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Sample records for based day-ahead self-scheduling

  1. Hybrid Particle Swarm Optimization based Day-Ahead Self-Scheduling for Thermal Generator in Competitive Electricity Market

    DEFF Research Database (Denmark)

    Pindoriya, Naran M.; Singh, S.N.; Østergaard, Jacob

    2009-01-01

    in day-ahead energy market subject to operational constraints and 2) at the same time, to minimize the risk due to uncertainty in price forecast. Therefore, it is a conflicting bi-objective optimization problem which has both binary and continuous optimization variables considered as constrained mixed......This paper presents a hybrid particle swarm optimization algorithm (HPSO) to solve the day-ahead self-scheduling for thermal power producer in competitive electricity market. The objective functions considered to model the self-scheduling problem are 1) to maximize the profit from selling energy...... integer nonlinear programming. To demonstrate the effectiveness of the proposed method for self-scheduling in a day-ahead energy market, the locational margin price (LMP) forecast uncertainty in PJM electricity market is considered. An adaptive wavelet neural network (AWNN) is used to forecast the day...

  2. Day-Ahead Self-Scheduling of Thermal Generator in Competitive Electricity Market Using Hybrid PSO

    DEFF Research Database (Denmark)

    Pindoriya, N.M.; Singh, Sri Niwas; Østergaard, Jacob

    2009-01-01

    in day-ahead energy market subject to operational constraints and 2) at the same time, to minimize the risk due to uncertainty in price forecast. Therefore, it is a conflicting biobjective optimization problem which has both binary and continuous optimization variables considered as constrained mixed......This paper presents a hybrid particle swarm optimization algorithm (HPSO) to solve the day-ahead selfscheduling for thermal power producer in competitive electricity market. The objective functions considered to model the selfscheduling problem are: 1) to maximize the profit from selling energy...... integer nonlinear programming. To demonstrate the effectiveness of the proposed method for self-scheduling in a dayahead energy market, the locational margin price (LMP) forecast uncertainty in PJM electricity market is considered. An adaptive wavelet neural network (AWNN) is used to forecast the dayahead...

  3. Hydrothermal self-scheduling problem in a day-ahead electricity market

    International Nuclear Information System (INIS)

    This paper addresses the self-scheduling problem of determining the unit commitment status for power generation companies before submitting the hourly bids in a day-ahead market. The hydrothermal model is formulated as a deterministic optimization problem where expected profit is maximized using the 0/1 mixed-integer linear programming technique. This approach allows precise modelling of non-convex variable cost functions and non-linear start-up cost functions of thermal units, non-concave power-discharge characteristics of hydro units, ramp rate limits of thermal units and minimum up and down time constraints for both hydro and thermal units. Model incorporates long-term bilateral contracts with contracted power and price patterns, as well as forecasted market hourly prices for day-ahead auction. Solution is achieved using the homogeneous interior point method for linear programming as state of the art technique, with a branch and bound optimizer for integer programming. The effectiveness of the proposed model in optimizing the generation schedule is demonstrated through the case studies and their analysis. (author)

  4. Security-constrained self-scheduling of generation companies in day-ahead electricity markets considering financial risk

    International Nuclear Information System (INIS)

    Highlights: ► A security-constrained self-scheduling is presented. ► The proposed framework takes into account the uncertainty of the predicted market prices. ► We model the risk and profit tradeoff of a GENCO based on an efficient multi-objective model. ► Unit commitment and inter-temporal constraints of generators are considered in an MIP model. ► Simulation results are presented on the IEEE 30-bus and IEEE 118-bus test systems. - Abstract: In this paper, a new security-constrained self-scheduling framework incorporating the transmission flow limits in both steady state conditions and post-contingent states is presented to produce efficient bidding strategy for generation companies (GENCOs) in day-ahead electricity markets. Moreover, the proposed framework takes into account the uncertainty of the predicted market prices and models the risk and profit tradeoff of a GENCO based on an efficient multi-objective model. Furthermore, unit commitment and inter-temporal constraints of generators are considered in the suggested model converting it to a mixed-integer programming (MIP) optimization problem. Sensitivity of the proposed framework with respect to both the level of the market prices and adopted risk level is also evaluated in the paper. Simulation results are presented on the IEEE 30-bus and IEEE 118-bus test systems illustrating the performance of the proposed self-scheduling model.

  5. A Convex Model of Risk-Based Unit Commitment for Day-Ahead Market Clearing Considering Wind Power Uncertainty

    DEFF Research Database (Denmark)

    Zhang, Ning; Kang, Chongqing; Xia, Qing;

    2015-01-01

    presents a novel risk-based day-ahead unit commitment (RUC) model that considers the risks of the loss of load, wind curtailment and branch overflow caused by wind power uncertainty. These risks are formulated in detail using the probabilistic distributions of wind power probabilistic forecast...... that the risk modeling facilitates a strategic market clearing procedure with a reasonable computational expense....

  6. Incentive-based demand response programs designed by asset-light retail electricity providers for the day-ahead market

    International Nuclear Information System (INIS)

    Following the deregulation experience of retail electricity markets in most countries, the majority of the new entrants of the liberalized retail market were pure REP (retail electricity providers). These entities were subject to financial risks because of the unexpected price variations, price spikes, volatile loads and the potential for market power exertion by GENCO (generation companies). A REP can manage the market risks by employing the DR (demand response) programs and using its' generation and storage assets at the distribution network to serve the customers. The proposed model suggests how a REP with light physical assets, such as DG (distributed generation) units and ESS (energy storage systems), can survive in a competitive retail market. The paper discusses the effective risk management strategies for the REPs to deal with the uncertainties of the DAM (day-ahead market) and how to hedge the financial losses in the market. A two-stage stochastic programming problem is formulated. It aims to establish the financial incentive-based DR programs and the optimal dispatch of the DG units and ESSs. The uncertainty of the forecasted day-ahead load demand and electricity price is also taken into account with a scenario-based approach. The principal advantage of this model for REPs is reducing the risk of financial losses in DAMs, and the main benefit for the whole system is market power mitigation by virtually increasing the price elasticity of demand and reducing the peak demand. - Highlights: • Asset-light electricity retail providers subject to financial risks. • Incentive-based demand response program to manage the financial risks. • Maximizing the payoff of electricity retail providers in day-ahead market. • Mixed integer nonlinear programming to manage the risks

  7. Day-ahead electricity prices forecasting by a modified CGSA technique and hybrid WT in LSSVM based scheme

    International Nuclear Information System (INIS)

    Highlights: • Presenting a hybrid CGSA-LSSVM scheme for price forecasting. • Considering uncertainties for filtering in input data and feature selection to improve efficiency. • Using DWT input featured LSSVM approach to classify next-week prices. • Used three real markets to illustrate performance of the proposed price forecasting model. - Abstract: At the present time, day-ahead electricity market is closely associated with other commodity markets such as fuel market and emission market. Under such an environment, day-ahead electricity price forecasting has become necessary for power producers and consumers in the current deregulated electricity markets. Seeking for more accurate price forecasting techniques, this paper proposes a new combination of a Feature Selection (FS) technique based mutual information (MI) technique and Wavelet Transform (WT) in this study. Moreover, in this paper a new modified version of Gravitational Search Algorithm (GSA) optimization based chaos theory, namely Chaotic Gravitational Search Algorithm (CGSA) is developed to find the optimal parameters of Least Square Support Vector Machine (LSSVM) to predict electricity prices. The performance and price forecast accuracy of the proposed technique is assessed by means of real data from Iran’s, Ontario’s and Spain’s price markets. The simulation results from numerical tables and figures in different cases show that the proposed technique increases electricity price market forecasting accuracy than the other classical and heretical methods in the scientific researches

  8. Day-ahead crude oil price forecasting using a novel morphological component analysis based model.

    Science.gov (United States)

    Zhu, Qing; He, Kaijian; Zou, Yingchao; Lai, Kin Keung

    2014-01-01

    As a typical nonlinear and dynamic system, the crude oil price movement is difficult to predict and its accurate forecasting remains the subject of intense research activity. Recent empirical evidence suggests that the multiscale data characteristics in the price movement are another important stylized fact. The incorporation of mixture of data characteristics in the time scale domain during the modelling process can lead to significant performance improvement. This paper proposes a novel morphological component analysis based hybrid methodology for modeling the multiscale heterogeneous characteristics of the price movement in the crude oil markets. Empirical studies in two representative benchmark crude oil markets reveal the existence of multiscale heterogeneous microdata structure. The significant performance improvement of the proposed algorithm incorporating the heterogeneous data characteristics, against benchmark random walk, ARMA, and SVR models, is also attributed to the innovative methodology proposed to incorporate this important stylized fact during the modelling process. Meanwhile, work in this paper offers additional insights into the heterogeneous market microstructure with economic viable interpretations.

  9. A Modified Feature Selection and Artificial Neural Network-Based Day-Ahead Load Forecasting Model for a Smart Grid

    Directory of Open Access Journals (Sweden)

    Ashfaq Ahmad

    2015-12-01

    Full Text Available In the operation of a smart grid (SG, day-ahead load forecasting (DLF is an important task. The SG can enhance the management of its conventional and renewable resources with a more accurate DLF model. However, DLF model development is highly challenging due to the non-linear characteristics of load time series in SGs. In the literature, DLF models do exist; however, these models trade off between execution time and forecast accuracy. The newly-proposed DLF model will be able to accurately predict the load of the next day with a fair enough execution time. Our proposed model consists of three modules; the data preparation module, feature selection and the forecast module. The first module makes the historical load curve compatible with the feature selection module. The second module removes redundant and irrelevant features from the input data. The third module, which consists of an artificial neural network (ANN, predicts future load on the basis of selected features. Moreover, the forecast module uses a sigmoid function for activation and a multi-variate auto-regressive model for weight updating during the training process. Simulations are conducted in MATLAB to validate the performance of our newly-proposed DLF model in terms of accuracy and execution time. Results show that our proposed modified feature selection and modified ANN (m(FS + ANN-based model for SGs is able to capture the non-linearity(ies in the history load curve with 97 . 11 % accuracy. Moreover, this accuracy is achieved at the cost of a fair enough execution time, i.e., we have decreased the average execution time of the existing FS + ANN-based model by 38 . 50 % .

  10. Incentive-based demand response programs designed by asset-light retail electricity providers for the day-ahead market

    DEFF Research Database (Denmark)

    Fotouhi Ghazvini, Mohammad Ali; Faria, Pedro; Ramos, Sergio;

    2015-01-01

    Following the deregulation experience of retail electricity markets in most countries, the majority of the new entrants of the liberalized retail market were pure REP (retail electricity providers). These entities were subject to financial risks because of the unexpected price variations, price...... spikes, volatile loads and the potential for market power exertion by GENCO (generation companies). A REP can manage the market risks by employing the DR (demand response) programs and using its' generation and storage assets at the distribution network to serve the customers. The proposed model suggests...... how a REP with light physical assets, such as DG (distributed generation) units and ESS (energy storage systems), can survive in a competitive retail market. The paper discusses the effective risk management strategies for the REPs to deal with the uncertainties of the DAM (day-ahead market) and how...

  11. A new approach for GenCos profit based unit commitment in day-ahead competitive electricity markets considering reserve uncertainty

    International Nuclear Information System (INIS)

    This paper presents a new approach for GenCos Profit Based Unit Commitment (GPBUC) in day-ahead competitive electricity markets. Generation, spinning and non-spinning reserves are considered in the proposed formulation. The estimated probability that spinning and non-spinning reserves are called and generated is also considered in the formulation to simulate the reserve uncertainty. The artificial neural network (ANN) is applied for forecasting the reserve probability considering line limits, line and generator outages, market prices, bidding strategy, load and reserves patterns. Fuel and emission constraints are included in the model. A hybrid method between Lagrangian relaxation (LR) and evolutionary programming (EP) is applied to solve the proposed GPBUC problem. The proposed approach is applied to a 36 unit test system and the results are compared with those obtained from other approaches. (author)

  12. Finding diversity for building one-day ahead Hydrological Ensemble Prediction System based on artificial neural network stacks

    Science.gov (United States)

    Brochero, Darwin; Anctil, Francois; Gagné, Christian; López, Karol

    2013-04-01

    In this study, we addressed the application of Artificial Neural Networks (ANN) in the context of Hydrological Ensemble Prediction Systems (HEPS). Such systems have become popular in the past years as a tool to include the forecast uncertainty in the decision making process. HEPS considers fundamentally the uncertainty cascade model [4] for uncertainty representation. Analogously, the machine learning community has proposed models of multiple classifier systems that take into account the variability in datasets, input space, model structures, and parametric configuration [3]. This approach is based primarily on the well-known "no free lunch theorem" [1]. Consequently, we propose a framework based on two separate but complementary topics: data stratification and input variable selection (IVS). Thus, we promote an ANN prediction stack in which each predictor is trained based on input spaces defined by the IVS application on different stratified sub-samples. All this, added to the inherent variability of classical ANN optimization, leads us to our ultimate goal: diversity in the prediction, defined as the complementarity of the individual predictors. The stratification application on the 12 basins used in this study, which originate from the second and third workshop of the MOPEX project [2], shows that the informativeness of the data is far more important than the quantity used for ANN training. Additionally, the input space variability leads to ANN stacks that outperform an ANN stack model trained with 100% of the available information but with a random selection of dataset used in the early stopping method (scenario R100P). The results show that from a deterministic view, the main advantage focuses on the efficient selection of the training information, which is an equally important concept for the calibration of conceptual hydrological models. On the other hand, the diversity achieved is reflected in a substantial improvement in the scores that define the

  13. A Comparison of the Performance of Advanced Statistical Techniques for the Refinement of Day-ahead and Longer NWP-based Wind Power Forecasts

    Science.gov (United States)

    Zack, J. W.

    2015-12-01

    Predictions from Numerical Weather Prediction (NWP) models are the foundation for wind power forecasts for day-ahead and longer forecast horizons. The NWP models directly produce three-dimensional wind forecasts on their respective computational grids. These can be interpolated to the location and time of interest. However, these direct predictions typically contain significant systematic errors ("biases"). This is due to a variety of factors including the limited space-time resolution of the NWP models and shortcomings in the model's representation of physical processes. It has become common practice to attempt to improve the raw NWP forecasts by statistically adjusting them through a procedure that is widely known as Model Output Statistics (MOS). The challenge is to identify complex patterns of systematic errors and then use this knowledge to adjust the NWP predictions. The MOS-based improvements are the basis for much of the value added by commercial wind power forecast providers. There are an enormous number of statistical approaches that can be used to generate the MOS adjustments to the raw NWP forecasts. In order to obtain insight into the potential value of some of the newer and more sophisticated statistical techniques often referred to as "machine learning methods" a MOS-method comparison experiment has been performed for wind power generation facilities in 6 wind resource areas of California. The underlying NWP models that provided the raw forecasts were the two primary operational models of the US National Weather Service: the GFS and NAM models. The focus was on 1- and 2-day ahead forecasts of the hourly wind-based generation. The statistical methods evaluated included: (1) screening multiple linear regression, which served as a baseline method, (2) artificial neural networks, (3) a decision-tree approach called random forests, (4) gradient boosted regression based upon an decision-tree algorithm, (5) support vector regression and (6) analog ensemble

  14. Robust Optimization-Based Generation Self-Scheduling under Uncertain Price

    Directory of Open Access Journals (Sweden)

    Xiao Luo

    2011-01-01

    Full Text Available This paper considers generation self-scheduling in electricity markets under uncertain price. Based on the robust optimization (denoted as RO methodology, a new self-scheduling model, which has a complicated max-min optimization structure, is set up. By using optimal dual theory, the proposed model is reformulated to an ordinary quadratic and quadratic cone programming problems in the cases of box and ellipsoidal uncertainty, respectively. IEEE 30-bus system is used to test the new model. Some comparisons with other methods are done, and the sensitivity with respect to the uncertain set is analyzed. Comparing with the existed uncertain self-scheduling approaches, the new method has twofold characteristics. First, it does not need a prediction of distribution of random variables and just requires an estimated value and the uncertain set of power price. Second, the counterpart of RO corresponding to the self-scheduling is a simple quadratic or quadratic cone programming. This indicates that the reformulated problem can be solved by many ordinary optimization algorithms.

  15. One-day-ahead streamflow forecasting via super-ensembles of several neural network architectures based on the Multi-Level Diversity Model

    Science.gov (United States)

    Brochero, Darwin; Hajji, Islem; Pina, Jasson; Plana, Queralt; Sylvain, Jean-Daniel; Vergeynst, Jenna; Anctil, Francois

    2015-04-01

    Theories about generalization error with ensembles are mainly based on the diversity concept, which promotes resorting to many members of different properties to support mutually agreeable decisions. Kuncheva (2004) proposed the Multi Level Diversity Model (MLDM) to promote diversity in model ensembles, combining different data subsets, input subsets, models, parameters, and including a combiner level in order to optimize the final ensemble. This work tests the hypothesis about the minimisation of the generalization error with ensembles of Neural Network (NN) structures. We used the MLDM to evaluate two different scenarios: (i) ensembles from a same NN architecture, and (ii) a super-ensemble built by a combination of sub-ensembles of many NN architectures. The time series used correspond to the 12 basins of the MOdel Parameter Estimation eXperiment (MOPEX) project that were used by Duan et al. (2006) and Vos (2013) as benchmark. Six architectures are evaluated: FeedForward NN (FFNN) trained with the Levenberg Marquardt algorithm (Hagan et al., 1996), FFNN trained with SCE (Duan et al., 1993), Recurrent NN trained with a complex method (Weins et al., 2008), Dynamic NARX NN (Leontaritis and Billings, 1985), Echo State Network (ESN), and leak integrator neuron (L-ESN) (Lukosevicius and Jaeger, 2009). Each architecture performs separately an Input Variable Selection (IVS) according to a forward stepwise selection (Anctil et al., 2009) using mean square error as objective function. Post-processing by Predictor Stepwise Selection (PSS) of the super-ensemble has been done following the method proposed by Brochero et al. (2011). IVS results showed that the lagged stream flow, lagged precipitation, and Standardized Precipitation Index (SPI) (McKee et al., 1993) were the most relevant variables. They were respectively selected as one of the firsts three selected variables in 66, 45, and 28 of the 72 scenarios. A relationship between aridity index (Arora, 2002) and NN

  16. Hourly Electricity Prices in Day-Ahead Markets

    NARCIS (Netherlands)

    R. Huisman (Ronald); C. Huurman; R.J. Mahieu (Ronald)

    2007-01-01

    textabstractThis paper focuses on the characteristics of hourly electricity prices in day-ahead markets. In these markets, quotes for day-ahead delivery of electricity are submitted simultaneously for all hours in the next day. The same information set is used for quoting all hours of the day. The d

  17. Support vector machine for day ahead electricity price forecasting

    Science.gov (United States)

    Razak, Intan Azmira binti Wan Abdul; Abidin, Izham bin Zainal; Siah, Yap Keem; Rahman, Titik Khawa binti Abdul; Lada, M. Y.; Ramani, Anis Niza binti; Nasir, M. N. M.; Ahmad, Arfah binti

    2015-05-01

    Electricity price forecasting has become an important part of power system operation and planning. In a pool- based electric energy market, producers submit selling bids consisting in energy blocks and their corresponding minimum selling prices to the market operator. Meanwhile, consumers submit buying bids consisting in energy blocks and their corresponding maximum buying prices to the market operator. Hence, both producers and consumers use day ahead price forecasts to derive their respective bidding strategies to the electricity market yet reduce the cost of electricity. However, forecasting electricity prices is a complex task because price series is a non-stationary and highly volatile series. Many factors cause for price spikes such as volatility in load and fuel price as well as power import to and export from outside the market through long term contract. This paper introduces an approach of machine learning algorithm for day ahead electricity price forecasting with Least Square Support Vector Machine (LS-SVM). Previous day data of Hourly Ontario Electricity Price (HOEP), generation's price and demand from Ontario power market are used as the inputs for training data. The simulation is held using LSSVMlab in Matlab with the training and testing data of 2004. SVM that widely used for classification and regression has great generalization ability with structured risk minimization principle rather than empirical risk minimization. Moreover, same parameter settings in trained SVM give same results that absolutely reduce simulation process compared to other techniques such as neural network and time series. The mean absolute percentage error (MAPE) for the proposed model shows that SVM performs well compared to neural network.

  18. What day-ahead reserves are needed in electric grids with high levels of wind power?

    Science.gov (United States)

    Mauch, Brandon; Apt, Jay; Carvalho, Pedro M. S.; Jaramillo, Paulina

    2013-09-01

    Day-ahead load and wind power forecasts provide useful information for operational decision making, but they are imperfect and forecast errors must be offset with operational reserves and balancing of (real time) energy. Procurement of these reserves is of great operational and financial importance in integrating large-scale wind power. We present a probabilistic method to determine net load forecast uncertainty for day-ahead wind and load forecasts. Our analysis uses data from two different electric grids in the US with similar levels of installed wind capacity but with large differences in wind and load forecast accuracy, due to geographic characteristics. We demonstrate that the day-ahead capacity requirements can be computed based on forecasts of wind and load. For 95% day-ahead reliability, this required capacity ranges from 2100 to 5700 MW for ERCOT, and 1900 to 4500 MW for MISO (with 10 GW of installed wind capacity), depending on the wind and load forecast values. We also show that for each MW of additional wind power capacity for ERCOT, 0.16-0.30 MW of dispatchable capacity will be used to compensate for wind uncertainty based on day-ahead forecasts. For MISO (with its more accurate forecasts), the requirement is 0.07-0.13 MW of dispatchable capacity for each MW of additional wind capacity.

  19. What day-ahead reserves are needed in electric grids with high levels of wind power?

    International Nuclear Information System (INIS)

    Day-ahead load and wind power forecasts provide useful information for operational decision making, but they are imperfect and forecast errors must be offset with operational reserves and balancing of (real time) energy. Procurement of these reserves is of great operational and financial importance in integrating large-scale wind power. We present a probabilistic method to determine net load forecast uncertainty for day-ahead wind and load forecasts. Our analysis uses data from two different electric grids in the US with similar levels of installed wind capacity but with large differences in wind and load forecast accuracy, due to geographic characteristics. We demonstrate that the day-ahead capacity requirements can be computed based on forecasts of wind and load. For 95% day-ahead reliability, this required capacity ranges from 2100 to 5700 MW for ERCOT, and 1900 to 4500 MW for MISO (with 10 GW of installed wind capacity), depending on the wind and load forecast values. We also show that for each MW of additional wind power capacity for ERCOT, 0.16–0.30 MW of dispatchable capacity will be used to compensate for wind uncertainty based on day-ahead forecasts. For MISO (with its more accurate forecasts), the requirement is 0.07–0.13 MW of dispatchable capacity for each MW of additional wind capacity. (letter)

  20. Chance-Constrained Programming Based Day-Ahead Optimal Scheduling of Energy Storage%基于机会约束规划的储能日前优化调度

    Institute of Scientific and Technical Information of China (English)

    赵书强; 刘晨亮; 王明雨; 胡永强

    2013-01-01

    To make the output of the hybrid wind/photovoltaic/energy storage system farthest matched with the scheduled output, the method of one-day ahead optimized control of energy storage equipments is adopted. In view of the randomness of PV generation and wind power generation, a chance-constrained programming based optimal control method of energy storage, in which the constraint of power output of energy storage equipments and the constraint of electric quantity are taken into account and the maximum similarity between the total output curve of hybrid wind/photovoltaic/energy storage system and the given scheduled output curve is taken as the objective function, is proposed and solved by stochastic simulation based particle swarm optimization, thus the charging/discharging power of energy storage equipments corresponding to condition that the two curves are most oncoming is obtained. Analysis on results of calculation example shows that the proposed optimized control strategy of energy storage equipments can make the total output of hybrid wind/photovoltaic/energy storage system farthest tracing the scheduled output curve.%为了最大程度地使风光储联合发电系统的出力与计划出力相匹配,采用提前一天对储能装置进行优化控制的方法。因风光出力具有随机性,提出了基于机会约束规划的储能优化控制方法。该方法考虑了储能装置的功率出力和电量约束条件,以风光储总出力曲线与给定的计划出力曲线的相似度最大为目标函数,使用基于随机模拟的粒子群算法求解,得到两条曲线最接近时对应的储能充放电功率。算例分析结果表明,所提出的储能优化控制策略能够使风光储联合发电系统总出力最大程度地跟踪计划出力曲线。

  1. Powernext Day-AheadTM products and market organization

    International Nuclear Information System (INIS)

    The introduction of a power exchange in France is a direct response to the opening up of the European electricity markets. Powernext SA is a Multilateral Trading Facility in charge of managing the French power exchange through an optional and anonymous organised exchange offering: - Day-ahead contracts for the management of volume risk on Powernext Day-AheadTM since 21 November 2001, - Medium term contracts for the management of price risk on Powernext FuturesTM since 18 June 2004. This document presents the principle of the trading of hourly contracts on Powernext Day-AheadTM, the accessibility of the market, the SAPRI trading platform operated by Nord Pool, the Scandinavian power exchange, the validation of the auction results, the collaboration with LCH.Clearnet SA to secure and facilitate the transactions, and the delivery guarantee implemented by RTE (the French energy transport network). (J.S.)

  2. Feedback, competition and stochasticity in a day ahead electricity market

    International Nuclear Information System (INIS)

    Major recent changes in electricity markets relate to the process for their deregulation, along with increasing participation of renewable (stochastic) generation e.g. wind power. Our general objective is to model how feedback, competition and stochasticity (on the production side) interact in electricity markets, and eventually assess what their effects are on both the participants and the society. For this, day ahead electricity markets are modeled as dynamic closed loop systems, in which the feedback signal is the market price. In parallel, the Cournot competition model is considered. Mixed portfolios with significant share of renewable energy are based on stochastic threshold cost functions. Regarding trading strategies, it is assumed that generators are looking at optimizing their individual profits. The point of view of the society is addressed by analyzing market behavior and stability. The performed simulations show the beneficial effects of employing long term bidding strategies for both generators and society. Sensitivity analyses are performed in order to evaluate the effects of demand elasticity. It is shown that increase in demand elasticity reduces the possibility for the generators to exploit their market power. Furthermore, the results suggest that introduction of wind power generation in the market is beneficial both for the generators and the society.

  3. Feedback, competition and stochasticity in a day ahead electricity market

    International Nuclear Information System (INIS)

    Major recent changes in electricity markets relate to the process for their deregulation, along with increasing participation of renewable (stochastic) generation e.g. wind power. Our general objective is to model how feedback, competition and stochasticity (on the production side) interact in electricity markets, and eventually assess what their effects are on both the participants and the society. For this, day ahead electricity markets are modeled as dynamic closed loop systems, in which the feedback signal is the market price. In parallel, the Cournot competition model is considered. Mixed portfolios with significant share of renewable energy are based on stochastic threshold cost functions. Regarding trading strategies, it is assumed that generators are looking at optimizing their individual profits. The point of view of the society is addressed by analyzing market behavior and stability. The performed simulations show the beneficial effects of employing long term bidding strategies for both generators and society. Sensitivity analyses are performed in order to evaluate the effects of demand elasticity. It is shown that increase in demand elasticity reduces the possibility for the generators to exploit their market power. Furthermore, the results suggest that introduction of wind power generation in the market is beneficial both for the generators and the society. (author)

  4. A dynamic day-ahead paratransit planning problem

    NARCIS (Netherlands)

    Cremers, Marloes; Klein Haneveld, Wim; van der Vlerk, Maarten

    2007-01-01

    We consider a dynamic planning problem for the transport of elderlyand disabled people. The focus is on a decision to make one day ahead:which requests to serve with own vehicles, and which ones to assign tosubcontractors, under uncertainty of late requests which are gradually revealedduring the day

  5. A dynamic day-ahead paratransit planning problem

    NARCIS (Netherlands)

    Cremers, M.L.A.G.; Klein Haneveld, W.K.; van der Vlerk, M.H.

    2010-01-01

    We consider a dynamic planning problem for the transport of elderly and disabled people. The focus is on a decision to make one day ahead: which requests to serve with own vehicles and which ones to assign to subcontractors under uncertainty of late requests that are gradually revealed during the da

  6. Optimal operation and forecasting policy for pump storage plants in day-ahead markets

    International Nuclear Information System (INIS)

    Highlights: • We investigate unit commitment deploying stochastic and deterministic approaches. • We consider day-ahead markets, its forecast and weekly price based unit commitment. • Stochastic and deterministic unit commitment are identical for the first planning day. • Unit commitment and bidding policy can be based on the deterministic approach. • Robust forecasting models should be estimated based on the whole planning horizon. - Abstract: Pump storage plants are an important electricity storage technology at present. Investments in this technology are expected to increase. The necessary investment valuation often includes expected cash flows from future price-based unit commitment policies. A price-based unit commitment policy has to consider market price uncertainty and the information revealing nature of electricity markets. For this environment stochastic programming models are suggested to derive the optimal unit commitment policy. For the considered day-ahead price electricity market stochastic and deterministic unit commitment policies are comparable suggesting an application of easier implementable deterministic models. In order to identify suitable unit commitment and forecasting policies, deterministic unit commitment models are applied to actual day-ahead electricity prices of a whole year. As a result, a robust forecasting model should consider the unit commitment planning period. This robust forecasting models result in expected cash flows similar to realized ones allowing a reliable investment valuation

  7. Comparative analysis of features of Polish and Lithuanian Day-ahead electricity market prices

    International Nuclear Information System (INIS)

    The goal of this article is to better understand the processes of electricity market price formation in Poland and Lithuania through an analysis of the features (volatility and spikes) of Lithuanian and Polish day-ahead electricity market prices and to assess how acquired electricity price features could affect the achievement of the main goals of the national energy policy. The following indicators have been calculated to determine electricity market price volatility: the oscillation coefficient, the coefficient of variation, an adjusted coefficient of variation, the standard deviation indicator, the daily velocity indicator (based on the overall average price) and the daily velocity indicator (based on the daily average price). Critical values for electricity market price have been calculated to evaluate price spikes. This analysis reveals that electricity market-price volatility is moderate in Poland and high in Lithuania. Electricity price spikes have been an observable phenomenon both in Lithuanian and in Polish day-ahead electricity markets, but they are more common in Lithuania, encompassing 3.15% of the time period analysed in Poland and 4.68% of the time period analysed in Lithuania. Volatile, spiking and increasing electricity prices in day-ahead electricity markets in Lithuania and Poland create preconditions and substantiate the relevance of implementation of the national energy policies and measures. - Highlights: • Moderate and seasonal volatility. spiking market price and. • stable average price

  8. Forecasting Nord Pool day-ahead prices with an autoregressive model

    International Nuclear Information System (INIS)

    This paper presents a model to forecast Nord Pool hourly day-ahead prices. The model is based on but reduced in terms of estimation parameters (from 24 sets to 1) and modified to include Nordic demand and Danish wind power as exogenous variables. We model prices across all hours in the analysis period rather than across each single hour of 24 hours. By applying three model variants on Nord Pool data, we achieve a weekly mean absolute percentage error (WMAE) of around 6–7% and an hourly mean absolute percentage error (MAPE) ranging from 8% to 11%. Out of sample results yields a WMAE and an hourly MAPE of around 5%. The models enable analysts and traders to forecast hourly day-ahead prices accurately. Moreover, the models are relatively straightforward and user-friendly to implement. They can be set up in any trading organization. - Highlights: ► Forecasting Nord Pool day-ahead prices with an autoregressive model. ► The model is based on but with the set of parameters reduced from 24 to 1. ► The model includes Nordic demand and Danish wind power as exogenous variables. ► Hourly mean absolute percentage error ranges from 8% to 11%. ► Out of sample results yields a WMAE and an hourly MAPE of around 5%.

  9. Coordination of bidding strategies in day-ahead energy and spinning reserve markets

    International Nuclear Information System (INIS)

    In this paper, the problem of building optimally coordinated bidding strategies for competitive suppliers in day-ahead energy and spinning reserve markets is addressed. It is assumed that each supplier bids 24 linear energy supply functions and 24 linear spinning reserve supply functions, one for each hour, into the energy and spinning reserve markets, respectively, and each market is cleared separately and simultaneously for all the 24 delivery hours. Each supplier makes decisions on unit commitment and chooses the coefficients in the linear energy and spinning reserve supply functions to maximise total benefits, subject to expectations about how rival suppliers will bid in both markets. Two different bidding schemes have been suggested for each hour, and based on them an overall coordinated bidding strategy in the day-ahead energy and spinning reserve market is then developed. Stochastic optimisation models are first developed to describe these two different bidding schemes and a genetic algorithm (GA) is then used to build the optimally coordinated bidding strategies for each scheme and to develop an overall bidding strategy for the day-ahead energy and spinning reserve markets. A numerical example is utilised to illustrate the essential features of the method. (Author)

  10. Self-scheduling for energy and spinning reserve of wind/CSP plants by a MILP approach

    International Nuclear Information System (INIS)

    This paper is on the self-scheduling for a power producer taking part in day-ahead joint energy and spinning reserve markets and aiming at a short-term coordination of wind power plants with concentrated solar power plants having thermal energy storage. The short-term coordination is formulated as a mixed-integer linear programming problem given as the maximization of profit subjected to technical operation constraints, including the ones related to a transmission line. Probability density functions are used to model the variability of the hourly wind speed and the solar irradiation in regard to a negative correlation. Case studies based on an Iberian Peninsula wind and concentrated solar power plants are presented, providing the optimal energy and spinning reserve for the short-term self-scheduling in order to unveil the coordination benefits and synergies between wind and solar resources. Results and sensitivity analysis are in favour of the coordination, showing an increase on profit, allowing for spinning reserve, reducing the need for curtailment, increasing the transmission line capacity factor. - Highlights: • Optimal self-scheduling of wind power with CSP plants having TES. • Joint model for trading energy and SR. • Evaluation of the benefit of wind power with CSP plants having TES. • Identification of synergies due to the negative correlation between wind and solar power

  11. Risk-constrained self-scheduling of a fuel and emission constrained power producer using rolling window procedure

    International Nuclear Information System (INIS)

    This work addresses a relevant methodology for self-scheduling of a price-taker fuel and emission constrained power producer in day-ahead correlated energy, spinning reserve and fuel markets to achieve a trade-off between the expected profit and the risk versus different risk levels based on Markowitz's seminal work in the area of portfolio selection. Here, a set of uncertainties including price forecasting errors and available fuel uncertainty are considered. The latter uncertainty arises because of uncertainties in being called for reserve deployment in the spinning reserve market and availability of power plant. To tackle the price forecasting errors, variances of energy, spinning reserve and fuel prices along with their covariances which are due to markets correlation are taken into account using relevant historical data. In order to tackle available fuel uncertainty, a framework for self-scheduling referred to as rolling window is proposed. This risk-constrained self-scheduling framework is therefore formulated and solved as a mixed-integer non-linear programming problem. Furthermore, numerical results for a case study are discussed. (author)

  12. Stochastic multiobjective self-scheduling of a power producer in joint energy and reserves markets

    International Nuclear Information System (INIS)

    This paper presents a stochastic multiobjective model for self-scheduling of a power producer which participates in the day-ahead joint energy and reserves markets. The objective of a power producer is to compromise the conflicting objectives of payoff maximization and gaseous emissions minimization when committing its generation of thermal units. The proposed schedule will be used by the power producers to decide on emission quota arbitrage opportunities and for strategic bidding to the energy and reserves market. The paper analyzes a scenario-based multiobjective model in which random distributions, such as price forecasting inaccuracies as well as forced outage of generating units are modeled as scenarios tree using a combined fuzzy c-mean/Monte-Carlo simulation (FCM/MCS) method. With the above procedure the stochastic multiobjective self-scheduling problem is converted into corresponding deterministic problems. Then a multiobjective mathematical programming (MMP) approach based on ε-constraint method is implemented for each deterministic scenario. Piecewise linearized fuel and emission cost functions are applied for computational efficiency and the model is formulated as a mixed-integer programming (MIP) problem. Numerical simulations for a power producer with 21 thermal units are discussed to demonstrate the performance of the proposed approach in increasing expected payoffs by adjusting the emission quota arbitrage opportunities. (author)

  13. Economic Benefit of Combining Wave and Wind Power Productions in Day-Ahead Electricity Markets

    DEFF Research Database (Denmark)

    Chozas, Julia Fernandez; Sørensen, H.C.; Helstrup Jensen, N.E.

    2012-01-01

    There is usually a cost associated to the integration of non-fully predictable renewables in electricity markets. This cost, named balancing cost, covers the difference between the bid to the day-ahead electricity market and the actual power produced. The objective of the paper is comparing...... the balancing costs of a diversified system including wind and wave power productions with a system based only on wind power. As a result, the paper estimates the balancing costs of wave converters, which are compared with the current balancing costs of wind turbines. The opportunities of a combined wave...

  14. Gain self-scheduled H∞ control for morphing aircraft in the wing transition process based on an LPV model

    Institute of Scientific and Technical Information of China (English)

    Yue Ting; Wang Lixin; Ai Junqiang

    2013-01-01

    This article investigates gain self-scheduled H∞ robust control system design for a tailless folding-wing morphing aircraft in the wing shape varying process.During the wing morphing phase,the aircraft's dynamic response will be governed by time-varying aerodynamic forces and moments.Nonlinear dynamic equations of the morphing aircraft are linearized by using Jacobian linearization approach,and a linear parameter varying (LPV) model of the morphing aircraft in wing folding is obtained.A multi-loop controller for the morphing aircraft is formulated to guarantee stability for the wing shape transition process.The proposed controller uses a set of inner-loop gains to provide stability using classical techniques,whereas a gain self-scheduled H∞ outer-loop controller is devised to guarantee a specific level of robust stability and performance for the time-varying dynamics.The closed-loop simulations show that speed and altitude vary slightly during the whole wing folding process,and they converge rapidly after the process ends.This proves that the gain self-scheduled H∞ robust controller can guarantee a satisfactory dynamic performance for the morphing aircraft during the whole wing shape transition process.Finally,the flight control system's robustness for the wing folding process is verified according to uncertainties of the aerodynamic parameters in the nonlinear model.

  15. Day-Ahead Energy Planning with 100% Electric Vehicle Penetration in the Nordic Region by 2050

    Directory of Open Access Journals (Sweden)

    Zhaoxi Liu

    2014-03-01

    Full Text Available This paper presents the day-ahead energy planning of passenger cars with 100% electric vehicle (EV penetration in the Nordic region by 2050. EVs will play an important role in the future energy systems which can both reduce the greenhouse gas (GHG emissions from the transport sector and provide the demand side flexibility required by smart grids. On the other hand, the EVs will increase the electricity consumption. In order to quantify the electricity consumption increase due to the 100% EV penetration in the Nordic region to facilitate the power system planning studies, the day-ahead energy planning of EVs has been investigated with different EV charging scenarios. Five EV charging scenarios have been considered in the energy planning analysis which are: uncontrolled charging all day, uncontrolled charging at home, timed charging, spot price based charging all day and spot price based charging at home. The demand profiles of the five charging analysis show that timed charging is the least favorable charging option and the spot priced based EV charging might induce high peak demands. The EV charging demand will have a considerable share of the energy consumption in the future Nordic power system.

  16. A two-stage model for a day-ahead paratransit planning problem

    NARCIS (Netherlands)

    Cremers, Maria L. A. G.; Klein Haneveld, Willem K.; van der Vlerk, Maarten H.

    2009-01-01

    We consider a dynamic planning problem for paratransit transportation. The focus is on a decision to take one day ahead: which requests to serve with own vehicles, and which requests to subcontract to taxis? We call this problem the day-ahead paratransit planning problem. The developed model is a no

  17. The Influence of Temperature on Spike Probability in Day-Ahead Power Prices

    NARCIS (Netherlands)

    R. Huisman (Ronald)

    2007-01-01

    textabstractIt is well known that day-ahead prices in power markets exhibit spikes. These spikes are sudden increases in the day-ahead price that occur because power production is not flexible enough to respond to demand and/or supply shocks in the short term. This paper focuses on how temperature i

  18. Customer reponse to day-ahead wholesale market electricity prices: Case study of RTP program experience in New York

    OpenAIRE

    Goldman, C; Hopper, N; Sezgen, O.; Moezzi, M.; Bharvirkar, R.; Neenan, B.; Boisvert, R; Cappers, P.; D. Pratt

    2004-01-01

    There is growing interest in policies, programs and tariffs that encourage customer loads to provide demand response (DR) to help discipline wholesale electricity markets. Proposals at the retail level range from eliminating fixed rate tariffs as the default service for some or all customer groups to reinstituting utility-sponsored load management programs with market-based inducements to curtail. Alternative rate designs include time-of-use (TOU), day-ahead real-time pricing (RTP), cri...

  19. Predictive densities for day-ahead electricity prices using time-adaptive quantile regression

    DEFF Research Database (Denmark)

    Jónsson, Tryggvi; Pinson, Pierre; Madsen, Henrik;

    2014-01-01

    is compared to that of four benchmark approaches and the well-known the generalist autoregressive conditional heteroskedasticity (GARCH) model over a three-year evaluation period. While all benchmarks are outperformed in terms of forecasting skill overall, the superiority of the semi-parametric model over......A large part of the decision-making problems actors of the power system are facing on a daily basis requires scenarios for day-ahead electricity market prices. These scenarios are most likely to be generated based on marginal predictive densities for such prices, then enhanced with a temporal...... dependence structure. A semi-parametric methodology for generating such densities is presented: it includes: (i) a time-adaptive quantile regression model for the 5%–95% quantiles; and (ii) a description of the distribution tails with exponential distributions. The forecasting skill of the proposed model...

  20. A new self-scheduling strategy for integrated operation of wind and pumped-storage power plants in power markets

    International Nuclear Information System (INIS)

    Highlights: → A strategy for integrated operation of wind and pumped-storage plants is proposed. → Participation of both plants in energy and ancillary service markets is modeled. → The uncertainty of wind production is modeled by a novel probabilistic function. → The proposed strategy is tested on a real case in the Spanish electricity market. -- Abstract: Competitive structure of power markets causes various challenges for wind resources to participate in these markets. Indeed, production uncertainty is the main cause of their low income. Thus, they are usually supported by system operators, which is in contrast with the competitive paradigm of power markets. In this paper, a new strategy for increasing the profits of wind resources is proposed. In the suggested strategy, a Generation Company (GenCo), who owns both wind and pumped-storage plants, self-schedules the integrated operation of them regarding the uncertainty of wind power generation. For presenting an integrated self-schedule and obtaining a real added value of the strategy, participation of the GenCo in energy and ancillary service markets is modeled. The self-scheduling strategy is based on stochastic programming techniques. Outputs of the problem include generation offers in day-ahead energy market and ancillary service markets, including spinning and regulation reserve markets. A Neural Network (NN) based technique is used for modeling the uncertainty of wind power production. The proposed strategy is tested on a real wind farm in mainland, Spain. Moreover, added value of the strategy is presented in different conditions of the market.

  1. Price forecasting of day-ahead electricity markets using a hybrid forecast method

    International Nuclear Information System (INIS)

    Research highlights: → A hybrid method is proposed to forecast the day-ahead prices in electricity market. → The method combines Wavelet-ARIMA and RBFN network models. → PSO method is applied to obtain optimum RBFN structure for avoiding over fitting. → One of the merits of the proposed method is lower need to the input data. → The proposed method has more accurate behavior in compare with previous methods. -- Abstract: Energy price forecasting in a competitive electricity market is crucial for the market participants in planning their operations and managing their risk, and it is also the key information in the economic optimization of the electric power industry. However, price series usually have a complex behavior due to their nonlinearity, nonstationarity, and time variancy. In this paper, a novel hybrid method to forecast day-ahead electricity price is proposed. This hybrid method is based on wavelet transform, Auto-Regressive Integrated Moving Average (ARIMA) models and Radial Basis Function Neural Networks (RBFN). The wavelet transform provides a set of better-behaved constitutive series than price series for prediction. ARIMA model is used to generate a linear forecast, and then RBFN is developed as a tool for nonlinear pattern recognition to correct the estimation error in wavelet-ARIMA forecast. Particle Swarm Optimization (PSO) is used to optimize the network structure which makes the RBFN be adapted to the specified training set, reducing computation complexity and avoiding overfitting. The proposed method is examined on the electricity market of mainland Spain and the results are compared with some of the most recent price forecast methods. The results show that the proposed hybrid method could provide a considerable improvement for the forecasting accuracy.

  2. Forecasting day ahead electricity spot prices: The impact of the EXAA to other European electricity markets

    OpenAIRE

    Florian Ziel; Rick Steinert; Sven Husmann

    2015-01-01

    In our paper we analyze the relationship between the day-ahead electricity price of the Energy Exchange Austria (EXAA) and other day-ahead electricity prices in Europe. We focus on markets, which settle their prices after the EXAA, which enables traders to include the EXAA price into their calculations. For each market we employ econometric models to incorporate the EXAA price and compare them with their counterparts without the price of the Austrian exchange. By employing a forecasting study...

  3. Everything you need to know to operate on Day-Ahead{sup TM}; Tout ce que vous devez savoir pour intervenir sur Powernext Day-Ahead{sup TM}

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-05-15

    The introduction of a power exchange in France is a direct response to the opening up of the European electricity markets. Powernext SA is a Multilateral Trading Facility in charge of managing the French power exchange through an optional and anonymous organised exchange offering: - Day-ahead contracts for the management of volume risk on Powernext Day-Ahead{sup TM} since 21 November 2001, - Medium term contracts for the management of price risk on Powernext Futures{sup TM} since 18 June 2004. This document is the user's guide of Powernext Day-Ahead{sup TM}. It presents: 1 - the power exchange in France (market model, Powernext's regulatory environment, general market operations, 2 - Powernext Day-Ahead{sup TM} members (membership, agreement, start-up notification, tariffs, standing obligations, membership termination), 3 - Powernext Day-Ahead{sup TM} products (specifications, management), 4 - trading (connections, system flow chart, ElWeb client installation and daily connections, portfolio-management, single bidding, type of order, submitting, importing, saving, sending, modifying or canceling an order form, transmission problems, block bidding block bid characteristics, sending, saving, transmitting, modifying and canceling a block bid, price calculations, blind auction procedure, example, taking into account block bids, rounding off rules, consulting and saving the results, sample documents, auction validation), 5 - clearing (LCH.Clearnet SA, legal framework, clearing agreement, PP-DPES agreement, market security, initial margin, daily adjustments, additional margin calls, trade-related financial flows, net financial position, value-added tax, settlement statements, general idea, characteristics and transmission method of settlement statements sample Documents, cash calls, settlement, default, sample cash call documents, financial Reports), 6 - delivery (balance responsible entity, file characteristics and transmission, imbalance settlement

  4. Application of a Gradient Descent Continuous Actor-Critic Algorithm for Double-Side Day-Ahead Electricity Market Modeling

    Directory of Open Access Journals (Sweden)

    Huiru Zhao

    2016-09-01

    Full Text Available An important goal of China’s electric power system reform is to create a double-side day-ahead wholesale electricity market in the future, where the suppliers (represented by GenCOs and demanders (represented by DisCOs compete simultaneously with each other in one market. Therefore, modeling and simulating the dynamic bidding process and the equilibrium in the double-side day-ahead electricity market scientifically is not only important to some developed countries, but also to China to provide a bidding decision-making tool to help GenCOs and DisCOs obtain more profits in market competition. Meanwhile, it can also provide an economic analysis tool to help government officials design the proper market mechanisms and policies. The traditional dynamic game model and table-based reinforcement learning algorithm have already been employed in the day-ahead electricity market modeling. However, those models are based on some assumptions, such as taking the probability distribution function of market clearing price (MCP and each rival’s bidding strategy as common knowledge (in dynamic game market models, and assuming the discrete state and action sets of every agent (in table-based reinforcement learning market models, which are no longer applicable in a realistic situation. In this paper, a modified reinforcement learning method, called gradient descent continuous Actor-Critic (GDCAC algorithm was employed in the double-side day-ahead electricity market modeling and simulation. This algorithm can not only get rid of the abovementioned unrealistic assumptions, but also cope with the Markov decision-making process with continuous state and action sets just like the real electricity market. Meanwhile, the time complexity of our proposed model is only O(n. The simulation result of employing the proposed model in the double-side day-ahead electricity market shows the superiority of our approach in terms of participant’s profit or social welfare

  5. A Day-Ahead Dispatching Strategy for Power Pool Composed of Wind Farms, Photovoltaic Generations, Pumped-Storage Power Stations, Gas Turbine Power Plants and Energy Storage Systems Based on Multi Frequency Scale Analysis%基于功率多频率尺度分析的风光水气储联合系统日前调度策略

    Institute of Scientific and Technical Information of China (English)

    马静; 石建磊; 李文泉; 王增平

    2013-01-01

    Based on multi frequency scale analysis on power output of wind farms and photovoltaic (PV) generation (PWP), a day-ahead dispatching strategy for power pool composed of wind farms, photovoltaic generations, pumped-storage power stations, gas turbine power plants and energy storage systems is proposed. Firstly, according to the control objectives the filter analysis on PWP is performed to extract PWP components corresponding to different frequency scales to draft output schedulings for of all kinds of complementary power generations in the power pool; then using improved particle swamp optimization (PSO) the total power output of the power pool is computed;finally, based on different day-ahead dispatching modes and considering stability and wind power accommodation capability of the power pool, the per-unit generation costs of wind farms, photovoltaic generations, pumped-storage power stations, gas turbine power plants and energy storage systems are optimized to draft final output schedulings. Results of calculation example show that comparing with traditional optimization models and optimization algorithms, the proposed method can cope with the power fluctuation due to grid-connection of large-scale wind farms and PV generations to implement stationary power output of the power pool, meanwhile the economy, efficiency, low-carbon operation and environmental protection of the power pool can be ensured.%  提出一种基于功率多频率尺度分析的风光水气储联合系统日前调度策略。该策略首先根据控制目标对风光出力(power of wind photovoltaic,PWP)进行滤波分析,提取不同频率尺度下的PWP分量,制定各类补偿电站出力计划;然后利用改进粒子群优化算法并行优化各电站内部综合成本,计算联合系统总体输出功率;最后依据不同日前调度模式,考虑稳定性和风光消纳能力,优化风光水气储系统单位发电成本,制定出力计划。算例分析结果

  6. Day-ahead tariffs for the alleviation of distribution grid congestion from electric vehicles

    DEFF Research Database (Denmark)

    O'Connell, Niamh; Wu, Qiuwei; Østergaard, Jacob;

    2012-01-01

    An economically efficient day-ahead tariff (DT) is proposed with the purpose of preventing the distribution grid congestion resulting from electric vehicle (EV) charging scheduled on a dayahead basis. The DT concept developed herein is derived from the locational marginal price (LMP), in particular...... the congestion cost component of the LMP. A step-wise congestion management structure has been developed whereby the distribution system operator (DSO) predicts congestion for the coming day and publishes DTs prior to the clearing of the day-ahead market. EV fleet operators (FOs) optimize their EV charging...... schedules with respect to the predicted day-ahead prices and the published DTs, thereby avoiding congestion while still minimizing the charging cost. A Danish 400V distribution network is used to carry out case studies to illustrate the effectiveness of the developed concept for the prevention...

  7. Day-Ahead Energy Planning with 100% Electric Vehicle Penetration in the Nordic Region by 2050

    DEFF Research Database (Denmark)

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

    2014-01-01

    This paper presents the day-ahead energy planning of passenger cars with 100% electric vehicle (EV) penetration in the Nordic region by 2050. EVs will play an important role in the future energy systems which can both reduce the greenhouse gas (GHG) emission from the transport sector and provide...... demand side flexibility required by the smart grids. On the other hand, the EVs will increase the electricity consumption. In order to quantify the electricity consumption increase due to the 100% EV penetration in the Nordic region to facilitate the power system planning studies, the day-ahead energy...

  8. Application of Analytics using R Programming for Forecasting Day-ahead Electricity Demand

    Directory of Open Access Journals (Sweden)

    Chandrabhushan Kesavabhotla

    2012-11-01

    Full Text Available Analytics technologies are becoming increasingly important for the organizations to mine and get insights into large amount of structured and unstructured data, and also to enable effective decision making for the management. One of the challenges for power industry is to estimate the Day-ahead power demand specifically to predict the peak and low demand periods. In this paper, the modeling techniques of analytics for forecasting are discussed. This paper investigates application of ARMA and GARCH modeling techniques to fit the historical data and estimate the coefficients to predict the Day-ahead electricity demand. R-Programming is used to fit the models.

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

    DEFF Research Database (Denmark)

    Soares, João; Valle, Zita; Morais, Hugo

    2013-01-01

    of a new hybrid method combing a particle swarm approach and a deterministic technique based on mixedinteger linear programming (MILP) to solve the day-ahead scheduling minimizing total operation costs from the aggregator point of view. A realistic mathematical formulation, considering the electric network...

  10. Optimal Bidding Strategies for Wind Power Producers in the Day-ahead Electricity Market

    Directory of Open Access Journals (Sweden)

    Xiaolin Liu

    2012-11-01

    Full Text Available Wind Power Producers (WPPs seek to maximize profit and minimize the imbalance costs when bidding into the day-ahead market, but uncertainties in the hourly available wind and forecasting errors make the bidding risky. This paper assumes that hourly wind power output given by the forecast follows a normal distribution, and proposes three different bidding strategies, i.e., the expected profit-maximization strategy (EPS, the chance-constrained programming-based strategy (CPS and the multi-objective bidding strategy (ECPS. Analytical solutions under the three strategies are obtained. Comparisons among the three strategies are conducted on a hypothetical wind farm which follows the Spanish market rules. Results show that bid under the EPS is highly dependent on market clearing price, imbalance prices, and also the mean value and standard deviation of wind forecast, and that bid under the CPS is largely driven by risk parameters and the mean value and standard deviation of the wind forecast. The ECPS combining both EPS and CPS tends to choose a compromise bid. Furthermore, the ECPS can effectively control the tradeoff between expected profit and target profit for WPPs operating in volatile electricity markets.

  11. Generators' bidding behavior in the NYISO day-ahead wholesale electricity market

    International Nuclear Information System (INIS)

    This paper proposes a statistical and econometric model to analyze the generators' bidding behavior in the NYISO day-ahead wholesale electricity market. The generator level bidding data show very strong persistence in generators' grouping choices over time. Using dynamic random effect ordered probit model, we find that persistence is characterized by positive state dependence and unobserved heterogeneity and state dependence is more important than unobserved heterogeneity. The finding of true state dependence suggests a scope for economic policy intervention. If NYISO can implement an effective policy to switch generators from higher price groups to lower price groups, the effect is likely to be lasting. As a result, the market price can be lowered in the long-run. Generators' offered capacity is estimated by a two-stage sample selection model. The estimated results show that generators in higher-priced groups tend to withhold their capacity strategically to push up market prices. It further confirms the importance of an effective policy to turn generators into lower price groups in order to mitigate unexpected price spikes. The simulated market prices based on our estimated aggregate supply curve can replicate most volatility of actual DA market prices. Applying our models to different demand assumptions, we find that demand conditions can affect market prices significantly. It validates the importance of introducing demand side management during the restructure of electricity industry. (author)

  12. Risk-constrained dynamic self-scheduling of a pumped-storage plant in the energy and ancillary service markets

    Energy Technology Data Exchange (ETDEWEB)

    Kazempour, S. Jalal; Moghaddam, M. Parsa; Haghifam, M.R.; Yousefi, G.R. [Department of Electrical Engineering, Tarbiat Modares University (TMU), Tehran (Iran)

    2009-05-15

    This work addresses a new framework for self-scheduling of an individual price-taker pumped-storage plant in a day-ahead (DA) market. The goal is achieving the best trade-off between the expected profit and the risks when the plant participates in DA energy, spinning reserve and regulation markets. In this paper, a set of uncertainties including price forecasting errors and also the uncertainty of power delivery requests in the ancillary service markets are contemplated. Considering these uncertainties, a new approach is proposed which is called dynamic self-scheduling (DSS). This risk-constrained dynamic self-scheduling problem is therefore formulated and solved as a mixed integer programming (MIP) problem. Numerical results for a case study are discussed. (author)

  13. Demand Response from Day-Ahead Hourly Pricing for Large Customers

    International Nuclear Information System (INIS)

    Day-ahead default-service RTP for large customers not only improves the linkage between wholesale and retail markets, but also promotes the development of retail competition. The default service sets a standard for competitive alternatives and its structure shapes the types of retail market products that develop. (author)

  14. Multi-objective parallel particle swarm optimization for day-ahead Vehicle-to-Grid scheduling

    DEFF Research Database (Denmark)

    Soares, Joao; Vale, Zita; Canizes, Bruno;

    2013-01-01

    This paper presents a methodology for multi-objective day-ahead energy resource scheduling for smart grids considering intensive use of distributed generation and Vehicle-To-Grid (V2G). The main focus is the application of weighted Pareto to a multi-objective parallel particle swarm approach aimi...

  15. Day-ahead distributed energy resource scheduling using differential search algorithm

    DEFF Research Database (Denmark)

    Soares, J.; Lobo, C.; Silva, M.;

    2015-01-01

    The number of dispersed energy resources is growing every day, such as the use of more distributed generators. This paper deals with energy resource scheduling model in future smart grids. The methodology can be used by virtual power players (VPPs) considering day-ahead time horizon. This method ...

  16. The impact of renewable energies on EEX day-ahead electricity prices

    International Nuclear Information System (INIS)

    In this paper, we analyze the impact of renewable energies, wind and photovoltaic, on the formation of day-ahead electricity prices at EEX. We give an overview of the policy decisions concerning the promotion of renewable energy sources in Germany and discuss their consequences on day-ahead prices. An analysis of electricity spot prices reveals that the introduction of renewable energies enhances extreme price changes. In the frame of a dynamic fundamental model, we show that there has been a continuous electricity price adaption process to market fundamentals. Furthermore, the fundamental drivers of prices differ among hours with different load profiles. Our results imply that renewable energies decrease market spot prices and have implications on the traditional fuel mix for electricity production. However, the prices for the final consumers increased overall because they must pay in addition the feed-in tariffs for the promotion of renewable energy. - Highlights: • We analyze the impact of renewable energies on the day-ahead electricity prices at EEX. • We discuss the impact of renewables on day-ahead prices. • We show a continuous electricity price adaption process to market fundamentals. • Renewable energies decrease market spot prices and shift the merit order curve. • The prices for the final consumers however increased because of feed-in tariffs

  17. The effect of contingency analysis on the nodal prices in the day-ahead market

    International Nuclear Information System (INIS)

    We look at the effect of modeling branch-outage contingencies on locational marginal prices. To model contingencies in the day-ahead auction, we formulate a two-stage stochastic program. Rather than follow the current practice of including a list of possible contingencies that must be satisfied, we incorporate a larger set of contingencies in the model and allow contingencies to result in load reductions/outages at a cost. The model can be used and interpreted in two ways. One is to look at the tradeoff between reliability and outage costs. Another is to consider the load losses resulting from a contingency to be consumer offers of load reductions in response to line outages as part of the day-ahead auction. In analyzing the model structure, we find that the prices in the model closer in definition to those currently used in the day-ahead auction do not maximize expected surplus because the day-ahead auction produces prices that assume shortages will never occur. This raises issues with the design of auctions with important stochastic elements in the market. We present results for a 68-node grid with 86 branches (lines and transformers) to illustrate how prices and expected values change as the costs of outages are varied. (author)

  18. Everything you need to know to operate on Day-AheadTM

    International Nuclear Information System (INIS)

    The introduction of a power exchange in France is a direct response to the opening up of the European electricity markets. Powernext SA is a Multilateral Trading Facility in charge of managing the French power exchange through an optional and anonymous organised exchange offering: - Day-ahead contracts for the management of volume risk on Powernext Day-AheadTM since 21 November 2001, - Medium term contracts for the management of price risk on Powernext FuturesTM since 18 June 2004. This document is the user's guide of Powernext Day-AheadTM. It presents: 1 - the power exchange in France (market model, Powernext's regulatory environment, general market operations, 2 - Powernext Day-AheadTM members (membership, agreement, start-up notification, tariffs, standing obligations, membership termination), 3 - Powernext Day-AheadTM products (specifications, management), 4 - trading (connections, system flow chart, ElWeb client installation and daily connections, portfolio-management, single bidding, type of order, submitting, importing, saving, sending, modifying or canceling an order form, transmission problems, block bidding block bid characteristics, sending, saving, transmitting, modifying and canceling a block bid, price calculations, blind auction procedure, example, taking into account block bids, rounding off rules, consulting and saving the results, sample documents, auction validation), 5 - clearing (LCH.Clearnet SA, legal framework, clearing agreement, PP-DPES agreement, market security, initial margin, daily adjustments, additional margin calls, trade-related financial flows, net financial position, value-added tax, settlement statements, general idea, characteristics and transmission method of settlement statements sample Documents, cash calls, settlement, default, sample cash call documents, financial Reports), 6 - delivery (balance responsible entity, file characteristics and transmission, imbalance settlement, interconnection access), contacts and glossary

  19. Morphological impact of a storm can be predicted three days ahead

    Science.gov (United States)

    Baart, F.; van Ormondt, M.; van Thiel de Vries, J. S. M.; van Koningsveld, M.

    2016-05-01

    People living behind coastal dunes depend on the strength and resilience of dunes for their safety. Forecasts of hydrodynamic conditions and morphological change on a timescale of several days can provide essential information to protect lives and property. In order for forecasts to protect they need be relevant, accurate, provide lead time, and information on confidence. Here we show how confident one can be in morphological predictions of several days ahead. The question is answered by assessing the forecast skill as a function of lead time. The study site in the town of Egmond, the Netherlands, where people depend on the dunes for their safety, is used because it is such a rich data source, with a history of forecasts, tide gauges and bathymetry measurements collected by video cameras. Even though the forecasts are on a local scale, the methods are generally applicable. It is shown that the intertidal beach volume change can be predicted up to three days ahead.

  20. Empirical Analysis of Developments in the Day Ahead Electricity Markets in India

    OpenAIRE

    Sinha, Pankaj; Mathur, Kritika

    2016-01-01

    Given the thrust on the deregulation of electricity markets in India since 2003, the short term electricity market with power exchanges in particular have evolved rapidly to support the growth of the power markets in an efficient manner. Since their year of inception 2008, power exchanges are now more efficient and are able to mitigate risks arising from price volatility for the participants to a large extent. This paper throws light on the trading of day ahead electricity contracts in India....

  1. Customer Strategies for Responding to Day-Ahead Market HourlyElectricity Pricing

    Energy Technology Data Exchange (ETDEWEB)

    Goldman, Chuck; Hopper, Nicole; Bharvirkar, Ranjit; Neenan,Bernie; Boisvert, Dick; Cappers, Peter; Pratt, Donna; Butkins, Kim

    2005-08-25

    Real-time pricing (RTP) has been advocated as an economically efficient means to send price signals to customers to promote demand response (DR) (Borenstein 2002, Borenstein 2005, Ruff 2002). However, limited information exists that can be used to judge how effectively RTP actually induces DR, particularly in the context of restructured electricity markets. This report describes the second phase of a study of how large, non-residential customers' adapted to default-service day-ahead hourly pricing. The customers are located in upstate New York and served under Niagara Mohawk, A National Grid Company (NMPC)'s SC-3A rate class. The SC-3A tariff is a type of RTP that provides firm, day-ahead notice of hourly varying prices indexed to New York Independent System Operator (NYISO) day-ahead market prices. The study was funded by the California Energy Commission (CEC)'s PIER program through the Demand Response Research Center (DRRC). NMPC's is the first and longest-running default-service RTP tariff implemented in the context of retail competition. The mix of NMPC's large customers exposed to day-ahead hourly prices is roughly 30% industrial, 25% commercial and 45% institutional. They have faced periods of high prices during the study period (2000-2004), thereby providing an opportunity to assess their response to volatile hourly prices. The nature of the SC-3A default service attracted competitive retailers offering a wide array of pricing and hedging options, and customers could also participate in demand response programs implemented by NYISO. The first phase of this study examined SC-3A customers' satisfaction, hedging choices and price response through in-depth customer market research and a Constant Elasticity of Substitution (CES) demand model (Goldman et al. 2004). This second phase was undertaken to answer questions that remained unresolved and to quantify price response to a higher level of granularity. We accomplished these

  2. Thermal energy storage for electricity-driven space heating in a day-ahead electricity market

    DEFF Research Database (Denmark)

    Pensini, Alessandro

    2012-01-01

    Thermal Energy Storage (TES) in a space heating (SH) application was investigated. The study aimed to determine the economic benefits of introducing TES into an electricity-driven SH system under a day-ahead electricity market. The performance of the TES was assessed by comparing the cost...... of electricity in a system with a TES unit to the case where no storage is in use and the entire heat requirement is fulfilled by purchasing electricity according to the actual load. The study had two goals: 1. Determining how the size – in terms of electricity input (Pmax) and energy capacity (Emax...

  3. The impact of wind power on APX day-ahead electricity prices in the Netherlands VVM-Intermittency project

    Energy Technology Data Exchange (ETDEWEB)

    Nieuwenhout, F.D.J. [ECN Policy Studies, Amsterdam (Netherlands); Brand, A.J. [ECN Wind Energy, Petten (Netherlands)

    2013-02-15

    A detailed analysis was conducted to assess to what extent availability of wind energy has influenced day-ahead electricity prices in the Netherlands over the period 2006-2009. With a meteorological model, time series of day-ahead wind forecasts were generated, and these were compared with APX-ENDEX day-ahead market prices. Wind energy contributes to only 4% of electricity generation in the Netherlands, but was found to depress average day-ahead market prices by about 5%. With the help of the bid curves on the APX-ENDEX day-ahead market for 2009, a model was developed to assess the impact of increasing levels of wind generation on power prices in the Netherlands. One of the main findings is that the future impact on prices will be less than in the past. With an increase of installed wind capacity from 2200 MW to 6000 MW, average day-ahead prices are expected to be depressed by an additional 6% in case no additional conventional generation is assumed. Taking into account existing government policy on wind and ongoing investments in new conventional power plants, prices in 2016 will be only 3% lower.

  4. Co-optimization of Energy and Demand-Side Reserves in Day-Ahead Electricity Markets

    Science.gov (United States)

    Surender Reddy, S.; Abhyankar, A. R.; Bijwe, P. R.

    2015-04-01

    This paper presents a new multi-objective day-ahead market clearing (DAMC) mechanism with demand-side reserves/demand response (DR) offers, considering realistic voltage-dependent load modeling. The paper proposes objectives such as social welfare maximization (SWM) including demand-side reserves, and load served error (LSE) minimization. In this paper, energy and demand-side reserves are cleared simultaneously through co-optimization process. The paper clearly brings out the unsuitability of conventional SWM for DAMC in the presence of voltage-dependent loads, due to reduction of load served (LS). Under such circumstances multi-objective DAMC with DR offers is essential. Multi-objective Strength Pareto Evolutionary Algorithm 2+ (SPEA 2+) has been used to solve the optimization problem. The effectiveness of the proposed scheme is confirmed with results obtained from IEEE 30 bus system.

  5. Powernext Day-Ahead. Powernext Futures. Powernext Carbon. Powernext Weather. Activity assessment first-half 2006; Powernext Day-Ahead. Powernext Futures. Powernext Carbon. Powernext Weather. Bilan d'activite premier semestre 2006

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    Powernext SA is a Multilateral Trading Facility which organizes and warrants the transactions on the European power exchange and CO{sub 2} exchange markets. This activity report presents the highlights of the market and of Powernext in the first half of 2006: market conditions, prices and traded volumes on Powernext (Powernext Day-Ahead{sup TM} in the case of day-ahead contracts, Powernext Futures{sup TM} in the case of medium-term contracts, and Powernext Carbon in the case of CO{sub 2}), new active members, and liquidity on the power market. (J.S.)

  6. Robust optimisation for self-scheduling and bidding strategies of hybrid CSP-fossil power plants

    DEFF Research Database (Denmark)

    Pousinho, H.M.I.; Contreras, J.; Pinson, P.;

    2015-01-01

    between the molten-salt thermal energy storage (TES) and a fossil-fuel backup to overcome solar irradiation insufficiency, but with emission allowances constrained in the backup system to mitigate carbon footprint. A robust optimisation-based approach is proposed to provide the day-ahead self...

  7. Customer response to day-ahead wholesale market electricity prices: Case study of RTP program experience in New York

    Energy Technology Data Exchange (ETDEWEB)

    Goldman, C.; Hopper, N.; Sezgen, O.; Moezzi, M.; Bharvirkar, R.; Neenan, B.; Boisvert, R.; Cappers, P.; Pratt, D.

    2004-07-01

    There is growing interest in policies, programs and tariffs that encourage customer loads to provide demand response (DR) to help discipline wholesale electricity markets. Proposals at the retail level range from eliminating fixed rate tariffs as the default service for some or all customer groups to reinstituting utility-sponsored load management programs with market-based inducements to curtail. Alternative rate designs include time-of-use (TOU), day-ahead real-time pricing (RTP), critical peak pricing, and even pricing usage at real-time market balancing prices. Some Independent System Operators (ISOs) have implemented their own DR programs whereby load curtailment capabilities are treated as a system resource and are paid an equivalent value. The resulting load reductions from these tariffs and programs provide a variety of benefits, including limiting the ability of suppliers to increase spot and long-term market-clearing prices above competitive levels (Neenan et al., 2002; Boren stein, 2002; Ruff, 2002). Unfortunately, there is little information in the public domain to characterize and quantify how customers actually respond to these alternative dynamic pricing schemes. A few empirical studies of large customer RTP response have shown modest results for most customers, with a few very price-responsive customers providing most of the aggregate response (Herriges et al., 1993; Schwarz et al., 2002). However, these studies examined response to voluntary, two-part RTP programs implemented by utilities in states without retail competition.1 Furthermore, the researchers had limited information on customer characteristics so they were unable to identify the drivers to price response. In the absence of a compelling characterization of why customers join RTP programs and how they respond to prices, many initiatives to modernize retail electricity rates seem to be stymied.

  8. Not All Large Customers are Made Alike: Disaggregating Response to Default-Service Day-Ahead Market Pricing

    International Nuclear Information System (INIS)

    For decades, policymakers and program designers have gone on the assumption that large customers, particularly industrial facilities, are the best candidates for realtime pricing (RTP). This assumption is based partly on practical considerations (large customers can provide potentially large load reductions) but also on the premise that businesses focused on production cost minimization are most likely to participate and respond to opportunities for bill savings. Yet few studies have examined the actual price response of large industrial and commercial customers in a disaggregated fashion, nor have factors such as the impacts of demand response (DR) enabling technologies, simultaneous emergency DR program participation and price response barriers been fully elucidated. This second-phase case study of Niagara Mohawk Power Corporation (NMPC)'s large customer RTP tariff addresses these information needs. The results demonstrate the extreme diversity of large customers' response to hourly varying prices. While two-thirds exhibit some price response, about 20 percent of customers provide 75-80 percent of the aggregate load reductions. Manufacturing customers are most price-responsive as a group, followed by government/education customers, while other sectors are largely unresponsive. However, individual customer response varies widely. Currently, enabling technologies do not appear to enhance hourly price response; customers report using them for other purposes. The New York Independent System Operator (NYISO)'s emergency DR programs enhance price response, in part by signaling to customers that day-ahead prices are high. In sum, large customers do currently provide moderate price response, but there is significant room for improvement through targeted programs that help customers develop and implement automated load-response strategies

  9. Powernext Day-Ahead. Powernext Futures. Powernext Carbon. Powernext Weather. 2006 activity assessment; Powernext Day-Ahead. Powernext Futures. Powernext Carbon. Powernext Weather. Bilan d'activite 2006

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    Powernext SA is a Multilateral Trading Facility which organizes and warrants the transactions on the European power exchange and CO{sub 2} exchange markets. This activity report presents the highlights of the market and of Powernext in 2006: market conditions (prices on the electricity market, prices on the CO{sub 2} emission allowances market, weather conditions, institutional aspects of the CO{sub 2} market, power generation and consumption, situation at the borders, fuel prices), traded volumes on Powernext (Powernext Day-Ahead{sup TM} in the case of day-ahead contracts, Powernext Futures{sup TM} in the case of medium-term contracts, and Powernext Carbon in the case of CO{sub 2}), new active members, and Powernext liquidity on the power market. (J.S.)

  10. Optimal bidding of a profit-maximizing hydropowerproducer in day-ahead and real-time markets

    OpenAIRE

    Vardanyan, Yelena; Hesamzadeh, Mohammad

    2014-01-01

    This paper develops a price-driven optimal bidding strategy to day-ahead and real-time markets for a profit maximizer hydro power producer. The electricity prices in different market places are unknown when the bidding takes place. The optimal bidding problem is modeled as a multi-stage stochastic program considering the market prices continuously clearing nature. Specifically for that purpose rolling planning is applied, which allow re-forecasting and re-dispatching according to the arrival ...

  11. Day-Ahead Optimized Economic Dispatching for Combined Cooling, Heating and Power in Micro Energy-Grid Based on Hessian Interior Point Method%基于Hessian内点法的微型能源网日前冷热电联供经济优化调度

    Institute of Scientific and Technical Information of China (English)

    徐青山; 曾艾东; 王凯; 蒋菱

    2016-01-01

    微型能源网包含冷、热、电和气4种能源形式,具有负荷种类多样、供能设备丰富的特点。在对微型能源网内多种供能及蓄能设备进行建模的基础上,提出基于集中互连能源交换网络的冷热电联供微型能源网的供能架构,架构内冷热电负荷被细分为纯电负荷、热水负荷、空间热负荷、冷冻制冷负荷和空间冷负荷,围绕该架构建立冷热电联供微型能源网经济优化调度模型,采用基于Hessian矩阵迭代的内点法对模型进行了求解。算例表明,通过调度微型能源网内各供能设备的运行方式和出力,可以显著降低系统的日运行费用,实现冷热电联供微型能源网的经济优化运行,得出的合理调度方案证实了所提模型和求解方法的正确性及有效性。%Micro energy-grid contains four forms of energy: cold, heat,electricity and gas, possessing features of diversified load forms and energy supply devices. After modeling of a variety of energy supply and storage devices, this paper proposed an energy supply infrastructure for combined cooling heating and power (CCHP)-based micro energy-grid based on centralized and interconnected energy exchange network. Loads are subdivided into pure electricity, hot water, space heating, refrigeration and space cooling. Optimized economic dispatching model of CCHP-based micro energy-grid is established according to the infrastructure. The model is solved with interior point method with Hessian matrix iteration. Study case shows that the dispatching method can achieve optimized economic operation of micro energy-grid by reducing operation cost remarkably through controlling operation mode and output of energy supply and storage equipment. Rational dispatching method confirms correctness and validity of the proposed model and solving method.

  12. Pricing Energy and Ancillary Services in a Day-Ahead Market for a Price-Taker Hydro Generating Company Using a Risk-Constrained Approach

    Directory of Open Access Journals (Sweden)

    Perica Ilak

    2014-04-01

    Full Text Available This paper analyzes a price-taker hydro generating company which participates simultaneously in day-ahead energy and ancillary services markets. An approach for deriving marginal cost curves for energy and ancillary services is proposed, taking into consideration price uncertainty and opportunity cost of water, which can later be used to determine hourly bid curves. The proposed approach combines an hourly conditional value-at-risk, probability of occurrence of automatic generation control states and an opportunity cost of water to determine energy and ancillary services marginal cost curves. The proposed approach is in a linear constraint form and is easy to implement in optimization problems. A stochastic model of the hydro-economic river basin is presented, based on the actual Vinodol hydropower system in Croatia, with a complex three-dimensional relationship between the power produced, the discharged water, and the head of associated reservoir.

  13. Economic impact of price forecasting inaccuracies on self-scheduling of generation companies

    International Nuclear Information System (INIS)

    This paper studies the economic impact of using inaccurate price forecasts on self-scheduling of generation companies (GenCos) in a competitive electricity market. Four alternative sets of price forecasts are used in this study which have different levels of accuracy. The economic impact of price forecast inaccuracies is calculated by comparing the economic benefits of the GenCos in two self-scheduling scenarios. In the first scenario, electricity market price forecasts are used to optimally schedule the GenCos' next day operation. In the second scenario, perfect price forecasts, i.e., actual market prices, are used for self-scheduling of the GenCos. Two indices are utilized to quantify the differences in the economic benefits of the GenCos under the two scenarios. Simulation results are provided and discussed for two typical and inherently different GenCos, i.e., a hydro-based producer and a thermal-based producer. (author)

  14. Assessment of the Impact of Stochastic Day-Ahead SCUC on Economic and Reliability Metrics at Multiple Timescales: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Wu, H.; Ela, E.; Krad, I.; Florita, A.; Zhang, J.; Hodge, B. M.; Ibanez, E.; Gao, W.

    2015-03-01

    This paper incorporates the stochastic day-ahead security-constrained unit commitment (DASCUC) within a multi-timescale, multi-scheduling application with commitment, dispatch, and automatic generation control. The stochastic DASCUC is solved using a progressive hedging algorithm with constrained ordinal optimization to accelerate the individual scenario solution. Sensitivity studies are performed in the RTS-96 system, and the results show how this new scheduling application would impact costs and reliability with a closer representation of timescales of system operations in practice.

  15. An Assessment of the Impact of Stochastic Day-Ahead SCUC on Economic and Reliability Metrics at Multiple Timescales

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Hongyu; Ela, Erik; Krad, Ibrahim; Florita, Anthony; Zhang, Jie; Hodge, Bri-Mathias; Ibanez, Eduardo; Gao, Wenzhong

    2015-10-05

    This paper incorporates the stochastic day-ahead security-constrained unit commitment (DASCUC) within a multi-timescale, multi-scheduling application with commitment, dispatch, and automatic generation control. The stochastic DASCUC is solved using a progressive hedging algorithm with constrained ordinal optimization to accelerate the individual scenario solution. Sensitivity studies are performed in the RTS-96 system, and the results show how this new scheduling application would impact costs and reliability with a closer representation of timescales of system operations in practice.

  16. Optimal day-ahead network-constrained power system's market operations planning using an interior point method

    International Nuclear Information System (INIS)

    A model for Day-Ahead-Market (DAM) operations planning is proposed. The model considers offers and bids for power supply as well as for spinning reserve, and is able to consider network security through a DC power-flow model. DAM operations planning is the first task to be solved by deregulated environment system operators, such as the Independent System Operator (ISO), proposed in several jurisdictions planning deregulation of the electricity industry. This paper presents preliminary results of a study designed to solve a general DAM operations planning model that is able to accommodate most of the current and foreseeable deregulated operations policies. The large scale optimization problem is solved using the Primal-Dual Logarithmic Barrier Interior-Point method. Modelling results for a 14-node system are discussed. 11 refs., 2 figs

  17. Probability-Weighted LMP and RCP for Day-Ahead Energy Markets using Stochastic Security-Constrained Unit Commitment: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Ela, E.; O' Malley, M.

    2012-06-01

    Variable renewable generation resources are increasing their penetration on electric power grids. These resources have weather-driven fuel sources that vary on different time scales and are difficult to predict in advance. These characteristics create challenges for system operators managing the load balance on different timescales. Research is looking into new operational techniques and strategies that show great promise on facilitating greater integration of variable resources. Stochastic Security-Constrained Unit Commitment models are one strategy that has been discussed in literature and shows great benefit. However, it is rarely used outside the research community due to its computational limits and difficulties integrating with electricity markets. This paper discusses how it can be integrated into day-ahead energy markets and especially on what pricing schemes should be used to ensure an efficient and fair market.

  18. Demand side management in a day-ahead wholesale market: A comparison of industrial & social welfare approaches

    International Nuclear Information System (INIS)

    Highlights: • We compare two demand side management in a day-ahead electricity wholesale market. • We develop and reconcile social welfare & industrial DSM mathematical models. • We show the industrial netload has an additional forecast quantity of baseline. • We analytically and numerically show the model equivalence with accurate baseline. • We numerically demonstrate the baseline errors lead to higher and costlier dispatch. - Abstract: The intermittent nature of renewable energy has been discussed in the context of the operational challenges that it brings to electrical grid reliability. Demand side management (DSM) with its ability to allow customers to adjust electricity consumption in response to market signals has often been recognized as an efficient way to mitigate the variable effects of renewable energy as well as to increase system efficiency and reduce system costs. However, the academic & industrial literature have taken divergent approaches to DSM implementation. While the popular approach among academia adopts a social welfare maximization formulation, the industrial practice compensates customers according to their load reduction from a predefined electricity consumption baseline that would have occurred without DSM. This paper rigorously compares these two different approaches in a day-ahead wholesale market context analytically and in a test case using the same system configuration and mathematical formalism. The comparison of the two models showed that a proper reconciliation of the two models might make them mitigate the stochastic netload in fundamentally the same way, but only under very specific conditions which are rarely met in practice. While the social welfare model uses a stochastic net load composed of two terms, the industrial DSM model uses a stochastic net load composed of three terms including the additional baseline term. DSM participants are likely to manipulate the baseline in order to receive greater financial

  19. Class Schedules--Computer Loaded or Student Self-Scheduled?

    Science.gov (United States)

    Wall, Edward F.

    1979-01-01

    In the two-step process of student scheduling, the initial phase of course selection is the most important. At Chesterton High School in Indiana, student self-scheduling is preferred over computer loading. (Author/MLF)

  20. Day-Ahead Congestion Management in Distribution Systems through Household Demand Response and Distribution Congestion Prices

    DEFF Research Database (Denmark)

    Liu, Weijia; Wu, Qiuwei; Wen, Fushuan;

    2014-01-01

    into balancing power might challenge the operation of electric distribution systems and cause congestions. This paper presents a distribution congestion price (DCP) based market mechanism to alleviate possible distribution system congestions. By employing the loca- tional marginal pricing (LMP) model......, the proposed DCPs are able to reflect the real congestion cost and further direct the schedule of the responses of electric demands. Based on the NordPool Spot market structure, the interactions between aggregators and the distribution system operator (DSO) are discussed, and the procedure for calculating DCPs...

  1. Day ahead forecast of wind power through optimal application of multivariate analyzing methods

    Energy Technology Data Exchange (ETDEWEB)

    Arnoldt, Alexander; Bretschneider, Peter [Fraunhofer Institute for Optronics, System Technology, and Image Exploitation - Application Centre System Technology (IOSB-AST), Ilmenau (Germany). Energy Systems Group

    2011-07-01

    This paper presents two algorithms in identifying input models for artificial neural networks. The algorithms are based on an entropy analysis and an eigenvalue analysis of the correlation matrix. The resulting input models are used for investigating a feed forward and a recurrent artificial neural network structure to simulate a 24 hour forecast of wind power production. The limitation of the forecast error distribution is investigated through successful implementation of hybridization of single forecast models. Errors of the best forecast model stay between a normalized root mean square error from 3.5% to 6.1%. (orig.)

  2. Day-ahead load forecast using random forest and expert input selection

    International Nuclear Information System (INIS)

    Highlights: • A model based on random forests for short term load forecast is proposed. • An expert feature selection is added to refine inputs. • Special attention is paid to customers behavior, load profile and special holidays. • The model is flexible and able to handle complex load signal. • A technical comparison is performed to assess the forecast accuracy. - Abstract: The electrical load forecast is getting more and more important in recent years due to the electricity market deregulation and integration of renewable resources. To overcome the incoming challenges and ensure accurate power prediction for different time horizons, sophisticated intelligent methods are elaborated. Utilization of intelligent forecast algorithms is among main characteristics of smart grids, and is an efficient tool to face uncertainty. Several crucial tasks of power operators such as load dispatch rely on the short term forecast, thus it should be as accurate as possible. To this end, this paper proposes a short term load predictor, able to forecast the next 24 h of load. Using random forest, characterized by immunity to parameter variations and internal cross validation, the model is constructed following an online learning process. The inputs are refined by expert feature selection using a set of if–then rules, in order to include the own user specifications about the country weather or market, and to generalize the forecast ability. The proposed approach is tested through a real historical set from the Tunisian Power Company, and the simulation shows accurate and satisfactory results for one day in advance, with an average error exceeding rarely 2.3%. The model is validated for regular working days and weekends, and special attention is paid to moving holidays, following non Gregorian calendar

  3. Optimal operational strategies for a day-ahead electricity market in the presence of market power using multi-objective evolutionary algorithms

    Science.gov (United States)

    Rodrigo, Deepal

    2007-12-01

    This dissertation introduces a novel approach for optimally operating a day-ahead electricity market not only by economically dispatching the generation resources but also by minimizing the influences of market manipulation attempts by the individual generator-owning companies while ensuring that the power system constraints are not violated. Since economic operation of the market conflicts with the individual profit maximization tactics such as market manipulation by generator-owning companies, a methodology that is capable of simultaneously optimizing these two competing objectives has to be selected. Although numerous previous studies have been undertaken on the economic operation of day-ahead markets and other independent studies have been conducted on the mitigation of market power, the operation of a day-ahead electricity market considering these two conflicting objectives simultaneously has not been undertaken previously. These facts provided the incentive and the novelty for this study. A literature survey revealed that many of the traditional solution algorithms convert multi-objective functions into either a single-objective function using weighting schemas or undertake optimization of one function at a time. Hence, these approaches do not truly optimize the multi-objectives concurrently. Due to these inherent deficiencies of the traditional algorithms, the use of alternative non-traditional solution algorithms for such problems has become popular and widely used. Of these, multi-objective evolutionary algorithms (MOEA) have received wide acceptance due to their solution quality and robustness. In the present research, three distinct algorithms were considered: a non-dominated sorting genetic algorithm II (NSGA II), a multi-objective tabu search algorithm (MOTS) and a hybrid of multi-objective tabu search and genetic algorithm (MOTS/GA). The accuracy and quality of the results from these algorithms for applications similar to the problem investigated here

  4. Not All Large Customers are Made Alike: Disaggregating Response toDefault-Service Day-Ahead Market Pricing

    Energy Technology Data Exchange (ETDEWEB)

    Hopper, Nicole; Goldman, Charles; Neenan, Bernie

    2006-05-12

    For decades, policymakers and program designers have gone onthe assumption that large customers, particularly industrial facilities,are the best candidates for realtime pricing (RTP). This assumption isbased partly on practical considerations (large customers can providepotentially large load reductions) but also on the premise thatbusinesses focused on production cost minimization are most likely toparticipate and respond to opportunities for bill savings. Yet fewstudies have examined the actual price response of large industrial andcommercial customers in a disaggregated fashion, nor have factors such asthe impacts of demand response (DR) enabling technologies, simultaneousemergency DR program participation and price response barriers been fullyelucidated. This second-phase case study of Niagara Mohawk PowerCorporation (NMPC)'s large customer RTP tariff addresses theseinformation needs. The results demonstrate the extreme diversity of largecustomers' response to hourly varying prices. While two-thirdsexhibitsome price response, about 20 percent of customers provide 75-80 percentof the aggregate load reductions. Manufacturing customers are mostprice-responsive as a group, followed by government/education customers,while other sectors are largely unresponsive. However, individualcustomer response varies widely. Currently, enabling technologies do notappear to enhance hourly price response; customers report using them forother purposes. The New York Independent System Operator (NYISO)'semergency DR programs enhance price response, in part by signaling tocustomers that day-ahead prices are high. In sum, large customers docurrently provide moderate price response, but there is significant roomfor improvement through targeted programs that help customers develop andimplement automated load-response strategies.

  5. Day-ahead price forecasting of electricity markets by a new feature selection algorithm and cascaded neural network technique

    International Nuclear Information System (INIS)

    With the introduction of restructuring into the electric power industry, the price of electricity has become the focus of all activities in the power market. Electricity price forecast is key information for electricity market managers and participants. However, electricity price is a complex signal due to its non-linear, non-stationary, and time variant behavior. In spite of performed research in this area, more accurate and robust price forecast methods are still required. In this paper, a new forecast strategy is proposed for day-ahead price forecasting of electricity markets. Our forecast strategy is composed of a new two stage feature selection technique and cascaded neural networks. The proposed feature selection technique comprises modified Relief algorithm for the first stage and correlation analysis for the second stage. The modified Relief algorithm selects candidate inputs with maximum relevancy with the target variable. Then among the selected candidates, the correlation analysis eliminates redundant inputs. Selected features by the two stage feature selection technique are used for the forecast engine, which is composed of 24 consecutive forecasters. Each of these 24 forecasters is a neural network allocated to predict the price of 1 h of the next day. The whole proposed forecast strategy is examined on the Spanish and Australia's National Electricity Markets Management Company (NEMMCO) and compared with some of the most recent price forecast methods. (author)

  6. Day-Ahead Coordination of Vehicle-to-Grid Operation and Wind Power in Security Constraints Unit Commitment (SCUC

    Directory of Open Access Journals (Sweden)

    Mohammad Javad Abdollahi

    2015-08-01

    Full Text Available In this paper security constraints unit commitment (SCUC in the presence of wind power resources and electrical vehicles to grid is presented. SCUC operation prepare an optimal time table for generation unit commitment in order to maximize security, minimize operation cost and satisfy the constraints of networks and units in a period of time, as one of the most important research interest in power systems. Today, the relationship between power network and energy storage systems is interested for many researchers and network operators. Using Electrical Vehicles (PEVs and wind power for energy production is one of the newest proposed methods for replacing fossil fuels.One of the effective strategies for analyzing of the effects of Vehicle 2 Grid (V2G and wind power in optimal operation of generation is running of SCUC for power systems that are equipped with V2G and wind power resources. In this paper, game theory method is employed for deterministic solution of day-ahead unit commitment with considering security constraints in the simultaneous presence of V2G and wind power units. This problem for two scenarios of grid-controlled mode and consumer-controlled mode in three different days with light, medium and heavy load profiles is analyzed. Simulation results show the effectiveness of the presence of V2G and wind power for decreasing of generation cost and improving operation indices of power systems.

  7. Economic impact of price forecasting inaccuracies on self-scheduling of generation companies

    Energy Technology Data Exchange (ETDEWEB)

    Mohammadi-Ivatloo, B.; Ehsan, M. [Center of Excellence in Power System Management and Control, Department of Electrical Engineering, Sharif University of Technology, Tehran (Iran, Islamic Republic of); Zareipour, H. [Power and Energy Systems Group, Department of Electrical and Computer Engineering, University of Calgary, Alberta (Canada); Amjady, N. [Department of Electrical Engineering, University of Semnan, Semnan (Iran, Islamic Republic of)

    2011-02-15

    This paper studies the economic impact of using inaccurate price forecasts on self-scheduling of generation companies (GenCos) in a competitive electricity market. Four alternative sets of price forecasts are used in this study which have different levels of accuracy. The economic impact of price forecast inaccuracies is calculated by comparing the economic benefits of the GenCos in two self-scheduling scenarios. In the first scenario, electricity market price forecasts are used to optimally schedule the GenCos' next day operation. In the second scenario, perfect price forecasts, i.e., actual market prices, are used for self-scheduling of the GenCos. Two indices are utilized to quantify the differences in the economic benefits of the GenCos under the two scenarios. Simulation results are provided and discussed for two typical and inherently different GenCos, i.e., a hydro-based producer and a thermal-based producer. (author)

  8. Day-Ahead Reactive Power Scheduling for Distribution Network Considering Coordination of Distributed Generation With Capacitors%计及分布式电源与电容器协调的配电网日前无功计划

    Institute of Scientific and Technical Information of China (English)

    谭煌; 张璐; 丛鹏伟; 唐巍; 耿光飞; 杨德昌; 李绚丽

    2014-01-01

    针对目前含分布式电源(distributed generation,DG)的配电网中未考虑电容器补偿容量和 DG 无功出力协调调度的问题,研究了考虑 DG 与电容器组协调的无功优化方法。以网损和电压偏移满意度最高为目标,构建含DG的配电网日前动态无功优化调度模型。根据DG无功出力和电容器补偿的特点,提出 DG 和电容器协调的日前无功计划方法。分析了各类DG的无功出力极限并作为约束条件,对电容器和DG进行整体静态优化得到电容器的投切容量曲线;其次采用模糊聚类对电容器投切曲线进行时序分段并融合,制定电容器的日前计划;最后,在电容器补偿容量确定后,以DG作为优化变量,制定DG出力的日前计划。仿真结果验证了所提方法的有效性。%In allusion to the situation that in present distribution networks containing distributed generation (DG) the coordinated dispatching of the compensating capacity of capacitors with reactive output of DG is not taken into account, a reactive power optimization method considering the coordination of capacitor banks with DG is researched. Taking the highest satisfaction degree of both network loss and voltage deviation as the objective, an optimal day-ahead dynamic reactive power scheduling model for distribution network containing DG is constructed. Based on the reactive power output of DG and the features of capacitor compensation, a day-ahead reactive power scheduling that coordinates the DG with capacitor banks is proposed. Firstly, the limits of various DG’s reactive power output are analyzed and taken as constraints, the overall static state optimization of DG and capacitor banks is performed to attain the switching on/off capacity curve of capacitor banks; then fuzzy clustering is adapted to segment the capacity curve and subsection integration is used to formulate the day ahead schedule of capacitors;finally, after the determination of

  9. Self-scheduling and bidding strategies of thermal units with stochastic emission constraints

    International Nuclear Information System (INIS)

    Highlights: • The management of thermal power plants is considered for different emission allowance levels. • The uncertainty on electricity price is considered by a set of scenarios. • A stochastic MILP approach allows devising the bidding strategies and hedging against price uncertainty and emission allowances. - Abstract: This paper is on the self-scheduling problem for a thermal power producer taking part in a pool-based electricity market as a price-taker, having bilateral contracts and emission-constrained. An approach based on stochastic mixed-integer linear programming approach is proposed for solving the self-scheduling problem. Uncertainty regarding electricity price is considered through a set of scenarios computed by simulation and scenario-reduction. Thermal units are modelled by variable costs, start-up costs and technical operating constraints, such as: forbidden operating zones, ramp up/down limits and minimum up/down time limits. A requirement on emission allowances to mitigate carbon footprint is modelled by a stochastic constraint. Supply functions for different emission allowance levels are accessed in order to establish the optimal bidding strategy. A case study is presented to illustrate the usefulness and the proficiency of the proposed approach in supporting biding strategies

  10. Two-stage stochastic day-ahead optimal resource scheduling in a distribution network with intensive use of distributed energy resources

    DEFF Research Database (Denmark)

    Sousa, Tiago; Ghazvini, Mohammad Ali Fotouhi; Morais, Hugo;

    2015-01-01

    The integration of renewable sources and electric vehicles will introduce new uncertainties to the optimal resource scheduling, namely at the distribution level. These uncertainties are mainly originated by the power generated by renewables sources and by the electric vehicles charge requirements....... This paper proposes a two-state stochastic programming approach to solve the day-ahead optimal resource scheduling problem. The case study considers a 33-bus distribution network with 66 distributed generation units and 1000 electric vehicles.......The integration of renewable sources and electric vehicles will introduce new uncertainties to the optimal resource scheduling, namely at the distribution level. These uncertainties are mainly originated by the power generated by renewables sources and by the electric vehicles charge requirements...

  11. With 1,670 Students--Student Self-Scheduling Works Well for Us

    Science.gov (United States)

    Wall, F. Edward

    1976-01-01

    Chesterton High School, which has used both computer scheduling and student self-scheduling, finds the latter method produces the most satisfactory results. In response to Richard Tilwick's article in the November 1975 Bulletin (Student Self-Scheduling: An Unintentional Deception), F. Edward Wall explains why his students and teachers favor…

  12. Investigation by CRE into record high electricity prices on Powernext Day-ahead Auction in October and November 2007. Analysis report

    International Nuclear Information System (INIS)

    In October and November 2007, electricity prices hit record highs on the Powernext Day-Ahead Auction trading platform. While, during the first nine months of the year, prices for delivery between 6 pm and 8 pm averaged euros 36 /MWh, rising to a maximum of euros 118 /MWh, they spiked at: - euros 1,236 /MWh for delivery on Monday, 29 October 2007 between 6 pm and 7 pm; - euros 2,500 /MWh for delivery on Monday, 12 November 2007 between 8 pm and 9 pm; - euros 1,762 /MWh for delivery on Thursday, 15 November 2007 between 6 pm and 7 pm. Day ahead prices of electricity have a major effect on the procurement costs of suppliers, and consequently on the formation of selling prices to end consumers. Article 28 of French Act No.2000-108 of 10 February 2000 stipulates that CRE 'shall monitor, for electricity and natural gas, all transactions made between suppliers, brokers and producers, all transactions made on the organised markets and cross-border trading. It shall ensure that bids made by suppliers, brokers and producers are consistent with their financial and technical requirements'. Article 33 of the same Act specifies that, 'In performing the tasks entrusted to it, the French Energy Regulatory Commission (CRE) may gather any information it requires from the Ministers for the Economy and for Energy, from public electricity transmission and distribution system operators, from operators of infrastructures for the natural gas transmission and distribution networks and operators of liquefied natural gas facilities, as well as from any other company involved in the electricity and natural gas market. It may also call upon any person whose evidence it deems necessary for the purposes of its investigations'. In this context, and in application of its duty to monitor the electricity wholesale markets, CRE has undertaken an investigation to analyse the mechanisms underlying the formation of such high prices. To this end, CRE gathered information relative to decisions taken by

  13. 主动型配电网日前调度策略研究%Study on day-ahead dispatch strategy of active distribution network

    Institute of Scientific and Technical Information of China (English)

    窦震海; 牛焕娜; 高燕; 杨明皓; 杨仁刚

    2014-01-01

    /low voltage distribution network, electricity sales of the power company are bound to decrease and operating income will accordingly be reduced, which is an avoided problem in previous research. All scheduling models proposed in the studies are based on the goal of the lowest supply power cost, and are not concerned with who gets the operating income. However, this is the most significant problem of power companies. In this paper, a novel day-ahead scheduling model of active distribution network is supposed. The goal of this model is maximizing the profit of the power company. And it is more objectively described as purchase power costs and sale power revenues of Chinese power companies with an active distribution network. Moreover, this model takes into account the various power prices of different distributed power, the incentive policies of government and government subsidies of the power company. More importantly, because the network losses of distribution lines in high voltage network before the inlet of medium voltage distribution network is correlated strongly with its electrical distance. This model accounts for the profit of the power company which network losses are reduced owing to use of distribute power and micro-grid. Using this model, the active medium voltage distribution networks are scheduled in different locations, which not only can achieve greater efficiency of power companies through accessing the distribute power and micro-grid at the location away from the main network, but also don’t face losses in close supply power with the new energy accesses through reasonable scheduling. In this paper, examples of IEEE33 node demonstrate the effectiveness and feasibility of the model. The results can provide a reference for optimization scheduling of the active distribution network.%相对于传统配电网,主动型配电网可以合理利用其双向调度功能,充分发挥分布式发电容量,在保护环境的同时还可以提高电力公司的效

  14. Self-scheduled LPV controller synthesis for doubly-fed induction generators

    NARCIS (Netherlands)

    Nguyen Tien, H.; Scherer, C.W.; Scherpen, J.M.A.

    2007-01-01

    This paper presents a new current control design for doubly-fed induction generators in wind turbine systems, where the control is implemented on the rotor side. The mechanical angular speed of the rotor is considered as a time-varying parameter. A self-scheduled controller is then designed for the

  15. 低碳经济下风火互济系统日前发电计划模式分析%Day-ahead Dispatch Mode for Wind-thermal Power System in Low-carbon Economy

    Institute of Scientific and Technical Information of China (English)

    王彩霞; 乔颖; 鲁宗相; 徐飞

    2011-01-01

    Wind power is one of the most competitive low-carbon energy resources,and is an important element in promoting low-carbon economy.With the output characteristics of wind power generators and its low-carbon emission in mind,the coordination between wind power generators and conventional thermal power generators is analyzed.CO2 price signal is introduced and the integrated optimization model is constructed for wind-thermal power systems.Five day-ahead dispatch modes are proposed,which are different from each other in terms of the principle of wind power utilization,day-ahead schedule objective,and ways of wind power participation into day-ahead scheduling.They are compared in a typical wind-thermal power system,with designated system performance indices.Impact of different CO2 prices and wind power penetration levels are also analyzed.Simulation results show that wind power priority dispatch with a certain amount of curtailment improves the system performance significantly compared with dispatch that discourages wind power curtailment;Day-ahead dispatch that optimizes both system economy and environmental benefits is better than the conventional mode that is aimed at system economy only;At proper CO2 prices,equal participation of wind power with conventional generators is the best way of optimization in achieving both system economy and environmental benefits.%风电是最具竞争力的低碳能源之一,是推动低碳经济发展的重要力量。考虑风电机组出力特点,关注风电低碳效益的发挥,研究了风电机组与火电机组协调运行的问题。通过引入CO2价格指标,建立了风火互济系统运行的综合最优模型。从风能利用原则、日前发电计划优化目标、风电参与日前调度的方式3个方面提出了含风电的5种典型日前发电计划模型。在典型风火互济系统中对各模式进行了比较,并深入讨论了CO2价格、不同风电接入水平对模型的影响。结果表明,优先调度

  16. Experimental validation of a real time energy management system for microgrids in islanded mode using a local day-ahead electricity market and MINLP

    International Nuclear Information System (INIS)

    Highlights: • An algorithm is developed to enhance Microgrid performance. • Local energy market cost model is proposed to obtain the cheapest price. • Several real technical and market scenarios are considered in the study. • Simulation and experimental results demonstrate a significant reduction in cost. - Abstract: Energy management systems (EMS) are vital supervisory control tools used to optimally operate and schedule Microgrids (MG). In this paper, an EMS algorithm based on mixed-integer nonlinear programming (MINLP) is presented for MG in islanding mode considering different scenarios. A local energy market (LEM) is also proposed with in this EMS to obtain the cheapest price, maximizing the utilization of distributed energy resources. The proposed energy management is based on LEM and allows scheduling the MG generation with minimum information shared sent by generation units. Load demand management is carried out by demand response concept to improve reliability and efficiency as well as to reduce the total cost of energy (COE). Simulations are performed with real data to test the performance and accuracy of the proposed algorithm. The proposed algorithm is experimentally tested to evaluate processing speed as well as to validate the results obtained from the simulation setup on a real MG Testbed. The results of the EMS–MINLP based on LEM are compared with a conventional EMS based on LEM. Simulation and experimental results show the effectiveness of the proposed algorithm which provides a reduction of 15% in COE, in comparison with conventional EMS

  17. A day-ahead evaluation method and application on acceptance ability of power grid for new energy power generation%新能源接纳能力日前评估方法及应用

    Institute of Scientific and Technical Information of China (English)

    韩红卫

    2014-01-01

    针对宁夏电网新能源发展现状及新能源调度面临的问题,分析了新能源接纳能力对新能源调度的重要作用。通过拓展安全约束经济调度(SCED)模型的应用,提出了一种分区域评估主要新能源接入地区和电网日前新能源接纳能力的方法。应用结果表明:在新能源无法全额消纳的情况下,该方法能够有效避免新能源限电过程中产生的厂网矛盾,提高日前调度计划的实用性及可靠性,为电网的安全稳定运行提供可靠保障。%Aiming at the development status quo and the problem of dispatch of new energy power generation,analyzes the important role of new energy power generation on scheduling. By expanding application of the security constrained economic dispatch(SCED)model,puts forward the method to evaluating the main acceptance area and acceptance ability of new energy. The application result shows that under the condition of the new energy can not be accepted in full,the method can avoid the illogicality to take place between wind generating plant and power grid in the process of power rationing,increase practicability and reliability of a day-ahead scheduling plan,provide credibility for power grid safe and stable operation.

  18. Weekly self-scheduling, forward contracting, and pool involvement for an electricity producer: an adaptive robust optimization approach

    OpenAIRE

    Ricardo M. Lima; Novais, Augusto Q.; Conejo, Antonio J.

    2015-01-01

    his paper addresses the optimization under uncertainty of the self-scheduling, forward contracting, and pool involvement of an electricity producer operating a mixed power generation station, which combines thermal, hydro and wind sources, and uses a two stage adaptive robust optimization approach. In this problem the wind power production and the electricity pool price are considered to be uncertain, and are described by uncertainty convex sets. To solve this problem, two variants of a const...

  19. 用户互动负荷模型及其微电网日前经济调度的应用%An Interaction Load Model and Its Application in Microgrid Day-Ahead Economic Scheduling

    Institute of Scientific and Technical Information of China (English)

    孙川; 汪隆君; 许海林

    2016-01-01

    1An interaction load model was established, including shiftable, curtailable and transferable loads, applied in microgrid day-ahead economic scheduling under interaction environment. Firstly, the proposed model for shiftable load was described with integer variable and power distribution vector immensely reducing model scale. Secondly, involved model for curtailable load considers interaction frequency and duration. Thirdly, the model for transferable load regards transferable timespan. Even more important, the model remains linear. As a result, its solution is independent of initial points when solved with an optimization solver. Contents of customer interaction contract were discussed. A case study was performed to verify the proposed model. Numerical results demonstrate that 1) the proposed model, taking features and requirements of interaction load into sufficient account, is of maneuverability;2) curtailable load is able to shave load peak, while shiftable and transferable loads can shift peak; 3) 3 types of interaction loads coordinate with each other, not only adjusting load curve reasonably, but also accommodating renewable energy in a way of realizing economic operation of whole system.%建立了可平移负荷、可削减负荷和可转移负荷3类互动负荷模型,应用于用户参与互动环境下微电网日前经济调度,并探讨了用户互动合约的相关内容。可平移负荷模型通过0-1变量和功率分布向量描述,极大地降低了模型求解规模;可削减负荷模型考虑了互动频率和持续时间;可转移负荷模型考虑了可转移时间区间;互动负荷模型均保持线性,求解不依赖于初值。算例验证结果表明:1)所提出的模型充分考虑了互动负荷的用电特点和用户要求,工程实操性强;2)可削减负荷能发挥削峰作用,可平移负荷和可转移负荷实现移峰;3)3类互动负荷相互配合,不仅能合理调整负荷曲线,还能有

  20. MASCEM: EPEX SPOT Day-Ahead market integration and simulation

    DEFF Research Database (Denmark)

    Santos, Gabriel; Fernandes, Ricardo; Pinto, Tiago;

    2015-01-01

    The energy sector restructuring process in industrialized countries had the aim of reducing electricity prices by increasing competitiveness, and facilitate the integration of distributed energy resources. However, the complexity in market players' interactions has increased, and new problems hav...

  1. The Power of Weather: Some Empirical Evidence on Predicting Day-ahead Power Prices through Day-ahead Weather Forecasts

    NARCIS (Netherlands)

    F. Ravazzolo (Francesco); C. Zhou (Chen); C. Huurman

    2007-01-01

    textabstractIn the literature the effects of weather on electricity sales are well-documented. However, studies that have investigated the impact of weather on electricity prices are still scarce (e.g. Knittel and Roberts, 2005), partly because the wholesale power markets have only recently been der

  2. Powernext Day-Ahead. Powernext Futures. Activity report - 2004; Powernext Day-Ahead. Powernext Futures. Bilan statistique 2004

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-07-01

    Powernext SA is a Multilateral Trading Facility which organizes and warrants the transactions on the European power exchange market. This activity report presents the highlights of the market and of Powernext in 2004: market conditions (more reasonable and less volatile prices, steadier market conditions (climate conditions, power consumption, correlation between French and German prices), increasing liquidity, start-up of Powernext Futures{sup TM} for medium-term contracts and introduction of futures price curve, promising volumes to start, and liquidity of the futures market. (J.S)

  3. Electricity price forecasting using generalized regression neural network based on principal components analysis

    Institute of Scientific and Technical Information of China (English)

    牛东晓; 刘达; 邢棉

    2008-01-01

    A combined model based on principal components analysis (PCA) and generalized regression neural network (GRNN) was adopted to forecast electricity price in day-ahead electricity market. PCA was applied to mine the main influence on day-ahead price, avoiding the strong correlation between the input factors that might influence electricity price, such as the load of the forecasting hour, other history loads and prices, weather and temperature; then GRNN was employed to forecast electricity price according to the main information extracted by PCA. To prove the efficiency of the combined model, a case from PJM (Pennsylvania-New Jersey-Maryland) day-ahead electricity market was evaluated. Compared to back-propagation (BP) neural network and standard GRNN, the combined method reduces the mean absolute percentage error about 3%.

  4. Research of Day-ahead Environmental Protection Dispatch in Carbon Capture Systems Using a-superquantile Method%采用α超分位数方法的含碳捕集系统日前环保调度研究

    Institute of Scientific and Technical Information of China (English)

    范文帅; 张斌; 陈驾宇

    2012-01-01

    According to the safe operation in power system, the change of carbon capture power plant output caused by the flucamtion of carbon price is researched by cost index of the purchase of carbon emission fights. The relationship between carbon price and the level of cadxm capture is reflected by using price elasticity of demand theory in economics, α-superquantile theory is introduced to quantify the uncertain output of carbon capture power plant, Taking day-ahead energyg and environment-protective as objective, the model of daily environmental protection dispatch in cadxm capture power plant integrated system is conslructeck The example on IEEE30 system show that under different confidence levels and different αuantile constraints of carbon emissions, the proposed model can achieve optimal dispatching results in each period that emphasize on environment or economy.%从电力系统安全运行的角度出发,利用购买碳排放权成本指标,研究了碳价波动引起碳捕集电厂出力变化的问题。根据经济学的需求价格弹性原理来反映碳价与碳捕集水平之间的关系,并引入α-超分位数理论来度量碳捕集电厂出力的不确定性,以日前节能环保为目标,构建了碳捕集电厂的电力系统目前环保调度模型。IEEE30节点系统算例表明,采用α-超分位数约束的含碳捕集系统日前环保调度,可在不同置信水平和不同碳捕集电厂碳排放量的α-超分位数约束下,获取侧重环保性或经济性的系统各时段最优调度方案。

  5. 75 FR 42380 - Orders Finding That the SP-15 Financial Day-Ahead LMP Peak Contract and SP-15 Financial Day-Ahead...

    Science.gov (United States)

    2010-07-21

    ... of agreements, contracts or transactions in a commodity being traded on the electronic trading... transactions executed on ICE's electronic platform in the SPM contract was 3,235 in the second quarter of 2009... transaction executed on its trading platform and that created by a transaction executed off its...

  6. 通过电动汽车与电网互动减少弃风的商业模式与日前优化调度策略%Business Model and Day-ahead Dispatch Strategy to Reduce Wind Power Curtailment Through Vehicle-to-Grid

    Institute of Scientific and Technical Information of China (English)

    项顶; 胡泽春; 宋永华; 丁华杰

    2015-01-01

    电动汽车接受运营商调控参与车网互动(vehicle-to-grid,V2G)能够更好地与间歇性新能源发电相配合,从而创造巨大的经济效益和社会效益,而这种V2G模式需要相应的商业模式作为支撑.通过分析受控电动汽车的特征,提出电动汽车用户、运营商(Aggregator)、电网公司和弃风电场合作的V2G商业合同模式.建立以运营商期望收益最大化为目标,以满足用户个体需求和电费补偿约束,考虑弃风功率限制、机组调节速率限制的运营商日前优化调度模型.提出了针对所建非线性混合整数规划问题的求解算法.以京津唐电网为例,验证了所提合同模式、调度策略及求解算法的有效性和准确性.%Vehicle-to-Grid (V2G) under the management of electric vehicle (EV) aggregators has great potential to interact with renewable energy generation. This interactive mode could create enormous economic and social benefits, however, it lacks appropriate business model as a support. In this paper, a business model based on cooperation among EV users, aggregators, electric companies and wind farms was proposed. Under constraints of EV users' charging demand and discharging compensation, curtailed wind power profile and unit ramp rate, aday-ahead optimal scheduling formulation for aggregators to maximize their expected revenue was established. An algorithm which can solve this kind of nonlinear mixed integer programming problem was also proposed. Simulation based on data from the Beijing- Tianjin-Tangshan power grid is conducted and the results prove the effectiveness of the proposed business and scheduling models and the accuracy of proposed algorithm.

  7. 面向大容量风电接入考虑用户侧互动的系统日前调度和运行模拟研究%Day-ahead Generation Scheduling and Operation Simulation Considering Demand Response in Large-capacity Wind Power Integrated Systems

    Institute of Scientific and Technical Information of China (English)

    王蓓蓓; 刘小聪; 李扬

    2013-01-01

    The stochastic fluctuations of wind increase the difficulty in operating scheduling in power system. This paper established a generation scheduling model and operation simulation model considering demand response in large-capacity wind power integrated system. In the model reserve cost for wind power was incorporated into objective function and up spinning reserve and down spinning reserve were considered. Load curve was predicted according to user response principle based on consumer psychology and interrupted load acted as part of system reserve. The effectiveness of TOU and IL was integrated into one model on account of coordinating generate and demand side, which could respond to characteristic of negative peaking load shifting intermittency of wind power. The wind energy curtailment and loss of load before and after considering demand side response under varieties of wind power outputs were estimated by Monte Carlo simulation. The relationship between wind power penetration and wind energy curtailment and the one between wind power capacity and loss of load were presented in this paper. The simulation on IEEE 24-bus system indicated this model can decrease the generating cost effectively and increase utilization ratio and levels of capacity usage of wind power.%  风电的随机波动性增大了系统调度的难度,将需求响应融入传统发电日前调度计划,将风电备用成本纳入目标函数,同时增加了正负旋转备用约束。以基于消费者心理学的分时电价用户响应原理预测负荷曲线,将可中断负荷作为部分系统备用,建立面向大容量风电接入考虑用户侧互动的系统日前调度模型和运行模拟模型。综合考虑发用电侧资源,将分时电价和可中断负荷这两种需求响应措施融入同一模型,用于应对风电的反调峰特性和间歇性。采用蒙特卡洛算法模拟多种风电出力的情况,评估考虑用户侧互动前后系统的弃风量和

  8. Estimating the revenues of a hydrogen-based high-capacity storage device: methodology and results

    OpenAIRE

    François-Lavet, Vincent; Fonteneau, Raphaël; Ernst, Damien

    2014-01-01

    This paper proposes a methodology to estimate the maximum revenue that can be generated by a company that operates a high-capacity storage device to buy or sell electricity on the day-ahead electricity market. The methodology exploits the Dynamic Programming (DP) principle and is specified for hydrogen-based storage devices that use electrolysis to produce hydrogen and fuel cells to generate electricity from hydrogen. Experimental results are generated using historical data of energy prices o...

  9. Day-ahead deregulated electricity market price forecasting using neural network input featured by DCT

    International Nuclear Information System (INIS)

    Highlights: • We presented DCT input featured FFNN model for forecasting in Spain market. • The key factors impacting electricity price forecasting are historical prices. • Past 42 days were trained and the next 7 days were forecasted. • The proposed approach has a simple and better NN structure. • The DCT-FFNN mode is effective and less computation time than the recent models. - Abstract: In a deregulated market, a number of factors determined the outcome of electricity price and displays a perplexed and maverick fluctuation. Both power producers and consumers needs single compact and robust price forecasting tool in order to maximize their profits and utilities. In order to achieve the helter–skelter kind of electricity price, one dimensional discrete cosine transforms (DCT) input featured feed-forward neural network (FFNN) is modeled (DCT-FFNN). The proposed FFNN is a single compact and robust architecture (without hybridizing the various hard and soft computing models). It has been predicted that the DCT-FFNN model is close to the state of the art can be achieved with less computation time. The proposed DCT-FFNN approach is compared with 17 other recent approaches to estimate the market clearing prices of mainland Spain. Finally, the accuracy of the price forecasting is also applied to the electricity market of New York in year 2010 that shows the effectiveness of the proposed DCT-FFNN approach

  10. Day-ahead prediction using time series partitioning with Auto-Regressive model

    Directory of Open Access Journals (Sweden)

    Dennis Cheruiyot Kiplangat

    2016-08-01

    Full Text Available Wind speed forecasting has received a lot of attention in the recent past from researchers due to its enormous benefits in the generation of wind power and distribution. The biggest challenge still remains to be accurate prediction of wind speeds for efficient operation of a wind farm. Wind speed forecasts can be greatly improved by understanding its underlying dynamics. In this paper, we propose a method of time series partitioning where the original 10 minutes wind speed data is converted into a twodimensional array of order (N x 144 where N denotes the number of days with 144 the daily 10-min observations. Upon successful time series partitioning, a point forecast is computed for each of the 144 datasets extracted from the 10 minutes wind speed observations using an Auto-Regressive (AR process which is then combined together to give the (N+1st day forecast. The results of the computations show significant improvement in the prediction accuracy when AR model is coupled with time series partitioning.

  11. New approach to bidding strategies of generating companies in day ahead energy market

    International Nuclear Information System (INIS)

    In the restructured power systems, generating companies (Genco) are responsible for selling their product in the energy market. In this condition, the question is how much and for what price must each Genco generate to maximize its profit. Therefore, this paper intends to propose a rational method to answer this question. In the proposed methodology, the hourly forecasted market clearing price (FMCP) is used as a reference to model the possible and probable price strategies of Gencos. The forecasted price is the basis of the bidding strategies of each Genco, which can be achieved by solving a bi-level optimization problem using GAMS (general algebraic modeling system) language. The first level, called upper sub-problem is used to maximize the individual Genco's payoffs for obtaining the optimal offered quantity of Gencos. The second one, hereafter called the lower sub-problem uses the results of the upper sub-problem and minimizes the consumer's payment with regard to the technical and network constraints, which leads to the awarded generation of the Gencos. Similar to the other game problems, the Nash equilibrium strategies are the optimum bidding strategies of Gencos. A six bus system is employed to illustrate the application of the proposed method and to show its high precision and capabilities. (author)

  12. Day ahead price forecasting of electricity markets by a mixed data model and hybrid forecast method

    International Nuclear Information System (INIS)

    In a competitive electricity market, forecast of energy prices is a key information for the market participants. However, price signal usually has a complex behavior due to its nonlinearity, nonstationarity, and time variancy. In spite of all performed researches on this area in the recent years, there is still an essential need for more accurate and robust price forecast methods. In this paper, a combination of wavelet transform (WT) and a hybrid forecast method is proposed for this purpose. The hybrid method is composed of cascaded forecasters where each forecaster consists of a neural network (NN) and an evolutionary algorithms (EA). Both time domain and wavelet domain features are considered in a mixed data model for price forecast, in which the candidate input variables are refined by a feature selection technique. The adjustable parameters of the whole method are fine-tuned by a cross-validation technique. The proposed method is examined on PJM electricity market and compared with some of the most recent price forecast methods. (author)

  13. Optimal energy exchange of an industrial cogeneration in a day-ahead electricity market

    International Nuclear Information System (INIS)

    This paper addresses an optimal strategy for the daily energy exchange of a 22-MW combined-cycle cogeneration plant of an industrial factory operating in a liberalized electricity market. The optimization problem is formulated as a Mixed-Integer Linear Programming Problem (MILP) that maximizes the profit from energy exchange of the cogeneration, and is subject to the technical constraints and the industrial demand profile. The integer variables are associated with export or import of electricity whereas the real variables relate to the power output of gas and steam turbines, and to the electricity purchased from or sold to the market. The proposal is applied to a real cogeneration plant in Spain where the detailed cost function of the process is obtained. The problem is solved using a large-scale commercial package and the results are discussed and compared with different predefined scheduling strategies. (author)

  14. Day-Ahead Scheduling of a Photovoltaic Plant by the Energy Management of a Storage System

    DEFF Research Database (Denmark)

    Marinelli, Mattia; Sossan, Fabrizio; Isleifsson, Fridrik Rafn;

    2013-01-01

    The paper discusses and describes a system for energy management of a 10 kW PV plant coupled with a 15 kW - 190 kWh storage system. The overall idea is, by knowing the meteorological forecast for the next 24h, to dispatch the PV system and to be able to grant the scheduled hourly energy profile b...

  15. Day-ahead resource scheduling including demand response for electric vehicles

    DEFF Research Database (Denmark)

    Soares, Joao; Morais, Hugo; Sousa, Tiago;

    2014-01-01

    . Mixed integer non-linear programming is also used for comparison purposes. Full ac power flow calculation is included to allow taking into account the network constraints. A case study with a 33-bus distribution network and 2000 V2G resources is used to illustrate the performance of the proposed method....

  16. Using approximate dynamic programming for estimating the revenues of a hydrogen-based high-capacity storage device

    OpenAIRE

    François-Lavet, Vincent; Fonteneau, Raphaël; Ernst, Damien

    2014-01-01

    This paper proposes a methodology to estimate the maximum revenue that can be generated by a company that operates a high-capacity storage device to buy or sell electricity on the day-ahead electricity market. The methodology exploits the Dynamic Programming (DP) principle and is specified for hydrogen-based storage devices that use electrolysis to produce hydrogen and fuel cells to generate electricity from hydrogen. Experimental results are generated using historical data of energy prices o...

  17. FORECASTING RETURNS FOR THE STOCK EXCHANGE OF THAILAND INDEX USING MULTIPLE REGRESSION BASED ON PRINCIPAL COMPONENT ANALYSIS

    Directory of Open Access Journals (Sweden)

    Nop Sopipan

    2013-01-01

    Full Text Available The aim of this study was to forecast the returns for the Stock Exchange of Thailand (SET Index by adding some explanatory variables and stationary Autoregressive Moving-Average order p and q (ARMA (p, q in the mean equation of returns. In addition, we used Principal Component Analysis (PCA to remove possible complications caused by multicollinearity. Afterwards, we forecast the volatility of the returns for the SET Index. Results showed that the ARMA (1,1, which includes multiple regression based on PCA, has the best performance. In forecasting the volatility of returns, the GARCH model performs best for one day ahead; and the EGARCH model performs best for five days, ten days and twenty-two days ahead.

  18. Distinguishing high and low flow domains in urban drainage systems 2 days ahead using numerical weather prediction ensembles

    DEFF Research Database (Denmark)

    Courdent, Vianney Augustin Thomas; Grum, Morten; Mikkelsen, Peter Steen

    2016-01-01

    prediction (NWP) model subject to three different ensemble post-processing approaches can be used to forecast flow exceedance in a combined sewer for a wide range of ratios between the probability of detection (POD) and the probability of false detection (POFD). We use a hydrological rainfall-runoff model......Precipitation constitutes a major contribution to the flow in urban storm- and wastewater systems. Forecasts of the anticipated runoff flows, created from radar extrapolation and/or numerical weather predictions, can potentially be used to optimize operation in both wet and dry weather periods...... to transform the forecasted rainfall into forecasted flow series and evaluate three different approaches to establishing the relative operating characteristics (ROC) diagram of the forecast, which is a plot of POD against POFD for each fraction of concordant ensemble members and can be used to select...

  19. Price-Maker Wind Power Producer Participating in a Joint Day-Ahead and Real-Time Market

    DEFF Research Database (Denmark)

    Delikaraoglou, Stefanos; Papakonstantinou, Athanasios; Ordoudis, Christos;

    2015-01-01

    The large scale integration of stochastic renewable energy introduces significant challenges for power system operators and disputes the efficiency of the current market design. Recent research embeds the uncertain nature of renewable sources by modelling electricity markets as a two...... Constraints (MPEC) that is reformulated as a single-level Mixed-Integer Linear Program (MILP), which can be readily solved. Our analysis shows that adopting strategic behaviour may improve producer’s expected profit as the share of wind power increases. However, this incentive diminishes in power systems...... where available flexible capacity is high enough to ensure an efficient market operation....

  20. Pay-as-bid based reactive power market

    Energy Technology Data Exchange (ETDEWEB)

    Amjady, N. [Department of Electrical Engineering, Semnan University, Semnan (Iran, Islamic Republic of); Rabiee, A., E-mail: Rabiee@iust.ac.i [Center of Excellence for Power System Automation and Operation, Department of Electrical Engineering, Iran University of Science and Technology, Tehran (Iran, Islamic Republic of); Shayanfar, H.A. [Center of Excellence for Power System Automation and Operation, Department of Electrical Engineering, Iran University of Science and Technology, Tehran (Iran, Islamic Republic of)

    2010-02-15

    In energy market clearing, the offers are stacked in increasing order and the offer that intersects demand curve, determines the market clearing price (MCP). In reactive power market, the location of reactive power compensator is so important. A low cost reactive producer may not essentially be favorable if it is far from the consumer. Likewise, a high cost local reactive compensator at a heavily loaded demand center of network could be inevitably an alternative required to produce reactive power to maintain the integrity of power system. Given the background, this paper presents a day-ahead reactive power market based on pay-as-bid (PAB) mechanism. Generators expected payment function (EPF) is used to construct a bidding framework. Then, total payment function (TPF) of generators is used as the objective function of optimal power flow (OPF) problem to clear the PAB based market. The CIGRE-32 bus test system is used to examine the effectiveness of the proposed reactive power market.

  1. Mixed integer non-linear programming and Artificial Neural Network based approach to ancillary services dispatch in competitive electricity markets

    International Nuclear Information System (INIS)

    Highlights: • Ancillary services market management. • Ancillary services requirements forecast based on Artificial Neural Network. • Ancillary services clearing mechanisms without complex bids and with complex bids. - Abstract: Ancillary services represent a good business opportunity that must be considered by market players. This paper presents a new methodology for ancillary services market dispatch. The method considers the bids submitted to the market and includes a market clearing mechanism based on deterministic optimization. An Artificial Neural Network is used for day-ahead prediction of Regulation Down, regulation-up, Spin Reserve and Non-Spin Reserve requirements. Two test cases based on California Independent System Operator data concerning dispatch of Regulation Down, Regulation Up, Spin Reserve and Non-Spin Reserve services are included in this paper to illustrate the application of the proposed method: (1) dispatch considering simple bids; (2) dispatch considering complex bids

  2. Optimal Planning Strategy for Large PV/Battery System Based on Long-Term Insolation Forecasting

    Science.gov (United States)

    Yona, Atsushi; Uchida, Kosuke; Senjyu, Tomonobu; Funabashi, Toshihisa

    Photovoltaic (PV) systems are rapidly gaining acceptance as some of the best alternative energy sources. Usually the power output of PV system fluctuates depending on weather conditions. In order to control the fluctuating power output for PV system, it requires control method of energy storage system. This paper proposes an optimization approach to determine the operational planning of power output for PV system with battery energy storage system (BESS). This approach aims to obtain more benefit for electrical power selling and to smooth the fluctuating power output for PV system. The optimization method applies genetic algorithm (GA) considering PV power output forecast error. The forecast error is based on our previous works with the insolation forecasting at one day ahead by using weather reported data, fuzzy theory and neural network(NN). The validity of the proposed method is confirmed by the computer simulations.

  3. 75 FR 42411 - Orders Finding That the SP-15 Financial Day-Ahead LMP Peak Daily Contract; SP-15 Financial Day...

    Science.gov (United States)

    2010-07-21

    ... transactions in a commodity being traded on the electronic trading facility is sufficient to have a material... clearing. In this regard, ICE does not differentiate between open interest created by a transaction executed on its trading platform and that created by a transaction executed off its trading...

  4. Optimal bidding strategy of battery storage in power markets considering performance based regulation and battery cycle life

    DEFF Research Database (Denmark)

    He, Guannan; Chen, Qixin; Kang, Chongqing;

    2015-01-01

    Large-scale battery storage will become an essential part of the future smart grid. This paper investigates the optimal bidding strategy for battery storage in power markets. Battery storage could increase its profitability by providing fast regulation service under a performance-based regulation...... mechanism, which better exploits a battery’s fast ramping capability. However, battery life might be decreased by frequent charge–discharge cycling, especially when providing fast regulation service. It is profitable for battery storage to extend its service life by limiting its operational strategy to some...... degree. Thus, we incorporate a battery cycle life model into a profit maximization model to determine the optimal bids in day-ahead energy, spinning reserve, and regulation markets. Then a decomposed online calculation method to compute cycle life under different operational strategies is proposed...

  5. Wavelet-based Evapotranspiration Forecasts

    Science.gov (United States)

    Bachour, R.; Maslova, I.; Ticlavilca, A. M.; McKee, M.; Walker, W.

    2012-12-01

    Providing a reliable short-term forecast of evapotranspiration (ET) could be a valuable element for improving the efficiency of irrigation water delivery systems. In the last decade, wavelet transform has become a useful technique for analyzing the frequency domain of hydrological time series. This study shows how wavelet transform can be used to access statistical properties of evapotranspiration. The objective of the research reported here is to use wavelet-based techniques to forecast ET up to 16 days ahead, which corresponds to the LANDSAT 7 overpass cycle. The properties of the ET time series, both physical and statistical, are examined in the time and frequency domains. We use the information about the energy decomposition in the wavelet domain to extract meaningful components that are used as inputs for ET forecasting models. Seasonal autoregressive integrated moving average (SARIMA) and multivariate relevance vector machine (MVRVM) models are coupled with the wavelet-based multiresolution analysis (MRA) results and used to generate short-term ET forecasts. Accuracy of the models is estimated and model robustness is evaluated using the bootstrap approach.

  6. 不同时间尺度下基于混合储能调度的微网能量优化%Hybrid Energy Storage Scheduling Based Microgrid Energy Optimization Under Different Time Scales

    Institute of Scientific and Technical Information of China (English)

    刘方; 杨秀; 时珊珊; 张美霞; 邓虹; 郭鹏超

    2014-01-01

    According to different features of energy-based energy storage and power-based energy storage in hybrid energy storage system an economic optimization model of microgrid, which corresponds with actual demand, is established. Based on different time scales the day-ahead and real-time scheduling strategies are proposed. Considering poor prediction accuracy of day-ahead scheduling, using chance constrained programming and taking satisfying the demand on reserve under a certain confidence level as reliability constraint and taking the minimum operation cost as the optimization objective and utilizing the difference of TOU price the optimal coordination of the output of micro energy sources and energy storage systems are performed. In allusion to power fluctuation brought about by such uncertain factors as wind turbine, photovoltaic generation and load, in real-time scheduling the first-order low-pass filtering algorithm is applied to smooth the power fluctuation, and the moving average filtering method is utilized to reasonably allocate the post-filtering fluctuating power among hybrid energy storage systems to make the battery energy storage system taking on more low-frequency power fluctuation and the supercapacitor taking on high-frequency power fluctuation. The real-time scheduling is carried out according to day-ahead plan to monitor operating states of all units in real time and to modify the deviation of day-ahead plan caused by the cumulation of power fluctuation in time.%针对混合储能系统中能量型和功率型储能的不同特点,建立了符合实际需求的微网经济优化模型。根据不同时间尺度提出了日前调度策略和实时调度策略。考虑到日前调度预测精度差的弊端,应用机会约束规划,以一定置信水平下满足备用需求作为可靠性约束,将最小运行成本作为优化目标,利用分时电价差异,优化协调各微源和储能系统出力。针对微网内

  7. Virtual power plant mid-term dispatch optimization

    International Nuclear Information System (INIS)

    Highlights: ► Mid-term virtual power plant dispatching. ► Linear modeling. ► Mixed-integer linear programming applied to mid-term dispatch scheduling. ► Operation profit maximization combining bilateral contracts and the day-ahead market. -- Abstract: Wind power plants incur practically zero marginal costs during their operation. However, variable and uncertain nature of wind results in significant problems when trying to satisfy the contracted quantities of delivered electricity. For this reason, wind power plants and other non-dispatchable power sources are combined with dispatchable power sources forming a virtual power plant. This paper considers a weekly self-scheduling of a virtual power plant composed of intermittent renewable sources, storage system and a conventional power plant. On the one hand, the virtual power plant needs to fulfill its long-term bilateral contracts, while, on the other hand, it acts in the market trying to maximize its overall profit. The optimal dispatch problem is formulated as a mixed-integer linear programming model which maximizes the weekly virtual power plant profit subject to the long-term bilateral contracts and technical constraints. The self-scheduling procedure is based on stochastic programming. The uncertainty of the wind power and solar power generation is settled by using pumped hydro storage in order to provide flexible operation, as well as by having a conventional power plant as a backup. The efficiency of the proposed model is rendered through a realistic case study and analysis of the results is provided. Additionally, the impact of different storage capacities and turbine/pump capacities of pumped storage are analyzed.

  8. Six ways of providing base load power from wind

    International Nuclear Information System (INIS)

    This fact sheet discussed methods of providing base load power from wind energy. Studies have shown that up to a third of annual power production from distributed wind farms can be used to supply base load electricity with the same reliability as coal power plants. The placement of many wind plants means that grid distribution losses could be cut from 7 per cent to less than 2 per cent by adopting extensive wind energy resources. The output of most hydroelectric power plants can be coordinated with the variable output produced from wind farms. New forecasting techniques have also been developed that allow grid operators to estimate wind farm output a day ahead. Hot and cold storage techniques can be used to ensure that customers are not impacted by demand management strategies. Power storage will allow the energy produced by variable output energy sources such as wind and solar energy to be used during periods of high and low demand. It was concluded that flexibility is needed to balance supply and demand. 2 refs., 1 tab., 4 figs

  9. Residential Consumption Scheduling Based on Dynamic User Profiling

    Science.gov (United States)

    Mangiatordi, Federica; Pallotti, Emiliano; Del Vecchio, Paolo; Capodiferro, Licia

    Deployment of household appliances and of electric vehicles raises the electricity demand in the residential areas and the impact of the building's electrical power. The variations of electricity consumption across the day, may affect both the design of the electrical generation facilities and the electricity bill, mainly when a dynamic pricing is applied. This paper focuses on an energy management system able to control the day-ahead electricity demand in a residential area, taking into account both the variability of the energy production costs and the profiling of the users. The user's behavior is dynamically profiled on the basis of the tasks performed during the previous days and of the tasks foreseen for the current day. Depending on the size and on the flexibility in time of the user tasks, home inhabitants are grouped in, one over N, energy profiles, using a k-means algorithm. For a fixed energy generation cost, each energy profile is associated to a different hourly energy cost. The goal is to identify any bad user profile and to make it pay a highest bill. A bad profile example is when a user applies a lot of consumption tasks and low flexibility in task reallocation time. The proposed energy management system automatically schedules the tasks, solving a multi-objective optimization problem based on an MPSO strategy. The goals, when identifying bad users profiles, are to reduce the peak to average ratio in energy demand, and to minimize the energy costs, promoting virtuous behaviors.

  10. Mutual Information-Based Inputs Selection for Electric Load Time Series Forecasting

    Directory of Open Access Journals (Sweden)

    Nenad Floranović

    2013-02-01

    Full Text Available Providing accurate load forecast to electric utility corporations is essential in order to reduce their operational costs and increase profits. Hence, training set selection is an important preprocessing step which has to be considered in practice in order to increase the accuracy of load forecasts. The usage of mutual information (MI has been recently proposed in regression tasks, mostly for feature selection and for identifying the real instances from training sets that contains noise and outliers. This paper proposes a methodology for the training set selection in a least squares support vector machines (LS-SVMs load forecasting model. A new application of the concept of MI is presented for the selection of a training set based on MI computation between initial training set instances and testing set instances. Accordingly, several LS-SVMs models have been trained, based on the proposed methodology, for hourly prediction of electric load for one day ahead. The results obtained from a real-world data set indicate that the proposed method increases the accuracy of load forecasting as well as reduces the size of the initial training set needed for model training.

  11. Electric Vehicle (EV) Charging Management with Dynamic Distribution System Tariff

    DEFF Research Database (Denmark)

    O'Connell, Niamh; Wu, Qiuwei; Østergaard, Jacob;

    2011-01-01

    An electric vehicle (EV) charging schedule algorithm was proposed in this paper in order to charge EVs to meet EV users’ driving needs with the minimum EV charging cost and respect the local distribution system constraints. A day-ahead dynamic distribution system tariff scheme was proposed to avoid...... congestions in local distribution systems from the day-ahead planning perspective. Locational marginal pricing method was used to determine the dynamic distribution system tariff based on predicted day-ahead spot prices and predicted charging behaviors. Distribution grids of the Bornholm power system were...

  12. 基于储能水平控制的微电网能量优化调度%Energy optimal dispatch for microgrid based on state of charge control

    Institute of Scientific and Technical Information of China (English)

    牛焕娜; 罗希; 杨明皓

    2014-01-01

    With the study of renewable energy power generation for microgrid becoming more and more significant, the microgrid's safe and economic operation has been paid more and more attention to. The microgrid economic operation cannot go well without perfect energy optimization scheduling, and making full use of energy storage units, coordinate microgrid internal power supply, storage and load, and the power/energy flow between the microgrid and the large power grid. Maximizing the microgrid operation efficiency under the premise of keeping balance between the supply and demand has become an urgent problem needing solution.Aiming at the problems in current literature, the dynamic optimization and static optimization models can’t combine the day-ahead scheduling with real-time scheduling and fail to make full use of the storage and removal effect of energy storage units. In this paper, firstly, a multiple-time scale optimization scheduling scheme is put forward using the state of charge of energy storage unit as the bond between day-ahead scheduling and real-time scheduling. In day-ahead scheduling stage, a scheduling cycle is divided into 24 hours. In state of charge planning, the controllable micro power on-off plan and power generation plan are made based on the short power generation/consumption prediction data. In real-time scheduling stage, following the controllable micro power on-off planning and the state of charge of day-ahead scheduling, the future 5-15 minutes state of charge, charge and discharge power and the micro power supply power output planning is developed based on the real-time super short power generation/consumption prediction data. The day-ahead optimization model for the microgrid is also put forward, using the state of charge of energy storage units, controlled micro power supply power, and on-off state as control variables. The model puts four parts as constraint conditions within 24 hours, the controllable micro powers output, state of charge

  13. Security-Constrained Unit Commitment Based on a Realizable Energy Delivery Formulation

    Directory of Open Access Journals (Sweden)

    Hongyu Wu

    2012-01-01

    Full Text Available Security-constrained unit commitment (SCUC is an important tool for independent system operators in the day-ahead electric power market. A serious issue arises that the energy realizability of the staircase generation schedules obtained in traditional SCUC cannot be guaranteed. This paper focuses on addressing this issue, and the basic idea is to formulate the power output of thermal units as piecewise-linear function. All individual unit constraints and systemwide constraints are then reformulated. The new SCUC formulation is solved within the Lagrangian relaxation (LR framework, in which a double dynamic programming method is developed to solve individual unit subproblems. Numerical testing is performed for a 6-bus system and an IEEE 118-bus system on Microsoft Visual C# .NET platform. It is shown that the energy realizability of generation schedules obtained from the new formulation is guaranteed. Comparative case study is conducted between LR and mixed integer linear programming (MILP in solving the new formulation. Numerical results show that the near-optimal solution can be obtained efficiently by the proposed LR-based method.

  14. Peak load forecasting using Bayesian regularization, Resilient and adaptive backpropagation learning based artificial neural networks

    Energy Technology Data Exchange (ETDEWEB)

    Saini, Lalit Mohan [Department of Electrical Engineering, National Institute of Technology, Kurukshetra, Haryana 136119 (India)

    2008-07-15

    Up to 7 days ahead electrical peak load forecasting has been done using feed forward neural network based on Steepest descent, Bayesian regularization, Resilient and adaptive backpropagation learning methods, by incorporating the effect of eleven weather parameters and past peak load information. To avoid trapping of network into a state of local minima, the optimization of user-defined parameters viz., learning rate and error goal has been performed. The sliding window concept has been incorporated for selection of training data set. It was then reduced as per relevant selection according to the day type and season for which the forecast is made. To reduce the dimensionality of input matrix, the Principal Component Analysis method of factor extraction or correlation analysis technique has been used and their performance has been compared. The resultant data set was used for training of three-layered neural network. In order to increase the learning speed, the weights and biases were initialized according to Nguyen and Widrow method. To avoid over fitting, early stopping of training was done at the minimum validation error. (author)

  15. Wet tropospheric delays forecast based on Vienna Mapping Function time series analysis

    Science.gov (United States)

    Rzepecka, Zofia; Kalita, Jakub

    2016-04-01

    It is well known that the dry part of the zenith tropospheric delay (ZTD) is much easier to model than the wet part (ZTW). The aim of the research is applying stochastic modeling and prediction of ZTW using time series analysis tools. Application of time series analysis enables closer understanding of ZTW behavior as well as short-term prediction of future ZTW values. The ZTW data used for the studies were obtained from the GGOS service hold by Vienna technical University. The resolution of the data is six hours. ZTW for the years 2010 -2013 were adopted for the study. The International GNSS Service (IGS) permanent stations LAMA and GOPE, located in mid-latitudes, were admitted for the investigations. Initially the seasonal part was separated and modeled using periodic signals and frequency analysis. The prominent annual and semi-annual signals were removed using sines and consines functions. The autocorrelation of the resulting signal is significant for several days (20-30 samples). The residuals of this fitting were further analyzed and modeled with ARIMA processes. For both the stations optimal ARMA processes based on several criterions were obtained. On this basis predicted ZTW values were computed for one day ahead, leaving the white process residuals. Accuracy of the prediction can be estimated at about 3 cm.

  16. Cognitive Self-Scheduled Mechanism for Access Control in Noisy Vehicular Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Mario Manzano

    2015-01-01

    Full Text Available Within the challenging environment of intelligent transportation systems (ITS, networked control systems such as platooning guidance of autonomous vehicles require innovative mechanisms to provide real-time communications. Although several proposals are currently under discussion, the design of a rapid, efficient, flexible, and reliable medium access control mechanism which meets the specific constraints of such real-time communications applications remains unsolved in this highly dynamic environment. However, cognitive radio (CR combines the capacity to sense the radio spectrum with the flexibility to adapt to transmission parameters in order to maximize system performance and has thus become an effective approach for the design of dynamic spectrum access (DSA mechanisms. This paper presents the enhanced noncooperative cognitive division multiple access (ENCCMA proposal combining time division multiple access (TDMA and frequency division multiple access (FDMA schemes with CR techniques to obtain a mechanism fulfilling the requirements of real-time communications. The analysis presented here considers the IEEE WAVE and 802.11p as reference standards; however, the proposed medium access control (MAC mechanism can be adapted to operate on the physical layer of different standards. The mechanism also offers the advantage of avoiding signaling, thus enhancing system autonomy as well as behavior in adverse scenarios.

  17. Coordinated Volt/Var Control in Distribution Systems with Distributed Generations Based on Joint Active and Reactive Powers Dispatch

    Directory of Open Access Journals (Sweden)

    Abouzar Samimi

    2016-01-01

    Full Text Available One of the most significant control schemes in optimal operation of distribution networks is Volt/Var control (VVC. Owing to the radial structure of distribution systems and distribution lines with a small X/R ratio, the active power scheduling affects the VVC issue. A Distribution System Operator (DSO procures its active and reactive power requirements from Distributed Generations (DGs along with the wholesale electricity market. This paper proposes a new operational scheduling method based on a joint day-ahead active/reactive power market at the distribution level. To this end, based on the capability curve, a generic reactive power cost model for DGs is developed. The joint active/reactive power dispatch model presented in this paper motivates DGs to actively participate not only in the energy markets, but also in the VVC scheme through a competitive market. The proposed method which will be performed in an offline manner aims to optimally determine (i the scheduled active and reactive power values of generation units; (ii reactive power values of switched capacitor banks; and (iii tap positions of transformers for the next day. The joint active/reactive power dispatch model for daily VVC is modeled in GAMS and solved with the DICOPT solver. Finally, the plausibility of the proposed scheduling framework is examined on a typical 22-bus distribution test network over a 24-h period.

  18. 基于奖励券机制的输电阻塞管理方法%Transmission Congestion Management Method Based on Coupon Incentive Mechanism

    Institute of Scientific and Technical Information of China (English)

    贾曦; 钟海旺; 夏清; 丁茂生; 宁波

    2013-01-01

      In view of the demand on improving the efficiency of asset utilization, the effective transmission congestion management in smart grid becomes much more important. Under the market mechanism integrated with locational marginal price (LMP) and the background of two-level market with two-settlement in day-ahead and real-time market, it is proposed that the transmission congestion surplus should be used to mitigate the congestion of transmission lines; and combining with the characteristics of the shadow price of congested lines and demand side price elasticity coefficient, it is proposed to lead in the LMP-redispatch cost factors (L-R Factors) as the foundation of measuring the impact of LMP variation on redispatch cost of power grid. On this basis, a coupon mechanism, in which the day-ahead congestion surplus is taken as the source of funds to motivate more demand response (DR) on shifting loads between different periods and then alleviate the congestion in real-time markets, is put forward, and an effective approach for congestion management is formed. Case study based on extended IEEE 30-bus system show that both the proposed mechanism and method are effective.%  鉴于对提高资产利用效率的要求,有效的输电阻塞管理在智能电网中的重要性日益凸显。在节点边际电价和日前与实时“两级市场、两步结算”的市场背景下,提出应将输电阻塞盈余用于缓解线路阻塞,并结合阻塞线路影子价格和用户需求价格弹性系数的特性,引入节点边际价格-再调度费用影响因子,作为衡量节点价格变化对系统再调度成本影响的依据。在此基础上,提出了以日前阻塞盈余作为资金来源,激励用户主动响应、缓解实时网络阻塞状况的奖励券机制,形成了阻塞管理新的有效方法。扩展的IEEE 30节点算例表明了所提机制与方法的有效性。

  19. Market based solutions for increased flexibility in electricity consumption

    International Nuclear Information System (INIS)

    The main focus of this paper is on manual and automatic demand response to prices in the day ahead market. The content is mainly based on the results and experiences from the large scale Norwegian test and research project End User flexibility by efficient use of ICT (2001-2004) involving 10,894 customers with automatic meter reading (AMR) and remote load control (RLC) options. The response to hourly spot price products and intraday time of use (ToU) tariffs were tested. The registered response differs from 0.18-1 kWh/h in average per household customer for the different combination of these price signals. The largest response was achieved for the customers with both the ToU network tariff and hourly spot price. Some of the customers were offered remote controlled automatic disconnection of water heaters in the high price periods during week days. The test shows that the potential of load reduction from water heaters can be estimated to 0.6 kWh/h in the peak hours on average. For Norway this indicates that a total of 600 MWh/h automatic price elasticity could be achieved, provided that half of the 2 million Norwegian households accept RLC of their water heater referred to spot price. The benefit for load shifting is limited for each customer, but of great value for the power system as a whole. Combination of an hourly spot price contract with an intraday ToU network tariff should therefore be considered, in order to provide stable economic incentives for load reduction. One potential drawback for customers with spot price energy contracts is the risk of high electricity prices in periods of lasting scarcity. Combination with financial power contracts as an insurance for the customer is an option that will be examined in a follow up project

  20. A Genetic Algorithm Optimized Decision Tree-SVM based Stock Market Trend Prediction System

    Directory of Open Access Journals (Sweden)

    Binoy B. Nair

    2010-12-01

    Full Text Available Prediction of stock market trends has been an area of great interest both to researchers attempting to uncover the information hidden in the stock market data and for those who wish to profit by trading stocks. The extremely nonlinear nature of the stock market data makes it very difficult to design a system that can predict the future direction of the stock market with sufficient accuracy. This work presents a data mining based stock market trend prediction system, which produces highly accurate stock market forecasts. The proposed system is a genetic algorithm optimized decision tree-support vector machine (SVM hybrid, which can predict one-day-ahead trends in stockmarkets. The uniqueness of the proposed system lies in the use ofthe hybrid system which can adapt itself to the changing market conditions and in the fact that while most of the attempts at stockmarket trend prediction have approached it as a regression problem, present study converts the trend prediction task into a classification problem, thus improving the prediction accuracysignificantly. Performance of the proposed hybrid system isvalidated on the historical time series data from the Bombaystock exchange sensitive index (BSE-Sensex. The system performance is then compared to that of an artificial neural network (ANN based system and a naïve Bayes based system. It is found that the trend prediction accuracy is highest for the hybrid system and the genetic algorithm optimized decision tree- SVM hybrid system outperforms both the artificial neural network and the naïve bayes based trend prediction systems.

  1. A dynamic optimization-based architecture for polygeneration microgrids with tri-generation, renewables, storage systems and electrical vehicles

    International Nuclear Information System (INIS)

    Highlights: • We describe two national special projects on smart grid. • We developed dynamic decision model based on a MPC architecture. • We developed an optimization model for microgrids, for a specific case study. - Abstract: An overall architecture, or Energy Management System (EMS), based on a dynamic optimization model to minimize operating costs and CO2 emissions is formalized and applied to the University of Genova Savona Campus test-bed facilities consisting of a Smart Polygeneration Microgrid (SPM) and a Sustainable Energy Building (SEB) connected to such microgrid. The electric grid is a three phase low voltage distribution system, connecting many different technologies: three cogeneration micro gas turbines fed by natural gas, a photovoltaic field, three cogeneration Concentrating Solar Powered (CSP) systems (equipped with Stirling engines), an absorption chiller equipped with a storage tank, two types of electrical storage based on batteries technology (long term Na–Ni and short term Li-Ion ion), two electric vehicles charging stations, other electrical devices (inverters and smart metering systems), etc. The EMS can be used both for microgrids approximated as single bus bar (or one node) and for microgrids in which all buses are taken into account. The optimal operation of the microgrid is based on a central controller that receives forecasts and data from a SCADA system and that can schedule all dispatchable plants in the day ahead or in real time through an approach based on Model Predictive Control (MPC). The architecture is tested and applied to the case study of the Savona Campus

  2. Two-stage robust UC including a novel scenario-based uncertainty model for wind power applications

    International Nuclear Information System (INIS)

    Highlights: • Methodological framework for obtaining Robust Unit Commitment (UC) policies. • Wind-power forecast using a revisited bootstrap predictive inference approach. • Novel scenario-based model for wind-power uncertainty. • Efficient modeling framework for obtaining nearly optimal UC policies in reasonable time. • Effective incorporation of wind-power uncertainty in the UC modeling. - Abstract: The complex processes involved in the determination of the availability of power from renewable energy sources, such as wind power, impose great challenges in the forecasting processes carried out by transmission system operators (TSOs). Nowadays, many of these TSOs use operation planning tools that take into account the uncertainty of the wind-power. However, most of these methods typically require strict assumptions about the probabilistic behavior of the forecast error, and usually ignore the dynamic nature of the forecasting process. In this paper a methodological framework to obtain Robust Unit Commitment (UC) policies is presented; such methodology considers a novel scenario-based uncertainty model for wind power applications. The proposed method is composed by three main phases. The first two phases generate a sound wind-power forecast using a bootstrap predictive inference approach. The third phase corresponds to modeling and solving a one-day ahead Robust UC considering the output of the first phase. The performance of proposed approach is evaluated using as case study a new wind farm to be incorporated into the Northern Interconnected System (NIS) of Chile. A projection of wind-based power installation, as well as different characteristic of the uncertain data, are considered in this study

  3. Verification of sectoral cloud motion based direct normal irradiance nowcasting from satellite imagery

    Science.gov (United States)

    Schroedter-Homscheidt, Marion; Gesell, Gerhard

    2016-05-01

    The successful integration of solar electricity from photovoltaics or concentrating solar power plants into the existing electricity supply requires an electricity production forecast for 48 hours, while any improved surface irradiance forecast over the next upcoming hours is relevant for an optimized operation of the power plant. While numerical weather prediction has been widely assessed and is in commercial use, the short-term nowcasting is still a major field of development. European Commission's FP7 DNICast project is especially focusing on this task and this paper reports about parts of DNICast results. A nowcasting scheme based on Meteosat Second Generation cloud imagery and cloud movement tracking has been developed for Southern Spain as part of a solar production forecasting tool (CSP-FoSyS). It avoids the well-known, but not really satisfying standard cloud motion vector approach by using a sectoral approach and asking the question at which time any cloud structure will affect the power plant. It distinguishes between thin cirrus clouds and other clouds, which typically occur in different heights in the atmosphere and move in different directions. Also, their optical properties are very different - especially for the calculation of direct normal irradiances as required by concentrating solar power plants. Results for Southern Spain show a positive impact of up to 8 hours depending of the time of the day and a RMSD reduction of up to 10% in hourly DNI irradiation compared to day ahead forecasts. This paper presents the verification of this scheme at other locations in Europe and Northern Africa (BSRN and EnerMENA stations) with different cloud conditions. Especially for Jordan and Tunisia as the most relevant countries for CSP in this station list, we also find a positive impact of up to 8 hours.

  4. A new wind speed forecasting strategy based on the chaotic time series modelling technique and the Apriori algorithm

    International Nuclear Information System (INIS)

    Highlights: • Impact of meteorological factors on wind speed forecasting is taken into account. • Forecasted wind speed results are corrected by the associated rules. • Forecasting accuracy is improved by the new wind speed forecasting strategy. • Robust of the proposed model is validated by data sampled from different sites. - Abstract: Wind energy has been the fastest growing renewable energy resource in recent years. Because of the intermittent nature of wind, wind power is a fluctuating source of electrical energy. Therefore, to minimize the impact of wind power on the electrical grid, accurate and reliable wind power forecasting is mandatory. In this paper, a new wind speed forecasting approach based on based on the chaotic time series modelling technique and the Apriori algorithm has been developed. The new approach consists of four procedures: (I) Clustering by using the k-means clustering approach; (II) Employing the Apriori algorithm to discover the association rules; (III) Forecasting the wind speed according to the chaotic time series forecasting model; and (IV) Correcting the forecasted wind speed data using the associated rules discovered previously. This procedure has been verified by 31-day-ahead daily average wind speed forecasting case studies, which employed the wind speed and other meteorological data collected from four meteorological stations located in the Hexi Corridor area of China. The results of these case studies reveal that the chaotic forecasting model can efficiently improve the accuracy of the wind speed forecasting, and the Apriori algorithm can effectively discover the association rules between the wind speed and other meteorological factors. In addition, the correction results demonstrate that the association rules discovered by the Apriori algorithm have powerful capacities in handling the forecasted wind speed values correction when the forecasted values do not match the classification discovered by the association rules

  5. Flow-based market coupling. A joint ETSO-EuroPEX proposal for cross-border congestion management and integration of electricity markets in Europe. Interim report

    International Nuclear Information System (INIS)

    , it does not attempt to put forward a prescriptive 'blueprint' for a particular market model, but rather to signal a general direction. It is assumed that implementation of changes in practice would proceed through a series of regional initiatives, governed where necessary by the EU Regulation on Cross-border Exchanges of Electricity, together with the associated Guidelines. The FMC model describes arrangements for day-ahead trading. This needs to be part of a broader set of arrangements including, on one side, effective opportunities for participants to hedge price risk and, on the other side, complementary adjustment and balancing arrangements. FMC is compatible with price risk being hedged via a variety of forward physical or financial markets. The minimum set of regulatory/contractual arrangements necessary to implement FMC has been identified. Some issues concerning the status of power exchanges in some Member States remain to be resolved, particularly regarding the designated nature of the proposed day-ahead market. The transmission modelling and market co-ordination processes remain to be specified in technical detail. Both should be as transparent as reasonably possible, and the latter is likely to be an iterative process, introducing the possibility of convergence issues. Subject to the response to this interim report from other parties, ETSO and EuroPEX agree that the FMC concept should be developed further. Eventual deliverables should include inputs for consideration under the EU Comitology procedure, and advice for consideration by local implementation projects

  6. Security-Constrained Unit Commitment Based on a Realizable Energy Delivery Formulation

    OpenAIRE

    Hongyu Wu; Qiaozhu Zhai; Xiaohong Guan; Feng Gao; Hongxing Ye

    2012-01-01

    Security-constrained unit commitment (SCUC) is an important tool for independent system operators in the day-ahead electric power market. A serious issue arises that the energy realizability of the staircase generation schedules obtained in traditional SCUC cannot be guaranteed. This paper focuses on addressing this issue, and the basic idea is to formulate the power output of thermal units as piecewise-linear function. All individual unit constraints and systemwide constraints are then refor...

  7. Base

    DEFF Research Database (Denmark)

    Hjulmand, Lise-Lotte; Johansson, Christer

    2004-01-01

    BASE - Engelsk basisgrammatik er resultatet af Lise-Lotte Hjulmands grundige bearbejdning og omfattende revidering af Christer Johanssons Engelska basgrammatik. Grammatikken adskiller sig fra det svenske forlæg på en lang række punkter. Den er bl.a. tilpasset til et dansk publikum og det danske...

  8. Impact of load management on the energy management strategy of a wind-short hydro hybrid system in frequency based pricing

    International Nuclear Information System (INIS)

    Highlights: • This paper presents a new profit centric operating strategy of a hybrid power system under market environment. • The profit is ensured by optimal coordination of RES and load management approach. • The problem is formulated as dynamic optimization problem and solved using ABC algorithm. • Comparison shows that the proposed approach results more profit for the hybrid system. - Abstract: In the post restructuring era of electrical power system, each of the generating farm or utility has its own business strategy in terms of generation planning, load management and for other decisions. The basic objective of the utility is to maximize the operational profit for a given period of time. Generation scheduling for a utility with wind farm largely depends on the accuracy of wind power prediction. Therefore, it is important to explore the suitability of load management approach in coordination with the use of energy storage facility to compensate the uncertainty in wind power generation. This paper focuses mainly the operating strategy of a grid connected small hybrid power system to maximize its profit by adopting coordination between load management technique and utilization of storage plant under frequency based pricing. The optimum load scheduling has been implemented to utilities own local load. An hourly-discretized optimization algorithm is proposed and solved using artificial bee colony algorithm. To verify the effectiveness of the proposed method, the optimization problem is solved for varied wind power scenarios with different demand expectations cases in a day ahead Indian electricity market. It is noted that the proposed load management approach results more profit for the hybrid system because of better power management compared to the case when load scheduling has not been incorporated. The solution of the proposed optimization algorithm gives the strategies to be followed by the hybrid system how to operate its pump storage unit and to

  9. Effects of intraday trade on NorNed

    Energy Technology Data Exchange (ETDEWEB)

    2011-06-15

    In this report we study the effects of introducing intraday trade on the NorNed cable between Norway and the Netherlands, effectively increasing the geographical scope of the existing intraday markets in both countries, by analysing the effects on the incentives of existing and potential new market participants. The analysis of the effects on incentives is mainly based on a fundamental analysis of resource prices in the two countries, using the day-ahead supply curves in both countries. It also includes an analysis of the dynamics of trade, interdependencies between the different market time frames (day-ahead, intraday and balancing stage) and price behaviour. In addition we describe the day-ahead, intraday and balancing markets of the two countries and identify factors in the market designs which may affect the incentives for intraday trade. (Author)

  10. Uncertainty Management of Dynamic Tariff Method for Congestion Management in Distribution Networks

    DEFF Research Database (Denmark)

    Huang, Shaojun; Wu, Qiuwei; Cheng, Lin;

    2016-01-01

    is de- termined based on optimal day-ahead energy planning with forecasted parameters such as day-ahead energy prices and en- ergy needs which might be different from the parameters used by aggregators. The uncertainty management is to quantify and mitigate the risk of the congestion when employing......The dynamic tariff (DT) method is designed for the distribution system operator (DSO) to alleviate congestions that might occur in a distribution network with high penetration of distributed energy resources (DERs). Uncertainty management is required for the decentralized DT method because the DT...

  11. Forecasting and decision-making in electricity markets with focus on wind energy

    DEFF Research Database (Denmark)

    Jónsson, Tryggvi

    accounting for this effect in models for day-ahead forecasting of the prices are also presented in the thesis. Prompted by the volatile behaviour of electricity markets, considerable focus has been on time-varying and robust parameter estimates. The models derived are all based on well know methods from...... the statistical literature. The stochastic production of wind turbines prompts the need for alternative methods for optimally bidding wind power to day-ahead markets. Such bidding strategies are formulated in this thesis, which utilise the information provided by the market models. Bids that maximise expected...... revenues are found and the possibility of risk averse behaviour is discussed....

  12. An Estimation Method for Wind Power Forecast Errors Based on Numerical Feature Extraction%基于数据特征提取的风电功率预测误差估计方法

    Institute of Scientific and Technical Information of China (English)

    张凯锋; 杨国强; 陈汉一; 王颖; 丁恰

    2014-01-01

    估计风电功率预测误差对电力系统的调度与控制、安全与防御等方面具有重要意义。从风电历史数据和日前预测数据特征提取的角度,研究了日前风电功率预测误差的估计方法。首先,提取并分析影响风电功率预测误差的主要因素,包括风电出力波动程度、风电功率幅值、预测方法等,并通过数据统计分析其相关性。然后,结合风电历史运行数据,采用多元线性回归方法建立风电功率预测误差的估计模型。最后,基于比利时电力运营商 Elia 公开的风电场实际运行数据,进行了仿真算例分析。所述方法也在中国西北部某省调度系统上应用于备用需求分析,并实现了试运行。%Estimating wind power forecast errors is very important for the dispatch and control as well as security and defense of wind power systems.Based on numerical feature extraction of historical data and day-ahead forecast data,a method of estimating wind power day-ahead forecast errors is proposed.Firstly,the main factors which influence the wind power forecast errors are analyzed.These include the fluctuation and amplitude of wind power,and the forecast method used.The correlations are calculated by data statistics.Then through analyzing the historical wind power data series,the model of wind power forecast error estimation is established using the multivariate linear regression method.Finally,the performance of the proposed method is verified using the wind power data from the Belgium grid”s system operator Elia.This method has also been tested in the dispatch system of a northwest province of China.All of the results demonstrate the feasibility and practicality of this method. This work is supported by National Natural Science Foundation of China (No.5 1 1 7701 9),National High Technology Research and Development Program of China(863 Program)(No.201 1AA05A105) and State Grid Corporation of China.

  13. Impacts of Base-Case and Post-Contingency Constraint Relaxations on Static and Dynamic Operational Security

    Science.gov (United States)

    Salloum, Ahmed

    Constraint relaxation by definition means that certain security, operational, or financial constraints are allowed to be violated in the energy market model for a predetermined penalty price. System operators utilize this mechanism in an effort to impose a price-cap on shadow prices throughout the market. In addition, constraint relaxations can serve as corrective approximations that help in reducing the occurrence of infeasible or extreme solutions in the day-ahead markets. This work aims to capture the impact constraint relaxations have on system operational security. Moreover, this analysis also provides a better understanding of the correlation between DC market models and AC real-time systems and analyzes how relaxations in market models propagate to real-time systems. This information can be used not only to assess the criticality of constraint relaxations, but also as a basis for determining penalty prices more accurately. Constraint relaxations practice was replicated in this work using a test case and a real-life large-scale system, while capturing both energy market aspects and AC real-time system performance. System performance investigation included static and dynamic security analysis for base-case and post-contingency operating conditions. PJM peak hour loads were dynamically modeled in order to capture delayed voltage recovery and sustained depressed voltage profiles as a result of reactive power deficiency caused by constraint relaxations. Moreover, impacts of constraint relaxations on operational system security were investigated when risk based penalty prices are used. Transmission lines in the PJM system were categorized according to their risk index and each category was as-signed a different penalty price accordingly in order to avoid real-time overloads on high risk lines. This work also extends the investigation of constraint relaxations to post-contingency relaxations, where emergency limits are allowed to be relaxed in energy market models

  14. An application of ensemble/multi model approach for wind power production forecasting

    Science.gov (United States)

    Alessandrini, S.; Pinson, P.; Hagedorn, R.; Decimi, G.; Sperati, S.

    2011-02-01

    The wind power forecasts of the 3 days ahead period are becoming always more useful and important in reducing the problem of grid integration and energy price trading due to the increasing wind power penetration. Therefore it's clear that the accuracy of this forecast is one of the most important requirements for a successful application. The wind power forecast applied in this study is based on meteorological models that provide the 3 days ahead wind data. A Model Output Statistic correction is then performed to reduce systematic error caused, for instance, by a wrong representation of surface roughness or topography in the meteorological models. For this purpose a training of a Neural Network (NN) to link directly the forecasted meteorological data and the power data has been performed. One wind farm has been examined located in a mountain area in the south of Italy (Sicily). First we compare the performances of a prediction based on meteorological data coming from a single model with those obtained by the combination of models (RAMS, ECMWF deterministic, LAMI). It is shown that the multi models approach reduces the day-ahead normalized RMSE forecast error (normalized by nominal power) of at least 1% compared to the singles models approach. Finally we have focused on the possibility of using the ensemble model system (EPS by ECMWF) to estimate the hourly, three days ahead, power forecast accuracy. Contingency diagram between RMSE of the deterministic power forecast and the ensemble members spread of wind forecast have been produced. From this first analysis it seems that ensemble spread could be used as an indicator of the forecast's accuracy at least for the first three days ahead period.

  15. Optimal Control of Energy Storage Based on Fuzzy Correlated-chance Programming%基于模糊相关机会规划的储能优化控制

    Institute of Scientific and Technical Information of China (English)

    胡永强; 刘晨亮; 赵书强; 王明雨

    2014-01-01

    为了最大限度地使风光储联合发电系统的出力与计划出力相匹配,采用提前一日对储能装置进行优化控制的方法。因风光出力具有模糊性,提出了基于模糊相关机会规划的储能优化控制方法。该方法考虑了储能装置的出力和电量约束条件,每个时段的匹配程度用可信度表示,以一日内96个时段总的可信度均值最大为目标,采用基于模糊模拟的遗传算法求解,得到可信度均值最大时不同时段对应的储能充放电功率。算例分析表明,所提出的储能优化控制策略使风光储联合发电系统的总出力可基本跟踪计划出力曲线。%In order to maximize the match between the output of the hybrid wind/photovoltaic/energy storage system and the scheduling curve,the energy storage device is optimized and controlled one day ahead.Owing to the fuzziness of the wind and photovoltaic output,an optimal control method of energy storage is proposed based on a fuzzy correlated-chance programming theory.This method considers the constraints of the energy storage device including the power output and energy constraints, and the matching degree of each time is represented by the credibility value.So the final goal is to maximize the mean value of the total credibility within a day of 9 6 periods.By using the fuzzy simulation based genetic algorithm,the different periods of energy storage charge and discharge power corresponding to the credibility of the maximum mean value can be obtained. Numerical results analysis shows that the proposed optimal control strategy is valid for maximizing the match between the output of the hybrid wind/photovoltaic/energy storage system and the scheduling curve. This work is supported by Fundamental Research Funds for the Central Universities(No.12MS106).

  16. Optimised performance of a plug-in electric vehicle aggregator in energy and reserve markets

    International Nuclear Information System (INIS)

    Highlights: • A new model is developed to optimise the performance of a PEV aggregator in the power market. • PEVs aggregator can combine the PEVs and manage the charge/discharge of their batteries. • A new approach to calculate the satisfaction/motivation of PEV owners is proposed. • Several uncertainties are taken into account using a two-stage stochastic programing approach. • The proposed model is proficient in significantly improving the short- and long-term behaviour. - Abstract: In this paper, a new model is developed to optimise the performance of a plug-in Electric Vehicle (EV) aggregator in electricity markets, considering both short- and long-term horizons. EV aggregator as a new player of the power market can aggregate the EVs and manage the charge/discharge of their batteries. The aggregator maximises the profit and optimises EV owners’ revenue by applying changes in tariffs to compete with other market players for retaining current customers and acquiring new owners. On this basis, a new approach to calculate the satisfaction/motivation of EV owners and their market participation is proposed in this paper. Moreover, the behaviour of owners to select their supplying company is considered. The aggregator optimises the self-scheduling programme and submits the best bidding/offering strategies to the day-ahead and real-time markets. To achieve this purpose, the day-ahead and real-time energy and reserve markets are modelled as oligopoly markets, in contrast with previous works that utilised perfectly competitive ones. Furthermore, several uncertainties and constraints are taken into account using a two-stage stochastic programing approach, which have not been addressed in previous works. The numerical studies show the effectiveness of the proposed model

  17. 基于实时安全约束经济调度的自动发电控制模型%Automatic Generation Control Model Based on Real-time Security Constrained Economic Dispatch

    Institute of Scientific and Technical Information of China (English)

    石辉; 袁林山

    2015-01-01

    In order to improve intelligence level and real-time dispatch effect of automatic generation control (AGC),a secu-rity constrained economic dispatch(SCED)model for AGC active coordination based on synchronous ultra-short term predic-tion on distributed load of the whole grid was proposed depending on online data platform of new typed D5000 system.By means of rolling grey prediction on load different frequencies of the whole grid stations,anticipation of AGC adjustability was carried out for reminding artificial intervention on one hand,and on the other hand,with the target of power genera-tion of the unit close to the optimal day-ahead plan and reduction of adjustment price to the greatest extent,output of vari-ous units was pre-distributed for realizing highly intelligent AGC active coordinated dispatching function.Simulating calcula-tion was conducted on dispatching simulation system of some provincial power gird in central China area and the result indi-cated that this model was of obvious advantages in ensuring power grid security,optimizing operational index and improving automation degree of power generation dispatching.%为提高自动发电控制(automatic generation control,AGC)智能化水平及实时调节效果,依托新型 D5000系统在线数据平台,提出基于全网分布负荷同步超短期预测的 AGC 主动协调安全约束经济调度模型。通过全网站点负荷差频滚动灰色预测,一方面预判 AGC 可调以提示人工干预,另一方面以机组发电尽量接近最优日前计划及尽量降低调节代价为目标,预分配各机组出力,从而实现高度智能化的 AGC 主动协调调度功能。在华中某省级电网调度模拟系统进行仿真计算,结果表明该模型在保障电网安全、优化运行指标、提高发电调度自动化程度等方面具有明显的优势。

  18. Economic and optimal dispatching of power microgrid with renweable energy resources based on stochastic optimization%考虑随机性的微网能量优化调度模型

    Institute of Scientific and Technical Information of China (English)

    柳丹; 李强; 袁晓冬

    2014-01-01

    This paper proposes a stochastic optimization model considering the volatility of wind power and photovoltaic power in microgrid. The model optimizes the economic operation of a microgrid as well as minimizes the flow deviation at the point of common coupling (PCC) from scheduled values. First, the Latin hypercube sampling (LHS) and simultaneous backward reduction (SBR) technique are introduced to describe the stochastic nature of wind power and photovoltaic power. Then the random characteristic is introduced into the objective function of the stochastic model which is solved based on the genetic algorithm (GA). Simulation results demonstrate its rationality and effectiveness for day-ahead scheduling of a microgrid.%针对微网中风能和太阳能等可再生能源具有随机性和波动性的特点,提出了一种考虑随机性的微网能量优化调度模型,用以降低可再生能源发电预测不确定性带来的微电网和主网连接点(Point of common coupling,PCC)处的功率波动,使得微网对于主网成为一个可调度的单元,同时实现微网的经济调度。首先,采用拉丁超立方采样法(Latin hypercube sampling,LHS)和同步回带削减(Simultaneous backward reduction,SBR)技术生成可能的出力场景来描述风电和太阳能光伏发电出力的随机性。然后将PCC处能量波动引入目标函数,使得在系统期望成本最小的同时减小风电和光伏出力波动性对电网的影响,采用遗传算法求解该问题。仿真结果表明,该模型对含风电和太阳能光伏发电的微网优化调度的合理性和有效性。

  19. 基于CVaR的峰谷分时电价对供电公司购电组合策略影响分析%Influence analysis of CVaR model based TOU electricity price on portfolio strategy

    Institute of Scientific and Technical Information of China (English)

    朱文昊; 谢品杰

    2015-01-01

    基于条件风险价值(CVaR)在风险度量中的优越性,在确保满足基本收益的前提下,以供电公司购电损失的CVaR 值最小化为目标,构建了峰谷分时电价下的供电公司最优购电组合模型.进而,利用该模型对供电公司在实时市场、日前市场和中长期合约市场3个市场的供电量分配比例和有效前沿进行了算例分析,着重分析了峰谷时段不同电价差额比例对供电公司购电策略的影响.分析结果表明:相近购电组合条件下,供电公司所承担的风险随着峰谷分时电价差额比例变大而变小.供电公司可依据当地电价水平政策,适当调整不同购电市场购电量来规避经营风险.%Based on advantages of CVaR in risk measurement and on the premise of guaranteeing basic profits, taking minimum CVaR value of power supply company as a target, this paper establishes the optimal power purchasing model under TOU electricity price. In turn, using the model it analyzes different purchasing proportion in real-time electricity market, day-ahead electricity market, and mid-long term contract market and efficient frontier of E-CVaR at different price levels, and focuses on the influence of TOU on the portfolio strategy. The analysis result shows that the risk of running of power supply company decreases as electric price difference ratio increases among the similar portfolios. According to the local electric price level, power supply company may avoid risk through adjusting the purchase in different electricity markets.

  20. An online learning approach to dynamic pricing for demand response

    OpenAIRE

    Jia, Liyan; Tong, Lang; Zhao, Qing

    2014-01-01

    In this paper, the problem of optimal dynamic pricing for retail electricity with an unknown demand model is considered. Under the day-ahead dynamic pricing (a.k.a. real time pricing) mechanism, a retailer obtains electricity in a twosettlement wholesale market and serves its customers in real time. Without knowledge on the aggregated demand function of its customers, the retailer aims to maximize its retail surplus by sequentially adjusting its price based on the behavior of its customers in...

  1. A NOVEL HYBRID APPROACH TO SHORT TERM LOAD FORECASTING

    OpenAIRE

    Srivastava, Ashish Kumar; Islam, Tariqul

    2012-01-01

    The knowledge of a day ahead load is necessary for a utility in a competitive electricity market for fuel purchase scheduling, planning for energy transactions and to maintain their power reserve close to the minimum as required by Independent System Operator. Previous researches do not consider the effect of wind direction on load forecasting, however this paper investigates the effect of wind direction and weather event on load requirements and accordingly presents a novel Neuro-Fuzzy based...

  2. Effects of Risk Aversion on Market Outcomes: A Stochastic Two-Stage Equilibrium Model

    DEFF Research Database (Denmark)

    Kazempour, Jalal; Pinson, Pierre

    2016-01-01

    This paper evaluates how different risk preferences of electricity producers alter the market-clearing outcomes. Toward this goal, we propose a stochastic equilibrium model for electricity markets with two settlements, i.e., day-ahead and balancing, in which a number of conventional and stochastic...... by its optimality conditions, resulting in a mixed complementarity problem. Numerical results from a case study based on the IEEE one-area reliability test system are derived and discussed....

  3. Improving offering strategies for wind farms enhanced with storage capability

    DEFF Research Database (Denmark)

    Ding, Huajie; Hu, Zechun; Song, Yonghua;

    2015-01-01

    Due to the flexible charging and discharging capability, energy storage system (ESS) is thought of as a promising complement to wind farms (WF) in participating into electricity markets. This paper proposes a reserve-based real-time operation strategy of ESS to make arbitrage and to alleviate...... the wind power deviation from day-ahead contracts. Taking into account the operation strategy as well as two-price balancing market rules, a day-ahead bidding strategy of WF-ESS system is put forward and formulated. A modified gradient descent algorithm is described to solve the formulations. In the case...... studies, the computational efficiency of the algorithm is validated firstly. Moreover, a number of scenarios with/without considering the temporal dependence of wind power forecast error are designed and employed to compare the proposed strategy with other common ones in terms of profit....

  4. Practical operation strategies for pumped hydroelectric energy storage (PHES) utilising electricity price arbitrage

    DEFF Research Database (Denmark)

    Connolly, David; Lund, Henrik; Finn, P.;

    2011-01-01

    In this paper, three practical operation strategies (24Optimal, 24Prognostic, and 24Hsitrocial) are compared to the optimum profit feasible for a PHES facility with a 360 MW pump, 300 MW turbine, and a 2 GWh storage utilising price arbitrage on 13 electricity spot markets. The results indicate...... that almost all (not, vert, similar97%) of the profits can be obtained by a PHES facility when it is optimised using the 24Optimal strategy developed, which optimises the energy storage based on the day-ahead electricity prices. However, to maximise profits with the 24Optimal strategy, the day......-ahead electricity prices must be the actual prices which the PHES facility is charged or the PHES operator must have very accurate price predictions. Otherwise, the predicted profit could be significantly reduced and even become a loss. Finally, using the 24Optimal strategy, the PHES profit can surpass the annual...

  5. Comparison of the economic impact of different wind power forecast systems for producers

    Science.gov (United States)

    Alessandrini, S.; Davò, F.; Sperati, S.; Benini, M.; Delle Monache, L.

    2014-05-01

    Deterministic forecasts of wind production for the next 72 h at a single wind farm or at the regional level are among the main end-users requirement. However, for an optimal management of wind power production and distribution it is important to provide, together with a deterministic prediction, a probabilistic one. A deterministic forecast consists of a single value for each time in the future for the variable to be predicted, while probabilistic forecasting informs on probabilities for potential future events. This means providing information about uncertainty (i.e. a forecast of the PDF of power) in addition to the commonly provided single-valued power prediction. A significant probabilistic application is related to the trading of energy in day-ahead electricity markets. It has been shown that, when trading future wind energy production, using probabilistic wind power predictions can lead to higher benefits than those obtained by using deterministic forecasts alone. In fact, by using probabilistic forecasting it is possible to solve economic model equations trying to optimize the revenue for the producer depending, for example, on the specific penalties for forecast errors valid in that market. In this work we have applied a probabilistic wind power forecast systems based on the "analog ensemble" method for bidding wind energy during the day-ahead market in the case of a wind farm located in Italy. The actual hourly income for the plant is computed considering the actual selling energy prices and penalties proportional to the unbalancing, defined as the difference between the day-ahead offered energy and the actual production. The economic benefit of using a probabilistic approach for the day-ahead energy bidding are evaluated, resulting in an increase of 23% of the annual income for a wind farm owner in the case of knowing "a priori" the future energy prices. The uncertainty on price forecasting partly reduces the economic benefit gained by using a

  6. An application of ensemble/multi model approach for wind power production forecast.

    Science.gov (United States)

    Alessandrini, S.; Decimi, G.; Hagedorn, R.; Sperati, S.

    2010-09-01

    The wind power forecast of the 3 days ahead period are becoming always more useful and important in reducing the problem of grid integration and energy price trading due to the increasing wind power penetration. Therefore it's clear that the accuracy of this forecast is one of the most important requirements for a successful application. The wind power forecast is based on a mesoscale meteorological models that provides the 3 days ahead wind data. A Model Output Statistic correction is then performed to reduce systematic error caused, for instance, by a wrong representation of surface roughness or topography in the meteorological models. The corrected wind data are then used as input in the wind farm power curve to obtain the power forecast. These computations require historical time series of wind measured data (by an anemometer located in the wind farm or on the nacelle) and power data in order to be able to perform the statistical analysis on the past. For this purpose a Neural Network (NN) is trained on the past data and then applied in the forecast task. Considering that the anemometer measurements are not always available in a wind farm a different approach has also been adopted. A training of the NN to link directly the forecasted meteorological data and the power data has also been performed. The normalized RMSE forecast error seems to be lower in most cases by following the second approach. We have examined two wind farms, one located in Denmark on flat terrain and one located in a mountain area in the south of Italy (Sicily). In both cases we compare the performances of a prediction based on meteorological data coming from a single model with those obtained by using two or more models (RAMS, ECMWF deterministic, LAMI, HIRLAM). It is shown that the multi models approach reduces the day-ahead normalized RMSE forecast error of at least 1% compared to the singles models approach. Moreover the use of a deterministic global model, (e.g. ECMWF deterministic

  7. Linear Parameter Varying Control of Doubly Fed Induction Machines

    NARCIS (Netherlands)

    Tien, H. Nguyen; Scherer, Carsten W.; Scherpen, Jacquelien M.A.; Müller, Volkmar

    2016-01-01

    This paper is concerned with the design of a self-scheduled current controller for doubly fed induction machines. The design is based on the framework of linear parameter-varying systems where the mechanical angular speed is considered to be a measurable time-varying parameter. The objective is to o

  8. Potential Analysis of Regulating Power from Electric Vehicle (EV) Integration in Denmark

    DEFF Research Database (Denmark)

    Wu, Qiuwei; Nielsen, Arne Hejde; Østergaard, Jacob;

    2011-01-01

    The potential analysis of having electric vehicles (EVs) provide regulating power has been implemented. The possible regulating power capacity from EVs and the economic return for EV users by providing regulating power are obtained. A spot price based charging schedule scenario has been used to do...... the day-ahead charging schedule for all EVs based on the predicted driving pattern. On top of the obtained charging schedule, the predicted EV availability and the charging schedule are used to calculate the possible regulating power capacity from EVs for both up regulating power and down regulating power...

  9. Electricity Portfolio Management: Optimal Peak / Off-Peak Allocations

    OpenAIRE

    Huisman, Ronald; Mahieu, Ronald; Schlichter, Felix

    2007-01-01

    textabstractElectricity purchasers manage a portfolio of contracts in order to purchase the expected future electricity consumption profile of a company or a pool of clients. This paper proposes a mean-variance framework to address the concept of structuring the portfolio and focuses on how to allocate optimal positions in peak and off-peak forward contracts. It is shown that the optimal allocations are based on the difference in risk premiums per unit of day-ahead risk as a measure of relati...

  10. Into the new electricity age with Optimal integration of decentralized energy resources - The FENIX Project

    Energy Technology Data Exchange (ETDEWEB)

    Cech, Heinz; Fuchs, Erich; Heher, Anton; Ilo, Albana; Sezi, Tevfik; Trimmel, Johann; Werner, Thomas; Marti-Rodriguez, Juan

    2010-09-15

    Decentralized Energy Resources (DERs) will play a significant role in future energy scenarios. Today, the 'plug and forget' connection principle for renewable energy resources has the goal to maximize the active power transfer, without using their real capabilities. Other DERs based on fossil fuels are only activated in emergency situations. This paper describes the results of a demonstration project, where DERs installed in a large distribution area are utilized for participating in the day ahead energy market, frequency and voltage support for the transmission system, voltage support at specific distribution locations and feeders, and stability support in emergency situations.

  11. Exponential smoothing approaches for prediction in real-time electricity markets

    DEFF Research Database (Denmark)

    Jónsson, Tryggvi; Pinson, Pierre; Nielsen, Henrik Aalborg;

    2014-01-01

    The optimal design of offering strategies for wind power producers is commonly based on unconditional (and, hence, constant) expectation values for prices in real-time markets, directly defining their loss function in a stochastic optimization framework. This is why it may certainly be advantageous...... on the well-known Holt–Winters model with a daily seasonal cycle, either in its conventional form or conditioned upon exogenous variables, such as: (i) day-ahead price; (ii) system load; and (iii) wind power penetration. The superiority of the proposed approach over a number of common benchmarks...

  12. Belpex and trilateral market coupling

    International Nuclear Information System (INIS)

    interconnections, Aspects of current explicit day-ahead allocation, Daily Market Process, Road-map by Regulators, CRE-CREG-DTE Road-map: Extension to NorNed and other areas, Further steps, Transmission Rights, Flow-based transmission model, Towards an Open and Multilateral Market Coupling). (J.S.)

  13. Multi-Agent System-Based Microgrid Operation Strategy for Demand Response

    Directory of Open Access Journals (Sweden)

    Hee-Jun Cha

    2015-12-01

    Full Text Available The microgrid and demand response (DR are important technologies for future power grids. Among the variety of microgrid operations, the multi-agent system (MAS has attracted considerable attention. In a microgrid with MAS, the agents installed on the microgrid components operate optimally by communicating with each other. This paper proposes an operation algorithm for the individual agents of a test microgrid that consists of a battery energy storage system (BESS and an intelligent load. A microgrid central controller to manage the microgrid can exchange information with each agent. The BESS agent performs scheduling for maximum benefit in response to the electricity price and BESS state of charge (SOC through a fuzzy system. The intelligent load agent assumes that the industrial load performs scheduling for maximum benefit by calculating the hourly production cost. The agent operation algorithm includes a scheduling algorithm using day-ahead pricing in the DR program and a real-time operation algorithm for emergency situations using emergency demand response (EDR. The proposed algorithm and operation strategy were implemented both by a hardware-in-the-loop simulation test using OPAL-RT and an actual hardware test by connecting a new distribution simulator.

  14. Electricity market models and RES integration: The Greek case

    International Nuclear Information System (INIS)

    This paper presents an extensive analysis of the Greek electricity market for the next 7-year period (2014–2020) based on an hour-by-hour simulation considering five different RES technologies, namely wind, PV, small hydro, biomass and CHP with emphasis on PV integration. The impact of RES penetration on the electricity market operation is evaluated under two different models regarding the organization of the Greek wholesale day-ahead electricity market: a mandatory power pool for year 2014 (current market design) and a power exchange for the period 2015–2020 (Target Model). An integrated software tool is used for the simulation of the current and the future day-ahead market clearing algorithm of the Greek wholesale electricity market. Simulation results indicate the impact of the anticipated large-scale RES integration, in conjunction with each market model, on specific indicators of the Greek electricity market in the long-term. - Highlights: • Analysis of the Greek electricity market for the next 7-year period (2014–2020) based on hour-by-hour simulation. • Five different RES technologies are considered with emphasis on PV integration. • A power pool (for 2014) and a power exchange (for 2015–2020) are considered. • Various market indicators are used for the analysis of the impact of the RES integration on the Greek electricity market. • Two alternative tariff schemes for the compensation of the new ground-mounted PV units from 2015 onwards are investigated

  15. Linear Parameter-Varying Feedforward Control: A Missile Autopilot Design

    OpenAIRE

    Theis, Julian; Pfifer, Harald; Knoblach, Andreas; Saupe, Florian; Werner, Herbert

    2015-01-01

    The feedforward path of an autopilot is designed for the longitudinal dynamics of a tactical missile. A linear parameter-varying model is used to synthesize a self-scheduled control law based on a parameter-dependent Lyapunov function. The controller is evaluated on a nonlinear model of industrial complexity both under nominal conditions and parametric uncertainty. Tracking performance is significantly enhanced while leaving robustness properties of an existing feedback controller unaltered.

  16. Touch BASE

    CERN Multimedia

    Antonella Del Rosso

    2015-01-01

    In a recent Nature article (see here), the BASE collaboration reported the most precise comparison of the charge-to-mass ratio of the proton to its antimatter equivalent, the antiproton. This result is just the beginning and many more challenges lie ahead.   CERN's AD Hall, where the BASE experiment is set-up. The Baryon Antibaryon Symmetry Experiment (BASE) was approved in June 2013 and was ready to take data in August 2014. During these 14 months, the BASE collaboration worked hard to set up its four cryogenic Penning traps, which are the heart of the whole experiment. As their name indicates, these magnetic devices are used to trap antiparticles – antiprotons coming from the Antiproton Decelerator – and particles of matter – negative hydrogen ions produced in the system by interaction with a degrader that slows the antiprotons down, allowing scientists to perform their measurements. “We had very little time to set up the wh...

  17. How to improve an un-alterable model forecast? A sequential data assimilation based error updating approach

    Science.gov (United States)

    Gragne, A. S.; Sharma, A.; Mehrotra, R.; Alfredsen, K. T.

    2012-12-01

    Accuracy of reservoir inflow forecasts is instrumental for maximizing value of water resources and influences operation of hydropower reservoirs significantly. Improving hourly reservoir inflow forecasts over a 24 hours lead-time is considered with the day-ahead (Elspot) market of the Nordic exchange market in perspectives. The procedure presented comprises of an error model added on top of an un-alterable constant parameter conceptual model, and a sequential data assimilation routine. The structure of the error model was investigated using freely available software for detecting mathematical relationships in a given dataset (EUREQA) and adopted to contain minimum complexity for computational reasons. As new streamflow data become available the extra information manifested in the discrepancies between measurements and conceptual model outputs are extracted and assimilated into the forecasting system recursively using Sequential Monte Carlo technique. Besides improving forecast skills significantly, the probabilistic inflow forecasts provided by the present approach entrains suitable information for reducing uncertainty in decision making processes related to hydropower systems operation. The potential of the current procedure for improving accuracy of inflow forecasts at lead-times unto 24 hours and its reliability in different seasons of the year will be illustrated and discussed thoroughly.

  18. Web based foundry knowledge base

    Directory of Open Access Journals (Sweden)

    A. Stawowy

    2009-01-01

    Full Text Available The main assumptions and functions of proposed Foundry Knowledge Base (FKB are presented in this paper. FKB is a framework forinformation exchange of casting products and manufacturing methods. We use CMS (Content Management System to develope andmaintain our web-based system. The CastML – XML dialect developed by authors for description of casting products and processes – isused as a tool for information interchange between ours and outside systems, while SQL is used to store and edit knowledge rules and alsoto solve the basic selection problems in the rule-based module. Besides the standard functions (companies data, news, events, forums and media kit, our website contains a number of nonstandard functions; the intelligent search module based on expert system is the main advantage of our solution. FKB is to be a social portal which content will be developed by foundry community.

  19. Electricity market clearing with improved dispatch of stochastic production

    DEFF Research Database (Denmark)

    Morales González, Juan Miguel; Zugno, Marco; Pineda, Salvador;

    2014-01-01

    In this paper, we consider an electricity market that consists of a day-ahead and a balancing settlement, and includes a number of stochastic producers. We first introduce two reference procedures for scheduling and pricing energy in the day-ahead market: on the one hand, a conventional network-c...

  20. Optimal offering and operating strategies for wind-storage systems with linear decision rules

    DEFF Research Database (Denmark)

    Ding, Huajie; Pinson, Pierre; Hu, Zechun;

    2016-01-01

    The participation of wind farm-energy storage systems (WF-ESS) in electricity markets calls for an integrated view of day-ahead offering strategies and real-time operation policies. Such an integrated strategy is proposed here by co-optimizing offering at the day-ahead stage and operation policy...

  1. Standardized Software for Wind Load Forecast Error Analyses and Predictions Based on Wavelet-ARIMA Models - Applications at Multiple Geographically Distributed Wind Farms

    Energy Technology Data Exchange (ETDEWEB)

    Hou, Zhangshuan; Makarov, Yuri V.; Samaan, Nader A.; Etingov, Pavel V.

    2013-03-19

    Given the multi-scale variability and uncertainty of wind generation and forecast errors, it is a natural choice to use time-frequency representation (TFR) as a view of the corresponding time series represented over both time and frequency. Here we use wavelet transform (WT) to expand the signal in terms of wavelet functions which are localized in both time and frequency. Each WT component is more stationary and has consistent auto-correlation pattern. We combined wavelet analyses with time series forecast approaches such as ARIMA, and tested the approach at three different wind farms located far away from each other. The prediction capability is satisfactory -- the day-ahead prediction of errors match the original error values very well, including the patterns. The observations are well located within the predictive intervals. Integrating our wavelet-ARIMA (‘stochastic’) model with the weather forecast model (‘deterministic’) will improve our ability significantly to predict wind power generation and reduce predictive uncertainty.

  2. Foundation: Transforming data bases into knowledge bases

    Science.gov (United States)

    Purves, R. B.; Carnes, James R.; Cutts, Dannie E.

    1987-01-01

    One approach to transforming information stored in relational data bases into knowledge based representations and back again is described. This system, called Foundation, allows knowledge bases to take advantage of vast amounts of pre-existing data. A benefit of this approach is inspection, and even population, of data bases through an intelligent knowledge-based front-end.

  3. Elspot: Nord Pool Spot Integration in MASCEM Electricity Market Simulator

    DEFF Research Database (Denmark)

    Fernandes, Ricardo; Santos, Gabriel; Praca, Isabel;

    2014-01-01

    models and player types as possible. This paper presents a new negotiation model implemented in MASCEM based on the negotiation model used in day-ahead market (Elspot) of Nord Pool. This is a key module to study competitive electricity markets, as it presents well defined and distinct characteristics...... in market players' interactions and generated emerging problems and new issues to be addressed. In order to provide players with competitive advantage in the market, decision support tools that facilitate the study and understanding of these markets become extremely useful. In this context arises MASCEM...... (Multi-Agent Simulator of Competitive Electricity Markets), a multi-agent based simulator that models real electricity markets. To reinforce MASCEM with the capability of recreating the elect ricity markets reality in the fullest possible extent, it is crucial to make it able to simulate as many market...

  4. Automated Price and Demand Response Demonstration for Large Customers in New York City using OpenADR

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Joyce Jihyun; Yin, Rongxin; Kiliccote, Sila

    2013-10-01

    Open Automated Demand Response (OpenADR), an XML-based information exchange model, is used to facilitate continuous price-responsive operation and demand response participation for large commercial buildings in New York who are subject to the default day-ahead hourly pricing. We summarize the existing demand response programs in New York and discuss OpenADR communication, prioritization of demand response signals, and control methods. Building energy simulation models are developed and field tests are conducted to evaluate continuous energy management and demand response capabilities of two commercial buildings in New York City. Preliminary results reveal that providing machine-readable prices to commercial buildings can facilitate both demand response participation and continuous energy cost savings. Hence, efforts should be made to develop more sophisticated algorithms for building control systems to minimize customer's utility bill based on price and reliability information from the electricity grid.

  5. INVOLUTIVE BASES UNDER COMPOSITION

    Institute of Scientific and Technical Information of China (English)

    Zailiang TANG

    2007-01-01

    In this paper, the behaviors of involutive bases under composition operation are studied.For two kinds of involutive bases, i.e., Pommaret bases, Janet bases, we study their behavior problems under composition. Some further problems are also proposed.

  6. Belpex and trilateral market coupling

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-01-15

    on the interconnections, Aspects of current explicit day-ahead allocation, Daily Market Process, Road-map by Regulators, CRE-CREG-DTE Road-map: Extension to NorNed and other areas, Further steps, Transmission Rights, Flow-based transmission model, Towards an Open and Multilateral Market Coupling). (J.S.)

  7. Data on Support Vector Machines (SVM) model to forecast photovoltaic power.

    Science.gov (United States)

    Malvoni, M; De Giorgi, M G; Congedo, P M

    2016-12-01

    The data concern the photovoltaic (PV) power, forecasted by a hybrid model that considers weather variations and applies a technique to reduce the input data size, as presented in the paper entitled "Photovoltaic forecast based on hybrid pca-lssvm using dimensionality reducted data" (M. Malvoni, M.G. De Giorgi, P.M. Congedo, 2015) [1]. The quadratic Renyi entropy criteria together with the principal component analysis (PCA) are applied to the Least Squares Support Vector Machines (LS-SVM) to predict the PV power in the day-ahead time frame. The data here shared represent the proposed approach results. Hourly PV power predictions for 1,3,6,12, 24 ahead hours and for different data reduction sizes are provided in Supplementary material.

  8. Determination of the Prosumer's Optimal Bids

    Science.gov (United States)

    Ferruzzi, Gabriella; Rossi, Federico; Russo, Angela

    2015-12-01

    This paper considers a microgrid connected with a medium-voltage (MV) distribution network. It is assumed that the microgrid, which is managed by a prosumer, operates in a competitive environment and participates in the day-ahead market. Then, as the first step of the short-term management problem, the prosumer must determine the bids to be submitted to the market. The offer strategy is based on the application of an optimization model, which is solved for different hourly price profiles of energy exchanged with the main grid. The proposed procedure is applied to a microgrid and four different its configurations were analyzed. The configurations consider the presence of thermoelectric units that only produce electricity, a boiler or/and cogeneration power plants for the thermal loads, and an electric storage system. The numerical results confirmed the numerous theoretical considerations that have been made.

  9. A stochastic framework for clearing of reactive power market

    Energy Technology Data Exchange (ETDEWEB)

    Amjady, N. [Department of Electrical Engineering, Semnan University, Semnan (Iran); Rabiee, A.; Shayanfar, H.A. [Center of excellence for Power System Automation and Operation, Department of Electrical Engineering, Iran University of Science and Technology, Tehran (Iran)

    2010-01-15

    This paper presents a new stochastic framework for clearing of day-ahead reactive power market. The uncertainty of generating units in the form of system contingencies are considered in the reactive power market-clearing procedure by the stochastic model in two steps. The Monte-Carlo Simulation (MCS) is first used to generate random scenarios. Then, in the second step, the stochastic market-clearing procedure is implemented as a series of deterministic optimization problems (scenarios) including non-contingent scenario and different post-contingency states. In each of these deterministic optimization problems, the objective function is total payment function (TPF) of generators which refers to the payment paid to the generators for their reactive power compensation. The effectiveness of the proposed model is examined based on the IEEE 24-bus Reliability Test System (IEEE 24-bus RTS). (author)

  10. Multiobjective clearing of reactive power market in deregulated power systems

    Energy Technology Data Exchange (ETDEWEB)

    Rabiee, A.; Shayanfar, H. [Center of Excellence for Power System Automation and Operation, Electrical Engineering Department, Iran University of Science and Technology (IUST), Narmak, Tehran 16846 (Iran); Amjady, N. [Department of Electrical Engineering, Semnan University, Semnan (Iran)

    2009-09-15

    This paper presents a day-ahead reactive power market which is cleared in the form of multiobjective context. Total payment function (TPF) of generators, representing the payment paid to the generators for their reactive power compensation, is considered as the main objective function of reactive power market. Besides that, voltage security margin, overload index, and also voltage drop index are the other objective functions of the optimal power flow (OPF) problem to clear the reactive power market. A Multiobjective Mathematical Programming (MMP) formulation is implemented to solve the problem of reactive power market clearing using a fuzzy approach to choose the best compromise solution according to the specific preference among various non-dominated (pareto optimal) solutions. The effectiveness of the proposed method is examined based on the IEEE 24-bus reliability test system (IEEE 24-bus RTS). (author)

  11. FY94 and FY95 thermal stabilization campaign report

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, W.S.

    1996-01-10

    The report provides a synopsis of the FY94/95 Thermal Stabilization Campaign. The FY94 Thermal Stabilization Campaign ran from November 1, 1994 to June 13, 1995 and stabilized 236 items (22 kg) of reactive plutonium bearing material. A total of 49 cans of stabilized material was moved to the vaults for interim storage. While the initial downtime was high, with an Operating Efficiency (OE) of 27% over the first 3 months, the OE improved to 78% during the last 5 months for an overall DE of 58%. The campaign was completed 85 days ahead of schedule thus exceeding the ``Excellent``date for the Performance Base Incentive (PBI) for this campaign by 25 business days.

  12. Trading Strategies for Distribution Company with Stochastic Distributed Energy Resources

    DEFF Research Database (Denmark)

    Zhang, Chunyu; Wang, Qi; Wang, Jianhui;

    2016-01-01

    This paper proposes a methodology to address the trading strategies of a proactive distribution company (PDISCO) engaged in the transmission-level (TL) markets. A one-leader multi-follower bilevel model is presented to formulate the gaming framework between the PDISCO and markets. The lower......-level (LL) problems include the TL day-ahead market and scenario-based real-time markets, respectively with the objectives of maximizing social welfare and minimizing operation cost. The upper-level (UL) problem is to maximize the PDISCO's prot across these markets. The PDISCO's strategic oers....../bids interactively in uence the outcomes of each market. Since the LL problems are linear and convex, while the UL problem is non-linear and non-convex, an equivalent primal-dual approach is used to reformulate this bilevel model to a solvable mathematical program with equilibrium constraints (MPEC...

  13. Forecasting Electricity Spot Prices Accounting for Wind Power Predictions

    DEFF Research Database (Denmark)

    Jónsson, Tryggvi; Pinson, Pierre; Nielsen, Henrik Aalborg;

    2013-01-01

    A two-step methodology for forecasting of electricity spot prices is introduced, with focus on the impact of predicted system load and wind power generation. The nonlinear and nonstationary influence of these explanatory variables is accommodated in a first step based on a nonparametric and time......-varying regression model. In a second step, time-series models, i.e., ARMA and Holt–Winters, are applied to account for residual autocorrelation and seasonal dynamics. Empirical results are presented for out-of-sample forecasts of day-ahead prices in the Western Danish price area of Nord Pool's Elspot, during a two...... year period covering 2010–2011. These results clearly demonstrate the practical benefits of accounting for the complex influence of these explanatory variables....

  14. A Generation Pricing Method with Capacity Bidding

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Due to historic reasons China encounters some special difficulties in ESI (electricity system industry) restructuring. An easy and simple electricity value equivalent (es-EVE) method for day-ahead pool purchase pricing of China is therefore presented in this paper. The es-EVE method is different from two-part and one-part tariffs. It is more like the UK's method in form, but revised for China with some new concepts and procedure. The main contributions of it include: (1) Find two kinds of eigenvalue, namely EVEs, in an optimization model, (2) Define new concepts of virtual units and feasible region, (3) Twice merit orderings are employed successively to find marginal price. They are simple maximum and minimum comparison procedures and so on. The special economic significance of the method for China is discussed, and some suggestion for ESI restructuring based on es-EVE method are provided. A case study is offered at the end of the paper.

  15. Spot Markets Indices as Benchmarks of Formation of Future Price Trends in the Power Exchanges of Eastern Europe

    Directory of Open Access Journals (Sweden)

    Polikevych Nataliya I.

    2016-01-01

    Full Text Available The article is concerned with a theoretical generalization of the use of indices for electric power at the European spot exchanges and elaborating proposals on establishment of a similar spot index for the Ukrainian power exchange. 16 indices that are published daily by the power exchanges BSP Regional Energy Exchange, Power Exchange Central Europe, Polish Power Exchange and Opcom have been analyzed. It has been indicated that these indices are used for electricity price forecasting and monitoring the situation in the power market. The article examines the way spot indices are calculated by power exchanges, based on the value of the arithmetic average of market prices «day ahead». Imperfection of such way of calculation for price index values has been substantiated. The key characteristics of the future price index for Ukrainian spot market as benchmarks within the introduction of futures contracts for electricity have been identified.

  16. Maximizing the Social Welfare of Virtual Power Players Operation in Case of Excessive Wind Power

    DEFF Research Database (Denmark)

    Faria, Pedro; Vale, Zita; Morais, Hugo

    2013-01-01

    based generation (including wind power) has caused several changes in the operation and planning of power systems and of electricity markets. Sometimes the available non-dispatchable generation is higher than the demand. This generation must be used; otherwise it is wasted if not stored or used...... to supply additional demand. New policies and market rules, as well as new players, are needed in order to competitively integrate all the resources. The methodology proposed in this paper aims at the maximization of the social welfare in a distribution network operated by a virtual power player...... and day-ahead resources forecast differ significantly. The distribution network characteristics and concerns are addressed by including the network constraints in the optimization model. The proposed methodology has been implemented in GAMS optimization tool and its application is illustrated...

  17. Cross-Correlation Earthquake Precursors in the Hydrogeochemical and Geoacoustic Signals for the Kamchatka Peninsula

    CERN Document Server

    Ryabinin, G V; Polyakov, Yu S; Timashev, S F

    2012-01-01

    We propose a new type of earthquake precursor based on the analysis of correlation dynamics between geophysical signals of different nature. The precursor is found using a two-parameter cross-correlation function introduced within the framework of flicker-noise spectroscopy, a general statistical physics approach to the analysis of time series. We consider an example of cross-correlation analysis for water salinity time series, an integral characteristic of the chemical composition of groundwater, and geoacoustic emissions recorded at the G-1 borehole on the Kamchatka peninsula in the time frame from 2001 to 2003, which is characterized by a sequence of three groups of significant seismic events. We found that cross-correlation precursors took place 27, 31, and 35 days ahead of the strongest earthquakes for each group of seismic events, respectively. At the same time, precursory anomalies in the signals themselves were observed only in the geoacoustic emissions for one group of earthquakes.

  18. Convergence of electricity wholesale prices in Europe - a Kalman filter approach

    International Nuclear Information System (INIS)

    This study tests the hypothesis that the ongoing restructuring process in the European electricity sector, as well as market participants' adaptation to the new legal framework, have caused electricity wholesale day-ahead prices to converge towards arbitrage freeness. Using hourly cross-border capacity auction results at the Dutch-German and at the Danish-German border for the years 2002 to 2004, and the respective spot prices, we estimate a time-varying coefficient model based on the law of one price (LOP). The results of these estimations are used to calculate the speed of convergence towards the LOP. While the German - Dutch prices and the German - West Danish prices are clearly developing towards arbitrage freeness, the German and East Danish prices do not exhibit significant convergence. (Author)

  19. Computer-assisted cognitive-behavior therapy for depression.

    Science.gov (United States)

    Eells, Tracy D; Barrett, Marna S; Wright, Jesse H; Thase, Michael

    2014-06-01

    This article reviews the use of computer technology in treating depression as a substitute or adjunct for standard therapy. It discusses advantages and disadvantages of introducing computer technology as a treatment option, problems and barriers to expanded use, the varieties of computer-assisted psychotherapy for major depression, and relevant research. Three specific Internet-based programs are described, assessed and compared: Good Days Ahead, Beating the Blues, and MoodGYM. The authors conclude that these and similar programs are promising. Preliminary outcome studies suggest that these programs produce outcome similar to standard therapy, although methodological shortcomings limit confidence in these findings. Suggestions are offered for practitioners considering the addition of computer assistance to their treatment of depression. PMID:24059735

  20. The Optimized Operation of Gas Turbine Combined Heat and Power Units Oriented for the Grid-Connected Control

    Science.gov (United States)

    Xia, Shu; Ge, Xiaolin

    2016-04-01

    In this study, according to various grid-connected demands, the optimization scheduling models of Combined Heat and Power (CHP) units are established with three scheduling modes, which are tracking the total generation scheduling mode, tracking steady output scheduling mode and tracking peaking curve scheduling mode. In order to reduce the solution difficulty, based on the principles of modern algebraic integers, linearizing techniques are developed to handle complex nonlinear constrains of the variable conditions, and the optimized operation problem of CHP units is converted into a mixed-integer linear programming problem. Finally, with specific examples, the 96 points day ahead, heat and power supply plans of the systems are optimized. The results show that, the proposed models and methods can develop appropriate coordination heat and power optimization programs according to different grid-connected control.

  1. A stochastic framework for clearing of reactive power market

    International Nuclear Information System (INIS)

    This paper presents a new stochastic framework for clearing of day-ahead reactive power market. The uncertainty of generating units in the form of system contingencies are considered in the reactive power market-clearing procedure by the stochastic model in two steps. The Monte-Carlo Simulation (MCS) is first used to generate random scenarios. Then, in the second step, the stochastic market-clearing procedure is implemented as a series of deterministic optimization problems (scenarios) including non-contingent scenario and different post-contingency states. In each of these deterministic optimization problems, the objective function is total payment function (TPF) of generators which refers to the payment paid to the generators for their reactive power compensation. The effectiveness of the proposed model is examined based on the IEEE 24-bus Reliability Test System (IEEE 24-bus RTS). (author)

  2. Multiobjective clearing of reactive power market in deregulated power systems

    International Nuclear Information System (INIS)

    This paper presents a day-ahead reactive power market which is cleared in the form of multiobjective context. Total payment function (TPF) of generators, representing the payment paid to the generators for their reactive power compensation, is considered as the main objective function of reactive power market. Besides that, voltage security margin, overload index, and also voltage drop index are the other objective functions of the optimal power flow (OPF) problem to clear the reactive power market. A Multiobjective Mathematical Programming (MMP) formulation is implemented to solve the problem of reactive power market clearing using a fuzzy approach to choose the best compromise solution according to the specific preference among various non-dominated (pareto optimal) solutions. The effectiveness of the proposed method is examined based on the IEEE 24-bus reliability test system (IEEE 24-bus RTS). (author)

  3. Audit of the process of determination of available cross-border electricity transmission capacity in the Netherlands

    International Nuclear Information System (INIS)

    The objective of this audit has been to analyse and to evaluate the process of determination of available cross-border electricity transmission capacity in the Netherlands as applied by the Dutch transmission system operator TenneT. In particular, the scope has been to give a survey of the corresponding responsibilities of TenneT as defined primarily by the Dutch Grid Code, to analyse the way TenneT fulfils these responsibilities, and to analyse and evaluate the decisions taken and the methods applied by TenneT for each step of this process. In addition, recommendations regarding possibilities of netting imports and exports in day-ahead capacity allocation have been requested. We have based this audit on comprehensive meetings with TenneT, on publicly available documents mainly from DTe and TenneT, and on non-public documents made available to us by TenneT. 26 refs

  4. Data on Support Vector Machines (SVM) model to forecast photovoltaic power.

    Science.gov (United States)

    Malvoni, M; De Giorgi, M G; Congedo, P M

    2016-12-01

    The data concern the photovoltaic (PV) power, forecasted by a hybrid model that considers weather variations and applies a technique to reduce the input data size, as presented in the paper entitled "Photovoltaic forecast based on hybrid pca-lssvm using dimensionality reducted data" (M. Malvoni, M.G. De Giorgi, P.M. Congedo, 2015) [1]. The quadratic Renyi entropy criteria together with the principal component analysis (PCA) are applied to the Least Squares Support Vector Machines (LS-SVM) to predict the PV power in the day-ahead time frame. The data here shared represent the proposed approach results. Hourly PV power predictions for 1,3,6,12, 24 ahead hours and for different data reduction sizes are provided in Supplementary material. PMID:27622206

  5. Operational Strategies for a Portfolio of Wind Farms and CHP Plants in a Two-Price Balancing Market

    DEFF Research Database (Denmark)

    Hellmers, Anna; Zugno, Marco; Skajaa, Anders;

    2015-01-01

    . We investigate two different operational strategies, which differ in whether the CHP plant and the wind farm are operated jointly or independently, and we evaluate their economic performance on a real case study based on a CHP-wind system located in the western part of Denmark. We present......In this paper we explore the portfolio effect of a system consisting of a Combined Heat and Power (CHP) plant and a wind farm. The goal is to increase the overall profit of the portfolio by reducing imbalances, and consequently their implicit penalty in a two-price balancing market for electricity...... a comprehensive mathematical model for describing the different heat and power production units of the CHP plant, and suggest different ways of determining its operation in a setup with two trading floors: a day-ahead market and a balancing market. We build a simulation framework that runs in a rolling...

  6. Modeling and analysis of a decentralized electricity market: An integrated simulation/optimization approach

    International Nuclear Information System (INIS)

    In this study, a model is developed to investigate the implications of an hourly day-ahead competitive power market on generator profits, electricity prices, availability and supply security. An integrated simulation/optimization approach is employed integrating a multi-agent simulation model with two alternative optimization models. The simulation model represents interactions between power generator, system operator, power user and power transmitter agents while the network flow optimization model oversees and optimizes the electricity flows, dispatches generators based on two alternative approaches used in the modeling of the underlying transmission network: a linear minimum cost network flow model and a non-linear alternating current optimal power flow model. Supply, demand, transmission, capacity and other technological constraints are thereby enforced. The transmission network, on which the scenario analyses are carried out, includes 30 bus, 41 lines, 9 generators, and 21 power users. The scenarios examined in the analysis cover various settings of transmission line capacities/fees, and hourly learning algorithms. Results provide insight into key behavioral and structural aspects of a decentralized electricity market under network constraints and reveal the importance of using an AC network instead of a simplified linear network flow approach. -- Highlights: ► An agent-based simulation model with an AC transmission environment with a day-ahead market. ► Physical network parameters have dramatic effects over price levels and stability. ► Due to AC nature of transmission network, adaptive agents have more local market power than minimal cost network flow. ► Behavior of the generators has significant effect over market price formation, as pointed out by bidding strategies. ► Transmission line capacity and fee policies are found to be very effective in price formation in the market.

  7. Multi-market energy procurement for a large consumer using a risk-aversion procedure

    Energy Technology Data Exchange (ETDEWEB)

    Zare, Kazem [Tarbiat Modares University, Tehran, P.O. Box 14115-111 (Iran); Conejo, Antonio J. [Castilla-La Mancha University, Ciudad Real (Spain); Carrion, Miguel [Castilla-La Mancha University, Toledo (Spain); Moghaddam, Mohsen Parsa [Tarbiat Modares University, Tehran (Iran)

    2010-01-15

    This paper provides a technique to derive the bidding strategy in the day-ahead market of a large consumer that procures its electricity demand in both the day-ahead market and a subsequent adjustment market. Price uncertainty is modeled using concepts derived from information gap decision theory, which allows deriving robust decisions with respect to price volatility. Risk aversion is built implicitly within the proposed model. Correlations among prices in the day-ahead and the adjustment markets are properly modeled. The proposed technique is illustrated through a realistic case study. (author)

  8. Indicators of gas gross markets - November 2009-December 2012

    International Nuclear Information System (INIS)

    For each month from November 2009 until December 2012, this document proposes a set of graphs which illustrate the evolution of gas price (day-ahead price in France, difference between the North gas exchange point and South exchange point, price volatility, difference between M + 1 PEG price and day-ahead price, day-ahead price in Belgium, Germany and Netherlands, relationship between import price and market price), the development of gas trade in France (transactions, volumes, supplied volume in European countries) and indicators related to infrastructures (availability in gas entry points, use of infrastructure with respect to price difference on markets)

  9. A dynamic knowledge base based search engine

    Institute of Scientific and Technical Information of China (English)

    WANG Hui-jin; HU Hua; LI Qing

    2005-01-01

    Search engines have greatly helped us to find thedesired information from the Intemet. Most search engines use keywords matching technique. This paper discusses a Dynamic Knowledge Base based Search Engine (DKBSE), which can expand the user's query using the keywords' concept or meaning. To do this, the DKBSE needs to construct and maintain the knowledge base dynamically via the system's searching results and the user's feedback information. The DKBSE expands the user's initial query using the knowledge base, and returns the searched information after the expanded query.

  10. Knowledge Based Strategies for Knowledge Based Organizations

    Directory of Open Access Journals (Sweden)

    Madalina Cristina Tocan

    2012-12-01

    Full Text Available In the present, we can observe that a new economy is arising. It is an economy based on knowledge and ideas, in which the key factor for prosperity and for creation of the new jobs is the knowledge capitalization. Knowledge capitalization, intellectual capital, obtaining prosperity in the market economy imposes a new terminology, new managerial methods and techniques, new technologies and also new strategies. In other words, knowledge based economy, as a new type of economy; impose a new type of management- knowledge based management and a new type of enterprise-knowledge based enterprise.Taking in consideration these predictable evolutions, this paper will try to present: • The main ideas of the researches the field of the knowledge based economy • The characteristics and principles of the knowledge based organizations and knowledge based management • The challenges and opportunities for knowledge based organizations.The first part of the paper will present the principles of the new economy- knowledge base economy, the essential and interrelated elements necessary to build and to implement a strategy in a knowledge economy and the opportunities and challenges to the countries as they seek to build regionally and globally competitive knowledge-based economies.The second part of the paper will present the characteristics of the knowledge based organizations, the principles and characteristics of their management. For many organizations, knowledge management is a relatively new concept, because they are discovering the knowledge value in their operations. Many firms have undertaken formal and informal knowledge management initiatives designed to improve process performance, increase customer responsiveness and spur innovation. But while some organizations have reaped significant benefits from their investment in knowledge efforts, others have run into noteworthy challenges.

  11. Wavelet based error correction and predictive uncertainty of a hydrological forecasting system

    Science.gov (United States)

    Bogner, Konrad; Pappenberger, Florian; Thielen, Jutta; de Roo, Ad

    2010-05-01

    River discharge predictions most often show errors with scaling properties of unknown source and statistical structure that degrade the quality of forecasts. This is especially true for lead-time ranges greater then a few days. Since the European Flood Alert System (EFAS) provides discharge forecasts up to ten days ahead, it is necessary to take these scaling properties into consideration. For example the range of scales for the error that occurs at the spring time will be caused by long lasting snowmelt processes, and is by far larger then the error, that appears during the summer period and is caused by convective rain fields of short duration. The wavelet decomposition is an excellent way to provide the detailed model error at different levels in order to estimate the (unobserved) state variables more precisely. A Vector-AutoRegressive model with eXogenous input (VARX) is fitted for the different levels of wavelet decomposition simultaneously and after predicting the next time steps ahead for each scale, a reconstruction formula is applied to transform the predictions in the wavelet domain back to the original time domain. The Bayesian Uncertainty Processor (BUP) developed by Krzysztofowicz is an efficient method to estimate the full predictive uncertainty, which is derived by integrating the hydrological model uncertainty and the meteorological input uncertainty. A hydrological uncertainty processor has been applied to the error corrected discharge series at first in order to derive the predictive conditional distribution under the hypothesis that there is no input uncertainty. The uncertainty of the forecasted meteorological input forcing the hydrological model is derived from the combination of deterministic weather forecasts and ensemble predictions systems (EPS) and the Input Processor maps this input uncertainty into the output uncertainty under the hypothesis that there is no hydrological uncertainty. The main objective of this Bayesian forecasting system

  12. Practical operation strategies for pumped hydroelectric energy storage (PHES) utilising electricity price arbitrage

    International Nuclear Information System (INIS)

    In this paper, three practical operation strategies (24Optimal, 24Prognostic, and 24Hsitrocial) are compared to the optimum profit feasible for a PHES facility with a 360 MW pump, 300 MW turbine, and a 2 GWh storage utilising price arbitrage on 13 electricity spot markets. The results indicate that almost all (∼97%) of the profits can be obtained by a PHES facility when it is optimised using the 24Optimal strategy developed, which optimises the energy storage based on the day-ahead electricity prices. However, to maximise profits with the 24Optimal strategy, the day-ahead electricity prices must be the actual prices which the PHES facility is charged or the PHES operator must have very accurate price predictions. Otherwise, the predicted profit could be significantly reduced and even become a loss. Finally, using the 24Optimal strategy, the PHES profit can surpass the annual investment repayments required. However, over the 5-year period investigated (2005-2009) the annual profit from the PHES facility varied by more than 50% on five out of six electricity markets considered. Considering the 40-year lifetime of PHES, even with low investment costs, a low interest rate, and a suitable electricity market, PHES is a risky investment without a more predictable profit. - Highlights: → Electricity generators typically operate on a market, including energy storage. → This paper assesses how energy storage can maximise its profits on a market. → Four operating strategies are assessed on 13 markets using a case study.→ One operating strategy achieves 97% of the profits feasible.→ However, the profit varies a lot depending on the market and capital costs.

  13. Pricing in non-convex electricity markets

    Energy Technology Data Exchange (ETDEWEB)

    Araoz Castillo, Veronica

    2012-07-01

    Deregulation of the electricity markets has brought several interesting topics to the research agenda. Switching from a monopoly based industry to the free market industry has not been straight forward. The competitive segments of the deregulated electricity markets, the wholesale market and the retail market, have evolved in different ways across the globe, and consequently there are different market designs and different pricing mechanisms. In a competitive market, the price is given by the intersection of supply and demand. However, electricity treated as a commodity, open to the market forces, has several characteristics that do not fit into the classic economic model where prices are set by the intersection of supply and demand. This is due to non-convexities. This can be a challenge for the price discovery process, since the supply and demand curves may not intersect; or if they intersect, the price found may not be high enough to cover the total cost of production. In the dissertation, Araoz Castillo review previous work on setting prices for the day-ahead electricity market in a power pool auction. In addition, an alternative pricing mechanism is proposed. This mechanism employs a Semi-Lagrangian relaxation technique. This technique provides a price that can be applied in the electricity pool markets. In this type of markets a central system operator decides who produces and how much they should produce. The proposed pricing approach not only accommodates the non-convexities that the electricity market has, but also provides a price for the day-ahead electricity. At this price, the demand is fulfilled at minimum cost and all generators are covering their fixed costs. The technique is applied to a model without networks constraint, with network constraints and also to obtain capacity prices.(Author)

  14. Airborne castanea pollen forecasting model for ecological and allergological implementation.

    Science.gov (United States)

    Astray, G; Fernández-González, M; Rodríguez-Rajo, F J; López, D; Mejuto, J C

    2016-04-01

    Castanea sativa Miller belongs to the natural vegetation of many European deciduous forests prompting impacts in the forestry, ecology, allergological and chestnut food industry fields. The study of the Castanea flowering represents an important tool for evaluating the ecological conservation of North-Western Spain woodland and the possible changes in the chestnut distribution due to recent climatic change. The Castanea pollen production and dispersal capacity may cause hypersensitivity reactions in the sensitive human population due to the relationship between patients with chestnut pollen allergy and a potential cross reactivity risk with other pollens or plant foods. In addition to Castanea pollen's importance as a pollinosis agent, its study is also essential in North-Western Spain due to the economic impact of the industry around the chestnut tree cultivation and its beekeeping interest. The aim of this research is to develop an Artificial Neural Networks for predict the Castanea pollen concentration in the atmosphere of the North-West Spain area by means a 20years data set. It was detected an increasing trend of the total annual Castanea pollen concentrations in the atmosphere during the study period. The Artificial Neural Networks (ANNs) implemented in this study show a great ability to predict Castanea pollen concentration one, two and three days ahead. The model to predict the Castanea pollen concentration one day ahead shows a high linear correlation coefficient of 0.784 (individual ANN) and 0.738 (multiple ANN). The results obtained improved those obtained by the classical methodology used to predict the airborne pollen concentrations such as time series analysis or other models based on the correlation of pollen levels with meteorological variables. PMID:26802339

  15. Solid Base Catalysis

    CERN Document Server

    Ono, Yoshio

    2011-01-01

    The importance of solid base catalysts has come to be recognized for their environmentally benign qualities, and much significant progress has been made over the past two decades in catalytic materials and solid base-catalyzed reactions. The book is focused on the solid base. Because of the advantages over liquid bases, the use of solid base catalysts in organic synthesis is expanding. Solid bases are easier to dispose than liquid bases, separation and recovery of products, catalysts and solvents are less difficult, and they are non-corrosive. Furthermore, base-catalyzed reactions can be performed without using solvents and even in the gas phase, opening up more possibilities for discovering novel reaction systems. Using numerous examples, the present volume describes the remarkable role solid base catalysis can play, given the ever increasing worldwide importance of "green" chemistry. The reader will obtain an overall view of solid base catalysis and gain insight into the versatility of the reactions to whic...

  16. Effects of climate change on water requirements and phenological period of major crops in Heihe River basin, China - Based on the accumulated temperature threshold method

    Science.gov (United States)

    Han, Dongmei; Xu, Xinyi; Yan, Denghua

    2016-04-01

    In recent years, global climate change has significantly caused a serious crisis of water resources throughout the world. However, mainly through variations in temperature, climate change will affect water requirements of crop. It is obvious that the rise of temperature affects growing period and phenological period of crop directly, then changes the water demand quota of crop. Methods including accumulated temperature threshold and climatic tendency rate were adopted, which made up for the weakness of phenological observations, to reveal the response of crop phenological change during the growing period. Then using Penman-Menteith model and crop coefficients from the United Nations Food& Agriculture Organization (FAO), the paper firstly explored crop water requirements in different growth periods, and further forecasted quantitatively crop water requirements in Heihe River Basin, China under different climate change scenarios. Results indicate that: (i) The results of crop phenological change established in the method of accumulated temperature threshold were in agreement with measured results, and (ii) there were many differences in impacts of climate warming on water requirement of different crops. The growth periods of wheat and corn had tendency of shortening as well as the length of growth periods. (ii)Results of crop water requirements under different climate change scenarios showed: when temperature increased by 1°C, the start time of wheat growth period changed, 2 days earlier than before, and the length of total growth period shortened 2 days. Wheat water requirements increased by 1.4mm. However, corn water requirements decreased by almost 0.9mm due to the increasing temperature of 1°C. And the start time of corn growth period become 3 days ahead, and the length of total growth period shortened 4 days. Therefore, the contradiction between water supply and water demands are more obvious under the future climate warming in Heihe River Basin, China.

  17. Electric power systems advanced forecasting techniques and optimal generation scheduling

    CERN Document Server

    Catalão, João P S

    2012-01-01

    Overview of Electric Power Generation SystemsCláudio MonteiroUncertainty and Risk in Generation SchedulingRabih A. JabrShort-Term Load ForecastingAlexandre P. Alves da Silva and Vitor H. FerreiraShort-Term Electricity Price ForecastingNima AmjadyShort-Term Wind Power ForecastingGregor Giebel and Michael DenhardPrice-Based Scheduling for GencosGovinda B. Shrestha and Songbo QiaoOptimal Self-Schedule of a Hydro Producer under UncertaintyF. Javier Díaz and Javie

  18. VectorBase

    Data.gov (United States)

    U.S. Department of Health & Human Services — VectorBase is a Bioinformatics Resource Center for invertebrate vectors. It is one of four Bioinformatics Resource Centers funded by NIAID to provide web-based...

  19. Mobile Inquiry Based Learning

    NARCIS (Netherlands)

    Specht, Marcus

    2012-01-01

    Specht, M. (2012, 8 November). Mobile Inquiry Based Learning. Presentation given at the Workshop "Mobile inquiry-based learning" at the Mobile Learning Day 2012 at the Fernuniversität Hagen, Hagen, Germany.

  20. The ground based plan

    International Nuclear Information System (INIS)

    The paper presents a report of ''The Ground Based Plan'' of the United Kingdom Science and Engineering Research Council. The ground based plan is a plan for research in astronomy and planetary science by ground based techniques. The contents of the report contains a description of:- the scientific objectives and technical requirements (the basis for the Plan), the present organisation and funding for the ground based programme, the Plan, the main scientific features and the further objectives of the Plan. (U.K.)

  1. "Education-based Research"

    DEFF Research Database (Denmark)

    Degn Johansson, Troels

    This paper lays out a concept of education-based research-the production of research knowledge within the framework of tertiary design education-as an integration of problem-based learning and research-based education. This leads to a critique of reflective practice as the primary way to facilitate...... learning at this level, a discussion of the nature of design problems in the instrumentalist tradition, and some suggestions as to how design studies curricula may facilitate education-based research....

  2. Stolen Base Physics

    Science.gov (United States)

    Kagan, David

    2013-01-01

    Few plays in baseball are as consistently close and exciting as the stolen base. While there are several studies of sprinting, the art of base stealing is much more nuanced. This article describes the motion of the base-stealing runner using a very basic kinematic model. The model will be compared to some data from a Major League game. The…

  3. 18 CFR 42.1 - Requirement that Transmission Organizations with Organized Electricity Markets Offer Long-Term...

    Science.gov (United States)

    2010-04-01

    ... transmission right must provide a hedge against day-ahead locational marginal pricing congestion charges or other direct assignment of congestion costs for the period covered and quantity specified....

  4. The power of weather

    OpenAIRE

    Christian Huurman; Francesco Ravazzolo; Chen Zhou

    2010-01-01

    This paper examines the predictive power of weather for electricity prices in day ahead markets in real time. We find that next-day weather forecasts improve the forecast accuracy of Scandinavian day-ahead electricity prices substantially in terms of point forecasts, suggesting that weather forecasts can price the weather premium. This improvement strengthens the confidence in the forecasting model, which results in high center-mass predictive densities. In density forecast, such a predictive...

  5. A hybrid approach to very small scale electrical demand forecasting

    OpenAIRE

    Marinescu, Andrei; Harris, Colin; Dusparic, Ivana; Cahill, Vinny; Clarke, Siobh??n

    2014-01-01

    peer-reviewed Microgrid management and scheduling can considerably benefit from day-ahead demand forecasting. Until now, most of the research in the field of electrical demand forecasting has been done on large-scale systems, such as national or municipal level grids. This paper examines a hybrid method that attempts to accurately estimate day-ahead electrical demand of a small community of houses resembling the load of a single transformer, the equivalent sizing of a ...

  6. Case-based reasoning

    CERN Document Server

    Kolodner, Janet

    1993-01-01

    Case-based reasoning is one of the fastest growing areas in the field of knowledge-based systems and this book, authored by a leader in the field, is the first comprehensive text on the subject. Case-based reasoning systems are systems that store information about situations in their memory. As new problems arise, similar situations are searched out to help solve these problems. Problems are understood and inferences are made by finding the closest cases in memory, comparing and contrasting the problem with those cases, making inferences based on those comparisons, and asking questions whe

  7. Synthetic Base Fluids

    Science.gov (United States)

    Brown, M.; Fotheringham, J. D.; Hoyes, T. J.; Mortier, R. M.; Orszulik, S. T.; Randles, S. J.; Stroud, P. M.

    The chemical nature and technology of the main synthetic lubricant base fluids is described, covering polyalphaolefins, alkylated aromatics, gas-to-liquid (GTL) base fluids, polybutenes, aliphatic diesters, polyolesters, polyalkylene glycols or PAGs and phosphate esters.Other synthetic lubricant base oils such as the silicones, borate esters, perfluoroethers and polyphenylene ethers are considered to have restricted applications due to either high cost or performance limitations and are not considered here.Each of the main synthetic base fluids is described for their chemical and physical properties, manufacture and production, their chemistry, key properties, applications and their implications when used in the environment.

  8. Monitoring Knowledge Base (MKB)

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Monitoring Knowledge Base (MKB) is a compilation of emissions measurement and monitoring techniques associated with air pollution control devices, industrial...

  9. Soy-based polyols

    Science.gov (United States)

    Suppes, Galen; Lozada, Zueica; Lubguban, Arnold

    2013-06-25

    The invention provides processes for preparing soy-based oligomeric polyols or substituted oligomeric polyols, as well as urethane bioelasteromers comprising the oligomeric polyols or substituted oligomeric polyols.

  10. Gasification-based biomass

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2009-01-18

    The gasification-based biomass section of the Renewable Energy Technology Characterizations describes the technical and economic status of this emerging renewable energy option for electricity supply.

  11. XML-BASED REPRESENTATION

    Energy Technology Data Exchange (ETDEWEB)

    R. KELSEY

    2001-02-01

    For focused applications with limited user and use application communities, XML can be the right choice for representation. It is easy to use, maintain, and extend and enjoys wide support in commercial and research sectors. When the knowledge and information to be represented is object-based and use of that knowledge and information is a high priority, then XML-based representation should be considered. This paper discusses some of the issues involved in using XML-based representation and presents an example application that successfully uses an XML-based representation.

  12. Diffusion Based Photon Mapping

    DEFF Research Database (Denmark)

    Schjøth, Lars; Fogh Olsen, Ole; Sporring, Jon

    2007-01-01

    . To address this problem we introduce a novel photon mapping algorithm based on nonlinear anisotropic diffusion. Our algorithm adapts according to the structure of the photon map such that smoothing occurs along edges and structures and not across. In this way we preserve the important illumination features......, while eliminating noise. We call our method diffusion based photon mapping....

  13. Revolutionary Base Spurs Development

    Institute of Scientific and Technical Information of China (English)

    1997-01-01

    MAO Zedong’s Autumn Harvest Uprising spurred not only revolution but development and innovation among the masses. In October 1927, Mao Zedong led troops to Jinggang Mountain, establishing the first revolutionary base. During the 1960s, many young people went to work at Jinggang Mountain and devoted their youth to this revolutionary base. The open-minded and shrewd Tong

  14. Model-based geostatistics

    CERN Document Server

    Diggle, Peter J

    2007-01-01

    Model-based geostatistics refers to the application of general statistical principles of modeling and inference to geostatistical problems. This volume provides a treatment of model-based geostatistics and emphasizes on statistical methods and applications. It also features analyses of datasets from a range of scientific contexts.

  15. Arkansas' Disappearing Tax Base.

    Science.gov (United States)

    Schoppmeyer, Martin; Venters, Tommy

    State legislation that has contributed to the reduction of Arkansas' tax base is described in this paper. Amendment 59, adopted in 1980, has reduced the state tax base by millions of dollars. At the end of 1992, the majority of school districts have equalized their real, personal, and carrier and utility property. Act 34, the current foundation…

  16. Hydrogel based occlusion systems

    NARCIS (Netherlands)

    Stam, F.A.; Jackson, N.; Dubruel, P.; Adesanya, K.; Embrechts, A.; Mendes, E.; Neves, H.P.; Herijgers, P.; Verbrugghe, Y.; Shacham, Y.; Engel, L.; Krylov, V.

    2013-01-01

    A hydrogel based occlusion system, a method for occluding vessels, appendages or aneurysms, and a method for hydrogel synthesis are disclosed. The hydrogel based occlusion system includes a hydrogel having a shrunken and a swollen state and a delivery tool configured to deliver the hydrogel to a tar

  17. Secure base stations

    NARCIS (Netherlands)

    Bosch, Peter; Brusilovsky, Alec; McLellan, Rae; Mullender, Sape; Polakos, Paul

    2009-01-01

    With the introduction of the third generation (3G) Universal Mobile Telecommunications System (UMTS) base station router (BSR) and fourth generation (4G) base stations, such as the 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) Evolved Node B (eNB), it has become important to se

  18. Profile Based Information Retrieval

    Directory of Open Access Journals (Sweden)

    Athar shaikh,

    2011-04-01

    Full Text Available This paper present Profile Based information retrieval system(PBIR. This system provide the user to register with it and based on the users registered areas of interest the system searches the related and efficient information form the world wide web using the technique of web text mining and arranges the unstructured data into structured format and present it to the user. This system also stores the previously searched data and based on users areas of interest and rating awarded to the interest by the user his profile will be updated at particular scheduled time.

  19. QuickBase

    CERN Document Server

    Conner, Nancy

    2007-01-01

    Ready to put Intuit's QuickBase to work? Our new Missing Manual shows you how to capture, modify, share, and manage data and documents with this web-based data-sharing program quickly and easily. No longer do you have to coordinate your team through a blizzard of emails or play frustrating games of "guess which document is the right one."QuickBase saves your organization time and money, letting you manage and share the information that makes your business tick: sales figures, project timelines, drafts of documents, purchase or work requests--whatever information you need to keep business flowi

  20. Data base management study

    Science.gov (United States)

    1976-01-01

    Data base management techniques and applicable equipment are described. Recommendations which will assist potential NASA data users in selecting and using appropriate data base management tools and techniques are presented. Classes of currently available data processing equipment ranging from basic terminals to large minicomputer systems were surveyed as they apply to the needs of potential SEASAT data users. Cost and capabilities projections for this equipment through 1985 were presented. A test of a typical data base management system was described, as well as the results of this test and recommendations to assist potential users in determining when such a system is appropriate for their needs. The representative system tested was UNIVAC's DMS 1100.

  1. Bases de dades relacionals

    OpenAIRE

    Villegas González, Daniel

    2016-01-01

    Les empreses de reclutament de personal han d¿afrontar una sèrie de reptes per les seves tasques diàries, pel gran volum de candidats per cobrir les necessitats del mercat de llocs de treball. RecruitCAT és una empresa de reclutament de personal que necessita gestionar la seva base de dades. El objectiu és dissenyar i implementar una base de dades per gestionar una empresa de reclutament de personal, assolint les tasques d¿estudi, plantejament teòric i els scripts de generació de la base d...

  2. Skull Base Anatomy.

    Science.gov (United States)

    Patel, Chirag R; Fernandez-Miranda, Juan C; Wang, Wei-Hsin; Wang, Eric W

    2016-02-01

    The anatomy of the skull base is complex with multiple neurovascular structures in a small space. Understanding all of the intricate relationships begins with understanding the anatomy of the sphenoid bone. The cavernous sinus contains the carotid artery and some of its branches; cranial nerves III, IV, VI, and V1; and transmits venous blood from multiple sources. The anterior skull base extends to the frontal sinus and is important to understand for sinus surgery and sinonasal malignancies. The clivus protects the brainstem and posterior cranial fossa. A thorough appreciation of the anatomy of these various areas allows for endoscopic endonasal approaches to the skull base.

  3. Design-Based Research

    DEFF Research Database (Denmark)

    Gynther, Karsten; Christensen, Ove; Petersen, Trine Brun

    2012-01-01

    I denne artikel introduceres Design Based Research for første gang på dansk i et videnskabeligt tidsskrift. Artiklen præsenterer de grundlæggende antagelser, som ligger til grund for Design Based Research-traditionen, og artiklen diskuterer de principper, som ligger til grund for gennemførelse af...... et DBR-forskningsprojekt. Med udgangspunkt i forsknings- og udviklingsprojektet ELYK: E-læring, Yderområder og Klyngedannelse, præsenteres den innovationsmodel, som projektet har udviklet med udgangspunkt i Design Based Research traditionen. ELYKs DBR innovationsmodel har vist sig effektiv i forhold...

  4. Lidar base specification

    Science.gov (United States)

    Heidemann, Hans Karl.

    2012-01-01

    In late 2009, a $14.3 million allocation from the “American Recovery and Reinvestment Act” for new light detection and ranging (lidar) elevation data prompted the U.S. Geological Survey (USGS) National Geospatial Program (NGP) to develop a common base specification for all lidar data acquired for The National Map. Released as a draft in 2010 and formally published in 2012, the USGS–NGP “Lidar Base Specification Version 1.0” (now Lidar Base Specification) was quickly embraced as the foundation for numerous state, county, and foreign country lidar specifications.

  5. Language-Based Learning Disabilities

    Science.gov (United States)

    ... Public / Speech, Language and Swallowing / Disorders and Diseases Language-Based Learning Disabilities (Reading, Spelling, and Writing) What ... a language-based learning disability ? What is a language-based learning disability? Language-based learning disabilities are ...

  6. Cheboygan Vessel Base

    Data.gov (United States)

    Federal Laboratory Consortium — Cheboygan Vessel Base (CVB), located in Cheboygan, Michigan, is a field station of the USGS Great Lakes Science Center (GLSC). CVB was established by congressional...

  7. Noncommutative Involutive Bases

    CERN Document Server

    Evans, G A

    2006-01-01

    The theory of Groebner Bases originated in the work of Buchberger and is now considered to be one of the most important and useful areas of symbolic computation. A great deal of effort has been put into improving Buchberger's algorithm for computing a Groebner Basis, and indeed in finding alternative methods of computing Groebner Bases. Two of these methods include the Groebner Walk method and the computation of Involutive Bases. By the mid 1980's, Buchberger's work had been generalised for noncommutative polynomial rings by Bergman and Mora. This thesis provides the corresponding generalisation for Involutive Bases and (to a lesser extent) the Groebner Walk, with the main results being as follows. (1) Algorithms for several new noncommutative involutive divisions are given, including strong; weak; global and local divisions. (2) An algorithm for computing a noncommutative Involutive Basis is given. When used with one of the aforementioned involutive divisions, it is shown that this algorithm returns a noncom...

  8. Problem Based Learning

    DEFF Research Database (Denmark)

    de Graaff, Erik; Guerra, Aida

    Problem-Based Learning (PBL) is an innovative method to organize the learning process in such a way that the students actively engage in finding answers by themselves. During the past 40 years PBL has evolved and diversified resulting in a multitude in variations in models and practices. However...... model and in general problem based and project based learning. We apply the principle of teach as you preach. The poster aims to outline the visitors’ workshop programme showing the results of some recent evaluations......., the key principles remain the same everywhere. Graaff & Kolmos (2003) identify the main PBL principles as follows: 1. Problem orientation 2. Project organization through teams or group work 3. Participant-directed 4. Experiental learning 5. Activity-based learning 6. Interdisciplinary learning and 7...

  9. Mutually unbiased bases

    Indian Academy of Sciences (India)

    S Chaturvedi

    2002-08-01

    After a brief review of the notion of a full set of mutually unbiased bases in an -dimensional Hilbert space, we summarize the work of Wootters and Fields (W K Wootters and B C Fields, Ann. Phys. 191, 363 (1989)) which gives an explicit construction for such bases for the case = r, where is a prime. Further, we show how, by exploiting certain freedom in the Wootters–Fields construction, the task of explicitly writing down such bases can be simplified for the case when is an odd prime. In particular, we express the results entirely in terms of the character vectors of the cyclic group of order . We also analyse the connection between mutually unbiased bases and the representations of .

  10. Kelomehele preemia Baseli festivalil

    Index Scriptorium Estoniae

    2000-01-01

    Baselis festivalil "VIPER - International Festival for Film Video and New Media" tunnistati parimaks CD-ROMiks Gustav Deutschi/Anna Schimeki "Odysee today", netiprojektiks itaallaste "01.ORG", äramärkimispreemia - Raivo Kelomehe "Videoweaver"

  11. WormBase

    Data.gov (United States)

    U.S. Department of Health & Human Services — WormBase is an international consortium of biologists and computer scientists dedicated to providing the research community with accurate, current, accessible...

  12. ACTIVITY - BASED COSTING DESIGNING

    OpenAIRE

    Wioletta Skibiñska; Marta Kad³ubek

    2010-01-01

    The traditional costing system sometimes does not give accurate information about the consumption of different resources and the activities of the organisation. The activity-based costing system is an information-rich costing system which is more and more necessary for the success of many European companies. Base of designing and implementation of an ABC system in the enterprises are presented in the article.

  13. Participatory design based research

    DEFF Research Database (Denmark)

    Dau, Susanne; Bach Jensen, Louise; Falk, Lars

    2014-01-01

    This poster reveal how participatory design based research by the use of a CoED inspired creative process can be used for designing solutions to problems regarding students study activities outside campus.......This poster reveal how participatory design based research by the use of a CoED inspired creative process can be used for designing solutions to problems regarding students study activities outside campus....

  14. Layered nickel based superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Ronning, Filip [Los Alamos National Laboratory; Bauer, Eric D [Los Alamos National Laboratory; Park, Tuson [Los Alamos National Laboratory; Kurita, Nobuyuki [Los Alamos National Laboratory; Klimczuk, T [Los Alamos National Laboratory; Movshovich, R [Los Alamos National Laboratory; Thompson, J D [Los Alamos National Laboratory; Sefat, A S [ORNL; Mandrus, D [ORNL

    2009-01-01

    We review the properties of Ni-based superconductors which contain Ni{sub 2}X{sub 2} (X=As, P, Bi, Si, Ge, B) planes, a common structural element to the recently discovered FeAs superconductors. We also compare the properties ofthe Ni-and Fe-based systems from a perspective ofelectronic structure as well as structure-property relations.

  15. Hydrogel based occlusion systems

    OpenAIRE

    Stam, F.A.; Jackson, N.; Dubruel, P.; Adesanya, K.; Embrechts, A.; Mendes, E.; Neves, H.P.; Herijgers, P.; Verbrugghe, Y.; Shacham, Y; Engel, L.; Krylov, V.

    2013-01-01

    A hydrogel based occlusion system, a method for occluding vessels, appendages or aneurysms, and a method for hydrogel synthesis are disclosed. The hydrogel based occlusion system includes a hydrogel having a shrunken and a swollen state and a delivery tool configured to deliver the hydrogel to a target occlusion location. The hydrogel is configured to permanently occlude the target occlusion location in the swollen state. The hydrogel may be an electro-activated hydrogel (EAH) which could be ...

  16. Evidence-Based Development

    DEFF Research Database (Denmark)

    Hertzum, Morten; Simonsen, Jesper

    2004-01-01

    Systems development is replete with projects that represent substantial resource investments but result in systems that fail to meet users’ needs. Evidence-based development is an emerging idea intended to provide means for managing customer-vendor relationships and working systematically toward...... and electronic patient records for diabetes patients, this paper reports research in progress regarding the prospects and pitfalls of evidence-based development....

  17. Computer-based simulations

    OpenAIRE

    Antonoaie, C.; Antonoaie, N.

    2010-01-01

    A computer-based simulation replicates an environment through a computer program designed to consider multiple variables, interactions, and system constraints. Computer-based simulation is used in organization studies to model human social systems to better understand the dynamics between individual and group behaviours.These methods advance organization studies research in many ways. They can be used for extrapolating theory, validating hypotheses, or revealing emergent behaviour. Simulation...

  18. DSP Based Waveform Generator

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The DSP Based Waveform Generator is used for CSR Control system to control special controlled objects, such as the pulsed power supply for magnets, RF system, injection and extraction synchronization, global CSR synchronization etc. This intelligent controller based on 4800 MIPS DSP and 256M SDRAM technology will supply highly stable and highly accurate reference waveform used by the power supply of magnets. The specifications are as follows:

  19. Compression-based similarity

    OpenAIRE

    Vitányi, Paul

    2011-01-01

    First we consider pair-wise distances for literal objects consisting of finite binary files. These files are taken to contain all of their meaning, like genomes or books. The distances are based on compression of the objects concerned, normalized, and can be viewed as similarity distances. Second, we consider pair-wise distances between names of objects, like "red" or "christianity." In this case the distances are based on searches of the Internet. Such a search can be performed by any search...

  20. REST based mobile applications

    Science.gov (United States)

    Rambow, Mark; Preuss, Thomas; Berdux, Jörg; Conrad, Marc

    2008-02-01

    Simplicity is the major advantage of REST based webservices. Whereas SOAP is widespread in complex, security sensitive business-to-business aplications, REST is widely used for mashups and end-user centric applicatons. In that context we give an overview of REST and compare it to SOAP. Furthermore we apply the GeoDrawing application as an example for REST based mobile applications and emphasize on pros and cons for the use of REST in mobile application scenarios.

  1. LDEF materials data bases

    Science.gov (United States)

    Funk, Joan G.; Strickland, John W.; Davis, John M.

    1993-01-01

    The Long Duration Exposure Facility (LDEF) and the accompanying experiments were composed of and contained a wide variety of materials representing the largest collection of materials flown in low Earth orbit (LEO) and retrieved for ground based analysis to date. The results and implications of the mechanical, thermal, optical, and electrical data from these materials are the foundation on which future LEO space missions will be built. The LDEF Materials Special Investigation Group (MSIG) has been charged with establishing and developing data bases to document these materials and their performance to assure not only that the data are archived for future generations but also that the data are available to the spacecraft user community in an easily accessed, user-friendly form. This paper discusses the format and content of the three data bases developed or being developed to accomplish this task. The hardware and software requirements for each of these three data bases are discussed along with current availability of the data bases. This paper also serves as a user's guide to the MAPTIS LDEF Materials Data Base.

  2. Noncommutative Involutive Bases

    Science.gov (United States)

    Alun Evans, Gareth

    2006-02-01

    The theory of Groebner Bases originated in the work of Buchberger and is now considered to be one of the most important and useful areas of symbolic computation. A great deal of effort has been put into improving Buchberger's algorithm for computing a Groebner Basis, and indeed in finding alternative methods of computing Groebner Bases. Two of these methods include the Groebner Walk method and the computation of Involutive Bases. By the mid 1980's, Buchberger's work had been generalised for noncommutative polynomial rings by Bergman and Mora. This thesis provides the corresponding generalisation for Involutive Bases and (to a lesser extent) the Groebner Walk, with the main results being as follows. (1) Algorithms for several new noncommutative involutive divisions are given, including strong; weak; global and local divisions. (2) An algorithm for computing a noncommutative Involutive Basis is given. When used with one of the aforementioned involutive divisions, it is shown that this algorithm returns a noncommutative Groebner Basis on termination. (3) An algorithm for a noncommutative Groebner Walk is given, in the case of conversion between two harmonious monomial orderings. It is shown that this algorithm generalises to give an algorithm for performing a noncommutative Involutive Walk, again in the case of conversion between two harmonious monomial orderings. (4) Two new properties of commutative involutive divisions are introduced (stability and extendibility), respectively ensuring the termination of the Involutive Basis algorithm and the applicability (under certain conditions) of homogeneous methods of computing Involutive Bases.

  3. On mutually unbiased bases

    CERN Document Server

    Durt, Thomas; Bengtsson, Ingemar; Zyczkowski, Karol \\

    2010-01-01

    Mutually unbiased bases for quantum degrees of freedom are central to all theoretical investigations and practical exploitations of complementary properties. Much is known about mutually unbiased bases, but there are also a fair number of important questions that have not been answered in full as yet. In particular, one can find maximal sets of ${N+1}$ mutually unbiased bases in Hilbert spaces of prime-power dimension ${N=p^\\m}$, with $p$ prime and $\\m$ a positive integer, and there is a continuum of mutually unbiased bases for a continuous degree of freedom, such as motion along a line. But not a single example of a maximal set is known if the dimension is another composite number ($N=6,10,12,...$). In this review, we present a unified approach in which the basis states are labeled by numbers ${0,1,2,...,N-1}$ that are both elements of a Galois field and ordinary integers. This dual nature permits a compact systematic construction of maximal sets of mutually unbiased bases when they are known to exist but th...

  4. Evidence based practice

    DEFF Research Database (Denmark)

    Hjørland, Birger

    2011-01-01

    Evidence-based practice (EBP) is an influential interdisciplinary movement that originated in medicine as evidence-based medicine (EBM) about 1992. EBP is of considerable interest to library and information science (LIS) because it focuses on a thorough documentation of the basis for the decision...... is that practitioners lose their autonomy, that the understanding of theory and of underlying mechanisms is weakened, and that the concept of evidence is too narrow in the empiricist tradition. In this article, it is suggested that we should speak of “research-based practice” rather than EBP, because this term is open...... to more fruitful epistemologies and provides a broader understanding of evidence.The focus on scientific argumentation in EBP is an important contribution from EBP to LIS, which is long overdue, but parts of the underlying epistemological assumptions should be replaced: EBP is too narrow, too formalist...

  5. Nitramine Double Base Propellants

    Directory of Open Access Journals (Sweden)

    M. M. Bhalerao

    1996-10-01

    Full Text Available This review paper broadly covers the studies conducted on nitramine double base (DB propellants, particularly in the field of formulations, evaluation, catalysis and combustion mechanism . Addition of RDX and HMX in double base matrix shows relatively low burn rates and high paper index values. Further, the burn rate of this class of propellants enhances in the presence of energetic binders/plasticisers like glycidyl azide polymer. This paper also discusses the combustion mechanism of HMX/RDX-based DB propellants, especially in the presence of catalytic salts. As scanty data is available on extruded nitramine DB propellants, further work is needed in the field of formulation as well as evaluation with a view to generate exhaustive data.

  6. Classification of base sequences

    CERN Document Server

    Djokovic, Dragomir Z

    2010-01-01

    Base sequences BS(n+1,n) are quadruples of {1,-1}-sequences (A;B;C;D), with A and B of length n+1 and C and D of length n, such that the sum of their nonperiodic autocorrelation functions is a delta-function. The base sequence conjecture, asserting that BS(n+1,n) exist for all n, is stronger than the famous Hadamard matrix conjecture. We introduce a new definition of equivalence for base sequences BS(n+1,n) and construct a canonical form. By using this canonical form, we have enumerated the equivalence classes of BS(n+1,n) for n <= 30. Due to excessive size of the equivalence classes, the tables in the paper cover only the cases n <= 12.

  7. Cantilever Based Mass Sensing

    DEFF Research Database (Denmark)

    Dohn, Søren

    2007-01-01

    Cantilever based mass sensors utilize that a change in vibrating mass will cause a change in the resonant frequency. This can be used for very accurate sensing of adsorption and desorption processes on the cantilever surface. The change in resonant frequency caused by a single molecule depends...... on various parameters including the vibrating mass of the cantilever and the frequency at which it vibrates. The minimum amount of molecules detectable is highly dependent on the noise of the system as well as the method of readout. The aim of this Ph.D. thesis has been twofold: To develop a readout method...... suitable for a portable device and to investigate the possibility of enhancing the functionality and sensitivity of cantilever based mass sensors. A readout method based on the hard contact between the cantilever and a biased electrode placed in close proximity to the cantilever is proposed. The viability...

  8. Inkjet-based micromanufacturing

    CERN Document Server

    Korvink, Jan G; Shin, Dong-Youn; Brand, Oliver; Fedder, Gary K; Hierold, Christofer; Tabata, Osamu

    2012-01-01

    Inkjet-based Micromanufacturing Inkjet technology goes way beyond putting ink on paper: it enables simpler, faster and more reliable manufacturing processes in the fields of micro- and nanotechnology. Modern inkjet heads are per se precision instruments that deposit droplets of fluids on a variety of surfaces in programmable, repeating patterns, allowing, after suitable modifications and adaptations, the manufacturing of devices such as thin-film transistors, polymer-based displays and photovoltaic elements. Moreover, inkjet technology facilitates the large-scale production of flexible RFID tr

  9. Video-based rendering

    CERN Document Server

    Magnor, Marcus A

    2005-01-01

    Driven by consumer-market applications that enjoy steadily increasing economic importance, graphics hardware and rendering algorithms are a central focus of computer graphics research. Video-based rendering is an approach that aims to overcome the current bottleneck in the time-consuming modeling process and has applications in areas such as computer games, special effects, and interactive TV. This book offers an in-depth introduction to video-based rendering, a rapidly developing new interdisciplinary topic employing techniques from computer graphics, computer vision, and telecommunication en

  10. Diffusion Based Photon Mapping

    DEFF Research Database (Denmark)

    Schjøth, Lars; Olsen, Ole Fogh; Sporring, Jon

    2006-01-01

    . To address this problem we introduce a novel photon mapping algorithm based on nonlinear anisotropic diffusion. Our algorithm adapts according to the structure of the photon map such that smoothing occurs along edges and structures and not across. In this way we preserve the important illumination features......Density estimation employed in multi-pass global illumination algorithms give cause to a trade-off problem between bias and noise. The problem is seen most evident as blurring of strong illumination features. In particular this blurring erodes fine structures and sharp lines prominent in caustics......, while eliminating noise. We call our method diffusion based photon mapping....

  11. Identity-based encryption

    CERN Document Server

    Chatterjee, Sanjit

    2011-01-01

    Identity Based Encryption (IBE) is a type of public key encryption and has been intensely researched in the past decade. Identity-Based Encryption summarizes the available research for IBE and the main ideas that would enable users to pursue further work in this area. This book will also cover a brief background on Elliptic Curves and Pairings, security against chosen Cipher text Attacks, standards and more. Advanced-level students in computer science and mathematics who specialize in cryptology, and the general community of researchers in the area of cryptology and data security will find Ide

  12. Animation-based Sketching

    DEFF Research Database (Denmark)

    Vistisen, Peter

    This thesis is based on the results of a three-year long PhD-study at the Department of Communication and Psychology at Aalborg University. The thesis consist of five original papers, a book manuscript, as well as a linking text with the thesis’ research questions, research design, and summary...... experiments has been carried out, applying animation-based sketching in various contexts and at varying points in the design process. In the studies, I evaluate the viability of the approach, the practical integration into the design process, and map how consensus between stakeholders in design can...

  13. Domain based metering

    OpenAIRE

    Párhonyi, Robert; Beijnum, van, Bert-Jan

    2000-01-01

    In the last two years, there is a gaining interest in usage based accounting for the Internet. One of the driving forces for this growing interest is the progress being made in providing some form of quality assurance in IP packet forwarding. One of the key processes in an accounting system is metering, gathering of network usage parameters on which the accounting is or can be based. In this paper are addressed issues that are potentially of interest in Internet accounting. One of these issue...

  14. Game-Based Teaching

    DEFF Research Database (Denmark)

    Hanghøj, Thorkild

    2013-01-01

    This chapter outlines theoretical and empirical perspectives on how Game-Based Teaching can be integrated within the context of formal schooling. Initially, this is done by describing game scenarios as models for possible actions that need to be translated into curricular knowledge practices......, pedagogical knowledge practices, and everyday knowledge practices. Secondly, the chapter emphasizes how teachers must be able to shift back and forth between various interactional roles in order to facilitate game scenarios. Finally, a discussion is presented on how teachers choose different pedagogical...... approaches to game-based teaching, which may or may not correspond with the pedagogical models of particular games....

  15. PROJECT-BASES RISK MANAGEMENT

    OpenAIRE

    Andrei Sandu

    2010-01-01

    The project-bases concept is presented. There are defined operations on project-bases. The software developed for project-bases management is analyzed based in its structure and functionality. A series of criteria of structuring risks is listed are tailored for project-bases management. Next there are suggested solutions of mitigating risks by maintaining efficiency within acceptable thresholds.

  16. Internet based benchmarking

    DEFF Research Database (Denmark)

    Bogetoft, Peter; Nielsen, Kurt

    2005-01-01

    We discuss the design of interactive, internet based benchmarking using parametric (statistical) as well as nonparametric (DEA) models. The user receives benchmarks and improvement potentials. The user is also given the possibility to search different efficiency frontiers and hereby to explore...

  17. BASE - Progress Report 2015

    CERN Document Server

    Ulmer, S; Mooser, A; Sellner, S; Nagahama, H; Higuchi, T; Borchert, M; Schneider, G; Tanaka, T; Blaum, K; Matsuda, Y; Ospelkaus, C; Quint, W; Walz, J; Yamazaki, Y; CERN. Geneva. SPS and PS Experiments Committee; SPSC

    2016-01-01

    The BASE collaboration aims at high-precision comparisons of the fundamental properties of the proton and the antiproton, namely, the magnetic g-factors as well as the charge-to-mass ratios of the particles. This annual report summarizes the achievements made in CERN's 2015 antiproton run.

  18. Model-based consensus

    NARCIS (Netherlands)

    Boumans, Marcel

    2014-01-01

    The aim of the rational-consensus method is to produce “rational consensus”, that is, “mathematical aggregation”, by weighing the performance of each expert on the basis of his or her knowledge and ability to judge relevant uncertainties. The measurement of the performance of the experts is based on

  19. Model-based consensus

    NARCIS (Netherlands)

    M. Boumans

    2014-01-01

    The aim of the rational-consensus method is to produce "rational consensus", that is, "mathematical aggregation", by weighing the performance of each expert on the basis of his or her knowledge and ability to judge relevant uncertainties. The measurement of the performance of the experts is based on

  20. Centroid Based Text Clustering

    Directory of Open Access Journals (Sweden)

    Priti Maheshwari

    2010-09-01

    Full Text Available Web mining is a burgeoning new field that attempts to glean meaningful information from natural language text. Web mining refers generally to the process of extracting interesting information and knowledge from unstructured text. Text clustering is one of the important Web mining functionalities. Text clustering is the task in which texts are classified into groups of similar objects based on their contents. Current research in the area of Web mining is tacklesproblems of text data representation, classification, clustering, information extraction or the search for and modeling of hidden patterns. In this paper we propose for mining large document collections it is necessary to pre-process the web documents and store the information in a data structure, which is more appropriate for further processing than a plain web file. In this paper we developed a php-mySql based utility to convert unstructured web documents into structured tabular representation by preprocessing, indexing .We apply centroid based web clustering method on preprocessed data. We apply three methods for clustering. Finally we proposed a method that can increase accuracy based on clustering ofdocuments.

  1. Performance based fault diagnosis

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik

    2002-01-01

    Different aspects of fault detection and fault isolation in closed-loop systems are considered. It is shown that using the standard setup known from feedback control, it is possible to formulate fault diagnosis problems based on a performance index in this general standard setup. It is also shown...

  2. 80537 based distance relay

    DEFF Research Database (Denmark)

    Pedersen, Knud Ole Helgesen

    1999-01-01

    A method for implementing a digital distance relay in the power system is described.Instructions are given on how to program this relay on a 80537 based microcomputer system.The problem is used as a practical case study in the course 53113: Micocomputer applications in the power system.The relay...

  3. REST based service composition

    DEFF Research Database (Denmark)

    Grönvall, Erik; Ingstrup, Mads; Pløger, Morten;

    2011-01-01

    This paper presents an ongoing work developing and testing a Service Composition framework based upon the REST architecture named SECREST. A minimalistic approach have been favored instead of a creating a complete infrastructure. One focus has been on the system's interaction model. Indeed, an ai...

  4. Aptamer-based nanobiosensors.

    Science.gov (United States)

    Kim, Yeon Seok; Raston, Nurul Hanun Ahmad; Gu, Man Bock

    2016-02-15

    It has been more than two decades since aptamer and the systematic evolution of ligands by exponential enrichment (SELEX) method were discovered by Larry Gold and Andrew Ellington in 1990, respectively. Based on the various advantages of aptamers, they have become a potent rival of antibodies in therapeutics and bio-analysis. Especially, the recent advances in aptamer biosensor application are remarkable due to its intrinsic properties of aptamers as nucleic acids and target induced conformational changes, in addition to the introduction of graphene oxide-based easy and simple immobilization-free screening method even for dual aptamers. In addition, the incorporation of various nanomaterials such as metallic nanoparticles, carbon materials, and functional nanospheres in aptasensors has facilitated the improvement of analytical performance and commercial application of aptasensors. In this review, recent prominent reports on aptasensors utilizing nanomaterials were introduced to understand the principle of aptamer-based biosensors and provide an insight for new strategies of aptasensors and the application of various nanomaterials. The perspective on aptamer-based biosensors and diagnostics was also discussed in view of technology and market. PMID:26139320

  5. Protein Crystal Based Nanomaterials

    Science.gov (United States)

    Bell, Jeffrey A.; VanRoey, Patrick

    2001-01-01

    This is the final report on a NASA Grant. It concerns a description of work done, which includes: (1) Protein crystals cross-linked to form fibers; (2) Engineering of protein to favor crystallization; (3) Better knowledge-based potentials for protein-protein contacts; (4) Simulation of protein crystallization.

  6. XML Based UIScript

    Institute of Scientific and Technical Information of China (English)

    CAI Bin; LIAO Jian-xin; SHEN Qi-wei

    2004-01-01

    In this paper, after the analyzing the UIScript mechanism in intelligent peripheral, a new approach of XML-based UIScript is put forward. The related issues such as the design of UIScript language, the execution environment and its relationship with other script languages are discussed.

  7. Project-Based Science

    Science.gov (United States)

    Krajcik, Joe

    2015-01-01

    Project-based science is an exciting way to teach science that aligns with the "Next Generation Science Standards" ("NGSS"). By focusing on core ideas along with practices and crosscutting concepts, classrooms become learning environments where teachers and students engage in science by designing and carrying out…

  8. Acid-Base Homeostasis.

    Science.gov (United States)

    Hamm, L Lee; Nakhoul, Nazih; Hering-Smith, Kathleen S

    2015-12-01

    Acid-base homeostasis and pH regulation are critical for both normal physiology and cell metabolism and function. The importance of this regulation is evidenced by a variety of physiologic derangements that occur when plasma pH is either high or low. The kidneys have the predominant role in regulating the systemic bicarbonate concentration and hence, the metabolic component of acid-base balance. This function of the kidneys has two components: reabsorption of virtually all of the filtered HCO3(-) and production of new bicarbonate to replace that consumed by normal or pathologic acids. This production or generation of new HCO3(-) is done by net acid excretion. Under normal conditions, approximately one-third to one-half of net acid excretion by the kidneys is in the form of titratable acid. The other one-half to two-thirds is the excretion of ammonium. The capacity to excrete ammonium under conditions of acid loads is quantitatively much greater than the capacity to increase titratable acid. Multiple, often redundant pathways and processes exist to regulate these renal functions. Derangements in acid-base homeostasis, however, are common in clinical medicine and can often be related to the systems involved in acid-base transport in the kidneys.

  9. Problem-Based Learning

    Science.gov (United States)

    Allen, Deborah E.; Donham, Richard S.; Bernhardt, Stephen A.

    2011-01-01

    In problem-based learning (PBL), students working in collaborative groups learn by resolving complex, realistic problems under the guidance of faculty. There is some evidence of PBL effectiveness in medical school settings where it began, and there are numerous accounts of PBL implementation in various undergraduate contexts, replete with…

  10. ISFET based enzyme sensors

    NARCIS (Netherlands)

    Schoot, van der Bart H.; Bergveld, Piet

    1987-01-01

    This paper reviews the results that have been reported on ISFET based enzyme sensors. The most important improvement that results from the application of ISFETs instead of glass membrane electrodes is in the method of fabrication. Problems with regard to the pH dependence of the response and the dyn

  11. Surfel Based Geometry Resonstruction

    DEFF Research Database (Denmark)

    Andersen, Vedrana; Aanæs, Henrik; Bærentzen, Jakob Andreas

    2010-01-01

    We propose a method for retrieving a piecewise smooth surface from noisy data. In data acquired by a scanning process sampled points are almost never on the discontinuities making reconstruction of surfaces with sharp features difficult. Our method is based on a Markov Random Field (MRF) formulat...

  12. Systematic Approach to Better Understanding Integration Costs: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Stark, Gregory B.

    2015-09-28

    When someone mentions integration costs, thoughts of the costs of integrating renewable generation into an existing system come to mind. We think about how variability and uncertainty can increase power system cycling costs as increasing amounts of wind or solar generation are incorporated into the generation mix. However, seldom do we think about what happens to system costs when new baseload generation is added to an existing system or when generation self-schedules. What happens when a highly flexible combined-cycle plant is added? Do system costs go up, or do they go down? Are other, non-cycling, maintenance costs impacted? In this paper we investigate six technologies and operating practices--including VG, baseload generation, generation mix, gas prices, self-scheduling, and fast-start generation--and how changes in these areas can impact a system's operating costs. This paper provides a working definition of integration costs and four components of variable costs. It describes the study approach and how a production cost modeling-based method was used to determine the cost effects, and, as a part of the study approach section, it describes the test system and data used for the comparisons. Finally, it presents the research findings, and, in closing, suggests three areas for future work.

  13. Problem Based Game Design

    DEFF Research Database (Denmark)

    Reng, Lars; Schoenau-Fog, Henrik

    2011-01-01

    At Aalborg University’s department of Medialogy, we are utilizing the Problem Based Learning method to encourage students to solve game design problems by pushing the boundaries and designing innovative games. This paper is concerned with describing this method, how students employ it in various ...... projects and how they learn to analyse, design, and develop for innovation by using it. We will present various cases to exemplify the approach and focus on how the method engages students and aspires for innovation in digital entertainment and games.......At Aalborg University’s department of Medialogy, we are utilizing the Problem Based Learning method to encourage students to solve game design problems by pushing the boundaries and designing innovative games. This paper is concerned with describing this method, how students employ it in various...

  14. Trajectory Based Traffic Analysis

    DEFF Research Database (Denmark)

    Krogh, Benjamin Bjerre; Andersen, Ove; Lewis-Kelham, Edwin;

    2013-01-01

    We present the INTRA system for interactive path-based traffic analysis. The analyses are developed in collaboration with traffic researchers and provide novel insights into conditions such as congestion, travel-time, choice of route, and traffic-flow. INTRA supports interactive point-and-click a......We present the INTRA system for interactive path-based traffic analysis. The analyses are developed in collaboration with traffic researchers and provide novel insights into conditions such as congestion, travel-time, choice of route, and traffic-flow. INTRA supports interactive point......-and-click analysis, due to a novel and efficient indexing structure. With the web-site daisy.aau.dk/its/spqdemo/we will demonstrate several analyses, using a very large real-world data set consisting of 1.9 billion GPS records (1.5 million trajectories) recorded from more than 13000 vehicles, and touching most...

  15. Spintronics-based computing

    CERN Document Server

    Prenat, Guillaume

    2015-01-01

    This book provides a comprehensive introduction to spintronics-based computing for the next generation of ultra-low power/highly reliable logic, which is widely considered a promising candidate to replace conventional, pure CMOS-based logic. It will cover aspects from device to system-level, including magnetic memory cells, device modeling, hybrid circuit structure, design methodology, CAD tools, and technological integration methods. This book is accessible to a variety of readers and little or no background in magnetism and spin electronics are required to understand its content.  The multidisciplinary team of expert authors from circuits, devices, computer architecture, CAD and system design reveal to readers the potential of spintronics nanodevices to reduce power consumption, improve reliability and enable new functionality.  .

  16. Maintaining Relationship Based Procurement

    Directory of Open Access Journals (Sweden)

    Peter Davis

    2012-11-01

    Full Text Available Alliance and relationship projects are increasingin number and represent a large pool of work. Tobe successful relationship style contracts dependon soft-dollar factors, particularly the participants'ability to work together within an agreedframework, generally they are not based on lowbid tendering. Participants should be prepared todo business in an open environment based ontrust and mutually agreed governance. Theresearch evaluates relationship maintenance inthe implementation phase of constructionalliances - a particular derivative of relationshipstyle contracts. To determine the factors thatcontribute to relationship maintenance forty-nineexperienced Australian alliance projectmanagers were interviewed. The main findingswere; the development of relationships early inthe project form building blocks of success fromwhich relationships are maintained and projectvalue added; quality facilitation plays animportant part in relationship maintenance and ahybrid organisation created as a result of alliancedevelopment overcomes destructiveorganisational boundaries. Relationshipmaintenance is integral to alliance project controland failure to formalise it and pay attention toprocess and past outcomes will undermine analliance project's potential for success.

  17. Conducting Polymer Based Nanobiosensors

    Directory of Open Access Journals (Sweden)

    Chul Soon Park

    2016-06-01

    Full Text Available In recent years, conducting polymer (CP nanomaterials have been used in a variety of fields, such as in energy, environmental, and biomedical applications, owing to their outstanding chemical and physical properties compared to conventional metal materials. In particular, nanobiosensors based on CP nanomaterials exhibit excellent performance sensing target molecules. The performance of CP nanobiosensors varies based on their size, shape, conductivity, and morphology, among other characteristics. Therefore, in this review, we provide an overview of the techniques commonly used to fabricate novel CP nanomaterials and their biosensor applications, including aptasensors, field-effect transistor (FET biosensors, human sense mimicking biosensors, and immunoassays. We also discuss prospects for state-of-the-art nanobiosensors using CP nanomaterials by focusing on strategies to overcome the current limitations.

  18. Content Based Video Retrieval

    Directory of Open Access Journals (Sweden)

    B.V.Patel

    2012-11-01

    Full Text Available Content based video retrieval is an approach for facilitating the searching and browsing of large image collections over World Wide Web. In this approach, video analysis is conducted on low level visual properties extracted from video frame. We believed that in order to create an effective video retrieval system, visual perception must be taken into account. We conjectured that a technique which employs multiple features for indexing and retrieval would be more effective in the discrimination and search tasks of videos. In order to validate this claim, content based indexing and retrieval systems were implemented using color histogram, various texture features and other approaches. Videos were stored in Oracle 9i Database and a user study measured correctness of response.

  19. Graphene-based electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Xiao; Zeng, Zhiyuan; Fan, Zhanxi; Liu, Juqing; Zhang, Hua [School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798 (Singapore)

    2012-11-27

    Graphene, the thinnest two dimensional carbon material, has become the subject of intensive investigation in various research fields because of its remarkable electronic, mechanical, optical and thermal properties. Graphene-based electrodes, fabricated from mechanically cleaved graphene, chemical vapor deposition (CVD) grown graphene, or massively produced graphene derivatives from bulk graphite, have been applied in a broad range of applications, such as in light emitting diodes, touch screens, field-effect transistors, solar cells, supercapacitors, batteries, and sensors. In this Review, after a short introduction to the properties and synthetic methods of graphene and its derivatives, we will discuss the importance of graphene-based electrodes, their fabrication techniques, and application areas. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  20. Graphene-based electrodes.

    Science.gov (United States)

    Huang, Xiao; Zeng, Zhiyuan; Fan, Zhanxi; Liu, Juqing; Zhang, Hua

    2012-11-27

    Graphene, the thinnest two dimensional carbon material, has become the subject of intensive investigation in various research fields because of its remarkable electronic, mechanical, optical and thermal properties. Graphene-based electrodes, fabricated from mechanically cleaved graphene, chemical vapor deposition (CVD) grown graphene, or massively produced graphene derivatives from bulk graphite, have been applied in a broad range of applications, such as in light emitting diodes, touch screens, field-effect transistors, solar cells, supercapacitors, batteries, and sensors. In this Review, after a short introduction to the properties and synthetic methods of graphene and its derivatives, we will discuss the importance of graphene-based electrodes, their fabrication techniques, and application areas. PMID:22927209

  1. Sparse approximation with bases

    CERN Document Server

    2015-01-01

    This book systematically presents recent fundamental results on greedy approximation with respect to bases. Motivated by numerous applications, the last decade has seen great successes in studying nonlinear sparse approximation. Recent findings have established that greedy-type algorithms are suitable methods of nonlinear approximation in both sparse approximation with respect to bases and sparse approximation with respect to redundant systems. These insights, combined with some previous fundamental results, form the basis for constructing the theory of greedy approximation. Taking into account the theoretical and practical demand for this kind of theory, the book systematically elaborates a theoretical framework for greedy approximation and its applications.  The book addresses the needs of researchers working in numerical mathematics, harmonic analysis, and functional analysis. It quickly takes the reader from classical results to the latest frontier, but is written at the level of a graduate course and do...

  2. Knowledge based maintenance

    Energy Technology Data Exchange (ETDEWEB)

    Sturm, A. [Hamburgische Electacitaets-Werke AG Hamburg (Germany)

    1997-12-31

    The establishment of maintenance strategies is of crucial significance for the reliability of a plant and the economic efficiency of maintenance measures. Knowledge about the condition of components and plants from the technical and business management point of view therefore becomes one of the fundamental questions and the key to efficient management and maintenance. A new way to determine the maintenance strategy can be called: Knowledge Based Maintenance. A simple method for determining strategies while taking the technical condition of the components of the production process into account to the greatest possible degree which can be shown. A software with an algorithm for Knowledge Based Maintenance leads the user during complex work to the determination of maintenance strategies for this complex plant components. (orig.)

  3. Evidence-based policy

    DEFF Research Database (Denmark)

    Vohnsen, Nina Holm

    2013-01-01

    A current ambition in welfare states as diverse as Denmark, the UK, and in the USA is to base political decision making on rigorous research (Cartwright et al 2009; Mulgan 2009; Bason 2010). Sound as this might seem the ambition has nevertheless been problematized by both policy-makers and the re......A current ambition in welfare states as diverse as Denmark, the UK, and in the USA is to base political decision making on rigorous research (Cartwright et al 2009; Mulgan 2009; Bason 2010). Sound as this might seem the ambition has nevertheless been problematized by both policy...... a full account, see Vohnsen 2011). These insights will be relevant for the anthropological researcher of legislative processes who wishes to move beyond a merely discursive approach to the study of policy and politics....

  4. Flow Based Algorithm

    Directory of Open Access Journals (Sweden)

    T. Karpagam

    2012-01-01

    Full Text Available Problem statement: Network topology design problems find application in several real life scenario. Approach: Most designs in the past either optimize for a single criterion like shortest or cost minimization or maximum flow. Results: This study discussed about solving a multi objective network topology design problem for a realistic traffic model specifically in the pipeline transportation. Here flow based algorithm focusing to transport liquid goods with maximum capacity with shortest distance, this algorithm developed with the sense of basic pert and critical path method. Conclusion/Recommendations: This flow based algorithm helps to give optimal result for transporting maximum capacity with minimum cost. It could be used in the juice factory, milk industry and its best alternate for the vehicle routing problem.

  5. Content Based Video Retrieval

    Directory of Open Access Journals (Sweden)

    B. V. Patel

    2012-10-01

    Full Text Available Content based video retrieval is an approach for facilitating the searching and browsing of large image collections over World Wide Web. In this approach, video analysis is conducted on low level visual properties extracted from video frame. We believed that in order to create an effective video retrieval system, visual perception must be taken into account. We conjectured that a technique which employs multiple features for indexing and retrieval would be more effective in the discrimination and search tasks of videos. In order to validate this claim, content based indexing and retrieval systems were implemented using color histogram, various texture features and other approaches. Videos were stored in Oracle 9i Database and a user study measured correctness of response.

  6. Dictionary Based Image Segmentation

    OpenAIRE

    Dahl, Anders Bjorholm; Dahl, Vedrana Andersen

    2015-01-01

    We propose a method for weakly supervised segmentationof natural images, which may contain both textured or non-texturedregions. Our texture representation is based on a dictionary of imagepatches. To divide an image into separated regions with similar texturewe use an implicit level sets representation of the curve, which makesour method topologically adaptive. In addition, we suggest a multi-labelversion of the method. Finally, we improve upon a similar texture representation,by formulating...

  7. Argument based machine learning

    OpenAIRE

    Možina, Martin

    2014-01-01

    The Thesis presents a novel approach to machine learning, called ABML (argument based machine learning). This approach combines machine learning from examples with some concepts from the field of defeasible argumentation, where arguments are used together with learning examples by learning methods in the induction of a hypothesis. An argument represents a relation between the class value of a particular learning example and its attributes and can be regarded as a partial explanation of this e...

  8. Plasmonics based VLSI processes

    Directory of Open Access Journals (Sweden)

    Shreya Bhattacharya

    2013-04-01

    Full Text Available In continuum to my previous paper titled‘Implementation of plasmonics in VLSI’, this paperattempts to explore further, the actual physicalrealization of an all-plasmonic chip. In this paper,various methods of plasmon-basedphotolithography have been discussed and anobservation is made w.r.t the cost effectiveness andease of adaptability. Also, plasmonics based activeelement has been discussed which would helpunravel further arenas ofapproaches and methodstowards the realization of an all-plasmonic chip.

  9. Graphene-based biosensors

    Science.gov (United States)

    Lebedev, A. A.; Davydov, V. Yu.; Novikov, S. N.; Litvin, D. P.; Makarov, Yu. N.; Klimovich, V. B.; Samoilovich, M. P.

    2016-07-01

    Results of developing and testing graphene-based sensors capable of detecting protein molecules are presented. The biosensor operation was checked using an immunochemical system comprising fluorescein dye and monoclonal antifluorescein antibodies. The sensor detects fluorescein concentration on a level of 1-10 ng/mL and bovine serum albumin-fluorescein conjugate on a level of 1-5 ng/mL. The proposed device has good prospects for use for early diagnostics of various diseases.

  10. Ferrocene base metal chelates

    International Nuclear Information System (INIS)

    Review of the works, devoted to different types of ferrocene metal chelates and to a possibility of ferrocene-containing ligand modification by means of complexing, is presented. Structure, properties and spectral characteristics of transitional metal, rare earth element, Cd2+, UO22+, Th4+ etc. complexes with ferrocene diketones, ferrocene acyl derivatives based on thiosemicarbazones and hydrazones and other heterometal ferrocene-containing metal chelates, are considered. 134 refs., 1 tab

  11. Polysiloxane based neutron detectors

    OpenAIRE

    Dalla Palma, Matteo

    2016-01-01

    In the last decade, neutron detection has been attracting the attention of the scientific community for different reasons. On one side, the increase in the price of 3He, employed in the most efficient and the most widely used neutron detectors. On the other side, the harmfulness of traditional xylene based liquid scintillators, used in extremely large volumes for the detection of fast neutrons. Finally, the demand for most compact and rough systems pushed by the increased popularity of neutro...

  12. Spiritual-based Leadership

    DEFF Research Database (Denmark)

    Pruzan, Peter

    2015-01-01

    Although far from mainstream, the concept of spiritual-based leadership is emerging as an inclusive and yet highly personal approach to leadership that integrates a leader’s inner perspectives on identity, purpose, responsibility and success with her or his decisions and actions in the outer world...... of business—and therefore it is also emerging as a significant framework for understanding, practicing, communicating and teaching the art and profession of leadership....

  13. Onlincolnshire Knowledge Base Collaboration

    OpenAIRE

    Fuller, Ted; Bosworth, Gary; Deville, Jane

    2016-01-01

    This report outlines the Onlincolnshire Knowledge Base Collaboration project undertaken by Lincoln Business School between May 2014 and September 2015. Onlincolnshire is a Lincolnshire County Council-run project which is part-funded by the East Midlands European Regional Development Fund (ERDF) Programme 2007 to 2013. As well as improving the broadband infrastructure, Onlincolnshire delivered a range of support to Lincolnshire’s Small and Medium Sized Enterprises (SMEs) through the “Business...

  14. Instance based function learning

    OpenAIRE

    Ramon, Jan; De Raedt, Luc

    1999-01-01

    The principles of instance based function learning are presented. In IBFL one is given a set of positive examples of a functional predicate. These examples are true ground facts that illustrate the input output behaviour of the predicate. The purpose is then to predict the output of the predicate given a new input. Further assumptions are that there is no background theory and that the inputs and outputs of the predicate consist of structured terms. IBFL is a novel technique that addresses th...

  15. Dictionary Based Image Segmentation

    DEFF Research Database (Denmark)

    Dahl, Anders Bjorholm; Dahl, Vedrana Andersen

    2015-01-01

    We propose a method for weakly supervised segmentation of natural images, which may contain both textured or non-textured regions. Our texture representation is based on a dictionary of image patches. To divide an image into separated regions with similar texture we use an implicit level sets...... in an efficient implementation of our segmentation method. We experimentally validated our approach on a number of natural as well as composed images....

  16. Refrigerator Based on Chemisorption

    Science.gov (United States)

    Jones, Jack A.

    1987-01-01

    Reversible chemical reaction generates pressurized oxygen for cooling. Concept for cryogenic refrigerator based on chemical absorption of oxygen by praseodymium/cerium oxide (PCO) compound. Refrigerator produces cryogenic liquid for cooling infrared sensors. Also used for liquefying air and separating oxygen from nitrogen in air. In chemisorption refrigerator, PCO alternately absorbs and desorbs oxygen depending on whether cooled or heated. One pair of compressors accepts oxygen while others releases it. Compressed oxygen liquefied when precooked and expanded.

  17. MEMS based reference oscillator

    OpenAIRE

    Hedestig, Joel

    2005-01-01

    The interest in tiny wireless applications raises the demand for an integrated reference oscillator with the same performance as the macroscopic quartz crystal reference oscillators. The main challenge of the thesis is to prove that it is possible to build a MEMS based oscillator that approaches the accuracy level of existing quartz crystal oscillators. The MEMS resonator samples which Philips provides are measured and an equivalent electrical model is designed for them. This model is used in...

  18. Evidence based pediatrics.

    OpenAIRE

    Elizabeta ZISOVSKA

    2015-01-01

    It is very difficult to define the entire phrase “Evidence based pediatrics”, covering all components of this overused sentence. The definition comes out of the common sentence and it means integration of the individual clinical expertize together with the best external clinically available evidence of the systematic reviews which are of interest and benefit of the individual patient.Development of clinically appropriate structured question follows PICO model, i.e. containing f...

  19. Lignocellulose-based bioproducts

    CERN Document Server

    Karimi, Keikhosro

    2015-01-01

    This volume provides the technical information required for the production of biofuels and chemicals from lignocellulosic biomass. It starts with a brief overview of the importance, applications, and production processes of different lignocellulosic products. Further chapters review the perspectives of waste-based biofuels and biochemicals; the pretreatment of lignocellulosic biomass for biofuel production; cellulolytic enzyme systems for the hydrolysis of lignocelluloses; and basic and applied aspects of the production of bioethanol, biogas, biohydrogen, and biobutanol from lignocelluloses.

  20. As bases do petismo

    Directory of Open Access Journals (Sweden)

    David Samuels

    2004-10-01

    Full Text Available A partir dos dados do ESEB de 2002 o autor realiza um estudo das bases eleitorais do PT e de hipóteses sobre a natureza do petismo. Através de técnicas estatísticas multivariadas, são testadas relações do petismo com variáveis demográficas, socioeconômicas e variáveis relativas a questões políticas específicas. Os resultados apontam que apenas a escolaridade tem uma associação específica com o petismo, com implicações para o seu comportamento sócio-político.Based on the results of the 2002 Brazilian Electoral Study, the author analyses the electoral bases of the Worker´s Party and the factors associated with the "petismo". The relationships between the "petismo"and the socioeconomic, demographic and political variables are tested using multivariate analysis. The results indicate that the only "social category"associated with "petismo"is level of education, and it has clear implications to their social and political behavior.

  1. Microbead agglutination based assays

    KAUST Repository

    Kodzius, Rimantas

    2013-01-21

    We report a simple and rapid room temperature assay for point-of-care (POC) testing that is based on specific agglutination. Agglutination tests are based on aggregation of microbeads in the presence of a specific analyte thus enabling the macroscopic observation. Such tests are most often used to explore antibody-antigen reactions. Agglutination has been used for protein assays using a biotin/streptavidin system as well as a hybridization based assay. The agglutination systems are prone to selftermination of the linking analyte, prone to active site saturation and loss of agglomeration at high analyte concentrations. We investigated the molecular target/ligand interaction, explaining the common agglutination problems related to analyte self-termination, linkage of the analyte to the same bead instead of different microbeads. We classified the agglutination process into three kinds of assays: a two- component assay, a three-component assay and a stepped three- component assay. Although we compared these three kinds of assays for recognizing DNA and protein molecules, the assay can be used for virtually any molecule, including ions and metabolites. In total, the optimized assay permits detecting analytes with high sensitivity in a short time, 5 min, at room temperature. Such a system is appropriate for POC testing.

  2. Molecule-based magnets

    Indian Academy of Sciences (India)

    J V Yakhmi

    2009-06-01

    The conventional magnetic materials used in current technology, such as, Fe, Fe2O3, Cr2O3, SmCo5, Nd2Fe14B etc are all atom-based, and their preparation/processing require high temperature routes. Employing self-assembly methods, it is possible to engineer a bulk molecular material with long-range magnetic order, mainly because one can play with the weak intermolecular interactions. Since the first successful synthesis of molecular magnets in 1986, a large variety of them have been synthesized, which can be categorized on the basis of the chemical nature of the magnetic units involved: organic-, metal-based systems, heterobimetallic assemblies, or mixed organic–inorganic systems. The design of molecule-based magnets has also been extended to the design of poly-functional molecular magnets, such as those exhibiting second-order optical nonlinearity, liquid crystallinity, or chirality simultaneously with long-range magnetic order. Solubility, low density and biocompatibility are attractive features of molecular magnets. Being weakly coloured, unlike their opaque classical magnet ‘cousins’ listed above, possibilities of photomagnetic switching exist. Persistent efforts also continue to design the ever-elusive polymer magnets towards applications in industry. While providing a brief overview of the field of molecular magnetism, this article highlights some recent developments in it, with emphasis on a few studies from the author’s own lab.

  3. Lunar base initiative 1992

    Science.gov (United States)

    Koelle, H. H.

    The return to the Moon is no longer a question of yes or no, but a question of when and how. The first landing of a human being on the lunar surface in 1969 was a purely national effort of the U.S.A. Building a lunar base and operating it in the next century is rather a task for all nations of this planet, even if one nation could do it alone. However, there are several alternatives to carry out such a program and these will and should be debated during the next years on an urgent basis. To do this, one has to take into account not only the historical accomplishments and the present trends of cooperation in space programs, but also recent geopolitical developments as well as the frame of reference established by international law. The case for an International Lunar Base (ILB) has been presented to the International Academy of Astronautics on 11 October 1987 by the IAA Ad Hoc Committee "Return-to-the-Moon". This draft of a position paper was subsequently published in Acta Astronautica Vol. 17, No. 5, (pp. 463-489) with the request of public debate particularly by the members of the Academy. Some 80 Academicians responded to this invitation by the President of the Academy and voiced their opinions on the questions and issues raised by this draft of a position paper. This led to a refinement of the arguments and assumptions made and it is now possible to prepare an improved position paper proposing concrete steps which may lead to an ILB. An issue of this proportion must start with a discussion of goals and objectives to be arranged in some kind of a ranked order. It also has to take note of the limitations existing at any time by the availability of suitable space transportation systems. These will determine the acquisition date and rate of growth of a lunar base. The logistics system will also greatly influence the base characteristics and layout. The availability of heavy lift launch vehicles would simplify the task and allow to concentrate the construction

  4. Polyolefin-Based Aerogels

    Science.gov (United States)

    Lee, Je Kyun; Gould, George

    2012-01-01

    An organic polybutadiene (PB) rubberbased aerogel insulation material was developed that will provide superior thermal insulation and inherent radiation protection, exhibiting the flexibility, resiliency, toughness, and durability typical of the parent polymer, yet with the low density and superior insulation properties associated with the aerogels. The rubbery behaviors of the PB rubber-based aerogels are able to overcome the weak and brittle nature of conventional inorganic and organic aerogel insulation materials. Additionally, with higher content of hydrogen in their structure, the PB rubber aerogels will also provide inherently better radiation protection than those of inorganic and carbon aerogels. Since PB rubber aerogels also exhibit good hydrophobicity due to their hydrocarbon molecular structure, they will provide better performance reliability and durability as well as simpler, more economic, and environmentally friendly production over the conventional silica or other inorganic-based aerogels, which require chemical treatment to make them hydrophobic. Inorganic aerogels such as silica aerogels demonstrate many unusual and useful properties. There are several strategies to overcoming the drawbacks associated with the weakness and brittleness of silica aerogels. Development of the flexible fiber-reinforced silica aerogel composite blanket has proven one promising approach, providing a conveniently fielded form factor that is relatively robust toward handling in industrial environments compared to silica aerogel monoliths. However, the flexible silica aerogel composites still have a brittle, dusty character that may be undesirable, or even intolerable, in certain applications. Although the cross-linked organic aerogels such as resorcinol-formaldehyde (RF), polyisocyanurate, and cellulose aerogels show very high impact strength, they are also very brittle with little elongation (i.e., less rubbery). Also, silica and carbon aerogels are less efficient

  5. Characteristics Data Base

    International Nuclear Information System (INIS)

    The LWR Serial Numbers Database System (SNDB) contains detailed data about individual, historically discharged LWR spent fuel assemblies. This data includes the reactor where used, the year the assemblies were discharged, the pool where they are currently stored, assembly type, burnup, weight, enrichment, and an estimate of their radiological properties. This information is distributed on floppy disks to users in the nuclear industry to assist in planning for the permanent nuclear waste repository. This document describes the design and development of the SNDB. It provides a complete description of the file structures and an outline of the major code modules. It serves as a reference for a programmer maintaining the system, or for others interested in the technical detail of this database. This is the initial version of the SNDB. It contains historical data through December 31, 1987, obtained from the Energy Information Administration (EIA). EIA obtains the data from the utility companies via the RW-859 Survey Form. It evaluates and standardizes the data and distributes the resulting batch level database as a large file on magnetic tape. The Characteristics Data Base obtains this database for use in the LWR Quantities Data Base. Additionally, the CDB obtains the individual assembly level detail from EIA for use in the SNDB. While the Quantities Data Base retains only the level of detail necessary for its reporting, the SNDB does retain and use the batch level data to assist in the identification of a particular assembly serial number. We expect to update the SNDB on an annual basis, as new historical data becomes available

  6. Agent-Based Optimization

    CERN Document Server

    Jędrzejowicz, Piotr; Kacprzyk, Janusz

    2013-01-01

    This volume presents a collection of original research works by leading specialists focusing on novel and promising approaches in which the multi-agent system paradigm is used to support, enhance or replace traditional approaches to solving difficult optimization problems. The editors have invited several well-known specialists to present their solutions, tools, and models falling under the common denominator of the agent-based optimization. The book consists of eight chapters covering examples of application of the multi-agent paradigm and respective customized tools to solve  difficult optimization problems arising in different areas such as machine learning, scheduling, transportation and, more generally, distributed and cooperative problem solving.

  7. Speckle-based wavemeter

    DEFF Research Database (Denmark)

    Hanson, Steen Grüner; Jakobsen, Michael Linde; Chakrabarti, Maumita

    2015-01-01

    A spectrometer based on the application of dynamic speckles will be disclosed. The method relies on scattering of primarily coherent radiation from a slanted rough surface. The scattered radiation is collected on a detector array and the speckle displacement is monitored during a change in the...... incident wavelength. The change of wavelength gives an almost linear phaseshift across the scattering surface resulting in an almost linear shift of the speckle pattern, which is subsequently monitored. It is argued that frequency changes close to 100 MHz can be probed using a common CMOS array...

  8. Commonality based interoperability

    Science.gov (United States)

    Moulton, Christine L.; Hepp, Jared J.; Harrell, John

    2016-05-01

    What interoperability is and why the Army wants it between systems is easily understood. Enabling multiple systems to work together and share data across boundaries in a co-operative manner will benefit the warfighter by allowing for easy access to previously hard-to-reach capabilities. How to achieve interoperability is not as easy to understand due to the numerous different approaches that accomplish the goal. Commonality Based Interoperability (CBI) helps establish how to achieve the goal by extending the existing interoperability definition. CBI is not an implementation, nor is it an architecture; it is a definition of interoperability with a foundation of establishing commonality between systems.

  9. Cellular based cancer vaccines

    DEFF Research Database (Denmark)

    Hansen, Morten; Met, O; Svane, I M;

    2012-01-01

    Cancer vaccines designed to re-calibrate the existing host-tumour interaction, tipping the balance from tumor acceptance towards tumor control holds huge potential to complement traditional cancer therapies. In general, limited success has been achieved with vaccines composed of tumor...... in vitro migration via autocrine receptor-mediated endocytosis of CCR7. In the current review, we discuss optimal design of DC maturation focused on pre-clinical as well as clinical results from standard and polarized dendritic cell based cancer vaccines....

  10. Refractive index based measurements

    DEFF Research Database (Denmark)

    2014-01-01

    In a method for performing a refractive index based measurement of a property of a fluid such as chemical composition or temperature by observing an apparent angular shift in an interference fringe pattern produced by back or forward scattering interferometry, ambiguities in the measurement caused...... by the apparent shift being consistent with one of a number of numerical possibilities for the real shift which differ by 2n are resolved by combining measurements performed on the same sample using light paths therethrough of differing lengths....

  11. COMPUTER BASED ENVIRONMENT CONTROLS

    OpenAIRE

    Macoveiciuc Pastorel

    2011-01-01

    The aim of these notes is to give an overview of the main activities of computer based activities controls. The basic principles of computer controls should be common to all sectors and to most types of hardware and software. The absence of a common definition of computer control may, in part, be due to the relative newness of computer controls. A key feature of many organisations today is change. Although not necessarily the driver of change, IT is invariably an intrinsec component and much ...

  12. WAP - based telemedicine applications

    International Nuclear Information System (INIS)

    Telemedicine refers to the utilization of telecommunication technology for medical diagnosis, treatment, and patient care. Its aim is to provide expert-based health care to remote sites through telecommunication and information technologies. The significant advances in technologies have enabled the introduction of a broad range of telemedicine applications, which are supported by computer networks, wireless communication, and information superhighway. For example, some hospitals are using tele-radiology for remote consultation. Such a system includes medical imaging devices networked with computers and databases. Another growing area is patient monitoring, in which sensors are used to acquire biomedical signals, such as electrocardiogram (ECG), blood pressure, and body temperature, from a remote patient, who could be in bed or moving freely. The signals are then relayed to remote systems for viewing and analysis. Telemedicine can be divided into two basic modes of operations: real-time mode, in which the patient data can be accessed remotely in real-time, and store-and-forward mode, in which the acquired data does not have to be accessed immediately. In the recent years, many parties have demonstrated various telemedicine applications based on the Internet and cellular phone as these two fields have been developing rapidly. A current, recognizable trend in telecommunication is the convergence of wireless communication and computer network technologies. This has been reflected in recently developed telemedicine systems. For example, in 1998 J. Reponen, et al. have demonstrated transmission and display of computerized tomography (CT) examinations using a remote portable computer wirelessly connected to a computer network through TCP/IP on a GSM cellular phone. Two years later, they carried out the same tests with a GSM-based wireless personal digital assistant (PDA). The WAP (Wireless Application Protocol) Forum was founded in 1997 to create a global protocol

  13. Wood-Based Bioenergy

    OpenAIRE

    Hoel, Michael; Sletten, Thea Marcelia

    2014-01-01

    During recent years increased attention has been given to second-generation wood-based bioenergy. The carbon stored in the forest is highest when there is little or no harvest from the forest. Increasing the harvest from a forest, in order to produce more bioenergy, may thus conflict with the direct benefit of the forest as a carbon sink. We analyze this conflict using a simple model where bioenergy and fossil energy are perfect substitutes. Our analysis shows how the social optimum will depe...

  14. LIGHTWEIGHT CONCRETE BASED GRANSHLAK

    Directory of Open Access Journals (Sweden)

    NETESA M. I.

    2016-02-01

    Full Text Available Raising of problem. Concrete advisable to obtain a low strength with local secondary resources for recycling and reduce the environmental burden on the environment. But it is important to design such concrete compositions with a reduced flow of cement. It is known that the coefficient of efficiency of use of cement in the concrete of the heavy and B10 is less than about 0.5, which is almost two times smaller than in class B15 concrete and above. Even lower coefficient of efficiency in light concrete cement low strength. Therefore, it is important to find patterns determining the composition of lightweight concrete based on local-products industry with more efficient use of cement in them. Purpose.. Based on the analysis of earlier research results, including with the use of methods of mathematical planning of experiments to determine the concrete contents, which can provide the requirements for the underlying layers of the floor, the compressive strength of which should correspond to the class B5. It is important to provide the required strength at minimum flow of the cement, which is the most expensive and energy-intensive part of concrete. Conclusion. Analysis of the test results of control samples of concrete in 28-day-old, the following laws. The required tensile strength of concrete compressive strength of 7.0 MPa can be obtained in the test range when used in formulations as a filler as the Dnieper hydroelectric power station fly ash and tailings Krivoy Rog iron ore YuGOK. To ensure providing the required characteristic strength of the concrete in the underlying layers of the floor is advisable to use a nominal composition per cubic meter of concrete: cement 160 kg granshlaka Plant named after Petrovsky, 675 kg of fly ash Dnieper HPP 390 kg, 400 kg of sand, 230 liters of water. Thus, while ensuring rational grain composition components can obtain the desired strength lightweight concrete based granshlaka plant Petrovsky, using as fillers

  15. RF Based Spy

    OpenAIRE

    Robot Prerna Jain; Pallavi N. Firke

    2014-01-01

    The intention of this paper is to reduce human victims in terrorist attack such as 26/11. So this problem can be overcome by designing the RF based spy robot which involves wireless camera. so that from this we can examine rivals when it required. This robot can quietly enter into enemy area and sends us the information via wireless camera. On the other hand one more feature is added in this robot that is colour sensor. Colour sensor senses the colour of surface and according ...

  16. Teradata data base computer

    Energy Technology Data Exchange (ETDEWEB)

    1984-04-01

    To meet the growing demand for information management of large databases, Teradata Corporation has introduced the DBC/1012 data base computer, an IBM plug-compatible system that can handle data volumes up to a trillion bytes. Teradata estimates the DBC/1012 to be one-third the cost of an all-software relational system on a general purpose mainframe. Cost effectiveness, as well as fault tolerance, is achieved by a parallel architecture which processes data asynchronously using multiple independent microprocessors. Another cost saving results from the resources on the host mainframe that become available once the mainframe is relieved of the burden of maintaining the database.

  17. Sustainability Base Construction Update

    Science.gov (United States)

    Mewhinney, Michael

    2012-01-01

    Construction of the new Sustainability Base Collaborative support facility, expected to become the highest performing building in the federal government continues at NASA's Ames Research Center, Moffet Field, Calif. The new building is designed to achieve a platinum rating under the leadership in Energy and Environment Design (LEED) new construction standards for environmentally sustainable construction developed by the U. S. Green Building Council, Washington, D. C. When completed by the end of 2011, the $20.6 million building will feature near zero net energy consumption, use 90 percent less potable water than conventionally build buildings of equivalent size, and will result in reduced building maintenance costs.

  18. Bi-based superconductor

    Directory of Open Access Journals (Sweden)

    S E Mousavi

    2009-08-01

    Full Text Available   In this paper, Bi-Sr-Ca-Cu-O (BCSCCO system superconductor is made by the solid state reaction method. The effect of doping Pb, Cd, Sb, Cu and annealing time on the critical temperature and critical current density have been investigated. The microstructure and morphology of the samples have been studied by X-ray diffraction, scanning electron microscope and energy dispersive X-ray. The results show that the fraction of Bi-2223 phase in the Bi- based superconductor, critical temperature and critical current density depend on the annealing temperature, annealing time and the kind and amount of doping .

  19. Knowledge based Entrepreneurship

    DEFF Research Database (Denmark)

    Heebøll, John

    This book is dedicated enterprising people with a technical or a scientific background who consider commercializing ideas and inventions within their field of expertise via a new business activity or a new company. It aims at distilling experiences from many successful and not so successful start......-up ventures from the Technical University of Denmark, 1988 – 2008 into practical, portable knowledge that can be used by future knowledge-based entrepreneurs to set up new companies efficiently or to stay away from it; to do what’s needed and avoid the pitfalls....

  20. Vision-based interaction

    CERN Document Server

    Turk, Matthew

    2013-01-01

    In its early years, the field of computer vision was largely motivated by researchers seeking computational models of biological vision and solutions to practical problems in manufacturing, defense, and medicine. For the past two decades or so, there has been an increasing interest in computer vision as an input modality in the context of human-computer interaction. Such vision-based interaction can endow interactive systems with visual capabilities similar to those important to human-human interaction, in order to perceive non-verbal cues and incorporate this information in applications such

  1. Pitch Based Sound Classification

    OpenAIRE

    Nielsen, Andreas Brinch; Hansen, Lars Kai; Kjems, U.

    2006-01-01

    A sound classification model is presented that can classify signals into music, noise and speech. The model extracts the pitch of the signal using the harmonic product spectrum. Based on the pitch estimate and a pitch error measure, features are created and used in a probabilistic model with soft-max output function. Both linear and quadratic inputs are used. The model is trained on 2 hours of sound and tested on publicly available data. A test classification error below 0.05 with 1 s classif...

  2. Moon base reactor system

    Science.gov (United States)

    Chavez, H.; Flores, J.; Nguyen, M.; Carsen, K.

    1989-01-01

    The objective of our reactor design is to supply a lunar-based research facility with 20 MW(e). The fundamental layout of this lunar-based system includes the reactor, power conversion devices, and a radiator. The additional aim of this reactor is a longevity of 12 to 15 years. The reactor is a liquid metal fast breeder that has a breeding ratio very close to 1.0. The geometry of the core is cylindrical. The metallic fuel rods are of beryllium oxide enriched with varying degrees of uranium, with a beryllium core reflector. The liquid metal coolant chosen was natural lithium. After the liquid metal coolant leaves the reactor, it goes directly into the power conversion devices. The power conversion devices are Stirling engines. The heated coolant acts as a hot reservoir to the device. It then enters the radiator to be cooled and reenters the Stirling engine acting as a cold reservoir. The engines' operating fluid is helium, a highly conductive gas. These Stirling engines are hermetically sealed. Although natural lithium produces a lower breeding ratio, it does have a larger temperature range than sodium. It is also corrosive to steel. This is why the container material must be carefully chosen. One option is to use an expensive alloy of cerbium and zirconium. The radiator must be made of a highly conductive material whose melting point temperature is not exceeded in the reactor and whose structural strength can withstand meteor showers.

  3. Design Based Wilderness Education

    Directory of Open Access Journals (Sweden)

    Christopher R. Saulnier

    2015-02-01

    Full Text Available The Massachusetts Institute of Technology (MIT has been collaborating since 2010 with the Singapore Ministry of Education to help develop the Singapore University of Technology and Design (SUTD. One element of this collaboration, the Global Leadership Program (GLP, aims to provide SUTD students with the opportunity to interact with the MIT community and experience MIT’s academic culture. During GLP students participate in a program designed to develop leadership ability while also increasing their understanding of engineering science and design thinking. This paper introduces a curriculum combining the pedagogies of design-based learning and wilderness education that was implemented in the summer of 2014 to holistically address the development of these three competencies. Through design-based learning activities, both for and in a natural environment, students were encouraged to develop competencies in engineering science and engineering design while exploring the diverse attributes essential for success as an engineer. This paper examines the results of a retrospective post-then-pre survey administered to the participants upon completion of the program to explore the effects of the program on the development of professional engineering competencies. We find a statistically significant increase in items associated with Individual Leadership Skill, Group Leadership Skill and the role of Society and the Economy. These results are triangulated with student exit interviews and instructor observations.

  4. Model Based Definition

    Science.gov (United States)

    Rowe, Sidney E.

    2010-01-01

    In September 2007, the Engineering Directorate at the Marshall Space Flight Center (MSFC) created the Design System Focus Team (DSFT). MSFC was responsible for the in-house design and development of the Ares 1 Upper Stage and the Engineering Directorate was preparing to deploy a new electronic Configuration Management and Data Management System with the Design Data Management System (DDMS) based upon a Commercial Off The Shelf (COTS) Product Data Management (PDM) System. The DSFT was to establish standardized CAD practices and a new data life cycle for design data. Of special interest here, the design teams were to implement Model Based Definition (MBD) in support of the Upper Stage manufacturing contract. It is noted that this MBD does use partially dimensioned drawings for auxiliary information to the model. The design data lifecycle implemented several new release states to be used prior to formal release that allowed the models to move through a flow of progressive maturity. The DSFT identified some 17 Lessons Learned as outcomes of the standards development, pathfinder deployments and initial application to the Upper Stage design completion. Some of the high value examples are reviewed.

  5. Microlaser-based displays

    Science.gov (United States)

    Bergstedt, Robert; Fink, Charles G.; Flint, Graham W.; Hargis, David E.; Peppler, Philipp W.

    1997-07-01

    Laser Power Corporation has developed a new type of projection display, based upon microlaser technology and a novel scan architecture, which provides the foundation for bright, extremely high resolution images. A review of projection technologies is presented along with the limitations of each and the difficulties they experience in trying to generate high resolution imagery. The design of the microlaser based projector is discussed along with the advantage of this technology. High power red, green, and blue microlasers have been designed and developed specifically for use in projection displays. These sources, in combination with high resolution, high contrast modulator, produce a 24 bit color gamut, capable of supporting the full range of real world colors. The new scan architecture, which reduces the modulation rate and scan speeds required, is described. This scan architecture, along with the inherent brightness of the laser provides the fundamentals necessary to produce a 5120 by 4096 resolution display. The brightness and color uniformity of the display is excellent, allowing for tiling of the displays with far fewer artifacts than those in a traditionally tiled display. Applications for the display include simulators, command and control centers, and electronic cinema.

  6. Constraint-based reachability

    Directory of Open Access Journals (Sweden)

    Arnaud Gotlieb

    2013-02-01

    Full Text Available Iterative imperative programs can be considered as infinite-state systems computing over possibly unbounded domains. Studying reachability in these systems is challenging as it requires to deal with an infinite number of states with standard backward or forward exploration strategies. An approach that we call Constraint-based reachability, is proposed to address reachability problems by exploring program states using a constraint model of the whole program. The keypoint of the approach is to interpret imperative constructions such as conditionals, loops, array and memory manipulations with the fundamental notion of constraint over a computational domain. By combining constraint filtering and abstraction techniques, Constraint-based reachability is able to solve reachability problems which are usually outside the scope of backward or forward exploration strategies. This paper proposes an interpretation of classical filtering consistencies used in Constraint Programming as abstract domain computations, and shows how this approach can be used to produce a constraint solver that efficiently generates solutions for reachability problems that are unsolvable by other approaches.

  7. Challenge Based Innovation gala

    CERN Document Server

    CERN. Geneva; Utriainen, Tuuli Maria; Toivonen, Harri; Nordberg, Markus

    2014-01-01

    Challenge Based Innovation gala   There’s a new experiment starting in CERN called IdeaLab where we work together with detector R&D researchers to help them to bridge their knowledge into a more human, societally oriented context. Currently we are located in B153, but will move our activities to a new facility next to the Globe in May 2014. One of our first pilot projects is a 5 month course CBI (Challenge Based Innovation) where two multidisciplinary student teams join forces with Edusafe & TALENT projects at CERN. Their goal is to discover what kind of tools for learning could be created in collaboration with the two groups. After months of user interviews and low resolution prototyping they are ready to share the results with us in the form of an afternoon gala. We warmly welcome you to join us to see the students' results and experience the prototypes they have conceived. The event is in three parts, you are welcome to visit all of them,...

  8. Knowledge Based Economy Assessment

    Directory of Open Access Journals (Sweden)

    Madalina Cristina Tocan

    2012-12-01

    Full Text Available The importance of knowledge-based economy (KBE in the XXI century isevident. In the article the reflection of knowledge on economy is analyzed. The main point is targeted to the analysis of characteristics of knowledge expression in economy and to the construction of structure of KBE expression. This allows understanding the mechanism of functioning of knowledge economy. Theauthors highlight the possibility to assess the penetration level of KBE which could manifest itself trough the existence of products of knowledge expression which could be created in acquisition, creation, usage and development of them. The latter phenomenon is interpreted as knowledge expression characteristics: economic and social context, human resources, ICT, innovative business and innovation policy. The reason for this analysis was based on the idea that in spite of the knowledge economy existence in all developed World countries adefinitive, universal list of indicators for mapping and measuring the KBE does not yet exists. Knowledge Expression Assessment Models are presented in the article.

  9. BIOMETRICS BASED USER AUTHENTICATION

    Directory of Open Access Journals (Sweden)

    Tanuj Tiwari

    2015-10-01

    Full Text Available Biometrics is automated methods of recognizing a person based on a physiological or behavioral characteristic. Biometrics technologies are base for a plethora of highly secure identification and personal verification solutions. It is measurement of biological characteristics – either physiological or behavioral – that verify the claimed identity of an individual. Physiological biometrics include fingerprints, iris recognition. voice verification, retina recognition, palm vein patterns, finger vein patterns, hand geometry and DNA But there arises a need for more robust systems in order to tackle the increasing incidents of security breaches and frauds. So there is always a need for fool proof technology that can provide security and safety to individuals and the transactions that the individuals make. Biometrics is increasingly used by organizations to verify identities, but coupled with quantum cryptography it offers a new range of security benefits with quantum cryptography where we form a key when we need it and then destroy it. In this paper, we give a brief overview of the field of biometrics and summarize some of its advantages, disadvantages, strengths, limitations, and related privacy concerns.

  10. MS Based Metabonomics

    Energy Technology Data Exchange (ETDEWEB)

    Want, Elizabeth J.; Metz, Thomas O.

    2010-03-01

    Metabonomics is the latest and least mature of the systems biology triad, which also includes genomics and proteomics, and has its origins in the early orthomolecular medicine work pioneered by Linus Pauling and Arthur Robinson. It was defined by Nicholson and colleagues in 1999 as the quantitative measurement of perturbations in the metabolite complement of an integrated biological system in response to internal or external stimuli, and is often used today to describe many non-global types of metabolite analyses. Applications of metabonomics are extensive and include toxicology, nutrition, pharmaceutical research and development, physiological monitoring and disease diagnosis. For example, blood samples from millions of neonates are tested routinely by mass spectrometry (MS) as a diagnostic tool for inborn errors of metabolism. The metabonome encompasses a wide range of structurally diverse metabolites; therefore, no single analytical platform will be sufficient. Specialized sample preparation and detection techniques are required, and advances in NMR and MS technologies have led to enhanced metabonome coverage, which in turn demands improved data analysis approaches. The role of MS in metabonomics is still evolving as instrumentation and software becomes more sophisticated and as researchers realize the strengths and limitations of current technology. MS offers a wide dynamic range, high sensitivity, and reproducible, quantitative analysis. These attributes are essential for addressing the challenges of metabonomics, as the range of metabolite concentrations easily exceeds nine orders of magnitude in biofluids, and the diversity of molecular species ranges from simple amino and organic acids to lipids and complex carbohydrates. Additional challenges arise in generating a comprehensive metabolite profile, downstream data processing and analysis, and structural characterization of important metabolites. A typical workflow of MS-based metabonomics is shown in Figure

  11. Mucin-Based Vaccines

    Science.gov (United States)

    Richardson, Jonathan P.; MacMillan, Derek

    Mucins are heavily O-glycosylated cell surface and secreted glycoproteins . In addition to orchestrating cell-extracellular matrix and cell-cell interactions in healthy organisms mucins are also the major carriers of altered glycosylation in carcinomas. Tumor-associated antigens displayed by cancer cells comprise oligosaccharide and glycopeptide motifs not encountered in the same locale or at the same frequency in healthy cells, and potentially confer a selective advantage to the tumor. Frequently tumor-associated antigens are under-glycosylated and prematurely sialylated, and it is these relatively simple saccharide and glycopeptide structures that have been targeted to serve as drug candidates in most cases. A major goal is to assemble glycopeptide vaccine candidates based on partial mucin sequences and displaying tumor-associated antigens that can mount a potent immunological tumor-specific response when, in reality, the tumor has already coerced the immune system into a state of co-existence.

  12. Pitch Based Sound Classification

    DEFF Research Database (Denmark)

    Nielsen, Andreas Brinch; Hansen, Lars Kai; Kjems, U

    2006-01-01

    A sound classification model is presented that can classify signals into music, noise and speech. The model extracts the pitch of the signal using the harmonic product spectrum. Based on the pitch estimate and a pitch error measure, features are created and used in a probabilistic model with soft......-max output function. Both linear and quadratic inputs are used. The model is trained on 2 hours of sound and tested on publicly available data. A test classification error below 0.05 with 1 s classification windows is achieved. Further more it is shown that linear input performs as well as a quadratic......, and that even though classification gets marginally better, not much is achieved by increasing the window size beyond 1 s....

  13. Fiber based optofluidic biosensors

    Science.gov (United States)

    Lismont, M.; Vandewalle, N.; Joris, B.; Dreesen, L.

    2014-09-01

    Medicinal diagnosis requires the development of innovative devices allowing the detection of small amounts of biological species. Among the large variety of available biosensors, the ones based on fluorescence phenomenon are really promising. Here, we show a prototype of the basic unit of a multi-sensing biosensor combining optics and microfluidics benefits. This unit makes use of two crossed optical fibers: the first fiber is used to carry small probe molecules droplets and excite fluorescence, while the second one is devoted to target molecules droplets transport and fluorescence detection. Within this scheme, the interaction takes place in each fiber node. The main benefits of this detection setup are the absence of fibers functionalization, the use of microliter volumes of target and probe species, their separation before interaction, and a better detection limit compared to cuvettes setups.

  14. Diffusion Based Photon Mapping

    DEFF Research Database (Denmark)

    Schjøth, Lars; Sporring, Jon; Fogh Olsen, Ole

    2008-01-01

    . To address this problem, we introduce a photon mapping algorithm based on nonlinear anisotropic diffusion. Our algorithm adapts according to the structure of the photon map such that smoothing occurs along edges and structures and not across. In this way, we preserve important illumination features, while......Density estimation employed in multi-pass global illumination algorithms give cause to a trade-off problem between bias and noise. The problem is seen most evident as blurring of strong illumination features. In particular, this blurring erodes fine structures and sharp lines prominent in caustics...... eliminating noise. We demonstrate the applicability of our algorithm through a series of tests. In the tests, we evaluate the visual and computational performance of our algorithm comparing it to existing popular algorithms. Udgivelsesdato: December...

  15. Touching base with OPERA

    CERN Multimedia

    CERN Bulletin

    2011-01-01

    Three seminars – at CERN, at Gran Sasso and in Japan – and an article calling for the scrutiny of the scientific community: the OPERA Collaboration opened its research publicly. In addition to huge press coverage, this triggered welcome reactions from colleagues around the world, many of whom will attempt to independently interpret and reproduce the measurement. OPERA’s Spokesperson touches base with the Bulletin.   The CERN Main Auditorium was crowded as OPERA Physics co-ordinator Dario Autiero presented the results of their research (23 September 2011). According to the OPERA strategy, the results of the measurements are in the hands of the scientific community and, as for any other scientific result, several months will be needed before other groups will be able to perform an independent measurement. In the meantime, the OPERA Collaboration is dealing with an avalanche of emails from the scientific community, members of the general public, and the press. &...

  16. Base isolation: Fresh insight

    Energy Technology Data Exchange (ETDEWEB)

    Shustov, V.

    1993-07-15

    The objective of the research is a further development of the engineering concept of seismic isolation. Neglecting the transient stage of seismic loading results in a widespread misjudgement: The force of resistance associated with velocity is mostly conceived as a source of damping vibrations, though it is an active force at the same time, during an earthquake type excitation. For very pliant systems such as base isolated structures with relatively low bearing stiffness and with artificially added heavy damping mechanism, the so called `damping`` force may occur even the main pushing force at an earthquake. Thus, one of the two basic pillars of the common seismic isolation philosophy, namely, the doctrine of usefulness and necessity of a strong damping mechanism, is turning out to be a self-deception, sometimes even jeopardizing the safety of structures and discrediting the very idea of seismic isolation. There is a way out: breaking with damping dependancy.

  17. Location-based Scheduling

    DEFF Research Database (Denmark)

    Andersson, Niclas; Christensen, Knud

    The coordination of activities and resources in order to establish an effective production flow is central to the management of construction projects. The traditional technique for coordination of activities and resources in construction projects is the CPM-scheduling, which has been the predomin......The coordination of activities and resources in order to establish an effective production flow is central to the management of construction projects. The traditional technique for coordination of activities and resources in construction projects is the CPM-scheduling, which has been...... on the market. However, CPM is primarily an activity based method that takes the activity as the unit of focus and there is criticism raised, specifically in the case of construction projects, on the method for deficient management of construction work and continuous flow of resources. To seek solutions...

  18. Bases para proyectiles dirigidos

    Directory of Open Access Journals (Sweden)

    Editorial, Equipo

    1959-03-01

    Full Text Available Aunque actualmente no se ha llegado a una línea general de métodos o sistemas que gobiernen un tipo característico de rampa y servicios auxiliares necesarios para el lanzamiento al espacio de proyectiles dirigidos a grandes alturas y distancias, las experiencias obtenidas en diferentes ensayos, utilizando distintos tipos de proyectiles y trayectorias balísticas, han sentado toda una serie de procedimientos, datos y conclusiones de gran valor balístico que, aun teniendo en cuenta la continua evolución del proyectil, sus formas, combustibles y alcances, se conocen ya, con bastante aproximación, las condiciones mínimas que ha de reunir una base dedicada a este tipo de lanzamientos.

  19. Al - BASED CAST COMPOSITES

    Directory of Open Access Journals (Sweden)

    Rakesh Kumar Yadav

    2011-08-01

    Full Text Available The economy is very important feature nowadays in themarket. The researches are playing an important role inengineering field to increase the life of machine parts /components and decrease the cost. The compositematerials have the potential to replace widely used steeland aluminium due to their good characteristics withbetter performance. The Al-based composites have foundextensive applications in automobile industries andaerospace industries due to their increased stiffness,strength, thermal conductivity and wear resistanceproperties. A number of particulate phases have beenemployed in the Al-alloy matrix. The cast aluminiumceramicparticulate composites are finding applications inpistons, connecting rods, cylinder liner, engine cylinderblock, electrical contacts etc.The present investigation isbased on study of the effect of particulate phase on theSEM study, micro-hardness, elastic modulus, tensilestrength and the wear behaviour of Al-5 % SiC-7 % Fe,Al-10 % SiC-6 % Fe and Al-15 % SiC-5 % Fe composites.

  20. The office based CHIVA

    Directory of Open Access Journals (Sweden)

    Passariello F

    2013-09-01

    Full Text Available Fausto Passariello,1 Stefano Ermini,2 Massimo Cappelli,3 Roberto Delfrate,4 Claude Franceschi5 1Centro Diagnostico Aquarius, Napoli, Italy; 2Private Practice, Grassina, Italy; 3Private Practice, Firenze, Italy; 4Casa di Cure Figlie di Maria, Cremona, Italy; 5Hospital St Joseph, Service d'Explorations Vasculaires, Paris, France Abstract: The cure Conservatrice Hémodynamique de l'Insuffisance Veineuse en Ambulatoire (CHIVA can be office based (OB. The OB-CHIVA protocol is aimed at transferring CHIVA procedures to specialists rooms. The protocol will check the feasibility of OB-CHIVA, data pertaining to recurrence, and will offer the opportunity to study saphenous femoral junction (SFJ stump evolution, the role of the washing vessels and the arch recanalization rate, and gather new data about the effect of the length of the treated saphenous vein. A simplified diagnostic procedure will allow an essential ultrasound examination of the venous net while a schematic and easily readable algorithm guides therapeutic choices. The Riobamba draining crossotomy (RDC tactic is composed of a set of OB procedures. While some of these procedures are, at the moment, only proposals, others are already applied. Devices generally used in ablative procedures such as Light Amplification by Stimulated Emission of Radiation (LASER, radio frequency, steam, and mechanical devices are used in this context to serve to conservative interventions for CHIVA. New techniques have also been proposed for devalvulation and tributary disconnection. Detailed follow-up is necessary in order to determine the effects of therapy and possible disease evolution. Finally, information is added about the informed consent and the ethical considerations of OB-CHIVA research. Keywords: CHIVA, office based procedures, LASER, RF, steam

  1. Base Research Program

    Energy Technology Data Exchange (ETDEWEB)

    Everett Sondreal; John Hendrikson

    2009-03-31

    In June 2009, the Energy & Environmental Research Center (EERC) completed 11 years of research under the U.S. Department of Energy (DOE) Base Cooperative Agreement No. DE-FC26-98FT40320 funded through the Office of Fossil Energy (OFE) and administered at the National Energy Technology Laboratory (NETL). A wide range of diverse research activities were performed under annual program plans approved by NETL in seven major task areas: (1) resource characterization and waste management, (2) air quality assessment and control, (3) advanced power systems, (4) advanced fuel forms, (5) value-added coproducts, (6) advanced materials, and (7) strategic studies. This report summarizes results of the 67 research subtasks and an additional 50 strategic studies. Selected highlights in the executive summary illustrate the contribution of the research to the energy industry in areas not adequately addressed by the private sector alone. During the period of performance of the agreement, concerns have mounted over the impact of carbon emissions on climate change, and new programs have been initiated by DOE to ensure that fossil fuel resources along with renewable resources can continue to supply the nation's transportation fuel and electric power. The agreement has addressed DOE goals for reductions in CO{sub 2} emissions through efficiency, capture, and sequestration while expanding the supply and use of domestic energy resources for energy security. It has further contributed to goals for near-zero emissions from highly efficient coal-fired power plants; environmental control capabilities for SO{sub 2}, NO{sub x}, fine respirable particulate (PM{sub 2.5}), and mercury; alternative transportation fuels including liquid synfuels and hydrogen; and synergistic integration of fossil and renewable resources (e.g., wind-, biomass-, and coal-based electrical generation).

  2. Usability Issues in Content Based Multimedia Computer Based Trainings

    OpenAIRE

    Khan, Muhammad Qasim; Rehman, Zia ur

    2009-01-01

    In distance education, students and teachers are at different places and interact with each other with the help of different technologies. Broadcast television, two-way video conferencing, asynchronous learning mode, virtual learning environment (VLE) and content based multimedia computer based trainings (CB-MCBTs) are some of the technologies used to provide distance education. Content Based Multimedia Computer Based Trainings (CB-MCBT) is a computerized learning environment. The acceptance ...

  3. DUAL BASES FOR A NEW FAMILY OF GENERALIZED BALL BASES

    Institute of Scientific and Technical Information of China (English)

    Hong-yiWu

    2004-01-01

    This paper presents the dual bases for a new family of generalized Ball curves with a position parameter K, which includes the Bezier curve, generalized Said-Ball curve and some intermediate curves. Using the dual bases, the relative Marsden identity, conversion formulas of bases and control points of various curves are obtained.

  4. 基于改进细菌群体趋药性算法的风 -蓄 -火联合调度的研究

    Institute of Scientific and Technical Information of China (English)

    付伟

    2015-01-01

    由于风电功率波动性大,直接接入电网会给电网安全运行带来很大的风险. 针对风电出力的随机性,在风电预测的基础上,结合抽水蓄能削峰填谷的特点,提出了风-蓄-火联合系统日前和时前调度策略,日前调度阶段以风—蓄—火联合调度获取最大经济效益为目标函数,采用改进的细菌群体趋药性算法进行优化,得到风、蓄、火的日前出力计划. 时前调度阶段对日前阶段的机组出力进行修正,首先在满足抽水蓄能、满足约束条件的情况下,修正抽水蓄能的出力,再修正火电机组的出力,修正目标是以火电机组的运行成本最小. 最后,以含风电场的算例对该模型进行了验证,仿真结果表明了所提出的调度策略具有一定的可行性.%Because the wind power has a severe fluctuation, and it can bring great risk to the safety of power grid if it is direct-ly connected to power grid.According to the randomness of wind power, based on the wind power prediction and combined with the characteristics of the pumped storage, a two-stage coordinated joint dispatch strategy for wind farm and pumped-storage power station is proposed, which is consisted of day-ahead dispatch and hour-ahead dispatch.The day-ahead dis-patching model takes the maximum economic benefits of the wind-storage-thermal joint operation as the objective, and it is optimized by the improved bacterial colony chemotaxis algorithm, so the day-ahead output of wind -storage-thermal is known.In hour-ahead dispatch stage, according to the results of short-term wind power prediction the planning power is constantly revised.Firstly, based on the satisfied constraint condition of pumped-storage unit, the output of pumped-stor-age unit is revised.Secondly, the output of thermoelectric generating set is revised.The objective is to make the cost of the operation of thermoelectric generating set minimum.Finally, the model is verified by an example containing

  5. The Activity-Based Approach

    OpenAIRE

    McNally, Michael G.; Rindt, Craig

    2008-01-01

    What is the activity-based approach (ABA) and how does it differ from the conventional trip-based model of travel behavior? From where has the activity approach evolved, what is its current status, and what are its potential applications in transportation forecasting and policy analysis. What have been the contributions of activity-based approaches to understanding travel behavior? The conventional trip-based model of travel demand forecasting (see Chapters 2 and 3) has always lacked...

  6. ‘"Education-based Research"

    DEFF Research Database (Denmark)

    Degn Johansson, Troels

    This paper lays out a concept of education-based research-the production of research knowledge within the framework of tertiary design education-as an integration of problem-based learning and research-based education. This leads to a critique of reflective practice as the primary way to facilitate...... learning at this level, a discussion of the nature of design problems in the instrumentalist tradition, and some suggestions as to how design studies curricula may facilitate education-based research....

  7. Identity-based ring signature scheme based on quadratic residues

    Institute of Scientific and Technical Information of China (English)

    Xiong Hu; Qin Zhiguang; Li Fagen

    2009-01-01

    Identity-based (ID-based) ring signature has drawn great concerns in recent years and many ID-based ring signature schemes have been proposed until now. Unfortunately, all of these ID-based ring signatures are constructed from bilinear pairings, a powerful but computationally expensive primitive. Hence, ID-based ring signature without pairing is of great interest in the field of cryptography. In this paper, the authors firstly propose an ID-based ring signature scheme based on quadratic residues. The proposed scheme is proved to be existentially unforgeable against adaptive chosen message-and-identity attack under the random oracle model, assuming the hardness of factoring. The proposed scheme is more efficient than those which are constructed from bilinear pairings.

  8. Managing the Gap between Curriculum Based and Problem Based Learning

    DEFF Research Database (Denmark)

    Bygholm, Ann; Buus, Lillian

    2009-01-01

    /or but rather both/and. In this paper we describe an approach to design and delivery of online courses in computer science which on the one hand is based on a specified curriculum and on the other hand gives room for different learning strategies, problem based learning being one of them. We discuss......Traditionally there has been a clear distinction between curriculum based and problem based approaches to accomplish learning. Preferred approaches depend of course on conviction, culture, traditions and also on the specific learning situation. We will argue that it is not a question of either...... the challenges in applying problem based learning strategies in a context where several universities, with different cultures of teaching, collaboratively develop and deliver online courses. We present a pedagogical framework embracing both problem based and curriculum based strategies and show how we used...

  9. Explanation-Based Auditing

    CERN Document Server

    Fabbri, Daniel

    2011-01-01

    To comply with emerging privacy laws and regulations, it has become common for applications like electronic health records systems (EHRs) to collect access logs, which record each time a user (e.g., a hospital employee) accesses a piece of sensitive data (e.g., a patient record). Using the access log, it is easy to answer simple queries (e.g., Who accessed Alice's medical record?), but this often does not provide enough information. In addition to learning who accessed their medical records, patients will likely want to understand why each access occurred. In this paper, we introduce the problem of generating explanations for individual records in an access log. The problem is motivated by user-centric auditing applications, and it also provides a novel approach to misuse detection. We develop a framework for modeling explanations which is based on a fundamental observation: For certain classes of databases, including EHRs, the reason for most data accesses can be inferred from data stored elsewhere in the da...

  10. Electroencephalography-based monitors

    Directory of Open Access Journals (Sweden)

    Nidhi Gupta

    2015-01-01

    Full Text Available An electroencephalogram (EEG, detects changes and abnormalities in the electrical activity of the brain and thus provides a way to dynamically assess brain function. EEG may be used to diagnose and manage a number of clinical conditions such as epilepsy, convulsive and non-convulsive status epilepticus, encephalitis, barbiturate coma, brain death, etc., EEG provides a large amount of information to the anaesthesiologist for routine clinical practice as depth of anaesthesia monitors and detection of sub-clinical seizures; and also for understanding the complex mechanisms of anaesthesia-induced alteration of consciousness. In the initial years, the routine clinical applicability of EEG was hindered by the complexity of the raw EEG signal. However, with technological advancement, several EEG-derived dimensionless indices have been developed that correlate with the depth of the hypnotic component of anaesthesia and are easy to interpret. Similarly, with the development of quantitative EEG tools, the routine use of continuous EEG is ever expanding in the Intensive Care Units. This review, describe various commonly used EEG-based monitors and their clinical applicability in the field of anaesthesia and critical care.

  11. RF Based Spy

    Directory of Open Access Journals (Sweden)

    Robot Prerna Jain

    2014-04-01

    Full Text Available The intention of this paper is to reduce human victims in terrorist attack such as 26/11. So this problem can be overcome by designing the RF based spy robot which involves wireless camera. so that from this we can examine rivals when it required. This robot can quietly enter into enemy area and sends us the information via wireless camera. On the other hand one more feature is added in this robot that is colour sensor. Colour sensor senses the colour of surface and according to that robot will change its colour. Because of this feature this robot can’t easily detected by enemies. The movement of this robot is wirelessly controlled by a hand held RF transmitter to send commands to the RF receiver mounted on the moving robot. Since human life is always Valueable, these robots are the substitution of soldiers in war areas. This spy robot can also be used in star hotels, shopping malls, jewelry show rooms, etc where there can be threat from intruders or terrorists.

  12. Geovisualization based upon KML

    Directory of Open Access Journals (Sweden)

    Marianna Zichar

    2012-06-01

    Full Text Available The extension kml refers to a human readable file format that is based on a markup language deriving from XML and became rather popular mainly due to Google Earth. This type of files uses not only the classical geometric data, but coordinates of longitude and latitude (in case of 3D system also coordinate of altitude to visualize the different geographically referenced objects, phenomena and processes. Nowadays more than 10 millions of kml files can be accessed via the internet, and this number is still increasing. However, knowledge of the standard features of kml is not always sufficient, because the circumstances of its application influence its usage. The functionality of the APIs for the web-embeddable Google Maps and Google Earth programs is determinative concerning this issue. The elements of the standard KML cannot be always used without any change, but the clever usage of the API can result effective tools of dynamism. My aim is to review how wide the range of kml files application is, to describe their differences and to share some personal experiences.

  13. Mixture Based Outlier Filtration

    Directory of Open Access Journals (Sweden)

    P. Pecherková

    2006-01-01

    Full Text Available Success/failure of adaptive control algorithms – especially those designed using the Linear Quadratic Gaussian criterion – depends on the quality of the process data used for model identification. One of the most harmful types of process data corruptions are outliers, i.e. ‘wrong data’ lying far away from the range of real data. The presence of outliers in the data negatively affects an estimation of the dynamics of the system. This effect is magnified when the outliers are grouped into blocks. In this paper, we propose an algorithm for outlier detection and removal. It is based on modelling the corrupted data by a two-component probabilistic mixture. The first component of the mixture models uncorrupted process data, while the second models outliers. When the outlier component is detected to be active, a prediction from the uncorrupted data component is computed and used as a reconstruction of the observed data. The resulting reconstruction filter is compared to standard methods on simulated and real data. The filter exhibits excellent properties, especially in the case of blocks of outliers. 

  14. Alphavirus-Based Vaccines

    Directory of Open Access Journals (Sweden)

    Kenneth Lundstrom

    2014-06-01

    Full Text Available Alphavirus vectors have demonstrated high levels of transient heterologous gene expression both in vitro and in vivo and, therefore, possess attractive features for vaccine development. The most commonly used delivery vectors are based on three single-stranded encapsulated alphaviruses, namely Semliki Forest virus, Sindbis virus and Venezuelan equine encephalitis virus. Alphavirus vectors have been applied as replication-deficient recombinant viral particles and, more recently, as replication-proficient particles. Moreover, in vitro transcribed RNA, as well as layered DNA vectors have been applied for immunization. A large number of highly immunogenic viral structural proteins expressed from alphavirus vectors have elicited strong neutralizing antibody responses in multispecies animal models. Furthermore, immunization studies have demonstrated robust protection against challenges with lethal doses of virus in rodents and primates. Similarly, vaccination with alphavirus vectors expressing tumor antigens resulted in prophylactic protection against challenges with tumor-inducing cancerous cells. As certain alphaviruses, such as Chikungunya virus, have been associated with epidemics in animals and humans, attention has also been paid to the development of vaccines against alphaviruses themselves. Recent progress in alphavirus vector development and vaccine technology has allowed conducting clinical trials in humans.

  15. Holography based super resolution

    Science.gov (United States)

    Hussain, Anwar; Mudassar, Asloob A.

    2012-05-01

    This paper describes the simulation of a simple technique of superresolution based on holographic imaging in spectral domain. The input beam assembly containing 25 optical fibers with different orientations and positions is placed to illuminate the object in the 4f optical system. The position and orientation of each fiber is calculated with respect to the central fiber in the array. The positions and orientations of the fibers are related to the shift of object spectrum at aperture plane. During the imaging process each fiber is operated once in the whole procedure to illuminate the input object transparency which gives shift to the object spectrum in the spectral domain. This shift of the spectrum is equal to the integral multiple of the pass band aperture width. During the operation of single fiber (ON-state) all other fibers are in OFF-state at that time. The hologram recorded by each fiber at the CCD plane is stored in computer memory. At the end of illumination process total 25 holograms are recorded by the whole fiber array and by applying some post processing and specific algorithm single super resolved image is obtained. The superresolved image is five times better than the band-limited image. The work is demonstrated using computer simulation only.

  16. Scintillator based beta batteries

    Science.gov (United States)

    Rensing, Noa M.; Tiernan, Timothy C.; Shirwadkar, Urmila; O'Dougherty, Patrick; Freed, Sara; Hawrami, Rastgo; Squillante, Michael R.

    2013-05-01

    Some long-term, remote applications do not have access to conventional harvestable energy in the form of solar radiation (or other ambient light), wind, environmental vibration, or wave motion. Radiation Monitoring Devices, Inc. (RMD) is carrying out research to address the most challenging applications that need power for many months or years and which have undependable or no access to environmental energy. Radioisotopes are an attractive candidate for this energy source, as they can offer a very high energy density combined with a long lifetime. Both large scale nuclear power plants and radiothermal generators are based on converting nuclear energy to heat, but do not scale well to small sizes. Furthermore, thermo-mechanical power plants depend on moving parts, and RTG's suffer from low efficiency. To address the need for compact nuclear power devices, RMD is developing a novel beta battery, in which the beta emissions from a radioisotope are converted to visible light in a scintillator and then the visible light is converted to electrical power in a photodiode. By incorporating 90Sr into the scintillator SrI2 and coupling the material to a wavelength-matched solar cell, we will create a scalable, compact power source capable of supplying milliwatts to several watts of power over a period of up to 30 years. We will present the latest results of radiation damage studies and materials processing development efforts, and discuss how these factors interact to set the operating life and energy density of the device.

  17. Securing web-based exams

    NARCIS (Netherlands)

    Sessink, O.D.T.; Beeftink, H.H.; Tramper, J.; Hartog, R.J.M.

    2004-01-01

    Learning management systems may offer web-based exam facilities. Such facilities entail a higher risk to exams fraud than traditional paper-based exams. The article discusses security issues with web-based exams, and proposes precautionary measures to reduce the risks. A security model is presented

  18. PMIS: Data Base Design Report

    Science.gov (United States)

    Fiddleman, Richard; Gorman, Michael M.

    1972-01-01

    PMIS is a computer-based planning and management information system for local school districts. This report centers on the PMIS data bases that contain school system data by reviewing the major phases involved in their creation, explaining the factors that caused the unique orientation of the data bases, reviewing the two tasks that comprise the…

  19. Image Data Bases on Campus.

    Science.gov (United States)

    Kaplan, Reid; Mathieson, Gordon

    1989-01-01

    A description of how image database technology was used to develop two prototypes for academic and administrative applications at Yale University, one using a video data base integration and the other using document-scanning data base technology, is presented. Technical underpinnings for the creation of data bases are described. (Author/MLW)

  20. Wind power forecasting accuracy and uncertainty in Finland

    Energy Technology Data Exchange (ETDEWEB)

    Holttinen, H.; Miettinen, J.; Sillanpaeae, S.

    2013-04-15

    Wind power cannot be dispatched so the production levels need to be forecasted for electricity market trading. Lower prediction errors mean lower regulation balancing costs, since relatively less energy needs to go through balance settlement. From the power system operator point of view, wind power forecast errors will impact the system net imbalances when the share of wind power increases, and more accurate forecasts mean less regulating capacity will be activated from the real time Regulating Power Market. In this publication short term forecasting of wind power is studied mainly from a wind power producer point of view. The forecast errors and imbalance costs from the day-ahead Nordic electricity markets are calculated based on real data from distributed wind power plants. Improvements to forecasting accuracy are presented using several wind forecast providers, and measures for uncertainty of the forecast are presented. Aggregation of sites lowers relative share of prediction errors considerably, up to 60%. The balancing costs were also reduced up to 60%, from 3 euro/MWh for one site to 1-1.4 euro/MWh to aggregate 24 sites. Pooling wind power production for balance settlement will be very beneficial, and larger producers who can have sites from larger geographical area will benefit in lower imbalance costs. The aggregation benefits were already significant for smaller areas, resulting in 30-40% decrease in forecast errors and 13-36% decrease in unit balancing costs, depending on the year. The resulting costs are strongly dependent on Regulating Market prices that determine the prices for the imbalances. Similar level of forecast errors resulted in 40% higher imbalance costs for 2012 compared with 2011. Combining wind forecasts from different Numerical Weather Prediction providers was studied with different combination methods for 6 sites. Averaging different providers' forecasts will lower the forecast errors by 6% for day-ahead purposes. When combining

  1. Comparison of control systems for the optimisation of ice storage in a dynamic real time electricity pricing environment

    International Nuclear Information System (INIS)

    Highlights: • A cold thermal energy storage system model was created and validated. • Pseudo real time electricity pricing was derived to represent the smart grid. • A demand side management optimisation algorithm was developed. • Demand side management algorithm performance was compared to a standard controller. • Overall the demand side management algorithm produced modest cost savings. - Abstract: The objective of this study was to assess the benefits of introducing a demand side management optimisation controller to a cold thermal storage ice bank. This controller consisted of an ice bank model, an air temperature forecast model and an optimisation algorithm. The financial and grid utilisation benefits produced by implementation of this controller over the current state of the art in ice bank load shifting control was tested in a day ahead real time electricity pricing forecast environment. This hypothetical real time electricity price was based on the cost of electricity in the Irish wholesale market. Multiple ice bank charge levels were simulated in order to quantify the performance of two control methods for varying operating conditions. First, the “standard controller” was based on the current modus operandi for ice bank systems where ice was generated for food cooling at night when the off-peak electricity tariff is available (00:00–08:00 h). Second, the “upgraded controller” was developed as a bespoke Demand Side Management control system for food refrigeration in a future electricity pricing environment. It consisted of a dual function load shifting optimisation algorithm, an ice bank model, and a predictive air temperature model. A preliminary study was also carried out to test the robustness of the controller’s performance in an uncertain real time electricity pricing forecast scenario. Both economic and grid management benefits were found by simulating the operation of the cold thermal storage load shifting controller in a

  2. Military Bases and Conservation Markets

    Energy Technology Data Exchange (ETDEWEB)

    Mark Ankeny

    2007-09-01

    Over time, DoD is likely to be one of the largest buyers and sellers in a water quality trading market. The Department of Defense (DoD) operates military bases that resemble small cities in infrastructure. As units redeploy, bases are likely to find themselves well within their environmental limits at the originating base and potentially bumping against limits such as nitrate and phosphate loading at the destination base. Stricter rules and heavier loadings in growing watersheds also present challenges to local bases and municipalities as regulators clamp down on loadings from existing Waste Water Treatment Plants (WWTPs) to meet water quality standards.

  3. Nanoparticle-based Sensors

    Directory of Open Access Journals (Sweden)

    V.K. Khanna

    2008-09-01

    Full Text Available Nanoparticles exhibit several unique properties that can be applied to develop chemical and biosensorspossessing desirable features like enhanced sensitivity and lower detection limits. Gold nanoparticles arecoated with sugars tailored to recognise different biological substances. When mixed with a weak solution ofthe sugar-coated nanoparticles, the target substance, e.g., ricin or E.coli, attaches to the sugar, thereby alteringits properties and changing the colour. Spores of bacterium labeled with carbon dots have been found to glowupon illumination when viewed with a confocal microscope. Enzyme/nanoparticle-based optical sensors forthe detection of organophosphate (OP compounds employ nanoparticle-modified fluorescence of an inhibitorof the enzyme to generate the signal for the OP compound detection. Nanoparticles shaped as nanoprisms,built of silver atoms, appear red on exposure to light. These nanoparticles are used as diagnostic labels thatglow when target DNA, e.g., those of anthrax or HIV, are present. Of great importance are tools like goldnanoparticle-enhanced surface-plasmon resonance sensor and silver nanoparticle surface-enhanced portableRaman integrated tunable sensor. Nanoparticle metal oxide chemiresistors using micro electro mechanical systemhotplate are very promising devices for toxic gas sensing. Chemiresistors comprising thin films of nanogoldparticles, encapsulated in monomolecular layers of functionalised alkanethiols, deposited on interdigitatedmicroelectrodes, show resistance changes through reversible absorption of vapours of harmful gases. Thispaper reviews the state-of-the-art sensors for chemical and biological terror agents, indicates their capabilitiesand applications, and presents the future scope of these devices.Defence Science Journal, 2008, 58(5, pp.608-616, DOI:http://dx.doi.org/10.14429/dsj.58.1683

  4. Lunar Base Heat Pump

    Science.gov (United States)

    Walker, D.; Fischbach, D.; Tetreault, R.

    1996-01-01

    The objective of this project was to investigate the feasibility of constructing a heat pump suitable for use as a heat rejection device in applications such as a lunar base. In this situation, direct heat rejection through the use of radiators is not possible at a temperature suitable for lde support systems. Initial analysis of a heat pump of this type called for a temperature lift of approximately 378 deg. K, which is considerably higher than is commonly called for in HVAC and refrigeration applications where heat pumps are most often employed. Also because of the variation of the rejection temperature (from 100 to 381 deg. K), extreme flexibility in the configuration and operation of the heat pump is required. A three-stage compression cycle using a refrigerant such as CFC-11 or HCFC-123 was formulated with operation possible with one, two or three stages of compression. Also, to meet the redundancy requirements, compression was divided up over multiple compressors in each stage. A control scheme was devised that allowed these multiple compressors to be operated as required so that the heat pump could perform with variable heat loads and rejection conditions. A prototype heat pump was designed and constructed to investigate the key elements of the high-lift heat pump concept. Control software was written and implemented in the prototype to allow fully automatic operation. The heat pump was capable of operation over a wide range of rejection temperatures and cooling loads, while maintaining cooling water temperature well within the required specification of 40 deg. C +/- 1.7 deg. C. This performance was verified through testing.

  5. Soy-based renoprotection.

    Science.gov (United States)

    McGraw, Nancy J; Krul, Elaine S; Grunz-Borgmann, Elizabeth; Parrish, Alan R

    2016-05-01

    Chronic kidney disease (CKD) is a significant public health problem as risk factors such as advanced age, obesity, hypertension and diabetes rise in the global population. Currently there are no effective pharmacologic treatments for this disease. The role of diet is important for slowing the progression of CKD and managing symptoms in later stages of renal insufficiency. While low protein diets are generally recommended, maintaining adequate levels of intake is critical for health. There is an increasing appreciation that the source of protein may also be important. Soybean protein has been the most extensively studied plant-based protein in subjects with kidney disease and has demonstrated renal protective properties in a number of clinical studies. Soy protein consumption has been shown to slow the decline in estimated glomerular filtration rate and significantly improve proteinuria in diabetic and non-diabetic patients with nephropathy. Soy's beneficial effects on renal function may also result from its impact on certain physiological risk factors for CKD such as dyslipidemia, hypertension and hyperglycemia. Soy intake is also associated with improvements in antioxidant status and systemic inflammation in early and late stage CKD patients. Studies conducted in animal models have helped to identify the underlying molecular mechanisms that may play a role in the positive effects of soy protein on renal parameters in polycystic kidney disease, metabolically-induced kidney dysfunction and age-associated progressive nephropathy. Despite the established relationship between soy and renoprotection, further studies are needed for a clear understanding of the role of the cellular and molecular target(s) of soy protein in maintaining renal function. PMID:27152261

  6. Telemetry-Based Ranging

    Science.gov (United States)

    Hamkins, Jon; Vilnrotter, Victor A.; Andrews, Kenneth S.; Shambayati, Shervin

    2011-01-01

    A telemetry-based ranging scheme was developed in which the downlink ranging signal is eliminated, and the range is computed directly from the downlink telemetry signal. This is the first Deep Space Network (DSN) ranging technology that does not require the spacecraft to transmit a separate ranging signal. By contrast, the evolutionary ranging techniques used over the years by NASA missions, including sequential ranging (transmission of a sequence of sinusoids) and PN-ranging (transmission of a pseudo-noise sequence) whether regenerative (spacecraft acquires, then regenerates and retransmits a noise-free ranging signal) or transparent (spacecraft feeds the noisy demodulated uplink ranging signal into the downlink phase modulator) relied on spacecraft power and bandwidth to transmit an explicit ranging signal. The state of the art in ranging is described in an emerging CCSDS (Consultative Committee for Space Data Systems) standard, in which a pseudo-noise (PN) sequence is transmitted from the ground to the spacecraft, acquired onboard, and the PN sequence is coherently retransmitted back to the ground, where a delay measurement is made between the uplink and downlink signals. In this work, the telemetry signal is aligned with the uplink PN code epoch. The ground station computes the delay between the uplink signal transmission and the received downlink telemetry. Such a computation is feasible because symbol synchronizability is already an integral part of the telemetry design. Under existing technology, the telemetry signal cannot be used for ranging because its arrival-time information is not coherent with any Earth reference signal. By introducing this coherence, and performing joint telemetry detection and arrival-time estimation on the ground, a high-rate telemetry signal can provide all the precision necessary for spacecraft ranging.

  7. Space-based detectors

    Science.gov (United States)

    Sesana, A.; Weber, W. J.; Killow, C. J.; Perreur-Lloyd, M.; Robertson, D. I.; Ward, H.; Fitzsimons, E. D.; Bryant, J.; Cruise, A. M.; Dixon, G.; Hoyland, D.; Smith, D.; Bogenstahl, J.; McNamara, P. W.; Gerndt, R.; Flatscher, R.; Hechenblaikner, G.; Hewitson, M.; Gerberding, O.; Barke, S.; Brause, N.; Bykov, I.; Danzmann, K.; Enggaard, A.; Gianolio, A.; Vendt Hansen, T.; Heinzel, G.; Hornstrup, A.; Jennrich, O.; Kullmann, J.; Møller-Pedersen, S.; Rasmussen, T.; Reiche, J.; Sodnik, Z.; Suess, M.; Armano, M.; Sumner, T.; Bender, P. L.; Akutsu, T.; Sathyaprakash, B. S.

    2014-12-01

    The parallel session C5 on Space-Based Detectors gave a broad overview over the planned space missions related to gravitational wave detection. Overviews of the revolutionary science to be expected from LISA was given by Alberto Sesana and Sasha Buchman. The launch of LISA Pathfinder (LPF) is planned for 2015. This mission and its payload "LISA Technology Package" will demonstrate key technologies for LISA. In this context, reference masses in free fall for LISA, and gravitational physics in general, was described by William Weber, laser interferometry at the pico-metre level and the optical bench of LPF was presented by Christian Killow and the performance of the LPF optical metrology system by Paul McNamara. While LPF will not yet be sensitive to gravitational waves, it may nevertheless be used to explore fundamental physics questions, which was discussed by Michele Armano. Some parts of the LISA technology that are not going to be demonstrated by LPF, but under intensive development at the moment, were presented by Oliver Jennrich and Oliver Gerberding. Looking into the future, Japan is studying the design of a mid-frequency detector called DECIGO, which was discussed by Tomotada Akutsu. Using atom interferometry for gravitational wave detection has also been recently proposed, and it was critically reviewed by Peter Bender. In the nearer future, the launch of GRACE Follow-On (for Earth gravity observation) is scheduled for 2017, and it will include a Laser Ranging Interferometer as technology demonstrator. This will be the first inter-spacecraft laser interferometer and has many aspects in common with the LISA long arm, as discussed by Andrew Sutton.

  8. From oil-based mud to water-based mud

    International Nuclear Information System (INIS)

    Maersk Olie og Gas AS has used low toxic oil-based muds extensively since 1982 for drilling development wells and later in the development of horizontal well drilling techniques. However, in view of the strong drive towards a reduction in the amount of oil discharged to the North Sea from the oil industry, Maersk Olie og Gas AS initiated trials with new or improved types of water-based mud, first in deviated wells (1989) and then in horizontal wells (1990). The paper reviews Maersk Olie og Gas As experience with oil-based mud since the drilling of the first horizontal well in 1987, specifically with respect to cuttings washing equipment, oil retention on cuttings, and the procedure for monitoring of this parameter. It describes the circumstances leading to the decision to revert to water-based mud systems. Finally, it reviews the experience gained so far with the new improved types of water-based mud systems, mainly glycol and KCl/polymer mud systems. Comparison of operational data, such as rate of penetration, torque and drag, etc., is made between wells drilled with oil-based mud and water-based mud. The trials with the new improved types of water-based mud systems have been positive, i.e. horizontal wells can be drilled successfully with water-based mud. As a result, Maersk Olie og and Gas AS has decided to discontinue the use of low toxic oil-based muds in the Danish sector of the North Sea

  9. Wind Energy Forecasting: A Collaboration of the National Center for Atmospheric Research (NCAR) and Xcel Energy

    Energy Technology Data Exchange (ETDEWEB)

    Parks, K.; Wan, Y. H.; Wiener, G.; Liu, Y.

    2011-10-01

    The focus of this report is the wind forecasting system developed during this contract period with results of performance through the end of 2010. The report is intentionally high-level, with technical details disseminated at various conferences and academic papers. At the end of 2010, Xcel Energy managed the output of 3372 megawatts of installed wind energy. The wind plants span three operating companies1, serving customers in eight states2, and three market structures3. The great majority of the wind energy is contracted through power purchase agreements (PPAs). The remainder is utility owned, Qualifying Facilities (QF), distributed resources (i.e., 'behind the meter'), or merchant entities within Xcel Energy's Balancing Authority footprints. Regardless of the contractual or ownership arrangements, the output of the wind energy is balanced by Xcel Energy's generation resources that include fossil, nuclear, and hydro based facilities that are owned or contracted via PPAs. These facilities are committed and dispatched or bid into day-ahead and real-time markets by Xcel Energy's Commercial Operations department. Wind energy complicates the short and long-term planning goals of least-cost, reliable operations. Due to the uncertainty of wind energy production, inherent suboptimal commitment and dispatch associated with imperfect wind forecasts drives up costs. For example, a gas combined cycle unit may be turned on, or committed, in anticipation of low winds. The reality is winds stayed high, forcing this unit and others to run, or be dispatched, to sub-optimal loading positions. In addition, commitment decisions are frequently irreversible due to minimum up and down time constraints. That is, a dispatcher lives with inefficient decisions made in prior periods. In general, uncertainty contributes to conservative operations - committing more units and keeping them on longer than may have been necessary for purposes of maintaining reliability

  10. Workplace Based Assessment in Psychiatry

    Directory of Open Access Journals (Sweden)

    Ayse Devrim Basterzi

    2009-11-01

    Full Text Available Workplace based assessment refers to the assessment of working practices based on what doctors actually do in the workplace, and is predominantly carried out in the workplace itself. Assessment drives learning and it is therefore essential that workplace-based assessment focuses on important attributes rather than what is easiest to assess. Workplacebased assessment is usually competency based. Workplace based assesments may well facilitate and enhance various aspects of educational supervisions, including its structure, frequency and duration etc. The structure and content of workplace based assesments should be monitored to ensure that its benefits are maximised by remaining tailored to individual trainees' needs. Workplace based assesment should be used for formative and summative assessments. Several formative assessment methods have been developed for use in the workplace such as mini clinical evaluation exercise (mini-cex, evidence based journal club assesment and case based discussion, multi source feedback etc. This review discusses the need of workplace based assesments in psychiatry graduate education and introduces some of the work place based assesment methods.

  11. Seguridad en bases de datos

    Directory of Open Access Journals (Sweden)

    Heidy Alina Nuevo León

    2011-11-01

    Full Text Available Los sistemas de base de datos son de gran uso, el cual va desde el uso de bases de datos ligeras, bases de datos en tiempo real (en algunas ocasiones obtenida a partir de la optimización de bases de datos relacionales y bases de datos relacionales con potentes gestores como aplicación proveedora del servicio. En el mundo del software libre existen gran cantidad de gestores de bases de datos, entre los que se encuentran mysql, berkeley db, sqlite y postgresql. Este último con gran número de seguidores y de personas de gran nivel en el mundo del desarrollo libre que contribuyen a su propósito.  El presente trabajo tiene como objetivo principal mostrar mediante una investigación los diferentes mecanismos para realizar la configuración de la seguridad para el gestor de base de datos Postgres

  12. Case-based reasoning: The marriage of knowledge base and data base

    Science.gov (United States)

    Pulaski, Kirt; Casadaban, Cyprian

    1988-01-01

    The coupling of data and knowledge has a synergistic effect when building an intelligent data base. The goal is to integrate the data and knowledge almost to the point of indistinguishability, permitting them to be used interchangeably. Examples given in this paper suggest that Case-Based Reasoning is a more integrated way to link data and knowledge than pure rule-based reasoning.

  13. Knowledge base verification based on enhanced colored petri net

    International Nuclear Information System (INIS)

    Verification is a process aimed at demonstrating whether a system meets it's specified requirements. As expert systems are used in various applications, the knowledge base verification of systems takes an importatn position. The conventional Petri net approach that has been studied recently in order to verify the knowledge base is found that it is inadequate to verify the knowledge base of large and complex system, such as alarm processing system of nuclear power plant. Thus, we propose an improved method that models the knowledge base as enhanced colored Petri net. In this study, we analyze the reachability and the error characteristics of the knowledge base and apply the method to verification of simple knowledge base

  14. Optimal pricing decision model based on activity-based costing

    Institute of Scientific and Technical Information of China (English)

    王福胜; 常庆芳

    2003-01-01

    In order to find out the applicability of the optimal pricing decision model based on conventional costbehavior model after activity-based costing has given strong shock to the conventional cost behavior model andits assumptions, detailed analyses have been made using the activity-based cost behavior and cost-volume-profitanalysis model, and it is concluded from these analyses that the theory behind the construction of optimal pri-cing decision model is still tenable under activity-based costing, but the conventional optimal pricing decisionmodel must be modified as appropriate to the activity-based costing based cost behavior model and cost-volume-profit analysis model, and an optimal pricing decision model is really a product pricing decision model construc-ted by following the economic principle of maximizing profit.

  15. Identity-based signature scheme based on quadratic residues

    Institute of Scientific and Technical Information of China (English)

    CHAI ZhenChuan; CAO ZhenFu; DONG XiaoLei

    2007-01-01

    Identity-based (ID-based) cryptography has drawn great concerns in recent years, and most of ID-based schemes are constructed from bilinear parings. Therefore, ID-based scheme without pairing is of great interest in the field of cryptography. Up to now,there still remains a challenge to construct ID-based signature scheme from quadratic residues. Thus, we aim to meet this challenge by proposing a concrete scheme. In this paper, we first introduce the technique of how to calculate a 2lth root of a quadratic residue, and then give a concrete ID-based signature scheme using such technique.We also prove that our scheme is chosen message and ID secure in the random oracle model, assuming the hardness of factoring.

  16. Knowledge base verification based on enhanced colored petri net

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jong Hyun; Seong, Poong Hyun [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of)

    1997-12-31

    Verification is a process aimed at demonstrating whether a system meets it`s specified requirements. As expert systems are used in various applications, the knowledge base verification of systems takes an important position. The conventional Petri net approach that has been studied recently in order to verify the knowledge base is found that it is inadequate to verify the knowledge base of large and complex system, such as alarm processing system of nuclear power plant. Thus, we propose an improved method that models the knowledge base as enhanced colored Petri net. In this study, we analyze the reachability and the error characteristics of the knowledge base and apply the method to verification of simple knowledge base. 8 refs., 4 figs. (Author)

  17. Evidence-based dentistry.

    Science.gov (United States)

    Chambers, David W

    2010-01-01

    Both panegyric and criticism of evidence-based dentistry tend to be clumsy because the concept is poorly defined. This analysis identifies several contributions to the profession that have been made under the EBD banner. Although the concept of clinicians integrating clinical epidemiology, the wisdom of their practices, and patients' values is powerful, its implementation has been distorted by a too heavy emphasis of computerized searches for research findings that meet the standards of academics. Although EBD advocates enjoy sharing anecdotal accounts of mistakes others have made, faulting others is not proof that one's own position is correct. There is no systematic, high-quality evidence that EBD is effective. The metaphor of a three-legged stool (evidence, experience, values, and integration) is used as an organizing principle. "Best evidence" has become a preoccupation among EBD enthusiasts. That overlong but thinly developed leg of the stool is critiqued from the perspectives of the criteria for evidence, the difference between internal and external validity, the relationship between evidence and decision making, the ambiguous meaning of "best," and the role of reasonable doubt. The strongest leg of the stool is clinical experience. Although bias exists in all observations (including searches for evidence), there are simple procedures that can be employed in practice to increase useful and objective evidence there, and there are dangers in delegating policy regarding allowable treatments to external groups. Patient and practitioner values are the shortest leg of the stool. As they are so little recognized, their integration in EBD is problematic and ethical tensions exist where paternalism privileges science over patient's self-determined best interests. Four potential approaches to integration are suggested, recognizing that there is virtually no literature on how the "seat" of the three-legged stool works or should work. It is likely that most dentists

  18. XML-Based SHINE Knowledge Base Interchange Language

    Science.gov (United States)

    James, Mark; Mackey, Ryan; Tikidjian, Raffi

    2008-01-01

    The SHINE Knowledge Base Interchange Language software has been designed to more efficiently send new knowledge bases to spacecraft that have been embedded with the Spacecraft Health Inference Engine (SHINE) tool. The intention of the behavioral model is to capture most of the information generally associated with a spacecraft functional model, while specifically addressing the needs of execution within SHINE and Livingstone. As such, it has some constructs that are based on one or the other.

  19. ANALYSIS-BASED SPARSE RECONSTRUCTION WITH SYNTHESIS-BASED SOLVERS

    OpenAIRE

    Cleju, Nicolae; Jafari, Maria,; Plumbley, Mark D.

    2012-01-01

    Analysis based reconstruction has recently been introduced as an alternative to the well-known synthesis sparsity model used in a variety of signal processing areas. In this paper we convert the analysis exact-sparse reconstruction problem to an equivalent synthesis recovery problem with a set of additional constraints. We are therefore able to use existing synthesis-based algorithms for analysis-based exact-sparse recovery. We call this the Analysis-By-Synthesis (ABS) approach. We evaluate o...

  20. Graph Cuts based Image Segmentation using Fuzzy Rule Based System

    OpenAIRE

    Khokher, M. R.; A. Ghafoor; A.M. Siddiqui

    2012-01-01

    This work deals with the segmentation of gray scale, color and texture images using graph cuts. From input image, a graph is constructed using intensity, color and texture profiles of the image simultaneously. Based on the nature of image, a fuzzy rule based system is designed to find the weight that should be given to a specific image feature during graph development. The graph obtained from the fuzzy rule based weighted average of different image features is further used in normalized graph...

  1. Game-based versus traditional case-based learning

    Science.gov (United States)

    Telner, Deanna; Bujas-Bobanovic, Maja; Chan, David; Chester, Bob; Marlow, Bernard; Meuser, James; Rothman, Arthur; Harvey, Bart

    2010-01-01

    ABSTRACT OBJECTIVE To evaluate family physicians’ enjoyment of and knowledge gained from game-based learning, compared with traditional case-based learning, in a continuing medical education (CME) event on stroke prevention and management. DESIGN An equivalence trial to determine if game-based learning was as effective as case-based learning in terms of attained knowledge levels. Game questions and small group cases were developed. Participants were randomized to either a game-based or a case-based group and took part in the event. SETTING Ontario provincial family medicine conference. PARTICIPANTS Thirty-two family physicians and 3 senior family medicine residents attending the conference. INTERVENTION Participation in either a game-based or a case-based CME learning group. MAIN OUTCOME MEASURES Scores on 40-item immediate and 3-month posttests of knowledge and a satisfaction survey. RESULTS Results from knowledge testing immediately after the event and 3 months later showed no significant difference in scoring between groups. Participants in the game-based group reported higher levels of satisfaction with the learning experience. CONCLUSION Games provide a novel way of organizing CME events. They might provide more group interaction and discussion, as well as improve recruitment to CME events. They might also provide a forum for interdisciplinary CME. Using games in future CME events appears to be a promising approach to facilitate participant learning. PMID:20841574

  2. Acids and bases solvent effects on acid-base strenght

    CERN Document Server

    Cox, Brian G

    2013-01-01

    Acids and bases are ubiquitous in chemistry. Our understanding of them, however, is dominated by their behaviour in water. Transfer to non-aqueous solvents leads to profound changes in acid-base strengths and to the rates and equilibria of many processes: for example, synthetic reactions involving acids, bases and nucleophiles; isolation of pharmaceutical actives through salt formation; formation of zwitter- ions in amino acids; and chromatographic separation of substrates. This book seeks to enhance our understanding of acids and bases by reviewing and analysing their behaviour in non-aqueous solvents. The behaviour is related where possible to that in water, but correlations and contrasts between solvents are also presented.

  3. Quantum Standard Teleportation Based on the Generic Measurement Bases

    Institute of Scientific and Technical Information of China (English)

    HAOSan-Ru; HOUBo-Yu; XIXiao-Qiang; YUERui-Hong

    2003-01-01

    We study the quantum standard teleportation based on the generic measurement bases. It is shown that the quantum standard teleportation does not depend on the explicit expression of the measurement bases. We have given the correspondence relation between the measurement performed by Alice and the unitary transformation performed by Bob. We also prove that the single particle unknown states and the two-particle unknown cat-like states can be exactly transmitted by means of the generic measurement bases and the correspondence unitary transformations.

  4. Computer-based and web-based radiation safety training

    Energy Technology Data Exchange (ETDEWEB)

    Owen, C., LLNL

    1998-03-01

    The traditional approach to delivering radiation safety training has been to provide a stand-up lecture of the topic, with the possible aid of video, and to repeat the same material periodically. New approaches to meeting training requirements are needed to address the advent of flexible work hours and telecommuting, and to better accommodate individuals learning at their own pace. Computer- based and web-based radiation safety training can provide this alternative. Computer-based and web- based training is an interactive form of learning that the student controls, resulting in enhanced and focused learning at a time most often chosen by the student.

  5. A New Approach to Optimal Allocation of Reactive Power Ancillary Service in Distribution Systems in the Presence of Distributed Energy Resources

    Directory of Open Access Journals (Sweden)

    Abouzar Samimi

    2015-11-01

    Full Text Available One of the most important Distribution System Operators (DSO schemes addresses the Volt/Var control (VVC problem. Developing a cost-based reactive power dispatch model for distribution systems, in which the reactive powers are appropriately priced, can motivate Distributed Energy Resources (DERs to participate actively in VVC. In this paper, new reactive power cost models for DERs, including synchronous machine-based DGs and wind turbines (WTs, are formulated based on their capability curves. To address VVC in the context of competitive electricity markets in distribution systems, first, in a day-ahead active power market, the initial active power dispatch of generation units is estimated considering environmental and economic aspects. Based on the results of the initial active power dispatch, the proposed VVC model is executed to optimally allocate reactive power support among all providers. Another novelty of this paper lies in the pricing scheme that rewards transformers and capacitors for tap and step changing, respectively, while incorporating the reactive power dispatch model. A Benders decomposition algorithm is employed as a solution method to solve the proposed reactive power dispatch, which is a mixed integer non-linear programming (MINLP problem. Finally, a typical 22-bus distribution network is used to verify the efficiency of the proposed method.

  6. Concurrent array-based queue

    Energy Technology Data Exchange (ETDEWEB)

    Heidelberger, Philip; Steinmacher-Burow, Burkhard

    2015-01-06

    According to one embodiment, a method for implementing an array-based queue in memory of a memory system that includes a controller includes configuring, in the memory, metadata of the array-based queue. The configuring comprises defining, in metadata, an array start location in the memory for the array-based queue, defining, in the metadata, an array size for the array-based queue, defining, in the metadata, a queue top for the array-based queue and defining, in the metadata, a queue bottom for the array-based queue. The method also includes the controller serving a request for an operation on the queue, the request providing the location in the memory of the metadata of the queue.

  7. Integration of Behind-the-Meter PV Fleet Forecasts into Utility Grid System Operations

    Energy Technology Data Exchange (ETDEWEB)

    Hoff, Thomas Hoff [Clean Power Research, L.L.C., Napa, CA (United States); Kankiewicz, Adam [Clean Power Research, L.L.C., Napa, CA (United States)

    2016-02-26

    Four major research objectives were completed over the course of this study. Three of the objectives were to evaluate three, new, state-of-the-art solar irradiance forecasting models. The fourth objective was to improve the California Independent System Operator’s (ISO) load forecasts by integrating behind-the-meter (BTM) PV forecasts. The three, new, state-of-the-art solar irradiance forecasting models included: the infrared (IR) satellite-based cloud motion vector (CMV) model; the WRF-SolarCA model and variants; and the Optimized Deep Machine Learning (ODML)-training model. The first two forecasting models targeted known weaknesses in current operational solar forecasts. They were benchmarked against existing operational numerical weather prediction (NWP) forecasts, visible satellite CMV forecasts, and measured PV plant power production. IR CMV, WRF-SolarCA, and ODML-training forecasting models all improved the forecast to a significant degree. Improvements varied depending on time of day, cloudiness index, and geographic location. The fourth objective was to demonstrate that the California ISO’s load forecasts could be improved by integrating BTM PV forecasts. This objective represented the project’s most exciting and applicable gains. Operational BTM forecasts consisting of 200,000+ individual rooftop PV forecasts were delivered into the California ISO’s real-time automated load forecasting (ALFS) environment. They were then evaluated side-by-side with operational load forecasts with no BTM-treatment. Overall, ALFS-BTM day-ahead (DA) forecasts performed better than baseline ALFS forecasts when compared to actual load data. Specifically, ALFS-BTM DA forecasts were observed to have the largest reduction of error during the afternoon on cloudy days. Shorter term 30 minute-ahead ALFS-BTM forecasts were shown to have less error under all sky conditions, especially during the morning time periods when traditional load forecasts often experience their largest

  8. Instantaneous noise-based logic

    OpenAIRE

    Kish, Laszlo B.; Khatri, Sunil; Peper, Ferdinand

    2010-01-01

    We show two universal, Boolean, deterministic logic schemes based on binary noise timefunctions that can be realized without time-averaging units. The first scheme is based on a new bipolar random telegraph wave scheme and the second one makes use of the recent noise-based logic which is conjectured to be the brain's method of logic operations [Physics Letters A 373 (2009) 2338-2342]. Error propagation and error removal issues are also addressed.

  9. Restructuring and simplifying rule bases

    OpenAIRE

    Vanthienen, Jan; Dries, E; WETS, G

    1995-01-01

    Rule bases are commonly acquired, by expert and/or knowledge engineer, in a form which is well suited for acquisition purposes. When the knowledge base is executed, however, a different structure may be required. Moreover, since human experts normally do not provide the knowledge in compact chunks, rule bases often suffer from redundancy. This may considerably harm efficiency. In this paper a procedure is examined to transform rules that are specified in the knowledge acquisition process ...

  10. Principles of models based engineering

    Energy Technology Data Exchange (ETDEWEB)

    Dolin, R.M.; Hefele, J.

    1996-11-01

    This report describes a Models Based Engineering (MBE) philosophy and implementation strategy that has been developed at Los Alamos National Laboratory`s Center for Advanced Engineering Technology. A major theme in this discussion is that models based engineering is an information management technology enabling the development of information driven engineering. Unlike other information management technologies, models based engineering encompasses the breadth of engineering information, from design intent through product definition to consumer application.

  11. dBASE IV basics

    Energy Technology Data Exchange (ETDEWEB)

    O`Connor, P.

    1994-09-01

    This is a user`s manual for dBASE IV. dBASE IV is a popular software application that can be used on your personal computer to help organize and maintain your database files. It is actually a set of tools with which you can create, organize, select and manipulate data in a simple yet effective manner. dBASE IV offers three methods of working with the product: (1) control center: (2) command line; and (3) programming.

  12. Trace-Based Code Generation for Model-Based Testing

    NARCIS (Netherlands)

    Kanstrén, T.; Piel, E.; Gross, H.-G.

    2009-01-01

    Paper Submitted for review at the Eighth International Conference on Generative Programming and Component Engineering. Model-based testing can be a powerful means to generate test cases for the system under test. However, creating a useful model for model-based testing requires expertise in the (fo

  13. Image based Monument Recognition using Graph based Visual Saliency

    DEFF Research Database (Denmark)

    Kalliatakis, Grigorios; Triantafyllidis, Georgios

    2013-01-01

    This article presents an image-based application aiming at simple image classification of well-known monuments in the area of Heraklion, Crete, Greece. This classification takes place by utilizing Graph Based Visual Saliency (GBVS) and employing Scale Invariant Feature Transform (SIFT) or Speeded...

  14. Distributed event-based systems

    CERN Document Server

    Fiege, Ludger; Pietzuch, Peter R

    2006-01-01

    This book provides an in-depth description of event-based systems, covering topics ranging from local event matching and distributed event forwarding algorithms, through a practical discussion of software engineering issues raised by the event-based style, to state-of-the-art research in event-based systems like composite event detection and security. The authors offer a comprehensive overview, and show the power of event-based architectures in modern system design, encouraging professionals to exploit this technique in next generation large-scale distributed applications like information diss

  15. Capability-based computer systems

    CERN Document Server

    Levy, Henry M

    2014-01-01

    Capability-Based Computer Systems focuses on computer programs and their capabilities. The text first elaborates capability- and object-based system concepts, including capability-based systems, object-based approach, and summary. The book then describes early descriptor architectures and explains the Burroughs B5000, Rice University Computer, and Basic Language Machine. The text also focuses on early capability architectures. Dennis and Van Horn's Supervisor; CAL-TSS System; MIT PDP-1 Timesharing System; and Chicago Magic Number Machine are discussed. The book then describes Plessey System 25

  16. Web-based support systems

    CERN Document Server

    Yao, JingTao

    2010-01-01

    The emerging interdisciplinary study of Web-based support systems focuses on the theories, technologies and tools for the design and implementation of Web-based systems that support various human activities. This book presents the state-of-the-art in Web-based support systems (WSS). The research on WSS is multidisciplinary and focuses on supporting various human activities in different domains/fields based on computer science, information technology, and Web technology. The main goal is to take the opportunities of the Web, to meet the challenges of the Web, to extend the human physical limita

  17. Developing and testing solar irradiance forecasting techniques in the Hawaiian Islands region

    Science.gov (United States)

    Matthews, D. K.

    2015-12-01

    The Hawaíi Natural Energy Institute (HNEI) is developing an operational solar forecasting for the Hawaiian Islands. The system comprises the following three components, covering forecasting horizons from seconds to days ahead. (i) A ground-observation driven advection model, using sky imagery and cloud height data. (ii) A satellite-image based advection model, primarily driven by Geostationary Operational Environmental Satellite (GOES) imagery. (iii) A coupled ocean-atmosphere model, using the Regional Ocean Modeling System (ROMS) model and the Weather Research and Forecasting (WRF) model, including newly available microphysics, shallow convection parameterization, and radiative transfer physics options. The satellite and NWP components provide coverage for the entire island chain, however, lack the resolution in time and space, to accurately forecast ramp events (large changes in irradiance that occur over a short period of time). Knowledge of the magnitude, duration and timing of ramp events are particularly important in Hawaíi due to the small size of the electric grids. Currently, HNEI employs a sky imager and ceilometer installed on the University of Hawaíi campus for high resolution forecasting, however, instrument design and cost limit widespread deployment. We discuss the development and preliminary validation of a new forecasting system based on inexpensive, panoramic (large FOV), off-the-shelf cameras with a cloud base height retrieval algorithm that does not require additional instrumentation.

  18. The Influence of Environmental Constraints on the Water Value

    Directory of Open Access Journals (Sweden)

    Ignacio Guisández

    2016-06-01

    Full Text Available The establishment of more severe hydrological environmental constraints, usually as seasonal minimum flows (ϕ and maximum ramping rates (ρ, on hydropower operation is a growing trend. This paper presents a study on the influence of ϕ and ρ on the water values (WV of a real hydropower plant that participates in the Spanish day-ahead electricity market. For this purpose, a master-slave algorithm, based on stochastic dynamic programming (SDP and deterministic mixed integer linear programming (DMILP, is used on a real hydropower plant. The master module, based on SDP, has a yearly planning period with weekly time steps and considers three state variables: stored water volume in the reservoir at the beginning of each week; weekly water inflow; and average weekly energy price. The slave module, based on DMILP, has a weekly planning period with hourly time steps and considers many features of the hydropower plant operation, such as: start-up costs, evaporation, wear and tear costs, etc. The results indicate that WV of a hydropower plant are very sensitive to the presence of these constraints; ϕ especially during the wettest season and ρ during the driest one. As the severity of ϕ and ρ increase, WV increase and decrease, respectively.

  19. Polyurethane Based Inhibition for High Flame Temperature Nitramine Based Composite Modified Double Base propellant

    OpenAIRE

    S. D. Kakade; M. V. Vaidya; D. G. Khangaonkar; P. K. Divekar; U. B. Kadam; S. N. Asthana

    1998-01-01

    The findings for polypropylene glycol (PPG) and hydroxyl-terminated polybutadiene (HTPB)-based inhibition systems are reported. These findings established that the inhibition system comprising HTPB-IPDI-IDP binder and Sb/sub 2/O/sub 3/-C black filler is most suitable for advanced nitramine-based composite modified double-base propellants in terms of mechanical properties and processibility. The promising composition was characterised for glass-transition behaviour and propellant-inhibi...

  20. Wavelength conversion based spectral imaging

    DEFF Research Database (Denmark)

    Dam, Jeppe Seidelin

    resolution for this spectral region. Today, an increasing number of applications exists outside the spectral region covered by Si-based devices, e.g. within cleantech, medical or food imaging. We present a technology based on wavelength conversion which will extend the spectral coverage of state of the art...

  1. Evidence-Based Laboratory Medicine

    Institute of Scientific and Technical Information of China (English)

    Christopher P Price

    2004-01-01

    @@ Whilst there have been several definitions of Evidence-Based Medicine (EBM), the one given by David Sackett is probably the most accurate and well accepted; he stated that "evidence-based medicine is the conscientious, explicit and judicious use of current best evidence in making decisions about the care of individual patients"[1].

  2. Theory-Based Stakeholder Evaluation

    Science.gov (United States)

    Hansen, Morten Balle; Vedung, Evert

    2010-01-01

    This article introduces a new approach to program theory evaluation called theory-based stakeholder evaluation or the TSE model for short. Most theory-based approaches are program theory driven and some are stakeholder oriented as well. Practically, all of the latter fuse the program perceptions of the various stakeholder groups into one unitary…

  3. Optical Fiber Grating based Sensors

    DEFF Research Database (Denmark)

    Michelsen, Susanne

    2003-01-01

    sampled gratings, was produced and investigated. It is based on the different temperature and strain response of these gratings. Both a transfer matrix method and an overlap calculation is performed to explain the sensor response. Another type of sensor is based on tuning and modulation of a laser...

  4. Knowledge-Based Asynchronous Programming

    NARCIS (Netherlands)

    Haan, Hendrik Wietze de; Hesselink, Wim H.; Renardel de Lavalette, Gerard R.

    2004-01-01

    A knowledge-based program is a high-level description of the behaviour of agents in terms of knowledge that an agent must have before (s)he may perform an action. The definition of the semantics of knowledge-based programs is problematic, since it involves a vicious circle; the knowledge of an agent

  5. Methods in Logic Based Control

    DEFF Research Database (Denmark)

    Christensen, Georg Kronborg

    1999-01-01

    Desing and theory of Logic Based Control systems.Boolean Algebra, Karnaugh Map, Quine McClusky's algorithm. Sequential control design. Logic Based Control Method, Cascade Control Method. Implementation techniques: relay, pneumatic, TTL/CMOS,PAL and PLC- and Soft_PLC implementation. PLC...

  6. Interpretation-Based Grammar Teaching.

    Science.gov (United States)

    Ellis, Rod

    1993-01-01

    In contrast to the usual approach to teaching grammar, this article argues for a comprehension-based approach. Based on a model of second-language acquisition, it examines a number of possible goals for grammar instruction (e.g., to promote "intake" of new grammatical features by helping learners notice input features and comprehend the meaning).…

  7. Team-Based Global Organizations

    DEFF Research Database (Denmark)

    Zander, Lena; Butler, Christina Lea; Mockaitis, Audra;

    2015-01-01

    the global firm. Practical implications-Practitioners can learn about organizational, team, and individual challenges and benefits of global team-based organizing. Originality/value-A century-old dominant organizational form is challenged when moving away from hierarchy-and hybrid-based forms of organizing...

  8. FAST WATERSHED-BASED DILATION

    OpenAIRE

    Jakub Smołka

    2014-01-01

    A watershed-based region growing image segmentation algorithm requires a fast watershed-based dilation implementation for effective operation. This paper presents a new way for watershed image representation and uses this representation for effective implementation of dilation. Methods for improving the algorithm speed are discussed. Presented solutions may also be used for solving other problems where fast set summation is required.

  9. Plasma-based accelerator structures

    Energy Technology Data Exchange (ETDEWEB)

    Schroeder, Carl B.

    1999-12-01

    Plasma-based accelerators have the ability to sustain extremely large accelerating gradients, with possible high-energy physics applications. This dissertation further develops the theory of plasma-based accelerators by addressing three topics: the performance of a hollow plasma channel as an accelerating structure, the generation of ultrashort electron bunches, and the propagation of laser pulses is underdense plasmas.

  10. Cloud-Based Data Storage

    Science.gov (United States)

    Waters, John K.

    2011-01-01

    The vulnerability and inefficiency of backing up data on-site is prompting school districts to switch to more secure, less troublesome cloud-based options. District auditors are pushing for a better way to back up their data than the on-site, tape-based system that had been used for years. About three years ago, Hendrick School District in…

  11. Plasma-based accelerator structures

    International Nuclear Information System (INIS)

    Plasma-based accelerators have the ability to sustain extremely large accelerating gradients, with possible high-energy physics applications. This dissertation further develops the theory of plasma-based accelerators by addressing three topics: the performance of a hollow plasma channel as an accelerating structure, the generation of ultrashort electron bunches, and the propagation of laser pulses is underdense plasmas

  12. GPP-Based Soft Base Station Designing and Optimization

    Institute of Scientific and Technical Information of China (English)

    Xiao-Feng Tao; Yan-Zhao Hou; Kai-Dong Wang; Hai-Yang He; Y.Jay Guo

    2013-01-01

    It is generally acknowledged that mobile communication base stations are composed of hardware components such as Field Programming Gate Array (FPGA),Digital Signal Processor (DSP),which promise reliable and fluent services for the mobile users.However,with the increasing demand for energy-efficiency,approaches of low power-consumption and high-flexibility are needed urgently.In this circumstance,General Purpose Processor (GPP) attracts people's attention for its low-cost and flexibility.Benefited from the development of modern GPP in multi-core,Single Instruction Multiple Data (SIMD) instructions,larger cache,etc.,GPPs are capable of performing high-density digital processing.In this paper,we compare several software-defined radio (SDR) prototypes and propose the general architecture of GPP-based soft base stations.Then,the schematic design of resource allocation and algorithm optimization in soft base station implementation are studied.As an application example,a prototype of GPP-based soft base station referring to the 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) is realized and evaluated.To the best of our knowledge,it is the first Soft-LTE prototype ever reported.In the end,we evaluate the timing performance of the LTE soft base station and a packet loss ratio of less than 0.003 is obtained.

  13. On the Impact of Caching and a Model for Storage-Capacity Measurements for Energy Conservation in Asymmetrical Wireless Devices

    CERN Document Server

    Mavromoustakis, Constandinos X

    2010-01-01

    Traffic and channel-data rate combined with the stream oriented methodology can provide a scheme for offering optimized and guaranteed QoS. In this work a stream oriented modeled scheme is proposed based on each node's self-scheduling energy management. This scheme is taking into account the overall packet loss in order to form the optimal effective -for the end-to-end connection- throughput response. The scheme also -quantitatively- takes into account the asymmetrical nature of wireless links and the caching activity that is used for data revocation in the ad-hoc based connectivity scenario. Through the designed middleware and the architectural layering and through experimental simulation, the proposed energy-aware management scheme is thoroughly evaluated in order to meet the parameters' values where the optimal throughput response for each device/user is achieved.

  14. Lignin-Based Thermoplastic Materials.

    Science.gov (United States)

    Wang, Chao; Kelley, Stephen S; Venditti, Richard A

    2016-04-21

    Lignin-based thermoplastic materials have attracted increasing interest as sustainable, cost-effective, and biodegradable alternatives for petroleum-based thermoplastics. As an amorphous thermoplastic material, lignin has a relatively high glass-transition temperature and also undergoes radical-induced self-condensation at high temperatures, which limits its thermal processability. Additionally, lignin-based materials are usually brittle and exhibit poor mechanical properties. To improve the thermoplasticity and mechanical properties of technical lignin, polymers or plasticizers are usually integrated with lignin by blending or chemical modification. This Review attempts to cover the reported approaches towards the development of lignin-based thermoplastic materials on the basis of published information. Approaches reviewed include plasticization, blending with miscible polymers, and chemical modifications by esterification, etherification, polymer grafting, and copolymerization. Those lignin-based thermoplastic materials are expected to show applications as engineering plastics, polymeric foams, thermoplastic elastomers, and carbon-fiber precursors. PMID:27059111

  15. Lignin-Based Thermoplastic Materials.

    Science.gov (United States)

    Wang, Chao; Kelley, Stephen S; Venditti, Richard A

    2016-04-21

    Lignin-based thermoplastic materials have attracted increasing interest as sustainable, cost-effective, and biodegradable alternatives for petroleum-based thermoplastics. As an amorphous thermoplastic material, lignin has a relatively high glass-transition temperature and also undergoes radical-induced self-condensation at high temperatures, which limits its thermal processability. Additionally, lignin-based materials are usually brittle and exhibit poor mechanical properties. To improve the thermoplasticity and mechanical properties of technical lignin, polymers or plasticizers are usually integrated with lignin by blending or chemical modification. This Review attempts to cover the reported approaches towards the development of lignin-based thermoplastic materials on the basis of published information. Approaches reviewed include plasticization, blending with miscible polymers, and chemical modifications by esterification, etherification, polymer grafting, and copolymerization. Those lignin-based thermoplastic materials are expected to show applications as engineering plastics, polymeric foams, thermoplastic elastomers, and carbon-fiber precursors.

  16. Tag Based Audio Search Engine

    Directory of Open Access Journals (Sweden)

    Parameswaran Vellachu

    2012-03-01

    Full Text Available The volume of the music database is increasing day by day. Getting the required song as per the choice of the listener is a big challenge. Hence, it is really hard to manage this huge quantity, in terms of searching, filtering, through the music database. It is surprising to see that the audio and music industry still rely on very simplistic metadata to describe music files. However, while searching audio resource, an efficient "Tag Based Audio Search Engine" is necessary. The current research focuses on two aspects of the musical databases 1. Tag Based Semantic Annotation Generation using the tag based approach.2. An audio search engine, using which the user can retrieve the songs based on the users choice. The proposed method can be used to annotation and retrieve songs based on musical instruments used , mood of the song, theme of the song, singer, music director, artist, film director, instrument, genre or style and so on.

  17. Comparative Study of Triangulation based and Feature based Image Morphing

    Directory of Open Access Journals (Sweden)

    Ms. Bhumika G. Bhatt

    2012-01-01

    Full Text Available Image Morphing is one of the most powerful Digital Image processing technique, which is used to enhancemany multimedia projects, presentations, education and computer based training. It is also used inmedical imaging field to recover features not visible in images by establishing correspondence of featuresamong successive pair of scanned images. This paper discuss what morphing is and implementation ofTriangulation based morphing Technique and Feature based Image Morphing. IT analyze both morphingtechniques in terms of different attributes such as computational complexity, Visual quality of morphobtained and complexity involved in selection of features.

  18. Survey paper on Sketch Based and Content Based Image Retrieval

    OpenAIRE

    Gaidhani, Prachi A.; S. B. Bagal

    2015-01-01

    This survey paper presents an overview of development of Sketch Based Image Retrieval (SBIR) and Content based image retrieval (CBIR) in the past few years. There is awful growth in bulk of images as well as the far-flung application in too many fields. The main attributes to represent as well index the images are color, shape, texture, spatial layout. These features of images are extracted to check similarity among the images. Generation of special query is the main problem of content based ...

  19. Content-Based Image Retrial Based on Hadoop

    Directory of Open Access Journals (Sweden)

    DongSheng Yin

    2013-01-01

    Full Text Available Generally, time complexity of algorithms for content-based image retrial is extremely high. In order to retrieve images on large-scale databases efficiently, a new way for retrieving based on Hadoop distributed framework is proposed. Firstly, a database of images features is built by using Speeded Up Robust Features algorithm and Locality-Sensitive Hashing and then perform the search on Hadoop platform in a parallel way specially designed. Considerable experimental results show that it is able to retrieve images based on content on large-scale cluster and image sets effectively.

  20. 基于WCVaR风险度量的发电商电量分配模型%Optimization Portfolio Allocation for Generation Companies Based on Worst-case Conditional Value-at-risk

    Institute of Scientific and Technical Information of China (English)

    周娟; 江辉; 李鹏

    2012-01-01

    电力市场中,发电商需要合理分配发电量以追求总利润最大、风险最小.以最坏情况风险价值(WCVaR)作为风险度量因子,建立了发电商在保证一定的期望收益率下WCVaR风险值最小的发电量分配模型,并对其在实时平衡市场、日前市场和中、远期合约市场的发电量分配比例及有效前沿进行了仿真测验.结果表明,所提出的电量分配模型能较真实地反映发电商所面临的市场风险的本质特性,表明了理论分析的正确性和模型的有效性,从而为发电商的投标决策和风险评估提供了新思路.%To obtain the maximal profit and the minimum risk, it is the duty of generation companies to allocate energy reasonably in power market. Taking the WCVaR as risk management index, an optimal energy allocation model was built for generation companies. Plentiful cases were simulated to test the efficient frontier of models and the energy asset allocation ratio for generation companies among real time equilibrium market, day ahead market, middle-term and long-term contract market. The simulation result shows that the proposed model can exactly reflect the essential characteristics of the market risks which the generation companies must face, the theoretical analysis is correct and the new models are valid. Thereby, the proposed model can be applied to purchasing strategies and risk evaluation of generation companies.

  1. Efficient determination of distribution tariffs for the prevention of congestion from EV Charging

    DEFF Research Database (Denmark)

    O'Connell, Niamh; Wu, Qiuwei; Østergaard, Jacob

    2012-01-01

    into the day-ahead market. The DT acts to disperse charging at congested periods and locations, thereby preventing congestion on a day-ahead basis. The magnitude of the DT is determined from a simulated locational marginal prices (LMPs), and the time extent of the DT is determined from analysis of the system...... is highly efficient at grid congestion prevention, and the precise level of congestion that can be alleviated is dependent on the price profile of the optimisation period in question.......A dual objective electric vehicle (EV) charging schedule optimisation is proposed here whereby both consumer driving requirements and grid constraints are respected. A day-ahead dynamic tariff (DT) for distribution systems is proposed as a price signal to EV fleet operators (FO) bidding...

  2. Value-based metrics and Internet-based enterprises

    Science.gov (United States)

    Gupta, Krishan M.

    2001-10-01

    Within the last few years, a host of value-based metrics like EVA, MVA, TBR, CFORI, and TSR have evolved. This paper attempts to analyze the validity and applicability of EVA and Balanced Scorecard for Internet based organizations. Despite the collapse of the dot-com model, the firms engaged in e- commerce continue to struggle to find new ways to account for customer-base, technology, employees, knowledge, etc, as part of the value of the firm. While some metrics, like the Balance Scorecard are geared towards internal use, others like EVA are for external use. Value-based metrics are used for performing internal audits as well as comparing firms against one another; and can also be effectively utilized by individuals outside the firm looking to determine if the firm is creating value for its stakeholders.

  3. G -Frames, g -orthonormal bases and g -Riesz bases

    Directory of Open Access Journals (Sweden)

    Seyedeh Sara Karimizad

    2014-05-01

    Full Text Available G-Frames in Hilbert spaces are a redundant set of operators which yield a repre-sentation for each vector in the space. In this paper we investigate the connection betweeng-frames, g-orthonormal bases and g-Riesz bases. We show that a family of bounded opera-tors is a g-Bessel sequences if and only if the Gram matrix associated to its denes a bounded operator

  4. Content-Based Image Retrial Based on Hadoop

    OpenAIRE

    DongSheng Yin; DeBo Liu

    2013-01-01

    Generally, time complexity of algorithms for content-based image retrial is extremely high. In order to retrieve images on large-scale databases efficiently, a new way for retrieving based on Hadoop distributed framework is proposed. Firstly, a database of images features is built by using Speeded Up Robust Features algorithm and Locality-Sensitive Hashing and then perform the search on Hadoop platform in a parallel way specially designed. Considerable experimental results show that it is abl...

  5. Implementation of activity based cost management aboard base installations

    OpenAIRE

    Stanley, James; Perkins, Nicholas R.; Zander, Laura

    2004-01-01

    Approved for public release; distribution is unlimited. MBA Professional Report This project is a comparative analysis of the implementation process of Activity Based Cost Management of Marine Corps Logistics Base, (MCLB), Albany, and the implementation procedures used aboard MCB Camp Lejeune. Interviews and data gathering were conducted to identify how the respective Business Performance Offices (BPO), plan, implement, monitor, and measure performance of their process to introduce ABCM...

  6. Trace-Based Code Generation for Model-Based Testing

    OpenAIRE

    Kanstrén, T.; Piel, E.; Gross, H.-G.

    2009-01-01

    Paper Submitted for review at the Eighth International Conference on Generative Programming and Component Engineering. Model-based testing can be a powerful means to generate test cases for the system under test. However, creating a useful model for model-based testing requires expertise in the (formal) modeling language of the used tool and the general concept of modeling the system under test for effective test generation. A commonly used modeling notation is to describe the model through a...

  7. On Knowledge Excavation Based on University Library Knowledge Base

    OpenAIRE

    Ying Song

    2009-01-01

    Knowledge excavation is a new information processing technology. Nowadays, knowledge excavation has been widely applied to the university library management. Knowledge excavation in university library knowledge bases has already been playing an important role in improving the management of university libraries and inevitably will play a more profound role in the future. In this paper, the meaning of knowledge excavation in university library knowledge bases and other related issues are studie...

  8. Problem-based, interdisciplinary field-based courses

    DEFF Research Database (Denmark)

    Hill, Trevor; Birch-Thomsen, Torben; Traynor, Catherine;

    2008-01-01

    Student field courses at Universities are increasingly incorporating problem-based interdisciplinary approaches to enhance learning opportunities. This paper reports upon seven field-based, problem-oriented, interdisciplinary courses held within southern Africa concerning natural resource...... in a positive manner and a strong respectful working relationship from the staff. We advocate this process as worthwhile as classroom theory becomes real in all applied and complex environment....

  9. Region-based multimodal image fusion using ICA bases

    OpenAIRE

    Cvejic, N; Lewis, J.; Bull, DR; Canagarajah, CN

    2006-01-01

    In this paper, we present a novel region-based multimodal image fusion algorithm in the ICA domain. It uses segmentation to determine the most important regions in the input images and consequently fuses the ICA coefficients from the given regions. The proposed method exhibits considerably higher performance than the basic ICA algorithm and shows improvement over other state-of-the-art algorithms In this paper, we present a novel region-based multimodal image fusion algorithm in the ICA do...

  10. Object-Based Benefits without Object-Based Representations

    OpenAIRE

    Alvarez, George Angelo; Fougnie, Daryl; Cormiea, Sarah M

    2012-01-01

    The organization of visual information into objects strongly influences visual memory: Displays with objects defined by two features (e.g. color, orientation) are easier to remember than displays with twice as many objects defined by one feature (Olson & Jiang, 2002). Existing theories suggest that this ‘object-benefit’ is based on object-based limitations in working memory: because a limited number of objects can be stored, packaging features together so that fewer objects have to be remembe...

  11. Mineral-resource data bases

    Science.gov (United States)

    ,

    1997-01-01

    Data bases are essential for modern scientific research. The new and exciting work being done in the Mineral Resource Program in the U.S. Geological Survey (USGS) usually begins with the question, "Where are the known deposits?" A mineral-resource data base containing this type of information and more can be useful not just to USGS scientists, but to anyone who needs such data. Users of the data bases from outside the USGS include mining and exploration companies, environmental groups, academia, other Federal Agencies, and the general public. At present, the USGS has two large mineral-resource data bases, MRDS (Mineral Resource Data System) and MAS (Minerals Availability System). MRDS was built and is mamtained by the USGS, and MAS was built and maintained by the Bureau of Mines. In 1996, after the Bureau was abolished, MAS was transferred to the USGS. The two data bases were compiled for different purposes and contain very different mformation. For instance, MAS contains information on costs, details of mining methods, and feasibility studies. MRDS has mineralogical and geologic data that are not contained in MAS. Because they are both mineral-resource data bases, however, they contain some information in common, such as location, name(s) of sites, and commodities present. Both data bases are international in scope, and both are quite large. MRDS contains over 110,000 records, while MAS has over 220,000. One reason that MAS has more records is that it contains information on smelters, mill sites, and fossil fuel sites, as well as mineral- resource sites. The USGS is working to combine the information in both data bases. This is a large undertaking that will require some years to complete. In the interim, information from both data bases will still be available

  12. Home-based Healthcare Technology

    DEFF Research Database (Denmark)

    Verdezoto, Nervo

    Sustaining daily, unsupervised healthcare activities in non-clinical settings such as the private home can challenge, among others, older adults. To support such unsupervised care activities, an increasingly number of reminders and monitoring systems are being designed. However, most...... of these systems target a specific treatment or condition and might not be sufficient to support the care management work at home. Based on a case study approach, my research investigates home-based healthcare practices and how they can inform future design of home-based healthcare technology that better account...... for the home setting and people’s everyday activities....

  13. Office-based laryngeal injections.

    Science.gov (United States)

    Mallur, Pavan S; Rosen, Clark A

    2013-02-01

    Office-based vocal fold injection (VFI), though initially described more than a century ago, has recently reemerged as an attractive alternative to VFI performed during microsuspension laryngoscopy. Multiple office-based approaches exist, including percutaneous, peroral, and transnasal endoscopic approaches. Surgeon preference typically dictates the approach, although patient tolerance or anatomic variations are also key factors. Regardless of the approach or indication, a myriad of technical considerations make preparation and familiarity requisite for optimal patient outcomes. Office-based VFI offers several distinct advantages over traditional direct or microsuspension laryngoscopy VFI, making it a standard of treatment for a variety of indications. PMID:23177408

  14. Graph Model Based Indoor Tracking

    DEFF Research Database (Denmark)

    Jensen, Christian Søndergaard; Lu, Hua; Yang, Bin

    2009-01-01

    infrastructure for different symbolic positioning technologies, e.g., Bluetooth and RFID. More specifically, the paper proposes a model of indoor space that comprises a base graph and mappings that represent the topology of indoor space at different levels. The resulting model can be used for one or several...... indoor positioning technologies. Focusing on RFID-based positioning, an RFID specific reader deployment graph model is built from the base graph model. This model is then used in several algorithms for constructing and refining trajectories from raw RFID readings. Empirical studies with implementations...

  15. Formal Component-Based Semantics

    CERN Document Server

    Madlener, Ken; van Eekelen, Marko; 10.4204/EPTCS.62.2

    2011-01-01

    One of the proposed solutions for improving the scalability of semantics of programming languages is Component-Based Semantics, introduced by Peter D. Mosses. It is expected that this framework can also be used effectively for modular meta theoretic reasoning. This paper presents a formalization of Component-Based Semantics in the theorem prover Coq. It is based on Modular SOS, a variant of SOS, and makes essential use of dependent types, while profiting from type classes. This formalization constitutes a contribution towards modular meta theoretic formalizations in theorem provers. As a small example, a modular proof of determinism of a mini-language is developed.

  16. PBW bases and KLR algebras

    OpenAIRE

    Kato, Syu

    2012-01-01

    We generalize Lusztig's geometric construction of the PBW bases of finite quantum groups of type $\\mathsf{ADE}$ under the framework of [Varagnolo-Vasserot, J. reine angew. Math. 659 (2011)]. In particular, every PBW basis of such quantum groups is proven to yield a semi-orthogonal collection in the module category of the KLR-algebras. This enables us to prove Lusztig's conjecture on the positivity of the canonical (lower global) bases in terms of the (lower) PBW bases in the $\\mathsf{ADE}$ ca...

  17. Export base of czech regions

    OpenAIRE

    Michal Šulc

    2010-01-01

    This article deals with the analysis of structure and size of goods exported from the Czech regions in the period of 2003–2009. The analysis is related to the export base theory. At first there is the export base theory characterised in the beginning of the article. There is a limited data base for the assessing of international flow of goods and services in case of Czech regions, for only the data of exported goods is regionally monitored. Both the presence and the increase of importance of ...

  18. Solar based hydrogen production systems

    CERN Document Server

    Dincer, Ibrahim

    2013-01-01

    This book provides a comprehensive analysis of various solar based hydrogen production systems. The book covers first-law (energy based) and second-law (exergy based) efficiencies and provides a comprehensive understanding of their implications. It will help minimize the widespread misuse of efficiencies among students and researchers in energy field by using an intuitive and unified approach for defining efficiencies. The book gives a clear understanding of the sustainability and environmental impact analysis of the above systems. The book will be particularly useful for a clear understanding

  19. Seeing graphene-based sheets

    Directory of Open Access Journals (Sweden)

    Jaemyung Kim

    2010-03-01

    Full Text Available Graphene-based sheets such as graphene, graphene oxide and reduced graphene oxide have stimulated great interest due to their promising electronic, mechanical and thermal properties. Microscopy imaging is indispensable for characterizing these single atomic layers, and oftentimes is the first measure of sample quality. This review provides an overview of current imaging techniques for graphene-based sheets and highlights a recently developed fluorescence quenching microscopy technique that allows high-throughput, high-contrast imaging of graphene-based sheets on arbitrary substrate and even in solution.

  20. Flow tracing based on current

    Institute of Scientific and Technical Information of China (English)

    蔡兴国; 曹海龙

    2001-01-01

    Analyses the flow tracing based on power flow, points out that the detachment of reactive power and active power is unrealiable and concludes that the current is the real basic of flow tracing,and proposes the new flow tracing model based on current, which devides the current into active current and reactive current, analyses the theory about the matrix to deal with the precision and realization of the flow tracing, and then proposes a new pricing model by fixed rate and marginal rate, which keeps not only economy information such as congestion cost in marginal cost based pricing, but also benefits to make both ends meet.

  1. A stochastic security approach to energy and spinning reserve scheduling considering demand response program

    International Nuclear Information System (INIS)

    In this paper a new algorithm for allocating energy and determining the optimum amount of network active power reserve capacity and the share of generating units and demand side contribution in providing reserve capacity requirements for day-ahead market is presented. In the proposed method, the optimum amount of reserve requirement is determined based on network security set by operator. In this regard, Expected Load Not Supplied (ELNS) is used to evaluate system security in each hour. The proposed method has been implemented over the IEEE 24-bus test system and the results are compared with a deterministic security approach, which considers certain and fixed amount of reserve capacity in each hour. This comparison is done from economic and technical points of view. The promising results show the effectiveness of the proposed model which is formulated as mixed integer linear programming (MILP) and solved by GAMS software. -- Highlights: → Determination of optimal spinning reserve capacity requirement in order to satisfy desired security level set by system operator based on stochastic approach. → Scheduling energy and spinning reserve markets simultaneously. → Comparing the stochastic approach with deterministic approach to determine the advantages and disadvantages of each. → Examine the effect of demand response participation in reserve market to provide spinning reserve.

  2. Forecasting Model for Crude Oil Price Using Artificial Neural Networks and Commodity Futures Prices

    CERN Document Server

    Kulkarni, Siddhivinayak

    2009-01-01

    This paper presents a model based on multilayer feedforward neural network to forecast crude oil spot price direction in the short-term, up to three days ahead. A great deal of attention was paid on finding the optimal ANN model structure. In addition, several methods of data pre-processing were tested. Our approach is to create a benchmark based on lagged value of pre-processed spot price, then add pre-processed futures prices for 1, 2, 3,and four months to maturity, one by one and also altogether. The results on the benchmark suggest that a dynamic model of 13 lags is the optimal to forecast spot price direction for the short-term. Further, the forecast accuracy of the direction of the market was 78%, 66%, and 53% for one, two, and three days in future conclusively. For all the experiments, that include futures data as an input, the results show that on the short-term, futures prices do hold new information on the spot price direction. The results obtained will generate comprehensive understanding of the cr...

  3. Strategic bidding for wind power producers in electricity markets

    International Nuclear Information System (INIS)

    Highlights: • Game theoretic bidding strategy approach developed to optimize wind power producers bids. • Rival behavior modeled through Stochastic Cournot model. • Location based dual imbalance price mechanism proposed to obtain imbalance charges. • Proposed approach evaluated using two realistic case studies. • Proposed approach increases profit of strategic wind power producers significantly. - Abstract: In evolving electricity markets, wind power producers (WPPs) would increase their profit through strategic bidding. However, generated power by WPPs is highly random, which may result into heavy imbalance charges. In markets dominated by wind generators, they would optimize their offered bids, considering rival behavior. In oligopolistic day-ahead electricity markets, this strategic behavior can be represented as a Stochastic Cournot model. Wind uncertainty is represented by scenarios generated using Auto Regressive Moving Average (ARMA) model. With a consideration of wind power uncertainty and imbalance charges, strategic WPPs can maximize their expected payoff or profit through the proposed Nash equilibrium based bidding strategy. Nash equilibrium is obtained using payoff matrix approach. Proposed approach is evaluated on two realistic case studies considering different technical constraints. Obtained results shows that proposed bidding strategy mechanism offers quantum increase in profit for WPPs, when their behavior is modeled in a game theoretic framework. Flexibility of approach offers opportunities for its extension to associated challenges

  4. A New Two-Stage Approach to Short Term Electrical Load Forecasting

    Directory of Open Access Journals (Sweden)

    Dragan Tasić

    2013-04-01

    Full Text Available In the deregulated energy market, the accuracy of load forecasting has a significant effect on the planning and operational decision making of utility companies. Electric load is a random non-stationary process influenced by a number of factors which make it difficult to model. To achieve better forecasting accuracy, a wide variety of models have been proposed. These models are based on different mathematical methods and offer different features. This paper presents a new two-stage approach for short-term electrical load forecasting based on least-squares support vector machines. With the aim of improving forecasting accuracy, one more feature was added to the model feature set, the next day average load demand. As this feature is unknown for one day ahead, in the first stage, forecasting of the next day average load demand is done and then used in the model in the second stage for next day hourly load forecasting. The effectiveness of the presented model is shown on the real data of the ISO New England electricity market. The obtained results confirm the validity advantage of the proposed approach.

  5. Hybrid biomass-wind power plant for reliable energy generation

    International Nuclear Information System (INIS)

    Massive implementation of renewable energy resources is a key element to reduce CO2 emissions associated to electricity generation. Wind resources can provide an important alternative to conventional electricity generation mainly based on fossil fuels. However, wind generators are greatly affected by the restrictive operating rules of electricity markets because, as wind is naturally variable, wind generators may have serious difficulties on submitting accurate generation schedules on a day ahead basis, and on complying with scheduled obligations in real-time operation. In this paper, an innovative system combining a biomass gasification power plant, a gas storage system and stand-by generators to stabilize a generic 40 MW wind park is proposed and evaluated with real data. The wind park power production model is based on real data about power production of a Spanish wind park and a probabilistic approach to quantify fluctuations and so, power compensation needs. The hybrid wind-biomass system is analysed to obtain main hybrid system design parameters. This hybrid system can mitigate wind prediction errors and so provide a predictable source of electricity. An entire year cycle of hourly power compensations needs has been simulated deducing storage capacity, extra power needs of the biomass power plant and stand-by generation capacity to assure power compensation during critical peak hours with acceptable reliability. (author)

  6. A Sequential Monte Carlo Approach for Streamflow Forecasting

    Science.gov (United States)

    Hsu, K.; Sorooshian, S.

    2008-12-01

    As alternatives to traditional physically-based models, Artificial Neural Network (ANN) models offer some advantages with respect to the flexibility of not requiring the precise quantitative mechanism of the process and the ability to train themselves from the data directly. In this study, an ANN model was used to generate one-day-ahead streamflow forecasts from the precipitation input over a catchment. Meanwhile, the ANN model parameters were trained using a Sequential Monte Carlo (SMC) approach, namely Regularized Particle Filter (RPF). The SMC approaches are known for their capabilities in tracking the states and parameters of a nonlinear dynamic process based on the Baye's rule and the proposed effective sampling and resampling strategies. In this study, five years of daily rainfall and streamflow measurement were used for model training. Variable sample sizes of RPF, from 200 to 2000, were tested. The results show that, after 1000 RPF samples, the simulation statistics, in terms of correlation coefficient, root mean square error, and bias, were stabilized. It is also shown that the forecasted daily flows fit the observations very well, with the correlation coefficient of higher than 0.95. The results of RPF simulations were also compared with those from the popular back-propagation ANN training approach. The pros and cons of using SMC approach and the traditional back-propagation approach will be discussed.

  7. Consumption-based Equity Valuation

    DEFF Research Database (Denmark)

    Bach, Christian; Christensen, Peter Ove

    2013-01-01

    model performs substantially better than the best performing standard valuation model when comparing absolute valuation errors. Both types of models are able to identify investment strategies with subsequent excess returns but also in this setting, the CCAPM-based valuation model outperforms...... residual income for risk in the numerator rather than through a risk-adjusted cost of equity in the denominator. The risk-adjustments are derived based on assumptions about the time-series properties of residual income returns and aggregate consumption rather than on historical stock returns. We compare...... the performance of the model with several implementations of standard valuation models, both in terms of absolute valuation errors, and in terms of the returns on simple investment strategies based on the differences between model and market prices in the respective valuation models. The CCAPM-based valuation...

  8. Team-based global organizations

    DEFF Research Database (Denmark)

    Zander, Lena; Butler, Christina; Mockaitis, Audra;

    2015-01-01

    characterized by decreased importance of hierarchal structures, more fluidity across borders, even a possible dissolution of firm boundaries, we move towards team-based organizing as an alternative to more traditional forms of hierarchical-based organizing in global firms. To provide input for a discussion...... of challenges and opportunities of future global organizing as being team-based, we presented new advancements in the study of global teams, leadership, process and outcomes divided into four themes. Two specifically address processes in global teams: 1) the benefits of openness towards linguistic and value...... diversity in enhancing team creativity and performance, and 2) the sharing of knowledge in team-based organizations, while the other two themes address global team leadership: 3) the unprecedented significance of social capital for the success of global team leader roles; and 4) the link between shared...

  9. FEMA DFIRM Base Flood Elevations

    Data.gov (United States)

    Minnesota Department of Natural Resources — The Base Flood Elevation (BFE) table is required for any digital data where BFE lines will be shown on the corresponding Flood Insurance Rate Map (FIRM). Normally,...

  10. Mindfulness-Based Stress Reduction

    Science.gov (United States)

    ... R S T U V W X Y Z Mindfulness-Based Stress Reduction (MBSR) Information 5 Things You ... Better Than Usual Care Alone (03/22/16) Mindfulness Meditation May Benefit People With Chronic Insomnia (09/ ...

  11. Industry Based Survey (IBS) Cod

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The "Gulf of Maine Atlantic Cod Industry-Based Survey" was a collaboration of the Massachusetts Division of Marine Fisheries and the fishing industry, with support...

  12. Studying Sensing-Based Systems

    DEFF Research Database (Denmark)

    Kjærgaard, Mikkel Baun

    2013-01-01

    Recent sensing-based systems involve a multitude of users, devices, and places. These types of systems challenge existing approaches for conducting valid system evaluations. Here, the author discusses such evaluation challenges and revisits existing system evaluation methodologies....

  13. Base Flood Elevation (BFE) Lines

    Data.gov (United States)

    Department of Homeland Security — The Base Flood Elevation (BFE) table is required for any digital data where BFE lines will be shown on the corresponding Flood Insurance Rate Map (FIRM). Normally...

  14. The Knowledge Based Information Economy

    OpenAIRE

    Eliasson, Gunnar; Fölster, Stefan; Lindberg, Thomas; Pousette, Tomas; Erol TAYMAZ

    1990-01-01

    Working Paper No. 256 is published as "The Knowledge Based Information Economy" (authors: Gunnar Eliasson, Stefan Fölster, Thomas Lindberg, Tomas Pousette and Erol Taymaz). Stockholm: Industrial Institute for Economic and Social Research and Telecon, 1990.

  15. Base Flow Model Validation Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The program focuses on turbulence modeling enhancements for predicting high-speed rocket base flows. A key component of the effort is the collection of...

  16. Evidence-based playground design

    DEFF Research Database (Denmark)

    Refshauge, Anne Dahl; Stigsdotter, Ulrika K.; Lamm, Bettina;

    2015-01-01

    This paper develops, explores and evaluates an evidence-based approach to playground design, with a public park playground (playlab Cph) in Copenhagen as a case study. In the increasingly urbanised world, park playgrounds are valuable places that support healthy child development by providing...... opportunities for play, nature exploration and sensory stimulation. As it is increasingly expected that designers base their decisions on research evidence, there is a need to develop approaches to facilitate this, which also applies to playground design. The design of PlayLab Cph was based on relevant evidence......, best practice, and the theories of Affordances and Behaviour Settings. A post-occupancy evaluation was carried out through a questionnaire survey and observation studies, which revealed that a majority of the potential evidence-based affordances were actualised, and that the application of the theories...

  17. Oil-based paint poisoning

    Science.gov (United States)

    Paint - oil based - poisoning ... Hydrocarbons are the primary poisonous ingredient in oil paints. Some oil paints have heavy metals such as lead, mercury, cobalt, and barium added as pigment. These heavy metals can cause additional ...

  18. Industry Based Survey (IBS) Yellowtail

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The "Southern New England Yellowtail Flounder Industry-Based Survey" was a collaboration between the Rhode Island Division of Fish and Wildlife and the fishing...

  19. Consent Based Verification System (CBSV)

    Data.gov (United States)

    Social Security Administration — CBSV is a fee-based service offered by SSA's Business Services Online (BSO). It is used by private companies to verify the SSNs of their customers and clients that...

  20. Content Based Video Retrieval Systems

    Directory of Open Access Journals (Sweden)

    B V Patel

    2012-05-01

    Full Text Available With the development of multimedia data types and available bandwidth there is huge demand of video retrieval systems, as users shift from text based retrieval systems to content based retrieval systems. Selection of extracted features play an important role in content based video retrieval regardless of video attributes being under consideration. These features are intended for selecting, indexing and ranking according to their potential interest to the user. Good features selection also allows the time and space costs of the retrieval process to be reduced. This survey reviews the interesting features that can beextracted from video data for indexing and retrieval along with similarity measurement methods. We also identify present research issues in area of content based video retrieval systems.

  1. US Air Force Base Observations

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Hourly observations taken by U.S. Air Force personnel at bases in the United States and around the world. Foreign observations concentrated in the Middle East and...

  2. Random Decrement Based FRF Estimation

    DEFF Research Database (Denmark)

    Brincker, Rune; Asmussen, J. C.

    The problem of estimating frequency response functions and extracting modal parameters is the topic of this paper. A new method based on the Random Decrement technique combined with Fourier transformation and the traditional pure Fourier transformation based approach is compared with regard to...... speed and quality. The basis of the new method is the Fourier transformation of the Random Decrement functions which can be used to estimate the frequency response functions. The investigations are based on load and response measurements of a laboratory model of a 3 span bridge. By applying both methods...... to these measurements the estimation time of the frequency response functions can be compared. The modal parameters estimated by the methods are compared. It is expected that the Random Decrement technique is faster than the traditional method based on pure Fourier Transformations. This is due to the...

  3. Random Decrement Based FRF Estimation

    DEFF Research Database (Denmark)

    Brincker, Rune; Asmussen, J. C.

    1997-01-01

    The problem of estimating frequency response functions and extracting modal parameters is the topic of this paper. A new method based on the Random Decrement technique combined with Fourier transformation and the traditional pure Fourier transformation based approach is compared with regard to...... speed and quality. The basis of the new method is the Fourier transformation of the Random Decrement functions which can be used to estimate the frequency response functions. The investigations are based on load and response measurements of a laboratory model of a 3 span bridge. By applying both methods...... to these measurements the estimation time of the frequency response functions can be compared. The modal parameters estimated by the methods are compared. It is expected that the Random Decrement technique is faster than the traditional method based on pure Fourier Transformations. This is due to the...

  4. Chip-based droplet sorting

    Energy Technology Data Exchange (ETDEWEB)

    Beer, Neil Reginald; Lee, Abraham; Hatch, Andrew

    2014-07-01

    A non-contact system for sorting monodisperse water-in-oil emulsion droplets in a microfluidic device based on the droplet's contents and their interaction with an applied electromagnetic field or by identification and sorting.

  5. Chip-based droplet sorting

    Science.gov (United States)

    Beer, Neil Reginald; Lee, Abraham; Hatch, Andrew

    2014-07-01

    A non-contact system for sorting monodisperse water-in-oil emulsion droplets in a microfluidic device based on the droplet's contents and their interaction with an applied electromagnetic field or by identification and sorting.

  6. Kernel model-based diagnosis

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The methods for computing the kemel consistency-based diagnoses and the kernel abductive diagnoses are only suited for the situation where part of the fault behavioral modes of the components are known. The characterization of the kernel model-based diagnosis based on the general causal theory is proposed, which can break through the limitation of the above methods when all behavioral modes of each component are known. Using this method, when observation subsets deduced logically are respectively assigned to the empty or the whole observation set, the kernel consistency-based diagnoses and the kernel abductive diagnoses can deal with all situations. The direct relationship between this diagnostic procedure and the prime implicants/implicates is proved, thus linking theoretical result with implementation.

  7. Hospital Value-Based Purchasing

    Data.gov (United States)

    U.S. Department of Health & Human Services — Hospital Value-Based Purchasing (VBP) is part of the Centers for Medicare and Medicaid Services (CMS) long-standing effort to link Medicares payment system to a...

  8. Cage-based performance capture

    CERN Document Server

    Savoye, Yann

    2014-01-01

    Nowadays, highly-detailed animations of live-actor performances are increasingly easier to acquire and 3D Video has reached considerable attentions in visual media production. In this book, we address the problem of extracting or acquiring and then reusing non-rigid parametrization for video-based animations. At first sight, a crucial challenge is to reproduce plausible boneless deformations while preserving global and local captured properties of dynamic surfaces with a limited number of controllable, flexible and reusable parameters. To solve this challenge, we directly rely on a skin-detached dimension reduction thanks to the well-known cage-based paradigm. First, we achieve Scalable Inverse Cage-based Modeling by transposing the inverse kinematics paradigm on surfaces. Thus, we introduce a cage inversion process with user-specified screen-space constraints. Secondly, we convert non-rigid animated surfaces into a sequence of optimal cage parameters via Cage-based Animation Conversion. Building upon this re...

  9. Detector Based Radio Tomographic Imaging

    OpenAIRE

    Yiğitler, Hüseyin; Jäntti, Riku; Kaltiokallio, Ossi; Patwari, Neal

    2016-01-01

    Received signal strength based radio tomographic imaging is a popular device-free indoor localization method which reconstructs the spatial loss field of the environment using measurements from a dense wireless network. Existing methods solve an associated inverse problem using algebraic or compressed sensing reconstruction algorithms. We propose an alternative imaging method that reconstructs spatial field of occupancy using a back-projection based reconstruction algorithm. The introduced sy...

  10. Donor Schiff Base Polymeric Complexes

    Directory of Open Access Journals (Sweden)

    Shubhangi N. Kotkar

    2013-01-01

    Full Text Available A series of new polymeric complexes of Mn(II, Co(II, Ni(II, Cu(II, and Zn(II were prepared with a Schiff base ligand derived from condensation of 2,4-dihydroxy acetophenone and p-phenylene diamine and characterized by elemental analysis and IR and NMR spectral data. The antimicrobial activity of the Schiff base and its polymeric complexes have been studied.

  11. Lazy Transformation-Based Learning

    OpenAIRE

    Samuel, Ken

    1998-01-01

    We introduce a significant improvement for a relatively new machine learning method called Transformation-Based Learning. By applying a Monte Carlo strategy to randomly sample from the space of rules, rather than exhaustively analyzing all possible rules, we drastically reduce the memory and time costs of the algorithm, without compromising accuracy on unseen data. This enables Transformation- Based Learning to apply to a wider range of domains, as it can effectively consider a larger number ...

  12. Leather inspection based on wavelets

    OpenAIRE

    Sobral, João Luís Ferreira

    2005-01-01

    This paper presents a new methodology to detect leather defects, based on the wavelet transform. The methodology uses a bank of optimised filters, where each filter is tuned to one defect type. Filter shape and wavelet sub-band are selected based the maximisation of the ratio between features values on defect regions and on normal regions. The proposed methodology can detect defects even when small features variations are present, which are not detect by generic texture classification techniq...

  13. Formalization in Component Based Development

    DEFF Research Database (Denmark)

    Holmegaard, Jens Peter; Knudsen, John; Makowski, Piotr;

    2006-01-01

    We present a unifying conceptual framework for components, component interfaces, contracts and composition of components by focusing on the collection of properties or qualities that they must share. A specific property, such as signature, functionality behaviour or timing is an aspect. Each aspe...... by small examples, using UML as concrete syntax for various aspects, and is illustrated by one larger case study based on an industrial prototype of a complex component based system....

  14. Identity Based Color Image Cryptography

    OpenAIRE

    Gopi Krishnan S; Loganathan D

    2011-01-01

    An Identity based cryptography based on visual cryptography scheme was proposed for protecting color image. A color image to be protected and authentic entities such as account number, password, signature image are given as input. The binary key image is obtained by distributing the digital signature of obtained authentic entities. A secret color image which needs to be communicated is decomposed into three grayscale tones of Y-Cb-Cr color component. Then these grayscale images are half-toned...

  15. Seeing graphene-based sheets

    OpenAIRE

    Jaemyung Kim; Franklin Kim; Jiaxing Huang

    2010-01-01

    Graphene-based sheets such as graphene, graphene oxide and reduced graphene oxide have stimulated great interest due to their promising electronic, mechanical and thermal properties. Microscopy imaging is indispensable for characterizing these single atomic layers, and oftentimes is the first measure of sample quality. This review provides an overview of current imaging techniques for graphene-based sheets and highlights a recently developed fluorescence quenching microscopy technique that al...

  16. Fuzzy Bases of Fuzzy Domains

    OpenAIRE

    Sanping Rao; Qingguo Li

    2013-01-01

    This paper is an attempt to develop quantitative domain theory over frames. Firstly, we propose the notion of a fuzzy basis, and several equivalent characterizations of fuzzy bases are obtained. Furthermore, the concept of a fuzzy algebraic domain is introduced, and a relationship between fuzzy algebraic domains and fuzzy domains is discussed from the viewpoint of fuzzy basis. We finally give an application of fuzzy bases, where the image of a fuzzy domain can be preserved under some special ...

  17. Brain plasticity-based therapeutics

    OpenAIRE

    Merzenich, Michael M.; Van Vleet, Thomas M.; Nahum, Mor

    2014-01-01

    The primary objective of this review article is to summarize how the neuroscience of brain plasticity, exploiting new findings in fundamental, integrative and cognitive neuroscience, is changing the therapeutic landscape for professional communities addressing brain-based disorders and disease. After considering the neurological bases of training-driven neuroplasticity, we shall describe how this neuroscience-guided perspective distinguishes this new approach from (a) the more-behavioral, tra...

  18. Brain Plasticity-Based Therapeutics

    OpenAIRE

    Michael eMerzenich; Mor eNahum; Tom eVan Vleet

    2014-01-01

    The primary objective of this review article is to summarize how the neuroscience of brain plasticity, exploiting new findings in fundamental, integrative and cognitive neuroscience, is changing the therapeutic landscape for professional communities addressing brain-based disorders and disease. After considering the neurological bases of training-driven neuroplasticity, we shall describe how this neuroscience-guided perspective distinguishes this new approach from a) the more-behavioral, trad...

  19. Dimensions of problem based learning

    DEFF Research Database (Denmark)

    Nielsen, Jørgen Lerche; Andreasen, Lars Birch

    2013-01-01

    The article contributes to the literature on problem based learning and problem-oriented project work, building on and reflecting the experiences of the authors through decades of work with problem-oriented project pedagogy. The article explores different dimensions of problem based learning...... and Learning (MIL). We discuss changes in the roles of the teachers as supervisors within this learning environment, and we explore the involvement of students as active participants and co-designers of how course and project activities unfold....

  20. Knowledge-based Telecom Industry

    OpenAIRE

    Vinje, Villeman; Nordkvelde, Marius

    2011-01-01

    BI Norwegian School of Management is conducting a national research project entitled “A knowledge-based Norway”. Thirteen major knowledge-based industries in Norway are being analyzed under the auspices of the project. This study assesses the underlying properties of a global knowledge hub to examine the extent to which the Norwegian telecom industry – which encompasses all telecom firms located in Norway regardless of ownership – constitutes a global knowledge hub. It commences with a ge...