Optimal Operation of Network-Connected Combined Heat and Powers for Customer Profit Maximization
Directory of Open Access Journals (Sweden)
Da Xie
2016-06-01
Full Text Available Network-connected combined heat and powers (CHPs, owned by a community, can export surplus heat and electricity to corresponding heat and electric networks after community loads are satisfied. This paper proposes a new optimization model for network-connected CHP operation. Both CHPs’ overall efficiency and heat to electricity ratio (HTER are assumed to vary with loading levels. Based on different energy flow scenarios where heat and electricity are exported to the network from the community or imported, four profit models are established accordingly. They reflect the different relationships between CHP energy supply and community load demand across time. A discrete optimization model is then developed to maximize the profit for the community. The models are derived from the intervals determined by the daily operation modes of CHP and real-time buying and selling prices of heat, electricity and natural gas. By demonstrating the proposed models on a 1 MW network-connected CHP, results show that the community profits are maximized in energy markets. Thus, the proposed optimization approach can help customers to devise optimal CHP operating strategies for maximizing benefits.
Wan, Chun Feng
2016-03-28
Pressure retarded osmosis (PRO) is a promising technology to reduce the specific energy consumption and the operating expenditure of a seawater reverse osmosis (SWRO) plant. In this study, a simple analytical PRO model is developed to predict the PRO performance as the dilution of draw solutions occurs. The model can predict the PRO performance with a high accuracy without carrying out complicated integrations and experiments. The operating profit of SWRO-PRO is also studied by calculating the profit generated for every m3 of seawater entering the process because maximizing the operating profit is the uttermost objective of the SWRO-PRO process. Based on the PRO analytical model, the operating profit and the dynamics of the SWRO-PRO process, a strategy has been proposed to maximize the operating profit of the SWRO-PRO process while maintaining the highest power density of the PRO membranes. This study proves that integration of SWRO with PRO can (1) push the SWRO to a higher recovery and maintain its high profitability, (2) effectively reduce the specific energy consumption of desalination by up to 35% and (3) increase the operating profit up to 100%. © 2016 Elsevier Ltd.
Directory of Open Access Journals (Sweden)
Muhammad Saad Memon
2015-01-01
Full Text Available Product recall gains considerable importance in recent times; the reason may be the huge losses faced by manufacturers because of product recall issues. Furthermore, the revenue of the firm is immensely affected as a result of product recall, which may lead to serious outcomes. Huge recall cost (such as repairing or destroying the recalled products and cost of notification occurs as a result of large recall. Therefore, in order to minimize the quantity and probability of recalls the traceability systems are widely used and considered as a necessary part of product safety strategies. However, from literature it is clear that manufacturers are still struggling to obtain the significant results. This study helps the managers to understand the importance of recall cost by analysing its impact on shareholders profit. Keeping in view the importance of problem, the paper proposed an integrated optimization model to minimize the expected loss to shareholders in recall crisis using batch dispersion methodology. The analysed results show that reduction in traceability level increases the expected shareholders losses while decreasing the operational costs. This will help managers to optimally set the production batch sizes in order to reduce the product recall impact.
THE CONSTITUTION, ORGANIZATION AND OPERATION OF NON-PROFIT ORGANIZATIONS
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DUMITRU FRANCA
2012-05-01
Full Text Available Non-profit organizations are associations, foundations or federations which use their own assets and revenues in order to pursue activities of general, community or non-patrimonial purpose. According to these legal regulations, associations and foundations can be constituted by natural or legal persons with the purpose of undertaking such activities of general, community or non-patrimonial (non-profit purpose. The organization and operation of non-profit organizations presents a series of particularities in the case of associations as opposed to foundations, but there are also common elements.
Profitability and optimization of data management
Energy Technology Data Exchange (ETDEWEB)
Boussa, M. [Sonatrach, Alger (Algeria). Petroleum Engineering and Development
2008-07-01
Information systems and technologies for the oil and gas industry were discussed with particular reference to the use of data analysis in dynamic planning processes. This paper outlined the risks and challenges associated with reorganizing data systems and the costs associated with equipment and software purchases. Issues related to Intranet encryption and electronic commerce systems were also reviewed along with the impact of the Internet on the oil and gas industry. New methods for using real time data systems for updating well data were outlined together with recent developments in Intranet and Extranet technologies and services. Other topics of discussion included new software applications for network optimization and nodal analyses; industry-specific software developed for well testing and reservoir engineering; and simulation and management production software. Data management solutions for storing, retrieving and analyzing data streams were presented. It was concluded that successful organizations must develop accurate data systems in order to ensure continuing success. 4 refs., 8 figs.
Optimal foraging in marine ecosystem models: selectivity, profitability and switching
DEFF Research Database (Denmark)
Visser, Andre W.; Fiksen, Ø.
2013-01-01
their diets towards the most profitable prey items. We present a simple algorithm for plankton feeding on a size-spectrum of prey with particular energetic content, handling times and capture probabilities. We show that the optimal diet breadth changes with relative densities, but in a different way...
Profit and Risk Measures in Oil Production Optimization
DEFF Research Database (Denmark)
Capolei, Andrea; Foss, Bjarne; Jørgensen, John Bagterp
2015-01-01
on the value of the uncertain parameters. In this case, a problem reformulation is needed to properly define the optimization problem. In this paper we describe the concept of risk and we explore how to handle the risk by using appropriate risk measures. We provide a review on various risk measures reporting...... pro and cons for each of them. Finally, among the presented risk measures, we identify two of them as appropriate risk measures when minimizing the risk.......In oil production optimization, we usually aim to maximize a deterministic scalar performance index such as the profit over the expected reservoir lifespan. However, when uncertainty in the parameters is considered, the profit results in a random variable that can assume a range of values depending...
Reference Tracking and Profit Optimization of a Power Plant
DEFF Research Database (Denmark)
Kragelund, Martin Nygaard; Leth, John-Josef; Wisniewski, Rafal
2010-01-01
In this paper we discuss two different methods for implementing reference tracking intro a profit optimization problem of a power plant. It is shown that tracking included as a side constraint results in an significant tracking error only when the reference gradient is large. When tracking...... is included in the cost function, as a quadratic term, the reference is tracked with a small accumulated error. Finally, the two methods are compared both in terms of tracking performance and computational burden....
Optimality of Profit-Including Prices Under Ideal Planning
Samuelson, Paul A.
1973-01-01
Although prices calculated by a constant percentage markup on all costs (nonlabor as well as direct-labor) are usually admitted to be more realistic for a competitive capitalistic model, the view is often expressed that, for optimal planning purposes, the “values” model of Marx's Capital, Volume I, is to be preferred. It is shown here that an optimal-control model that maximizes discounted social utility of consumption per capita and that ultimately approaches a steady state must ultimately have optimal pricing that involves equal rates of steady-state profit in all industries; and such optimal pricing will necessarily deviate from Marx's model of equal rates of surplus value (markups on direct-labor only) in all industries. PMID:16592102
An Econometric Analysis of the Operating Profit of Romanian Companies
Adriana DEACONU
2011-01-01
This paper aims to contribute to the empirical literature by employing a panel data model for analysing the connection between operating profit of Romanian companies and the turnover, tangible assets, payrolls, stocks and cash. We find that the companies with a higher turnover recorded better economic results and an increased payroll is associated with a decline in economic performance. Likewise, companies that have the cash and / or tangible assets registered superior performance, while grow...
Profit Optimization in SLA-Aware Cloud Services with a Finite Capacity Queuing Model
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Yi-Ju Chiang
2014-01-01
Full Text Available Cloud computing realizes a utility computing paradigm by offering shared resources through an Internet-based computing. However, how a system control can enhance profit and simultaneously satisfy the service level agreements (SLAs has become one of the major interests for cloud providers. In this paper, a cloud server farm provided with finite capacity is modeled as an M/M/R/K queuing system. Revenue losses are estimated according to the system controls and impatient customer behaviors. Three important issues are solved in this paper. First, a profit function is developed in which both the system blocking loss and the user abandonment loss are evaluated in total revenue. A tradeoff between meeting system performances and reducing operating costs is conducted. Second, the effects of system capacity control and utilization on various performances of waiting time, loss probability, and final arrival rate are demonstrated. Finally, the proposed optimal profit control (OPC policy allows a cloud provider to make the optimal decision in the number of servers and system capacity, so as to maximize profit. As compared to a system without applying the OPC policy, enhancing providers’ profit and improving system performances can be obtained.
Using Cotton Model Simulations to Estimate Optimally Profitable Irrigation Strategies
Mauget, S. A.; Leiker, G.; Sapkota, P.; Johnson, J.; Maas, S.
2011-12-01
In recent decades irrigation pumping from the Ogallala Aquifer has led to declines in saturated thickness that have not been compensated for by natural recharge, which has led to questions about the long-term viability of agriculture in the cotton producing areas of west Texas. Adopting irrigation management strategies that optimize profitability while reducing irrigation waste is one way of conserving the aquifer's water resource. Here, a database of modeled cotton yields generated under drip and center pivot irrigated and dryland production scenarios is used in a stochastic dominance analysis that identifies such strategies under varying commodity price and pumping cost conditions. This database and analysis approach will serve as the foundation for a web-based decision support tool that will help producers identify optimal irrigation treatments under specified cotton price, electricity cost, and depth to water table conditions.
Optimization of Non-Profit Projects’ Portfolio: Chosen Aspects and Assumptions
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Jacek Woźniak
2014-09-01
Full Text Available The chosen aspects and assumptions of the author’s proposal of the optimization model of the non-profit projects’ portfolio are presented. The functional model of the non-profit sector (third sector, which is the base for the further analyses, is also characterized. The article also contains the quantification of fundamental conditions of portfolio optimization. There is developed the utility model for the management system in the non-profit portfolio, in the framework of which there are specified the scope of the model and relationships between four categories of the non-profit portfolio’s participants/stakeholders: non-profit organizations, donors, co-participants and customers (recipients of the basic benefits/values associated with the realization of the non-profit projects. The main optimality conditions and optimization algorithm of the non-profit portfolio are also given. The paper is concluded with exemplary analytical matrixes used for optimization of the non-profit portfolios and based on the evaluation of both the optimization utility conditions and added parameters. Only basic and chosen aspects of the optimization of the non-profit projects’ portfolio have been described here. [b]Keywords[/b]: Management, Organization, Non-Profit, Project, Portfolio, Optimization, Utility
Optimization of the bank's operating portfolio
Borodachev, S. M.; Medvedev, M. A.
2016-06-01
The theory of efficient portfolios developed by Markowitz is used to optimize the structure of the types of financial operations of a bank (bank portfolio) in order to increase the profit and reduce the risk. The focus of this paper is to check the stability of the model to errors in the original data.
Wealth Financialization: Operating Profit as Conditioning of Financial Revenue
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Andréia Ribeiro Da Luz
2015-04-01
Full Text Available Objective. Due to the deregulation of the financial market in 80s decade, the financialization of wealth has become a globalized systemic pattern, giving companies greater access to financial innovations. In view of the above, the objective is to analyze whether the appreciation of capital through the financial system is preferred over the capital appreciation through production.Methodology. This is a descriptive research slitting with cross-sectional perspective, in which we considered information belonging to 106 listed non-financial companies in Brazil (2004–2012.Findings. This study suggests that operating income influences financial income positively.Limitations. The study includes just industrial sector companies in a specific period.Originality/Value. We discuss measuring instruments for analyzing the wealth financialization as a condition of operating profit gains from the financial market.Copyright © 2015 Instituto Brasileiro de Inovação Financeira All rights reserved.
Computational Approach to Profit Optimization of a Loss-Queueing System
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Dinesh Kumar Yadav
2010-01-01
Full Text Available Objective of the paper is to deal with the profit optimization of a loss queueing system with the finite capacity. Here, we define and compute total expected cost (TEC, total expected revenue (TER and consequently we compute the total optimal profit (TOP of the system. In order to compute the total optimal profit of the system, a computing algorithm has been developed and a fast converging N-R method has been employed which requires least computing time and lesser memory space as compared to other methods. Sensitivity analysis and its observations based on graphics have added a significant value to this model.
The Optimization of Capital Structure in Maximizing Profit and Corporate Value
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Kharisya Ayu Effendi
2017-05-01
Full Text Available The purpose of this research was to determine the optimal capital structure which could maximize profits and corporate value. The benefits of this research were companies knew clearly that optimal capital structure could maximize profits and corporate value. The method used was quantitative descriptive analysis. Moreover, the data used was secondary data in the Jakarta Islamic Index (JII from 2011 to 2015. The results of this research are companies which have optimal capital structure are in line with the trade-off theory models. The capital structure is optimal if the debt levels are to a certain extent so that the corporate value will increase . However, if the debt limit passes the certain degree, profit and corporate value will decrease. Meanwhile, pecking order theory in this research does not conform and cannot be said to be optimal, because of the low debt level describing the opposite result with the theory as low profits.
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Saladin Ghalib
2017-06-01
Full Text Available After the Asian crisis in 1998, Indonesian banking transformed very quickly into more market-oriented banking. This development increased the competition, on the one hand, and pressure to perform better financially, especially after foreign investor taking over the ownership, on the other hand. Some banks transformed their business strategies into a microfinance bank for profit motives. Such strategy jointly results in significant profitability and efficiency. Using SUR regression, it is found that for the profitability equation, the profitability relates to the size of the bank, the loan loss reserve to gross loan (LLRGL, equity ratio (ETA and fixed asset ratio (FIXASEQ. For operating efficiency (CIR, the result is similar and only the sign is different. Interestingly that for profitability, the microfinance strategy (MFS is significant, but not for operating cost efficiency. It implies the need for more cost efficient commercial banks entering microfinance business as it will benefit small borrowers in terms of lower interest margin.
Jaan Alver
2005-01-01
A cash flow statement is required as part of a complete set of financial statements prepared in conformity with IFRS as well as US GAAP for all business enterprises. IAS 7 lays down a formal structure for the cash flow statement. Cash flows should be classified under the following three standard headings: íOperating activitiesî, íInvesting activitiesî, íFinancing activitiesî. The classification of cash flows among operating, investing and financing activities is essential to the analysis of c...
PROFIT MAXIMIZATION AND OPTIMAL SIZING OF RENEWABLE ENERGY SOURCES IN A HYBRID SYSTEM
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YAJVENDER PAL VERMA
2010-09-01
Full Text Available The renewable energy sources wind, solar etc. have become very essential and important in the generation mix as a result of rising energy demand and environmental reasons. In addition tax is being imposed on high carbon emission. But the uncertainty and variability associated with renewable such as wind may result in economical andtechnical problems in the power system. In order to compensate wind intermittency, generation resources such as gas plant, pumped storage unit etc. are employed due to their lesser start up time, lower operating cost and good ramping capabilities. This paper proposes a model which investigates the combined operation of thermal, wind andpumped storage units for the profit maximization in varying wind, load, and price scenarios. The optimal size of the pumped storage unit to be used has been obtained after putting the system to different operating conditions such as varying wind power and load demand, imposing tax on carbon emission and varying ramping limits etc. The model has been applied on IEEE-30 bus test data and satisfactory results have been obtained for optimal hybrid systemoperation.
Directory of Open Access Journals (Sweden)
Barbara Langland-Orban PhD
2015-08-01
Full Text Available Medicare Advantage was implemented in 2004 and the Recovery Audit Contractor (RAC program was implemented in Florida during 2005. Both increase surveillance of medical necessity and deny payments for improper admissions. The purpose of the present study was to determine their potential impact on for-profit (FP and not-for-profit (NFP hospital operating margins in Florida. FP hospitals were expected to be more adversely affected as admissions growth has been one strategy to improve stock performance, which is not a consideration at NFPs. This study analyzed Florida community hospitals from 2000 through 2010, assessing changes in pre-tax operating margin (PTOM. Florida Agency for Health Care Administration data were analyzed for 104 community hospitals (62 FPs and 42 NFPs. Academic, public, and small hospitals were excluded. A mixed-effects model was used to assess the association of RAC implementation, organizational and payer type variables, and ownership interaction effects on PTOM. FP hospitals began the period with a higher average PTOM, but converged with NFPs during the study period. The average Medicare Advantage effect was not significant for either ownership type. The magnitude of the RAC variable was significantly negative for average PTOM at FPs (−4.68 and positive at NFPs (0.08, meaning RAC was associated with decreasing PTOM at FP hospitals only. RAC complements other Medicare surveillance systems that detect medically unnecessary admissions, coding errors, fraud, and abuse. Since its implementation in Florida, average FP and NFP operating margins have been similar, such that the higher margins reported for FP hospitals in the 1990s are no longer evident.
A Methodology to Exploit Profit Allocation in Logistics Joint Distribution Network Optimization
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Yong Wang
2015-01-01
Full Text Available Logistics joint distribution network (LJDN optimization involves vehicle routes scheduling and profit allocation for multiple distribution centers. This is essentially a combinational and cooperative game optimization problem seeking to serve a number of customers with a fleet of vehicles and allocate profit among multiple centers. LJDN routing optimization based on customer clustering units can alleviate the computational complexity and improve the calculation accuracy. In addition, the profit allocation mechanism can be realized based on cooperative game theory through a negotiation procedure by the Logistics Service Provider (LSP. This paper establishes a model to minimize the total cost of the multiple centers joint distribution network when each distribution center is assigned to serve a series of distribution units. An improved particle swarm optimization (PSO algorithm is presented to tackle the model formulation by assigning distribution centers (DCs to distribution units. Improved PSO algorithm combines merits of PSO algorithm and genetic algorithm (GA with global and local search capabilities. Finally, a Shapley value model based on cooperative game theory is proposed to obtain the optimal profit allocation strategy among distribution centers from nonempty coalitions. The computational results from a case study in Guiyang city, China, suggest the optimal sequential coalition of distribution centers can be achieved according to Strictly Monotonic Path (SMP.
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S. Sajedi
2012-03-01
Full Text Available This study proposes joint operation of power plant and electric energy storage plant in order to maximizing overall profit in a restructured electricity market. The goal is investigating the coupling efficiency on profit increment considering various intensities of power plant’s fuel constraint. In order to reach this goal, the amount of overall profits of fuel-constrained power plant, battery plant and their coupling are first calculated in a specific time interval. Then, the coupling efficiency is determined using incremental profit rate. Having an appropriate strategy to calculate this parameter is essential. Hence, a comprehensive approach to selfschedule of individual and coupled plants is developed. This comprehensive self-scheduling approach is therefore formulated and solved as a Mixed Integer Non-linear Programming (MINLP problem. Numerical results for a case study are discussed.
Wu, Kai; Liu, Jing; Wang, Shuai
2016-11-01
Evolutionary games (EG) model a common type of interactions in various complex, networked, natural and social systems. Given such a system with only profit sequences being available, reconstructing the interacting structure of EG networks is fundamental to understand and control its collective dynamics. Existing approaches used to handle this problem, such as the lasso, a convex optimization method, need a user-defined constant to control the tradeoff between the natural sparsity of networks and measurement error (the difference between observed data and simulated data). However, a shortcoming of these approaches is that it is not easy to determine these key parameters which can maximize the performance. In contrast to these approaches, we first model the EG network reconstruction problem as a multiobjective optimization problem (MOP), and then develop a framework which involves multiobjective evolutionary algorithm (MOEA), followed by solution selection based on knee regions, termed as MOEANet, to solve this MOP. We also design an effective initialization operator based on the lasso for MOEA. We apply the proposed method to reconstruct various types of synthetic and real-world networks, and the results show that our approach is effective to avoid the above parameter selecting problem and can reconstruct EG networks with high accuracy.
Small is profitable: No support for the optimal foraging theory in sea stars
Hummel, C.; Honkoop, P.; van der Meer, J.
2011-01-01
Doubt has been shed recently on the most popular optimal foraging theory stating that predators should maximize prey profitability, i.e., select that prey item that contains the highest energy content per handling time. We hypothesized that sea stars do not forage on blue mussels according to the cl
Optimization purchase price and the profit policy under vendor managed inventory
Institute of Scientific and Technical Information of China (English)
Guo Haifeng; Huang Xiaoyuan
2005-01-01
The optimization policy of the purchase price and the profit under vendor managed inventory(VMI) is studied.For a salable product, supply chain mode of VMI is established, which is based on deterministic demand, having initial stock and having stock-out cost. With the further analysis of the mode, VMI is found to increase profits of the buyer in the short-term motivation. But VMI will reduce profits of the supplier under the matching condition. And in the shortterm motivation, VMI will increase the purchase price to compensate the transfer cost of the supplier. As a result, the foundation of theory is provided to implement VMI in the supply chain, and have some definituded project significance.
S. A. Effiong; J. O. Udoayang; A. I. Asuquo
2011-01-01
The study investigated the correlation and differential influence of historical cost and current cost profits on the operating capabilities of the firm. The financial statements of thirty-one Nigerian Companies were surveyed and adjusted for effects of price changes using the Consumers¡¯ Price Index (CPI). Correlation influence between the historical cost profits on the operating ability of the firm was measured and established on one hand and that of current cost profit on the other hand. Di...
Optimal stopping of expected profit and cost yields in an investment under uncertainty
Djehiche, Boualem; Morlais, Marie Amélie
2010-01-01
We consider a finite horizon optimal stopping problem related to trade-off strategies between expected profit and cost cash-flows of an investment under uncertainty. The optimal problem is first formulated in terms of a system of Snell envelopes for the profit and cost yields which act as obstacles to each other. We then construct both a minimal and a maximal solutions using an approximation scheme of the associated system of reflected backward SDEs. When the dependence of the cash-flows on the sources of uncertainty, such as fluctuation market prices, assumed to evolve according to a diffusion process, is made explicit, we also obtain a connection between these solutions and viscosity solutions of a system of variational inequalities (VI) with interconnected obstacles. We also provide two counter-examples showing that uniqueness of solutions of (VI) does not hold in general.
Improving CLOPE’s Profit Value and Stability with an Optimized Agglomerative Approach
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Yefeng Li
2015-06-01
Full Text Available CLOPE (Clustering with sLOPE is a simple and fast histogram-based clustering algorithm for categorical data. However, given the same data set with the same input parameter, the clustering results by this algorithm would possibly be different if the transactions are input in a different sequence. In this paper, a hierarchical clustering framework is proposed as an extension of CLOPE to generate stable and satisfactory clustering results based on an optimized agglomerative merge process. The new clustering profit is defined as the merge criteria and the cluster graph structure is proposed to optimize the merge iteration process. The experiments conducted on two datasets both demonstrate that the agglomerative approach achieves stable clustering results with a better profit value, but costs much more time due to the worse complexity.
The Practice of an Optimal Pricing Strategy for Maximizing Store Profits Using PRISM
YADA, Katsutoshi; 矢田, 勝俊; OHNO, Kousuke
2006-01-01
© 2006 IEEE. Reprinted, with permission, from YADA Katsutoshi, OHNO Kousuke , The Practice of an Optimal Pricing Strategy for Maximizing Store Profits Using PRISM, 10/2006. This material is posted here with permission of the IEEE. Such permission of the IEEE does not in any way imply IEEE endorsement of any of Kansai University'sproducts or services. Internal or personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotion...
Optimization of power system operation
Zhu, Jizhong
2015-01-01
This book applies the latest applications of new technologies topower system operation and analysis, including new and importantareas that are not covered in the previous edition. Optimization of Power System Operation covers both traditional andmodern technologies, including power flow analysis, steady-statesecurity region analysis, security constrained economic dispatch,multi-area system economic dispatch, unit commitment, optimal powerflow, smart grid operation, optimal load shed, optimalreconfiguration of distribution network, power system uncertaintyanalysis, power system sensitivity analysis, analytic hierarchicalprocess, neural network, fuzzy theory, genetic algorithm,evolutionary programming, and particle swarm optimization, amongothers. New topics such as the wheeling model, multi-areawheeling, the total transfer capability computation in multipleareas, are also addressed. The new edition of this book continues to provide engineers andac demics with a complete picture of the optimization of techn...
Directory of Open Access Journals (Sweden)
Mohammad Taghi Samadi
2012-08-01
Full Text Available Banking system plays an important role in boosting the economy and when they become profitable, they could help industries more efficiently. The proposed study of this paper attempts to investigate the effects of operating risk and capital structure on profitability of banking industry. The proposed study of this paper includes 17 commercial banks, which were active from 2006 to 2010 in Iran and the results of the study indicate that although there was a positive relationship between capital structure and profitability but there was no meaningful relationship between operating risk and capital structure. In addition, the results of our study mention that operating risks negatively impacts profitability and economic figures do not have any influence on profitability, operating risks and capital structure.
Optimizing the operating theatre environment.
Wong, Shing W; Smith, Richard; Crowe, Phil
2010-12-01
The operating theatre is a complex place. There are many potential factors which can interfere with surgery and predispose to errors. Optimizing the operating theatre environment can enhance surgeon performance, which can ultimately improve patient outcomes. These factors include the physical environment (such as noise and light), human factors (such as ergonomics), and surgeon-related factors (such as fatigue and stress). As individual factors, they may not affect surgical outcome but in combination, they may exert a significant influence. The evidence for some of these working environment factors are examined individually. Optimizing the operating environment may have a potentially more significant impact on overall surgical outcome than improving individual surgical skill.
Islam, Rafiqul
2013-07-01
Today's bioanalytical CROs face increasing global competition, highly variable demand, high fixed costs, pricing pressure, and increasing demand for quality and speed. Most bioanalytical laboratories have responded to these challenges by implementing automation and by implementing process improvement methodologies (e.g., Six Sigma). These solutions have not resulted in a significant improvement in productivity and profitability since none of them are able to predict the upturn or downturn in demand. High volatility of demand causes long lead times and high costs during peak demand and poor productivity during trough demand. Most bioanalytical laboratories lack the tools to align supply efficiently to meet changing demand. In this paper, sales and operation planning (S&OP) has been investigated as a tool to balance supply and demand. The S&OP process, when executed effectively, can be the single greatest determinant of profitability for a bioanalytical business.
Reflection in the non-profit legal persons accounting of the grant-oriented operations
Directory of Open Access Journals (Sweden)
Nătăliţa-Mihaela Lesconi Frumuşanu
2011-12-01
Full Text Available In this paper we will analyse the legal stipulations regarding the reflection in accounting of the grant-oriented (structural funds operations within a non-profit organization. The suitability and importance of the paper is obvious, since the grants constitute an important source of funds for this category of entities. The paper indicates, in addition to the specific accounting notes, the main problems the grant beneficiaries have to face regarding the organization and management of the project accounting, thus the paper having a profound practical nature.
DEFF Research Database (Denmark)
Larsen, Christian
2005-01-01
for the service but there is no waiting time, hence no waiting costs. Under the premises that the subcontractor prices his services in order to maximize his profit, we study two work allocation rules, which given the price of subcontractor seek to allocate work such that the costs of the customers are minimized......We study a service system modelled as a single server queuing system where request for service either can be processed at the service system or by a subcontractor. In the former case the customer is incurred waiting costs but the service is free, while in the latter case the customer must pay...... also show that from the customers point view, any of the two work allocation rules are to be preferred compared to the base case where there are no subcontractor. Udgivelsesdato: MAR...
The role of non-operating income in community benefit provision by not-for-profit hospitals.
Song, Paula H; McCullough, Jeffrey S; Reiter, Kristin L
2013-01-01
Not-for-profit hospitals are under increased public scrutiny for providing what some view as insufficient levels of community benefit compared to their tax-exempt benefits. One potential driver of community benefit is financial surplus, which arises from both patient care (operating) activities and non-patient care (non-operating) activities. This study addresses the effect of hospitals' non-operating income on not-for-profit hospitals' provision of community benefit. The study sample includes 217 unique not-for-profit, non-governmental, general, acute care hospitals in California between 1997 and 2010 that filed annual reports with the California Office of Statewide Health Planning and Development (OSHPD). We model the effect of hospitals' operating and non-operating incomes on hospitals' community benefit, controlling for observable hospital characteristics such as scale and system membership, local competition, time trends, and hospital fixed effects. Our results indicate that non-operating income has no effect on levels of community benefit provided by not-for-profit hospitals. This finding suggests that not-for-profit hospitals budget for uncompensated care at levels that are prioritized over other potential investments if non-operating income falls, but remain fixed if non-operating income rises.
Mousavi, Seyed Hosein; Nazemi, Ali; Hafezalkotob, Ashkan
2015-12-01
With the formation of the competitive electricity markets in the world, optimization of bidding strategies has become one of the main discussions in studies related to market designing. Market design is challenged by multiple objectives that need to be satisfied. The solution of those multi-objective problems is searched often over the combined strategy space, and thus requires the simultaneous optimization of multiple parameters. The problem is formulated analytically using the Nash equilibrium concept for games composed of large numbers of players having discrete and large strategy spaces. The solution methodology is based on a characterization of Nash equilibrium in terms of minima of a function and relies on a metaheuristic optimization approach to find these minima. This paper presents some metaheuristic algorithms to simulate how generators bid in the spot electricity market viewpoint of their profit maximization according to the other generators' strategies, such as genetic algorithm (GA), simulated annealing (SA) and hybrid simulated annealing genetic algorithm (HSAGA) and compares their results. As both GA and SA are generic search methods, HSAGA is also a generic search method. The model based on the actual data is implemented in a peak hour of Tehran's wholesale spot market in 2012. The results of the simulations show that GA outperforms SA and HSAGA on computing time, number of function evaluation and computing stability, as well as the results of calculated Nash equilibriums by GA are less various and different from each other than the other algorithms.
Sue-Ann, Goh; Ponnambalam, S. G.
This paper focuses on the operational issues of a Two-echelon Single-Vendor-Multiple-Buyers Supply chain (TSVMBSC) under vendor managed inventory (VMI) mode of operation. To determine the optimal sales quantity for each buyer in TSVMBC, a mathematical model is formulated. Based on the optimal sales quantity can be obtained and the optimal sales price that will determine the optimal channel profit and contract price between the vendor and buyer. All this parameters depends upon the understanding of the revenue sharing between the vendor and buyers. A Particle Swarm Optimization (PSO) is proposed for this problem. Solutions obtained from PSO is compared with the best known results reported in literature.
McCue, Michael J
2007-01-01
National benchmark data for 2002 indicate that large rural for-profit hospitals have a median cash flow margin of 19.5% compared to 9.2% for their nonprofit counterparts. This study aims to gain insight regarding the driving factors behind the high cash flow performance of large rural for-profit hospitals. Using 3 annual periods of Centers for Medicare and Medicaid cost report data with the last fiscal year ending between September 30, 2002, and August 30, 2003, the study found a cash flow margin of 21.5% for the large rural for-profit hospitals. All these facilities were owned by hospital management companies. To assess their underlying market, operational, and mission factors, these hospitals were compared to a similar comparison group of large rural nonprofit hospitals that are system owned and have positive cash flows. Using logistic regression analysis, the study found lower operating expense per adjusted discharge and salary expense as a percentage of total operating expense among large rural for-profit, system-owned hospitals with positive cash flows relative to nonprofits with similar traits. Overall, the findings of this study reflect how these for-profit hospitals, which are owned by hospital management companies, focus on controlling their labor costs as well as operating costs per discharge in order to achieve a greater positive cash flow position.
Following an Optimal Batch Bioreactor Operations Model
DEFF Research Database (Denmark)
Ibarra-Junquera, V.; Jørgensen, Sten Bay; Virgen-Ortíz, J.J.;
2012-01-01
The problem of following an optimal batch operation model for a bioreactor in the presence of uncertainties is studied. The optimal batch bioreactor operation model (OBBOM) refers to the bioreactor trajectory for nominal cultivation to be optimal. A multiple-variable dynamic optimization of fed-b...
Magnus, Stephen A; Wheeler, John R C; Smith, Dean G
2004-01-01
Increased debt in companies can motivate both operational and capital-investment efficiency. This positive influence of debt is attributed to creditors' oversight of corporate behavior and the need to generate cash flows to service debt. Our study investigates whether debt has a similar relationship with efficiency in not-for-profit hospitals. Using statistical analysis of a database of audited financial statements of not-for-profit hospitals, we test whether debt is associated with six distinct measures of operational and capital-investment efficiency. We find that debt either has no association with efficiency or predicts decreased efficiency. Possible explanations are that creditors' oversight is less tight in the not-for-profit setting and that debt may at times motivate excessive capital investment because of a legal requirement to tie tax-exempt debt with a capital-investment project.
Efficiency Comparison of Operational and Profitability: A Case of Hong Kong Commercial Banks
Directory of Open Access Journals (Sweden)
Cheng-Ru Wu
2008-01-01
Full Text Available Problem Statement: Traditional DEA models deal with measurements of relative efficiency of DMUs regarding multiple-inputs vs. multiple-outputs. One of the drawbacks of these models is the neglect of intermediate products or linking activities. The objectives of this study were: (i This research was shown how to use DEA by two stages, with outputs from the first stage becoming inputs in the second stage. (ii Comparative analysis of efficiency of bank manageable in Hong Kong. Approach: The research conducts a comparative analysis of efficiency of bank manageable in Hong Kong using a two-stage model, which evaluates their Operational Efficiency (OE and Profitability Efficiency (PE. The study period covered 2004-2006 and used two-stage Data Envelopment Analysis (DEA. Results: Large-sized banks are generally more efficient than small-sized ones in the operational efficiency; while small efficient banks are easily to become benchmarks, large efficient banks are deemed as competitive niche players. This means that the large banks have better competitive power than those of smaller ones. Conclusion: Using this model, we can evaluate divisional efficiencies along with the overall efficiency of decision making units (DMUs.
An integrated framework for gas turbine based power plant operational modeling and optimization
Zhao, Yongjun
The deregulation of the electric power market introduced a strong element of competition. Power plant operators strive to develop advanced operational strategies to maximize the profitability in the dynamic electric power market. New methodologies for gas turbine power plant operational modeling and optimization are needed for power plant operation to enhance operational decision making, and therefore to maximize power plant profitability by reducing operations and maintenance cost and increasing revenue. In this study, a profit based, lifecycle oriented, and unit specific methodology for gas turbine based power plant operational modeling was developed, with the power plant performance, reliability, maintenance, and market dynamics considered simultaneously. The generic methodology is applicable for a variety of optimization problems, and several applications were implemented using this method. A multiple time-scale method was developed for gas turbine power plants long term generation scheduling. This multiple time-scale approach allows combining the detailed granularity of the day-to-day operations with global (seasonal) trends, while keeping the resulting optimization model relatively compact. Using the multiple time-scale optimization method, a profit based outage planning method was developed, and the key factors for this profit based approach include power plant aging, performance degradation, reliability degradation, and, importantly, the energy market dynamics. Also a novel approach for gas turbine based power plant sequential preventive maintenance scheduling was introduced, and a profit based sequential preventive maintenance scheduling was developed for more effective maintenance scheduling. Methods to evaluate the impact of upgrade packages on gas turbine power plant performance, reliability, and economics were developed, and TIES methodology was applied for effective evaluation and selection of gas turbine power plant upgrade packages.
Ashmore, N J
1991-11-01
The healthcare market doesn't just mean hospitals anymore. For some textile rental operators, doctors' offices and medical clinics are a profitable and growing niche. On the positive side, this market offers growth, low abuse, good prices, and light soil. But operators also must weigh the cons--scattered deliveries, low volume, small stops, and medical waste management. Is the "other" healthcare market for you?
Optimal Operation of Energy Storage in Power Transmission and Distribution
Akhavan Hejazi, Seyed Hossein
uncertainty from various elements, such as solar photovoltaic , electric vehicle chargers, and residential baseloads, in the form of discrete probability functions. In the last part of this thesis we address some other resources and concepts for enhancing the operation of power distribution and transmission systems. In particular, we proposed a new framework to determine the best sites, sizes, and optimal payment incentives under special contracts for committed-type DG projects to offset distribution network investment costs. In this framework, the aim is to allocate DGs such that the profit gained by the distribution company is maximized while each DG unit's individual profit is also taken into account to assure that private DG investment remains economical.
Optimization of costs of Port Operations in Nigeria: A Scenario For ...
African Journals Online (AJOL)
2013-03-01
Mar 1, 2013 ... This study attempts to optimize the cost of port operations in Nigeria. The quantitative estimates ... its customers at a lower price and also be able to make profits. .... Based On Averages Of Different Kinds Of Cargo. SHIP/PORT ...
Joint optimization of customer segmentation and marketing policy to maximize long-term profitability
J-J. Jonker (Jedid-Jah); N. Piersma (Nanda); D. Van den Poel (Dirk)
2002-01-01
textabstractWith the advent of one-to-one marketing media, e.g. targeted direct mail or internet marketing, the opportunities to develop targeted marketing campaigns are enhanced in such a way that it is now both organizationally and economically feasible to profitably support a substantially larger
Olawale - Olakunle Olajumoke Elizabeth
2017-01-01
This paper examines effective slack management and its impact on the profitability of the hospitality operations. A sound and dynamic stock management strategy is indispensable in contemporary time where aggressive competition for survival is the common business trend coupled with rapid increase in technological acceleration. Secondary sources of data collection were employed to get relevant information. The result reveals that effective stock management is inevitably the bedrock upon which e...
Directory of Open Access Journals (Sweden)
Seyedeh Shideh Dianat Jahromi
2013-09-01
Full Text Available In some decades, capitalism countries have suffered from financial crises and the financial crises have created economic recession started from the country of origin and distributed to other counties. The purpose of this paper is to study the global financial crisis effects on the stock price as well as operating profit of some listed companies in Tehran Stock Exchange(TSE. This research shows the difference between operating profit and the price of the products of the firms before and after the global financial crisis. The aim of this research is to study the effects of the global financial crisis on 133 TSE firms over the period 2004-2011 by considering two periods: Before/after crisis, i.e. 2004-2008 and 2008-2011. The results of testing different hypotheses show that there was a significant difference between the operating profit and the stock price of the firms before and after the global financial crisis on the different industries of the Iranian companies.
Optimal operation of batch membrane processes
Paulen, Radoslav
2016-01-01
This study concentrates on a general optimization of a particular class of membrane separation processes: those involving batch diafiltration. Existing practices are explained and operational improvements based on optimal control theory are suggested. The first part of the book introduces the theory of membrane processes, optimal control and dynamic optimization. Separation problems are defined and mathematical models of batch membrane processes derived. The control theory focuses on problems of dynamic optimization from a chemical-engineering point of view. Analytical and numerical methods that can be exploited to treat problems of optimal control for membrane processes are described. The second part of the text builds on this theoretical basis to establish solutions for membrane models of increasing complexity. Each chapter starts with a derivation of optimal operation and continues with case studies exemplifying various aspects of the control problems under consideration. The authors work their way from th...
DEFF Research Database (Denmark)
Baldin, Andrea; Bille, Trine; Ellero, Andrea
The implementation of Revenue Management (RM) techniques in non profit performing arts organizations presents new challenges compared to other sectors, such as transportion or hospitality industries, in which these techniques are more consolidated. Indeed, performing arts organizations are charac......The implementation of Revenue Management (RM) techniques in non profit performing arts organizations presents new challenges compared to other sectors, such as transportion or hospitality industries, in which these techniques are more consolidated. Indeed, performing arts organizations...... is to incentive the customers to discriminate among themselves according to their reservation price, offering a schedule of different prices corresponding to different seats in the venue. In this context, price and allocation of the theatre seating area are decision variables that allow theatre managers to manage...... of heterogeneity among customer categories in both choice and demand. The proposed model is validated with booking data referring to the Royal Danish Theatre during the period 2010-2015....
Network Structure Expert System and Operation Optimization
Institute of Scientific and Technical Information of China (English)
刘洪谦; 袁希钢; 麻德贤
2003-01-01
It is proposed that double level programming technique may be adopted in synthesis strategy. Optimization of heat exchanger network structural configuration (the master problem) may be solved at the upper level, leaving the rest operating conditions( the slave problem) being optimized at the lower level. With the uniqueness in mind, an HEN synthesis expert system may be employed to address both the logical constraints and the global operation parameters′ optimization using enhanced sequential number optimization theory.Case studies demonstrate that the synthesis strategy proposed can effectively simplify both the problem-solving and the synthesis process. The validity of the strategy recommended is evidenced by case studies′ results compared.
Optimization and assistance operations; Optimisation et operations de secours
Energy Technology Data Exchange (ETDEWEB)
Giordan, D. [Centre de Secours Principal de Rambouillet, 78 (France)
1998-07-01
The purpose of this article is to answer this question: what does optimization mean in the frame of an assistance operation. Two points have been developed: the first one is devoted to a broad training and sensitizing for the persons susceptible to participate to these interventions, the second one is the preparation of operations: it is possible to develop optimization from information feedback. (N.C.)
Operator assisted optimization of sludge dewatering
DEFF Research Database (Denmark)
Grüttner, Henrik
1991-01-01
On a municipal wastewater treatment plant using a decanter-centrifuge for dewatering of anaerobic digested sludge an operator assisting system for sludge dewatering was developed. The system is based on a database used to collect data on sludge properties and operational conditions which is added...... by the operator. By graphical presentation and an advisory service these data are used to support the operator in his dewatering operations and to secure a running optimization of the sludge dewatering. Evaluations show that this system is a useful tool for data collection and presentation and that the data...... collected seem to reflect the actual situation at the plant. In the future such systems are expected to be used as tools for education of operators, transfer of knowledge from one operator to another and for a continuous optimization of dewatering operations. (A)...
DEFF Research Database (Denmark)
Baldin, Andrea; Bille, Trine; Ellero, Andrea
The implementation of Revenue Management (RM) techniques in non profit performing arts organizations presents new challenges compared to other sectors, such as transportion or hospitality industries, in which these techniques are more consolidated. Indeed, performing arts organizations...... are characterized by a multi-objective function that is not solely limited to revenue. On the one hand, theatres aim to increase revenue from box office as a consequence of the systematic reduction of public funds; on the other hand they pursue the objective to increase its attendance. A common practice by theatres...... is to incentive the customers to discriminate among themselves according to their reservation price, offering a schedule of different prices corresponding to different seats in the venue. In this context, price and allocation of the theatre seating area are decision variables that allow theatre managers to manage...
Rearrangement invariant optimal range for Hardy type operators
Soria, Javier; Tradacete, Pedro
2013-01-01
We characterize, in the context of rearrangement invariant spaces, the optimal range space for a class of monotone operators related to the Hardy operator. The connection between optimal range and optimal domain for these operators is carefully analyzed.
OPTIMAL OPERATIONAL CONTROL OF INTERCEPTOR SEWER SYSTEM
Institute of Scientific and Technical Information of China (English)
无
2002-01-01
In this paper, a mathematical model was built up to solve the problem of optimal operational control by analysing the factors on an interceptor sewer system and a Fortran program was produced for this model. This paper shows that the optimal control states can be determined by working out the optimal flow rates by means of Linear Programming (LP). The result is very sensitive to interception points and the concentration weight coefficients over time. The result further highlights some practical applications for the existing sewer systems or the sewer systems under design.
Institute of Scientific and Technical Information of China (English)
Zhao Fei
2011-01-01
January to April in 2011,the textile machinery industry saw total profits of 1.861 billion yuan,increasing 45.19% year on year;the overall operating performance of the industry presents a stable development momentum with a decline in gross profits.From January to May of this year,the cumulative total import and export value amounts to 3.209 billion USD,rising 51.39% over the same period
Directory of Open Access Journals (Sweden)
Moein parastegari
2015-03-01
Full Text Available Optimal operation and bidding strategy of renewable units are two important problems of the restructured power market. In this paper, a new method for the joint operation of wind, photovoltaic and pump-storage units in day ahead power market is studied to increase the profit of joint units. In this study, artificial neural network is used to predict the wind power generation of wind farms. Since, there are uncertainties in energy and reserve prices, wind and photovoltaic power generation, the optimal operation of joint units can be modeled as a stochastic optimization problem. For this purpose, uncertainties of parameters are modeled by scenario tree method. The performance of the proposed method is evaluated on the renewable energy resources (wind farms, photovoltaic and pump-storage units of the modified IEEE 118 bus test system. Results of the proposed joint operation of renewable resources confirm that the value of expected profit increases in comparison with uncoordinated operation (UO of units.
Communication Strategy of a Non-Profit Organization
Crhová, Kateřina
2014-01-01
The main goal of the diploma thesis is to analyze the communication strategy of the non-profit organization Otevřená OKNA, z. ú. including its assessment, and to suggest an optimization of the communication strategy based on this analysis. The real possibilities of non-profit organizations and the environment in which it is located and operates were taken into account. The theoretical part defines and formulates the fundamental findings related to the non-profit sector, non-profit organizatio...
DEFF Research Database (Denmark)
Lund, Henrik; Salgi, Georges; Elmegaard, Brian;
2009-01-01
on electricity spot markets by storing energy when electricity prices are low and producing electricity when prices are high. In order to make a profit on such markets, CAES plant operators have to identify proper strategies to decide when to sell and when to buy electricity. This paper describes three...... plants will not be able to achieve such optimal operation, since the fluctuations of spot market prices in the coming hours and days are not known. Consequently, two simple practical strategies have been identified and compared to the results of the optimal strategy. This comparison shows that...... independent computer-based methodologies which may be used for identifying the optimal operation strategy for a given CAES plant, on a given spot market and in a given year. The optimal strategy is identified as the one which provides the best business-economic net earnings for the plant. In practice, CAES...
Systematic Methodology for Reproducible Optimizing Batch Operation
DEFF Research Database (Denmark)
Bonné, Dennis; Jørgensen, Sten Bay
2006-01-01
This contribution presents a systematic methodology for rapid acquirement of discrete-time state space model representations of batch processes based on their historical operation data. These state space models are parsimoniously parameterized as a set of local, interdependent models. The present....... This controller may also be used for Optimizing control. The modeling and control performance is demonstrated on a fed-batch protein cultivation example. The presented methodologies lend themselves directly for application as Process Analytical Technologies (PAT)....
PROFIT TAX OR INCOME TAX? OPTIONS FOR FISCAL OPTIMIZATION OF ROMANIAN SMALL COMPANIES
Directory of Open Access Journals (Sweden)
Doina Pacurari
2014-01-01
Full Text Available Entrepreneurs usually seek for solutions to reduce their tax burden. We can speak about tax optimization as long as these solutions are in accordance with the law; if they are not, they obviously fall into the area of fiscal fraud. This paper addresses the issue of taxation applicable to the Romanian micro-enterprises. These are small entities that fulfil certain conditions regarding total turnover, equity and domain of activity. Although the provisions applying to micro-enterprise taxation were elaborated, among others, with the intention to reduce tax evasion, they also allow the micro-enterprises with losses to avoid tax payment. In a country with low purchasing power and a great number of taxes and fees like Romania, the entrepreneurs are tempted to use any kind of method to reduce the payments due to the state budget. The micro-enterprise owners make no exception in this matter.
Pando, V.; García-Laguna, J.; San-José, L. A.
2012-11-01
In this article, we integrate a non-linear holding cost with a stock-dependent demand rate in a maximising profit per unit time model, extending several inventory models studied by other authors. After giving the mathematical formulation of the inventory system, we prove the existence and uniqueness of the optimal policy. Relying on this result, we can obtain the optimal solution using different numerical algorithms. Moreover, we provide a necessary and sufficient condition to determine whether a system is profitable, and we establish a rule to check when a given order quantity is the optimal lot size of the inventory model. The results are illustrated through numerical examples and the sensitivity of the optimal solution with respect to changes in some values of the parameters is assessed.
Directory of Open Access Journals (Sweden)
Hamidah Hamidah
2016-04-01
Full Text Available The purpose of this study is to know the effect of profitability, liquidity, sales growth, operating leverage and tangibility on capital structure: evidence from manufacture firm listed on Indonesia Stock Exchange in 2011-2014. The sample using in this study is 41 companies. The research model in this study employs panel data analysis (unbalanced panel with fixed effect approach. The result show that profitability and liquidity have negative and significant effect on capital structure. Sales growth and operating leverage have positive but not significant effect on capital structure. Tangibility have negative and not significant effect on capital structure.
Optimizing Integrated Terminal Airspace Operations Under Uncertainty
Bosson, Christabelle; Xue, Min; Zelinski, Shannon
2014-01-01
In the terminal airspace, integrated departures and arrivals have the potential to increase operations efficiency. Recent research has developed geneticalgorithm- based schedulers for integrated arrival and departure operations under uncertainty. This paper presents an alternate method using a machine jobshop scheduling formulation to model the integrated airspace operations. A multistage stochastic programming approach is chosen to formulate the problem and candidate solutions are obtained by solving sample average approximation problems with finite sample size. Because approximate solutions are computed, the proposed algorithm incorporates the computation of statistical bounds to estimate the optimality of the candidate solutions. A proof-ofconcept study is conducted on a baseline implementation of a simple problem considering a fleet mix of 14 aircraft evolving in a model of the Los Angeles terminal airspace. A more thorough statistical analysis is also performed to evaluate the impact of the number of scenarios considered in the sampled problem. To handle extensive sampling computations, a multithreading technique is introduced.
Optimization of Operating Systems towards Green Computing
Directory of Open Access Journals (Sweden)
Appasami Govindasamy
2011-01-01
Full Text Available Green Computing is one of the emerging computing technology in the field of computer science engineering and technology to provide Green Information Technology (Green IT. It is mainly used to protect environment, optimize energy consumption and keeps green environment. Green computing also refers to environmentally sustainable computing. In recent years, companies in the computer industry have come to realize that going green is in their best interest, both in terms of public relations and reduced costs. Information and communication technology (ICT has now become an important department for the success of any organization. Making IT “Green” can not only save money but help save our world by making it a better place through reducing and/or eliminating wasteful practices. In this paper we focus on green computing by optimizing operating systems and scheduling of hardware resources. The objectives of the green computing are human power, electrical energy, time and cost reduction with out polluting the environment while developing the software. Operating System (OS Optimization is very important for Green computing, because it is bridge for both hardware components and Application Soft wares. The important Steps for green computing user and energy efficient usage are also discussed in this paper.
An Optimization Study of Hot Stamping Operation
Ghoo, Bonyoung; Umezu, Yasuyoshi; Watanabe, Yuko; Ma, Ninshu; Averill, Ron
2010-06-01
In the present study, 3-dimensional finite element analyses for hot-stamping processes of Audi B-pillar product are conducted using JSTAMP/NV and HEEDS. Special attention is paid to the optimization of simulation technology coupling with thermal-mechanical formulations. Numerical simulation based on FEM technology and optimization design using the hybrid adaptive SHERPA algorithm are applied to hot stamping operation to improve productivity. The robustness of the SHERPA algorithm is found through the results of the benchmark example. The SHERPA algorithm is shown to be far superior to the GA (Genetic Algorithm) in terms of efficiency, whose calculation time is about 7 times faster than that of the GA. The SHERPA algorithm could show high performance in a large scale problem having complicated design space and long calculation time.
McCue, Michael J.
2007-01-01
Context: National benchmark data for 2002 indicate that large rural for-profit hospitals have a median cash flow margin of 19.5% compared to 9.2% for their nonprofit counterparts. Purpose: This study aims to gain insight regarding the driving factors behind the high cash flow performance of large rural for-profit hospitals. Methods: Using 3 annual…
DEFF Research Database (Denmark)
Bingley, Paul; Westergård-Nielsen, Niels Chr.
2004-01-01
of the firm. Here we follow the population of 7118 medium-to-large sized private sector Danish firms over the period 1992-95. In an instrumental variables framework, we use changes in the personnel composition of different firms operating in the same local labour market to provide exogenous identifying...... personnel structure variation. It is found that personnel policy is strongly related to economic performance. At the margin, more hires are associated with lower profit, and more separations with higher profit. For the average firm, one new job, all else equal, is associated with ?2680 (2000 prices) lower...... annual profit. Higher wage level and lower wage growth is associated with higher profit. A workforce that has less tenure, all else equal, is more profitable....
Operational Optimization in Port Container Terminals
DEFF Research Database (Denmark)
As a result of the significant increase in worldwide containerized transportation the development of efficient handling systems in marine terminals has become very important for port competitiveness. In order to optimize the productivity the total handling time for containers in the terminal must...... be minimized. An overview of the different operational problems in port container terminals is presented and an aggregated model and solution approach is shown. Next, there will be focused on the yard storage problem and a mathematical formulation and solution proposals will be presented....
Optimization of Train Trip Package Operation Scheme
Directory of Open Access Journals (Sweden)
Lu Tong
2015-01-01
Full Text Available Train trip package transportation is an advanced form of railway freight transportation, realized by a specialized train which has fixed stations, fixed time, and fixed path. Train trip package transportation has lots of advantages, such as large volume, long distance, high speed, simple forms of organization, and high margin, so it has become the main way of railway freight transportation. This paper firstly analyzes the related factors of train trip package transportation from its organizational forms and characteristics. Then an optimization model for train trip package transportation is established to provide optimum operation schemes. The proposed model is solved by the genetic algorithm. At last, the paper tests the model on the basis of the data of 8 regions. The results show that the proposed method is feasible for solving operation scheme issues of train trip package.
Profitability Versus Construction Equipment Maintenance
2010-05-01
E7(/(3+21(180%(5 ,QFOXGHDUHDFRGH XX-05-2010 Master’s Thesis DEC 2009 - MAY 2010 Profitability Versus Construction Equipment Maintenance...optimization of a perceived profit . This project recommends a decision support model that can be used by private and public entities alike to determine the...best fir acquisition method between rent-lease-buy and guidance for profitability optimization. Methods of life cycle cost estimating and decision
Production optimization of remotely operated gas wells
Energy Technology Data Exchange (ETDEWEB)
Juell, Aleksander
2012-07-01
From the introduction: The Remote Operations in Oklahoma Intended for Education (ROOKIE) project is a remote field laboratory constructed as a part of this research project. ROOKIE was initiated to provide data in research on production optimization of low productivity gas wells. In addition to this, ROOKIE is used as a teaching tool. Much of the remote operations technology used in the ROOKIE project has been used by the industry for several decades. The first use of remote data acquisition in Oklahoma was in 1989, as described by Luppens [7]. Even though this, for the most part, is old technology, the ROOKIE project is the first remote operations project set up with research and teaching as the main focus. This chapter will discuss the process of establishing the remote field laboratory and the data storage facilities. Results from the project will also be discussed. All testing, instrumentation installation, and modifications to the wells discussed in this chapter was performed by the author. The communication system between the well and NTNU, and the storage database was installed and configured by the author.(Author)
Directory of Open Access Journals (Sweden)
Chenghong Gu
2015-12-01
Full Text Available This paper develops a discrete operation optimization model for combined heat and powers (CHPs in deregulated energy markets to maximize owners’ profits, where energy price forecasting is included. First, a single input and multi-output (SIMO model for typical CHPs is established, considering the varying ratio between heat and electricity outputs at different loading levels. Then, the energy prices are forecasted with a gray forecasting model and revised in real-time based on the actual prices by using the least squares method. At last, a discrete optimization model and corresponding dynamic programming algorithm are developed to design the optimal operation strategies for CHPs in real-time. Based on the forecasted prices, the potential operating strategy which may produce the maximum profits is pre-developed. Dynamic modification is then conducted to adjust the pre-developed operating strategy after the actual prices are known. The proposed method is implemented on a 1 MW CHP on a typical day. Results show the optimized profits comply well with those derived from real-time prices after considering dynamic modification process.
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...... to be used at the balancing stage. Linear decision rules are seen as a natural approach to model and optimize the real-time operation policy. These allow enhancing profits from balancing markets based on updated information on prices and wind power generation. Our integrated strategies for WF...
Influence of Design Margin on Operation Optimization and Control Performance of Chemical Processes
Institute of Scientific and Technical Information of China (English)
许锋; 蒋慧蓉; 王锐; 罗雄麟
2014-01-01
Operation optimization is an effective method to explore potential economic benefits for existing plants. The maximum potential benefit from operation optimization is determined by the distances between current operat-ing point and process constraints, which is related to the margins of design variables. Because of various distur-bances in chemical processes, some distances must be reserved for fluctuations of process variables and the opti-mum operating point is not on some process constraints. Thus the benefit of steady-state optimization can not be fully achieved while that of dynamic optimization can be really achieved. In this study, the steady-state optimization and dynamic optimization are used, and the potential benefit is divided into achievable benefit for profit and un-achievable benefit for control. The fluid catalytic cracking unit (FCCU) is used for case study. With the analysis on how the margins of design variables influence the economic benefit and control performance, the bottlenecks of process design are found and appropriate control structure can be selected.
DEFF Research Database (Denmark)
Hu, Weihao; Chen, Zhe; Bak-Jensen, Birgitte
2010-01-01
Since the hourly spot market price is available one day ahead, the price could be transferred to the consumers and they may have some motivations to install an energy storage system in order to save their energy costs. This paper presents an optimal operation strategy for a battery energy storage...... system (BESS) in relation to the real-time electricity price in order to achieve the maximum profits of the BESS. The western Danish power system, which is currently the grid area in the world that has the largest share of wind power in its generation profiles and may represent the future of electricity...
Optimized green operation of LTE networks in the presence of multiple electricity providers
Ghazzai, Hakim
2012-12-01
Energy efficiency aspects in cellular networks can significantly contribute to the reduction of greenhouse gas emissions and help to save the environment. The base station (BS) sleeping strategy has become a well-known technique to achieve energy savings by switching off redundant BSs mainly for lightly loaded networks. Besides, introducing renewable energies as alternative power sources becomes a real challenge to network operators. In this paper, we propose a method that reduces the energy consumption of BSs by not only shutting down underutilized BSs but also by optimizing the amounts of energy procured from different retailers (Renewable energy and electricity retailers). We formulate an optimization problem that leads to the maximization of the profit of a Long-Term Evolution (LTE) cellular operator, and at the same time to the minimization of CO2 emissions in green wireless cellular networks without affecting the desired Quality of Service. © 2012 IEEE.
Mapping the Profit Motive: The Distinct Geography and Demography of For-Profit Charter Schools
Robertson, W. Brett
2015-01-01
For-profit charter schools represent a controversial new market-based education reform (Garcia, Barber, & Molnar, 2009; Conn, 2002). This essay explores how schools operated by for-profit corporations differ from those operated by non-profit organizations. Specifically, do for-profit charter schools locate in demographically distinct areas and…
Weinstein, Margery
2012-01-01
Preparing employees for the immediate work in front of them is a challenge. While most companies are still mastering effectively training their own workforce, some, such as "Training" magazine Top 10 Hall of Famer The Ritz-Carlton Hotel Company, have set up for-profit academies open to the public. When Ritz-Carlton won the national Malcolm…
Optimization of wastewater treatment plant operation for greenhouse gas mitigation.
Kim, Dongwook; Bowen, James D; Ozelkan, Ertunga C
2015-11-01
This study deals with the determination of optimal operation of a wastewater treatment system for minimizing greenhouse gas emissions, operating costs, and pollution loads in the effluent. To do this, an integrated performance index that includes three objectives was established to assess system performance. The ASMN_G model was used to perform system optimization aimed at determining a set of operational parameters that can satisfy three different objectives. The complex nonlinear optimization problem was simulated using the Nelder-Mead Simplex optimization algorithm. A sensitivity analysis was performed to identify influential operational parameters on system performance. The results obtained from the optimization simulations for six scenarios demonstrated that there are apparent trade-offs among the three conflicting objectives. The best optimized system simultaneously reduced greenhouse gas emissions by 31%, reduced operating cost by 11%, and improved effluent quality by 2% compared to the base case operation.
Research on Optimization Operation of Urban Gas Pipeline Network
Institute of Scientific and Technical Information of China (English)
田一梅; 迟海燕; 李鸿; 周颖
2003-01-01
The optimization operation of gas pipeline network is investigated in this paper. Based on the theories of system optimization and the multi-object decision, a mathematical model about the multi-object optimization operation of gas pipeline network is established, in line with the demand of urban gas pipeline network operation. At the same time, an effective solution of the mathematical model is presented. A calculating software about optimization operation is compiled, coupling the actual operation of gas pipeline network. It can be applied to the operation of the gas pipeline network. The software was examined by real examples. The results indicated that 2.13%00 energy consumption and 3.12%oo gas supply cost can be reduced through optimization operation.
The Optimal Operation Criteria for a Gas Turbine Cogeneration System
Directory of Open Access Journals (Sweden)
Atsushi Akisawa
2009-04-01
Full Text Available The study demonstrated the optimal operation criteria of a gas turbine cogeneration system based on the analytical solution of a linear programming model. The optimal operation criteria gave the combination of equipment to supply electricity and steam with the minimum energy cost using the energy prices and the performance of equipment. By the comparison with a detailed optimization result of an existing cogeneration plant, it was shown that the optimal operation criteria successfully provided a direction for the system operation under the condition where the electric power output of the gas turbine was less than the capacity
Directory of Open Access Journals (Sweden)
Borja Amor-Tapia
2014-01-01
Full Text Available In this paper we examine how the relative position of a firm's Return on Equity (ROE in industries affects the predictability of the next-year ROE levels, and the ROE changes from year to year. Using Nissim and Penman breakdown into operating and financing drivers, the significant role of the industry factor is established, although changes in signs suggest subtle non-linear relations in the drivers. Our study avoids problems originating from negative signs by analyzing sorts and by making new regressions with disaggregated second-order drivers by signs. This way, our results provide evidence of some different patterns in the influence of the first-level drivers of ROE (the operating factor and the financing factor, and the second-level drivers (profit margin, asset turnover, leverage and return spread on future profitability, depending on the industry spread. The results on the role of contextual factors to improve the estimation of future profitability remain consistent for small and large firms, although adding some nuances.
Classification and uptake of reservoir operation optimization methods
Dobson, Barnaby; Pianosi, Francesca; Wagener, Thorsten
2016-04-01
Reservoir operation optimization algorithms aim to improve the quality of reservoir release and transfer decisions. They achieve this by creating and optimizing the reservoir operating policy; a function that returns decisions based on the current system state. A range of mathematical optimization algorithms and techniques has been applied to the reservoir operation problem of policy optimization. In this work, we propose a classification of reservoir optimization approaches by focusing on the formulation of the water management problem rather than the optimization algorithm type. We believe that decision makers and operators will find it easier to navigate a classification system based on the problem characteristics, something they can clearly define, rather than the optimization algorithm. Part of this study includes an investigation regarding the extent of algorithm uptake and the possible reasons that limit real world application.
Modeling and optimization of laser cutting operations
Directory of Open Access Journals (Sweden)
Gadallah Mohamed Hassan
2015-01-01
Full Text Available Laser beam cutting is one important nontraditional machining process. This paper optimizes the parameters of laser beam cutting parameters of stainless steel (316L considering the effect of input parameters such as power, oxygen pressure, frequency and cutting speed. Statistical design of experiments is carried in three different levels and process responses such as average kerf taper (Ta, surface roughness (Ra and heat affected zones are measured accordingly. A response surface model is developed as a function of the process parameters. Responses predicted by the models (as per Taguchi’s L27OA are employed to search for an optimal combination to achieve desired process yield. Response Surface Models (RSMs are developed for mean responses, S/N ratio, and standard deviation of responses. Optimization models are formulated as single objective optimization problem subject to process constraints. Models are formulated based on Analysis of Variance (ANOVA and optimized using Matlab developed environment. Optimum solutions are compared with Taguchi Methodology results. As such, practicing engineers have means to model, analyze and optimize nontraditional machining processes. Validation experiments are carried to verify the developed models with success.
THE ANALYSIS OF PROFITABILITY INDICATORS
Directory of Open Access Journals (Sweden)
SUCIU GHEORGHE
2013-08-01
Full Text Available The analysis of profitability indicators is an activity that should preoccupy all companies. Profitabilitydoes not mean only obtaining profit. A company is competitive if the ownership equity grows (the shareholders’money, the company has a profit that is comparable to that of other companies from the same area of activity,has a positive cash flow and the employees are satisfied with their salaries. Multiple indicators are used tomeasure performance: profit, commercial, economic, financial, investment rate of return, breakeven point,economic value added, net operating result.
Service Operations Optimization: Recent Development in Supply Chain Management
Bin Shen
2015-01-01
Services are the key of success in operation management. Designing the effective strategies by optimization techniques is the fundamental and important condition for performance increase in service operations (SOs) management. In this paper, we mainly focus on investigating SOs optimization in the areas of supply chain management, which create the greatest business values. Specifically, we study the recent development of SOs optimization associated with supply chain by categorizing them into ...
THE PERSISTENCE OF INSURERS PROFITABILITY
Directory of Open Access Journals (Sweden)
Maja Pervan
2013-02-01
Full Text Available Most of the academic researches have analyzed the persistence of profit for the manufacturing and (non-financial services sector. These studies were mainly conducted in advance market economies. In order to shed some light on the issue of persistence in corporate rates of return, this research aims to examine the persistence of profitability of financial entities i.e. non-life insurance companies operating in an emerging market economy, Croatia. In order to determine persistence of insurers’ profitability, a Markov Chains stochastic process is applied on the profitability classes that were formulated based on the changes of insurers’ ROA (return on assets indicator during the period from 2002 to 2011. The empirical results showed that profit persistence was more likely to occur within moderate profit classes/states.
Optimization Criteria of Power Transformer Operation
Directory of Open Access Journals (Sweden)
A. A. Gonchar
2006-01-01
Full Text Available It has been shown that minimum losses in active power of a power transformer do not correspond to its maximum efficiency. For a transformer being operated there are no so called «zones of its economical operation». In this case strictly specified value of active power losses corresponds to a particular current of the winding.
Optimal operation of water distribution networks under local pipe failures
Institute of Scientific and Technical Information of China (English)
TIAN Yi-mei; G.Y.FU; CHI Hai-yan; LIU Ye
2007-01-01
The optimal operation of water distribution networks under local pipe failures, such as water main breaks, was proposed.Based on a hydraulic analysis and a simulation of water distribution networks, a macroscopic model for a network under a local pipe failure was established by the statistical regression. After the operation objectives under a local pipe failure were determined, the optimal operation model was developed and solved by the genetic algorithm. The program was developed and examined by a city distribution network. The optimal operation alternative shows that the electricity cost is saved approximately 11%, the income of the water corporation is increased approximately 5%, and the pressure in the water distribution network is distributed evenly to ensure the network safe operation. Therefore, the proposed method for optimal operation under local pipe failure is feasible and cost-effective.
Deterministic operations research models and methods in linear optimization
Rader, David J
2013-01-01
Uniquely blends mathematical theory and algorithm design for understanding and modeling real-world problems Optimization modeling and algorithms are key components to problem-solving across various fields of research, from operations research and mathematics to computer science and engineering. Addressing the importance of the algorithm design process. Deterministic Operations Research focuses on the design of solution methods for both continuous and discrete linear optimization problems. The result is a clear-cut resource for understanding three cornerstones of deterministic operations resear
Operations Optimization of Hybrid Energy Systems under Variable Markets
Energy Technology Data Exchange (ETDEWEB)
Chen, Jun; Garcia, Humberto E.
2016-07-01
Hybrid energy systems (HES) have been proposed to be an important element to enable increasing penetration of clean energy. This paper investigates the operations flexibility of HES, and develops a methodology for operations optimization to maximize its economic value based on predicted renewable generation and market information. The proposed operations optimizer allows systematic control of energy conversion for maximal economic value, and is illustrated by numerical results.
Towards optimal saving in membrane operation
Ven, van de Wilhelmus Johannes Cornelis
2008-01-01
This work aims at the development of methods for fingerprinting filtration processes. These fingerprints can potentially be used to optimize the filtration performance of large scale dead-end hollow fiber ultrafiltration systems that are used nowadays in the production of drinking water. The develop
Optimizing emergency department front-end operations.
Wiler, Jennifer L; Gentle, Christopher; Halfpenny, James M; Heins, Alan; Mehrotra, Abhi; Mikhail, Michael G; Fite, Diana
2010-02-01
As administrators evaluate potential approaches to improve cost, quality, and throughput efficiencies in the emergency department (ED), "front-end" operations become an important area of focus. Interventions such as immediate bedding, bedside registration, advanced triage (triage-based care) protocols, physician/practitioner at triage, dedicated "fast track" service line, tracking systems and whiteboards, wireless communication devices, kiosk self check-in, and personal health record technology ("smart cards") have been offered as potential solutions to streamline the front-end processing of ED patients, which becomes crucial during periods of full capacity, crowding, and surges. Although each of these operational improvement strategies has been described in the lay literature, various reports exist in the academic literature about their effect on front-end operations. In this report, we present a review of the current body of academic literature, with the goal of identifying select high-impact front-end operational improvement solutions.
A simple technique to increase profits in wood products marketing
George B. Harpole
1971-01-01
Mathematical models can be used to solve quickly some simple day-to-day marketing problems. This note explains how a sawmill production manager, who has an essentially fixed-capacity mill, can solve several optimization problems by using pencil and paper, a forecast of market prices, and a simple algorithm. One such problem is to maximize profits in an operating period...
UMTS network planning, optimization, and inter-operation with GSM
Rahnema, Moe
2008-01-01
UMTS Network Planning, Optimization, and Inter-Operation with GSM is an accessible, one-stop reference to help engineers effectively reduce the time and costs involved in UMTS deployment and optimization. Rahnema includes detailed coverage from both a theoretical and practical perspective on the planning and optimization aspects of UMTS, and a number of other new techniques to help operators get the most out of their networks. Provides an end-to-end perspective, from network design to optimizationIncorporates the hands-on experiences of numerous researchersSingle
Operational Readiness Simulator: Optimizing Operational Availability Using a Virtual Environment
Directory of Open Access Journals (Sweden)
Shaun Horning
2012-01-01
Full Text Available The maintenance and logistics systems that support aircraft fleets are complex and often very integrated. The complexity of these systems makes it difficult to assess the impact of events that affect operational capability, to identify the need for resources that can affect aircraft availability, or to assess the impact and potential benefits of the system and procedural changes. This problem is further complicated by the adoption of condition-based maintenance approaches resulting in dynamic maintenance planning as maintenance tasks are condition directed instead of scheduled or usage based. A proof of concept prototype for an aircraft operational readiness simulator (OR-SIM has been developed for the Canadian Forces CH-146 Griffon helicopter. The simulator provides a synthetic environment to forecast and assess the ability of a fleet, squadron, or aircraft to achieve desired flying rates and the capability of the sustainment systems to respond to the resultant demands. The prototype was used to assess several typical scenarios including adjustment of preventative maintenance schedules including impact of condition-based maintenance, variation of the annual flying rate, and investigation of deployment options. This paper provides an overview of the OR-SIM concept, prototype model, and sample investigations and a discussion of the benefits of such an operational readiness simulator.
Optimizing Traffic Operation in Designing Specific Upgrades
Directory of Open Access Journals (Sweden)
Ebrahim Sangsefidi
2015-01-01
Full Text Available Transport forms one of the primary needs in all categories of the population in modern society; it is of paramount concern for traffic engineers, transport planners, and policy makers to understand and evaluate the quality of service being provided by the transport facilities designed by them. This paper presents an investigation in profile geometric design and traffic flow operation on two-lane two-way highways and provides analyses that will help in a better understanding of traffic operation on these facilities to select the optimum profile configuration. The effects of influencing parameters consisting of grade, length of grade, traffic composition, and traffic volume are evaluated and finally a systematic procedure to evaluate flow rate under the base condition is presented. Finally, based on these achievements an algorithm is introduced to select optimum Finished Ground of profile view. Results show that the percentage of heavy vehicles has a contributing effect on traffic operation so that the optimum profile configuration is incredibly affected by this factor. Source data have been obtained from Highway Capacity Manual (HCM as a pioneer document in respect of quantifying the concept of capacity for a transport facility.
Optimization principle of operating parameters of heat exchanger by using CFD simulation
Mičieta, Jozef; Jiří, Vondál; Jandačka, Jozef; Lenhard, Richard
2016-03-01
Design of effective heat transfer devices and minimizing costs are desired sections in industry and they are important for both engineers and users due to the wide-scale use of heat exchangers. Traditional approach to design is based on iterative process in which is gradually changed design parameters, until a satisfactory solution is achieved. The design process of the heat exchanger is very dependent on the experience of the engineer, thereby the use of computational software is a major advantage in view of time. Determination of operating parameters of the heat exchanger and the subsequent estimation of operating costs have a major impact on the expected profitability of the device. There are on the one hand the material and production costs, which are immediately reflected in the cost of device. But on the other hand, there are somewhat hidden costs in view of economic operation of the heat exchanger. The economic balance of operation significantly affects the technical solution and accompanies the design of the heat exchanger since its inception. Therefore, there is important not underestimate the choice of operating parameters. The article describes an optimization procedure for choice of cost-effective operational parameters for a simple double pipe heat exchanger by using CFD software and the subsequent proposal to modify its design for more economical operation.
Optimization principle of operating parameters of heat exchanger by using CFD simulation
Directory of Open Access Journals (Sweden)
Mičieta Jozef
2016-01-01
Full Text Available Design of effective heat transfer devices and minimizing costs are desired sections in industry and they are important for both engineers and users due to the wide-scale use of heat exchangers. Traditional approach to design is based on iterative process in which is gradually changed design parameters, until a satisfactory solution is achieved. The design process of the heat exchanger is very dependent on the experience of the engineer, thereby the use of computational software is a major advantage in view of time. Determination of operating parameters of the heat exchanger and the subsequent estimation of operating costs have a major impact on the expected profitability of the device. There are on the one hand the material and production costs, which are immediately reflected in the cost of device. But on the other hand, there are somewhat hidden costs in view of economic operation of the heat exchanger. The economic balance of operation significantly affects the technical solution and accompanies the design of the heat exchanger since its inception. Therefore, there is important not underestimate the choice of operating parameters. The article describes an optimization procedure for choice of cost-effective operational parameters for a simple double pipe heat exchanger by using CFD software and the subsequent proposal to modify its design for more economical operation.
Synergy optimization and operation management on syndicate complementary knowledge cooperation
Tu, Kai-Jan
2014-10-01
The number of multi enterprises knowledge cooperation has grown steadily, as a result of global innovation competitions. I have conducted research based on optimization and operation studies in this article, and gained the conclusion that synergy management is effective means to break through various management barriers and solve cooperation's chaotic systems. Enterprises must communicate system vision and access complementary knowledge. These are crucial considerations for enterprises to exert their optimization and operation knowledge cooperation synergy to meet global marketing challenges.
Optimal scope of supply chain network & operations design
Ma, N.
2014-01-01
The increasingly complex supply chain networks and operations call for the development of decision support systems and optimization techniques that take a holistic view of supply chain issues and provide support for integrated decision-making. The economic impacts of optimized supply chain are signi
Optimal scope of supply chain network & operations design
Ma, N.
2014-01-01
The increasingly complex supply chain networks and operations call for the development of decision support systems and optimization techniques that take a holistic view of supply chain issues and provide support for integrated decision-making. The economic impacts of optimized supply chain are signi
Concrete Plant Operations Optimization Using Combined Simulation and Genetic Algorithms
Cao, Ming; Lu, Ming; Zhang, Jian-Ping
2004-01-01
This work presents a new approach for concrete plant operations optimization by combining a ready mixed concrete (RMC) production simulation tool (called HKCONSIM) with a genetic algorithm (GA) based optimization procedure. A revamped HKCONSIM computer system can be used to automate the simulation m
Concrete Plant Operations Optimization Using Combined Simulation and Genetic Algorithms
Cao, Ming; Lu, Ming; Zhang, Jian-Ping
2004-01-01
This work presents a new approach for concrete plant operations optimization by combining a ready mixed concrete (RMC) production simulation tool (called HKCONSIM) with a genetic algorithm (GA) based optimization procedure. A revamped HKCONSIM computer system can be used to automate the simulation m
Optimization of operational aircraft parameters Reducing Noise Emission
Abdallah, Lina; Khardi, Salah
2008-01-01
The objective of this paper is to develop a model and a minimization method to provide flight path optimums reducing aircraft noise in the vicinity of airports. Optimization algorithm has solved a complex optimal control problem, and generates flight paths minimizing aircraft noise levels. Operational and safety constraints have been considered and their limits satisfied. Results are here presented and discussed.
Concrete Plant Operations Optimization Using Combined Simulation and Genetic Algorithms
Cao, Ming; Lu, Ming; Zhang, Jian-Ping
2004-01-01
This work presents a new approach for concrete plant operations optimization by combining a ready mixed concrete (RMC) production simulation tool (called HKCONSIM) with a genetic algorithm (GA) based optimization procedure. A revamped HKCONSIM computer system can be used to automate the simulation
Model-based Optimization of Oil Recovery: Robust Operational Strategies
Van Essen, G.M.
2015-01-01
The process of depleting an oil reservoir can be poured into an optimal control problem with the objective to maximize economic performance over the life of the ﬁeld. Despite its large potential, life-cycle optimization has not yet found its way into operational environments. The objective of this t
Particle Swarm Optimization with Genetic Operators for Vehicle Routing Problem
Directory of Open Access Journals (Sweden)
P. V. PURANIK
2012-07-01
Full Text Available Vehicle Routing Problem (VRP is to find shortest route thereby minimizing total cost. VRP is a NP-hard and Combinatorial optimization problem. Such problems increase exponentially with the problem size. Various derivative based optimization techniques are employed for optimization. Derivative based optimization techniques are difficult to evaluate. Therefore parallel search algorithm emerged to solve VRP. In this work, a particle swarm optimization (PSO algorithm and Genetic algorithm (GA with crossover and mutation operator are applied to two typical functions to deal with the problem of VRP efficiently using MATLAB software. Before solving VRP, optimization of functions using PSO and GA are checked. In this paper capacitate VRP with time window (CVRPTW is proposed. The computational result shows generation of input for VRP, optimization of Rastrigin function, Rosenbrock function using PSO and GA.
Vector optimization and monotone operators via convex duality recent advances
Grad, Sorin-Mihai
2014-01-01
This book investigates several duality approaches for vector optimization problems, while also comparing them. Special attention is paid to duality for linear vector optimization problems, for which a vector dual that avoids the shortcomings of the classical ones is proposed. Moreover, the book addresses different efficiency concepts for vector optimization problems. Among the problems that appear when the framework is generalized by considering set-valued functions, an increasing interest is generated by those involving monotone operators, especially now that new methods for approaching them by means of convex analysis have been developed. Following this path, the book provides several results on different properties of sums of monotone operators.
Nickel-Cadmium Battery Operation Management Optimization Using Robust Design
Blosiu, Julian O.; Deligiannis, Frank; DiStefano, Salvador
1996-01-01
In recent years following several spacecraft battery anomalies, it was determined that managing the operational factors of NASA flight NiCd rechargeable battery was very important in order to maintain space flight battery nominal performance. The optimization of existing flight battery operational performance was viewed as something new for a Taguchi Methods application.
Service Operations Optimization: Recent Development in Supply Chain Management
Directory of Open Access Journals (Sweden)
Bin Shen
2015-01-01
Full Text Available Services are the key of success in operation management. Designing the effective strategies by optimization techniques is the fundamental and important condition for performance increase in service operations (SOs management. In this paper, we mainly focus on investigating SOs optimization in the areas of supply chain management, which create the greatest business values. Specifically, we study the recent development of SOs optimization associated with supply chain by categorizing them into four different industries (i.e., e-commerce industry, consumer service industry, public sector, and fashion industry and four various SOs features (i.e., advertising, channel coordination, pricing, and inventory. Moreover, we conduct the technical review on the stylish industries/topics and typical optimization models. The classical optimization approaches for SOs management in supply chain are presented. The managerial implications of SOs in supply chain are discussed.
Optimal modes of operation of two idealized magnetohydrodynamic devices
Energy Technology Data Exchange (ETDEWEB)
Okulov, N.A.
1984-01-01
A conduction channel and a conduction cylinder, idealized devices, which model the operation of conduction magnetohydrodynamic (MGD) generators (pump) and magnetohydrodynamic propulsion devices, are examined. It is shown that it is sufficient to know the operational characteristics in the idle (kh.kh.) and short circuiting (KZ) modes alone in order to determine the operational characteristics of a conduction channel in the optimal mode, that is, in a mode of most complete energy conversion. The mode with which the required speed of movement is supported with minimal expenditures of energy is called the optimal mode of operation of a conduction cylinder. It is established that the characteristics of the corresponding optimal movement are expressed through the characteristics of the so called basis movements, whose number is one less than the number of electrodes.
Optimizing Long-Term Capital Planning for Special Operations Forces
2015-06-01
TERM CAPITAL PLANNING FOR SPECIAL OPERATIONS FORCES by Gretchen M. Radke June 2015 Thesis Advisor: Emily Craparo Co-Advisor: Jonathan Alt...REPORT TYPE AND DATES COVERED Master’s Thesis 4. TITLE AND SUBTITLE OPTIMIZING LONG-TERM CAPITAL PLANNING FOR SPECIAL OPERATIONS FORCES 5...words) The United States Special Operations Command (USSOCOM) J8 directorate is responsible for planning long-range capital expenditure for Special
Institute of Scientific and Technical Information of China (English)
周平; 向波; 柴天佑
2012-01-01
Advanced feedback control for optimal operation of mineral grinding process is usually based on the model predictive control (MPC) dynamic optimization. Since the MPC does not handle disturbances directly by controller design, it cannot achieve satisfactory effects in controlling complex grinding processes in the presence of strong disturbances and large uncertainties. In this paper, an improved disturbance observer (DOB) based MPC advanced feedback control is proposed to control the multivariable grinding operation. The improved DOB is based on the optimal achievable H 2 performance and can deal with disturbance observation for the nonminimum-phase delay systems. In this DOB-MPC advanced feedback control, the higher-level optimizer computes the optimal operation points by maximize the profit function and passes them to the MPC level. The MPC acts as a presetting controller and is employed to generate proper pre-setpoint for the lower-level basic feedback control system. The DOB acts as a compensator and improves the operation performance by dynamically compensating the setpoints for the basic control system according to the observed various disturbances and plant uncertainties. Several simulations are performed to demonstrate the proposed control method for grinding process operation.
Operation optimization of distributed generation using artificial intelligent techniques
Directory of Open Access Journals (Sweden)
Mahmoud H. Elkazaz
2016-06-01
Full Text Available Future smart grids will require an observable, controllable and flexible network architecture for reliable and efficient energy delivery. The use of artificial intelligence and advanced communication technologies is essential in building a fully automated system. This paper introduces a new technique for online optimal operation of distributed generation (DG resources, i.e. a hybrid fuel cell (FC and photovoltaic (PV system for residential applications. The proposed technique aims to minimize the total daily operating cost of a group of residential homes by managing the operation of embedded DG units remotely from a control centre. The target is formed as an objective function that is solved using genetic algorithm (GA optimization technique. The optimal settings of the DG units obtained from the optimization process are sent to each DG unit through a fully automated system. The results show that the proposed technique succeeded in defining the optimal operating points of the DGs that affect directly the total operating cost of the entire system.
Directory of Open Access Journals (Sweden)
Borja Amor-Tapia
2014-06-01
Full Text Available In this paper we examine how the relative position of a firm’s Return on Equity (ROE in industries affects the predictability of the next-year ROE levels, and the ROE changes from year to year. Using Nissim and Penman breakdown into operating and financing drivers, the significant role of the industry factor is established, although changes in signs suggest subtle non-linear relations in the drivers. Our study avoids problems originating from negative signs by analyzing sorts and by making new regressions with disaggregated second-order drivers by signs. This way, our results provide evidence of some different patterns in the influence of the first-level drivers of ROE (the operating factor and the financing factor, and the second-level drivers (profit margin, asset turnover, leverage and return spread on future profitability, depending on the industry spread. The results on the role of contextual factors to improve the estimation of future profitability remain consistent for small and large firms, although adding some nuances En este trabajo examinamos si la posición relativa del ROE de la empresa en el sector afecta a la estimación del nivel de ROE en el a˜no posterior, y a la estimación de su variación. Empleando el desglose operativo-financiero de Nissim y Penman, encontramos que el factor sectorial es significativo, aunque las variaciones de los signos sugieren la presencia de relaciones no lineales. Nuestro trabajo evita los problemas generados por los signos negativos en los ratios al emplear cuantiles y realizar regresiones independientes para los diferentes signos que toman las variables. De esta forma, los resultados muestran diferentes patrones en el impacto de los inductores del ROE de primer nivel (los factores operativo y financiero y de segundo nivel (margen de resultados, rotaciones de los activos, endeudamiento y diferencial de rentabilidad sobre la rentabilidad futura, dependiendo del diferencial de rentabilidad con
Optimal operation of Petlyuk distillation: Steady-state behavior
Directory of Open Access Journals (Sweden)
Ivar J. Halvorsen
2001-07-01
Full Text Available The "Petlyuk" or "dividing-wall" or "fully thermally coupled" distillation column is an interesting alternative to the conventional cascaded binary columns for separation of multi-component mixtures. However, the industrial use has been limited, and difficulties in operation have been reported as one reason. With three product compositions controlled, the system has two degrees of freedom left for on-line optimization. We show that the steady-state optimal solution surface is quite narrow, and depends strongly on disturbances and design parameters. Thus it seems difficult to achieve the potential energy savings compared to conventional approaches without a good control strategy. We discuss candidate variables which may be used as feedback variables in order to keep the column operation close to optimal in a "self-optimizing" control scheme.
Optimization of Operations Resources via Discrete Event Simulation Modeling
Joshi, B.; Morris, D.; White, N.; Unal, R.
1996-01-01
The resource levels required for operation and support of reusable launch vehicles are typically defined through discrete event simulation modeling. Minimizing these resources constitutes an optimization problem involving discrete variables and simulation. Conventional approaches to solve such optimization problems involving integer valued decision variables are the pattern search and statistical methods. However, in a simulation environment that is characterized by search spaces of unknown topology and stochastic measures, these optimization approaches often prove inadequate. In this paper, we have explored the applicability of genetic algorithms to the simulation domain. Genetic algorithms provide a robust search strategy that does not require continuity and differentiability of the problem domain. The genetic algorithm successfully minimized the operation and support activities for a space vehicle, through a discrete event simulation model. The practical issues associated with simulation optimization, such as stochastic variables and constraints, were also taken into consideration.
Operational optimization in the downstream; Otimizacao operacional no downstream
Energy Technology Data Exchange (ETDEWEB)
Silberman, Luis; Cunha, Filipe Silveira Ramos da [Petroleo Ipiranga, Porto Alegre, RS (Brazil)
2004-07-01
On the present competitive down stream's market, there is a great necessity of optimization aiming to guarantee the best price and quality of our clients. Our goal is to attend these expectations while we guarantee an efficient operation. The greatest question is how far we are from the ideal model. This way, a lot of projects have been executed during the last years aiming the operational optimization of all our activities. We divide the projects in 4 areas: Logistic (new modals distribution), Transport (transport optimization - quality and more deliveries with less trucks), Client Support (Internet Ipiranga and Support Center), Distribution Terminals Productivity (automation and environment). This work intend to present our ideal, perfect and complete Downstream Operation model. We will talk about how close we are of this ideal model and we will present the projects that we had already developed and implanted on the automation of the terminals and the logistics area. (author)
Optimizing Biorefinery Design and Operations via Linear Programming Models
Energy Technology Data Exchange (ETDEWEB)
Talmadge, Michael; Batan, Liaw; Lamers, Patrick; Hartley, Damon; Biddy, Mary; Tao, Ling; Tan, Eric
2017-03-28
The ability to assess and optimize economics of biomass resource utilization for the production of fuels, chemicals and power is essential for the ultimate success of a bioenergy industry. The team of authors, consisting of members from the National Renewable Energy Laboratory (NREL) and the Idaho National Laboratory (INL), has developed simple biorefinery linear programming (LP) models to enable the optimization of theoretical or existing biorefineries. The goal of this analysis is to demonstrate how such models can benefit the developing biorefining industry. It focuses on a theoretical multi-pathway, thermochemical biorefinery configuration and demonstrates how the biorefinery can use LP models for operations planning and optimization in comparable ways to the petroleum refining industry. Using LP modeling tools developed under U.S. Department of Energy's Bioenergy Technologies Office (DOE-BETO) funded efforts, the authors investigate optimization challenges for the theoretical biorefineries such as (1) optimal feedstock slate based on available biomass and prices, (2) breakeven price analysis for available feedstocks, (3) impact analysis for changes in feedstock costs and product prices, (4) optimal biorefinery operations during unit shutdowns / turnarounds, and (5) incentives for increased processing capacity. These biorefinery examples are comparable to crude oil purchasing and operational optimization studies that petroleum refiners perform routinely using LPs and other optimization models. It is important to note that the analyses presented in this article are strictly theoretical and they are not based on current energy market prices. The pricing structure assigned for this demonstrative analysis is consistent with $4 per gallon gasoline, which clearly assumes an economic environment that would favor the construction and operation of biorefineries. The analysis approach and examples provide valuable insights into the usefulness of analysis tools for
Optimal operation of Petlyuk distillation: Steady-state behavior
Ivar J. Halvorsen; Sigurd Skogestad
2001-01-01
The "Petlyuk" or "dividing-wall" or "fully thermally coupled" distillation column is an interesting alternative to the conventional cascaded binary columns for separation of multi-component mixtures. However, the industrial use has been limited, and difficulties in operation have been reported as one reason. With three product compositions controlled, the system has two degrees of freedom left for on-line optimization. We show that the steady-state optimal solution surface is quite narrow, an...
Optimization of operational planning for wind/hydro hybrid water supply systems
Energy Technology Data Exchange (ETDEWEB)
Vieira, Filipe; Ramos, Helena M. [Department of Civil Engineering, Instituto Superior Tecnico, Av. Rovisco Pais 1, 1049-001 Lisboa (Portugal)
2009-03-15
Water supply systems (WSS) frequently present high-energy consumption values, which correspond to the major expenses of these systems. Energy costs are a function of its real consumption and of the variability of the daily energy tariff. This paper presents a model of optimization for the energy efficiency in a water supply system. The system is equipped with a pump station and presents excess of available energy in the gravity branch. First, a water turbine is introduced in the system in order to use this excess of hydraulic available energy. Then, an optimization method to define the pump operation planning along the 24 h of simulation, as well as the analysis of the economic benefits resulting from the profit of wind energy to supply the water pumping, while satisfying the system constraints and population demands, is implemented, in order to minimize the global operational costs. The model, developed in MATLAB, uses linear programming and provides the planning strategy to take in each time step, which will influence the following hours. The simulation period considered is one day, sub-divided in hourly time steps. The rules obtained as output of the optimization procedures are subsequently introduced in a hydraulic simulator (e.g. EPANET), in order to verify the system behaviour along the simulation period. The results are compared with the normal operating mode (i.e. without optimization algorithm) and show that energy cost's savings are achieved dependently of the initial reservoir levels or volume. The insertion of the water turbine also generates significant economical benefits for the water supply system. (author)
Improved Large-Scale Process Cooling Operation through Energy Optimization
Directory of Open Access Journals (Sweden)
Kriti Kapoor
2013-11-01
Full Text Available This paper presents a study based on real plant data collected from chiller plants at the University of Texas at Austin. It highlights the advantages of operating the cooling processes based on an optimal strategy. A multi-component model is developed for the entire cooling process network. The model is used to formulate and solve a multi-period optimal chiller loading problem, posed as a mixed-integer nonlinear programming (MINLP problem. The results showed that an average energy savings of 8.57% could be achieved using optimal chiller loading as compared to the historical energy consumption data from the plant. The scope of the optimization problem was expanded by including a chilled water thermal storage in the cooling system. The effect of optimal thermal energy storage operation on the net electric power consumption by the cooling system was studied. The results include a hypothetical scenario where the campus purchases electricity at wholesale market prices and an optimal hour-by-hour operating strategy is computed to use the thermal energy storage tank.
Operations planning for agricultural harvesters using ant colony optimization
Directory of Open Access Journals (Sweden)
A. Bakhtiari
2013-07-01
Full Text Available An approach based on ant colony optimization for the generation for optimal field coverage plans for the harvesting operations using the optimal track sequence principle B-patterns was presented. The case where the harvester unloads to a stationary facility located out of the field area, or in the field boundary, was examined. In this operation type there are capacity constraints to the load that a primary unit, or a harvester in this specific case, can carry and consequently, it is not able to complete the task of harvesting a field area and therefore it has to leave the field area, to unload, and return to continue the task one or more times. Results from comparing the optimal plans with conventional plans generated by operators show reductions in the in-field nonworking distance in the range of 19.3-42.1% while the savings in the total non-working distance were in the range of 18-43.8%. These savings provide a high potential for the implementation of the ant colony optimization approach for the case of harvesting operations that are not supported by transport carts for the out-of-the-field removal of the crops, a practice case that is normally followed in developing countries, due to lack of resources.
Energy-optimal programming and scheduling of the manufacturing operations
Badea, N.; Frumuşanu, G.; Epureanu, A.
2016-08-01
The shop floor energy system covers the energy consumed for both the air conditioning and manufacturing processes. At the same time, most of energy consumed in manufacturing processes is converted in heat released in the shop floor interior and has a significant influence on the microclimate. Both these components of the energy consumption have a time variation that can be realistic assessed. Moreover, the consumed energy decisively determines the environmental sustainability of the manufacturing operation, while the expenditure for running the shop floor energy system is a significant component of the manufacturing operations cost. Finally yet importantly, the energy consumption can be fundamentally influenced by properly programming and scheduling of the manufacturing operations. In this paper, we present a method for modeling and energy-optimal programming & scheduling the manufacturing operations. In this purpose, we have firstly identified two optimization targets, namely the environmental sustainability and the economic efficiency. Then, we have defined three optimization criteria, which can assess the degree of achieving these targets. Finally, we have modeled the relationship between the optimization criteria and the parameters of programming and scheduling. In this way, it has been revealed that by adjusting these parameters one can significantly improve the sustainability and efficiency of manufacturing operations. A numerical simulation has proved the feasibility and the efficiency of the proposed method.
Optimal Operation of Data Centers in Future Smart Grid
Ghamkhari, Seyed Mahdi
The emergence of cloud computing has established a growing trend towards building massive, energy-hungry, and geographically distributed data centers. Due to their enormous energy consumption, data centers are expected to have major impact on the electric grid by significantly increasing the load at locations where they are built. However, data centers also provide opportunities to help the grid with respect to robustness and load balancing. For instance, as data centers are major and yet flexible electric loads, they can be proper candidates to offer ancillary services, such as voluntary load reduction, to the smart grid. Also, data centers may better stabilize the price of energy in the electricity markets, and at the same time reduce their electricity cost by exploiting the diversity in the price of electricity in the day-ahead and real-time electricity markets. In this thesis, such potentials are investigated within an analytical profit maximization framework by developing new mathematical models based on queuing theory. The proposed models capture the trade-off between quality-of-service and power consumption in data centers. They are not only accurate, but also they posses convexity characteristics that facilitate joint optimization of data centers' service rates, demand levels and demand bids to different electricity markets. The analysis is further expanded to also develop a unified comprehensive energy portfolio optimization for data centers in the future smart grid. Specifically, it is shown how utilizing one energy option may affect selecting other energy options that are available to a data center. For example, we will show that the use of on-site storage and the deployment of geographical workload distribution can particularly help data centers in utilizing high-risk energy options such as renewable generation. The analytical approach in this thesis takes into account service-level-agreements, risk management constraints, and also the statistical
The effect of pre-operative optimization on post-operative outcome in Crohn's disease resections
DEFF Research Database (Denmark)
El-Hussuna, Alaa; Iesalnieks, Igors; Horesh, Nir
2017-01-01
on the post-operative outcome in CD. METHOD: This is a multicentre retrospective cohort study. The primary outcome was 30-day post-operative complications. Secondary outcomes were intra-abdominal septic complications, surgical site infection (SSI), re-operation, length of post-operative stay in a hospital......BACKGROUND: The timing of surgical intervention in Crohn's disease (CD) may depend on pre-operative optimization (PO) which includes different interventions to decrease the risk for unfavourable post-operative outcome. The objective of this study was to investigate the effect of multi-model PO...
Analysis of Optimal Operation of an Energy Integrated Distillation Plant
DEFF Research Database (Denmark)
Li, Hong Wen; Hansen, C.A.; Gani, Rafiqul
2003-01-01
distillation plant is investigated more closely with the purpose of elucidating essential decisions behind planning experiments, which are suitable for identifying models and constraints. The basis for analysis of optimal operation is the type of operation upon which an application focuses. In this paper...... and their influence upon the further decisions behind the experimental design. An energy-integrated distillation column, which may exhibit fold bifurcations, is used as a relevant example process....
Operational characteristics optimization of human-computer system
Zulquernain Mallick; Irfan Anjum Badruddin magami; Khaleed Hussain Tandur
2010-01-01
Computer operational parameters are having vital influence on the operators efficiency from readability viewpoint. Four parameters namely font, text/background color, viewing angle and viewing distance are analyzed. The text reading task, in the form of English text, was presented on the computer screen to the participating subjects and their performance, measured in terms of number of words read per minute (NWRPM), was recorded. For the purpose of optimization, the Taguchi method is u...
Optimal Operation of Energy Storage in Power Transmission and Distribution
2015-01-01
In this thesis, we investigate optimal operation of energy storage units in power transmission and distribution grids. At transmission level, we investigate the problem where an investor-owned independently-operated energy storage system seeks to offer energy and ancillary services in the day-ahead and real-time markets. We specifically consider the case where a significant portion of the power generated in the grid is from renewable energy resources and there exists significant uncertainty i...
Synthesis, design and operation optimization of a marine energy system
Energy Technology Data Exchange (ETDEWEB)
Dimopoulos, George G.; Kougioufas, Aristotelis V.; Frangopoulos, Christos A. [National Technical University of Athens, School of Naval Architecture and Marine Engineering, Heroon Polytechniou 9, 157 73 Zografou (Greece)
2008-02-15
Recent developments in the global fuel markets imposed the need of increased fuel economy and cost effectiveness of sea-going vessels. Optimization of the ship's total energy system, as a whole, is now a demand of the marine industry sector in order to address the significant increase of installation and operational costs. This study is focused on the synthesis, design and operation optimization of a marine energy system. A realistic example of a cruise liner energy system has been selected. Basic technology options have been identified and a generic energy system model has been constructed. Various configuration options, types of technologies and existence of components have been incorporated in the generic system. In addition, time varying operational requirements for this cruise liner ship have been considered, resulting in a time dependent operation optimization problem. The complete optimization problem has been solved using a novel algorithm, inspired by evolutionary and social behavior metaphors. A parametric analysis with respect to the fuel price demonstrated changes in the optimum synthesis of the system. (author)
Positive-operator-valued measure optimization of classical correlations
Hamieh, S; Kobes, R; Zaraket, H
2004-01-01
We study the problem of optimization over positive-operator-valued measures to extract classical correlation in a bipartite quantum system. The proposed method is applied to binary states only. Moreover, to illustrate this method, an explicit example is studied in detail.
Simulation and OR (operations research) in combination for practical optimization
N. van Dijk; E. van der Sluis; R. Haijema; A. Al-Ibrahim; J. van der Wal
2005-01-01
Should we pool capacities or not? This is a question that one can regularly be confronted with in operations and service management. It is a question that necessarily requires a combination of queueing (as OR discipline) and simulation (as evaluative tool) and further steps for optimization. It will
Design procedure for optimizing CMOS low noise operational amplifiers
Institute of Scientific and Technical Information of China (English)
Li Zhiyuan; Ye Yizheng; Ma Jianguo
2009-01-01
This paper presents and experimentally verifies an optimized design procedure for a CMOS low noise operational amplifier.The design procedure focuses on the noise performance,which is the key requirement for low noise operational amplifiers.Based on the noise level and other specifications such as bandwidth,signal swing,slew rate,and power consumption,the device sizes and the biasing conditions are derived.In order to verify the proposed design procedure,a three-stage operational amplifier has been designed.The device parameters obtained from the proposed design procedure closely agree with the simulated results obtained by using HSPICE.
Near-Optimal Operation of Dual-Fuel Launch Vehicles
Ardema, M. D.; Chou, H. C.; Bowles, J. V.
1996-01-01
A near-optimal guidance law for the ascent trajectory from earth surface to earth orbit of a fully reusable single-stage-to-orbit pure rocket launch vehicle is derived. Of interest are both the optimal operation of the propulsion system and the optimal flight path. A methodology is developed to investigate the optimal throttle switching of dual-fuel engines. The method is based on selecting propulsion system modes and parameters that maximize a certain performance function. This function is derived from consideration of the energy-state model of the aircraft equations of motion. Because the density of liquid hydrogen is relatively low, the sensitivity of perturbations in volume need to be taken into consideration as well as weight sensitivity. The cost functional is a weighted sum of fuel mass and volume; the weighting factor is chosen to minimize vehicle empty weight for a given payload mass and volume in orbit.
Data reconciliation and optimal operation of a Catalytic naphtha reformer
Directory of Open Access Journals (Sweden)
Tore Lid
2008-10-01
Full Text Available The naphtha reforming process converts low-octane gasoline blending components to high-octane components for use in high-performance gasoline fuels. The reformer also has an important function as the producer of hydrogen to the refinery hydrotreaters. A process model based on a unit model structure, is used for estimation of the process condition using data reconciliation. Measurements are classified as redundant or non redundant and the model variables are classified as observable, barely observable or unobservable. The computed uncertainty of the measured and unmeasured variables shows that even if a variable is observable it may have a very large uncertainty and may thereby be practically unobservable. The process condition at 21 data points, sampled from two years of operation, was reconciled and used to optimize the process operation. There are large seasonal variations in the reformer product price and two operational cases are studied. In case 1, the product price is high and throughput is maximized with respect to process and product quality constraints. In case 2, the product price is low and the throughput is minimized with respect to a low constraint on the hydrogen production. Based on the characteristics of the optimal operation, a "self optimizing" control structure is suggested for each of the two operational cases.
Research on operation optimization of multi-product pipeline
Energy Technology Data Exchange (ETDEWEB)
Liang, Y.; Gong, J.; Kang, Z.; Yang, F. [Petroleum Univ., Beijing (China). College of Petroleum Engineering
2004-07-01
In order to operate complex, long-distance pipelines safely and efficiently while meeting energy demands, operators require offline optimization simulation software. This paper presented the newly developed STROBER software for simulating the operations of multi-product pipelines whose hydraulic characteristics vary continuously with batch movement in the pipeline. The software was based on a mathematical model that optimized the configuration of pumps in order to minimize the electricity costs associated with operating a multi-product pipeline. The energy conservation equation met the following restraining factors: the flow rate in an initial pumping station was as stable as possible for specific periods of time; the inlet and outlet pressures of the pumping stations and the pressures of some special points were within the preset limits; and, the off-take task was completed during a prescribed time. The optimization theory was solved using dynamic programming. The peak-to-valley ratio of electricity price was also taken into consideration in order to encourage pipeline companies to consume most electricity during off-peak periods of the electrical network. The STROBER software was successfully applied in the start-up and current operation of the LanZhou-ChengDu-ChongQing multi-product pipeline in China. This complex pipeline includes 13 off-take stations, 2 pressure-reducing stations and 4 pumping stations. The software provided off-take plans and information on pressure control. 8 refs., 2 tabs., 4 figs.
Annealing Ant Colony Optimization with Mutation Operator for Solving TSP
Directory of Open Access Journals (Sweden)
Abdulqader M. Mohsen
2016-01-01
Full Text Available Ant Colony Optimization (ACO has been successfully applied to solve a wide range of combinatorial optimization problems such as minimum spanning tree, traveling salesman problem, and quadratic assignment problem. Basic ACO has drawbacks of trapping into local minimum and low convergence rate. Simulated annealing (SA and mutation operator have the jumping ability and global convergence; and local search has the ability to speed up the convergence. Therefore, this paper proposed a hybrid ACO algorithm integrating the advantages of ACO, SA, mutation operator, and local search procedure to solve the traveling salesman problem. The core of algorithm is based on the ACO. SA and mutation operator were used to increase the ants population diversity from time to time and the local search was used to exploit the current search area efficiently. The comparative experiments, using 24 TSP instances from TSPLIB, show that the proposed algorithm outperformed some well-known algorithms in the literature in terms of solution quality.
Annealing Ant Colony Optimization with Mutation Operator for Solving TSP.
Mohsen, Abdulqader M
2016-01-01
Ant Colony Optimization (ACO) has been successfully applied to solve a wide range of combinatorial optimization problems such as minimum spanning tree, traveling salesman problem, and quadratic assignment problem. Basic ACO has drawbacks of trapping into local minimum and low convergence rate. Simulated annealing (SA) and mutation operator have the jumping ability and global convergence; and local search has the ability to speed up the convergence. Therefore, this paper proposed a hybrid ACO algorithm integrating the advantages of ACO, SA, mutation operator, and local search procedure to solve the traveling salesman problem. The core of algorithm is based on the ACO. SA and mutation operator were used to increase the ants population diversity from time to time and the local search was used to exploit the current search area efficiently. The comparative experiments, using 24 TSP instances from TSPLIB, show that the proposed algorithm outperformed some well-known algorithms in the literature in terms of solution quality.
EP BASED PSO METHOD FOR SOLVING PROFIT BASED MULTI AREA UNIT COMMITMENT PROBLEM
Directory of Open Access Journals (Sweden)
K. VENKATESAN
2015-04-01
Full Text Available This paper presents a new approach to solve the profit based multi area unit commitment problem (PBMAUCP using an evolutionary programming based particle swarm optimization (EPPSO method. The objective of this paper is to maximize the profit of generation companies (GENCOs with considering system social benefit. The proposed method helps GENCOs to make a decision, how much power and reserve should be sold in markets, and how to schedule generators in order to receive the maximum profit. Joint operation of generation resources can result in significant operational cost savings. Power transfer between the areas through the tie lines depends upon the operating cost of generation at each hour and tie line transfer limits. The tie line transfer limits were considered as a set of constraints during optimization process to ensure the system security and reliability. The overall algorithm can be implemented on an IBM PC, which can process a fairly large system in a reasonable period of time. Case study of four areas with different load pattern each containing 7 units (NTPS and 26 units connected via tie lines have been taken for analysis. Numerical results showed comparing the profit of evolutionary programming-based particle swarm optimization method (EPPSO with conventional dynamic programming (DP, evolutionary programming (EP, and particle swarm optimization (PSO method. Experimental results shows that the application of this evolutionary programming based particle swarm optimization method have the potential to solve profit based multi area unit commitment problem with lesser computation time.
Future Horizons For Optimal Operation of Mosul Dam Reservoir
Directory of Open Access Journals (Sweden)
Abdulwahab Gazal
2013-05-01
Full Text Available In this study, The Discrete Differential Dynamic Programming (DDDP has been applied to the operation of Mosul dam reservoir on Tigris river, North of Iraq. The simulation technique (SM has been used to evaluate the results obtained from the (DDDP model. The aim of this study is to obtain the present and future optimal monthly reservoir operation policies for the years (2007, 2017, and 2027 through fulfilling the irrigation requirements of Jazira Irrigation Project and water supply requirements according to different operation states. The states included the operation of Northern only, Northern and Eastern; and the Northern, Eastern and Southern Jazira Irrigation Projects for minimum annual inflow in all states. The results indicated water deficit occurrence with the second and third states. For optimization model, the water deficits were distributed over long periods which helped to minimize the penalty, and the reservoir storages were within the upper and lower operating storage limits. Whereas for simulation model the water deficits were concentrated within short periods and the reservoir storages declined below the lower operating storage limit.
Optimal operation of hybrid-SITs under a SBO accident
Energy Technology Data Exchange (ETDEWEB)
Jeon, In Seop, E-mail: inseopjeon@kaist.ac.kr [Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 305-701 (Korea, Republic of); Heo, Sun, E-mail: sunnysunny@khnp.co.kr [Central Research Institute, Korea Hydro & Nuclear Power Co., 70 Yuseong-daero 1312 beon-gil, Yuseong-gu, Daejeon 305-343 (Korea, Republic of); Kang, Hyun Gook, E-mail: hyungook@kaist.ac.kr [Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 305-701 (Korea, Republic of)
2016-02-15
Highlights: • Operation strategy of hybrid-SIT (H-SIT) in station blackout (SBO) is developed. • There are five main factors which have to be carefully treated in the development of the operation strategy. • Optimal value of each main factor is investigated analytically and then through thermal-hydraulic analysis using computer code. • The optimum operation strategy is suggested based on the optimal value of the main factors. - Abstract: A hybrid safety injection tank (H-SIT) is designed to enhance the capability of pressurized water reactors against high-pressure accidents which might be caused by the combined accidents accompanied by station blackout (SBO), and is suggested as a useful alternative to electricity-driven motor injection pumps. The main purpose of the H-SIT is to provide coolant to the core so that core safety can be maintained for a longer period. As H-SITs have a limited inventory, their efficient use in cooling down the core is paramount to maximize the available time for long-term cooling component restoration. Therefore, an optimum operation strategy must be developed to support the operators for the most efficient H-SIT use. In this study, the main factors which have to be carefully treated in the development of an operation strategy are first identified. Then the optimal value of each main factor is investigated analytically, a process useful to get the basis of the global optimum points. Based on these analytical optimum points, a thermal-hydraulic analysis using MARS code is performed to get more accurate values and to verify the results of the analytical study. The available time for long-term cooling component restoration is also estimated. Finally, an integrated optimum operation strategy for H-SITs in SBO is suggested.
OPF-Based Optimal Location of Two Systems Two Terminal HVDC to Power System Optimal Operation
Directory of Open Access Journals (Sweden)
Mehdi Abolfazli
2013-04-01
Full Text Available In this paper a suitable mathematical model of the two terminal HVDC system is provided for optimal power flow (OPF and optimal location based on OPF such power injection model. The ability of voltage source converter (VSC-based HVDC to independently control active and reactive power is well represented by the model. The model is used to develop an OPF-based optimal location algorithm of two systems two terminal HVDC to minimize the total fuel cost and active power losses as objective function. The optimization framework is modeled as non-linear programming (NLP and solved by Matlab and GAMS softwares. The proposed algorithm is implemented on the IEEE 14- and 30-bus test systems. The simulation results show ability of two systems two terminal HVDC in improving the power system operation. Furthermore, two systems two terminal HVDC is compared by PST and OUPFC in the power system operation from economical and technical aspects.
Comparison of operation optimization methods in energy system modelling
DEFF Research Database (Denmark)
Ommen, Torben Schmidt; Markussen, Wiebke Brix; Elmegaard, Brian
2013-01-01
, possibilities for decoupling production constraints may be valuable. Introduction of heat pumps in the district heating network may pose this ability. In order to evaluate if the introduction of heat pumps is economically viable, we develop calculation methods for the operation patterns of each of the used...... energy technologies. In the paper, three frequently used operation optimization methods are examined with respect to their impact on operation management of the combined technologies. One of the investigated approaches utilises linear programming for optimisation, one uses linear programming with binary...... operation constraints, while the third approach uses nonlinear programming. In the present case the non-linearity occurs in the boiler efficiency of power plants and the cv-value of an extraction plant. The linear programming model is used as a benchmark, as this type is frequently used, and has the lowest...
The optimization of operating parameters on microalgae upscaling process planning.
Ma, Yu-An; Huang, Hsin-Fu; Yu, Chung-Chyi
2016-03-01
The upscaling process planning developed in this study primarily involved optimizing operating parameters, i.e., dilution ratios, during process designs. Minimal variable cost was used as an indicator for selecting the optimal combination of dilution ratios. The upper and lower mean confidence intervals obtained from the actual cultured cell density data were used as the final cell density stability indicator after the operating parameters or dilution ratios were selected. The process planning method and results were demonstrated through three case studies of batch culture simulation. They are (1) final objective cell densities were adjusted, (2) high and low light intensities were used for intermediate-scale cultures, and (3) the number of culture days was expressed as integers for the intermediate-scale culture.
Wind farm operation planning using optimal pitch angle pattern (OPAP)
Energy Technology Data Exchange (ETDEWEB)
Moskalenko, Natalia S.; Rudion, K. [Magdeburg Univ. (Germany). Chair for Electric Power Networks and Renewable Energy Sources
2011-07-01
This paper presents the possibilities of optimal operation planning to maximize the energy production from a wind farm based on optimal pitch angle pattern (OPAP). The current status of this work is to investigate the influence of the pitch angle adaptation of single wind turbines (WTs) on the overall energy yield of the farm. The approach proposed in this paper assumes a selective change of the pitch angle of the chosen WTs from the optimal value, which corresponds to the maximal utilization of kinetic energy from the wind flow, in order to minimize wake effect influence on the overall energy yield of the farm. In this paper the fundamental assumptions of the proposed approach will be specified and the calculation algorithm will be presented. Furthermore, an exemplary test system will be defined and chosen scenarios will be calculated in order to show the potentials of the OPAP method. (orig.)
Optimal line drop compensation parameters under multi-operating conditions
Wan, Yuan; Li, Hang; Wang, Kai; He, Zhe
2017-01-01
Line Drop Compensation (LDC) is a main function of Reactive Current Compensation (RCC) which is developed to improve voltage stability. While LDC has benefit to voltage, it may deteriorate the small-disturbance rotor angle stability of power system. In present paper, an intelligent algorithm which is combined by Genetic Algorithm (GA) and Backpropagation Neural Network (BPNN) is proposed to optimize parameters of LDC. The objective function proposed in present paper takes consideration of voltage deviation and power system oscillation minimal damping ratio under multi-operating conditions. A simulation based on middle area of Jiangxi province power system is used to demonstrate the intelligent algorithm. The optimization result shows that coordinate optimized parameters can meet the multioperating conditions requirement and improve voltage stability as much as possible while guaranteeing enough damping ratio.
Directory of Open Access Journals (Sweden)
Fei Wang
2017-07-01
Full Text Available The optimized dispatch of different distributed generations (DGs in stand-alone microgrid (MG is of great significance to the operation’s reliability and economy, especially for energy crisis and environmental pollution. Based on controllable load (CL and combined cooling-heating-power (CCHP model of micro-gas turbine (MT, a multi-objective optimization model with relevant constraints to optimize the generation cost, load cut compensation and environmental benefit is proposed in this paper. The MG studied in this paper consists of photovoltaic (PV, wind turbine (WT, fuel cell (FC, diesel engine (DE, MT and energy storage (ES. Four typical scenarios were designed according to different day types (work day or weekend and weather conditions (sunny or rainy in view of the uncertainty of renewable energy in variable situations and load fluctuation. A modified dispatch strategy for CCHP is presented to further improve the operation economy without reducing the consumers’ comfort feeling. Chaotic optimization and elite retention strategy are introduced into basic particle swarm optimization (PSO to propose modified chaos particle swarm optimization (MCPSO whose search capability and convergence speed are improved greatly. Simulation results validate the correctness of the proposed model and the effectiveness of MCPSO algorithm in the optimized operation application of stand-alone MG.
POSSIBILITIES FOR OPTIMIZATION OF CIRCUIT ACCELERATING OPERATION OF ELECTROMAGNETS
Directory of Open Access Journals (Sweden)
S. S. Stoyanova
2005-01-01
Full Text Available The paper reveals an accelerating circuit for electromagnet operation with the help of an additional resistor R that is shunted with a capacitor C. Resistor R is connected in series with the electromagnet winding. The possibility of the circuit optimization has been substantiated with the purpose to limit the final speed with which a movable part of the electromagnet reaches a limiter. Such circuit may find its application in relay protection.
Optimizing integrated airport surface and terminal airspace operations under uncertainty
Bosson, Christabelle S.
In airports and surrounding terminal airspaces, the integration of surface, arrival and departure scheduling and routing have the potential to improve the operations efficiency. Moreover, because both the airport surface and the terminal airspace are often altered by random perturbations, the consideration of uncertainty in flight schedules is crucial to improve the design of robust flight schedules. Previous research mainly focused on independently solving arrival scheduling problems, departure scheduling problems and surface management scheduling problems and most of the developed models are deterministic. This dissertation presents an alternate method to model the integrated operations by using a machine job-shop scheduling formulation. A multistage stochastic programming approach is chosen to formulate the problem in the presence of uncertainty and candidate solutions are obtained by solving sample average approximation problems with finite sample size. The developed mixed-integer-linear-programming algorithm-based scheduler is capable of computing optimal aircraft schedules and routings that reflect the integration of air and ground operations. The assembled methodology is applied to a Los Angeles case study. To show the benefits of integrated operations over First-Come-First-Served, a preliminary proof-of-concept is conducted for a set of fourteen aircraft evolving under deterministic conditions in a model of the Los Angeles International Airport surface and surrounding terminal areas. Using historical data, a representative 30-minute traffic schedule and aircraft mix scenario is constructed. The results of the Los Angeles application show that the integration of air and ground operations and the use of a time-based separation strategy enable both significant surface and air time savings. The solution computed by the optimization provides a more efficient routing and scheduling than the First-Come-First-Served solution. Additionally, a data driven analysis is
Multi-objective nested algorithms for optimal reservoir operation
Delipetrev, Blagoj; Solomatine, Dimitri
2016-04-01
The optimal reservoir operation is in general a multi-objective problem, meaning that multiple objectives are to be considered at the same time. For solving multi-objective optimization problems there exist a large number of optimization algorithms - which result in a generation of a Pareto set of optimal solutions (typically containing a large number of them), or more precisely, its approximation. At the same time, due to the complexity and computational costs of solving full-fledge multi-objective optimization problems some authors use a simplified approach which is generically called "scalarization". Scalarization transforms the multi-objective optimization problem to a single-objective optimization problem (or several of them), for example by (a) single objective aggregated weighted functions, or (b) formulating some objectives as constraints. We are using the approach (a). A user can decide how many multi-objective single search solutions will generate, depending on the practical problem at hand and by choosing a particular number of the weight vectors that are used to weigh the objectives. It is not guaranteed that these solutions are Pareto optimal, but they can be treated as a reasonably good and practically useful approximation of a Pareto set, albeit small. It has to be mentioned that the weighted-sum approach has its known shortcomings because the linear scalar weights will fail to find Pareto-optimal policies that lie in the concave region of the Pareto front. In this context the considered approach is implemented as follows: there are m sets of weights {w1i, …wni} (i starts from 1 to m), and n objectives applied to single objective aggregated weighted sum functions of nested dynamic programming (nDP), nested stochastic dynamic programming (nSDP) and nested reinforcement learning (nRL). By employing the multi-objective optimization by a sequence of single-objective optimization searches approach, these algorithms acquire the multi-objective properties
Profit pools: a fresh look at strategy.
Gadiesh, O; Gilbert, J L
1998-01-01
In charting strategy, many managers focus on revenue growth, assuming that profits will follow. But that approach is dangerous: today's deep revenue pool may become tomorrow's dry hole. To create strategies that result in profitable growth, managers need to look beyond revenues to see the shape of their industry's profit pool. The authors define an industry's profit pool as the total profits earned at all points along the industry's value chain. Although the concept is simple, the structure of a profit pool is usually quite complex. The pool will be deeper in some segments of the value chain than in others, and depths will vary within an individual segment as well. Segment profitability may, for example, vary widely by customer group, product category, geographic market, and distribution channel. Moreover, the pattern of profit concentration in an industry will often be very different from the pattern of revenue concentration. The authors describe how successful companies have gained competitive advantage by developing sophisticated profit-pool strategies. They explain how U-Haul identified new sources of profit in the consumer-truck-rental industry; how Merck reached beyond its traditional value-chain role to protect its profits in the pharmaceuticals industry; how Dell rebounded from a misguided channel decision by refocusing on its traditional source of profit; and how Anheuser-Busch made a series of astute product, pricing, and operating decisions to dominate the beer industry's profit pool. The companies with the best understanding of their industry's profit pool, the authors argue, will be in the best position to thrive over the long term.
Sobh, Tarek M.; Tibrewal, Abhilasha
2006-01-01
Operating systems theory primarily concentrates on the optimal use of computing resources. This paper presents an alternative approach to teaching and studying operating systems design and concepts by way of parametrically optimizing critical operating system functions. Detailed examples of two critical operating systems functions using the…
Optimal reservoir operation policies using novel nested algorithms
Delipetrev, Blagoj; Jonoski, Andreja; Solomatine, Dimitri
2015-04-01
Historically, the two most widely practiced methods for optimal reservoir operation have been dynamic programming (DP) and stochastic dynamic programming (SDP). These two methods suffer from the so called "dual curse" which prevents them to be used in reasonably complex water systems. The first one is the "curse of dimensionality" that denotes an exponential growth of the computational complexity with the state - decision space dimension. The second one is the "curse of modelling" that requires an explicit model of each component of the water system to anticipate the effect of each system's transition. We address the problem of optimal reservoir operation concerning multiple objectives that are related to 1) reservoir releases to satisfy several downstream users competing for water with dynamically varying demands, 2) deviations from the target minimum and maximum reservoir water levels and 3) hydropower production that is a combination of the reservoir water level and the reservoir releases. Addressing such a problem with classical methods (DP and SDP) requires a reasonably high level of discretization of the reservoir storage volume, which in combination with the required releases discretization for meeting the demands of downstream users leads to computationally expensive formulations and causes the curse of dimensionality. We present a novel approach, named "nested" that is implemented in DP, SDP and reinforcement learning (RL) and correspondingly three new algorithms are developed named nested DP (nDP), nested SDP (nSDP) and nested RL (nRL). The nested algorithms are composed from two algorithms: 1) DP, SDP or RL and 2) nested optimization algorithm. Depending on the way we formulate the objective function related to deficits in the allocation problem in the nested optimization, two methods are implemented: 1) Simplex for linear allocation problems, and 2) quadratic Knapsack method in the case of nonlinear problems. The novel idea is to include the nested
Harmonic component detection: Optimized Spectral Kurtosis for operational modal analysis
Dion, J.-L.; Tawfiq, I.; Chevallier, G.
2012-01-01
This work is a contribution in the field of Operational Modal Analysis to identify the modal parameters of mechanical structures using only measured responses. The study deals with structural responses coupled with harmonic components amplitude and frequency modulated in a short range, a common combination for mechanical systems with engines and other rotating machines in operation. These harmonic components generate misleading data interpreted erroneously by the classical methods used in OMA. The present work attempts to differentiate maxima in spectra stemming from harmonic components and structural modes. The detection method proposed is based on the so-called Optimized Spectral Kurtosis and compared with others definitions of Spectral Kurtosis described in the literature. After a parametric study of the method, a critical study is performed on numerical simulations and then on an experimental structure in operation in order to assess the method's performance.
Directory of Open Access Journals (Sweden)
A. M. Dalavi
2015-09-01
Full Text Available Optimization of hole-making operations plays a crucial role in which tool travel and tool switch scheduling are the two major issues. Industrial applications such as moulds, dies, engine block etc. consist of large number of holes having different diameters, depths and surface finish. This results into to a large number of machining operations like drilling, reaming or tapping to achieve the final size of individual hole. Optimal sequence of operations and associated cutting speeds, which reduce the overall processing cost of these hole-making operations are essential to reach desirable products. In order to achieve this, an attempt is made by developing an effective methodology. An example of the injection mould is considered to demonstrate the proposed approach. The optimization of this example is carried out using recently developed particle swarm optimization (PSO algorithm. The results obtained using PSO are compared with those obtained using tabu search method. It is observed that results obtained using PSO are slightly better than those obtained using tabu search method.
Cost related sensitivity analysis for optimal operation of a grid-parallel PEM fuel cell power plant
El-Sharkh, M. Y.; Tanrioven, M.; Rahman, A.; Alam, M. S.
Fuel cell power plants (FCPP) as a combined source of heat, power and hydrogen (CHP&H) can be considered as a potential option to supply both thermal and electrical loads. Hydrogen produced from the FCPP can be stored for future use of the FCPP or can be sold for profit. In such a system, tariff rates for purchasing or selling electricity, the fuel cost for the FCPP/thermal load, and hydrogen selling price are the main factors that affect the operational strategy. This paper presents a hybrid evolutionary programming and Hill-Climbing based approach to evaluate the impact of change of the above mentioned cost parameters on the optimal operational strategy of the FCPP. The optimal operational strategy of the FCPP for different tariffs is achieved through the estimation of the following: hourly generated power, the amount of thermal power recovered, power trade with the local grid, and the quantity of hydrogen that can be produced. Results show the importance of optimizing system cost parameters in order to minimize overall operating cost.
Profit margins in Japanese retailing
J.C.A. Potjes; A.R. Thurik (Roy)
1993-01-01
textabstractUsing a rich data source, we explain differences and developments in profit margins of medium-sized stores in Japan. We conclude that the protected environment enables the retailer to pass on all operating costs to the customers and to obtain a relatively high basic income. High service
Profit margins in Japanese retailing
J.C.A. Potjes; A.R. Thurik (Roy)
1993-01-01
textabstractUsing a rich data source, we explain differences and developments in profit margins of medium-sized stores in Japan. We conclude that the protected environment enables the retailer to pass on all operating costs to the customers and to obtain a relatively high basic income. High service
Nonlinear Burn Control and Operating Point Optimization in ITER
Boyer, Mark; Schuster, Eugenio
2013-10-01
Control of the fusion power through regulation of the plasma density and temperature will be essential for achieving and maintaining desired operating points in fusion reactors and burning plasma experiments like ITER. In this work, a volume averaged model for the evolution of the density of energy, deuterium and tritium fuel ions, alpha-particles, and impurity ions is used to synthesize a multi-input multi-output nonlinear feedback controller for stabilizing and modulating the burn condition. Adaptive control techniques are used to account for uncertainty in model parameters, including particle confinement times and recycling rates. The control approach makes use of the different possible methods for altering the fusion power, including adjusting the temperature through auxiliary heating, modulating the density and isotopic mix through fueling, and altering the impurity density through impurity injection. Furthermore, a model-based optimization scheme is proposed to drive the system as close as possible to desired fusion power and temperature references. Constraints are considered in the optimization scheme to ensure that, for example, density and beta limits are avoided, and that optimal operation is achieved even when actuators reach saturation. Supported by the NSF CAREER award program (ECCS-0645086).
Profit maximization mitigates competition
DEFF Research Database (Denmark)
Dierker, Egbert; Grodal, Birgit
1996-01-01
We consider oligopolistic markets in which the notion of shareholders' utility is well-defined and compare the Bertrand-Nash equilibria in case of utility maximization with those under the usual profit maximization hypothesis. Our main result states that profit maximization leads to less price...... competition than utility maximization. Since profit maximization tends to raise prices, it may be regarded as beneficial for the owners as a whole. Moreover, if profit maximization is a good proxy for utility maximization, then there is no need for a general equilibrium analysis that takes the distribution...... of profits among consumers fully into account and partial equilibrium analysis suffices...
Design of an operational transconductance amplifier applying multiobjective optimization techniques
Directory of Open Access Journals (Sweden)
Roberto Pereira-Arroyo
2014-02-01
Full Text Available In this paper, the problem at hand consists in the sizing of an Operational Transconductance Amplifier (OTA. The Pareto front is introduced as a useful analysis concept in order to explore the design space of such analog circuit. A genetic algorithm (GA is employed to automatically detect this front in a process that efficiently finds optimal parameterizations and their corresponding values in an aggregate fitness space. Since the problem is treated as a multi-objective optimization task, different measures of the amplifier like the transconductance, the slew rate, the linear range and the input capacitance are used as fitness functions. Finally, simulation results are presented, using a standard 0,5μm CMOS technology.
Optimized Algorithms for Prediction within Robotic Tele-Operative Interfaces
Martin, Rodney A.; Wheeler, Kevin R.; SunSpiral, Vytas; Allan, Mark B.
2006-01-01
Robonaut, the humanoid robot developed at the Dexterous Robotics Laboratory at NASA Johnson Space Center serves as a testbed for human-robot collaboration research and development efforts. One of the primary efforts investigates how adjustable autonomy can provide for a safe and more effective completion of manipulation-based tasks. A predictive algorithm developed in previous work was deployed as part of a software interface that can be used for long-distance tele-operation. In this paper we provide the details of this algorithm, how to improve upon the methods via optimization, and also present viable alternatives to the original algorithmic approach. We show that all of the algorithms presented can be optimized to meet the specifications of the metrics shown as being useful for measuring the performance of the predictive methods. Judicious feature selection also plays a significant role in the conclusions drawn.
Optimal operation of integrated processes. Studies on heat recovery systems
Energy Technology Data Exchange (ETDEWEB)
Glemmestad, Bjoern
1997-12-31
Separators, reactors and a heat exchanger network (HEN) for heat recovery are important parts of an integrated plant. This thesis deals with the operation of HENs, in particular, optimal operation. The purpose of heat integration is to save energy, but the HEN also introduces new interactions and feedback into the overall plant. A prerequisite for optimisation is that there are extra degrees of freedom left after regulatory control is implemented. It is shown that extra degrees of freedom may not always be utilized for energy optimisation, and a quantitative expression for the degrees of freedom that can be so utilized are presented. A simplified expression that is often valid is also deduced. The thesis presents some improvements and generalisations of a structure based method that has been proposed earlier. Structural information is used to divide possible manipulations into three categories depending on how each manipulation affects the utility consumption. By means of these categories and two heuristic rules for operability, the possible manipulations are ordered in a priority table. This table is used to determine which manipulation should be preferred and which manipulation should be selected if an active manipulation is saturated. It is shown that the method may correspond to split-range control. A method that uses parametric information in addition to structural information is proposed. In this method, the optimal control structure is found through solving an integer programming problem. The thesis also proposes a method that combines the use of steady state optimisation and optimal selection of measurements. 86 refs., 46 figs., 8 tabs.
26 CFR 1.482-5 - Comparable profits method.
2010-04-01
... expenses ordinarily include expenses associated with advertising, promotion, sales, marketing, warehousing... reliability of this profit level indicator increases as operating assets play a greater role in generating.... Financial ratios measure relationships between profit and costs or sales revenue. Since functional...
Optimizing Wellfield Operation in a Variable Power Price Regime
DEFF Research Database (Denmark)
Bauer-Gottwein, Peter; Schneider, Raphael; Davidsen, Claus
2016-01-01
of operating the combined wellfield-storage-demand system over the course of a 2-year planning period based on a time series of observed price on the Danish power market and a deterministic, time-varying hourly water demand. In the SDP setup, hourly pumping rates are the decision variables. Constraints include......-rate pumping benchmark. Minor savings up to 10% were found in the baseline scenario, while the scenario with constant EFP and unlimited pumping rate resulted in savings up to 40%. Key factors determining potential cost savings obtained by flexible wellfield operation under a variable power price regime......Wellfield management is a multiobjective optimization problem. One important objective has been energy efficiency in terms of minimizing the energy footprint (EFP) of delivered water (MWh/m3). However, power systems in most countries are moving in the direction of deregulated markets and price...
Applications of Optimal Building Energy System Selection and Operation
Energy Technology Data Exchange (ETDEWEB)
Marnay, Chris; Stadler, Michael; Siddiqui, Afzal; DeForest, Nicholas; Donadee, Jon; Bhattacharya, Prajesh; Lai, Judy
2011-04-01
Berkeley Lab has been developing the Distributed Energy Resources Customer Adoption Model (DER-CAM) for several years. Given load curves for energy services requirements in a building microgrid (u grid), fuel costs and other economic inputs, and a menu of available technologies, DER-CAM finds the optimum equipment fleet and its optimum operating schedule using a mixed integer linear programming approach. This capability is being applied using a software as a service (SaaS) model. Optimisation problems are set up on a Berkeley Lab server and clients can execute their jobs as needed, typically daily. The evolution of this approach is demonstrated by description of three ongoing projects. The first is a public access web site focused on solar photovoltaic generation and battery viability at large commercial and industrial customer sites. The second is a building CO2 emissions reduction operations problem for a University of California, Davis student dining hall for which potential investments are also considered. And the third, is both a battery selection problem and a rolling operating schedule problem for a large County Jail. Together these examples show that optimization of building u grid design and operation can be effectively achieved using SaaS.
Operational characteristics optimization of human-computer system
Directory of Open Access Journals (Sweden)
Zulquernain Mallick
2010-09-01
Full Text Available Computer operational parameters are having vital influence on the operators efficiency from readability viewpoint. Four parameters namely font, text/background color, viewing angle and viewing distance are analyzed. The text reading task, in the form of English text, was presented on the computer screen to the participating subjects and their performance, measured in terms of number of words read per minute (NWRPM, was recorded. For the purpose of optimization, the Taguchi method is used to find the optimal parameters to maximize operators’ efficiency for performing readability task. Two levels of each parameter have been considered in this study. An orthogonal array, the signal-to-noise (S/N ratio and the analysis of variance (ANOVA were employed to investigate the operators’ performance/efficiency. Results showed that Times Roman font, black text on white background, 40 degree viewing angle and 60 cm viewing distance, the subjects were quite comfortable, efficient and read maximum number of words per minute. Text/background color was dominant parameter with a percentage contribution of 76.18% towards the laid down objective followed by font type at 18.17%, viewing distance 7.04% and viewing angle 0.58%. Experimental results are provided to confirm the effectiveness of this approach.
ENHANCING PROFITABILITY OF A SPINNING
MARSAL Feliu
2014-01-01
Systematic control of the rheological behavior of the ravings in an installation facility dynamometer constant elongation gradient is proposed in this paper. It is an application for all types of spinning both shortfibers as long fibers. Industrial experiments conducted show that this control drawing of the spinning frame is optimized, getting more regular yarns mass with greater industrial profitability. This work is applied to a spinning worsted manufactures fine yarns with high quality ...
Optimizing and controlling earthmoving operations using spatial technologies
Alshibani, Adel
This thesis presents a model designed for optimizing, tracking, and controlling earthmoving operations. The proposed model utilizes, Genetic Algorithm (GA), Linear Programming (LP), and spatial technologies including Global Positioning Systems (GPS) and Geographic Information Systems (GIS) to support the management functions of the developed model. The model assists engineers and contractors in selecting near optimum crew formations in planning phase and during construction, using GA and LP supported by the Pathfinder Algorithm developed in a GIS environment. GA is used in conjunction with a set of rules developed to accelerate the optimization process and to avoid generating and evaluating hypothetical and unrealistic crew formations. LP is used to determine quantities of earth to be moved from different borrow pits and to be placed at different landfill sites to meet project constraints and to minimize the cost of these earthmoving operations. On the one hand, GPS is used for onsite data collection and for tracking construction equipment in near real-time. On the other hand, GIS is employed to automate data acquisition and to analyze the collected spatial data. The model is also capable of reconfiguring crew formations dynamically during the construction phase while site operations are in progress. The optimization of the crew formation considers: (1) construction time, (2) construction direct cost, or (3) construction total cost. The model is also capable of generating crew formations to meet, as close as possible, specified time and/or cost constraints. In addition, the model supports tracking and reporting of project progress utilizing the earned-value concept and the project ratio method with modifications that allow for more accurate forecasting of project time and cost at set future dates and at completion. The model is capable of generating graphical and tabular reports. The developed model has been implemented in prototype software, using Object
What Accounts for Rising Profitability of Chinese Industrial Enterprises?
Institute of Scientific and Technical Information of China (English)
金碚; 李钢
2008-01-01
Based on the latest data, this paper analyses the profitability status of Chinese enterprises and the reasons behind profitability. The authors hold that the profitability of Chinese industrial enterprises has improved significantly whilst the degree of monopolization and extent of entry barriers in the industrial sector has decreased. With the exception of a few resource and administrative monopolizing industries, the increasing profitability of Chinese enterprises indicates rising competitiveness. Improved management level, efficient assets operation, enhanced investment benefits and salary-transfer-profit are all contributing to the profitability of enterprises.
Hierarchical Control for Optimal and Distributed Operation of Microgrid Systems
DEFF Research Database (Denmark)
Meng, Lexuan
of the underlying communication features (sampling time, topology, parameters, etc.). System dynamics and sensitivity analysis are conducted based on the proposed model. A MG central controller is also developed based on the experimental system in the intelligent MG lab in Aalborg University for providing...... are also conducted in order to ensure safe operation during the optimization procedure. In addition, as the secondary and tertiary controls require global information to perform the functions, they are usually implemented in centralized fashion. In this sense the communication links are required from...... the central unit to each local unit, a single point of failure in the central controller may jerpodize the safety of the whole system, and the flexibility of the system is limited. Consequently, this project proposes the application of dynamic consensus algorithm (DCA) into existing hierarchical control...
Optimal operating points of oscillators using nonlinear resonators.
Kenig, Eyal; Cross, M C; Villanueva, L G; Karabalin, R B; Matheny, M H; Lifshitz, Ron; Roukes, M L
2012-11-01
We demonstrate an analytical method for calculating the phase sensitivity of a class of oscillators whose phase does not affect the time evolution of the other dynamic variables. We show that such oscillators possess the possibility for complete phase noise elimination. We apply the method to a feedback oscillator which employs a high Q weakly nonlinear resonator and provide explicit parameter values for which the feedback phase noise is completely eliminated and others for which there is no amplitude-phase noise conversion. We then establish an operational mode of the oscillator which optimizes its performance by diminishing the feedback noise in both quadratures, thermal noise, and quality factor fluctuations. We also study the spectrum of the oscillator and provide specific results for the case of 1/f noise sources.
Energetic optimization of the chilled water systems operation at hotels
Directory of Open Access Journals (Sweden)
Reineris Montero Laurencio
2015-12-01
Full Text Available The hotel exploitation, while continuing to satisfy the customers, needs to decrease the requests of electric power as the principal energy carrier. Solving issues regarding the occupation of a hotel integrally, taking the air conditioning as center of attention, which demands the bigger consumptions of electricity, results in a complex task. To solve this issue, a procedure was implemented to optimize the operation of the water-chilled systems. The procedure integrates an energy model with a strategy of low occupation following energetic criteria based on combinatorial-evolutionary criteria. To classify the information, the formulation of the tasks and the synthesis of the solutions, a methodology of analysis and synthesis of engineering is used. The energetic model considers the variability of the local climatology and the occupation of the selected rooms, and includes: the thermal model of the building obtained by means of artificial neural networks, the hydraulic model and the model of the compression work. These elements allow to find the variable of decision occupation, performing intermediate calculations to obtain the velocity of rotation in the centrifugal pump and the output temperature of the cooler water, minimizing the requirements of electric power in the water-chilled systems. To evaluate the states of the system, a combinatorial optimization is used through the following methods: simple exhaustive, stepped exhaustive or genetic algorithm depending on the quantity of variants of occupation. All calculation tasks and algorithms of the procedure were automated through a computer application.
Installation and first operation of the negative ion optimization experiment
Energy Technology Data Exchange (ETDEWEB)
De Muri, Michela, E-mail: michela.demuri@igi.cnr.it [INFN-LNL, v.le dell’Università 2, I-35020 Legnaro, PD (Italy); Consorzio RFX, CNR, ENEA, INFN, Università di Padova, A cciaierie Venete SpA – Corso Stati Uniti 4, 35127 Padova (Italy); Cavenago, Marco [INFN-LNL, v.le dell’Università 2, I-35020 Legnaro, PD (Italy); Serianni, Gianluigi; Veltri, Pierluigi; Bigi, Marco; Pasqualotto, Roberto; Barbisan, Marco; Recchia, Mauro; Zaniol, Barbara [Consorzio RFX, CNR, ENEA, INFN, Università di Padova, A cciaierie Venete SpA – Corso Stati Uniti 4, 35127 Padova (Italy); Kulevoy, Timour; Petrenko, Sergey [ITEP, B. Cheremushkinskaya 25, 117218 Moscow (Russian Federation); Baseggio, Lucio; Cervaro, Vannino; Agostini, Fabio Degli; Franchin, Luca; Laterza, Bruno [Consorzio RFX, CNR, ENEA, INFN, Università di Padova, A cciaierie Venete SpA – Corso Stati Uniti 4, 35127 Padova (Italy); Minarello, Alessandro [INFN-LNL, v.le dell’Università 2, I-35020 Legnaro, PD (Italy); Rossetto, Federico [Consorzio RFX, CNR, ENEA, INFN, Università di Padova, A cciaierie Venete SpA – Corso Stati Uniti 4, 35127 Padova (Italy); Sattin, Manuele [INFN-LNL, v.le dell’Università 2, I-35020 Legnaro, PD (Italy); Zucchetti, Simone [Consorzio RFX, CNR, ENEA, INFN, Università di Padova, A cciaierie Venete SpA – Corso Stati Uniti 4, 35127 Padova (Italy)
2015-10-15
Highlights: • Negative ion sources are key components of the neutral beam injectors. • The NIO1 experiment is a RF ion source, 60 kV–135 mA hydrogen negative ion beam. • NIO1 can contribute to beam extraction and optics thanks to quick replacement and upgrading of parts. • This work presents installation, status and first experiments results of NIO1. - Abstract: Negative ion sources are key components of the neutral beam injectors for thermonuclear fusion experiments. The NIO1 experiment is a radio frequency ion source generating a 60 kV–135 mA hydrogen negative ion beam. The beam is composed of nine beamlets over an area of about 40 × 40 mm{sup 2}. This experiment is jointly developed by Consorzio RFX and INFN-LNL, with the purpose of providing and optimizing a test ion source, capable of working in continuous mode and in conditions similar to those foreseen for the larger ion sources of the ITER neutral beam injectors. At present research and development activities on these ion sources still address several important issues related to beam extraction and optics optimization, to which the NIO1 test facility can contribute thanks to its modular design, which allows for quick replacement and upgrading of components. This contribution presents the installation phases, the status of the test facility and the results of the first experiments, which have demonstrated that the source can operate in continuous mode.
Directory of Open Access Journals (Sweden)
B. Thamaraikannan
2014-01-01
Full Text Available This paper studies in detail the background and implementation of a teaching-learning based optimization (TLBO algorithm with differential operator for optimization task of a few mechanical components, which are essential for most of the mechanical engineering applications. Like most of the other heuristic techniques, TLBO is also a population-based method and uses a population of solutions to proceed to the global solution. A differential operator is incorporated into the TLBO for effective search of better solutions. To validate the effectiveness of the proposed method, three typical optimization problems are considered in this research: firstly, to optimize the weight in a belt-pulley drive, secondly, to optimize the volume in a closed coil helical spring, and finally to optimize the weight in a hollow shaft. have been demonstrated. Simulation result on the optimization (mechanical components problems reveals the ability of the proposed methodology to find better optimal solutions compared to other optimization algorithms.
PROFIT – THE ABSOLUTE EXPRESSION OF PROFITABILITY
Directory of Open Access Journals (Sweden)
Daniela SIMTION
2013-12-01
Full Text Available Profitability of an economic unit is expressed through a system of indicators, because "no index or economic category can reflect the total, perfect, complex reality of economic phenomena or processes. Each expresses a side of concrete, essential details (indexes, but a full one (economic category. This system of indexes for profitability is characterized by a higher degree of consolidation, of reflection of the economic-financial results. They must be correlated to the other indexes of economic efficiency from the various subsystems that constitute the factors which determine the actual amount of profit and the rate of return. Each indicator has a certain form of expression according to the phenomena to which it refers. Thus, they can be expressed in relative sizes as medium sizes or indexes. They can also be expressed in physical, conventional or value units. The ability to develop monetary results can not be judged independently to the employed means for achieving them. Therefore, the profitability analysis is not limited to investigating its absolute indexes but also the relative ones, obtained by comparing the results to the means employed or consumed for developing the specific activity
PROFITABILITY AND SIZE OF FIRM.
Contents: The profit ratio as a measure of the relative ability of firms to expand; the profit dratio as a measure of efficiency; other uses of the... profit ratio; earlier studies using the profit ratio; valid conclusions of earlier studies; assets vs. net worth; methodology of this study...distribution of post-tax profit ratex; effect of taxes on the relative ability to expand; relative profitability of income firms; variability of profit rates
DEFF Research Database (Denmark)
2016-01-01
DataProfit er et værktøj til at kortlægge og analysere din virksomheds evne til datadreven forretningsudvikling.......DataProfit er et værktøj til at kortlægge og analysere din virksomheds evne til datadreven forretningsudvikling....
Management trends: Internationalization of non-profit organizations
Directory of Open Access Journals (Sweden)
Inić Branimir P.
2015-01-01
Full Text Available Non-profit organizations are increasingly gaining importance in the modern economy with their development and their numbers increasing day by day. It is very important to note that non-profit organizations are often subject to various benefits that the for-profit companies are not. Thus, for example, preferential tax status of non-profit organizations is manifested primarily in the form of exemption from corporate income tax. In addition, private non-profit organizations enjoy various other state, local and federal taxes exemptions. Under certain conditions, these organizations are exempt from taxes on donations and membership fees. A feature that differentiates various non-profit organizations and profit-oriented companies is their source of income. Profit oriented companies depend on their income, obtained from sales of their goods or services to customers, who usually cover the price and cost of goods and services plus the profit. In contrast, nonprofit organizations are very dependent on membership fees, tax exemptions, members donations or depend on funds of the sponsoring agency which covers most of their costs, for example a federal government agency. Those non-profit organizations that have substantial operating costs beyond national borders and do not identify themselves as purely domestic in their mandate are International non-profit organizations. Most non-profit organizations remain in their national boundaries, on the territory of the country in which they were created, but a large number of non-profit organizations rapidly internationalize, and some larger non-profits have grown into important global actors. The paper includes the following sections: (1 introduction, (2 why is the 'non-profit' important, (3 the internationalization of non-profit organizations, (4 sources of income of non-profit organizations (4.1. causality of impact and of strategic decisions in cases pertaining to universities, (5 the limits of strategic
Energy Technology Data Exchange (ETDEWEB)
Bjoerndal, Mette; Joernsten, Kurt
2001-08-01
This report evaluates the possible profits of establishing a common system operator function in the Nordic electric power market. The main focus is placed on how to deal with congestion in the transmission grid. To estimate possible profits from a better utilization of the resources in the Nordic grid, the authors have analyzed socio-economic profits for several load scenarios. A simplified model of the Nordic stock area was used in the calculations. The existence of two methods of dealing with congestion in the grid may lead to reduced capacity utilization and to greater price differences than necessary. The examples show that ''indirect'' congestion control may be very expensive and that considerable cost reduction can be achieved by improved exploitation of congestion. This implies that if the Nordic area is divided into price zones, it is advantageous to regard the grid as an entity independent of national borders and system operators and to let the real transmission limitations determine the price zoning.
Optimal Protection Coordination for Microgrid under Different Operating Modes
Directory of Open Access Journals (Sweden)
Ming-Ta Yang
2013-01-01
Full Text Available Significant consequences result when a microgrid is connected to a distribution system. This study discusses the impacts of bolted three-phase faults and bolted single line-to-ground faults on the protection coordination of a distribution system connected by a microgrid which operates in utility-only mode or in grid-connected mode. The power system simulation software is used to build the test system. The linear programming method is applied to optimize the coordination of relays, and the relays coordination simulation software is used to verify if the coordination time intervals (CTIs of the primary/backup relay pairs are adequate. In addition, this study also proposes a relays protection coordination strategy when the microgrid operates in islanding mode during a utility power outage. Because conventional CO/LCO relays are not capable of detecting high impedance fault, intelligent electrical device (IED combined with wavelet transformer and neural network is proposed to accurately detect high impedance fault and identify the fault phase.
DEFF Research Database (Denmark)
Bingley, Paul; Westergård-Nielsen, Niels Chr.
2004-01-01
personnel structure variation. It is found that personnel policy is strongly related to economic performance. At the margin, more hires are associated with lower profit, and more separations with higher profit. For the average firm, one new job, all else equal, is associated with ?2680 (2000 prices) lower......There is a growing awareness of large differences in worker turnover and pay between firms. However, there is little knowledge about the effects of this on firm performance. This paper describes how personnel policies with respect to pay, tenure and worker flows are related to economic performance...... annual profit. Higher wage level and lower wage growth is associated with higher profit. A workforce that has less tenure, all else equal, is more profitable....
Optimizing Wind And Hydropower Generation Within Realistic Reservoir Operating Policy
Magee, T. M.; Clement, M. A.; Zagona, E. A.
2012-12-01
Previous studies have evaluated the benefits of utilizing the flexibility of hydropower systems to balance the variability and uncertainty of wind generation. However, previous hydropower and wind coordination studies have simplified non-power constraints on reservoir systems. For example, some studies have only included hydropower constraints on minimum and maximum storage volumes and minimum and maximum plant discharges. The methodology presented here utilizes the pre-emptive linear goal programming optimization solver in RiverWare to model hydropower operations with a set of prioritized policy constraints and objectives based on realistic policies that govern the operation of actual hydropower systems, including licensing constraints, environmental constraints, water management and power objectives. This approach accounts for the fact that not all policy constraints are of equal importance. For example target environmental flow levels may not be satisfied if it would require violating license minimum or maximum storages (pool elevations), but environmental flow constraints will be satisfied before optimizing power generation. Additionally, this work not only models the economic value of energy from the combined hydropower and wind system, it also captures the economic value of ancillary services provided by the hydropower resources. It is recognized that the increased variability and uncertainty inherent with increased wind penetration levels requires an increase in ancillary services. In regions with liberalized markets for ancillary services, a significant portion of hydropower revenue can result from providing ancillary services. Thus, ancillary services should be accounted for when determining the total value of a hydropower system integrated with wind generation. This research shows that the end value of integrated hydropower and wind generation is dependent on a number of factors that can vary by location. Wind factors include wind penetration level
Canning, Patricia M.; Lyon, Mary E.; Kienapple, Kim; Young, Jeffrey
2002-01-01
Examined how Canadian day care centers are operated and managed, to identify differences in organizational structure and behavior between non-profit and for-profit centers and characteristics of structure and management linked with high quality care. Found that non-profit centers were more complex, more formalized, and less centralized than…
Factors Affecting Profitability of Layer Hens Enterprises
Directory of Open Access Journals (Sweden)
Ebraheem Altahat
2012-01-01
Full Text Available Problem statement: Layer hen enterprises suffer from low profitability or losses in many of developing countries all over the world. Jordan is not an acceptance. Approach: This study aimed at investigating the influence of ten main factors affecting the profitability of layer hen producers. The investigated factors include price of purchased pullet, feed price, cost of labor, cost of veterinary service and medicine, building and machinery depreciation, repairs and maintenance and miscellaneous costs, length of production cycle, feed conversion ratio, mortality rate, egg sale price and laying percentage. Results: The study used a multiple regression profit model to estimate the effect of the above mentioned factors on profit per kg egg produced. The direction and quantity of relationship between profit per kg egg and variables affecting profit were investigated. Data from 40 operating and randomly selected egg production enterprises in the country was collected. Data was obtained directly from the producers during April to mid August 2010. Semi structured interviews were conducted with a pre-tested questionnaire. The data obtained via interview surveys were processed to calculate profit per kg egg and other relevant information for inclusion in a profit function model. Fifteen eggs are registered to be 1 kg in the study. Cost and income items used to calculate profit in the study. The results of the study revealed that the feed price was found to be the factor which has the highest negative impact on the profitability showing the coefficient-3.01. The egg sale price was with high positive impact on profitability showing the coefficient 2.633. Conclusion/Recommendations: From the results of the study it could be concluded that higher prices of purchased or breeding pullet, higher feed price, higher cost of labor, higher cost of veterinary service and medicine, higher other costs including building and machinery depreciation, repairs and
Chemically optimizing operational efficiency of molecular rotary motors.
Conyard, Jamie; Cnossen, Arjen; Browne, Wesley R; Feringa, Ben L; Meech, Stephen R
2014-07-09
Unidirectional molecular rotary motors that harness photoinduced cis-trans (E-Z) isomerization are promising tools for the conversion of light energy to mechanical motion in nanoscale molecular machines. Considerable progress has been made in optimizing the frequency of ground-state rotation, but less attention has been focused on excited-state processes. Here the excited-state dynamics of a molecular motor with electron donor and acceptor substituents located to modify the excited-state reaction coordinate, without altering its stereochemistry, are studied. The substituents are shown to modify the photochemical yield of the isomerization without altering the motor frequency. By combining 50 fs resolution time-resolved fluorescence with ultrafast transient absorption spectroscopy the underlying excited-state dynamics are characterized. The Franck-Condon excited state relaxes in a few hundred femtoseconds to populate a lower energy dark state by a pathway that utilizes a volume conserving structural change. This is assigned to pyramidalization at a carbon atom of the isomerizing bridging double bond. The structure and energy of the dark state thus reached are a function of the substituent, with electron-withdrawing groups yielding a lower energy longer lived dark state. The dark state is coupled to the Franck-Condon state and decays on a picosecond time scale via a coordinate that is sensitive to solvent friction, such as rotation about the bridging bond. Neither subpicosecond nor picosecond dynamics are sensitive to solvent polarity, suggesting that intramolecular charge transfer and solvation are not key driving forces for the rate of the reaction. Instead steric factors and medium friction determine the reaction pathway, with the sterically remote substitution primarily influencing the energetics. Thus, these data indicate a chemical method of optimizing the efficiency of operation of these molecular motors without modifying their overall rotational frequency.
Optimizing Wellfield Operation in a Variable Power Price Regime.
Bauer-Gottwein, Peter; Schneider, Raphael; Davidsen, Claus
2016-01-01
Wellfield management is a multiobjective optimization problem. One important objective has been energy efficiency in terms of minimizing the energy footprint (EFP) of delivered water (MWh/m(3) ). However, power systems in most countries are moving in the direction of deregulated markets and price variability is increasing in many markets because of increased penetration of intermittent renewable power sources. In this context the relevant management objective becomes minimizing the cost of electric energy used for pumping and distribution of groundwater from wells rather than minimizing energy use itself. We estimated EFP of pumped water as a function of wellfield pumping rate (EFP-Q relationship) for a wellfield in Denmark using a coupled well and pipe network model. This EFP-Q relationship was subsequently used in a Stochastic Dynamic Programming (SDP) framework to minimize total cost of operating the combined wellfield-storage-demand system over the course of a 2-year planning period based on a time series of observed price on the Danish power market and a deterministic, time-varying hourly water demand. In the SDP setup, hourly pumping rates are the decision variables. Constraints include storage capacity and hourly water demand fulfilment. The SDP was solved for a baseline situation and for five scenario runs representing different EFP-Q relationships and different maximum wellfield pumping rates. Savings were quantified as differences in total cost between the scenario and a constant-rate pumping benchmark. Minor savings up to 10% were found in the baseline scenario, while the scenario with constant EFP and unlimited pumping rate resulted in savings up to 40%. Key factors determining potential cost savings obtained by flexible wellfield operation under a variable power price regime are the shape of the EFP-Q relationship, the maximum feasible pumping rate and the capacity of available storage facilities.
A systematic approach: optimization of healthcare operations with knowledge management.
Wickramasinghe, Nilmini; Bali, Rajeev K; Gibbons, M Chris; Choi, J H James; Schaffer, Jonathan L
2009-01-01
Effective decision making is vital in all healthcare activities. While this decision making is typically complex and unstructured, it requires the decision maker to gather multispectral data and information in order to make an effective choice when faced with numerous options. Unstructured decision making in dynamic and complex environments is challenging and in almost every situation the decision maker is undoubtedly faced with information inferiority. The need for germane knowledge, pertinent information and relevant data are critical and hence the value of harnessing knowledge and embracing the tools, techniques, technologies and tactics of knowledge management are essential to ensuring efficiency and efficacy in the decision making process. The systematic approach and application of knowledge management (KM) principles and tools can provide the necessary foundation for improving the decision making processes in healthcare. A combination of Boyd's OODA Loop (Observe, Orient, Decide, Act) and the Intelligence Continuum provide an integrated, systematic and dynamic model for ensuring that the healthcare decision maker is always provided with the appropriate and necessary knowledge elements that will help to ensure that healthcare decision making process outcomes are optimized for maximal patient benefit. The example of orthopaedic operating room processes will illustrate the application of the integrated model to support effective decision making in the clinical environment.
Studies on optimal design and operation of integrated distillation arrangements
Energy Technology Data Exchange (ETDEWEB)
Christiansen, Atle Christer
1997-12-31
During the last decades, there has been growing concern in the chemical engineering environment over the task of developing more cost- and energy efficient process equipment. This thesis discusses measures for improving the end-use energy efficiency of separation systems. It emphasises a certain class of integrated distillation arrangements, in particular it considers means for direct coupling of distillation columns so as to use the underlying physics to facilitate more energy efficient separations. The numerical methods discussed are well suited to solve models of distillation columns. A tear and grid method is proposed that to some extent exploits the sparsity, since the number of tear variables required for solving a distillation model usually is rather small. The parameter continuation method described is well suited for ill-conditioned problems. The analysis of integrated columns is extended beyond the scope of numerical simulations by means of analytical results that applies in certain limiting cases. The consept of preferred separation, which is important for prefractionator arrangements, is considered. From this analysis is derived information that is important for the practical operation of such columns. Finally, the proposed numerical methods are used to optimize Petlyuk arrangements for separating ternary and quaternary mixtures. 166 refs., 130 figs., 20 tabs.
Li/CFx Cells Optimized for Low-Temperature Operation
Smart, Marshall C.; Whitacre, Jay F.; Bugga, Ratnakumar V.; Prakash, G. K. Surya; Bhalla, Pooja; Smith, Kiah
2009-01-01
Some developments reported in prior NASA Tech Briefs articles on primary electrochemical power cells containing lithium anodes and fluorinated carbonaceous (CFx) cathodes have been combined to yield a product line of cells optimized for relatively-high-current operation at low temperatures at which commercial lithium-based cells become useless. These developments have involved modifications of the chemistry of commercial Li/CFx cells and batteries, which are not suitable for high-current and low-temperature applications because they are current-limited and their maximum discharge rates decrease with decreasing temperature. One of two developments that constitute the present combination is, itself, a combination of developments: (1) the use of sub-fluorinated carbonaceous (CFx wherein xLiBF4 dissolved at a concentration of 0.5 M in a mixture of four volume parts of 1,2 dimethoxyethane with one volume part of propylene carbonate. The proportion, x, of fluorine in the cathode in such a cell lies between 0.5 and 0.9. The best of such cells fabricated to date have exhibited discharge capacities as large as 0.6 A h per gram at a temperature of 50 C when discharged at a rate of C/5 (where C is the magnitude of the current, integrated for one hour, that would amount to the nominal charge capacity of a cell).
Directory of Open Access Journals (Sweden)
Woraya Neungmatcha
2015-06-01
Full Text Available Since current agricultural production systems such as the sugarcane supply system in the sugar industry are developing towards larger and more complicated systems, there is consequently increasing use of agricultural machinery. Even though mechanization can help to increase the sugarcane yield, if the mechanical operation efficiency is low, then higher harvest costs and machinery shortages will occur. Global route planning for mechanical harvesters is one of the most important problems in the field of sugarcane harvesting and transporting operations. Improved efficiency and realistic implementation can be achieved by applying advanced planning methods for the execution of field operations, especially considering the field accessibility aspect. To address this issue, participative research was undertaken with a sugar milling company to produce and implement a mixed integer programming model that represents the mechanical harvester route plan. Particle swarm optimization was applied to find a solution to the model, leading to potential cost savings versus schedules produced manually by the mill officer. The model was also applied to explore regional planning options for a more integrated harvesting and transport system.
Marketing to maximize profitability.
Duboff, R S
1992-01-01
An effective marketing strategy should focus on serving profitable customers, not just adding new ones. The author offers five steps that marketers can follow to ensure that their efforts provide the greatest boost to the bottom line.
Fractal profit landscape of the stock market.
Grönlund, Andreas; Yi, Il Gu; Kim, Beom Jun
2012-01-01
We investigate the structure of the profit landscape obtained from the most basic, fluctuation based, trading strategy applied for the daily stock price data. The strategy is parameterized by only two variables, p and q Stocks are sold and bought if the log return is bigger than p and less than -q, respectively. Repetition of this simple strategy for a long time gives the profit defined in the underlying two-dimensional parameter space of p and q. It is revealed that the local maxima in the profit landscape are spread in the form of a fractal structure. The fractal structure implies that successful strategies are not localized to any region of the profit landscape and are neither spaced evenly throughout the profit landscape, which makes the optimization notoriously hard and hypersensitive for partial or limited information. The concrete implication of this property is demonstrated by showing that optimization of one stock for future values or other stocks renders worse profit than a strategy that ignores fluctuations, i.e., a long-term buy-and-hold strategy.
Fractal profit landscape of the stock market.
Directory of Open Access Journals (Sweden)
Andreas Grönlund
Full Text Available We investigate the structure of the profit landscape obtained from the most basic, fluctuation based, trading strategy applied for the daily stock price data. The strategy is parameterized by only two variables, p and q Stocks are sold and bought if the log return is bigger than p and less than -q, respectively. Repetition of this simple strategy for a long time gives the profit defined in the underlying two-dimensional parameter space of p and q. It is revealed that the local maxima in the profit landscape are spread in the form of a fractal structure. The fractal structure implies that successful strategies are not localized to any region of the profit landscape and are neither spaced evenly throughout the profit landscape, which makes the optimization notoriously hard and hypersensitive for partial or limited information. The concrete implication of this property is demonstrated by showing that optimization of one stock for future values or other stocks renders worse profit than a strategy that ignores fluctuations, i.e., a long-term buy-and-hold strategy.
Combining Purpose With Profits
DEFF Research Database (Denmark)
Julian Birkinshaw, Julian; Foss, Nicolai Juul; Lindenberg, Siegwart
2014-01-01
A sense of purpose that transcends making money can motivate employees. But to sustain both a sense of purpose and a solid level of profitability over time, companies need to pay attention to several fundamental organizing principles.......A sense of purpose that transcends making money can motivate employees. But to sustain both a sense of purpose and a solid level of profitability over time, companies need to pay attention to several fundamental organizing principles....
Combining Purpose With Profits
DEFF Research Database (Denmark)
Julian Birkinshaw, Julian; Foss, Nicolai Juul; Lindenberg, Siegwart
2014-01-01
A sense of purpose that transcends making money can motivate employees. But to sustain both a sense of purpose and a solid level of profitability over time, companies need to pay attention to several fundamental organizing principles.......A sense of purpose that transcends making money can motivate employees. But to sustain both a sense of purpose and a solid level of profitability over time, companies need to pay attention to several fundamental organizing principles....
Client selection strategy of service profit optimization%服务计算环境中收益优化的客户选择策略
Institute of Scientific and Technical Information of China (English)
刘蓉; 李红艳; 杨长兴
2012-01-01
提出一种综合考虑长期收益的客户选择策略,即在选择客户时,依据与客户的交互情况,依据客户的潜在长期价值作为其选择的标准.而客户的潜在价值是依据其交互的历史情况、可信程度和活跃程度进行计算.将这些参数作为客户长期价值的评价参数,综合给出接纳客户服务请求的收益计算方法以及不接纳客户可能造成的损失方法,从而给出综合优化的客户选择方法.研究结果表明:与传统的仅以当前收益最大化的优化方法相比,本文的策略在长期收益要高30％以上,而且考察的时间越长,策略的效果越明显,证明了本文策略的优越性.%A customer selection strategy with comprehensive long-term gains was put forward. The procedures are as follows. The selection criteria is based on the interaction and potential long-term value of the customer. The potential value of the customer is calculated according to his interaction history, credibility and active level. These parameters are selected as evaluation parameters for customer's long-term value calculation, and then the profit calculation method accepting the customer service requests as well as the loss calculation method of rejecting service requests are given. The results show that, compared with traditional methods which only focus on current profit maximization, mis strategy is better in the long-term profit by more than 30%, and the longer inspection, the more obvious effects can be obtained, which indicates the superiority of the strategy.
Economic feasibility of reequipment terms based on profitability criterion
Directory of Open Access Journals (Sweden)
D.V. Bezugla
2015-03-01
, that influence the increase or decrease of the coefficient of equipment suitability; quality of all kinds of repair – prophylactic work, qualification level of personnel carrying out the machine – tools and technological equipment exploitation, acceptability to conditions of it usage. To affect the influence of indicated factors it may be proposed to put into operation modification coefficient of obsolescence and production suitability of basic production assets, being established by the expert valuation method. To fulfill the expert examination of production system an expert group is formed, and every expert gives his grade on a ten-mark scale for six influences – factor groups to every object of appraisal. The next algorithm step is calculation the coefficient of modification by using of indices received from experts. As a result of completed expert examination the mentioned coefficient can change values of equipment obsolescence and production suitability according to real industry conditions being often distinct from the industry standard methods of it determination. Consequently for offering of improved approach it may be proposed formula for a priori calculation the value of economic profit obtained to use at dynamic optimization method: Pi(t = R∙G1(t∙[Kм(WAi(t]∙S1(t∙(1 + і∙KІН. Its components are: R – production profitability; Gi(t – initial equipment productivity; Kм(WAi(t – modified coefficient of production suitability; S1(t – initial product cost; KІН – coefficient of annual inflation; t – equipment exploitation age; i – the index of any present year of the equipment exploitation period. Simultaneously a new approach may be offered to use a priori calculated profit value, obtained by exploitation of technological equipment. It consists in division of considered profit value Pi(t into two components: the first part of profit value P(CURi(t will be turned to the present – day needs (for example to equipment repair, and
Institute of Scientific and Technical Information of China (English)
李进华; 王雪生; 邢元; 王树新; 李建民; 梁科
2016-01-01
To evaluate the operation comfortability in the master-slave robotic minimally invasive surgery (MIS), an optimal function was built with two operation comfortability decided indices, i.e., the center distance and volume contact ratio. Two verifying experiments on Phantom Desktop and MicroHand S were conducted. Experimental results show that the operation effect at the optimal relative location is better than that at the random location, which means that the optimal function constructed in this paper is effective in optimizing the operation comfortability.
Profitability of wood harvesting enterprises
Energy Technology Data Exchange (ETDEWEB)
Penttinen, M. email: markku.penttinen@metla.fi; Mikkola, J. email: jarmo.mikkola@metla.fi; Rummukainen, A. email: arto.rummukainen@metla.fi
2009-07-01
The forest machine business is about 50 years old. The rapid technical development of machinery increased productivity up to the end of last century. In 2007, the total value of round and energy wood harvesting and silvicultural work operated by forest machine enterprises exceeded 570 mill. euro. According to the materials of the Vehicle Administration Finland and Statistics Finland there are about 1 600 active harvesting enterprises in the personal and business taxation system. Beside this, there are according to the Ministry of Agriculture and Forestry about 1 300 farmers who do harvesting as side business. About 1 000 enterprises working in June 2007 were studied with their retrospective economic analyses from 2001. The data includes all enterprises that had supplied closing of the accounts data. One-machine entrepreneurs represent more than a third of the number of enterprises, but only 13 percent of the turnover. Enterprises with seven or more machines represent less than ten percent of the number, but over twenty percent of the turnover. Enterprises are largest in eastern and northern Finland, where the average number of machines per enterprise exceeds three. Small enterprises are mostly singleowner business enterprises with a median turnover of 125 000 euros per annum. Partnerships and limited enterprises have double the median turnover of single-owner businesss. Limited companies turn over a median of 450 000 euro/y, representing 67 percent of total turnover. Median net profit varied between 6 and 10 percent of turnover in 2001-2007, but only between 2 and 4 percent where the wage adjustment is deducted from the profit. The wage adjustment is estimated as if the owners of single-owner businesses earn an operator's salary. Profit was highest in 2002 and lowest 2006. In the smallest enterprise class with a turnover of less than 75 000 euro/y, profit was lowest and negative in 2006 and 2007. The variation in profits between enterprises was also biggest in
The method of optimization of neuro-based concurrent operations in neurocomputers
Romanchuk, V. A.
2017-02-01
The article deals with the task of optimization of neuro-based concurrent operations to be implemented in neurocomputers. We define mathematical tools of this optimization that can employ the set-theoretic approach towards such concepts as task, operation, and microcommand. We consider segmentation and parallelization of operations as methods to use, depending on precedence relations among operations that constitute these segments. The task solution of optimization of neuro-based concurrent operations in neurocomputers can be applied to a whole class of neurocomputers, regardless of the manufacturer, the model or the product line, since we only address the general properties and principles of the neurocomputer operation. We select criteria and define methods of evaluating the effectiveness of parallelization of concurrent operations, when they are implemented in neurocomputers. We describe our empiric research in the form of a software system that automatically optimizes neuro-based concurrent operations in neurocomputers on the NP Studio platform.
Profit Allocation of PPP Model Based on the Revised SHAPELY%基于SHAPELY修正的PPP项目利益分配模型研究
Institute of Scientific and Technical Information of China (English)
胡丽; 张卫国; 叶晓甦
2011-01-01
The labor socialization is a primary concern for companies operating in a rapidly growing market. A large-scale engineering project often involves complex labor socialization processes and imbalance of profit distribution among participants. Unbalanced profit distribution can cause unrest of labor socialization. It is imperative to quantify labor socialization and profit distribution and use the information as a guide for project execution. Public-private partnership (PPP) projects involve complex financing and construction structures (e. g. long construction duration, high investment, large construction scale, contract complexity and operational uncertainty ).The nature of financial and construction complexity has the potential of creating imbalance of profit distribution, thereby causing the failure of project execution. Hence, it is important to coordinate and eliminate the profit conflict between private and public sections. This paper proposes a profit allocation model to help coordinate profit allocation and maximize profits for both private and public sectors based on basic principles of project profit allocation. The proposed model includes four key factors: investment ratio,risk share coefficient, and the degree of contract completion and profit contribution.We conducted a numerical analysis to assess the correctness of the proposed model. We also compared profits of a PPP project with profits of projects delivered independently by either private or public sector.Our comparison results showed that the former project's profit is higher than the latter project's profit. These findings indicate that the proposed profit allocation model can optimize profits for both public and private sectors.It is practical to apply the proposed research model to maximize profits for participants involved in PPP projects.%PPP涉及多方利益主体,出于自身利益考虑,可能出现有损合作伙伴利益的行为,导致PPP项目实施的失败.因此,解决公私双方
Afshar, Abbas; Emami Skardi, Mohammad J.; Masoumi, Fariborz
2015-09-01
Efficient reservoir management requires the implementation of generalized optimal operating policies that manage storage volumes and releases while optimizing a single objective or multiple objectives. Reservoir operating rules stipulate the actions that should be taken under the current state of the system. This study develops a set of piecewise linear operating rule curves for water supply and hydropower reservoirs, employing an imperialist competitive algorithm in a parameterization-simulation-optimization approach. The adaptive penalty method is used for constraint handling and proved to work efficiently in the proposed scheme. Its performance is tested deriving an operation rule for the Dez reservoir in Iran. The proposed modelling scheme converged to near-optimal solutions efficiently in the case examples. It was shown that the proposed optimum piecewise linear rule may perform quite well in reservoir operation optimization as the operating period extends from very short to fairly long periods.
Institute of Scientific and Technical Information of China (English)
袁钰斐
2012-01-01
Different from previous research ,the article assigns 15 listed banks into large -scale banks, medium - scale banks, and small banks according to their average asset size. This paper investigates the effects of revenue diversification on the profitability and risk of the Chinese banking industry. Using the sample which consists of 15 listed banks during the year of 2000 -2011, we find that increased engagement in noninterest activities is associated with higher profitability without affecting the risk. And benefits from diversification can only be seized optimally by small banks. Higher Fee - based income is associated with higher profitability and lower risk.%不同于以往研究，文章将15家上市银行按照平均资产规模大小分成大规模银行、中等规模银行、小规模银行采用2000年-2011年的数据建立面板数据模型，分析我国商业银行非利息收入及其组成部分占营业收入比重的变化对银行收益和风险的影响。结果表明，非利息收入占比的提高对银行的收益有正效应，且这种效应在小规模银行中更为明显。非利息收入占比与银行风险的关系总体并不显著，但对大规模银行来说有一定的降低风险效应。手续费及佣金收入占比的提高会增加银行的收益并降低风险。
Study of operation optimization based on data mining technique in power plants
Institute of Scientific and Technical Information of China (English)
LI Jianqiang; LIU Jizhen; GU Junjie; NIU Chenglin
2007-01-01
The determination of operation optimization value is very important for economic analysis and operation optimization in power plants.The operation optimization value determined by traditional methods usually cannot reflect the actual running states correctly in power plants with the increase in running time.Based on a large amount of history data stored in power plants,a way of operation optimization by applying data mining technique is proposed.The structure of operation optimi-zation based on data mining is established and the fuzzy association rule mining algorithm is introduced to find the operation optimization target value to guide the operation in power plants.Based on the actual local data in a 300 MW unit,the operation optimization value in typical load ranges is found out by data mining to provide better adjustment guidance in industry process.Experimental results show that the determination of operation optimization value based on data mining can improve the efficiency and decrease the emission of pollutants.
Financialization and financial profit
Directory of Open Access Journals (Sweden)
Arturo Guillén
2014-09-01
Full Text Available This article starts from the critical review of the concept of financial capital. I consider it is necessary not to confuse this category with of financialization, which has acquired a certificate of naturalization from the rise of neoliberalism. Although financial monopoly-financial capital is the hegemonic segment of the bourgeoisie in the major capitalist countries, their dominance does not imply, a fortiori, financialization of economic activity, since it depends of the conditions of the process reproduction of capital. The emergence of joint stock companies modified the formation of the average rate of profit. The "promoter profit" becomes one of the main forms of income of monopoly-financial capital. It is postulated that financial profit is a kind of "extraordinary surplus-value" which is appropriated by monopoly-financial capital by means of the monopolistic control it exerts on the issue and circulation of fictitious capital.
Refrigerator Optimal Scheduling to Minimise the Cost of Operation
Directory of Open Access Journals (Sweden)
Bálint Roland
2016-12-01
Full Text Available The cost optimal scheduling of a household refrigerator is presented in this work. The fundamental approach is the model predictive control methodology applied to the piecewise affine model of the refrigerator.
THE INTERACTION OF WORKING CAPITAL MANAGEMENT AND PROFITABILITY MEASURES
Yilmaz, İlker
2015-01-01
In this article, the interaction between working capital management success and different measures of profitability was examined. When components of net working capital are kept at optimal levels, this situation benefits company to use resources more efficiently and helps profitability. Similarly, high levels of profitability helps avoiding idle working capital practices. By using a sample consisting of 172 non-financial companies traded Borsa Istanbul (BIST) in Turkey, and 5-year data coveri...
RFM customer profitability analysis
Directory of Open Access Journals (Sweden)
Marinković Veljko
2008-01-01
Full Text Available Measuring the customer profitability is a very important activity for each and every modern marketing oriented firm. By identifying profitable customer segments, the efficiency and the effectiveness of the marketing strategies can be significantly improved. One of the best-known methods for identifying the most valuable customers is the RFM method. The application of this method is particularly important in the decision-making process related to justification of the application of the various direct marketing strategies, and especially when the introduction of the new product into the market is the key issue.
Nested algorithms for optimal reservoir operation and their embedding in a decision support platform
Delipetrev, B.
2016-01-01
Reservoir operation is a multi-objective optimization problem traditionally solved with dynamic programming (DP) and stochastic dynamic programming (SDP) algorithms. The thesis presents novel algorithms for optimal reservoir operation named nested DP (nDP), nested SDP (nSDP), nested reinforcement le
Average optimization of the approximate solution of operator equations and its application
Institute of Scientific and Technical Information of China (English)
WANG; xinghua(王兴华); MA; Wan(马万)
2002-01-01
In this paper, a definition of the optimization of operator equations in the average case setting is given. And the general result (Theorem 1) about the relevant optimization problem is obtained. This result is applied to the optimization of approximate solution of some classes of integral equations.
Pricing Resources in LTE Networks through Multiobjective Optimization
Directory of Open Access Journals (Sweden)
Yung-Liang Lai
2014-01-01
Full Text Available The LTE technology offers versatile mobile services that use different numbers of resources. This enables operators to provide subscribers or users with differential quality of service (QoS to boost their satisfaction. On one hand, LTE operators need to price the resources high for maximizing their profits. On the other hand, pricing also needs to consider user satisfaction with allocated resources and prices to avoid “user churn,” which means subscribers will unsubscribe services due to dissatisfaction with allocated resources or prices. In this paper, we study the pricing resources with profits and satisfaction optimization (PRPSO problem in the LTE networks, considering the operator profit and subscribers' satisfaction at the same time. The problem is modelled as nonlinear multiobjective optimization with two optimal objectives: (1 maximizing operator profit and (2 maximizing user satisfaction. We propose to solve the problem based on the framework of the NSGA-II. Simulations are conducted for evaluating the proposed solution.
Pricing resources in LTE networks through multiobjective optimization.
Lai, Yung-Liang; Jiang, Jehn-Ruey
2014-01-01
The LTE technology offers versatile mobile services that use different numbers of resources. This enables operators to provide subscribers or users with differential quality of service (QoS) to boost their satisfaction. On one hand, LTE operators need to price the resources high for maximizing their profits. On the other hand, pricing also needs to consider user satisfaction with allocated resources and prices to avoid "user churn," which means subscribers will unsubscribe services due to dissatisfaction with allocated resources or prices. In this paper, we study the pricing resources with profits and satisfaction optimization (PRPSO) problem in the LTE networks, considering the operator profit and subscribers' satisfaction at the same time. The problem is modelled as nonlinear multiobjective optimization with two optimal objectives: (1) maximizing operator profit and (2) maximizing user satisfaction. We propose to solve the problem based on the framework of the NSGA-II. Simulations are conducted for evaluating the proposed solution.
Multi-objective reservoir operation during flood season considering spillway optimization
Liu, Xinyuan; Chen, Lu; Zhu, Yonghui; Singh, Vijay P.; Qu, Geng; Guo, Xiaohu
2017-09-01
Flood control and hydropower generation are two main functions of Three Gorges Reservoir (TGR) in China. In this study, a multi-objective operation model for TGR considering these two functions was developed. Since the optimal results of reservoir operation are mostly in the form of gross outflow which is hardly used to directly guide reservoir operation, the optimization of spillways operation was taken into account. For observed historical flood hydrographs and design flood hydrographs, the progressive optimality algorithm (POA) was employed to determine the optimal operation of spillways. For the real-time reservoir operation, a smooth support vector machine (SSVM) model was applied to abstract the optimal operation rules which consider the order and the number of spillways put into use. Results demonstrate that the use of different spillways has a significant impact on reservoir operation. Therefore, it is necessary to consider the order and number of spillways that should be used. Instead of optimizing outflow, direct optimization of the order and number of spillways can yield most reasonable results. The SSVM model simulates the relationship among inflow, water level and outflow satisfactorily and can be used for real-time or short term reservoir operation. Application of the SSVM model can also reduce flood risk and increase hydropower generation during the flood season.
Optimal operation of rapid pressure swing adsorption with slop recycling
Betlem, Bernardus H.L.; Gotink, R.W.M.; Bosch, H.
1998-01-01
Rapid pressure swing adsorption (RPSA) is a cyclic process operating, basically, in three phases: a pressurization, a delay, and a depressurization phase. A new, modified operation is suggested by the addition of either a raffinate recycle phase or an extract recycle phase, during which raffinate re
Supervising UAVs : improving operator performance by optimizing the human factor
Breda, L. van; Jansen, C.; Veltman, J.A.
2005-01-01
Tele-operated unmanned aerial vehicles (UAVs) have no operators on board and therefore enable extension of the present sensing and communication capabilities in civil and military missions, without unnecessarily endangering personnel or deploying expensive material. One should also realize that tele
Supervising UAVs : improving operator performance by optimizing the human factor
Breda, L. van; Jansen, C.; Veltman, J.A.
2005-01-01
Tele-operated unmanned aerial vehicles (UAVs) have no operators on board and therefore enable extension of the present sensing and communication capabilities in civil and military missions, without unnecessarily endangering personnel or deploying expensive material. One should also realize that tele
Institute of Scientific and Technical Information of China (English)
无
2011-01-01
For the first time in the last three years, China’s listed companies reported lower profit growth By October 31, most of the companies listed in China’s A-share market had published their performance for the third quarter. Reports or corporate ann
DEFF Research Database (Denmark)
Ritter, Thomas; Lund Pedersen, Carsten; Eibe Sørensen, Hans
sammen for at udnytte mulighederne for datadreven profitabel vækst. Denne guide giver en anvendelsesorienteret gennemgang af de ni kompetencer i vores kort, som vi kalder for DataProfit. I guiden beskrives hver kompetence – og du inviteres til at analysere din virksomhed. Til sidst sætter vi hele...
Design, Performance and Optimization for Multimodal Radar Operation
Directory of Open Access Journals (Sweden)
Surendra S. Bhat
2012-09-01
Full Text Available This paper describes the underlying methodology behind an adaptive multimodal radar sensor that is capable of progressively optimizing its range resolution depending upon the target scattering features. It consists of a test-bed that enables the generation of linear frequency modulated waveforms of various bandwidths. This paper discusses a theoretical approach to optimizing the bandwidth used by the multimodal radar. It also discusses the various experimental results obtained from measurement. The resolution predicted from theory agrees quite well with that obtained from experiments for different target arrangements.
Driving external chemistry optimization via operations management principles.
Bi, F Christopher; Frost, Heather N; Ling, Xiaolan; Perry, David A; Sakata, Sylvie K; Bailey, Simon; Fobian, Yvette M; Sloan, Leslie; Wood, Anthony
2014-03-01
Confronted with the need to significantly raise the productivity of remotely located chemistry CROs Pfizer embraced a commitment to continuous improvement which leveraged the tools from both Lean Six Sigma and queue management theory to deliver positive measurable outcomes. During 2012 cycle times were reduced by 48% by optimization of the work in progress and conducting a detailed workflow analysis to identify and address pinch points. Compound flow was increased by 29% by optimizing the request process and de-risking the chemistry. Underpinning both achievements was the development of close working relationships and productive communications between Pfizer and CRO chemists.
Optimizing Resources of United States Navy for Humanitarian Operations
2014-08-26
roads are not traversable and bridges have collapsed. There is no potable water available. There is the fear of outbreak of diseases like cholera and...12 Table 10. Results of Sensitivity Analysis, Ships in the Optimal Solutions ...... 13 ^Åèìáëáíáçå=oÉëÉ~êÅÜ=mêçÖê~ã= dê~Çì~íÉ=pÅÜççä=çÑ...discover which ships show up in the optimal solution often. The demands were varied based on the past disaster characteristics and the affected area
Optimal Offering and Operating Strategy for a Large Wind-Storage System as a Price Maker
DEFF Research Database (Denmark)
Ding, Huajie; Pinson, Pierre; Hu, Zechun
2017-01-01
Wind farms and energy storage systems are playing increasingly more important roles in power systems, which makes their offering non-negligible in some markets. From the perspective of wind farm-energy storage systems (WF-ESS), this paper proposes an integrated strategy of day-ahead offering...... and real-time operation policies to maximize their overall profit. As participants with large capacity in electricity markets can influence cleared prices by strategic offering, a large scaled WFESS is assumed to be a price maker in day-ahead markets. Correspondingly, the strategy considers influence...
Optimal operations and resilient investments in steam networks
Directory of Open Access Journals (Sweden)
Stephane Laurent Bungener
2016-01-01
Full Text Available Steam is a key energy vector for industrial sites, most commonly used for process heating and cooling, cogeneration of heat and mechanical power, as a motive fluid or for stripping. Steam networks are used to carry steam from producers to consumers and between pressure levels through letdowns and steam turbines. The steam producers (boilers, heat and power cogeneration units, heat exchangers, chemical reactors should be sized to supply the consumers at nominal operating conditions as well as peak demand.This paper firstly proposes an Mixed Integer Linear Programming formulation to optimise the operations of steam networks in normal operating conditions and exceptional demand (when operating reserves fall to zero, through the introduction of load shedding. Optimisation of investments based on operational and investment costs are included in the formulation.Though rare, boiler failures can have a heavy impact of steam network operations and costs, leading to undercapacity and unit shutdowns. A method is therefore proposed to simulate steam network operations when facing boiler failures. Key performance indicators are introduced to quantify the network's resilience.The proposed methods are applied and demonstrated in an industrial case study using industrial data. The results indicate the importance of oversizing key steam producing equipments and the value of industrial symbiosis to increase industrial site resilience.
2014-05-01
ABSTRACT “The Program for Research on Dietary Supplements in Military Operations and Healthcare: The Metabolically Optimized Brain ( MOB ) Study targets a...Operations and Healthcare: The Metabolically Optimized Brain ( MOB ) Study targets a more specific aspect of dietary nutrition, feeding policy and...psychological consequences of brain injury from high intensity training, and combat operations exposures. The MOB Study has 3 specific aims: 1. Convene a
Product quality driven design of bakery operations using dynamic optimization
Hadiyanto, M.; Esveld, D.C.; Boom, R.M.; Straten, van G.; Boxtel, van A.J.B.
2008-01-01
Abstract Quality driven design uses specified product qualities as a starting point for process design. By backward reasoning the required process conditions and processing system were found. In this work dynamic optimization was used as a tool to generate processing solutions for baking processes b
Chemically Optimizing Operational Efficiency of Molecular Rotary Motors
Conyard, Jamie; Cnossen, Arjen; Browne, Wesley R.; Feringa, Ben L.; Meech, Stephen R.
2014-01-01
Unidirectional molecular rotary motors that harness photoinduced cis-trans (E-Z) isomerization are promising tools for the conversion of light energy to mechanical motion in nanoscale molecular machines. Considerable progress has been made in optimizing the frequency of ground-state rotation, but le
Product quality driven design of bakery operations using dynamic optimization
Hadiyanto, M.; Esveld, D.C.; Boom, R.M.; Straten, van G.; Boxtel, van A.J.B.
2008-01-01
Abstract Quality driven design uses specified product qualities as a starting point for process design. By backward reasoning the required process conditions and processing system were found. In this work dynamic optimization was used as a tool to generate processing solutions for baking processes
Maximum Profit Configurations of Commercial Engines
Yiran Chen
2011-01-01
An investigation of commercial engines with finite capacity low- and high-price economic subsystems and a generalized commodity transfer law [n ∝ Δ (P m)] in commodity flow processes, in which effects of the price elasticities of supply and demand are introduced, is presented in this paper. Optimal cycle configurations of commercial engines for maximum profit are obtained by applying optimal control theory. In some special cases, the eventual state—market equilibrium—is solely determined by t...
THE INFLUENCE OF THE MAIN PARAMETERS OF TRAIN TRAFFIC VOLUME ON TOTAL PROFITS OF RAILWAYS
Directory of Open Access Journals (Sweden)
H. YA. Mozolevich
2015-04-01
Full Text Available Purpose. The paper is aimed to influence analysis of parameters such as the number of trains on the section and the length of freight trains, the total profit of the railway and determination of total profit of Prydniprovsk railway for major parts of the trains handling; the determination of the specific rate of return on 1 kilometer operational length of each individual link in the rail network. Methodology. To achieve this goal the simulation models of the sections of railway polygon and the simulation of cargo trains have been developed. On the basis of obtained results the dependence of the main parameters of train traffic and their impact on the overall profit of the railway was determined. Findings. On the basis of the conducted studies the functions operating costs for each section were developed to determine the optimal routes crossing of trains and choice of rational parameters. The operating costs, revenue, total profit of railways and certain impact parameters of train traffic volume on the economic performance of railway transport were calculated with their help. It is determined that freight trains, length 53-56 of a conventional car is optimal to pass and loading area should be 75-85% of the available crossing capacity. Taking into account given results, the electrification of the sections with diesel traction (due to the significant cost of diesel fuel is the priority development of railway transport at the possible increase in size of the movement. Originality. Authors have improved the technology of determining the total profits of railways on the basis of variables train traffic volumes. For the first time the specific rate of profit on the 1 kilometer operational length of the section depending on the size of the average daily traffic is identified and proposed to use to determine the investment attractiveness of the railways. The simulation models of individual sections of the real train polygon at Prydniprovsk railway were
Thermal Battery Operating Gas Atmosphere Control and Heat Transfer Optimization
2012-09-01
Thermo Fisher Scientific (maximum operating temperature 1100 °C). The SS tube was enclosed in a protective quartz tube to insure proper operation...201S Analytical Balance or a Mettler Toledo AT 20 Microbalance. The BaCrO4 used was certified grade from Fisher Scientific. Global measured leak rates...CHAGNON 107 BEAVER CT COCKEYSVILLE MD 21030 2 ASB ATTN J SWEENEY ATTN S SHOEFFERT BOURGES CEDEX ALLEE SAINTE HELENE 18021
On the Operation Mode and Profit-making Approaches of Euramerican Video Websites%十八大以来党的作风建设机制创新
Institute of Scientific and Technical Information of China (English)
杨小云; 李永杰
2016-01-01
In media convergence era, with strong technology, platforms and user advantage, video websites have been continuously opening up commercial blue sea. Video websites developed earlier and more quickly in Euramerican developed?countries. Some main stream websites have mature operation modes, taking lead in the world and enjoying dominant market shares. The Euramerican main stream websites have their own advantages in value proposition, target users, distribution channels, core competence, and partners. The core competitiveness based on their own advantages determines the operation modes and profit-making approaches of individual video websites. In general, the operation modes of Euramerican video websites are classified into UGC, Hulu, combiation of Internet and TV stations, P2P, and interactive social video service mode and so on. The profit-making approaches can roughly be classified into copyright industry chain development, advertising service, paid service, and video e-commerce and so forth. The experience of Euramerican video websites will offer reference for the development of China’s video websites industry.%党的十八大以来，以习近平同志为总书记的新一届中央领导集体把党风廉政建设作为开展工作的突破口，采取了一系列行动，工作扎实、成效显著。其中一个鲜明特点，就是实现了党的作风建设的机制创新，使党的作风建设进入“新常态”。它包括教育养成、示范引导、制度防范以及监督惩戒机制的创新。
Optimal Energy Management of Multi-Microgrids with Sequentially Coordinated Operations
Directory of Open Access Journals (Sweden)
Nah-Oak Song
2015-08-01
Full Text Available We propose an optimal electric energy management of a cooperative multi-microgrid community with sequentially coordinated operations. The sequentially coordinated operations are suggested to distribute computational burden and yet to make the optimal 24 energy management of multi-microgrids possible. The sequential operations are mathematically modeled to find the optimal operation conditions and illustrated with physical interpretation of how to achieve optimal energy management in the cooperative multi-microgrid community. This global electric energy optimization of the cooperative community is realized by the ancillary internal trading between the microgrids in the cooperative community which reduces the extra cost from unnecessary external trading by adjusting the electric energy production amounts of combined heat and power (CHP generators and amounts of both internal and external electric energy trading of the cooperative community. A simulation study is also conducted to validate the proposed mathematical energy management models.
DEFF Research Database (Denmark)
Connolly, David; Lund, Henrik; Finn, P.
2011-01-01
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......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......-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...
Optimal Economic Operation of Islanded Microgrid by Using a Modified PSO Algorithm
Directory of Open Access Journals (Sweden)
Yiwei Ma
2015-01-01
Full Text Available An optimal economic operation method is presented to attain a joint-optimization of cost reduction and operation strategy for islanded microgrid, which includes renewable energy source, the diesel generator, and battery storage system. The optimization objective is to minimize the overall generating cost involving depreciation cost, operation cost, emission cost, and economic subsidy available for renewable energy source, while satisfying various equality and inequality constraints. A novel dynamic optimization process is proposed based on two different operation control modes where diesel generator or battery storage acts as the master unit to maintain the system frequency and voltage stability, and a modified particle swarm optimization algorithm is applied to get faster solution to the practical economic operation problem of islanded microgrid. With the example system of an actual islanded microgrid in Dongao Island, China, the proposed models, dynamic optimization strategy, and solution algorithm are verified and the influences of different operation strategies and optimization algorithms on the economic operation are discussed. The results achieved demonstrate the effectiveness and feasibility of the proposed method.
Optimizing the Operation of Maceration to Obtain Quality White Wines
Directory of Open Access Journals (Sweden)
Stegărus Diana
2014-06-01
Full Text Available This study monitors the physico-chemical properties of wines from Dragasani under the influence of pectolytic enzymes in various temperature conditions. during maceration contact is made between the grape skins and selected the optimal time leads to wines with more pronounced floral character. The physico-chemical extraction maceration leads to a more pronounced specific compounds, the time of maceration is very important in this case. The curing time is of great importance in producing varieties Muscat Ottonel and Tămâioasă Românească primarily for successful extraction of aromatic components from grape. As noted in the literature flavored grapes contain large amounts of terpene compounds are in free form or bound. To optimize the technological process is able to extract these compounds and to achieve a harmonious and balanced wine. The variants considered in the study presents the results of physico-chemical and aromatic wines obtained from the Muscat Ottonel and Tămâioasă Românească, which took into consideration both during maceration and the use of selected yeasts and enzymes, which form the basis for the selection of the optimal procedure for obtaining aromatic white wines in Dragasani Vineyard.
Support Vector Regression and Genetic Algorithm for HVAC Optimal Operation
Directory of Open Access Journals (Sweden)
Ching-Wei Chen
2016-01-01
Full Text Available This study covers records of various parameters affecting the power consumption of air-conditioning systems. Using the Support Vector Machine (SVM, the chiller power consumption model, secondary chilled water pump power consumption model, air handling unit fan power consumption model, and air handling unit load model were established. In addition, it was found that R2 of the models all reached 0.998, and the training time was far shorter than that of the neural network. Through genetic programming, a combination of operating parameters with the least power consumption of air conditioning operation was searched. Moreover, the air handling unit load in line with the air conditioning cooling load was predicted. The experimental results show that for the combination of operating parameters with the least power consumption in line with the cooling load obtained through genetic algorithm search, the power consumption of the air conditioning systems under said combination of operating parameters was reduced by 22% compared to the fixed operating parameters, thus indicating significant energy efficiency.
Cost optimization for series-parallel execution of a collection of intersecting operation sets
Dolgui, Alexandre; Levin, Genrikh; Rozin, Boris; Kasabutski, Igor
2016-05-01
A collection of intersecting sets of operations is considered. These sets of operations are performed successively. The operations of each set are activated simultaneously. Operation durations can be modified. The cost of each operation decreases with the increase in operation duration. In contrast, the additional expenses for each set of operations are proportional to its time. The problem of selecting the durations of all operations that minimize the total cost under constraint on completion time for the whole collection of operation sets is studied. The mathematical model and method to solve this problem are presented. The proposed method is based on a combination of Lagrangian relaxation and dynamic programming. The results of numerical experiments that illustrate the performance of the proposed method are presented. This approach was used for optimization multi-spindle machines and machining lines, but the problem is common in engineering optimization and thus the techniques developed could be useful for other applications.
Benefits and Costs of For-Profit Public Education
Directory of Open Access Journals (Sweden)
Alex Molnar
2001-04-01
Full Text Available As a policy initiative, for-profit operation of public schools has not lived up to the claims of its proponents. An examination of issues such as teaching methods, academic achievement, autonomy, local control, and the image and influence of for-profit public schools suggests that "for-profits" are unlikely to succeed in the long term in improving the overall quality of public education. They do, however, seem capable of harming public schools.
Directory of Open Access Journals (Sweden)
Ian Bentley
1997-01-01
Full Text Available The article deals with the physical and symbolic effects the built environment has on human activities in a capitalist economy. The built environment is integrated in the capitalist economy on three levels: as the focus of a profit-oriented manufacturing industry, as the setting for all sorts of other enterprises and as the built context of the whole economy. The built environment is understood as a commodity. The capitalist system contains inbuilt tensions which have important design implications: the first tension arises because the system, if left to itself, lacks any overall planning functions, the second tension stems from the ability of the system to generate profit and the third arises from the character of labour, which distinguishes it from other commodities used in the production process. In conclusion methods of designing built environments, which perpetuate social order, are discussed.
CSSC's profit doubled and reduobled
Institute of Scientific and Technical Information of China (English)
无
2007-01-01
@@ In 2006, CSSC continued to turn its economic development mode from extensive to intensive.CSSC's profit in 2006 was almost twice the sum total of CSSC's profits in the past 17 years from 1982 to 1998.
Directory of Open Access Journals (Sweden)
Ziang Li
2017-04-01
Full Text Available In this paper, a reinforcement learning (RL-based Sarsa temporal-difference (TD algorithm is applied to search for a unified bidding and operation strategy for a coal-fired power plant with monoethanolamine (MEA-based post-combustion carbon capture under different carbon dioxide (CO2 allowance market conditions. The objective of the decision maker for the power plant is to maximize the discounted cumulative profit during the power plant lifetime. Two constraints are considered for the objective formulation. Firstly, the tradeoff between the energy-intensive carbon capture and the electricity generation should be made under presumed fixed fuel consumption. Secondly, the CO2 allowances purchased from the CO2 allowance market should be approximately equal to the quantity of CO2 emission from power generation. Three case studies are demonstrated thereafter. In the first case, we show the convergence of the Sarsa TD algorithm and find a deterministic optimal bidding and operation strategy. In the second case, compared with the independently designed operation and bidding strategies discussed in most of the relevant literature, the Sarsa TD-based unified bidding and operation strategy with time-varying flexible market-oriented CO2 capture levels is demonstrated to help the power plant decision maker gain a higher discounted cumulative profit. In the third case, a competitor operating another power plant identical to the preceding plant is considered under the same CO2 allowance market. The competitor also has carbon capture facilities but applies a different strategy to earn profits. The discounted cumulative profits of the two power plants are then compared, thus exhibiting the competitiveness of the power plant that is using the unified bidding and operation strategy explored by the Sarsa TD algorithm.
Energy Technology Data Exchange (ETDEWEB)
Niknam, Taher; Meymand, Hamed Zeinoddini; Nayeripour, Majid [Electrical and Electronic Engineering Department, Shiraz University of Technology, Shiraz (Iran)
2010-08-15
Fuel cell power plants (FCPPs) have been taken into a great deal of consideration in recent years. The continuing growth of the power demand together with environmental constraints is increasing interest to use FCPPs in power system. Since FCPPs are usually connected to distribution network, the effect of FCPPs on distribution network is more than other sections of power system. One of the most important issues in distribution networks is optimal operation management (OOM) which can be affected by FCPPs. This paper proposes a new approach for optimal operation management of distribution networks including FCCPs. In the article, we consider the total electrical energy losses, the total electrical energy cost and the total emission as the objective functions which should be minimized. Whereas the optimal operation in distribution networks has a nonlinear mixed integer optimization problem, the optimal solution could be obtained through an evolutionary method. We use a new evolutionary algorithm based on Fuzzy Adaptive Particle Swarm Optimization (FAPSO) to solve the optimal operation problem and compare this method with Genetic Algorithm (GA), Particle Swarm Optimization (PSO), Differential Evolution (DE), Ant Colony Optimization (ACO) and Tabu Search (TS) over two distribution test feeders. (author)
Yi, Gong; Jilin, Cheng; Lihua, Zhang; Rentian, Zhang
2010-06-01
According to different processes of tides and peak-valley electricity prices, this paper determines the optimal start up time in pumping station's 24 hours operation between the rating state and adjusting blade angle state respectively based on the optimization objective function and optimization model for single-unit pump's 24 hours operation taking JiangDu No.4 Pumping Station for example. In the meantime, this paper proposes the following regularities between optimal start up time of pumping station and the process of tides and peak-valley electricity prices each day within a month: (1) In the rating and adjusting blade angle state, the optimal start up time in pumping station's 24 hours operation which depends on the tide generation at the same day varies with the process of tides. There are mainly two kinds of optimal start up time which include the time at tide generation and 12 hours after it. (2) In the rating state, the optimal start up time on each day in a month exhibits a rule of symmetry from 29 to 28 of next month in the lunar calendar. The time of tide generation usually exists in the period of peak electricity price or the valley one. The higher electricity price corresponds to the higher minimum cost of water pumping at unit, which means that the minimum cost of water pumping at unit depends on the peak-valley electricity price at the time of tide generation on the same day. (3) In the adjusting blade angle state, the minimum cost of water pumping at unit in pumping station's 24 hour operation depends on the process of peak-valley electricity prices. And in the adjusting blade angle state, 4.85%˜5.37% of the minimum cost of water pumping at unit will be saved than that of in the rating state.
Highway Companies Deny Windfall Profits
Institute of Scientific and Technical Information of China (English)
Securities Daily
2011-01-01
@@ There is no denying that the real estate industry sees huge profits, but it is hard to imag-ine that the gross profits of highway companies have reached a very high level, becoming another typical industry of huge profits.The sky-high road toll is attracting more and more public concerns about the seemingly low-profile and stable industry.
Optimized System Design to Ensure Safe and Smooth Operation
Institute of Scientific and Technical Information of China (English)
Li Huilin; Zhao Lei; Ren Hua
2008-01-01
After the replacement with automatic system for the down direction hump of Zhengzhou North Station, some problems occurred in the sub-system of the speed control of the TW-2 hump automatic system and the sub-system of the sorting interlocking, such as poor control accuracy, complicated operation, too long time for mode switch of different performances etc. had made it impossible to meet the physical requirements of the sorting performance of the station, having an adverse effect on the safety and efficiency of the hump. Through intensive analysis on both external and internal causes, some counter measures had been put forward to solve the problems and some validations were carried out on the site. Therefore the aims to ensure safe and reliable operation of the station were reached.
Economic feasibility of reequipment terms based on profitability criterion
National Research Council Canada - National Science Library
D.V. Bezugla
2015-01-01
The aim of the article. The aim of the research is to improve the methodological approaches to a priori determining the initial indices of profitability of technological equipment to solve the dynamic optimization task over...
The profitability and production of a beef herd on transitional ...
African Journals Online (AJOL)
The profitability and production of a beef herd on transitional Cymbopogon- Themeda ... emphasizes the need to optimize, rather than maximize, the rate of reproduction. ... Keywords: Beef cattle, cow herd production, extensive farming, lick ...
Enabling a viable technique for the optimization of LNG carrier cargo operations
Alaba, Onakoya Rasheed; Nwaoha, T. C.; Okwu, M. O.
2016-09-01
In this study, we optimize the loading and discharging operations of the Liquefied Natural Gas (LNG) carrier. First, we identify the required precautions for LNG carrier cargo operations. Next, we prioritize these precautions using the analytic hierarchy process (AHP) and experts' judgments, in order to optimize the operational loading and discharging exercises of the LNG carrier, prevent system failure and human error, and reduce the risk of marine accidents. Thus, the objective of our study is to increase the level of safety during cargo operations.
Enabling a Viable Technique for the Optimization of LNG Carrier Cargo Operations
Institute of Scientific and Technical Information of China (English)
Onakoya Rasheed Alaba; T C Nwaoha; M O Okwu
2016-01-01
In this study, we optimize the loading and discharging operations of the Liquefied Natural Gas (LNG) carrier. First, we identify the required precautions for LNG carrier cargo operations. Next, we prioritize these precautions using the analytic hierarchy process (AHP) and experts’ judgments, in order to optimize the operational loading and discharging exercises of the LNG carrier, prevent system failure and human error, and reduce the risk of marine accidents. Thus, the objective of our study is to increase the level of safety during cargo operations.
An Algorithm for the Optimal Matching Speeds of Passenger and Freight Trains in Mixed Operations
Institute of Scientific and Technical Information of China (English)
无
1999-01-01
This paper models the calculation of the optimal matching speeds of passenger and freight trains with various stage control methods for speed in mixed operations, presents a algorithm for the solution and justifies it with a practical example.
[Optimization of Antibiotic Prophylaxis in Minor Gynecologic Operations].
Selikhova, M S; Vdovin, S V; Mikhailovskaya, M V
2015-01-01
The aim of the study was to estimate the efficacy of various variants of antibiotic prophylaxis of infectious complications in female patients after histeroscopy. 109 patients were examined. The patients were hospitalized for planned historoscopy. 55 of them were treated prophylactically to prevent infectious complications with a broad spectrum antibiotic administered intravenously 30 min prior to the operation. A course antimicrobial therapy during the postoperative period was applied to 54 females. The results of the trial showed that single administration of an antimicrobial provided high level prevention of infectious complications, whereas the use of course antimicrobial therapy during the postoperative period was of no advantage by the efficacy.
Cooperative Optimal Operation of Wind-Storage Facilities
DEFF Research Database (Denmark)
Farashbashi-Astaneh, Seyed-Mostafa; Hu, Weihao; Chen, Zhe
2014-01-01
As the penetration of wind power increases in power systems across the world, wind forecast errors become an emerging problem. Storage units are reliable tools to be used in cooperation with wind farms to mitigate imbalance penalties. Nevertheless they are not still economically viable due to huge...... investment cost. We suggest benefitting the storage unit as a regulation service provider beside its normal operation for mitigating wind power imbalances. This idea comes from the fact that storage units have a fast ramping capability which is necessary to meet close to real-time regulation needs...
Cooperative Optimal Operation of Wind-Storage Facilities
DEFF Research Database (Denmark)
Farashbashi-Astaneh, Seyed-Mostafa; Hu, Weihao; Chen, Zhe
2014-01-01
As the penetration of wind power increases in power systems across the world, wind forecast errors become an emerging problem. Storage units are reliable tools to be used in cooperation with wind farms to mitigate imbalance penalties. Nevertheless they are not still economically viable due to huge...... investment cost. We suggest benefitting the storage unit as a regulation service provider beside its normal operation for mitigating wind power imbalances. This idea comes from the fact that storage units have a fast ramping capability which is necessary to meet close to real-time regulation needs...
Short-Time Decoherence of Solid-State Qubit at Optimal Operation Points
Institute of Scientific and Technical Information of China (English)
无
2005-01-01
We investigate the short-time decoherence of a solid-state qubit under Ohmic noise at optimal operation points. The decoherence is analyzed by maximum norm of the deviation density operator. It is shown that at the temperature T = 3 mK, the loss of the fidelity due to decoherence is much smaller than the DiVincenzo low decoherence criterion, which means that the model may be an optimal candidate of qubit for quantum computation.
A.Thillaivanan,; P. Asokan,; K.N.Srinivasan,; Saravanan, R.
2010-01-01
In this paper the complexity of electrical discharge machining process which is very difficult to determine optimal cutting parameters for improving cutting performance has been reported. Optimization of operating parameters is an important step in machining, particularly for operating unconventional machiningprocedure like EDM. A suitable selection of machining parameters for the electrical discharge machining process relies heavily on the operators’ technologies and experience because of th...
Optimization of the principal eigenvalue of the one-dimensional Schrodinger operator
Directory of Open Access Journals (Sweden)
Ryan I. Fernandes
2008-04-01
Full Text Available In this paper we consider two optimization problems related to the principal eigenvalue of the one dimensional Schrodinger operator. These optimization problems are formulated relative to the rearrangement of a fixed function. We show that both problems have unique solutions, and each of these solutions is a fixed point of an appropriate function.
Application of the gravity search algorithm to multi-reservoir operation optimization
Bozorg-Haddad, Omid; Janbaz, Mahdieh; Loáiciga, Hugo A.
2016-12-01
Complexities in river discharge, variable rainfall regime, and drought severity merit the use of advanced optimization tools in multi-reservoir operation. The gravity search algorithm (GSA) is an evolutionary optimization algorithm based on the law of gravity and mass interactions. This paper explores the GSA's efficacy for solving benchmark functions, single reservoir, and four-reservoir operation optimization problems. The GSA's solutions are compared with those of the well-known genetic algorithm (GA) in three optimization problems. The results show that the GSA's results are closer to the optimal solutions than the GA's results in minimizing the benchmark functions. The average values of the objective function equal 1.218 and 1.746 with the GSA and GA, respectively, in solving the single-reservoir hydropower operation problem. The global solution equals 1.213 for this same problem. The GSA converged to 99.97% of the global solution in its average-performing history, while the GA converged to 97% of the global solution of the four-reservoir problem. Requiring fewer parameters for algorithmic implementation and reaching the optimal solution in fewer number of functional evaluations are additional advantages of the GSA over the GA. The results of the three optimization problems demonstrate a superior performance of the GSA for optimizing general mathematical problems and the operation of reservoir systems.
Amazon: Is Profitability a Possibility?
Directory of Open Access Journals (Sweden)
Brett DENNIS
2014-06-01
Full Text Available In today’s society, companies seem to all be following the same trend; growth in profitability at all cost. Higher profits, for the most part, leads to more investors and more potential financing. Amazon.com appears to be breaking that trend, however. Their strategy seems to be growth, but not in profits. We would like to look into how and why Amazon is growing at such a fast pace, while their profits are staying steady at a very low level. Is profitability a possibility for Amazon? We believe that a marginal increase in price could accomplish just that, with a minimal impact to consumers.
Optimization of the steady operation of Shaanxi to Beijing gas pipeline
Energy Technology Data Exchange (ETDEWEB)
Changchun Wu [China University of Petroleum, Beijing (China); Peng Zhang [Beijing Huayou Gas Company (China); Hongsheng Cui [PetroChina, Beijing (China)
2005-07-01
Shaanxi to Beijing gas pipeline is the first one with intermediate compressor stations in China. With one reciprocating compressor station and three centrifugal compressor stations, the pipeline has an annual capacity of about 36..10{sup 8}m{sup 3}. Increasing gas demand in Beijing and commissioning of the three underground gas storage facilities connected to the pipeline make it to operate near to the capacity for most time of a year, which can be approximately considered as steady state. With the goal to minimize the energy cost of the pipeline, a dynamic programming model was established for its optimal steady operation, in which outlet pressures of each compressor station were defined as state variables and compression ratios as decision variables. The optimal solutions of the model showed that the energy cost could be reduced to different extent by means of optimal operation for the different flow-rates of the pipeline, and that the savings of the energy cost from optimal operation may be over 20% compared to the operation schemes specified by traditional experience in some cases. Furthermore, the guidelines for the optimal operation of gas pipelines were revealed from the analysis of the optimal solutions of the model. (author)
IMPROVEMENTS IN ACCOUNTING OF BREWERIES’ PROFIT
Directory of Open Access Journals (Sweden)
I. Sklyaruk
2013-11-01
Full Text Available The peculiarities of formation of the profit of breweries, taking into account the specifics of the production process and business peculiarities were identified. There were found out the specificity of calculation of the expenses, considering the norms of the technological process, the duration of the operating cycle and the specifics of the production of beer and non-alcoholic products, which determine the methodology of formation of the prime price of the products and the price of its sale. The expediency of using the method for phases (with semi-ready and not semi- ready option method of calculation of the semi-finished products of own production there was proved. The irrelevance of using Account 44 “Undistributed profit (uncovered loss” according to its purpose under the current Plan of accounts is shown. The model of using the profit based on the proposed sub-accounts was built and the example of their use was shown.
Jinxian, Qiu; Jilin, Cheng; Jinyao, Luo; Rentian, Zhang; Lihua, Zhang; Yi, Gong
2010-06-01
The following paper puts forward 45 combination schemes of different-type pumps in different daily-average heads and operation loads in Jiangdu Pumping Station. Based on every scheme, the minimum electricity consumption cost selected as the objective function, this paper gives the results of variable speed optimal operations with dynamic planning methods in both considering time-sharing electricity prices and not, simultaneously, it gives the results of fixed speed conventional operation considering time-sharing electricity prices. Then according to the unit energy consumption cost, the paper gives comparison analysis of the effect of different-type pumps in variable speed optimization operation, the conclusions can offer decision-making bases for optimization research of pumping stations considering time-sharing electricity prices and tide levels of Yangtze River, and offer references for transformation and economical operation of large and medium-size pumping stations.
Novel migration operators of biogeography-based optimization and Markov analysis
DEFF Research Database (Denmark)
Guo, Weian; Wang, Lei; Si, Chenyong
2016-01-01
, a number of benchmark tests are carried out to empirically assess the performance of the proposed migration operators, on both low-dimensional and high-dimensional numerical optimization problems. The comparison results demonstrate that the proposed migration operators are feasible and effective to enhance......Biogeography-based optimization (BBO) is a nature-inspired optimization algorithm and has been developed in both theory and practice. In canonical BBO, migration operator is crucial to affect algorithm’s performance. In migration operator, a good solution has a large probability to be selected...... as an immigrant, while a poor solution has a large probability to be selected as an emigrant. The features in an emigrant will be completely replaced by the features in the corresponding immigrant. Hence, the migration operator in canonical BBO causes a significant deterioration of population diversity...
DEFF Research Database (Denmark)
Lythcke-Jørgensen, Christoffer Ernst; Münster, Marie; Ensinas, Adriano Viana
2016-01-01
This paper presents a novel, simple method for reducing external operating condition datasets to be used in multi-generation system optimization models. The method, called the Characteristic Operating Pattern (CHOP) method, is a visually-based aggregation method that clusters reference data based...... on parameter values rather than time of occurrence, thereby preserving important information on short-term relations between the relevant operating parameters. This is opposed to commonly used methods where data are averaged over chronological periods (months or years), and extreme conditions are hidden...... in the averaged values. The CHOP method is tested in a case study where the operation of a fictive Danish combined heat and power plant is optimized over a historical 5-year period. The optimization model is solved using the full external operating condition dataset, a reduced dataset obtained using the CHOP...
Optimizing the SINR operating point of spatial networks
Jindal, Nihar; Weber, Steven
2007-01-01
This paper addresses the following question, which is of interest in the design and deployment of a multiuser decentralized network. Given a total system bandwidth of W Hz and a fixed data rate constraint of R bps for each transmission, how many frequency slots N of size W/N should the band be partitioned into to maximize the number of simultaneous transmissions in the network? In an interference-limited ad-hoc network, dividing the available spectrum results in two competing effects: on the positive side, it reduces the number of users on each band and therefore decreases the interference level which leads to an increased SINR, while on the negative side the SINR requirement for each transmission is increased because the same information rate must be achieved over a smaller bandwidth. Exploring this tradeoff between bandwidth and SINR and determining the optimum value of N in terms of the system parameters is the focus of the paper. Using stochastic geometry, we analytically derive the optimal SINR threshold...
DEFF Research Database (Denmark)
Grønholdt, Lars; Martensen, Anne
2016-01-01
evidence of the employee-customer-profit chain. As it is possible to estimate the links, we have demonstrated their effect on company profitability. The research findings provide a better understanding of the service-profit chain and may help practitioners in improving company financial performance.......This paper examines the links between employee attitudes, customer loyalty and company profitability. From a conceptual point of view, this employee-customer-profit chain, also known as the service-profit chain, is well founded and generally accepted. But for many companies, it seems difficult...... to demonstrate such links, and several issues must be addressed to uncover the links. To investigate these links empirically, a hotel chain provided data matching employee and customer measures with measures of profitability. We have successfully employed a modeling approach, and the paper reports empirical...
Factors Behind Industrial Profit Growth
Institute of Scientific and Technical Information of China (English)
郑玉歆; 李玉红
2008-01-01
This paper analyzes Chinese enterprise industrial profit distribution and profitability rise between 1998 and 2005. Looking at it from the perspective of drivers of total growth, this paper will provide an in-depth analysis of the origins and industry-level factors involved in this growth. It reaches the conclusion that structural change in profits was the main driving force for profit increases, to which heavy industry contributed greatly. Light and machine building industry profit rates improved due to increases in productivity levels, while energy and raw material industry profits increased due to increases in product prices. In addition, average wages grew slower than GDP, and wages among industries varied widely. In general however, this paper sets out to determine which enterprises gained from increases in industrial profitability, and how this gain came about.
Does outsourcing affect hospital profitability?
Danvers, Kreag; Nikolov, Pavel
2010-01-01
Organizations outsource non-core service functions to achieve cost reductions and strategic benefits, both of which can impact profitability performance. This article examines relations between managerial outsourcing decisions and profitability for a multi-state sample of non-profit hospitals, across 16 states and four regions of the United States. Overall regression results indicate that outsourcing does not necessarily improve hospital profitability. In addition, we identify no profitability impact from outsourcing for urban hospitals, but somewhat positive effects for teaching hospitals. Our regional analysis suggests that hospitals located in the Midwest maintain positive profitability effects with outsourcing, but those located in the South realize negative effects. These findings have implications for cost reduction efforts and the financial viability of non-profit hospitals.
Optimization of Process Parameters of Tool Wear in Turning Operation
Directory of Open Access Journals (Sweden)
Manik Barman
2015-04-01
Full Text Available Tool Wear is of great apprehension in machining industries since itaffects the surface quality, dimensional accuracy and production cost of the materials / components. In the present study twenty seven experiments were conducted as per 3 parameter 3 level full factorial design for turning operation of a mild steel specimen with high speed steel (HSS cutting tool. An experimental investigation on cutting tool wear and a mathematical model for tool wear estimation is reported in this paper where the model was simulated by computer programming and it has been found that this model is capable of estimating the wear rate of cutting tool and it provides an optimum set of process parameters for minimum tool wear.
Optimizing wellfield operation in a variable power price regime
DEFF Research Database (Denmark)
Bauer-Gottwein, Peter; Schneider, Raphael; Davidsen, Claus
markets and power price variability is increasing in many markets because of increased penetration of intermittent renewable power sources. In this context the relevant management objective becomes minimizing the cost of energy used for pumping and distribution of groundwater rather than minimizing energy...... the combined wellfield-storage-demand system over the course of a 2-year planning period based on a time series of observed price on the Danish power market and a deterministic, time-varying hourly water demand. In the SDP setup, hourly pumping rates are the decision variables. Constraints include storage...... policy. Minor savings up to 10% were found in the baseline scenario, while the scenario with constant EFP and unlimited pumping rate resulted in savings up to 40%. Key factors determining potential cost savings obtained by flexible wellfield operation under a variable power price regime are the shape...
Control and operation cost optimization of the HISS cryogenic system
Porter, J.; Bieser, F.; Anderson, D.
1983-08-01
The Heavy Ion Spectrometer System (HISS) relies upon superconducting coils of cryostable design to provide a maximum particle bending field of 3 tesla. A previous paper describes the cryogenic facility including helium refrigeration and gas management. A control strategy which has allowed full time unattended operation, along with significant nitrogen and power cost reductions is discussed. Reduction of liquid nitrogen consumption was accomplished by using the sensible heat available in the cold exhaust gas. Measured nitrogen throughput agrees with calculations for sensible heat utilization of zero to 70%. Calculated consumption saving over this range is 40 liters per hour for conductive losses to the supports only. It is found that the measured throughput differential for the total system is higher.
Control and operation cost optimization of the HISS cryogenic system
Energy Technology Data Exchange (ETDEWEB)
Porter, J.; Bieser, F.; Anderson, D.
1983-08-01
The Heavy Ion Spectrometer System (HISS) relies upon superconducting coils of cryostable design to provide a maximum particle bending field of 3 tesla. A previous paper describes the cryogenic facility including helium refrigeration and gas management. This paper discusses a control strategy which has allowed full time unattended operation, along with significant nitrogen and power cost reductions. Reduction of liquid nitrogen consumption has been accomplished by making use of the sensible heat available in the cold exhaust gas. Measured nitrogen throughput agrees with calculations for sensible heat utilization of zero to 70%. Calculated consumption saving over this range is 40 liters per hour for conductive losses to the supports only. The measured throughput differential for the total system is higher.
Upstream profitability in Vietnam
Energy Technology Data Exchange (ETDEWEB)
Ingeberg, K.
1993-12-01
This report outlines the main characteristics of the petroleum industry in Vietnam. First, it discusses the exploration history and the fiscal regime and concession system for international companies searching for new exploration ventures in the country. Second, it presents an economic analysis of exploration and field development decisions. The analysis is based on a cash flow tax model reflecting the current economic framework. Calculations of upstream profitability are based on typical offshore oil project assumptions. The analysis includes the effects of different levels of exploration risks, tax position and tax agreements. The report also compares fiscal terms in Vietnam and Malaysia and their effect on attractivity. 20 refs., 3 figs., 19 tabs.
Institute of Scientific and Technical Information of China (English)
费威
2012-01-01
To ensure the food safety and provide the references for supervision, marketing and purchase of fresh food, this paper builds the optimization model with the variation of fresh food as the decision variable based on the maximum of the expected profit of the distributor, and analyses that the optimal variation is determined by the best sales period, the minimum and the maximum days with the quality the consumers can accept, the marginal revenue of the quality and the cost parameter for the control quality variation, and then the effect of these factors on the optimal variation. It tests the conclusions by the numerical example, and gives some suggestions for the regulators, the distributors and the consumers respectively.%为保证生鲜食品安全性,对生鲜食品的监管、销售和购买提供参考依据,基于销售商预期利润最大化,以生鲜食品变异度为决策变量建立优化模型,分析得出由最佳销售期、消费者能够接受质量水平对应最小和最大天数、质量水平的边际收益和控制质量变异的成本参数共同决定的最优变异度,以及上述因素对最优变异度的影响,并利用数值算例验证结论,最后分别针对监管部门、销售商和消费者给出了建议。
Lee, Dae Young
The design of a small satellite is challenging since they are constrained by mass, volume, and power. To mitigate these constraint effects, designers adopt deployable configurations on the spacecraft that result in an interesting and difficult optimization problem. The resulting optimization problem is challenging due to the computational complexity caused by the large number of design variables and the model complexity created by the deployables. Adding to these complexities, there is a lack of integration of the design optimization systems into operational optimization, and the utility maximization of spacecraft in orbit. The developed methodology enables satellite Multidisciplinary Design Optimization (MDO) that is extendable to on-orbit operation. Optimization of on-orbit operations is possible with MDO since the model predictive controller developed in this dissertation guarantees the achievement of the on-ground design behavior in orbit. To enable the design optimization of highly constrained and complex-shaped space systems, the spherical coordinate analysis technique, called the "Attitude Sphere", is extended and merged with an additional engineering tools like OpenGL. OpenGL's graphic acceleration facilitates the accurate estimation of the shadow-degraded photovoltaic cell area. This technique is applied to the design optimization of the satellite Electric Power System (EPS) and the design result shows that the amount of photovoltaic power generation can be increased more than 9%. Based on this initial methodology, the goal of this effort is extended from Single Discipline Optimization to Multidisciplinary Optimization, which includes the design and also operation of the EPS, Attitude Determination and Control System (ADCS), and communication system. The geometry optimization satisfies the conditions of the ground development phase; however, the operation optimization may not be as successful as expected in orbit due to disturbances. To address this issue
Optimization on class of operator equations in the probabilistic case setting
Institute of Scientific and Technical Information of China (English)
Gen-sun FANG; Li-xin QIAN
2007-01-01
In this paper, we introduce a problem of the optimization of approximate solutions of operator equations in the probabilistic case setting, and prove a general result which connects the relation between the optimal approximation order of operator equations with the asymptotic order of the probabilistic width. Moreover, using this result, we determine the exact orders on the optimal approximate solutions of multivariate Freldholm integral equations of the second kind with the kernels belonging to the multivariate Sobolev class with the mixed derivative in the probabilistic case setting.
Optimization on class of operator equations in the probabilistic case setting
Institute of Scientific and Technical Information of China (English)
2007-01-01
In this paper, we introduce a problem of the optimization of approximate solutions of operator equations in the probabilistic case setting, and prove a general result which connects the relation between the optimal approximation order of operator equations with the asymptotic order of the probabilistic width. Moreover, using this result, we determine the exact orders on the optimal approximate solutions of multivariate Preldholm integral equations of the second kind with the kernels belonging to the multivariate Sobolev class with the mixed derivative in the probabilistic case setting.
Directory of Open Access Journals (Sweden)
Yin Luo
2012-01-01
Full Text Available Traditional pump scheduling models neglect the operation reliability which directly relates with the unscheduled maintenance cost and the wear cost during the operation. Just for this, based on the assumption that the vibration directly relates with the operation reliability and the degree of wear, it could express the operation reliability as the normalization of the vibration level. The characteristic of the vibration with the operation point was studied, it could be concluded that idealized flow versus vibration plot should be a distinct bathtub shape. There is a narrow sweet spot (80 to 100 percent BEP to obtain low vibration levels in this shape, and the vibration also follows similar law with the square of the rotation speed without resonance phenomena. Then, the operation reliability could be modeled as the function of the capacity and rotation speed of the pump and add this function to the traditional model to form the new. And contrast with the tradition method, the result shown that the new model could fix the result produced by the traditional, make the pump operate in low vibration, then the operation reliability could increase and the maintenance cost could decrease.
Directory of Open Access Journals (Sweden)
Baah Aye Kusi
2015-11-01
Full Text Available In this study we aimed at three objectives. First, identify and rank banks based on a composite score comprising of all five du-pont variables. Second, we identify variables in the five step du-pont set up that are most likely to influence bank ROE during and post profit declining periods. And third, we estimate a model to capture the variables that drive bank ROE during and post profit declining periods. We first establish from our rankings that, foreign banks in Ghana performed better during profit declining periods while the local banks performed better in post profit decline periods using the top ten banks as a benchmark in both periods. Employing Pearson correlation coefficients matrix, we recognized that operating profit margin, asset turnover and leverage were most likely to influence bank ROE in both time periods. We further employ OLS regression and find that bank ROE was impacted by operating profit margin and leverage during profit declining periods and post profit decline while tax effect added up in post profit declining periods.
Optimal edge detection using multiple operators for image understanding
Directory of Open Access Journals (Sweden)
Stathaki Tania
2011-01-01
Full Text Available Abstract Extraction of features, such as edges for the understanding of aerial images, has been an important objective since the early days of remote sensing. This work aims at describing a new framework which allows for the quantitative combination of a preselected set of edge detectors based on the correspondence between their outcomes. This is inspired from the problem that despite the enormous amount of literature on edge detection techniques, there is no single technique that performs well in every possible image context. Two approaches are proposed for this purpose. The first approach is the well-known receiver operating characteristics analysis which is introduced for a sound quality evaluation of the edge maps estimated by combining different edge detectors. In the second approach, the so-called kappa statistics are employed in a novel fashion to amalgamate the above-mentioned selected edge maps to form an improved final edge image. This method is unique in the sense that the balance between the false detections (false positives and false negatives is explicitly determined in advance and incorporated in the proposed method in a mathematical fashion. For the performance evaluation of the proposed techniques, a sample set of the RADIUS/DARPA-IU Fort Hood aerial image database with known ground truth has been used.
Optimal, Risk-based Operation and Maintenance Planning for Offshore Wind Turbines
DEFF Research Database (Denmark)
Sørensen, John Dalsgaard
2008-01-01
For offshore wind turbines costs to operation and maintenance are substantial. This paper describes a risk-based life-cycle approach for optimal planning of operation and maintenance. The approach is based on pre-posterior Bayesian decision theory. Deterioration mechanisms such as fatigue...
Global Optimization of Low-Thrust Interplanetary Trajectories Subject to Operational Constraints
Englander, Jacob A.; Vavrina, Matthew A.; Hinckley, David
2016-01-01
Low-thrust interplanetary space missions are highly complex and there can be many locally optimal solutions. While several techniques exist to search for globally optimal solutions to low-thrust trajectory design problems, they are typically limited to unconstrained trajectories. The operational design community in turn has largely avoided using such techniques and has primarily focused on accurate constrained local optimization combined with grid searches and intuitive design processes at the expense of efficient exploration of the global design space. This work is an attempt to bridge the gap between the global optimization and operational design communities by presenting a mathematical framework for global optimization of low-thrust trajectories subject to complex constraints including the targeting of planetary landing sites, a solar range constraint to simplify the thermal design of the spacecraft, and a real-world multi-thruster electric propulsion system that must switch thrusters on and off as available power changes over the course of a mission.
Fast multi-swarm optimization based-on Cauchy mutation and crossover operation
Institute of Scientific and Technical Information of China (English)
无
2008-01-01
The standard particle swarm optimization (PSO) algorithm is a novel evolutionary algorithm in which each particle studies its own previous best solution and the group's previous best solutions to optimization problems. One problem in PSO is its tendency of trapping into local optima. In this paper, a multi-swarm technique based on fast particle swarm optimization (FPSO) algorithm is proposed by introducing crossover operation. FPSO is global search algorithm which can prevent PSO from trapping into local optima in light of Cauchy mutation. Though it can get high optimizing precision, the convergence rate is not satisfactory. FMSO can not only find satisfying solutions, but also speed up the search.
On the Operation Mode and Profit-making Approaches of Euramerican Video Websites%欧美视频网站运营模式及赢利分析
Institute of Scientific and Technical Information of China (English)
秦宗财; 刘力
2016-01-01
In media convergence era, with strong technology, platforms and user advantage, video websites have been continuously opening up commercial blue sea. Video websites developed earlier and more quickly in Euramerican developed?countries. Some main stream websites have mature operation modes, taking lead in the world and enjoying dominant market shares. The Euramerican main stream websites have their own advantages in value proposition, target users, distribution channels, core competence, and partners. The core competitiveness based on their own advantages determines the operation modes and profit-making approaches of individual video websites. In general, the operation modes of Euramerican video websites are classified into UGC, Hulu, combiation of Internet and TV stations, P2P, and interactive social video service mode and so on. The profit-making approaches can roughly be classified into copyright industry chain development, advertising service, paid service, and video e-commerce and so forth. The experience of Euramerican video websites will offer reference for the development of China’s video websites industry.%融媒时代下视频网站凭借强大的技术、平台和用户优势不断开辟商业蓝海。欧美发达国家视频网站发展较早且较快，一些主流视频网站运营模式较为成熟，在全球处于领先地位并拥有主导性的市场份额。欧美各主流视频网站在价值主张、目标用户、分销渠道、核心能力以及伙伴网络等方面各具优势，基于自身优势而形成的核心竞争力决定了各视频网站的运营模式和赢利途径。总体而言，欧美视频网站运营模式主要分为UGC模式、Hulu模式、网台联动模式、P2P模式和互动社交视频服务模式等；其赢利途径大体分为版权产业链开发、广告服务、付费服务以及视频电商等。欧美视频网站的发展经验可为我国网络视频产业发展提供借鉴。
ENHANCING PROFITABILITY OF A SPINNING
Directory of Open Access Journals (Sweden)
MARSAL Feliu
2014-05-01
Full Text Available Systematic control of the rheological behavior of the ravings in an installation facility dynamometer constant elongation gradient is proposed in this paper. It is an application for all types of spinning both shortfibers as long fibers. Industrial experiments conducted show that this control drawing of the spinning frame is optimized, getting more regular yarns mass with greater industrial profitability. This work is applied to a spinning worsted manufactures fine yarns with high quality requirement The fundamental thesis of our work is that the rheological control of the roving, output from roving frame, either torsional or friction, helps to increase the profitability of the spinning frame and get higher quality yarns. Rheology is the science of movement of the fibers within a fibrous vein, is a sliver or roving from the graph tribocharging-elongation another fundamental concept appears in our analysis: the isocarric elongation. Empirically, we defined this elongation as the difference between the elongation percentage corresponding to half the determined maximum tribocharge on the ascending and descending branches of the tribo-charging elongation curve. The application of these techniques to former machines to roving frame in conventional wool process also allows us to adjust the machines with more speed, reducing the time and product (waste required a change in manufacturing. To increase, for example, the feed of a gill, increase the difficult y for drafting in the following step. These difficulties are directly related to the value of the doubling and drafting that applies: the more doubling and drafting, the greater the difficulty in later steps.
Directory of Open Access Journals (Sweden)
Jian Wang
2014-01-01
Full Text Available A large-scale parallel-unit seawater reverse osmosis desalination plant contains many reverse osmosis (RO units. If the operating conditions change, these RO units will not work at the optimal design points which are computed before the plant is built. The operational optimization problem (OOP of the plant is to find out a scheduling of operation to minimize the total running cost when the change happens. In this paper, the OOP is modelled as a mixed-integer nonlinear programming problem. A two-stage differential evolution algorithm is proposed to solve this OOP. Experimental results show that the proposed method is satisfactory in solution quality.
DEFF Research Database (Denmark)
Anvari-Moghaddam, Amjad; Dragicevic, Tomislav; Meng, Lexuan
2016-01-01
for the proposed plan is derived based on the solution from a mixed-integer nonlinear programming (MINLP) problem. Simulation results showed that including well-sized energy storage options together with optimal operation management of generating units can improve the economic operation of the test system while...... problems to shipboard systems where some means of generation and storage are also schedulable. First, the question of whether or how much energy storage to include into the system is addressed. Both the storage power rating in MW and the capacity in MWh are optimized. Then, optimal operating strategy......Next generation power management at all scales is highly relying on the efficient scheduling and operation of different energy sources to maximize efficiency and utility. The ability to schedule and modulate the energy storage options within energy systems can also lead to more efficient use...
Maximizing profit using recommender systems
Das, Aparna; Ricketts, Daniel
2009-01-01
Traditional recommendation systems make recommendations based solely on the customer's past purchases, product ratings and demographic data without considering the profitability the items being recommended. In this work we study the question of how a vendor can directly incorporate the profitability of items into its recommender so as to maximize its expected profit while still providing accurate recommendations. Our approach uses the output of any traditional recommender system and adjust them according to item profitabilities. Our approach is parameterized so the vendor can control how much the recommendation incorporating profits can deviate from the traditional recommendation. We study our approach under two settings and show that it achieves approximately 22% more profit than traditional recommendations.
Seasonal-Scale Optimization of Conventional Hydropower Operations in the Upper Colorado System
Bier, A.; Villa, D.; Sun, A.; Lowry, T. S.; Barco, J.
2011-12-01
Sandia National Laboratories is developing the Hydropower Seasonal Concurrent Optimization for Power and the Environment (Hydro-SCOPE) tool to examine basin-wide conventional hydropower operations at seasonal time scales. This tool is part of an integrated, multi-laboratory project designed to explore different aspects of optimizing conventional hydropower operations. The Hydro-SCOPE tool couples a one-dimensional reservoir model with a river routing model to simulate hydrology and water quality. An optimization engine wraps around this model framework to solve for long-term operational strategies that best meet the specific objectives of the hydrologic system while honoring operational and environmental constraints. The optimization routines are provided by Sandia's open source DAKOTA (Design Analysis Kit for Optimization and Terascale Applications) software. Hydro-SCOPE allows for multi-objective optimization, which can be used to gain insight into the trade-offs that must be made between objectives. The Hydro-SCOPE tool is being applied to the Upper Colorado Basin hydrologic system. This system contains six reservoirs, each with its own set of objectives (such as maximizing revenue, optimizing environmental indicators, meeting water use needs, or other objectives) and constraints. This leads to a large optimization problem with strong connectedness between objectives. The systems-level approach used by the Hydro-SCOPE tool allows simultaneous analysis of these objectives, as well as understanding of potential trade-offs related to different objectives and operating strategies. The seasonal-scale tool will be tightly integrated with the other components of this project, which examine day-ahead and real-time planning, environmental performance, hydrologic forecasting, and plant efficiency.
1980-07-01
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Energy Technology Data Exchange (ETDEWEB)
Ekelund, Mats [Strateco Develoment AB, Vega (Sweden)], e-mail: mats.e@strateco.se
2012-11-01
Traditionally, the transportation industry has been opposed to any new legislation and when rather stringent emission legislation occurred, they objected just as they did when new fuels came on the agenda. On very short notice, Taxi Stockholm lost 20 % of their business when the County decided to award all public transportation contracts to a competitor. It was time to change plans instead of complaining and to take advantage of new opportunities - 'The first mover advantage'. Making the use of bio fuels into a profitable business takes a change of a standard 'business model' to do and there is still much room others to do the same. With a new CEO, an active marketing department and active individuals among the Board of Directors, Taxi Stockholm massaged a strategy where more business and private customers would be attracted by justifying the green leaf on every cab. All initiatives were publically announced and Taxi Stockholm broke new ice by putting a ban on spike tires - a decision which the vice Mayor made part of her ruling for the whole city. The Ban on gasoline and diesel cars were announced and such a statement attracted business from a loyalty point of view and from companies that had a 'Green Transport Policy' to live up to. Taxi Stockholm has seen growth and profitability grow since and credit the green policy on bio fuels such as bio gas and ethanol for most of it. Preem, Stockholm Transit, Volvo and other market driven operators have all seen markets grow from green initiatives.
Energy Technology Data Exchange (ETDEWEB)
Strohmer, F.
2014-07-01
The profitability of nuclear power plants is worldwide challenged by low electricity prices. One hand low cost shale gas is offering a low price electricity production , other hand additional taxes on fuel are reducing the operating income of nuclear power stations. The optimization of cooling towers can help to increase the efficiency and profit of a nuclear power plant. (Author)
Synthesis Optimization on Galois-Field Based Arithmetic Operators for Rijndael Cipher
Directory of Open Access Journals (Sweden)
Petrus Mursanto
2011-08-01
Full Text Available A series of experiments has been conducted to show that FPGA synthesis of Galois-Field (GF based arithmetic operators can be optimized automatically to improve Rijndael Cipher throughput. Moreover, it has been demonstrated that efficiency improvement in GF operators does not directly correspond to the system performance at application level. The experiments were motivated by so many research works that focused on improving performance of GF operators. Each of the variants has the most efficient form in either time (fastest or space (smallest occupied area when implemented in FPGA chips. In fact, GF operators are not utilized individually, but rather integrated one to the others to implement algorithms. Contribution of this paper is to raise issue on GF-based application performance and suggest alternative aspects that potentially affect it. Instead of focusing on GF operator efficiency, system characteristics are worth considered in optimizing application performance.
PetroChina Sees Gas Pipeline Profit in Four Years
Institute of Scientific and Technical Information of China (English)
Xiao Lu
2002-01-01
@@ Sebei-Xining- Lanzhou pipeline put into operation PetroChina, the nation's largest gas producer,recently said that the US$280-million gas pipeline in Northwest China would generate profits within four years.
Application of PSO algorithm in short-term optimization of reservoir operation.
SaberChenari, Kazem; Abghari, Hirad; Tabari, Hossein
2016-12-01
The optimization of the operation of existing water systems such as dams is very important for water resource planning and management especially in arid and semi-arid lands. Due to budget and operational water resource limitations and environmental problems, the operation optimization is gradually replaced by new systems. The operation optimization of water systems is a complex, nonlinear, multi-constraint, and multidimensional problem that needs robust techniques. In this article, the practical swarm optimization (PSO) was adopted for solving the operation problem of multipurpose Mahabad reservoir dam in the northwest of Iran. The desired result or target function is to minimize the difference between downstream monthly demand and release. The method was applied with considering the reduction probabilities of inflow for the four scenarios of normal and drought conditions. The results showed that in most of the scenarios for normal and drought conditions, released water obtained by the PSO model was equal to downstream demand and also, the reservoir volume was reducing for the probabilities of inflow. The PSO model revealed a good performance to minimize the reservoir water loss, and this operation policy can be an appropriate policy in the drought condition for the reservoir.
Directory of Open Access Journals (Sweden)
KHANBABAZADEH Javad
2016-10-01
Full Text Available Distribution network designers and operators are trying to deliver electrical energy with high reliability and quality to their subscribers. Due to high losses in the distribution systems, using distributed generation can improves reliability, reduces losses and improves voltage profile of distribution network. Therefore, the choice of the location of these resources and also determining the amount of their generated power to maximize the benefits of this type of resource is an important issue which is discussed from different points of view today. In this paper, a new multi-objective optimal location and sizing of distributed generation resources is performed to maximize its benefits on the 33 bus distribution test network considering reliability and using a new Antlion Optimizer (ALO. The benefits for DG are considered as system losses reduction, system reliability improvement and benefits from the sale electricity and voltage profile improvement. For each of the mentioned benefits, the ALO algorithm is used to optimize the location and sizing of distributed generation resources. In order to verify the proposed approach, the obtained results have been analyzed and compared with the results of particle swarm optimization (PSO algorithm. The results show that the ALO has shown better performance in optimization problem solution versus PSO.
A mathematical model for optimized operation and control in a CDQ-Boiler system
Institute of Scientific and Technical Information of China (English)
De Wang; Tao Yang; Zhi Wen; Junxiao Feng; Ning Kong; Qin Wang; Weimin Wang
2005-01-01
Based on analyzing the thermal process of a CDQ (coke dry quenching)-Boiler system, the mathematical model for optimized operation and control in the CDQ-Boiler system was developed. It includes a mathematical model for heat transferring process in the CDQ unit, a mathematical model for heat transferring process in the boiler and a combustion model for circulating gas in the CDQ-Boiler system. The model was verified by field data, then a series of simulations under several typical operating conditions of CDQ-Boiler were carried on, and in tum, the online relation formulas between the productivity and the optimal circulating gas, and the one between the productivity and the optimal second air, were achieved respectively. These relation equations have been successfully used in a CDQ-Boiler computer control system in the Baosteel, to realize online optimized guide and control, and meanwhile high efficiency in the CDQ-Boiler system has been achieved.
DEFF Research Database (Denmark)
Hu, Weihao; Chen, Zhe; Bak-Jensen, Birgitte
2011-01-01
operation strategy for a Plug-In Electric Vehicle (PEV) in relation to the hourly electricity price in order to achieve minimum energy costs of the PEV. The western Danish power system, which is currently the grid area in the world that has the largest share of wind power in its generation profiles and may...... represent the future of electricity markets in some ways, is chosen as the studied power system in this paper. The impact of the optimal operation strategy for electric vehicles together with the optimal load response to spot market price on the distribution power system with high wind power penetrations......Since the hourly spot market price is available one day ahead in Denmark, the electricity price could be transferred to the consumers and they may make some optimal charge and discharge schedules for their electric vehicles in order to minimize their energy costs. This paper presents an optimal...
Collaboration pathway(s) using new tools for optimizing operational climate monitoring from space
Helmuth, Douglas B.; Selva, Daniel; Dwyer, Morgan M.
2014-10-01
Consistently collecting the earth's climate signatures remains a priority for world governments and international scientific organizations. Architecting a solution requires transforming scientific missions into an optimized robust `operational' constellation that addresses the needs of decision makers, scientific investigators and global users for trusted data. The application of new tools offers pathways for global architecture collaboration. Recent (2014) rulebased decision engine modeling runs that targeted optimizing the intended NPOESS architecture, becomes a surrogate for global operational climate monitoring architecture(s). This rule-based systems tools provide valuable insight for Global climate architectures, through the comparison and evaluation of alternatives considered and the exhaustive range of trade space explored. A representative optimization of Global ECV's (essential climate variables) climate monitoring architecture(s) is explored and described in some detail with thoughts on appropriate rule-based valuations. The optimization tools(s) suggest and support global collaboration pathways and hopefully elicit responses from the audience and climate science shareholders.
DEFF Research Database (Denmark)
Hu, Weihao; Chen, Zhe; Bak-Jensen, Birgitte
2011-01-01
Since the hourly spot market price is available one day ahead in Denmark, the electricity price could be transferred to the consumers and they may make some optimal charge and discharge schedules for their electric vehicles in order to minimize their energy costs. This paper presents an optimal...... operation strategy for a Plug-In Electric Vehicle (PEV) in relation to the hourly electricity price in order to achieve minimum energy costs of the PEV. The western Danish power system, which is currently the grid area in the world that has the largest share of wind power in its generation profiles and may...... represent the future of electricity markets in some ways, is chosen as the studied power system in this paper. The impact of the optimal operation strategy for electric vehicles together with the optimal load response to spot market price on the distribution power system with high wind power penetrations...
An Optimal Operating Strategy for Battery Life Cycle Costs in Electric Vehicles
Directory of Open Access Journals (Sweden)
Yinghua Han
2014-01-01
Full Text Available Impact on petroleum based vehicles on the environment, cost, and availability of fuel has led to an increased interest in electric vehicle as a means of transportation. Battery is a major component in an electric vehicle. Economic viability of these vehicles depends on the availability of cost-effective batteries. This paper presents a generalized formulation for determining the optimal operating strategy and cost optimization for battery. Assume that the deterioration of the battery is stochastic. Under the assumptions, the proposed operating strategy for battery is formulated as a nonlinear optimization problem considering reliability and failure number. And an explicit expression of the average cost rate is derived for battery lifetime. Results show that the proposed operating strategy enhances the availability and reliability at a low cost.
Directory of Open Access Journals (Sweden)
S. Woods
2014-01-01
Full Text Available A method of solving optimal manoeuvre control of linear underactuated mechanical systems is presented. The nonintegrable constraints present in such systems are handled by adding dummy actuators and then by applying Lagrange multipliers to reduce their action to zero. The open- and closed-loop control schemes can be analyzed. The method, referred to as the constrained modal space optimal control (CMSOC, is illustrated in the examples of gantry crane operations.
Woods, S; Szyszkowski, W.
2014-01-01
A method of solving optimal manoeuvre control of linear underactuated mechanical systems is presented. The nonintegrable constraints present in such systems are handled by adding dummy actuators and then by applying Lagrange multipliers to reduce their action to zero. The open- and closed-loop control schemes can be analyzed. The method, referred to as the constrained modal space optimal control (CMSOC), is illustrated in the examples of gantry crane operations.
Yu Lu; Xin Chang; An-kang Hu
2016-01-01
The main objective of this article is to describe an innovative methodology for the hydrodynamic optimization of a ship bulbous bow which considers multiple operating conditions. The proposed method is more practical and effective than the traditional optimization process, which is only based on contractually specified design condition. Parametric form approaches are adopted by employing an F-spline curve in order to generate variants of the hull bulbous bow forms using form design parameters...
Optimization of Operational Route in AS/RS Based on Particle Swarm Algorithm
Institute of Scientific and Technical Information of China (English)
无
2008-01-01
Optimization of the operational route in the automated storage/retrieval system (AS/RS) is transformed into the traveling salesman problem. To make the moving distance of the storage/retrieval machine shortest, we carry out a group of tests where 20 goods locations are chosed. Using PSO for operational route of AS/RS, the operation time can be shortened by about 11%. The experiments indicate that under the same conditions, the more the goods locations are, the higher the operation efficiency of the storage/retrieval machine is.
Energy Technology Data Exchange (ETDEWEB)
None
2012-02-24
GENI Project: Sandia National Laboratories is working with several commercial and university partners to develop software for market management systems (MMSs) that enable greater use of renewable energy sources throughout the grid. MMSs are used to securely and optimally determine which energy resources should be used to service energy demand across the country. Contributions of electricity to the grid from renewable energy sources such as wind and solar are intermittent, introducing complications for MMSs, which have trouble accommodating the multiple sources of price and supply uncertainties associated with bringing these new types of energy into the grid. Sandia’s software will bring a new, probability-based formulation to account for these uncertainties. By factoring in various probability scenarios for electricity production from renewable energy sources in real time, Sandia’s formula can reduce the risk of inefficient electricity transmission, save ratepayers money, conserve power, and support the future use of renewable energy.
Chen, Duan; Leon, Arturo S.; Gibson, Nathan L.; Hosseini, Parnian
2016-01-01
Optimizing the operation of a multireservoir system is challenging due to the high dimension of the decision variables that lead to a large and complex search space. A spectral optimization model (SOM), which transforms the decision variables from time domain to frequency domain, is proposed to reduce the dimensionality. The SOM couples a spectral dimensionality-reduction method called Karhunen-Loeve (KL) expansion within the routine of Nondominated Sorting Genetic Algorithm (NSGA-II). The KL expansion is used to represent the decision variables as a series of terms that are deterministic orthogonal functions with undetermined coefficients. The KL expansion can be truncated into fewer significant terms, and consequently, fewer coefficients by a predetermined number. During optimization, operators of the NSGA-II (e.g., crossover) are conducted only on the coefficients of the KL expansion rather than the large number of decision variables, significantly reducing the search space. The SOM is applied to the short-term operation of a 10-reservoir system in the Columbia River of the United States. Two scenarios are considered herein, the first with 140 decision variables and the second with 3360 decision variables. The hypervolume index is used to evaluate the optimization performance in terms of convergence and diversity. The evaluation of optimization performance is conducted for both conventional optimization model (i.e., NSGA-II without KL) and the SOM with different number of KL terms. The results show that the number of decision variables can be greatly reduced in the SOM to achieve a similar or better performance compared to the conventional optimization model. For the scenario with 140 decision variables, the optimal performance of the SOM model is found with six KL terms. For the scenario with 3360 decision variables, the optimal performance of the SOM model is obtained with 11 KL terms.
Optimization of operation of energy supply systems with co-generation and absorption refrigeration
Directory of Open Access Journals (Sweden)
Stojiljković Mirko M.
2012-01-01
Full Text Available Co-generation systems, together with absorption refrigeration and thermal storage, can result in substantial benefits from the economic, energy and environmental point of view. Optimization of operation of such systems is important as a component of the entire optimization process in pre-construction phases, but also for short-term energy production planning and system control. This paper proposes an approach for operational optimization of energy supply systems with small or medium scale co-generation, additional boilers and heat pumps, absorption and compression refrigeration, thermal energy storage and interconnection to the electric utility grid. In this case, the objective is to minimize annual costs related to the plant operation. The optimization problem is defined as mixed integer nonlinear and solved combining modern stochastic techniques: genetic algorithms and simulated annealing with linear programming using the object oriented “ESO-MS” software solution for simulation and optimization of energy supply systems, developed as a part of this research. This approach is applied to optimize a hypothetical plant that might be used to supply a real residential settlement in Niš, Serbia. Results are compared to the ones obtained after transforming the problem to mixed 0-1 linear and applying the branch and bound method.
Optimal operation of batch processes via the tracking of active constraints.
Bonvin, Dominique; Srinivasan, Bala
2003-01-01
This paper presents a new measurement-based optimization framework for batch processes whereby optimal operation can be achieved via the tracking of active constraints. It is shown that, under mild assumptions and to a first-order approximation, tracking the necessary conditions of optimality is equivalent to tracking active constraints (both during the batch and at the end of the batch). Thus the optimal input trajectories can be adjusted using measurements without the use of a model of the process. When only batch-end measurements are available, the proposed method leads itself to an efficient batch-to-batch optimization scheme. The approach is illustrated via the simulation of a semibatch reactor under uncertainty.
Directory of Open Access Journals (Sweden)
Navid Ghadipasha
2016-02-01
Full Text Available This paper discusses the initial steps towards the formulation and implementation of a generic and flexible model centric framework for integrated simulation, estimation, optimization and feedback control of polymerization processes. For the first time it combines the powerful capabilities of the automatic continuous on-line monitoring of polymerization system (ACOMP, with a modern simulation, estimation and optimization software environment towards an integrated scheme for the optimal operation of polymeric processes. An initial validation of the framework was performed for modelling and optimization using literature data, illustrating the flexibility of the method to apply under different systems and conditions. Subsequently, off-line capabilities of the system were fully tested experimentally for model validations, parameter estimation and process optimization using ACOMP data. Experimental results are provided for free radical solution polymerization of methyl methacrylate.
Energy Technology Data Exchange (ETDEWEB)
Pang, X., E-mail: xpang@lanl.gov; Rybarcyk, L.J.
2014-03-21
Particle swarm optimization (PSO) and genetic algorithm (GA) are both nature-inspired population based optimization methods. Compared to GA, whose long history can trace back to 1975, PSO is a relatively new heuristic search method first proposed in 1995. Due to its fast convergence rate in single objective optimization domain, the PSO method has been extended to optimize multi-objective problems. In this paper, we will introduce the PSO method and its multi-objective extension, the MOPSO, apply it along with the MOGA (mainly the NSGA-II) to simulations of the LANSCE linac and operational set point optimizations. Our tests show that both methods can provide very similar Pareto fronts but the MOPSO converges faster.
Pang, X.; Rybarcyk, L. J.
2014-03-01
Particle swarm optimization (PSO) and genetic algorithm (GA) are both nature-inspired population based optimization methods. Compared to GA, whose long history can trace back to 1975, PSO is a relatively new heuristic search method first proposed in 1995. Due to its fast convergence rate in single objective optimization domain, the PSO method has been extended to optimize multi-objective problems. In this paper, we will introduce the PSO method and its multi-objective extension, the MOPSO, apply it along with the MOGA (mainly the NSGA-II) to simulations of the LANSCE linac and operational set point optimizations. Our tests show that both methods can provide very similar Pareto fronts but the MOPSO converges faster.
Optimal Planning and Operation of Hybrid Energy System Supplemented by Storage Devices
DEFF Research Database (Denmark)
Javadi, Mohammad Sadegh; Anvari-Moghaddam, Amjad; Guerrero, Josep M.
2017-01-01
This paper presents a two-stage model for optimal planning and operation of a distribution network. Optimal siting and sizing of renewable energy sources (RES) as well as electrical energy storage (EES) systems are considered in the proposed hybrid energy system. In this context, the planning...... problem is considered as a master problem, while there are different sub-problems associated with the short-term operational problem. To properly handle the uncertainties of forecasted load as well as renewable power generations, fair stochastic models are involved in the sub-problems based on historical...
A MILP-Based Distribution Optimal Power Flow Model for Microgrid Operation
Energy Technology Data Exchange (ETDEWEB)
Liu, Guodong [ORNL; Starke, Michael R [ORNL; Zhang, Xiaohu [ORNL; Tomsovic, Kevin [University of Tennessee, Knoxville (UTK)
2016-01-01
This paper proposes a distribution optimal power flow (D-OPF) model for the operation of microgrids. The proposed model minimizes not only the operating cost, including fuel cost, purchasing cost and demand charge, but also several performance indices, including voltage deviation, network power loss and power factor. It co-optimizes the real and reactive power form distributed generators (DGs) and batteries considering their capacity and power factor limits. The D-OPF is formulated as a mixed-integer linear programming (MILP). Numerical simulation results show the effectiveness of the proposed model.
Dynamic Product Assembly and Inventory Control for Maximum Profit
Neely, Michael J
2010-01-01
We consider a manufacturing plant that purchases raw materials for product assembly and then sells the final products to customers. There are M types of raw materials and K types of products, and each product uses a certain subset of raw materials for assembly. The plant operates in slotted time, and every slot it makes decisions about re-stocking materials and pricing the existing products in reaction to (possibly time-varying) material costs and consumer demands. We develop a dynamic purchasing and pricing policy that yields time average profit within epsilon of optimality, for any given epsilon>0, with a worst case storage buffer requirement that is O(1/epsilon). The policy can be implemented easily for large M, K, yields fast convergence times, and is robust to non-ergodic system dynamics.
A Financial Ratio Analysis of For-Profit and Non-Profit Rural Referral Centers
McCue, Michael J.; Nayar, Preethy
2009-01-01
Context: National financial data show that rural referral center (RRC) hospitals have performed well financially. RRC hospitals' median cash flow margin ratio was 10.04% in 2002 and grew to 11.04% in 2004. Purpose: The aim of this study is to compare the ratio analysis of key operational and financial performance measures of for-profit RRCs to…
Directory of Open Access Journals (Sweden)
Mutlu Yasar
2016-01-01
Full Text Available The Adiguzel Dam is located in Denizli in the western part of Turkey. It was built for irrigation purposes, but it also produces energy at the same time. The dam’s energy-production regime is not regular since there are no reservoir-operating rules. Thus, this study develops a reservoir optimization rule to generate a corresponding gain in energy production. It is well known that operating a reservoir is a complex problem that depends on many parameters such as inflow, storage capacity, water elevation, tailwater elevation, and evaporation. Therefore, in order to optimize energy production, there is a need to use heuristic algorithms such as the Cuckoo Search (CS. This study develops a CS algorithm-based solution to optimize the reservoir’s operational system and generate an optimal operation rule curve. Results show that the CS algorithm improves the system operation, and the energy production will be increased by about 10% to a value of 160000 MWh with a corresponding economic gain of about $12 × 106 in total for 183 months.
Optimization and Operation Scheduling for a Steel Plate yard Based on Greedy Algorithm
Directory of Open Access Journals (Sweden)
Zhiying Zhang
2013-07-01
Full Text Available The inbound and outbound operation of plate yards in shipyards lacks effective scheduling with high operation costs. Based on the analysis of steel-in and steel-out operation process, an optimization model aiming to minimize the operation cost was established. The model was formulated as a multi-level combinatorial optimization model, which is finding proper storage locations during the steel-in stage to minimize the cost during the steel-out stage. Furthermore, greedy algorithm was implemented to solve this problem. Finally, application data obtained from a shipyard was used to validate the model, and the result shows that the proposed algorithm is effective to solve the steel stockyards scheduling problem.
Optimal Solution of the EPED Problem Considering Space Areas of HSABC on the Power System Operation
Directory of Open Access Journals (Sweden)
A.N. Afandi
2015-10-01
Full Text Available Recently, the emission problem and economic dispatch (EPED becomes crucial aspects in the power system operation. These aspects are measured technically using financial payments as the total operating cost based on pollutant productions and fuel consumptions throughout individual costs of generating units based on a committed power output to meet a load demand. This paper introduces the newest artificial intelligent computation, harvest season artificial bee colony (HSABC algorithm, for determining the optimal solution of the EPED based on the operating cost function using IEEE-62 bus system with various operational constraints. Results obtained show that HSABC has short time computations and fast convergences while space areas give different implications on performances. The optimal solution produces various individual power outputs, pollutants, and costs.
Optimisation of profits; Den Gewinn optimieren
Energy Technology Data Exchange (ETDEWEB)
Seltmann, T.
1998-09-01
In spite of the new taxation regulations for photovoltaic energy conversion systems, operators of PV systems can make profits. The contribution presents concrete examples. (orig.) [Deutsch] Durch den Verzicht auf die Kleinunternehmerregelung wird der Betreiber einer PV-Anlage zwar umsatzsteuerpflichtig. Wie dargestellt wird, kann er trotzdem auf Dauer einen Gewinn erwirtschaften. In diesem Beitrag wird anhand konkreter Beispiele erlaeutert, was der Betreiber tun muss, um seinen Anlagenertrag steuerlich korrekt und moeglichst gewinnbringend beim Fiskus anzugeben. (orig.)
Economic profit and performance measurement in banking
Ralph C. Kimball
1998-01-01
Successful bank operation requires managers to weigh complex trade-offs between growth, return, and risk. In recent years banks increasingly have adopted innovative performance metrics based on the concept of economic profit, rather than accounting earnings to assist managers in making such difficult and complex decisions. Banks hope in this way to elicit better decision-making by managers and also too align managerial behavior more closely with the interests of shareholders. This article ana...
Wroblewski, David; Katrompas, Alexander M.; Parikh, Neel J.
2009-09-01
A method and apparatus for optimizing the operation of a power generating plant using artificial intelligence techniques. One or more decisions D are determined for at least one consecutive time increment, where at least one of the decisions D is associated with a discrete variable for the operation of a power plant device in the power generating plant. In an illustrated embodiment, the power plant device is a soot cleaning device associated with a boiler.
Directory of Open Access Journals (Sweden)
V. Volkov
2015-12-01
Full Text Available The results of forming methods of determination and system, as a part of the computer-integrated technology of transport operation, estimation of indecies of the optimal temperature state of the ICE and the vehicle under operation conditions, which is provided with the help of analysis of possible schemes and processes of the complex system of combined heating, using the technology of heat accumulation are described.
PROFITABILITY AND FINANCIAL STABILITY
Directory of Open Access Journals (Sweden)
CĂRUNTU CONSTANTIN
2011-09-01
Full Text Available The business activity allows identifying two categories of flows: flows of results and cash flows. Flows affect the income and expenses, participating in training result, the company's profitability. Financial flows involved in their formation both monetary items (which drive the monetary input or output and thus implies a cash flow, and non-cash items (affecting the result, without leading to a cash flow. Are equally identifiable cash flows that do not involve an immediate effect on the outcome or effect on the result equivalent to that spread on the treasury. Financial equilibrium in a general manner evokes the idea of harmony between different elements of a system, which in finance is harmonization of resources with the needs. Financial equilibrium can be defined by the company's ability to secure payment of its proceeds without interruption to current liabilities incurred in implementing its object of activity or tax laws, so it can avoid the risk of bankruptcy. Maintaining financial stability is the essential condition of survival of the enterprise, financial and balanced assessment must take into account the concrete conditions of the occurrence of default.
Akbulut, Ramazan
2011-01-01
The purpose of this study is to investigate the relationship between working capital management and firm profitability of corporations in manufacture sector which are listed in İstanbul Stock Exchange for the period of 2000-2008. Working capital management is important part in firm financial management decision. The ability of the firm to continuously operate in longer period depends on how they deal with investment in working capital management. The optimal of working capital management coul...
湖南移动互联网产业盈利模式的优化与创新%The Profit Model Optimization and Innovation of Hunan Mobile Internet Industry
Institute of Scientific and Technical Information of China (English)
吴青; 李建新
2014-01-01
全球移动互联网产业的商业模式可概括为增值服务模式、授权许可模式、电子商务模式、广告模式和精确营销模式。通过分析湖南移动互联网现有盈利模式，总结出其优化和创新策略，即：以“付费搜索+增值服务+垂直/场景”模式发展移动搜索，以“内容+增值服务+广告流量”模式推动固网移动化，以“UGC+LBS+垂直细分市场+移动支付+二维码”模式发展O2 O业务。%Business model of global mobile Internet industry can be summarized as value-added service model, licensing model,e-commerce model,advertising model,and accurate marketing model. By analyzing the existing profit model of Hunan Mobile Internet,the optimization and innovation strategies are summarized,namely:develo-ping mobile search based on the model of“Paid Search + VAS + vertical / Scene”,promoting mobilization of fixed network based on the model of“Content + VAS + ad traffic”,and developing O2 O business based on the model of“UGC + LBS + vertical market segmentation+ mobile payment + two-dimensional code”.
Design of optimal operating conditions of simulated moving bed adsorptive separation units
Energy Technology Data Exchange (ETDEWEB)
Storti, G. (Univ. degli Studi di Padova (Italy)); Baciocchi, R.; Mazzotti, M.; Morbidelli, M. (Politecnico di Milano (Italy). Dipt. di Chimica Fisica Applicata)
1995-01-01
The design of the optimal operating conditions for simulated moving bed (SMB) adsorptive separation units is considered. A procedure for the a priori selection of the operating conditions to achieve an assigned separation requirement is developed in the frame of equilibrium theory for the equivalent four section countercurrent unit, using a model where the adsorption equilibria are described through the constant selectivity stoichiometric model, while both mass transfer resistance and axial dispersion are neglected. The space of the operating parameters, i.e. the mass flow rate ratios m[sub j], is divided in regions with different separation regimes. Curves at constant outlets purity and recovery are drawn in the (m[sub 2],m[sub 3]) plane. The introduction of three performance parameters, desorbent requirement, adsorbent requirement, and productivity, allows the development of a procedure for the design of optimal operating conditions. This procedure is completed, accounting for the effect of the switching time on the separation performances, with a detailed model of the SMB unit, considering both axial dispersion and mass transfer resistance. This result constitutes a useful tool for determining the range of operating conditions to achieve an assigned separation requirement and then for selecting the optimal operating condition within this range.
Optimized cascade reservoir operation considering ice flood control and power generation
Chang, Jianxia; Meng, Xuejiao; Wang, ZongZhi; Wang, Xuebin; Huang, Qiang
2014-11-01
Ice flood control is an important objective for reservoir operation in cold regions. Maintaining the reservoir outflow in a certain range is considered an effective way to remediate ice flood damage. However, this strategy may decrease the socio-economic benefit of reservoirs, for example, reduction of hydropower production. These conflicting objectives cause a dilemma for water managers when defining reservoir operation policy. This study considers seven cascade reservoirs in the upstream Yellow River, and ice flood control storage is introduced to balance the hydropower generation and ice flood control. The relation between the ice flood control storage volume of the Liujiaxia reservoir and cascade power output is analyzed. An optimization model to explore the trade-offs between hydropower generation and ice flood control requirements is developed. The model takes into account ice flood control requirements. The optimization model compared to simulation model based on the reservoir operation rule curves. The results show that the optimal operation rules are far more efficient in balancing the benefits within the power generation and ice flood control. The cascade reservoirs operation strategies proposed in this study can be effectively and suitably used in reservoir operation systems with similar conditions.
Optimization of recirculating laminar air flow in operating room air conditioning systems
Directory of Open Access Journals (Sweden)
Enver Yalcin
2016-04-01
Full Text Available The laminar flow air-conditioning system with 100% fresh air is used in almost all operating rooms without discrimination in Turkey. The laminar flow device which is working with 100% fresh air should be absolutely used in Type 1A operating rooms. However, there is not mandatory to use of 100% fresh air for Type 1B defined as places performed simpler operation. Compared with recirculating laminar flow, energy needs of the laminar flow with 100 % fresh air has been emerged about 40% more than re-circulated air flow. Therefore, when a recirculating laminar flow device is operated instead of laminar flow system with 100% fresh air in the Type 1B operating room, annual energy consumption will be reduced. In this study, in an operating room with recirculating laminar flow, optimal conditions have been investigated in order to obtain laminar flow form by analyzing velocity distributions at various supply velocities by using computational fluid dynamics method (CFD.
Bramwell Osula; Eddie C. W. Ng
2014-01-01
In this paper, the authors propose extending the construct of non-profit leadership to accommodate collaborative and transformational themes. The suggestion is that the resultant broader definition accords with the modern context within which non-profits now operate and feeds into a more resilient model of non-profit leadership. The paper begins with a review of emergent trends in leadership theory and the changing context of the non-profit sector. The argument is made that the extraordinary...
Chu, J.; Zhang, C.; Fu, G.; Li, Y.; Zhou, H.
2015-08-01
This study investigates the effectiveness of a sensitivity-informed method for multi-objective operation of reservoir systems, which uses global sensitivity analysis as a screening tool to reduce computational demands. Sobol's method is used to screen insensitive decision variables and guide the formulation of the optimization problems with a significantly reduced number of decision variables. This sensitivity-informed method dramatically reduces the computational demands required for attaining high-quality approximations of optimal trade-off relationships between conflicting design objectives. The search results obtained from the reduced complexity multi-objective reservoir operation problems are then used to pre-condition the full search of the original optimization problem. In two case studies, the Dahuofang reservoir and the inter-basin multi-reservoir system in Liaoning province, China, sensitivity analysis results show that reservoir performance is strongly controlled by a small proportion of decision variables. Sensitivity-informed dimension reduction and pre-conditioning are evaluated in their ability to improve the efficiency and effectiveness of multi-objective evolutionary optimization. Overall, this study illustrates the efficiency and effectiveness of the sensitivity-informed method and the use of global sensitivity analysis to inform dimension reduction of optimization problems when solving complex multi-objective reservoir operation problems.
Optimal Operation System of the Integrated District Heating System with Multiple Regional Branches
Kim, Ui Sik; Park, Tae Chang; Kim, Lae-Hyun; Yeo, Yeong Koo
This paper presents an optimal production and distribution management for structural and operational optimization of the integrated district heating system (DHS) with multiple regional branches. A DHS consists of energy suppliers and consumers, district heating pipelines network and heat storage facilities in the covered region. In the optimal management system, production of heat and electric power, regional heat demand, electric power bidding and sales, transport and storage of heat at each regional DHS are taken into account. The optimal management system is formulated as a mixed integer linear programming (MILP) where the objectives is to minimize the overall cost of the integrated DHS while satisfying the operation constraints of heat units and networks as well as fulfilling heating demands from consumers. Piecewise linear formulation of the production cost function and stairwise formulation of the start-up cost function are used to compute nonlinear cost function approximately. Evaluation of the total overall cost is based on weekly operations at each district heat branches. Numerical simulations show the increase of energy efficiency due to the introduction of the present optimal management system.
Dynamic simulation and optimal real-time operation of CHP systems for buildings
Cho, Hee Jin
Combined Cooling, Heating, and Power (CHP) systems have been widely recognized as a key alternative for electric and thermal energy generation because of their outstanding energy efficiency, reduced environmental emissions, and relative independence from centralized power grids. The systems provide simultaneous onsite or near-site electric and thermal energy generation in a single, integrated package. As CHP becomes increasingly popular worldwide and its total capacity increases rapidly, the research on the topics of CHP performance assessment, design, and operational strategy become increasingly important. Following this trend of research activities to improve energy efficiency, environmental emissions, and operational cost, this dissertation focuses on the following aspects: (a) performance evaluation of a CHP system using a transient simulation model; (b) development of a dynamic simulation model of a power generation unit that can be effectively used in transient simulations of CHP systems; (c) investigation of real-time operation of CHP systems based on optimization with respect to operational cost, primary energy consumption, and carbon dioxide emissions; and (d) development of optimal supervisory feed-forward control that can provide realistic real-time operation of CHP systems with electric and thermal energy storages using short-term weather forecasting. The results from a transient simulation of a CHP system show that technical and economical performance can be readily evaluated using the transient model and that the design, component selection, and control of a CHP system can be improved using this model. The results from the case studies using optimal real-time operation strategies demonstrate that CHP systems with an energy dispatch algorithm have the potential to yield savings in operational cost, primary energy consumption, and carbon dioxide emissions with respect to a conventional HVAC system. Finally, the results from the case study using a
Energetic optimization of a piezo-based touch-operated button for man–machine interfaces
Sun, Hao; Vries, de Theo J.A.; Vries, de Rene; Dalen, van Harry
2012-01-01
This paper discusses the optimization of a touch-operated button for man–machine interfaces based on piezoelectric energy harvesting techniques. In the mechanical button, a common piezoelectric diaphragm, is assembled to harvest the ambient energy from the source, i.e. the operator’s touch. Under to
Energetic optimization of a piezo-based touch-operated button for man–machine interfaces
de Vries, Theodorus J.A.; Sun, H.; de Vries, T.J.A.; de Vries, Rene; van Dalen, Harry
2012-01-01
This paper discusses the optimization of a touch-operated button for man–machine interfaces based on piezoelectric energy harvesting techniques. In the mechanical button, a common piezoelectric diaphragm, is assembled to harvest the ambient energy from the source, i.e. the operator’s touch. Under
Vonk, E.; Xu, YuePing; Booij, Martijn J.; Augustijn, Dionysius C.M.
2016-01-01
In this research we investigate the robustness of the common implicit stochastic optimization (ISO) method for dam reoperation. As a case study, we focus on the Xinanjiang-Fuchunjiang reservoir cascade in eastern China, for which adapted operating rules were proposed as a means to reduce the impact
Yang, Dong; Ren, Wei-Xin; Hu, Yi-Ding; Li, Dan
2015-08-01
The structural health monitoring (SHM) involves the sampled operational vibration measurements over time so that the structural features can be extracted accordingly. The recurrence plot (RP) and corresponding recurrence quantification analysis (RQA) have become a useful tool in various fields due to its efficiency. The threshold selection is one of key issues to make sure that the constructed recurrence plot contains enough recurrence points. Different signals have in nature different threshold values. This paper is aiming at presenting an approach to determine the optimal threshold for the operational vibration measurements of civil engineering structures. The surrogate technique and Taguchi loss function are proposed to generate reliable data and to achieve the optimal discrimination power point where the threshold is optimum. The impact of selecting recurrence thresholds on different signals is discussed. It is demonstrated that the proposed method to identify the optimal threshold is applicable to the operational vibration measurements. The proposed method provides a way to find the optimal threshold for the best RP construction of structural vibration measurements under operational conditions.
Vonk, E.; Xu, Y.P.; Booij, M.J.; Augustijn, D.C.M.
2016-01-01
In this research we investigate the robustness of the common implicit stochastic optimization (ISO) method for dam reoperation. As a case study, we focus on the Xinanjiang-Fuchunjiang reservoir cascade in eastern China, for which adapted operating rules were proposed as a means to reduce the impact
Optimal hysteretic control for a BMAP/SM/1/N queue with two operation modes
Directory of Open Access Journals (Sweden)
Alexander N. Dudin
2000-01-01
Full Text Available We consider BMAP/SM/1 type queueing system with finite buffer of size N. The system has two operation modes, which are characterized by the matrix generating function of BMAP-input, the kernel of the semi-Markovian service process, and utilization cost. An algorithm for determining the optimal hysteresis strategy is presented.
Integrated emission management strategy for cost-optimal engine-aftertreatment operation
Cloudt, R.P.M.; Willems, F.P.T.
2011-01-01
A new cost-based control strategy is presented that optimizes engine-aftertreatment performance under all operating conditions. This Integrated Emission Management strategy minimizes fuel consumption within the set emission limits by on-line adjustment of air management based on the actual state of
Optimization of conventional rule curves coupled with hedging rules for reservoir operation
DEFF Research Database (Denmark)
Taghian, Mehrdad; Rosbjerg, Dan; Haghighi, Ali;
2014-01-01
to achieve the optimal water allocation and the target storage levels for reservoirs. As a case study, a multipurpose, multireservoir system in southern Iran is selected. The results show that the model has good performance in extracting the optimum policy for reservoir operation under both normal...
Naseradinmousavi, Peiman
In this dissertation, the actuator-valve systems as a critical part of the automation system are analyzed. Using physics-based high fidelity modeling, this research provides a set of tools to help understand, predict, optimize, and control the real performance of these complex systems. The work carried out is expected to add to the suite of analytical and numerical tools that are essential for the development of highly automated ship systems. We present an accurate dynamic model, perform nonlinear analysis, and develop optimal design and operation for electromechanical valve systems. The mathematical model derived includes electromagnetics, fluid mechanics, and mechanical dynamics. Nondimensionalization has been carried out in order to reduce the large number of parameters to a few critical independent sets to help carry out a parametric analysis. The system stability analysis is then carried out with the aid of the tools from nonlinear dynamic analysis. This reveals that the system is unstable in a certain region of the parameter space. The system is also shown to exhibit crisis and transient chaotic responses. Smart valves are often operated under local power supply (for various mission-critical reasons) and need to consume as little energy as possible in order to ensure continued operability. The Simulated Annealing (SA) algorithm is utilized to optimize the actuation subsystem yielding the most efficient configuration from the point of view of energy consumption for two sets of design variables. The optimization is particularly important when the smart valves are used in a distributed network. Another aspect of optimality is more subtle and concerns optimal operation given a designed system. Optimal operation comes after the optimal design process to explore if there is any particular method of the valve operation that would yield the minimum possible energy used. The results of our model developed are also validated with the aid of an experimental setup
Institute of Scientific and Technical Information of China (English)
无
2011-01-01
The medium-term runoff forecasting provided new information for forecast of medium and long term runoff and optimal hydroelectric power generation.According to the actual runoff and hydropower generating characteristics of Ertan Hydropower Station,we studied the decade runoff quantitatively and grade forecast model based on Global Forecasting System(GFS) precipitation forecast information in wet season,then used the posteriori runoff transition probability and measurable probability of runoff forecast to research the uncertain runoff description based on runoff forecast;finally on the basis of the runoff description and the grading forecast accuracy of GFS-based next 10 days’total forecast precipitation,we studied the uncertain optimal operating model of Ertan Hydropower Station considering runoff forecast.The results showed that the runoff forecast considering GFS forecast precipitation and uncertainty has significantly improved the existing runoff description and operating optimization model,and obviously raised the hydropower generation efficiency of Ertan Reservoir.
Barbagallo, Simone; Corradi, Luca; de Ville de Goyet, Jean; Iannucci, Marina; Porro, Ivan; Rosso, Nicola; Tanfani, Elena; Testi, Angela
2015-05-17
The Operating Room (OR) is a key resource of all major hospitals, but it also accounts for up 40% of resource costs. Improving cost effectiveness, while maintaining a quality of care, is a universal objective. These goals imply an optimization of planning and a scheduling of the activities involved. This is highly challenging due to the inherent variable and unpredictable nature of surgery. A Business Process Modeling Notation (BPMN 2.0) was used for the representation of the "OR Process" (being defined as the sequence of all of the elementary steps between "patient ready for surgery" to "patient operated upon") as a general pathway ("path"). The path was then both further standardized as much as possible and, at the same time, keeping all of the key-elements that would allow one to address or define the other steps of planning, and the inherent and wide variability in terms of patient specificity. The path was used to schedule OR activity, room-by-room, and day-by-day, feeding the process from a "waiting list database" and using a mathematical optimization model with the objective of ending up in an optimized planning. The OR process was defined with special attention paid to flows, timing and resource involvement. Standardization involved a dynamics operation and defined an expected operating time for each operation. The optimization model has been implemented and tested on real clinical data. The comparison of the results reported with the real data, shows that by using the optimization model, allows for the scheduling of about 30% more patients than in actual practice, as well as to better exploit the OR efficiency, increasing the average operating room utilization rate up to 20%. The optimization of OR activity planning is essential in order to manage the hospital's waiting list. Optimal planning is facilitated by defining the operation as a standard pathway where all variables are taken into account. By allowing a precise scheduling, it feeds the process of
Directory of Open Access Journals (Sweden)
Aida Tayebiyan
2016-06-01
Full Text Available Background: Several reservoir systems have been constructed for hydropower generation around the world. Hydropower offers an economical source of electricity with reduce carbon emissions. Therefore, it is such a clean and renewable source of energy. Reservoirs that generate hydropower are typically operated with the goal of maximizing energy revenue. Yet, reservoir systems are inefficiently operated and manage according to policies determined at the construction time. It is worth noting that with little enhancement in operation of reservoir system, there could be an increase in efficiency of the scheme for many consumers. Methods: This research develops simulation-optimization models that reflect discrete hedging policy (DHP to manage and operate hydropower reservoir system and analyse it in both single and multireservoir system. Accordingly, three operational models (2 single reservoir systems and 1 multi-reservoir system were constructed and optimized by genetic algorithm (GA. Maximizing the total power generation in horizontal time is chosen as an objective function in order to improve the functional efficiency in hydropower production with consideration to operational and physical limitations. The constructed models, which is a cascade hydropower reservoirs system have been tested and evaluated in the Cameron Highland and Batang Padang in Malaysia. Results: According to the given results, usage of DHP for hydropower reservoir system operation could increase the power generation output to nearly 13% in the studied reservoir system compared to present operating policy (TNB operation. This substantial increase in power production will enhance economic development. Moreover, the given results of single and multi-reservoir systems affirmed that hedging policy could manage the single system much better than operation of the multi-reservoir system. Conclusion: It can be summarized that DHP is an efficient and feasible policy, which could be used
Application of the dynamic ant colony algorithm on the optimal operation of cascade reservoirs
Tong, X. X.; Xu, W. S.; Wang, Y. F.; Zhang, Y. W.; Zhang, P. C.
2016-08-01
Due to the lack of dynamic adjustments between global searches and local optimization, it is difficult to maintain high diversity and overcome local optimum problems for Ant Colony Algorithms (ACA). Therefore, this paper proposes an improved ACA, Dynamic Ant Colony Algorithm (DACA). DACA applies dynamic adjustments on heuristic factor changes to balance global searches and local optimization in ACA, which decreases cosines. At the same time, by utilizing the randomness and ergodicity of the chaotic search, DACA implements the chaos disturbance on the path found in each ACA iteration to improve the algorithm's ability to jump out of the local optimum and avoid premature convergence. We conducted a case study with DACA for optimal joint operation of the Dadu River cascade reservoirs. The simulation results were compared with the results of the gradual optimization method and the standard ACA, which demonstrated the advantages of DACA in speed and precision.
Simulation-optimization model of reservoir operation based on target storage curves
Institute of Scientific and Technical Information of China (English)
Hong-bin FANG; Tie-song HU; Xiang ZENG; Feng-yan WU
2014-01-01
This paper proposes a new storage allocation rule based on target storage curves. Joint operating rules are also proposed to solve the operation problems of a multi-reservoir system with joint demands and water transfer-supply projects. The joint operating rules include a water diversion rule to determine the amount of diverted water in a period, a hedging rule based on an aggregated reservoir to determine the total release from the system, and a storage allocation rule to specify the release from each reservoir. A simulation-optimization model was established to optimize the key points of the water diversion curves, the hedging rule curves, and the target storage curves using the improved particle swarm optimization (IPSO) algorithm. The multi-reservoir water supply system located in Liaoning Province, China, including a water transfer-supply project, was employed as a case study to verify the effectiveness of the proposed join operating rules and target storage curves. The results indicate that the proposed operating rules are suitable for the complex system. The storage allocation rule based on target storage curves shows an improved performance with regard to system storage distribution.
Operation Characteristics Optimization of Low Power Three-Phase Asynchronous Motors
Directory of Open Access Journals (Sweden)
VLAD, I.
2014-02-01
Full Text Available Most published papers on low power asynchronous motors were aimed to achieve better operational performances in different operating conditions. The optimal design of the general-purpose motors requires searching and selecting an electric machine to meet minimum operating costs criterion and certain customer imposed restrictive conditions. In this paper, there are many significant simulations providing qualitative and quantitative information on reducing active and reactive energy losses in motors, and on parameters and constructive solution. The optimization study applied the minimal operating costs criterion, and it took into account the starting restrictive conditions. Thirteen variables regarding electromagnetic stresses and main constructive dimensions were considered. The operating costs of the optimized motor decreased with 25.6%, as compared to the existing solution. This paper can be a practical and theoretical support for the development and implementation of modern design methods, based on theoretical and experimental study of stationary and transient processes in low power motors, to increase efficiency and power factor.
Manu, V. S.; Veglia, Gianluigi
2016-12-01
Identity operation in the form of π pulses is widely used in NMR spectroscopy. For an isolated single spin system, a sequence of even number of π pulses performs an identity operation, leaving the spin state essentially unaltered. For multi-spin systems, trains of π pulses with appropriate phases and time delays modulate the spin Hamiltonian to perform operations such as decoupling and recoupling. However, experimental imperfections often jeopardize the outcome, leading to severe losses in sensitivity. Here, we demonstrate that a newly designed Genetic Algorithm (GA) is able to optimize a train of π pulses, resulting in a robust identity operation. As proof-of-concept, we optimized the recoupling sequence in the transferred-echo double-resonance (TEDOR) pulse sequence, a key experiment in biological magic angle spinning (MAS) solid-state NMR for measuring multiple carbon-nitrogen distances. The GA modified TEDOR (GMO-TEDOR) experiment with improved recoupling efficiency results in a net gain of sensitivity up to 28% as tested on a uniformly 13C, 15N labeled microcrystalline ubiquitin sample. The robust identity operation achieved via GA paves the way for the optimization of several other pulse sequences used for both solid- and liquid-state NMR used for decoupling, recoupling, and relaxation experiments.
A prediction of Power Duration Curve from the Optimal Operation of the Multi Reservoirs System
Directory of Open Access Journals (Sweden)
Abdul Wahab Younis
2013-04-01
Full Text Available This study aims of predication Power Duration Curves(PDC resulting from the optimal operation of the multi reservoirs system which comprises the reservoirs of Bakhma dam,Dokan dam and Makhool dam for the division of years over 30 years.Discrete Differential Dynamic Programming(DDDP has been employed to find the optimal operation of the said reservoirs. PDC representing the relationship between the generated hydroelectric power and percentage of operation time equaled or exceeded . The importance of these curves lies in knowing the volume of electric power available for that percentage of operation time. The results have shown that the sum of yearly hydroelectric power for average Release and for the single operation was 5410,1604,2929(Mwfor the reservoirs of Bakhma, Dokan, Makhool dams, which resulted from the application of independent DDDP technology. Also, the hydroelectric power whose generation can be guranteed for 90% of the time is 344.91,107.7,188.15 (Mw for the single operation and 309.1,134.08,140.7 (Mw for the operation as a one system for the reservoirs of Bakhma, Dokan, and Makhool dams respectively.
Optimal Bidding of a Microgrid Based on Probabilistic Analysis of Island Operation
Directory of Open Access Journals (Sweden)
Siyoung Lee
2016-10-01
Full Text Available Island operation of a microgrid increases operation survivability and reliability when there is a large accident in a main grid. However, because a microgrid typically has limited generation capability, a microgrid operator (MGO has to take the risk of island operation into account in its market participation and generation scheduling to ensure efficient operation. In this paper, a microgrid islanding event is interpreted as a trade suspension of a contract, and a set of islanding rules is presented in the form of a market rule. The risk of island operation is evaluated by modeling the microgrid islanding stochastically using an islanding probability function, which is defined in the form of a conditional probability to reflect the influence of outside conditions. An optimal bidding strategy is obtained for the MGO by formulating and solving an optimization problem to minimize the expected operating cost. The effectiveness of the proposed method was investigated by numerical simulations in which the proposed method and two other methods were applied to the same microgrid. Numerical sensitivity analyses of the coefficients of the islanding probability function were conducted to determine how an MGO copes with changes in outside conditions.
Optimization of Operation Sequence in CNC Machine Tools Using Genetic Algorithm
Abu Qudeiri, Jaber; Yamamoto, Hidehiko; Ramli, Rizauddin
The productivity of machine tools is significantly improved by using microcomputer based CAD/CAM systems for NC program generation. Currently, many commercial CAD/CAM packages that provide automatic NC programming have been developed and applied to various cutting processes. Many cutting processes machined by CNC machine tools. In this paper, we attempt to find an efficient solution approach to determine the best sequence of operations for a set of operations that located in asymmetrical locations and different levels. In order to find the best sequence of operations that achieves the shortest cutting tool travel path (CTTP), genetic algorithm is introduced. After the sequence is optimized, the G-codes that use to code for the travel time is created. CTTP can be formulated as a special case of the traveling salesman problem (TSP). The incorporation of genetic algorithm and TSP can be included in the commercial CAD/CAM packages to optimize the CTTP during automatic generation of NC programs.
An Improved Multi-Objective Artificial Bee Colony Optimization Algorithm with Regulation Operators
Directory of Open Access Journals (Sweden)
Jiuyuan Huo
2017-02-01
Full Text Available To achieve effective and accurate optimization for multi-objective optimization problems, a multi-objective artificial bee colony algorithm with regulation operators (RMOABC inspired by the intelligent foraging behavior of honey bees was proposed in this paper. The proposed algorithm utilizes the Pareto dominance theory and takes advantage of adaptive grid and regulation operator mechanisms. The adaptive grid technique is used to adaptively assess the Pareto front maintained in an external archive and the regulation operator is used to balance the weights of the local search and the global search in the evolution of the algorithm. The performance of RMOABC was evaluated in comparison with other nature inspired algorithms includes NSGA-II and MOEA/D. The experiments results demonstrated that the RMOABC approach has better accuracy and minimal execution time.
Developing Virtual Power Plant for Optimized Distributed Energy Resources Operation and Integration
DEFF Research Database (Denmark)
You, Shi
, these sources are usually deployed in way of “fit and forget” which to a great extent confines their value and presents challenges in relation to: Optimized DER operation related to time varying onsite demand requirements, ambient conditions and electricity prices, etc. Coordinated control of many small...... of VPP, the Market-Based VPP (MBVPP) concept is proposed. The function-based MBVPP provides a generic and flexible solution for the DER integration by connecting the DER to the bulk power system operation via market participation. Two schemes for managing the DER generation and trading portfolios, direct...... control and price signal control have been discussed and simulated. Due to their prevalence and controllability, the μCHP systems are modeled to represent the general DER technology in the corresponding studies. For the direct controlled VPP, all the μCHP units are optimally controlled by the VPP operator...
Energy Technology Data Exchange (ETDEWEB)
Flory, John Andrew [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Padilla, Denise D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Gauthier, John H. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Zwerneman, April Marie [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Miller, Steven P [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
2016-05-01
Upcoming weapon programs require an aggressive increase in Application Specific Integrated Circuit (ASIC) production at Sandia National Laboratories (SNL). SNL has developed unique modeling and optimization tools that have been instrumental in improving ASIC production productivity and efficiency, identifying optimal operational and tactical execution plans under resource constraints, and providing confidence in successful mission execution. With ten products and unprecedented levels of demand, a single set of shared resources, highly variable processes, and the need for external supplier task synchronization, scheduling is an integral part of successful manufacturing. The scheduler uses an iterative multi-objective genetic algorithm and a multi-dimensional performance evaluator. Schedule feasibility is assessed using a discrete event simulation (DES) that incorporates operational uncertainty, variability, and resource availability. The tools provide rapid scenario assessments and responses to variances in the operational environment, and have been used to inform major equipment investments and workforce planning decisions in multiple SNL facilities.
Energy and operation management of a microgrid using particle swarm optimization
Radosavljević, Jordan; Jevtić, Miroljub; Klimenta, Dardan
2016-05-01
This article presents an efficient algorithm based on particle swarm optimization (PSO) for energy and operation management (EOM) of a microgrid including different distributed generation units and energy storage devices. The proposed approach employs PSO to minimize the total energy and operating cost of the microgrid via optimal adjustment of the control variables of the EOM, while satisfying various operating constraints. Owing to the stochastic nature of energy produced from renewable sources, i.e. wind turbines and photovoltaic systems, as well as load uncertainties and market prices, a probabilistic approach in the EOM is introduced. The proposed method is examined and tested on a typical grid-connected microgrid including fuel cell, gas-fired microturbine, wind turbine, photovoltaic and energy storage devices. The obtained results prove the efficiency of the proposed approach to solve the EOM of the microgrids.
Business analytics of specialized medical biochemistry laboratory using profit and loss acount
Directory of Open Access Journals (Sweden)
Vikica Buljanović
2011-07-01
Full Text Available Introduction. By measuring the actual effectiveness of a medical biochemistry laboratory’s business operations, we can determine the accounting measure of laboratory’s profitability, where operating expenses of the laboratory are covered by the income generated from the services. A laboratory’s financial report can be based on a profit and loss account, which shows whether or not a business entity, i.e., the laboratory, is making a profit during a particular business period. Methods. Profitability of the Specialized Medical Biochemical Laboratory (Laboratory of the General County Hospital in Našice, Croatia, was determined using the profit and loss account for 2007. Business success was expressed using the accounting measures of marginal contribution, gross income, and operating income, which could show whether or not the laboratory was operating profitably. This procedure allowed us to identify indicators of successful or unsuccessful business operations of the Laboratory. Results. According to the profit and loss account, the operating profit was 719,926 HRK, i.e., the operating margin was 11.7%, indicating that the Laboratory was operating positively. After subtracting all operating expenses per 100 income units, 11.7 units profit remained from the Laboratory’s core business. Conclusion. The Specialized Medical Biochemical Laboratory of the General County Hospital in Našice generated income, i.e., it operated at a profit. The purpose of profit and loss account was to determine the Laboratory operations that had impact on its business effectiveness and could increase the actual profitability. If the laboratory operates at a loss, and no activities are undertaken that would reverse the business toward positive, the analysis may provide information on the cost for the society as a whole of the studied laboratory within the existing healthcare system.
Modeling Reservoir-River Networks in Support of Optimizing Seasonal-Scale Reservoir Operations
Villa, D. L.; Lowry, T. S.; Bier, A.; Barco, J.; Sun, A.
2011-12-01
HydroSCOPE (Hydropower Seasonal Concurrent Optimization of Power and the Environment) is a seasonal time-scale tool for scenario analysis and optimization of reservoir-river networks. Developed in MATLAB, HydroSCOPE is an object-oriented model that simulates basin-scale dynamics with an objective of optimizing reservoir operations to maximize revenue from power generation, reliability in the water supply, environmental performance, and flood control. HydroSCOPE is part of a larger toolset that is being developed through a Department of Energy multi-laboratory project. This project's goal is to provide conventional hydropower decision makers with better information to execute their day-ahead and seasonal operations and planning activities by integrating water balance and operational dynamics across a wide range of spatial and temporal scales. This presentation details the modeling approach and functionality of HydroSCOPE. HydroSCOPE consists of a river-reservoir network model and an optimization routine. The river-reservoir network model simulates the heat and water balance of river-reservoir networks for time-scales up to one year. The optimization routine software, DAKOTA (Design Analysis Kit for Optimization and Terascale Applications - dakota.sandia.gov), is seamlessly linked to the network model and is used to optimize daily volumetric releases from the reservoirs to best meet a set of user-defined constraints, such as maximizing revenue while minimizing environmental violations. The network model uses 1-D approximations for both the reservoirs and river reaches and is able to account for surface and sediment heat exchange as well as ice dynamics for both models. The reservoir model also accounts for inflow, density, and withdrawal zone mixing, and diffusive heat exchange. Routing for the river reaches is accomplished using a modified Muskingum-Cunge approach that automatically calculates the internal timestep and sub-reach lengths to match the conditions of
Wilson, J D
2003-01-01
The technology of Jefferson Laboratory's (JLab) Continuous Electron Beam Accelerator Facility (CEBAF) and Free Electron Laser (FEL) requires cooling from one of the world's largest 2K helium refrigerators known as the Central Helium Liquefier (CHL). The key characteristic of CHL is the ability to maintain a constant low vapor pressure over the large liquid helium inventory using a series of five cold compressors. The cold compressor system operates with a constrained discharge pressure over a range of suction pressures and mass flows to meet the operational requirements of CEBAF and FEL. The research topic is the prediction of the most thermodynamically efficient conditions for the system over its operating range of mass flows and vapor pressures with minimum disruption to JLab operations. The research goal is to find the operating points for each cold compressor for optimizing the overall system at any given flow and vapor pressure.
Energy Technology Data Exchange (ETDEWEB)
Joe D. Wilson, Jr.
2003-04-01
The technology of Jefferson Laboratory's (JLab) Continuous Electron Beam Accelerator Facility (CEBAF) and Free Electron Laser (FEL) requires cooling from one of the world's largest 2K helium refrigerators known as the Central Helium Liquefier (CHL). The key characteristic of CHL is the ability to maintain a constant low vapor pressure over the large liquid helium inventory using a series of five cold compressors. The cold compressor system operates with a constrained discharge pressure over a range of suction pressures and mass flows to meet the operational requirements of CEBAF and FEL. The research topic is the prediction of the most thermodynamically efficient conditions for the system over its operating range of mass flows and vapor pressures with minimum disruption to JLab operations. The research goal is to find the operating points for each cold compressor for optimizing the overall system at any given flow and vapor pressure.
Institute of Scientific and Technical Information of China (English)
Peter Zong
2007-01-01
@@ China has nearly 150 PVC (polyvinyl chloride) manufacturers operated in 2006. Here seventeen publicly listed companies are discussed, representing 25% of the national total output (8.23 million tons).
Enti non profit e diritto dell’Unione Europea
Directory of Open Access Journals (Sweden)
Andrea Perrone
2011-02-01
Full Text Available SOMMARIO: 1. Diritto dell’Unione Europea e disciplina degli enti non profit - 2. Principio di non discriminazione, libera circolazione dei capitali e disposizioni nazionali in materia di fiscalità degli enti non profit - 2.1. Alcune implicazioni sistematiche della recente giurisprudenza della Corte di Giustizia - 2.2. Le ricadute operative e le conseguenze per le confessioni religiose - 3. Agevolazioni fiscali per gli enti non profit come aiuti di Stato? - 3.1. Le conseguenze della giurisprudenza della Corte di Giustizia su una dibattuta questione italiana - 3.2. Uno spunto finale di riflessione.
Chu, J. G.; Zhang, C.; Fu, G. T.; Li, Y.; Zhou, H. C.
2015-04-01
This study investigates the effectiveness of a sensitivity-informed method for multi-objective operation of reservoir systems, which uses global sensitivity analysis as a screening tool to reduce the computational demands. Sobol's method is used to screen insensitive decision variables and guide the formulation of the optimization problems with a significantly reduced number of decision variables. This sensitivity-informed problem decomposition dramatically reduces the computational demands required for attaining high quality approximations of optimal tradeoff relationships between conflicting design objectives. The search results obtained from the reduced complexity multi-objective reservoir operation problems are then used to pre-condition the full search of the original optimization problem. In two case studies, the Dahuofang reservoir and the inter-basin multi-reservoir system in Liaoning province, China, sensitivity analysis results show that reservoir performance is strongly controlled by a small proportion of decision variables. Sensitivity-informed problem decomposition and pre-conditioning are evaluated in their ability to improve the efficiency and effectiveness of multi-objective evolutionary optimization. Overall, this study illustrates the efficiency and effectiveness of the sensitivity-informed method and the use of global sensitivity analysis to inform problem decomposition when solving the complex multi-objective reservoir operation problems.
Zhu, Senlai; Guo, Yuntao; Chen, Jingxu; Li, Dawei; Cheng, Lin
2017-08-02
Most existing network sensor location problem (NSLP) models are designed to identify the number of sensors with fixed costs and installation locations, and sensors are assumed to be installed permanently. However, sometimes sensors are carried by individuals to collect traffic data measurements manually at fixed locations. Hence, their duration of operation for which traffic data measurements are collected is limited, and their costs are not fixed as they are correlated with the duration of operation. This paper proposes a NSLP model that integrates optimal heterogeneous sensor deployment and operation strategies for the dynamic O-D demand estimates under budget constraints. The deployment strategy consists of the numbers of link and node sensors and their installation locations. The operation strategy includes sensors' start time and duration of operation, which has not been addressed in previous studies. An algorithm is developed to solve the proposed model. Numerical experiments performed on a network from a part of Chennai, India show that the proposed model can identify the optimal heterogeneous sensor deployment and operation strategies with the maximum dynamic O-D demand estimation accuracy.
Optimal Design and Operation of Helium Refrigeration Systems Using the Ganni Cycle
Ganni, V.; Knudsen, P.
2010-04-01
The constant pressure ratio process, as implemented in the floating pressure—Ganni cycle, is a new variation to prior cryogenic refrigeration and liquefaction cycle designs that allows for optimal operation and design of helium refrigeration systems. This cycle is based upon the traditional equipment used for helium refrigeration system designs, i.e., constant volume displacement compression and critical flow expansion devices. It takes advantage of the fact that for a given load, the expander sets the compressor discharge pressure and the compressor sets its own suction pressure. This cycle not only provides an essentially constant system Carnot efficiency over a wide load range, but invalidates the traditional philosophy that the (`TS') design condition is the optimal operating condition for a given load using the as-built hardware. As such, the Floating Pressure-Ganni Cycle is a solution to reduce the energy consumption while increasing the reliability, flexibility and stability of these systems over a wide operating range and different operating modes and is applicable to most of the existing plants. This paper explains the basic theory behind this cycle operation and contrasts it to the traditional operational philosophies presently used.
OPTIMAL DESIGN AND OPERATION OF HELIUM REFRIGERATION SYSTEMS USING THE GANNI CYCLE
Energy Technology Data Exchange (ETDEWEB)
Venkatarao Ganni, Peter Knudsen
2010-04-01
The constant pressure ratio process, as implemented in the floating pressure - Ganni cycle, is a new variation to prior cryogenic refrigeration and liquefaction cycle designs that allows for optimal operation and design of helium refrigeration systems. This cycle is based upon the traditional equipment used for helium refrigeration system designs, i.e., constant volume displacement compression and critical flow expansion devices. It takes advantage of the fact that for a given load, the expander sets the compressor discharge pressure and the compressor sets its own suction pressure. This cycle not only provides an essentially constant system Carnot efficiency over a wide load range, but invalidates the traditional philosophy that the (‘TS’) design condition is the optimal operating condition for a given load using the as-built hardware. As such, the Floating Pressure- Ganni Cycle is a solution to reduce the energy consumption while increasing the reliability, flexibility and stability of these systems over a wide operating range and different operating modes and is applicable to most of the existing plants. This paper explains the basic theory behind this cycle operation and contrasts it to the traditional operational philosophies presently used.
Profit Profiles in Correlated Markets
Ingve Simonsen; Kim Sneppen
2001-01-01
We consider a financial market where the asset price follows a fractional Brownian motion. We introduce a family of investment strategies, and quantify profit possibilities for both persistent and antipersistant markets.
Optimal Reservoir Operation for Hydropower Generation using Non-linear Programming Model
Arunkumar, R.; Jothiprakash, V.
2012-05-01
Hydropower generation is one of the vital components of reservoir operation, especially for a large multi-purpose reservoir. Deriving optimal operational rules for such a large multi-purpose reservoir serving various purposes like irrigation, hydropower and flood control are complex, because of the large dimension of the problem and the complexity is more if the hydropower production is not an incidental. Thus optimizing the operations of a reservoir serving various purposes requires a systematic study. In the present study such a large multi-purpose reservoir, namely, Koyna reservoir operations are optimized for maximizing the hydropower production subject to the condition of satisfying the irrigation demands using a non-linear programming model. The hydropower production from the reservoir is analysed for three different dependable inflow conditions, representing wet, normal and dry years. For each dependable inflow conditions, various scenarios have been analyzed based on the constraints on the releases and the results are compared. The annual power production, combined monthly power production from all the powerhouses, end of month storage levels, evaporation losses and surplus are discussed. From different scenarios, it is observed that more hydropower can be generated for various dependable inflow conditions, if the restrictions on releases are slightly relaxed. The study shows that Koyna dam is having potential to generate more hydropower.
Maximum Profit Configurations of Commercial Engines
Directory of Open Access Journals (Sweden)
Yiran Chen
2011-06-01
Full Text Available An investigation of commercial engines with finite capacity low- and high-price economic subsystems and a generalized commodity transfer law [n ∝ Δ (P m] in commodity flow processes, in which effects of the price elasticities of supply and demand are introduced, is presented in this paper. Optimal cycle configurations of commercial engines for maximum profit are obtained by applying optimal control theory. In some special cases, the eventual state—market equilibrium—is solely determined by the initial conditions and the inherent characteristics of two subsystems; while the different ways of transfer affect the model in respects of the specific forms of the paths of prices and the instantaneous commodity flow, i.e., the optimal configuration.
Reducing PAH emissions from the iron ore sintering process by optimizing its operation parameters.
Chen, Yu-Cheng; Tsai, Perng-Jy; Mou, Jin-Luh
2009-06-15
This study set out to reduce polycyclic aromatic hydrocarbon (PAH) emissions from the iron ore sintering process by optimizing its operation parameters obtained from the Taguchi experimental design. Four operating parameters, including the water content (Wc; range = 6.0-7.0 wt %), suction pressure (Ps; range = 1000-1400 mmH2O), bed height (Hb; range = 500-600 mm), and type of hearth layer (HL; including sinter, hematite, and limonite) were selected and conducted on a pilot-scale sinter pot to simulate various sintering operating conditions of a real-scale sinter plant. We found that the resultant optimal combination (Wc = 6.5 wt %, Hb = 600 mm, Ps = 1400 mmH2O, and HL = limonite) could reduce the emission factor of total BaP equivalent concentration (EF(BaPeq)) up to 57.6% in comparison with the current operating condition of a real-scale sinter plant (Wc = 6.5 wt %, Hb = 550 mm, Ps = 1200 mmH2O, and HL = sinter). Through the ANOVA analysis, we found that Ps and Hb were the top two parameters affecting total EF(BaPeq) (accounting, respectively, for 70.9% and 21.2% of the total contribution of the four selected parameters). By examining both the sinter productivity and sinter strength, the values obtained from the optimal combination were quite comparable to those of the current operating condition. The above results further confirm the applicability of the obtained optimal combination for the real-scale sinter plant.
Online Optimization Method for Operation of Generators in a Micro Grid
Hayashi, Yasuhiro; Miyamoto, Hideki; Matsuki, Junya; Iizuka, Toshio; Azuma, Hitoshi
Recently a lot of studies and developments about distributed generator such as photovoltaic generation system, wind turbine generation system and fuel cell have been performed under the background of the global environment issues and deregulation of the electricity market, and the technique of these distributed generators have progressed. Especially, micro grid which consists of several distributed generators, loads and storage battery is expected as one of the new operation system of distributed generator. However, since precipitous load fluctuation occurs in micro grid for the reason of its smaller capacity compared with conventional power system, high-accuracy load forecasting and control scheme to balance of supply and demand are needed. Namely, it is necessary to improve the precision of operation in micro grid by observing load fluctuation and correcting start-stop schedule and output of generators online. But it is not easy to determine the operation schedule of each generator in short time, because the problem to determine start-up, shut-down and output of each generator in micro grid is a mixed integer programming problem. In this paper, the authors propose an online optimization method for the optimal operation schedule of generators in micro grid. The proposed method is based on enumeration method and particle swarm optimization (PSO). In the proposed method, after picking up all unit commitment patterns of each generators satisfied with minimum up time and minimum down time constraint by using enumeration method, optimal schedule and output of generators are determined under the other operational constraints by using PSO. Numerical simulation is carried out for a micro grid model with five generators and photovoltaic generation system in order to examine the validity of the proposed method.
Collaboration pathway(s) using new tools for optimizing `operational' climate monitoring from space
Helmuth, Douglas B.; Selva, Daniel; Dwyer, Morgan M.
2015-09-01
Consistently collecting the earth's climate signatures remains a priority for world governments and international scientific organizations. Architecting a long term solution requires transforming scientific missions into an optimized robust `operational' constellation that addresses the collective needs of policy makers, scientific communities and global academic users for trusted data. The application of new tools offers pathways for global architecture collaboration. Recent rule-based expert system (RBES) optimization modeling of the intended NPOESS architecture becomes a surrogate for global operational climate monitoring architecture(s). These rulebased systems tools provide valuable insight for global climate architectures, by comparison/evaluation of alternatives and the sheer range of trade space explored. Optimization of climate monitoring architecture(s) for a partial list of ECV (essential climate variables) is explored and described in detail with dialogue on appropriate rule-based valuations. These optimization tool(s) suggest global collaboration advantages and elicit responses from the audience and climate science community. This paper will focus on recent research exploring joint requirement implications of the high profile NPOESS architecture and extends the research and tools to optimization for a climate centric case study. This reflects work from SPIE RS Conferences 2013 and 2014, abridged for simplification30, 32. First, the heavily securitized NPOESS architecture; inspired the recent research question - was Complexity (as a cost/risk factor) overlooked when considering the benefits of aggregating different missions into a single platform. Now years later a complete reversal; should agencies considering Disaggregation as the answer. We'll discuss what some academic research suggests. Second, using the GCOS requirements of earth climate observations via ECV (essential climate variables) many collected from space-based sensors; and accepting their
Dar, Zamiyad
The amount of wind energy in power systems is increasing at a significant rate. With this increased penetration, there are certain problems associated with the operation of windfarms which need careful attention. In the operations side, the wake effects of upstream wind turbines on downstream wind turbines can cause a reduction in the total generated power of a windfarm. On the market side, the fluctuation of real-time prices can make the operation of windfarms less profitable. Similarly, the intermittent nature of wind power prevents the windfarms from participating in the day-ahead and forward markets. On the system side, the volatile nature of wind speeds is also an obstacle for windfarms to provide frequency regulation to the system. In this thesis, we address these issues and optimize the operation of windfarms in power systems and deregulated electricity markets. First, the total power generation in a windfarm is maximized by using yaw angle of wind turbines as a control variable. We extend the existing wake models to include the effects of yaw misalignment and wake deflection of wind turbines. A numerical study is performed to find the optimal values of induction factor and yaw misalignment angle of wind turbines in a single row of a windfarm for achieving the maximum total power with wake effects. The numerical study shows that the maximum power is achieved by keeping the induction factor close to 1/3 and only changing the yaw angle to deflect the wake. We then propose a Dynamic Programming Framework (DPF) to maximize the total power production of a windfarm using yaw angle as the control variable. We compare the windfarm efficiency achieved with our DPF with the efficiency values obtained through greedy control strategy and induction factor optimization. We also extend our expressions to a windfarm with multiple rows and columns of turbines and perform simulations on the 3x3 and 4x4 grid topologies. Our results show that the optimal induction factor for
An intelligent factory-wide optimal operation system for continuous production process
Ding, Jinliang; Chai, Tianyou; Wang, Hongfeng; Wang, Junwei; Zheng, Xiuping
2016-03-01
In this study, a novel intelligent factory-wide operation system for a continuous production process is designed to optimise the entire production process, which consists of multiple units; furthermore, this system is developed using process operational data to avoid the complexity of mathematical modelling of the continuous production process. The data-driven approach aims to specify the structure of the optimal operation system; in particular, the operational data of the process are used to formulate each part of the system. In this context, the domain knowledge of process engineers is utilised, and a closed-loop dynamic optimisation strategy, which combines feedback, performance prediction, feed-forward, and dynamic tuning schemes into a framework, is employed. The effectiveness of the proposed system has been verified using industrial experimental results.
Institute of Scientific and Technical Information of China (English)
杨婷
2015-01-01
As a hub of logistics activities, the distribution center plays a role of coordinating organization, schedule control and execution, linking the distribution activities of the whole supply chain. The lean operation control and management of the distribution center can largely reduce the operation cost, and strengthen customer perception of distribution service effect and recognition, so it is the third profit source of logistics enterprises. Based on the theory of value chain, this article optimizes the distribution center operating cost of D express company. The cost optimization model is constructed. The operation cost is reduced through the calculation and optimization of the value chain, and the company's profits are improved.%配送中心作为物流活动的中心枢纽，起着协调组织、调度控制和执行的主要作用，衔接着整条供应链上物配送活动的运行，对配送中心内部进行精益化的作业控制和管理，可以很大程度上降低其作业成本，并有利于增强客户对配送服务的感知效果和认可度，是物流企业的第三利润源泉。本文基于价值链理论对D快递公司配送中心的作业成本进行优化，构建了成本优化模型，通过对价值链的计算与优化，来降低作业的成本消耗，提高公司的利润。
Directory of Open Access Journals (Sweden)
Jamema Swamidas
2009-01-01
Full Text Available Objective : A three dimensional (3D image-based dosimetric study to quantitatively compare geometric vs. dose-point optimization in combination with graphical optimization for interstitial brachytherapy of soft tissue sarcoma (STS. Materials and Methods : Fifteen consecutive STS patients, treated with intra-operative, interstitial Brachytherapy, were enrolled in this dosimetric study. Treatment plans were generated using dose points situated at the "central plane between the catheters", "between the catheters throughout the implanted volume", at "distances perpendicular to the implant axis" and "on the surface of the target volume" Geometrically optimized plans had dose points defined between the catheters, while dose-point optimized plans had dose points defined at a plane perpendicular to the implant axis and on the target surface. Each plan was graphically optimized and compared using dose volume indices. Results : Target coverage was suboptimal with coverage index (CI = 0.67 when dose points were defined at the central plane while it was superior when the dose points were defined at the target surface (CI=0.93. The coverage of graphically optimized plans (GrO was similar to non-GrO with dose points defined on surface or perpendicular to the implant axis. A similar pattern was noticed with conformity index (0.61 vs. 0.82. GrO were more conformal and less homogeneous compared to non-GrO. Sum index was superior for dose points defined on the surface of the target and relatively inferior for plans with dose points at other locations (1.35 vs. 1.27. Conclusions : Optimization with dose points defined away from the implant plane and on target results in superior target coverage with optimal values of other indices. GrO offer better target coverage for implants with non-uniform geometry and target volume.
Optimization of drilling and blasting operations in an open pit mine-the SOMAIR experience
Institute of Scientific and Technical Information of China (English)
AFENI Thomas Busuyi
2009-01-01
Drilling and blasting play vital roles in opencast mining. These operations not only affect the cost of production directly but as well and significantly, the overall operational costs. This research was carried out to find a possible way of optimizing the drilling and blasting operations in an open pit mine of Somair (Societe des Mines de l'Air), in the Niger Republic. In order to opti-mize the drilling operation, the time taken by two drilling machines to accomplish the same task was analyzed statistically. The result indicates that the Down the Hole Hammer Drilling Rig (DMNo406) is more efficient than the Drill Master (DM405). The relative unit consumption of two explosives (Explus and Nitram 9), when used under the same operating conditions, were also con-sidered and the results indicate Explus to be more economical per unit consumption with a range of 0.15 g/t0.183 g/t, when com-pared with Nitram 9 with a unit consumption range of 0.19 g/t-0.24 g/t in the study area.
Electromagnetic Problems Solving by Conformal Mapping: A Mathematical Operator for Optimization
Directory of Open Access Journals (Sweden)
Wesley Pacheco Calixto
2010-01-01
Full Text Available Having the property to modify only the geometry of a polygonal structure, preserving its physical magnitudes, the Conformal Mapping is an exceptional tool to solve electromagnetism problems with known boundary conditions. This work aims to introduce a new developed mathematical operator, based on polynomial extrapolation. This operator has the capacity to accelerate an optimization method applied in conformal mappings, to determinate the equipotential lines, the field lines, the capacitance, and the permeance of some polygonal geometry electrical devices with an inner dielectric of permittivity ε. The results obtained in this work are compared with other simulations performed by the software of finite elements method, Flux 2D.
Institute of Scientific and Technical Information of China (English)
Liu Quan; Hu Zhigen; Fan Wuyi; Ni Jinchu; Li Qinjun
2012-01-01
There is a discharge control feature of construction diversion system with the upstream operational reservoir. The risk evaluation model of construction diversion is established by taking into consideration the risk factors of construc- tion diversion system with discharge control feature as well as their composition. And the risk factors include the up- stream operational reservoir discharge control, the interval flood and branch flood and the diversion system itself. And then based on analyzing of the conversion relation between risk index and investment index of diversion scheme, the risk control and conversion principals of diversion system are put forward, and the feasible diversion scheme model is built. At last, the risk and economic evaluation and scheme economic feasibility analysis method of diversion scheme are shown by an example of construction diversion scheme optimization with the discharge control condition of upstream hydropower station. The study is valuable for establishment and optimization of construction diversion scheme with upstream reservoir discharge control.
Liu, Jianguo; Yang, Bo; Chen, Changzhen
2013-02-01
The optimization of operating parameters for the isolation of peroxidase from horseradish (Armoracia rusticana) roots with ultrafiltration (UF) technology was systemically studied. The effects of UF operating conditions on the transmission of proteins were quantified using the parameter scanning UF. These conditions included solution pH, ionic strength, stirring speed and permeate flux. Under optimized conditions, the purity of horseradish peroxidase (HRP) obtained was greater than 84 % after a two-stage UF process and the recovery of HRP from the feedstock was close to 90 %. The resulting peroxidase product was then analysed by isoelectric focusing, SDS-PAGE and circular dichroism, to confirm its isoelectric point, molecular weight and molecular secondary structure. The effects of calcium ion on HRP specific activities were also experimentally determined.
Punov, Plamen; Milkov, Nikolay; Danel, Quentin; Perilhon, Christelle; Podevin, Pierre; Evtimov, Teodossi
2017-02-01
An optimization study of the Rankine cycle as a function of diesel engine operating mode is presented. The Rankine cycle here, is studied as a waste heat recovery system which uses the engine exhaust gases as heat source. The engine exhaust gases parameters (temperature, mass flow and composition) were defined by means of numerical simulation in advanced simulation software AVL Boost. Previously, the engine simulation model was validated and the Vibe function parameters were defined as a function of engine load. The Rankine cycle output power and efficiency was numerically estimated by means of a simulation code in Python(x,y). This code includes discretized heat exchanger model and simplified model of the pump and the expander based on their isentropic efficiency. The Rankine cycle simulation revealed the optimum value of working fluid mass flow and evaporation pressure according to the heat source. Thus, the optimal Rankine cycle performance was obtained over the engine operating map.
Directory of Open Access Journals (Sweden)
J. Jasper
2014-01-01
Full Text Available This paper addresses a novel and efficient algorithm for solving optimization problem in image processing applications. Image enhancement (IE is one of the complex optimization problems in image processing. The main goal of this paper is to enhance color images such that the eminence of the image is more suitable than the original image from the perceptual viewpoint of human. Traditional methods require prior knowledge of the image to be enhanced, whereas the aim of the proposed biogeography based optimization (BBO enhanced with blended migration operator (BMO algorithm is to maximize the objective function in order to enhance the image contrast by maximizing the parameters like edge intensity, edge information, and entropy. Experimental results are compared with the current state-of-the-art approaches and indicate the superiority of the proposed technique in terms of subjective and objective evaluation.
Optimal operation of cascaded hydroelectric power plants in the power market
Institute of Scientific and Technical Information of China (English)
蔡兴国; 马平; 林士颖
2004-01-01
An improved network flow algorithm, which includes the minimum cost network flow and the same period network flow, is proposed to solve the optimization of cascaded hydroelectric power plants in a competitive electricity market. The typical network flow is used to find the feasible flow and add the discharge water to different cascaded hydroelectric power plants at the same step. The same period network flow is used to find the optimal flow and add the power output at a different step. This new algorithm retains the advantages of the typical network flow, such as simplicity and ease of realization. The result of the case analysis indicates that the new algorithm can achieve high calculation precision and can be used to calculate the optimal operation of cascaded hydroelectric power plants.
DEFF Research Database (Denmark)
Li, Jinghua; Fang, Jiakun; Zeng, Qing
2016-01-01
The integration of electrical and heating systems has great potential to enhance the flexibility of power systems to accommodate more renewable power such as the wind and solar. This study was to investigate an optimal way to integrate the energy of both systems in urban areas. The amount of energy...... conversion between the electrical system and heating system was optimally decided so that the demand within both systems could be met at the least operational cost. Besides, the best node to join with the electrical system and heating system was chosen by consideration of the energy transmission loss....... The mathematic formulation of the optimization problem was detailed as a large-scale non-linear program (LSNLP) in this paper. A decomposition-coordination algorithm was proposed to solve this LSNLP. At last, a 6-bus electrical power system with 31-node heating transmission system was studied to demonstrate...
Profitability of Serbian banking sector during global economic crisis
Directory of Open Access Journals (Sweden)
Marko M Miljković
2013-12-01
Full Text Available The aim of the paper is to identify the main factors which contributed to decline of profitability in Serbian banking sector during the period of global economic crisis. There are presented different theories of banking sector profitability and results of scientifically significant empirical researches from economic literature. Following ratios were used as measure of profitability: return on assets (ROA, return on equity (ROE, net interest gain to total revenue, net fees and commissions gain to total revenue, and net pre-tax profit/loss to total revenue ratio. The profitability was analyzed for the whole Serbian banking sector in the period 2008-2012 and particularly for the 15 largest banks according to total assets value in 2012. The empirical analysis indicated that one of the most important factors contributing to high amounts of losses of commercial banks in the previous period includes an increase of net operating expenses, especially expenses on account of a write-off of non-performing loans (NPL. Furthermore, there were analyzed the dynamics of interest rates and interest spread as a factor with certain impact on profitability of banks. Finally, it is estimated that the prospects for intensive growth of profitability in the banking sector of Serbia in the mid-term are poor.
Feedback Control Method Using Haar Wavelet Operational Matrices for Solving Optimal Control Problems
Waleeda Swaidan; Amran Hussin
2013-01-01
Most of the direct methods solve optimal control problems with nonlinear programming solver. In this paper we propose a novel feedback control method for solving for solving affine control system, with quadratic cost functional, which makes use of only linear systems. This method is a numerical technique, which is based on the combination of Haar wavelet collocation method and successive Generalized Hamilton-Jacobi-Bellman equation. We formulate some new Haar wavelet oper...
A simple quasi-dynamic model of a district heating system used for operational optimization
Energy Technology Data Exchange (ETDEWEB)
Boehm, Benny
1998-12-01
Equivalent models of DH (District Heating) systems are being developed and verified. The models will be used for operational optimization of DH systems. By nature this requires transient models of the DH network, however, some insight can be gained even from a steady state model of the DH network demonstrating the importance of the many parameters which are needed in the models. The temperature level as well as the line heat demand is low in Danish DH systems compared to many foreign DH systems. It has been advocated that the supply temperature should always be kept as low as possible in order to minimize the operational costs. However, this is not true in all cases as the optimum operational strategy will minimize the sum of the heat loss cost and the pumping cost. Thus in case of high line heat demands the supply temperature should not always be kept as low as possible. It has been shown that a simple model, i.e. one pipe - one bypass - one house, can be used for operational optimization, both in the steady state and in the transient case. What remains to be shown is how well this simple model can represent a whole district heating system. The optimization was carried out with matlab routines and with the high number of simulations performed, the computing time is rather long. Even, though much work has already been done, it is still not perfectly clear which demands must be put on simulation and optimization time steps in order to achieve a reliable solution without too much computational effort. (LN)
Optimal Operation and Stabilising Control of the Concentric Heat-Integrated Distillation Column
DEFF Research Database (Denmark)
Bisgaard, Thomas; Skogestad, Sigurd; Huusom, Jakob Kjøbsted
2016-01-01
A systematic control structure design method is applied on the concentric heat integrated distillation column (HIDiC) separating benzene and toluene. A degrees of freedom analysis is provided for identifying potential manipulated and controlled variables. Optimal operation is mapped and active...... structure is finally evaluated by dynamic simulation for proving an acceptable performance. (C) 2016, IFAC (International Federation of Automatic Control) Hosting by Elsevier Ltd. All rights...
Optimization of basic parameters of cyclic operation of underground gas storages
Directory of Open Access Journals (Sweden)
Віктор Олександрович Заєць
2015-04-01
Full Text Available The problem of optimization of process parameters of cyclic operation of underground gas storages in gas mode is determined in the article. The target function is defined, expressing necessary capacity of compressor station for gas injection in the storage. Its minimization will find the necessary technological parameters, such as flow and reservoir pressure change over time. Limitations and target function are reduced to a linear form. Solution of problems is made by the simplex method
Borlawsky, Tara; LaFountain, Jeanne; Petty, Lynda; Saltz, Joel H; Payne, Philip R O
2008-11-06
Workflow analysis is frequently performed in the context of operations research and process optimization. In order to develop a data-driven workflow model that can be employed to assess opportunities to improve the efficiency of perioperative care teams at The Ohio State University Medical Center (OSUMC), we have developed a method for integrating standard workflow modeling formalisms, such as UML activity diagrams with data-centric annotations derived from our existing data warehouse.
1995-05-01
A HYBRID ANALYTICAL/ SIMULATION MODELING APPROACH FOR PLANNING AND OPTIMIZING MASS TACTICAL AIRBORNE OPERATIONS by DAVID DOUGLAS BRIGGS M.S.B.A...COVERED MAY 1995 TECHNICAL REPORT THESIS 4. TITLE AND SUBTITLE 5. FUNDING NUMBERS A HYBRID ANALYTICAL SIMULATION MODELING APPROACH FOR PLANNING AND...are present. Thus, simulation modeling presents itself as an excellent alternate tool for planning because it allows for the modeling of highly complex
Stochastic Optimization Model to STudy the Operational Impacts of High Wind Penetrations in Ireland
DEFF Research Database (Denmark)
Meibom, Peter; Barth, R.; Hasche, B.
2011-01-01
A stochastic mixed integer linear optimization scheduling model minimizing system operation costs and treating load and wind power production as stochastic inputs is presented. The schedules are updated in a rolling manner as more up-to-date information becomes available. This is a fundamental...... of future high wind penetrations for the island of Ireland. Results show that at least 6000 MW of wind (34% of energy demand) can be integrated into the island of Ireland without significant curtailment and reliability problems....
PLIO: a generic tool for real-time operational predictive optimal control of water networks.
Cembrano, G; Quevedo, J; Puig, V; Pérez, R; Figueras, J; Verdejo, J M; Escaler, I; Ramón, G; Barnet, G; Rodríguez, P; Casas, M
2011-01-01
This paper presents a generic tool, named PLIO, that allows to implement the real-time operational control of water networks. Control strategies are generated using predictive optimal control techniques. This tool allows the flow management in a large water supply and distribution system including reservoirs, open-flow channels for water transport, water treatment plants, pressurized water pipe networks, tanks, flow/pressure control elements and a telemetry/telecontrol system. Predictive optimal control is used to generate flow control strategies from the sources to the consumer areas to meet future demands with appropriate pressure levels, optimizing operational goals such as network safety volumes and flow control stability. PLIO allows to build the network model graphically and then to automatically generate the model equations used by the predictive optimal controller. Additionally, PLIO can work off-line (in simulation) and on-line (in real-time mode). The case study of Santiago-Chile is presented to exemplify the control results obtained using PLIO off-line (in simulation).
Kerachian, Reza; Karamouz, Mohammad
2006-12-01
In this study, an algorithm combining a water quality simulation model and a deterministic/stochastic conflict resolution technique is developed for determining optimal reservoir operating rules. As different decision makers and stakeholders are involved in reservoir operation, the Nash bargaining theory is used to resolve the existing conflict of interests. The utility functions of the proposed models are developed on the basis of the reliability of the water supply to downstream demands, water storage, and the quality of the withdrawn water. The expected value on the Nash product is considered as the objective function of the stochastic model, which can incorporate the inherent uncertainty of reservoir inflow. A water quality simulation model is also developed to simulate the thermal stratification cycle and the reservoir discharge quality through a selective withdrawal structure. The optimization models are solved using a new version of genetic algorithms called varying chromosome length genetic algorithm (VLGA). In this algorithm the chromosome length is sequentially increased to provide a good initial solution for the final traditional GA-based optimization model. The proposed stochastic optimization model can also reduce the computational burden of the previously proposed models such as stochastic dynamic programming (SDP) by reducing the number of state transitions in each stage. The proposed models which are called VLGAQ and SVLGAQ are applied to the 15-Khordad Reservoir in the central part of Iran. The results show that the proposed models can reduce the salinity of allocated water to different water demands as well as the salinity buildup in the reservoir.
Directory of Open Access Journals (Sweden)
Wenpeng Yu
2013-12-01
Full Text Available Due to the interconnection and active management of Distributed Generation (DG and Energy Storage Systems (ESSs, the traditional electrical distribution network has become an Active Distribution Network (ADN, posing challenges to the operation optimization of the network. The power supply and storage capacity indexes of a Local Autonomy Control Region (LACR, which consists of DGs, ESSs and the network, are proposed in this paper to quantify the power regulating range of a LACR. DG/ESS and the network are considered as a whole in the model of the indexes, considering both network constraints and power constraints of the DG/ESS. The index quantifies the maximum LACR power supplied to or received from ADN lines. Similarly, power supply and storage capacity indexes of the ADN line are also proposed to quantify the maximum power exchanged between ADN lines. Then a practical algorithm to calculate the indexes is presented, and an operation optimization model is proposed based on the indexes to maximum the economic benefit of DG/ESS. In the optimization model, the power supply reliability of the ADN line is also considered. Finally, the indexes of power supply and storage capacity and the optimization are demonstrated in a case study.
Performance Optimization of Spin-Torque Microwave Detectors with Material and Operational Parameters
Directory of Open Access Journals (Sweden)
X. Li
2016-01-01
Full Text Available Sensitivity, bandwidth, and noise equivalent power (NEP are important indicators of the performance of microwave detectors. The previous reports on spin-torque microwave detectors (STMDs have proposed various approaches to increase the sensitivity. However, the effects of these methods on the other two indicators remain unclear. In this work, macrospin simulation is developed to evaluate how the performance can be optimized through changing the material (tilt angle of reference-layer magnetization and operational parameters (the direction of magnetic field and working temperature. The study on the effect of magnetic field reveals that the driving force behind the performance tuning is the effective field and the equilibrium angle between the magnetization of the free layer and that of the reference layer. The material that offers the optimal tilt angle in reference-layer magnetization is determined. The sensitivity can be further increased by changing the direction of the applied magnetic field and the operation temperature. Although the optimized sensitivity is accompanied by a reduction in bandwidth or an increase in NEP, a balance among these performance indicators can be reached through optimal tuning of the corresponding influencing parameters.
Energy Technology Data Exchange (ETDEWEB)
Katheder, H. [Max-Planck-Inst. fuer Plasmaphysik, Garching (Germany). NET Team
1995-12-31
Large superconducting coils such as are used for fusion experiments (Tokamak or Stellarator confiurations) are best equipped with internally cooled superconducting cables. These cables, which are cooled with helium at 4 K
Multicriteria Optimization of Gasification Operational Parameters Using a Pareto Genetic Algorithm
Directory of Open Access Journals (Sweden)
Miguel Caldas
2005-04-01
Full Text Available Gasification is a well-known technology that allows for a combustible gas to be obtained from a carbonaceous fuel by a partial oxidation process (POX. The resulting gas (synthesis gas or syngas can be used either as a fuel or as a feedstock for chemical production. Recently, gasification has also received a great deal of attention concerning power production possibilities through IGCC process (Integrated Gasification Combined Cycle, which is currently the most environmentally friendly and efficient method for the production of electricity. Gasification allows for low grade fuels, or dirty fuels, to be used in an environmental acceptable way. Amongst these fuels are wastes from the petrochemical and other industries, which vary in composition from shipment to shipment, and from lot to lot. If operating conditions are kept constant this could result in lose of efficiency. This paper presents an application of Genetic Algorithms to optimize the operating parameters of a gasifier processing a given fuel, so that the system achieves maximum efficiency for each particular fuel composition. A Pareto multiobjective optimization method, combined with a Genetic Algorithm, is applied to the simultaneous maximization of two different objective functions: Cold Gas Efficiency and Hydrogen Contents of the syngas. Results show that the optimization method developed is fast and simple enough to be used for on-line adjustment of the gasification operating parameters for each fuel composition and aim of gasification, thus improving overall performance of the industrial process.
Directory of Open Access Journals (Sweden)
Liudong Zhang
2014-01-01
Full Text Available An uncertain monthly reservoirs operation and multicrop deficit irrigation model was proposed under conjunctive use of underground and surface water for water resources optimization management. The objective is to maximize the total crop yield of the entire irrigation districts. Meanwhile, ecological water remained for the downstream demand. Because of the shortage of water resources, the monthly crop water production function was adopted for multiperiod deficit irrigation management. The model reflects the characteristics of water resources repetitive transformation in typical inland rivers irrigation system. The model was used as an example for water resources optimization management in Shiyang River Basin, China. Uncertainties in reservoir management shown as fuzzy probability were treated through chance-constraint parameter for decision makers. Necessity of dominance (ND was used to analyse the advantages of the method. The optimization results including reservoirs real-time operation policy, deficit irrigation management, and the available water resource allocation could be used to provide decision support for local irrigation management. Besides, the strategies obtained could help with the risk analysis of reservoirs operation stochastically.
Optimal Operation Method for Microgrid with Wind/PV/Diesel Generator/Battery and Desalination
Directory of Open Access Journals (Sweden)
Qingfeng Tang
2014-01-01
Full Text Available The power supply mode of island microgrid with a variety of complementary energy resources is one of the most effective ways to solve the problem of future island power supply. Based on the characteristics of seawater desalination system and water demand of island residents, a power allocation strategy for seawater desalination load, storage batteries, and diesel generators is proposed with the overall consideration of the economic and environmental benefits of system operation. Furthermore, a multiobjective optimal operation model for the island microgrid with wind/photovoltaic/diesel/storage and seawater desalination load is also proposed. It first establishes the objective functions which include the life loss of storage batteries and the fuel cost of diesel generators. Finally, the model is solved by the nondominated sorting genetic algorithm (NSGA-II. The island microgrid in a certain district is taken as an example to verify the effectiveness of the proposed optimal method. The results provide the theoretical and technical basis for the optimal operation of island microgrid.
Earnings and bank profitability in Nigeria
Directory of Open Access Journals (Sweden)
John N. N. Ugoani
2016-12-01
Full Text Available Bank earnings in form of retained profit help in the capital formation of banks. This is critical because capital inadequacy is often a cause of bank failures. During the banking crisis in Nigeria the gross earnings of many banks diminished considerably due to frauds and bad management. For example, in 2009 the Central Bank of Nigeria revoked the operating licences of fourteen banks which had huge nonperforming loans and were making losses. The fragility in the Nigerian banking system in the 1990s and beyond was compounded due to wide spread poor corporate governance practices and imprudent lending that led to the erosion of gross earnings and profitability. The study employed the exploratory research design. Data analyses were done through description statistics and the regression technique using the statistical package for the social sciences. The regression result was Y = 4.926 + 1.877x meaning that with an increase of 1 percent in gross earnings bank profitability increases by 1.88 percent. This is the crux of the study.
Braun, Robert Joseph
The advent of maturing fuel cell technologies presents an opportunity to achieve significant improvements in energy conversion efficiencies at many scales; thereby, simultaneously extending our finite resources and reducing "harmful" energy-related emissions to levels well below that of near-future regulatory standards. However, before realization of the advantages of fuel cells can take place, systems-level design issues regarding their application must be addressed. Using modeling and simulation, the present work offers optimal system design and operation strategies for stationary solid oxide fuel cell systems applied to single-family detached dwellings. A one-dimensional, steady-state finite-difference model of a solid oxide fuel cell (SOFC) is generated and verified against other mathematical SOFC models in the literature. Fuel cell system balance-of-plant components and costs are also modeled and used to provide an estimate of system capital and life cycle costs. The models are used to evaluate optimal cell-stack power output, the impact of cell operating and design parameters, fuel type, thermal energy recovery, system process design, and operating strategy on overall system energetic and economic performance. Optimal cell design voltage, fuel utilization, and operating temperature parameters are found using minimization of the life cycle costs. System design evaluations reveal that hydrogen-fueled SOFC systems demonstrate lower system efficiencies than methane-fueled systems. The use of recycled cell exhaust gases in process design in the stack periphery are found to produce the highest system electric and cogeneration efficiencies while achieving the lowest capital costs. Annual simulations reveal that efficiencies of 45% electric (LHV basis), 85% cogenerative, and simple economic paybacks of 5--8 years are feasible for 1--2 kW SOFC systems in residential-scale applications. Design guidelines that offer additional suggestions related to fuel cell
Truong, Binh Duc; Phu Le, Cuong; Halvorsen, Einar
2015-12-01
This paper presents experiments on how to approach the physical limits on power from vibration energy harvesting under displacement-constrained operation. A MEMS electrostatic vibration energy harvester with voltage-control of the system stiffness is used for this purpose. The power saturation problem, when the proof mass displacement reaches maximum amplitude for sufficient acceleration amplitude, is shifted to higher accelerations by use of load optimization and tunable electromechanical coupling k2. Measurement results show that harvested power can be made to follow the optimal velocity-damped generator also for a range of accelerations that implies displacement constraints. Comparing to the saturated power, the power increases 1.5 times with the optimal load and an electromechanical coupling k2=8.7%. This value is 2.3 times for a higher coupling k2=17.9%. The obtained system effectiveness is beyond 60% under the optimization. This work also shows a first demonstration of reaching optimal power in the intermediate acceleration-range between the two extremes of maximum efficiency and maximum power transfer.
Multiobjective Optimization of a Counterrotating Type Pump-Turbine Unit Operated at Turbine Mode
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Jin-Hyuk Kim
2014-05-01
Full Text Available A multiobjective optimization for improving the turbine output and efficiency of a counterrotating type pump-turbine unit operated at turbine mode was carried out in this work. The blade geometry of both the runners was optimized using a hybrid multiobjective evolutionary algorithm coupled with a surrogate model. Three-dimensional Reynolds-averaged Navier-Stokes equations with the shear stress transport turbulence model were discretized by finite volume approximations and solved on hexahedral grids to analyze the flow in the pump-turbine unit. As major hydrodynamic performance parameters, the turbine output and efficiency were selected as objective functions with two design variables related to the hub profiles of both the runner blades. These objectives were numerically assessed at twelve design points selected by Latin hypercube sampling in the design space. Response surface approximation models for the objectives were constructed based on the objective function values at the design points. A fast nondominated sorting genetic algorithm for the local search coupled with the response surface approximation models was applied to determine the global Pareto-optimal solutions. The trade-off between the two objectives was determined and described with respect to the Pareto-optimal solutions. The results of this work showed that the turbine outputs and efficiencies of optimized pump-turbine units were simultaneously improved in comparison to the reference unit.
Anghileri, D.; Castelletti, A.; Burlando, P.
2015-12-01
The recent spreading of renewable energy across Europe and the associated production variability and uncertainty are emerging challenges for hydropower system operation. Widely distributed and highly intermittent solar and wind power generation systems, along with feed-in-tariffs, at which they are remunerated, are threating the operation of traditional hydropower systems. For instance, in countries where the transition to a larger production by means of renewable power systems is a novel process, e.g. Switzerland, many hydropower companies are operating their reservoirs with low or no profits, claiming for a revision of the entire energy market system. This situation goes along with the problem of ensuring energy supply both nowadays and in the future, with changing energy demand and available water resources. In this work, we focus on a hydropower system in the Swiss Alps to explore how different operating policies can cope with both adequate energy supply and profitable operation under current and future climate and socio-economic conditions. We investigate the operation of the Mattmark reservoir in South-West Switzerland. Mattmark is a pumped reservoir of 98 106 m3 fed by a natural catchment of 37 km2 and contributing catchments, summing up to 51 km2, connected by several diversion channels. The hydrological regime, snow- and ice-melt dominated, has already experienced changes in the last decades due to glacier retreat and is expected to be strongly impacted by climate change in the future. We use Multi-Objective optimization techniques to explore current tradeoffs between profitability and secure supply. We then investigate how tradeoffs may evolve in time under different climate change projections and energy market scenarios. Results inform on the co-evolution of climate- and socio-economic induced variations, thus unveiling potential co-benefit situations to hydropower generation and providing insights to future energy market design.
Kiran, B. S.; Singh, Satyendra; Negi, Kuldeep
The GSAT-12 spacecraft is providing Communication services from the INSAT/GSAT system in the Indian region. The spacecraft carries 12 extended C-band transponders. GSAT-12 was launched by ISRO’s PSLV from Sriharikota, into a sub-geosynchronous Transfer Orbit (sub-GTO) of 284 x 21000 km with inclination 18 deg. This Mission successfully accomplished combined optimization of launch vehicle and satellite capabilities to maximize operational life of the s/c. This paper describes mission analysis carried out for GSAT-12 comprising launch window, orbital events study and orbit raising maneuver strategies considering various Mission operational constraints. GSAT-12 is equipped with two earth sensors (ES), three gyroscopes and digital sun sensor. The launch window was generated considering mission requirement of minimum 45 minutes of ES data for calibration of gyros with Roll-sun-pointing orientation in T.O. Since the T.O. period was a rather short 6.1 hr, required pitch biases were worked out to meet the gyro-calibration requirement. A 440 N Liquid Apogee Motor (LAM) is used for orbit raising. The objective of the maneuver strategy is to achieve desired drift orbit satisfying mission constraints and minimizing propellant expenditure. In case of sub-GTO, the optimal strategy is to first perform an in-plane maneuver at perigee to raise the apogee to synchronous level and then perform combined maneuvers at the synchronous apogee to achieve desired drift orbit. The perigee burn opportunities were examined considering ground station visibility requirement for monitoring the burn. Two maneuver strategies were proposed: an optimal five-burn strategy with two perigee burns centered around perigee#5 and perigee#8 with partial ground station visibility and three apogee burns with dual station visibility, a near-optimal five-burn strategy with two off-perigee burns at perigee#5 and perigee#8 with single ground station visibility and three apogee burns with dual station visibility
On the optimal determination of differential rates in the presence of higher-dimensional operators
Fichet, Sylvain; Rebello Teles, Patricia
2017-08-03
When the Standard Model is interpreted as the renormalizable sector of a low-energy effective theory, the effects of new physics are encoded into a set of higher-dimensional operators. These operators potentially deform the shapes of Standard Model differential distributions of final states observable at colliders. We describe a simple and systematic method to obtain optimal estimations of these deformations when using numerical tools, like Monte Carlo simulations. A crucial aspect of this method is minimization of the estimation uncertainty: we demonstrate how the operator coefficients have to be set in the simulations in order to get optimal results. The uncertainty on the interference term turns out to be the most difficult to control and grows very quickly when the interference is suppressed. We exemplify our method by computing the deformations induced by the ${\\cal O}_{3W}$ operator in $W^+W^-$ production at the LHC, and by deriving a bound on ${\\cal O}_{3W}$ using 8 TeV CMS data.
Energy Technology Data Exchange (ETDEWEB)
Ren, Hongbo [Ritsumeikan Global Innovation Research Organization, Ritsumeikan University, 603-8577 Kyoto (Japan); Zhou, Weisheng; Nakagami, Ken' ichi [College of Policy Sciences, Ritsumeikan University, 603-8577 Kyoto (Japan); Gao, Weijun; Wu, Qiong [Faculty of Environmental Engineering, The University of Kitakyushu, 808-0135 Kitakyushu (Japan)
2010-12-15
Along with the continuing global warming, the environmental constraints are expected to play more and more important role in the operation of distributed energy resource (DER) systems, besides the economic objective. In this study, a multi-objective optimization model is developed to analyze the optimal operating strategy of a DER system while combining the minimization of energy cost with the minimization of environmental impact which is assessed in terms of CO{sub 2} emissions. The trade-off curve is obtained by using the compromise programming method. As an illustrative example, the DER system installed in an eco-campus in Japan has been selected for case study. The distributed technologies under consideration include photovoltaics (PV), fuel cell and gas engine for providing electrical and thermal demands. The obtained results demonstrate that increasing the satisfaction degree of economic objective leads to increased CO{sub 2} emissions. The operation of the DER system is more sensitive when environmental objective is paid more attention. Moreover, according to the sensitivity analysis, the consideration of electricity buy-back, carbon tax, as well as fuel switching to biogas, has more or less effect on the operation of DER systems. (author)
Tsai, Wen-Ping; Chang, Fi-John; Chang, Li-Chiu; Herricks, Edwin E.
2015-11-01
Flow regime is the key driver of the riverine ecology. This study proposes a novel hybrid methodology based on artificial intelligence (AI) techniques for quantifying riverine ecosystems requirements and delivering suitable flow regimes that sustain river and floodplain ecology through optimizing reservoir operation. This approach addresses issues to better fit riverine ecosystem requirements with existing human demands. We first explored and characterized the relationship between flow regimes and fish communities through a hybrid artificial neural network (ANN). Then the non-dominated sorting genetic algorithm II (NSGA-II) was established for river flow management over the Shihmen Reservoir in northern Taiwan. The ecosystem requirement took the form of maximizing fish diversity, which could be estimated by the hybrid ANN. The human requirement was to provide a higher satisfaction degree of water supply. The results demonstrated that the proposed methodology could offer a number of diversified alternative strategies for reservoir operation and improve reservoir operational strategies producing downstream flows that could meet both human and ecosystem needs. Applications that make this methodology attractive to water resources managers benefit from the wide spread of Pareto-front (optimal) solutions allowing decision makers to easily determine the best compromise through the trade-off between reservoir operational strategies for human and ecosystem needs.
Subfield profitability analysis reveals an economic case for cropland diversification
Brandes, E.; McNunn, G. S.; Schulte, L. A.; Bonner, I. J.; Muth, D. J.; Babcock, B. A.; Sharma, B.; Heaton, E. A.
2016-01-01
Public agencies and private enterprises increasingly desire to achieve ecosystem service outcomes in agricultural systems, but are limited by perceived conflicts between economic and ecosystem service goals and a lack of tools enabling effective operational management. Here we use Iowa—an agriculturally homogeneous state representative of the Maize Belt—to demonstrate an economic rationale for cropland diversification at the subfield scale. We used a novel computational framework that integrates disparate but publicly available data to map ˜3.3 million unique potential management polygons (9.3 Mha) and reveal subfield opportunities to increase overall field profitability. We analyzed subfield profitability for maize/soybean fields during 2010-2013—four of the most profitable years in recent history—and projected results for 2015. While cropland operating at a loss of US 250 ha-1 or more was negligible between 2010 and 2013 at 18 000-190 000 ha (profitable areas, incorporating conservation management that breaks even (e.g., planting low-input perennials), into low-yielding portions of fields could increase overall cropland profitability by 80%. This approach is applicable to the broader region and differs substantially from the status quo of ‘top-down’ land management for conservation by harnessing private interest to align profitability with the production of ecosystem services.
The Determinants of Bank Profitability: The Case of Tunisia
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Olfa Nessibi
2016-01-01
Full Text Available Using bank level data this paper examines how bank’s specific characteristics and macroeconomic indicators affect the profitability in the Tunisian banking industry over the period 1990–2008. The results indicate that the more profitable banks are those higher amount of capital and lower operating costs. Furthermore, it appears that private banks tend to perform better than state owned ones. Despite the great importance given to the board of directors, it doesn't have a dominant role in the Tunisian commercial banks. Finally, turning to macroeconomic conditions and its impact on banks’ profitability, we find that the real interest rate has a positive effect on bank profitability.
A study on relationship between working capital and profitability
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Hassan Ghodrati
2014-08-01
Full Text Available This paper studies the relationship between working capital management and profitability of accepted corporations in Tehran Stock Exchange over the period 2008-2012. The study selected 66 firms as a statistical sample based on Cochran formula and simple random selection. In this study, variables including the average period of collecting accordance, periods of circulation of inventories, the average period of debt payment, and cycle of cash conversion on the factories operating profits are studied. The research method is applied and collection of data is solidarity, the Pierson and Regression solidarity are used. Results show that variables of capital investment management and profitability were in opposite direction. If the period of collecting accordance, period of debt payment, period of circulation of inventories and the cycle of cash conversion increase, it decreases the period profitability and the manager can decrease the period of debt payment, period of cash conversion to the least amount of positive value for affiliate.
Optimizing the CEBAF Injector for Beam Operation with a Higher Voltage Electron Gun
Hannon, F E; Kazimi, R
2011-01-01
Recent developments in the DC gun technology used at CEBAF have allowed an increase in operational voltage from 100kV to 130kV. In the near future this will be extended further to 200kV with the purchase of a new power supply. The injector components and layout at this time have been designed specifically for 100kV operation. It is anticipated that with an increase in gun voltage and optimization of the layout and components for 200kV operation, that the electron bunch length and beam brightness can be improved upon. This paper explores some upgrade possibilities for a 200kV gun CEBAF injector through beam dynamic simulations.
Energy Technology Data Exchange (ETDEWEB)
Xu, Wu; Xiao, Jie; Zhang, Jian; Wang, Deyu; Zhang, Jiguang
2009-07-07
The selection and optimization of non-aqueous electrolytes for ambient operations of lithium/air batteries has been studied. Organic solvents with low volatility and low moisture absorption are necessary to minimize the change of electrolyte compositions and the reaction between lithium anode and water during discharge process. It is critical to make the electrolytes with high polarity so that it can reduce wetting and flooding of carbon based air electrode and lead to improved battery performance. For ambient operations, the viscosity, ionic conductivity, and oxygen solubility of the electrolyte are less important than the polarity of organic solvents once the electrolyte has reasonable viscosity, conductivity, and oxygen solubility. It has been found that PC/EC mixture is the best solvent system and LiTFSI is the most feasible salt for ambient operations of Li/air batteries. Battery performance is not very sensitive to PC/EC ratio or salt concentration.
Institute of Scientific and Technical Information of China (English)
无
2006-01-01
The recurrent neural network (RNN) model based on projective operator was studied. Different from the former study, the value region of projective operator in the neural network in this paper is a general closed convex subset of n-dimensional Euclidean space and it is not a compact convex set in general, that is, the value region of projective operator is probably unbounded. It was proved that the network has a global solution and its solution trajectory converges to some equilibrium set whenever objective function satisfies some conditions. After that, the model was applied to continuously differentiable optimization and nonlinear or implicit complementarity problems. In addition, simulation experiments confirm the efficiency of the RNN.
Ishii, Shun'ichi; Suzuki, Shino; Norden-Krichmar, Trina M; Wu, Angela; Yamanaka, Yuko; Nealson, Kenneth H; Bretschger, Orianna
2013-12-01
Microbial fuel cells (MFCs) are devices that exploit microorganisms as "biocatalysts" to recover energy from organic matter in the form of electricity. MFCs have been explored as possible energy neutral wastewater treatment systems; however, fundamental knowledge is still required about how MFC-associated microbial communities are affected by different operational conditions and can be optimized for accelerated wastewater treatment rates. In this study, we explored how electricity-generating microbial biofilms were established at MFC anodes and responded to three different operational conditions during wastewater treatment: 1) MFC operation using a 750 Ω external resistor (0.3 mA current production); 2) set-potential (SP) operation with the anode electrode potentiostatically controlled to +100 mV vs SHE (4.0 mA current production); and 3) open circuit (OC) operation (zero current generation). For all reactors, primary clarifier effluent collected from a municipal wastewater plant was used as the sole carbon and microbial source. Batch operation demonstrated nearly complete organic matter consumption after a residence time of 8-12 days for the MFC condition, 4-6 days for the SP condition, and 15-20 days for the OC condition. These results indicate that higher current generation accelerates organic matter degradation during MFC wastewater treatment. The microbial community analysis was conducted for the three reactors using 16S rRNA gene sequencing. Although the inoculated wastewater was dominated by members of Epsilonproteobacteria, Gammaproteobacteria, and Bacteroidetes species, the electricity-generating biofilms in MFC and SP reactors were dominated by Deltaproteobacteria and Bacteroidetes. Within Deltaproteobacteria, phylotypes classified to family Desulfobulbaceae and Geobacteraceae increased significantly under the SP condition with higher current generation; however those phylotypes were not found in the OC reactor. These analyses suggest that species
Institute of Scientific and Technical Information of China (English)
刘嫣; 齐璐璐; 朱骞; 朱同玉
2014-01-01
Objective:To indicate the difficulties of operating private non-profit hospitals by a comparative study of a private non-profit hospital and a public hospital in the economic performance and the social benefits. Methods:In-depth interviews and a questionnaire survey were conducted to analyze the economic performance and the social benefits of a private non-profit hospital and a public hospital. Results:Between the private non-profit hospital and the public hospital,there were differences in the economic performance and the sustainable development ability. Conclusion:Public hospitals surpass private non-profit hospitals in the economic performance and sustainable development ability.%目的：比较两家不同举办主体的医疗机构在经济运行情况和社会效益方面的差异，揭示社会资本办医之困境。方法：通过深度访谈和问卷调查，对两家医院经济运行和社会效益等指标和数据进行描述性分析。结果：两家不同举办主体的医疗机构，在经济运行状况和持续发展能力方面存在差异。结论：公立医院的经济运行状况和持续发展能力好于民营医院。
Institute of Scientific and Technical Information of China (English)
2006-01-01
Accounting methods in state-owned enterprises leave much to be desired. A recent initiative aimed at a professional management audit could soon change this China’s state-owned enterprises (SOEs) present a strange dilemma-they are making profits but also draining state assets. This has prompted the National Audit Office to set the examination of SOEs’ financial accounts as a key task for this year. According to a Ministry of Finance report in February, performance of Chinese SOEs maintained stable growth in 2005, generating 900 billion yuan in profits, a year-on-year increase of 25 percent. A comparison of figures in recent years shows rising profits in key
Cost analysis helps evaluate contract profitability.
Sides, R W
2000-02-01
A cost-accounting analysis can help group practices assess their costs of doing business and determine the profitability of managed care contracts. Group practices also can use cost accounting to develop budgets and financial benchmarks. To begin a cost analysis, group practices need to determine their revenue and cost centers. Then they can allocate their costs to each center, using an appropriate allocation basis. The next step is to calculate costs per procedure. The results can be used to evaluate operational cost efficiency as well as help negotiate managed care contracts.
Directory of Open Access Journals (Sweden)
Malek Jasemi
2016-11-01
Full Text Available Nowadays, due to technical and economic reasons, the distributed generation (DG units are widely connected to the low and medium voltage network and created a new structure called micro-grid. Renewable energies (especially wind and solar based DGs are one of the most important generations units among DG units. Because of stochastic behavior of these resources, the optimum and safe management and operation of micro-grids has become one of the research priorities for researchers. So, in this study, the optimal operation of a typical micro-grid is investigated in order to maximize the penetration of renewable energy sources with the lowest operation cost with respect to the limitations for the load supply and the distributed generation resources. The understudy micro-grid consists of diesel generator, battery, wind turbines and photovoltaic panels. The objective function comprises of fuel cost, start-up cost, spinning reserve cost, power purchasing cost from the upstream grid and the sales revenue of the power to the upstream grid. In this paper, the uncertainties of demand, wind speed and solar radiation are considered and the optimization will be made by using the GAMS software and mixed integer planning method (MIP. Article History: Received May 21, 2016; Received in revised form July 11, 2016; Accepted October 15, 2016; Available online How to Cite This Article: Jasemi, M., Adabi, F., Mozafari, B., and Salahi, S. (2016 Optimal Operation of Micro-grids Considering the Uncertainties of Demand and Renewable Energy Resources Generation, Int. Journal of Renewable Energy Development, 5(3,233-248. http://dx.doi.org/10.14710/ijred.5.3.233-248
Meet the New For-Profit: The Low-Profit
Blumenstyk, Goldie
2012-01-01
"Doing well by doing good" is the business mantra of the for-profit-college industry. But one does not have to look far to find people who question the slogan's sincerity or the very legitimacy of that model. And that was even before reports of some companies' abusive student-recruiting practices and questionable educational standards fed a public…
A Dynamic Optimization Strategy for the Operation of Large Scale Seawater Reverses Osmosis System
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Aipeng Jiang
2014-01-01
Full Text Available In this work, an efficient strategy was proposed for efficient solution of the dynamic model of SWRO system. Since the dynamic model is formulated by a set of differential-algebraic equations, simultaneous strategies based on collocations on finite element were used to transform the DAOP into large scale nonlinear programming problem named Opt2. Then, simulation of RO process and storage tanks was carried element by element and step by step with fixed control variables. All the obtained values of these variables then were used as the initial value for the optimal solution of SWRO system. Finally, in order to accelerate the computing efficiency and at the same time to keep enough accuracy for the solution of Opt2, a simple but efficient finite element refinement rule was used to reduce the scale of Opt2. The proposed strategy was applied to a large scale SWRO system with 8 RO plants and 4 storage tanks as case study. Computing result shows that the proposed strategy is quite effective for optimal operation of the large scale SWRO system; the optimal problem can be successfully solved within decades of iterations and several minutes when load and other operating parameters fluctuate.
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A.Thillaivanan,
2010-12-01
Full Text Available In this paper the complexity of electrical discharge machining process which is very difficult to determine optimal cutting parameters for improving cutting performance has been reported. Optimization of operating parameters is an important step in machining, particularly for operating unconventional machiningprocedure like EDM. A suitable selection of machining parameters for the electrical discharge machining process relies heavily on the operators’ technologies and experience because of their numerous and diverse range. Machining parameters tables provided by the machine tool builder can not meet the operators’ requirements, since for anarbitrary desired machining time for a particular job, they do not provide the optimal machining conditions. An approach to determine parameters setting is proposed. Based on the Taguchi parameter design method and the analysis of variance, the significant factors affecting the machining performance such as total machining time, oversize and taper for a hole machined by EDM process, are determined.Artificial neural networks are highly flexible modeling tools with an ability to learn the mapping between input variables and output feature spaces. The superiority of using artificial neural networks inmodeling machining processes make easier to model the EDM process with dimensional input and output spaces. On the basis of the developed neural network model, for a required total machining time, oversize and taper the corresponding process parameters to be set in EDM by using the developed and trained ANN are determined.
Energy Technology Data Exchange (ETDEWEB)
Makeechev, V.A. [Industrial Power Company, Krasnopresnenskaya Naberejnaya 12, 123610 Moscow (Russian Federation); Soukhanov, O.A. [Energy Systems Institute, 1 st Yamskogo Polya Street 15, 125040 Moscow (Russian Federation); Sharov, Y.V. [Moscow Power Engineering Institute, Krasnokazarmennaya Street 14, 111250 Moscow (Russian Federation)
2008-07-15
This paper presents foundations of the optimization method intended for solution of power systems operation problems and based on the principles of functional modeling (FM). This paper also presents several types of hierarchical FM algorithms for economic dispatch in these systems derived from this method. According to the FM method a power system is represented by hierarchical model consisting of systems of equations of lower (subsystem) levels and higher level system of connection equations (SCE), in which only boundary variables of subsystems are present. Solution of optimization problem in accordance with the FM method consists of the following operations: (1) solution of optimization problem for each subsystem (values of boundary variables for subsystems should be determined on the higher level of model); (2) calculation of functional characteristic (FC) of each subsystem, pertaining to state of subsystem on current iteration (these two steps are carried out on the lower level of the model); (3) formation and solution of the higher level system of equations (SCE), which gives values of boundary and supplementary boundary variables on current iteration. The key elements in the general structure of the FM method are FCs of subsystems, which represent them on the higher level of the model as ''black boxes''. Important advantage of hierarchical FM algorithms is that results obtained with them on each iteration are identical to those of corresponding basic one level algorithms. (author)
Directory of Open Access Journals (Sweden)
Tilahun Derib Asfaw
2013-07-01
Full Text Available The operation of the four Perak cascading reservoirs namely, Temenggor, Bersia, Kenering and Chenderoh analyzed using the newly developed genetic algorithm model. The reservoirs are located in the state of Perak of Peninsular Malaysia that used for hydroelectric power generation and flood mitigation. The hydroelectric potential of the cascading scheme is 578 MW. However, the actual annual average generation was 228 MW, which is about 39% of the potential. The research aimed to improve the annual average hydroelectric power generation. The result of the fitness value used to select the optimal option from the test of eight model runs options. After repeated runs of the optimal option, the best model parameters are found. Therefore, optimality achieved at population size of 150, crossover probability of 0.75 and generation number of 60. The operation of GA model produced an additional of 12.17 MW per day. The additional power is found with the same total annual volume of release and similar natural inflow pattern. The additional hydroelectric power can worth over 22 million Ringgit Malaysia per year. In addition, it plays a significant role on the growing energy needs of the country.
Energy Technology Data Exchange (ETDEWEB)
Moeini, R.; Afshar, M.H.
2011-07-15
Hydropower is currently the number one source of electricity production in the world. For the design and construction of such systems, mathematical modelling is often use for reservoir operations. As conventional methods present some shortcomings in solving reservoir operation problems, a new method is presented here. It consists in an arc-based formulation of hydropower reservoir operation problems which can be applied to ant colony optimization algorithms. This paper first described this formulation and then applied it to solve two hydropower reservoir operation problems. The results showed that this formulation can optimally solve large-scale hydropower reservoir operation problems while offering a clear definition of heuristic information.
Directory of Open Access Journals (Sweden)
Alireza Fazlali
2010-01-01
Full Text Available While energy prices continue to climb, it conservation remains the prime concern for process industries. The daily growth of energy consumption throughout the world and the real necessity of providing it, shows that optimization of energy generation and consumption units is an economical and sometimes vital case. Hence, the optimization of a petroleum refinery is aimed towards great production and an increase in quality. In this research, the atmospheric distillation unit of the Iran-Arak-Shazand petroleum refinery was subject to optimization efforts. It was performed by the means of using a simulator with the aim to earn more overhead products. In the next step the optimization results from the simulators were carried out in the real world, at the above mentioned unit. Results demonstrate that the changes in the real operating conditions increase the overhead products with desirable quality. Finally, a net economical balance between the increments of the overhead products and the energy consumption shows an energy saving in this refinery.
Energy Technology Data Exchange (ETDEWEB)
Zheng, Xiaoyu; Ishikawa, Jun; Sugiyama, Tomoyuki; Maryyama, Yu [Nuclear Safety Research Center, Japan Atomic Energy Agency, Ibaraki (Japan)
2017-03-15
Containment venting is one of several essential measures to protect the integrity of the final barrier of a nuclear reactor during severe accidents, by which the uncontrollable release of fission products can be avoided. The authors seek to develop an optimization approach to venting operations, from a simulation-based perspective, using an integrated severe accident code, THALES2/KICHE. The effectiveness of the containment-venting strategies needs to be verified via numerical simulations based on various settings of the venting conditions. The number of iterations, however, needs to be controlled to avoid cumbersome computational burden of integrated codes. Bayesian optimization is an efficient global optimization approach. By using a Gaussian process regression, a surrogate model of the “black-box” code is constructed. It can be updated simultaneously whenever new simulation results are acquired. With predictions via the surrogate model, upcoming locations of the most probable optimum can be revealed. The sampling procedure is adaptive. Compared with the case of pure random searches, the number of code queries is largely reduced for the optimum finding. One typical severe accident scenario of a boiling water reactor is chosen as an example. The research demonstrates the applicability of the Bayesian optimization approach to the design and establishment of containment-venting strategies during severe accidents.
Ertas, Nevbahar; Roch, Christine H.
2014-01-01
For-profit educational management organizations (EMOs) are a growing phenomenon in public education, and they are an integral part of charter school reform in many states. Research suggests that charter schools operated by for-profit entities may take a more entrepreneurial approach when expanding their operations and thus may be more inclined to…
Ertas, Nevbahar; Roch, Christine H.
2014-01-01
For-profit educational management organizations (EMOs) are a growing phenomenon in public education, and they are an integral part of charter school reform in many states. Research suggests that charter schools operated by for-profit entities may take a more entrepreneurial approach when expanding their operations and thus may be more inclined to…
Optimization of the Waterbus Operation Plan Considering Carbon Emissions: The Case of Zhoushan City
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Juying Wang
2015-08-01
Full Text Available Recently, as more people are concerned with the issues around environment protection, research about how to reduce carbon emissions has drawn increasing attention. Encouraging public transportation is an effective measure to reduce carbon emissions. However, overland public transportation does less to lower carbon because of the gradually increasing pressure of the urban road traffic. Therefore, the waterbus along the coast becomes a new direction of the urban public transport development. In order to optimize the operation plan of the waterbus, a bi-level model considering carbon emissions is proposed in this paper. In the upper-level model, a multiple objective model is established, which considers both the interests of the passengers and the operator while considering the carbon emissions. The lower-level model is a traffic model split by using a Nested Logit model. A NSGA-II (Non-dominated Sorting Genetic Algorithm-II algorithm is proposed to solve the model. Finally, the city of Zhoushan is chosen as an example to prove the feasibility of the model and the algorithm. The result shows that the proposed model for waterbus operation optimization can efficiently reduce transportation carbon emissions and satisfy passenger demand at the same time.
Energy Technology Data Exchange (ETDEWEB)
Aoyama, H.
2000-07-01
Based on consulting service RPS-J under joint operation of Nikki, UOP LLC of U.S.A. and Nikki Universal, approaching ways applied for profitability improvement and improvement proposal for refineries and analyzing techniques used for resolution of process bottlenecks were described. In RPS-J, themes of (1) energy saving, (2) quality upgrading, (3) improvement of disintegrating ratio, (4) reduction of give-away, (5) improvement of equipment operation ratio, (6) reduction of maintenance cost, (7) effective utilization of catalysts, are considered for profitability improvement fields. Procedures from idea excavation for profitability improvement to realization of profitability improvement are carried out in the order of, (1) Grasping of the present state, (2) Excavation of improving items and selection, (3) Quantitative evaluation of draft profitability improvement plan and focusing, (4) Profitability improvement by operation improvement, (5) Profitability improvement by minor improvement, (6) Profitability improvement in middle- and long-term vision, (7) Final focusing by feasibility study. Afterwards, examination to economically solve bottlenecks of critical facilities, examination on bottlenecks of distillation tower and refining tower and utility analysis are carried out. RPS-J was already applied to 4 refineries including Muroran Refinery and Negishi Refinery of Nisseki Mitsubishi, and profitability improvement themes were found to improve profitability of 50 to 150 cents per barrel. (NEDO)
An operational rate-distortion optimal single-pass SNR scalable video coder.
Kondi, L P; Katsaggelos, A K
2001-01-01
In this paper, we introduce a new methodology for signal-to-noise ratio (SNR) video scalability based on the partitioning of the DCT coefficients. The DCT coefficients of the displaced frame difference (DFD) for inter-blocks or the intensity for intra-blocks are partitioned into a base layer and one or more enhancement layers, thus, producing an embedded bitstream. Subsets of this bitstream can be transmitted with increasing video quality as measured by the SNR. Given a bit budget for the base and enhancement layers the partitioning of the DCT coefficients is done in a way that is optimal in the operational rate-distortion sense. The optimization is performed using Lagrangian relaxation and dynamic programming (DP). Experimental results are presented and conclusions are drawn.
Feedback Control Method Using Haar Wavelet Operational Matrices for Solving Optimal Control Problems
Directory of Open Access Journals (Sweden)
Waleeda Swaidan
2013-01-01
Full Text Available Most of the direct methods solve optimal control problems with nonlinear programming solver. In this paper we propose a novel feedback control method for solving for solving affine control system, with quadratic cost functional, which makes use of only linear systems. This method is a numerical technique, which is based on the combination of Haar wavelet collocation method and successive Generalized Hamilton-Jacobi-Bellman equation. We formulate some new Haar wavelet operational matrices in order to manipulate Haar wavelet series. The proposed method has been applied to solve linear and nonlinear optimal control problems with infinite time horizon. The simulation results indicate that the accuracy of the control and cost can be improved by increasing the wavelet resolution.
Many-body decoherence dynamics and optimized operation of a single-photon switch
Murray, C. R.; Gorshkov, A. V.; Pohl, T.
2016-09-01
We develop a theoretical framework to characterize the decoherence dynamics due to multi-photon scattering in an all-optical switch based on Rydberg atom induced nonlinearities. By incorporating the knowledge of this decoherence process into optimal photon storage and retrieval strategies, we establish optimized switching protocols for experimentally relevant conditions, and evaluate the corresponding limits in the achievable fidelities. Based on these results we work out a simplified description that reproduces recent experiments (Nat. Commun. 7 12480) and provides a new interpretation in terms of many-body decoherence involving multiple incident photons and multiple gate excitations forming the switch. Aside from offering insights into the operational capacity of realistic photon switching capabilities, our work provides a complete description of spin wave decoherence in a Rydberg quantum optics setting, and has immediate relevance to a number of further applications employing photon storage in Rydberg media.
Optimal Constant DC Link Voltage Operation of aWave Energy Converter
Directory of Open Access Journals (Sweden)
Mats Leijon
2013-04-01
Full Text Available This article proposes a simple and reliable damping strategy for wave powerfarm operation of small-scale point-absorber converters. The strategy is based on passiverectification onto a constant DC-link, making it very suitable for grid integration of the farm.A complete model of the system has been developed in Matlab Simulink, and uses real sitedata as input. The optimal constant DC-voltage is evaluated as a function of the significantwave height and energy period of the waves. The total energy output of the WEC is derivedfor one year of experimental site data. The energy output is compared for two cases, onewhere the optimal DC-voltage is determined and held constant at half-hour basis throughoutthe year, and one where a selected value of the DC-voltage is kept constant throughout theyear regardless of sea state.
An Operation Optimization for Express Freight Trains Based on Shipper Demands
Directory of Open Access Journals (Sweden)
Yuzhao Zhang
2014-01-01
Full Text Available The supreme goal of railway express freight transportation is to meet the various demands of shippers. This paper considers the optimization problem of the operation plan for express freight trains based on shipper demands, including transport volume, service frequency, and transit time. An integer programming model that takes maximum shipper demands as optimized objective is proposed to realize the assignment of trains to candidate paths. In this model, the number of marshalling cars for express freight train is set as a decision variable rather than a constant to better satisfy the demand characteristics. A heuristic solution algorithm based on genetic algorithm is then designed. Finally, a numerical case is applied to verify the feasibility of the model and the algorithm.
Determination of the Cascade Reservoir Operation for Optimal Firm-Energy Using Genetic Algorithms
Directory of Open Access Journals (Sweden)
Azmeri
2013-08-01
Full Text Available Indonesia today face a new paradigm in water management where aim to apply integrated water resources management has become unavoidable task in purpose of achieving greater level of effectiveness and efficiency. On of most interesting case study is the case of Citarum river, one of the most potential river for water supply in West Java, Indonesia. Alongside the river, Saguling, Cirata and Djuanda Reservoirs had been constructed in series/cascade. Saguling and Cirata reservoirs are particularly operated for hydroelectric power and Djuanda is multipurpose reservoir mainly operated for irrigation and contribute domestic water supply for Jakarta (capital city of Indonesia. Basically all reservoirs are relying on same resources, therefore this condition has considered addressing management and operational problem. Therefore, an approach toward new management and operation system are urgently required in order to achieve the effective and efficient output and to avoid conflicts of water used. This study aims to obtain energy production from Citarum Cascade Reservoir System using Genetic Algorithms optimization with the objective function to maximize firm-energy. Firm-energy is the minimum energy requirements must be available in a certain time period. Then, the result obtained by using the energy produced by GA is compared to the conventional searching technique of Non-Linier Programming (NLP. The GA derived operating curves reveal the higher energy and firm-energy than NLP model
Improving operability of spouted beds using a simple optimizing control structure
Directory of Open Access Journals (Sweden)
N. A. CORRÊA
1999-12-01
Full Text Available In operations using spouted beds, it is of major importance, from an energy consumption point of view, to operate the process as close as possible to the minimum spout flow. At this point, the speed of the gas (for example, warm air in drying operations is greater than the amount of heat and mass transfer involved, although it only transfers the minimum amount of momentum to maintain the spout. Therefore, by staying close to this minimum flow condition, it is possible to perform a stable operation and to obtain energy savings not only in the heating of the gas but also in its displacement by blowers. In order to improve the operation of such processes, a study is carried out by implementing a simple optimizing control structure on a spouted bed experimental set-up. The air flow is regulated by a frequency inverter, at the speed of blower rotation. A PI controller was used and the set-point for the air flow rate is calculated on-line by a simple and well-known minimization method called Golden Section Search. This set-point is constantly updated with values very close to the actual minimum spout flow rate. To accomplish the calculations and data acquisitions, a microcomputer with an interface and an analog signal conditioner is used .
Energy Technology Data Exchange (ETDEWEB)
Johnson, David K; Lewis, Matthew J; Pavlich, Jane C; Wright, Alan D; Johnson, Kathryn E; Pace, Andrew M
2013-02-01
The goal of this Department of Energy (DOE) project is to increase wind turbine efficiency and reliability with the use of a Light Detection and Ranging (LIDAR) system. The LIDAR provides wind speed and direction data that can be used to help mitigate the fatigue stress on the turbine blades and internal components caused by wind gusts, sub-optimal pointing and reactionary speed or RPM changes. This effort will have a significant impact on the operation and maintenance costs of turbines across the industry. During the course of the project, Michigan Aerospace Corporation (MAC) modified and tested a prototype direct detection wind LIDAR instrument; the resulting LIDAR design considered all aspects of wind turbine LIDAR operation from mounting, assembly, and environmental operating conditions to laser safety. Additionally, in co-operation with our partners, the National Renewable Energy Lab and the Colorado School of Mines, progress was made in LIDAR performance modeling as well as LIDAR feed forward control system modeling and simulation. The results of this investigation showed that using LIDAR measurements to change between baseline and extreme event controllers in a switching architecture can reduce damage equivalent loads on blades and tower, and produce higher mean power output due to fewer overspeed events. This DOE project has led to continued venture capital investment and engagement with leading turbine OEMs, wind farm developers, and wind farm owner/operators.
Decker, Frederic H
2008-04-01
Poorer resident care in US for-profit relative to not-for-profit nursing homes is usually blamed on the profit motive. But US nursing home performance may relate to Medicaid public financing in a manner qualifying the relationship between ownership and quality. We investigated effects of Medicaid resident census, Medicaid payment, and occupancy on performance. Resource dependence theory implies these predictors may affect discretion in resources invested in resident care across for-profit and not-for-profit facilities. Models on physical restraint use and registered nurse (RN) staffing were studied using generalized estimating equations with panel data derived from certification inspections of nursing homes. Restraint use increased and RN staffing levels decreased among for-profit and not-for-profit facilities when the Medicaid census increased and Medicaid payment decreased. Interaction effects supported a theory that performance relates to available discretion in resource allocation. Effects of occupancy appear contingent on the dependence on Medicaid. Poorer performance among US for-profit nursing homes may relate to for-profit homes having lower occupancy, higher Medicaid census, and operating in US states with lower Medicaid payments compared to not-for-profit homes. Understanding the complexity of factors affecting resources expended on resident care may further our understanding of the production of quality in nursing homes, whether in the US or elsewhere.
Ike, Innocent S.; Sigalas, Iakovos; Iyuke, Sunny E.
2017-03-01
Theoretical expressions for performance parameters of different electrochemical capacitors (ECs) have been optimized by solving them using MATLAB scripts as well as via the MATLAB R2014a optimization toolbox. The performance of the different kinds of ECs under given conditions was compared using theoretical equations and simulations of various models based on the conditions of device components, using optimal values for the coefficient associated with the battery-kind material ( K BMopt) and the constant associated with the electrolyte material ( K Eopt), as well as our symmetric electric double-layer capacitor (EDLC) experimental data. Estimation of performance parameters was possible based on values for the mass ratio of electrodes, operating potential range ratio, and specific capacitance of electrolyte. The performance of asymmetric ECs with suitable electrode mass and operating potential range ratios using aqueous or organic electrolyte at appropriate operating potential range and specific capacitance was 2.2 and 5.56 times greater, respectively, than for the symmetric EDLC and asymmetric EC using the same aqueous electrolyte, respectively. This enhancement was accompanied by reduced cell mass and volume. Also, the storable and deliverable energies of the asymmetric EC with suitable electrode mass and operating potential range ratios using the proper organic electrolyte were 12.9 times greater than those of the symmetric EDLC using aqueous electrolyte, again with reduced cell mass and volume. The storable energy, energy density, and power density of the asymmetric EDLC with suitable electrode mass and operating potential range ratios using the proper organic electrolyte were 5.56 times higher than for a similar symmetric EDLC using aqueous electrolyte, with cell mass and volume reduced by a factor of 1.77. Also, the asymmetric EDLC with the same type of electrode and suitable electrode mass ratio, working potential range ratio, and proper organic electrolyte
Optimizing the domain wall fermion Dirac operator using the R-Stream source-to-source compiler
Lin, Meifeng; Langston, M Harper; Meister, Benoit; Baskaran, Muthu; Izubuchi, Taku; Jung, Chulwoo
2015-01-01
The application of the Dirac operator on a spinor field, the Dslash operation, is the most computation-intensive part of the lattice QCD simulations. It is often the key kernel to optimize to achieve maximum performance on various platforms. Here we report on a project to optimize the domain wall fermion Dirac operator in Columbia Physics System (CPS) using the R-Stream source-to-source compiler. Our initial target platform is the Intel PC clusters. We discuss the optimization strategies involved before and after the automatic code generation with R-Stream and present some preliminary benchmark results.
MagRad: A code to optimize the operation of superconducting magnets in a radiation environment
Energy Technology Data Exchange (ETDEWEB)
Yeaw, Christopher T. [Univ. of Wisconsin, Madison, WI (United States)
1995-01-01
A powerful computational tool, called MagRad, has been developed which optimizes magnet design for operation in radiation fields. Specifically, MagRad has been used for the analysis and design modification of the cable-in-conduit conductors of the TF magnet systems in fusion reactor designs. Since the TF magnets must operate in a radiation environment which damages the material components of the conductor and degrades their performance, the optimization of conductor design must account not only for start-up magnet performance, but also shut-down performance. The degradation in performance consists primarily of three effects: reduced stability margin of the conductor; a transition out of the well-cooled operating regime; and an increased maximum quench temperature attained in the conductor. Full analysis of the magnet performance over the lifetime of the reactor includes: radiation damage to the conductor, stability, protection, steady state heat removal, shielding effectiveness, optimal annealing schedules, and finally costing of the magnet and reactor. Free variables include primary and secondary conductor geometric and compositional parameters, as well as fusion reactor parameters. A means of dealing with the radiation damage to the conductor, namely high temperature superconductor anneals, is proposed, examined, and demonstrated to be both technically feasible and cost effective. Additionally, two relevant reactor designs (ITER CDA and ARIES-II/IV) have been analyzed. Upon addition of pure copper strands to the cable, the ITER CDA TF magnet design was found to be marginally acceptable, although much room for both performance improvement and cost reduction exists. A cost reduction of 10-15% of the capital cost of the reactor can be achieved by adopting a suitable superconductor annealing schedule. In both of these reactor analyses, the performance predictive capability of MagRad and its associated costing techniques have been demonstrated.
DEFF Research Database (Denmark)
Grønholdt, Lars; Martensen, Anne
2016-01-01
to demonstrate such links, and several issues must be addressed to uncover the links. To investigate these links empirically, a hotel chain provided data matching employee and customer measures with measures of profitability. We have successfully employed a modeling approach, and the paper reports empirical...
Hayes, Dianne
2012-01-01
Amid numerous efforts to increase college-going and completion rates among minority students, for-profit institutions stand out as a leader in that regard. Class flexibility for working and non-traditional students, online courses, and corporate partnerships to reimburse employees are all contributing factors to their appeal. However, along with…
Modeling and Optimal Operation of Distributed Battery Storage in Low Voltage Grids
Fortenbacher, Philipp; Mathieu, Johanna L.; Andersson, Göran
2016-01-01
Due to high power in-feed from photovoltaics, it can be expected that more battery systems will be installed in the distribution grid in near future to mitigate voltage violations and thermal line and transformer overloading. In this paper, we present a two-stage centralized model predictive control scheme for distributed battery storage that consists of a scheduling entity and a real-time control entity. To guarantee secure grid operation, we solve a robust multi-period optimal power flow (O...
Developing Virtual Power Plant for Optimized Distributed Energy Resources Operation and Integration
You, Shi; Træholt, Chresten; Poulsen, Bjarne
2010-01-01
Distributed Energy Resources (DER) are small-scale power generation and storage technologies, (typically in the range of a few kWe to tens of kWe) located close to the customer side. They are right now under heavy development and have a great market potential in the near future. However, these sources are usually deployed in way of “fit and forget” which to a great extent confines their value and presents challenges in relation to: Optimized DER operation related to time varying onsite dema...
A Conceptual Model to Optimize Operating Cost of Passenger Ships in Macau
Directory of Open Access Journals (Sweden)
Xin-long Xu
2015-01-01
Full Text Available To facilitate more convenient travel as the economy of Macau expands, the government of Macau has allowed shipping companies to add passenger ships and shipping lines. This paper demonstrates how shipping companies can reduce costs by optimizing passenger ships and crew size. It analyzes operating conditions for each shipping depot, including transit time, ships, and volume of passengers. A series of integer programming models is proposed. After a practical demonstration using Excel to solve the LP model, we show that the reduction in the number of passenger ships and crew size could reach 22.6% and 29.4%, respectively.
An Optimization Approach to Coexistence of Bluetooth and Wi-Fi Networks Operating in ISM Environment
Klajbor, Tomasz; Rak, Jacek; Wozniak, Jozef
Unlicensed ISM band is used by various wireless technologies. Therefore, issues related to ensuring the required efficiency and quality of operation of coexisting networks become essential. The paper addresses the problem of mutual interferences between IEEE 802.11b transmitters (commercially named Wi-Fi) and Bluetooth (BT) devices.An optimization approach to modeling the topology of BT scatternets is introduced, resulting in more efficient utilization of ISM environment consisting of BT and Wi-Fi networks. To achieve it, the Integer Linear Programming approach has been proposed. Example results presented in the paper illustrate significant benefits of using the proposed modeling strategy.
Optimal Operation of Plug-In Electric Vehicles in Power Systems with High Wind Power Penetrations
DEFF Research Database (Denmark)
Hu, Weihao; Su, Chi; Chen, Zhe
2013-01-01
The Danish power system has a large penetration of wind power. The wind fluctuation causes a high variation in the power generation, which must be balanced by other sources. The battery storage based Plug-In Electric Vehicles (PEV) may be a possible solution to balance the wind power variations...... in the power systems with high wind power penetrations. In this paper, the integration of plug-in electric vehicles in the power systems with high wind power penetrations is proposed and discussed. Optimal operation strategies of PEV in the spot market are proposed in order to decrease the energy cost for PEV...
Impact of Liquidity on Islamic Banks' Profitability: Evidence from Bangladesh
Directory of Open Access Journals (Sweden)
Limon Moinur Rasul
2013-04-01
Full Text Available This study examines the impact of liquidity on Islamic banks’ profitability during an 11 years period of 2001 to 2011. To explore and interpret the results the study has taken samples from five Islamic banks that have been in operation in Bangladesh on or before 2001 to till date. In order to construct the liquidity model it used four liquidity variables namely cash & due from banks to total assets (CDTA, cash & due from banks to total deposits (CDDEP, investment to total assets (INVSTA and investment to total deposits (INVSDEP. According to adjusted R squares profitability variables return on assets (ROA, return on equity (ROE and return on deposits (ROD are respectively 17.1%, 4.5% and 24.6% dependent on independent variables. The statistical results suggest that CDTA is found insignificant with all profitability variables, whereas CDDEP is individually significant with all profitability variables except ROE. On the other hand INVSTA and INVSDEP are recognized significant with all three profitability variables. However, when ROE stands for an insignificant relationship with the overall liquidity model, ROA and ROD are identified significantly correlated with the similar model at 1% significant level. Unsurprisingly the findings do strengthen the specification that the impact of liquidity reflects adequate imposition on profitability that the Islamic banks in Bangladesh must abide by.
Energy Technology Data Exchange (ETDEWEB)
Zhou, F. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Bohler, D. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Ding, Y. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Gilevich, S. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Huang, Z. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Loos, H. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Ratner, D. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Vetter, S. [SLAC National Accelerator Lab., Menlo Park, CA (United States)
2015-12-07
Photocathode RF gun has been widely used for generation of high-brightness electron beams for many different applications. We found that the drive laser distributions in such RF guns play important roles in minimizing the electron beam emittance. Characterizing the laser distributions with measurable parameters and optimizing beam emittance versus the laser distribution parameters in both spatial and temporal directions are highly desired for high-brightness electron beam operation. In this paper, we report systematic measurements and simulations of emittance dependence on the measurable parameters represented for spatial and temporal laser distributions at the photocathode RF gun systems of Linac Coherent Light Source. The tolerable parameter ranges for photocathode drive laser distributions in both directions are presented for ultra-low emittance beam operations.
Directory of Open Access Journals (Sweden)
Emran Tohidi
2013-01-01
Full Text Available The idea of approximation by monomials together with the collocation technique over a uniform mesh for solving state-space analysis and optimal control problems (OCPs has been proposed in this paper. After imposing the Pontryagins maximum principle to the main OCPs, the problems reduce to a linear or nonlinear boundary value problem. In the linear case we propose a monomial collocation matrix approach, while in the nonlinear case, the general collocation method has been applied. We also show the efficiency of the operational matrices of differentiation with respect to the operational matrices of integration in our numerical examples. These matrices of integration are related to the Bessel, Walsh, Triangular, Laguerre, and Hermite functions.
Optimizing relational algebra operations using discrimination-based joins and lazy products
DEFF Research Database (Denmark)
Henglein, Fritz
We show how to implement in-memory execution of the core re- lational algebra operations of projection, selection and cross-product eciently, using discrimination-based joins and lazy products. We introduce the notion of (partitioning) discriminator, which par- titions a list of values according...... to a specied equivalence relation on keys the values are associated with. We show how discriminators can be dened generically, purely functionally, and eciently (worst-case linear time) on top of the array-based basic multiset discrimination algorithm of Cai and Paige (1995). Discriminators provide the basis...... the selection operation to recognize on the y whenever it is applied to a cross-product, in which case it can choose an ecient discrimination-based equijoin implementation. The techniques subsume most of the optimization techniques based on relational algebra equalities, without need for a query preprocessing...
Optimizing relational algebra operations using discrimination-based joins and lazy products
DEFF Research Database (Denmark)
Henglein, Fritz
We show how to implement in-memory execution of the core re- lational algebra operations of projection, selection and cross-product eciently, using discrimination-based joins and lazy products. We introduce the notion of (partitioning) discriminator, which par- titions a list of values according...... to a specied equivalence relation on keys the values are associated with. We show how discriminators can be dened generically, purely functionally, and eciently (worst-case linear time) on top of the array-based basic multiset discrimination algorithm of Cai and Paige (1995). Discriminators provide the basis...... the selection operation to recognize on the y whenever it is applied to a cross-product, in which case it can choose an ecient discrimination-based equijoin implementation. The techniques subsume most of the optimization techniques based on relational algebra equalities, without need for a query preprocessing...
Methodology for optimizing the development and operation of gas storage fields
Energy Technology Data Exchange (ETDEWEB)
Mercer, J.C.; Ammer, J.R.; Mroz, T.H.
1995-04-01
The Morgantown Energy Technology Center is pursuing the development of a methodology that uses geologic modeling and reservoir simulation for optimizing the development and operation of gas storage fields. Several Cooperative Research and Development Agreements (CRADAs) will serve as the vehicle to implement this product. CRADAs have been signed with National Fuel Gas and Equitrans, Inc. A geologic model is currently being developed for the Equitrans CRADA. Results from the CRADA with National Fuel Gas are discussed here. The first phase of the CRADA, based on original well data, was completed last year and reported at the 1993 Natural Gas RD&D Contractors Review Meeting. Phase 2 analysis was completed based on additional core and geophysical well log data obtained during a deepening/relogging program conducted by the storage operator. Good matches, within 10 percent, of wellhead pressure were obtained using a numerical simulator to history match 2 1/2 injection withdrawal cycles.
Performance of Optimization Heuristics for the Operational Planning of Multi-energy Storage Systems
Haas, J.; Schradi, J.; Nowak, W.
2016-12-01
In the transition to low-carbon energy sources, energy storage systems (ESS) will play an increasingly important role. Particularly in the context of solar power challenges (variability, uncertainty), ESS can provide valuable services: energy shifting, ramping, robustness against forecast errors, frequency support, etc. However, these qualities are rarely modelled in the operational planning of power systems because of the involved computational burden, especially when multiple ESS technologies are involved. This work assesses two optimization heuristics for speeding up the optimal operation problem. It compares their accuracy (in terms of costs) and speed against a reference solution. The first heuristic (H1) is based on a merit order. Here, the ESS are sorted from lower to higher operational costs (including cycling costs). For each time step, the cheapest available ESS is used first, followed by the second one and so on, until matching the net load (demand minus available renewable generation). The second heuristic (H2) uses the Fourier transform to detect the main frequencies that compose the net load. A specific ESS is assigned to each frequency range, aiming to smoothen the net load. Finally, the reference solution is obtained with a mixed integer linear program (MILP). H1, H2 and MILP are subject to technical constraints (energy/power balance, ramping rates, on/off states...). Costs due to operation, replacement (cycling) and unserved energy are considered. Four typical days of a system with a high share of solar energy were used in several test cases, varying the resolution from one second to fifteen minutes. H1 and H2 achieve accuracies of about 90% and 95% in average, and speed-up times of two to three and one to two orders of magnitude, respectively. The use of the heuristics looks promising in the context of planning the expansion of power systems, especially when their loss of accuracy is outweighed by solar or wind forecast errors.
Profitability analysis of KINGLONG nearly 5 years
Zhang, Mei; Wen, Jinghua
2017-08-01
Profitability analysis for measuring business performance and forecast its prospects play an important role. In this paper, the research instance King Long Motor in understanding the basic theory on the basis of financial management, to take a combination of theory and data analysis methods, combined with a measure of profitability related indicators of King Long Motor company’s profitability do a specific analysis to identify factors constraining the profitability of Kinglong company exists and the motivation to improve profitability, which made recommendations to improve the profitability of Kinglong car company to promote the company’s future can be better and faster development.)
Taxation of Non-profit organization
BŘEHOVSKÝ, Miroslav
2007-01-01
Nowadays non-profit organizations are the integral parts of developed economics. They fill gap in the market, where exist market failures. Their main aim is not to reach profit but to offer services in which ``invisible hand of market{\\crqq} fail. But it doesn{\\crq}t mean, that they can{\\crq}t reach profit. Attention is on reasons why these non-profit organizations exist, potential profit or revenue are secondary aims. For these reasons there exist some differences in taxation of non-profit o...
A dynamic programming model for optimal planning of aquifer storage and recovery facility operations
Uddameri, V.
2007-01-01
Aquifer storage recovery (ASR) is an innovative technology with the potential to augment dwindling water resources in regions experiencing rapid growth and development. Planning and design of ASR systems requires quantifying how much water should be stored and appropriate times for storage and withdrawals within a planning period. A monthly scale planning model has been developed in this study to derive optimal (least cost) long-term policies for operating ASR systems and is solved using a recursive deterministic dynamic programming approach. The outputs of the model include annual costs of operation, the amount of water to be imported each month as well as the schedule for storage and extraction. A case study modeled after a proposed ASR system for Mustang Island and Padre Island service areas of the city of Corpus Christi is used to illustrate the utility of the developed model. The results indicate that for the assumed baseline demands, the ASR system is to be kept operational for a period of 4 months starting from May through August. Model sensitivity analysis indicated that increased seasonal shortages can be met using ASR with little additional costs. For the assumed cost structure, a 16% shortage increased the costs by 1.6%. However, the operation time of ASR increased from 4 to 8 months. The developed dynamic programming model is a useful tool to assess the feasibility of evaluating the use of ASR systems during regional-scale water resources planning endeavors.
Excited meson radiative transitions from lattice QCD using variationally optimized operators
Energy Technology Data Exchange (ETDEWEB)
Shultz, Christian J. [Old Dominion Univ., Norfolk, VA (United States); Dudek, Jozef J. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Old Dominion Univ., Norfolk, VA (United States); Edwards, Robert G. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
2015-06-02
We explore the use of 'optimized' operators, designed to interpolate only a single meson eigenstate, in three-point correlation functions with a vector-current insertion. These operators are constructed as linear combinations in a large basis of meson interpolating fields using a variational analysis of matrices of two-point correlation functions. After performing such a determination at both zero and non-zero momentum, we compute three-point functions and are able to study radiative transition matrix elements featuring excited state mesons. The required two- and three-point correlation functions are efficiently computed using the distillation framework in which there is a factorization between quark propagation and operator construction, allowing for a large number of meson operators of definite momentum to be considered. We illustrate the method with a calculation using anisotopic lattices having three flavors of dynamical quark all tuned to the physical strange quark mass, considering form-factors and transitions of pseudoscalar and vector meson excitations. In conclusion, the dependence on photon virtuality for a number of form-factors and transitions is extracted and some discussion of excited-state phenomenology is presented.
Is there an optimal resting velopharyngeal gap in operated cleft palate patients?
Directory of Open Access Journals (Sweden)
Rajesh Yellinedi
2013-01-01
Full Text Available Context: Videofluoroscopy in operated cleft palate patients. Aims: To determine the existence of an optimal resting velopharyngeal (VP gap in operated cleft palate patients Settings and Design: A retrospective analysis of lateral view videofluoroscopy of operated cleft palate patients. Materials and Methods: A total of 117 cases of operated cleft palate underwent videofluoroscopy between 2006 and 2011. The lateral view of videofluoroscopy was utilised in the study. A retrospective analysis of the lateral view of videofluoroscopy of these 117 patients was performed to analyse the resting VP gap and its relationship to VP closure. Statistical analysis used: None. Results: Of the 117 cases, 35 had a resting gap of less than 6 mm, 34 had a resting gap between 6 and 10 mm and 48 patients had a resting gap of more than 10 mm. Conclusions: The conclusive finding was that almost all the patients with a resting gap of 10 mm (group A did not achieve VP closure on phonation, thus having full-blown VPI. Therefore, it can be concluded that the ideal resting VP gap is approximately 6 mm so as to get the maximal chance of VP closure and thus prevent VPI.
Novotny, J; Jex, I
2006-01-01
The structure of all completely positive quantum operations is investigated which transform pure two-qubit input states of a given degree of entanglement in a covariant way. Special cases thereof are quantum NOT operations which transform entangled pure two-qubit input states of a given degree of entanglement into orthogonal states in an optimal way. Based on our general analysis all covariant optimal two-qubit quantum NOT operations are determined. In particular, it is demonstrated that only in the case of maximally entangled input states these quantum NOT operations can be performed perfectly.
Application of Discrete Event Simulation in LPG Storage Operation and Optimization
Directory of Open Access Journals (Sweden)
Jakub Dyntar
2012-05-01
Full Text Available In this paper, we present an application of discrete event simulation in Liquid Petroleum Gases (LPG storage operation and optimization. The proposed solution consists of Witness simulation model supported by MS Excel for data loading and outputs upgrading. The solution upgraded into the form of LPG Storage Simulator (LPG SIM adopts the principles of agent-based modeling and is suitable to support the decision making in LPG manufacturing, storing and distribution supply chain optimization. We apply our simulator to identify possible capacity constraints of LPG storage and expedition area owned by two operators (petrochemical company SYNTHOS Kralupy, a.s. and crude processing company ESK RAFINRSK, a.s. (CRC connected with planned intensification of LPG manufacturing. With help of LPG SIM we test 4 different varieties differing in the total amounts of products flowing from the CRC Fluid Catalytic Cracking unit to LPG storage and expedition area equipped with the rail way tank cars (RTC loading and road tank-trucks (RT loading terminal. For each simulated variety we specify the requirements on storage and expedition capacities ensuring the smooth product flows through the LPG storage area, gasoline blending requirements and the requirements on products expedition in RTC and RT.
Dynamic Feasible Region Genetic Algorithm for Optimal Operation of a Multi-Reservoir System
Directory of Open Access Journals (Sweden)
Bin Xu
2012-08-01
Full Text Available Seeking the optimal strategy of a multi-reservoir system is an important approach to develop hydropower energy, in which the Genetic Algorithm (GA is commonly used as an effective tool. However, when the traditional GA is applied in solving the problem, the constraints of water balance equation, hydraulic continuity relationship and power system load demand might be violated by the crossover and mutation operator, which decreases the efficiency of the algorithm in searching for a feasible region or even leads to a convergence on an infeasible chromosome within the expected generations. A modified GA taking stochastic operators within the feasible region of variables is proposed. When determining the feasible region of constraints, the progressive optimal approach is applied to transform constraints imposed on reservoirs into a singular-reservoir constraint, and a joint solution with consideration of adjacent periods at crossover or mutation points is used to turn the singular-reservoir constraints into singular variable constraints. Some statistic indexes are suggested to evaluate the performances of the algorithms. The experimental results show that compared to GA adopting a penalty function or pair-wise comparison in constraint handling, the proposed modified GA improves the refinement of the quality of a solution in a more efficient and robust way.
Assmann, Céline; Scott, Amanda; Biller, Dondra
2017-08-01
Organic measurements, such as biological oxygen demand (BOD) and chemical oxygen demand (COD) were developed decades ago in order to measure organics in water. Today, these time-consuming measurements are still used as parameters to check the water treatment quality; however, the time required to generate a result, ranging from hours to days, does not allow COD or BOD to be useful process control parameters - see (1) Standard Method 5210 B; 5-day BOD Test, 1997, and (2) ASTM D1252; COD Test, 2012. Online organic carbon monitoring allows for effective process control because results are generated every few minutes. Though it does not replace BOD or COD measurements still required for compliance reporting, it allows for smart, data-driven and rapid decision-making to improve process control and optimization or meet compliances. Thanks to the smart interpretation of generated data and the capability to now take real-time actions, municipal drinking water and wastewater treatment facility operators can positively impact their OPEX (operational expenditure) efficiencies and their capabilities to meet regulatory requirements. This paper describes how three municipal wastewater and drinking water plants gained process insights, and determined optimization opportunities thanks to the implementation of online total organic carbon (TOC) monitoring.
Robust optimal sensor placement for operational modal analysis based on maximum expected utility
Li, Binbin; Der Kiureghian, Armen
2016-06-01
Optimal sensor placement is essentially a decision problem under uncertainty. The maximum expected utility theory and a Bayesian linear model are used in this paper for robust sensor placement aimed at operational modal identification. To avoid nonlinear relations between modal parameters and measured responses, we choose to optimize the sensor locations relative to identifying modal responses. Since the modal responses contain all the information necessary to identify the modal parameters, the optimal sensor locations for modal response estimation provide at least a suboptimal solution for identification of modal parameters. First, a probabilistic model for sensor placement considering model uncertainty, load uncertainty and measurement error is proposed. The maximum expected utility theory is then applied with this model by considering utility functions based on three principles: quadratic loss, Shannon information, and K-L divergence. In addition, the prior covariance of modal responses under band-limited white-noise excitation is derived and the nearest Kronecker product approximation is employed to accelerate evaluation of the utility function. As demonstration and validation examples, sensor placements in a 16-degrees-of-freedom shear-type building and in Guangzhou TV Tower under ground motion and wind load are considered. Placements of individual displacement meter, velocimeter, accelerometer and placement of mixed sensors are illustrated.
Ibanez, Eduardo
Most U.S. energy usage is for electricity production and vehicle transportation, two interdependent infrastructures. The strength and number of the interdependencies will increase rapidly as hybrid electric transportation systems, including plug-in hybrid electric vehicles and hybrid electric trains, become more prominent. There are several new energy supply technologies reaching maturity, accelerated by public concern over global warming. The National Energy and Transportation Planning Tool (NETPLAN) is the implementation of the long-term investment and operation model for the transportation and energy networks. An evolutionary approach with underlying fast linear optimization are in place to determine the solutions with the best investment portfolios in terms of cost, resiliency and sustainability, i.e., the solutions that form the Pareto front. The popular NSGA-II algorithm is used as the base for the multiobjective optimization and metrics are developed for to evaluate the energy and transportation portfolios. An integrating approach to resiliency is presented, allowing the evaluation of high-consequence events, like hurricanes or widespread blackouts. A scheme to parallelize the multiobjective solver is presented, along with a decomposition method for the cost minimization program. The modular and data-driven design of the software is presented. The modeling tool is applied in a numerical example to optimize the national investment in energy and transportation in the next 40 years.
Institute of Scientific and Technical Information of China (English)
Ibrahim M.AL-HARKAN
2005-01-01
In this paper, a constrained genetic algorithm (CGA) is proposed to solve the single machine total weighted tardiness problem. The proposed CGA incorporates dominance rules for the problem under consideration into the GA operators. This incorporation should enable the proposed CGA to obtain close to optimal solutions with much less deviation and much less computational effort than the conventional GA (UGA). Several experiments were performed to compare the quality of solutions obtained by the three versions of both the CGA and the UGA with the results obtained by a dynamic programming approach. The computational results showed that the CGA was better than the UGA in both quality of solutions obtained and the CPU time needed to obtain the close to optimal solutions.The three versions of the CGA reduced the percentage deviation by 15.6%, 61.95%, and 25% respectively and obtained close to optimal solutions with 59% lower CPU time than what the three versions of the UGA demanded. The CGA performed better than the UGA in terms of quality of solutions and computational effort when the population size and the number of generations are smaller.
Directory of Open Access Journals (Sweden)
Yu Lu
2016-01-01
Full Text Available The main objective of this article is to describe an innovative methodology for the hydrodynamic optimization of a ship bulbous bow which considers multiple operating conditions. The proposed method is more practical and effective than the traditional optimization process, which is only based on contractually specified design condition. Parametric form approaches are adopted by employing an F-spline curve in order to generate variants of the hull bulbous bow forms using form design parameters modified, resulting in an optimization system based on improved genetic algorithms. The Rankine source panel method is used for the hydrodynamic evaluation, wherein non-linear free surface conditions and the trim and sinkage of the ship are taken into consideration. The validity and effectiveness of the proposed methodology for a large container ship is investigated by comparing the computational results with experimental data, which demonstrates that the proposed methodology can engage well in the automation process and improve hydrodynamic performance during actual ship design practices.
Intelligent decision support system of operation-optimization in copper smelting converter
Institute of Scientific and Technical Information of China (English)
姚俊峰; 梅炽; 彭小奇; 周安梁; 吴冬华
2002-01-01
An artificial intelligence technique was applied to the optimization of flux-adding systems and air-blasting systems, the display of on-line parameters, forecasting of mass and compositions of slag in the slagging period, optimization of cold material-adding systems and air-blasting systems, the display of on-line parameters, and the forecasting of copper mass in the copper blow period in copper smelting converters. They were integrated to build the Intelligent Decision Support System of the Operation-Optimization of Copper Smelting Converter(IDSSOOCSC), which is self-learning and self-adaptating. Development steps, monoblock structure and basic functions of the IDSSOOCSC were introduced. After it was applied in a copper smelting converter, every production quota was clearly improved after IDSSOOCSC had been run for 4 months. Blister copper productivity is increased by 6%, processing load of cold input is increased by 8% and average converter life-span is improved from 213 to 235 furnace times.
A Decomposition of Hospital Profitability
Directory of Open Access Journals (Sweden)
Jason Turner
2015-06-01
Full Text Available Objectives: This paper evaluates the drivers of profitability for a large sample of U.S. hospitals. Following a methodology frequently used by financial analysts, we use a DuPont analysis as a framework to evaluate the quality of earnings. By decomposing returns on equity (ROE into profit margin, total asset turnover, and capital structure, the DuPont analysis reveals what drives overall profitability. Methods: Profit margin, the efficiency with which services are rendered (total asset turnover, and capital structure is calculated for 3,255 U.S. hospitals between 2007 and 2012 using data from the Centers for Medicare & Medicaid Services’ Healthcare Cost Report Information System (CMS Form 2552. The sample is then stratified by ownership, size, system affiliation, teaching status, critical access designation, and urban or non-urban location. Those hospital characteristics and interaction terms are then regressed (OLS against the ROE and the respective DuPont components. Sensitivity to regression methodology is also investigated using a seemingly unrelated regression. Results: When the sample is stratified by hospital characteristics, the results indicate investor-owned hospitals have higher profit margins, higher efficiency, and are substantially more leveraged. Hospitals in systems are found to have higher ROE, margins, and efficiency but are associated with less leverage. In addition, a number of important and significant interactions between teaching status, ownership, location, critical access designation, and inclusion in a system are documented. Many of the significant relationships, most notably not-for-profit ownership, lose significance or are predominately associated with one interaction effect when interaction terms are introduced as explanatory variables. Results are not sensitive to the alternative methodology. Conclusion: The results of the DuPont analysis suggest that although there appears to be convergence in the behavior of
Improving Operability of Lab-Scale Spouted Bed Using Global Stochastic Optimization
Directory of Open Access Journals (Sweden)
Dr.Ghanim.M. Alwan
2015-01-01
Full Text Available A spouted bed is a special case of fluidization. It is an effective means of contacting gas with coarse solid particles .Gas-solid spouted beds are either cylindrical bed with cone base or the whole bed is in a cone shape where the gas enters as a jet. The gas forms a spout region that carries the solids upward in a diluted phase that forms a fountain at the top of the bed where the solids fall down and move downward in the annular region. Performance of gas-solid spouted bed benefit from solids uniformity structure with lower pressure drop (PD.Dropping of PD across a spouted bed could reduce the dissipated pumping energy and improve stability and uniformity of solid particles. The objective of this work is to study and selecting best operating conditions that could minimize PD across the bed. Optimization technique is a powerful tool would guide the experimental work and reduce the risk and cost for design and operation Hence, PD is to be considered as objective function of the optimization process .Three selected decision variables are affecting objective function. These decision variables are gas velocity, particle density and particle diameter. Steady-state measurements were carried out in a narrow 3-inch (0.076 m ID cylindrical spouted bed made of Plexiglas that used 60° conical shape base. Radial concentration of particles (glass and steel beads at various bed heights under different flow patterns were measured using sophisticated optical probes. A superficial velocity of air ranging from 0.74 to 1.0 m/s .PD was measured across the bed by high accuracy pressure transducers. Stochastic Genetic Algorithm (GA has found suitable global search for the non-linear hybrid spouted bed. Optimum results could select the best operating conditions for high-performance and stable conditions. Uniformity and stability of solid particles in the bed would enhance hydrodynamic parameters, heat and mass transfer. Best Operability of the bed was observed with
Energy Technology Data Exchange (ETDEWEB)
Ghatikar, Girish [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Greenlots, San Francisco, CA (United States); Mashayekh, Salman [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Stadler, Michael [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Center for Energy and Innovation Technologies (Austria); Yin, Rongxin [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Liu, Zhenhua [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
2015-11-29
Distributed power systems in the U.S. and globally are evolving to provide reliable and clean energy to consumers. In California, existing regulations require significant increases in renewable generation, as well as identification of customer-side distributed energy resources (DER) controls, communication technologies, and standards for interconnection with the electric grid systems. As DER deployment expands, customer-side DER control and optimization will be critical for system flexibility and demand response (DR) participation, which improves the economic viability of DER systems. Current DER systems integration and communication challenges include leveraging the existing DER and DR technology and systems infrastructure, and enabling optimized cost, energy and carbon choices for customers to deploy interoperable grid transactions and renewable energy systems at scale. Our paper presents a cost-effective solution to these challenges by exploring communication technologies and information models for DER system integration and interoperability. This system uses open standards and optimization models for resource planning based on dynamic-pricing notifications and autonomous operations within various domains of the smart grid energy system. It identifies architectures and customer engagement strategies in dynamic DR pricing transactions to generate feedback information models for load flexibility, load profiles, and participation schedules. The models are tested at a real site in California—Fort Hunter Liggett (FHL). Furthermore, our results for FHL show that the model fits within the existing and new DR business models and networked systems for transactive energy concepts. Integrated energy systems, communication networks, and modeling tools that coordinate supply-side networks and DER will enable electric grid system operators to use DER for grid transactions in an integrated system.
The Effects of Firm-Specific Factors on the Profitability of Non-Life Insurance Companies in Turkey
Directory of Open Access Journals (Sweden)
Emine Öner Kaya
2015-10-01
Full Text Available This study investigates the firm-specific factors affecting the profitability of non-life insurance companies operating in Turkey. For this purpose, data of 24 non-life insurance companies operating in Turkey from the period 2006–2013 were brought together to obtain 192 observed panel data sets. In this study, profitability is measured by two different variables: technical profitability ratio and sales profitability ratio. According to the empirical results, the firm-specific factors affecting the profitability of Turkish non-life insurance companies are the size of the company, age of the company, loss ratio, current ratio, and premium growth rate.
Institute of Scientific and Technical Information of China (English)
SIGFRIED OLG
2006-01-01
@@ At the end of the third quarter, the Chinese economy is growing,to put it mildly, at a rather fast pace. However, at this stage of development even fast growth comes at a price. For one, the environment is a big problem. Another big issue is employment.
Evidence-Based Recommendations for Optimizing Light in Day-to-Day Spaceflight Operations
Whitmire, Alexandra; Leveton, Lauren; Barger, Laura; Clark, Toni; Bollweg, Laura; Ohnesorge, Kristine; Brainard, George
2015-01-01
NASA Behavioral Health and Performance Element (BHP) personnel have previously reported on efforts to transition evidence-based recommendations for a flexible lighting system on the International Space Station (ISS). Based on these recommendations, beginning in 2016 the ISS will replace the current fluorescent-based lights with an LED-based system to optimize visual performance, facilitate circadian alignment, promote sleep, and hasten schedule shifting. Additional efforts related to lighting countermeasures in spaceflight operations have also been underway. As an example, a recent BHP research study led by investigators at Harvard Medical School and Brigham and Women's Hospital, evaluated the acceptability, feasibility, and effectiveness of blue-enriched light exposure during exercise breaks for flight controllers working the overnight shift in the Mission Control Center (MCC) at NASA Johnson Space Center. This effort, along with published laboratory studies that have demonstrated the effectiveness of appropriately timed light for promoting alertness, served as an impetus for new light options, and educational protocols for flight controllers. In addition, a separate set of guidelines related to the light emitted from electronic devices, were provided to the Astronaut Office this past year. These guidelines were based on an assessment led by NASA's Lighting Environment Test Facility that included measuring the spectral power distribution, irradiance, and radiance of light emitted from ISS-grade laptops and I-Pads, as well as Android devices. Evaluations were conducted with and without the use of off-the-shelf screen filters as well as a software application that touts minimizing the short-wave length of the visible light spectrum. This presentation will focus on the transition for operations process related to lighting countermeasures in the MCC, as well as the evidence to support recommendations for optimal use of laptops, I-Pads, and Android devices during all
Energy Technology Data Exchange (ETDEWEB)
Popa, R; Popa, B [Faculty of Power Engineering, University Politehnica of Bucharest, 313 Spl. Independentei, sect. 6, Bucharest, 060042 (Romania); Popa, F [Institute for Hydropower Studies and Design, 5-7 Vasile Lascar, sect. 2, Bucharest, 020491 (Romania); Zachia-Zlatea, D, E-mail: bogdan.popa@rosha.r [Hidroelectrica S.A., 3 Constantin Nacu, sect. 2, Bucharest, 020995 (Romania)
2010-08-15
It is presented an optimization model based on genetic algorithms for the operation of a multipurpose hydroelectric power development consisting in a pumped storage plant (PSP) with weekly operation cycle. The lower reservoir of the PSP is supplied upstream from a peak hydropower plant (HPP) with a large reservoir and supplies the own HPP which provides the required discharges towards downstream. Under these conditions, the optimum operation of the assembly consisting in 3 reservoirs and hydropower plants becomes a difficult problem if there are considered the restrictions as regards: the gradients allowed for the reservoirs filling/emptying, compliance with of a long-term policy of the upper reservoir from the hydroelectric development and of the weekly cycle for the PSP upper reservoir, correspondence between the power output/consumption in the weekly load schedule, turning to account of the water resource at maximum overall efficiencies, etc. Maximization of the net energy value (generated minus consumed) was selected as performance function of the model, considering the differentiated price of the electric energy over the week (working or weekend days, peak, half-peak or base hours). The analysis time step was required to be of 3 hours, resulting a weekly horizon of 56 steps and 168 decision variables, respectively, for the 3 HPPs of the system. These were allowed to be the flows turbined at the HPP and the number of working hydrounits at PSP, on each time step. The numerical application has considered the guiding data of Fantanele-Tarnita-Lapustesti hydroelectric development. Results of various simulations carried out proved the qualities of the proposed optimization model, which will allow its use within a decisional support program for such a development.
Popa, R.; Popa, F.; Popa, B.; Zachia-Zlatea, D.
2010-08-01
It is presented an optimization model based on genetic algorithms for the operation of a multipurpose hydroelectric power development consisting in a pumped storage plant (PSP) with weekly operation cycle. The lower reservoir of the PSP is supplied upstream from a peak hydropower plant (HPP) with a large reservoir and supplies the own HPP which provides the required discharges towards downstream. Under these conditions, the optimum operation of the assembly consisting in 3 reservoirs and hydropower plants becomes a difficult problem if there are considered the restrictions as regards: the gradients allowed for the reservoirs filling/emptying, compliance with of a long-term policy of the upper reservoir from the hydroelectric development and of the weekly cycle for the PSP upper reservoir, correspondence between the power output/consumption in the weekly load schedule, turning to account of the water resource at maximum overall efficiencies, etc. Maximization of the net energy value (generated minus consumed) was selected as performance function of the model, considering the differentiated price of the electric energy over the week (working or weekend days, peak, half-peak or base hours). The analysis time step was required to be of 3 hours, resulting a weekly horizon of 56 steps and 168 decision variables, respectively, for the 3 HPPs of the system. These were allowed to be the flows turbined at the HPP and the number of working hydrounits at PSP, on each time step. The numerical application has considered the guiding data of Fantanele-Tarnita-Lapustesti hydroelectric development. Results of various simulations carried out proved the qualities of the proposed optimization model, which will allow its use within a decisional support program for such a development.
Profiting from innovative user communities
DEFF Research Database (Denmark)
Jeppesen, Lars Bo
platforms. This article explains how manufacturers can profit from their abilities to organize and facilitate a process of innovation by user communities and capture the value of the innovations produced in such communities. When managed strategically, two distinct, but not mutually exclusive business......, a manufacturer can incorporate and commercialize the best complements found in the user communities. Keywords: innovation, modding, user communities, software platform, business model. JEL code(s): L21; L23; O31; O32...
Research on Optimal Operation by Adjusting Blade Angle in Jiangdu No. 4 Pumping Station of China
Lihua, Zhang; Jilin, Chang; Rentian, Zhang; Yi, Gong
2010-06-01
A Nonlinear Programming Model for the optimal day-operation of multi-units pump in one pumping station by adjusting blade angle has been put out, where the peak-valley electricity prices is considered in this paper. The model takes the minimal operation cost of pump assembly as objective function. In the meantime, the periods are defined as stage variables. The blade angle and the number of the working-pumps are expressed as decision variables and the water volume pumped in one day as constraint condition. The problem is very difficult to be settled by regular methods. This paper presents a new method which adopts experimental optimization method of adjusting blade angle in different periods and linear integral programming method to select the number of pumps. After applying the method to the optimal operation of Jiangdu No.4 pumping station, which is the source pump station of Eastern Route Project of South-to-North Water Diversion(Where there are seven pumps and the design flow rate of single-unit is 30.0m3/sec), we get the results which are as follows:(1) With the constraint conditions of typical tidal process which are average tidal levels from December to February of next year, designed average pumping head of 7.8m, and the operation load at 100%,80%,60% of full-load(the water volume when the pumps working with the blade angle of 0 degree and the speed of 150r/min in full day), the relative energy-saving reaches 5.18%˜33.02% comparing with the state of keeping the pump operating at its designed blade angle which is 0 degree when considering peak-valley electricity prices. While not considering the peak-valley electricity prices, the number is 1.96%˜9.71%, and less load corresponds to more cost-saving. (2) The key factory on deciding the operation state of pumps is electricity price when we consider the peak-valley electricity prices. All the pumps should be working and the blade angle should be in the largest state when at the valley price, while the number
Institute of Scientific and Technical Information of China (English)
Izabela NIELSEN; Robert WJCIK; Grzegorz BOCEWICZ; Zbigniew BANASZAK
2016-01-01
We present an extension of the resource-constrained multi-product scheduling problem for an automated guided vehicle (AGV) served flow shop, where multiple material handling transport modes provide movement of work pieces between machining centers in the multimodal transportation network (MTN). The multimodal processes behind the multi-product pro-duction flow executed in an MTN can be seen as processes realized by using various local periodically functioning processes. The considered network of repetitively acting local transportation modes encompassing MTN’s structure provides a framework for multimodal processes scheduling treated in terms of optimization of the AGVs fleet scheduling problem subject to fuzzy operation time constraints. In the considered case, both production takt and operation execution time are described by imprecise data. The aim of the paper is to present a constraint propagation (CP) driven approach to multi-robot task allocation providing a prompt service to a set of routine queries stated in both direct and reverse way. Illustrative examples taking into account an uncertain specification of robots and workers operation time are provided.
Customer profitability analysis in a particular firm
Turková, Karolína
2015-01-01
The bachelor thesis entitled "Customer profitability analysis in a particular firm" deals with approaches which are possible to use in an enterprise practice when analyzing customer profitability. The theoretical part describes tools and methods of management accounting which are used to analyze the profitability of customers. The application part consists of appraisal of the firm's current system of analyzing customer profitability and proposal of a new system. In the conclusion some recomme...
A constant elasticity of profit production function
Beard, Rodney
2007-01-01
Impact analysis of changes in production inputs may be simplified if one can apply a constant adjustment factor to profit. In particular, if a production function can be found for which the elasticity of profit is constant and this function has desirable properties, then one can use the input elasticity of profit to study the impact of input changes on profit. In this paper such a production function is derived from first principles.
Directory of Open Access Journals (Sweden)
Antonio Miguel Gil Salmerón
2016-10-01
Full Text Available Persistent financial crisis and the cases of corruption afflicting Spain have broken the trust of society that forcefully demands an ethical, responsible and sustainable management of organizations, which are not immune to environmental problems. The effects of globalization, the introduction of tecnoestructura as a management model, technological and socio-economic changes have reshaped the cultural, management and ownership system of the current company, the company nowadays is transferred the responsibility to combine growth and competitiveness with social development and environmental improvement. This reconfiguration of business management model is implemented with the introduction of Corporate Social Responsibility (CSR in the strategic plans of the companies with the purpose of achieving a competitive advantage. The question is: can the most responsible companies be more profitable? The introduction of CSR in the organizational culture of the companies involved as a vector, accelerates the profitability of the companies that apply it: the higher level of CSR used, the more profitable the companies are. These conclusions are determined from a linear regression analysis comparing the ROA –return on assets– to CSR levels in a hundred companies with higher levels of sustainability that operate in Spain, according to a survey published in 2014 by the Monitor business Corporate Reputation (Merco
Lender Profitability in the Student Loan Program.
Jenkins, Sarah
This report provides results of a study that measured lender profitability in the Guaranteed Student Loan (GSL) program and compares these results with the profitability of other types of lending. Data analysis reveals credit card lending to be the highest average level of profitability over the 5-year period considered. Other lending types, in…
RELATION OF DRILLING CAPACITY TO MARKET AND PROFIT
Directory of Open Access Journals (Sweden)
Mladen Zelenika
1994-12-01
Full Text Available Owner of drilling rigs should employ highly professional officers, who are capable to manage profit-orientated operations at all stages and make accurate analyses of the next three questions: how to deploy drilling crews to achieve the highest financial result; which kinds of equipment are compatible and employable in profitable operations, and how to compute the requirement of each type of equipment, and the number of drilling crews for a defined period and region to have profitable service. This paper introduce an original mathematical model convenient to compute exact values needed for an answer on these three questions. Application of this model is obvious for research of the relationship among: (i performance and cost of available drilling rigs, (ii condition on the market, and (iii estimated profit. Utilization of this model is possible only if records of market conditions' data, and data relating to progress and cost of operations in different conditions are established. These records will facilitate accurate estimation of input parameters' values and computation of output parameters' values using the Mathematical Model. Results of these computation should give basic data Tor precise plan of operation, rentabili-ty, and figures to decide the strategy of Drilling Company's capacity development.
Optimizing operational water management with soil moisture data from Sentinel-1 satellites
Pezij, Michiel; Augustijn, Denie; Hendriks, Dimmie; Hulscher, Suzanne
2016-04-01
In the Netherlands, regional water authorities are responsible for management and maintenance of regional water bodies. Due to socio-economic developments (e.g. agricultural intensification and on-going urbanisation) and an increase in climate variability, the pressure on these water bodies is growing. Optimization of water availability by taking into account the needs of different users, both in wet and dry periods, is crucial for sustainable developments. To support timely and well-directed operational water management, accurate information on the current state of the system as well as reliable models to evaluate water management optimization measures are essential. Previous studies showed that the use of remote sensing data (for example soil moisture data) in water management offers many opportunities (e.g. Wanders et al. (2014)). However, these data are not yet used in operational applications at a large scale. The Sentinel-1 satellites programme offers high spatiotemporal resolution soil moisture data (1 image per 6 days with a spatial resolution of 10 by 10 m) that are freely available. In this study, these data will be used to improve the Netherlands Hydrological Instrument (NHI). The NHI consists of coupled models for the unsaturated zone (MetaSWAP), groundwater (iMODFLOW) and surface water (Mozart and DM). The NHI is used for scenario analyses and operational water management in the Netherlands (De Lange et al., 2014). Due to the lack of soil moisture data, the unsaturated zone model is not yet thoroughly validated and its output is not used by regional water authorities for decision-making. Therefore, the newly acquired remotely sensed soil moisture data will be used to improve the skill of the MetaSWAP-model and the NHI as whole. The research will focus among other things on the calibration of soil parameters by comparing model output (MetaSWAP) with the remotely sensed soil moisture data. Eventually, we want to apply data-assimilation to improve
How to use Big Data technologies to optimize operations in Upstream Petroleum Industry
Directory of Open Access Journals (Sweden)
Abdelkader Baaziz
2013-12-01
Full Text Available “Big Data is the oil of the new economy” is the most famous citation during the three last years. It has even been adopted by the World Economic Forum in 2011. In fact, Big Data is like crude! It’s valuable, but if unrefined it cannot be used. It must be broken down, analyzed for it to have value. But what about Big Data generated by the Petroleum Industry and particularly its upstream segment? Upstream is no stranger to Big Data. Understanding and leveraging data in the upstream segment enables firms to remain competitive throughout planning, exploration, delineation, and field development.Oil & Gas Companies conduct advanced geophysics modeling and simulation to support operations where 2D, 3D & 4D Seismic generate significant data during exploration phases. They closely monitor the performance of their operational assets. To do this, they use tens of thousands of data-collecting sensors in subsurface wells and surface facilities to provide continuous and real-time monitoring of assets and environmental conditions. Unfortunately, this information comes in various and increasingly complex forms, making it a challenge to collect, interpret, and leverage the disparate data. As an example, Chevron’s internal IT traffic alone exceeds 1.5 terabytes a day.Big Data technologies integrate common and disparate data sets to deliver the right information at the appropriate time to the correct decision-maker. These capabilities help firms act on large volumes of data, transforming decision-making from reactive to proactive and optimizing all phases of exploration, development and production. Furthermore, Big Data offers multiple opportunities to ensure safer, more responsible operations. Another invaluable effect of that would be shared learning.The aim of this paper is to explain how to use Big Data technologies to optimize operations. How can Big Data help experts to decision-making leading the desired outcomes?Keywords:Big Data; Analytics
Vaudrey, A; Lanzetta, F; Glises, R
2009-01-01
Producing useful electrical work in consuming chemical energy, the fuel cell have to reject heat to its surrounding. However, as it occurs for any other type of engine, this thermal energy cannot be exchanged in an isothermal way in finite time through finite areas. As it was already done for various types of systems, we study the fuel cell within the finite time thermodynamics framework and define an endoreversible fuel cell. Considering different types of heat transfer laws, we obtain an optimal value of the operating temperature, corresponding to a maximum produced power. This analysis is a first step of a thermodynamical approach of design of thermal management devices, taking into account performances of the whole system.
Optimization of AGS Polarized Proton Operation with the Warm Helical Snake
Takano, Junpei; Bai, Mei; Brown, Kevin A; Gardner, Chris J; Glenn, Joseph; Hattori, Toshiyuki; Huang, Haixin; Luccio, Alfredo U; MacKay, William W; Okamura, Masahiro; Roser, Thomas; Tepikian, Steven; Tsoupas, Nicholaos
2005-01-01
A normal conducting helical dipole partial Siberian snake (Warm Snake) has been installed in the Alternating Gradient Synchrotron (AGS) at Brookhaven National Laboratory (BNL) for overcoming all of imperfection depolarizing resonances and reducing the transverse coupling resonances caused by the solenoidal Siberian snake which had been operated in AGS before the last polarized run. The polarized proton beam has been accelerated successfully with the warm snake and the polarization at extraction of the AGS was increased to 50% as opposed to 40% with the solenoidal snake. The magnetic field and beam trajectory in the warm snake was calculated by using the OPERA-3D/TOSCA software. We present optimization of the warm snake with beam during RUN5.
A note on Zolotarev optimal rational approximation for the overlap Dirac operator
Chiu, T W; Huang, C H; Huang, T R; Chiu, Ting-Wai; Hsieh, Tung-Han; Huang, Chao-Hsi; Huang, Tsung-Ren
2002-01-01
We discuss the salient features of Zolotarev optimal rational approximation for the inverse square root function, in particular, for its applications in lattice QCD with overlap Dirac quark. The theoretical error bound for the matrix-vector multiplication $ H_w (H_w^2)^{-1/2}Y $ is derived. We check that the error bound is always satisfied amply, for any QCD gauge configurations we have tested. An empirical formula for the error bound is determined, together with its numerical values (by evaluating elliptic functions) listed in Table 2 as well as plotted in Figure 3. Our results suggest that with Zolotarev approximation to $ (H_w^2)^{-1/2} $, one can practically preserve the exact chiral symmetry of the overlap Dirac operator to very high precision, for any gauge configurations on a finite lattice.
Optimization of the Operation of Green Buildings applying the Facility Management
Somorová, Viera
2014-06-01
Nowadays, in the field of civil engineering there exists an upward trend towards environmental sustainability. It relates mainly to the achievement of energy efficiency and also to the emission reduction throughout the whole life cycle of the building, i.e. in the course of its implementation, use and liquidation. These requirements are fulfilled, to a large extent, by green buildings. The characteristic feature of green buildings are primarily highly-sophisticated technical and technological equipments which are installed therein. The sophisticated systems of technological equipments need also the sophisticated management. From this point of view the facility management has all prerequisites to meet this requirement. The paper is aimed to define the facility management as an effective method which enables the optimization of the management of supporting activities by creating conditions for the optimum operation of green buildings viewed from the aspect of the environmental conditions
Reducing Wait Times through Operations Research: Optimizing the Use of Surge Capacity.
Patrick, Jonathan; Puterman, Martin L
2008-02-01
Widespread public demand for improved access, political pressure for shorter wait times, a stretched workforce, an aging population and overutilized equipment and facilities challenge healthcare leaders to adopt new management approaches. This paper highlights the significant benefits that can be achieved by applying operations research (OR) methods to healthcare management. It shows how queuing theory provides managers with insights into the causes for excessive wait times and the relationship between wait times and capacity. It provides a case study of the use of several OR methods, including Markov decision processes, linear programming and simulation, to optimize the scheduling of patients with multiple priorities. The study shows that by applying this approach, wait time targets can be attained with the judicious use of surge capacity in the form of overtime. It concludes with some policy insights.