporal distribution of attention was assessed with task-irrelevant probes flashed briefly at center or parafoveal positions, during or in between word presentation trials. The N1 component of the ERP elicited by intertrial probes at possible target positions increased with task demands within a block. These results suggest the recruitment of additional attentional resources rather than a redistribution of a fixed resource pool, which persists across trials. © 2015 Society for Psychophysiological Research.
Compact, high-speed algorithm for laying out printed circuit board runs
NASA Astrophysics Data System (ADS)
Zapolotskiy, D. Y.
1985-09-01
A high speed printed circuit connection layout algorithm is described which was developed within the framework of an interactive system for designing two-sided printed circuit broads. For this reason, algorithm speed was considered, a priori, as a requirement equally as important as the inherent demand for minimizing circuit run lengths and the number of junction openings. This resulted from the fact that, in order to provide psychological man/machine compatibility in the design process, real-time dialog during the layout phase is possible only within limited time frames (on the order of several seconds) for each circuit run. The work was carried out for use on an ARM-R automated work site complex based on an SM-4 minicomputer with a 32K-word memory. This limited memory capacity heightened the demand for algorithm speed and also tightened data file structure and size requirements. The layout algorithm's design logic is analyzed. The structure and organization of the data files are described.
Nitrogen dynamics in managed boreal forests: Recent advances and future research directions.
Sponseller, Ryan A; Gundale, Michael J; Futter, Martyn; Ring, Eva; Nordin, Annika; Näsholm, Torgny; Laudon, Hjalmar
2016-02-01
Nitrogen (N) availability plays multiple roles in the boreal landscape, as a limiting nutrient to forest growth, determinant of terrestrial biodiversity, and agent of eutrophication in aquatic ecosystems. We review existing research on forest N dynamics in northern landscapes and address the effects of management and environmental change on internal cycling and export. Current research foci include resolving the nutritional importance of different N forms to trees and establishing how tree-mycorrhizal relationships influence N limitation. In addition, understanding how forest responses to external N inputs are mediated by above- and belowground ecosystem compartments remains an important challenge. Finally, forestry generates a mosaic of successional patches in managed forest landscapes, with differing levels of N input, biological demand, and hydrological loss. The balance among these processes influences the temporal patterns of stream water chemistry and the long-term viability of forest growth. Ultimately, managing forests to keep pace with increasing demands for biomass production, while minimizing environmental degradation, will require multi-scale and interdisciplinary perspectives on landscape N dynamics.
The potential for land sparing to offset greenhouse gas emissions from agriculture
NASA Astrophysics Data System (ADS)
Lamb, Anthony; Green, Rhys; Bateman, Ian; Broadmeadow, Mark; Bruce, Toby; Burney, Jennifer; Carey, Pete; Chadwick, David; Crane, Ellie; Field, Rob; Goulding, Keith; Griffiths, Howard; Hastings, Astley; Kasoar, Tim; Kindred, Daniel; Phalan, Ben; Pickett, John; Smith, Pete; Wall, Eileen; Zu Ermgassen, Erasmus K. H. J.; Balmford, Andrew
2016-05-01
Greenhouse gas emissions from global agriculture are increasing at around 1% per annum, yet substantial cuts in emissions are needed across all sectors. The challenge of reducing agricultural emissions is particularly acute, because the reductions achievable by changing farming practices are limited and are hampered by rapidly rising food demand. Here we assess the technical mitigation potential offered by land sparing--increasing agricultural yields, reducing farmland area and actively restoring natural habitats on the land spared. Restored habitats can sequester carbon and can offset emissions from agriculture. Using the UK as an example, we estimate net emissions in 2050 under a range of future agricultural scenarios. We find that a land-sparing strategy has the technical potential to achieve significant reductions in net emissions from agriculture and land-use change. Coupling land sparing with demand-side strategies to reduce meat consumption and food waste can further increase the technical mitigation potential--however, economic and implementation considerations might limit the degree to which this technical potential could be realized in practice.
NASA Astrophysics Data System (ADS)
Abe, R.; Hamada, K.; Hirata, N.; Tamura, R.; Nishi, N.
2015-05-01
As well as the BIM of quality management in the construction industry, demand for quality management of the manufacturing process of the member is higher in shipbuilding field. The time series of three-dimensional deformation of the each process, and are accurately be grasped strongly demanded. In this study, we focused on the shipbuilding field, will be examined three-dimensional measurement method. The shipyard, since a large equipment and components are intricately arranged in a limited space, the installation of the measuring equipment and the target is limited. There is also the element to be measured is moved in each process, the establishment of the reference point for time series comparison is necessary to devise. In this paper will be discussed method for measuring the welding deformation in time series by using a total station. In particular, by using a plurality of measurement data obtained from this approach and evaluated the amount of deformation of each process.
Ribeiro, José Mendes; Inglez-Dias, Aline
2011-12-01
We studied Brazilian policies on mental health with respect to normative, supply and demand and financing aspects. We concluded that the sustainability of innovations in psychiatric reform depends on enhanced financing and integration with primary care community services, on the overall performance of SUS and the reduction of autonomous and exclusive services in primary care. There is high and rising pressure in demand for services measured in DALY and the incidence of disease. The reduction observed in psychiatric beds was accompanied by the systemic reduction, though with selective reduction for psychiatric hospitalizations. CAPS services have institutional limits due to the model adopted of direct public administration and local government capacity. Secondary data available show that: (i) SUS has a virtual monopoly on general outpatient and hospital services; (ii) mental health specialists belong mostly to SUS; (iii) most mental health services are outpatient services; (iv) few CAPS have day-bed services available; and (v) there is reduced federal financing for these innovations.
Intensive care medicine and organ donation: exploring the last frontiers?
Escudero, D; Otero, J
2015-01-01
The main, universal problem for transplantation is organ scarcity. The gap between offer and demand grows wider every year and causes many patients in waiting list to die. In Spain, 90% of transplants are done with organs taken from patients deceased in brain death but this has a limited potential. In order to diminish organ shortage, alternative strategies such as donations from living donors, expanded criteria donors or donation after circulatory death, have been developed. Nevertheless, these types of donors also have their limitations and so are not able to satisfy current organ demand. It is necessary to reduce family denial and to raise donation in brain death thus generalizing, among other strategies, non-therapeutic elective ventilation. As intensive care doctors, cornerstone to the national donation programme, we must consolidate our commitment with society and organ transplantation. We must contribute with the values proper to our specialization and try to reach self-sufficiency by rising organ obtainment. Copyright © 2015 Elsevier España, S.L.U. and SEMICYUC. All rights reserved.
Characteristic of leachate at Alor Pongsu Landfill Site, Perak, Malaysia: A comparative study
NASA Astrophysics Data System (ADS)
Nor Farhana Zakaria, Siti; Aziz, Hamidi Abdul
2018-04-01
Leachate is a harmful by product generated from the landfill site. Leachate contains a high concentration of pollutant which can cause serious pollution to environmental. In this study, characteristics of leachate in Alor Pongsu Landfill Site (APLS) were monitored and analyzed according to the Standard Methods for the Examination of Water and Wastewater (2005). Composition in leachate at APLS was monitored for one year starting from January 2015 until January 2016. Nine parameters were monitored including color, chemical oxygen demand (COD), biological oxygen demand (BOD5), ammoniacal nitrogen (NH3-N), biodegradability ratio (BOD5/COD), temperature, dissolved oxygen (DO), total dissolved solid (TDS) and pH. Based on the analysis, Alor Pongsu Landfill leachate was categorized as stabilized landfill leachate by referring to the BOD5/COD < 0.1. Comparison with allowable discharge limits for leachate shows that most of parameters exceeded the standard discharge limitation. Thus, proper treatment is needed before leachate can be discharged to the environment.
Waldinger, Marcel D; Schweitzer, Dave H; Olivier, Berend
2005-01-01
Recently, the idea has emerged that on-demand use of serotonin reuptake inhibitors (SSRIs), particularly short half-life, should be equally effective in delaying ejaculation as daily SSRI treatment of premature ejaculation. To provide evidence that SSRI-induced ejaculation delay is mainly dependent on pharmacodynamic properties of the drug and hardly on pharmacokinetic factors, and that combined SSRI administration with specific 5-hydroxytryptamine (5-HT) receptor antagonism leads acutely to stronger ejaculation delay than acute SSRI monoadministration. We performed a detailed analysis of serotonin neurotransmission and reviewed animal studies with 5-HT(1A) receptor antagonists. In addition, we critically reviewed existing on-demand SSRI treatments publications and the current debate on a definition of premature ejaculation. Intravaginal ejaculation latency time (IELT). Acute SSRI administration leads to only a mild or no increase of 5-HT neurotransmission and concomitant stimulation of postsynaptic 5-HT receptors. Existing on-demand SSRI treatment studies suffer from methodological insufficiencies, and the reported high-fold increases of ejaculation time contradict with neuropharmacological insights from serotonin metabolism. Animal studies show that SSRI coadministration with 5-HT(1A) receptor antagonists significantly increases the ejaculation time acutely compared to acute SSRI monoadministration. On-demand SSRI treatment has less ejaculation-delaying effects than daily SSRI treatment. SSRIs with a short half-life are likely leading to much less ejaculation delay than current registered SSRIs. Combined use of SSRIs with 5-HT(1A) receptor antagonists increases the likelihood of clinically relevant ejaculation delay after on-demand treatment. On-demand SSRIs with short half-life that insufficiently delay ejaculation in men with IELTs less than 1 minute should be called ejaculation-delaying drugs rather than drugs against premature ejaculation.
Lin, Chia-Der; Lin, Blossom Yen-Ju
2016-08-22
In the education field, learning experiences are considered learners' properties and are viewed as a key determinant in explaining learners' learning processes, especially for training novices such as clerks with varying levels of commitment to the medical profession. This study explored whether clerks' achievement goal motivation orientations might buffer the negative well-being to a certain extent, considering their training demands during clinical training. Ninety-four clerks at a tertiary medical center were longitudinally traced during their 2-year clerkship spanning from September 2013 to April 2015. Web-based, validated, structured, self-administered questionnaires were used to evaluate the clerks' properties of achievement goal motivation orientation and personal background at the beginning of the clerkship. Regular surveys were conducted to evaluate their perceptions of training demands and burnout at each specialty rotation. Overall, 2230 responses were analyzed, and linear mixed-effects models were used to examine the repeated measures of the clerks. The results revealed that higher perceived psychological and physical demands of training were related to higher perceived burnout during the 2-year clerkship. Although both the clerks' task and ego orientations were related to reduced burnout (direct effects), only task orientation was indicated to exert a buffering effect on their perception of physical demands on burnout in the 1st year of the clerkship. Considering the negative effects of training demands (psychological and physical), we observed a limited effect of the task achievement motivation orientation of medical students; therefore, additional studies might focus on strategies to facilitate medical students in clerkships in addressing both the psychological and physical demands inherent in training workplaces to improve their learning experience and well-being.
Sabbath, Erika L; Andel, Ross; Zins, Marie; Goldberg, Marcel; Berr, Claudine
2016-10-01
Psychosocial work characteristics may predict cognitive functioning after retirement. However, little research has explored specific cognitive domains associated with psychosocial work environments. Our study tested whether exposure to job demands, job control and their combination during working life predicted post-retirement performance on eight cognitive tests. We used data from French GAZEL cohort members who had undergone post-retirement cognitive testing (n=2149). Psychosocial job characteristics were measured on average for 4 years before retirement using Karasek's Job Content Questionnaire (job demands, job control and demand-control combinations). We tested associations between these exposures and post-retirement performance on tests for executive function, visual-motor speed, psychomotor speed, verbal memory, and verbal fluency using ordinary least squares regression. Low job control during working life was negatively associated with executive function, psychomotor speed, phonemic fluency and semantic fluency after retirement (p's<0.05), even after adjustment for demographics, socioeconomic status, health and social behaviours and vascular risk factors. Both passive (low-demand, low-control) and high-strain (high-demand, low-control) jobs were associated with lower scores on phonemic and semantic fluency when compared to low-strain (low-demand, high-control) jobs. Low job control, in combination with both high and low-job demands, is associated with post-retirement deficits in some, but not all, cognitive domains. In addition to work stress, associations between passive work and subsequent cognitive function may implicate lack of cognitive engagement at work as a risk factor for future cognitive difficulties. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/
The experience of demanding work environments in younger workers.
Winding, T N; Labriola, M; Nohr, E A; Andersen, J H
2015-06-01
Investigating whether certain individual or background characteristics are associated with an increased risk of experiencing an excessively demanding work environment in younger workers may help to reduce future inequality in health and maximize their labour market participation. To describe the work environment of Danish 20- to 21-year olds and to investigate the influence of family socioeconomic background and individual characteristics at age 14-15 on later experience of physical and psychosocial work environments. We obtained information on subjects' school performance, vulnerability, health and parental socioeconomic status from registers and a questionnaire completed in 2004. A questionnaire concerning eight measures of subjects' psychosocial and physical work environment in 2010 was used to determine the outcomes of interest. The study population consisted of 679 younger workers aged 20-21. The psychosocial work environment was in general good but younger workers experienced more demanding physical work than the general working population. Overall, individual as well as family factors had a limited impact on their assessment of the work environment. Low self-esteem at age 14-15 was associated with experiencing high demands and lack of trust and fairness at work, whereas low parental socioeconomic status was associated with a demanding physical work environment. This study showed a social gradient in experiencing a demanding physical work environment at age 20-21. The psychosocial work environment experienced by younger workers was generally good, but vulnerable young people may need special attention to protect them from or prepare them for psychosocially demanding jobs later in life. © The Author 2015. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Occupational physical demand and risk of hip fracture in older women.
Palumbo, Aimee J; Michael, Yvonne L; Burstyn, Igor; Lee, Brian K; Wallace, Robert
2015-08-01
Hip fractures are leading causes of disability, morbidity and mortality among older women. Since physical activity helps maintain physical functioning and bone mineral density, occupational physical demand may influence fracture risk. This study investigates the association of occupational physical demand with hip fracture incidence among women. The Women's Health Initiative Observational Study is a multiethnic cohort of 93,676 postmenopausal women, 50-79 years of age at enrolment, enrolled from 1994 to 1998 at 40 geographically diverse clinical centres throughout the USA. Outcomes including hip fractures were assessed annually and up to 3 jobs held since age 18 years were reported by each woman. Occupational physical demand levels were assigned for each job through linkage of occupational titles with Standard Occupational Codes and the Occupational Information Network. Average, cumulative and peak physical demand scores both before and after menopause and throughout women's work life were estimated. Women were followed through 2010 for an average of 11.5 years; 1834 hip fractures occurred during this time. We did not observe an overall association of occupational physical demand with subsequent risk of hip fracture after adjusting for age, race/ethnicity, birth region and education. Previous research on occupations and hip fracture risk in women is inconclusive. This study was able to take critical risk periods into account and control for confounding factors in a large cohort of older women to show that overall occupational physical demand neither increases nor decreases risk of hip fracture later in life. 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.
The role of job strain on return to work after carpal tunnel surgery
Gimeno, D; Amick, B; Habeck, R; Ossmann, J; Katz, J
2005-01-01
Aims: To examine the impact of job strain (that is, high psychological job demands and low job control) on return to work and work role functioning at two months, six months, or both, following carpal tunnel release surgery. Methods: A community based cohort of carpal tunnel syndrome (CTS) patients from physician practices was recruited between April 1997 and October 1998 throughout Maine (USA). 128 patients at two months and 122 at six months completed all relevant questions. A three level outcome variable indicated whether patients had: (1) returned to work functioning successfully, (2) returned to work functioning with limitations, or (3) not returned to work for health reasons. Two job strain measures were created: one, by combining psychological job demands and job control; and two, by dividing demands by control. Ordinal logistic regression was used to identify predictors of the three level work outcome variable. Results: After adjustment, workers with high demands and high control (active work) were less likely to successfully return to work (OR = 0.22; p = 0.014) at two months. Having a job with higher demands than job control (high strain) predicted not returning to work or returning to work but not successfully meeting job demands (OR = 0.14; p = 0.001), at six months. Conclusions: The findings underscore the role of psychosocial work conditions, as defined by the Karasek demand-control model, in explaining a worker's return to work. Clinicians, researchers, and employers should consider a multidimensional and integrative model of successful work role functioning upon return to work. Moreover, since the evidence of the effects of work process changes on the reduction of CTS is very scarce, these findings point to the opportunity for collaborative workplace interventions to facilitate successful return to work. PMID:16234404
Pollution source localization in an urban water supply network based on dynamic water demand.
Yan, Xuesong; Zhu, Zhixin; Li, Tian
2017-10-27
Urban water supply networks are susceptible to intentional, accidental chemical, and biological pollution, which pose a threat to the health of consumers. In recent years, drinking-water pollution incidents have occurred frequently, seriously endangering social stability and security. The real-time monitoring for water quality can be effectively implemented by placing sensors in the water supply network. However, locating the source of pollution through the data detection obtained by water quality sensors is a challenging problem. The difficulty lies in the limited number of sensors, large number of water supply network nodes, and dynamic user demand for water, which leads the pollution source localization problem to an uncertainty, large-scale, and dynamic optimization problem. In this paper, we mainly study the dynamics of the pollution source localization problem. Previous studies of pollution source localization assume that hydraulic inputs (e.g., water demand of consumers) are known. However, because of the inherent variability of urban water demand, the problem is essentially a fluctuating dynamic problem of consumer's water demand. In this paper, the water demand is considered to be stochastic in nature and can be described using Gaussian model or autoregressive model. On this basis, an optimization algorithm is proposed based on these two dynamic water demand change models to locate the pollution source. The objective of the proposed algorithm is to find the locations and concentrations of pollution sources that meet the minimum between the analogue and detection values of the sensor. Simulation experiments were conducted using two different sizes of urban water supply network data, and the experimental results were compared with those of the standard genetic algorithm.
Non-Foster Circuits for High Performance Antennas: Advantages and Practical Limitations
NASA Astrophysics Data System (ADS)
Jacob, Minu Mariam
The demand for miniaturized, broadband communication systems has created a need for electrically small, broadband antennas. However, all passive electrically small antennas have a fundamental gain-bandwidth limitation related to their electrical size, as first described by Wheeler and Chu. This limitation can be overcome using active non-Foster circuits (negative inductors and/or negative capacitors), which can deliver a broadband input match with active matching techniques, or can help reduce phase dispersion using negative delay effects. This thesis will illustrate the advantages of non-Foster circuits in obtaining broadband small antennas, in addition to examining their practical limitations due to noise in receive applications, and nonlinearity in transmit applications.
Barriers to Household Risk Management: Evidence from India
Cole, Shawn; Giné, Xavier; Tobacman, Jeremy; Townsend, Robert; Topalova, Petia; Vickery, James
2012-01-01
Why do many households remain exposed to large exogenous sources of non-systematic income risk? We use a series of randomized field experiments in rural India to test the importance of price and non-price factors in the adoption of an innovative rainfall insurance product. Demand is significantly price sensitive, but widespread take-up would not be achieved even if the product offered a payout ratio comparable to U.S. insurance contracts. We present evidence suggesting that lack of trust, liquidity constraints and limited salience are significant non-price frictions that constrain demand. We suggest contract design improvements to mitigate these frictions. PMID:24765234
Sustainability of Fossil Fuels
NASA Astrophysics Data System (ADS)
Lackner, K. S.
2002-05-01
For a sustainable world economy, energy is a bottleneck. Energy is at the basis of a modern, technological society, but unlike materials it cannot be recycled. Energy or more precisely "negentropy" (the opposite of entropy) is always consumed. Thus, one either accepts the use of large but finite resources or must stay within the limits imposed by dilute but self-renewing resources like sunlight. The challenge of sustainable energy is exacerbated by likely growth in world energy demand due to increased population and increased wealth. Most of the world still has to undergo the transition to a wealthy, stable society with the near zero population growth that characterizes a modern industrial society. This represents a huge unmet demand. If ten billion people were to consume energy like North Americans do today, world energy demand would be ten times higher. In addition, technological advances while often improving energy efficiency tend to raise energy demand by offering more opportunity for consumption. Energy consumption still increases at close to the 2.3% per year that would lead to a tenfold increase over the course of the next century. Meeting future energy demands while phasing out fossil fuels appears extremely difficult. Instead, the world needs sustainable or nearly sustainable fossil fuels. I propose the following definition of sustainable under which fossil fuels would well qualify: The use of a technology or resource is sustainable if the intended and unintended consequences will not force its abandonment within a reasonable planning horizon. Of course sustainable technologies must not be limited by resource depletion but this is only one of many concerns. Environmental impacts, excessive land use, and other constraints can equally limit the use of a technology and thus render it unsustainable. In the foreseeable future, fossil fuels are not limited by resource depletion. However, environmental concerns based on climate change and other environmental effects of injecting excess carbon into the environment need to be eliminated before fossil fuels can be considered sustainable. Sustainable fossil fuel use would likely rely on abundant, low-grade hydrocarbons like coal, tar, and shale. It would require a closed cycle approach in which carbon is extracted from the ground, processed for its energy content, and returned into safe and stable sinks for permanent disposal. Such sequestration technologies already exist and more advanced approaches that could maintain access to fossil energy for centuries are on the drawing boards. I will review these options and outline a pathway towards a zero emission fossil fuel based economy that could provide energy at prices comparable to those of today for several centuries. A successful implementation will depend not only on technological advances but also on the development of economic institutions that allow one to pay for the required carbon management. If done correctly the markets will decide whether renewable energy, or sustainable fossil energy provides a better choice.
Many municipalities are facing the call to increase nutrient removal performance of their wastewater treatment plants in order to limit the impacts of eutrophication on the receiving waterbodies. The associated upgrades often demand investment in new technologies and increases in...
Optimizing preplant irrigation for maize under limited water in the High Plains
USDA-ARS?s Scientific Manuscript database
Due to inadequate well capacities, many farmers cannot meet inseason crop evapotranspiration demands. Some farmers apply preplant (preseason) irrigation to buffer the crop between irrigation or rainfall events during the season. A simulation study was conducted to assess the effect of preplant irrig...
ERIC Educational Resources Information Center
Kehoe, Thomas J.
1977-01-01
The instrumental method for detecting total organic carbon (TOC) in water samples is detailed. The method's limitations are discussed and certain precautions that must be taken are emphasized. The subject of TOC versus COD and BOD is investigated and TOC is determined to be a valid indication of biological demand. (BT)
Data sharing in the ag community - what are current challenges, benefits, and opportunities
USDA-ARS?s Scientific Manuscript database
The model for building agronomic science today and into the future to meet global food demands with limited resources will be through public-private data acquisition, sharing, and collaborative analysis. The public perspective focuses on preserving natural resources. The private perspective focuses ...
ERIC Educational Resources Information Center
Padron, Eduardo J.
2009-01-01
Today, America faces a shifting and demanding economic and workforce environment. Americans know that the workplace is changing but not where it's heading. Each demonstration of the latest breakthrough technology can have enormous impact on the society, opening up entire new industries and markets and instantly limiting the viability of others. Of…
Walking the Talk: Putting Constructivist Thinking into Practice in Classrooms.
ERIC Educational Resources Information Center
Riley, Maureen Keohane; And Others
1993-01-01
The constructivist approach of the Teacher as Composer project used analog experiences that replicate thinking and social demands. Classroom constraints, inservice limitations, and teacher mindsets impeded its application. Personal narratives and principles of children's thinking helped bridge the gap between theory and practice. (SK)
Gender Differences in the Perception of Administrative Role Demands.
ERIC Educational Resources Information Center
Estler, Suzanne E.
Efforts to understand the relationship between gender and school administration have usually focused on explaining the limited numbers of women administrators. Explanations of leadership style differences have stressed sex-role socialization theory, though some researchers suggest that the structure of power, opportunity, and social proportions in…
The impact of urban spatial structure on travel demand in the United States
DOT National Transportation Integrated Search
2003-03-20
Attempts to limit urban growth or to change its form are motivated by three concerns-to preserve open space and foster urban development that is more aesthetically appealing, to reduce the cost of providing public services, and to reduce dependence o...
ERIC Educational Resources Information Center
Bal, Vidula; Campbell, Michael; McDowell-Larsen, Sharon
2008-01-01
Everyone experiences stress, and leaders face the additional stress brought about by the unique demands of leadership: having to make decisions with limited information, to manage conflict, to do more with less ...and faster! The consequences of stress can include health problems and deteriorating relationships. Knowing what signs of stress to…
The Many-Headed Hydra: Information Networking at LAA.
ERIC Educational Resources Information Center
Winzenried, Arthur P.
1997-01-01
Describes an integrated computer library system installed at Lilydale Adventist Academy (LAA) in Melbourne (Australia) in response to a limited budget, increased demand, and greater user expectations. Topics include student workstations, cost effectiveness, CD-ROMS on local area networks, and student input regarding their needs. (Author/LRW)
77 FR 45653 - Lemon Juice From Argentina and Mexico
Federal Register 2010, 2011, 2012, 2013, 2014
2012-08-01
... significant changes, if any, in the supply and demand conditions or business cycle for the Domestic Like..., Deputy Agency Ethics Official, at 202-205-3088. Limited disclosure of business proprietary information... trade/business association; import/export Subject Merchandise from more than one Subject Country; or...
76 FR 168 - Heavy Forged Hand Tools From China
Federal Register 2010, 2011, 2012, 2013, 2014
2011-01-03
.... (12) Identify significant changes, if any, in the supply and demand conditions or business cycle for..., Deputy Agency Ethics Official, at 202-205-3088. Limited disclosure of business proprietary information... Subject Merchandise, a U.S. or foreign trade or business association, or another interested party...
76 FR 11268 - Certain Polyester Staple Fiber From Korea and Taiwan
Federal Register 2010, 2011, 2012, 2013, 2014
2011-03-01
.... (12) Identify significant changes, if any, in the supply and demand conditions or business cycle for..., Deputy Agency Ethics Official, at 202-205-3088. Limited disclosure of business proprietary information... domestic producer, union/worker group, or trade/business association; import/export Subject Merchandise...
32 CFR 725.7 - Contents of a proper request or demand.
Code of Federal Regulations, 2010 CFR
2010-07-01
... the oral request including the grant or denial, circumstances requiring the procedure, and conditions... by the limits of the oral grant, partial grant, or denial. ... correct the deposition at no cost to the witness or the Government; (8) A statement of understanding that...
Survey evidence on the importance of fuel availability to choice of alternative fuels and vehicles
DOT National Transportation Integrated Search
1997-11-11
The effect of limited fuel availability on the demand for alternative fuels and : vehicles is a critical factor in the transition to alternative fuels. Because : petroleum fuels have been so dominant for so long, the relationship between fuel : avail...
The World through an Interdisciplinary Lens
ERIC Educational Resources Information Center
Poulos, Helen; Bannon, Bryan; Isard, Jeremy; Stonebraker, Phoebe; Royer, Dana; Yohe, Gary; Chernoff, Barry
2012-01-01
Scholars and teachers have long struggled to respond to the growing demand for interdisciplinary approaches to complex social issues. They come to the table with their own disciplinary perspectives (scholars more rigidly than students, perhaps), but they also recognize the limitations of investigating social issues through a single disciplinary…
Genetics, breeding and selection of rootstocks for Solanaceae and Cucurbitaceae
USDA-ARS?s Scientific Manuscript database
Limited availability of arable land and high market demand for off-season vegetables often leads to continuous cultivation and cultivation under unfavorable conditions such as too cold, wet, dry, or under low-light winter greenhouses. Successive cropping can increase salinity, the incidence of vege...
48 CFR 27.102 - General guidance.
Code of Federal Regulations, 2010 CFR
2010-10-01
...) The Government recognizes rights in data developed at private expense, and limits its demands for delivery of that data. When such data is delivered, the Government will acquire only those rights essential... copyright owners before including copyrighted works, owned by others, in data to be delivered to the...
USDA-ARS?s Scientific Manuscript database
Hydrologic models are essential tools for environmental assessment of agricultural non-point source pollution. The automatic calibration of hydrologic models, though efficient, demands significant computational power, which can limit its application. The study objective was to investigate a cost e...
Srivastava, Divya; McGuire, Alistair
2014-07-30
Access to medicines is an important health policy issue. This paper considers demand structures in a selection of low-income countries from the perspective of public authorities as the evidence base is limited. Analysis of the demand for medicines in low-income countries is critical for effective pharmaceutical policy where regulation is less developed, health systems are cash constrained and medicines are not typically subsidised by a public health insurance system This study analyses the demand for medicines in low-income countries from the perspective of the prices paid by public authorities. The analysis draws on a unique dataset from World Health Organization (WHO) and Health Action International (HAI) using 2003 data on procurement prices of medicines across 16 low-income countries covering 48 branded drugs and 18 therapeutic categories. Variation in prices, the mark-ups over marginal costs and estimation of price elasticities allows assessment of whether these elasticities are correlated with a country's national income. Using the Ramsey pricing rule, the study's findings suggest that substantial cross-country variation in prices and mark-ups exist, with price elasticities ranging from -1 to -2, which are weakly correlated with national income. Government demand for medicines thus appears to be price elastic, raising important policy implications aimed at improving access to medicines for patients in low-income countries.
Bacillus Calmette-Guérin (BCG) vaccine: A global assessment of demand and supply balance.
Cernuschi, Tania; Malvolti, Stefano; Nickels, Emily; Friede, Martin
2018-01-25
Over the past decade, several countries across all regions, income groups and procurement methods have been unable to secure sufficient BCG vaccine supply. While the frequency of stock-outs has remained rather stable, duration increased in 2014-2015 due to manufacturing issues and attracted the attention of national, regional and global immunization stakeholders. This prompted an in-depth analysis of supply and demand dynamics aiming to characterize supply risks. This analysis is unique as it provides a global picture, where previous analyses have focused on a portion of the market procuring through UN entities. Through literature review, supplier interviews, appraisal of shortages, stock-outs and historical procurement data, and through demand forecasting, this analysis shows an important increase in global capacity in 2017: supply is sufficient to meet forecasted BCG vaccine demand and possibly buffer market shocks. Nevertheless, risks remain mainly due to supply concentration and limited investment in production process improvements, as well as inflexibility in demand. Identification of these market risks will allow implementation of risk-mitigating interventions in three areas: (1) enhancing information sharing between major global health actors, countries and suppliers, (2) identifying interests and incentives to expand product registration and investment in the BCG manufacturing process, and (3) working with countries for tighter vaccine management. Copyright © 2017. Published by Elsevier Ltd.
Soucy, Kevin G; Bartoli, Carlo R; Phillips, Dustin; Giridharan, Guruprasad A; Sobieski, Michael A; Wead, William B; Dowling, Robert D; Wu, Zhongjun J; Prabhu, Sumanth D; Slaughter, Mark S; Koenig, Steven C
2017-06-01
Continuous-flow left ventricular assist devices (CF LVADs) are rotary blood pumps that improve mean blood flow, but with potential limitations of non-physiological ventricular volume unloading and diminished vascular pulsatility. In this study, we tested the hypothesis that left ventricular unloading with increasing CF LVAD flow increases myocardial flow normalized to left ventricular work. Healthy (n = 8) and chronic ischemic heart failure (IHF, n = 7) calves were implanted with CF LVADs. Acute hemodynamics and regional myocardial blood flow were measured during baseline (LVAD off, clamped), partial (2-4 L/min) and full (>4 L/min) LVAD support. IHF calves demonstrated greater reduction of cardiac energy demand with increasing LVAD support compared to healthy calves, as calculated by rate-pressure product. Coronary artery flows (p < 0.05) and myocardial blood flow (left ventricle (LV) epicardium and myocardium, p < 0.05) decreased with increasing LVAD support in normal calves. In the IHF model, blood flow to the septum, LV, LV epicardium, and LV myocardium increased significantly with increasing LVAD support when normalized to cardiac energy demand (p < 0.05). In conclusion, myocardial blood flow relative to cardiac demand significantly increased in IHF calves, thereby demonstrating that CF LVAD unloading effectively improves cardiac supply and demand ratio in the setting of ischemic heart failure.
Thermal and digestive constraints to foraging behaviour in marine mammals.
Rosen, David A S; Winship, Arliss J; Hoopes, Lisa A
2007-11-29
While foraging models of terrestrial mammals are concerned primarily with optimizing time/energy budgets, models of foraging behaviour in marine mammals have been primarily concerned with physiological constraints. This has historically centred on calculations of aerobic dive limits. However, other physiological limits are key to forming foraging behaviour, including digestive limitations to food intake and thermoregulation. The ability of an animal to consume sufficient prey to meet its energy requirements is partly determined by its ability to acquire prey (limited by available foraging time, diving capabilities and thermoregulatory costs) and process that prey (limited by maximum digestion capacity and the time devoted to digestion). Failure to consume sufficient prey will have feedback effects on foraging, thermoregulation and digestive capacity through several interacting avenues. Energy deficits will be met through catabolism of tissues, principally the hypodermal lipid layer. Depletion of this blubber layer can affect both buoyancy and gait, increasing the costs and decreasing the efficiency of subsequent foraging attempts. Depletion of the insulative blubber layer may also increase thermoregulatory costs, which will decrease the foraging abilities through higher metabolic overheads. Thus, an energy deficit may lead to a downward spiral of increased tissue catabolism to pay for increased energy costs. Conversely, the heat generated through digestion and foraging activity may help to offset thermoregulatory costs. Finally, the circulatory demands of diving, thermoregulation and digestion may be mutually incompatible. This may force animals to alter time budgets to balance these exclusive demands. Analysis of these interacting processes will lead to a greater understanding of the physiological constraints within which the foraging behaviour must operate.
Mangham‐Jefferies, Lindsay; Gomez, Gabriela B.; Pitt, Catherine; Foster, Nicola
2016-01-01
Abstract Global guidelines for new technologies are based on cost and efficacy data from a limited number of trial locations. Country‐level decision makers need to consider whether cost‐effectiveness analysis used to inform global guidelines are sufficient for their situation or whether to use models that adjust cost‐effectiveness results taking into account setting‐specific epidemiological and cost heterogeneity. However, demand and supply constraints will also impact cost‐effectiveness by influencing the standard of care and the use and implementation of any new technology. These constraints may also vary substantially by setting. We present two case studies of economic evaluations of the introduction of new diagnostics for malaria and tuberculosis control. These case studies are used to analyse how the scope of economic evaluations of each technology expanded to account for and then address demand and supply constraints over time. We use these case studies to inform a conceptual framework that can be used to explore the characteristics of intervention complexity and the influence of demand and supply constraints. Finally, we describe a number of feasible steps that researchers who wish to apply our framework in cost‐effectiveness analyses. PMID:26786617
Moderating diets to feed the future
NASA Astrophysics Data System (ADS)
Davis, Kyle F.; D'Odorico, Paolo; Rulli, Maria Cristina
2014-10-01
Population growth, dietary changes, and increasing biofuel use are placing unprecedented pressure on the global food system. While this demand likely cannot be met by expanding agricultural lands, much of the world's cropland can attain higher crop yields. Therefore, it is important to examine whether increasing crop productivity to the maximum attainable yield (i.e., yield gap closure) alone can substantially improve food security at global and national scales. Here we show that closing yield gaps through conventional technological development (i.e., fertilizers and irrigation) can potentially meet future global demand if diets are moderated and crop-based biofuel production is limited. In particular, we find that increases in dietary demand will be largely to blame should crop production fall short of demand. In converting projected diets to a globally adequate diet (3000 kcal/cap/d; 20% animal kcal) under current agrofuel use, we find that 1.8-2.6 billion additional people can be fed in 2030 and 2.1-3.1 billion additional people in 2050, depending on the extent to which yields can improve in those periods. Therefore, the simple combination of yield gap closure and moderating diets offers promise for feeding the world's population but only if long-term sustainability is the focus.
Mendel, Peter; Nunes, Francisco; Wiig, Siri; van den Bovenkamp, Hester; Karltun, Anette; Robert, Glenn; Anderson, Janet; Vincent, Charles; Fulop, Naomi
2015-01-01
Objectives Given the impact of the global economic crisis, delivering better health care with limited finance grows more challenging. Through the lens of institutional theory, this paper explores pressures experienced by hospital leaders to improve quality and constrain spending, focusing on how they respond to these often competing demands. Methods An in-depth, multilevel analysis of health care quality policies and practices in five European countries including longitudinal case studies in a purposive sample of ten hospitals. Results How hospitals responded to the financial and quality challenges was dependent upon three factors: the coherence of demands from external institutions; managerial competence to align external demands with an overall quality improvement strategy, and managerial stability. Hospital leaders used diverse strategies and practices to manage conflicting external pressures. Conclusions The development of hospital leaders’ skills in translating external requirements into implementation plans with internal support is a complex, but crucial, task, if quality is to remain a priority during times of austerity. Increasing quality improvement skills within a hospital, developing a culture where quality improvement becomes embedded and linking cost reduction measures to improving care are all required. PMID:26683885
The production of information in the attention economy
Ciampaglia, Giovanni Luca; Flammini, Alessandro; Menczer, Filippo
2015-01-01
Online traces of human activity offer novel opportunities to study the dynamics of complex knowledge exchange networks, in particular how emergent patterns of collective attention determine what new information is generated and consumed. Can we measure the relationship between demand and supply for new information about a topic? We propose a normalization method to compare attention bursts statistics across topics with heterogeneous distribution of attention. Through analysis of a massive dataset on traffic to Wikipedia, we find that the production of new knowledge is associated to significant shifts of collective attention, which we take as proxy for its demand. This is consistent with a scenario in which allocation of attention toward a topic stimulates the demand for information about it, and in turn the supply of further novel information. However, attention spikes only for a limited time span, during which new content has higher chances of receiving traffic, compared to content created later or earlier on. Our attempt to quantify demand and supply of information, and our finding about their temporal ordering, may lead to the development of the fundamental laws of the attention economy, and to a better understanding of social exchange of knowledge information networks. PMID:25989177
NASA Astrophysics Data System (ADS)
Sidi, P.; Mamat, M.; Sukono; Supian, S.
2017-01-01
Floods have always occurred in the Citarum river basin. The adverse effects caused by floods can cover all their property, including the destruction of houses. The impact due to damage to residential buildings is usually not small. Indeed, each of flooding, the government and several social organizations providing funds to repair the building. But the donations are given very limited, so it cannot cover the entire cost of repair was necessary. The presence of insurance products for property damage caused by the floods is considered very important. However, if its presence is also considered necessary by the public or not? In this paper, the factors that affect the supply and demand of insurance product for damaged building due to floods are analyzed. The method used in this analysis is the ordinal logistic regression. Based on the analysis that the factors that affect the supply and demand of insurance product for damaged building due to floods, it is included: age, economic circumstances, family situations, insurance motivations, and lifestyle. Simultaneously that the factors affecting supply and demand of insurance product for damaged building due to floods mounted to 65.7%.
NASA Astrophysics Data System (ADS)
Bando, Shigeru; Watanabe, Hiroki; Asano, Hiroshi; Tsujita, Shinsuke
A methodology was developed to design the number and capacity for each piece of equipment (e.g. gas engines, batteries, thermal storage tanks) in microgrids with combined heat and power systems. We analyzed three types of microgrids; the first one consists of an office building and an apartment, the second one consists of a hospital and an apartment, the third one consists of a hotel, office and retails. In the methodology, annual cost is minimized by considering the partial load efficiency of a gas engine and its scale economy, and the optimal number and capacity of each piece of equipment and the annual operational schedule are determined by using the optimal planning method. Based on calculations using this design methodology, it is found that the optimal number of gas engines is determined by the ratio of bottom to peak of the electricity demand and the ratio of heat to electricity demand. The optimal capacity of a battery required to supply electricity for a limited time during a peak demand period is auxiliary. The thermal storage tank for space cooling and space heating is selected to minimize the use of auxiliary equipment such as a gas absorption chiller.
Time series modelling and forecasting of emergency department overcrowding.
Kadri, Farid; Harrou, Fouzi; Chaabane, Sondès; Tahon, Christian
2014-09-01
Efficient management of patient flow (demand) in emergency departments (EDs) has become an urgent issue for many hospital administrations. Today, more and more attention is being paid to hospital management systems to optimally manage patient flow and to improve management strategies, efficiency and safety in such establishments. To this end, EDs require significant human and material resources, but unfortunately these are limited. Within such a framework, the ability to accurately forecast demand in emergency departments has considerable implications for hospitals to improve resource allocation and strategic planning. The aim of this study was to develop models for forecasting daily attendances at the hospital emergency department in Lille, France. The study demonstrates how time-series analysis can be used to forecast, at least in the short term, demand for emergency services in a hospital emergency department. The forecasts were based on daily patient attendances at the paediatric emergency department in Lille regional hospital centre, France, from January 2012 to December 2012. An autoregressive integrated moving average (ARIMA) method was applied separately to each of the two GEMSA categories and total patient attendances. Time-series analysis was shown to provide a useful, readily available tool for forecasting emergency department demand.
Belke, Terry W; Pierce, W David
2009-02-01
Twelve female Long-Evans rats were exposed to concurrent variable (VR) ratio schedules of sucrose and wheel-running reinforcement (Sucrose VR 10 Wheel VR 10; Sucrose VR 5 Wheel VR 20; Sucrose VR 20 Wheel VR 5) with predetermined budgets (number of responses). The allocation of lever pressing to the sucrose and wheel-running alternatives was assessed at high and low body weights. Results showed that wheel-running rate and lever-pressing rates for sucrose and wheel running increased, but the choice of wheel running decreased at the low body weight. A regression analysis of relative consumption as a function of relative price showed that consumption shifted toward sucrose and interacted with price differences in a manner consistent with increased substitutability. Demand curves showed that demand for sucrose became less elastic while demand for wheel running became more elastic at the low body weight. These findings reflect an increase in the difference in relative value of sucrose and wheel running as body weight decreased. Discussion focuses on the limitations of response rates as measures of reinforcement value. In addition, we address the commonalities between matching and demand curve equations for the analysis of changes in relative reinforcement value.
Burnett, Susan; Mendel, Peter; Nunes, Francisco; Wiig, Siri; van den Bovenkamp, Hester; Karltun, Anette; Robert, Glenn; Anderson, Janet; Vincent, Charles; Fulop, Naomi
2016-04-01
Given the impact of the global economic crisis, delivering better health care with limited finance grows more challenging. Through the lens of institutional theory, this paper explores pressures experienced by hospital leaders to improve quality and constrain spending, focusing on how they respond to these often competing demands. An in-depth, multilevel analysis of health care quality policies and practices in five European countries including longitudinal case studies in a purposive sample of ten hospitals. How hospitals responded to the financial and quality challenges was dependent upon three factors: the coherence of demands from external institutions; managerial competence to align external demands with an overall quality improvement strategy, and managerial stability. Hospital leaders used diverse strategies and practices to manage conflicting external pressures. The development of hospital leaders' skills in translating external requirements into implementation plans with internal support is a complex, but crucial, task, if quality is to remain a priority during times of austerity. Increasing quality improvement skills within a hospital, developing a culture where quality improvement becomes embedded and linking cost reduction measures to improving care are all required. © The Author(s) 2015.
Ecology and equity: key determinants of sustainable water security.
Swaminathan, M S
2001-01-01
Trends in water consumption indicate that demand for water for household and industrial uses in developing countries could double as a proportion of total water demand in the next 25 years. Scope for expansion of water supply will, at the same time, be limited because development of irrigation and urban water supplies is becoming increasingly expensive, and often involves high costs in terms of environmental degradation and human resettlement. Without fundamental reform of water management, the rapid growth in urban water demand will require large transfers of water from irrigated agriculture, thereby threatening food security. Hence, water supply and demand should be managed in an integrated fashion, simultaneously considering all uses and sources. This will call for the establishment of community centred food and water security systems and national water trusts. Once such systems and Trusts are established there could be a legally binding Global Water Convention on the model of the Global Convention on Climate and Biodiversity. The details of such a Global Water Conventions can be finalized at one of the future Stockholm Water Symposia. There are uncommon opportunities today for a water-secure world through synergy between technology, public policy and peoples' participation.
Policies to Enhance Prescribing Efficiency in Europe: Findings and Future Implications
Godman, Brian; Shrank, William; Andersen, Morten; Berg, Christian; Bishop, Iain; Burkhardt, Thomas; Garuoliene, Kristina; Herholz, Harald; Joppi, Roberta; Kalaba, Marija; Laius, Ott; Lonsdale, Julie; Malmström, Rickard E.; Martikainen, Jaana E.; Samaluk, Vita; Sermet, Catherine; Schwabe, Ulrich; Teixeira, Inês; Tilson, Lesley; Tulunay, F. Cankat; Vlahović-Palčevski, Vera; Wendykowska, Kamila; Wettermark, Bjorn; Zara, Corinne; Gustafsson, Lars L.
2010-01-01
Introduction: European countries need to learn from each other to address unsustainable increases in pharmaceutical expenditures. Objective: To assess the influence of the many supply and demand-side initiatives introduced across Europe to enhance prescribing efficiency in ambulatory care. As a result provide future guidance to countries. Methods: Cross national retrospective observational study of utilization (DDDs – defined daily doses) and expenditure (Euros and local currency) of proton pump inhibitors (PPIs) and statins among 19 European countries and regions principally from 2001 to 2007. Demand-side measures categorized under the “4Es” – education engineering, economics, and enforcement. Results: Instigating supply side initiatives to lower the price of generics combined with demand-side measures to enhance their prescribing is important to maximize prescribing efficiency. Just addressing one component will limit potential efficiency gains. The influence of demand-side reforms appears additive, with multiple initiatives typically having a greater influence on increasing prescribing efficiency than single measures apart from potentially “enforcement.” There are also appreciable differences in expenditure (€/1000 inhabitants/year) between countries. Countries that have not introduced multiple demand side measures to counteract commercial pressures to enhance the prescribing of generics have seen considerably higher expenditures than those that have instigated a range of measures. Conclusions: There are considerable opportunities for European countries to enhance their prescribing efficiency, with countries already learning from each other. The 4E methodology allows European countries to concisely capture the range of current demand-side measures and plan for the future knowing that initiatives can be additive to further enhance their prescribing efficiency. PMID:21833180
Analysing water use patterns for demand management: the case of the city of Masvingo, Zimbabwe
NASA Astrophysics Data System (ADS)
Dube, Emmanuel; van der Zaag, Pieter
Water use in urban centres is dynamic, fluctuates, differs between high and low-income users, and tends to increase over time. Supply infrastructure can often hardly keep pace with increased water consumption. Given (a) the high cost of infrastructure development, (b) the recent emphasis on demand management, and (c) the social obligation to provide water services to the poor, urban water providers are faced with an important choice: whether to go the demand management route, or to continue constructing new infrastructure. This paper sheds light on some of the possibilities and constraints of both choices by providing a case study of the city of Masvingo in Zimbabwe. The paper analyses water use patterns in this city with a population of 70,000, located in a drought prone region of average rainfall of 600 mm/a. Water consumption has reached the limits of the water supply capacity. The paper first looks at the long-term water use pattern of the city as a whole and the factors that have caused the observed pattern using multiple linear regression. The paper then analyses the patterns of water use of rich and poor households, and attempts to assess the (im)possibilities of influencing these by means of an appropriate tariff structure. In projecting future demand, the paper then considers a number of interventions that could influence demand, which include leakage control, pressure management, awareness campaigns, free technical advice to water users, as well as a new tariff structure. It also discusses when new supply infrastructure should be available, depending on the various demand management measures taken.
Orens, Douglas K; Chatburn, Robert L; Volsko, Teresa A; Stoller, James K
2007-12-01
The 2005 American Association for Respiratory Care Human Resources Survey suggested that the national demand for respiratory therapists (RTs) exceeds the supply. At the Cleveland Clinic an expected hospital expansion of 350 beds by 2008 has increased the need for RT staff. This report describes a strategy by which we developed a plan, in concert with local RT colleges, to recruit RTs. Local RT managers were surveyed regarding demand for RTs. We developed a recruitment plan, based on discussions with RT program directors. The survey data and models estimated an annual mean of 33.4 new positions in northeast Ohio. Despite the fact that approximately 84 people graduated from northeast Ohio RT programs yearly in 2004 to 2007, the growth in demand for RTs exceeded the estimated supply. The main factor that caused RT schools to limit the supply of RTs was the paucity of clinical sites. Our analysis shows the schools could achieve a 40% increase in student output, and that if the Cleveland Clinic could essentially double its graduate hires, all RT staff needs in our hospital would be met by 2010. To assure a needed supply of RTs, this work shows the value of modeling supply and demand scenarios, coupled with surveying local RT leaders and fostering dialog between local RT leaders in hospitals and colleges. The product of this activity was a strategy for achieving recruitment goals while assuring that other regional demands for RTs are also met. We recommend this approach to colleagues facing similar challenges.
ERIC Educational Resources Information Center
Hall, Ralph L.
The game of chess is recommended as a school activity. In addition to requiring that individuals become actively involved in a mentally demanding competition, its effects are stimulating, wholesome, and healthy. Several benefits accrue from the teaching and promoting of chess in schools. Chess limits the element of luck (teaching the importance of…
Differences in creosotebush (Larrea tridentata) crown morphology may reflect changes in the relative demand for water vs. nutrient resources, coinciding with shrub growth and development Creosotebushes with inverted cone-shaped crowns were more abundant in water-limited environme...
Utilizing Online Training for Child Sexual Abuse Prevention: Benefits and Limitations
ERIC Educational Resources Information Center
Paranal, Rechelle; Thomas, Kiona Washington; Derrick, Christina
2012-01-01
The prevalence of child sexual abuse demands innovative approaches to prevent further victimization. The online environment provides new opportunities to expand existing child sexual abuse prevention trainings that target adult gatekeepers and allow for large scale interventions that are fiscally viable. This article discusses the benefits and…
USDA-ARS?s Scientific Manuscript database
The anti-parasitic, anti-cancer, and anti-viral sesquiterpene lactone artemisinin, commercially extracted from Artemisia annua, is in high demand worldwide. However, limited information is available on how post-harvest drying procedures affect plant biochemistry leading to the biosynthesis of artem...
Leadership Accountability Models: Issues of Policy and Practice.
ERIC Educational Resources Information Center
Wallace, Stephen O.; Sweatt, Owen; Acker-Hocevar, Michele
This paper explores two questions: "What philosophical views of educational leadership will adequately allow us to meet the demands of a rapidly changing world?" and "How should such leadership be assessed?" The article asserts that evaluation of educational leadership needs to break away from the limitations of restrictive models to become…
The Use of GBL to Teach Mathematics in Higher Education
ERIC Educational Resources Information Center
Naik, Nitin
2017-01-01
Innovation in learning and teaching is an everyday requirement in contemporary higher education (HE), especially in challenging subjects such as mathematics. Teaching mathematics to students with limited experience of formal mathematical instruction is a good example of a demanding pedagogical undertaking where innovatory practice can help HE…
Feasibility and Preliminary Outcomes of a Yoga and Mindfulness Intervention for School Teachers
ERIC Educational Resources Information Center
Ancona, Matthew R.; Mendelson, Tamar
2014-01-01
Many public school teachers face formidable challenges, including overcrowded classrooms, limited administrative resources, and high numbers of students with behavioral and emotional problems. Mindfulness-based strategies are a potentially promising means of reducing teachers' stress and enhancing their ability to handle job demands effectively.…
How Much Is a President Worth?
ERIC Educational Resources Information Center
Trachtenberg, Stephen Joel
2007-01-01
Finding an appropriate policy for setting presidents' pay is elusive, given the dubious nature of salary comparisons. In this article, the author suggests that trustees should determine the president's worth by considering the institution's interests, the limited talent pool, and the multiple demands of the job. He contends that institutions…
Rooting Rose Cuttings in Whole Pine Tree Substrates
USDA-ARS?s Scientific Manuscript database
Increased demand for alternatives to pine bark (PB) and peat moss (P) has led to extensive research on wood-based substrates, such as processed whole pine trees (WPT), for nursery and greenhouse crop production. Limited information is available on how WPT may perform as a rooting substrate for cutti...
Fiscal Stress: Worldwide Trends in Higher Education Finance
ERIC Educational Resources Information Center
Vossensteyn, Hans
2004-01-01
While higher education is generally a high priority in boosting economic development, public budgets to sustain expansion of higher education systems remain limited around the globe. This fiscal stress creates an impetus for governments to develop various strategies to meet the growing demand--from both students and society--for higher education…
Utilization of biofuel production residuals for food applications
USDA-ARS?s Scientific Manuscript database
Recent increase in biofuel production creates a sizable stockpile of its co-product – non-fermentable grain kernel components such as proteins, fibers, and lipids, in the form of Distiller’s Dried Grain with Solubles (DDGS) that has found limited uses in animal feeds. The market demand for DDGS in ...
Increasing the Efficiency of the One Room School.
ERIC Educational Resources Information Center
Berg, Paul
The one room school is a challenging educational setting for both teacher and student. Isolation of the school, limited availability of educational resources, and the demanding role of the school as the only formal educational institution within the community are conditions which make classroom efficiency an important consideration for the…
NITROGEN LOSS FROM SMALL WATERSHEDS IN THE OREGON CASCADES: A STUDY OF FOREST SUCCESSION INFLUENCE
Traditional biogeochemical theory suggests that biotic N limitation (N demand by plants and soil microorganisms) controls ecosystem nitrogen (N) losses, and that stream N export should increase with successional age. I am examining patterns of inorganic and organic N export from...
Chinese Students' Perception of Out-of-Class Groupwork in Australia
ERIC Educational Resources Information Center
Li, Dongmei; Remedios, Louisa; Clarke, David
2010-01-01
Despite increasing number of mainland Chinese students studying in western tertiary settings, there is limited information available on their learning experiences and responses to popular educational practices in these contexts. There is an assumption in the literature that Chinese students respond well to the collaborative demands of groupwork…
The Second Workforce--Female Employees
ERIC Educational Resources Information Center
Wilson, B.; Shorter, Barbara
1975-01-01
The British Oxygen Company Limited's Gases Division Study on the female workforce concluded: not enough use is made of female employee's skill and knowledge, the company shouldn't assume all women want careers but should help them realize the demands a career makes on their time, energy, and commitment. (Author/BP)
Water supply rates for recirculating evaporative cooling systems in poultry housing
USDA-ARS?s Scientific Manuscript database
Evaporative cooling (EC) is an important tool to reduce heat stress in animal housing systems. Expansion of ventilation capacity in tunnel ventilated poultry facilities has resulted in increased water demand for EC systems. As water resources become more limited and costly, proper planning and des...
77 FR 48476 - Proposed Amendment to Class B Airspace; Detroit, MI
Federal Register 2010, 2011, 2012, 2013, 2014
2012-08-14
... primary instrument approach configuration to meet demand at that time. These procedures today require that... approaches once again extended 5 to 10 miles beyond the lateral limits of today's Class B airspace design. In...-0661 and Airspace Docket No. 09-AWA-4.'' The [[Page 48477
Cellulosic ethanol production of forage sorghum under deficit irrigation
USDA-ARS?s Scientific Manuscript database
Recent emphasis on renewable energy sources has led to an increased demand for biofuel feedstocks. However, current production of biofuels such as ethanol (EtOH) utilizes food crops such as corn grain and sugarcane, which are typically cultivated on fertile soils that have few limits on plant growth...
Higher Learning in America: Aims and Realities.
ERIC Educational Resources Information Center
Reynolds, W. Ann
Although the realities of higher education accurately match the aims of early educators, there are limits to our ability to measure the learning that occurs in colleges and universities. As higher education has been made available to a greater quantity of participants, the demand for accountability has increased. Accountability concerns vary for…
A New Funding Model for Extension
ERIC Educational Resources Information Center
Brown, Paul W.; Otto, Daniel M.; Ouart, Michael D.
2006-01-01
The traditional funding model of the Cooperative Extension System has been stretched to its limits by increasing demand for information and programs without concurrent increases in funding by the public sector. As the social, economic, and political environments have evolved and become more complex, extension is often asked to apply the expertise…
Colliding Scopes: Seeing Academic Library Leadership through a Lens of Complexity
ERIC Educational Resources Information Center
Baird, Lynn N.
2010-01-01
Academic libraries routinely negotiate layers of change as embedded organizations in higher education institutions. Facing competing demands with limited resources gave rise to the question: how do academic library deans effectively lead their organizations in times of change? A Delphi Method study was conducted to identify successful leadership…
The Fessenden Honors in Engineering Program
ERIC Educational Resources Information Center
Giazzoni, Michael
2018-01-01
Developing honors opportunities for students in engineering programs can be difficult, and the experience at the University of Pittsburgh is no exception. Often these students' degree requirements are so demanding that their opportunities for participating in honors experiences are severely limited. In each of the two semesters of their freshman…
Motel DHW Retrofit--Dallas, Texas
NASA Technical Reports Server (NTRS)
1982-01-01
Solar-energy system designed to provide 65% of total domestic-hot-water (DHW) demands for 100-room motel in Dallas, Texas is subject of a report now available. System is retrofit, and storage-tank size was limited to 1,000 gallons (3,785 1) by size of room where it is located.
Sorghum response to foliar application of phosphorus and potassium with saline water irrigation
USDA-ARS?s Scientific Manuscript database
Increasing demand for fresh water resources for urban and industrial uses is leading to limited availability of better quality water for crop irrigation. Therefore, crop response to poor quality irrigation water (ex: saline water), and strategies to mitigate the negative effects of poor quality irri...
Forecasting Pell Program Applications Using Structural Aggregate Models.
ERIC Educational Resources Information Center
Cavin, Edward S.
1995-01-01
Demand for Pell Grant financial aid has become difficult to predict when using the current microsimulation model. This paper proposes an alternative model that uses aggregate data (based on individuals' microlevel decisions and macrodata on family incomes, college costs, and opportunity wages) and avoids some limitations of simple linear models.…
Library 2.0: Service for the Next-Generation Library
ERIC Educational Resources Information Center
Casey, Michael E.; Savastinuk, Laura C.
2006-01-01
Libraries are changing. Funding limits and customer demands are transforming staffing levels, service models, access to resources, and services to the public. Administrators and taxpayers are seeking more efficient ways of delivering services to achieve greater returns on financial investments. In this article, the author discusses the benefits of…
The Filipino Nursing Students' Dilemmas in Geriatric Care
ERIC Educational Resources Information Center
de Guzman, Allan B.; Cruz, Andrei Angelo R.; Cruz, Angela Laurice G.; Cruz, Robert Edward D.; Cuarto, Jose Mari Nino L.
2009-01-01
The continually rising percentage of the elderly population and the demand for geriatric nursing care are dramatically related. While it is true that most undergraduate programs prepare nurses for the care of geriatric patients, most receive limited academic preparation in the nursing curriculum (Williams & Mezey, 2000). This is particularly…
ERIC Educational Resources Information Center
Mayer, Caroline E.
2012-01-01
Given the stakes and the current economic climate, U.S. higher education officials across the country are stepping up their advocacy efforts, making their voices louder and more persistent than ever. They are vying for the attention of states struggling with increased demands for limited revenues, most choosing to divert dollars from higher…