Dynamic Analysis of Money Demand Function: Case of Turkey*

OpenAIRE

doğru, bülent

2013-01-01

In this paper, the dynamic determinants of money demand function and the long-run and short-run relationships between money demand, income and nominal interest rates are examined in Turkey for the time period 1980-2012. In particular we estimate a dynamic specification of a log money demand function based on Keynesian liquidity preference theory to ascertain the relevant elasticity of money demand. The empirical results of the study show that in Turkey inflation, exchange rate and money deman...

Bank Credit and Aggregate Import Demand in Nigeria: A Cointegration Analysis

Directory of Open Access Journals (Sweden)

Philip Chimobi Omoke

2012-06-01

Full Text Available This study reformulated the aggregate import demand for Nigeria by including a financial variable (bank credit into the traditional import demand function for the period 1970-2009. The Johansen Multivariate cointegration analysis was used to estimate the function. The result obtained from the study shows no evidence of the existence of cointegrating relations between bank credit and import demand. This shows that bank credit is found to be insufficient as a policy instrument for long term import demand in Nigeria. Thus, the financial variable should not be included in modelling the aggregate import demand for Nigeria.

Re-examining uranium supply and demand: New insights

International Nuclear Information System (INIS)

Kahouli, Sondes

2011-01-01

In this paper, we derive a simultaneous system of equations which aims at analysing the uranium supply and demand. In addition to reviewing and updating previous studies dealing with the uranium market analysis, in particular , the contribution of the paper lies in putting attention to some questions which are still either controversial or unanswered. They are especially related to the controversial hypothesis of the interdependence between uranium market and other commodities markets, both, with respect to the demand side, i.e. oil and coal markets, and the supply side, i.e. gold market. The paper also casts lights on electricity and uranium price effects on uranium demand as well as on the simultaneous interdependencies that may exist between nuclear consumption and nuclear installed capacity. The model is estimated for three different time periods which takes into account the major events that have influenced the nuclear-uranium development, that is, that have constrained the growth rate of nuclear generating capacity, i.e. oil crisis and nuclear accidents. This permits to show if uranium market reaction is independent or it is correlated with specific events associated with each time periods. The model was estimated by using the 3SLS method that correct for the presence of contemporaneously error terms correlation and for the existence of simultaneity bias in the model. Main results give evidence of significant correlation between uranium price and competing fossil fuel prices. They also point-out that uranium price is significantly correlated with the supply forces where supply is significantly dependent on gold prices. Moreover, results show that the electricity prices have a significant effect on the uranium demand only in the post-1990 period, probably following the worldwide electricity prices increasing trend. Further, our estimations show that uranium demand is significantly correlated with uranium price only in the period of nuclear major expansion. As

Re-examining uranium supply and demand: New insights

Energy Technology Data Exchange (ETDEWEB)

Kahouli, Sondes, E-mail: sondes.kahouli@univ-nantes.f [Universite de Nantes, Laboratoire d' Economie et de Management de Nantes Atlantique (LEMNA), Institut d' Economie et de Management de Nantes-I.A.E., Chemin de la Censive du Tertre-B.P. 52231, 44322 Nantes Cedex 3 (France)

2011-01-15

In this paper, we derive a simultaneous system of equations which aims at analysing the uranium supply and demand. In addition to reviewing and updating previous studies dealing with the uranium market analysis, in particular , the contribution of the paper lies in putting attention to some questions which are still either controversial or unanswered. They are especially related to the controversial hypothesis of the interdependence between uranium market and other commodities markets, both, with respect to the demand side, i.e. oil and coal markets, and the supply side, i.e. gold market. The paper also casts lights on electricity and uranium price effects on uranium demand as well as on the simultaneous interdependencies that may exist between nuclear consumption and nuclear installed capacity. The model is estimated for three different time periods which takes into account the major events that have influenced the nuclear-uranium development, that is, that have constrained the growth rate of nuclear generating capacity, i.e. oil crisis and nuclear accidents. This permits to show if uranium market reaction is independent or it is correlated with specific events associated with each time periods. The model was estimated by using the 3SLS method that correct for the presence of contemporaneously error terms correlation and for the existence of simultaneity bias in the model. Main results give evidence of significant correlation between uranium price and competing fossil fuel prices. They also point-out that uranium price is significantly correlated with the supply forces where supply is significantly dependent on gold prices. Moreover, results show that the electricity prices have a significant effect on the uranium demand only in the post-1990 period, probably following the worldwide electricity prices increasing trend. Further, our estimations show that uranium demand is significantly correlated with uranium price only in the period of nuclear major expansion. As

Re-examining uranium supply and demand. New insights

Energy Technology Data Exchange (ETDEWEB)

Kahouli, Sondes [Universite de Nantes, Laboratoire d' Economie et de Management de Nantes Atlantique (LEMNA), Institut d' Economie et de Management de Nantes - I.A.E., Chemin de la Censive du Tertre - B.P. 52231, 44322 Nantes Cedex 3 (France)

2011-01-15

In this paper, we derive a simultaneous system of equations which aims at analysing the uranium supply and demand. In addition to reviewing and updating previous studies dealing with the uranium market analysis, in particular, the contribution of the paper lies in putting attention to some questions which are still either controversial or unanswered. They are especially related to the controversial hypothesis of the interdependence between uranium market and other commodities markets, both, with respect to the demand side, i.e. oil and coal markets, and the supply side, i.e. gold market. The paper also casts lights on electricity and uranium price effects on uranium demand as well as on the simultaneous interdependencies that may exist between nuclear consumption and nuclear installed capacity. The model is estimated for three different time periods which takes into account the major events that have influenced the nuclear-uranium development, that is, that have constrained the growth rate of nuclear generating capacity, i.e. oil crisis and nuclear accidents. This permits to show if uranium market reaction is independent or it is correlated with specific events associated with each time periods. The model was estimated by using the 3SLS method that correct for the presence of contemporaneously error terms correlation and for the existence of simultaneity bias in the model. Main results give evidence of significant correlation between uranium price and competing fossil fuel prices. They also point-out that uranium price is significantly correlated with the supply forces where supply is significantly dependent on gold prices. Moreover, results show that the electricity prices have a significant effect on the uranium demand only in the post-1990 period, probably following the worldwide electricity prices increasing trend. Further, our estimations show that uranium demand is significantly correlated with uranium price only in the period of nuclear major expansion. As

Willingness to pay and price elasticities of demand for energy-efficient appliances: Combining the hedonic approach and demand systems

Energy Technology Data Exchange (ETDEWEB)

Galarraga, Ibon, E-mail: ibon.galarraga@bc3research.org; Gonzalez-Eguino, Mikel, E-mail: mikel.gonzalez@bc3research.org; Markandya, Anil, E-mail: anil.markandya@bc3research.org

2011-12-15

This article proposes a combined approach for estimating willingness to pay for the attributes represented by energy efficiency labels and providing reliable price elasticities of demand (own and cross) for close substitutes (e.g. those with low energy efficiency and those with higher energy efficiency). This is done by using the results of the hedonic approach together with the Quantity Based Demand System (QBDS) model. The elasticity results obtained with the latter are then compared with those simulated using the Linear Almost Ideal Demand System (LA/AIDS). The methodology is applied to the dishwasher market in Spain: it is found that 15.6% of the final price is actually paid for the energy efficiency attribute. This accounts for about Euro 80 of the average market price. The elasticity results confirm that energy efficient appliances are more price elastic than regular ones. - Highlights: > The article shows a combined approach for estimating willingness to pay for energy efficiency labels and price elasticities. > The results of the hedonic approach is used together with the Quantity Based Demand System (QBDS) model. > The elasticity results are compared with those simulated using the Linear Almost Ideal Demand System (LA/AIDS). > The methodology is applied to the dishwasher market in Spain.

Maintained benefits and improved survival of dynamic cardiomyoplasty by activity-rest stimulation: 5-year results of the Italian trial on "demand" dynamic cardiomyoplasty.

Science.gov (United States)

Rigatelli, Gianluca; Barbiero, Mario; Rigatelli, Giorgio; Riccardi, Roberto; Cobelli, Franco; Cotogni, Angelo; Bandello, Attilio; Carraro, Ugo

2003-01-01

Latissimus dorsi (LD) muscular degeneration caused by continuous electrical stimulation has been the main cause of the poor results of dynamic cardiomyoplasty (DCMP) and its exclusion from the recent international guidelines on heart failure. To avoid full transformation of the LD and to improve results, a new stimulation protocol was developed; fewer impulses per day are delivered, providing the LD wrap with daily periods of rest ("demand" stimulation), based on a heart rate cut-off. The aim of this work is to report the results at 5 years of follow-up of the Italian Trial of Demand Dynamic Cardiomyoplasty and to discuss their impact on the destiny of this type of cardiac assistance. Twelve patients with dilated myocardiopathy (M/F=11/1, mean age 58.2+/-5.8 years, sinus rhythm/atrial fibrillation=11/1) were submitted during the period 1993-1996 to DCMP and at different intervals to demand protocol. Clinical, echocardiographic, mechanographic and cardiac invasive assessments were scheduled before initiating the demand protocol and during the follow-up at 0, 6 and every 12 months. The mean duration of follow-up was 40.2+/-13.8 months (range 18-64). There were no perioperative deaths. The demand stimulation protocol showed a decrease in 5 years in New York Health Association (NYHA) class (3.17+/-0.38-1.67+/-0.77, P=0.0001), an improvement of left ventricular ejection fraction (22.6+/-4.38-32.0+/-7.0, Pactuarial survival of 83.3% (one patient was switched to heart transplantation programme due to clinical worsening and another one died of massive pulmonary embolism). Demand DCMP maintains over time LD muscular properties, enhances clinical benefits and improves survival of DCMP, thus reopening the debate whether this type of treatment should be considered in patients with end-stage heart failure.

Demand forecasting and information platform in tourism

Directory of Open Access Journals (Sweden)

Li Yue

2017-05-01

Full Text Available Information asymmetry and the bullwhip effect have been serious problems in the tourism supply chain. Based on platform theory, this paper established a mathematical model to explore the inner mechanism of a platform’s influence on stakeholders’ ability to forecast demand in tourism. Results showed that the variance of stakeholders’ demand predictions with a platform was smaller than the variance without a platform, which meant that a platform would improve predictions of demand for stakeholders. The higher information-processing ability of the platform also had other effects on demand forecasting. Research on the inner logic of the platform’s influence on stakeholders has important theoretical and realistic value. This area is worthy of further study.

Characteristics and trends of China's oil demand

Energy Technology Data Exchange (ETDEWEB)

Wang, Haibo

2010-09-15

Based on historical analysis of Chinese oil consumption from 1980 to 2008, the author develops an econometric modeling - Medium and Long-term Chinese Oil Demand Forecast Model. Results shows that, Chinese oil demand will be 632 MT in 2020 without consideration of substitutions, and the annual growth rate will be 4.2%, much slower than before. The demand ratio of diesel to gasoline will decline, while kerosene demand will grow faster. If new energy vehicles (NGV and electric vehicles, etc.) develop rapidly and industrial fuel-oil demand is substituted effectively, about 23 million tons of oil could be saved.

OECD (Organization of Economic Cooperation and Development) oil demand

International Nuclear Information System (INIS)

Huntington, H.G.

1993-01-01

Econometric response surfaces for nine different world oil models are estimated for aggregate oil demand with in the developed countries of the Organization of Economic Cooperation and Development (OECD). The estimates are based upon scenario results reported for the 1989-2010 period in a recent model comparison study. The response surface approach provides a parsimonious summary of model responses. It enables one to estimate long-run price elasticities directly rather than to infer such responses from 20-year cross-scenario results. It also shows more directly the significant effect of initial demand conditions (in 1988) on future oil demand growth. Due to the dynamic nature of the oil demand response, past prices exert a strongly positive effect on future oil demands in some models, but little or even negative effect in other models. On the basis of this finding, we urge demand modellers to be much more explicit about what their systems reveal about the extent of disequilibrium embedded in their model's starting oil demand conditions. (author)

Domestic demand for petroleum products in MENA countries

Energy Technology Data Exchange (ETDEWEB)

Bhattacharyya, Subhes C.; Blake, Andon [CEPMLP, Dundee University, Dundee DD1 4HN (United Kingdom)

2009-04-15

The purpose of this paper is to analyse the domestic demand for petroleum products in the Middle East and North African (MENA) countries employing a recent data series (1982-2005). Understanding the domestic demand of oil producing countries is important due to the existence of subsidised supply, loss of foreign exchange income and the environmental effects of oil use. The paper analyses the evolution of petroleum product demand in MENA and presents an econometric analysis of demand using a simple log-linear specification for four petroleum products, namely gasoline, diesel, kerosene and fuel oil. The study covers seven MENA countries, namely Algeria, Iran, Kuwait, Libya, Saudi Arabia, UAE and Qatar. The results show that demand has grown quite fast in these countries probably because the fuel price has been kept very low while income has risen fast and thus demand has grown fast. The gasoline demand model has performed better than other models in terms of producing expected signs for the parameters. The results for the kerosene model was the least satisfactory as most of the coefficients were found to be statistically insignificant. However, in terms of numerical results, this study compares well with other similar studies of the past. (author)

Domestic demand for petroleum products in MENA countries

International Nuclear Information System (INIS)

Bhattacharyya, Subhes C.; Blake, Andon

2009-01-01

The purpose of this paper is to analyse the domestic demand for petroleum products in the Middle East and North African (MENA) countries employing a recent data series (1982-2005). Understanding the domestic demand of oil producing countries is important due to the existence of subsidised supply, loss of foreign exchange income and the environmental effects of oil use. The paper analyses the evolution of petroleum product demand in MENA and presents an econometric analysis of demand using a simple log-linear specification for four petroleum products, namely gasoline, diesel, kerosene and fuel oil. The study covers seven MENA countries, namely Algeria, Iran, Kuwait, Libya, Saudi Arabia, UAE and Qatar. The results show that demand has grown quite fast in these countries probably because the fuel price has been kept very low while income has risen fast and thus demand has grown fast. The gasoline demand model has performed better than other models in terms of producing expected signs for the parameters. The results for the kerosene model was the least satisfactory as most of the coefficients were found to be statistically insignificant. However, in terms of numerical results, this study compares well with other similar studies of the past. (author)

Application of Job Demands-Resources model in research on relationships between job satisfaction, job resources, individual resources and job demands

OpenAIRE

Adrianna Potocka; Małgorzata Waszkowska

2013-01-01

Background: The aim of this study was to explore the relationships between job demands, job resourses, personal resourses and job satisfaction and to assess the usefulness of the Job Demands-Resources (JD-R) model in the explanation of these phenomena. Materials and Methods: The research was based on a sample of 500 social workers. The "Psychosocial Factors" and "Job satisfaction" questionnaires were used to test the hypothesis. Results: The results showed that job satisfaction increased with...

Measuring Money Demand Function in Pakistan

OpenAIRE

Hassan, Shahid; Ali, Umbreen; Dawood, Mamoon

2016-01-01

This study investigates the factors such as interest rate, GDP per capita, exchange rate, fiscal deficit, urban and rural population to determine money demand function for Pakistan over the period from 1972-2013. We use ARDL Bound Testing approach in order to test long run relation between money demand and its factors whereas both long and short run coefficients will be found using similar approach. The results show that real interest rate exerts significant and negative effect upon money dem...

The effect of perceived risks on the demand for vaccination: results from a discrete choice experiment.

Directory of Open Access Journals (Sweden)

Md Z Sadique

Full Text Available The demand for vaccination against infectious diseases involves a choice between vaccinating and not vaccinating, in which there is a trade-off between the benefits and costs of each option. The aim of this paper is to investigate these trade-offs and to estimate how the perceived prevalence and severity of both the disease against which the vaccine is given and any vaccine associated adverse events (VAAE might affect demand. A discrete choice experiment (DCE was used to elicit stated preferences from a representative sample of 369 U.K. mothers of children below 5 years of age, for three hypothetical vaccines. Cost was included as an attribute, which enabled estimation of the willingness to pay for different vaccines having differing levels of the probability of occurrence and severity of both the infection and VAAE. The results suggest that the severity of the health effects associated with both the diseases and VAAEs exert an important influence on the demand for vaccination, whereas the probability of these events occurring was not a significant predictor. This has important implications for public health policy, which has tended to focus on the probability of these health effects as the main influence on decision making. Our results also suggest that anticipated regrets about the consequences of making the wrong decision also exert an influence on demand.

Exploring energy consumption and demand in China

International Nuclear Information System (INIS)

Fan, Ying; Xia, Yan

2012-01-01

China has been experiencing industrialization and urbanization since reform and opening of its economy in 1978. Energy consumption in the country has featured issues such as a coal-dominated energy mix, low energy efficiency and high emissions. Thus, it is of great importance to explore the factors driving the increase in energy consumption in the past two decades and estimate the potential for decreasing energy demands in the future. In this paper a hybrid energy input–output model is used to decompose driving factors to identify how these factors impact changes in energy intensity. A modified RAS approach is applied to project energy requirements in a BAU scenario and an alternative scenario. The results show that energy input mix, industry structure and technology improvements have major influences on energy demand. Energy demand in China will continue to increase at a rapid rate if the economy develops as in the past decades, and is projected to reach 4.7 billion tce in 2020. However, the huge potential for a decrease cannot be neglected, since growth could be better by adjusting the energy mix and industrial structure and enhancing technology improvements. The total energy demand could be less than 4.0 billion tce in 2020. -- Highlights: ► In this paper a hybrid energy input–output model is used to decompose driving factors to China’s energy intensity change. ► A modified RAS approach is applied to project energy requirements in China. ► The results show that energy input mix, industry structure and technology improvements have major influences on energy demand. ► Energy demand in China will reach 4.7 billion ton in 2020 if the economy develops as in the past decades. ► There is a huge potential for a decrease of energy demand by adjusting the energy mix and industrial structure and enhancing technology improvements.

Scheduling Non-Preemptible Jobs to Minimize Peak Demand

Directory of Open Access Journals (Sweden)

Sean Yaw

2017-10-01

Full Text Available This paper examines an important problem in smart grid energy scheduling; peaks in power demand are proportionally more expensive to generate and provision for. The issue is exacerbated in local microgrids that do not benefit from the aggregate smoothing experienced by large grids. Demand-side scheduling can reduce these peaks by taking advantage of the fact that there is often flexibility in job start times. We focus attention on the case where the jobs are non-preemptible, meaning once started, they run to completion. The associated optimization problem is called the peak demand minimization problem, and has been previously shown to be NP-hard. Our results include an optimal fixed-parameter tractable algorithm, a polynomial-time approximation algorithm, as well as an effective heuristic that can also be used in an online setting of the problem. Simulation results show that these methods can reduce peak demand by up to 50% versus on-demand scheduling for household power jobs.

Energy supply and demand result in fiscal 1995 and a short-term prospect. Report submitted by the energy supply and demand trend investigation committee; 1995 nendo energy jukyu jisseki to tanki tenbo. Energy jukyu doko chosa iinkai hokoku

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-10-01

This paper describes the energy demand and supply result in fiscal 1995 and a short-term prospect. The business condition in Japan is regaining some brightness. While the net GDP growth has stayed at 0.9%, the domestic primary energy supply has increased by 2.9% and the final energy consumption by 3.2% over the previous year, respectively. The energy consumption has increased by 3.7% with the background of increase in production levels in the industrial department in material industries induced by external demand. The consumer department showed as high growth as 5.1% centering on household room heating due to cold winter. The business and transportation departments presented an increase of 2.2% and 2.4%, respectively. Sharp growth of 3.0% was shown in the net GDP during January through March, 1996, having the net GDP growth rate for fiscal 1995 escaped from zero growth that has lasted three years. The recovery of the domestic business condition is moving gradually centering on the consumer demand, wherein the point to be focused from now on is how much the recovery can compensate for decline in the public demand and reduction in the external demand. Attention is given on path of the business condition recovery and future trends in energy demand under the situation of risen consumption tax and deregulated oil business. 42 figs., 73 tabs.

Application of Job Demands-Resources model in research on relationships between job satisfaction, job resources, individual resources and job demands

Directory of Open Access Journals (Sweden)

Adrianna Potocka

2013-04-01

Full Text Available Background: The aim of this study was to explore the relationships between job demands, job resourses, personal resourses and job satisfaction and to assess the usefulness of the Job Demands-Resources (JD-R model in the explanation of these phenomena. Materials and Methods: The research was based on a sample of 500 social workers. The "Psychosocial Factors" and "Job satisfaction" questionnaires were used to test the hypothesis. Results: The results showed that job satisfaction increased with increasing job accessibility and personal resources (r = 0.44; r = 0.31; p < 0.05. The analysis of variance (ANOVA indicated that job resources and job demands [F(1.474 = 4.004; F(1.474 = 4.166; p < 0.05] were statistically significant sources of variation in job satisfaction. Moreover, interactions between job demands and job resources [F(3,474 = 2.748; p < 0.05], as well as between job demands and personal resources [F(3.474 = 3.021; p < 0.05] had a significant impact on job satisfaction. The post hoc tests showed that 1 in low job demands, but high job resources employees declared higher job satisfaction, than those who perceived them as medium (p = 0.0001 or low (p = 0.0157; 2 when the level of job demands was perceived as medium, employees with high personal resources declared significantly higher job satisfaction than those with low personal resources (p = 0.0001. Conclusion: The JD-R model can be used to investigate job satisfaction. Taking into account fundamental factors of this model, in organizational management there are possibilities of shaping job satisfaction among employees. Med Pr 2013;64(2:217–225

[Application of job demands-resources model in research on relationships between job satisfaction, job resources, individual resources and job demands].

Science.gov (United States)

Potocka, Adrianna; Waszkowska, Małgorzata

2013-01-01

The aim of this study was to explore the relationships between job demands, job resourses, personal resourses and job satisfaction and to assess the usefulness of the Job Demands-Resources (JD-R) model in the explanation of these phenomena. The research was based on a sample of 500 social workers. The "Psychosocial Factors" and "Job satisfaction" questionnaires were used to test the hypothesis. The results showed that job satisfaction increased with increasing job accessibility and personal resources (r = 0.44; r = 0.31; p job resources and job demands [F(1.474) = 4.004; F(1.474) = 4.166; p job satisfaction. Moreover, interactions between job demands and job resources [F(3,474) = 2.748; p job demands and personal resources [F(3.474) = 3.021; p job satisfaction. The post hoc tests showed that 1) in low job demands, but high job resources employees declared higher job satisfaction, than those who perceived them as medium (p = 0.0001) or low (p = 0.0157); 2) when the level of job demands was perceived as medium, employees with high personal resources declared significantly higher job satisfaction than those with low personal resources (p = 0.0001). The JD-R model can be used to investigate job satisfaction. Taking into account fundamental factors of this model, in organizational management there are possibilities of shaping job satisfaction among employees.

Demand elasticity of oil in Barbados

Energy Technology Data Exchange (ETDEWEB)

Moore, Alvon, E-mail: armoore@centralbank.org.bb [Economist, Central Bank of Barbados, Toms Adams Financial Centre, Bridgetown (Barbados)

2011-06-15

The importation of oil is a significant component of Barbados' imports, rising from 7% of imports in 1998 to over 20% in 2009. This increase has impacted greatly on the level of foreign reserves. As a price-taker, relying entirely on imported oil for our energy needs could prove a continuous drain on the economy. With a view to formulating an appropriate energy policy for Barbados, this paper analyses the demand for oil using monthly data from 1998 to 2009. The paper estimates the elasticities of demand for oil by employing single equation cointegration approach and comparing the results with countries that rely heavily on imported oil and whose policy objective are to alter their energy structure to rely less on imported oil. The results show that the demand for oil imports is price inelastic in the long run. The consumption of oil is responsive to past consumption, prices, income, electricity consumption and the number of appliances imported in the short-run. A policy framework to reduce the use of oil for electricity consumption via alternative energy sources should be considered and the taxation of oil imports given its elasticity is a good source of revenue. - Highlights: > Demand for oil is price inelastic in the long-run (-0.552). > The relationship between oil demand and income is insignificant in the long run. > As electricity consumption increases by 1%, the demand for oil rises by 1.43%. > Need to determine if investments in alternative sources can offset demand for oil. > Investment in alternative resources may be required before gains are realised.

Price, environment and security: Exploring multi-modal motivation in voluntary residential peak demand response

International Nuclear Information System (INIS)

Gyamfi, Samuel; Krumdieck, Susan

2011-01-01

Peak demand on electricity grids is a growing problem that increases costs and risks to supply security. Residential sector loads often contribute significantly to seasonal and daily peak demand. Demand response projects aim to manage peak demand by applying price signals and automated load shedding technologies. This research investigates voluntary load shedding in response to information about the security of supply, the emission profile and the cost of meeting critical peak demand in the customers' network. Customer willingness to change behaviour in response to this information was explored through mail-back survey. The diversified demand modelling method was used along with energy audit data to estimate the potential peak load reduction resulting from the voluntary demand response. A case study was conducted in a suburb of Christchurch, New Zealand, where electricity is the main source for water and space heating. On this network, all water heating cylinders have ripple-control technology and about 50% of the households subscribe to differential day/night pricing plan. The survey results show that the sensitivity to supply security is on par with price, with the emission sensitivity being slightly weaker. The modelling results show potential 10% reduction in critical peak load for aggregate voluntary demand response. - Highlights: → Multiple-factor behaviour intervention is necessarily for effective residential demand response. → Security signals can achieve result comparable to price. → The modelling results show potential 10% reduction in critical peak load for aggregate voluntary demand response. → New Zealand's energy policy should include innovation and development of VDR programmes and technologies.

Automation of energy demand forecasting

Science.gov (United States)

Siddique, Sanzad

Automation of energy demand forecasting saves time and effort by searching automatically for an appropriate model in a candidate model space without manual intervention. This thesis introduces a search-based approach that improves the performance of the model searching process for econometrics models. Further improvements in the accuracy of the energy demand forecasting are achieved by integrating nonlinear transformations within the models. This thesis introduces machine learning techniques that are capable of modeling such nonlinearity. Algorithms for learning domain knowledge from time series data using the machine learning methods are also presented. The novel search based approach and the machine learning models are tested with synthetic data as well as with natural gas and electricity demand signals. Experimental results show that the model searching technique is capable of finding an appropriate forecasting model. Further experimental results demonstrate an improved forecasting accuracy achieved by using the novel machine learning techniques introduced in this thesis. This thesis presents an analysis of how the machine learning techniques learn domain knowledge. The learned domain knowledge is used to improve the forecast accuracy.

Econometric Modeling: An Application to the Demand for Electricity ...

African Journals Online (AJOL)

The empirical results show an inverse relationship between real appliance purchase price, the real per capita income and the demand for electricity. Also the rate of population growth rate as a proxy for electricity consumers appears to be insignificant. This reveals the clear fact that the demand for electricity is greater than ...

Demand controlled ventilation for multi-family dwellings

DEFF Research Database (Denmark)

Mortensen, Dorthe Kragsig

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

Open Automated Demand Response for Small Commerical Buildings

Energy Technology Data Exchange (ETDEWEB)

Dudley, June Han; Piette, Mary Ann; Koch, Ed; Hennage, Dan

2009-05-01

This report characterizes small commercial buildings by market segments, systems and end-uses; develops a framework for identifying demand response (DR) enabling technologies and communication means; and reports on the design and development of a low-cost OpenADR enabling technology that delivers demand reductions as a percentage of the total predicted building peak electric demand. The results show that small offices, restaurants and retail buildings are the major contributors making up over one third of the small commercial peak demand. The majority of the small commercial buildings in California are located in southern inland areas and the central valley. Single-zone packaged units with manual and programmable thermostat controls make up the majority of heating ventilation and air conditioning (HVAC) systems for small commercial buildings with less than 200 kW peak electric demand. Fluorescent tubes with magnetic ballast and manual controls dominate this customer group's lighting systems. There are various ways, each with its pros and cons for a particular application, to communicate with these systems and three methods to enable automated DR in small commercial buildings using the Open Automated Demand Response (or OpenADR) communications infrastructure. Development of DR strategies must consider building characteristics, such as weather sensitivity and load variability, as well as system design (i.e. under-sizing, under-lighting, over-sizing, etc). Finally, field tests show that requesting demand reductions as a percentage of the total building predicted peak electric demand is feasible using the OpenADR infrastructure.

Monopoly models with time-varying demand function

Science.gov (United States)

Cavalli, Fausto; Naimzada, Ahmad

2018-05-01

We study a family of monopoly models for markets characterized by time-varying demand functions, in which a boundedly rational agent chooses output levels on the basis of a gradient adjustment mechanism. After presenting the model for a generic framework, we analytically study the case of cyclically alternating demand functions. We show that both the perturbation size and the agent's reactivity to profitability variation signals can have counterintuitive roles on the resulting period-2 cycles and on their stability. In particular, increasing the perturbation size can have both a destabilizing and a stabilizing effect on the resulting dynamics. Moreover, in contrast with the case of time-constant demand functions, the agent's reactivity is not just destabilizing, but can improve stability, too. This means that a less cautious behavior can provide better performance, both with respect to stability and to achieved profits. We show that, even if the decision mechanism is very simple and is not able to always provide the optimal production decisions, achieved profits are very close to those optimal. Finally, we show that in agreement with the existing empirical literature, the price series obtained simulating the proposed model exhibit a significant deviation from normality and large volatility, in particular when underlying deterministic dynamics become unstable and complex.

On energy demand

International Nuclear Information System (INIS)

Haefele, W.

1977-01-01

Since the energy crisis, a number of energy plans have been proposed, and almost all of these envisage some kind of energy demand adaptations or conservation measures, hoping thus to escape the anticipated problems of energy supply. However, there seems to be no clear explanation of the basis on which our foreseeable future energy problems could be eased. And in fact, a first attempt at a more exact definition of energy demand and its interaction with other objectives, such as economic ones, shows that it is a highly complex concept which we still hardly understand. The article explains in some detail why it is so difficult to understand energy demand

Demand elasticity of oil in Barbados

International Nuclear Information System (INIS)

Moore, Alvon

2011-01-01

The importation of oil is a significant component of Barbados' imports, rising from 7% of imports in 1998 to over 20% in 2009. This increase has impacted greatly on the level of foreign reserves. As a price-taker, relying entirely on imported oil for our energy needs could prove a continuous drain on the economy. With a view to formulating an appropriate energy policy for Barbados, this paper analyses the demand for oil using monthly data from 1998 to 2009. The paper estimates the elasticities of demand for oil by employing single equation cointegration approach and comparing the results with countries that rely heavily on imported oil and whose policy objective are to alter their energy structure to rely less on imported oil. The results show that the demand for oil imports is price inelastic in the long run. The consumption of oil is responsive to past consumption, prices, income, electricity consumption and the number of appliances imported in the short-run. A policy framework to reduce the use of oil for electricity consumption via alternative energy sources should be considered and the taxation of oil imports given its elasticity is a good source of revenue. - Highlights: → Demand for oil is price inelastic in the long-run (-0.552). → The relationship between oil demand and income is insignificant in the long run. → As electricity consumption increases by 1%, the demand for oil rises by 1.43%. → Need to determine if investments in alternative sources can offset demand for oil. → Investment in alternative resources may be required before gains are realised.

Demand forecasting of electricity in Indonesia with limited historical data

Science.gov (United States)

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).

Estimation of demand function on natural gas and study of demand analysis

Energy Technology Data Exchange (ETDEWEB)

Kim, Y.D. [Korea Energy Economics Institute, Euiwang (Korea, Republic of)

1998-04-01

Demand Function is estimated with several methods about the demand on natural gas, and analyzed per usage. Since the demand on natural gas, which has big share of heating use, has a close relationship with temperature, the inter-season trend of price and income elasticity is estimated considering temperature and economic formation. Per usage response of natural gas demand on the changes of price and income is also estimated. It was estimated that the response of gas demand on the changes of price and income occurs by the change of number of users in long term. In case of the response of unit consumption, only industrial use shows long-term response to price. Since gas price barely responds to the change of exchange rate, it seems to express the price-making mechanism that does not reflect timely the import condition such as exchange rate, etc. 16 refs., 12 figs., 13 tabs.

Elasticities of electricity demand in urban Indian households

International Nuclear Information System (INIS)

Filippini, Massimo; Pachauri, Shonali

2004-01-01

In the past, several electricity demand studies have been published for India based on aggregate macro data at the country or sub-national/state level. Since the underlying theory of consumer demand is based on the behaviour of individual agents, the use of micro data, which reflects individual and household behaviour, more closely, can shed greater light on the nature of consumer responses. In this paper, seasonal price and income elasticities of electricity demand in the residential sector of all urban areas of India are estimated for the first time using disaggregate level survey data for about 30,000 households. Three electricity demand functions have been econometrically estimated using monthly data for the winter, monsoon and summer season in order to understand the extent to which factors like income, prices, household size and other household specific characteristics, influence variations observed in individual households' electricity demand. The results show electricity demand is income and price inelastic in all three seasons, and that household, demographic and geographical variables are significant in determining electricity demand

DEMAND FOR TURKEY MEAT: PRICE EFFECT OR SPENDING EFFECT

Directory of Open Access Journals (Sweden)

Miguel Angel Martinez Damian

2016-08-01

Full Text Available Turkey meat is a white meat demand in Mexico, however, its consumption is still low. In order to explore the convenience of expanding the market and foresee if the industry should compete in price or expenditure, the aim of this work is to study the demand for turkey meat as part of a protein basket; that consists of beef, chicken, pork and egg. Methodologically an almost ideal demand model was used, in an economic sense, this model allows an optimal assignment representation through budget share equations as a function of prices and real expenditure within the bundle. With statistical information from secondary sources, the results showed that the demand for turkey meat responds inelastically to price, and that the response on spending is almost one. With the estimates of price and expenditure growth rates, in terms of an expansion policy in the turkey market, results conclude that spending is the most relevant factor in demand, followed to a lesser extent by price.

A demanding market

International Nuclear Information System (INIS)

Thomas, M.

1997-01-01

The article relates to the oil and natural gas market, and it gives a survey of proved reserves at the end of 1996 worldwide. The long term trend of increasing world energy demand has seen a major rise during 1996 when global consumption grew by 3%. But worldwide demand, excluding the Former Soviet Union, shows this figure increasing further to 3.7% for the whole of last year according to statistics. 3 figs

Crude oil prices: Robust demands strengthens outlook

International Nuclear Information System (INIS)

Simmons, M.R.

1996-01-01

This paper briefly summarizes the growth in the global demand for oil products by showing the historical trends in production and demand in developing countries. It shows world incremental production growth from 1985 to 1995 and developing countries's demands from 1971 to 1989. The paper goes on to make predictions as to whether the demand growth rate can be sustained. It provides information on the status of the world offshore drilling and production facilities to determine the capacity of this resource

The impact of job crafting on job demands, job resources, and well-being.

Science.gov (United States)

Tims, Maria; Bakker, Arnold B; Derks, Daantje

2013-04-01

This longitudinal study examined whether employees can impact their own well-being by crafting their job demands and resources. Based on the job demands-resources model, we hypothesized that employee job crafting would have an impact on work engagement, job satisfaction, and burnout through changes in job demands and job resources. Data was collected in a chemical plant at three time points with one month in between the measurement waves (N = 288). The results of structural equation modeling showed that employees who crafted their job resources in the first month of the study showed an increase in their structural and social resources over the course of the study (2 months). This increase in job resources was positively related to employee well-being (increased engagement and job satisfaction, and decreased burnout). Crafting job demands did not result in a change in job demands, but results revealed direct effects of crafting challenging demands on increases in well-being. We conclude that employee job crafting has a positive impact on well-being and that employees therefore should be offered opportunities to craft their own jobs.

Advertising media and cigarette demand.

Science.gov (United States)

Goel, Rajeev K

2011-01-01

Using state-level panel data for the USA spanning three decades, this research estimates the demand for cigarettes. The main contribution lies in studying the effects of cigarette advertising disaggregated across five qualitatively different groups. Results show cigarette demand to be near unit elastic, the income effects to be generally insignificant and border price effects and habit effects to be significant. Regarding advertising effects, aggregate cigarette advertising has a negative effect on smoking. Important differences across advertising media emerge when cigarette advertising is disaggregated. The effects of public entertainment and Internet cigarette advertising are stronger than those of other media. Anti-smoking messages accompanying print cigarette advertising seem relatively more effective. Implications for smoking control policy are discussed.

Electricity demand of manufacturing sector in Turkey. A translog cost approach

International Nuclear Information System (INIS)

Boeluek, Guelden; Koc, A. Ali

2010-01-01

This paper models factor demand for manufacturing sector in Turkey. We estimated a translog cost function with four factor consist of capital, labor, intermediate input and electricity over the 1980-2001. Our objective, taking in the consideration electricity as production input, was twofold: on the one hand, to estimate the price elasticity of electricity demand in manufacturing sector, and on the other hand to use cross-price and Morishima Elasticities of Substitution results for structural analysis regarding effects of electricity liberalization which initiated in 2001. Empirical result shows that electricity demand is relatively price sensitive (- 0.85). Our result in terms of electricity price is consistent with the previous studies. While electricity-labor and electricity-capital inputs are complementary, results indicate the existence of substitution possibilities between electricity and intermediate input. This means that changes in electricity prices have impact on labor demand and investment demand. These results have important implications for public policy. (author)

Electricity demand of manufacturing sector in Turkey. A translog cost approach

Energy Technology Data Exchange (ETDEWEB)

Boeluek, Guelden; Koc, A. Ali [Akdeniz University, Department of Economics, Antalya, 07058 (Turkey)

2010-05-15

This paper models factor demand for manufacturing sector in Turkey. We estimated a translog cost function with four factor consist of capital, labor, intermediate input and electricity over the 1980-2001. Our objective, taking in the consideration electricity as production input, was twofold: on the one hand, to estimate the price elasticity of electricity demand in manufacturing sector, and on the other hand to use cross-price and Morishima Elasticities of Substitution results for structural analysis regarding effects of electricity liberalization which initiated in 2001. Empirical result shows that electricity demand is relatively price sensitive (- 0.85). Our result in terms of electricity price is consistent with the previous studies. While electricity-labor and electricity-capital inputs are complementary, results indicate the existence of substitution possibilities between electricity and intermediate input. This means that changes in electricity prices have impact on labor demand and investment demand. These results have important implications for public policy. (author)

Climate change and peak demand for electricity: Evaluating policies for reducing peak demand under different climate change scenarios

Science.gov (United States)

Anthony, Abigail Walker

problems, pricing approaches are not well suited to ensure system reliability. This research shows that direct quantity controls are better suited for avoiding catastrophic failure that results when demand exceeds supply capacity.

Demand side management using profile steering

NARCIS (Netherlands)

Gerards, Marco Egbertus Theodorus; Toersche, Hermen; Hoogsteen, Gerwin; van der Klauw, Thijs; Hurink, Johann L.; Smit, Gerardus Johannes Maria

2015-01-01

Many Demand Side Management (DSM) approaches use energy prices as steering signals. This paper shows that such steering signals may result in power quality problems and high losses. As an alternative, this paper proposes to use desired (e.g., flat) power profiles as steering signals and presents an

Migration and Tourism Demand

Directory of Open Access Journals (Sweden)

Nuno Carlos LEITÃO

2012-02-01

Full Text Available This study considers the relationship between immigration and Portuguese tourism demand for the period 1995-2008, using a dynamic panel data approach. The findings indicate that Portuguese tourism increased significantly during the period in accordance with the values expected for a developed country. The regression results show that income, shock of immigration, population, and geographical distance between Portugal and countries of origin are the main determinants of Portuguese tourism.

Cognitive and collaborative demands of freight conductor activities: results and implications of a cognitive task analysis

Science.gov (United States)

2012-07-31

This report presents the results of a cognitive task analysis (CTA) that examined the cognitive and collaborative demands placed on conductors, as well as the knowledge and skills that experienced conductors have developed that enable them to operate...

ANALISIS PERMINTAAN (DEMAND ANALYSIS PELAYANAN KESEHATAN PUSKESMAS DI KABUPATEN MOJOKERTO

Directory of Open Access Journals (Sweden)

Wasis Budiarto

2012-09-01

Full Text Available A study on demand for health centre was carried out at Mojokerto Regency, East Java. The study convered 300 respondents (15 years old and over which were collected from two areas, urban (Kecamatan Bangsal and rural (Kecamatan Puri. The objectives of this study were to measure the demand for health centre services and to determine the influencing factors. A household survey was conducted in this study, using household and individual as unit of analysis and a multiple linier regression technique was used as analysis. In general, the result showed that needs were the most important factor affecting demand. In the urban health centres positive factor affecting individual demand were distance, family size and need, however in the rural health centre were cost, time and need were factors affecting demand. Factors affecting family demand for health services is different from individual demand. In urban and rural areas, family demand for health center was substitute alternative of the demand for the phycisian services.

Estimating elasticity for residential electricity demand in China.

Science.gov (United States)

Shi, G; Zheng, X; Song, F

2012-01-01

Residential demand for electricity is estimated for China using a unique household level dataset. Household electricity demand is specified as a function of local electricity price, household income, and a number of social-economic variables at household level. We find that the residential demand for electricity responds rather sensitively to its own price in China, which implies that there is significant potential to use the price instrument to conserve electricity consumption. Electricity elasticities across different heterogeneous household groups (e.g., rich versus poor and rural versus urban) are also estimated. The results show that the high income group is more price elastic than the low income group, while rural families are more price elastic than urban families. These results have important policy implications for designing an increasing block tariff.

Sensitivity analysis of energy demands on performance of CCHP system

International Nuclear Information System (INIS)

Li, C.Z.; Shi, Y.M.; Huang, X.H.

2008-01-01

Sensitivity analysis of energy demands is carried out in this paper to study their influence on performance of CCHP system. Energy demand is a very important and complex factor in the optimization model of CCHP system. Average, uncertainty and historical peaks are adopted to describe energy demands. The mix-integer nonlinear programming model (MINLP) which can reflect the three aspects of energy demands is established. Numerical studies are carried out based on energy demands of a hotel and a hospital. The influence of average, uncertainty and peaks of energy demands on optimal facility scheme and economic advantages of CCHP system are investigated. The optimization results show that the optimal GT's capacity and economy of CCHP system mainly lie on the average energy demands. Sum of capacities of GB and HE is equal to historical heating demand peaks, and sum of capacities of AR and ER are equal to historical cooling demand peaks. Maximum of PG is sensitive with historical peaks of energy demands and not influenced by uncertainty of energy demands, while the corresponding influence on DH is adverse

Modelling energy demand in the Norwegian building stock

Energy Technology Data Exchange (ETDEWEB)

Sartori, Igor

2008-07-15

Energy demand in the building stock in Norway represents about 40% of the final energy consumption, of which 22% goes to the residential sector and 18% to the service sector. In Norway there is a strong dependency on electricity for heating purposes, with electricity covering about 80% of the energy demand in buildings. The building sector can play an important role in the achievement of a more sustainable energy system. The work performed in the articles presented in this thesis investigates various aspects related to the energy demand in the building sector, both in singular cases and in the stock as a whole. The work performed in the first part of this thesis on development and survey of case studies provided background knowledge that was then used in the second part, on modelling the entire stock. In the first part, a literature survey of case studies showed that, in a life cycle perspective, the energy used in the operating phase of buildings is the single most important factor. Design of low-energy buildings is then beneficial and should be pursued, even though it implies a somewhat higher embodied energy. A case study was performed on a school building. First, a methodology using a Monte Carlo method in the calibration process was explored. Then, the calibrated model of the school was used to investigate measures for the achievement of high energy efficiency standard through renovation work. In the second part, a model was developed to study the energy demand in a scenario analysis. The results showed the robustness of policies that included conservation measures against the conflicting effects of the other policies. Adopting conservation measures on a large scale showed the potential to reduce both electricity and total energy demand from present day levels while the building stock keeps growing. The results also highlighted the inertia to change of the building stock, due to low activity levels compared to the stock size. It also became clear that a deeper

The Optimal Replenishment Policy under Trade Credit Financing with Ramp Type Demand and Demand Dependent Production Rate

Directory of Open Access Journals (Sweden)

Juanjuan Qin

2014-01-01

Full Text Available This paper investigates the optimal replenishment policy for the retailer with the ramp type demand and demand dependent production rate involving the trade credit financing, which is not reported in the literatures. First, the two inventory models are developed under the above situation. Second, the algorithms are given to optimize the replenishment cycle time and the order quantity for the retailer. Finally, the numerical examples are carried out to illustrate the optimal solutions and the sensitivity analysis is performed. The results show that if the value of production rate is small, the retailer will lower the frequency of putting the orders to cut down the order cost; if the production rate is high, the demand dependent production rate has no effect on the optimal decisions. When the trade credit is less than the growth stage time, the retailer will shorten the replenishment cycle; when it is larger than the breakpoint of the demand, within the maturity stage of the products, the trade credit has no effect on the optimal order cycle and the optimal order quantity.

Long-term uranium supply-demand analyses

International Nuclear Information System (INIS)

1986-12-01

It is the intention of this study to investigate the long-term uranium supply demand situation using a number of supply and demand related assumptions. For supply, these assumptions as used in the Resources and Production Projection (RAPP) model include country economic development status, and consequent lead times for exploration and development, uranium development status, country infrastructure, and uranium resources including the Reasonably Assured (RAR), Estimated Additional, Categories I and II, (EAR-I and II) and Speculative Resource categories. The demand assumptions were based on the ''pure'' reactor strategies developed by the NEA Working Party on Nuclear Fuel Cycle Requirements for the 1986 OECD (NEA)/IAEA reports ''Nuclear Energy and its Fuel Cycle: Prospects to 2025''. In addition for this study, a mixed strategy case was computed using the averages of the Plutonium (Pu) burning LWR high, and the improved LWR low cases. It is understandable that such a long-term analysis cannot present hard facts, but it can show which variables may in fact influence the long-term supply-demand situation. It is hoped that results of this study will provide valuable information for planners in the uranium supply and demand fields. Periodical re-analyses with updated data bases will be needed from time to time

Forecasting Ontario's blood supply and demand.

Science.gov (United States)

Drackley, Adam; Newbold, K Bruce; Paez, Antonio; Heddle, Nancy

2012-02-01

Given an aging population that requires increased medical care, an increasing number of deferrals from the donor pool, and a growing immigrant population that typically has lower donation rates, the purpose of this article is to forecast Ontario's blood supply and demand. We calculate age- and sex-specific donation and demand rates for blood supply based on 2008 data and project demand between 2008 and 2036 based on these rates and using population data from the Ontario Ministry of Finance. Results indicate that blood demand will outpace supply as early as 2012. For instance, while the total number of donations made by older cohorts is expected to increase in the coming years, the number of red blood cell (RBC) transfusions in the 70+ age group is forecasted grow from approximately 53% of all RBC transfusions in 2008 (209,515) in 2008 to 68% (546,996) by 2036. A series of alternate scenarios, including projections based on a 2% increase in supply per year and increased use of apheresis technology, delays supply shortfalls, but does not eliminate them without active management and/or multiple methods to increase supply and decrease demand. Predictions show that demand for blood products will outpace supply in the near future given current age- and sex-specific supply and demand rates. However, we note that the careful management of the blood supply by Canadian Blood Services, along with new medical techniques and the recruitment of new donors to the system, will remove future concerns. © 2012 American Association of Blood Banks.

Real-Time Demand Side Management Algorithm Using Stochastic Optimization

Directory of Open Access Journals (Sweden)

Moses Amoasi Acquah

2018-05-01

Full Text Available A demand side management technique is deployed along with battery energy-storage systems (BESS to lower the electricity cost by mitigating the peak load of a building. Most of the existing methods rely on manual operation of the BESS, or even an elaborate building energy-management system resorting to a deterministic method that is susceptible to unforeseen growth in demand. In this study, we propose a real-time optimal operating strategy for BESS based on density demand forecast and stochastic optimization. This method takes into consideration uncertainties in demand when accounting for an optimal BESS schedule, making it robust compared to the deterministic case. The proposed method is verified and tested against existing algorithms. Data obtained from a real site in South Korea is used for verification and testing. The results show that the proposed method is effective, even for the cases where the forecasted demand deviates from the observed demand.

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

NARCIS (Netherlands)

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

1999-01-01

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

Population ageing and healthcare demand: The case of Slovenia.

Science.gov (United States)

Vrhovec, Jure; Tajnikar, Maks

2016-11-01

The aim of this paper is to explore the consequences of demographic ageing on healthcare demand in Slovenia for primary care, secondary care, hospital day-care treatments, and hospitalisations. In the paper, we develop a model for making projections of the total number of treatments using the age-group projection method with the scenario approach. The model allows the number of treatments to be observed with respect to medical services, age groups and main disease groups. The results are presented for the cross-section years 2015, 2025 and 2035. The smallest increase in the number of treatments occurs in primary care, a larger one for secondary care, and the largest for hospital day-care services and hospitalisations (up to 29.9%). The structure of demand will also change. Demand for healthcare services for children and infants will decrease while demand for diseases associated with older age groups will increase, particularly for diseases of the circulatory system, eye and adnexa, and diseases of the blood and blood-forming organs. The results presented in this paper can help improve understanding of similar processes in other countries for total healthcare demand and for changes in the structure of demand. The results show that the healthcare system in Slovenia will face a major additional burden in the next 20 years. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Test Results for Caustic Demand Measurements on Tank 241-AX-101 and Tank 241-AX-103 Archive Samples

International Nuclear Information System (INIS)

Doll, Stephanie R.; Bolling, Stacie D.

2016-01-01

Caustic demand testing is used to determine the necessary amount of caustic required to neutralize species present in the Hanford tank waste and obtain a target molarity of free hydroxide for tank corrosion control. The presence and quantity of hydroxide-consuming analytes are just as important in determining the caustic demand as is the amount of free hydroxide present. No single data point can accurately predict whether a satisfactory hydroxide level is being met, as it is dependent on multiple factors (e.g., free hydroxide, buffers, amphoteric metal hydroxides, bicarbonate, etc.). This enclosure contains the caustic demand, scanning electron microscopy (SEM), polarized light microscopy (PLM), and X-ray diffraction (XRD) analysis for the tank 241-AX-101 (AX-101) and 241-AX-103 (AX-103) samples. The work was completed to fulfill a customer request outlined in the test plan, WRPS-1505529, ''Test Plan and Procedure for Caustic Demand Testing on Tank 241-AX-101 and Tank 241-AX-103 Archive Samples.'' The work results will provide a baseline to support planned retrieval of AX-101 and AX-103.

Test Results for Caustic Demand Measurements on Tank 241-AX-101 and Tank 241-AX-103 Archive Samples

Energy Technology Data Exchange (ETDEWEB)

Doll, Stephanie R. [Washington River Protection Solutions, Richland, WA (United States); Bolling, Stacie D. [Washington River Protection Solutions, Richland, WA (United States)

2016-07-14

Caustic demand testing is used to determine the necessary amount of caustic required to neutralize species present in the Hanford tank waste and obtain a target molarity of free hydroxide for tank corrosion control. The presence and quantity of hydroxide-consuming analytes are just as important in determining the caustic demand as is the amount of free hydroxide present. No single data point can accurately predict whether a satisfactory hydroxide level is being met, as it is dependent on multiple factors (e.g., free hydroxide, buffers, amphoteric metal hydroxides, bicarbonate, etc.). This enclosure contains the caustic demand, scanning electron microscopy (SEM), polarized light microscopy (PLM), and X-ray diffraction (XRD) analysis for the tank 241-AX-101 (AX-101) and 241-AX-103 (AX-103) samples. The work was completed to fulfill a customer request outlined in the test plan, WRPS-1505529, “Test Plan and Procedure for Caustic Demand Testing on Tank 241-AX-101 and Tank 241-AX-103 Archive Samples.” The work results will provide a baseline to support planned retrieval of AX-101 and AX-103.

Maximum power demand cost

International Nuclear Information System (INIS)

Biondi, L.

1998-01-01

The charging for a service is a supplier's remuneration for the expenses incurred in providing it. There are currently two charges for electricity: consumption and maximum demand. While no problem arises about the former, the issue is more complicated for the latter and the analysis in this article tends to show that the annual charge for maximum demand arbitrarily discriminates among consumer groups, to the disadvantage of some [it

A literature review of demand studies in world oil markets

International Nuclear Information System (INIS)

Atkins, F.; Tayyebi Jazayeri, S.M.

2004-04-01

The literature on world oil market demands was reviewed, summarized and organized into seven major groupings. The objective was to model economic behaviour before and after price shocks. In particular, the paper demonstrated how the price elasticity of demand in world oil markets is estimated. It also showed how the relationship between energy and oil consumption and income are estimated. The income elasticity of demand was also estimated, and empirical estimates of the elasticity of aggregate output regarding crude oil and energy prices were presented. The paper also referred to the transportation sector and estimates of the changing nature of seasonal factors. The review showed that there is much heterogeneity of econometric results. The literature showed that demand increased considerably in response to the price shocks of the 1970s, but these shocks were reversed in the 1980s when the increase in demand did not correspond with the decrease in price. Some of the literature is driven by the belief that there must be a stable, non-linear model that fits the data both before and after price shocks. The authors question whether this could be true and propose an alternative hypothesis that there is a different model that pertains to economic behaviour after price shocks. 15 refs., 7 tabs., 1 fig

Estimation of electricity demand of Iran using two heuristic algorithms

International Nuclear Information System (INIS)

Amjadi, M.H.; Nezamabadi-pour, H.; Farsangi, M.M.

2010-01-01

This paper deals with estimation of electricity demand of Iran based on economic indicators using Particle Swarm Optimization (PSO) Algorithm. The estimation is based on Gross Domestic Product (GDP), population, number of customers and average price electricity by developing two different estimation models: a linear model and a non-linear model. The proposed models are obtained based upon available actual data of 21 years; since 1980-2000. Then the models obtained are used to estimate the electricity demand of the target years; for a period of time e.g. 2001-2006 and the results obtained are compared with the actual demand during this period. Furthermore, to validate the results obtained by PSO, genetic algorithm (GA) is applied to solve the problem. The results show that the PSO is a useful optimization tool for solving the problem using two developed models and can be used as an alternative solution to estimate the future electricity demand.

Forecasting Hourly Water Demands With Seasonal Autoregressive Models for Real-Time Application

Science.gov (United States)

Chen, Jinduan; Boccelli, Dominic L.

2018-02-01

Consumer water demands are not typically measured at temporal or spatial scales adequate to support real-time decision making, and recent approaches for estimating unobserved demands using observed hydraulic measurements are generally not capable of forecasting demands and uncertainty information. While time series modeling has shown promise for representing total system demands, these models have generally not been evaluated at spatial scales appropriate for representative real-time modeling. This study investigates the use of a double-seasonal time series model to capture daily and weekly autocorrelations to both total system demands and regional aggregated demands at a scale that would capture demand variability across a distribution system. Emphasis was placed on the ability to forecast demands and quantify uncertainties with results compared to traditional time series pattern-based demand models as well as nonseasonal and single-seasonal time series models. Additional research included the implementation of an adaptive-parameter estimation scheme to update the time series model when unobserved changes occurred in the system. For two case studies, results showed that (1) for the smaller-scale aggregated water demands, the log-transformed time series model resulted in improved forecasts, (2) the double-seasonal model outperformed other models in terms of forecasting errors, and (3) the adaptive adjustment of parameters during forecasting improved the accuracy of the generated prediction intervals. These results illustrate the capabilities of time series modeling to forecast both water demands and uncertainty estimates at spatial scales commensurate for real-time modeling applications and provide a foundation for developing a real-time integrated demand-hydraulic model.

Oil prices: demand and supply. Lesson plan

OpenAIRE

anonymous

2005-01-01

Upon completion of this lesson, students will be able to list the determinants of demand and supply, recognize which factors will cause demand curves or supply curves to shift, determine equilibrium using a demand/supply graph, and show the effects on price and quantity when equilibrium changes.

Demand for abortion and post abortion care in Ibadan, Nigeria

Science.gov (United States)

2014-01-01

Background While induced abortion is considered to be illegal and socially unacceptable in Nigeria, it is still practiced by many women in the country. Poor family planning and unsafe abortion practices have daunting effects on maternal health. For instance, Nigeria is on the verge of not meeting the Millennium development goals on maternal health due to high maternal mortality ratio, estimated to be about 630 maternal deaths per 100,000 live births. Recent evidences have shown that a major factor in this trend is the high incidence of abortion in the country. The objective of this paper is, therefore, to investigate the factors determining the demand for abortion and post-abortion care in Ibadan city of Nigeria. Methods The study employed data from a hospital-based/exploratory survey carried out between March to September 2010. Closed ended questionnaires were administered to a sample of 384 women of reproductive age from three hospitals within the Ibadan metropolis in South West Nigeria. However, only 308 valid responses were received and analysed. A probit model was fitted to determine the socioeconomic factors that influence demand for abortion and post-abortion care. Results The results showed that 62% of respondents demanded for abortion while 52.3% of those that demanded for abortion received post-abortion care. The findings again showed that income was a significant determinant of abortion and post-abortion care demand. Women with higher income were more likely to demand abortion and post-abortion care. Married women were found to be less likely to demand for abortion and post-abortion care. Older women were significantly less likely to demand for abortion and post-abortion care. Mothers’ education was only statistically significant in determining abortion demand but not post-abortion care demand. Conclusion The findings suggest that while abortion is illegal in Nigeria, some women in the Ibadan city do abort unwanted pregnancies. The consequence of this

Dynamic inventory rationing strategies for inventory systems with two demand classes, Poisson demand and backordering

NARCIS (Netherlands)

Teunter, Ruud H.; Haneveld, Willem K. Klein

2008-01-01

We study inventory systems with two demand classes (critical and non-critical), Poisson demand and backordering. We analyze dynamic rationing strategies where the number of items reserved for critical demand depends on the remaining time until the next order arrives. Different from results in the

Sizewell: UK power demand

International Nuclear Information System (INIS)

Anon.

1986-01-01

The Sizewell Inquiry was about whether the next power stations to be built in the UK should be nuclear or coal and, if nuclear, PWRs or AGRs. During the period of the Inquiry forecasts of demand for electricity were low. Now, however, it seems that the forecast demand is much increased. This uncertainty in demand and the wide regional variations are examined in some detail. Facts and figures on electricity sales (area by area) are presented. Also the minutes of supply lost per consumer per year. These show that security of supply is also a problem. It is also shown that the way electricity is used has changed. Whilst electricity generation has been changing to large-scale, centralised power stations the demand patterns may make smaller scale, quickly-constructed units more sensible. The questions considered at the Sizewell Inquiry may, indeed, no longer be the right ones. (UK)

A semiparametric model of household gasoline demand

Energy Technology Data Exchange (ETDEWEB)

Wadud, Zia [Department of Civil Engineering, Bangladesh University of Engineering and Technology, Dhaka 1000 (Bangladesh); Noland, Robert B. [Alan M. Voorhees Transportation Center, Edward J. Bloustein School of Planning and Public Policy, Rutgers University, New Brunswick, NJ 08901 (United States); Graham, Daniel J. [Centre for Transport Studies, Dept of Civil and Environmental Engineering, Imperial College London, London, SW7 2AZ (United Kingdom)

2010-01-15

Gasoline demand studies typically generate a single price and income elasticity for a country. It is however possible that these elasticities may differ among various socio-economic groups. At the same time, parametric gasoline demand models may not be flexible enough to capture the changes in price elasticities with different levels of income. This paper models US gasoline demand using more flexible semiparametric techniques, accommodating the possibility of differences in responses among households. The econometric model employs a non-parametric bivariate smoothing for price and income and a parametric representation of other explanatory variables. Possible heterogeneity in price and income elasticities is modelled through interacting price and income with demographic variables. Results show that price responses do vary with demographic variables such as income, multiple vehicle holding, presence of multiple wage earners or rural or urban residential locations. Households' responses to a price change decrease with higher income. Multiple vehicle and multiple earner households also show higher sensitivity to a price change. Households located in urban areas reduce consumption more than those in rural areas in response to an increase in price. Comparison of the flexible semiparametric model with a parametric translog model, however, reveals no significant differences between results, and the parametric models have the advantage of lower computational requirements and better interpretability. (author)

Accounting for asymmetric price responses and underlying energy demand trends in OECD industrial energy demand

International Nuclear Information System (INIS)

Adeyemi, Olutomi I.; Hunt, Lester C.

2014-01-01

This paper explores the way technical progress and improvements in energy efficiency are captured when modelling OECD industrial energy demand. The industrial sectors of the developed world involve a number of different practices and processes utilising a range of different technologies. Consequently, given the derived demand nature of energy, it is vital when modelling industrial energy demand that the impact of technical progress is appropriately captured. However, the energy economics literature does not give a clear guide on how this can be achieved; one strand suggests that technical progress is ‘endogenous’ via asymmetric price responses whereas another strand suggests that it is ‘exogenous’. More recently, it has been suggested that potentially there is a role for both ‘endogenous’ technical progress and ‘exogenous’ technical progress and consequently the general model should be specified accordingly. This paper therefore attempts to model OECD industrial energy demand using annual time series data over the period 1962–2010 for 15 OECD countries. Using the Structural Time Series Model framework, the general specifications allow for both asymmetric price responses (for technical progress to impact endogenously) and an underlying energy demand trend (for technical progress and other factors to impact exogenously, but in a non-linear way). The results show that almost all of the preferred models for OECD industrial energy demand incorporate both a stochastic underlying energy demand trend and asymmetric price responses. This gives estimated long-run income elasticities in the range of 0.34 to 0.96; estimated long-run price-maximum elasticities in the range of − 0.06 to − 1.22; estimated long-run price-recovery elasticities in the range of 0.00 to − 0.27; and estimated long-run price-cut elasticities in the range of 0.00 to − 0.18. Furthermore, the analysis suggests that when modelling industrial energy demand there is a place for �

Effect of fare and travel time on the demand for domestic air transportation

Science.gov (United States)

Eriksen, S. E.; Liu, E. W.

1979-01-01

An econometric travel demand model was presented. The model was used for analyzing long haul domestic passenger markets in the United States. The results showed the sensitivities of demand to changes in fares and speed reflecting technology through more efficient aircraft designs.

Scenarios for Demand Growth of Metals in Electricity Generation Technologies, Cars, and Electronic Appliances.

Science.gov (United States)

Deetman, Sebastiaan; Pauliuk, Stefan; van Vuuren, Detlef P; van der Voet, Ester; Tukker, Arnold

2018-04-17

This study provides scenarios toward 2050 for the demand of five metals in electricity production, cars, and electronic appliances. The metals considered are copper, tantalum, neodymium, cobalt, and lithium. The study shows how highly technology-specific data on products and material flows can be used in integrated assessment models to assess global resource and metal demand. We use the Shared Socio-economic Pathways as implemented by the IMAGE integrated assessment model as a starting point. This allows us to translate information on the use of electronic appliances, cars, and renewable energy technologies into quantitative data on metal flows, through application of metal content estimates in combination with a dynamic stock model. Results show that total demand for copper, neodymium, and tantalum might increase by a factor of roughly 2 to 3.2, mostly as a result of population and GDP growth. The demand for lithium and cobalt is expected to increase much more, by a factor 10 to more than 20, as a result of future (hybrid) electric car purchases. This means that not just demographics, but also climate policies can strongly increase metal demand. This shows the importance of studying the issues of climate change and resource depletion together, in one modeling framework.

Scenarios for Demand Growth of Metals in Electricity Generation Technologies, Cars, and Electronic Appliances

Science.gov (United States)

2018-01-01

This study provides scenarios toward 2050 for the demand of five metals in electricity production, cars, and electronic appliances. The metals considered are copper, tantalum, neodymium, cobalt, and lithium. The study shows how highly technology-specific data on products and material flows can be used in integrated assessment models to assess global resource and metal demand. We use the Shared Socio-economic Pathways as implemented by the IMAGE integrated assessment model as a starting point. This allows us to translate information on the use of electronic appliances, cars, and renewable energy technologies into quantitative data on metal flows, through application of metal content estimates in combination with a dynamic stock model. Results show that total demand for copper, neodymium, and tantalum might increase by a factor of roughly 2 to 3.2, mostly as a result of population and GDP growth. The demand for lithium and cobalt is expected to increase much more, by a factor 10 to more than 20, as a result of future (hybrid) electric car purchases. This means that not just demographics, but also climate policies can strongly increase metal demand. This shows the importance of studying the issues of climate change and resource depletion together, in one modeling framework. PMID:29533657

Impacts of Demand-Side Resources on Electric Transmission Planning

Energy Technology Data Exchange (ETDEWEB)

Hadley, Stanton W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Sanstad, Alan H. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

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 were 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.

Stochastic–multiobjective market equilibrium analysis of a demand response program in energy market under uncertainty

International Nuclear Information System (INIS)

Hu, Ming-Che; Lu, Su-Ying; Chen, Yen-Haw

2016-01-01

Highlights: • Analyze the impact of a demand response program under uncertainty. • Stochastic Nash–Cournot competition model is formulated. • Case study of the Taiwanese electric power market is conducted. • Demand response decreases power price, generation, and emissions. • Demand uncertainty increases energy price and supply risk in the results. - Abstract: In the electricity market, demand response programs are designed to shift peak demand and enhance system reliability. A demand response program can reduce peak energy demand, power transmission congestion, or high energy-price conditions by changing consumption patterns. The purpose of this research is to analyze the impact of a demand response program in the energy market, under demand uncertainty. A stochastic–multiobjective Nash–Cournot competition model is formulated to simulate demand response in an uncertain energy market. Then, Karush–Kuhn–Tucker optimality conditions and a linear complementarity problem are derived for the stochastic Nash–Cournot model. Accordingly, the linear complementarity problem is solved and its stochastic market equilibrium solution is determined by using a general algebraic modeling system. Additionally, the case of the Taiwanese electric power market is taken up here, and the results show that a demand response program is capable of reducing peak energy consumption, energy price, and carbon dioxide emissions. The results show that demand response program decreases electricity price by 2–10%, total electricity generation by 0.5–2%, and carbon dioxide emissions by 0.5–2.5% in the Taiwanese power market. In the simulation, demand uncertainty leads to an 2–7% increase in energy price and supply risk in the market. Additionally, tradeoffs between cost and carbon dioxide emissions are presented.

Modeling and forecasting natural gas demand in Bangladesh

International Nuclear Information System (INIS)

Wadud, Zia; Dey, Himadri S.; Kabir, Md. Ashfanoor; Khan, Shahidul I.

2011-01-01

Natural gas is the major indigenous source of energy in Bangladesh and accounts for almost one-half of all primary energy used in the country. Per capita and total energy use in Bangladesh is still very small, and it is important to understand how energy, and natural gas demand will evolve in the future. We develop a dynamic econometric model to understand the natural gas demand in Bangladesh, both in the national level, and also for a few sub-sectors. Our demand model shows large long run income elasticity - around 1.5 - for aggregate demand for natural gas. Forecasts into the future also show a larger demand in the future than predicted by various national and multilateral organizations. Even then, it is possible that our forecasts could still be at the lower end of the future energy demand. Price response was statistically not different from zero, indicating that prices are possibly too low and that there is a large suppressed demand for natural gas in the country. - Highlights: → Natural gas demand is modeled using dynamic econometric methods, first of its kind in Bangladesh. → Income elasticity for aggregate natural gas demand in Bangladesh is large-around 1.5. → Demand is price insensitive, indicating too low prices and/or presence of large suppressed demand. → Demand forecasts reveal large divergence from previous estimates, which is important for planning. → Attempts to model demand for end-use sectors were successful only for the industrial sector.

Modeling and forecasting natural gas demand in Bangladesh

Energy Technology Data Exchange (ETDEWEB)

Wadud, Zia, E-mail: ziawadud@yahoo.com [Bangladesh University of Engineering and Technology (Bangladesh); Dey, Himadri S. [University of Notre Dame (United States); Kabir, Md. Ashfanoor; Khan, Shahidul I. [Bangladesh University of Engineering and Technology (Bangladesh)

2011-11-15

Natural gas is the major indigenous source of energy in Bangladesh and accounts for almost one-half of all primary energy used in the country. Per capita and total energy use in Bangladesh is still very small, and it is important to understand how energy, and natural gas demand will evolve in the future. We develop a dynamic econometric model to understand the natural gas demand in Bangladesh, both in the national level, and also for a few sub-sectors. Our demand model shows large long run income elasticity - around 1.5 - for aggregate demand for natural gas. Forecasts into the future also show a larger demand in the future than predicted by various national and multilateral organizations. Even then, it is possible that our forecasts could still be at the lower end of the future energy demand. Price response was statistically not different from zero, indicating that prices are possibly too low and that there is a large suppressed demand for natural gas in the country. - Highlights: > Natural gas demand is modeled using dynamic econometric methods, first of its kind in Bangladesh. > Income elasticity for aggregate natural gas demand in Bangladesh is large-around 1.5. > Demand is price insensitive, indicating too low prices and/or presence of large suppressed demand. > Demand forecasts reveal large divergence from previous estimates, which is important for planning. > Attempts to model demand for end-use sectors were successful only for the industrial sector.

Gas demand forecasting by a new artificial intelligent algorithm

Science.gov (United States)

Khatibi. B, Vahid; Khatibi, Elham

2012-01-01

Energy demand forecasting is a key issue for consumers and generators in all energy markets in the world. This paper presents a new forecasting algorithm for daily gas demand prediction. This algorithm combines a wavelet transform and forecasting models such as multi-layer perceptron (MLP), linear regression or GARCH. The proposed method is applied to real data from the UK gas markets to evaluate their performance. The results show that the forecasting accuracy is improved significantly by using the proposed method.

Price elasticity of demand: An overlooked concept

International Nuclear Information System (INIS)

Anon.

1995-01-01

An all-too-common mistake in analyzing the uranium market is to assume that demand for uranium is driven only by the design and operational parameters of nuclear power plants. Because it is generally accepted that demand for uranium is inelastic, not much attention has been given to how prices can indirectly affect demand. The purpose of this paper is to highlight the factors that are most sensitive to uranium prices, and to show how they alter uranium demand

Consumer Demand for Healthy Diet: New Evidence from the Healthy Eating Index

OpenAIRE

Gao, Zhifeng; Yu, Xiaohua; Lee, Jonq-Ying

2011-01-01

A large volume of literature has been focusing on the measure of diet quality and consumer demand for food. However, little has estimated consumer demand for diet quality. In this article, we systematically estimate consumer demand for diet quality using the healthy eating index (HEI) developed by the U.S. Department of Agriculture. The Results show that consumers have insufficient consumption of the food containing dark green, orange vegetable, legumes and total grain. Age and education have...

Household consumption, associated fossil fuel demand and carbon dioxide emissions: The case of Greece between 1990 and 2006

International Nuclear Information System (INIS)

Papathanasopoulou, Eleni

2010-01-01

This paper explores how Greece's household consumption has changed between 1990 and 2006 and its environmental implications in terms of fossil fuel demand and carbon dioxide (CO 2 ) emissions. The results show that the 44% increase in Greece's household expenditure between 1990 and 2006 was accompanied by a 67% increase in fossil fuel demand. Of this total, indirect demand accounted for approximately 60% throughout the 16-year period, increasing by 56% overall, whereas direct fossil fuel demand grew by 80%. The results also show that associated CO 2 emissions increased by 60%, resulting in a 'relative decoupling' from energy demand. This relative decoupling is shown to be due to fossil fuel mix changes from the supply side rather than action from consumers. These insights highlight the opportunities for demand-side policies to further reduce fossil fuel demand and CO 2 emissions, allowing Greece to set more proactive and ambitious post-Kyoto targets.

Modelling electricity demand in Ghana revisited: The role of policy regime changes

International Nuclear Information System (INIS)

Adom, Philip Kofi; Bekoe, William

2013-01-01

As policy regime changes, demand elasticities are unlikely to be constant since individuals change how they form their expectations, and this will change the estimated decision rules. In this paper, the time-varying nature of electricity demand elasticities prior to and post the economic reform period in Ghana is analysed using the FM-OLS. Three different sample periods -pre-reform, post-reform, and full-period- was used in the analysis. The result from the full-sample period revealed that in the long-run electricity demand is significantly affected by industry efficiency, industry value added, and real per capita GDP. Urbanization rate, however, has no significant effect. The pre-reform estimate showed lower income, output, and urbanization elasticities but higher industry energy efficiency elasticity relative to the post-reform period. This suggests that technological change in the pre-reform period has been energy saving whilst technological change in the post reform period has been energy consuming. The result further showed evidence of changing structure of the economy from the more energy intensive sector to the less energy intensive sector after the reform. Government should renew her effort in promoting energy saving technologies in the industrial sector and adjust the industrial structure to encourage the expansion of low energy intensive industries or high technology efficient industries. - Highlights: • The study investigates time-varying nature of demand elasticities prior to 1983 and after 1983. • Result shows differences in demand elasticities prior to and post the reform. • Pre-reform period is characterised with energy saving technology. • Post-reform period is characterised with energy consuming technology. • The post-reform result reveals evidence of gradual structural shift in the economy

The impact of task demand on visual word recognition.

Science.gov (United States)

Yang, J; Zevin, J

2014-07-11

The left occipitotemporal cortex has been found sensitive to the hierarchy of increasingly complex features in visually presented words, from individual letters to bigrams and morphemes. However, whether this sensitivity is a stable property of the brain regions engaged by word recognition is still unclear. To address the issue, the current study investigated whether different task demands modify this sensitivity. Participants viewed real English words and stimuli with hierarchical word-likeness while performing a lexical decision task (i.e., to decide whether each presented stimulus is a real word) and a symbol detection task. General linear model and independent component analysis indicated strong activation in the fronto-parietal and temporal regions during the two tasks. Furthermore, the bilateral inferior frontal gyrus and insula showed significant interaction effects between task demand and stimulus type in the pseudoword condition. The occipitotemporal cortex showed strong main effects for task demand and stimulus type, but no sensitivity to the hierarchical word-likeness was found. These results suggest that different task demands on semantic, phonological and orthographic processes can influence the involvement of the relevant regions during visual word recognition. Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.

Electricity demand profile with high penetration of heat pumps in Nordic area

DEFF Research Database (Denmark)

Liu, Zhaoxi; Wu, Qiuwei; Nielsen, Arne Hejde

2013-01-01

This paper presents the heat pump (HP) demand profile with high HP penetration in the Nordic area in order to achieve the carbon neutrality power system. The calculation method in the European Standard EN14825 was used to estimate the HP electricity demand profile. The study results show...... there will be high power demand from HPs and the selection of supplemental heating for heat pumps has a big impact on the peak electrical power load of heating. The study in this paper gives an estimate of the scale of the electricity demand with high penetration of heat pumps in the Nordic area....

2015 California Demand Response Potential Study - Charting California’s Demand Response Future. Interim Report on Phase 1 Results

Energy Technology Data Exchange (ETDEWEB)

Alstone, Peter; Potter, Jennifer; Piette, Mary Ann; Schwartz, Peter; Berger, Michael A.; Dunn, Laurel N.; Smith, Sarah J.; Sohn, Michael D.; Aghajanzadeh, Arian; Stensson, Sofia; Szinai, Julia

2016-04-01

Demand response (DR) is an important resource for keeping the electricity grid stable and efficient; deferring upgrades to generation, transmission, and distribution systems; and providing other customer economic benefits. This study estimates the potential size and cost of the available DR resource for California’s three investor-owned utilities (IOUs), as the California Public Utilities Commission (CPUC) evaluates how to enhance the role of DR in meeting California’s resource planning needs and operational requirements. As the state forges a clean energy future, the contributions of wind and solar electricity from centralized and distributed generation will fundamentally change the power grid’s operational dynamics. This transition requires careful planning to ensure sufficient capacity is available with the right characteristics – flexibility and fast response – to meet reliability needs. Illustrated is a snapshot of how net load (the difference between demand and intermittent renewables) is expected to shift. Increasing contributions from renewable generation introduces steeper ramps and a shift, into the evening, of the hours that drive capacity needs. These hours of peak capacity need are indicated by the black dots on the plots. Ultimately this study quantifies the ability and the cost of using DR resources to help meet the capacity need at these forecasted critical hours in the state.

Investigating Impacts of Climate Change on Irrigation Water Demands and Its Resulting Consequences on Groundwater Using CMIP5 Models.

Science.gov (United States)

Goodarzi, Mustafa; Abedi-Koupai, Jahangir; Heidarpour, Manouchehr

2018-04-15

In this study, the impacts of climate change on crop water requirements and irrigation water requirements on the regional cropping pattern were evaluated using two climate change scenarios and combinations of 20 GCM models. Different models including CROPWAT, MODFLOW, and statistical models were used to evaluate the climate change impacts. The results showed that in the future period (2017 to 2046) the temperature in all months of the year will increase at all stations. The average annual precipitation decline in Isfahan, Tiran, Flavarjan, and Lenj stations for RCP 4.5 and RCP 8.5 scenarios are 18.6 and 27.6%, 15.2 and 18%, 22.5 and 31.5%, and 10.5 and 12.1%, respectively. The average increase in the evapotranspiration for RCP 4.5 and RCP 8.5 scenarios are about 2.5 and 4.1%, respectively. The irrigation water demands increases considerably and for some crops, on average 18%. Among the existing crops in the cropping pattern, barley, cumin, onion, wheat, and forage crops are more sensitive and their water demand will increase significantly. Results indicate that climate change could have a significant impact on water resources consumption. By considering irrigation efficiency in the region, climate change impacts will result in about 35 to 50 million m 3 /year, over-extraction from the aquifer. This additional exploitation causes an extra drop of 0.4 to 0.8 m in groundwater table per year in the aquifer. Therefore, with regard to the critical condition of the aquifer, management and preventive measures to deal with climate change in the future is absolutely necessary. © 2018, National Ground Water Association.

Demand response in energy markets

International Nuclear Information System (INIS)

Skytte, K.; Birk Mortensen, J.

2004-11-01

Improving the ability of energy demand to respond to wholesale prices during critical periods of the spot market can reduce the total costs of reliably meeting demand, and the level and volatility of the prices. This fact has lead to a growing interest in the short-run demand response. There has especially been a growing interest in the electricity market where peak-load periods with high spot prices and occasional local blackouts have recently been seen. Market concentration at the supply side can result in even higher peak-load prices. Demand response by shifting demand from peak to base-load periods can counteract the market power in the peak-load. However, demand response has so far been modest since the current short-term price elasticity seems to be small. This is also the case for related markets, for example, green certificates where the demand is determined as a percentage of the power demand, or for heat and natural gas markets. This raises a number of interesting research issues: 1) Demand response in different energy markets, 2) Estimation of price elasticity and flexibility, 3) Stimulation of demand response, 4) Regulation, policy and modelling aspects, 5) Demand response and market power at the supply side, 6) Energy security of supply, 7) Demand response in forward, spot, ancillary service, balance and capacity markets, 8) Demand response in deviated markets, e.g., emission, futures, and green certificate markets, 9) Value of increased demand response, 10) Flexible households. (BA)

Regional demand and supply projections for outdoor recreation

Science.gov (United States)

Donald B. K. English; Carter J. Betz; J. Mark Young; John C. Bergstrom; H. Ken Cordell

1993-01-01

This paper develops regional recreation supply and demand projections, by combining coefficients from the national 1989 RPA Assessment models with regional regressor values. Regional recreation opportunity estimates also are developed, based on regional travel behavior. Results show important regional variations in projections of recreation opportunities, trip supply,...

Modelling demand for crude oil products in Spain

International Nuclear Information System (INIS)

Pedregal, D.J.; Dejuan, O.; Gomez, N.; Tobarra, M.A.

2009-01-01

This paper develops an econometric model for the five most important crude oil products demand in Spain. The aim is the estimation of a range of elasticities of such demands that would serve as the basis for an applied general equilibrium model used for forecasting energy demand in a broader framework. The main distinctive features of the system with respect to previous literature are (1) it takes advantage of monthly information coming from very different information sources and (2) multivariate unobserved components (UC) models are implemented allowing for a separate analysis of long- and short-run relations. UC models decompose time series into a number of unobserved though economic meaningful components mainly trend, seasonal and irregular. A module is added to such structure to take into account the influence of exogenous variables necessary to compute price, cross and income elasticities. Since all models implemented are multivariate in nature, the demand components are allowed to interact among them through the system noises (similar to a seemingly unrelated equations model). The results show unambiguously that the main factor driving demand is real income with prices having little impact on energy consumption. (author)

Modelling demand for crude oil products in Spain

Energy Technology Data Exchange (ETDEWEB)

Pedregal, D.J. [Escuela Tecnica Superior de Ingenieros Industriales and Instituto de Matematica Aplicada a la Ciencia y la Ingenieria (IMACI), Universidad de Castilla-La Mancha (UCLM), Avenida Camilo Jose Cela s/n, 13071 Ciudad Real (Spain); Dejuan, O.; Gomez, N.; Tobarra, M.A. [Facultad de Ciencias Economicas y Empresariales, Universidad de Castilla-La Mancha (UCLM) (Spain)

2009-11-15

This paper develops an econometric model for the five most important crude oil products demand in Spain. The aim is the estimation of a range of elasticities of such demands that would serve as the basis for an applied general equilibrium model used for forecasting energy demand in a broader framework. The main distinctive features of the system with respect to previous literature are (1) it takes advantage of monthly information coming from very different information sources and (2) multivariate unobserved components (UC) models are implemented allowing for a separate analysis of long- and short-run relations. UC models decompose time series into a number of unobserved though economic meaningful components mainly trend, seasonal and irregular. A module is added to such structure to take into account the influence of exogenous variables necessary to compute price, cross and income elasticities. Since all models implemented are multivariate in nature, the demand components are allowed to interact among them through the system noises (similar to a seemingly unrelated equations model). The results show unambiguously that the main factor driving demand is real income with prices having little impact on energy consumption. (author)

Effect of Physician Gender on Demand for Pap Tests

OpenAIRE

Lin, Tsui-Fang; Chen, Jennjou

2014-01-01

People’s demand for preventive medical care is one type of investment in health. The aim of this paper is to examine women’s demand for secondary prevention in Taiwan, focusing on the role a physician’s gender plays in women’s inclination to undergo Pap tests. Our estimation results show that regional ratio of female doctors has a positive and significant effect on utilization of Pap tests for the full sample and for women aged below 30. In addition, doctor’s gender matters only in utilizatio...

The Relationship between Farm-Gate and Consumer Demand for Meat Products in Iran

Directory of Open Access Journals (Sweden)

fatemeh fathi

2014-03-01

Full Text Available Demand for farm output is theoretically consistent with consumer demand and marketing performance. Many studies have focused on demand interrelationships at the retail level, but not on the demand for farm output. In this study, derived demand elasticities of sheep, beef and chicken were estimated in a complete system of demand functions by seemingly unrelated regression estimator (SURE for the years 1984-2012. Sheep, beef and chicken are considered as inputs for food processing and marketing and so their corresponding derived demands are related to consumer demand and marketing performance. Based on findings of this study, the elasticities of substitution are estimated to be 0.26 for sheep, 0.38 for cattle and 0.32 for poultry. The results showed that derived demand elasticity is more sensitive than the one measured by the traditional method. The price elasticities of the derived demands for the three types of meat were calculated-0.922, -0.775 and -0.716 for sheep, beef and chicken, respectively. This presents that demands at the farm level are less elastic than the associated demands at the retail level. Therefore, policies that change meat price at farm or retail level affect marginal markets of other meat products. According to the results of this study, it is necessary for policy makers to have information on the derived demand elasticity.

A Hybrid Approach on Tourism Demand Forecasting

Science.gov (United States)

Nor, M. E.; Nurul, A. I. M.; Rusiman, M. S.

2018-04-01

Tourism has become one of the important industries that contributes to the country’s economy. Tourism demand forecasting gives valuable information to policy makers, decision makers and organizations related to tourism industry in order to make crucial decision and planning. However, it is challenging to produce an accurate forecast since economic data such as the tourism data is affected by social, economic and environmental factors. In this study, an equally-weighted hybrid method, which is a combination of Box-Jenkins and Artificial Neural Networks, was applied to forecast Malaysia’s tourism demand. The forecasting performance was assessed by taking the each individual method as a benchmark. The results showed that this hybrid approach outperformed the other two models

Better Water Demand and Pipe Description Improve the Distribution Network Modeling Results

Science.gov (United States)

Distribution system modeling simplifies pipe network in skeletonization and simulates the flow and water quality by using generalized water demand patterns. While widely used, the approach has not been examined fully on how it impacts the modeling fidelity. This study intends to ...

Demand for abortion and post abortion care in Ibadan, Nigeria.

Science.gov (United States)

Awoyemi, Bosede O; Novignon, Jacob

2014-01-01

While induced abortion is considered to be illegal and socially unacceptable in Nigeria, it is still practiced by many women in the country. Poor family planning and unsafe abortion practices have daunting effects on maternal health. For instance, Nigeria is on the verge of not meeting the Millennium development goals on maternal health due to high maternal mortality ratio, estimated to be about 630 maternal deaths per 100,000 live births. Recent evidences have shown that a major factor in this trend is the high incidence of abortion in the country. The objective of this paper is, therefore, to investigate the factors determining the demand for abortion and post-abortion care in Ibadan city of Nigeria. The study employed data from a hospital-based/exploratory survey carried out between March to September 2010. Closed ended questionnaires were administered to a sample of 384 women of reproductive age from three hospitals within the Ibadan metropolis in South West Nigeria. However, only 308 valid responses were received and analysed. A probit model was fitted to determine the socioeconomic factors that influence demand for abortion and post-abortion care. The results showed that 62% of respondents demanded for abortion while 52.3% of those that demanded for abortion received post-abortion care. The findings again showed that income was a significant determinant of abortion and post-abortion care demand. Women with higher income were more likely to demand abortion and post-abortion care. Married women were found to be less likely to demand for abortion and post-abortion care. Older women were significantly less likely to demand for abortion and post-abortion care. Mothers' education was only statistically significant in determining abortion demand but not post-abortion care demand. The findings suggest that while abortion is illegal in Nigeria, some women in the Ibadan city do abort unwanted pregnancies. The consequence of this in the absence of proper post

Power systems balancing with high penetration renewables: The potential of demand response in Hawaii

International Nuclear Information System (INIS)

Critz, D. Karl; Busche, Sarah; Connors, Stephen

2013-01-01

Highlights: • Demand response for Oahu results in system cost savings. • Demand response improves thermal power plant operations. • Increased use of wind generation possible with demand response. • WILMAR model used to simulate various levels and prices of demand response. - Abstract: The State of Hawaii’s Clean Energy policies call for 40% of the state’s electricity to be supplied by renewable sources by 2030. A recent study focusing on the island of Oahu showed that meeting large amounts of the island’s electricity needs with wind and solar introduced significant operational challenges, especially when renewable generation varies from forecasts. This paper focuses on the potential of demand response in balancing supply and demand on an hourly basis. Using the WILMAR model, various levels and prices of demand response were simulated. Results indicate that demand response has the potential to smooth overall power system operation, with production cost savings arising from both improved thermal power plant operations and increased wind production. Demand response program design and cost structure is then discussed drawing from industry experience in direct load control programs

Exhaustion and Emotional Demands in China:A Large-Scale Investigation across Occupations

Institute of Scientific and Technical Information of China (English)

Kelly Z.Peng

2017-01-01

As the Chinese economy moves toward a market-based model,employees are likely to face more emotional demands and exhaustion at work.However,there are some unique aspects to the emotional demands of work in the Chinese cultural context.We investigate emotional demands and exhaustion in China with a large-scale sample across the six major occupations identified by the Holland classification system.Results show that incumbents of social and enterprising jobs face higher emotional demands.Unexpectedly,exhaustion differs significantly between conventional and other types of jobs.Building on the Job Demand-Resources (JD-R) model,job crafting and the cultural context,we propose that the nonlinear relationship of emotional demands and exhaustion exists only when emotional intelligence is low.Our study may inform practitioners and policy makers in Chinese enterprises about emotional demands and exhaustion for various occupations and the importance of selection and training programs in emotional intelligence.

Teaching Aggregate Demand and Supply Models

Science.gov (United States)

Wells, Graeme

2010-01-01

The author analyzes the inflation-targeting model that underlies recent textbook expositions of the aggregate demand-aggregate supply approach used in introductory courses in macroeconomics. He shows how numerical simulations of a model with inflation inertia can be used as a tool to help students understand adjustments in response to demand and…

Pattern of demand for children in Pakistan.

Science.gov (United States)

Ahmed, T

1992-01-01

The study aim was to determine the pattern of demand for children and to suggest ways to introduce the idea of a small-family norm and reduce the unmet need for contraception in Pakistan. The concept of demand for children included the wantedness of the last birth and the timing of the next birth and changed with stage in reproductive life cycle. Data were obtained from the Pakistan Contraception Prevalence Survey of 1984/85. Pakistan's strong patriarchal system emphasized rapid achievement of first pregnancy in order to assure the perpetuation of the lineage. Female status, even with advanced education, emphasized fecundity and producing a male heir. The birthing pattern among rural and urban lower-class women is to bear 3-4 children early in marriage. Evidence from prior surveys showed that educated women plan for a delay in second birth. Of the 6655 ever pregnant and nonsterilized women, about 48% of currently married women desired discontinuation of childbearing. 18% desired a delay of childbearing by 2 years and 10% desired no more children after a last undesired pregnancy. Unmet need was estimated at 17% of all women in the sample. Women desiring no more children were primarily older with 6-8 prior births. Indirect fertility estimates were generated by using Arriaga's techniques for stages of family formation. The resulting estimates showed that higher-parity women desiring no more children still had 2 more children, which was evidence of unmet need. Those desiring more children had higher fertility than those not desiring more children. These women also showed different patterns in their total demand for children, ideal family size, currently living children, and desire for their next birth. Ideal size tended to rise over the length of a marriage, which may mean that women with growing families may justify unwanted fertility. Duration of marriage was viewed as a reasonable indicator of need for fertility control and the concomitant need for outreach

Demand Uncertainty

DEFF Research Database (Denmark)

Nguyen, Daniel Xuyen

This paper presents a model of trade that explains why firms wait to export and why many exporters fail. Firms face uncertain demands that are only realized after the firm enters the destination. The model retools the timing of uncertainty resolution found in productivity heterogeneity models....... This retooling addresses several shortcomings. First, the imperfect correlation of demands reconciles the sales variation observed in and across destinations. Second, since demands for the firm's output are correlated across destinations, a firm can use previously realized demands to forecast unknown demands...... in untested destinations. The option to forecast demands causes firms to delay exporting in order to gather more information about foreign demand. Third, since uncertainty is resolved after entry, many firms enter a destination and then exit after learning that they cannot profit. This prediction reconciles...

Energy Systems Scenario Modelling and Long Term Forecasting of Hourly Electricity Demand

DEFF Research Database (Denmark)

Alberg Østergaard, Poul; Møller Andersen, Frits; Kwon, Pil Seok

2015-01-01

. The results show that even with a limited short term electric car fleet, these will have a significant effect on the energy system; the energy system’s ability to integrate wind power and the demand for condensing power generation capacity in the system. Charging patterns and flexibility have significant...... or inflexible electric vehicles and individual heat pumps, and in the long term it is investigated what the effects of changes in the load profiles due to changing weights of demand sectors are. The analyses are based on energy systems simulations using EnergyPLAN and demand forecasting using the Helena model...... effects on this. Likewise, individual heat pumps may affect the system operation if they are equipped with heat storages. The analyses also show that the long term changes in electricity demand curve profiles have little impact on the energy system performance. The flexibility given by heat pumps...

Service Demand Discovery Mechanism for Mobile Social Networks.

Science.gov (United States)

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.

Demand response in Indian electricity market

International Nuclear Information System (INIS)

Siddiqui, Md Zakaria; Maere d'Aertrycke, Gauthier de; Smeers, Yves

2012-01-01

This paper outlines a methodology for implementing cost of service regulation in retail market for electricity in India when wholesale market is liberalised and operates through an hourly spot market. As in a developing country context political considerations make tariff levels more important than supply security, satisfying the earmarked level of demand takes a back seat. Retail market regulators are often forced by politicians to keep the retail tariff at suboptimal level. This imposes budget constraint on distribution companies to procure electricity that it requires to meet the earmarked level of demand. This is the way demand response is introduced in the system and has its impact on spot market prices. We model such a situation of not being able to serve the earmarked demand as disutility to the regulator which has to be minimised and we compute associated equilibrium. This results in systematic mechanism for cutting loads. We find that even a small cut in ability of the distribution companies to procure electricity from the spot market has profound impact on the prices in the spot market. - Highlights: ► Modelling the impact of retail tariff in different states on spot prices of electricity in India. ► Retail tariffs are usually fixed below appropriate levels by states due to political reasons. ► Due to revenue constraint distribution utility withdraws demand from spot market in peak hours. ► This adversely affects the scarcity rent of generators and subsequently future investment. ► We show possibility of strategic behaviour among state level regulators in setting retail tariff.

Mining residential water and electricity demand data in Southern California to inform demand management strategies

Science.gov (United States)

Cominola, A.; Spang, E. S.; Giuliani, M.; Castelletti, A.; Loge, F. J.; Lund, J. R.

2016-12-01

characterizing them with respect to consumption profiles features and socio- demographic information. Results show how such better understanding of the considered users' community allows spotting potentially interesting areas for water and energy demand management interventions.

Energy demand projection of China using a path-coefficient analysis and PSO–GA approach

International Nuclear Information System (INIS)

Yu Shiwei; Zhu Kejun; Zhang Xian

2012-01-01

Highlights: ► The effect mechanism of China’s energy demand is investigated detailedly. ► A hybrid algorithm PSO–GA optimal energy demands estimating model for China. ► China’s energy demand will reach 4.48 billion tce in 2015. ► The proposed method forecast shows its superiority compared with others. - Abstract: Energy demand projection is fundamental to rational energy planning formulation. The present study investigates the direct and indirect effects of five factors, namely GDP, population, proportion of industrial, proportion of urban population and coal percentage of total energy consumption on China’s energy demand, implementing a path-coefficient analysis. On this basis, a hybrid algorithm, Particle Swarm Optimization and Genetic Algorithm optimal Energy Demand Estimating (PSO–GA EDE) model, is proposed for China. The coefficients of the three forms of the model (linear, exponential and quadratic model) are optimized by proposed PSO–GA. To obtain a combinational prediction of three forms, a departure coefficient method is applied to get the combinational weights. The results show that the China’s energy demand will be 4.48 billion tce in 2015. Furthermore; the proposed method forecast shows its superiority compared with other single optimization method such as GA, PSO or ACO and multiple linear regressions.

Assessment of end-use electricity consumption and peak demand by Townsville's housing stock

International Nuclear Information System (INIS)

Ren, Zhengen; Paevere, Phillip; Grozev, George; Egan, Stephen; Anticev, Julia

2013-01-01

We have developed a comprehensive model to estimate annual end-use electricity consumption and peak demand of housing stock, considering occupants' use of air conditioning systems and major appliances. The model was applied to analyse private dwellings in Townsville, Australia's largest tropical city. For the financial year (FY) 2010–11 the predicted results agreed with the actual electricity consumption with an error less than 10% for cooling thermostat settings at the standard setting temperature of 26.5 °C and at 1.0 °C higher than the standard setting. The greatest difference in monthly electricity consumption in the summer season between the model and the actual data decreased from 21% to 2% when the thermostat setting was changed from 26.5 °C to 27.5 °C. Our findings also showed that installation of solar panels in Townville houses could reduce electricity demand from the grid and would have a minor impact on the yearly peak demand. A key new feature of the model is that it can be used to predict probability distribution of energy demand considering (a) that appliances may be used randomly and (b) the way people use thermostats. The peak demand for the FY estimated from the probability distribution tracked the actual peak demand at 97% confidence level. - Highlights: • We developed a model to estimate housing stock energy consumption and peak demand. • Appliances used randomly and thermostat settings for space cooling were considered. • On-site installation of solar panels was also considered. • Its' results agree well with the actual electricity consumption and peak demand. • It shows the model could provide the probability distribution of electricity demand

Exact Fill Rates for the (R, S Inventory Control with Discrete Distributed Demands for the Backordering Case

Directory of Open Access Journals (Sweden)

Eugenia BABILONI

2012-01-01

Full Text Available The fill rate is usually computed by using the traditional approach, which calculates it as the complement of the quotient between the expected unfulfilled demand and the expected demand per replenishment cycle, instead of directly the expected fraction of fulfilled demand. Furthermore the available methods to estimate the fill rate apply only under specific demand conditions. This paper shows the research gap regarding the estimation procedures to compute the fill rate and suggests: (i a new exact procedure to compute the traditional approximation for any discrete demand distribution; and (ii a new method to compute the fill rate directly as the fraction of fulfilled demand for any discrete demand distribution. Simulation results show that the latter methods outperform the traditional approach, which underestimates the simulated fill rate, over different demand patterns. This paper focuses on the traditional periodic review, base stock system when backlogged demands are allowed.

Avoiding the conflict: Metacognitive awareness drives the selection of low-demand contexts.

Science.gov (United States)

Desender, Kobe; Buc Calderon, Cristian; Van Opstal, Filip; Van den Bussche, Eva

2017-07-01

Previous research attempted to explain how humans strategically adapt behavior in order to achieve successful task performance. Recently, it has been suggested that 1 potential strategy is to avoid tasks that are too demanding. Here, we report 3 experiments that investigate the empirically neglected role of metacognitive awareness in this process. In these experiments, participants could freely choose between performing a task in either a high-demand or a low-demand context. Using subliminal priming, we ensured that participants were not aware of the visual stimuli creating these different demand contexts. Our results showed that participants who noticed a difference in task difficulty (i.e., metacognitive aware participants) developed a clear preference for the low-demand context. In contrast, participants who experienced no difference in task difficulty (i.e., metacognitive unaware participants) based their choices on variables unrelated to cognitive demand (e.g., the color or location associated with a context), and did not develop a preference for the low-demand context. Crucially, this pattern was found despite identical task performance in both metacognitive awareness groups. A multiple regression approach confirmed that metacognitive awareness was the main factor driving the preference for low-demand contexts. These results argue for an important role of metacognitive awareness in the strategic avoidance of demanding tasks. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Energy demand in the Norwegian building stock. Scenarios on potential reduction

Energy Technology Data Exchange (ETDEWEB)

Sartori, Igor; Hestnes, Anne Grete [Department of Architectural Design, History and Technology, Norwegian University of Science and Technology (NTNU), 7491 Trondheim (Norway); Wachenfeldt, Bjoern Jensen [SINTEF Building and Infrastructure, 7465 Trondheim (Norway)

2009-05-15

A model has been developed for studying the effect of three hypothetical approaches in reducing electricity and energy demand in the Norwegian building stock: wide diffusion of thermal carriers, heat pumps and conservation measures, respectively. Combinations of these are also considered. The model has a demand side perspective, considers both residential and service sectors, and calculates energy flows from net to delivered energy. Energy demand is given by the product of activity and intensity matrices. The activity levels are defined for the stock and the new construction, renovation and demolition flows. The intensity properties are defined in archetypes, and are the result of different energy class and heating carriers share options. The scenarios are shaped by combining the activity flows with different archetypes. The results show that adopting conservation measures on a large scale does allow reducing both electricity and total energy demand from present day levels while the building stock keeps growing. The results also highlight the importance of making a clear distinction between the assumptions on intensity and activity levels. (author)

Energy demand in the Norwegian building stock: Scenarios on potential reduction

Energy Technology Data Exchange (ETDEWEB)

Sartori, Igor [Department of Architectural Design, History and Technology, Norwegian University of Science and Technology (NTNU), 7491 Trondheim (Norway)], E-mail: igor.sartori@sintef.no; Wachenfeldt, Bjorn Jensen [SINTEF Building and Infrastructure, 7465 Trondheim (Norway); Hestnes, Anne Grete [Department of Architectural Design, History and Technology, Norwegian University of Science and Technology (NTNU), 7491 Trondheim (Norway)

2009-05-15

A model has been developed for studying the effect of three hypothetical approaches in reducing electricity and energy demand in the Norwegian building stock: wide diffusion of thermal carriers, heat pumps and conservation measures, respectively. Combinations of these are also considered. The model has a demand side perspective, considers both residential and service sectors, and calculates energy flows from net to delivered energy. Energy demand is given by the product of activity and intensity matrices. The activity levels are defined for the stock and the new construction, renovation and demolition flows. The intensity properties are defined in archetypes, and are the result of different energy class and heating carriers share options. The scenarios are shaped by combining the activity flows with different archetypes. The results show that adopting conservation measures on a large scale does allow reducing both electricity and total energy demand from present day levels while the building stock keeps growing. The results also highlight the importance of making a clear distinction between the assumptions on intensity and activity levels.

Energy demand in the Norwegian building stock: Scenarios on potential reduction

International Nuclear Information System (INIS)

Sartori, Igor; Wachenfeldt, Bjorn Jensen; Hestnes, Anne Grete

2009-01-01

A model has been developed for studying the effect of three hypothetical approaches in reducing electricity and energy demand in the Norwegian building stock: wide diffusion of thermal carriers, heat pumps and conservation measures, respectively. Combinations of these are also considered. The model has a demand side perspective, considers both residential and service sectors, and calculates energy flows from net to delivered energy. Energy demand is given by the product of activity and intensity matrices. The activity levels are defined for the stock and the new construction, renovation and demolition flows. The intensity properties are defined in archetypes, and are the result of different energy class and heating carriers share options. The scenarios are shaped by combining the activity flows with different archetypes. The results show that adopting conservation measures on a large scale does allow reducing both electricity and total energy demand from present day levels while the building stock keeps growing. The results also highlight the importance of making a clear distinction between the assumptions on intensity and activity levels.

Consumer Demand for Major Foods in Egypt

OpenAIRE

Basem Fayaad; Stanley R. Johnson; Mohamed El-Khishin

1995-01-01

This study provides information on the structure of the consumer demand for major foods in Egypt. The information is in the form of key parameters for consumer demand systems. The modern theory of consumer behavior is the basis for estimating systems of demand equations. These systems yield estimates of own- and cross-price elasticities. The Linear Almost Ideal Demand System (LAIDS) model is applied in estimating a system of demand equations for food commodities. A full demand matrix results ...

Uncertain socioeconomic projections used in travel demand and emissions models: could plausible errors result in air quality nonconformity?

International Nuclear Information System (INIS)

Rodier, C.J.; Johnston, R.A.

2002-01-01

A sensitivity analysis of plausible errors in population, employment, fuel price, and income projections is conducted using the travel demand and emissions models of the Sacramento, CA, USA, region for their transportation plan. The results of the analyses indicate that plausible error ranges for household income and fuel prices are not a significant source of uncertainty with respect to the region's travel demand and emissions projections. However, plausible errors in population and employment projections (within approximately one standard deviation) may result in the region's transportation plan not meeting the conformity test for nitrogens of oxides (NO x ) in the year 2005 (i.e., an approximately 16% probability). This outcome is also possible in the year 2015 but less likely (within approximately two standard deviations or a 2.5% probability). Errors in socioeconomic projections are only one of many sources of error in travel demand and emissions models. These results have several policy implications. First, regions like Sacramento that meet their conformity tests by a very small margin should rethink new highway investment and consider contingency transportation plans that incorporate more aggressive emissions reduction policies. Second, regional transportation planning agencies should conduct sensitivity analyses as part of their conformity analysis to make explicit significant uncertainties in the methods and to identify the probability of their transportation plan not conforming. Third, the US Environmental Protection Agency (EPA) should clarify the interpretation of ''demonstrate'' conformity of transportation plans; that is, specify the level of certainty that it considers a sufficient demonstration of conformity. (author)

Climate change and energy demand

International Nuclear Information System (INIS)

Hengeveld, H.G.

1991-01-01

Climate and weather events affect energy demand in most economic sectors. Linear relationships exist between consumption and heating degree days, and peak electricity demand increases significantly during heat waves. The relative magnitudes of demand changes for a two times carbon dioxide concentration scenario are tabulated, illustrating heating degree days and cooling degree days for 5 Prairie locations. Irrigation, water management, crop seeding and harvesting and weed control are examples of climate-dependent agricultural activities involving significant energy use. The variability of summer season liquid fuel use in the agricultural sector in the Prairie provinces from 1984-1989 shows a relationship between agricultural energy use and regional climate fluctuations. 4 refs., 2 figs., 1 tab

Electricity demand for South Korean residential sector

International Nuclear Information System (INIS)

Sa'ad, Suleiman

2009-01-01

This study estimates the electricity demand function for the residential sector of South Korea with the aim of examining the effects of improved energy efficiency, structural factors and household lifestyles on electricity consumption. In the study, time series data for the period from 1973 to 2007 is used in a structural time series model to estimate the long-term price and income elasticities and annual growth of underlying energy demand trend (UEDT) at the end of the estimation period. The result shows a long-term income elasticity of 1.33 and a long-term price elasticity of -0.27% with -0.93% as the percentage growth of UEDT at the end of the estimation period. This result suggests that, in order to encourage energy efficiency in the residential sector, the government should complement the market based pricing policies with non-market policies such as minimum energy efficiency standards and public enlightenment.

PENGARUH JOB DEMANDS, JOB RESOURCES DAN PERSONAL RESOURCES TERHADAP WORK ENGAGEMENT

OpenAIRE

Diah Restu Ayu; M. Syamsul Maarif; Anggraini Sukmawati

2015-01-01

The purposes of this study were to identify the influence of job demands, job resources and personal resources toward work engagement, define the best predictors of work engagement and the influence of work engagement towards turnover intention. Structural equation modeling was used in this research to estimate the influence of variables simultaneously. This research was conducted to 116 samples of manufacturing employees. The results showed that job demands have direct effect to work engagem...

Demand, capacity, and access of the outpatient clinic: A framework for analysis and improvement.

Science.gov (United States)

van Bussel, Erik Martijn; van der Voort, Marc Boudewijn Victor Rouppe; Wessel, Ronald N; van Merode, Godefridus G

2018-06-01

While theoretical frameworks for optimization of the outpatient processes are abundant, practical step-by-step analyses to give leads for improvement, to forecast capacity, and to support decision making are sparse. This article demonstrates how to evaluate and optimize the triad of demand, (future) capacity, and access time of the outpatient clinic using a structured six-step method. All individual logistical patient data of an orthopaedic outpatient clinic of one complete year were analysed using a 6-step method to evaluate demand, supply, and access time. Trends in the data were retrospectively analysed and evaluated for potential improvements. A model for decision making was tested. Both the analysis of the method and actual results were considered as main outcomes. More than 25 000 appointments were analysed. The 6-step method showed to be sufficient to result in valuable insights and leads for improvement. While the overall match between demand and capacity was considered adequate, the variability in capacity was much higher than in demand, thereby leading to delays in access time. Holidays and subsequent weeks showed to be of great influence for demand, capacity, and access time. Using the six-step method, several unfavourable characteristics of the outpatient clinic were revealed and a better match between demand, supply, and access time could have been reached with only minor adjustments. Last, a clinic specific prediction and decision model for demand and capacity was made using the 6-step method. The 6-step analysis can successfully be applied to redesign and improve the outpatient health care process. The results of the analysis showed that national holidays and variability in demand and capacity have a big influence on the outpatient clinic. Using the 6-step method, practical improvements in outpatient logistics were easily found and leads for future decision making were contrived. © 2018 The Authors Journal of Evaluation in Clinical Practice

Flexible Demand Management under Time-Varying Prices

Science.gov (United States)

Liang, Yong

optimization problem when the objective is to minimize the expected total cost and discomfort, then since the decision maker is likely to be risk-averse, and she wants to protect herself from price spikes, we study the robust optimization problem to address the risk-aversion of the decision maker. We conduct numerical studies to evaluate the price of robustness. Next, we present a detailed model that manages multiple types of flexible demand in the absence of knowledge regarding the distributions of related stochastic processes. Specifically, we consider the case in which time-varying prices with general structures are offered to users, and an energy management system for each household makes optimal energy usage, storage, and trading decisions according to the preferences of users. Because of the uncertainties associated with electricity prices, local generation, and the arrival processes of demand, we formulate a stochastic dynamic programming model, and outline a novel and tractable ADP approach to overcome the curses of dimensionality. Then, we perform numerical studies, whose results demonstrate the effectiveness of the ADP approach. At last, we propose another approximation approach based on Q-learning. In addition, we also develop another decentralization-based heuristic. Both the Q-learning approach and the heuristic make necessary assumptions on the knowledge of information, and each of them has unique advantages. We conduct numerical studies on a testing problem. The simulation results show that both the Q-learning and the decentralization based heuristic approaches work well. Lastly, we conclude the paper with some discussions on future extension directions.

The impact of future energy demand on renewable energy production – Case of Norway

International Nuclear Information System (INIS)

Rosenberg, Eva; Lind, Arne; Espegren, Kari Aamodt

2013-01-01

Projections of energy demand are an important part of analyses of policies to promote conservation, efficiency, technology implementation and renewable energy production. The development of energy demand is a key driver of the future energy system. This paper presents long-term projections of the Norwegian energy demand as a two-step methodology of first using activities and intensities to calculate a demand of energy services, and secondly use this as input to the energy system model TIMES-Norway to optimize the Norwegian energy system. Long-term energy demand projections are uncertain and the purpose of this paper is to illustrate the impact of different projections on the energy system. The results of the analyses show that decreased energy demand results in a higher renewable fraction compared to an increased demand, and the renewable energy production increases with increased energy demand. The most profitable solution to cover increased demand is to increase the use of bio energy and to implement energy efficiency measures. To increase the wind power production, an increased renewable target or higher electricity export prices have to be fulfilled, in combination with more electricity export. - Highlights: • Projections to 2050 of Norwegian energy demand services, carriers and technologies. • Energy demand services calculated based on intensities and activities. • Energy carriers and technologies analysed by TIMES-Norway. • High renewable target results in more wind power production and electricity export. • Increased energy efficiency is important for a high renewable fraction

Endogenous Money Supply and Money Demand

OpenAIRE

Woon Gyu Choi; Seonghwan Oh

2000-01-01

This paper explores the behavior of money demand by explicitly accounting for the money supply endogeneity arising from endogenous monetary policy and financial innovations. Our theoretical analysis indicates that money supply factors matter in the money demand function when the money supply partially responds to money demand. Our empirical results with U.S. data provide strong evidence for the relevance of the policy stance to the demand for MI under a regime in which monetary policy is subs...

Solar + Storage Synergies for Managing Commercial-Customer Demand Charges

Energy Technology Data Exchange (ETDEWEB)

Gagnon, Pieter J. [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Govindarajan, Anand [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Bird, Lori A. [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Barbose, Galen [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Darghouth, Naim [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Mills, Andrew [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2017-10-24

We study the synergies between behind-the-meter solar and storage in reducing commercial-customer demand charges. This follows two previous studies that examined demand charge savings for stand-alone solar in both the residential and commercial sectors. In this study we show that solar and storage show consistent synergies for demand charge management, that the magnitude of reductions are highly customer-specific, and that the magnitude of savings is influenced by the design of the electricity tariff.

Enhancing perceptual and attentional skills requires common demands between the action video games and transfer tasks

Science.gov (United States)

Oei, Adam C.; Patterson, Michael D.

2015-01-01

Despite increasing evidence that shows action video game play improves perceptual and cognitive skills, the mechanisms of transfer are not well-understood. In line with previous work, we suggest that transfer is dependent upon common demands between the game and transfer task. In the current study, participants played one of four action games with varying speed, visual, and attentional demands for 20 h. We examined whether training enhanced performance for attentional blink, selective attention, attending to multiple items, visual search and auditory detection. Non-gamers who played the game (Modern Combat) with the highest demands showed transfer to tasks of attentional blink and attending to multiple items. The game (MGS Touch) with fewer attentional demands also decreased attentional blink, but to a lesser degree. Other games failed to show transfer, despite having many action game characteristics but at a reduced intensity. The results support the common demands hypothesis. PMID:25713551

Enhancing perceptual and attentional skills requires common demands between the action video games and transfer tasks.

Science.gov (United States)

Oei, Adam C; Patterson, Michael D

2015-01-01

Despite increasing evidence that shows action video game play improves perceptual and cognitive skills, the mechanisms of transfer are not well-understood. In line with previous work, we suggest that transfer is dependent upon common demands between the game and transfer task. In the current study, participants played one of four action games with varying speed, visual, and attentional demands for 20 h. We examined whether training enhanced performance for attentional blink, selective attention, attending to multiple items, visual search and auditory detection. Non-gamers who played the game (Modern Combat) with the highest demands showed transfer to tasks of attentional blink and attending to multiple items. The game (MGS Touch) with fewer attentional demands also decreased attentional blink, but to a lesser degree. Other games failed to show transfer, despite having many action game characteristics but at a reduced intensity. The results support the common demands hypothesis.

Enhancing perceptual and attentional skills requires common demands between the action video games and transfer tasks

Directory of Open Access Journals (Sweden)

Adam C Oei

2015-02-01

Full Text Available Despite increasing evidence that shows action video game play improves perceptual and cognitive skills, the mechanisms of transfer are not well understood. In line with previous work, we suggest that transfer is dependent upon common demands between the game and transfer task. In the current study, participants played one of four action games with varying speed, visual, and attentional demands for twenty hours. We examined whether training enhanced performance for attentional blink, selective attention, attending to multiple items, visual search and auditory detection. Non-gamers who played the game (Modern Combat with the highest demands showed transfer to tasks of attentional blink and attending to multiple items. The game (MGS Touch with fewer attentional demands also decreased attentional blink, but to a lesser degree. Other games failed to show transfer, despite having many action game characteristics but at a reduced intensity. The results support the common demands hypothesis

Energy supply and demand in Canada and export demand for Canadian energy, 1966--1990

Energy Technology Data Exchange (ETDEWEB)

1969-01-01

This report presents the results of a National Energy Board staff study of energy supply and demand in Canada to 1990. The study covers all forms of energy in Canada, and probable sources of supply for serving both indigenous and export demand for Canadian energy. Energy demand by market sector (residential and commercial, industrial, and transportation) is discussed in Chapters III, IV and V, respectively. Chapters VI, VII, VIII, and IX deal with supply prospects for Canadian petroleum, natural gas, coal, and electricity serving indigenous and export markets. A summary of the report is contained in Chapter II. Appendix A reviews general assumptions including those relating to population and household growth. Appendix B summarizes the methodology used for estimating residential energy demand, automobile transportation energy demand, and electricity supply. Appendix C includes a number of tables which provide detailed information. A list of definitions and abbreviations follows the Table of Contents.

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

International Nuclear Information System (INIS)

Chassin, David P.; Rondeau, Daniel

2016-01-01

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

Fuel demand in Brazil in a dynamic panel data approach

International Nuclear Information System (INIS)

Santos, Gervásio F.

2013-01-01

The purpose of this paper is to evaluate the sensitivity of fuel consumers regarding price and income, taking recent changes in the Brazilian fuel market into account. In this market, new market rules, energy policy towards fuel diversification and introduction of flex-fuel engines have determined fuel competition among gasoline, ethanol and compressed natural gas. Using a dynamic panel data model, demand equations for these three fuels are econometrically estimated to obtain consumer adjustment coefficients, price, cross-price and income elasticities in the short and long-run. In addition, the effect of the introduction of flex-fuel engines in the market and the rationality of consumers towards efficiency constraints of the engines were tested. Apart from considerable competition, results show that the dynamics of the Brazilian fuel market revolves around ethanol instead of gasoline. While demands for gasoline and natural gas are inelastic to price, demand for ethanol is elastic in Brazil. Furthermore, after the introduction of the flex-fuel technology the sensitivity of consumers to fuel prices changed, and ethanol consumers take efficiency constrains into account when ethanol prices reach the threshold of 70% of gasoline prices. - Highlights: ► Fuel demand in Brazil is evaluated, considering the changes in the fuel market. ► A dynamic panel data model is used to fit demand equations for fuels. ► Adjustment coefficients, price, cross-price and income elasticities are estimated. ► The impact of flex-fuel technology on the consumer behavior is tested. ► The results showed that the dynamic of the fuel market revolves around ethanol. ► The flex-fuel technology increased the competition among fuels

Ethanol demand in Brazil: Regional approach

International Nuclear Information System (INIS)

Freitas, Luciano Charlita de; Kaneko, Shinji

2011-01-01

Successive studies attempting to clarify national aspects of ethanol demand have assisted policy makers and producers in defining strategies, but little information is available on the dynamic of regional ethanol markets. This study aims to analyze the characteristics of ethanol demand at the regional level taking into account the peculiarities of the developed center-south and the developing north-northeast regions. Regional ethanol demand is evaluated based on a set of market variables that include ethanol price, consumer's income, vehicle stock and prices of substitute fuels; i.e., gasoline and natural gas. A panel cointegration analysis with monthly observations from January 2003 to April 2010 is employed to estimate the long-run demand elasticity. The results reveal that the demand for ethanol in Brazil differs between regions. While in the center-south region the price elasticity for both ethanol and alternative fuels is high, consumption in the north-northeast is more sensitive to changes in the stock of the ethanol-powered fleet and income. These, among other evidences, suggest that the pattern of ethanol demand in the center-south region most closely resembles that in developed nations, while the pattern of demand in the north-northeast most closely resembles that in developing nations. - Research highlights: → Article consists of a first insight on regional demand for ethanol in Brazil. → It proposes a model with multiple fuels, i.e., hydrous ethanol, gasohol and natural gas. → Results evidence that figures for regional demand for ethanol differ amongst regions and with values reported for national demand. → Elasticities for the center-south keep similarities to patterns for fuel demand in developed nations while coefficients for the north-northeast are aligned to patterns on developing countries.

Ethanol demand in Brazil: Regional approach

Energy Technology Data Exchange (ETDEWEB)

Freitas, Luciano Charlita de, E-mail: lucianofreitas@hiroshima-u.ac.j [Graduate School for International Development and Cooperation, Development Policy, Hiroshima University 1-5-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8529 (Japan); Kaneko, Shinji [Graduate School for International Development and Cooperation, Development Policy, Hiroshima University 1-5-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8529 (Japan)

2011-05-15

Successive studies attempting to clarify national aspects of ethanol demand have assisted policy makers and producers in defining strategies, but little information is available on the dynamic of regional ethanol markets. This study aims to analyze the characteristics of ethanol demand at the regional level taking into account the peculiarities of the developed center-south and the developing north-northeast regions. Regional ethanol demand is evaluated based on a set of market variables that include ethanol price, consumer's income, vehicle stock and prices of substitute fuels; i.e., gasoline and natural gas. A panel cointegration analysis with monthly observations from January 2003 to April 2010 is employed to estimate the long-run demand elasticity. The results reveal that the demand for ethanol in Brazil differs between regions. While in the center-south region the price elasticity for both ethanol and alternative fuels is high, consumption in the north-northeast is more sensitive to changes in the stock of the ethanol-powered fleet and income. These, among other evidences, suggest that the pattern of ethanol demand in the center-south region most closely resembles that in developed nations, while the pattern of demand in the north-northeast most closely resembles that in developing nations. - Research highlights: {yields} Article consists of a first insight on regional demand for ethanol in Brazil. {yields} It proposes a model with multiple fuels, i.e., hydrous ethanol, gasohol and natural gas. {yields} Results evidence that figures for regional demand for ethanol differ amongst regions and with values reported for national demand. {yields} Elasticities for the center-south keep similarities to patterns for fuel demand in developed nations while coefficients for the north-northeast are aligned to patterns on developing countries.

HEDONIC DEMAND ANALYSIS FOR BEEF IN BENIN METROPOLIS

African Journals Online (AJOL)

BIUAGRIC2

2013-02-11

Feb 11, 2013 ... implicit demand for beef within the framework of a hedonic analysis, and the implicit or shadow price of beef were examined. Primary data ... results of the Hedonic analysis showed that, with an average unit price of N836.57 for beef, a consumer is strongly willing to pay ... method and strategies. Lancaster ...

PREDICTING DEMAND FOR COTTON YARNS

Directory of Open Access Journals (Sweden)

SALAS-MOLINA Francisco

2017-05-01

Full Text Available Predicting demand for fashion products is crucial for textile manufacturers. In an attempt to both avoid out-of-stocks and minimize holding costs, different forecasting techniques are used by production managers. Both linear and non-linear time-series analysis techniques are suitable options for forecasting purposes. However, demand for fashion products presents a number of particular characteristics such as short life-cycles, short selling seasons, high impulse purchasing, high volatility, low predictability, tremendous product variety and a high number of stock-keeping-units. In this paper, we focus on predicting demand for cotton yarns using a non-linear forecasting technique that has been fruitfully used in many areas, namely, random forests. To this end, we first identify a number of explanatory variables to be used as a key input to forecasting using random forests. We consider explanatory variables usually labeled either as causal variables, when some correlation is expected between them and the forecasted variable, or as time-series features, when extracted from time-related attributes such as seasonality. Next, we evaluate the predictive power of each variable by means of out-of-sample accuracy measurement. We experiment on a real data set from a textile company in Spain. The numerical results show that simple time-series features present more predictive ability than other more sophisticated explanatory variables.

Daily job demands and employee work engagement: The role of daily transformational leadership behavior.

Science.gov (United States)

Breevaart, Kimberley; Bakker, Arnold B

2018-07-01

Using job demands-resources (JD-R) theory, the present study integrates the challenge stressor-hindrance stressor framework and leadership theory to investigate the relationship between daily transformational leadership behavior and employee work engagement. We hypothesized that daily transformational leadership behavior (a) sustains employee work engagement on days characterized by high challenge job demands, and (b) protects work engagement on days characterized by high hindrance job demands. Teachers filled out a short online questionnaire at the end of each workday during a 2-week period (N = 271 × 5.68 days = 1539). Results of latent moderated structural equation modeling showed that teachers' daily challenge demands (workload and cognitive demands) had a positive relationship with work engagement on the days transformational leadership was high (vs. low). In addition, teachers' daily hindrance demands (role-conflict, but not family to work conflict) had a negative relationship with work engagement on the days transformational leadership was low (vs. high). These findings show that the function of transformational leadership behavior changes from day to day, and depends on the type of job demand. We discuss the practical and theoretical implications of these findings. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Spanish version of Bus Drivers' Job Demands Scale (BDJD-24).

Science.gov (United States)

Boada-Grau, Joan; Prizmic-Kuzmica, Aldo-Javier; González-Fernández, Marcos-David; Vigil-Colet, Andreu

2013-01-01

Karasek and Theorell's Job Demands-Control Model argues that adverse health-related outcomes, both psychological and physiological, arise from a combination of high job demand and a low level of job control. The objective was to adapt Meijman and Kompier's Bus Drivers' Job Demands Scale (BDJD-24), which enables us to assess the job demands of bus drivers, to Spanish. The final version of the Spanish adaptation was applied to a sample made up of 287 bus drivers living in Spain (80.1% men and 19.9% women), whose average age was 40.44 (SD= 11.78). The results yielded a three-factor structure for the scale used: Time Pressure, Safety, and Passengers. These findings confirm that the Spanish version replicates the factor structure of the original English scale. The reliability of the three subscales was acceptable, ranging from .75 to .84. Furthermore, the subscales were also related to different external correlates and to other scales and showed good convergent and criterion validity. The present instrument can be used to evaluate job demands of bus drivers, as its psychometrics are substantially sound.

Bayesian Analysis of Demand Elasticity in the Italian Electricity Market

Directory of Open Access Journals (Sweden)

Maria Chiara D'Errico

2015-09-01

Full Text Available The liberalization of the Italian electricity market is a decade old. Within these last ten years, the supply side has been extensively analyzed, but not the demand side. The aim of this paper is to provide a new method for estimation of the demand elasticity, based on Bayesian methods applied to the Italian electricity market. We used individual demand bids data in the day-ahead market in the Italian Power Exchange (IPEX, for 2011, in order to construct an aggregate demand function at the hourly level. We took into account the existence of both elastic and inelastic bidders on the demand side. The empirical results show that elasticity varies significantly during the day and across periods of the year. In addition, the elasticity hourly distribution is clearly skewed and more so in the daily hours. The Bayesian method is a useful tool for policy-making, insofar as the regulator can start with a priori historical information on market behavior and estimate actual market outcomes in response to new policy actions.

Intercity Travel Demand Analysis Model

Directory of Open Access Journals (Sweden)

Ming Lu

2014-01-01

Full Text Available It is well known that intercity travel is an important component of travel demand which belongs to short distance corridor travel. The conventional four-step method is no longer suitable for short distance corridor travel demand analysis for the time spent on urban traffic has a great impact on traveler's main mode choice. To solve this problem, the author studied the existing intercity travel demand analysis model, then improved it based on the study, and finally established a combined model of main mode choice and access mode choice. At last, an integrated multilevel nested logit model structure system was built. The model system includes trip generation, destination choice, and mode-route choice based on multinomial logit model, and it achieved linkage and feedback of each part through logsum variable. This model was applied in Shenzhen intercity railway passenger demand forecast in 2010 as a case study. As a result, the forecast results were consistent with the actuality. The model's correctness and feasibility were verified.

Possible Demands for Eastern Hardwoods Resulting from Harvest Restrictions in the Pacific

Science.gov (United States)

Janice K. Wiedenbeck; Philip A. Araman

1993-01-01

Efforts to conserve the habitat of the northern spotted owl in the Pacific Northwest have placed softwood timber supplies under a great deal of pressure and driven up the price of softwood lumber. Hardwoods could meet some of the demand for products that have previously been manufactured from softwood species. Hardwood structural lumber may soon become an economically...

Effects of Nurses' Perceptions of Actual and Demanded Competence on Turnover Intentions.

Science.gov (United States)

Takase, Miyuki; Yamamoto, Masako; Sato, Yoko; Imai, Takiko; Kawamoto, Mitsuko

2017-10-01

With the growing focus on continuous professional development, demands placed on nurses to uphold nursing competence have been increasing. This study examined how nurses with different lengths of clinical experience perceived the relationship between their actual competence and the competence they felt was demanded of them, and how this relationship was related to their turnover intentions. Survey questionnaires were distributed to 1,377 nurses, of whom 765 returned usable completed forms. The results showed that across all the groups of clinical experience, nurses perceived the demanded competence levels to be higher than their actual competence levels. However, turnover intentions were not related to nurses' perceptions of demanded competence and were negatively related to perceptions of actual competence. The levels of competence demanded should not be considered as threats for nurses. Improving nurses' competence may reduce their turnover intentions.

Electricity demand for South Korean residential sector

Energy Technology Data Exchange (ETDEWEB)

Sa' ad, Suleiman [Surrey Energy Economics Centre (SEEC), Department of Economics, University of Surrey, Guildford, Surrey GU2 7XH (United Kingdom)

2009-12-15

This study estimates the electricity demand function for the residential sector of South Korea with the aim of examining the effects of improved energy efficiency, structural factors and household lifestyles on electricity consumption. In the study, time series data for the period from 1973 to 2007 is used in a structural time series model to estimate the long-term price and income elasticities and annual growth of underlying energy demand trend (UEDT) at the end of the estimation period. The result shows a long-term income elasticity of 1.33 and a long-term price elasticity of -0.27% with -0.93% as the percentage growth of UEDT at the end of the estimation period. This result suggests that, in order to encourage energy efficiency in the residential sector, the government should complement the market based pricing policies with non-market policies such as minimum energy efficiency standards and public enlightenment. (author)

Task demand, task management, and teamwork

Energy Technology Data Exchange (ETDEWEB)

Braarud, Per Oeivind; Brendryen, Haavar

2001-03-15

The current approach to mental workload assessment in process control was evaluated in 3 previous HAMMLAB studies, by analysing the relationship between workload related measures and performance. The results showed that subjective task complexity rating was related to team's control room performance, that mental effort (NASA-TLX) was weakly related to performance, and that overall activity level was unrelated to performance. The results support the argument that general cognitive measures, i.e., mental workload, are weakly related to performance in the process control domain. This implies that other workload concepts than general mental workload are needed for valid assessment of human reliability and for valid assessment of control room configurations. An assessment of task load in process control suggested that how effort is used to handle task demand is more important then the level of effort invested to solve the task. The report suggests two main workload related concepts with a potential as performance predictors in process control: task requirements, and the work style describing how effort is invested to solve the task. The task requirements are seen as composed of individual task demand and team demand. In a similar way work style are seen as composed of individual task management and teamwork style. A framework for the development of the concepts is suggested based on a literature review and experiences from HAMMLAB research. It is suggested that operational definitions of workload concepts should be based on observable control room behaviour, to assure a potential for developing performance-shaping factors. Finally an explorative analysis of teamwork measures and performance in one study indicated that teamwork concepts are related to performance. This lends support to the suggested development of team demand and teamwork style as elements of a framework for the analysis of workload in process control. (Author)

Aggregated Demand Modelling Including Distributed Generation, Storage and Demand Response

OpenAIRE

Marzooghi, Hesamoddin; Hill, David J.; Verbic, Gregor

2014-01-01

It is anticipated that penetration of renewable energy sources (RESs) in power systems will increase further in the next decades mainly due to environmental issues. In the long term of several decades, which we refer to in terms of the future grid (FG), balancing between supply and demand will become dependent on demand actions including demand response (DR) and energy storage. So far, FG feasibility studies have not considered these new demand-side developments for modelling future demand. I...

Supplementing energy demand of rural households in Bangladesh through appropriate biogas technology

DEFF Research Database (Denmark)

Ashekuzzaman, S.M.; Badruzzaman, A.B.M.; Rafiqul Hoque, A.T.M.

2010-01-01

This paper has sought to show the potential of energy recovery from rurally available agro and household organic wastes and thus, the possible impact on supplementing energy demand, reducing deforestation, and replacing fossil fuel as well as avoided greenhouse gases. Results show that co......-digestion of a wide range of manure, crop residues and household wastes with cow manure was successful to produce increased gas yield than what would be if cow dung is digested separately and the energy value from this can supplement 57–79% of the rural energy demand, depending on the methane yield from organic waste...

Analysis of food demand among rural households in Kwara State ...

African Journals Online (AJOL)

Analysis of food demand among rural households in Kwara State, North Central ... Nigerian Journal of Technological Research ... Contrary to the law of demand, this study shows that the demand for animal products and fats/oil increased with ...

The power to choose. Demand response in liberalized electricity markets

International Nuclear Information System (INIS)

2003-01-01

Highly volatile electricity prices are becoming a more frequent and unwanted characteristic of modern electricity wholesale markets. But low demand elasticity, mainly the result of a lack of incentives and consumers' inability to control demand, means that consumer behaviour is not reflected in the cost of energy. This study analyses the impact of price-responsive demand and shows how pricing, policy and technology can be used to inform consumer behaviour and choice. Informed choice and market-based valuation of electricity supply will ensure liberalized markets are competitive, efficient, less volatile and able to provide long term security of supply. Significant benefits will occur even if only 5% of customers become responsive to price-incentives and information. And customers will respond to well designed programs, thereby developing a role in ensuring efficient price formulation for electricity. This study analyses the economic, efficiency and security benefits and identifies the changes in electricity tariffs and the network infrastructure needed to achieve greater demand response

Designing container shipping network under changing demand and freight rates

Directory of Open Access Journals (Sweden)

C. Chen

2010-03-01

Full Text Available This paper focuses on the optimization of container shipping network and its operations under changing cargo demand and freight rates. The problem is formulated as a mixed integer non-linear programming problem (MINP with an objective of maximizing the average unit ship-slot profit at three stages using analytical methodology. The issues such as empty container repositioning, ship-slot allocating, ship sizing, and container configuration are simultaneously considered based on a series of the matrices of demand for a year. To solve the model, a bi-level genetic algorithm based method is proposed. Finally, numerical experiments are provided to illustrate the validity of the proposed model and algorithms. The obtained results show that the suggested model can provide a more realistic solution to the issues on the basis of changing demand and freight rates and arrange a more effective approach to the optimization of container shipping network structures and operations than does the model based on the average demand.

A Framework for Sustainable Urban Water Management through Demand and Supply Forecasting: The Case of Istanbul

Directory of Open Access Journals (Sweden)

Murat Yalçıntaş

2015-08-01

Full Text Available The metropolitan city of Istanbul is becoming overcrowded and the demand for clean water is steeply rising in the city. The use of analytical approaches has become more and more critical for forecasting the water supply and demand balance in the long run. In this research, Istanbul’s water supply and demand data is collected for the period during 2006 and 2014. Then, using an autoregressive integrated moving average (ARIMA model, the time series water supply and demand forecasting model is constructed for the period between 2015 and 2018. Three important sustainability metrics such as water loss to supply ratio, water loss to demand ratio, and water loss to residential demand ratio are also presented. The findings show that residential water demand is responsible for nearly 80% of total water use and the consumption categories including commercial, industrial, agriculture, outdoor, and others have a lower share in total water demand. The results also show that there is a considerable water loss in the water distribution system which requires significant investments on the water supply networks. Furthermore, the forecasting results indicated that pipeline projects will be critical in the near future due to expected increases in the total water demand of Istanbul. The authors suggest that sustainable management of water can be achieved by reducing the residential water use through the use of water efficient technologies in households and reduction in water supply loss through investments on distribution infrastructure.

Interaction effects among multiple job demands: an examination of healthcare workers across different contexts.

Science.gov (United States)

Jimmieson, Nerina L; Tucker, Michelle K; Walsh, Alexandra J

2017-05-01

Simultaneous exposure to time, cognitive, and emotional demands is a feature of the work environment for healthcare workers, yet effects of these common stressors in combination are not well established. Survey data were collected from 125 hospital employees (Sample 1, Study 1), 93 ambulance service employees (Sample 2, Study 1), and 380 aged care/disability workers (Study 2). Hierarchical multiple regressions were conducted. In Sample 1, high cognitive demand exacerbated high emotional demand on psychological strain and job burnout, whereas the negative effect of high emotional demand was not present at low cognitive demand. In Sample 2, a similar pattern between emotional demand and time demand on stress-remedial intentions was observed. In Study 2, emotional demand × time demand and time demand × cognitive demand interactions again revealed that high levels of two demands were stress-exacerbating and low levels of one demand neutralized the other. A three-way interaction on job satisfaction showed the negative impact of emotional demand was exacerbated when both time and cognitive demands were high, creating a "triple disadvantage" of job demands. The results demonstrate that reducing some job demands helps attenuate the stressful effects of other job demands on different employee outcomes.

Electricity demand in Tunisia

International Nuclear Information System (INIS)

Gam, Imen; Ben Rejeb, Jaleleddine

2012-01-01

This paper examines the global electricity demand in Tunisia as a function of gross domestic product in constant price, the degree of urbanization, the average annual temperature, and the real electricity price per Kwh. This demand will be examined employing annual data over a period spanning almost thirty one years from 1976 to 2006. A long run relationship between the variables under consideration is determined using the Vector Autoregressive Regression. The empirical results suggest that the electricity demand in Tunisia is sensitive to its past value, any changes in gross domestic product and electricity price. The electricity price effects have a negative impact on long-run electricity consumption. However, the gross domestic product and the past value of electricity consumption have a positive effect. Moreover, the causality test reveals a unidirectional relationship between price and electricity consumption. Our empirical findings are effective to policy makers to maintain the electricity consumption in Tunisia by using the appropriate strategy. - Highlights: ► This paper examined the electricity demand in Tunisia in the long-run. ► The empirical analysis revealed that in the long-run the electricity demand is affected by changes in its past value, GDP in constant price and real electricity price. ► There is a unidirectional relationship between price and electricity consumption, that is to say, that the electricity price causes the consumption. ► Those results suggest that a pricing policy can be an effective instrument to rationalize the electricity consumption in Tunisia in the long-run.

Update on Canadian energy supply and demand report, 1998-2025 : summary of results from Round One

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-10-05

The National Energy Board is required to periodically review the outlook of Canadian energy supply and demand for major energy commodities including oil, natural gas and electricity. The National Energy Board undertook a first round of consultations between April 15 and May 1, to seek input regarding Canadian energy supply and demand to 2025. The topics discussed at Round One of these consultations were: (1) oil prices, (2) macroeconomics, (3) energy demand, (4) electricity, (5) coal, (6) crude oil and bitumen resources, (7) natural gas and natural gas liquids, (8) alternative and renewable fuels, (9) emissions, and (10) cases and sensitivities. The comments received on each topic and the Board`s recommendations were presented. A second round of consultation will be held early in 1999.

Assessment of demand for natural gas from the electricity sector in India

DEFF Research Database (Denmark)

Shukla, P.R.; Dhar, Subash; Victor, David G.

2009-01-01

Electricity sector is among the key users of natural gas. The sustained electricity deficit and environment policies have added to an already rising demand for gas. This paper tries to understand gas demand in future from electricity sector. This paper models the future demand for gas in India from...... the electricity sector under alternative scenarios for the period 2005–2025, using bottom-up ANSWER MARKAL model. The scenarios are differentiated by alternate economic growth projections and policies related to coal reforms, infrastructure choices and local environment. The results across scenarios show that gas...... competes with coal as a base-load option if price difference is below US $ 4 per MBtu. At higher price difference gas penetrates only the peak power market. Gas demand is lower in the high economic growth scenario, since electricity sector is more flexible in substitution of primary energy. Gas demand...

Redesign of a supply network by considering stochastic demand

Directory of Open Access Journals (Sweden)

Juan Camilo Paz

2015-09-01

Full Text Available This paper presents the problem of redesigning a supply network of large scale by considering variability of the demand. The central problematic takes root in determining strategic decisions of closing and adjusting of capacity of some network echelons and the tactical decisions concerning to the distribution channels used for transporting products. We have formulated a deterministic Mixed Integer Linear Programming Model (MILP and a stochastic MILP model (SMILP whose objective functions are the maximization of the EBITDA (Earnings before Interest, Taxes, Depreciation and Amortization. The decisions of Network Design on stochastic model as capacities, number of warehouses in operation, material and product flows between echelons, are determined in a single stage by defining an objective function that penalizes unsatisfied demand and surplus of demand due to demand changes. The solution strategy adopted for the stochastic model is a scheme denominated as Sample Average Approximation (SAA. The model is based on the case of a Colombian company dedicated to production and marketing of foodstuffs and supplies for the bakery industry. The results show that the proposed methodology was a solid reference for decision support regarding to the supply networks redesign by considering the expected economic contribution of products and variability of the demand.

Future Parking Demand at Rail Stations in Klang Valley

Directory of Open Access Journals (Sweden)

Ho Phooi Wai

2017-01-01

Full Text Available Klang Valley, Malaysia is currently undergoing a massive development of rail transportation system expansion where the current integrated rail transit system will see new extensions of two MRT lines and an LRT line by year 2020. By year 2017, the first MRT line will be ready to run with 31 new rail stations connected to the current passenger rail network. The existing Park and Ride facilities in Klang Valley are commonly known as being unable to sufficiently cater for the current parking space demand. Therefore, with the expansion of many additional rail stations which are rapidly under construction, there are doubts that the future parking space at rail stations will be able to accommodate the sudden rise of rail passengers. Although the authorities are increasing parking bays at various locations, will the future parking demand at rail stations be sufficient? This paper studies the factors influencing parking demand in terms of population, car ownership, new car registrations and passenger rail ridership and estimating the future parking demand using Linear Regression method. Result shows that the forecasted parking demand at rail stations after the implementation of the first new MRT system in 2017 is 2.7 times more than in 2014.

Supply and Demand for Improved Sanitation: Results from Randomized Pricing Experiments in Rural Tanzania.

Science.gov (United States)

Peletz, Rachel; Cock-Esteb, Alicea; Ysenburg, Dorothea; Haji, Salim; Khush, Ranjiv; Dupas, Pascaline

2017-06-20

Improving access to sanitation is a global public health priority. Sufficient consumer demand is required for sanitation coverage to expand through private provision. To measure consumer demand for hygienic latrine platform products in rural Tanzania, we conducted a randomized, voucher-based real-money sales trial with 1638 households with unimproved latrines. We also evaluated multiple supply chain options to determine the costs of supplying latrine platform products to rural households. For concrete latrine SanPlats, 60% of households were willing to pay US$0.48 and 10% of households were willing to pay US$4.05, yet the average cost of supplying the SanPlat to households was US$7.51. Similarly, for plastic sanitary platforms, willingness-to-pay (WTP) dropped from almost 60% at a price of US$1.43 to 5% at a price of US$12.29, compared to an average supply cost of US$23.28. WTP was not significantly different between villages that had participated in the National Sanitation Campaign and those that had not. Randomized informational interventions, including hygiene data-sharing and peer-based exposure to latrine platform products, had minimal effects on WTP. In conclusion, current household demand for latrine platform products is too low to achieve national goals for improved sanitation coverage through fully commercial distribution.

Study of an intraurban travel demand model incorporating commuter preference variables

Science.gov (United States)

Holligan, P. E.; Coote, M. A.; Rushmer, C. R.; Fanning, M. L.

1971-01-01

The model is based on the substantial travel data base for the nine-county San Francisco Bay Area, provided by the Metropolitan Transportation Commission. The model is of the abstract type, and makes use of commuter attitudes towards modes and simple demographic characteristics of zones in a region to predict interzonal travel by mode for the region. A characterization of the STOL/VTOL mode was extrapolated by means of a subjective comparison of its expected characteristics with those of modes characterized by the survey. Predictions of STOL demand were made for the Bay Area and an aircraft network was developed to serve this demand. When this aircraft system is compared to the base case system, the demand for STOL service has increased five fold and the resulting economics show considerable benefit from the increased scale of operations. In the previous study all systems required subsidy in varying amounts. The new system shows a substantial profit at an average fare of $3.55 per trip.

Modelling Commodity Demands and Labour Supply with m-Demands

OpenAIRE

Browning, Martin

1999-01-01

In the empirical modelling of demands and labour supply we often lack data on a full set of goods. The usual response is to invoke separability assumptions. Here we present an alternative based on modelling demands as a function of prices and the quantity of a reference good rather than total expenditure. We term such demands m-demands. The advantage of this approach is that we make maximum use of the data to hand without invoking implausible separability assumptions. In the theory section qu...

Nurses' work demands and work-family conflict: a questionnaire survey.

Science.gov (United States)

Yildirim, Dilek; Aycan, Zeynep

2008-09-01

Work-family conflict is a type of interrole conflict that occurs as a result of incompatible role pressures from the work and family domains. Work role characteristics that are associated with work demands refer to pressures arising from excessive workload and time pressures. Literature suggests that work demands such as number of hours worked, workload, shift work are positively associated with work-family conflict, which, in turn is related to poor mental health and negative organizational attitudes. The role of social support has been an issue of debate in the literature. This study examined social support both as a moderator and a main effect in the relationship among work demands, work-to-family conflict, and satisfaction with job and life. This study examined the extent to which work demands (i.e., work overload, irregular work schedules, long hours of work, and overtime work) were related to work-to-family conflict as well as life and job satisfaction of nurses in Turkey. The role of supervisory support in the relationship among work demands, work-to-family conflict, and satisfaction with job and life was also investigated. The sample was comprised of 243 participants: 106 academic nurses (43.6%) and 137 clinical nurses (56.4%). All of the respondents were female. The research instrument was a questionnaire comprising nine parts. The variables were measured under four categories: work demands, work support (i.e., supervisory support), work-to-family conflict and its outcomes (i.e., life and job satisfaction). The structural equation modeling results showed that work overload and irregular work schedules were the significant predictors of work-to-family conflict and that work-to-family conflict was associated with lower job and life satisfaction. Moderated multiple regression analyses showed that social support from the supervisor did not moderate the relationships among work demands, work-to-family conflict, and satisfaction with job and life. Exploratory

R&D and Price Elasticity of Demand

DEFF Research Database (Denmark)

Lucke, D.; Schröder, Philipp; D., Schumacher,

2004-01-01

This paper explores the relationship between the price elasticity of demand and the R&D intensity of the product. We introduce the concept of R&D intensity into a standard Dixit-Stiglitz/Krugman-type setting. R&D activity is treated as a fixed cost of production. Within this framework, sectors...... with a higher R&D intensity show a lower price elasticity of demand. This proposition is confirmed by an empirical investigation of export demand for manufactured goods from major industrialised countries. Consequently, real exchange rate changes have an impact on the commodity structure of exports....

Measuring the security of energy exports demand in OPEC economies

International Nuclear Information System (INIS)

Dike, Jude Chukwudi

2013-01-01

One of the objectives of OPEC is the security of demand for the crude oil exports of its members. Achieving this objective is imperative with the projected decline in OECD countries' crude oil demand among other crude oil demand shocks. This paper focuses on determining the external crude oil demand security risks of OPEC member states. In assessing these risks, this study introduces two indexes. The first index, Risky Energy Exports Demand (REED), indicates the level of energy export demand security risks for OPEC members. It combines measures of export dependence, economic dependence, monopsony risk and transportation risk. The second index, Contribution to OPEC Risk Exposure (CORE), indicates the individual contribution of the OPEC members to OPEC's risk exposure. This study utilises the disaggregated index approach in measuring energy demand security risks for crude oil and natural gas and involves a country level analysis. With the disaggregated approach, the study shows that OPEC's energy export demand security risks differ across countries and energy types. - Highlights: • REED and CORE indexes are suitable measures for energy exports demand security risk. • The indexes show that energy demand security risk is different for each OPEC country. • The countries contribution to OPEC's energy demand security risk is also different. • The outcome is necessary for OPEC's common energy and climate change policies. • The outcome makes a case for oil demand security as a topical issue in the literature

Trading the Economic Value of Unsatisfied Municipal Water Demand

Science.gov (United States)

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

Trading the Economic Value of Unsatisfied Municipal Water Demand

Directory of Open Access Journals (Sweden)

D. B. Telfah

2018-06-01

Full Text Available 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

Mapping Urban Heat Demand with the Use of GIS-Based Tools

Directory of Open Access Journals (Sweden)

Artur Wyrwa

2017-05-01

Full Text Available This article presents a bottom-up approach for calculation of the useful heat demand for space heating and hot water preparation using geo-referenced datasets for buildings at the city level. This geographic information system (GIS based approach was applied in the case study for the city of Krakow, where on the one hand the district heat network is well developed, while on the other hand there are still substantial number of buildings burning solid fuels in individual boilers and stoves, causing air pollution. The calculated heat demand was aggregated in the grid with 100 m × 100 m spatial resolution to deliver the heat map depicting the current situation for 21 buildings types. The results show that the residential buildings, in particular one- and multi-family buildings, have the highest share in overall demand for heat. By combining the results with location of the district heat (DH network, the potential areas in its close vicinity that have sufficient heat demand density for developing the net were pointed out. Future evolution in heat demand for space heating in one-family houses was evaluated with the use of deterministic method employing building stock model. The study lays a foundation for planning the development of the heating system at the city level.

Does responsive pricing smooth demand shocks?

OpenAIRE

Pascal, Courty; Mario, Pagliero

2011-01-01

Using data from a unique pricing experiment, we investigate Vickrey’s conjecture that responsive pricing can be used to smooth both predictable and unpredictable demand shocks. Our evidence shows that increasing the responsiveness of price to demand conditions reduces the magnitude of deviations in capacity utilization rates from a pre-determined target level. A 10 percent increase in price variability leads to a decrease in the variability of capacity utilization rates between...

Extreme daily increases in peak electricity demand: Tail-quantile estimation

International Nuclear Information System (INIS)

Sigauke, Caston; Verster, Andréhette; Chikobvu, Delson

2013-01-01

A Generalized Pareto Distribution (GPD) is used to model extreme daily increases in peak electricity demand. The model is fitted to years 2000–2011 recorded data for South Africa to make a comparative analysis with the Generalized Pareto-type (GP-type) distribution. Peak electricity demand is influenced by the tails of probability distributions as well as by means or averages. At times there is a need to depart from the average thinking and exploit information provided by the extremes (tails). Empirical results show that both the GP-type and the GPD are a good fit to the data. One of the main advantages of the GP-type is the estimation of only one parameter. Modelling of extreme daily increases in peak electricity demand helps in quantifying the amount of electricity which can be shifted from the grid to off peak periods. One of the policy implications derived from this study is the need for day-time use of electricity billing system similar to the one used in the cellular telephone/and fixed line-billing technology. This will result in the shifting of electricity demand on the grid to off peak time slots as users try to avoid high peak hour charges. - Highlights: ► Policy makers should design demand response strategies to save electricity. ► Peak electricity demand is influenced by tails of probability distributions. ► Both the GSP and the GPD are a good fit to the data. ► Accurate assessment of level and frequency of extreme load forecasts is important.

Money Demand Features in CEE Countries

Directory of Open Access Journals (Sweden)

Valentina-Ioana MERA

2016-01-01

Full Text Available The existence of a stable relationship between money demand and its determinants is important for the efficiency of monetary policy. In this paper we carried a preliminary analysis on the variables that can influence money demand in five Central and Eastern European countries (Bulgaria, Czech Republic, Hungary, Poland and Romania in order to determine which characteristics define the evolution of money demand and its determinants, and how volatile they are. The results indicate a number of similarities in terms of monetary development and also suggest that some additional variables that may influence money demand in this specific sample.

The role of workaholism in the job demands-resources model.

Science.gov (United States)

Molino, Monica; Bakker, Arnold B; Ghislieri, Chiara

2016-07-01

The present study tries to gain more insight in workaholism by investigating its antecedents and consequences using the job demands-resources model. We hypothesized that job demands would be positively related to workaholism, particularly when job resources are low. In addition, we hypothesized that workaholism would be positively related to negative outcomes in three important life domains: health, family, and work. The research involved 617 Italian workers (employees and self-employed). To test the hypotheses we applied structural equation modeling (SEM) and moderated structural equation modeling (MSEM) using Mplus 6. The results of SEM showed a good model where workload, cognitive demands, emotional demands, and customer-related social stressors were positively related to workaholism and work-family conflict (WFC) (partial mediation). Additionally, workaholism was indirectly related to exhaustion and intentions to change jobs through WFC. Moreover, MSEM analyses confirmed that job resources (job security and opportunities for development) buffered the relationship between job demands and workaholism. Particularly, the interaction effects were statistically significant in five out of eight combinations. These findings suggest that workaholism is a function of a suboptimal work environment and predicts unfavorable employee outcomes. We discuss the theoretical and practical implications of these findings.

Effects of visually demanding near work on trapezius muscle activity.

Science.gov (United States)

Zetterberg, C; Forsman, M; Richter, H O

2013-10-01

Poor visual ergonomics is associated with visual and neck/shoulder discomfort, but the relation between visual demands and neck/shoulder muscle activity is unclear. The aims of this study were to investigate whether trapezius muscle activity was affected by: (i) eye-lens accommodation; (ii) incongruence between accommodation and convergence; and (iii) presence of neck/shoulder discomfort. Sixty-six participants (33 controls and 33 with neck pain) performed visually demanding near work under four different trial-lens conditions. Results showed that eye-lens accommodation per se did not affect trapezius muscle activity significantly. However, when incongruence between accommodation and convergence was present, a significant positive relationship between eye-lens accommodation and trapezius muscle activity was found. There were no significant group-differences. It was concluded that incongruence between accommodation and convergence is an important factor in the relation between visually demanding near work and trapezius muscle activity. The relatively low demands on accommodation and convergence in the present study imply that visually demanding near work may contribute to increased muscle activity, and over time to the development of near work related neck/shoulder discomfort. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

Air pollution impacts from demand-side management

International Nuclear Information System (INIS)

Hall, D.C.; Sandii Win, M.; Hall, J.V.

1995-01-01

Air-polluting emission rates and energy-efficiency ratings vary widely among power plants, depending on location, age and whether the power plant is repowered. Traditional regulations require installation of specified emission control equipment that varies among power plants. These regulations do not specify that utilities first dispatch the cleanest power plants as demand varies from peak to off-peak periods. This empirical analysis shows, for 2 years out of 20, that demand-side management (DSM) programs increase air pollution. One reason for this result is that regulations require installation of specific emission-control technology but do not provide the incentive to take actual emissions or their air quality impacts into account when operating the system. For certain types of air pollutants and in some regions, regulatory programs now include markets for tradable emission credits. Such programs may alter this incentive. (author)

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

Science.gov (United States)

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

2010-04-01

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

Maximum spectral demands in the near-fault region

Science.gov (United States)

Huang, Yin-Nan; Whittaker, Andrew S.; Luco, Nicolas

2008-01-01

The Next Generation Attenuation (NGA) relationships for shallow crustal earthquakes in the western United States predict a rotated geometric mean of horizontal spectral demand, termed GMRotI50, and not maximum spectral demand. Differences between strike-normal, strike-parallel, geometric-mean, and maximum spectral demands in the near-fault region are investigated using 147 pairs of records selected from the NGA strong motion database. The selected records are for earthquakes with moment magnitude greater than 6.5 and for closest site-to-fault distance less than 15 km. Ratios of maximum spectral demand to NGA-predicted GMRotI50 for each pair of ground motions are presented. The ratio shows a clear dependence on period and the Somerville directivity parameters. Maximum demands can substantially exceed NGA-predicted GMRotI50 demands in the near-fault region, which has significant implications for seismic design, seismic performance assessment, and the next-generation seismic design maps. Strike-normal spectral demands are a significantly unconservative surrogate for maximum spectral demands for closest distance greater than 3 to 5 km. Scale factors that transform NGA-predicted GMRotI50 to a maximum spectral demand in the near-fault region are proposed.

Energy demand analysis of Port-Harcourt refinery, Nigeria and its policy implications

International Nuclear Information System (INIS)

Jesuleye, O.A.; Siyanbola, W.O.; Sanni, S.A.; Ilori, M.O.

2007-01-01

This paper analyses energy demand of Port-Harcourt refinery, Nigeria, based on information obtained from its annual publications, backed-up by spot interviews. The analytical approach adopted for the study involves the calculation of energy intensities to determine the refinery's annual energy demand for various energy types considered from 1989 to 2004. The results showed that the actual energy demand per year for processing crude oil into refined products, exceeded, in varying degrees the stipulated refinery standard of 4 barrels of oil equivalent (BOE) per 100 BOE. It varied from 4.28-8.58 BOE per 100 BOE. In terms of energy demand efficiency, this implies very poor performance of the refinery during the 16-year period under investigation. The excess demand which translates to an average daily wastage of about 2005 BOE is estimated to be $56,196 (US Dollars) based on the 2003 OPEC basket price of $28.0213 per barrel. Lack of optimal fuel utilization-mix and non-compliance with the Turn-Around-Maintenance schedules were attributed to the refinery's inefficient energy demand pattern

Study of forecasting maximum demand of electric power

Energy Technology Data Exchange (ETDEWEB)

Yoo, B.C.; Hwang, Y.J. [Korea Energy Economics Institute, Euiwang (Korea, Republic of)

1997-08-01

As far as the past performances of power supply and demand in Korea is concerned, one of the striking phenomena is that there have been repeated periodic surpluses and shortages of power generation facilities. Precise assumption and prediction of power demands is the basic work in establishing a supply plan and carrying out the right policy since facilities investment of the power generation industry requires a tremendous amount of capital and a long construction period. The purpose of this study is to study a model for the inference and prediction of a more precise maximum demand under these backgrounds. The non-parametric model considered in this study, paying attention to meteorological factors such as temperature and humidity, does not have a simple proportionate relationship with the maximum power demand, but affects it through mutual complicated nonlinear interaction. I used the non-parametric inference technique by introducing meteorological effects without importing any literal assumption on the interaction of temperature and humidity preliminarily. According to the analysis result, it is found that the non-parametric model that introduces the number of tropical nights which shows the continuity of the meteorological effect has better prediction power than the linear model. The non- parametric model that considers both the number of tropical nights and the number of cooling days at the same time is a model for predicting maximum demand. 7 refs., 6 figs., 9 tabs.

Gasoline demand in Europe. New insights

International Nuclear Information System (INIS)

Pock, Markus

2010-01-01

This study utilizes a panel data set from 14 European countries over the period 1990-2004 to estimate a dynamic model specification for gasoline demand. Previous studies estimating gasoline consumption per total passenger cars ignore the recent increase in the number of diesel cars in most European countries leading to biased elasticity estimates. We apply several common dynamic panel estimators to our small sample. Results show that specifications neglecting the share of diesel cars overestimate short-run income, price and car ownership elasticities. It appears that the results of standard pooled estimators are more reliable than common IV/GMM estimators applied to our small data set. (author)

Gasoline demand in Europe. New insights

Energy Technology Data Exchange (ETDEWEB)

Pock, Markus [Department of Economics and Finance, HealthEcon IHS - Institute for Advanced Studies, Vienna Stumpergasse 56, 1060 Vienna (Austria)

2010-01-15

This study utilizes a panel data set from 14 European countries over the period 1990-2004 to estimate a dynamic model specification for gasoline demand. Previous studies estimating gasoline consumption per total passenger cars ignore the recent increase in the number of diesel cars in most European countries leading to biased elasticity estimates. We apply several common dynamic panel estimators to our small sample. Results show that specifications neglecting the share of diesel cars overestimate short-run income, price and car ownership elasticities. It appears that the results of standard pooled estimators are more reliable than common IV/GMM estimators applied to our small data set. (author)

The relationship among customer demand, competitive strategy and manufacturing system functional objectives

Directory of Open Access Journals (Sweden)

Wei Xu

2013-09-01

Full Text Available Purpose: To ascertain the relationship between the operation system function goal decision making and customer demand and competition strategy, can better discover and integrate all available resources (including important capital resources to achieve business opportunities, the establishment of sustainable competitive ability. Because, to achieve business development lead policymakers take great uncertainty, which led to the investment behavior required for the operational activities of resources also bear the enormous risks. Design/methodology/approach: Through principal component analysis on the data collected by questionnaires, the manuscript obtains dominant factors for customer demand, competitive strategy and manufacturing system functional objectives respectively. By these factors, it tests its three hypotheses with the data from northeast of China and draws some conclusions. Findings: The results show that customer demand have a significant positive effect on competitive strategy; competitive strategy have positive influence on manufacturing system functional objectives; customer demand affect the functional objectives, by competitive strategy. Research limitations/implications: In this research, competitive strategy and manufacturing system functional objectives are influenced by customer demand. The conclusion of the research can provide theoretical guidance for Chinese enterprises which carry out manufacturing system functional objectives. Originality/value: In this research, a new measure questionnaire of competition strategy, customer satisfaction and operating system function goal was used, analyzed the influence factors of time, quality, cost, efficiency, service and environment, on the operation of the system. The study shows that the effect of competition strategy and customer demand has a direct impact on the operating system functions, customer demand through competitive strategy of indirect effects operating system functions.

Gun Shows and Gun Violence: Fatally Flawed Study Yields Misleading Results

Science.gov (United States)

Hemenway, David; Webster, Daniel; Pierce, Glenn; Braga, Anthony A.

2010-01-01

A widely publicized but unpublished study of the relationship between gun shows and gun violence is being cited in debates about the regulation of gun shows and gun commerce. We believe the study is fatally flawed. A working paper entitled “The Effect of Gun Shows on Gun-Related Deaths: Evidence from California and Texas” outlined this study, which found no association between gun shows and gun-related deaths. We believe the study reflects a limited understanding of gun shows and gun markets and is not statistically powered to detect even an implausibly large effect of gun shows on gun violence. In addition, the research contains serious ascertainment and classification errors, produces results that are sensitive to minor specification changes in key variables and in some cases have no face validity, and is contradicted by 1 of its own authors’ prior research. The study should not be used as evidence in formulating gun policy. PMID:20724672

The Dynamic Response Process to Conflicting Institutional Demands in MNC Subsidiaries

DEFF Research Database (Denmark)

Holm, Alison E.; Decreton, Benoit; Nell, Phillip Christopher

2017-01-01

How do subsidiary managers react when their headquarters managers make requests that conflict with the local environment in which the subsidiary operates? Using data from a subsidiary based in Sub-Saharan Africa and headquartered in Europe, we show that subsidiary managers need more time than...... usually expected to react to headquarters demands. Subsidiary managers sometimes postpone or test headquarters demands before deciding how to respond to them. In addition, subsidiary managers can implement headquarters demands in ways that do not fit the expectations from the headquarters or local actors...... (e.g. customers, suppliers), thus resulting in additional delays. Headquarters managers must be aware that implementation can take longer than they anticipate, particularly for subsidiaries located in environments that differ substantially from the environment of the headquarters....

Too easy? The influence of task demands conveyed tacitly on prospective memory

Science.gov (United States)

Lourenço, Joana S.; Hill, Johnathan H.; Maylor, Elizabeth A.

2015-01-01

Previous research suggests that when intentions are encoded, participants establish an attention allocation policy based on their metacognitive beliefs about how demanding it will be to fulfill the prospective memory (PM) task. We investigated whether tacit PM demands can influence judgments about the cognitive effort required for success, and, as a result, affect ongoing task interference and PM performance. Participants performed a lexical decision task in which a PM task of responding to animal words was embedded. PM demands were tacitly manipulated by presenting participants with either typical or atypical animal exemplars at both instructions and practice (low vs. high tacit demands, respectively). Crucially, objective PM task demands were the same for all participants as PM targets were always atypical animals. Tacit demands affected participants’ attention allocation policies such that task interference was greater for the high than low demands condition. Also, PM performance was reduced in the low relative to the high demands condition. Participants in the low demands condition who succeeded to the first target showed a subsequent increase in task interference, suggesting adjustment to the higher than expected demands. This study demonstrates that tacit information regarding the PM task can affect ongoing task processing as well as harm PM performance when actual demands are higher than expected. Furthermore, in line with the proposal that attention allocation is a dynamic and flexible process, we found evidence that PM task experience can trigger changes in ongoing task interference. PMID:25983687

The composition of demand for newly launched vaccines: results from the pneumococcal and rotavirus vaccine introductions in Ethiopia and Malawi.

Science.gov (United States)

Williams, B Adam; Kidane, Teklay; Chirwa, Geoffrey; Tesfaye, Neghist; Prescott, Marta R; Scotney, Soleine T; Valle, Moussa; Abebe, Sintayehu; Tambuli, Adija; Malewezi, Bridget; Mohammed, Tahir; Kobayashi, Emily; Wootton, Emily; Wong, Renee; Dosani, Rahima; Subramaniam, Hamsa; Joseph, Jessica; Yavuz, Elif; Apple, Aliza; Le Tallec, Yann; Kang'ethe, Alice

2016-06-01

Understanding post-launch demand for new vaccines can help countries maximize the benefits of immunization programmes. In particular, low- and middle-income countries (LMICs) should ensure adequate resource planning with regards to stock consumption and service delivery for new vaccines, whereas global suppliers must produce enough vaccines to meet demand. If a country underestimates the number of children seeking vaccination, a stock-out of commodities will create missed opportunities for saving lives. We describe the post-launch demand for the first dose of pneumococcal conjugate vaccine (PCV1) in Ethiopia and Malawi and the first dose of rotavirus vaccine (Rota1) in Malawi, with focus on the new birth cohort and the 'backlog cohort', comprised of older children who are still eligible for vaccination at the time of launch. PCV1 and Rota1 uptake were compared with the demand for the first dose of pentavalent vaccine (Penta1), a routine immunization that targets the same age group and immunization schedule. In the first year, the total demand for PCV1 was 37% greater than that of Penta1 in Ethiopia and 59% greater in Malawi. In the first 6 months, the demand of Rota1 was only 5.9% greater than Penta1 demand in Malawi. Over the first three post-introduction months, 70.7% of PCV1 demand in Ethiopia and 71.5% of demand in Malawi came from children in the backlog cohort, whereas only 28.0% of Rota1 demand in Malawi was from the backlog cohort. The composition of demand was impacted by time elapsed since vaccine introduction and age restrictions. Evidence suggests that countries' plans should account for the impact of backlog demand, especially in the first 3 months post-introduction. LMICs should request for higher stock volumes when compared with routine needs, plan social mobilization activities to reach the backlog cohort and allocate human resources and cold chain capacity to accommodate high demand following vaccine introduction. © The Author 2016. Published by

Uranium resources, demand and production

International Nuclear Information System (INIS)

Stipanicic, P.N.

1985-05-01

Estimations of the demand and production of principal uranium resource categories are presented. The estimations based on data analysis made by a joint 'NEA/IAEA Working Party on Uranium Resources' and the corresponding results are published by the OECD (Organization for Economic Co-operation and Development) in the 'Uranium Resources, Production and Demand' Known as 'Red Book'. (M.C.K.) [pt

The global food crisis : supply and demand revisited

OpenAIRE

Sammut, Vince

2015-01-01

This study aims to show that the volatility in food prices between 2008 and 2011 cannot be explained merely by the market fundamentals of demand and supply. While global changes in demand and supply are bringing about radical changes to the food equation, evidence shows that market failure in the world grain market aggravated the problem. Excess liquidity, brought about by monetary growth policies after the subprime crises and financial meltdown in 2008, has stimulated speculation and hoar...

Optimal transport on supply-demand networks.

Science.gov (United States)

Chen, Yu-Han; Wang, Bing-Hong; Zhao, Li-Chao; Zhou, Changsong; Zhou, Tao

2010-06-01

In the literature, transport networks are usually treated as homogeneous networks, that is, every node has the same function, simultaneously providing and requiring resources. However, some real networks, such as power grids and supply chain networks, show a far different scenario in which nodes are classified into two categories: supply nodes provide some kinds of services, while demand nodes require them. In this paper, we propose a general transport model for these supply-demand networks, associated with a criterion to quantify their transport capacities. In a supply-demand network with heterogeneous degree distribution, its transport capacity strongly depends on the locations of supply nodes. We therefore design a simulated annealing algorithm to find the near optimal configuration of supply nodes, which remarkably enhances the transport capacity compared with a random configuration and outperforms the degree target algorithm, the betweenness target algorithm, and the greedy method. This work provides a start point for systematically analyzing and optimizing transport dynamics on supply-demand networks.

The demand for consumer health information.

Science.gov (United States)

Wagner, T H; Hu, T W; Hibbard, J H

2001-11-01

Using data from an evaluation of a community-wide informational intervention, we modeled the demand for medical reference books, telephone advice nurses, and computers for health information. Data were gathered from random household surveys in Boise, ID (experimental site), Billings, MT, and Eugene, OR (control sites). Conditional difference-in-differences show that the intervention increased the use of medical reference books, advice nurses, and computers for health information by approximately 15, 6, and 4%. respectively. The results also suggest that the intervention was associated with a decreased reliance on health professionals for information.

Econophysics of a ranked demand and supply resource allocation problem

Science.gov (United States)

Priel, Avner; Tamir, Boaz

2018-01-01

We present a two sided resource allocation problem, between demands and supplies, where both parties are ranked. For example, in Big Data problems where a set of different computational tasks is divided between a set of computers each with its own resources, or between employees and employers where both parties are ranked, the employees by their fitness and the employers by their package benefits. The allocation process can be viewed as a repeated game where in each iteration the strategy is decided by a meta-rule, based on the ranks of both parties and the results of the previous games. We show the existence of a phase transition between an absorbing state, where all demands are satisfied, and an active one where part of the demands are always left unsatisfied. The phase transition is governed by the ratio between supplies and demand. In a job allocation problem we find positive correlation between the rank of the workers and the rank of the factories; higher rank workers are usually allocated to higher ranked factories. These all suggest global emergent properties stemming from local variables. To demonstrate the global versus local relations, we introduce a local inertial force that increases the rank of employees in proportion to their persistence time in the same factory. We show that such a local force induces non trivial global effects, mostly to benefit the lower ranked employees.

Coal demand prediction based on a support vector machine model

Energy Technology Data Exchange (ETDEWEB)

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

2007-01-15

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

The Impact of Task Demands on Fixation-Related Brain Potentials during Guided Search.

Directory of Open Access Journals (Sweden)

Anthony J Ries

Full Text Available Recording synchronous data from EEG and eye-tracking provides a unique methodological approach for measuring the sensory and cognitive processes of overt visual search. Using this approach we obtained fixation related potentials (FRPs during a guided visual search task specifically focusing on the lambda and P3 components. An outstanding question is whether the lambda and P3 FRP components are influenced by concurrent task demands. We addressed this question by obtaining simultaneous eye-movement and electroencephalographic (EEG measures during a guided visual search task while parametrically modulating working memory load using an auditory N-back task. Participants performed the guided search task alone, while ignoring binaurally presented digits, or while using the auditory information in a 0, 1, or 2-back task. The results showed increased reaction time and decreased accuracy in both the visual search and N-back tasks as a function of auditory load. Moreover, high auditory task demands increased the P3 but not the lambda latency while the amplitude of both lambda and P3 was reduced during high auditory task demands. The results show that both early and late stages of visual processing indexed by FRPs are significantly affected by concurrent task demands imposed by auditory working memory.

Single-Family Houses That Meet The Future Energy Demands

DEFF Research Database (Denmark)

Rose, Jørgen; Svendsen, Svend

2002-01-01

). Before any further tightening of the regulations are introduced, however, it is necessary to illustrate the consequences of such actions with regard to finance, building technology, indoor climate and comfort. Therefore a series of investigations and experimental projects are being launched, in order...... to examine these consequences thoroughly. The department is presently contributing to this end by participating in quite a few investigative projects, where single-family houses are designed to meet the proposed future energy demands. This paper describes the results obtained from one such project where...... the department, in co-operation with a major building entrepreneur, has developed a single-family house that shows that there are no evident problems in meeting the future energy demands....

ECONOMETRIC ANALYSIS OF CEREAL DEMAND IN MOROCCO USING THE ALMOST IDEAL DEMAND SYSTEM

Directory of Open Access Journals (Sweden)

Sara Essaten

2018-04-01

Full Text Available Following up the agricultural policy in Morocco and enforcing it, the new strategy Green Morocco Plan (GMP launched in 2008 also stressed on the cereals’ supply. Meantime, despite their significant nutritional role, little attention has been paid to the demand side. This paper intends to perform an econometric analysis of the demand of five main cereals - Common wheat, Durum wheat, Barley, Corn and Rice- using a linear version of the flexible Almost Ideal Demand System (LA/AIDS model. A Seemingly Unrelated Regression (SUR approach has been applied to the demand system equations with annual data covering the period from 1980 to 2015. At the overall, regular econometric restrictions (stability, structural separability, validity, etc. have been respected our results suggest that the relations of complementarity or substitution are not determining in the cereal bundle in Morocco. Also, the Moroccan consumer behavior is characterized by a strong sensibility towards common wheat price’s changes and by a difficult access for the durum wheat as it is considered as luxury good.

The Sensitivity of Residential Electricity Demand in Indonesia

Directory of Open Access Journals (Sweden)

Stranti Nastiti Kusumaningrum

2018-03-01

Full Text Available Since 2013, the residential electricity price for High VA (Volt-Ampere households has changed due to changes in pricing policies. This paper analyzes the responsiveness of residential electricity demand to the change in electricity prices and income among two different household groups (Low VA and High VA in 2011 and 2014. Using an electricity consumption model and the Quantile Regression method, the results show that residential electricity demand is price and income inelastic. Income elasticity is lower than price elasticity. Furthermore, the effects on price elasticity also found in the Low VA group, whose rate remained stable. At the same time, evidence proves the impact of the change in pricing policy on income elasticity remains unclear. This result implies that the government has to be more careful in regulating electricity prices for the low VA group, while maintaining economic stability.DOI: 10.15408/sjie.v7i2.6048

Temperature effects on future energy demand in Sub-Saharan Africa

Science.gov (United States)

Shivakumar, Abhishek

2016-04-01

Climate change is projected to adversely impact different parts of the world to varying extents. Preliminary studies show that Sub-Saharan Africa is particularly vulnerable to climate change impacts, including changes to precipitation levels and temperatures. This work will analyse the effect of changes in temperature on critical systems such as energy supply and demand. Factors that determine energy demand include income, population, temperature (represented by cooling and heating degree days), and household structures. With many countries in Sub-Saharan Africa projected to experience rapid growth in both income and population levels, this study aims to quantify the amplified effects of these factors - coupled with temperature changes - on energy demand. The temperature effects will be studied across a range of scenarios for each of the factors mentioned above, and identify which of the factors is likely to have the most significant impact on energy demand in Sub-Saharan Africa. Results of this study can help set priorities for decision-makers to enhance the climate resilience of critical infrastructure in Sub-Saharan Africa.

Why Should We Demand Equality of Educational Opportunity?

Science.gov (United States)

Meyer, Kirsten

2016-01-01

This paper reveals how equal educational opportunities, equal job opportunities and equality of opportunity for welfare are related to each other, and how they are related to other demands for justice. There are several important objections to the emphasis on equal educational opportunities. Nevertheless, this paper shows that demanding equal…

Norwegian Residential Energy Demand: Coordinated use of a System Engineering and a Macroeconomic Model

Directory of Open Access Journals (Sweden)

Tor A Johnsen

1996-07-01

Full Text Available In Norway, the system engineering model MARKAL and the macroeconomic model MSG-EE are both used in studies of national CO2 controlling strategies. MARKAL is a linear programming model that calculates a composite set of technologies necessary to meet demand and environmental constraints at minimised total energy expenditure. MSG-EE is an applied general equilibrium model including the link between economic activity, energy demand and emissions to air. MSG-EE has a theory consistent description of the link between income, prices and energy demand, but the representation of technological improvements is simple. MARKAL has a sophisticated description of future energy technology options, but includes no feedback to the general economy. A project for studying the potential for a coordinated use of these two models was initiated and funded by the Norwegian Research Council (NFR. This paper gives a brief presentation of the two models. Results from independent model calculations show that MARKAL gives a signficant lower residential energy demand than MSG-EE does. This is explained by major differences in modelling approach. A first attempt of coordinating the residential energy demand in the models is reported. This attempt shows that implementing results from MARKAL, in MSG-EE for the residential sector alone gives little impact on the general economy. A further development of an iteration procedure between the models should include all energy using sectors.

Evaluating demand side measures in simulation models for the power market

International Nuclear Information System (INIS)

Wolfgang, Ove; Doorman, Gerard

2011-01-01

Increased energy efficiency is one of the pillars for reducing CO 2 emissions. However, in models for the electricity market like unit commitment and dispatch models, increased efficiency of demand results in a paradoxical apparent reduction of the total economic surplus. The reason is that these are partial models for the electricity market, which do not take into account the effect of the changes in other markets. This paper shows how the calculation of the consumer surplus in the electricity market should be corrected to take into account the effect in other markets. In different cases we study shifts in the demand curve that are caused by increased energy efficiency, reduced cost for substitutes to electricity and real-time monitoring of demand, and we derive the necessary correction. The correction can easily be included in existing simulation models, and makes it possible to assess the effect of changes in demand on economic surplus. (author)

Electric Water Heater Modeling and Control Strategies for Demand Response

Energy Technology Data Exchange (ETDEWEB)

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

2012-07-22

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

Electricity demand by the commercial sector in Kuwait: an econometric analysis

International Nuclear Information System (INIS)

Eltony, M.N.; Hajeeh, M.

1999-01-01

This paper models and estimates electricity demand by the Kuwaiti commercial sector, using an error correction model. It also simulates the estimated model under three scenarios and presents an analysis of the results. The empirical results indicate that short- and long-run electricity consumption and the level of economic activity are interrelated. The forecasts show that electricity consumption varies directly with economic growth. They also suggest that an increase of 100 per cent in nominal electricity prices will lead to a reduction in commercial sector electricity demand of 45 per cent by the year 2010. The simulation of the model under the different scenarios demonstrates that the potential for energy conservation exists in the commercial sector

Innovation and Demand

DEFF Research Database (Denmark)

Andersen, Esben Sloth

2007-01-01

the demand-side of markets in the simplest possible way. This strategy has allowed a gradual increase in the sophistication of supply-side aspects of economic evolution, but the one-sided focus on supply is facing diminishing returns. Therefore, demand-side aspects of economic evolution have in recent years...... received increased attention. The present paper argues that the new emphasis on demand-side factors is quite crucial for a deepened understanding of economic evolution. The major reasons are the following: First, demand represents the core force of selection that gives direction to the evolutionary process....... Second, firms' innovative activities relate, directly or indirectly, to the structure of expected and actual demand. Third, the demand side represents the most obvious way of turning to the much-needed analysis of macro-evolutionary change of the economic system....

Australia's long-term electricity demand forecasting using deep neural networks

OpenAIRE

Hamedmoghadam, Homayoun; Joorabloo, Nima; Jalili, Mahdi

2018-01-01

Accurate prediction of long-term electricity demand has a significant role in demand side management and electricity network planning and operation. Demand over-estimation results in over-investment in network assets, driving up the electricity prices, while demand under-estimation may lead to under-investment resulting in unreliable and insecure electricity. In this manuscript, we apply deep neural networks to predict Australia's long-term electricity demand. A stacked autoencoder is used in...

India Edible Oil Consumption: A Censored Incomplete Demand Approach

OpenAIRE

Pan, Suwen; Mohanty, Samarendu; Welch, Mark

2008-01-01

A Censored Incomplete Demand System is applied to household expenditures for edible oil in India. The results show that edible peanut oil is still a luxury good in India, whereas expenditure elasticities for other edible oils are relatively low. The food habit, location, education of household heads, and other demographic variables have significant effects on the choice of edible oils.

Effective production planning for purchased part under long lead time and uncertain demand: MRP Vs demand-driven MRP

Science.gov (United States)

Shofa, M. J.; Moeis, A. O.; Restiana, N.

2018-04-01

MRP as a production planning system is appropriate for the deterministic environment. Unfortunately, most production systems such as customer demands are stochastic, so that MRP is inappropriate at the time. Demand-Driven MRP (DDMRP) is new approach for production planning system dealing with demand uncertainty. The objective of this paper is to compare the MRP and DDMRP for purchased part under long lead time and uncertain demand in terms of average inventory levels. The evaluation is conducted through a discrete event simulation with the long lead time and uncertain demand scenarios. The next step is evaluating the performance of DDMRP by comparing the inventory level of DDMRP with MRP. As result, DDMRP is more effective production planning than MRP in terms of average inventory levels.

Demand Modelling in Telecommunications

Directory of Open Access Journals (Sweden)

M. Chvalina

2009-01-01

Full Text Available This article analyses the existing possibilities for using Standard Statistical Methods and Artificial Intelligence Methods for a short-term forecast and simulation of demand in the field of telecommunications. The most widespread methods are based on Time Series Analysis. Nowadays, approaches based on Artificial Intelligence Methods, including Neural Networks, are booming. Separate approaches will be used in the study of Demand Modelling in Telecommunications, and the results of these models will be compared with actual guaranteed values. Then we will examine the quality of Neural Network models. 

Water stress as a trigger of demand change: exploring the implications for drought planning

Science.gov (United States)

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.

time-series analysis of nigeria rice supply and demand: error ...

African Journals Online (AJOL)

O. Ojogho Ph.D

the two series have been changing which may continue for longer time than foreseen {Figure (1c)}. Figure (c) shows a forecast of rice supply and demand for Nigeria. It shows that beyond 2010, rice supply will permanently lead rice demand. This indicates that they either have time-varying means, time-varying variances or ...

HOUSEHOLD FOOD DEMAND IN INDONESIA: A TWO-STAGE BUDGETING APPROACH

Directory of Open Access Journals (Sweden)

Agus Widarjono

2016-05-01

Full Text Available A two-stage budgeting approach was applied to analyze the food demand in urban areas separated by geographical areas and classified by income groups. The demographically augmented Quadratic Almost Ideal Demand System (QUAIDS was employed to estimate the demand elasticity. Data from the National Social and Economic Survey of Households (SUSENAS in 2011 were used. The demand system is a censored model because the data contains zero expenditures and is estimated by employing the consistent two-step estimation procedure to solve biased estimation. The results show that price and income elasticities become less elastic from poor households to rich households. Demand by urban households in Java is more responsive to price but less responsive to income than urban households outside of Java. Simulation policies indicate that an increase in food prices would have more adverse impacts than a decrease in income levels. Poor families would suffer more than rich families from rising food prices and/or decreasing incomes. More importantly, urban households on Java are more vulnerable to an economic crisis, and would respond by reducing their food consumption. Economic policies to stabilize food prices are better than income policies, such as the cash transfer, to maintain the well-being of the population in Indonesia

Energy demand patterns

Energy Technology Data Exchange (ETDEWEB)

Hoffmann, L; Schipper, L; Meyers, S; Sathaye, J; Hara, Y

1984-05-01

This report brings together three papers on energy demand presented at the Energy Research Priorities Seminar held in Ottawa on 8-10 August 1983. The first paper suggests a framework in which energy demand studies may be organized if they are to be useful in policy-making. Disaggregation and the analysis of the chain of energy transformations are possible paths toward more stable and reliable parameters. The second paper points to another factor that leads to instability in sectoral parameters, namely a changeover from one technology to another; insofar as technologies producing a product (or service) vary in their energy intensity, a technological shift will also change the energy intensity of the product. Rapid technological change is characteristic of some sectors in developing countries, and may well account for the high aggregate GDP-elasticities of energy consumption observed. The third paper begins with estimates of these elasticities, which were greater than one for all the member countries of the Asian Development Bank in 1961-78. The high elasticities, together with extreme oil dependence, made them vulnerable to the drastic rise in the oil price after 1973. The author distinguishes three diverging patterns of national experience. The oil-surplus countries naturally gained from the rise in the oil price. Among oil-deficit countries, the newly industrialized countries expanded their exports so rapidly that the oil crisis no longer worried them. For the rest, balance of payments adjustments became a prime concern of policy. Whether they dealt with the oil bill by borrowing, by import substitution, or by demand restraint, the impact of energy on their growth was unmistakable. The paper also shows why energy-demand studies, and energy studies in general, deserve to be taken seriously. 16 refs., 4 figs., 18 tabs.

The future prospects of supply and demand for urologists in Korea

Science.gov (United States)

2017-01-01

Purpose The purpose of this study was to forecast the future supply and demand for urologists and to discuss the possible policy implications. Materials and Methods A demographic utilization-based model was used to calculate the total urologist requirements for Korea. Utilization rates for ambulatory and inpatient genitourinary specialty services were estimated according to age, sex, and insurance status. These rates were used to estimate genitourinary specialty-specific total service utilization expressed in patient care minutes for future populations and converted to genitourinary physician requirements by applying per-genitourinary-physician productivity estimates. An in-and-out movement model for urologist supply was used. Results Depending on assumptions about data at each step in the method, the supply of urologic surgeons is expected to exceed the demand by 2025 under the current enrollment rate of specialists (43.5% in 2012) when comparing the results of the projections under demand scenarios 3 and 4. However, if the current enrollment rate persists, the imbalance in supply and demand will be not severe by 2030. The degree of imbalance can be alleviated by 2030 by maintaining the current occupancy rate of urologic residents of 43.5%. Conclusions This study shows that the number of residents needs to be reduced according to the supply and demand for urologic surgeons. Moreover, a policy should be established to maintain the current occupancy rate of residents. The factors affecting the supply and demand of urologic surgeons are complicated. Thus, comprehensive policies encompassing these factors should be established with appropriate solutions. PMID:29124238

A novel microgrid demand-side management system for manufacturing facilities

Science.gov (United States)

Harper, Terance J.

Thirty-one percent of annual energy consumption in the United States occurs within the industrial sector, where manufacturing processes account for the largest amount of energy consumption and carbon emissions. For this reason, energy efficiency in manufacturing facilities is increasingly important for reducing operating costs and improving profits. Using microgrids to generate local sustainable power should reduce energy consumption from the main utility grid along with energy costs and carbon emissions. Also, microgrids have the potential to serve as reliable energy generators in international locations where the utility grid is often unstable. For this research, a manufacturing process that had approximately 20 kW of peak demand was matched with a solar photovoltaic array that had a peak output of approximately 3 KW. An innovative Demand-Side Management (DSM) strategy was developed to manage the process loads as part of this smart microgrid system. The DSM algorithm managed the intermittent nature of the microgrid and the instantaneous demand of the manufacturing process. The control algorithm required three input signals; one from the microgrid indicating the availability of renewable energy, another from the manufacturing process indicating energy use as a percent of peak production, and historical data for renewable sources and facility demand. Based on these inputs the algorithm had three modes of operation: normal (business as usual), curtailment (shutting off non-critical loads), and energy storage. The results show that a real-time management of a manufacturing process with a microgrid will reduce electrical consumption and peak demand. The renewable energy system for this research was rated to provide up to 13% of the total manufacturing capacity. With actively managing the process loads with the DSM program alone, electrical consumption from the utility grid was reduced by 17% on average. An additional 24% reduction was accomplished when the microgrid

Demand for natural gas: residential and commercial markets in Ontario and British Columbia. [Econometric-model analysis

Energy Technology Data Exchange (ETDEWEB)

Berndt, E R [Univ. of British Columbia, Vancouver; Watkins, G C

1977-02-01

An econometric model is used to project natural gas demand in the residential and commercial market sectors. The model specification is a generalization of one developed by Balestra and Nerlove (Econometrica, 34: 585-612(1966)). Demand that is potentially variable because it is not committed to past investments (flexibe demand) is distinguished from demand that is inflexible because it is tied to existing equipment stocks (captive demand). Attention is focused on the effect of temperature variations on gas demand. The nonlinear equation system is estimated by a maximum-likelihood method, using annual data for British Columbia and Ontario during the period of 1959 to 1974. Results show that only in the long run does price have a significant impact on demand. The model is applicable for medium-term policy simulation, but is limited to natural gas fuel. 15 references.

Psychopathology and tobacco demand.

Science.gov (United States)

Farris, Samantha G; Aston, Elizabeth R; Zvolensky, Michael J; Abrantes, Ana M; Metrik, Jane

2017-08-01

Behavioral economic measurement of the relative value of tobacco (Cigarette Purchase Task; CPT) is used to examine individual differences in motivation for tobacco under certain contexts. Smokers with psychopathology, relative to those without, may demonstrate stronger demand for tobacco following a period of smoking deprivation, which could account for disparate rates of smoking and cessation among this subgroup. Participants (n=111) were community-recruited adult daily smokers who completed the CPT after a deprivation period of approximately 60min. Presence of psychopathology was assessed via clinical interview; 40.5% (n=45) of the sample met criteria for past-year psychological diagnosis. Specifically, 31.5% (n=35) had an emotional disorder (anxiety/depressive disorder), 17.1% (n=19) had a substance use disorder, and 19.1% of the sample had more than one disorder. Smokers with any psychopathology showed significantly higher intensity (demand at unrestricted cost; $0) and O max (peak expenditure for a drug) relative to smokers with no psychopathology. Intensity was significantly higher among smokers with an emotional disorder compared to those without. Smokers with a substance use disorder showed significantly higher intensity and O max , and lower elasticity, reflecting greater insensitivity to price increases. Having≥2 disorders was associated with higher intensity relative to having 1 or no disorders. Findings suggest that presence of psychopathology may be associated with greater and more persistent motivation to smoke. Future work is needed to explore the mechanism linking psychopathology to tobacco demand. Copyright © 2017 Elsevier B.V. All rights reserved.

Supply-demand balance in outward-directed networks and Kleiber's law

Directory of Open Access Journals (Sweden)

Painter Page R

2005-11-01

Full Text Available Abstract Background Recent theories have attempted to derive the value of the exponent α in the allometric formula for scaling of basal metabolic rate from the properties of distribution network models for arteries and capillaries. It has recently been stated that a basic theorem relating the sum of nutrient currents to the specific nutrient uptake rate, together with a relationship claimed to be required in order to match nutrient supply to nutrient demand in 3-dimensional outward-directed networks, leads to Kleiber's law (b = 3/4. Methods The validity of the supply-demand matching principle and the assumptions required to prove the basic theorem are assessed. The supply-demand principle is evaluated by examining the supply term and the demand term in outward-directed lattice models of nutrient and water distribution systems and by applying the principle to fractal-like models of mammalian arterial systems. Results Application of the supply-demand principle to bifurcating fractal-like networks that are outward-directed does not predict 3/4-power scaling, and evaluation of water distribution system models shows that the matching principle does not match supply to demand in such systems. Furthermore, proof of the basic theorem is shown to require that the covariance of nutrient uptake and current path length is 0, an assumption unlikely to be true in mammalian arterial systems. Conclusion The supply-demand matching principle does not lead to a satisfactory explanation for the approximately 3/4-power scaling of mammalian basal metabolic rate.

Driving forces behind the Chinese public's demand for improved environmental safety.

Science.gov (United States)

Wen, Ting; Wang, Jigan; Ma, Zongwei; Bi, Jun

2017-12-15

Over the past decades, the public demand for improved environmental safety keeps increasing in China. This study aims to assess the driving forces behind the increasing public demand for improved environmental safety using a provincial and multi-year (1995, 2000, 2005, 2010, and 2014) panel data and the Stochastic Impacts by Regression on Population, Affluence, and Technology (STIRPAT) model. The potential driving forces investigated included population size, income levels, degrees of urbanization, and educational levels. Results show that population size and educational level are positively (Pdemand for improved environmental safety. No significant impact on demand was found due to the degree of urbanization. For the impact due to income level, an inverted U-shaped curve effect with the turning point of ~140,000 CNY GDP per capita is indicated. Since per capita GDP of 2015 in China was approximately 50,000 CNY and far from the turning point, the public demand for improved environmental safety will continue rising in the near future. To meet the increasing public demand for improved environmental safety, proactive and risk prevention based environmental management systems coupled with effective environmental risk communication should be established. Copyright © 2017 Elsevier B.V. All rights reserved.

Urban fuel demand in Ethiopia: an almost‐ideal demand system ...

African Journals Online (AJOL)

This paper investigates the opportunities for reducing the pressure of urban centers on rural forest areas, using a dataset of 350 urban households in Tigrai in northern Ethiopia. We applied an almost‐ideal demand system to fuels. The results suggest that reducing the pressure of urban centers on local forests cannot be ...

Decision on risk-averse dual-channel supply chain under demand disruption

Science.gov (United States)

Yan, Bo; Jin, Zijie; Liu, Yanping; Yang, Jianbo

2018-02-01

We studied dual-channel supply chains using centralized and decentralized decision-making models. We also conducted a comparative analysis of the decisions before and after demand disruption. The study shows that the amount of change in decision-making is a linear function of the amount of demand disruption, and it is independent of the risk-averse coefficient. The optimal sales volume decision of the disturbing supply chain is related to market share and demand disruption in the decentralized decision-making model. The optimal decision is only influenced by demand disruption in the centralized decision-making model. The stability of the sales volume of the two models is related to market share and demand disruption. The optimal system production of the two models shows robustness, but their stable internals are different.

A Probabilistic Short-Term Water Demand Forecasting Model Based on the Markov Chain

Directory of Open Access Journals (Sweden)

Francesca Gagliardi

2017-07-01

Full Text Available This paper proposes a short-term water demand forecasting method based on the use of the Markov chain. This method provides estimates of future demands by calculating probabilities that the future demand value will fall within pre-assigned intervals covering the expected total variability. More specifically, two models based on homogeneous and non-homogeneous Markov chains were developed and presented. These models, together with two benchmark models (based on artificial neural network and naïve methods, were applied to three real-life case studies for the purpose of forecasting the respective water demands from 1 to 24 h ahead. The results obtained show that the model based on a homogeneous Markov chain provides more accurate short-term forecasts than the one based on a non-homogeneous Markov chain, which is in line with the artificial neural network model. Both Markov chain models enable probabilistic information regarding the stochastic demand forecast to be easily obtained.

Estimating petroleum products demand elasticities in Nigeria. A multivariate cointegration approach

International Nuclear Information System (INIS)

Iwayemi, Akin; Adenikinju, Adeola; Babatunde, M. Adetunji

2010-01-01

This paper formulates and estimates petroleum products demand functions in Nigeria at both aggregative and product level for the period 1977 to 2006 using multivariate cointegration approach. The estimated short and long-run price and income elasticities confirm conventional wisdom that energy consumption responds positively to changes in GDP and negatively to changes in energy price. However, the price and income elasticities of demand varied according to product type. Kerosene and gasoline have relatively high short-run income and price elasticities compared to diesel. Overall, the results show petroleum products to be price and income inelastic. (author)

Estimating petroleum products demand elasticities in Nigeria. A multivariate cointegration approach

Energy Technology Data Exchange (ETDEWEB)

Iwayemi, Akin; Adenikinju, Adeola; Babatunde, M. Adetunji [Department of Economics, University of Ibadan, Ibadan (Nigeria)

2010-01-15

This paper formulates and estimates petroleum products demand functions in Nigeria at both aggregative and product level for the period 1977 to 2006 using multivariate cointegration approach. The estimated short and long-run price and income elasticities confirm conventional wisdom that energy consumption responds positively to changes in GDP and negatively to changes in energy price. However, the price and income elasticities of demand varied according to product type. Kerosene and gasoline have relatively high short-run income and price elasticities compared to diesel. Overall, the results show petroleum products to be price and income inelastic. (author)

Teacher Supply and Demand: Surprises from Primary Research

Directory of Open Access Journals (Sweden)

Andrew J. Wayne

2000-09-01

Full Text Available An investigation of primary research studies on public school teacher supply and demand revealed four surprises. Projections show that enrollments are leveling off. Relatedly, annual hiring increases should be only about two or three percent over the next few years. Results from studies of teacher attrition also yield unexpected results. Excluding retirements, only about one in 20 teachers leaves each year, and the novice teachers who quit mainly cite personal and family reasons, not job dissatisfaction. Each of these findings broadens policy makers' options for teacher supply.

Demand for power in Calcutta Electricity Supply Corporation area

Energy Technology Data Exchange (ETDEWEB)

Banerjee, N

1980-07-01

Since the early 1970's there has been a continuous crisis of power supply to the Calcutta industrial region. Historical records show that only the peak demand has grown and has a potential for growth, which, with an unchanging base demand, results in a low load factor and consequently inefficient power system operation. Attempts to shift industrial loads by operating industrial plants during non-peak hours are described. Adverse economic conditions eliminated the need for extra working shifts. It is concluded that the power system supplying the Calcutta region has an insufficient peak load generating capacity and an uneconomic load curve and that stricter hourly schedules for power use by industries should be adhered to in order to minimize these problems. (LCL)

Two-stage stochastic programming model for the regional-scale electricity planning under demand uncertainty

International Nuclear Information System (INIS)

Huang, Yun-Hsun; Wu, Jung-Hua; Hsu, Yu-Ju

2016-01-01

Traditional electricity supply planning models regard the electricity demand as a deterministic parameter and require the total power output to satisfy the aggregate electricity demand. But in today's world, the electric system planners are facing tremendously complex environments full of uncertainties, where electricity demand is a key source of uncertainty. In addition, electricity demand patterns are considerably different for different regions. This paper developed a multi-region optimization model based on two-stage stochastic programming framework to incorporate the demand uncertainty. Furthermore, the decision tree method and Monte Carlo simulation approach are integrated into the model to simplify electricity demands in the form of nodes and determine the values and probabilities. The proposed model was successfully applied to a real case study (i.e. Taiwan's electricity sector) to show its applicability. Detail simulation results were presented and compared with those generated by a deterministic model. Finally, the long-term electricity development roadmap at a regional level could be provided on the basis of our simulation results. - Highlights: • A multi-region, two-stage stochastic programming model has been developed. • The decision tree and Monte Carlo simulation are integrated into the framework. • Taiwan's electricity sector is used to illustrate the applicability of the model. • The results under deterministic and stochastic cases are shown for comparison. • Optimal portfolios of regional generation technologies can be identified.

Estimation of urban residential electricity demand in China using household survey data

International Nuclear Information System (INIS)

Zhou, Shaojie; Teng, Fei

2013-01-01

This paper uses annual urban household survey data of Sichuan Province from 2007 to 2009 to estimate the income and price elasticities of residential electricity demand, along with the effects of lifestyle-related variables. The empirical results show that in the urban area of Sichuan province, the residential electricity demand is price- and income-inelastic, with price and income elasticities ranging from −0.35 to −0.50 and from 0.14 to 0.33, respectively. Such lifestyle-related variables as demographic variables, dwelling size and holdings of home appliances, are also important determinants of residential electricity demand, especially the latter. These results are robust to a variety of sensitivity tests. The research findings imply that urban residential electricity demand continues to increase with the growth of income. The empirical results have important policy implications for the Multistep Electricity Price, which been adopted in some cities and is expected to be promoted nationwide through the installation of energy-efficient home appliances. - Highlights: • We estimate price and income elasticities in China using household survey data. • The current study is the first such study in China at this level. • Both price and income are inelastic. • Behavior factors have important impact on electricity consumption

Hierarchical prediction of industrial water demand based on refined Laspeyres decomposition analysis.

Science.gov (United States)

Shang, Yizi; Lu, Shibao; Gong, Jiaguo; Shang, Ling; Li, Xiaofei; Wei, Yongping; Shi, Hongwang

2017-12-01

A recent study decomposed the changes in industrial water use into three hierarchies (output, technology, and structure) using a refined Laspeyres decomposition model, and found monotonous and exclusive trends in the output and technology hierarchies. Based on that research, this study proposes a hierarchical prediction approach to forecast future industrial water demand. Three water demand scenarios (high, medium, and low) were then established based on potential future industrial structural adjustments, and used to predict water demand for the structural hierarchy. The predictive results of this approach were compared with results from a grey prediction model (GPM (1, 1)). The comparison shows that the results of the two approaches were basically identical, differing by less than 10%. Taking Tianjin, China, as a case, and using data from 2003-2012, this study predicts that industrial water demand will continuously increase, reaching 580 million m 3 , 776.4 million m 3 , and approximately 1.09 billion m 3 by the years 2015, 2020 and 2025 respectively. It is concluded that Tianjin will soon face another water crisis if no immediate measures are taken. This study recommends that Tianjin adjust its industrial structure with water savings as the main objective, and actively seek new sources of water to increase its supply.

Asian oil demand

International Nuclear Information System (INIS)

Fesharaki, F.

2005-01-01

This conference presentation examined global oil market development and the role of Asian demand. It discussed plateau change versus cyclical movement in the global oil market; supply and demand issues of OPEC and non-OPEC oil; if high oil prices reduce demand; and the Asian oil picture in the global context. Asian oil demand has accounted for about 50 per cent of the global incremental oil market growth. The presentation provided data charts in graphical format on global and Asia-Pacific incremental oil demand from 1990-2005; Asia oil demand growth for selected nations; real GDP growth in selected Asian countries; and, Asia-Pacific oil production and net import requirements. It also included charts in petroleum product demand for Asia-Pacific, China, India, Japan, and South Korea. Other data charts included key indicators for China's petroleum sector; China crude production and net oil import requirements; China's imports and the share of the Middle East; China's oil exports and imports; China's crude imports by source for 2004; China's imports of main oil products for 2004; India's refining capacity; India's product balance for net-imports and net-exports; and India's trade pattern of oil products. tabs., figs

Long-term outlook of energy demand and supply in Japan. Estimation of energy demand and supply for 'Nuclear Energy Vision 2100' of JAEA

International Nuclear Information System (INIS)

Tatematsu, Kenji; Kawasaki, Hirotsugu; Nemoto, Masahiro; Murakami, Masakazu

2009-06-01

In this study, we showed an energy demand and supply scenario toward the year 2100 in Japan, which underlies JAEA's 'Nuclear Energy Vision 2100' published in October 2008. This energy demand and supply scenario aimed at the coexistence of the reduction of the carbon dioxide emission and the energy security through reduction of the fossil fuel usage, positive electrification and the nuclear energy usage. We reduced the ratio of the fossil fuel in the primary energy supply to about 1/3 and extend the share of renewable and nuclear energy to 70% from current 15%. As a result, the carbon dioxide emission was reduced to current 10%, and it developed that the half was the contribution of the nuclear energy. (author)

The UFE Prospective scenarios for energy demand

International Nuclear Information System (INIS)

2013-01-01

After an overview of the French energy consumption in 2011 (final energy consumption, distribution of CO 2 emissions related to energy consumption), this Power Point presentation proposes graphs and figures illustrating UFE's prospective scenarios for energy demand. The objective is to foresee energy demand in 2050, to study the impact of possible actions on energy demand, and to assess the impact on greenhouse gas emissions. Hypotheses relate to demographic evolution, economic growth, energy intensity evolution, energy efficiency, and use transfers. Factors of evolution of energy demand are discussed: relationship between demography and energy consumption, new uses of electricity (notably with TICs), relationship between energy intensity and economic growth. Actions on demand are discussed. The results of different scenarios of technical evolution are presented

Forecasting Electricity Demand in Thailand with an Artificial Neural Network Approach

Directory of Open Access Journals (Sweden)

Karin Kandananond

2011-08-01

Full Text Available Demand planning for electricity consumption is a key success factor for the development of any countries. However, this can only be achieved if the demand is forecasted accurately. In this research, different forecasting methods—autoregressive integrated moving average (ARIMA, artificial neural network (ANN and multiple linear regression (MLR—were utilized to formulate prediction models of the electricity demand in Thailand. The objective was to compare the performance of these three approaches and the empirical data used in this study was the historical data regarding the electricity demand (population, gross domestic product: GDP, stock index, revenue from exporting industrial products and electricity consumption in Thailand from 1986 to 2010. The results showed that the ANN model reduced the mean absolute percentage error (MAPE to 0.996%, while those of ARIMA and MLR were 2.80981 and 3.2604527%, respectively. Based on these error measures, the results indicated that the ANN approach outperformed the ARIMA and MLR methods in this scenario. However, the paired test indicated that there was no significant difference among these methods at α = 0.05. According to the principle of parsimony, the ARIMA and MLR models might be preferable to the ANN one because of their simple structure and competitive performance

Resource Demand Scenarios for the Major Metals.

Science.gov (United States)

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.

Supply- and demand-side effects of power sector planning with demand-side management options and SO2 emission constraints

International Nuclear Information System (INIS)

Shrestha, R.M.; Marpaung, C.O.P.

2005-01-01

This paper examines the implications of SO 2 emission mitigation constraints in the power sector planning in Indonesia--a developing country--during 2003-2017 from a long term integrated resource planning perspective. A decomposition model is developed to assess the contributions of supply- and demand-side effects to the total changes in CO 2 , SO 2 and NO x emissions from the power sector due to constraints on SO 2 emissions. The results of the study show that both the supply- and demand-side effects would act towards the reduction of CO 2 , SO 2 and NO x emissions. However, the supply-side effect would play the dominant role in emission mitigations from the power sector in Indonesia. The average incremental SO 2 abatement cost would increase from US$ 970 to US$ 1271 per ton of SO 2 , while electricity price would increase by 2-18% if the annual SO 2 emission reduction target is increased from 10% to 25%

Centrifuges help match supply and demand

International Nuclear Information System (INIS)

Crossley, P.S.

1980-01-01

Since the early 1970's the enrichment market situation has changed dramatically. Falling demands and increasing production capacity has resulted in over-capacity and stockpiles of enriched uranium. New trends in the industry are considered by analysing the following issues: supply and demand; technical development; build-up plans; contracting policies; enrichment economics; and nuclear safeguards. (U.K.)

Factors Influencing Compensation Demanded for Environmental Impacts Generated by Different Economic Activities

Directory of Open Access Journals (Sweden)

Virna Vaneza Gutiérrez

2015-07-01

Full Text Available This work advances the understanding of compensation demanded for environmental impacts on atmosphere, lakes and rivers, soil, and ocean generated by mining, urban, fishing and agriculture activities. Our aims are to determine whether compensation demanded depends on the standard variables used in the field of risk perception (as perceived risk, public acceptability and trust in regulating authorities, and to explore whether these relationships depend on the environment affected and on the economic activity generating the impacts. General Linear Models were used to analyze survey responses from 427 citizens of Santiago, Chile. Results showed that compensation demanded depends on perceived risk, acceptability, and on the economic activity, but not on the environment affected. Acceptability depends on trust in authorities, on perceived risk and on the economic activity. Perceived risk depends on trust, the economic activity and the environment affected. Overall, environmental impacts from the mining industry are perceived as riskier, less acceptable, and have a higher compensation demanded than those generated by the other sectors. These results suggest that to achieve sustainable development, regulations should consider not only environmental impacts but also the economic activity originating them.

Addictive behavior in cinema demand: evidence from Korea

OpenAIRE

Sangho KIM; Donghyun PARK

2010-01-01

It is intuitively plausible that the demand for cinema services may be partly driven by addiction or habit. Yet there is almost no empirical literature which tests for whether cinema demand is addictive. We estimate addiction models for cinema demand using Korean time series data from 1963 to 2004. Our estimation results indicate that (i) addictive behavior characterizes the demand for cinema services, (ii) this behavior is rational, and (iii) habit is one of most important determinants of ci...

Acceleration in the care of older adults: new demands as predictors of employee burnout and engagement.

Science.gov (United States)

Kubicek, Bettina; Korunka, Christian; Ulferts, Heike

2013-07-01

This paper introduces the concept of acceleration-related demands in the care of older adults. It examines these new demands and their relation to cognitive, emotional, and physical job demands and to employee well-being. Various changes in the healthcare systems of Western societies pose new demands for healthcare professionals' careers and jobs. In particular today's societal changes give rise to acceleration-related demands, which manifest themselves in work intensification and in increasing requirements to handle new technical equipment and to update one's job-related knowledge. It is, therefore, of interest to investigate the effects of these new demands on the well-being of employees. Survey. Between March-June 2010 the survey was conducted among healthcare professionals involved in care of older adults in Austria. A total of 1498 employees provided data on cognitive, emotional, and physical job demands and on acceleration-related demands. The outcome variables were the core dimensions of burnout (emotional exhaustion and depersonalization) and engagement (vigour and dedication). Hierarchical regression analyses show that acceleration-related demands explain additional variance for exhaustion, depersonalization, vigour, and dedication when controlling for cognitive, emotional, and physical demands. Furthermore, acceleration-related demands associated with increasing requirements to update one's knowledge are related to positive outcomes (vigour and dedication). Acceleration-related demands associated with an increasing work pace are related to negative outcomes such as emotional exhaustion. Results illustrate that new demands resulting from social acceleration generate potential challenges for on-the-job learning and potential risks to employees' health and well-being. © 2012 Blackwell Publishing Ltd.

Consumer demand and quality assurance

DEFF Research Database (Denmark)

Grunert, Klaus G; Wognum, Nel; Trienekens, Jacques

2011-01-01

Consumers differ in their demands, and this mau have implications for the type of supply chain governance that is most suitable for serving them. We present a segmentation of pork consumers in the EU based on their food-related lifestyles and demand for different pork products. We then present...... an inventory of pork chain governance and quality management systems, also resulting from a pan-European study, and attempt to match types of chains to consumer segments, arguing that the type of quality demanded by the consumers has implications especially for the quality management system governing the chain......, and that these implications are different for fresh meat and processed meat. The paper closes with a call for more collaboration between chain researchers and consumer researchers....

Supply-demand controls the futures

International Nuclear Information System (INIS)

Brown, D.

1991-01-01

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

A methodology for the assessment of potential demand and optimal supply of entrepreneurial microcredit

Directory of Open Access Journals (Sweden)

Ayi Gavriel Ayayi

2012-04-01

Full Text Available We propose a methodology for the assessment of potential demand and optimal supply for microcredit. We show that the total demand is a combination of the demand that stems from the active poor plus the demand generated by a motivator agent among the entrepreneurial non-motivated poor. We use French data to provide an illustration of the assessment of potential demand for microcredit. We also show that the proportion of the potential demand satisfied by a microfinance institution depends on its objective i.e. either it is socially oriented or a profit maximizer.

Competence-based demands made of senior physicians: an empirical study to evaluate leadership competencies.

Science.gov (United States)

Lehr, Bosco; Ostermann, Herwig; Schubert, Harald

2011-01-01

As a result of more economising in German hospitals, changes evolve in organising the deployment of senior medical staff. New demands are made of senior hospital management. Leadership competencies in the training and development of physicians are of prime importance to the successful perception of managerial responsibilities. The present study investigates the actual and targeted demands of leadership made of senior medical staff in terms of how these demands are perceived. To this end, the demands of leadership were surveyed using a competence-based questionnaire and investigated with a view to potentials in professional development by way of example of the senior management of psychiatric hospitals in Germany. In all, the results show high ratings in personal performance, the greatest significance being attributed to value-oriented competence in the actual assessment of demands on leadership. Besides gender-specific differences in the actual assessments of single fields of competence, the greatest differences between the targeted and the actual demands are, in all, shown to be in the competencies of self-management and communication. Competence-based core areas in leadership can be demonstrated for the professional development of physicians and an adaptive mode of procedure deduced. Copyright © 2010. Published by Elsevier GmbH.

Identifying rural-urban differences in the predictors of emergency ambulance service demand and misuse.

Science.gov (United States)

Wong, Ho Ting; Lin, Teng-Kang; Lin, Jen-Jia

2018-06-13

This study aims to assess rural-urban differences in the predictors of emergency ambulance service (EAS) demand and misuse in New Taipei City. Identifying the predictors of EAS demand will help the EAS service managing authority in formulating focused policies to maintain service quality. Over 160,000 electronic EAS usage records were used with a negative binomial regression model to assess rural-urban differences in the predictors of EAS demand and misuse. The factors of 1) ln-transformed population density, 2) percentage of residents who completed up to junior high school education, 3) accessibility of hospitals without an emergency room, and 4) accessibility of EAS were found to be predictors of EAS demand in rural areas, whereas only the factor of percentage of people aged above 65 was found to predict EAS demand in urban areas. For EAS misuse, only the factor of percentage of low-income households was found to be a predictor in rural areas, whereas no predictor was found in the urban areas. Results showed that the factors predicting EAS demand and misuse in rural areas were more complicated compared to urban areas and, therefore, formulating EAS policies for rural areas based on the results of urban studies may not be appropriate. Copyright © 2018. Published by Elsevier B.V.

Tourist Demand Reactions: Symmetric or Asymmetric across the Business Cycle?

Science.gov (United States)

Bronner, Fred; de Hoog, Robert

2017-09-01

Economizing and spending priorities on different types of vacations are investigated during two periods: an economic downturn and returning prosperity. Two nation-wide samples of vacationers are used: one during a downturn, the other one at the start of the recovery period. Through comparing the results, conclusions can be drawn about symmetric or asymmetric tourist demand across the business cycle. The main summer holiday has an asymmetric profile: being fairly crisis-resistant during a recession and showing considerable growth during an expansion. This does not apply to short vacations and day trips, each having a symmetric profile: during a recession they experience substantial reductions and during expansion comparable growth. So when talking about tourist demand in general , one cannot say that it is symmetric or asymmetric across the business cycle: it depends on the type of vacation. Differences in tourist demand are best explained by the role of Quality-of-Life for vacationers.

Fuel switching in Harare: An almost ideal demand system approach

International Nuclear Information System (INIS)

Chambwera, Muyeye; Folmer, Henk

2007-01-01

In urban areas several energy choices are available and the amount of (a given type of) fuel consumed is based on complex household decision processes. This paper analyzes urban fuel (particularly firewood) demand in an energy mix context by means of an Almost Ideal Demand System based on a survey carried out among 500 households in Harare in 2003. Using a multi-stage budgeting approach, the model estimates the share of energy in total household expenditure and the shares of firewood, electricity and kerosene in total energy expenditure. Using the model results simulations show that the main policy handles to reduce the demand for firewood and to mitigate environmental degradation such as deforestation include decreasing prices of alternative fuels, notably kerosene. Moreover, in the long run sound economic policy will positively impact on the energy budget whereas education and the degree of electrification will contribute to a reduction of the use of firewood

Province gets serious about demand management

International Nuclear Information System (INIS)

Anon

2003-01-01

Directives from the Minister to the Ontario Energy Board to review options for demand-side management and demand reduction activities, and discussion papers describing the policy framework needed to implement demand management, are indications of renewed interest by the provincial government in demand-side management of Ontario's electric power supply. This renewed interest comes on the hills of a 5.5 per cent increase in electricity use, a 33 per cent increase in imports, and consumption records broken in 10 of the last 12 months. A 117-page study was released in April by Navigant Consulting, entitled 'Demand response blueprint for Ontario' which estimates that if the Ontario market had 250 MW of additional demand response, customers providing the demand response would have saved $20 million by reducing their demand when HOEP was greater than $120/MWh, while other customers would have saved $170 million due to lower HOEP, and would have enjoyed greater reliability as a result of the increase in reserve margins. Other than price signals to induce customers to save, the Navigant report suggest paying customers not to consume during peak periods. The report estimates that such a policy could generate a total demand response of 350 MW and a $235 million reduction in revenue to generators. The Navigan report also includes a large number of detailed analysis and recommendations. One among them is for the extensive use of interval meters for customers with loads over 200 kW. The report tends to be critical of the recent price freeze ordered by the Ontario government, claiming that the freeze could increase consumption, making prices more volatile and increasing the cost to the government even more. Successful demand response programs from California, New York and the New England states are cited as examples for Ontario to emulate

Safety behavior: Job demands, job resources, and perceived management commitment to safety.

Science.gov (United States)

Hansez, Isabelle; Chmiel, Nik

2010-07-01

The job demands-resources model posits that job demands and resources influence outcomes through job strain and work engagement processes. We test whether the model can be extended to effort-related "routine" safety violations and "situational" safety violations provoked by the organization. In addition we test more directly the involvement of job strain than previous studies which have used burnout measures. Structural equation modeling provided, for the first time, evidence of predicted relationships between job strain and "routine" violations and work engagement with "routine" and "situational" violations, thereby supporting the extension of the job demands-resources model to safety behaviors. In addition our results showed that a key safety-specific construct 'perceived management commitment to safety' added to the explanatory power of the job demands-resources model. A predicted path from job resources to perceived management commitment to safety was highly significant, supporting the view that job resources can influence safety behavior through both general motivational involvement in work (work engagement) and through safety-specific processes.

Sets in Excess Demand in Ascending Auctions with Unit-Demand Bidders

NARCIS (Netherlands)

Andersson, T.D.; Andersson, C.; Talman, A.J.J.

2010-01-01

This paper analyzes the problem of selling a number of indivisible items to a set of unitdemand bidders. An ascending auction mechanism called the Excess Demand Ascending Auction (EDAA) is defined. The main results demonstrate that EDAA terminates in a finite number of iterations and that the exact

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

Science.gov (United States)

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

2016-01-01

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

Demand elasticity increase for reducing social welfare losses due to transfer capacity restriction: A test case on Italian cross-border imports

International Nuclear Information System (INIS)

Bruno, Sergio; De Benedictis, Michele; La Scala, Massimo; Wangensteen, Ivar

2006-01-01

The paper is aimed at showing how demand-side policies for increasing inner demand elasticity could help in reducing market inefficiencies generated by transfer limits on interconnections, with a special regard to energy imports dependent countries. In order to develop the studies in a realistic environment, a model for the Italian electricity market has been developed. Test results show effects of variations in demand elasticity on the national social surplus and congestion costs. It will be shown how an increase of demand elasticity can counterbalance the need of additional transfer capacity in reducing cross-border congestions. (author)

Quality-driven methodology for demanding accelarator design

NARCIS (Netherlands)

Jozwiak, L.; Jan, Y.

2010-01-01

This paper focuses on mastering the architecture development of hardware accelerators for demanding applications. It presents the results of our analysis of the main problems that have to be solved when designing accelerators for modern demanding applications, and illustrates the problems with an

Elucidating the role of recovery experiences in the job demands-resources model.

Science.gov (United States)

Moreno-Jiménez, Bernardo; Rodríguez-Muñoz, Alfredo; Sanz-Vergel, Ana Isabel; Garrosa, Eva

2012-07-01

Based on the Job Demands-Resources (JD-R) model, the current study examined the moderating role of recovery experiences (i.e., psychological detachment from work, relaxation, mastery experiences, and control over leisure time) on the relationship between one job demand (i.e., role conflict) and work- and health-related outcomes. Results from our sample of 990 employees from Spain showed that psychological detachment from work and relaxation buffered the negative impact of role conflict on some of the proposed outcomes. Contrary to our expectations, we did not find significant results for mastery and control regarding moderating effects. Overall, findings suggest a differential pattern of the recovery experiences in the health impairment process proposed by the JD-R model.

Forecasting domestic water demand in the Haihe river basin under changing environment

Science.gov (United States)

Wang, Xiao-Jun; Zhang, Jian-Yun; Shahid, Shamsuddin; Xie, Yu-Xuan; Zhang, Xu

2018-02-01

A statistical model has been developed for forecasting domestic water demand in Haihe river basin of China due to population growth, technological advances and climate change. Historical records of domestic water use, climate, population and urbanization are used for the development of model. An ensemble of seven general circulation models (GCMs) namely, BCC-CSM1-1, BNU-ESM, CNRM-CM5, GISS-E2-R, MIROC-ESM, PI-ESM-LR, MRI-CGCM3 were used for the projection of climate and the changes in water demand in the Haihe River basin under Representative Concentration Pathways (RCPs) 4.5. The results showed that domestic water demand in different sub-basins of the Haihe river basin will gradually increase due to continuous increase of population and rise in temperature. It is projected to increase maximum 136.22 × 108 m3 by GCM BNU-ESM and the minimum 107.25 × 108 m3 by CNRM-CM5 in 2030. In spite of uncertainty in projection, it can be remarked that climate change and population growth would cause increase in water demand and consequently, reduce the gap between water supply and demand, which eventually aggravate the condition of existing water stress in the basin. Water demand management should be emphasized for adaptation to ever increasing water demand and mitigation of the impacts of environmental changes.

Impact of onsite solar generation on system load demand forecast

International Nuclear Information System (INIS)

Kaur, Amanpreet; Pedro, Hugo T.C.; Coimbra, Carlos F.M.

2013-01-01

Highlights: • We showed the impact onsite solar generation on system demand load forecast. • Forecast performance degrades by 9% and 3% for 1 h and 15 min forecast horizons. • Error distribution for onsite case is best characterized as t-distribution. • Relation between error, solar penetration and solar variability is characterized. - Abstract: Net energy metering tariffs have encouraged the growth of solar PV in the distribution grid. The additional variability associated with weather-dependent renewable energy creates new challenges for power system operators that must maintain and operate ancillary services to balance the grid. To deal with these issues power operators mostly rely on demand load forecasts. Electric load forecast has been used in power industry for a long time and there are several well established load forecasting models. But the performance of these models for future scenario of high renewable energy penetration is unclear. In this work, the impact of onsite solar power generation on the demand load forecast is analyzed for a community that meets between 10% and 15% of its annual power demand and 3–54% of its daily power demand from a solar power plant. Short-Term Load Forecasts (STLF) using persistence, machine learning and regression-based forecasting models are presented for two cases: (1) high solar penetration and (2) no penetration. Results show that for 1-h and 15-min forecasts the accuracy of the models drops by 9% and 3% with high solar penetration. Statistical analysis of the forecast errors demonstrate that the error distribution is best characterized as a t-distribution for the high penetration scenario. Analysis of the error distribution as a function of daily solar penetration for different levels of variability revealed that the solar power variability drives the forecast error magnitude whereas increasing penetration level has a much smaller contribution. This work concludes that the demand forecast error distribution

Empirical analysis of the spot market implications of price-responsive demand

International Nuclear Information System (INIS)

Siddiqui, A.S.

2006-01-01

Although electricity is theoretically an inelastic good in the short term, the steep slope of the supply stack implies that even modest response by demand could translate into reduced capacity requirements and significant price decreases. This article examined the effect of price-responsive demand strategies in an actual deregulated electricity industry. Auction data from the New York Independent System Operator (NYISO) day-ahead electricity market were used to form supply stacks for various zones. A simple linear demand function was used to determine the effect of price responsiveness on equilibrium spot market price and consumption. The aim was to quantify the benefits from the pricing protocol and to determine whether modest levels of price elasticity can significantly lower prices and consumption. Market-clearing prices and quantities were estimated using various supply curves in order to quantify the responsiveness necessary to achieve given price reductions. Price response was induced in the demand curve by varying its slope. Estimates were then used to estimate the average level of slope needed to reduce the average market-clearing price during the year by a certain percentage. Results showed that an average slope of -50.04 was necessary for prices to be reduced by 25 per cent. Results also showed that necessary price responses can be ascertained for any desired reduction in the market-clearing price or quantity. Although price responsiveness unambiguously reduces the spot market price and quantity, its effect on the forward price is not yet clear. It was concluded that a separate analysis of peak hours may reveal the effectiveness of enhanced price response. 8 refs., 1 tab., 8 figs

The energy demand in the Narino Department

International Nuclear Information System (INIS)

Unidad de Planeacion Minero Energetica, UPME

2000-01-01

In the object of making a first approach of regional energy requirements analysis and the good way of satisfying them, the UPME undertook a global energy study for the Narino Department. In this study (UPME 1999) was carried out an analysis of the energy demand and of the socioeconomic factors that determine it; they were also studied the consumptions and the current energy offer and the alternatives of future evolution, with the purpose of having the basic tools of a departmental energy plan. The present article refers specifically to the analysis of the demand and it seeks to show the readers the complexity and the volume of necessary information to carry out the demand studies. They are multiple factors that determine the energy demand in the Narino Department. The size, growth populations, geographical distribution and cultural characteristic, the border condition, the faulty infrastructure of communications, the agricultural economic structure and the low entrance per capita

Correlation Analysis of Water Demand and Predictive Variables for Short-Term Forecasting Models

Directory of Open Access Journals (Sweden)

B. M. Brentan

2017-01-01

Full Text Available Operational and economic aspects of water distribution make water demand forecasting paramount for water distribution systems (WDSs management. However, water demand introduces high levels of uncertainty in WDS hydraulic models. As a result, there is growing interest in developing accurate methodologies for water demand forecasting. Several mathematical models can serve this purpose. One crucial aspect is the use of suitable predictive variables. The most used predictive variables involve weather and social aspects. To improve the interrelation knowledge between water demand and various predictive variables, this study applies three algorithms, namely, classical Principal Component Analysis (PCA and machine learning powerful algorithms such as Self-Organizing Maps (SOMs and Random Forest (RF. We show that these last algorithms help corroborate the results found by PCA, while they are able to unveil hidden features for PCA, due to their ability to cope with nonlinearities. This paper presents a correlation study of three district metered areas (DMAs from Franca, a Brazilian city, exploring weather and social variables to improve the knowledge of residential demand for water. For the three DMAs, temperature, relative humidity, and hour of the day appear to be the most important predictive variables to build an accurate regression model.

A supply and demand based volatility model for energy prices

International Nuclear Information System (INIS)

Kanamura, Takashi

2009-01-01

This paper proposes a new volatility model for energy prices using the supply-demand relationship, which we call a supply and demand based volatility model. We show that the supply curve shape in the model determines the characteristics of the volatility in energy prices. It is found that the inverse Box-Cox transformation supply curve reflecting energy markets causes the inverse leverage effect, i.e., positive correlation between energy prices and volatility. The model is also used to show that an existing (G)ARCH-M model has the foundations on the supply-demand relationship. Additionally, we conduct the empirical studies analyzing the volatility in the U.S. natural gas prices. (author)

A supply and demand based volatility model for energy prices

Energy Technology Data Exchange (ETDEWEB)

Kanamura, Takashi [J-POWER, 15-1, Ginza 6-Chome, Chuo-ku, Tokyo 104-8165 (Japan)

2009-09-15

This paper proposes a new volatility model for energy prices using the supply-demand relationship, which we call a supply and demand based volatility model. We show that the supply curve shape in the model determines the characteristics of the volatility in energy prices. It is found that the inverse Box-Cox transformation supply curve reflecting energy markets causes the inverse leverage effect, i.e., positive correlation between energy prices and volatility. The model is also used to show that an existing (G)ARCH-M model has the foundations on the supply-demand relationship. Additionally, we conduct the empirical studies analyzing the volatility in the U.S. natural gas prices. (author)

Separation of metabolic supply and demand: aerobic glycolysis as a normal physiological response to fluctuating energetic demands in the membrane.

Science.gov (United States)

Epstein, Tamir; Xu, Liping; Gillies, Robert J; Gatenby, Robert A

2014-01-01

Cancer cells, and a variety of normal cells, exhibit aerobic glycolysis, high rates of glucose fermentation in the presence of normal oxygen concentrations, also known as the Warburg effect. This metabolism is considered abnormal because it violates the standard model of cellular energy production that assumes glucose metabolism is predominantly governed by oxygen concentrations and, therefore, fermentative glycolysis is an emergency back-up for periods of hypoxia. Though several hypotheses have been proposed for the origin of aerobic glycolysis, its biological basis in cancer and normal cells is still not well understood. We examined changes in glucose metabolism following perturbations in membrane activity in different normal and tumor cell lines and found that inhibition or activation of pumps on the cell membrane led to reduction or increase in glycolysis, respectively, while oxidative phosphorylation remained unchanged. Computational simulations demonstrated that these findings are consistent with a new model of normal physiological cellular metabolism in which efficient mitochondrial oxidative phosphorylation supplies chronic energy demand primarily for macromolecule synthesis and glycolysis is necessary to supply rapid energy demands primarily to support membrane pumps. A specific model prediction was that the spatial distribution of ATP-producing enzymes in the glycolytic pathway must be primarily localized adjacent to the cell membrane, while mitochondria should be predominantly peri-nuclear. The predictions were confirmed experimentally. Our results show that glycolytic metabolism serves a critical physiological function under normoxic conditions by responding to rapid energetic demand, mainly from membrane transport activities, even in the presence of oxygen. This supports a new model for glucose metabolism in which glycolysis and oxidative phosphorylation supply different types of energy demand. Cells use efficient but slow-responding aerobic metabolism

Blockchain Based Decentralized Management of Demand Response Programs in Smart Energy Grids

Science.gov (United States)

Pop, Claudia; Cioara, Tudor; Antal, Marcel; Anghel, Ionut; Salomie, Ioan; Bertoncini, Massimo

2018-01-01

In this paper, we investigate the use of decentralized blockchain mechanisms for delivering transparent, secure, reliable, and timely energy flexibility, under the form of adaptation of energy demand profiles of Distributed Energy Prosumers, to all the stakeholders involved in the flexibility markets (Distribution System Operators primarily, retailers, aggregators, etc.). In our approach, a blockchain based distributed ledger stores in a tamper proof manner the energy prosumption information collected from Internet of Things smart metering devices, while self-enforcing smart contracts programmatically define the expected energy flexibility at the level of each prosumer, the associated rewards or penalties, and the rules for balancing the energy demand with the energy production at grid level. Consensus based validation will be used for demand response programs validation and to activate the appropriate financial settlement for the flexibility providers. The approach was validated using a prototype implemented in an Ethereum platform using energy consumption and production traces of several buildings from literature data sets. The results show that our blockchain based distributed demand side management can be used for matching energy demand and production at smart grid level, the demand response signal being followed with high accuracy, while the amount of energy flexibility needed for convergence is reduced. PMID:29315250

Blockchain Based Decentralized Management of Demand Response Programs in Smart Energy Grids.

Science.gov (United States)

Pop, Claudia; Cioara, Tudor; Antal, Marcel; Anghel, Ionut; Salomie, Ioan; Bertoncini, Massimo

2018-01-09

In this paper, we investigate the use of decentralized blockchain mechanisms for delivering transparent, secure, reliable, and timely energy flexibility, under the form of adaptation of energy demand profiles of Distributed Energy Prosumers, to all the stakeholders involved in the flexibility markets (Distribution System Operators primarily, retailers, aggregators, etc.). In our approach, a blockchain based distributed ledger stores in a tamper proof manner the energy prosumption information collected from Internet of Things smart metering devices, while self-enforcing smart contracts programmatically define the expected energy flexibility at the level of each prosumer, the associated rewards or penalties, and the rules for balancing the energy demand with the energy production at grid level. Consensus based validation will be used for demand response programs validation and to activate the appropriate financial settlement for the flexibility providers. The approach was validated using a prototype implemented in an Ethereum platform using energy consumption and production traces of several buildings from literature data sets. The results show that our blockchain based distributed demand side management can be used for matching energy demand and production at smart grid level, the demand response signal being followed with high accuracy, while the amount of energy flexibility needed for convergence is reduced.

Blockchain Based Decentralized Management of Demand Response Programs in Smart Energy Grids

Directory of Open Access Journals (Sweden)

Claudia Pop

2018-01-01

Full Text Available In this paper, we investigate the use of decentralized blockchain mechanisms for delivering transparent, secure, reliable, and timely energy flexibility, under the form of adaptation of energy demand profiles of Distributed Energy Prosumers, to all the stakeholders involved in the flexibility markets (Distribution System Operators primarily, retailers, aggregators, etc.. In our approach, a blockchain based distributed ledger stores in a tamper proof manner the energy prosumption information collected from Internet of Things smart metering devices, while self-enforcing smart contracts programmatically define the expected energy flexibility at the level of each prosumer, the associated rewards or penalties, and the rules for balancing the energy demand with the energy production at grid level. Consensus based validation will be used for demand response programs validation and to activate the appropriate financial settlement for the flexibility providers. The approach was validated using a prototype implemented in an Ethereum platform using energy consumption and production traces of several buildings from literature data sets. The results show that our blockchain based distributed demand side management can be used for matching energy demand and production at smart grid level, the demand response signal being followed with high accuracy, while the amount of energy flexibility needed for convergence is reduced.

How are changes in exposure to job demands and job resources related to burnout and engagement? A longitudinal study among Chinese nurses and police officers.

Science.gov (United States)

Hu, Qiao; Schaufeli, Wilmar B; Taris, Toon W

2017-12-01

This study used a person-centered approach to examine the across-time relationships between job demands and job resources on the one hand and employee well-being (burnout and work engagement) on the other. On the basis of the job demands-resources model and conservation of resources (COR) theory, increases in demands and decreases in resources across time were expected to result in unfavorable changes in well-being across time. The results of a 2-wave study among 172 nurses and 273 police officers showed several common patterns across both samples: (a) participants who experienced an increase of demands showed a significant increase in burnout, whereas participants who reported having low resources at both measurement times also showed a significant increase in burnout; (b) participants who experienced decreasing resources reported a significant increase in burnout and a significant decrease in engagement; (c) participants who were exposed to chronic low job resources in a highly demanding environment showed a significant increase in burnout; and (d) participants who were exposed to decreased job resources in a highly demanding environment showed a significant increase in burnout. Copyright © 2017 John Wiley & Sons, Ltd.

Demand curves for hypothetical cocaine in cocaine-dependent individuals.

Science.gov (United States)

Bruner, Natalie R; Johnson, Matthew W

2014-03-01

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

PERFECT DEMAND ILLUSION

Directory of Open Access Journals (Sweden)

Alexander Yu. Sulimov

2015-01-01

Full Text Available The article is devoted to technique «Perfect demand illusion», which allows to strengthen the competitive advantageof retailers. Also in the paper spells out the golden rules of visual merchandising.The definition of the method «Demand illusion», formulated the conditions of its functioning, and is determined by the mainhypothesis of the existence of this method.Furthermore, given the definition of the «Perfect demand illusion», and describes its additional conditions. Also spells out the advantages of the «Perfect demandillusion», before the «Demand illusion».

Aviation Frontiers: On-Demand Aircraft

Science.gov (United States)

Moore, Mark D.

2010-01-01

Throughout the 20th Century, NASA has defined the forefront of aeronautical technology, and the aviation industry owes much of its prosperity to this knowledge and technology. In recent decades, centralized aeronautics has become a mature discipline, which raises questions concerning the future aviation innovation frontiers. Three transformational aviation capabilities, bounded together by the development of a Free Flight airspace management system, have the potential to transform 21st Century society as profoundly as civil aviation transformed the 20th Century. These mobility breakthroughs will re-establish environmental sustainable centralized aviation, while opening up latent markets for civil distributed sensing and on-demand rural and regional transportation. Of these three transformations, on-demand aviation has the potential to have the largest market and productivity improvement to society. The information system revolution over the past 20 years shows that vehicles lead, and the interconnecting infrastructure to make them more effective follows; that is, unless on-demand aircraft are pioneered, a distributed Air Traffic Control system will likely never be established. There is no single technology long-pole that will enable on-demand vehicle solutions. However, fully digital aircraft that include electric propulsion has the potential to be a multi-disciplinary initiator of solid state technologies that can provide order of magnitude improvements in the ease of use, safety/reliability, community and environmental friendliness, and affordability.

Estimating the residential demand function for natural gas in Seoul with correction for sample selection bias

International Nuclear Information System (INIS)

Yoo, Seung-Hoon; Lim, Hea-Jin; Kwak, Seung-Jun

2009-01-01

Over the last twenty years, the consumption of natural gas in Korea has increased dramatically. This increase has mainly resulted from the rise of consumption in the residential sector. The main objective of the study is to estimate households' demand function for natural gas by applying a sample selection model using data from a survey of households in Seoul. The results show that there exists a selection bias in the sample and that failure to correct for sample selection bias distorts the mean estimate, of the demand for natural gas, downward by 48.1%. In addition, according to the estimation results, the size of the house, the dummy variable for dwelling in an apartment, the dummy variable for having a bed in an inner room, and the household's income all have positive relationships with the demand for natural gas. On the other hand, the size of the family and the price of gas negatively contribute to the demand for natural gas. (author)

PULP DEMAND IN THE INTERNATIONAL MARKET

Directory of Open Access Journals (Sweden)

Edmilson Santos Cruz

2003-01-01

Full Text Available This study aimed at analyzing the international pulp market, taking into account themain exporting countries and importing regions, with the objective of estimating, for each market, theown-price and cross-price elasticity in relation to the demand of the pulp, differentiated for country oforigin. The model considers that imports are differentiated by origin; therefore they are not perfect substitutes. The demand from Europe, North America and the Rest of the World for the pulp from theUnited States,Canada, Sweden, Finland, Portugal and Brazil was inelastic. The Asian demand for thissome pulp was elastic. Europe and the Rest of the World showed negative cross-price elasticity, i. e.,and the imported pulp from other countries are complementary products. North America and Asiashowed positive crow-price elasticity, i. e., they consider the pulp produced in other countries assubstitute products. The net effect of the variation on the price of pulp in a country h, over the amountof pulp that goes to the region i depends on the matching of values related to the elasticity ofsubstitution and the price elasticity of the total demand.

Projection of regional demand for labour force under the terms of industry modernization

Directory of Open Access Journals (Sweden)

Igor Aleksandrovich Bayev

2011-06-01

Full Text Available The article represents the results of research devoted to the problem of demand for labour force projection. The two main priorities of Russian economic development — modernization and innovation — are declared as the factors influencing labour market in a rather intrinsic and specific way. The research of dependence between GDP growth rate per occupied in the most developed countries is conducted and shows the positive influence the innovation process imposes on the demand for labour force. The particular problem is proved to be semi-structured. The selforganisation approach to this problem is proposed and helps to detect that the main shaping process of labour market dynamics is industry modernization. The trend of modernization influence on demand for labour force is revealed and taken under consideration while developing the mathematical model, enabling to predict the demand for labour force with not more than 2% mean absolute percentage error.

Opportunities for Energy Efficiency and Automated Demand Response in Industrial Refrigerated Warehouses in California

Energy Technology Data Exchange (ETDEWEB)

Lekov, Alex; Thompson, Lisa; McKane, Aimee; Rockoff, Alexandra; Piette, Mary Ann

2009-05-11

This report summarizes the Lawrence Berkeley National Laboratory's research to date in characterizing energy efficiency and open automated demand response opportunities for industrial refrigerated warehouses in California. The report describes refrigerated warehouses characteristics, energy use and demand, and control systems. It also discusses energy efficiency and open automated demand response opportunities and provides analysis results from three demand response studies. In addition, several energy efficiency, load management, and demand response case studies are provided for refrigerated warehouses. This study shows that refrigerated warehouses can be excellent candidates for open automated demand response and that facilities which have implemented energy efficiency measures and have centralized control systems are well-suited to shift or shed electrical loads in response to financial incentives, utility bill savings, and/or opportunities to enhance reliability of service. Control technologies installed for energy efficiency and load management purposes can often be adapted for open automated demand response (OpenADR) at little additional cost. These improved controls may prepare facilities to be more receptive to OpenADR due to both increased confidence in the opportunities for controlling energy cost/use and access to the real-time data.

Analysis and design of a Taguchi-Grey based electricity demand predictor for energy management systems

International Nuclear Information System (INIS)

Yao, Albert W.L.; Chi, S.C.

2004-01-01

In order to use electricity efficiently, a demand control management system is one of the effective ways to reduce energy consumption and electric bills. An electricity demand control system is used as a means to monitor and manage the usage of electricity effectively. Moreover, it is a useful tool for avoiding penalties beyond the contracted demand value of electricity with the electric power company. In this project, we developed a Taguchi-Grey based predictor to forecast the demand value of electricity on line. In a Grey prediction, the parameter settings are highly relevant to the accuracy of forecasting. A Taguchi method was employed to optimize the parameter settings for the Grey based electricity demand value predictor. Our experimental results show that the optimal parameter settings of the Grey prediction are α=0.4, five point modeling and three minute sampling time of the data acquisition system. The improved Taguchi-Grey based electricity demand predictor in conjunction with the PC based electricity demand control system is a cost effective and efficient means to manage the usage of electricity

The impact of predicted demand on energy production

Science.gov (United States)

El kafazi, I.; Bannari, R.; Aboutafail, My. O.

2018-05-01

Energy is crucial for human life, a secure and accessible supply of power is essential for the sustainability of societies. Economic development and demographic progression increase energy demand, prompting countries to conduct research and studies on energy demand and production. Although, increasing in energy demand in the future requires a correct determination of the amount of energy supplied. Our article studies the impact of demand on energy production to find the relationship between the two latter and managing properly the production between the different energy sources. Historical data of demand and energy production since 2000 are used. The data are processed by the regression model to study the impact of demand on production. The obtained results indicate that demand has a positive and significant impact on production (high impact). Production is also increasing but at a slower pace. In this work, Morocco is considered as a case study.

Modelling energy demand in the buildings sector within the EU

Energy Technology Data Exchange (ETDEWEB)

O Broin, Eoin

2012-11-01

In the on-going effort within the EU to tackle greenhouse gas emissions and secure future energy supplies, the buildings sector is often referred to as offering a large potential for energy savings. The aim of this thesis is to produce scenarios that highlight the parameters that affect the energy demands and thus potentials for savings of the building sector. Top-down and bottom-up approaches to modelling energy demand in EU buildings are applied in this thesis. The top-down approach uses econometrics to establish the historical contribution of various parameters to energy demands for space and water heating in the residential sectors of four EU countries. The bottom-up approach models the explicit impact of trends in energy efficiency improvement on total energy demand in the EU buildings stock. The two approaches are implemented independently, i.e., the results from the top-down studies do not feed into those from the bottom-up studies or vice versa. The explanatory variables used in the top-down approach are: energy prices; heating degree days, as a proxy for outdoor climate; a linear time trend, as a proxy for technology development; and the lag of energy demand, as a proxy for inertia in the system. In this case, inertia refers to the time it takes to replace space and water heating systems in reaction to price changes. The analysis gives long-term price elasticities of demand as follows: for France, -0.17; for Italy, -0.35; for Sweden, -0.27; and for the UK, -0.35. These results reveal that the price elasticity of demand for space and water heating is inelastic in each of these cases. Nonetheless, scenarios created for the period up to 2050 using these elasticities and an annual price increase of 3 % show that demand can be reduced by more than 1 % per year in France and Sweden and by less than 1 % per year in Italy and the UK. In the bottom-up modelling, varying rates for conversion efficiencies, heating standards for new buildings, end-use efficiency, and

Economic, demographic and social factors of energy demand in Mexican households, 2008-2014

Science.gov (United States)

Perez Pena, Rafael

This research project focuses on estimating the effect of economic, demographic, and social factors in residential energy demand in Mexico from 2008 to 2014. Therefore, it estimates demand equations for electricity, natural gas, liquefied petroleum gas (LPG), coal and natural gas using Mexican household data from 2008 to 2014. It also applies accessibility theory and it estimates energy access indicators using different specifications of demand for LPG in 2014. Sprawl measures, gravity model, and central place theory are the accessibility theory supporting the energy access indicators. Results suggest the greater the household income, the population size, the educational level of the householder, the energy access, and the lower the energy price and the household size, the greater the demand for energy in Mexico from 2008 to 2014. The greater the education, the lower the demand for firewood and coal. LPG and firewood have a monopolistically competitive market structure. Energy access indicators informed by accessibility theory are statistically significant and show the expected sign when applied to LPG in Mexican household in 2014.

Evolution of residential electricity demand by end-use in Quebec 1979-1989: A conditional demand analysis

International Nuclear Information System (INIS)

Lafrance, G.; Perron, D.

1994-01-01

Some of the main conclusions are presented from a temporal analysis of three large-scale electricity demand surveys (1979, 1984, and 1989) for the Quebec residential sector. A regression method called conditional demand analysis was used. The study allows a number of conclusions about certain electricity consumption trends by end-uses from 1979 to 1989 by household type and by vintage category. For example, the results indicate that decreasing electricity consumption between 1979 and 1984 for a typical dwelling equipped with electric space heating was mainly related to a large decline in net heating consumption. Overall, the results suggest that some permanent energy savings have been realized by a typical household equipped with an electric heating system due to improvements in standards and changes in customer behavior. These energy savings were partly offset by increased electricity consumption from the purchase of new appliances and an increase in the demand for hot water. 7 refs., 1 fig., 8 tabs

Economic growth, regional disparities and energy demand in China

International Nuclear Information System (INIS)

Sheng, Yu; Shi, Xunpeng; Zhang, Dandan

2014-01-01

Using the panel data of 27 provinces between 1978 and 2008, we employed a instrumental regression technique to examine the relationship between economic growth, energy demand/production and the related policies in China. The empirical results show that forming a cross-province integrated energy market will in general reduce the response of equilibrium user costs of energy products to their local demand and production, through cross-regional energy transfer (including both energy trade and cross-regional reallocation). In particular, reducing transportation costs and improving marketization level are identified as two important policy instruments to enhance the role of energy market integration. The findings support the argument for a more competitive cross-province energy transfer policies and calls for more developed energy connectivity and associate institutional arrangements within China. These policy implications may also be extended to the East Asia Summit region where energy market integration is being actively promoted. - Highlights: • Development driving energy demand has different impacts on energy prices than others. • EMI will reduce the response of equilibrium energy prices to local demand and production. • Reducing transportation costs and improving marketization level enhance the role of EMI. • More market competition and better physical and institutional connectivity are better. • Policy implications to China may be extended to the East Asia Summit region

Further examination of the temporal stability of alcohol demand.

Science.gov (United States)

Acuff, Samuel F; Murphy, James G

2017-08-01

Demand, or the amount of a substance consumed as a function of price, is a central dependent measure in behavioral economic research and represents the relative valuation of a substance. Although demand is often utilized as an index of substance use severity and is assumed to be relatively stable, recent experimental and clinical research has identified conditions in which demand can be manipulated, such as through craving and stress inductions, and treatment. Our study examines the 1-month reliability of the alcohol purchase task in a sample of heavy drinking college students. We also analyzed reliability in subgroup of individuals whose consumption decreased, increased, or stayed the same over the 1-month period, and in individuals with moderate/severe Alcohol Use Disorder (AUD) vs. those with no/mild AUD. Reliability was moderate in the full sample, high in the group with stable consumption, and did not differ appreciably between AUD groups. Observed indices and indices derived from an exponentiated equation (Koffarnus et al., 2015) were generally comparable, although P max observed had very low reliability. Area under the curve, O max derived, and essential value showed the greatest reliability in the full sample (rs=0.75-0.77). These results provide evidence for the relative stability over time of demand and across AUD groups, particularly in those whose consumption remains stable. Copyright © 2017 Elsevier B.V. All rights reserved.

Sensitivity Analysis Of Financing Demand In Syariah Banking

Directory of Open Access Journals (Sweden)

DR. HJ. ROSYETTI

2017-11-01

Full Text Available This study aims to analyze the Sensitivity of Demand Financing in syariah banking with a focus on the elasticity of financing demand income elasticity and cross elasticity. The type of data used in this study is secondary data quantitative and time series obtained from the publication of BPS BI and OJK. The data analysis technique begins by estimating multiple linear regression equations using the Eviews Application further measuring the sensitivity using elasticity. The research variables consist of revenue gross domestic product and conventional bank interest rate as independent variables and demand for financing as a dependent variable. The results obtained for the results gross domestic product and interest rate of conventional banks simultaneously affect the demand for financing in Islamic banking with a significant level of 5 obtained probability value F statistic amp945 005. Partially revenue share and gross domestic product have a significant effect on demand for financing. While the variable interest rate of conventional banks partially does not have a significant effect on demand for financing in Islamic banking. The ability of the three independent variables to explain the dependent variable of 99.06 the rest of 0.04 influenced by other factors outside this study. The sensitive value of demand for financing in syariah banking during the observation period was 3.94 amp400P 1 so that it can be said that demand for financing in syariah banking is elastic. The elasticity of income demand for financing in syariah banking during the observation period of 3.08 amp400I 1 is categorized as luxuries goods. The cross elasticity value of financing demand in syariah banking during the observation period is 0.52 or positive amp400C 0 it can be categorized that the interest rate of a conventional bank is a substitute of profit sharing.

The CEDSS model of direct domestic energy demand

OpenAIRE

Gotts, Nicholas Mark

2014-01-01

This paper describes the design, implementation and testing of the CEDSS model of direct domestic energy demand, and the first results of its use to produce estimates of future demand under a range of scenarios. CEDSS simulates direct domestic energy demand at within communities of approximately 200 households. The scenarios explored differ in the economic conditions assumed, and policy measures adopted at national level.

Is the available cropland and water enough for food demand? A global perspective of the Land-Water-Food nexus

Science.gov (United States)

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.

Electricity demand forecasting techniques

International Nuclear Information System (INIS)

Gnanalingam, K.

1994-01-01

Electricity demand forecasting plays an important role in power generation. The two areas of data that have to be forecasted in a power system are peak demand which determines the capacity (MW) of the plant required and annual energy demand (GWH). Methods used in electricity demand forecasting include time trend analysis and econometric methods. In forecasting, identification of manpower demand, identification of key planning factors, decision on planning horizon, differentiation between prediction and projection (i.e. development of different scenarios) and choosing from different forecasting techniques are important

On the path independence conditions for discrete-continuous demand

DEFF Research Database (Denmark)

Batley, Richard; Ibáñez Rivas, Juan Nicolás

2013-01-01

We consider the manner in which the well-established path independence conditions apply to Small and Rosen's (1981) problem of discrete-continuous demand, focussing especially upon the restricted case of discrete choice (probabilistic) demand. We note that the consumer surplus measure promoted...... by Small and Rosen, which is specific to the probabilistic demand, imposes path independence to price changes a priori. We find that path independence to income changes can further be imposed provided a numeraire good is available in the consumption set. We show that, for practical purposes, Mc...

On the demand for prescription drugs: heterogeneity in price responses.

Science.gov (United States)

Skipper, Niels

2013-07-01

This paper estimates the price elasticity of demand for prescription drugs using an exogenous shift in consumer co-payment caused by a reform in the Danish subsidy scheme for the general public. Using purchasing records for the entire Danish population, I show that the average price response for the most commonly used drug yields demand elasticities in the range of -0.36 to -0.5. The reform is shown to affect women, the elderly, and immigrants the most. Furthermore, this paper shows significant heterogeneity in the price response over different types of antibiotics, suggesting that the price elasticity of demand varies considerably even across relatively similar drugs. Copyright © 2012 John Wiley & Sons, Ltd.

USING ALMOST IDEAL DEMAND SYSTEM TO ANALYZE DEMAND FOR SHRIMP IN US FOOD MARKET

Directory of Open Access Journals (Sweden)

Xia “Vivian” Zhou

2015-07-01

Full Text Available This paper analyzes the demand for shrimp along with beef, pork, and chicken in the US food market, which contributes much to predicting supply strategies, consumer preferences and policy making. It focuses on the own and cross elasticity relationship between the expenditure share, price, and expenditure changes. An Almost Ideal Demand System (AIDs model and two alternative specifications (both nonlinear AIDs and LA-AIDs are used to estimate a system of expenditure share equations for ocean shrimp, penaeid shrimp, beef, pork, and chicken. Empirical results from nonlinear AIDs model is compared with those from LA-AIDs model. There are quite a few inconsistency between nonlinear and LA results. Results from nonlinear are more expected and more complied with microeconomic theory than those from LA. Also, results indicated that some insignificant slope coefficients and inappropriate signs of them did not comply with microeconomic theory. This could be caused by heteroscedasticity, autocorrelation, a limitation in the data used, or shrimp is a quite different commodity.

Projected Demand and Potential Impacts to the National Airspace System of Autonomous, Electric, On-Demand Small Aircraft

Science.gov (United States)

Smith, Jeremy C.; Viken, Jeffrey K.; Guerreiro, Nelson M.; Dollyhigh, Samuel M.; Fenbert, James W.; Hartman, Christopher L.; Kwa, Teck-Seng; Moore, Mark D.

2012-01-01

Electric propulsion and autonomy are technology frontiers that offer tremendous potential to achieve low operating costs for small-aircraft. Such technologies enable simple and safe to operate vehicles that could dramatically improve regional transportation accessibility and speed through point-to-point operations. This analysis develops an understanding of the potential traffic volume and National Airspace System (NAS) capacity for small on-demand aircraft operations. Future demand projections use the Transportation Systems Analysis Model (TSAM), a tool suite developed by NASA and the Transportation Laboratory of Virginia Polytechnic Institute. Demand projections from TSAM contain the mode of travel, number of trips and geographic distribution of trips. For this study, the mode of travel can be commercial aircraft, automobile and on-demand aircraft. NASA's Airspace Concept Evaluation System (ACES) is used to assess NAS impact. This simulation takes a schedule that includes all flights: commercial passenger and cargo; conventional General Aviation and on-demand small aircraft, and operates them in the simulated NAS. The results of this analysis projects very large trip numbers for an on-demand air transportation system competitive with automobiles in cost per passenger mile. The significance is this type of air transportation can enhance mobility for communities that currently lack access to commercial air transportation. Another significant finding is that the large numbers of operations can have an impact on the current NAS infrastructure used by commercial airlines and cargo operators, even if on-demand traffic does not use the 28 airports in the Continental U.S. designated as large hubs by the FAA. Some smaller airports will experience greater demand than their current capacity allows and will require upgrading. In addition, in future years as demand grows and vehicle performance improves other non-conventional facilities such as short runways incorporated into

Increasing access to institutional deliveries using demand and supply side incentives: early results from a quasi-experimental study

Directory of Open Access Journals (Sweden)

Serwadda David

2011-03-01

Full Text Available Abstract Background Geographical inaccessibility, lack of transport, and financial burdens are some of the demand side constraints to maternal health services in Uganda, while supply side problems include poor quality services related to unmotivated health workers and inadequate supplies. Most public health interventions in Uganda have addressed only selected supply side issues, and universities have focused their efforts on providing maternal services at tertiary hospitals. To demonstrate how reforms at Makerere University College of Health Sciences (MakCHS can lead to making systemic changes that can improve maternal health services, a demand and supply side strategy was developed by working with local communities and national stakeholders. Methods This quasi-experimental trial is conducted in two districts in Eastern Uganda. The supply side component includes health worker refresher training and additions of minimal drugs and supplies, whereas the demand side component involves vouchers given to pregnant women for motorcycle transport and the payment to service providers for antenatal, delivery, and postnatal care. The trial is ongoing, but early analysis from routine health information systems on the number of services used is presented. Results Motorcyclists in the community organized themselves to accept vouchers in exchange for transport for antenatal care, deliveries and postnatal care, and have become actively involved in ensuring that women obtain care. Increases in antenatal, delivery, and postnatal care were demonstrated, with the number of safe deliveries in the intervention area immediately jumping from Conclusions Transport and service vouchers appear to be a viable strategy for rapidly increasing maternal care. MakCHS can design strategies together with stakeholders using a learning-by-doing approach to take advantage of community resources.

The future prospects of supply and demand for urologists in Korea.

Science.gov (United States)

Oh, Youngho

2017-11-01

The purpose of this study was to forecast the future supply and demand for urologists and to discuss the possible policy implications. A demographic utilization-based model was used to calculate the total urologist requirements for Korea. Utilization rates for ambulatory and inpatient genitourinary specialty services were estimated according to age, sex, and insurance status. These rates were used to estimate genitourinary specialty-specific total service utilization expressed in patient care minutes for future populations and converted to genitourinary physician requirements by applying per-genitourinary-physician productivity estimates. An in-and-out movement model for urologist supply was used. Depending on assumptions about data at each step in the method, the supply of urologic surgeons is expected to exceed the demand by 2025 under the current enrollment rate of specialists (43.5% in 2012) when comparing the results of the projections under demand scenarios 3 and 4. However, if the current enrollment rate persists, the imbalance in supply and demand will be not severe by 2030. The degree of imbalance can be alleviated by 2030 by maintaining the current occupancy rate of urologic residents of 43.5%. This study shows that the number of residents needs to be reduced according to the supply and demand for urologic surgeons. Moreover, a policy should be established to maintain the current occupancy rate of residents. The factors affecting the supply and demand of urologic surgeons are complicated. Thus, comprehensive policies encompassing these factors should be established with appropriate solutions.

PREDICTION OF DEMAND FOR PRIMARY BOND OFFERINGS USING ARTIFICIAL NEURAL NETWORKS

Directory of Open Access Journals (Sweden)

Michal Tkac

2014-12-01

Full Text Available Purpose: Primary bond markets represent an interesting investment opportunity not only for banks, insurance companies, and other institutional investors, but also for individuals looking for capital gains. Since offered securities vary in terms of their rating, industrial classification, coupon, or maturity, demand of buyers for particular offerings often overcomes issued volume and price of given bond on secondary market consequently rises. Investors might be regarded as consumers purchasing required service according to their specific preferences at desired price. This paper aims at analysis of demand for bonds on primary market using artificial neural networks.Design/methodology: We design a multilayered feedforward neural network trained by Levenberg-Marquardt algorithm in order to estimate demand for individual bonds based on parameters of particular offerings. Outcomes obtained by artificial neural network are compared with conventional econometric methods.Findings: Our results indicate that artificial neural network significantly outperformed standard econometric techniques and on examined sample of primary bond offerings achieved considerably better performance in terms of prediction accuracy and mean squared error.Originality: We show that proposed neural network is able to successfully predict demand for primary obligation offerings based on their specifications. Moreover, we identify relevant parameters of issues which are able to considerably affect total demand for given security.  Our findings might not only help investors to detect marketable securities, but also enable issuing entities to increase demand for their bonds in order to decrease their offering price. 

International Oil Supplies and Demands

International Nuclear Information System (INIS)

1991-09-01

The eleventh Energy Modeling Forum (EMF) working group met four times over the 1989--90 period to compare alternative perspectives on international oil supplies and demands through 2010 and to discuss how alternative supply and demand trends influence the world's dependence upon Middle Eastern oil. Proprietors of eleven economic models of the world oil market used their respective models to simulate a dozen scenarios using standardized assumptions. From its inception, the study was not designed to focus on the short-run impacts of disruptions on oil markets. Nor did the working group attempt to provide a forecast or just a single view of the likely future path for oil prices. The model results guided the group's thinking about many important longer-run market relationships and helped to identify differences of opinion about future oil supplies, demands, and dependence

International Oil Supplies and Demands

International Nuclear Information System (INIS)

1992-04-01

The eleventh Energy Modeling Forum (EMF) working group met four times over the 1989--1990 period to compare alternative perspectives on international oil supplies and demands through 2010 and to discuss how alternative supply and demand trends influence the world's dependence upon Middle Eastern oil. Proprietors of eleven economic models of the world oil market used their respective models to simulate a dozen scenarios using standardized assumptions. From its inception, the study was not designed to focus on the short-run impacts of disruptions on oil markets. Nor did the working group attempt to provide a forecast or just a single view of the likely future path for oil prices. The model results guided the group's thinking about many important longer-run market relationships and helped to identify differences of opinion about future oil supplies, demands, and dependence

International Oil Supplies and Demands

Energy Technology Data Exchange (ETDEWEB)

1991-09-01

The eleventh Energy Modeling Forum (EMF) working group met four times over the 1989--90 period to compare alternative perspectives on international oil supplies and demands through 2010 and to discuss how alternative supply and demand trends influence the world's dependence upon Middle Eastern oil. Proprietors of eleven economic models of the world oil market used their respective models to simulate a dozen scenarios using standardized assumptions. From its inception, the study was not designed to focus on the short-run impacts of disruptions on oil markets. Nor did the working group attempt to provide a forecast or just a single view of the likely future path for oil prices. The model results guided the group's thinking about many important longer-run market relationships and helped to identify differences of opinion about future oil supplies, demands, and dependence.

International Oil Supplies and Demands

Energy Technology Data Exchange (ETDEWEB)

1992-04-01

The eleventh Energy Modeling Forum (EMF) working group met four times over the 1989--1990 period to compare alternative perspectives on international oil supplies and demands through 2010 and to discuss how alternative supply and demand trends influence the world's dependence upon Middle Eastern oil. Proprietors of eleven economic models of the world oil market used their respective models to simulate a dozen scenarios using standardized assumptions. From its inception, the study was not designed to focus on the short-run impacts of disruptions on oil markets. Nor did the working group attempt to provide a forecast or just a single view of the likely future path for oil prices. The model results guided the group's thinking about many important longer-run market relationships and helped to identify differences of opinion about future oil supplies, demands, and dependence.

Forecasting domestic water demand in the Haihe river basin under changing environment

Directory of Open Access Journals (Sweden)

X.-J. Wang

2018-02-01

Full Text Available A statistical model has been developed for forecasting domestic water demand in Haihe river basin of China due to population growth, technological advances and climate change. Historical records of domestic water use, climate, population and urbanization are used for the development of model. An ensemble of seven general circulation models (GCMs namely, BCC-CSM1-1, BNU-ESM, CNRM-CM5, GISS-E2-R, MIROC-ESM, PI-ESM-LR, MRI-CGCM3 were used for the projection of climate and the changes in water demand in the Haihe River basin under Representative Concentration Pathways (RCPs 4.5. The results showed that domestic water demand in different sub-basins of the Haihe river basin will gradually increase due to continuous increase of population and rise in temperature. It is projected to increase maximum 136.22  ×  108 m3 by GCM BNU-ESM and the minimum 107.25  ×  108 m3 by CNRM-CM5 in 2030. In spite of uncertainty in projection, it can be remarked that climate change and population growth would cause increase in water demand and consequently, reduce the gap between water supply and demand, which eventually aggravate the condition of existing water stress in the basin. Water demand management should be emphasized for adaptation to ever increasing water demand and mitigation of the impacts of environmental changes.

Short- and long-run demand for energy in Mexico: a cointegration approach

International Nuclear Information System (INIS)

Galindo, L.M.

2005-01-01

The objective of this paper is to estimate the demands for the different types of energy consumption for the Mexican economy over the period 1965-2001. These demands are modeled as a function of output and the own real price. The Johansen (J. Econ. Dynamics Control 12 (1988) 231) procedure and the likelihood ratio tests indicate the existence of long-run and stable relationships between each type of energy demand and income with the exception of the industrial sector where the cointegrating vector also includes the relative prices. The weak exogeneity tests indicate that energy consumption and income do not reject the null hypothesis of weak exogeneity when relative prices are weak exogenous. The final econometric models show that relative prices in the short run are relevant in all cases, with the exception of the residential sector. These results indicate that in Mexico the demand for energy is fundamentally driven by income and that the effect of the relative prices is basically concentrated on the short run with the exception of the industrial sector, which also shows a long-term price impact. The strong dependence of energy consumption with respect to income and the price inelastic response indicates that it is necessary to introduce strong measures to decouple energy consumption from output in order to obtain sustainable economic growth in Mexico

Impact of men's perception on family planning demand and uptake in Nigeria.

Science.gov (United States)

Adanikin, Abiodun Idowu; McGrath, Nuala; Padmadas, Sabu S

2017-12-01

Evidence from the last three Demographic and Health Surveys (DHS) in Nigeria shows slow progress in family planning (FP) uptake, despite programmatic interventions. While socioeconomic and religious barriers continue to exist, psychosocial factors such as negative contraceptive perceptions by male partners may influence both spousal FP demand and use. Therefore, this research investigates the influence of male partners' contraceptive perceptions on spousal FP demand and use. We analysed the couple dataset from the 2013 Nigeria DHS. One in five men held the perception that contraceptive use is women's business whereas two in five men reported that women who use family planning may become promiscuous, especially older men, those with no formal education, Muslims and residents in rural areas and northern region. Results from regression models, controlling for relevant sociodemographic characteristics, show that men's perception that contraception is women's business did not significantly influence FP demand. However, their fear that women who use family planning may become promiscuous was associated with lower odds of FP demand (AOR: 0.86; 95% CI: 0.76-0.97) and increased the odds of traditional methods use (AOR: 1.34; 95% CI: 1.01-1.79). The findings direct the need to adopt targeted approach focusing on couples, and reorient policy and program efforts for FP counselling and behavioural changes in men. Copyright © 2017 Elsevier B.V. All rights reserved.

Optimized maritime emergency resource allocation under dynamic demand.

Directory of Open Access Journals (Sweden)

Wenfen Zhang

Full Text Available Emergency resource is important for people evacuation and property rescue when accident occurs. The relief efforts could be promoted by a reasonable emergency resource allocation schedule in advance. As the marine environment is complicated and changeful, the place, type, severity of maritime accident is uncertain and stochastic, bringing about dynamic demand of emergency resource. Considering dynamic demand, how to make a reasonable emergency resource allocation schedule is challenging. The key problem is to determine the optimal stock of emergency resource for supplier centers to improve relief efforts. This paper studies the dynamic demand, and which is defined as a set. Then a maritime emergency resource allocation model with uncertain data is presented. Afterwards, a robust approach is developed and used to make sure that the resource allocation schedule performs well with dynamic demand. Finally, a case study shows that the proposed methodology is feasible in maritime emergency resource allocation. The findings could help emergency manager to schedule the emergency resource allocation more flexibly in terms of dynamic demand.

Nurses' exhaustion: the role of flow at work between job demands and job resources.

Science.gov (United States)

Zito, Margherita; Cortese, Claudio G; Colombo, Lara

2016-01-01

In the light of the job demands-resources model, this study aimed to detect the mediating role of flow at work between job demands and job resources on one side, and exhaustion on the other. In a historical period where it is necessary to reduce the abandonment of nursing profession, flow is a useful tool to investigate the factors that can promote work motivation and prevent psychological distress. A cross-sectional study was conducted in a hospital, and 279 nurses completed a questionnaire. Analyses conducted are descriptive statistics, alphas, correlations and a structural equations model that considers the mediating role of flow at work. Findings show both the central role of job resources in determining flow at work, and the mediating role of flow at work in decreasing exhaustion, starting from job resources, and in decreasing the effect of job demands on exhaustion. Moreover, flow at work directly decreases exhaustion. Results show the relevance of containing job demands and provide job resources to promote positive experiences at work. To promote flow at work, organizations should offer specific resources, such as supervisors' support, job autonomy, and psychological support to manage the emotional charge. © 2015 John Wiley & Sons Ltd.

Forecasting fluid milk and cheese demands for the next decade.

Science.gov (United States)

Schmit, T M; Kaiser, H M

2006-12-01

Predictions of future market demands and farm prices for dairy products are important determinants in developing marketing strategies and farm-production planning decisions. The objective of this report was to use current aggregate forecast data, combined with existing econometric models of demand and supply, to forecast retail demands for fluid milk and cheese and the supply and price of farm milk over the next decade. In doing so, we can investigate whether projections of population and consumer food-spending patterns will extend or alter current consumption trends and examine the implications of future generic advertising strategies for dairy products. To conduct the forecast simulations and appropriately allocate the farm milk supply to various uses, we used a partial equilibrium model of the US domestic dairy sector that segmented the industry into retail, wholesale, and farm markets. Model simulation results indicated that declines in retail per capita demand would persist but at a reduced rate from years past and that retail per capita demand for cheese would continue to grow and strengthen over the next decade. These predictions rely on expected changes in the size of populations of various ages, races, and ethnicities and on existing patterns of spending on food at home and away from home. The combined effect of these forecasted changes in demand levels was reflected in annualized growth in the total farm-milk supply that was similar to growth realized during the past few years. Although we expect nominal farm milk prices to increase over the next decade, we expect real prices (relative to assumed growth in feed costs) to remain relatively stable and show no increase until the end of the forecast period. Supplemental industry model simulations also suggested that net losses in producer revenues would result if only nominal levels of generic advertising spending were maintained in forthcoming years. In fact, if real generic advertising expenditures are

Selection of spatial reference frames depends on task's demands

Directory of Open Access Journals (Sweden)

Greeshma Sharma

2016-12-01

Full Text Available Spatial reference frames (SRF are the means of representing spatial relations or locations either in an egocentric coordinate system (centred on navigator or in an allocentric coordinate system (Centred on object. It is necessary to understand when and how spatial representation switches between allocentric and egocentric reference frames in context to spatial tasks. The objective of this study was to explore if the elementary spatial representation does exist, whether it would remain consistent or change under the influence of a task's demand. Also, we explored how the SRF would assist if the environment is enriched with landmarks, having multiple routes for wayfinding. The results showed that the switching of SRF depends not only on the default representation but also on a task's demand. They also demonstrated that participants who were using allocentric representation performed better in the presence of landmarks.

Optimization of Occupancy Based Demand Controlled Ventilation in Residences

DEFF Research Database (Denmark)

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

2011-01-01

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

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

Science.gov (United States)

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

2018-04-01

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

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

NARCIS (Netherlands)

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

2013-01-01

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

Quantitative work demands, emotional demands, and cognitive stress symptoms in surgery nurses.

Science.gov (United States)

Elfering, Achim; Grebner, Simone; Leitner, Monika; Hirschmüller, Anja; Kubosch, Eva Johanna; Baur, Heiner

2017-06-01

In surgery, cognitive stress symptoms, including problems in concentrating, deciding, memorising, and reflecting are risks to patient safety. Recent evidence points to social stressors as antecedents of cognitive stress symptoms in surgery personnel. The current study tests whether cognitive stress symptoms are positively associated with emotional abuse, emotional- and task-related demands and resources in surgery work. Forty-eight surgery nurses from two hospitals filled out the Copenhagen Psychosocial Questionnaire in its German version. Task-related and emotional demands were positively related to cognitive stress symptoms. In a stepwise, multiple, linear regression of cognitive stress symptoms on task-related and emotional demands, emotional abuse and emotional demands were unique predictors (p emotional abuse, emotional demands, and, therefore, communication and cooperation team climate in surgery personnel.

A Growing Demand for Monitoring and Evaluation in Africa

Directory of Open Access Journals (Sweden)

Stephen Porter

2013-09-01

Full Text Available When decision-makers want to use evidence from monitoring and evaluation (M&E systems to assist them in making choices, there is a demand for M&E. When there is great capacity to supply M&E information, but low capacity to demand quality evidence, there is a mismatch between supply and demand. In this context, as Picciotto (2009 observed, ‘monitoring masquerades as evaluation’. This article applies this observation, using six case studies of African M&E systems, by asking: What evidence is there that African governments are developing stronger endogenous demand for evidence generated from M&E systems? The argument presented here is that demand for evidence is increasing, leading to further development of M&E systems, with monitoring being dominant. As part of this dominance there are attempts to align monitoring systems to emerging local demand, whilst donor demands are still important in several countries. There is also evidence of increasing demand through government-led evaluation systems in South Africa, Uganda and Benin. One of the main issues that this article notes is that the M&E systems are not yet conceptualised within a reform effort to introduce a comprehensive results-based orientation to the public services of these countries. Results concepts are not yet consistently applied throughout the M&E systems in the case countries. In addition, the results-based notions that are applied appear to be generating perverse incentives that reinforce upward compliance and contrôle to the detriment of more developmental uses of M&E evidence.

An Analysis on change of household electricity demand pattern

Energy Technology Data Exchange (ETDEWEB)

Na, In Gang [Korea Energy Economics Institute, Euiwang (Korea)

1999-01-01

The object of this study is to analyze the behavioral pattern change of household electricity demand. Through the cross section analysis using materials from the energy total research report, the change in income elasticity of household electricity demand was studied. In this study, two methodologies were used. Firstly, it was shown that the effect of an income variable was very significant with a positive value in simultaneous equations model using exponential equations of electrical appliances holding. Cross section income effect showed a various distribution according to the season or income level. Overall, it was calculated at 0.111 when the appliances are fixed and 0.432 when even appliances are changed. Secondly, using a choice convenient correction model, it is resulted that lambda, the choice convenient correction factor, has a positive value and is statistically significant. In 1996, income elasticity of electricity demand for households with air-conditioning was 0.305 and for households without air-conditioning was 0.172. Income elasticity of households with air-conditioning is increasing as time goes by while income elasticity of households without air-conditioning is decreasing. (author). 32 refs., 35 tabs.

Main Determinants of Supplementary Health Insurance Demand: (Case of Iran)

Science.gov (United States)

Motlagh, Soraya Nouraei; Gorji, Hassan Abolghasem; Mahdavi, Ghadir; Ghaderi, Hossein

2015-01-01

Introduction: In the majority of developing countries, the volume of medical insurance services, provided by social insurance organizations is inadequate. Thus, supplementary medical insurance is proposed as a means to address inadequacy of medical insurance. Accordingly, in this article, we attempted to provide the context for expansion of this important branch of insurance through identification of essential factors affecting demand for supplementary medical insurance. Method: In this study, two methods were used to identify essential factors affecting choice of supplementary medical insurance including Classification and Regression Trees (CART) and Bayesian logit. To this end, Excel® software was used to refine data and R® software for estimation. The present study was conducted during 2012, covering all provinces in Iran. Sample size included 18,541 urban households, selected by Statistical Center of Iran using 3-stage cluster sampling approach. In this study, all data required were collected from the Statistical Center of Iran. Results: In 2012, an overall 8.04% of the Iranian population benefited from supplementary medical insurance. Demand for supplementary insurance is a concave function of age of the household head, and peaks in middle-age when savings and income are highest. The present study results showed greater likelihood of demand for supplementary medical insurance in households with better economic status, higher educated heads, female heads, and smaller households with greater expected medical expenses, and household income is the most important factor affecting demand for supplementary medical insurance. Conclusion: Since demand for supplementary medical insurance is hugely influenced by households’ economic status, policy-makers in the health sector should devise measures to improve households’ economic or financial access to supplementary insurance services, by identifying households in the lower economic deciles, and increasing their

Opportunities for Automated Demand Response in California Agricultural Irrigation

Energy Technology Data Exchange (ETDEWEB)

Olsen, Daniel [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Aghajanzadeh, Arian [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); McKane, Aimee [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2015-08-01

Pumping water for agricultural irrigation represents a significant share of California’s annual electricity use and peak demand. It also represents a large source of potential flexibility, as farms possess a form of storage in their wetted soil. By carefully modifying their irrigation schedules, growers can participate in demand response without adverse effects on their crops. This report describes the potential for participation in demand response and automated demand response by agricultural irrigators in California, as well as barriers to widespread participation. The report first describes the magnitude, timing, location, purpose, and manner of energy use in California. Typical on-­farm controls are discussed, as well as common impediments to participation in demand response and automated demand response programs. Case studies of demand response programs in California and across the country are reviewed, and their results along with overall California demand estimates are used to estimate statewide demand response potential. Finally, recommendations are made for future research that can enhance the understanding of demand response potential in this industry.

Reducing Energy Demand Using Wheel-Individual Electric Drives to Substitute EPS-Systems

Directory of Open Access Journals (Sweden)

Jürgen Römer

2018-01-01

Full Text Available The energy demand of vehicles is influenced, not only by the drive systems, but also by a number of add-on systems. Electric vehicles must satisfy this energy demand completely from the battery. Hence, the use of power steering systems directly result in a range reduction. The “e2-Lenk” joint project funded by the German Federal Ministry of Education and Research (BMBF involves a novel steering concept for electric vehicles to integrate the function of steering assistance into the drive-train. Specific distribution of driving torque at the steered axle allows the steering wheel torque to be influenced to support the steering force. This provides a potential for complete substitution of conventional power steering systems and reduces the vehicle’s energy demand. This paper shows the potential of wheel-individual drives influencing the driver’s steering torque using a control technique based on classical EPS control plans. Compared to conventional power-assisted steering systems, a reduced energy demand becomes evident over a wide range of operating conditions.

Employer Demand for Welfare Recipients by Race. Discussion Paper.

Science.gov (United States)

Holzer, Harry J.; Stoll, Michael A.

This paper uses new survey data on employers in four large metropolitan areas to examine the determinants of employer demand for welfare recipients. Data come from a telephone survey of approximately 750 establishments. Results suggest a high level of demand for welfare recipients, although such demand appears fairly sensitive to business cycle…

Simple future weather files for estimating heating and cooling demand

DEFF Research Database (Denmark)

Cox, Rimante Andrasiunaite; Drews, Martin; Rode, Carsten

2015-01-01

useful estimates of future energy demand of a building. Experimental results based on both the degree-day method and dynamic simulations suggest that this is indeed the case. Specifically, heating demand estimates were found to be within a few per cent of one another, while estimates of cooling demand...... were slightly more varied. This variation was primarily due to the very few hours of cooling that were required in the region examined. Errors were found to be most likely when the air temperatures were close to the heating or cooling balance points, where the energy demand was modest and even...... relatively large errors might thus result in only modest absolute errors in energy demand....

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

Directory of Open Access Journals (Sweden)

María José Montero-Simó

2013-01-01

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

Optimal Ordering and Pricing Policies for Seasonal Products: Impacts of Demand Uncertainty and Capital Constraint

Directory of Open Access Journals (Sweden)

Jinzhao Shi

2016-01-01

Full Text Available With a stochastic price-dependent market demand, this paper investigates how demand uncertainty and capital constraint affect retailer’s integrated ordering and pricing policies towards seasonal products. The retailer with capital constraint is normalized to be with zero capital endowment while it can be financed by an external bank. The problems are studied under a low and high demand uncertainty scenario, respectively. Results show that when demand uncertainty level is relatively low, the retailer faced with demand uncertainty always sets a lower price than the riskless one, while its order quantity may be smaller or larger than the riskless retailer’s which depends on the level of market size. When adding a capital constraint, the retailer will strictly prefer a higher price but smaller quantity policy. However, in a high demand uncertainty scenario, the impacts are more intricate. The retailer faced with demand uncertainty will always order a larger quantity than the riskless one if demand uncertainty level is high enough (above a critical value, while the capital-constrained retailer is likely to set a lower price than the well-funded one when demand uncertainty level falls within a specific interval. Therefore, it can be further concluded that the impact of capital constraint on the retailer’s pricing decision can be influenced by different demand uncertainty levels.

Negative autoregulation matches production and demand in synthetic transcriptional networks.

Science.gov (United States)

Franco, Elisa; Giordano, Giulia; Forsberg, Per-Ola; Murray, Richard M

2014-08-15

We propose a negative feedback architecture that regulates activity of artificial genes, or "genelets", to meet their output downstream demand, achieving robustness with respect to uncertain open-loop output production rates. In particular, we consider the case where the outputs of two genelets interact to form a single assembled product. We show with analysis and experiments that negative autoregulation matches the production and demand of the outputs: the magnitude of the regulatory signal is proportional to the "error" between the circuit output concentration and its actual demand. This two-device system is experimentally implemented using in vitro transcriptional networks, where reactions are systematically designed by optimizing nucleic acid sequences with publicly available software packages. We build a predictive ordinary differential equation (ODE) model that captures the dynamics of the system and can be used to numerically assess the scalability of this architecture to larger sets of interconnected genes. Finally, with numerical simulations we contrast our negative autoregulation scheme with a cross-activation architecture, which is less scalable and results in slower response times.

Sustainability Analysis and Market Demand Estimation in the Retail Industry through a Convolutional Neural Network

Directory of Open Access Journals (Sweden)

Luyao Wang

2018-05-01

Full Text Available The Chinese retail industry is expected to grow dramatically over the next few years, owing to the rapid increase in purchasing power of Chinese consumers. Retail managers should analyze the market demands and avoid dull sales to promote the sustainable development of the retail industry. Economic sustainability in the retail industry, which refers to a suitable return of investment, requires the implementation of precise product allocation strategies in different regions. This study proposed a hybrid model to evaluate economic sustainability in the preparation of goods of retail shops on the basis of market demand evaluation. Through a grid-based convolutional neural network, a regression model was first established to model the relationship between consumer distribution and the potential market demand. Then, another model was proposed to evaluate the sustainability among regions based on their supply-demand analysis. An experiment was conducted based on the actual sales data of retail shops in Guiyang, China. Results showed an immense diversity of sustainability in the entire city and three classes of regions were distinguished, namely, high, moderate, and limited. Our model was proven to be effective in the sustainability evaluation of supply and demand in the retail industry after validation showed that its accuracy reached 92.8%.

Road infrastructure and demand induction

DEFF Research Database (Denmark)

Nielsen, Thomas Alexander Sick; Hovgesen, Henrik Harder; Lahrmann, Harry

2006-01-01

a long screenline is used to measure the development in aggregate demand in selected corridors. The paper analyses demand induction by establishing time series of aggregate demand that is compared with the national traffic index. Significant trend breaks in the association between aggregate demand...... in the corridors and the national index, following the opening of motorways or bridges, indicates demand induction by infrastructure expansion in a number of instances. Lack of significant trend breaks following opening year is found in peripheral areas where major population centres are missing. This indicates...... the necessity of some latent demand within suitable travel range for new infrastructure elements to produce significant amounts of induced demand. Estimates of demand induction as a percentage of the realised demand five years after opening are between 10% and 67% for new motorway sections depending...

Analysis of Japanese energy demand structure based on the interindustry-relations table

International Nuclear Information System (INIS)

Kanai, Akira; Kashihara, Toshinori

1990-01-01

Matching of energy-supply system and demand system is very important in dealing with the energy problem. Especially the energy-demand system is important for determing the quantity and quality of the energy demand. The energy demand is created by activities of industry and human life. The best materials which describe these activity conditions is the interindustry-relations table. Authors rely on this table as the basic data for assuming the energy demand analysis of energy system. The defect of this table is that an industrial classification differs in publishing years. So the table is lacking in the time sequential consistency. Therefore we discuss the method to improve the defect in consistency. In addition, this report analyses the energy demand structure in Japan according to the improved method. The research is done by the following procedure, 1. The unified common sector data is made so that an industrial classification in the interindustry-relations tables become common. 2. The quantity of input energy in each section is extracted from the tables. 3. The input energy is converted into the characteristic indicator and the calorific indicator. 4. The section is united using the common sector data. 5. The result is shown in table or graph. 6. The energy demand structure is analyzed based on the tables and the graphs. This interindustry-relations table is offered by request in the form of the magnetic tape. All the data is processed by computer due to the abundant amount of data. This report shows the idea how to process the fable instead of displaying the details. In addition, the problem in the analysis of the table is pointed out as results of the analysis. This report describes the feature of 23-sections classification in analysis of the energy demand structure. This report offers a basic data to make energy scenario to the energy system analysists. (J.P.N.)

Forecasting the natural gas demand in China using a self-adapting intelligent grey model

International Nuclear Information System (INIS)

Zeng, Bo; Li, Chuan

2016-01-01

Reasonably forecasting demands of natural gas in China is of significance as it could aid Chinese government in formulating energy policies and adjusting industrial structures. To this end, a self-adapting intelligent grey prediction model is proposed in this paper. Compared with conventional grey models which have the inherent drawbacks of fixed structure and poor adaptability, the proposed new model can automatically optimize model parameters according to the real data characteristics of modeling sequence. In this study, the proposed new model, discrete grey model, even difference grey model and classical grey model were employed, respectively, to simulate China's natural gas demands during 2002–2010 and forecast demands during 2011–2014. The results show the new model has the best simulative and predictive precision. Finally, the new model is used to forecast China's natural gas demand during 2015–2020. The forecast shows the demand will grow rapidly over the next six years. Therefore, in order to maintain the balance between the supplies and the demands for the natural gas in the future, Chinese government needs to take some measures, such as importing huge amounts of natural gas from abroad, increasing the domestic yield, using more alternative energy, and reducing the industrial reliance on natural gas. - Highlights: • A self-adapting intelligent grey prediction model (SIGM) is proposed in this paper. • The SIGM has the advantage of working with exponential functions and linear functions. • The SIGM solves the drawbacks of fixed structure and poor adaptability of grey models. • The demand of natural gas in China is successfully forecasted using the SIGM model. • The study findings can help Chinese government reasonably formulate energy policies.

Extending the bidding format to promote demand response

International Nuclear Information System (INIS)

Liu, Yanchao; Holzer, Jesse T.; Ferris, Michael C.

2015-01-01

We propose an extended bidding structure to allow more realistic demand characteristics and behaviors to be expressed via flexible bids. In today's ISO-run energy markets, demand bid formats are all separable over time. However, a significant and growing segment of demand can be shifted across time and therefore has no way to bid its true valuation of consumption. We propose additional bid types that allow deferrable, adjustable and storage-type loads to better express their value, and thus elicit demand response in the most natural way – via direct participation in the market. We show that the additional bid types are easily incorporated into the existing market with no technological barrier and that they preserve the market's efficiency and incentive-compatibility properties. Using real market data, we give a numerical demonstration that the extended bid format could substantially increase social welfare, and also present additional insight on storage expansion scenarios. - Highlights: • Three new bid types are proposed to enrich demand-side participation. • Time value of electricity demand can be clearly conveyed to central dispatcher. • The extended format preserves market efficiency and incentive compatibility. • Energy storage is most effective to neutralize price volatility, with a limitation.

Hourly price elasticity pattern of electricity demand in the German day-ahead market

OpenAIRE

Knaut, Andreas; Paulus, Simon

2016-01-01

System security in electricity markets relies crucially on the interaction between demand and supply over time. However, research on electricity markets has been mainly focusing on the supply side arguing that demand is rather inelastic. Assuming perfectly inelastic demand might lead to delusive statements regarding the price formation in electricity markets. In this article we quantify the short-run price elasticity of electricity demand in the German day-ahead market and show that demand is...

Start point to savings - Better load demand analysis in commercial buildings

Energy Technology Data Exchange (ETDEWEB)

Abaravicius, Juozas; Pyrko, Jurek [Lund Univ., Dept of Energy Sciences (Sweden)

2007-07-01

Existing installations and energy systems in most commercial buildings could be used in a more efficient way to provide savings - both in terms of energy and load demand. The key for effective operation is a thorough and detailed analysis of energy use patterns that creates essential baseline for energy savings and the development of demand response (DR) strategies. The knowledge of energy demand variations is still very limited and the use of methods to analyse the load demand is rare. Many utilities have recently installed interval (hourly) metering even for smaller commercial users and households. This is a big step forward; however, experience shows that the data is being used only to a limited extent, mostly for billing purposes only. This paper reports about a study conducted with the objective of developing a detailed load demand analysis for commercial buildings. The study results should provide essential information for the formation and evaluation of future DR and energy efficiency strategies. This study was performed in collaboration with IKEA and E.ON and contributes to an ongoing IKEA energy efficiency programme. Two sample department stores in Sweden were selected and analysed within this project. The demand data analysis covers almost 3 years period, 2004-2006.This study contributes to new knowledge of energy use patterns (load demand) in commercial buildings. It proposes solutions of load-related problems, evaluates energy and load savings potential, identifies and analyses the needs, motives and barriers for participation in DR programmes. The study provides recommendations for ongoing and future efficiency and DR strategies and discusses the potential economic benefits from the DR measures.

An EPQ Model with Increasing Demand and Demand Dependent Production Rate under Trade Credit Financing

Directory of Open Access Journals (Sweden)

Juanjuan QIN

2015-05-01

Full Text Available This paper investigates an EPQ model with the increasing demand and demand dependent production rate involving the trade credit financing policy, which is seldom reported in the literatures. The model considers the manufacturer was offered by the supplier a delayed payment time. It is assumed that the demand is a linear increasing function of the time and the production rate is proportional to the demand. That is, the production rate is also a linear function of time. This study attempts to offer a best policy for the replenishment cycle and the order quantity for the manufacturer to maximum its profit per cycle. First, the inventory model is developed under the above situation. Second, some useful theoretical results have been derived to characterize the optimal solutions for the inventory system. The Algorithm is proposed to obtain the optimal solutions of the manufacturer. Finally, the numerical examples are carried out to illustrate the theorems, and the sensitivity analysis of the optimal solutions with respect to the parameters of the inventory system is performed. Some important management insights are obtained based on the analysis.

An adaptive network-based fuzzy inference system for short-term natural gas demand estimation: Uncertain and complex environments

International Nuclear Information System (INIS)

Azadeh, A.; Asadzadeh, S.M.; Ghanbari, A.

2010-01-01

Accurate short-term natural gas (NG) demand estimation and forecasting is vital for policy and decision-making process in energy sector. Moreover, conventional methods may not provide accurate results. This paper presents an adaptive network-based fuzzy inference system (ANFIS) for estimation of NG demand. Standard input variables are used which are day of the week, demand of the same day in previous year, demand of a day before and demand of 2 days before. The proposed ANFIS approach is equipped with pre-processing and post-processing concepts. Moreover, input data are pre-processed (scaled) and finally output data are post-processed (returned to its original scale). The superiority and applicability of the ANFIS approach is shown for Iranian NG consumption from 22/12/2007 to 30/6/2008. Results show that ANFIS provides more accurate results than artificial neural network (ANN) and conventional time series approach. The results of this study provide policy makers with an appropriate tool to make more accurate predictions on future short-term NG demand. This is because the proposed approach is capable of handling non-linearity, complexity as well as uncertainty that may exist in actual data sets due to erratic responses and measurement errors.

Analysis Of Factors Affecting Demand Red Chili Pepper Capsicum Annum L In Solok And Effort Fulfillment

Directory of Open Access Journals (Sweden)

Zulfitriyana

2015-08-01

Full Text Available Research on the analysis of the factors that influence the demand for red chilli Capsicum annuum L in Solok and compliance efforts implemented in March s.d April 2016. The purpose of this study consisted of 1 analyze the factors affecting the demand for red chili in Solok 2 analyze the elasticity of demand for red chili in Solok 3 know the effort that can be done to meet the demand of red chilli in Solok. To achieve the objectives of the first and second use secondary data for 15 fifteen years and to achieve the objectives the third used primary data. The method used is descriptive analytical method a method that is used to describe phenomena that exist which takes place in the present or past. The variables were observed in this study is the X1 price of red chilli X2 the price of green chili X3 onion prices X4 population X5 income and Y the number of requests red chili which is then analyzed by multiple linear regression elasticity of demand and SWOT. The results of that research addressing the factors that influence the demand for red chili in Solok is the price of red chilli itself the price of green chili as a substitute goods the number of population and income while onion prices affect the amount of red chili demand in Solok. But simultaneously variable X1 red chili prices X2 the price of green chili X3 onion prices X4 population and X5 income strongly influence demand red chili in Solok where the F test results show that F count F table 212.262 3600 with a significance level 0.000 0.010 and the most influential variable is the variable X4 population with the greatest value of beta Coefficients is 1100. Based on analysis of the elasticity of demand is known that red chili pepper is a normal good is inelastic to price elasticity coefficient value amp603p of -0.120. Green chili is substituting goods and shallots are complements of red chili with cross elasticity coefficient amp603px1 and amp603px2 respectively by 0293 and -0.635. While the

The development of demand elasticity model for demand response in the retail market environment

NARCIS (Netherlands)

Babar, M.; Nguyen, P.H.; Kamphuis, I.G.

2015-01-01

In the context of liberalized energy market, increase in distributed generation, storage and demand response has expanded the price elasticity of demand, thus causing the addition of uncertainty to the supply-demand chain of power system. In order to cope with the challenges of demand uncertainty

Function and Content of Maternal Demands: Developmental Significance of Early Demands for Competent Action.

Science.gov (United States)

Kuczynski, Leon; Kochanska, Grazyna

1995-01-01

Examined mothers' demands during mothers' interactions with their 1.5- to 3.5-year olds. Mothers with authoritative child-rearing attitudes emphasized proactive, competence-oriented demands and avoided regulatory control. Maternal demands for competent action predicted fewer behavior problems in their children at age five; maternal demands focused…

On-Demand Telemetry

Data.gov (United States)

National Aeronautics and Space Administration — AFRC has previously investigated the use of Network Based Telemetry. We will be building on that research to enable On-Demand Telemetry. On-Demand Telemetry is a way...

Money Demand in Latvia

OpenAIRE

Ivars Tillers

2004-01-01

The econometric analysis of the demand for broad money in Latvia suggests a stable relationship of money demand. The analysis of parameter exogeneity indicates that the equilibrium adjustment is driven solely by the changes in the amount of money. The demand for money in Latvia is characterised by relatively high income elasticity typical for the economy in a monetary expansion phase. Due to stability, close fit of the money demand function and rapid equilibrium adjustment, broad money aggreg...

Assessing long-term effects of demand response policies in wholesale electricity markets

International Nuclear Information System (INIS)

Cepeda, Mauricio; Saguan, Marcelo

2014-05-01

This paper deals with the practical problems related to long-term issues in electricity markets in the presence of demand response development. Different policies have been implemented around the world aiming to develop demand response potential. Externalities, in particular the CO_2 externality, have been one of the key elements in the debate on the effectiveness of different policies regarding demand response development. Policy makers have several options to deal with this externality. The most direct one is to correct the externality by setting a CO_2 price at a level that corresponds to the cost to society of the corresponding CO_2 emissions. One alternative solution could be to subsidize carbon-free technologies as demand response. In this paper we examine potential long-term impacts of these two policies. We rely on a long-term market simulation model that characterizes expansion decisions in a competitive regime. We test for each policy two different scenarios regarding the possibility of internalization of the CO_2 externality. The results show that differences in development policies affect both investments and social costs in the wholesale electricity market and confirm previous findings that a market-driven development of demand response with the internalization of the CO_2 externality is the most efficient approach. (authors)

Architecture design of reconfigurable accelerators for demanding apllications.

NARCIS (Netherlands)

Jozwiak, L.; Jan, Y.

2010-01-01

This paper focuses on mastering the architecture development of reconfigurable hardware accelerators for highly demanding applications. It presents the results of our analysis of the main issues that have to be addressed when designing accelerators for demanding applications, when using as an

Demand for healthcare in India

Directory of Open Access Journals (Sweden)

Brijesh C. Purohit

2013-03-01

Full Text Available In a developing country like India, allocation of scarce fiscal resources has to be based on a clear understanding of how investments in the heath sector are going to affect demand. Three aspects like overall healthcare demand, consumer decisions to use public and/or private care and role of price/quality influencing poor/rich consumer’s decisions are critical to assessing the equity implications of alternative policies. Our paper addresses these aspects through examining the pattern of healthcare demand in India. Data from the National Family Health Survey are used to model the healthcare choices that individuals make. We consider what these behavioral characteristics imply for public policy. This analysis aims to study disparities between rural and urban areas from all throughout India to five Indian states representing three levels of per capita incomes (all-India average, rich and poor. Results evidence that healthcare demand both in rural and urban areas is a commodity emerging as an essential need. Choices between public or private provider are guided by income and quality variables mainly with regard to public healthcare denoting thus a situation of very limited alternatives in terms of availing private providers. These results emphasize that existing public healthcare facilities do not serve the objective of providing care to the poor in a satisfactory manner in rural areas. Thus, any financing strategy to improve health system and reduce disparities across rich-poor states and rural-urban areas should also take into account not only overcoming inadequacy but also inefficiency in allocation and utilization of healthcare inputs.

Strategies for Demand Response in Commercial Buildings

Energy Technology Data Exchange (ETDEWEB)

Watson, David S.; Kiliccote, Sila; Motegi, Naoya; Piette, Mary Ann

2006-06-20

This paper describes strategies that can be used in commercial buildings to temporarily reduce electric load in response to electric grid emergencies in which supplies are limited or in response to high prices that would be incurred if these strategies were not employed. The demand response strategies discussed herein are based on the results of three years of automated demand response field tests in which 28 commercial facilities with an occupied area totaling over 11 million ft{sup 2} were tested. Although the demand response events in the field tests were initiated remotely and performed automatically, the strategies used could also be initiated by on-site building operators and performed manually, if desired. While energy efficiency measures can be used during normal building operations, demand response measures are transient; they are employed to produce a temporary reduction in demand. Demand response strategies achieve reductions in electric demand by temporarily reducing the level of service in facilities. Heating ventilating and air conditioning (HVAC) and lighting are the systems most commonly adjusted for demand response in commercial buildings. The goal of demand response strategies is to meet the electric shed savings targets while minimizing any negative impacts on the occupants of the buildings or the processes that they perform. Occupant complaints were minimal in the field tests. In some cases, ''reductions'' in service level actually improved occupant comfort or productivity. In other cases, permanent improvements in efficiency were discovered through the planning and implementation of ''temporary'' demand response strategies. The DR strategies that are available to a given facility are based on factors such as the type of HVAC, lighting and energy management and control systems (EMCS) installed at the site.

Demand-Withdraw Patterns in Marital Conflict in the Home.

Science.gov (United States)

Papp, Lauren M; Kouros, Chrystyna D; Cummings, E Mark

2009-06-01

The present study extended laboratory-based findings of demand-withdraw communication into marital conflict in the home and further explored its linkages with spousal depression. U.S. couples (N = 116) provided diary reports of marital conflict and rated depressive symptoms. Hierarchical linear modeling results indicated that husband demand-wife withdraw and wife demand-husband withdraw occurred in the home at equal frequency, and both were more likely to occur when discussing topics that concerned the marital relationship. For both patterns, conflict initiator was positively linked to the demander role. Accounting for marital satisfaction, both demand-withdraw patterns predicted negative emotions and tactics during marital interactions and lower levels of conflict resolution. Spousal depression was linked to increased likelihood of husband demand-wife withdraw.

Supplier-induced demand: re-examining identification and misspecification in cross-sectional analysis.

Science.gov (United States)

Peacock, Stuart J; Richardson, Jeffrey R J

2007-09-01

This paper re-examines criticisms of cross-sectional methods used to test for supplier-induced demand (SID) and re-evaluates the empirical evidence using data from Australian medical services. Cross-sectional studies of SID have been criticised on two grounds. First, and most important, the inclusion of the doctor supply in the demand equation leads to an identification problem. This criticism is shown to be invalid, as the doctor supply variable is stochastic and depends upon a variety of other variables including the desirability of the location. Second, cross-sectional studies of SID fail diagnostic tests and produce artefactual findings due to model misspecification. Contrary to this, the re-evaluation of cross-sectional Australian data indicate that demand equations that do not include the doctor supply are misspecified. Empirical evidence from the re-evaluation of Australian medical services data supports the notion of SID. Demand and supply equations are well specified and have very good explanatory power. The demand equation is identified and the desirability of a location is an important predictor of the doctor supply. Results show an average price elasticity of demand of 0.22 and an average elasticity of demand with respect to the doctor supply of 0.46, with the impact of SID becoming stronger as the doctor supply rises. The conclusion we draw from this paper is that two of the main criticisms of the empirical evidence supporting the SID hypothesis have been inappropriately levelled at the methods used. More importantly, SID provides a satisfactory, and robust, explanation of the empirical data on the demand for medical services in Australia.

ELECTRICITY DEMAND IN A NORTHERN MEXICO METROPOLITAN ECONOMY

Directory of Open Access Journals (Sweden)

Thomas M. Fullerton

2014-10-01

Full Text Available Using an error correction framework, this study analyzes the long- and short-run dynamics of electricity demand in Ciudad Juarez, a large metropolitan economy on Mexico’s northern border. Demand is decomposed into the total number of electricity accounts and electricity usage per customer, each of which is modeled separately. A two-stage least squares approach is used to estimate the per customer electricity demand equations due to the endogeneity of the average price variable. The results indicate sustained growth in population, employment, and income can be expected to exert substantial upward pressure on regional electric power demand. Furthermore, demand is found to be price-inelastic in this metropolitan area, suggesting that rate increases can help raise the revenues necessary to fund expansion of the electrical grid.

Demand grows in N. America as gas supply sources shift

International Nuclear Information System (INIS)

Carson, M.M.

1996-01-01

Growing demand for gas as a power-generation fuel is combining with changing patterns of gas transportation to present North American producers and pipelines with a series of new challenges. Results of a recent Enron study show how natural gas supplies available to US markets continue to shift their center of gravity toward Canadian and western sources. These changes--demand growth paced by electricity generation and supply source relocation--plus extraordinary gas basin price differentials this winter, point to (a) the opportunities for and risks of adding pipeline capacity in the US and Canada, on the one hand, and (b) tough decisions that may need to be made by Gulf of Mexico and Midcontinent area producers, on the other, to compete in an environment of changing economics and infrastructure

Household energy demand. Empirical studies concerning Sweden

Energy Technology Data Exchange (ETDEWEB)

Dargay, J; Lundin, A

1978-06-01

This paper investigates the effects of energy policy on households in Sweden and provides the material necessary for evaluation of current and proposed energy-conservation measures. Emphasis is placed on the impact of enery taxation or price changes on household demand for electricity, heating oil, and gasoline and the consequences of such measures for income distribution. The results of the Swedish studies of household demand for heating oil and gasoline indicate that price changes can have a considerable long run impact on fuel utilization. In the short run, price responsiveness is notably reduced, but it is nevertheless of consequence for energy demand.

Large Field Visualization with Demand-Driven Calculation

Science.gov (United States)

Moran, Patrick J.; Henze, Chris

1999-01-01

We present a system designed for the interactive definition and visualization of fields derived from large data sets: the Demand-Driven Visualizer (DDV). The system allows the user to write arbitrary expressions to define new fields, and then apply a variety of visualization techniques to the result. Expressions can include differential operators and numerous other built-in functions, ail of which are evaluated at specific field locations completely on demand. The payoff of following a demand-driven design philosophy throughout becomes particularly evident when working with large time-series data, where the costs of eager evaluation alternatives can be prohibitive.

THE DEMAND FOR MEAT PRODUCTS IN THE UNITED STATES: AN EMPIRICAL ANALYSIS

OpenAIRE

Olowolayemo, Surajudeen O.; Martin, Neil R., Jr.; Raymond, Jennie E.

1993-01-01

Given the importance of meat consumption, and the proportion of consumers' income spent on meat, this study estimates the demand for eight meat categories using two different functional forms. An inverse almost ideal demand system (IAIDS), and linear double-log price dependent demand models are specified. In most cases, flexibilities obtained from both methods are comparable and show that the demand for meat products is price inflexible. In addition, there are regional as well as seasonal var...

Uranium 2007 resources, production and demand

CERN Document Server

Organisation for Economic Cooperation and Development. Paris

2008-01-01

Based on official information received from 40 countries, Uranium 2007 provides a comprehensive review of world uranium supply and demand as of 1st January 2007, as well as data on global uranium exploration, resources, production and reactor-related requirements. It provides substantive new information from major uranium production centres in Africa, Australia, Central Asia, Eastern Europe and North America. Projections of nuclear generating capacity and reactor-related uranium requirements through 2030 are also featured, along with an analysis of long-term uranium supply and demand issues. It finds that with rising demand and declining inventories, uranium prices have increased dramatically in recent years. As a result, the uranium industry is undergoing a significant revival, bringing to an end a period of over 20 years of underinvestment.

Driving monotonous routes in a train simulator: the effect of task demand on driving performance and subjective experience.

Science.gov (United States)

Dunn, Naomi; Williamson, Ann

2012-01-01

Although monotony is widely recognised as being detrimental to performance, its occurrence and effects are not yet well understood. This is despite the fact that task-related characteristics, such as monotony and low task demand, have been shown to contribute to performance decrements over time. Participants completed one of two simulated train-driving scenarios. Both were highly monotonous and differed only in terms of the level of cognitive demand required (i.e. low demand or high demand). These results highlight the seriously detrimental effects of the combination of monotony and low task demands and clearly show that even a relatively minor increase in cognitive demand can mitigate adverse monotony-related effects on performance for extended periods of time. Monotony is an inherent characteristic of transport industries, including rail, aviation and road transport, which can have adverse impact on safety, reliability and efficiency. This study highlights possible strategies for mitigating these adverse effects. Practitioner Summary: This study provides evidence for the importance of cognitive demand in mitigating monotony-related effects on performance. The results have clear implications for the rapid onset of performance deterioration in low demand monotonous tasks and demonstrate that these detrimental performance effects can be overcome with simple solutions, such as making the task more cognitively engaging.

An integrated vendor-buyer model with stock-dependent demand

DEFF Research Database (Denmark)

Sajadieh, Mohsen S.; Thorstenson, Anders; Akbari Jokar, Mohammad R.

in a display area. The end-customer demand is assumed to be positively dependent on the amount of items shown in the display area. With the proposed model we determine the buyer's optimal shipment quantity and number of shipments, as well as the vendor's optimal production batch. The objective is to maximize...... total supply chain profit. The numerical analysis shows that it is more profitable for the buyer and the vendor to cooperate in situations when the demand is more stock-dependent. The analysis also shows the effect of double marginalization in this integrated vendor-buyer model....

An integrated vendor-buyer model with stock-dependent demand

DEFF Research Database (Denmark)

Sajadieh, Mohsen S.; Thorstenson, Anders; Akbari Jokar, Mohammad R.

2010-01-01

We develop an integrated vendor-buyer model for a two-stage supply chain. The vendor manufactures the product and delivers it in a number of equal-sized batches to the buyer. The items delivered are presented to the end customers in a display area. Demand is assumed to be positively dependent...... on the amount of items displayed. The objective is to maximize total supply chain profit. The numerical analysis shows that buyer-vendor coordination is more profitable in situations when demand is more stock dependent. It also shows that the effect of double marginalization provides a link between the non...

An Integrated Vendor-Buyer Model with Stock-Dependent Demand

DEFF Research Database (Denmark)

Thorstenson, Anders; Sajadieh, Mohsen S.; Akbari Jokar, Mohammad R.

2009-01-01

in the buyer's warehouse. The demand is assumed to be positively dependent on the amount of items shown in the display area. The proposed model determines the buyer's optimal shipment quantity and number of shipments, as well as the vendor's optimal production batch. The objective is to maximize total supply......-chain profit. The numerical analysis shows that as long as the maximum display area is not used, it is more valuable for the buyer and the vendor to cooperate in situations when the demand is more stock- dependent. It also shows the effect of double marginalization in this integrated vendor-buyer model....

Deriving local demand for stumpage from estimates of regional supply and demand.

Science.gov (United States)

Kent P. Connaughton; Gerard A. Majerus; David H. Jackson

1989-01-01

The local (Forest-level or local-area) demand for stumpage can be derived from estimates of regional supply and demand. The derivation of local demand is justified when the local timber economy is similar to the regional timber economy; a simple regression of local on nonlocal prices can be used as an empirical test of similarity between local and regional economies....

Energy systems scenario modelling and long term forecasting of hourly electricity demand

Directory of Open Access Journals (Sweden)

Poul Alberg Østergaard

2015-06-01

Full Text Available The Danish energy system is undergoing a transition from a system based on storable fossil fuels to a system based on fluctuating renewable energy sources. At the same time, more of and more of the energy system is becoming electrified; transportation, heating and fuel usage in industry and elsewhere. This article investigates the development of the Danish energy system in a medium year 2030 situation as well as in a long-term year 2050 situation. The analyses are based on scenario development by the Danish Climate Commission. In the short term, it is investigated what the effects will be of having flexible or inflexible electric vehicles and individual heat pumps, and in the long term it is investigated what the effects of changes in the load profiles due to changing weights of demand sectors are. The analyses are based on energy systems simulations using EnergyPLAN and demand forecasting using the Helena model. The results show that even with a limited short-term electric car fleet, these will have a significant effect on the energy system; the energy system’s ability to integrated wind power and the demand for condensing power generation capacity in the system. Charging patterns and flexibility have significant effects on this. Likewise, individual heat pumps may affect the system operation if they are equipped with heat storages. The analyses also show that the long-term changes in electricity demand curve profiles have little impact on the energy system performance. The flexibility given by heat pumps and electric vehicles in the long-term future overshadows any effects of changes in hourly demand curve profiles.

Mechanical demands of kettlebell swing exercise.

Science.gov (United States)

Lake, Jason P; Lauder, Mike A

2012-12-01

The aims of this study were to establish mechanical demands of kettlebell swing exercise and provide context by comparing them to mechanical demands of back squat and jump squat exercise. Sixteen men performed 2 sets of 10 swings with 16, 24, and 32 kg, 2 back squats with 20, 40, 60, and 80% 1-repetition maximum (1RM), and 2 jump squats with 0, 20, 40, and 60% 1RM. Sagittal plane motion and ground reaction forces (GRFs) were recorded during swing performance, and GRFs were recorded during back and jump squat performances. Net impulse, and peak and mean propulsion phase force and power applied to the center of mass (CM) were obtained from GRF data and kettlebell displacement and velocity from motion data. The results of repeated measures analysis of variance showed that all swing CM measures were maximized during the 32-kg condition but that velocity of the kettlebell was maximized during the 16-kg condition; displacement was consistent across different loads. Peak and mean force tended to be greater during back and jump squat performances, but swing peak and mean power were greater than back squat power and largely comparable with jump squat power. However, the highest net impulse was recorded during swing exercise with 32 kg (276.1 ± 45.3 N·s vs. 60% 1RM back squat: 182.8 ± 43.1 N·s, and 40% jump squat: 231.3 ± 47.1 N·s). These findings indicate a large mechanical demand during swing exercise that could make swing exercise a useful addition to strength and conditioning programs that aim to develop the ability to rapidly apply force.

Evaporative demand, transpiration, and photosynthesis: How are they changing?

Science.gov (United States)

Farquhar, G. D.; Roderick, M. L.

2009-04-01

Carbon dioxide concentration is increasing. This affects photosynthesis via increases in substrate availability (Farquhar et al. 1980). It reduces the amount of water transpired by plants to fix a given amount of carbon into an organic form; i.e it increases transpiration efficiency (Wong et al. 1979). It also warms the earth's surface. It is commonly supposed that this warming causes an increase in evaporative demand - the rate of water loss from a wet surface. This supposition has then been extended to effects on plant water availability, with the idea that there would be offsets to the gains in productivity associated with increased transpiration efficiency. The assumption that increased temperature means increased evaporative demand has also been applied to global maps of changes in soil water content. However, observations of pan evaporation rate show that this measure of evaporative demand has been decreasing in most areas examined over the last few decades. We reconcile these observations with theory by noting that, on long time scales, warming also involves water bodies, so that the vapour pressure at the earth's surface also increases. Using the physics of pan evaporation (Rotstayn et al. 2006) we show that the reduction in evaporative demand has been associated with two main effects, (1) "dimming", a reduction in sunlight received at the earth's surface because of aerosols and clouds, being the first phenomenon identified (Roderick and Farquhar 2002), and (2) "stilling", a reduction in wind speed, being the second (Roderick et al. 2007). We show that better accounting for changes in evaporative demand is important for estimating soil water changes, particularly in regions where precipitation exceeds evaporative demand (i.e where there are rivers) (Hobbins et al. 2008). We synthesise some of these results with others on vegetation change. References: Farquhar, GD, von Caemmerer, S, and Berry, JA, 1980: A biochemical model of photosynthetic CO2 assimilation

[Cigarette taxes and demand in Colombia].

Science.gov (United States)

Maldonado, Norman; Llorente, Blanca; Deaza, Javier

2016-10-01

Estimate price and income elasticities of aggregate demand for cigarettes in Colombia, by controlling for structural market changes since the late 1990s, to identify policy opportunities for taxes that could improve public health and increase tax revenues. Measurement of aggregate demand for cigarettes using gross income reported on value-added tax returns submitted to Colombia's National Tax and Customs Office (DIAN is the acronym in Spanish) by the tobacco product manufacturing industry, subtracting exports. A quarterly time series was obtained for the period 1994-2014. The econometric estimation using two-stage least squares controls for price endogeneity and uses a set of dummy variables to control for structural changes in the market and in its regulation. Demand is, from a statistical standpoint, sensitive to price and to income. Price elasticity of demand is -0.78 and income elasticity is 0.61. Inelastic demand implies that it is possible, through cigarette excise taxes, to meet public health targets and increase revenues simultaneously. The results also suggest that the considerable increase in household income in Colombia in the first decade of the 21st century increased purchasing power, which, lacking an accompanying tax increase, promoted cigarette consumption, with negative effects on public health, and wasted an opportunity to increase tax revenues.

Demand-controlling marketing of electric utilities

Energy Technology Data Exchange (ETDEWEB)

Raffee, H; Fritz, W

1980-01-01

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

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

Science.gov (United States)

Bridger, Robert S; Brasher, Kate

2011-09-01

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

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

NARCIS (Netherlands)

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

2001-01-01

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

Uncapacitated facility location problem with self-serving demands

Directory of Open Access Journals (Sweden)

E Monabbati

2013-12-01

Full Text Available In classical uncapacitated facility location problems (UFLP the goal is to satisfy requirements of some demand points by setting up some servers, among potential facility locations, such that the total cost including service costs and fixed costs are minimized. In this paper a generalization of UFLP is considered in which some demand points, called self-serving, could be served exclusively by a new server at that point. Numerical experiments show that near optimal solutions are achieved by the proposed method.

Nodal price volatility reduction and reliability enhancement of restructured power systems considering demand-price elasticity

International Nuclear Information System (INIS)

Goel, L.; Wu, Qiuwei; Wang, Peng

2008-01-01

With the development of restructured power systems, the conventional 'same for all customers' electricity price is getting replaced by nodal prices. Electricity prices will fluctuate with time and nodes. In restructured power systems, electricity demands will interact mutually with prices. Customers may shift some of their electricity consumption from time slots of high electricity prices to those of low electricity prices if there is a commensurate price incentive. The demand side load shift will influence nodal prices in return. This interaction between demand and price can be depicted using demand-price elasticity. This paper proposes an evaluation technique incorporating the impact of the demand-price elasticity on nodal prices, system reliability and nodal reliabilities of restructured power systems. In this technique, demand and price correlations are represented using the demand-price elasticity matrix which consists of self/cross-elasticity coefficients. Nodal prices are determined using optimal power flow (OPF). The OPF and customer damage functions (CDFs) are combined in the proposed reliability evaluation technique to assess the reliability enhancement of restructured power systems considering demand-price elasticity. The IEEE reliability test system (RTS) is simulated to illustrate the developed techniques. The simulation results show that demand-price elasticity reduces the nodal price volatility and improves both the system reliability and nodal reliabilities of restructured power systems. Demand-price elasticity can therefore be utilized as a possible efficient tool to reduce price volatility and to enhance the reliability of restructured power systems. (author)

The Job Demands-Resources Model in China: Validation and Extension

NARCIS (Netherlands)

Hu, Q.

2014-01-01

The Job Demands-Resources (JD-R) Model assumes that employee health and well-being result from the interplay between job demands and job resources. Based on its openheuristic nature, the JD-R model can be applied to various occupational settings, irrespective of the particular demands and resources

Money demand in post-crisis Russia: De-dollarisation and re-monetisation

OpenAIRE

Korhonen, Iikka; Mehrotra, Aaron

2007-01-01

Estimating money demand functions for Russia following the 1998 crisis, we find a stable money demand relationship when augmented by a deterministic trend signifying falling velocity. As predicted by theory, higher income boosts demand for real rouble balances and the income elasticity of money is close to unity. Inflation affects the adjustment towards equilibrium, while broad money shocks lead to higher inflation. We also show that exchange rate fluctuations have a considerable influence on...

Emotional Demands at Work and the Risk of Clinical Depression

DEFF Research Database (Denmark)

Vammen, Marianne Agergaard; Mikkelsen, Sigurd; Kolstad, Henrik

2016-01-01

of clinical depression were diagnosed. Emotional demands were examined as perceived and content-related emotional demands, individually reported and work-unit based. Support, meaningful work, and enrichment were considered as potential effect modifiers. Results: Individually reported perceived emotional......Objective: This study is a 2-year follow-up study of different dimensions of work-related emotional demands as a predictor for clinical depression. Methods: In a two-wave study, 3224 (72%) public employees from 474 work-units participated twice by filling in questionnaires. Sixty-Two cases...... demands predicted depression (odds ratio: 1.40; 95% confidence intervals: 1.02 to 1.92). The work-unit based odds ratio was in the same direction, though not significant. Content-related emotional demands did not predict depression. Support, meaningful work, and enrichment did not modify the results...

The impact of small scale cogeneration on the gas demand at distribution level

International Nuclear Information System (INIS)

Vandewalle, J.; D’haeseleer, W.

2014-01-01

Highlights: • Impact on the gas network of a massive implementation of cogeneration. • Distributed energy resources in a smart grid environment. • Optimisation of cogeneration scheduling. - Abstract: Smart grids are often regarded as an important step towards the future energy system. Combined heat and power (CHP) or cogeneration has several advantages in the context of the smart grid, which include the efficient use of primary energy and the reduction of electrical losses through transmission. However, the role of the gas network is often overlooked in this context. Therefore, this work presents an analysis of the impact of a massive implementation of small scale (micro) cogeneration units on the gas demand at distribution level. This work shows that using generic information in the simulations overestimates the impact of CHP. Furthermore, the importance of the thermal storage tank capacity on the impact on the gas demand is shown. Larger storage tanks lead to lower gas demand peaks and hence a lower impact on the gas distribution network. It is also shown that the use of an economically led controller leads to similar results compared to classical heat led control. Finally, it results that a low sell back tariff for electricity increases the impact of cogeneration on the gas demand peak

Ex-post evaluations of demand forecast accuracy

DEFF Research Database (Denmark)

Nicolaisen, Morten Skou; Driscoll, Patrick Arthur

2014-01-01

Travel demand forecasts play a crucial role in the preparation of decision support to policy makers in the field of transport planning. The results feed directly into impact appraisals such as cost benefit analyses and environmental impact assessments, which are mandatory for large public works...... projects in many countries. Over the last couple of decades there has been an increasing attention to the lack of demand forecast accuracy, but since data availability for comprehensive ex- post appraisals is problematic, such studies are still relatively rare. The present paper presents a review...... of the largest ex-post studies of demand forecast accuracy for transport infrastructure projects. The focus is twofold; to provide an overview of observed levels of demand forecast inaccuracy and to explore the primary explanations offered for the observed inaccuracy. Inaccuracy in the form of both bias...

Modelling energy demand of Croatian industry sector

DEFF Research Database (Denmark)

Medić, Zlatko Bačelić; Pukšec, Tomislav; Mathiesen, Brian Vad

2014-01-01

Industry represents one of the most interesting sectors when analysing Croatian final energy demand. Croatian industry represents 20% of nation's GDP and employs 25% of total labour force making it a significant subject for the economy. Today, with around 60 PJ of final energy demand...... it is the third most energy intensive sector in Croatia after transport and households. Implementing mechanisms that would lead to improvements in energy efficiency in this sector seems relevant. Through this paper, long-term energy demand projections for Croatian industry will be shown. The central point...... for development of the model will be parameters influencing the industry in Croatia. Energy demand predictions in this paper are based upon bottom-up approach model. IED model produces results which can be compared to Croatian National Energy Strategy. One of the conclusions shown in this paper is significant...

China's Rare Earth Supply Chain: Illegal Production, and Response to new Cerium Demand

Science.gov (United States)

Nguyen, Ruby Thuy; Imholte, D. Devin

2016-07-01

As the demand for personal electronic devices, wind turbines, and electric vehicles increases, the world becomes more dependent on rare earth elements. Given the volatile, Chinese-concentrated supply chain, global attempts have been made to diversify supply of these materials. However, the overall effect of supply diversification on the entire supply chain, including increasing low-value rare earth demand, is not fully understood. This paper is the first attempt to shed some light on China's supply chain from both demand and supply perspectives, taking into account different Chinese policies such as mining quotas, separation quotas, export quotas, and resource taxes. We constructed a simulation model using Powersim Studio that analyzes production (both legal and illegal), production costs, Chinese and rest-of-world demand, and market dynamics. We also simulated new demand of an automotive aluminum-cerium alloy in the US market starting from 2018. Results showed that market share of the illegal sector has grown since 2007-2015, ranging between 22% and 25% of China's rare earth supply, translating into 59-65% illegal heavy rare earths and 14-16% illegal light rare earths. There will be a shortage in certain light and heavy rare earths given three production quota scenarios and constant demand growth rate from 2015 to 2030. The new simulated Ce demand would require supply beyond that produced in China. Finally, we illustrate revenue streams for different ore compositions in China in 2015.

[Job Demands-Resources, exhaustion and work engagement in a long-term care institution].

Science.gov (United States)

Conway, P M; Neri, L; Campanini, P; Francioli, L; Camerino, D; Punzi, S; Fichera, G P; Costa, G

2012-01-01

In this study, we aimed at testing the main hypotheses of the Job Demands-Resources model (JD-R) in a sample of employees (n = 205, mainly healthcare workers) of a long-term care institution located in Northern Italy. Hierarchical linear regression analyses show that almost all job demands considered were significantly associated with higher general psycho-physical exhaustion (beta ranging from 0.14 to 0.29), whereas more unfavourable scores in all job resources were associated with lower work engagement (from -0.27 to -0.51). However, also significant cross-over associations were observed, mainly between job resources and exhaustion, with effect sizes comparable with those found for the relationships between job demands and exhaustion. Hence, our study only partially supports the JD-R model. Implications of results for work-related stress management are finally discussed.

Optimal real time cost-benefit based demand response with intermittent resources

International Nuclear Information System (INIS)

Zareen, N.; Mustafa, M.W.; Sultana, U.; Nadia, R.; Khattak, M.A.

2015-01-01

Ever-increasing price of conventional energy resources and related environmental concern enforced to explore alternative energy sources. Inherent uncertainty of power generation and demand being strongly influenced by the electricity market has posed severe challenges for DRPs (Demand Response Programs). Definitely, the success of such uncertain energy systems under new market structures is critically decided by the advancement of innovative technical and financial tools. Recent exponential growth of DG (distributed generations) demanded both the grid reliability and financial cost–benefits analysis for deregulated electricity market stakeholders. Based on the SGT (signaling game theory), the paper presents a novel user-aware demand-management approach where the price are colligated with grid condition uncertainties to manage the peak residential loads. The degree of information disturbances are considered as a key factor for evaluating electricity bidding mechanisms in the presence of independent multi-generation resources and price-elastic demand. A correlation between the cost–benefit price and variable reliability of grid is established under uncertain generation and demand conditions. Impacts of the strategies on load shape, benefit of customers and the reduction of energy consumption are inspected and compared with Time-of-Used based DRPs. Simulation results show that the proposed DRP can significantly reduce or even eliminate peak-hour energy consumption, leading to a substantial raise of revenues with 18% increase in the load reduction and a considerable improvement in system reliability is evidenced. - Highlights: • Proposed an optimal real time cost-benefit based demand response model. • Used signaling game theory for the information disturbances in deregulated market. • Introduced a correlation between the cost–benefit price and variable grid reliability. • Derive robust bidding strategies for utility/customers successful participation. �

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

Science.gov (United States)

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

2015-12-01

Karasek's job demands-control (JDC) model posits that job control can buffer against the harmful effects of demands experienced by employees. A large volume of JDC research has obtained support for the main effects of demands and control, but not the interactive effects. Recent research on the challenge-hindrance stressors framework, however, found that work stressors may not always be deleterious, suggesting alternative hypotheses about the effects of demands and control. The present study therefore examined competing hypotheses concerning the effects of job demands on occupational health outcomes. Using a sample of 316 employees in a Chinese manufacturing company, we found that, consistent with the challenge-hindrance framework, production demands were challenge stressors associated with favourable outcomes (i.e. job satisfaction and psychological well-being). In addition, results showed that the interactive role of job control depended on the nature of outcome variables. Future recommendations and implications of findings are discussed. Copyright © 2014 John Wiley & Sons, Ltd.

Sensitivity of district heating system operation to heat demand reductions and electricity price variations: A Swedish example

International Nuclear Information System (INIS)

Åberg, M.; Widén, J.; Henning, D.

2012-01-01

In the future, district heating companies in Sweden must adapt to energy efficiency measures in buildings and variable fuel and electricity prices. Swedish district heating demands are expected to decrease by 1–2% per year and electricity price variations seem to be more unpredictable in the future. A cost-optimisation model of a Swedish local district heating system is constructed using the optimisation modelling tool MODEST. A scenario for heat demand changes due to increased energy efficiency in buildings, combined with the addition of new buildings, is studied along with a sensitivity analysis for electricity price variations. Despite fears that heat demand reductions will decrease co-generation of clean electricity and cause increased global emissions, the results show that anticipated heat demand changes do not increase the studied system's primary energy use or global CO 2 emissions. The results further indicate that the heat production plants and the fuels used within the system have crucial importance for the environmental impact of district heat use. Results also show that low seasonal variations in electricity price levels with relatively low winter prices promote the use of electric heat pumps. High winter prices on the other hand promote co-generation of heat and electricity in CHP plants. -- Highlights: ► A MODEST optimisation model of the Uppsala district heating system is built. ► The impact of heat demand change on heat and electricity production is examined. ► An electricity price level sensitivity analysis for district heating is performed. ► Heat demand changes do not increase the primary energy use or global CO 2 emissions. ► Low winter prices promote use of electric heat pumps for district heating production.

A Note on R&D and Price Elasticity of Demand

DEFF Research Database (Denmark)

Schröder, Philipp J.H.; Schumacher, Dieter; Lucke, Dorothea

2005-01-01

This note explores the relationship between the price elasticity of demand and the R&D intensity of the product. We introduce the concept of R&D intensity into a standard Dixit-Stiglitz/Krugman-type setting. R&D activity is treated as a fixed cost of production. Within this framework, sectors...... with a higher R&D intensity show a lower price elasticity of demand. This proposition is confirmed by an empirical investigation of export demand for manufactured goods from major industrialised countries. Consequently, real exchange rate changes have an impact on the commodity structure of exports....

A comprehensive assessment of the life cycle energy demand of passive houses

International Nuclear Information System (INIS)

Stephan, André; Crawford, Robert H.; Myttenaere, Kristel de

2013-01-01

Highlights: • The life cycle energy demand of a passive house (PH) is measured over 100 years. • Embodied, operational and user transport energy demand are considered. • Embodied energy represents the highest energy consumption in all variations. • A PH might not save energy compared to a standard house. • A poorly insulated city apartment can use less energy than a best case suburban PH. - Abstract: Certifications such as the Passive House aim to reduce the final space heating energy demand of residential buildings. The latter are responsible for a significant share of final energy consumption in Europe of which nearly 70% is associated with space conditioning, notably heating. The improvement of the energy efficiency of residential buildings, in terms of space heating, can therefore reduce their total energy demand. However, most certifications totally overlook other energy requirements associated with residential buildings. Studies on passive houses do not take into consideration the embodied energy required to manufacture the building materials, especially the large amount of insulation required to achieve high operational efficiencies. At an urban scale, most passive houses are single family detached houses located in low density suburbs with a high car usage, resulting in considerable transport related energy demand. This paper analyses the total life cycle energy demand of a typical Belgian passive house, comprising embodied, operational and transport energy. It relies on a comprehensive technique developed by Stephan et al. [1] and conducts a parametric analysis as well as a comparison to alternative building types. Results show that current building energy efficiency certifications might not ensure a lower energy demand and can, paradoxically result in an increased energy consumption because of their limited scope. More comprehensive system boundaries should be used to make sure that net energy savings do occur. The embodied energy of passive

An analytical approach to activating demand elasticity with a demand response mechanism

International Nuclear Information System (INIS)

Clastres, Cedric; Khalfallah, Haikel

2015-01-01

The aim of this work is to demonstrate analytically the conditions under which activating the elasticity of consumer demand could benefit social welfare. We have developed an analytical equilibrium model to quantify the effect of deploying demand response on social welfare and energy trade. The novelty of this research is that it demonstrates the existence of an optimal area for the price signal in which demand response enhances social welfare. This optimal area is negatively correlated to the degree of competitiveness of generation technologies and the market size of the system. In particular, it should be noted that the value of un-served energy or energy reduction which the producers could lose from such a demand response scheme would limit its effectiveness. This constraint is even greater if energy trade between countries is limited. Finally, we have demonstrated scope for more aggressive demand response, when only considering the impact in terms of consumer surplus. (authors)

Towards a Job Demands-Resources Health Model: Empirical Testing with Generalizable Indicators of Job Demands, Job Resources, and Comprehensive Health Outcomes

OpenAIRE

Brauchli, Rebecca; Jenny, Gregor J.; Füllemann, Désirée; Bauer, Georg F.

2015-01-01

Studies using the Job Demands-Resources (JD-R) model commonly have a heterogeneous focus concerning the variables they investigate?selective job demands and resources as well as burnout and work engagement. The present study applies the rationale of the JD-R model to expand the relevant outcomes of job demands and job resources by linking the JD-R model to the logic of a generic health development framework predicting more broadly positive and negative health. The resulting JD-R health model ...

The impact of object size and precision demands on fatigue during computer mouse use

DEFF Research Database (Denmark)

Aasa, Ulrika; Jensen, Bente Rona; Sandfeld, Jesper

2011-01-01

use demands were of influence. Also, we investigated performance (number of rectangles painted), and whether perceived fatigue was paralleled by local muscle fatigue or tissue oxygenation. Ten women performed the task for three conditions (crossover design). At condition 1, rectangles were 45 × 25 mm...... not differ between conditions. In conclusion, computer work tasks imposing high visual and motor demands, and with high performance, seemed to have an influence on eye fatigue....... ratio was 1:8. The results showed increased self-reported fatigue over time, with the observed increase greater for the eyes, but no change in physiological responses. Condition 2 resulted in higher performance and increased eye fatigue. Perceived fatigue in the muscles or physiological responses did...

Demand side management for commercial buildings using an in line heat pump water heating methodology

International Nuclear Information System (INIS)

Rankin, Riaan; Rousseau, Pieter G.; Eldik, Martin van

2004-01-01

Most of the sanitary hot water used in South African buildings is heated by means of direct electrical resistance heaters. This is one of the major contributors to the undesirably high morning and afternoon peaks imposed on the national electricity supply grid. For this reason, water heating continues to be of concern to the electricity supplier, ESCOM. Previous studies, conducted by the Potchefstroom University for Christian Higher Education in South Africa, indicated that extensive application of the so called inline heat pump water heating methodology in commercial buildings could result in significant demand side management savings to ESKOM. Furthermore, impressive paybacks can be obtained by building owners who choose to implement the design methodology on existing or new systems. Currently, a few examples exist where the design methodology has been successfully implemented. These installations are monitored with a fully web centric monitoring system that allows 24 h access to data from each installation. Based on these preliminary results, a total peak demand reduction of 108 MW can be achieved, which represents 18% of the peak load reduction target set by ESKOM until the year 2015. This represents an avoided cost of approximately MR324 (ZAR) [Int J Energy Res 25(4) (1999) 2000]. Results based on actual data from the monitored installations shows a significant peak demand reduction for each installation. In one installation, a hotel with an occupancy of 220 people, the peak demand contribution of the hot water installation was reduced by 86%, realizing a 36% reduction in peak demand for the whole building. The savings incurred by the building owner also included significant energy consumption savings due to the superior energy efficiency of the heat pump water heater. The combined savings result in a conservatively calculated straight payback period of 12.5 months, with an internal rate of return of 98%. The actual cost of water heating is studied by

Demanding Dynamics - Demand articulation of intermediary organisations in emerging pharmaceutical innovations

NARCIS (Netherlands)

Boon, W.P.C.

2008-01-01

User involvement in emerging technological fields is carried by so-called demand articulation processes. These demand articulation processes are interactive learning processes in which stakeholders try to address what they perceive as important characteristics of, and to unravel preferences for an

Interaction between daily load demand curve and management of hydro-thermal generation system

International Nuclear Information System (INIS)

Granelli, G.; Montagna, M.; Pasini, G.; Innorta, M.; Marannino, P.

1993-01-01

The influence that the behaviour of the daily load demand curve has on the management of a hydro-thermal generation system is considered. The aim of this paper is to show the improvements that can be achieved by suitable load management techniques capable of flattening the load demand curve. The analysis is carried out by using a hydro-thermal scheduling program and a thermal unit dynamic dispatch procedure. The possibility of properly re-committing the available thermal units is also taken into account. The economical and technical convenience of shutting down less economical thermal units operating near the lower generations limits is verified. Finally, some considerations are made about the possible use of the thermal generation incremental costs as a tool for planning the end users' kWh prices, even in the short term. The results refer to a system with characteristics similar to those of the Italian one. In determining the daily load demand curves, the characteristics of load demand in Italy as well as in other European countries are taken into account

Demand-Driven Success: Designing Your PDA Experiment

OpenAIRE

Hillen, Charles; Johnson-Grau, Glenn

2012-01-01

Initiating demand-driving acquisition is daunting. Implications for developing a sustainable budget model, choosing a vendor, controlling metadata, monitoring purchases and developing invoice workflows are significant areas of concern that require determinative planning. From mid-February through August 2011, Loyola Marymount University conducted a pilot using demand-driven acquisition; the result of this successful experiment was the library’s decision to fully integrate this purchasing mode...

Oil supply and demand

International Nuclear Information System (INIS)

Rech, O.

2006-01-01

The year 2004 saw a change in the oil market paradigm that was confirmed in 2005. Despite a calmer geopolitical context, prices continued to rise vigorously. Driven by world demand, they remain high as a result of the saturation of production and refining capacity. The market is still seeking its new equilibrium. (author)

Oil supply and demand

Energy Technology Data Exchange (ETDEWEB)

Rech, O

2006-07-01

The year 2004 saw a change in the oil market paradigm that was confirmed in 2005. Despite a calmer geopolitical context, prices continued to rise vigorously. Driven by world demand, they remain high as a result of the saturation of production and refining capacity. The market is still seeking its new equilibrium. (author)

Heroin and saccharin demand and preference in rats.

Science.gov (United States)

Schwartz, Lindsay P; Kim, Jung S; Silberberg, Alan; Kearns, David N

2017-09-01

Several recent studies have investigated the choice between heroin and a non-drug alternative reinforcer in rats. A common finding in these studies is that there are large individual differences in preference, with some rats preferring heroin and some preferring the non-drug alternative. The primary goal of the present study was to determine whether individual differences in how heroin or saccharin is valued, based on demand analysis, predicts choice. Rats lever-pressed for heroin infusions and saccharin reinforcers on fixed-ratio schedules. The essential value of each reinforcer was obtained from resulting demand curves. Rats were then trained on a mutually exclusive choice procedure where pressing one lever resulted in heroin and pressing another resulted in saccharin. After seven sessions of increased access to heroin or saccharin, rats were reexposed to the demand and choice procedures. Demand for heroin was more elastic than demand for saccharin (i.e., heroin had lower essential value than saccharin). When allowed to choose, most rats preferred saccharin. The essential value of heroin, but not saccharin, predicted preference. The essential value of both heroin and saccharin increased following a week of increased access to heroin, but similar saccharin exposure had no effect on essential value. Preference was unchanged after increased access to either reinforcer. Heroin-preferring rats differed from saccharin-preferring rats in how they valued heroin, but not saccharin. To the extent that choice models addiction-related behavior, these results suggest that overvaluation of opioids specifically, rather than undervaluation of non-drug alternatives, could identify susceptible individuals. Copyright © 2017 Elsevier B.V. All rights reserved.

Ad libitum or demand/semi-demand feeding versus scheduled interval feeding for preterm infants.

Science.gov (United States)

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

Refrigerated Warehouse Demand Response Strategy Guide

Energy Technology Data Exchange (ETDEWEB)

Scott, Doug [VaCom Technologies, San Luis Obispo, CA (United States); Castillo, Rafael [VaCom Technologies, San Luis Obispo, CA (United States); Larson, Kyle [VaCom Technologies, San Luis Obispo, CA (United States); Dobbs, Brian [VaCom Technologies, San Luis Obispo, CA (United States); Olsen, Daniel [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2015-11-01

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 lighting 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.

Challenge and hindrance demands lead to employees' health and behaviours through intrinsic motivation.

Science.gov (United States)

Kim, Minseo; Beehr, Terry A

2018-01-12

Based on the job demand-resource theory, this study examined the differential relationships of two types of job demands, challenge and hindrance stressors, with three outcomes: ill health, organizational citizenship behaviour, and work engagement. These relationships were mediated by two personal resources: psychological empowerment and organization-based self-esteem (OBSE). Data were collected at two separate points, 2 weeks apart. With 336 full-time U.S. employees, results from path analysis indicated that the challenge stressor, workload, was positively related to psychological empowerment and OBSE, both of which were in turn positively related to good work behaviours as well as negatively related to ill health, an indication that employees experienced physical symptoms and psychological strains. In contrast, hindrance stressors (role stressors and interpersonal conflict) showed the opposite patterns of relationships with these intermediate outcomes, resulting in less empowerment and OBSE. Overall, findings suggested that psychological empowerment and OBSE were important intrinsic motivational mechanisms through which some stressors (especially hindrance demands) can promote employees' favourable work behaviours as well as alleviate the negative health outcomes. Copyright © 2018 John Wiley & Sons, Ltd.

Microeconomics and the demand for space heating

Energy Technology Data Exchange (ETDEWEB)

Fisk, D.J.

1977-12-01

The techniques of economic utility theory are combined with the technical equations for heat loss from a dwelling to give insight into the variation of consumer demand for space heating. A theoretical relationship is established between the performance of the occupied dwelling as the external temperature falls and the short-run income elasticity of energy demand. The analysis is applied to studies of UK heating practice in the 1950s and the implied indifference map for thermal comfort deduced. This indifference map is found to show a considerable economic propensity to absorb some of the potential savings from energy conservation measurements in higher internal temperatures. The effect found is sufficiently large to have consequences for future energy planning if it were still present in the UK domestic sector. The analysis highlights a number of points that should aid the interpretation of field experiments on domestic energy consumption. In particular, it is shown that unless great care is taken to separate out the technical and economic origins of internal temperature variation, the results of field studies on the effectiveness of conservation techniques may only be of shortlived value.

The moderating role of personal resources in the relationship between psychosocial job demands and health: a cross-sectional study

Science.gov (United States)

Mayerl, Hannes; Stolz, Erwin; Großschädl, Franziska; Rásky, Éva; Freidl, Wolfgang

2017-01-01

Objective The main objective of this research was to investigate the buffering effects of an individual’s physical, mental and social resources in the relationship between psychosocial job demands and (1) health symptoms, (2) mental strain and (3) the body mass index (BMI), respectively. Methods We performed moderated regression analysis to examine data from a large cross-sectional survey of an Austrian employee sample (n=9434). Results The results revealed a robust association between psychosocial job demands and health symptoms as well as mental strain, but only a weak relationship between psychosocial job demands and BMI. Although the personal resources showed a positive effect on health symptoms and mental strain, only weak evidence was found for the hypothesised interaction with psychosocial job demands. Solely the physical fitness of a person was found to mitigate the impact of psychosocial job demands on health symptoms. Conclusions In conclusion, personal resources substantially accounted for the prediction of health. However, the interactions between psychosocial job demands and personal resources only slightly contributed to explaining the variation in health. PMID:28851776

Geospatial Analysis of the Building Heat Demand and Distribution Losses in a District Heating Network

Directory of Open Access Journals (Sweden)

Tobias Törnros

2016-11-01

Full Text Available The district heating (DH demand of various systems has been simulated in several studies. Most studies focus on the temporal aspects rather than the spatial component. In this study, the DH demand for a medium-sized DH network in a city in southern Germany is simulated and analyzed in a spatially explicit approach. Initially, buildings are geo-located and attributes obtained from various sources including building type, ground area, and number of stories are merged. Thereafter, the annual primary energy demand for heating and domestic hot water is calculated for individual buildings. Subsequently, the energy demand is aggregated on the segment level of an existing DH network and the water flow is routed through the system. The simulation results show that the distribution losses are overall the highest at the end segments (given in percentage terms. However, centrally located pipes with a low throughflow are also simulated to have high losses. The spatial analyses are not only useful when addressing the current demand. Based on a scenario taking into account the refurbishment of buildings and a decentralization of energy production, the future demand was also addressed. Due to lower demand, the distribution losses given in percentage increase under such conditions.

The world energy demand in 2007: How high oil prices impact the global energy demand? June 9, 2008

International Nuclear Information System (INIS)

2008-01-01

How high oil prices impact the global energy demand? The growth of energy demand continued to accelerate in 2007 despite soaring prices, to reach 2,8 % (+ 0,3 point compared to 2006). This evolution results from two diverging trends: a shrink in energy consumption in most of OECD countries, except North America, and a strong increase in emerging countries. Within the OECD, two contrasting trends can be reported, that compensate each other partially: the reduction of energy consumption in Japan (-0.8%) and in Europe (-1.2%), particularly significant in the EU-15 (-1.9%); the increase of energy consumption in North America (+2%). Globally, the OECD overall consumption continued to increase slightly (+0.5%), while electricity increased faster (2,1%) and fuels remained stable. Elsewhere, the strong energy demand growth remained very dynamic (+5% for the total demand, 8% for electricity only), driven by China (+7.3%). The world oil demand increased by 1% only, but the demand has focused even more on captive end usages, transports and petrochemistry. The world gasoline and diesel demand increased by around 5,7% in 2007, and represents 53% of the total oil products demand in 2007 (51% in 2006). If gasoline and diesel consumption remained quasi-stable within OECD countries, the growth has been extremely strong in the emerging countries, despite booming oil prices. There are mainly two factors explaining this evolution where both oil demand and oil prices increased: Weak elasticity-prices to the demand in transport and petrochemistry sectors Disconnection of domestic fuel prices in major emerging countries (China, India, Latin America) compared to world oil market prices Another striking point is that world crude oil and condensate production remained almost stable in 2007, hence the entire demand growth was supported by destocking. During the same period, the OPEC production decreased by 1%, mainly due to the production decrease in Saudi Arabia, that is probably more

Development of reader for the demand data from compound demand meter for power supply/demand (CDM). Development of recommended tools for load leveling in existing works; Denryoku jukyuyo fukugo keiki kara no demand data yomitori sochi no kaihatsu. Kisetsu kojo no fuka heijunka suisho tool no kaihatsu

Energy Technology Data Exchange (ETDEWEB)

Sakamoto, S. [Kansai Electric Power Co. Inc., Osaka (Japan)

1997-10-10

Kansai Electric Power has developed a system which reads the demand data for 30min. stored in the compound demand meter for power supply/demand (CDM), and prints the load curves. It is for customers of high-voltage power of less than 500kW, where load management is less extensive than that in larger users, for initial consulting on improvement of load factor (recommendation of heat storage contracts). It is to be installed on the spot to display the load curves, to allow the expert visiting the site to issue initial proposals immediately. It displays `daily demands by time zone` instead of `monthly power consumption` previously provided, and makes the graph of demands by time zone. It is designed to be compact, light, and easily and safely handled. The field test results indicate that the system can be sufficiently practical with the major performance items. 4 figs., 1 tab.

The analysis of indiference and the price elasticity of demand between different categories of agricultural products

Directory of Open Access Journals (Sweden)

Vukadinović Predrag

2017-01-01

Full Text Available In this paper, the analysis of the price elasticity of demand of four different categories of agricultural products in the Republic of Serbia was described. Differentiating the price and demand of these products by sales points, and using the least squares approximation method, the elasticity for all different agricultural categories was expressed in the functional form. According to this, the coefficients of elasticity of the price and demand were computed and between different agricultural categories were analyzed. The results we obtained show that the market of agricultural products in Serbia is mostly inelastic because the coefficients of inelasticity and indifference of demand to change of prices, are dominant. The influence of factors on the elasticity of demand that are not of price character, proved to be very pronounced. The relationship of the two segments of agricultural market (markets and shops was also analysed and it was demonstrated that these two segments have a slight correlation.

Future Electricity Demand of the Emerging European Countries and the CIS Countries

Directory of Open Access Journals (Sweden)

Mehmet Fatih Bayramoglu

2016-10-01

Full Text Available Nowadays, one of the leading factors used in the evaluation of a country’s economic development is energy consumption. Because of economic growth, demand for energy is also increasing. In this study, the emerging European countries’ (the Czech Republic, Poland, Romania, Turkey and the CIS countries’ (Kazakhstan, Russia, Ukraine, Uzbekistan  electricity consumption has been forecasted for five years period (2015-2019. In the study, GM(1,1 Rolling Model, which is developed in the framework of Grey System Theory is used as a mathematical model for real-time forecasting. The results of the study show that there will not be a significant change in electricity demand in this two area during the 2015-2109 period.

Is the demand for alcoholic beverages in developing countries sensitive to price? Evidence from China.

Science.gov (United States)

Tian, Guoqiang; Liu, Feng

2011-06-01

Economic literature in developed countries suggests that demand for alcoholic beverages is sensitive to price, with an estimated price elasticity ranging from -0.38 for beer and -0.7 for liquor. However, few studies have been conducted in developing countries. We employ a large individual-level dataset in China to estimate the effects of price on alcohol demand. Using the data from China Health and Nutrition Survey for the years 1993, 1997, 2000, 2004 and 2006, we estimate two-part models of alcohol demand. Results show the price elasticity is virtually zero for beer and only -0.12 for liquor, which is far smaller than those derived from developed countries. Separate regressions by gender reveals the results are mainly driven by men. The central implication of this study is, while alcohol tax increases can raise government revenue, it alone is not an effective policy to reduce alcohol related problems in China.

Analysis of reactor strategies to meet world nuclear energy demands

International Nuclear Information System (INIS)

Ligon, D.M.; Brogli, R.H.

1979-07-01

A number of reactor deployment strategies for long-term nuclear system development are analyzed from a global perspective in terms of resource utilization and economic benefits. Two time frames are chosen: 1975 - 2025 and 1975 - 2050. Uranium demand for various strategies is compared with uranium supply assuming different production capabilities and resource base. The analysis shows that a given reactor deployment strategy could strongly influence the extent of uranium exploration and production. Power systems cost comparisons are made to identify clearly competitive or non-competitive reactors. The sensitivity of power cost to different uranium price projections and nuclear demands is also examined. The results indicate that breeders are necessary to support a long-term nuclear power system. Advanced converter-breeder symbiotic systems, particularly those operating on the Th/U-233 cycle, have clear advantages in terms of resources and economics

Integrated Optimization of Bus Line Fare and Operational Strategies Using Elastic Demand

Directory of Open Access Journals (Sweden)

Chunyan Tang

2017-01-01

Full Text Available An optimization approach for designing a transit service system is proposed. Its objective would be the maximization of total social welfare, by providing a profitable fare structure and tailoring operational strategies to passenger demand. These operational strategies include full route operation (FRO, limited stop, short turn, and a mix of the latter two strategies. The demand function is formulated to reflect the attributes of these strategies, in-vehicle crowding, and fare effects on demand variation. The fare is either a flat fare or a differential fare structure; the latter is based on trip distance and achieved service levels. This proposed methodology is applied to a case study of Dalian, China. The optimal results indicate that an optimal combination of operational strategies integrated with a differential fare structure results in the highest potential for increasing total social welfare, if the value of parameter ε related to additional service fee is low. When this value increases up to more than a threshold, strategies with a flat fare show greater benefits. If this value increases beyond yet another threshold, the use of skipped stop strategies is not recommended.

A Column Generation Approach to the Capacitated Vehicle Routing Problem with Stochastic Demands

DEFF Research Database (Denmark)

Christiansen, Christian Holk; Lysgaard, Jens

. The CVRPSD can be formulated as a Set Partitioning Problem. We show that, under the above assumptions on demands, the associated column generation subproblem can be solved using a dynamic programming scheme which is similar to that used in the case of deterministic demands. To evaluate the potential of our......In this article we introduce a new exact solution approach to the Capacitated Vehicle Routing Problem with Stochastic Demands (CVRPSD). In particular, we consider the case where all customer demands are distributed independently and where each customer's demand follows a Poisson distribution...

Estimating demand schedules in hedonic analysis

DEFF Research Database (Denmark)

Panduro, Toke Emil; Jensen, Cathrine Ulla; Lundhede, Thomas

The hedonic pricing method has been used extensively to obtain implicit prices for availability of urban green space, but few hedonic studies have obtained households’ preference parameters. We estimate willingness to pay functions for park availability in Copenhagen using an approach that places...... identifying restrictions on the utility function. We do this for two different measures of park availability. We apply our results to a policy scenario and show how estimates of aggregate welfare changes are highly sensitive to the measure of park availability applied. Thus, the approach in this study applies...... an alternative path for estimation of demand schedules for public goods using hedonic data. The findings also stress the importance of paying attention to how public goods are defined when undertaking welfare economic policy analyses....

Modelling curves of manufacturing feasibilities and demand

Directory of Open Access Journals (Sweden)

Soloninko K.S.

2017-03-01

Full Text Available The authors research the issue of functional properties of curves of manufacturing feasibilities and demand. Settlement of the problem, and its connection with important scientific and practical tasks. According to its nature, the market economy is unstable and is in constant movement. Economy has an effective instrument for explanation of changes in economic environment; this tool is called the modelling of economic processes. The modelling of economic processes depends first and foremost on the building of economic model which is the base for the formalization of economic process, that is, the building of mathematical model. The effective means for formalization of economic process is the creation of the model of hypothetic or imaginary economy. The building of demand model is significant for the market of goods and services. The problem includes the receiving (as the result of modelling definite functional properties of curves of manufacturing feasibilities and demand according to which one can determine their mathematical model. Another problem lies in obtaining majorant properties of curves of joint demand on the market of goods and services. Analysis of the latest researches and publications. Many domestic and foreign scientists dedicated their studies to the researches and building of the models of curves of manufacturing feasibilities and demand. In spite of considerable work of the scientists, such problems as functional properties of the curves and their practical use in modelling. The purpose of the article is to describe functional properties of curves of manufacturing feasibilities and demand on the market of goods and services on the base of modelling of their building. Scientific novelty and practical value. The theoretical regulations (for functional properties of curves of manufacturing feasibilities and demand received as a result of the present research, that is convexity, give extra practical possibilities in a microeconomic

Demand scenarios, worldwide

Energy Technology Data Exchange (ETDEWEB)

Schaefer, A [Massachusetts Inst. of Technology, Center for Technology, Policy and Industrial Development and the MIT Joint Program on the Science and Policy of Global Change, Cambridge, MA (United States)

1996-11-01

Existing methods are inadequate for developing aggregate (regional and global) and long-term (several decades) passenger transport demand scenarios, since they are mainly based on simple extensions of current patterns rather than causal relationships that account for the competition among transport modes (aircraft, automobiles, buses and trains) to provide transport services. The demand scenario presented in this paper is based on two empirically proven invariances of human behavior. First, transport accounts for 10 to 15 percent of household total expenditures for those owning an automobile, and around 5 percent for non-motorized households on average (travel money budget). Second, the mean time spent traveling is approximately one hour per capita per day (travel time budget). These two budgets constraints determine the dynamics of the scenario: rising income increases per capita expenditure on travel which, in turn, increase demand for mobility. Limited travel time constraints travelers to shift to faster transport systems. The scenario is initiated with the first integrated historical data set on traffic volume in 11 world regions and the globe from 1960 to 1990 for all major modes of motorized transport. World average per capita traffic volume, which was 1,800 kilometers in 1960 and 4,2090 in 1990, is estimated to rise to 7,900 kilometers in 2020 - given a modest average increase in Gross World Product of 1.9% per year. Higher economic growth rates in Asian regions result in an increase in regional per capita traffic volume up to a factor of 5.3 from 1990 levels. Modal splits continue shifting to more flexible and faster modes of transport. At one point, passenger cars can no longer satisfy the increasing demand for speed (i.e. rising mobility within a fixed time budget). In North America it is estimated that the absolute traffic volume of automobiles will gradually decline starting in the 2010s. (author) 13 figs., 6 tabs., 35 refs.

The design of optimal electric power demand management contracts

Science.gov (United States)

Fahrioglu, Murat

1999-11-01

Our society derives a quantifiable benefit from electric power. In particular, forced outages or blackouts have enormous consequences on society, one of which is loss of economic surplus. Electric utilities try to provide reliable supply of electric power to their customers. Maximum customer benefit derives from minimum cost and sufficient supply availability. Customers willing to share in "availability risk" can derive further benefit by participating in controlled outage programs. Specifically, whenever utilities foresee dangerous loading patterns, there is a need for a rapid reduction in demand either system-wide or at specific locations. The utility needs to get relief in order to solve its problems quickly and efficiently. This relief can come from customers who agree to curtail their loads upon request in exchange for an incentive fee. This thesis shows how utilities can get efficient load relief while maximizing their economic benefit. This work also shows how estimated customer cost functions can be calibrated, using existing utility data, to help in designing efficient demand management contracts. In order to design such contracts, optimal mechanism design is adopted from "Game Theory" and applied to the interaction between a utility and its customers. The idea behind mechanism design is to design an incentive structure that encourages customers to sign up for the right contract and reveal their true value of power. If a utility has demand management contracts with customers at critical locations, most operational problems can be solved efficiently. This thesis illustrates how locational attributes of customers incorporated into demand management contract design can have a significant impact in solving system problems. This kind of demand management contracts can also be used by an Independent System Operator (ISO). During times of congestion a loss of economic surplus occurs. When the market is too slow or cannot help relieve congestion, demand management

Operation Optimization in a Smart Micro-Grid in the Presence of Distributed Generation and Demand Response

Directory of Open Access Journals (Sweden)

Yongli Wang

2018-03-01

Full Text Available With the application of distributed generation and the development of smart grid technology, micro-grid, an economic and stable power grid, tends to play an important role in the demand side management. Because micro-grid technology and demand response have been widely applied, what Demand Response actions can realize the economic operation of micro-grid has become an important issue for utilities. In this proposed work, operation optimization modeling for micro-grid is done considering distributed generation, environmental factors and demand response. The main contribution of this model is to optimize the cost in the context of considering demand response and system operation. The presented optimization model can reduce the operation cost of micro-grid without bringing discomfort to the users, thus increasing the consumption of clean energy effectively. Then, to solve this operational optimization problem, genetic algorithm is used to implement objective function and DR scheduling strategy. In addition, to validate the proposed model, it is employed on a smart micro-grid from Tianjin. The obtained numerical results clearly indicate the impact of demand response on economic operation of micro-grid and development of distributed generation. Besides, a sensitivity analysis on the natural gas price is implemented according to the situation of China, and the result shows that the natural gas price has a great influence on the operation cost of the micro-grid and effect of demand response.

Demand-Side Flexibility for Energy Transitions: Ensuring the Competitive Development of Demand Response Options

OpenAIRE

Nursimulu, Anjali; Florin, Marie-Valentine; Vuille, François

2015-01-01

This report provides an overview of the current debates about demand response development, focusing primarily on Europe, with some comparisons to the United States. ‘Demand response’ includes strategies that involve end-use customers adapting or altering their electricity demand in response to grid conditions or market prices. It is viewed as a multi-purpose power-system resource that enhances the energy system’s capacity to cope with increasing demand, rising costs of conventional transmissi...

Hybrid Forecasting Approach Based on GRNN Neural Network and SVR Machine for Electricity Demand Forecasting

Directory of Open Access Journals (Sweden)

Weide Li

2017-01-01

Full Text Available Accurate electric power demand forecasting plays a key role in electricity markets and power systems. The electric power demand is usually a non-linear problem due to various unknown reasons, which make it difficult to get accurate prediction by traditional methods. The purpose of this paper is to propose a novel hybrid forecasting method for managing and scheduling the electricity power. EEMD-SCGRNN-PSVR, the proposed new method, combines ensemble empirical mode decomposition (EEMD, seasonal adjustment (S, cross validation (C, general regression neural network (GRNN and support vector regression machine optimized by the particle swarm optimization algorithm (PSVR. The main idea of EEMD-SCGRNN-PSVR is respectively to forecast waveform and trend component that hidden in demand series to substitute directly forecasting original electric demand. EEMD-SCGRNN-PSVR is used to predict the one week ahead half-hour’s electricity demand in two data sets (New South Wales (NSW and Victorian State (VIC in Australia. Experimental results show that the new hybrid model outperforms the other three models in terms of forecasting accuracy and model robustness.

Modelling transport energy demand: A socio-technical approach

International Nuclear Information System (INIS)

Anable, Jillian; Brand, Christian; Tran, Martino; Eyre, Nick

2012-01-01

Despite an emerging consensus that societal energy consumption and related emissions are not only influenced by technical efficiency but also by lifestyles and socio-cultural factors, few attempts have been made to operationalise these insights in models of energy demand. This paper addresses that gap by presenting a scenario exercise using an integrated suite of sectoral and whole systems models to explore potential energy pathways in the UK transport sector. Techno-economic driven scenarios are contrasted with one in which social change is strongly influenced by concerns about energy use, the environment and well-being. The ‘what if’ Lifestyle scenario reveals a future in which distance travelled by car is reduced by 74% by 2050 and final energy demand from transport is halved compared to the reference case. Despite the more rapid uptake of electric vehicles and the larger share of electricity in final energy demand, it shows a future where electricity decarbonisation could be delayed. The paper illustrates the key trade-off between the more aggressive pursuit of purely technological fixes and demand reduction in the transport sector and concludes there are strong arguments for pursuing both demand and supply side solutions in the pursuit of emissions reduction and energy security.

Demand-side management and European environmental and energy goals: An optimal complementary approach

International Nuclear Information System (INIS)

Bergaentzlé, Claire; Clastres, Cédric; Khalfallah, Haikel

2014-01-01

Demand side management (DSM) in electricity markets could improve energy efficiency and achieve environmental targets through controlled consumption. For the past 10 years or so DSM programmes have registered significant results. However, detailed analysis of its real impact as observed by a large number of pilot studies suggests that such programmes need to be fine-tuned to suit clearly identified conditions. This study aims to provide recommendations for the instruments to be used to prompt demand response with a view to maximizing energy and environmental efficiencies of various countries. The present study suggests that different DSM models should be deployed depending on the specific generation mix in any given country. Beside the natural benefits from cross-borders infrastructures, DSM improves the flexibility and reliability of the energy system, absorbing some shock on generation mix. We show efficiency increases with demand response but at a decreasing rate. So, according to rebound and report effects, simple DSM tools could be preferred. - Highlights: • Demand side management could improve energy and environmental efficiency. • Several instruments should be used to achieve significant load-shedding. • DSM models should be deployed depending on generation mix. • Efficiency increases with demand response but at a decreasing rate. • Rebound and report effects reduce positive impacts

The impact of demand side management strategies in the penetration of renewable electricity

International Nuclear Information System (INIS)

Pina, André; Silva, Carlos; Ferrão, Paulo

2012-01-01

High fuel costs, increasing energy security and concerns with reducing emissions have pushed governments to invest in the use of renewable energies for electricity generation. However, the intermittence of most renewable resources when renewable energy provides a significant share of the energy mix can create problems to electricity grids, which can be minimized by energy storage systems that are usually not available or expensive. An alternative solution consists on the use of demand side management strategies, which can have the double effect of reducing electricity consumption and allowing greater efficiency and flexibility in the grid management, namely by enabling a better match between supply and demand. This work analyzes the impact of demand side management strategies in the evolution of the electricity mix of Flores Island in the Azores archipelago which is characterized by high shares of renewable energy and therefore the introduction of more renewable energy sources makes it an interesting case study for testing innovative solutions. The electricity generation system is modeled in TIMES, a software which optimizes the investment and operation of wind and hydro plants until 2020 based on scenarios for demand growth, deployment of demand response technologies in the domestic sector and promotion of behavioral changes to eliminate standby power. The results show that demand side management strategies can lead to a significant delay in the investment on new generation capacity from renewable resources and improve the operation of the existing installed capacity. -- Highlights: ► Energy efficiency can help reduce the need for investment in more renewable energy. ► Dynamic demand helps increase the use of renewable energy in low demand periods. ► Around 40% of total consumption by domestic appliances is used as dynamic demand. ► The load of domestic appliances is mainly shifted to the 5:00 to 9:00 period.

Characterising Wildlife Trade Market Supply-Demand Dynamics

Science.gov (United States)

Rowcliffe, M.; Cowlishaw, G.; Alexander, J. S.; Ntiamoa-Baidu, Y.; Brenya, A.; Milner-Gulland, E. J.

2016-01-01

The trade in wildlife products can represent an important source of income for poor people, but also threaten wildlife locally, regionally and internationally. Bushmeat provides livelihoods for hunters, traders and sellers, protein to rural and urban consumers, and has depleted the populations of many tropical forest species. Management interventions can be targeted towards the consumers or suppliers of wildlife products. There has been a general assumption in the bushmeat literature that the urban trade is driven by consumer demand with hunters simply fulfilling this demand. Using the urban bushmeat trade in the city of Kumasi, Ghana, as a case study, we use a range of datasets to explore the processes driving the urban bushmeat trade. We characterise the nature of supply and demand by explicitly considering three market attributes: resource condition, hunter behaviour, and consumer behaviour. Our results suggest that bushmeat resources around Kumasi are becoming increasingly depleted and are unable to meet demand, that hunters move in and out of the trade independently of price signals generated by the market, and that, for the Kumasi bushmeat system, consumption levels are driven not by consumer choice but by shortfalls in supply and consequent price responses. Together, these results indicate that supply-side processes dominate the urban bushmeat trade in Kumasi. This suggests that future management interventions should focus on changing hunter behaviour, although complementary interventions targeting consumer demand are also likely to be necessary in the long term. Our approach represents a structured and repeatable method to assessing market dynamics in information-poor systems. The findings serve as a caution against assuming that wildlife markets are demand driven, and highlight the value of characterising market dynamics to inform appropriate management. PMID:27632169

Imperfect price-reversibility of US gasoline demand: Asymmetric responses to price increases and declines

International Nuclear Information System (INIS)

Gately, D.

1992-01-01

This paper describes a framework for analyzing the imperfect price-reversibility (hysteresis) of oil demand. The oil demand reductions following the oil price increases of the 1970s will not be completely reversed by the price cuts of the 1980s, nor is it necessarily true that these partial demand reversals themselves will be reversed exactly by future price increases. The author decomposes price into three monotonic series: price increases to maximum historic levels, price cuts, and price recoveries (increases below historic highs). He would expect that the response to price cuts would be no greater than to price recoveries, which in turn would be no greater than for increases in maximum historic price. For evidence of imperfect price-reversibility, he tests econometrically the following US data: vehicle miles per driver, the fuel efficiency of the automobile fleet, and gasoline demand per driver. In each case, the econometric results allow him to reject the hypothesis of perfect price-reversibility. The data show smaller response to price cuts than to price increases. This has dramatic implications for projections of gasoline and oil demand, especially under low-price assumptions. 26 refs., 13 figs., 3 tabs

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

Science.gov (United States)

Wu, Qi

2010-03-01

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

Energy demand in Portuguese manufacturing: a two-stage model

International Nuclear Information System (INIS)

Borges, A.M.; Pereira, A.M.

1992-01-01

We use a two-stage model of factor demand to estimate the parameters determining energy demand in Portuguese manufacturing. In the first stage, a capital-labor-energy-materials framework is used to analyze the substitutability between energy as a whole and other factors of production. In the second stage, total energy demand is decomposed into oil, coal and electricity demands. The two stages are fully integrated since the energy composite used in the first stage and its price are obtained from the second stage energy sub-model. The estimates obtained indicate that energy demand in manufacturing responds significantly to price changes. In addition, estimation results suggest that there are important substitution possibilities among energy forms and between energy and other factors of production. The role of price changes in energy-demand forecasting, as well as in energy policy in general, is clearly established. (author)

Does Knowledge Contribute to the Acceptance of Demand Response?

Directory of Open Access Journals (Sweden)

Salla Annala

2014-03-01

Full Text Available More flexible demand side would benefit the electricity markets, networks and sustainable power generation in many ways. The success of demand response programs, however, relies on consumer acceptance. This paper reviews previous studies about acceptability of different kinds of residential demand response programs. Furthermore, it discusses whether consumers who are more aware of the principles and benefits of demand response have more positive attitudes towards demand response programs. The results of the literature review and two survey studies suggest that price and security of supply are currently bigger motives to change consumption behaviour than environmental issues and that the savings expected to trigger any action (and to lead to lasting change in behaviour may be relatively high. Therefore, the framing of demand response programs goals may affect the acceptance. Additionally, consumers seem to prefer simple price structures that remain constant for a long time to more dynamic options.

Auction-Based Cloud Service Pricing and Penalty with Availability on Demand

Directory of Open Access Journals (Sweden)

Xiaohong Wu

2018-04-01

Full Text Available Availability is one of the main concerns of cloud users, and cloud providers always try to provide higher availability to improve user satisfaction. However, higher availability results in higher provider costs and lower social welfare. In this paper, taking into account both the users’ valuation and desired availability, we design resource allocation, pricing and penalty mechanisms with availability on demand. Considering two scenarios: public availability in which the desired availabilities of all users are public information, and private availability in which the desired availabilities are private information of users, and, analyzing the possible behaviours of users, we design a truthful deterministic mechanism with 2-approximation in public availability scenario and a universal truthful mechanism with 1 1 + γ approximation in private availability scenario, where γ is the backup ratio of resources with the highest availability. The experiment results show that our mechanisms significantly improve the social welfare compared to the mechanism without considering availability demand of users.

1993 US petroleum engineering manpower supply and demand

International Nuclear Information System (INIS)

Wattenbarger, R.A.; Morriss, S.

1994-01-01

Each year, the SPE Manpower Committee reports on the results of petroleum engineering manpower supply and demand surveys to inform SPE members about hiring patterns of engineers in the petroleum industry and the supply of graduates from US petroleum engineering schools. The SPE Manpower Committee's US surveys show that large companies will decrease their hiring while small companies and service companies will increase their hiring of engineers. During 1992--93, only about 65% of graduating petroleum engineering students were known to have jobs. Another finding is that, overall, new US SPE membership is decreasing while non-US membership is increasing

Opportunities for Automated Demand Response in California Wastewater Treatment Facilities

Energy Technology Data Exchange (ETDEWEB)

Aghajanzadeh, Arian [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Wray, Craig [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); McKane, Aimee [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2015-08-30

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 process 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.

An economic approach to abortion demand.

Science.gov (United States)

Rothstein, D S

1992-01-01

"This paper uses econometric multiple regression techniques in order to analyze the socioeconomic factors affecting the demand for abortion for the year 1985. A cross-section of the 50 [U.S.] states and Washington D.C. is examined and a household choice theoretical framework is utilized. The results suggest that average price of abortion, disposable personal per capita income, percentage of single women, whether abortions are state funded, unemployment rate, divorce rate, and if the state is located in the far West, are statistically significant factors in the determination of the demand for abortion." excerpt

DEMAND FOR MALAYSIA'S EXPORTS: EVIDENCE FROM THE ELECTRONICS INDUSTRY

OpenAIRE

Koi Nyen Wong

2006-01-01

This study estimates the determinants of foreign demand for Malaysia's top five electronics exports by SITC (Standard International Trade Classification) product groups from 1990 to 2001. Cointegration results indicate a unique long-run relationship between export demand for electronic products and relative prices and foreign income. Both the estimated long-run income and price elasticities of export demand are greater than 1, conforming to a pattern found in most fast-growing economies and i...

Demand-Withdraw Patterns in Marital Conflict in the Home

OpenAIRE

Papp, Lauren M.; Kouros, Chrystyna D.; Cummings, E. Mark

2009-01-01