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Sample records for scale decentralized model

  1. Event-triggered decentralized robust model predictive control for constrained large-scale interconnected systems

    Directory of Open Access Journals (Sweden)

    Ling Lu

    2016-12-01

    Full Text Available This paper considers the problem of event-triggered decentralized model predictive control (MPC for constrained large-scale linear systems subject to additive bounded disturbances. The constraint tightening method is utilized to formulate the MPC optimization problem. The local predictive control law for each subsystem is determined aperiodically by relevant triggering rule which allows a considerable reduction of the computational load. And then, the robust feasibility and closed-loop stability are proved and it is shown that every subsystem state will be driven into a robust invariant set. Finally, the effectiveness of the proposed approach is illustrated via numerical simulations.

  2. Decentralized State-Observer-Based Traffic Density Estimation of Large-Scale Urban Freeway Network by Dynamic Model

    Directory of Open Access Journals (Sweden)

    Yuqi Guo

    2017-08-01

    Full Text Available In order to estimate traffic densities in a large-scale urban freeway network in an accurate and timely fashion when traffic sensors do not cover the freeway network completely and thus only local measurement data can be utilized, this paper proposes a decentralized state observer approach based on a macroscopic traffic flow model. Firstly, by using the well-known cell transmission model (CTM, the urban freeway network is modeled in the way of distributed systems. Secondly, based on the model, a decentralized observer is designed. With the help of the Lyapunov function and S-procedure theory, the observer gains are computed by using linear matrix inequality (LMI technique. So, the traffic densities of the whole road network can be estimated by the designed observer. Finally, this method is applied to the outer ring of the Beijing’s second ring road and experimental results demonstrate the effectiveness and applicability of the proposed approach.

  3. Wind Farm Decentralized Dynamic Modeling With Parameters

    DEFF Research Database (Denmark)

    Soltani, Mohsen; Shakeri, Sayyed Mojtaba; Grunnet, Jacob Deleuran

    2010-01-01

    Development of dynamic wind flow models for wind farms is part of the research in European research FP7 project AEOLUS. The objective of this report is to provide decentralized dynamic wind flow models with parameters. The report presents a structure for decentralized flow models with inputs from...... local models. The results of this report are especially useful, but not limited, to design a decentralized wind farm controller, since in centralized controller design one can also use the model and update it in a central computing node.......Development of dynamic wind flow models for wind farms is part of the research in European research FP7 project AEOLUS. The objective of this report is to provide decentralized dynamic wind flow models with parameters. The report presents a structure for decentralized flow models with inputs from...

  4. Emergent Semantics Interoperability in Large-Scale Decentralized Information Systems

    CERN Document Server

    Cudré-Mauroux, Philippe

    2008-01-01

    Peer-to-peer systems are evolving with new information-system architectures, leading to the idea that the principles of decentralization and self-organization will offer new approaches in informatics, especially for systems that scale with the number of users or for which central authorities do not prevail. This book describes a new way of building global agreements (semantic interoperability) based only on decentralized, self-organizing interactions.

  5. Decentralized Large-Scale Power Balancing

    DEFF Research Database (Denmark)

    Halvgaard, Rasmus; Jørgensen, John Bagterp; Poulsen, Niels Kjølstad

    2013-01-01

    problem is formulated as a centralized large-scale optimization problem but is then decomposed into smaller subproblems that are solved locally by each unit connected to an aggregator. For large-scale systems the method is faster than solving the full problem and can be distributed to include an arbitrary...

  6. Iterative learning-based decentralized adaptive tracker for large-scale systems: a digital redesign approach.

    Science.gov (United States)

    Tsai, Jason Sheng-Hong; Du, Yan-Yi; Huang, Pei-Hsiang; Guo, Shu-Mei; Shieh, Leang-San; Chen, Yuhua

    2011-07-01

    In this paper, a digital redesign methodology of the iterative learning-based decentralized adaptive tracker is proposed to improve the dynamic performance of sampled-data linear large-scale control systems consisting of N interconnected multi-input multi-output subsystems, so that the system output will follow any trajectory which may not be presented by the analytic reference model initially. To overcome the interference of each sub-system and simplify the controller design, the proposed model reference decentralized adaptive control scheme constructs a decoupled well-designed reference model first. Then, according to the well-designed model, this paper develops a digital decentralized adaptive tracker based on the optimal analog control and prediction-based digital redesign technique for the sampled-data large-scale coupling system. In order to enhance the tracking performance of the digital tracker at specified sampling instants, we apply the iterative learning control (ILC) to train the control input via continual learning. As a result, the proposed iterative learning-based decentralized adaptive tracker not only has robust closed-loop decoupled property but also possesses good tracking performance at both transient and steady state. Besides, evolutionary programming is applied to search for a good learning gain to speed up the learning process of ILC. Copyright © 2011 ISA. Published by Elsevier Ltd. All rights reserved.

  7. Beyond the Diversity Crisis Model: Decentralized Diversity Planning and Implementation

    Science.gov (United States)

    Williams, Damon A.

    2008-01-01

    This article critiques the diversity crises model of diversity planning in higher education and presents a decentralized diversity planning model. The model is based on interviews with the nation's leading diversity officers, a review of the literature and the authors own experiences leading diversity change initiatives in higher education. The…

  8. Integrating Collaborative and Decentralized Models to Support Ubiquitous Learning

    Science.gov (United States)

    Barbosa, Jorge Luis Victória; Barbosa, Débora Nice Ferrari; Rigo, Sandro José; de Oliveira, Jezer Machado; Rabello, Solon Andrade, Jr.

    2014-01-01

    The application of ubiquitous technologies in the improvement of education strategies is called Ubiquitous Learning. This article proposes the integration between two models dedicated to support ubiquitous learning environments, called Global and CoolEdu. CoolEdu is a generic collaboration model for decentralized environments. Global is an…

  9. A microeconomic analysis of decentralized small scale biomass based CHP plants—The case of Germany

    International Nuclear Information System (INIS)

    Wittmann, Nadine; Yildiz, Özgür

    2013-01-01

    Alternative energy sources, such as biomass CHP plants, have recently gained significantly in importance and action is due both on the large scale corporate level and on the small scale. Hence, making the scope and economic outline of such projects easily intelligible without losing relevant details seems a key factor to further promote the necessary developments. The model setup presented in this paper may therefore serve as a starting point for generating numerical results based on real life cases or scenarios. Its focus lies on the economic analysis of decentralized biomass CHP plants. It presents a new approach to analyzing the economic aspects of biomass CHP plants implementing a formal microeconomic approach. As Germany claims a leading role in the market for renewable energy production, the paper also takes a closer look on the effects of German energy policy with respect to biomass CHP plants. - Highlights: • A formal microeconomic model is used to analyse a decentralized biomass CHP plant. • Model setup is used to generate numerical results based on real life scenarios. • Nested CES production function is a new approach to model economics of biomass CHP. • Analysis presents insight into microeconomics and cost drivers of biomass CHP. • Evaluation of energy policy design with respect to environmental policy goals

  10. A simulation model of a coordinated decentralized linear supply chain

    NARCIS (Netherlands)

    Ashayeri, Jalal; Cannella, S.; Lopez Campos, M.; Miranda, P.A.

    2015-01-01

    This paper presents a simulation-based study of a coordinated, decentralized linear supply chain (SC) system. In the proposed model, any supply tier considers its successors as part of its inventory system and generates replenishment orders on the basis of its partners’ operational information. We

  11. Model-Based Design of Tree WSNs for Decentralized Detection

    Directory of Open Access Journals (Sweden)

    Ashraf Tantawy

    2015-08-01

    Full Text Available The classical decentralized detection problem of finding the optimal decision rules at the sensor and fusion center, as well as variants that introduce physical channel impairments have been studied extensively in the literature. The deployment of WSNs in decentralized detection applications brings new challenges to the field. Protocols for different communication layers have to be co-designed to optimize the detection performance. In this paper, we consider the communication network design problem for a tree WSN. We pursue a system-level approach where a complete model for the system is developed that captures the interactions between different layers, as well as different sensor quality measures. For network optimization, we propose a hierarchical optimization algorithm that lends itself to the tree structure, requiring only local network information. The proposed design approach shows superior performance over several contentionless and contention-based network design approaches.

  12. Bi-Level Decentralized Active Power Control for Large-Scale Wind Farm Cluster

    DEFF Research Database (Denmark)

    Huang, Shengli; Wu, Qiuwei; Guo, Yifei

    2018-01-01

    This paper presents a bi-level decentralized active power control (DAPC) for a large-scale wind farm cluster, consisting of several wind farms for better active power dispatch. In the upper level, a distributed active power control scheme based on the distributed consensus is designed to achieve...... fair active power sharing among multiple wind farms, which generates the power reference for each wind farm. A distributed estimator is used to estimate the total available power of all wind farms. In the lower level, a centralized control scheme based on the Model Predictive Control (MPC) is proposed...... to regulate active power outputs of all wind turbines (WTs) within a wind farm, which reduces the fatigue loads of WTs while tracking the power reference obtained from the upper level control. A wind farm cluster with 8 wind farms and totally 160 WTs, was used to test the control performance of the proposed...

  13. A Decentralized Multivariable Robust Adaptive Voltage and Speed Regulator for Large-Scale Power Systems

    Science.gov (United States)

    Okou, Francis A.; Akhrif, Ouassima; Dessaint, Louis A.; Bouchard, Derrick

    2013-05-01

    This papter introduces a decentralized multivariable robust adaptive voltage and frequency regulator to ensure the stability of large-scale interconnnected generators. Interconnection parameters (i.e. load, line and transormer parameters) are assumed to be unknown. The proposed design approach requires the reformulation of conventiaonal power system models into a multivariable model with generator terminal voltages as state variables, and excitation and turbine valve inputs as control signals. This model, while suitable for the application of modern control methods, introduces problems with regards to current design techniques for large-scale systems. Interconnection terms, which are treated as perturbations, do not meet the common matching condition assumption. A new adaptive method for a certain class of large-scale systems is therefore introduces that does not require the matching condition. The proposed controller consists of nonlinear inputs that cancel some nonlinearities of the model. Auxiliary controls with linear and nonlinear components are used to stabilize the system. They compensate unknown parametes of the model by updating both the nonlinear component gains and excitation parameters. The adaptation algorithms involve the sigma-modification approach for auxiliary control gains, and the projection approach for excitation parameters to prevent estimation drift. The computation of the matrix-gain of the controller linear component requires the resolution of an algebraic Riccati equation and helps to solve the perturbation-mismatching problem. A realistic power system is used to assess the proposed controller performance. The results show that both stability and transient performance are considerably improved following a severe contingency.

  14. Decentralized Opportunistic Spectrum Resources Access Model and Algorithm toward Cooperative Ad-Hoc Networks

    Science.gov (United States)

    Liu, Ming; Xu, Yang; Mohammed, Abdul-Wahid

    2016-01-01

    Limited communication resources have gradually become a critical factor toward efficiency of decentralized large scale multi-agent coordination when both system scales up and tasks become more complex. In current researches, due to the agent’s limited communication and observational capability, an agent in a decentralized setting can only choose a part of channels to access, but cannot perceive or share global information. Each agent’s cooperative decision is based on the partial observation of the system state, and as such, uncertainty in the communication network is unavoidable. In this situation, it is a major challenge working out cooperative decision-making under uncertainty with only a partial observation of the environment. In this paper, we propose a decentralized approach that allows agents cooperatively search and independently choose channels. The key to our design is to build an up-to-date observation for each agent’s view so that a local decision model is achievable in a large scale team coordination. We simplify the Dec-POMDP model problem, and each agent can jointly work out its communication policy in order to improve its local decision utilities for the choice of communication resources. Finally, we discuss an implicate resource competition game, and show that, there exists an approximate resources access tradeoff balance between agents. Based on this discovery, the tradeoff between real-time decision-making and the efficiency of cooperation using these channels can be well improved. PMID:26727504

  15. Decentralized Opportunistic Spectrum Resources Access Model and Algorithm toward Cooperative Ad-Hoc Networks.

    Directory of Open Access Journals (Sweden)

    Ming Liu

    Full Text Available Limited communication resources have gradually become a critical factor toward efficiency of decentralized large scale multi-agent coordination when both system scales up and tasks become more complex. In current researches, due to the agent's limited communication and observational capability, an agent in a decentralized setting can only choose a part of channels to access, but cannot perceive or share global information. Each agent's cooperative decision is based on the partial observation of the system state, and as such, uncertainty in the communication network is unavoidable. In this situation, it is a major challenge working out cooperative decision-making under uncertainty with only a partial observation of the environment. In this paper, we propose a decentralized approach that allows agents cooperatively search and independently choose channels. The key to our design is to build an up-to-date observation for each agent's view so that a local decision model is achievable in a large scale team coordination. We simplify the Dec-POMDP model problem, and each agent can jointly work out its communication policy in order to improve its local decision utilities for the choice of communication resources. Finally, we discuss an implicate resource competition game, and show that, there exists an approximate resources access tradeoff balance between agents. Based on this discovery, the tradeoff between real-time decision-making and the efficiency of cooperation using these channels can be well improved.

  16. A Mixed Method Research for Finding a Model of Administrative Decentralization

    OpenAIRE

    Tahereh Feizy; Alireza Moghali; Masuod Geramipoor; Reza Zare

    2015-01-01

    One of the critical issues of administrative decentralization in translating theory into practice is understanding its meaning. An important method to identify administrative decentralization is to address how it can be planned and implemented, and what are its implications, and how it would overcome challenges. The purpose of this study is finding a model for analyzing and evaluating administrative decentralization, so a mixed method research was used to explore and confirm the model of Admi...

  17. Outdoor flocking of quadcopter drones with decentralized model predictive control.

    Science.gov (United States)

    Yuan, Quan; Zhan, Jingyuan; Li, Xiang

    2017-11-01

    In this paper, we present a multi-drone system featured with a decentralized model predictive control (DMPC) flocking algorithm. The drones gather localized information from neighbors and update their velocities using the DMPC flocking algorithm. In the multi-drone system, data packages are transmitted through XBee ® wireless modules in broadcast mode, yielding such an anonymous and decentralized system where all the calculations and controls are completed on an onboard minicomputer of each drone. Each drone is a double-layered agent system with the coordination layer running multi-drone flocking algorithms and the flight control layer navigating the drone, and the final formation of the flock relies on both the communication range and the desired inter-drone distance. We give both numerical simulations and field tests with a flock of five drones, showing that the DMPC flocking algorithm performs well on the presented multi-drone system in both the convergence rate and the ability of tracking a desired path. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  18. Fast Decentralized Averaging via Multi-scale Gossip

    Science.gov (United States)

    Tsianos, Konstantinos I.; Rabbat, Michael G.

    We are interested in the problem of computing the average consensus in a distributed fashion on random geometric graphs. We describe a new algorithm called Multi-scale Gossip which employs a hierarchical decomposition of the graph to partition the computation into tractable sub-problems. Using only pairwise messages of fixed size that travel at most O(n^{1/3}) hops, our algorithm is robust and has communication cost of O(n loglogn logɛ - 1) transmissions, which is order-optimal up to the logarithmic factor in n. Simulated experiments verify the good expected performance on graphs of many thousands of nodes.

  19. Integrating centralized and decentralized organization structures: an education and development model.

    Science.gov (United States)

    Sheriff, R; Banks, A

    2001-01-01

    Organization change efforts have led to critically examining the structure of education and development departments within hospitals. This qualitative study evaluated an education and development model in an academic health sciences center. The model combines centralization and decentralization. The study results can be used by staff development educators and administrators when organization structure is questioned. This particular model maximizes the benefits and minimizes the limitations of centralized and decentralized structures.

  20. Full-scale experimental validation of decentralized damage identification using wireless smart sensors

    International Nuclear Information System (INIS)

    Jang, Shinae; Sim, Sung-Han; Jo, Hongki; Spencer Jr, Billie F

    2012-01-01

    Wireless smart sensor networks (WSSN) facilitate a new paradigm for structural health monitoring (SHM) of civil infrastructure. Conventionally, SHM systems employing wired sensors and centralized data acquisition have been used to characterize the state of a structure; however, widespread implementation has been limited due to high costs and difficulties in installation. WSSN offer a unique opportunity to overcome such difficulties. Recent developments have realized low-cost, smart sensors with on-board computation and wireless communication capabilities, making deployment of a dense array of sensors on large civil structures both economical and feasible. Wireless smart sensors (WSS) have shown their tremendous potential for SHM in recent full-scale bridge monitoring examples. However, structural damage identification using on-board computation capability in a WSSN, a primary objective of SHM, has yet to reach its full potential. This paper presents full-scale validation of a damage identification strategy using a decentralized network of Imote2 nodes on a historic steel truss bridge. A total of 24 WSS nodes with 144 sensor channels are deployed on the bridge to validate the developed damage identification software. The performance of this decentralized damage identification strategy is demonstrated on the WSSN by comparing its results with those from the traditional centralized approach, as well as visual inspection. (paper)

  1. On Event-Triggered Adaptive Architectures for Decentralized and Distributed Control of Large-Scale Modular Systems.

    Science.gov (United States)

    Albattat, Ali; Gruenwald, Benjamin C; Yucelen, Tansel

    2016-08-16

    The last decade has witnessed an increased interest in physical systems controlled over wireless networks (networked control systems). These systems allow the computation of control signals via processors that are not attached to the physical systems, and the feedback loops are closed over wireless networks. The contribution of this paper is to design and analyze event-triggered decentralized and distributed adaptive control architectures for uncertain networked large-scale modular systems; that is, systems consist of physically-interconnected modules controlled over wireless networks. Specifically, the proposed adaptive architectures guarantee overall system stability while reducing wireless network utilization and achieving a given system performance in the presence of system uncertainties that can result from modeling and degraded modes of operation of the modules and their interconnections between each other. In addition to the theoretical findings including rigorous system stability and the boundedness analysis of the closed-loop dynamical system, as well as the characterization of the effect of user-defined event-triggering thresholds and the design parameters of the proposed adaptive architectures on the overall system performance, an illustrative numerical example is further provided to demonstrate the efficacy of the proposed decentralized and distributed control approaches.

  2. On Event-Triggered Adaptive Architectures for Decentralized and Distributed Control of Large-Scale Modular Systems

    Directory of Open Access Journals (Sweden)

    Ali Albattat

    2016-08-01

    Full Text Available The last decade has witnessed an increased interest in physical systems controlled over wireless networks (networked control systems. These systems allow the computation of control signals via processors that are not attached to the physical systems, and the feedback loops are closed over wireless networks. The contribution of this paper is to design and analyze event-triggered decentralized and distributed adaptive control architectures for uncertain networked large-scale modular systems; that is, systems consist of physically-interconnected modules controlled over wireless networks. Specifically, the proposed adaptive architectures guarantee overall system stability while reducing wireless network utilization and achieving a given system performance in the presence of system uncertainties that can result from modeling and degraded modes of operation of the modules and their interconnections between each other. In addition to the theoretical findings including rigorous system stability and the boundedness analysis of the closed-loop dynamical system, as well as the characterization of the effect of user-defined event-triggering thresholds and the design parameters of the proposed adaptive architectures on the overall system performance, an illustrative numerical example is further provided to demonstrate the efficacy of the proposed decentralized and distributed control approaches.

  3. A three-level atomicity model for decentralized workflow management systems

    Science.gov (United States)

    Ben-Shaul, Israel Z.; Heineman, George T.

    1996-12-01

    A workflow management system (WFMS) employs a workflow manager (WM) to execute and automate the various activities within a workflow. To protect the consistency of data, the WM encapsulates each activity with a transaction; a transaction manager (TM) then guarantees the atomicity of activities. Since workflows often group several activities together, the TM is responsible for guaranteeing the atomicity of these units. There are scalability issues, however, with centralized WFMSs. Decentralized WFMSs provide an architecture for multiple autonomous WFMSs to interoperate, thus accommodating multiple workflows and geographically-dispersed teams. When atomic units are composed of activities spread across multiple WFMSs, however, there is a conflict between global atomicity and local autonomy of each WFMS. This paper describes a decentralized atomicity model that enables workflow administrators to specify the scope of multi-site atomicity based upon the desired semantics of multi-site tasks in the decentralized WFMS. We describe an architecture that realizes our model and execution paradigm.

  4. A Decentralized Model for Coordinated Operation of Distribution Network and EV Aggregators

    DEFF Research Database (Denmark)

    Mohiti, Maryam; Mazidi, Mohammadreza; Monsef, Hassan

    2018-01-01

    With the rapid growth of electrical vehicles (EVs) in distribution networks (DNs), EV aggregators have been introduced as mediators between these two entities. EV aggregators and DN should be operated coordinately to bring potential benefits to both sides. In this paper, a decentralized model...

  5. Shifting Landscapes: The Impact of Centralized and Decentralized Nursing Station Models on the Efficiency of Care.

    Science.gov (United States)

    Fay, Lindsey; Carll-White, Allison; Schadler, Aric; Isaacs, Kathy B; Real, Kevin

    2017-10-01

    The focus of this research was to analyze the impact of decentralized and centralized hospital design layouts on the delivery of efficient care and the resultant level of caregiver satisfaction. An interdisciplinary team conducted a multiphased pre- and postoccupancy evaluation of a cardiovascular service line in an academic hospital that moved from a centralized to decentralized model. This study examined the impact of walkability, room usage, allocation of time, and visibility to better understand efficiency in the care environment. A mixed-methods data collection approach was utilized, which included pedometer measurements of staff walking distances, room usage data, time studies in patient rooms and nurses' stations, visibility counts, and staff questionnaires yielding qualitative and quantitative results. Overall, the data comparing the centralized and decentralized models yielded mixed results. This study's centralized design was rated significantly higher in its ability to support teamwork and efficient patient care with decreased staff walking distances. The decentralized unit design was found to positively influence proximity to patients in a larger design footprint and contribute to increased visits to and time spent in patient rooms. Among the factors contributing to caregiver efficiency and satisfaction are nursing station design, an integrated team approach, and the overall physical layout of the space on walkability, allocation of caregiver time, and visibility. However, unit design alone does not solely impact efficiency, suggesting that designers must consider the broader implications of a culture of care and processes.

  6. Autonomous Decentralized Enterprise Model - A New Wave in Web 2.0 Type E-commerce

    OpenAIRE

    Liu, Feng; Hirano, Makoto

    2010-01-01

    The rapid popularization of Web 2.0 coupled with the growth of e-commerce gives rise to enormous opportunities as well as changes for the creation of new intra-organization models. In the evolving environment of the E-business, this study has attempted to contribute to the framework description of a new type of inter-organizational model in e-commerce enterprises: Autonomous Decentralized Enterprise Model. From this case study,

  7. Application of Transfer Matrix Approach to Modeling and Decentralized Control of Lattice-Based Structures

    Science.gov (United States)

    Cramer, Nick; Swei, Sean Shan-Min; Cheung, Kenny; Teodorescu, Mircea

    2015-01-01

    This paper presents a modeling and control of aerostructure developed by lattice-based cellular materials/components. The proposed aerostructure concept leverages a building block strategy for lattice-based components which provide great adaptability to varying ight scenarios, the needs of which are essential for in- ight wing shaping control. A decentralized structural control design is proposed that utilizes discrete-time lumped mass transfer matrix method (DT-LM-TMM). The objective is to develop an e ective reduced order model through DT-LM-TMM that can be used to design a decentralized controller for the structural control of a wing. The proposed approach developed in this paper shows that, as far as the performance of overall structural system is concerned, the reduced order model can be as e ective as the full order model in designing an optimal stabilizing controller.

  8. Innovation, Decentralization, and Planning in a Multi-Region Model of Schumpeterian Economic Growth

    OpenAIRE

    Batabyal, Amit; Nijkamp, Peter

    2014-01-01

    We study innovation and the resulting Schumpeterian economic growth that this innovation gives rise to in a model with N heterogeneous regions. For each region i where i=1,...,N, our analysis leads to five findings. First, we define the balanced growth path (BGP) allocations and the equilibrium of interest. Second, we stipulate the form of the innovation possibilities frontier that is consistent with balanced economic growth. Third, we derive the growth rate of the ith region in the decentral...

  9. An Integrated Decentralized Energy Planning Model considering Demand-Side Management and Environmental Measures

    Directory of Open Access Journals (Sweden)

    Seyed Mahmood Kazemi

    2013-01-01

    Full Text Available Decentralized energy planning (DEP is looked upon as an indisputable opportunity for energy planning of villages, isolated islands, and far spots. Nonetheless, at this decentralized planning level, the value of demand-side resources is not fairly examined, despite enjoying great advantages. Therefore, the core task of this study is to integrate demand-side resources, as a competing solution against supply-side alternatives, with decentralized energy planning decisions and demonstrate the rewarding role it plays. Moreover, sustainability indicators (SIs are incorporated into DEP attempts in order to attain sustainable development. It is emphasized that unless these indicators are considered at lower energy planning levels, they will be ignored at higher planning levels as well. Hence, to the best knowledge of the authors, this study for the first time takes into account greenhouse gas (GHG emissions produced by utilization of renewable energies in DEP optimization models. To address the issues mentioned previously, multiobjective linear programming model along with a min-max goal programming approach is employed. Finally, using data taken from the literature, the model is solved, and the obtained results are discussed. The results show that DSM policies have remarkably contributed to significant improvements especially in terms of environmental indicators.

  10. Decentralization in Air Transportation

    NARCIS (Netherlands)

    Udluft, H.

    2017-01-01

    In this work,we demonstrate that decentralized control can result in stable, efficient, and robust operations in the Air Transportation System. We implement decentralized control for aircraft taxiing operations and use Agent-Based Modeling and Simulation to analyze the resulting system behavior

  11. Collective and decentralized management model in public hospitals: perspective of the nursing team.

    Science.gov (United States)

    Bernardes, Andrea; Cecilio, Luiz Carlos de Oliveira; Evora, Yolanda Dora Martinez; Gabriel, Carmen Silvia; Carvalho, Mariana Bernardes de

    2011-01-01

    This research aims to present the implementation of the collective and decentralized management model in functional units of a public hospital in the city of Ribeirão Preto, state of São Paulo, according to the view of the nursing staff and the health technical assistant. This historical and organizational case study used qualitative thematic content analysis proposed by Bardin for data analysis. The institution started the decentralization of its administrative structure in 1999, through collective management, which permitted several internal improvements, with positive repercussion for the care delivered to users. The top-down implementation of the process seems to have jeopardized workers adherence, although collective management has intensified communication and the sharing of power and decision. The study shows that there is still much work to be done to concretize this innovative management proposal, despite the advances regarding the quality of care.

  12. U-Form vs. M-Form: How to Understand Decision Autonomy Under Healthcare Decentralization?

    Science.gov (United States)

    Bustamante, Arturo Vargas

    2016-01-01

    For more than three decades healthcare decentralization has been promoted in developing countries as a way of improving the financing and delivery of public healthcare. Decision autonomy under healthcare decentralization would determine the role and scope of responsibility of local authorities. Jalal Mohammed, Nicola North, and Toni Ashton analyze decision autonomy within decentralized services in Fiji. They conclude that the narrow decision space allowed to local entities might have limited the benefits of decentralization on users and providers. To discuss the costs and benefits of healthcare decentralization this paper uses the U-form and M-form typology to further illustrate the role of decision autonomy under healthcare decentralization. This paper argues that when evaluating healthcare decentralization, it is important to determine whether the benefits from decentralization are greater than its costs. The U-form and M-form framework is proposed as a useful typology to evaluate different types of institutional arrangements under healthcare decentralization. Under this model, the more decentralized organizational form (M-form) is superior if the benefits from flexibility exceed the costs of duplication and the more centralized organizational form (U-form) is superior if the savings from economies of scale outweigh the costly decision-making process from the center to the regions. Budgetary and financial autonomy and effective mechanisms to maintain local governments accountable for their spending behavior are key decision autonomy variables that could sway the cost-benefit analysis of healthcare decentralization. PMID:27694684

  13. Decentralized portfolio management

    OpenAIRE

    Coutinho, Paulo; Tabak, Benjamin Miranda

    2003-01-01

    We use a mean-variance model to analyze the problem of decentralized portfolio management. We find the solution for the optimal portfolio allocation for a head trader operating in n different markets, which is called the optimal centralized portfolio. However, as there are many traders specialized in different markets, the solution to the problem of optimal decentralized allocation should be different from the centralized case. In this paper we derive conditions for the solutions to be equiva...

  14. Life-Cycle Cost and Environmental Assessment of Decentralized Nitrogen Recovery Using Ion Exchange from Source-Separated Urine through Spatial Modeling.

    Science.gov (United States)

    Kavvada, Olga; Tarpeh, William A; Horvath, Arpad; Nelson, Kara L

    2017-11-07

    Nitrogen standards for discharge of wastewater effluent into aquatic bodies are becoming more stringent, requiring some treatment plants to reduce effluent nitrogen concentrations. This study aimed to assess, from a life-cycle perspective, an innovative decentralized approach to nitrogen recovery: ion exchange of source-separated urine. We modeled an approach in which nitrogen from urine at individual buildings is sorbed onto resins, then transported by truck to regeneration and fertilizer production facilities. To provide insight into impacts from transportation, we enhanced the traditional economic and environmental assessment approach by combining spatial analysis, system-scale evaluation, and detailed last-mile logistics modeling using the city of San Francisco as an illustrative case study. The major contributor to energy intensity and greenhouse gas (GHG) emissions was the production of sulfuric acid to regenerate resins, rather than transportation. Energy and GHG emissions were not significantly sensitive to the number of regeneration facilities. Cost, however, increased with decentralization as rental costs per unit area are higher for smaller areas. The metrics assessed (unit energy, GHG emissions, and cost) were not significantly influenced by facility location in this high-density urban area. We determined that this decentralized approach has lower cost, unit energy, and GHG emissions than centralized nitrogen management via nitrification-denitrification if fertilizer production offsets are taken into account.

  15. Testing Metallic Iron Filtration Systems for Decentralized Water Treatment at Pilot Scale

    Directory of Open Access Journals (Sweden)

    Raoul Tepong-Tsindé

    2015-03-01

    Full Text Available There are many factors to consider for the design of appropriate water treatment systems including: cost, the concentration and type of biological and/or chemical contamination, concentration limits at which contaminant(s are required to be removed, required flow rate, level of local expertise for on-going maintenance, and social acceptance. An ideal technology should be effective at producing clean, potable water; however it must also be low-cost, low-energy (ideally energy-free and require low-maintenance. The use of packed beds containing metallic iron (Fe0 filters has the potential to become a cheap widespread technology for both safe drinking water provision and wastewater treatment. Fe0 filters have been intensively investigated over the past two decades, however, sound design criteria are still lacking. This article presents an overview of the design of Fe0 filters for decentralized water treatment particularly in the developing world. A design for safe drinking water to a community of 100 people is also discussed as starting module. It is suggested that Fe0 filters have the potential for significant worldwide applicability, but particularly in the developing world. The appropriate design of Fe0 filters, however, is site-specific and dependent upon the availability of local expertise/materials.

  16. Decentralized control of complex systems

    CERN Document Server

    Siljak, Dragoslav D

    2011-01-01

    Complex systems require fast control action in response to local input, and perturbations dictate the use of decentralized information and control structures. This much-cited reference book explores the approaches to synthesizing control laws under decentralized information structure constraints.Starting with a graph-theoretic framework for structural modeling of complex systems, the text presents results related to robust stabilization via decentralized state feedback. Subsequent chapters explore optimization, output feedback, the manipulative power of graphs, overlapping decompositions and t

  17. Decentralized control: An overview

    Czech Academy of Sciences Publication Activity Database

    Bakule, Lubomír

    2008-01-01

    Roč. 32, č. 1 (2008), s. 87-98 ISSN 1367-5788 R&D Projects: GA AV ČR(CZ) IAA200750802; GA MŠk(CZ) LA 282 Institutional research plan: CEZ:AV0Z10750506 Keywords : decentralized control * large-scale systems * decomposition Subject RIV: BC - Control Systems Theory Impact factor: 1.109, year: 2008

  18. Decentralized control and communication

    Czech Academy of Sciences Publication Activity Database

    Bakule, Lubomír; Papík, Martin

    2012-01-01

    Roč. 36, č. 1 (2012), s. 1-10 ISSN 1367-5788 R&D Projects: GA MŠk(CZ) LG12014 Institutional research plan: CEZ:AV0Z10750506 Keywords : decentralization * communication * large-scale complex systems Subject RIV: BC - Control Systems Theory Impact factor: 1.289, year: 2012

  19. TRUST MODEL FOR INFORMATION SECURITY OF MULTI-AGENT ROBOTIC SYSTEMS WITH A DECENTRALIZED MANAGEMENT

    Directory of Open Access Journals (Sweden)

    I. A. Zikratov

    2014-03-01

    Full Text Available The paper deals with the issues on protection of multi-agent robotic systems against attacks by robots-saboteurs. The operation analysis of such systems with decentralized control is carried out. Concept of harmful information impact (attack from a robot-saboteur to the multi-agent robotic system is given. The class of attacks is considered using interception of messages, formation and transfer of misinformation to group of robots, and also carrying out other actions with vulnerabilities of multiagent algorithms without obviously identified signs of invasion of robots-saboteurs. The model of information security is developed, in which robots-agents work out trust levels to each other analyzing the events occurring in the system. The idea of trust model consists in the analysis of transferred information by each robot and the executed actions of other members in a group, comparison of chosen decision on iteration step k with objective function of the group. Distinctive feature of the trust model in comparison with the closest analogue - Buddy Security Model in which the exchange between the agents security tokens is done — is involvement of the time factor during which agents have to "prove" by their actions the usefulness in achievement of a common goal to members of the group. Variants of this model realization and ways of an assessment of trust levels for agents in view of the security policy accepted in the group are proposed.

  20. Modeling Single-Phase Inverter and Its Decentralized Coordinated Control by Using Feedback Linearization

    Directory of Open Access Journals (Sweden)

    Renke Han

    2014-01-01

    Full Text Available It is a very crucial problem to make a microgrid operated reasonably and stably. Considering the nonlinear mathematics model of inverter established in this paper, the input-output feedback linearization method is used to transform the nonlinear mathematics model of inverters to a linear tracking synchronization and consensus regulation control problem. Based on the linear mathematics model and multiagent consensus algorithm, a decentralized coordinated controller is proposed to make amplitudes and angles of voltages from inverters be consensus and active and reactive power shared in the desired ratio. The proposed control is totally distributed because each inverter only requires local and one neighbor’s information with sparse communication structure based on multiagent system. The hybrid consensus algorithm is used to keep the amplitude of the output voltages following the leader and the angles of output voltage as consensus. Then the microgrid can be operated more efficiently and the circulating current between DGs can be effectively suppressed. The effectiveness of the proposed method is proved through simulation results of a typical microgrid system.

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

    International Nuclear Information System (INIS)

    Sarıca, Kemal; Kumbaroğlu, Gürkan; Or, Ilhan

    2012-01-01

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

  2. Decentralized Model Predictive Control for Cooperative Multiple Vehicles Subject to Communication Loss

    Directory of Open Access Journals (Sweden)

    Hojjat A. Izadi

    2011-01-01

    Full Text Available The decentralized model predictive control (DMPC of multiple cooperative vehicles with the possibility of communication loss/delay is investigated. The neighboring vehicles exchange their predicted trajectories at every sample time to maintain the cooperation objectives. In the event of a communication loss (packet dropout, the most recent available information, which is potentially delayed, is used. Then the communication loss problem changes to a cooperative problem when random large communication delays are present. Such large communication delays can lead to poor cooperation performance and unsafe behaviors such as collisions. A new DMPC approach is developed to improve the cooperation performance and achieve safety in the presence of the large communication delays. The proposed DMPC architecture estimates the tail of neighbor's trajectory which is not available due to the large communication delays for improving the performance. The concept of the tube MPC is also employed to provide the safety of the fleet against collisions, in the presence of large intervehicle communication delays. In this approach, a tube shaped trajectory set is assumed around the trajectory of the neighboring vehicles whose trajectory is delayed/lost. The radius of tube is a function of the communication delay and vehicle's maneuverability (in the absence of model uncertainty. The simulation of formation problem of multiple vehicles is employed to illustrate the effectiveness of the proposed approach.

  3. A Standardized, Evidence-Based Massage Therapy Program for Decentralized Elite Paracyclists: Creating the Model.

    Science.gov (United States)

    Kennedy, Ann B; Trilk, Jennifer L

    2015-09-01

    Evidence suggests that para-athletes are injured more often than able-bodied athletes. The benefits of massage therapy for these disabled athletes are yet to be explored. This paper documents the process followed for creating a massage program for elite paracycling athletes with the goal to assess effects on recovery, rest, performance, and quality of life both on and off the bike. Massage therapists' private practices throughout the United States. A United States Paracycling team consisting of 9 elite athletes: 2 spinal cord injury, 2 lower limb amputation, 1 upper limb amputation, 1 transverse myelitis, 1 stroke, 1 traumatic brain injury, and 1 visually impaired. The process used to develop a massage therapy program for para-cyclists included meetings with athletes, coaching staff, team exercise physiologist, and sports massage therapists; peer-reviewed literature was also consulted to address specific health conditions of para-athletes. Team leadership and athletes identified needs for quicker recovery, better rest, and improved performance in elite paracyclists. This information was used to generate a conceptual model for massage protocols, and led to creation of the intake and exit questionnaires to assess patient health status and recovery. Forms also were created for a general health intake, therapist information, and a therapist's SOAAP notes. The conceptual model and questionnaires developed herein will help to operationalize an exploratory study investigating the feasibility of implementing a standardized massage therapy program for a decentralized elite paracycling team.

  4. TRUST AND REPUTATION MODEL DESIGN FOR OBJECTS OF MULTI-AGENT ROBOTICS SYSTEMS WITH DECENTRALIZED CONTROL

    Directory of Open Access Journals (Sweden)

    I. A. Zikratov

    2014-03-01

    Full Text Available The problem of mechanisms design for protection of multi-agent robotics systems from attacks of robots-saboteurs is considered. Functioning analysis of these systems with decentralized control is carried out. The type of the so-called soft attacks using interception of messages, misinformation formation and transmission to group of robots which are also realizing other actions without identified signs of invasion of robots-saboteurs. Analysis of existing information security models of the system based on the trust level computation, calculated in the process of agents’ interaction is carried out. Information security model is offered in which robots-agents produce the trust levels to each other on the basis of situation analysis emerging on a certain step of iterative algorithm with usage of onboard sensor devices. On the basis of calculated trust levels, recognition of “saboteur” objects in the group of legitimate robots-agents is done. For measure of likeness (adjacency increase for objects from the same category (“saboteur” or “legitimate agent”, calculation algorithm for agents reputation is offered as a measure of public opinion about qualities of this or that agent-subject. Implementation alternatives of the algorithms for detection of saboteurs on the example of the basic algorithm for distribution of purposes in the group of robots are considered.

  5. Compositional data supports decentralized model of production and circulation of artifacts in the pre-Columbian south-central Andes.

    Science.gov (United States)

    Lazzari, Marisa; Pereyra Domingorena, Lucas; Stoner, Wesley D; Scattolin, María Cristina; Korstanje, María Alejandra; Glascock, Michael D

    2017-05-16

    The circulation and exchange of goods and resources at various scales have long been considered central to the understanding of complex societies, and the Andes have provided a fertile ground for investigating this process. However, long-standing archaeological emphasis on typological analysis, although helpful to hypothesize the direction of contacts, has left important aspects of ancient exchange open to speculation. To improve understanding of ancient exchange practices and their potential role in structuring alliances, we examine material exchanges in northwest Argentina (part of the south-central Andes) during 400 BC to AD 1000 (part of the regional Formative Period), with a multianalytical approach (petrography, instrumental neutron activation analysis, laser ablation inductively coupled plasma mass spectrometry) to artifacts previously studied separately. We assess the standard centralized model of interaction vs. a decentralized model through the largest provenance database available to date in the region. The results show: ( i ) intervalley heterogeneity of clays and fabrics for ordinary wares; ( ii ) intervalley homogeneity of clays and fabrics for a wide range of decorated wares (e.g., painted Ciénaga); ( iii ) selective circulation of two distinct polychrome wares (Vaquerías and Condorhuasi); ( iv ) generalized access to obsidian from one major source and various minor sources; and ( v ) selective circulation of volcanic rock tools from a single source. These trends reflect the multiple and conflicting demands experienced by people in small-scale societies, which may be difficult to capitalize by aspiring elites. The study undermines centralized narratives of exchange for this period, offering a new platform for understanding ancient exchange based on actual material transfers, both in the Andes and beyond.

  6. Decentralized electrification by small-scale hydraulic stations : a viable solution in mountainous regions

    International Nuclear Information System (INIS)

    Dahman Saidi, A.

    1998-01-01

    The installation of a small-scale hydroelectric generating station to supply electricity to the small community of Takordmi in Morocco was described. The community of Takordmi consists of 32 households located in the remote mountainous region of Morocco. Takordmi was without electrical power until 1992 when a small 15 kW Pelton turbine was installed to supply electricity to the residents. Water to power the turbine generator was supplied by a small stream with an output of 4 to 8 liters per second and a head of 535 meters. Since the unit was installed, the mean monthly consumption of the community has been only 115 kWh, which averages to 4 kWh per household. The success of the Takordmi project has prompted the electrification of several other small communities in the remote regions of Morocco either by similar micro-hydroelectric stations or by photovoltaic cells. This project, funded by the Republic of Austria, demonstrates that it is feasible to provide electricity to remote rural communities by using local sources of power. 3 figs

  7. The Two Edge Knife of Decentralization

    Directory of Open Access Journals (Sweden)

    Ahmad Khoirul Umam

    2011-07-01

    Full Text Available A centralistic government model has become a trend in a number of developing countries, in which the ideosycretic aspect becomes pivotal key in the policy making. The situation constitutes authoritarianism, cronyism, and corruption. To break the impasse, the decentralized system is proposed to make people closer to the public policy making. Decentralization is also convinced to be the solution to create a good governance. But a number of facts in the developing countries demonstrates that decentralization indeed has ignite emerges backfires such as decentralized corruption, parochialism, horizontal conflict, local political instability and others. This article elaborates the theoretical framework on decentralization's ouput as the a double-edge knife. In a simple words, the concept of decentralization does not have a permanent relationship with the creation of good governance and development. Without substantive democracy, decentralization is indeed potential to be a destructive political instrument threating the state's future.

  8. U-Form vs. M-Form: How to Understand Decision Autonomy Under Healthcare Decentralization? Comment on "Decentralisation of Health Services in Fiji: A Decision Space Analysis".

    Science.gov (United States)

    Bustamante, Arturo Vargas

    2016-06-07

    For more than three decades healthcare decentralization has been promoted in developing countries as a way of improving the financing and delivery of public healthcare. Decision autonomy under healthcare decentralization would determine the role and scope of responsibility of local authorities. Jalal Mohammed, Nicola North, and Toni Ashton analyze decision autonomy within decentralized services in Fiji. They conclude that the narrow decision space allowed to local entities might have limited the benefits of decentralization on users and providers. To discuss the costs and benefits of healthcare decentralization this paper uses the U-form and M-form typology to further illustrate the role of decision autonomy under healthcare decentralization. This paper argues that when evaluating healthcare decentralization, it is important to determine whether the benefits from decentralization are greater than its costs. The U-form and M-form framework is proposed as a useful typology to evaluate different types of institutional arrangements under healthcare decentralization. Under this model, the more decentralized organizational form (M-form) is superior if the benefits from flexibility exceed the costs of duplication and the more centralized organizational form (U-form) is superior if the savings from economies of scale outweigh the costly decision-making process from the center to the regions. Budgetary and financial autonomy and effective mechanisms to maintain local governments accountable for their spending behavior are key decision autonomy variables that could sway the cost-benefit analysis of healthcare decentralization. © 2016 by Kerman University of Medical Sciences.

  9. Decentralized control of large-scale systems: Fixed modes, sensitivity and parametric robustness. Ph.D. Thesis - Universite Paul Sabatier, 1985

    Science.gov (United States)

    Tarras, A.

    1987-01-01

    The problem of stabilization/pole placement under structural constraints of large scale linear systems is discussed. The existence of a solution to this problem is expressed in terms of fixed modes. The aim is to provide a bibliographic survey of the available results concerning the fixed modes (characterization, elimination, control structure selection to avoid them, control design in their absence) and to present the author's contribution to this problem which can be summarized by the use of the mode sensitivity concept to detect or to avoid them, the use of vibrational control to stabilize them, and the addition of parametric robustness considerations to design an optimal decentralized robust control.

  10. Field-scale electrolysis/ceramic membrane system for the treatment of sewage from decentralized small communities.

    Science.gov (United States)

    Son, Dong-Jin; Kim, Woo-Yeol; Yun, Chan-Young; Kim, Dae-Gun; Chang, Duk; Sunwoo, Young; Hong, Ki-Ho

    2017-07-05

    The electrolysis process adopting copper electrodes and ceramic membrane with pore sizes of 0.1-0.2 μm were consisted to a system for the treatment of sewage from decentralized small communities. The system was operated under an HRT of 0.1 hour, voltage of 24 V, and TMP of 0.05 MPa. The system showed average removals of organics, nitrogen, phosphorus, and solids of up to 80%, 52%, 92%, and 100%, respectively. Removal of organics and nitrogen dramatically increased in proportion to increment of influent loading. Phosphorus and solids were remarkably eliminated by both electro-coagulation and membrane filtration. The residual particulate constituents could also be removed successfully through membrane process. A system composed of electrolysis process with ceramic membrane would be a compact, reliable, and flexible option for the treatment of sewage from decentralized small communities.

  11. Models for transient simulations of decentral power generation - implementation and verification in PowerFactory

    OpenAIRE

    Braun, M.

    2005-01-01

    As part of the Institut für Solare Energieversorgungstechnik (ISET) e.V. in Kassel, the Design Center for Modular Supply Technology (DeMoTec) has the facilities for testing a variety of low-voltage power grid configurations. These configurations consist of decentralized power generation components in the kilowatt range. Transient simulations of components and grid configurations with MATLAB/Simulink, ATP-EMTP and SIMPLORER support research activities in this field. The aim of this work is to...

  12. Decentralized Bribery and Market Participation

    OpenAIRE

    Popov, Sergey V.

    2012-01-01

    I propose a bribery model that examines decentralized bureaucratic decision-making. There are multiple stable equilibria. High levels of bribery reduce an economy's productivity because corruption suppresses small business, and reduces the total graft, even though the size of an individual bribe might increase. Decentralization prevents movement towards a Pareto-dominant equilibrium. Anticorruption efforts, even temporary ones, might be useful to improve participation, if they lower the bribe...

  13. Decentralized Portfolio Management

    Directory of Open Access Journals (Sweden)

    Benjamin Miranda Tabak

    2003-12-01

    Full Text Available We use a mean-variance model to analyze the problem of decentralized portfolio management. We find the solution for the optimal portfolio allocation for a head trader operating in n different markets, which is called the optimal centralized portfolio. However, as there are many traders specialized in different markets, the solution to the problem of optimal decentralized allocation should be different from the centralized case. In this paper we derive conditions for the solutions to be equivalent. We use multivariate normal returns and a negative exponential function to solve the problem analytically. We generate the equivalence of solutions by assuming that different traders face different interest rates for borrowing and lending. This interest rate is dependent on the ratio of the degrees of risk aversion of the trader and the head trader, on the excess return, and on the correlation between asset returns.

  14. Decentralized Ground Staff Scheduling

    DEFF Research Database (Denmark)

    Sørensen, M. D.; Clausen, Jens

    2002-01-01

    scheduling is investigated. The airport terminal is divided into zones, where each zone consists of a set of stands geographically next to each other. Staff is assigned to work in only one zone and the staff scheduling is planned decentralized for each zone. The advantage of this approach is that the staff...... work in a smaller area of the terminal and thus spends less time walking between stands. When planning decentralized the allocation of stands to flights influences the staff scheduling since the workload in a zone depends on which flights are allocated to stands in the zone. Hence solving the problem...... depends on the actual stand allocation but also on the number of zones and the layout of these. A mathematical model of the problem is proposed, which integrates the stand allocation and the staff scheduling. A heuristic solution method is developed and applied on a real case from British Airways, London...

  15. A two-level discount model for coordinating a decentralized supply chain considering stochastic price-sensitive demand

    Science.gov (United States)

    Heydari, Jafar; Norouzinasab, Yousef

    2015-12-01

    In this paper, a discount model is proposed to coordinate pricing and ordering decisions in a two-echelon supply chain (SC). Demand is stochastic and price sensitive while lead times are fixed. Decentralized decision making where downstream decides on selling price and order size is investigated. Then, joint pricing and ordering decisions are extracted where both members act as a single entity aim to maximize whole SC profit. Finally, a coordination mechanism based on quantity discount is proposed to coordinate both pricing and ordering decisions simultaneously. The proposed two-level discount policy can be characterized from two aspects: (1) marketing viewpoint: a retail price discount to increase the demand, and (2) operations management viewpoint: a wholesale price discount to induce the retailer to adjust its order quantity and selling price jointly. Results of numerical experiments demonstrate that the proposed policy is suitable to coordinate SC and improve the profitability of SC as well as all SC members in comparison with decentralized decision making.

  16. Satisfaction and sustainability: a realist review of decentralized models of perinatal surgery for rural women.

    Science.gov (United States)

    Kornelsen, Jude; McCartney, Kevin; Williams, Kim

    2016-01-01

    This article was developed as part of a larger realist review investigating the viability and efficacy of decentralized models of perinatal surgical services for rural women in the context of recent and ongoing service centralization witnessed in many developed nations. The larger realist review was commissioned by the British Columbia Ministry of Health and Perinatal Services of British Columbia, Canada. Findings from that review are addressed in this article specific to the sustainability of rural perinatal surgical sites and the satisfaction of providers that underpins their recruitment to and retention at such sites. A realist method was used in the selection and analysis of literature with the intention to iteratively develop a sophisticated understanding of how perinatal surgical services can best meet the needs of women who live in rural and remote environments. The goal of a realist review is to examine what works for whom under what circumstances and why. The high sensitivity search used language (English) and year (since 1990) limiters in keeping with both a realist and rapid review tradition of using reasoned contextual boundaries. No exclusions were made based on methodology or methodological approach in keeping with a realist review. Databases searched included MEDLINE, PubMed, EBSCO, CINAHL, EBM Reviews, NHS Economic Evaluation Database and PAIS International for literature in December 2013. Database searching produced 103 included academic articles. A further 59 resources were added through pearling and 13 grey literature reports were added on recommendation from the commissioner. A total of 42 of these 175 articles were included in this article as specific to provider satisfaction and service sustainability. Operative perinatal practice was found to be a lynchpin of sustainable primary and surgical services in rural communities. Rural shortages of providers, including challenges with recruitment and retention, were found to be a complex issue, with

  17. COINSTAC: Decentralizing the future of brain imaging analysis [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Jing Ming

    2017-08-01

    Full Text Available In the era of Big Data, sharing neuroimaging data across multiple sites has become increasingly important. However, researchers who want to engage in centralized, large-scale data sharing and analysis must often contend with problems such as high database cost, long data transfer time, extensive manual effort, and privacy issues for sensitive data. To remove these barriers to enable easier data sharing and analysis, we introduced a new, decentralized, privacy-enabled infrastructure model for brain imaging data called COINSTAC in 2016. We have continued development of COINSTAC since this model was first introduced. One of the challenges with such a model is adapting the required algorithms to function within a decentralized framework. In this paper, we report on how we are solving this problem, along with our progress on several fronts, including additional decentralized algorithms implementation, user interface enhancement, decentralized regression statistic calculation, and complete pipeline specifications.

  18. Promoting collaboration and cultural competence for physician assistant and physical therapist students: a cross-cultural decentralized interprofessional education model

    Directory of Open Access Journals (Sweden)

    Kathleen De Oliveira

    2015-05-01

    Full Text Available Purpose: As the United States health care model progresses towards medical teams and the country’s population continues to diversify, the need for health professional education programs to develop and implement culturally specific interprofessional education (IPE becomes increasingly imperative. A wide range of models exists for delivering and implementing IPE in health education, but none have included the cultural components that are vital in educating the health professional. Methods: A cross-cultural decentralized IPE model for physician assistant (PA and physical therapy (PT students was developed. This three-part IPE series was created using an established cultural curricular model and began with the exploration of self, continued with the examination of various dimensions of culture, and concluded with the exploration of the intersection between health and culture. We assessed student satisfaction of the IPE experiences and students’ engagement and attitudes towards IPE using a three-item open-ended questionnaire administered after each cross-cultural activity and the Interprofessional Education Series Survey (IESS upon the completion of the series. Results: IESS responses showed that PA and PT students reported benefits in interprofessional collaboration and cultural awareness and expressed overall satisfaction with the series. Qualitative analysis revealed growth in student response depth consistent with the scaffolded focus of each IPE module in the series. Conclusion: The trends in this three-part series suggest that institutions looking to develop culturally inclusive IPE educational initiatives may have success through a decentralized model mirroring the effective cultural progression focused on addressing exploration of self, examination of various dimensions of culture, and exploration of the intersection between health and culture.

  19. Decentralized model for distributed storage system%去中心化的分布式存储模型

    Institute of Scientific and Technical Information of China (English)

    郝琨; 信俊昌; 黄达; 王国仁

    2017-01-01

    In the distributed storage systems, the metadata stored on the central node, which is prone to a single point of failure and is easily modified by malicious ones. Although the problem can be avoided to some extent by using backup nodes, the synchronization and handover between the nodes are less efficient. At the same time, nodes that store metadata can agree on modifying metadata, which is lacking credibility. For the problems of distributed storage system, a decentral-ized data storage model is proposed, namely DMB(Decentralized Metadata Blockchain), which combines with the charac-teristics of blockchain. The DMB model guarantees metadata integrity by saving metadata in blocks, redundant storage for blockchain, and collaboration validation. The model is divided into two phases which are storage phase and verifica-tion phase. In the storage phase, the model sends the user's signature and locations of data to verification nodes, and uses the signature and data locations to generate metadata block. In the verification phase, the verification nodes check whether the local and global states of the metadata block chain are the same. If they are not the same, the DMB model performs the synchronization of the state, and then the verification nodes retrieve local the metadata blockchain to verify the integrity of metadata. The theoretical and experimental results show that the DMB model can guarantee the retrievability and possession of the metadata, and has better concurrent processing ability, which has little effect on the efficiency of the data stored.%分布式数据存储过程中的元数据保存在中心节点上,容易造成单点故障和易被恶意修改,安全性较差.虽然,通过引入备份节点可以一定程度上避免该问题,但节点之间的同步和切换效率较低.同时,存储元数据的节点可以达成共识修改元数据,缺乏可信性.针对传统分布式存储中存在的问题,结合区块链的特点,提出一种去中心化的分布式存储模型DMB(Decentralized

  20. U-Form vs. M-Form: How to Understand Decision Autonomy Under Healthcare Decentralization?; Comment on “Decentralisation of Health Services in Fiji: A Decision Space Analysis”

    Directory of Open Access Journals (Sweden)

    Arturo Vargas Bustamante

    2016-09-01

    Full Text Available For more than three decades healthcare decentralization has been promoted in developing countries as a way of improving the financing and delivery of public healthcare. Decision autonomy under healthcare decentralization would determine the role and scope of responsibility of local authorities. Jalal Mohammed, Nicola North, and Toni Ashton analyze decision autonomy within decentralized services in Fiji. They conclude that the narrow decision space allowed to local entities might have limited the benefits of decentralization on users and providers. To discuss the costs and benefits of healthcare decentralization this paper uses the U-form and M-form typology to further illustrate the role of decision autonomy under healthcare decentralization. This paper argues that when evaluating healthcare decentralization, it is important to determine whether the benefits from decentralization are greater than its costs. The U-form and M-form framework is proposed as a useful typology to evaluate different types of institutional arrangements under healthcare decentralization. Under this model, the more decentralized organizational form (M-form is superior if the benefits from flexibility exceed the costs of duplication and the more centralized organizational form (U-form is superior if the savings from economies of scale outweigh the costly decision-making process from the center to the regions. Budgetary and financial autonomy and effective mechanisms to maintain local governments accountable for their spending behavior are key decision autonomy variables that could sway the cost-benefit analysis of healthcare decentralization.

  1. A Decentralized Approach to the Formulation of Hypotheses: A Hierarchical Structural Model for a Prion Self-Assembled System

    Science.gov (United States)

    Wang, Mingyang; Zhang, Feifei; Song, Chao; Shi, Pengfei; Zhu, Jin

    2016-07-01

    Innovation in hypotheses is a key transformative driver for scientific development. The conventional centralized hypothesis formulation approach, where a dominant hypothesis is typically derived from a primary phenomenon, can, inevitably, impose restriction on the range of conceivable experiments and legitimate hypotheses, and ultimately impede understanding of the system of interest. We report herein the proposal of a decentralized approach for the formulation of hypotheses, through initial preconception-free phenomenon accumulation and subsequent reticular logical reasoning processes. The two-step approach can provide an unbiased, panoramic view of the system and as such should enable the generation of a set of more coherent and therefore plausible hypotheses. As a proof-of-concept demonstration of the utility of this open-ended approach, a hierarchical model has been developed for a prion self-assembled system, allowing insight into hitherto elusive static and dynamic features associated with this intriguing structure.

  2. Decentralized models of agricultural marketing as a strategy for social inclusion in Colombia: the case Exofruit SAS

    Directory of Open Access Journals (Sweden)

    Francisco Javier Arias Vargas

    2015-09-01

    Full Text Available This paper analyzes a model of decentralized marketing cape gooseberry (Physalis peruviana as an alternative to traditional wholesale channels; where brokers obtain higher profits; while farmers receive little profit for their product and the customer receives an expensive product. The investigative process development for nine months under a descriptive exploratory approach to data collection and triangulation of it to build the case. The project currently benefits 40 farmers; victims of armed conflict in the village of Mesopotamia Antioquia Union have joined the project, which has particularities like organic production of 1.2 tons per month of product, recovery of abandoned land; and equitable distribution of profits and the way for negotiations between farmers and the seller as a new proposal of peasant association.

  3. Decentralized Decision Making Toward Educational Goals.

    Science.gov (United States)

    Monahan, William W.; Johnson, Homer M.

    This monograph provides guidelines to help those school districts considering a more decentralized form of management. The authors discuss the levels at which different types of decisions should be made, describe the changing nature of the educational environment, identify different centralization-decentralization models, and suggest a flexible…

  4. Robust Decentralized Formation Flight Control

    Directory of Open Access Journals (Sweden)

    Zhao Weihua

    2011-01-01

    Full Text Available Motivated by the idea of multiplexed model predictive control (MMPC, this paper introduces a new framework for unmanned aerial vehicles (UAVs formation flight and coordination. Formulated using MMPC approach, the whole centralized formation flight system is considered as a linear periodic system with control inputs of each UAV subsystem as its periodic inputs. Divided into decentralized subsystems, the whole formation flight system is guaranteed stable if proper terminal cost and terminal constraints are added to each decentralized MPC formulation of the UAV subsystem. The decentralized robust MPC formulation for each UAV subsystem with bounded input disturbances and model uncertainties is also presented. Furthermore, an obstacle avoidance control scheme for any shape and size of obstacles, including the nonapriorily known ones, is integrated under the unified MPC framework. The results from simulations demonstrate that the proposed framework can successfully achieve robust collision-free formation flights.

  5. Multiobjective optimization of cluster-scale urban water systems investigating alternative water sources and level of decentralization

    Science.gov (United States)

    Newman, J. P.; Dandy, G. C.; Maier, H. R.

    2014-10-01

    In many regions, conventional water supplies are unable to meet projected consumer demand. Consequently, interest has arisen in integrated urban water systems, which involve the reclamation or harvesting of alternative, localized water sources. However, this makes the planning and design of water infrastructure more difficult, as multiple objectives need to be considered, water sources need to be selected from a number of alternatives, and end uses of these sources need to be specified. In addition, the scale at which each treatment, collection, and distribution network should operate needs to be investigated. In order to deal with this complexity, a framework for planning and designing water infrastructure taking into account integrated urban water management principles is presented in this paper and applied to a rural greenfield development. Various options for water supply, and the scale at which they operate were investigated in order to determine the life-cycle trade-offs between water savings, cost, and GHG emissions as calculated from models calibrated using Australian data. The decision space includes the choice of water sources, storage tanks, treatment facilities, and pipes for water conveyance. For each water system analyzed, infrastructure components were sized using multiobjective genetic algorithms. The results indicate that local water sources are competitive in terms of cost and GHG emissions, and can reduce demand on the potable system by as much as 54%. Economies of scale in treatment dominated the diseconomies of scale in collection and distribution of water. Therefore, water systems that connect large clusters of households tend to be more cost efficient and have lower GHG emissions. In addition, water systems that recycle wastewater tended to perform better than systems that captured roof-runoff. Through these results, the framework was shown to be effective at identifying near optimal trade-offs between competing objectives, thereby enabling

  6. The Wolf and the Caribou: Coexistence of Decentralized Economies and Competitive Markets

    Directory of Open Access Journals (Sweden)

    Andreas Freund

    2018-05-01

    Full Text Available Starting with BitTorrent and then Bitcoin, decentralized technologies have been on the rise over the last 15+ years, gaining significant momentum in the last 2+ years with the advent of platform ecosystems such as the Blockchain platform Ethereum. New projects have evolved from decentralized games to marketplaces to open funding models to decentralized autonomous organizations. The hype around cryptocurrency and the valuation of innovative projects drove the market cap of cryptocurrencies to over a trillion dollars at one point in 2017. These high valued technologies are now enabling something new: globally scaled and decentralized business models. Despite their valuation and the hype, these new business ecosystems are frail. This is not only because the underlying technology is rapidly evolving, but also because competitive markets see a profit opportunity in exponential cryptocurrency returns. This extracts value from these ecosystems, which could lead to their collapse, if unchecked. In this paper, we explore novel ways for decentralized economies to protect themselves from, and coexist with, competitive markets at a global scale utilizing decentralized technologies such as Blockchain.

  7. Large scale model testing

    International Nuclear Information System (INIS)

    Brumovsky, M.; Filip, R.; Polachova, H.; Stepanek, S.

    1989-01-01

    Fracture mechanics and fatigue calculations for WWER reactor pressure vessels were checked by large scale model testing performed using large testing machine ZZ 8000 (with a maximum load of 80 MN) at the SKODA WORKS. The results are described from testing the material resistance to fracture (non-ductile). The testing included the base materials and welded joints. The rated specimen thickness was 150 mm with defects of a depth between 15 and 100 mm. The results are also presented of nozzles of 850 mm inner diameter in a scale of 1:3; static, cyclic, and dynamic tests were performed without and with surface defects (15, 30 and 45 mm deep). During cyclic tests the crack growth rate in the elastic-plastic region was also determined. (author). 6 figs., 2 tabs., 5 refs

  8. Small scale models equal large scale savings

    International Nuclear Information System (INIS)

    Lee, R.; Segroves, R.

    1994-01-01

    A physical scale model of a reactor is a tool which can be used to reduce the time spent by workers in the containment during an outage and thus to reduce the radiation dose and save money. The model can be used for worker orientation, and for planning maintenance, modifications, manpower deployment and outage activities. Examples of the use of models are presented. These were for the La Salle 2 and Dresden 1 and 2 BWRs. In each case cost-effectiveness and exposure reduction due to the use of a scale model is demonstrated. (UK)

  9. Decentralized electricity production. v. 1 and 2

    International Nuclear Information System (INIS)

    1991-01-01

    The first part of the symposium is concerned with market analysis, case studies and prospectives for the decentralized production of electricity in France: cogeneration, heat networks, municipal waste incineration, etc. Financing systems and microeconomical analysis are presented. The second part is devoted to macroeconomical outlooks (France and Europe mainly) on decentralized electricity production (cogeneration, small-scale hydroelectric power plants), to other countries experience (PV systems connected to the grid, cogeneration, etc.) and to price contracts and regulations

  10. Decentralized Software Architecture

    National Research Council Canada - National Science Library

    Khare, Rohit

    2002-01-01

    .... While the term "decentralization" is familiar from political and economic contexts, it has been applied extensively, if indiscriminately, to describe recent trends in software architecture towards...

  11. Lab-scale co-digestion of kitchen waste and brown water for a preliminary performance evaluation of a decentralized waste and wastewater management.

    Science.gov (United States)

    Lavagnolo, Maria Cristina; Girotto, Francesca; Hirata, Osamu; Cossu, Raffaello

    2017-08-01

    An overall interaction is manifested between wastewater and solid waste management schemes. At the Laboratory of Environmental Engineering (LISA) of the University of Padova, Italy, the scientific and technical implications of putting into practice a decentralized waste and wastewater treatment based on the separation of grey water, brown water (BW - faecal matter) and yellow water (YW - urine) are currently undergoing investigation in the Aquanova Project. An additional aim of this concept is the source segregation of kitchen waste (KW) for subsequent anaerobic co-digestion with BW. To determine an optimal mixing ratio and temperature for use in the treatment of KW, BW, and eventually YW, by means of anaerobic digestion, a series of lab-scale batch tests were performed. Organic mixtures of KW and BW performed much better (max. 520mlCH 4 /gVS) in terms of methane yields than the individual substrates alone (max. 220mlCH 4 /gVS). A small concentration of urine proved to have a positive effect on anaerobic digestion performance, possibly due to the presence of micronutrients in YW. When considering high YW concentrations in the anaerobically digested mixtures, no ammonia inhibition was observed until a 30% and 10% YW content was added under mesophilic and thermophilic conditions, respectively. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Replication of urban innovations - prioritization of strategies for the replication of Dhaka's community-based decentralized composting model.

    Science.gov (United States)

    Yedla, Sudhakar

    2012-01-01

    Dhaka's community-based decentralized composting (DCDC) is a successful demonstration of solid waste management by adopting low-cost technology, local resources community participation and partnerships among the various actors involved. This paper attempts to understand the model, necessary conditions, strategies and their priorities to replicate DCDC in the other developing cities of Asia. Thirteen strategies required for its replication are identified and assessed based on various criteria, namely transferability, longevity, economic viability, adaptation and also overall replication. Priority setting by multi-criteria analysis by applying analytic hierarchy process revealed that immediate transferability without long-term and economic viability consideration is not advisable as this would result in unsustainable replication of DCDC. Based on the analysis, measures to ensure the product quality control; partnership among stakeholders (public-private-community); strategies to achieve better involvement of the private sector in solid waste management (entrepreneurship in approach); simple and low-cost technology; and strategies to provide an effective interface among the complementing sectors are identified as important strategies for its replication.

  13. Drift Scale THM Model

    International Nuclear Information System (INIS)

    Rutqvist, J.

    2004-01-01

    This model report documents the drift scale coupled thermal-hydrological-mechanical (THM) processes model development and presents simulations of the THM behavior in fractured rock close to emplacement drifts. The modeling and analyses are used to evaluate the impact of THM processes on permeability and flow in the near-field of the emplacement drifts. The results from this report are used to assess the importance of THM processes on seepage and support in the model reports ''Seepage Model for PA Including Drift Collapse'' and ''Abstraction of Drift Seepage'', and to support arguments for exclusion of features, events, and processes (FEPs) in the analysis reports ''Features, Events, and Processes in Unsaturated Zone Flow and Transport and Features, Events, and Processes: Disruptive Events''. The total system performance assessment (TSPA) calculations do not use any output from this report. Specifically, the coupled THM process model is applied to simulate the impact of THM processes on hydrologic properties (permeability and capillary strength) and flow in the near-field rock around a heat-releasing emplacement drift. The heat generated by the decay of radioactive waste results in elevated rock temperatures for thousands of years after waste emplacement. Depending on the thermal load, these temperatures are high enough to cause boiling conditions in the rock, resulting in water redistribution and altered flow paths. These temperatures will also cause thermal expansion of the rock, with the potential of opening or closing fractures and thus changing fracture permeability in the near-field. Understanding the THM coupled processes is important for the performance of the repository because the thermally induced permeability changes potentially effect the magnitude and spatial distribution of percolation flux in the vicinity of the drift, and hence the seepage of water into the drift. This is important because a sufficient amount of water must be available within a

  14. Agent-Based Modeling for Testing and Designing Novel Decentralized Command and Control System Paradigms

    National Research Council Canada - National Science Library

    Bonabeau, Eric; Hunt, Carl W; Gaudiano, Paolo

    2003-01-01

    Agent-based modeling (ABM) is a recent simulation modeling technique that consists of modeling a system from the bottom up, capturing the interactions taking place between the system's constituent units...

  15. Analysis of Decentralized Control for Absorption Cycle Heat Pumps

    DEFF Research Database (Denmark)

    Vinther, Kasper; Just Nielsen, Rene; Nielsen, Kirsten Mølgaard

    2015-01-01

    Email Print Request Permissions This paper investigates decentralized control structures for absorption cycle heat pumps and a dynamic nonlinear model of a single-effect LiBr-water absorption system is used as case study. The model has four controllable inputs, which can be used to stabilize...... the operation of the heat pump under different load conditions. Different feasible input-output pairings are analyzed by computation of relative gain array matrices and scaled condition numbers, which indicate the best pairing choice and the potential of each input-output set. Further, it is possible...... to minimize the effect of cross couplings and improve stability with the right pairing of input and output. Simulation of selected candidate input-output pairings demonstrate that decentralized control can provide stable operation of the heat pump....

  16. The Two Edge Knife of Decentralization

    OpenAIRE

    Umam, Ahmad Khoirul

    2011-01-01

    A centralistic government model has become a trend in a number of developing countries, in which the ideosycretic aspect becomes pivotal key in the policy making. The situation constitutes authoritarianism, cronyism, and corruption. To break the impasse, the decentralized system is proposed to make people closer to the public policy making. Decentralization is also convinced to be the solution to create a good governance. But a number of facts in the developing countries demonstrates that dec...

  17. Centralized, Decentralized, and Hybrid Purchasing Organizations

    DEFF Research Database (Denmark)

    Bals, Lydia; Turkulainen, Virpi

    This paper addresses one of the focal issues in purchasing and supply management – global sourcing – from an organizational design perspective. In particular, we elaborate the traditional classification of global sourcing organization designs into centralized, decentralized, and hybrid models. We...... organization we can identify organization designs beyond the classical centralization-decentralization continuum. We also provide explanations for the observed organization design at GCC. The study contributes to research on purchasing and supply management as well as research on organization design....

  18. Adaptive Neural Networks Decentralized FTC Design for Nonstrict-Feedback Nonlinear Interconnected Large-Scale Systems Against Actuator Faults.

    Science.gov (United States)

    Li, Yongming; Tong, Shaocheng

    The problem of active fault-tolerant control (FTC) is investigated for the large-scale nonlinear systems in nonstrict-feedback form. The nonstrict-feedback nonlinear systems considered in this paper consist of unstructured uncertainties, unmeasured states, unknown interconnected terms, and actuator faults (e.g., bias fault and gain fault). A state observer is designed to solve the unmeasurable state problem. Neural networks (NNs) are used to identify the unknown lumped nonlinear functions so that the problems of unstructured uncertainties and unknown interconnected terms can be solved. By combining the adaptive backstepping design principle with the combination Nussbaum gain function property, a novel NN adaptive output-feedback FTC approach is developed. The proposed FTC controller can guarantee that all signals in all subsystems are bounded, and the tracking errors for each subsystem converge to a small neighborhood of zero. Finally, numerical results of practical examples are presented to further demonstrate the effectiveness of the proposed control strategy.The problem of active fault-tolerant control (FTC) is investigated for the large-scale nonlinear systems in nonstrict-feedback form. The nonstrict-feedback nonlinear systems considered in this paper consist of unstructured uncertainties, unmeasured states, unknown interconnected terms, and actuator faults (e.g., bias fault and gain fault). A state observer is designed to solve the unmeasurable state problem. Neural networks (NNs) are used to identify the unknown lumped nonlinear functions so that the problems of unstructured uncertainties and unknown interconnected terms can be solved. By combining the adaptive backstepping design principle with the combination Nussbaum gain function property, a novel NN adaptive output-feedback FTC approach is developed. The proposed FTC controller can guarantee that all signals in all subsystems are bounded, and the tracking errors for each subsystem converge to a small

  19. Review and Extension of Suitability Assessment Indicators of Weather Model Output for Analyzing Decentralized Energy Systems

    Directory of Open Access Journals (Sweden)

    Hans Schermeyer

    2015-12-01

    Full Text Available Electricity from renewable energy sources (RES-E is gaining more and more influence in traditional energy and electricity markets in Europe and around the world. When modeling RES-E feed-in on a high temporal and spatial resolution, energy systems analysts frequently use data generated by numerical weather models as input since there is no spatial inclusive and comprehensive measurement data available. However, the suitability of such model data depends on the research questions at hand and should be inspected individually. This paper focuses on new methodologies to carry out a performance evaluation of solar irradiation data provided by a numerical weather model when investigating photovoltaic feed-in and effects on the electricity grid. Suitable approaches of time series analysis are researched from literature and applied to both model and measurement data. The findings and limits of these approaches are illustrated and a new set of validation indicators is presented. These novel indicators complement the assessment by measuring relevant key figures in energy systems analysis: e.g., gradients in energy supply, maximum values and volatility. Thus, the results of this paper contribute to the scientific community of energy systems analysts and researchers who aim at modeling RES-E feed-in on a high temporal and spatial resolution using weather model data.

  20. Treatment initiation, program attrition and patient treatment outcomes associated with scale-up and decentralization of HIV care in rural Malawi.

    Directory of Open Access Journals (Sweden)

    Megan McGuire

    Full Text Available OBJECTIVE: To describe patient antiretroviral therapy (cART outcomes associated with intensive decentralization of services in a rural HIV program in Malawi. METHODS: Longitudinal analysis of data from HIV-infected patients starting cART between August 2001 and December 2008 and of a cross-sectional immunovirological assessment conducted 12 (±2 months after therapy start. One-year mortality, lost to follow-up, and attrition (deaths and lost to follow-up rates were estimated with exact Poisson 95% confidence intervals (CI by type of care delivery and year of initiation. Association of virological suppression (<50 copies/mL and immunological success (CD4 gain ≥100 cells/µL, with type of care was investigated using multiple logistic regression. RESULTS: During the study period, 4322 cART patients received centralized care and 11,090 decentralized care. At therapy start, patients treated in decentralized health facilities had higher median CD4 count levels (167 vs. 130 cell/µL, P<0.0001 than other patients. Two years after cART start, program attrition was lower in decentralized than centralized facilities (9.9 per 100 person-years, 95% CI: 9.5-10.4 vs. 20.8 per 100 person-years, 95% CI: 19.7-22.0. One year after treatment start, differences in immunological success (adjusted OR=1.23, 95% CI: 0.83-1.83, and viral suppression (adjusted OR=0.80, 95% CI: 0.56-1.14 between patients followed at centralized and decentralized facilities were not statistically significant. CONCLUSIONS: In rural Malawi, 1- and 2-year program attrition was lower in decentralized than in centralized health facilities and no statistically significant differences in one-year immunovirological outcomes were observed between the two health care levels. Longer follow-up is needed to confirm these results.

  1. Computing for Decentralized Systems (lecture 2)

    CERN Multimedia

    CERN. Geneva

    2018-01-01

    With the rise of Bitcoin, Ethereum, and other cryptocurrencies it is becoming apparent the paradigm shift towards decentralized computing. Computer engineers will need to understand this shift when developing systems in the coming years. Transferring value over the Internet is just one of the first working use cases of decentralized systems, but it is expected they will be used for a number of different services such as general purpose computing, data storage, or even new forms of governance. Decentralized systems, however, pose a series of challenges that cannot be addressed with traditional approaches in computing. Not having a central authority implies truth must be agreed upon rather than simply trusted and, so, consensus protocols, cryptographic data structures like the blockchain, and incentive models like mining rewards become critical for the correct behavior of decentralized system. This series of lectures will be a fast track to introduce these fundamental concepts through working examples and pra...

  2. Computing for Decentralized Systems (lecture 1)

    CERN Multimedia

    CERN. Geneva

    2018-01-01

    With the rise of Bitcoin, Ethereum, and other cryptocurrencies it is becoming apparent the paradigm shift towards decentralized computing. Computer engineers will need to understand this shift when developing systems in the coming years. Transferring value over the Internet is just one of the first working use cases of decentralized systems, but it is expected they will be used for a number of different services such as general purpose computing, data storage, or even new forms of governance. Decentralized systems, however, pose a series of challenges that cannot be addressed with traditional approaches in computing. Not having a central authority implies truth must be agreed upon rather than simply trusted and, so, consensus protocols, cryptographic data structures like the blockchain, and incentive models like mining rewards become critical for the correct behavior of decentralized system. This series of lectures will be a fast track to introduce these fundamental concepts through working examples and pra...

  3. Sustainable model for financial viability of decentralized biomass gasifier based power projects

    NARCIS (Netherlands)

    Palit, D.; Malhotra, R.; Kumar, Atul

    2011-01-01

    This paper made a modest attempt for designing a sustainable model for financial viability of biomass gasifier power projects for enhancing electricity access in India and other developing countries. For long term sustainability of distributed generation projects in remote rural areas, viability

  4. Innovation, Decentralization and Planning in a Multi-Region Model of Schumpeterian Economic Growth

    NARCIS (Netherlands)

    Batabyal, A.; Nijkamp, P.

    2014-01-01

    We study innovation and the resulting Schumpeterian economic growth that this innovation gives rise to in a model with N heterogeneous regions. For each region i where i = 1,…,N, our analysis leads to six findings. First, we define the balanced growth path (BGP) allocations and the equilibrium of

  5. Decentralized model predictive based load frequency control in an interconnected power system

    Energy Technology Data Exchange (ETDEWEB)

    Mohamed, T.H., E-mail: tarekhie@yahoo.co [High Institute of Energy, South Valley University (Egypt); Bevrani, H., E-mail: bevrani@ieee.or [Dept. of Electrical Engineering and Computer Science, University of Kurdistan (Iran, Islamic Republic of); Hassan, A.A., E-mail: aahsn@yahoo.co [Faculty of Engineering, Dept. of Electrical Engineering, Minia University, Minia (Egypt); Hiyama, T., E-mail: hiyama@cs.kumamoto-u.ac.j [Dept. of Electrical Engineering and Computer Science, Kumamoto University, Kumamoto (Japan)

    2011-02-15

    This paper presents a new load frequency control (LFC) design using the model predictive control (MPC) technique in a multi-area power system. The MPC technique has been designed such that the effect of the uncertainty due to governor and turbine parameters variation and load disturbance is reduced. Each local area controller is designed independently such that stability of the overall closed-loop system is guaranteed. A frequency response model of multi-area power system is introduced, and physical constraints of the governors and turbines are considered. The model was employed in the MPC structures. Digital simulations for both two and three-area power systems are provided to validate the effectiveness of the proposed scheme. The results show that, with the proposed MPC technique, the overall closed-loop system performance demonstrated robustness in the face of uncertainties due to governors and turbines parameters variation and loads disturbances. A performance comparison between the proposed controller and a classical integral control scheme is carried out confirming the superiority of the proposed MPC technique.

  6. Decentralized model predictive based load frequency control in an interconnected power system

    International Nuclear Information System (INIS)

    Mohamed, T.H.; Bevrani, H.; Hassan, A.A.; Hiyama, T.

    2011-01-01

    This paper presents a new load frequency control (LFC) design using the model predictive control (MPC) technique in a multi-area power system. The MPC technique has been designed such that the effect of the uncertainty due to governor and turbine parameters variation and load disturbance is reduced. Each local area controller is designed independently such that stability of the overall closed-loop system is guaranteed. A frequency response model of multi-area power system is introduced, and physical constraints of the governors and turbines are considered. The model was employed in the MPC structures. Digital simulations for both two and three-area power systems are provided to validate the effectiveness of the proposed scheme. The results show that, with the proposed MPC technique, the overall closed-loop system performance demonstrated robustness in the face of uncertainties due to governors and turbines parameters variation and loads disturbances. A performance comparison between the proposed controller and a classical integral control scheme is carried out confirming the superiority of the proposed MPC technique.

  7. Organizational decentralization in radiology.

    Science.gov (United States)

    Aas, I H Monrad

    2006-01-01

    At present, most hospitals have a department of radiology where images are captured and interpreted. Decentralization is the opposite of centralization and means 'away from the centre'. With a Picture Archiving and Communication System (PACS) and broadband communications, transmitting radiology images between sites will be far easier than before. Qualitative interviews of 26 resource persons were performed in Norway. There was a response rate of 90%. Decentralization of radiology interpretations seems less relevant than centralization, but several forms of decentralization have a role to play. The respondents mentioned several advantages, including exploitation of capacity and competence. They also mentioned several disadvantages, including splitting professional communities and reduced contact between radiologists and clinicians. With the new technology decentralization and centralization of image interpretation are important possibilities in organizational change. This will be important for the future of teleradiology.

  8. Decentralization: Another Perspective

    Science.gov (United States)

    Chapman, Robin

    1973-01-01

    This paper attempts to pursue the centralization-decentralization dilemma. A setting for this discussion is provided by noting some of the uses of terminology, followed by a consideration of inherent difficulties in conceptualizing. (Author)

  9. Sustainable model for financial viability of decentralized biomass gasifier based power projects

    International Nuclear Information System (INIS)

    Palit, Debajit; Malhotra, Ramit; Kumar, Atul

    2011-01-01

    This paper made a modest attempt for designing a sustainable model for financial viability of biomass gasifier power projects for enhancing electricity access in India and other developing countries. For long term sustainability of distributed generation projects in remote rural areas, viability from both project implementing agency (PIA) and the end-users need to be ensured. The minimum required prices of electricity from both PIA and end-user perspective have been estimated. While for PIA the cost recovery is the key for viability, the affordability to pay the electricity cost is crucial for the end users. Analysis carried out in this paper on the basis of data obtained from operational projects implemented in India reveal that it is essential to operate the system at a higher capacity utilization factor. While this can be achieved though creating convergence with locally relevant economic activity, it is also observed that micro-enterprises cannot pay beyond a certain price of electricity to keep it sustainable. This paper sets forth a case for developing a regulatory mechanism to extend the tariff fixation for the projects and providing cross-subsidies to ensure long term sustainability of off-grid project. - Highlights: → We design sustainable financial model for viability of biomass gasifier projects. → Analysis based on field data obtained from operational projects in India. Estimated electricity pricing from both implementing agency and end-users perspective. → A regulatory mechanism for tariff fixation and cross subsidization is recommended.

  10. International Symposia on Scale Modeling

    CERN Document Server

    Ito, Akihiko; Nakamura, Yuji; Kuwana, Kazunori

    2015-01-01

    This volume thoroughly covers scale modeling and serves as the definitive source of information on scale modeling as a powerful simplifying and clarifying tool used by scientists and engineers across many disciplines. The book elucidates techniques used when it would be too expensive, or too difficult, to test a system of interest in the field. Topics addressed in the current edition include scale modeling to study weather systems, diffusion of pollution in air or water, chemical process in 3-D turbulent flow, multiphase combustion, flame propagation, biological systems, behavior of materials at nano- and micro-scales, and many more. This is an ideal book for students, both graduate and undergraduate, as well as engineers and scientists interested in the latest developments in scale modeling. This book also: Enables readers to evaluate essential and salient aspects of profoundly complex systems, mechanisms, and phenomena at scale Offers engineers and designers a new point of view, liberating creative and inno...

  11. Decentralization of storm runoff via engagement of social and cultural capitals - implications for the management of flood risk at the municipal scale

    Science.gov (United States)

    This research tests a novel method that focuses limited community resources on a decentralized approach to storm water management. A reverse auction was used to relieve legal constraints on management implementation on private land. Residents voluntarily bid on rain gardens and r...

  12. Partially Decentralized Control Architectures for Satellite Formations

    Science.gov (United States)

    Carpenter, J. Russell; Bauer, Frank H.

    2002-01-01

    In a partially decentralized control architecture, more than one but less than all nodes have supervisory capability. This paper describes an approach to choosing the number of supervisors in such au architecture, based on a reliability vs. cost trade. It also considers the implications of these results for the design of navigation systems for satellite formations that could be controlled with a partially decentralized architecture. Using an assumed cost model, analytic and simulation-based results indicate that it may be cheaper to achieve a given overall system reliability with a partially decentralized architecture containing only a few supervisors, than with either fully decentralized or purely centralized architectures. Nominally, the subset of supervisors may act as centralized estimation and control nodes for corresponding subsets of the remaining subordinate nodes, and act as decentralized estimation and control peers with respect to each other. However, in the context of partially decentralized satellite formation control, the absolute positions and velocities of each spacecraft are unique, so that correlations which make estimates using only local information suboptimal only occur through common biases and process noise. Covariance and monte-carlo analysis of a simplified system show that this lack of correlation may allow simplification of the local estimators while preserving the global optimality of the maneuvers commanded by the supervisors.

  13. Treatment initiation, program attrition and patient treatment outcomes associated with scale-up and decentralization of HIV care in rural Malawi.

    Science.gov (United States)

    McGuire, Megan; Pinoges, Loretxu; Kanapathipillai, Rupa; Munyenyembe, Tamika; Huckabee, Martha; Makombe, Simon; Szumilin, Elisabeth; Heinzelmann, Annette; Pujades-Rodríguez, Mar

    2012-01-01

    To describe patient antiretroviral therapy (cART) outcomes associated with intensive decentralization of services in a rural HIV program in Malawi. Longitudinal analysis of data from HIV-infected patients starting cART between August 2001 and December 2008 and of a cross-sectional immunovirological assessment conducted 12 (±2) months after therapy start. One-year mortality, lost to follow-up, and attrition (deaths and lost to follow-up) rates were estimated with exact Poisson 95% confidence intervals (CI) by type of care delivery and year of initiation. Association of virological suppression (centralized care and 11,090 decentralized care. At therapy start, patients treated in decentralized health facilities had higher median CD4 count levels (167 vs. 130 cell/µL, Pdecentralized than centralized facilities (9.9 per 100 person-years, 95% CI: 9.5-10.4 vs. 20.8 per 100 person-years, 95% CI: 19.7-22.0). One year after treatment start, differences in immunological success (adjusted OR=1.23, 95% CI: 0.83-1.83), and viral suppression (adjusted OR=0.80, 95% CI: 0.56-1.14) between patients followed at centralized and decentralized facilities were not statistically significant. In rural Malawi, 1- and 2-year program attrition was lower in decentralized than in centralized health facilities and no statistically significant differences in one-year immunovirological outcomes were observed between the two health care levels. Longer follow-up is needed to confirm these results.

  14. Centralized vs. de-centralized multinationals and taxes

    OpenAIRE

    Nielsen, Søren Bo; Raimondos-Møller, Pascalis; Schjelderup, Guttorm

    2005-01-01

    The paper examines how country tax differences affect a multinational enterprise's choice to centralize or de-centralize its decision structure. Within a simple model that emphasizes the multiple conflicting roles of transfer prices in MNEs – here, as a strategic pre-commitment device and a tax manipulation instrument –, we show that (de-)centralized decisions are more profitable when tax differentials are (small) large. Keywords: Centralized vs. de-centralized decisions, taxes, MNEs. ...

  15. Decentralization and Governance in Indonesia

    NARCIS (Netherlands)

    Holzhacker, Ronald; Wittek, Rafael; Woltjer, Johan

    2016-01-01

    I. Theoretical Reflections on Decentralization and Governance for Sustainable Society 1. Decentralization and Governance for Sustainable Society in Indonesia Ronald Holzhacker, Rafael Wittek and Johan Woltjer 2. Good Governance Contested: Exploring Human Rights and Sustainability as Normative Goals

  16. Towards Automatic Decentralized Control Structure Selection

    DEFF Research Database (Denmark)

    for decentralized control is determined automatically, and the resulting decentralized control structure is automatically tuned using standard techniques. Dynamic simulation of the resulting process system gives immediate feedback to the process design engineer regarding practical operability of the process......A subtask in integration of design and control of chemical processes is the selection of a control structure. Automating the selection of the control structure enables sequential integration of process and controld esign. As soon as the process is specified or computed, a structure....... The control structure selection problem is formulated as a special MILP employing cost coefficients which are computed using Parseval's theorem combined with RGA and IMC concepts. This approach enables selection and tuning of large-scale plant-wide decentralized controllers through efficient combination...

  17. Towards Automatic Decentralized Control Structure Selection

    DEFF Research Database (Denmark)

    Jørgensen, John Bagterp; Jørgensen, Sten Bay

    2000-01-01

    for decentralized control is determined automatically, and the resulting decentralized control structure is automatically tuned using standard techniques. Dynamic simulation of the resulting process system gives immediate feedback to the process design engineer regarding practical operability of the process......A subtask in integration of design and control of chemical processes is the selection of a control structure. Automating the selection of the control structure enables sequential integration of process and control design. As soon as the process is specified or computed, a structure....... The control structure selection problem is formulated as a special MILP employing cost coefficients which are computed using Parseval's theorem combined with RGA and IMC concepts. This approach enables selection and tuning of large-scale plant-wide decentralized controllers through efficient combination...

  18. An ecological vegetation-activated sludge process (V-ASP) for decentralized wastewater treatment: system development, treatment performance, and mathematical modeling.

    Science.gov (United States)

    Yuan, Jiajia; Dong, Wenyi; Sun, Feiyun; Li, Pu; Zhao, Ke

    2016-05-01

    An environment-friendly decentralized wastewater treatment process that is comprised of activated sludge process (ASP) and wetland vegetation, named as vegetation-activated sludge process (V-ASP), was developed for decentralized wastewater treatment. The long-term experimental results evidenced that the vegetation sequencing batch reactor (V-SBR) process had consistently stable higher removal efficiencies of organic substances and nutrients from domestic wastewater compared with traditional sequencing batch reactor (SBR). The vegetation allocated into V-SBR system could not only remove nutrients through its vegetation transpiration ratio but also provide great surface area for microorganism activity enhancement. This high vegetation transpiration ratio enhanced nutrients removal effectiveness from wastewater mainly by flux enhancement, oxygen and substrate transportation acceleration, and vegetation respiration stimulation. A mathematical model based on ASM2d was successfully established by involving the specific function of vegetation to simulate system performance. The simulation results on the influence of operational parameters on V-ASP treatment effectiveness demonstrated that V-SBR had a high resistance to seasonal temperature fluctuations and influent loading shocking.

  19. Centralization vs. Decentralization: A Location Analysis Approach for Librarians

    Science.gov (United States)

    Raffel, Jeffrey; Shishko, Robert

    1972-01-01

    An application of location theory to the question of centralized versus decentralized library facilities for a university, with relevance for special libraries is presented. The analysis provides models for a single library, for two or more libraries, or for decentralized facilities. (6 references) (Author/NH)

  20. Spatial optimization for decentralized non-potable water reuse

    Science.gov (United States)

    Kavvada, Olga; Nelson, Kara L.; Horvath, Arpad

    2018-06-01

    Decentralization has the potential to reduce the scale of the piped distribution network needed to enable non-potable water reuse (NPR) in urban areas by producing recycled water closer to its point of use. However, tradeoffs exist between the economies of scale of treatment facilities and the size of the conveyance infrastructure, including energy for upgradient distribution of recycled water. To adequately capture the impacts from distribution pipes and pumping requirements, site-specific conditions must be accounted for. In this study, a generalized framework (a heuristic modeling approach using geospatial algorithms) is developed that estimates the financial cost, the energy use, and the greenhouse gas emissions associated with NPR (for toilet flushing) as a function of scale of treatment and conveyance networks with the goal of determining the optimal degree of decentralization. A decision-support platform is developed to assess and visualize NPR system designs considering topography, economies of scale, and building size. The platform can be used for scenario development to explore the optimal system size based on the layout of current or new buildings. The model also promotes technology innovation by facilitating the systems-level comparison of options to lower costs, improve energy efficiency, and lower greenhouse gas emissions.

  1. The Rhetoric of Decentralization

    Science.gov (United States)

    Ravitch, Diane

    1974-01-01

    Questions the rationale for and possible consequences of political decentralization of New York City. Suggests that the disadvantages--reduced level of professionalism, increased expense in multiple government operation, "stabilization" of residential segregation, necessity for budget negotiations because of public disclosure of tax…

  2. Decentralized Blended Acquisition

    NARCIS (Netherlands)

    Berkhout, A.J.

    2013-01-01

    The concept of blending and deblending is reviewed, making use of traditional and dispersed source arrays. The network concept of distributed blended acquisition is introduced. A million-trace robot system is proposed, illustrating that decentralization may bring about a revolution in the way we

  3. Decentralized control and filtering in interconnected dynamical systems

    CERN Document Server

    Mahmoud, Magdi S

    2011-01-01

    Based on the many approaches available for dealing with large-scale systems (LSS), Decentralized Control and Filtering in Interconnected Dynamical Systems supplies a rigorous framework for studying the analysis, stability, and control problems of LSS. Providing an overall assessment of LSS theories, it addresses model order reduction, parametric uncertainties, time delays, and control estimator gain perturbations. Taking readers on a guided tour through LSS, the book examines recent trends and approaches and reviews past methods and results from a contemporary perspective. It traces the progre

  4. MACROECONOMIC IMPACT OF DECENTRALIZATION

    Directory of Open Access Journals (Sweden)

    Emilia Cornelia STOICA

    2014-05-01

    Full Text Available The concept of decentralization has a variety of expressions, but the meaning generally accepted refers to the transfer of authority and responsibility of the public functions from central government to sub-national public entities or even to the private sector. Decentralization process is complex, affecting many aspects of social and economic life and public management, and its design and implementation cover several stages, depending on the cyclical and structural developments of the country. From an economic perspective, decentralization is seen as a means of primary importance in terms of improving the effectiveness and efficiency of public services and macroeconomic stability due to the redistribution of public finances while in a much closer logic of the government policy objectives. But the decentralization process behaves as well some risks, because it involves the implementation of appropriate mechanisms for the establishment of income and expenditure programming at the subnational level, which, if is not correlated with macroeconomic policy imperatives can lead to major imbalances, both financially as in termes of economic and social life. Equally, ensuring the balance of the budget at the local level is imperative to fulfill, this goal imposing a legal framework and specific procedures to size transfers of public funds, targeted or untargeted. Also, public and local authorities have to adopt appropriate laws and regulations such that sub-national public entities can access loans - such as bank loans or debentures from domestic or external market - in terms of a strict monitoring national financial stability. In all aspects of decentralization - political, administrative, financial -, public authorities should develop and implement the most effective mechanisms to coordinate macroeconomic objectives and both sectoral and local interests and establish clear responsibilities - exclusive or shared - for all parties involved in the

  5. Scale modelling in LMFBR safety

    International Nuclear Information System (INIS)

    Cagliostro, D.J.; Florence, A.L.; Abrahamson, G.R.

    1979-01-01

    This paper reviews scale modelling techniques used in studying the structural response of LMFBR vessels to HCDA loads. The geometric, material, and dynamic similarity parameters are presented and identified using the methods of dimensional analysis. Complete similarity of the structural response requires that each similarity parameter be the same in the model as in the prototype. The paper then focuses on the methods, limitations, and problems of duplicating these parameters in scale models and mentions an experimental technique for verifying the scaling. Geometric similarity requires that all linear dimensions of the prototype be reduced in proportion to the ratio of a characteristic dimension of the model to that of the prototype. The overall size of the model depends on the structural detail required, the size of instrumentation, and the costs of machining and assemblying the model. Material similarity requires that the ratio of the density, bulk modulus, and constitutive relations for the structure and fluid be the same in the model as in the prototype. A practical choice of a material for the model is one with the same density and stress-strain relationship as the operating temperature. Ni-200 and water are good simulant materials for the 304 SS vessel and the liquid sodium coolant, respectively. Scaling of the strain rate sensitivity and fracture toughness of materials is very difficult, but may not be required if these effects do not influence the structural response of the reactor components. Dynamic similarity requires that the characteristic pressure of a simulant source equal that of the prototype HCDA for geometrically similar volume changes. The energy source is calibrated in the geometry and environment in which it will be used to assure that heat transfer between high temperature loading sources and the coolant simulant and that non-equilibrium effects in two-phase sources are accounted for. For the geometry and flow conitions of interest, the

  6. On the Use of a Block Analog of the Gerschgorin Circle-Theorem in the Design of Decentralized Control of a Class of Large-Scale Systems

    Directory of Open Access Journals (Sweden)

    Ole A. Solheim

    1981-04-01

    Full Text Available The paper deals with the design of decentralized control of interconnected dynamic systems. It is assumed that each subsystem has its own control input and that the interconnections are through the states of the other subsystems. The purpose of the present paper is to investigate the possibility of using the so-called block Gerschgorin theorem to evaluate the stability of the total system, given the local controllers. This theorem enables us to determine inclusion regions for the eigenvalues of the total system and these regions are usually sharper than those obtained by the usual Gerschgorin circle theorem.

  7. Promoting collaboration and cultural competence for physician assistant and physical therapist students: A cross-cultural decentralized interprofessional education (IPE) model.

    Science.gov (United States)

    Oliveira, Kathleen De; North, Sara; Beck, Barbra; Hopp, Jane

    2015-01-01

    As the United States health care model progresses towards medical teams and the country's population continues to diversify, the need for health professional education programs to develop and implement culturally specific interprofessional education (IPE) becomes increasingly imperative. A wide range of models exists for delivering and implementing IPE in health education, but none have included the cultural components that are vital in educating the health professional. A cross-cultural decentralized IPE model for physician assistant (PA) and physical therapy (PT) students was developed. This three-part IPE series was created using an established cultural curricular model and began with the exploration of self, continued with the examination of various dimensions of culture, and concluded with the exploration of the intersection between health and culture. We assessed student satisfaction of the IPE experiences and students' engagement and attitudes towards IPE using a three-item open-ended questionnaire administered after each cross-cultural activity and the Interprofessional Education Series Survey (IESS) upon the completion of the series. IESS responses showed that PA and PT students reported benefits in interprofessional collaboration and cultural awareness and expressed overall satisfaction with the series. Qualitative analysis revealed growth in student response depth consistent with the scaffolded focus of each IPE module in the series. The trends in this three-part series suggest that institutions looking to develop culturally inclusive IPE educational initiatives may have success through a decentralized model mirroring the effective cultural progression focused on addressing exploration of self, examination of various dimensions of culture, and exploration of the intersection between health and culture.

  8. Optimal management of phenylketonuria: a centralized expert team is more successful than a decentralized model of care.

    Science.gov (United States)

    Camfield, Carol S; Joseph, Marissa; Hurley, Teresa; Campbell, Karen; Sanderson, Susan; Camfield, Peter R

    2004-07-01

    To compare phenylketonuria (PKU) management by a centralized, expert team in the Province of Nova Scotia (NS) with the decentralized approach in New Brunswick (NB). Retrospective chart review documented frequency of outpatient visits, phenylalanine (Phe) concentration, and medical formula use. Structured telephone interviews with the 8 regional NB dietitians (NB-D) documented their knowledge and support in PKU management. Patients with PKU (n=108; age, birth to 42 years) reside in NB (n=69) and NS (n=39). More were lost to contact in NB than in NS (9/69 vs 1/39) and more were completely off diet in NB than in NS (24/60 vs 1/38, P=.05). All 15 children 95% in NS. Mental handicap or borderline intelligence was common in both NB (44%) and NS (42%). All NB-D wished additional specialized medical, nursing, or social work assistance. PKU management appears to be more effective with an expert, coordinated team approach.

  9. Global scale groundwater flow model

    Science.gov (United States)

    Sutanudjaja, Edwin; de Graaf, Inge; van Beek, Ludovicus; Bierkens, Marc

    2013-04-01

    As the world's largest accessible source of freshwater, groundwater plays vital role in satisfying the basic needs of human society. It serves as a primary source of drinking water and supplies water for agricultural and industrial activities. During times of drought, groundwater sustains water flows in streams, rivers, lakes and wetlands, and thus supports ecosystem habitat and biodiversity, while its large natural storage provides a buffer against water shortages. Yet, the current generation of global scale hydrological models does not include a groundwater flow component that is a crucial part of the hydrological cycle and allows the simulation of groundwater head dynamics. In this study we present a steady-state MODFLOW (McDonald and Harbaugh, 1988) groundwater model on the global scale at 5 arc-minutes resolution. Aquifer schematization and properties of this groundwater model were developed from available global lithological model (e.g. Dürr et al., 2005; Gleeson et al., 2010; Hartmann and Moorsdorff, in press). We force the groundwtaer model with the output from the large-scale hydrological model PCR-GLOBWB (van Beek et al., 2011), specifically the long term net groundwater recharge and average surface water levels derived from routed channel discharge. We validated calculated groundwater heads and depths with available head observations, from different regions, including the North and South America and Western Europe. Our results show that it is feasible to build a relatively simple global scale groundwater model using existing information, and estimate water table depths within acceptable accuracy in many parts of the world.

  10. Analysis and design of robust decentralized controllers for nonlinear systems

    Energy Technology Data Exchange (ETDEWEB)

    Schoenwald, D.A.

    1993-07-01

    Decentralized control strategies for nonlinear systems are achieved via feedback linearization techniques. New results on optimization and parameter robustness of non-linear systems are also developed. In addition, parametric uncertainty in large-scale systems is handled by sensitivity analysis and optimal control methods in a completely decentralized framework. This idea is applied to alleviate uncertainty in friction parameters for the gimbal joints on Space Station Freedom. As an example of decentralized nonlinear control, singular perturbation methods and distributed vibration damping are merged into a control strategy for a two-link flexible manipulator.

  11. Leadership and the Decentralized Control of Schools

    Science.gov (United States)

    Steinberg, Matthew P.

    2013-01-01

    This review examines the literature related to leadership and the decentralized control of schools. It first considers the distinctive goals of public and private agencies, the specific constraints that shape the autonomy of leaders in different sectors, and the ways in which new models of public management are infusing public agencies with…

  12. Critical Systems Thinking on Decentralization: the Corporate ...

    African Journals Online (AJOL)

    This article calls for the devolution of power by large organizations to their subsidiaries or subordinate units – mainly Strategic Business Units (SBUs). It proposes more decentralized models of management and outlines a new theory taking a critical systems thinking approach. Corporations are advised to attack and ...

  13. Decentralization in Ethiopia

    OpenAIRE

    Gemechu, Mulugeta Debebbe

    2012-01-01

    Ethiopia officially launched the District Level Decentralization Program (DLDP) by the year 2002. The program flagged core objectives such as institutionalizing viable development centers at local levels, deepening devolution of power, enhancing the democratization process through broad-based participatory strategy, promoting good governance and improving service delivery. Since the inception of this program two strategic planning terms (one strategic term is five years) have already elapsed ...

  14. Centralized vs decentralized contests

    OpenAIRE

    Beviá, Carmen; Corchón, Luis C.

    2015-01-01

    We compare two contests, decentralized in which there are several independent contests with non overlapping contestants and centralized in which all contestants fight for a unique prize which is the sum of all prizes in the small contests. We study the relationship between payoffs and efforts between these two contests. The first author acknowledges financial support from ECO2008-04756 (Grupo Consolidado-C), SGR2014-515 and PROMETEO/2013/037. The second author acknowledges financial suppor...

  15. Policy Implementation Decentralization Government in Indonesia

    Directory of Open Access Journals (Sweden)

    Kardin M. Simanjuntak

    2015-06-01

    Full Text Available Decentralization in Indonesia is that reforms not completed and until the current implementation is not maximized or have not been successful. The essence of decentralization is internalising cost and benefit' for the people and how the government closer to the people. That's the most important essence of essence 'decentralization’. However, the implementation of decentralization in Indonesia is still far from the expectations. It is shown that only benefits of decentralization elite and local authorities, decentralization is a neo-liberal octopus, decentralization of public services are lacking in character, decentralization without institutional efficiency, decentralization fosters corruption in the area, and quasi-fiscal decentralization.

  16. Decentral Smart Grid Control

    Science.gov (United States)

    Schäfer, Benjamin; Matthiae, Moritz; Timme, Marc; Witthaut, Dirk

    2015-01-01

    Stable operation of complex flow and transportation networks requires balanced supply and demand. For the operation of electric power grids—due to their increasing fraction of renewable energy sources—a pressing challenge is to fit the fluctuations in decentralized supply to the distributed and temporally varying demands. To achieve this goal, common smart grid concepts suggest to collect consumer demand data, centrally evaluate them given current supply and send price information back to customers for them to decide about usage. Besides restrictions regarding cyber security, privacy protection and large required investments, it remains unclear how such central smart grid options guarantee overall stability. Here we propose a Decentral Smart Grid Control, where the price is directly linked to the local grid frequency at each customer. The grid frequency provides all necessary information about the current power balance such that it is sufficient to match supply and demand without the need for a centralized IT infrastructure. We analyze the performance and the dynamical stability of the power grid with such a control system. Our results suggest that the proposed Decentral Smart Grid Control is feasible independent of effective measurement delays, if frequencies are averaged over sufficiently large time intervals.

  17. Decentral Smart Grid Control

    International Nuclear Information System (INIS)

    Schäfer, Benjamin; Matthiae, Moritz; Timme, Marc; Witthaut, Dirk

    2015-01-01

    Stable operation of complex flow and transportation networks requires balanced supply and demand. For the operation of electric power grids—due to their increasing fraction of renewable energy sources—a pressing challenge is to fit the fluctuations in decentralized supply to the distributed and temporally varying demands. To achieve this goal, common smart grid concepts suggest to collect consumer demand data, centrally evaluate them given current supply and send price information back to customers for them to decide about usage. Besides restrictions regarding cyber security, privacy protection and large required investments, it remains unclear how such central smart grid options guarantee overall stability. Here we propose a Decentral Smart Grid Control, where the price is directly linked to the local grid frequency at each customer. The grid frequency provides all necessary information about the current power balance such that it is sufficient to match supply and demand without the need for a centralized IT infrastructure. We analyze the performance and the dynamical stability of the power grid with such a control system. Our results suggest that the proposed Decentral Smart Grid Control is feasible independent of effective measurement delays, if frequencies are averaged over sufficiently large time intervals. (paper)

  18. Holographic models with anisotropic scaling

    Science.gov (United States)

    Brynjolfsson, E. J.; Danielsson, U. H.; Thorlacius, L.; Zingg, T.

    2013-12-01

    We consider gravity duals to d+1 dimensional quantum critical points with anisotropic scaling. The primary motivation comes from strongly correlated electron systems in condensed matter theory but the main focus of the present paper is on the gravity models in their own right. Physics at finite temperature and fixed charge density is described in terms of charged black branes. Some exact solutions are known and can be used to obtain a maximally extended spacetime geometry, which has a null curvature singularity inside a single non-degenerate horizon, but generic black brane solutions in the model can only be obtained numerically. Charged matter gives rise to black branes with hair that are dual to the superconducting phase of a holographic superconductor. Our numerical results indicate that holographic superconductors with anisotropic scaling have vanishing zero temperature entropy when the back reaction of the hair on the brane geometry is taken into account.

  19. Energy and air emission implications of a decentralized wastewater system

    International Nuclear Information System (INIS)

    Shehabi, Arman; Stokes, Jennifer R; Horvath, Arpad

    2012-01-01

    Both centralized and decentralized wastewater systems have distinct engineering, financial and societal benefits. This paper presents a framework for analyzing the environmental effects of decentralized wastewater systems and an evaluation of the environmental impacts associated with two currently operating systems in California, one centralized and one decentralized. A comparison of energy use, greenhouse gas emissions and criteria air pollutants from the systems shows that the scale economies of the centralized plant help lower the environmental burden to less than a fifth of that of the decentralized utility for the same volume treated. The energy and emission burdens of the decentralized plant are reduced when accounting for high-yield wastewater reuse if it supplants an energy-intensive water supply like a desalination one. The centralized facility also reduces greenhouse gases by flaring methane generated during the treatment process, while methane is directly emitted from the decentralized system. The results are compelling enough to indicate that the life-cycle environmental impacts of decentralized designs should be carefully evaluated as part of the design process. (letter)

  20. Economic analysis of centralized vs. decentralized electronic data capture in multi-center clinical studies.

    Science.gov (United States)

    Walden, Anita; Nahm, Meredith; Barnett, M Edwina; Conde, Jose G; Dent, Andrew; Fadiel, Ahmed; Perry, Theresa; Tolk, Chris; Tcheng, James E; Eisenstein, Eric L

    2011-01-01

    New data management models are emerging in multi-center clinical studies. We evaluated the incremental costs associated with decentralized vs. centralized models. We developed clinical research network economic models to evaluate three data management models: centralized, decentralized with local software, and decentralized with shared database. Descriptive information from three clinical research studies served as inputs for these models. The primary outcome was total data management costs. Secondary outcomes included: data management costs for sites, local data centers, and central coordinating centers. Both decentralized models were more costly than the centralized model for each clinical research study: the decentralized with local software model was the most expensive. Decreasing the number of local data centers and case book pages reduced cost differentials between models. Decentralized vs. centralized data management in multi-center clinical research studies is associated with increases in data management costs.

  1. Decentralized robust control design using LMI

    Directory of Open Access Journals (Sweden)

    Dušan Krokavec

    2008-03-01

    Full Text Available The paper deals with application of decentralized controllers for large-scale systems with subsystems interaction and system matrices uncertainties. The desired stability of the whole system is guaranteed while at the same time the tolerable bounds in the uncertainties due to structural changes are maximized. The design approach is based on the linear matrix inequalities (LMI techniques adaptation for stabilizing controller design.

  2. Environmental aspects of decentralized electricity production

    International Nuclear Information System (INIS)

    Henry, J.P.

    1991-01-01

    Renewable energy sources are the focus of considerable interest because they do not place future generations at risk; the development of cogeneration has been favorably received on the whole because it uses energy that would otherwise be lost. Difficulties are sometimes encountered in the development of small-scale hydroelectric facilities (older facilities negative aspects, over production impression in France, etc.). Environmental protection regulations do not distinguish between centralized and decentralized electricity production, but between large and small production facilities

  3. Decentralized central heating

    Energy Technology Data Exchange (ETDEWEB)

    Savic, S.; Hudjera, A.

    1994-08-04

    The decentralized central heating is essentially based on new technical solutions for an independent heating unit, which allows up to 20% collectible energy savings and up to 15% savings in built-in-material. These savings are already made possible by the fact that the elements described under point A are thus eliminated from the classical heating. The thus superfluous made elements are replaced by new technical solutions described under point B - technical problem - and point E - patent claim. The technical solutions described in detail under point B and point E form together a technical unit and are essential parts of the invention protected by the patent. (author)

  4. Decentring the Creative Self

    DEFF Research Database (Denmark)

    Glaveanu, Vlad Petre; Lubart, Todd

    2014-01-01

    to themes depicting the interaction between these different others and the creator. Findings reveal both similarities and differences across the five domains in terms of the specific contribution of others to the creative process. Social interactions play a key formative, regulatory, motivational...... and informational role in relation to creative work. From ‘internalized’ to ‘distant’, other people are an integral part of the equation of creativity calling for a de-centring of the creative self and its re-centring in a social space of actions and interactions....

  5. Decentralized indirect methods for learning automata games.

    Science.gov (United States)

    Tilak, Omkar; Martin, Ryan; Mukhopadhyay, Snehasis

    2011-10-01

    We discuss the application of indirect learning methods in zero-sum and identical payoff learning automata games. We propose a novel decentralized version of the well-known pursuit learning algorithm. Such a decentralized algorithm has significant computational advantages over its centralized counterpart. The theoretical study of such a decentralized algorithm requires the analysis to be carried out in a nonstationary environment. We use a novel bootstrapping argument to prove the convergence of the algorithm. To our knowledge, this is the first time that such analysis has been carried out for zero-sum and identical payoff games. Extensive simulation studies are reported, which demonstrate the proposed algorithm's fast and accurate convergence in a variety of game scenarios. We also introduce the framework of partial communication in the context of identical payoff games of learning automata. In such games, the automata may not communicate with each other or may communicate selectively. This comprehensive framework has the capability to model both centralized and decentralized games discussed in this paper.

  6. On Decentralization and Life Satisfaction

    DEFF Research Database (Denmark)

    Bjørnskov, Christian; Dreher, Axel; Fischer, Justina A.V.

    2008-01-01

    We empirically analyze the impact of fiscal and political decentralization on subjective well-being in a cross-section of 60,000 individuals from 66 countries. More spending or revenue decentralization raises well-being while greater local autonomy is beneficial only via government consumption sp...

  7. A contingency approach to decentralization

    NARCIS (Netherlands)

    Fleurke, F.; Hulst, J.R.

    2006-01-01

    After decades of centralization, in 1980 the central government of the Netherlands embarked upon an ambitious project to decentralize the administrative system. It proclaimed a series of general decentralization measures that aimed to improve the performance of the administrative system and to boost

  8. A multi scale model for small scale plasticity

    International Nuclear Information System (INIS)

    Zbib, Hussein M.

    2002-01-01

    Full text.A framework for investigating size-dependent small-scale plasticity phenomena and related material instabilities at various length scales ranging from the nano-microscale to the mesoscale is presented. The model is based on fundamental physical laws that govern dislocation motion and their interaction with various defects and interfaces. Particularly, a multi-scale model is developed merging two scales, the nano-microscale where plasticity is determined by explicit three-dimensional dislocation dynamics analysis providing the material length-scale, and the continuum scale where energy transport is based on basic continuum mechanics laws. The result is a hybrid simulation model coupling discrete dislocation dynamics with finite element analyses. With this hybrid approach, one can address complex size-dependent problems, including dislocation boundaries, dislocations in heterogeneous structures, dislocation interaction with interfaces and associated shape changes and lattice rotations, as well as deformation in nano-structured materials, localized deformation and shear band

  9. Coalition or decentralization

    DEFF Research Database (Denmark)

    Mahdiraji, Hannan Amoozad; Govindan, Kannan; Zavadskas, Edmundas Kazimieras

    2014-01-01

    retailers. The Nash equilibrium and definition are used bearing in mind inventory and pricing and marketing cost as decision variables for this matter. This paper studies a three-echelon supply chain network and focuses on the value of integrating a pair of partners in the chain. In the decentralized case......, the supplier sets its own price, the manufacturer points out order quantity, wholesale price and backorder quantity, and the retailer charges the final retail price of the product and marketing product. Though there are multiple players at a single echelon level, each manufacturer supplies only a specific...... to enforce marketing effort any more. Supplier-manufacturer integration brings similar benefits. Under each scenario, all parties involved simultaneously set their strategies. Through a numerical experiment, 17 design cases (through designing experiments) have been developed and the total profit...

  10. Market model for a decentrally organized energy management system in the electric distribution grid. Basis for an internet-based management system; Marktmodell fuer ein dezentral organisiertes Energiemanagement im elektrischen Verteilnetz. Grundlage fuer ein internetbasiertes Managementsystem

    Energy Technology Data Exchange (ETDEWEB)

    Bendel, C.; Nestle, D.; Ringelstein, J. [Institut fuer Solare Energieversorgungstechnik (ISET), Kassel (Germany); Esser, A.; Moest, D.; Rentz, O. [Karlsruhe Univ. (Germany). Inst. fuer Industriebetriebslehre und Industrielle Produktion; Franke, M.; Geyer-Schulz, A. [Karlsruhe Univ. (Germany). Inst. fuer Informationswirtschaft und -management

    2007-07-01

    In this paper we present two key concepts for a future energy market with distributed electricity generation. First, we describe the energy management of distributed generators and loads with decentralized decision by bidirectional energy management interfaces. Second, we present a market platform supporting spontaneous trading by means of automated contract conclusion, innovative business models, and optimisation and controlling procedures for the demand as well as the supply side. (orig.)

  11. Subsidiarity in Principle: Decentralization of Water Resources Management

    Directory of Open Access Journals (Sweden)

    Ryan Stoa

    2014-05-01

    Full Text Available The subsidiarity principle of water resources management suggests that water management and service delivery should take place at the lowest appropriate governance level. The principle is attractive for several reasons, primarily because: 1 the governance level can be reduced to reflect environmental characteristics, such as the hydrological borders of a watershed that would otherwise cross administrative boundaries; 2 decentralization promotes community and stakeholder engagement when decision-making is localized; 3 inefficiencies are reduced by eliminating reliance on central government bureaucracies and budgetary constraints; and 4 laws and institutions can be adapted to reflect localized conditions at a scale where integrated natural resources management and climate change adaptation is more focused. Accordingly, the principle of subsidiarity has been welcomed by many states committed to decentralized governance, integrated water resources management, and/or civic participation. However, applications of decentralization have not been uniform, and in some cases have produced frustrating outcomes for states and water resources. Successful decentralization strategies are heavily dependent on dedicated financial resources and human resource capacity. This article explores the nexus between the principle of subsidiarity and the enabling environment, in the hope of articulating factors likely to contribute to, or detract from, the success of decentralized water resources management. Case studies from Haiti, Rwanda, and the United States’ Florida Water Management Districts provide examples of the varied stages of decentralization.

  12. Asynchronous decentralized method for interconnected electricity markets

    International Nuclear Information System (INIS)

    Huang, Anni; Joo, Sung-Kwan; Song, Kyung-Bin; Kim, Jin-Ho; Lee, Kisung

    2008-01-01

    This paper presents an asynchronous decentralized method to solve the optimization problem of interconnected electricity markets. The proposed method decomposes the optimization problem of combined electricity markets into individual optimization problems. The impact of neighboring markets' information is included in the objective function of the individual market optimization problem by the standard Lagrangian relaxation method. Most decentralized optimization methods use synchronous models of communication to exchange updated market information among markets during the iterative process. In this paper, however, the solutions of the individual optimization problems are coordinated through an asynchronous communication model until they converge to the global optimal solution of combined markets. Numerical examples are presented to demonstrate the advantages of the proposed asynchronous method over the existing synchronous methods. (author)

  13. Scaling laws for modeling nuclear reactor systems

    International Nuclear Information System (INIS)

    Nahavandi, A.N.; Castellana, F.S.; Moradkhanian, E.N.

    1979-01-01

    Scale models are used to predict the behavior of nuclear reactor systems during normal and abnormal operation as well as under accident conditions. Three types of scaling procedures are considered: time-reducing, time-preserving volumetric, and time-preserving idealized model/prototype. The necessary relations between the model and the full-scale unit are developed for each scaling type. Based on these relationships, it is shown that scaling procedures can lead to distortion in certain areas that are discussed. It is advised that, depending on the specific unit to be scaled, a suitable procedure be chosen to minimize model-prototype distortion

  14. Decentralized Quasi-Newton Methods

    Science.gov (United States)

    Eisen, Mark; Mokhtari, Aryan; Ribeiro, Alejandro

    2017-05-01

    We introduce the decentralized Broyden-Fletcher-Goldfarb-Shanno (D-BFGS) method as a variation of the BFGS quasi-Newton method for solving decentralized optimization problems. The D-BFGS method is of interest in problems that are not well conditioned, making first order decentralized methods ineffective, and in which second order information is not readily available, making second order decentralized methods impossible. D-BFGS is a fully distributed algorithm in which nodes approximate curvature information of themselves and their neighbors through the satisfaction of a secant condition. We additionally provide a formulation of the algorithm in asynchronous settings. Convergence of D-BFGS is established formally in both the synchronous and asynchronous settings and strong performance advantages relative to first order methods are shown numerically.

  15. Decentralized Consistent Updates in SDN

    KAUST Repository

    Nguyen, Thanh Dang

    2017-04-10

    We present ez-Segway, a decentralized mechanism to consistently and quickly update the network state while preventing forwarding anomalies (loops and blackholes) and avoiding link congestion. In our design, the centralized SDN controller only pre-computes information needed by the switches during the update execution. This information is distributed to the switches, which use partial knowledge and direct message passing to efficiently realize the update. This separation of concerns has the key benefit of improving update performance as the communication and computation bottlenecks at the controller are removed. Our evaluations via network emulations and large-scale simulations demonstrate the efficiency of ez-Segway, which compared to a centralized approach, improves network update times by up to 45% and 57% at the median and the 99th percentile, respectively. A deployment of a system prototype in a real OpenFlow switch and an implementation in P4 demonstrate the feasibility and low overhead of implementing simple network update functionality within switches.

  16. Spatial scale separation in regional climate modelling

    Energy Technology Data Exchange (ETDEWEB)

    Feser, F.

    2005-07-01

    In this thesis the concept of scale separation is introduced as a tool for first improving regional climate model simulations and, secondly, to explicitly detect and describe the added value obtained by regional modelling. The basic idea behind this is that global and regional climate models have their best performance at different spatial scales. Therefore the regional model should not alter the global model's results at large scales. The for this purpose designed concept of nudging of large scales controls the large scales within the regional model domain and keeps them close to the global forcing model whereby the regional scales are left unchanged. For ensemble simulations nudging of large scales strongly reduces the divergence of the different simulations compared to the standard approach ensemble that occasionally shows large differences for the individual realisations. For climate hindcasts this method leads to results which are on average closer to observed states than the standard approach. Also the analysis of the regional climate model simulation can be improved by separating the results into different spatial domains. This was done by developing and applying digital filters that perform the scale separation effectively without great computational effort. The separation of the results into different spatial scales simplifies model validation and process studies. The search for 'added value' can be conducted on the spatial scales the regional climate model was designed for giving clearer results than by analysing unfiltered meteorological fields. To examine the skill of the different simulations pattern correlation coefficients were calculated between the global reanalyses, the regional climate model simulation and, as a reference, of an operational regional weather analysis. The regional climate model simulation driven with large-scale constraints achieved a high increase in similarity to the operational analyses for medium-scale 2 meter

  17. Rethinking Decentralization in Education in terms of Administrative Problems

    Directory of Open Access Journals (Sweden)

    Vasiliki Papadopoulou

    2013-11-01

    Full Text Available The general purpose of this study is to thoroughly examine decentralization in education according to the literature and previous research, and to discuss the applicability of educational decentralization practices in Turkey. The literature was reviewed for the study and findings reported. It has been observed that decentralization in education practices were realized in many countries after the 1980’s. It is obvious that the educational system in Turkey has difficulty in meeting the needs, and encounters many problems due to its present centralist state. Educational decentralization can provide effective solutions for stakeholder engagement, educational financing and for problems in decision making and operation within the education system. However, the present state of local governments, the legal framework, geographical, cultural and social features indicate that Turkey’s conditions are not ready for decentralization in education. A decentralization model realized in the long run according to Turkey’s conditions, and as a result of a social consensus, can help resolve the problems of the Turkish education system.

  18. Modeling and simulation with operator scaling

    OpenAIRE

    Cohen, Serge; Meerschaert, Mark M.; Rosiński, Jan

    2010-01-01

    Self-similar processes are useful in modeling diverse phenomena that exhibit scaling properties. Operator scaling allows a different scale factor in each coordinate. This paper develops practical methods for modeling and simulating stochastic processes with operator scaling. A simulation method for operator stable Levy processes is developed, based on a series representation, along with a Gaussian approximation of the small jumps. Several examples are given to illustrate practical application...

  19. Decentralized and Modular Electrical Architecture

    Science.gov (United States)

    Elisabelar, Christian; Lebaratoux, Laurence

    2014-08-01

    This paper presents the studies made on the definition and design of a decentralized and modular electrical architecture that can be used for power distribution, active thermal control (ATC), standard inputs-outputs electrical interfaces.Traditionally implemented inside central unit like OBC or RTU, these interfaces can be dispatched in the satellite by using MicroRTU.CNES propose a similar approach of MicroRTU. The system is based on a bus called BRIO (Bus Réparti des IO), which is composed, by a power bus and a RS485 digital bus. BRIO architecture is made with several miniature terminals called BTCU (BRIO Terminal Control Unit) distributed in the spacecraft.The challenge was to design and develop the BTCU with very little volume, low consumption and low cost. The standard BTCU models are developed and qualified with a configuration dedicated to ATC, while the first flight model will fly on MICROSCOPE for PYRO actuations and analogue acquisitions. The design of the BTCU is made in order to be easily adaptable for all type of electric interface needs.Extension of this concept is envisaged for power conditioning and distribution unit, and a Modular PCDU based on BRIO concept is proposed.

  20. Electrochemical conversion technologies for optimal design of decentralized multi-energy systems : Modeling framework and technology assessment

    NARCIS (Netherlands)

    Gabrielli, Paolo; Gazzani, Matteo; Mazzotti, Marco

    2018-01-01

    The design and operation of integrated multi-energy systems require models that adequately describe the behavior of conversion and storage technologies. Typically, linear conversion performance or fixed data from technology manufacturers are employed, especially for new or advanced technologies.

  1. A Spatial Decision Support System to incorporate hydro-economic modeling results in the management of water resources under decentralized institutional arrangements in a semiarid reservoir region in Brazil

    Science.gov (United States)

    Alcoforado de Moraes, Márcia; Silva, Gerald; Siegmund-Schultze, Marianna

    2017-04-01

    The integration of economic and hydrological components in models, aimed to support evaluating alternatives of water allocation policies, is promising, though, challenging. Worldwide, these models have been used primarily in academia, and so far seldom by water managers for practical purposes. Ideally, the models should be available through a Decision Support System. The São Francisco River Basin in Northeast of Brazil has around 48% of its area in a semi-arid region. Irrigation and public water supply are the primary water use sectors, along with hydropower utilization. The water for electricity generation is stored in two large reservoirs, built 30 to 50 years ago under the premise of regulating flows for hydropower and controlling floods. Since 20 years, however, the law stipulates the multiple uses paradigm in a participatory and decentralized way. So far, only few rules laid down. Studies revealed that most of the respective institutions still needed to update their routines to the new paradigm. A hydro-economic model was developed and applied in order to determine the economically optimal water allocation of main users in that semiarid reservoir region. In order to make this model available to the decision makers, a minimum required is some form of manipulating data entry and output as well as some graphical interfaces. We propose and present the first features of a Spatial Decision Support System (SDSS) with dedicated hydro-economic modules in a web-based Geographic Information System (GIS) environment for integrated water resource management. The open model platform should include geoprocessing tasks and water user related data management. The hydro-economic geoprocessing will link to generic optimization modeling systems, such as EXCEL Solver, GAMS and MATLAB. The institutions are deliberating or deciding over water allocation at different scales could use the generated information on potential economic benefits as a transparent basis for discussion. In

  2. Modelling of rate effects at multiple scales

    DEFF Research Database (Denmark)

    Pedersen, R.R.; Simone, A.; Sluys, L. J.

    2008-01-01

    , the length scale in the meso-model and the macro-model can be coupled. In this fashion, a bridging of length scales can be established. A computational analysis of  a Split Hopkinson bar test at medium and high impact load is carried out at macro-scale and meso-scale including information from  the micro-scale.......At the macro- and meso-scales a rate dependent constitutive model is used in which visco-elasticity is coupled to visco-plasticity and damage. A viscous length scale effect is introduced to control the size of the fracture process zone. By comparison of the widths of the fracture process zone...

  3. An Ontology of Quality Initiatives and a Model for Decentralized, Collaborative Quality Management on the (Semantic) World Wide Web

    Science.gov (United States)

    2001-01-01

    This editorial provides a model of how quality initiatives concerned with health information on the World Wide Web may in the future interact with each other. This vision fits into the evolving "Semantic Web" architecture - ie, the prospective that the World Wide Web may evolve from a mess of unstructured, human-readable information sources into a global knowledge base with an additional layer providing richer and more meaningful relationships between resources. One first prerequisite for forming such a "Semantic Web" or "web of trust" among the players active in quality management of health information is that these initiatives make statements about themselves and about each other in a machine-processable language. I present a concrete model on how this collaboration could look, and provide some recommendations on what the role of the World Health Organization (WHO) and other policy makers in this framework could be. PMID:11772549

  4. Large Scale Computations in Air Pollution Modelling

    DEFF Research Database (Denmark)

    Zlatev, Z.; Brandt, J.; Builtjes, P. J. H.

    Proceedings of the NATO Advanced Research Workshop on Large Scale Computations in Air Pollution Modelling, Sofia, Bulgaria, 6-10 July 1998......Proceedings of the NATO Advanced Research Workshop on Large Scale Computations in Air Pollution Modelling, Sofia, Bulgaria, 6-10 July 1998...

  5. One-scale supersymmetric inflationary models

    International Nuclear Information System (INIS)

    Bertolami, O.; Ross, G.G.

    1986-01-01

    The reheating phase is studied in a class of supergravity inflationary models involving a two-component hidden sector in which the scale of supersymmetry breaking and the scale generating inflation are related. It is shown that these models have an ''entropy crisis'' in which there is a large entropy release after nucleosynthesis leading to unacceptable low nuclear abundances. (orig.)

  6. Trends in research on forestry decentralization policies

    DEFF Research Database (Denmark)

    Lund, Jens Friis; Rutt, Rebecca Leigh; Ribot, Jesse

    2018-01-01

    institutions; studies focusing on power and the role of elites in forestry decentralization, and; studies that historicize and contextualize forestry decentralization as reflective of broader societal phenomena. We argue that these strands reflect disciplinary differences in values, epistemologies, and methods...

  7. Query Optimizations over Decentralized RDF Graphs

    KAUST Repository

    Abdelaziz, Ibrahim; Mansour, Essam; Ouzzani, Mourad; Aboulnaga, Ashraf; Kalnis, Panos

    2017-01-01

    Applications in life sciences, decentralized social networks, Internet of Things, and statistical linked dataspaces integrate data from multiple decentralized RDF graphs via SPARQL queries. Several approaches have been proposed to optimize query

  8. Feedback-linearization and feedback-feedforward decentralized control for multimachine power system

    Energy Technology Data Exchange (ETDEWEB)

    De Tuglie, Enrico [Dipartimento di Ingegneria dell' Ambiente, e per lo Sviluppo Sostenibile - DIASS, Politecnico di Bari, Viale del Turismo 8, 74100 Taranto (Italy); Iannone, Silvio Marcello; Torelli, Francesco [Dipartimento di Elettrotecnica, ed Elettronica - DEE, Politecnico di Bari, Via Re David 200, 70125 Bari (Italy)

    2008-03-15

    In this paper a decentralized nonlinear controller for large-scale power systems is investigated. The proposed controller design is based on the input-output feedback linearization methodology. In order to overcome computational difficulties in adopting such methodology, the overall interconnected nonlinear system, given as n-order, is analyzed as a cascade connection of an n{sub 1}-order nonlinear subsystem and an n{sub 2}-order linear subsystem. The controller design is obtained by applying input-output feedback linearization to the nonlinear subsystem and adopting a tracking control scheme, based on feedback-feedforward technique, for the linear subsystem. In the assumed system model, which is characterised by an interconnected structure between generating units, a decentralised adaptive controller is implemented by decentralizing these constraints. The use of a totally decentralised controller implies a system performance decay with respect to performance when the system is equipped with a centralised controller. Fortunately, the robustness of the proposed controller, based on input-output feedback procedure, guarantees good performance in terms of disturbance even when disturbances are caused by decentralization of interconnection constraints. Test results, provided on the IEEE 30 bus test system, demonstrate the effectiveness and practical applicability of proposed methodology. (author)

  9. Decentralized Control of Autonomous Vehicles

    Science.gov (United States)

    2003-01-01

    Autonomous Vehicles by John S. Baras, Xiaobo Tan, Pedram Hovareshti CSHCN TR 2003-8 (ISR TR 2003-14) Report Documentation Page Form ApprovedOMB No. 0704...AND SUBTITLE Decentralized Control of Autonomous Vehicles 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT...Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std Z39-18 Decentralized Control of Autonomous Vehicles ∗ John S. Baras, Xiaobo Tan, and Pedram

  10. Ubiquitous consultation tool for decentral knowledge workers

    OpenAIRE

    Nazari Shirehjini, A.A.; Rühl, C.; Noll, S.

    2003-01-01

    The special issue of this initial study is to examine the current work situation of consulting companies, and to elaborate a concept for supporting decentralized working consultants. The concept addresses significant challenges of decentralized work processes by deploying the Peer-to-Peer methodology to decentralized expert and Knowledge Management, cooperation, and enterprise resource planning.

  11. Decentralized Pricing in Minimum Cost Spanning Trees

    DEFF Research Database (Denmark)

    Hougaard, Jens Leth; Moulin, Hervé; Østerdal, Lars Peter

    In the minimum cost spanning tree model we consider decentralized pricing rules, i.e. rules that cover at least the ecient cost while the price charged to each user only depends upon his own connection costs. We de ne a canonical pricing rule and provide two axiomatic characterizations. First......, the canonical pricing rule is the smallest among those that improve upon the Stand Alone bound, and are either superadditive or piece-wise linear in connection costs. Our second, direct characterization relies on two simple properties highlighting the special role of the source cost....

  12. Automatic Decentralized Clustering for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Wen Chih-Yu

    2005-01-01

    Full Text Available We propose a decentralized algorithm for organizing an ad hoc sensor network into clusters. Each sensor uses a random waiting timer and local criteria to determine whether to form a new cluster or to join a current cluster. The algorithm operates without a centralized controller, it operates asynchronously, and does not require that the location of the sensors be known a priori. Simplified models are used to estimate the number of clusters formed, and the energy requirements of the algorithm are investigated. The performance of the algorithm is described analytically and via simulation.

  13. Decentralized control: Status and outlook

    Czech Academy of Sciences Publication Activity Database

    Bakule, Lubomír

    2014-01-01

    Roč. 38, č. 1 (2014), s. 71-80 ISSN 1367-5788 R&D Projects: GA ČR GA13-02149S Institutional support: RVO:67985556 Keywords : decentralized control * networked control systems * event-triggered approach Subject RIV: BC - Control Systems Theory Impact factor: 2.518, year: 2014

  14. Peer Matcher : Decentralized Partnership Formation

    NARCIS (Netherlands)

    Bozdog, Nicolae Vladimir; Voulgaris, Spyros; Bal, Henri; van Halteren, Aart

    2015-01-01

    This paper presents Peer Matcher, a fully decentralized algorithm solving the k-clique matching problem. The aim of k-clique matching is to cluster a set of nodes having pair wise weights into k-size groups of maximal total weight. Since solving the problem requires exponential time, Peer Matcher

  15. Music Libraries: Centralization versus Decentralization.

    Science.gov (United States)

    Kuyper-Rushing, Lois

    2002-01-01

    Considers the decision that branch libraries, music libraries in particular, have struggled with concerning a centralized location in the main library versus a decentralized collection. Reports on a study of the Association of Research Libraries that investigated the location of music libraries, motivation for the location, degrees offered,…

  16. Multi-scale modeling of composites

    DEFF Research Database (Denmark)

    Azizi, Reza

    A general method to obtain the homogenized response of metal-matrix composites is developed. It is assumed that the microscopic scale is sufficiently small compared to the macroscopic scale such that the macro response does not affect the micromechanical model. Therefore, the microscopic scale......-Mandel’s energy principle is used to find macroscopic operators based on micro-mechanical analyses using the finite element method under generalized plane strain condition. A phenomenologically macroscopic model for metal matrix composites is developed based on constitutive operators describing the elastic...... to plastic deformation. The macroscopic operators found, can be used to model metal matrix composites on the macroscopic scale using a hierarchical multi-scale approach. Finally, decohesion under tension and shear loading is studied using a cohesive law for the interface between matrix and fiber....

  17. Rural Electrification through Decentralized Concentrating Solar Power: Technological and Socio-Economic Aspects

    Directory of Open Access Journals (Sweden)

    Sylvain Quoilin

    2013-09-01

    Full Text Available This paper presents the development of small-scale solar Organic Rankine Cycles for rural electrification in remote areas of Lesotho. It is subdivided in two parts. The first part deals with the success conditions of decentralized rural electrification projects. Through a literature survey, relevant guiding principles and recommendations are formulated. The second part of the paper describes the proposed system, which is designed in agreement with the formulated recommendations. A framework for benchmarking the performance and cost of various micro-utility platforms and rural electrification distribution models is proposed.

  18. Reaction Diffusion and Chemotaxis for Decentralized Gathering on FPGAs

    Directory of Open Access Journals (Sweden)

    Bernard Girau

    2009-01-01

    and rapid simulations of the complex dynamics of this reaction-diffusion model. Then we describe the FPGA implementation of the environment together with the agents, to study the major challenges that must be solved when designing a fast embedded implementation of the decentralized gathering model. We analyze the results according to the different goals of these hardware implementations.

  19. Decentralized neural control application to robotics

    CERN Document Server

    Garcia-Hernandez, Ramon; Sanchez, Edgar N; Alanis, Alma y; Ruz-Hernandez, Jose A

    2017-01-01

    This book provides a decentralized approach for the identification and control of robotics systems. It also presents recent research in decentralized neural control and includes applications to robotics. Decentralized control is free from difficulties due to complexity in design, debugging, data gathering and storage requirements, making it preferable for interconnected systems. Furthermore, as opposed to the centralized approach, it can be implemented with parallel processors. This approach deals with four decentralized control schemes, which are able to identify the robot dynamics. The training of each neural network is performed on-line using an extended Kalman filter (EKF). The first indirect decentralized control scheme applies the discrete-time block control approach, to formulate a nonlinear sliding manifold. The second direct decentralized neural control scheme is based on the backstepping technique, approximated by a high order neural network. The third control scheme applies a decentralized neural i...

  20. On scaling of human body models

    Directory of Open Access Journals (Sweden)

    Hynčík L.

    2007-10-01

    Full Text Available Human body is not an unique being, everyone is another from the point of view of anthropometry and mechanical characteristics which means that division of the human body population to categories like 5%-tile, 50%-tile and 95%-tile from the application point of view is not enough. On the other hand, the development of a particular human body model for all of us is not possible. That is why scaling and morphing algorithms has started to be developed. The current work describes the development of a tool for scaling of the human models. The idea is to have one (or couple of standard model(s as a base and to create other models based on these basic models. One has to choose adequate anthropometrical and biomechanical parameters that describe given group of humans to be scaled and morphed among.

  1. Decentralized guaranteed cost static output feedback vibration control for piezoelectric smart structures

    International Nuclear Information System (INIS)

    Jiang, Jian-ping; Li, Dong-xu

    2010-01-01

    This paper is devoted to the study of the decentralized guaranteed cost static output feedback vibration control for piezoelectric smart structures. A smart panel with collocated piezoelectric actuators and velocity sensors is modeled using a finite element method, and then the size of the model is reduced in the state space using the modal Hankel singular value. The necessary and sufficient conditions of decentralized guaranteed cost static output feedback control for the reduced system have been presented. The decentralized and centralized static output feedback matrices can be obtained from solving two linear matrix inequalities. A comparison between centralized control and decentralized control is performed in order to investigate their effectiveness in suppressing vibration of a smart panel. Numerical results show that when the system is subjected to initial displacement or white noise disturbance, the decentralized and centralized controls are both very effective and the control results are very close

  2. A Retrospective Analysis of the Development of Fiscal Decentralization

    Directory of Open Access Journals (Sweden)

    Rekova Nataliia Yu.

    2017-12-01

    Full Text Available The study forms the theoretical basis for the implementation of fiscal decentralization in Ukraine on the basis of determining the correspondence between the evolution of scientific approaches to the formation of an effective model of public administration and the degree of power centralization at a particular stage of the development of society. The views of thinkers of the ancient states of Egypt, Mesopotamia, India, China, Rome, Greece are generalized, and the priority of centralized public administration without segregation of centralization forms is determined. The degree of centralization in the period of development of feudal states is characterized. The scientific views of representatives of the neoinstitutional direction of economic thought are analyzed in detail, and the stages of the formation of decentralization, in particular fiscal, as a separate theory, are defined. The stages of and the corresponding organizational and legislative documents for the implementation of decentralization in Ukraine are outlined, and its results are characterized.

  3. Multi-scale Modeling of Arctic Clouds

    Science.gov (United States)

    Hillman, B. R.; Roesler, E. L.; Dexheimer, D.

    2017-12-01

    The presence and properties of clouds are critically important to the radiative budget in the Arctic, but clouds are notoriously difficult to represent in global climate models (GCMs). The challenge stems partly from a disconnect in the scales at which these models are formulated and the scale of the physical processes important to the formation of clouds (e.g., convection and turbulence). Because of this, these processes are parameterized in large-scale models. Over the past decades, new approaches have been explored in which a cloud system resolving model (CSRM), or in the extreme a large eddy simulation (LES), is embedded into each gridcell of a traditional GCM to replace the cloud and convective parameterizations to explicitly simulate more of these important processes. This approach is attractive in that it allows for more explicit simulation of small-scale processes while also allowing for interaction between the small and large-scale processes. The goal of this study is to quantify the performance of this framework in simulating Arctic clouds relative to a traditional global model, and to explore the limitations of such a framework using coordinated high-resolution (eddy-resolving) simulations. Simulations from the global model are compared with satellite retrievals of cloud fraction partioned by cloud phase from CALIPSO, and limited-area LES simulations are compared with ground-based and tethered-balloon measurements from the ARM Barrow and Oliktok Point measurement facilities.

  4. Decentralized substations for low-temperature district heating with no Legionella risk, and low return temperatures

    DEFF Research Database (Denmark)

    Yang, Xiaochen; Li, Hongwei; Svendsen, Svend

    2016-01-01

    . From the results, realizing LTDH by the decentralized substation unit, 30% of the annual distribution heat loss inside the building can be saved compared to a conventional system with medium-temperature district heating. Replacing the bypass pipe with an in-line supply pipe and a heat pump...... with domestic hot water (DHW) circulation. In this study, a system with decentralized substations was analysed as a solution to this problem. Furthermore, a modification for the decentralized substation system were proposed in order to reduce the average return temperature. Models of conventional system...... with medium-temperature district heating, decentralized substation system with LTDH, and innovative decentralized substation system with LTDH were built based on the information of a case building. The annual distribution heat loss and the operating costs of the three scenarios were calculated and compared...

  5. [Analysis of the healthcare service decentralization process in Côte d'Ivoire].

    Science.gov (United States)

    Soura, B D; Coulibaly, S S

    2014-01-01

    The decentralization of healthcare services is becoming increasingly important in strategies of public sector management. This concept is analyzed from various points of view, including legal, economic, political, and sociological. Several typologies have been proposed in the literature to analyze this decentralization process, which can take different forms ranging from simple deconcentration to more elaborate devolution. In some instances, decentralization can be analyzed by the degree of autonomy given to local authorities. This article applies these typologies to analyze the healthcare system decentralization process in Cote d'Ivoire. Special attention is paid to the new forms of community healthcare organizations. These decentralized structures enjoy a kind of autonomy, with characteristics closer to those of devolution. The model might serve as an example for population involvement in defining and managing healthcare problems in Cote d'Ivoire. We end with proposals for the improvement of the process.

  6. Site-Scale Saturated Zone Flow Model

    International Nuclear Information System (INIS)

    G. Zyvoloski

    2003-01-01

    The purpose of this model report is to document the components of the site-scale saturated-zone flow model at Yucca Mountain, Nevada, in accordance with administrative procedure (AP)-SIII.lOQ, ''Models''. This report provides validation and confidence in the flow model that was developed for site recommendation (SR) and will be used to provide flow fields in support of the Total Systems Performance Assessment (TSPA) for the License Application. The output from this report provides the flow model used in the ''Site-Scale Saturated Zone Transport'', MDL-NBS-HS-000010 Rev 01 (BSC 2003 [162419]). The Site-Scale Saturated Zone Transport model then provides output to the SZ Transport Abstraction Model (BSC 2003 [164870]). In particular, the output from the SZ site-scale flow model is used to simulate the groundwater flow pathways and radionuclide transport to the accessible environment for use in the TSPA calculations. Since the development and calibration of the saturated-zone flow model, more data have been gathered for use in model validation and confidence building, including new water-level data from Nye County wells, single- and multiple-well hydraulic testing data, and new hydrochemistry data. In addition, a new hydrogeologic framework model (HFM), which incorporates Nye County wells lithology, also provides geologic data for corroboration and confidence in the flow model. The intended use of this work is to provide a flow model that generates flow fields to simulate radionuclide transport in saturated porous rock and alluvium under natural or forced gradient flow conditions. The flow model simulations are completed using the three-dimensional (3-D), finite-element, flow, heat, and transport computer code, FEHM Version (V) 2.20 (software tracking number (STN): 10086-2.20-00; LANL 2003 [161725]). Concurrently, process-level transport model and methodology for calculating radionuclide transport in the saturated zone at Yucca Mountain using FEHM V 2.20 are being

  7. Comment on ‘Energy and air emission implications of a decentralized wastewater system’

    International Nuclear Information System (INIS)

    Vedachalam, Sridhar; Riha, Susan J

    2013-01-01

    In the article ‘Energy and air emission implications of a decentralized wastewater system’ published in Environmental Research Letters (2012 Environ. Res. Lett. 7 024007), Shehabi et al compared a decentralized and a centralized system on the basis of energy use, greenhouse gas emissions and air pollutants, and claimed that economies of scale lower the environmental impacts from a centralized system on a per-volume basis. In this comment, we present literature and data from New York State, USA to argue that the authors’ comparison between a small decentralized system (0.015 MGD) and a large centralized system (66.5 MGD) is unconventional and inappropriate. (comment)

  8. Decentralized Urban Solid Waste Management in Indonesia | CRDI ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Urban areas of Indonesia generate about 55 000 tonnes of solid waste per day, ... four models of decentralized solid waste management in low-income urban ... En partenariat avec l'Organization for Women in Science for the Developing ...

  9. Decentralized Receding Horizon Control and Coordination of Autonomous Vehicle Formations

    NARCIS (Netherlands)

    Keviczky, T.; Borelli, F.; Fregene, K.; Godbole, D.; Bals, G.J.

    2008-01-01

    This paper describes the application of a novel methodology for high-level control and coordination of autonomous vehicle teams and its demonstration on high-fidelity models of the organic air vehicle developed at Honeywell Laboratories. The scheme employs decentralized receding horizon controllers

  10. Centralized vs. De-centralized Multinationals and Taxes

    DEFF Research Database (Denmark)

    Nielsen, Søren Bo; Raimondos-Møller, Pascalis; Schjelderup, Guttorm

    2005-01-01

    The paper examines how country tax differences affect a multinational enterprise's choice to centralize or de-centralize its decision structure. Within a simple model that emphasizes the multiple conflicting roles of transfer prices in MNEs - here, as a strategic pre-commitment device and a tax...

  11. Centralized or decentralized electricity production

    International Nuclear Information System (INIS)

    Boer, H.A. de.

    1975-01-01

    Because of low overall efficiency in electric power generation, it is argued that energy provision based on gas, combined with locally decentralized electricity production, saves for the Netherlands slightly more fossile fuel than nuclear technologies and makes the country independent of uranium resources. The reason the Netherlands persues this approach is that a big part of the energy is finally used for heating in the normal or moderate temperatures

  12. Problems in decentralized data acquisition

    International Nuclear Information System (INIS)

    Eder, R.

    1985-04-01

    This paper describes INIS (International Nuclear Information System) which is operated by the International Atomic Energy Agency (IAEA) in collaboration with 73 Member States and 14 international organizations. INIS is a computerized system for collecting, processing and disseminating nuclear information. The collection and scanning of literature, input preparation and the dissemination of output are completely decentralized, the checking and merging of the information data are centralized. This paper shows the structure, management, processing and problem areas of this system. (Author)

  13. Design of scaled down structural models

    Science.gov (United States)

    Simitses, George J.

    1994-07-01

    In the aircraft industry, full scale and large component testing is a very necessary, time consuming, and expensive process. It is essential to find ways by which this process can be minimized without loss of reliability. One possible alternative is the use of scaled down models in testing and use of the model test results in order to predict the behavior of the larger system, referred to herein as prototype. This viewgraph presentation provides justifications and motivation for the research study, and it describes the necessary conditions (similarity conditions) for two structural systems to be structurally similar with similar behavioral response. Similarity conditions provide the relationship between a scaled down model and its prototype. Thus, scaled down models can be used to predict the behavior of the prototype by extrapolating their experimental data. Since satisfying all similarity conditions simultaneously is in most cases impractical, distorted models with partial similarity can be employed. Establishment of similarity conditions, based on the direct use of the governing equations, is discussed and their use in the design of models is presented. Examples include the use of models for the analysis of cylindrical bending of orthotropic laminated beam plates, of buckling of symmetric laminated rectangular plates subjected to uniform uniaxial compression and shear, applied individually, and of vibrational response of the same rectangular plates. Extensions and future tasks are also described.

  14. Distributed and decentralized state estimation in gas networks as distributed parameter systems.

    Science.gov (United States)

    Ahmadian Behrooz, Hesam; Boozarjomehry, R Bozorgmehry

    2015-09-01

    In this paper, a framework for distributed and decentralized state estimation in high-pressure and long-distance gas transmission networks (GTNs) is proposed. The non-isothermal model of the plant including mass, momentum and energy balance equations are used to simulate the dynamic behavior. Due to several disadvantages of implementing a centralized Kalman filter for large-scale systems, the continuous/discrete form of extended Kalman filter for distributed and decentralized estimation (DDE) has been extended for these systems. Accordingly, the global model is decomposed into several subsystems, called local models. Some heuristic rules are suggested for system decomposition in gas pipeline networks. In the construction of local models, due to the existence of common states and interconnections among the subsystems, the assimilation and prediction steps of the Kalman filter are modified to take the overlapping and external states into account. However, dynamic Riccati equation for each subsystem is constructed based on the local model, which introduces a maximum error of 5% in the estimated standard deviation of the states in the benchmarks studied in this paper. The performance of the proposed methodology has been shown based on the comparison of its accuracy and computational demands against their counterparts in centralized Kalman filter for two viable benchmarks. In a real life network, it is shown that while the accuracy is not significantly decreased, the real-time factor of the state estimation is increased by a factor of 10. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

  15. Wage Dispersion and Decentralization of Wage Bargaining

    DEFF Research Database (Denmark)

    Dahl, Christian M.; Le Maire, Christian Daniel; Munch, Jakob Roland

    in the individual worker's wage-setting system that facilitates identification of the effects of decentralization. Consistent with predictions we find that wages are more dispersed under firm-level bargaining compared to more centralized wage-setting systems. However, the differences across wage-setting systems......This paper studies how decentralization of wage bargaining from sector to firm level influences wage levels and wage dispersion. We use a detailed panel data set covering a period of decentralization in the Danish labor market. The decentralization process provides exogenous variation...

  16. Comments on intermediate-scale models

    Energy Technology Data Exchange (ETDEWEB)

    Ellis, J.; Enqvist, K.; Nanopoulos, D.V.; Olive, K.

    1987-04-23

    Some superstring-inspired models employ intermediate scales m/sub I/ of gauge symmetry breaking. Such scales should exceed 10/sup 16/ GeV in order to avoid prima facie problems with baryon decay through heavy particles and non-perturbative behaviour of the gauge couplings above m/sub I/. However, the intermediate-scale phase transition does not occur until the temperature of the Universe falls below O(m/sub W/), after which an enormous excess of entropy is generated. Moreover, gauge symmetry breaking by renormalization group-improved radiative corrections is inapplicable because the symmetry-breaking field has not renormalizable interactions at scales below m/sub I/. We also comment on the danger of baryon and lepton number violation in the effective low-energy theory.

  17. Comments on intermediate-scale models

    International Nuclear Information System (INIS)

    Ellis, J.; Enqvist, K.; Nanopoulos, D.V.; Olive, K.

    1987-01-01

    Some superstring-inspired models employ intermediate scales m I of gauge symmetry breaking. Such scales should exceed 10 16 GeV in order to avoid prima facie problems with baryon decay through heavy particles and non-perturbative behaviour of the gauge couplings above m I . However, the intermediate-scale phase transition does not occur until the temperature of the Universe falls below O(m W ), after which an enormous excess of entropy is generated. Moreover, gauge symmetry breaking by renormalization group-improved radiative corrections is inapplicable because the symmetry-breaking field has not renormalizable interactions at scales below m I . We also comment on the danger of baryon and lepton number violation in the effective low-energy theory. (orig.)

  18. Sustainable Supply of Safe Drinking Water for Underserved Households in Kenya: Investigating the Viability of Decentralized Solutions

    Directory of Open Access Journals (Sweden)

    Pauline Chepchirchir Cherunya

    2015-10-01

    Full Text Available Water quality and safe water sources are pivotal aspects of consideration for domestic water. Focusing on underserved households in Kenya, this study compared user perceptions and preferences on water-service provision options, particularly investigating the viability of decentralized models, such as the Safe Water Enterprise (SWE, as sustainable safe drinking water sources. Results showed that among a number of water-service provision options available, the majority of households regularly sourced their domestic water from more than one source (86% Ngoliba/Maguguni, 98% Kangemi Gichagi. A majority of households perceived their water sources to be unsafe to drink (84% Ngoliba/Maguguni, 73% Kangemi Gichagi. For this reason, drinking water was mainly chlorinated (48% Ngoliba/Maguguni, 33% Kangemi Gichagi or boiled (42% Ngoliba/Maguguni, 67% Kangemi Gichagi. However, this study also found that households in Kenya did not apply these household water treatment methods consistently, thus indicating inconsistency in safe water consumption. The SWE concept, a community-scale decentralized safe drinking water source, was a preferred option among households who perceived it to save time and to be less cumbersome as compared to boiling and chlorination. Willingness to pay for SWE water was also a positive indicator for its preference by the underserved households. However, the long-term applicability of such decentralized water provision models needs to be further investigated within the larger water-service provision context.

  19. Managing large-scale models: DBS

    International Nuclear Information System (INIS)

    1981-05-01

    A set of fundamental management tools for developing and operating a large scale model and data base system is presented. Based on experience in operating and developing a large scale computerized system, the only reasonable way to gain strong management control of such a system is to implement appropriate controls and procedures. Chapter I discusses the purpose of the book. Chapter II classifies a broad range of generic management problems into three groups: documentation, operations, and maintenance. First, system problems are identified then solutions for gaining management control are disucssed. Chapters III, IV, and V present practical methods for dealing with these problems. These methods were developed for managing SEAS but have general application for large scale models and data bases

  20. Scaled Experimental Modeling of VHTR Plenum Flows

    Energy Technology Data Exchange (ETDEWEB)

    ICONE 15

    2007-04-01

    Abstract The Very High Temperature Reactor (VHTR) is the leading candidate for the Next Generation Nuclear Power (NGNP) Project in the U.S. which has the goal of demonstrating the production of emissions free electricity and hydrogen by 2015. Various scaled heated gas and water flow facilities were investigated for modeling VHTR upper and lower plenum flows during the decay heat portion of a pressurized conduction-cooldown scenario and for modeling thermal mixing and stratification (“thermal striping”) in the lower plenum during normal operation. It was concluded, based on phenomena scaling and instrumentation and other practical considerations, that a heated water flow scale model facility is preferable to a heated gas flow facility and to unheated facilities which use fluids with ranges of density to simulate the density effect of heating. For a heated water flow lower plenum model, both the Richardson numbers and Reynolds numbers may be approximately matched for conduction-cooldown natural circulation conditions. Thermal mixing during normal operation may be simulated but at lower, but still fully turbulent, Reynolds numbers than in the prototype. Natural circulation flows in the upper plenum may also be simulated in a separate heated water flow facility that uses the same plumbing as the lower plenum model. However, Reynolds number scaling distortions will occur at matching Richardson numbers due primarily to the necessity of using a reduced number of channels connected to the plenum than in the prototype (which has approximately 11,000 core channels connected to the upper plenum) in an otherwise geometrically scaled model. Experiments conducted in either or both facilities will meet the objectives of providing benchmark data for the validation of codes proposed for NGNP designs and safety studies, as well as providing a better understanding of the complex flow phenomena in the plenums.

  1. Decentralized or Centralized Systems for Colleges and Universities?

    Science.gov (United States)

    Heydinger, Richard B.; Norris, Donald M.

    1979-01-01

    Arguments for and against decentralization of data management, analysis, and planning systems are presented. It is suggested that technological advances have encouraged decentralization. Caution in this direction is urged and the development of an articulated decentralization program is proposed. (SF)

  2. Biointerface dynamics--Multi scale modeling considerations.

    Science.gov (United States)

    Pajic-Lijakovic, Ivana; Levic, Steva; Nedovic, Viktor; Bugarski, Branko

    2015-08-01

    Irreversible nature of matrix structural changes around the immobilized cell aggregates caused by cell expansion is considered within the Ca-alginate microbeads. It is related to various effects: (1) cell-bulk surface effects (cell-polymer mechanical interactions) and cell surface-polymer surface effects (cell-polymer electrostatic interactions) at the bio-interface, (2) polymer-bulk volume effects (polymer-polymer mechanical and electrostatic interactions) within the perturbed boundary layers around the cell aggregates, (3) cumulative surface and volume effects within the parts of the microbead, and (4) macroscopic effects within the microbead as a whole based on multi scale modeling approaches. All modeling levels are discussed at two time scales i.e. long time scale (cell growth time) and short time scale (cell rearrangement time). Matrix structural changes results in the resistance stress generation which have the feedback impact on: (1) single and collective cell migrations, (2) cell deformation and orientation, (3) decrease of cell-to-cell separation distances, and (4) cell growth. Herein, an attempt is made to discuss and connect various multi scale modeling approaches on a range of time and space scales which have been proposed in the literature in order to shed further light to this complex course-consequence phenomenon which induces the anomalous nature of energy dissipation during the structural changes of cell aggregates and matrix quantified by the damping coefficients (the orders of the fractional derivatives). Deeper insight into the matrix partial disintegration within the boundary layers is useful for understanding and minimizing the polymer matrix resistance stress generation within the interface and on that base optimizing cell growth. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Complex scaling in the cluster model

    International Nuclear Information System (INIS)

    Kruppa, A.T.; Lovas, R.G.; Gyarmati, B.

    1987-01-01

    To find the positions and widths of resonances, a complex scaling of the intercluster relative coordinate is introduced into the resonating-group model. In the generator-coordinate technique used to solve the resonating-group equation the complex scaling requires minor changes in the formulae and code. The finding of the resonances does not need any preliminary guess or explicit reference to any asymptotic prescription. The procedure is applied to the resonances in the relative motion of two ground-state α clusters in 8 Be, but is appropriate for any systems consisting of two clusters. (author) 23 refs.; 5 figs

  4. DECENTRALIZATION OF MUNICIPAL SERVICES – LEARNING BY DOING

    Directory of Open Access Journals (Sweden)

    Cristina Elena NICOLESCU

    2017-05-01

    Full Text Available Public services decentralization is a major concern for policy makers when it comes to identifying the optimum model for reorganizing these services, in light of the 3Es of the organizational performance. The field experiences show that this process is different both from one state to another, and depending on the targeted activity sector, out of which the local transport service is distinguished as an ‘institutional orphan’. Taking into account one of the smart-cities’ recognition criteria, the urban mobility, the paper aims at substantiating that, despite the specific incrementalism of the public services decentralization, having a negative impact upon the services’ efficiency, in the case of local transport service, recognizing the right to mobility and the need to ensuring the environment for exercising this right, impels the ‘bureaucratic apparatus’ to accelerate and consolidate the decentralization of this service. Therefore, the paper puts forward a case study on the impact of decentralization upon the local public transport service of Bucharest municipality.

  5. Geometrical scaling vs factorizable eikonal models

    CERN Document Server

    Kiang, D

    1975-01-01

    Among various theoretical explanations or interpretations for the experimental data on the differential cross-sections of elastic proton-proton scattering at CERN ISR, the following two seem to be most remarkable: A) the excellent agreement of the Chou-Yang model prediction of d sigma /dt with data at square root s=53 GeV, B) the general manifestation of geometrical scaling (GS). The paper confronts GS with eikonal models with factorizable opaqueness, with special emphasis on the Chou-Yang model. (12 refs).

  6. Modeling of a completely on renewable energy based power generation in 2050 in autonomous, decentralized structures; Modellierung einer vollstaendig auf erneuerbaren Energien basierenden Stromerzeugung im Jahr 2050 in autarken, dezentralen Strukturen

    Energy Technology Data Exchange (ETDEWEB)

    Peter, Stefan

    2013-09-15

    The German Federal Environmental Agency (Umweltbundesamt, UBA) has developed three radically different scenarios of a future electricity supply entirely based on renewable sources in Germany by 2050. This study investigates the technical and ecological feasibility for one of these scenarios, the ''Local Energy Autarky'' scenario, by means of computer based simulation with a high spatial and temporal resolution. The scope of this scenario is restricted to small-scale decentralized energy systems which satisfy their own power demand without being connected with each other or with outside suppliers, i.e. without electricity imports. Relying only on locally available renewable energy sources to cover the electricity demand, makes electricity storage a necessity within the simulation model. The model itself consists of different modules representing electricity demand (e.g. for households, commerce and industry), power generation of different renewable technologies, and meteorological data, such as solar irradiation, wind speed, and outside temperatures. Various basic assumptions were made with regard to future developments such as energy efficiency. The simulations were applied exemplarily to a rural community with a low population density and a town district (high population and building density), each with and without trade/industry and each at a location in northern and in southern Germany, which are representative of the different meteorological conditions affecting the power generation from renewable sources such as wind and solar. Several variations were applied to the system, e.g. with regard to the share of electricity powered private vehicles or the installed generation capacities per technology. The simulation results show that the electricity demand of private households plus the demand for a complete shift to (private) e-mobility can be covered by the assumed locally available potentials for photovoltaics and wind energy, but only for

  7. Probabilistic, meso-scale flood loss modelling

    Science.gov (United States)

    Kreibich, Heidi; Botto, Anna; Schröter, Kai; Merz, Bruno

    2016-04-01

    Flood risk analyses are an important basis for decisions on flood risk management and adaptation. However, such analyses are associated with significant uncertainty, even more if changes in risk due to global change are expected. Although uncertainty analysis and probabilistic approaches have received increased attention during the last years, they are still not standard practice for flood risk assessments and even more for flood loss modelling. State of the art in flood loss modelling is still the use of simple, deterministic approaches like stage-damage functions. Novel probabilistic, multi-variate flood loss models have been developed and validated on the micro-scale using a data-mining approach, namely bagging decision trees (Merz et al. 2013). In this presentation we demonstrate and evaluate the upscaling of the approach to the meso-scale, namely on the basis of land-use units. The model is applied in 19 municipalities which were affected during the 2002 flood by the River Mulde in Saxony, Germany (Botto et al. submitted). The application of bagging decision tree based loss models provide a probability distribution of estimated loss per municipality. Validation is undertaken on the one hand via a comparison with eight deterministic loss models including stage-damage functions as well as multi-variate models. On the other hand the results are compared with official loss data provided by the Saxon Relief Bank (SAB). The results show, that uncertainties of loss estimation remain high. Thus, the significant advantage of this probabilistic flood loss estimation approach is that it inherently provides quantitative information about the uncertainty of the prediction. References: Merz, B.; Kreibich, H.; Lall, U. (2013): Multi-variate flood damage assessment: a tree-based data-mining approach. NHESS, 13(1), 53-64. Botto A, Kreibich H, Merz B, Schröter K (submitted) Probabilistic, multi-variable flood loss modelling on the meso-scale with BT-FLEMO. Risk Analysis.

  8. Drift-Scale THC Seepage Model

    Energy Technology Data Exchange (ETDEWEB)

    C.R. Bryan

    2005-02-17

    The purpose of this report (REV04) is to document the thermal-hydrologic-chemical (THC) seepage model, which simulates the composition of waters that could potentially seep into emplacement drifts, and the composition of the gas phase. The THC seepage model is processed and abstracted for use in the total system performance assessment (TSPA) for the license application (LA). This report has been developed in accordance with ''Technical Work Plan for: Near-Field Environment and Transport: Coupled Processes (Mountain-Scale TH/THC/THM, Drift-Scale THC Seepage, and Post-Processing Analysis for THC Seepage) Report Integration'' (BSC 2005 [DIRS 172761]). The technical work plan (TWP) describes planning information pertaining to the technical scope, content, and management of this report. The plan for validation of the models documented in this report is given in Section 2.2.2, ''Model Validation for the DS THC Seepage Model,'' of the TWP. The TWP (Section 3.2.2) identifies Acceptance Criteria 1 to 4 for ''Quantity and Chemistry of Water Contacting Engineered Barriers and Waste Forms'' (NRC 2003 [DIRS 163274]) as being applicable to this report; however, in variance to the TWP, Acceptance Criterion 5 has also been determined to be applicable, and is addressed, along with the other Acceptance Criteria, in Section 4.2 of this report. Also, three FEPS not listed in the TWP (2.2.10.01.0A, 2.2.10.06.0A, and 2.2.11.02.0A) are partially addressed in this report, and have been added to the list of excluded FEPS in Table 6.1-2. This report has been developed in accordance with LP-SIII.10Q-BSC, ''Models''. This report documents the THC seepage model and a derivative used for validation, the Drift Scale Test (DST) THC submodel. The THC seepage model is a drift-scale process model for predicting the composition of gas and water that could enter waste emplacement drifts and the effects of mineral

  9. Drift-Scale THC Seepage Model

    International Nuclear Information System (INIS)

    C.R. Bryan

    2005-01-01

    The purpose of this report (REV04) is to document the thermal-hydrologic-chemical (THC) seepage model, which simulates the composition of waters that could potentially seep into emplacement drifts, and the composition of the gas phase. The THC seepage model is processed and abstracted for use in the total system performance assessment (TSPA) for the license application (LA). This report has been developed in accordance with ''Technical Work Plan for: Near-Field Environment and Transport: Coupled Processes (Mountain-Scale TH/THC/THM, Drift-Scale THC Seepage, and Post-Processing Analysis for THC Seepage) Report Integration'' (BSC 2005 [DIRS 172761]). The technical work plan (TWP) describes planning information pertaining to the technical scope, content, and management of this report. The plan for validation of the models documented in this report is given in Section 2.2.2, ''Model Validation for the DS THC Seepage Model,'' of the TWP. The TWP (Section 3.2.2) identifies Acceptance Criteria 1 to 4 for ''Quantity and Chemistry of Water Contacting Engineered Barriers and Waste Forms'' (NRC 2003 [DIRS 163274]) as being applicable to this report; however, in variance to the TWP, Acceptance Criterion 5 has also been determined to be applicable, and is addressed, along with the other Acceptance Criteria, in Section 4.2 of this report. Also, three FEPS not listed in the TWP (2.2.10.01.0A, 2.2.10.06.0A, and 2.2.11.02.0A) are partially addressed in this report, and have been added to the list of excluded FEPS in Table 6.1-2. This report has been developed in accordance with LP-SIII.10Q-BSC, ''Models''. This report documents the THC seepage model and a derivative used for validation, the Drift Scale Test (DST) THC submodel. The THC seepage model is a drift-scale process model for predicting the composition of gas and water that could enter waste emplacement drifts and the effects of mineral alteration on flow in rocks surrounding drifts. The DST THC submodel uses a drift-scale

  10. Scale Model Thruster Acoustic Measurement Results

    Science.gov (United States)

    Vargas, Magda; Kenny, R. Jeremy

    2013-01-01

    The Space Launch System (SLS) Scale Model Acoustic Test (SMAT) is a 5% scale representation of the SLS vehicle, mobile launcher, tower, and launch pad trench. The SLS launch propulsion system will be comprised of the Rocket Assisted Take-Off (RATO) motors representing the solid boosters and 4 Gas Hydrogen (GH2) thrusters representing the core engines. The GH2 thrusters were tested in a horizontal configuration in order to characterize their performance. In Phase 1, a single thruster was fired to determine the engine performance parameters necessary for scaling a single engine. A cluster configuration, consisting of the 4 thrusters, was tested in Phase 2 to integrate the system and determine their combined performance. Acoustic and overpressure data was collected during both test phases in order to characterize the system's acoustic performance. The results from the single thruster and 4- thuster system are discussed and compared.

  11. Introducing local property tax for fiscal decentralization and local authority autonomy

    Science.gov (United States)

    Dimopoulos, Thomas; Labropoulos, Tassos; Hadjimitsis, Diafantos G.

    2015-06-01

    Charles Tiebout (1956), in his work "A Pure Theory of Local Expenditures", provides a vision of the workings of the local public sector, acknowledging many similarities to the features of a competitive market, however omitting any references to local taxation. Contrary to other researchers' claim that the Tiebout model and the theory of fiscal decentralization are by no means synonymous, this paper aims to expand Tiebout's theory, by adding the local property tax in the context, introducing a fair, ad valorem property taxation system based on the automated assessment of the value of real estate properties within the boundaries of local authorities. Computer Assisted Mass Appraisal methodology integrated with Remote Sensing technology and GIS analysis is applied to local authorities' property registries and cadastral data, building a spatial relational database and providing data to be statistically processed through Multiple Regression Analysis modeling. The proposed scheme accomplishes economy of scale using CAMA procedures on one hand, but also succeeds in making local authorities self-sufficient through a decentralized, fair, locally calibrated property taxation model, providing rational income administration.

  12. Decentralization in Botswana: the reluctant process | Dipholo ...

    African Journals Online (AJOL)

    Botswana\\'s decentralization process has always been justified in terms of democracy and development. Consequently, the government has always argued that it is fully committed to decentralization in order to promote popular participation as well as facilitating sustainable rural development. Yet the government does not ...

  13. Decentralized control using compositional analysis techniques

    NARCIS (Netherlands)

    Kerber, F.; van der Schaft, A. J.

    2011-01-01

    Decentralized control strategies aim at achieving a global control target by means of distributed local controllers acting on individual subsystems of the overall plant. In this sense, decentralized control is a dual problem to compositional analysis where a global verification task is decomposed

  14. Policy Recommendations on Decentralization, Local Power and ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2010-12-22

    Policy Recommendations on Decentralization, Local Power and Women's Rights. December 22, 2010. Image. The present document comprises a set of policy recommendations that define a global agenda on gender and decentralization. It emerged from the analysis and experiences shared during the Conference and the ...

  15. What supervisors want to know about decentralization.

    Science.gov (United States)

    Boissoneau, R; Belton, P

    1991-06-01

    Many organizations in various industries have tended to move away from strict centralization, yet some centralization is still vital to top management. With 19 of the 22 executives interviewed favoring or implementing some form of decentralization, it is probable that traditionally centralized organizations will follow the trend and begin to decentralize their organizational structures. The incentives and advantages of decentralization are too attractive to ignore. Decentralization provides responsibility, clear objectives, accountability for results, and more efficient and effective decision making. However, one must remember that decentralization can be overextended and that centralization is still viable in certain functions. Finding the correct balance between control and autonomy is a key to decentralization. Too much control and too much autonomy are the primary reasons for decentralization failures. In today's changing, competitive environment, structures must be continuously redefined, with the goal of finding an optimal balance between centralization and decentralization. Organizations are cautioned not to seek out and install a single philosopher-king to impose unified direction, but to unify leadership goals, participation, style, and control to develop improved methods of making all responsible leaders of one mind about the organization's needs and goals.

  16. Decentralization or centralization: striking a balance.

    Science.gov (United States)

    Dirschel, K M

    1994-09-01

    An Executive Vice President for Nursing can provide the necessary link to meet diverse clinical demands when encountering centralization--decentralization decisions. Centralized communication links hospital departments giving nurses a unified voice. Decentralization acknowledges the need for diversity and achieves the right balance of uniformity through a responsive communications network.

  17. Decentralized energy: technology assessment and systems description. [Potential for implementation for years 2000 and 2025

    Energy Technology Data Exchange (ETDEWEB)

    Reckard, M K

    1979-06-01

    Decentralized energy systems and their characteristic features are examined in the report. These systems have been divided into six groups for the purpose of analysis: solar, wind, hydro, biomass, geothermal, and coproduction (total energy). The technical and economic potential for the implementation of these systems is discussed for the years 2000 and 2025. The results of a comparison of base-case and decentralized scenarios for the year 2000, using a computer systems model, are presented. Social and institutional factors are also addressed, both as motivations for and results of energy system decentralization. Appendices are included with more detailed technical information on each of the systems groups.

  18. Wage Dispersion and Decentralization of Wage Bargaining

    DEFF Research Database (Denmark)

    Dahl, Christian Møller; le Maire, Christian Daniel; Munch, Jakob R.

    2013-01-01

    This article studies how decentralization of wage bargaining from sector to firm level influences wage levels and wage dispersion. We use detailed panel data covering a period of decentralization in the Danish labor market. The decentralization process provides variation in the individual worker......'s wage-setting system that facilitates identification of the effects of decentralization. We find a wage premium associated with firm-level bargaining relative to sector-level bargaining and that the return to skills is higher under the more decentralized wage-setting systems. Using quantile regression......, we also find that wages are more dispersed under firm-level bargaining compared to more centralized wage-setting systems....

  19. Decentralized Procurement in Light of Strategic Inventories

    DEFF Research Database (Denmark)

    Frimor, Hans; Arya, Anil; Mittendorf, Brian

    2015-01-01

    The centralization versus decentralization choice is perhaps the quintessential organizational structure decision. In the operations realm, this choice is particularly critical when it comes to the procurement function. Why firms may opt to decentralize procurement has been often studied and conf......The centralization versus decentralization choice is perhaps the quintessential organizational structure decision. In the operations realm, this choice is particularly critical when it comes to the procurement function. Why firms may opt to decentralize procurement has been often studied...... and confirmed to be a multifaceted choice. This paper complements existing studies by detailing the trade-offs in the centralization versus decentralization decision in light of firm's decision to cede procurement choices to its individual devisions can help moderate inventory levels and provide a natural salve...

  20. Driving up Standards: Civil Service Management and Decentralization: Case Study of Uganda

    Directory of Open Access Journals (Sweden)

    Lazarus Nabaho

    2012-12-01

    Full Text Available There is a consensus that decentralization by devolution leads to improved service delivery, but debate on the appropriate type of personnel arrangements for delivering decentralized services is far from over. Put differently, the discourse on whether civil service management should be decentralized or devolved still rages on. Little wonder that countries which started off with decentralized civil service management models in the 1990s are currently centralizing some aspects of personnel management while others are having centralized and decentralized personnel arrangements operating side by side in sub-national governments. The paper argues that civil service management should be decentralized whenever a country chooses the path of decentralization by devolution. Using Uganda’s example, the paper highlights two major challenges of managing the civil service under separate personnel arrangements: civil service appointments devoid of merit, and the perennial failure to attract and retain qualified human resource. The paper presents proposals on how to ensure meritocracy in appointments and how to bolster attraction and retention of human capital in local governments.

  1. Decentralized Energy from Waste Systems

    Directory of Open Access Journals (Sweden)

    Blanca Antizar-Ladislao

    2010-01-01

    Full Text Available In the last five years or so, biofuels have been given notable consideration worldwide as an alternative to fossil fuels, due to their potential to reduce greenhouse gas emissions by partial replacement of oil as a transport fuel. The production of biofuels using a sustainable approach, should consider local production of biofuels, obtained from local feedstocks and adapted to the socio-economical and environmental characteristics of the particular region where they are developed. Thus, decentralized energy from waste systems will exploit local biomass to optimize their production and consumption. Waste streams such as agricultural and wood residues, municipal solid waste, vegetable oils, and algae residues can all be integrated in energy from waste systems. An integral optimization of decentralized energy from waste systems should not be based on the optimization of each single process, but the overall optimization of the whole process. This is by obtaining optimal energy and environmental benefits, as well as collateral beneficial co-products such as soil fertilizers which will result in a higher food crop production and carbon dioxide fixation which will abate climate change.

  2. Decentralized energy from waste systems

    International Nuclear Information System (INIS)

    Antizar-Ladislao, B.; Turrion-Gomez, J. L.

    2010-01-01

    In the last five years or so, biofuels have been given notable consideration worldwide as an alternative to fossil fuels, due to their potential to reduce greenhouse gas emissions by partial replacement of oil as a transport fuel. The production of biofuels using a sustainable approach, should consider local production of biofuels, obtained from local feedstocks and adapted to the socio-economical and environmental characteristics of the particular region where they are developed. Thus, decentralized energy from waste systems will exploit local biomass to optimize their production and consumption. Waste streams such as agricultural and wood residues, municipal solid waste, vegetable oils, and algae residues can all be integrated in energy from waste systems. An integral optimization of decentralized energy from waste systems should not be based on the optimization of each single process, but the overall optimization of the whole process. This is by obtaining optimal energy and environmental benefits, as well as collateral beneficial co-products such as soil fertilizers which will result in a higher food crop production and carbon dioxide fixation which will abate climate change. (author)

  3. Comparative LCA of decentralized wastewater treatment alternatives for non-potable urban reuse.

    Science.gov (United States)

    Opher, Tamar; Friedler, Eran

    2016-11-01

    Municipal wastewater (WW) effluent represents a reliable and significant source for reclaimed water, very much needed nowadays. Water reclamation and reuse has become an attractive option for conserving and extending available water sources. The decentralized approach to domestic WW treatment benefits from the advantages of source separation, which makes available simple small-scale systems and on-site reuse, which can be constructed on a short time schedule and occasionally upgraded with new technological developments. In this study we perform a Life Cycle Assessment to compare between the environmental impacts of four alternatives for a hypothetical city's water-wastewater service system. The baseline alternative is the most common, centralized approach for WW treatment, in which WW is conveyed to and treated in a large wastewater treatment plant (WWTP) and is then discharged to a stream. The three alternatives represent different scales of distribution of the WW treatment phase, along with urban irrigation and domestic non-potable water reuse (toilet flushing). The first alternative includes centralized treatment at a WWTP, with part of the reclaimed WW (RWW) supplied back to the urban consumers. The second and third alternatives implement de-centralized greywater (GW) treatment with local reuse, one at cluster level (320 households) and one at building level (40 households). Life cycle impact assessment results show a consistent disadvantage of the prevailing centralized approach under local conditions in Israel, where seawater desalination is the marginal source of water supply. The alternative of source separation and GW reuse at cluster level seems to be the most preferable one, though its environmental performance is only slightly better than GW reuse at building level. Centralized WW treatment with urban reuse of WWTP effluents is not advantageous over decentralized treatment of GW because the supply of RWW back to consumers is very costly in materials and

  4. 1/3-scale model testing program

    International Nuclear Information System (INIS)

    Yoshimura, H.R.; Attaway, S.W.; Bronowski, D.R.; Uncapher, W.L.; Huerta, M.; Abbott, D.G.

    1989-01-01

    This paper describes the drop testing of a one-third scale model transport cask system. Two casks were supplied by Transnuclear, Inc. (TN) to demonstrate dual purpose shipping/storage casks. These casks will be used to ship spent fuel from DOEs West Valley demonstration project in New York to the Idaho National Engineering Laboratory (INEL) for long term spent fuel dry storage demonstration. As part of the certification process, one-third scale model tests were performed to obtain experimental data. Two 9-m (30-ft) drop tests were conducted on a mass model of the cask body and scaled balsa and redwood filled impact limiters. In the first test, the cask system was tested in an end-on configuration. In the second test, the system was tested in a slap-down configuration where the axis of the cask was oriented at a 10 degree angle with the horizontal. Slap-down occurs for shallow angle drops where the primary impact at one end of the cask is followed by a secondary impact at the other end. The objectives of the testing program were to (1) obtain deceleration and displacement information for the cask and impact limiter system, (2) obtain dynamic force-displacement data for the impact limiters, (3) verify the integrity of the impact limiter retention system, and (4) examine the crush behavior of the limiters. This paper describes both test results in terms of measured deceleration, post test deformation measurements, and the general structural response of the system

  5. Genome scale metabolic modeling of cancer

    DEFF Research Database (Denmark)

    Nilsson, Avlant; Nielsen, Jens

    2017-01-01

    of metabolism which allows simulation and hypotheses testing of metabolic strategies. It has successfully been applied to many microorganisms and is now used to study cancer metabolism. Generic models of human metabolism have been reconstructed based on the existence of metabolic genes in the human genome......Cancer cells reprogram metabolism to support rapid proliferation and survival. Energy metabolism is particularly important for growth and genes encoding enzymes involved in energy metabolism are frequently altered in cancer cells. A genome scale metabolic model (GEM) is a mathematical formalization...

  6. Decentralized energy planning and consensus in energy policy

    Energy Technology Data Exchange (ETDEWEB)

    Wilbanks, T. J.

    1980-05-02

    This paper explores the following three propositions and their relationships: (1) that, in our pluralistic policymaking environment, we cannot solve our nation's energy problems unless we can reach agreement among a diverse group of interested parties about specific actions; (2) that, short of a manifest emergency, such a consensus is difficult to reach unless the scale of the decision-making unit is relatively small; and therefore (3) that one of the keys to an effective energy policy in the United states is to rely heavily on local and regional energy planning and decision-making. First, the paper reviews our problem of irresolution and its roots, and it summaries the policy options for resolving it. Then it explores one of those options, decentralized planning, in a little more detail. Finally, it offers some speculations about the viability of a decentralized approach to energy planninng.

  7. Decentralized substations for low-temperature district heating with no Legionella risk, and low return temperatures

    International Nuclear Information System (INIS)

    Yang, Xiaochen; Li, Hongwei; Svendsen, Svend

    2016-01-01

    To improve energy efficiency and give more access to renewable energy sources, low-temperature district heating (LTDH) is a promising concept to be realized in the future. However, concern about Legionella proliferation restricts applying low-temperature district heating in conventional systems with domestic hot water (DHW) circulation. In this study, a system with decentralized substations was analysed as a solution to this problem. Furthermore, a modification for the decentralized substation system were proposed in order to reduce the average return temperature. Models of conventional system with medium-temperature district heating, decentralized substation system with LTDH, and innovative decentralized substation system with LTDH were built based on the information of a case building. The annual distribution heat loss and the operating costs of the three scenarios were calculated and compared. From the results, realizing LTDH by the decentralized substation unit, 30% of the annual distribution heat loss inside the building can be saved compared to a conventional system with medium-temperature district heating. Replacing the bypass pipe with an in-line supply pipe and a heat pump, the innovative decentralized substation system can reduce distribution heat loss by 39% compared to the conventional system and by 12% compared to the normal decentralized substation system with bypass. - Highlights: • The system of decentralized substations can realize low-temperature district heating without running the risk of Legionella. • Decentralized substations help reduce the distribution heat loss inside the building compared to conventional system. • A new concept that can reduce the return temperature for district heating is proposed and analysed.

  8. Large-scale multimedia modeling applications

    International Nuclear Information System (INIS)

    Droppo, J.G. Jr.; Buck, J.W.; Whelan, G.; Strenge, D.L.; Castleton, K.J.; Gelston, G.M.

    1995-08-01

    Over the past decade, the US Department of Energy (DOE) and other agencies have faced increasing scrutiny for a wide range of environmental issues related to past and current practices. A number of large-scale applications have been undertaken that required analysis of large numbers of potential environmental issues over a wide range of environmental conditions and contaminants. Several of these applications, referred to here as large-scale applications, have addressed long-term public health risks using a holistic approach for assessing impacts from potential waterborne and airborne transport pathways. Multimedia models such as the Multimedia Environmental Pollutant Assessment System (MEPAS) were designed for use in such applications. MEPAS integrates radioactive and hazardous contaminants impact computations for major exposure routes via air, surface water, ground water, and overland flow transport. A number of large-scale applications of MEPAS have been conducted to assess various endpoints for environmental and human health impacts. These applications are described in terms of lessons learned in the development of an effective approach for large-scale applications

  9. Aerosol numerical modelling at local scale

    International Nuclear Information System (INIS)

    Albriet, Bastien

    2007-01-01

    At local scale and in urban areas, an important part of particulate pollution is due to traffic. It contributes largely to the high number concentrations observed. Two aerosol sources are mainly linked to traffic. Primary emission of soot particles and secondary nanoparticle formation by nucleation. The emissions and mechanisms leading to the formation of such bimodal distribution are still badly understood nowadays. In this thesis, we try to provide an answer to this problematic by numerical modelling. The Modal Aerosol Model MAM is used, coupled with two 3D-codes: a CFD (Mercure Saturne) and a CTM (Polair3D). A sensitivity analysis is performed, at the border of a road but also in the first meters of an exhaust plume, to identify the role of each process involved and the sensitivity of different parameters used in the modelling. (author) [fr

  10. Bitcoin as a decentralized currency

    Directory of Open Access Journals (Sweden)

    Dinić Vladimir

    2014-01-01

    Full Text Available Bitcoin is the first decentralized peer-to-peer crypto-currency founded in 2009. Its main specificity is the fact that there is no issuer of this currency. On the other hand, the supply of this currency is software-programmed and limited. Among other things, its main features are relatively secure payments, low transaction costs, anonymity, inability of counterfeiting, irreversibility of transactions, but also extremely unstable exchange rate. Despite many advantages, the use of this currency is subject of numerous discussions, as this currency offers the possibility of performing various abuses and criminal activities. The future of this and other currencies in this regard depends on both security and privacy of these currencies, and legal regulation of such payments.

  11. Multi-scale Modelling of Segmentation

    DEFF Research Database (Denmark)

    Hartmann, Martin; Lartillot, Olivier; Toiviainen, Petri

    2016-01-01

    pieces. In a second experiment on non-real-time segmentation, musicians indicated boundaries and their strength for six examples. Kernel density estimation was used to develop multi-scale segmentation models. Contrary to previous research, no relationship was found between boundary strength and boundary......While listening to music, people often unwittingly break down musical pieces into constituent chunks such as verses and choruses. Music segmentation studies have suggested that some consensus regarding boundary perception exists, despite individual differences. However, neither the effects...

  12. Federalism and Decentralization of Education in Argentina. Unintended Consequences of Decentralization of Expenditures in a Federal Country.

    Science.gov (United States)

    Falleti, Tulia G.

    By analyzing the process of decentralization of education in Argentina, this paper complements the existing literature on decentralization and federalism in two ways: (1) it studies the impact of federal institutions on the origins and evolution of decentralization; and (2) it analyzes a case of decentralization of education that, in a way not…

  13. Coordinating decentralized optimization of truck and shovel mining operations

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, R.; Fraser Forbes, J. [Alberta Univ., Edmonton, AB (Canada). Dept. of Chemical and Materials Engineering; San Yip, W. [Suncor Energy, Fort McMurray, AB (Canada)

    2006-07-01

    Canada's oil sands contain the largest known reserve of oil in the world. Oil sands mining uses 3 functional processes, ore hauling, overburden removal and mechanical maintenance. The industry relies mainly on truck-and-shovel technology in its open-pit mining operations which contributes greatly to the overall mining operation cost. Coordination between operating units is crucial for achieving an enterprise-wide optimal operation level. Some of the challenges facing the industry include multiple or conflicting objectives such as minimizing the use of raw materials and energy while maximizing production. The large sets of constraints that define the feasible domain pose as challenge, as does the uncertainty in system parameters. One solution lies in assigning truck resources to various activities. This fully decentralized approach would treat the optimization of ore production, waste removal and equipment maintenance independently. It was emphasized that mine-wide optimal operation can only be achieved by coordinating ore hauling and overburden removal processes. For that reason, this presentation proposed a coordination approach for a decentralized optimization system. The approach is based on the Dantzig-Wolfe decomposition and auction-based methods that have been previously used to decompose large-scale optimization problems. The treatment of discrete variables and coordinator design was described and the method was illustrated with a simple truck and shovel mining simulation study. The approach can be applied to a wide range of applications such as coordinating decentralized optimal control systems and scheduling. 16 refs., 3 tabs., 2 figs.

  14. Blockchain technology and decentralized governance: Is the state still necessary?

    Directory of Open Access Journals (Sweden)

    Marcella Atzori

    2017-03-01

    Full Text Available The core technology of Bitcoin, the blockchain, has recently emerged as a disruptive innovation with a wide range of applications, potentially able to redesign our interactions in business, politics and society at large. Although scholarly interest in this subject is growing, a comprehensive analysis of blockchain applications from a political perspective is severely lacking to date. This paper aims to fill this gap and it discusses the key points of blockchain-based decentralized governance, which challenges to varying degrees the traditional mechanisms of State authority, citizenship and democracy. In particular, the paper verifies to which extent blockchain and decentralized platforms can be considered as hyper-political tools, capable to manage social interactions on large scale and dismiss traditional central authorities. The analysis highlights risks related to a dominant position of private powers in distributed ecosystems, which may lead to a general disempowerment of citizens and to the emergence of a stateless global society. While technological utopians urge the demise of any centralized institution, this paper advocates the role of the State as a necessary central point of coordination in society, showing that decentralization through algorithm-based consensus is an organizational theory, not a stand-alone political theory.

  15. Decentralization and financial autonomy: a challenge for local public authorities in the Republic of Moldova

    Directory of Open Access Journals (Sweden)

    Tatiana MANOLE

    2017-09-01

    Full Text Available This article reflects the decentralization process currently taking place in the Republic of Moldova. The purpose of the research is to acquaint readers with the fundamental concept of decentralization, with the areas of administrative decentralization, with the forms of manifestation of financial decentralization: fiscal decentralization and budget decentralization. The priorities of the decentralization process are identified.

  16. Computational Techniques for Model Predictive Control of Large-Scale Systems with Continuous-Valued and Discrete-Valued Inputs

    Directory of Open Access Journals (Sweden)

    Koichi Kobayashi

    2013-01-01

    Full Text Available We propose computational techniques for model predictive control of large-scale systems with both continuous-valued control inputs and discrete-valued control inputs, which are a class of hybrid systems. In the proposed method, we introduce the notion of virtual control inputs, which are obtained by relaxing discrete-valued control inputs to continuous variables. In online computation, first, we find continuous-valued control inputs and virtual control inputs minimizing a cost function. Next, using the obtained virtual control inputs, only discrete-valued control inputs at the current time are computed in each subsystem. In addition, we also discuss the effect of quantization errors. Finally, the effectiveness of the proposed method is shown by a numerical example. The proposed method enables us to reduce and decentralize the computation load.

  17. Molecular scale modeling of polymer imprint nanolithography.

    Science.gov (United States)

    Chandross, Michael; Grest, Gary S

    2012-01-10

    We present the results of large-scale molecular dynamics simulations of two different nanolithographic processes, step-flash imprint lithography (SFIL), and hot embossing. We insert rigid stamps into an entangled bead-spring polymer melt above the glass transition temperature. After equilibration, the polymer is then hardened in one of two ways, depending on the specific process to be modeled. For SFIL, we cross-link the polymer chains by introducing bonds between neighboring beads. To model hot embossing, we instead cool the melt to below the glass transition temperature. We then study the ability of these methods to retain features by removing the stamps, both with a zero-stress removal process in which stamp atoms are instantaneously deleted from the system as well as a more physical process in which the stamp is pulled from the hardened polymer at fixed velocity. We find that it is necessary to coat the stamp with an antifriction coating to achieve clean removal of the stamp. We further find that a high density of cross-links is necessary for good feature retention in the SFIL process. The hot embossing process results in good feature retention at all length scales studied as long as coated, low surface energy stamps are used.

  18. Decentralized Utilitarian Mechanisms for Scheduling Games

    NARCIS (Netherlands)

    Cole, R.; Correa, J.; Gkatzelis, V.; Mirrokni, V.; Olver, N.K.

    2015-01-01

    Game Theory and Mechanism Design are by now standard tools for studying and designing massive decentralized systems. Unfortunately, designing mechanisms that induce socially efficient outcomes often requires full information and prohibitively large computational resources. In this work we study

  19. The effects of fiscal decentralization in Albania

    Directory of Open Access Journals (Sweden)

    Dr.Sc. Blerta Dragusha

    2012-06-01

    Full Text Available “Basically decentralization is a democratic reform which seeks to transfer the political, administrative, financial and planning authority from central to local government. It seeks to develop civic participation, empowerment of local people in decision making process and to promote accountability and reliability: To achieve efficiency and effectiveness in the collection and management of resources and service delivery”1 The interest and curiosity of knowing how our country is doing in this process, still unfinished, served as a motivation forme to treat this topic: fiscal decentralization as a process of giving 'power' to local governments, not only in terms of rights deriving from this process but also on the responsibilities that come with it. Which are the stages before and after decentralization, and how has it affected the process in several key indicators? Is decentralization a good process only, or can any of its effects be seen as an disadvantage?

  20. Decentralization and the local development state

    DEFF Research Database (Denmark)

    Emmenegger, Rony Hugo

    2016-01-01

    This article explores the politics of decentralization and state-peasant encounters in rural Oromiya, Ethiopia. Breaking with a centralized past, the incumbent government of the Ethiopian People's Revolutionary Democratic Front (EPRDF) committed itself to a decentralization policy in the early 1990......s and has since then created a number of new sites for state-citizen interactions. In the context of electoral authoritarianism, however, decentralization has been interpreted as a means for the expansion of the party-state at the grass-roots level. Against this backdrop, this article attempts...... between the 2005 and 2010 elections. Based on ethnographic field research, the empirical case presented discloses that decentralization and state-led development serve the expansion of state power into rural areas, but that state authority is simultaneously constituted and undermined in the course...

  1. Making decentralization work for women in Uganda

    OpenAIRE

    Lakwo, A.

    2009-01-01

    This book is about engendering local governance. It explores the euphoria with which Uganda's decentralization policy took centre stage as a sufficient driver to engender local development responsiveness and accountability. Using a case study of AFARD in Nebbi district, it shows first that decentralized governance is gendered and technocratic as grassroots women's effective participation is lacking. Second, it shows that the insertion of women in local governance is merely a symbolic politica...

  2. Decentralized energy supply and electricity market structures

    OpenAIRE

    Weber, Christoph; Vogel, Philip

    2005-01-01

    Small decentralized power generation units (DG) are politically promoted because of their potential to reduce GHG-emissions and the existing dependency on fossil fuels. A long term goal of this promotion should be the creation of a level playing field for DG and conventional power generation. Due to the impact of DG on the electricity grid infrastructure, future regulation should consider the costs and benefits of the integration of decentralized energy generation units. Without an adequate c...

  3. Decentralized flight trajectory planning of multiple aircraft

    OpenAIRE

    Yokoyama, Nobuhiro; 横山 信宏

    2008-01-01

    Conventional decentralized algorithms for optimal trajectory planning tend to require prohibitive computational time as the number of aircraft increases. To overcome this drawback, this paper proposes a novel decentralized trajectory planning algorithm adopting a constraints decoupling approach for parallel optimization. The constraints decoupling approach is formulated as the path constraints of the real-time trajectory optimization problem based on nonlinear programming. Due to the parallel...

  4. Decentralized safety concept for closed-loop controlled intensive care.

    Science.gov (United States)

    Kühn, Jan; Brendle, Christian; Stollenwerk, André; Schweigler, Martin; Kowalewski, Stefan; Janisch, Thorsten; Rossaint, Rolf; Leonhardt, Steffen; Walter, Marian; Kopp, Rüdger

    2017-04-01

    This paper presents a decentralized safety concept for networked intensive care setups, for which a decentralized network of sensors and actuators is realized by embedded microcontroller nodes. It is evaluated for up to eleven medical devices in a setup for automated acute respiratory distress syndrome (ARDS) therapy. In this contribution we highlight a blood pump supervision as exemplary safety measure, which allows a reliable bubble detection in an extracorporeal blood circulation. The approach is validated with data of animal experiments including 35 bubbles with a size between 0.05 and 0.3 ml. All 18 bubbles with a size down to 0.15 ml are successfully detected. By using hidden Markov models (HMMs) as statistical method the number of necessary sensors can be reduced by two pressure sensors.

  5. On the random cascading model study of anomalous scaling in multiparticle production with continuously diminishing scale

    International Nuclear Information System (INIS)

    Liu Lianshou; Zhang Yang; Wu Yuanfang

    1996-01-01

    The anomalous scaling of factorial moments with continuously diminishing scale is studied using a random cascading model. It is shown that the model currently used have the property of anomalous scaling only for descrete values of elementary cell size. A revised model is proposed which can give good scaling property also for continuously varying scale. It turns out that the strip integral has good scaling property provided the integral regions are chosen correctly, and that this property is insensitive to the concrete way of self-similar subdivision of phase space in the models. (orig.)

  6. A high resolution global scale groundwater model

    Science.gov (United States)

    de Graaf, Inge; Sutanudjaja, Edwin; van Beek, Rens; Bierkens, Marc

    2014-05-01

    As the world's largest accessible source of freshwater, groundwater plays a vital role in satisfying the basic needs of human society. It serves as a primary source of drinking water and supplies water for agricultural and industrial activities. During times of drought, groundwater storage provides a large natural buffer against water shortage and sustains flows to rivers and wetlands, supporting ecosystem habitats and biodiversity. Yet, the current generation of global scale hydrological models (GHMs) do not include a groundwater flow component, although it is a crucial part of the hydrological cycle. Thus, a realistic physical representation of the groundwater system that allows for the simulation of groundwater head dynamics and lateral flows is essential for GHMs that increasingly run at finer resolution. In this study we present a global groundwater model with a resolution of 5 arc-minutes (approximately 10 km at the equator) using MODFLOW (McDonald and Harbaugh, 1988). With this global groundwater model we eventually intend to simulate the changes in the groundwater system over time that result from variations in recharge and abstraction. Aquifer schematization and properties of this groundwater model were developed from available global lithological maps and datasets (Dürr et al., 2005; Gleeson et al., 2010; Hartmann and Moosdorf, 2013), combined with our estimate of aquifer thickness for sedimentary basins. We forced the groundwater model with the output from the global hydrological model PCR-GLOBWB (van Beek et al., 2011), specifically the net groundwater recharge and average surface water levels derived from routed channel discharge. For the parameterization, we relied entirely on available global datasets and did not calibrate the model so that it can equally be expanded to data poor environments. Based on our sensitivity analysis, in which we run the model with various hydrogeological parameter settings, we observed that most variance in groundwater

  7. Integrated multi-scale modelling and simulation of nuclear fuels

    International Nuclear Information System (INIS)

    Valot, C.; Bertolus, M.; Masson, R.; Malerba, L.; Rachid, J.; Besmann, T.; Phillpot, S.; Stan, M.

    2015-01-01

    This chapter aims at discussing the objectives, implementation and integration of multi-scale modelling approaches applied to nuclear fuel materials. We will first show why the multi-scale modelling approach is required, due to the nature of the materials and by the phenomena involved under irradiation. We will then present the multiple facets of multi-scale modelling approach, while giving some recommendations with regard to its application. We will also show that multi-scale modelling must be coupled with appropriate multi-scale experiments and characterisation. Finally, we will demonstrate how multi-scale modelling can contribute to solving technology issues. (authors)

  8. Scaling and constitutive relationships in downcomer modeling

    International Nuclear Information System (INIS)

    Daly, B.J.; Harlow, F.H.

    1978-12-01

    Constitutive relationships to describe mass and momentum exchange in multiphase flow in a pressurized water reactor downcomer are presented. Momentum exchange between the phases is described by the product of the flux of momentum available for exchange and the effective area for interaction. The exchange of mass through condensation is assumed to occur along a distinct condensation boundary separating steam at saturation temperature from water in which the temperature falls off roughly linearly with distance from the boundary. Because of the abundance of nucleation sites in a typical churning flow in a downcomer, we propose an equilibrium evaporation process that produces sufficient steam per unit time to keep the water perpetually cooled to the saturation temperature. The transport equations, constitutive models, and boundary conditions used in the K-TIF numerical method are nondimensionalized to obtain scaling relationships for two-phase flow in the downcomer. The results indicate that, subject to idealized thermodynamic and hydraulic constraints, exact mathematical scaling can be achieved. Experiments are proposed to isolate the effects of parameters that contribute to mass, momentum, and energy exchange between the phases

  9. Cavitation erosion - scale effect and model investigations

    Science.gov (United States)

    Geiger, F.; Rutschmann, P.

    2015-12-01

    The experimental works presented in here contribute to the clarification of erosive effects of hydrodynamic cavitation. Comprehensive cavitation erosion test series were conducted for transient cloud cavitation in the shear layer of prismatic bodies. The erosion pattern and erosion rates were determined with a mineral based volume loss technique and with a metal based pit count system competitively. The results clarified the underlying scale effects and revealed a strong non-linear material dependency, which indicated significantly different damage processes for both material types. Furthermore, the size and dynamics of the cavitation clouds have been assessed by optical detection. The fluctuations of the cloud sizes showed a maximum value for those cavitation numbers related to maximum erosive aggressiveness. The finding suggests the suitability of a model approach which relates the erosion process to cavitation cloud dynamics. An enhanced experimental setup is projected to further clarify these issues.

  10. Reply to Comment on ‘Energy and air emission implications of a decentralized wastewater system’

    International Nuclear Information System (INIS)

    Shehabi, Arman; Stokes, Jennifer R; Horvath, Arpad

    2013-01-01

    Complementing centralized water-related infrastructure with decentralized facilities is being considered in some communities and a life-cycle perspective is needed for informed decision making. Our 2012 study presents a framework for analyzing the environmental effects of decentralized wastewater systems. While the analysis framework could be applied to cases with a variety of sizes, we evaluated two currently operating systems in California, one decentralized and one centralized plant with a much larger capacity. The disparate scales of the two plants represent an ‘off-the-grid’ suburban neighborhood-scale system compared with a similarly sized neighborhood connecting to an adjacent large centralized plant. Deciding whether or not to connect expanding developments to nearby centralized plants is a realistic scenario for future growth, making the treatment plants evaluated in our study a realistic choice for comparison. (reply)

  11. The contribution of fiscal/financial decentralization to the debt expansion of the local financing platform

    Science.gov (United States)

    Huayang, Yin; Di, Zhou; Bing, Cui

    2018-02-01

    Using soft budget theory to explore the formation mechanism and the deep institutional incentive of the local financing platform debt expansion from the perspective of fiscal / financial decentralization, construct theoretical framework which explain the expansion of local debt financing platform and conduct an empirical test, the results showed that the higher the degree of fiscal decentralization, fiscal autonomy as a soft constraint body of local government the stronger, local financing platform debt scale is greater; the higher the degree of financial decentralization, local government and financial institutions have the higher autonomy with respect to the central, local financing platform debt scale is bigger; financial synergy degree is stronger, local government financial mutual supervision prompted the local government debt more transparency, local debt financing platform size is smaller.

  12. Integration of decentralized electricity production

    International Nuclear Information System (INIS)

    Tomekova, A.

    2004-01-01

    The project SustelNet also deals with the possibilities of future development of DG sources. Within the project frame a quite general concept of the so-called 'equal field' for centralized and decentralized production was chosen for the better integration of DG. Its aim was to the achieve demanded level on the market in the future term (by 2020). Looking at the problem in the wider context means, that both forms of the production should be admitted on the market on the same conditions. The result of this project is a regulatory map, which actually serves as a definite regulatory strategy for more effective employment of DG sources. On the basis of the national regulatory strategies a proposition of regulatory map for EU will be launched, including some recommendations for European Commission. A few expert papers (scenario of proceeding, benchmarking, economical tools and criteria) are also output of this project. Five member states of the EU and four entering countries have been involved in this project. The final results of this procedure will be presented from April 2004 on international and national conferences, seminaries, or by means of other ways of publicity

  13. Decentralization and Change in Teaching Style in Sweden: The Emergence and Expansion of the "Working Team" (arbetslag) from 1960 to 1980

    OpenAIRE

    林, 寛平

    2014-01-01

    This paper discusses the change in teaching style in Sweden from 1960 to 1980 stemming from the decentralization reform in education. This discussion is important in two ways: to focus on the Swedish case as a suggestive model for Japan and to link decentralization as an administration reform with what happened in the classrooms.Decentralization is one of the key agendas in education reform in many countries, with Sweden having received much attention as a pioneer in the field. It is importan...

  14. Comparison Between Overtopping Discharge in Small and Large Scale Models

    DEFF Research Database (Denmark)

    Helgason, Einar; Burcharth, Hans F.

    2006-01-01

    The present paper presents overtopping measurements from small scale model test performed at the Haudraulic & Coastal Engineering Laboratory, Aalborg University, Denmark and large scale model tests performed at the Largde Wave Channel,Hannover, Germany. Comparison between results obtained from...... small and large scale model tests show no clear evidence of scale effects for overtopping above a threshold value. In the large scale model no overtopping was measured for waveheights below Hs = 0.5m as the water sunk into the voids between the stones on the crest. For low overtopping scale effects...

  15. Subsecond Tsunamis and Delays in Decentralized Electronic Systems

    Directory of Open Access Journals (Sweden)

    Pedro D. Manrique

    2017-10-01

    Full Text Available Driven by technological advances and economic gain, society’s electronic systems are becoming larger, faster, more decentralized and autonomous, and yet with increasing global reach. A prime example are the networks of financial markets which—in contrast to popular perception—are largely all-electronic and decentralized with no top-down real-time controller. This prototypical system generates complex subsecond dynamics that emerge from a decentralized network comprising heterogeneous hardware and software components, communications links, and a diverse ecology of trading algorithms that operate and compete within this all-electronics environment. Indeed, these same technological and economic drivers are likely to generate a similarly competitive all-electronic ecology in a variety of future cyberphysical domains such as e-commerce, defense and the transportation system, including the likely appearance of large numbers of autonomous vehicles on the streets of many cities. Hence there is an urgent need to deepen our understanding of stability, safety and security across a wide range of ultrafast, large, decentralized all-electronic systems—in short, society will eventually need to understand what extreme behaviors can occur, why, and what might be the impact of both intentional and unintentional system perturbations. Here we set out a framework for addressing this issue, using a generic model of heterogeneous, adaptive, autonomous components where each has a realistic limit on the amount of information and processing power available to it. We focus on the specific impact of delayed information, possibly through an accidental shift in the latency of information transmission, or an intentional attack from the outside. While much remains to be done in terms of developing formal mathematical results for this system, our preliminary results indicate the type of impact that can occur and the structure of a mathematical theory which may

  16. Game-Based Virtual Worlds as Decentralized Virtual Activity Systems

    Science.gov (United States)

    Scacchi, Walt

    There is widespread interest in the development and use of decentralized systems and virtual world environments as possible new places for engaging in collaborative work activities. Similarly, there is widespread interest in stimulating new technological innovations that enable people to come together through social networking, file/media sharing, and networked multi-player computer game play. A decentralized virtual activity system (DVAS) is a networked computer supported work/play system whose elements and social activities can be both virtual and decentralized (Scacchi et al. 2008b). Massively multi-player online games (MMOGs) such as World of Warcraft and online virtual worlds such as Second Life are each popular examples of a DVAS. Furthermore, these systems are beginning to be used for research, deve-lopment, and education activities in different science, technology, and engineering domains (Bainbridge 2007, Bohannon et al. 2009; Rieber 2005; Scacchi and Adams 2007; Shaffer 2006), which are also of interest here. This chapter explores two case studies of DVASs developed at the University of California at Irvine that employ game-based virtual worlds to support collaborative work/play activities in different settings. The settings include those that model and simulate practical or imaginative physical worlds in different domains of science, technology, or engineering through alternative virtual worlds where players/workers engage in different kinds of quests or quest-like workflows (Jakobsson 2006).

  17. Simultaneous nested modeling from the synoptic scale to the LES scale for wind energy applications

    DEFF Research Database (Denmark)

    Liu, Yubao; Warner, Tom; Liu, Yuewei

    2011-01-01

    This paper describes an advanced multi-scale weather modeling system, WRF–RTFDDA–LES, designed to simulate synoptic scale (~2000 km) to small- and micro-scale (~100 m) circulations of real weather in wind farms on simultaneous nested grids. This modeling system is built upon the National Center f...

  18. ADRES : autonomous decentralized regenerative energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Brauner, G.; Einfalt, A.; Leitinger, C.; Tiefgraber, D. [Vienna Univ. of Technology (Austria)

    2007-07-01

    The autonomous decentralized regenerative energy systems (ADRES) research project demonstrates that decentralized network independent microgrids are the target power systems of the future. This paper presented a typical structure of a microgrid, demonstrating that all types of generation available can be integrated, from wind and small hydro to photovoltaic, fuel cell, biomass or biogas operated stirling motors and micro turbines. In grid connected operation the balancing energy and reactive power for voltage control will come from the public grid. If there is no interconnection to a superior grid, it will form an autonomous micro grid. In order to reduce peak power demand and base energy, autonomous microgrid technology requires highly efficient appliances. Otherwise large collector design, high storage and balancing generation capacities would be necessary, which would increase costs. End-use energy efficiency was discussed with reference to demand side management (DSM) strategies that match energy demand with actual supply in order to minimize the storage size needed. This paper also discussed network controls that comprise active and reactive power. Decentralized robust algorithms were investigated with reference to black-start ability and congestion management features. It was concluded that the trend to develop small decentralized grids in parallel to existing large systems will improve security of supply and reduce greenhouse gas emissions. Decentralized grids will also increase energy efficiency because regenerative energy will be used where it is collected in the form of electricity and heat, thus avoiding transport and the extension of transmission lines. Decentralized energy technology is now becoming more economic by efficient and economic mass production of components. Although decentralized energy technology requires energy automation, computer intelligence is becoming increasingly cost efficient. 2 refs., 4 figs.

  19. Models of Small-Scale Patchiness

    Science.gov (United States)

    McGillicuddy, D. J.

    2001-01-01

    Patchiness is perhaps the most salient characteristic of plankton populations in the ocean. The scale of this heterogeneity spans many orders of magnitude in its spatial extent, ranging from planetary down to microscale. It has been argued that patchiness plays a fundamental role in the functioning of marine ecosystems, insofar as the mean conditions may not reflect the environment to which organisms are adapted. Understanding the nature of this patchiness is thus one of the major challenges of oceanographic ecology. The patchiness problem is fundamentally one of physical-biological-chemical interactions. This interconnection arises from three basic sources: (1) ocean currents continually redistribute dissolved and suspended constituents by advection; (2) space-time fluctuations in the flows themselves impact biological and chemical processes, and (3) organisms are capable of directed motion through the water. This tripartite linkage poses a difficult challenge to understanding oceanic ecosystems: differentiation between the three sources of variability requires accurate assessment of property distributions in space and time, in addition to detailed knowledge of organismal repertoires and the processes by which ambient conditions control the rates of biological and chemical reactions. Various methods of observing the ocean tend to lie parallel to the axes of the space/time domain in which these physical-biological-chemical interactions take place. Given that a purely observational approach to the patchiness problem is not tractable with finite resources, the coupling of models with observations offers an alternative which provides a context for synthesis of sparse data with articulations of fundamental principles assumed to govern functionality of the system. In a sense, models can be used to fill the gaps in the space/time domain, yielding a framework for exploring the controls on spatially and temporally intermittent processes. The following discussion highlights

  20. Large scale injection test (LASGIT) modelling

    International Nuclear Information System (INIS)

    Arnedo, D.; Olivella, S.; Alonso, E.E.

    2010-01-01

    Document available in extended abstract form only. With the objective of understanding the gas flow processes through clay barriers in schemes of radioactive waste disposal, the Lasgit in situ experiment was planned and is currently in progress. The modelling of the experiment will permit to better understand of the responses, to confirm hypothesis of mechanisms and processes and to learn in order to design future experiments. The experiment and modelling activities are included in the project FORGE (FP7). The in situ large scale injection test Lasgit is currently being performed at the Aespoe Hard Rock Laboratory by SKB and BGS. An schematic layout of the test is shown. The deposition hole follows the KBS3 scheme. A copper canister is installed in the axe of the deposition hole, surrounded by blocks of highly compacted MX-80 bentonite. A concrete plug is placed at the top of the buffer. A metallic lid anchored to the surrounding host rock is included in order to prevent vertical movements of the whole system during gas injection stages (high gas injection pressures are expected to be reached). Hydration of the buffer material is achieved by injecting water through filter mats, two placed at the rock walls and two at the interfaces between bentonite blocks. Water is also injected through the 12 canister filters. Gas injection stages are performed injecting gas to some of the canister injection filters. Since the water pressure and the stresses (swelling pressure development) will be high during gas injection, it is necessary to inject at high gas pressures. This implies mechanical couplings as gas penetrates after the gas entry pressure is achieved and may produce deformations which in turn lead to permeability increments. A 3D hydro-mechanical numerical model of the test using CODE-BRIGHT is presented. The domain considered for the modelling is shown. The materials considered in the simulation are the MX-80 bentonite blocks (cylinders and rings), the concrete plug

  1. Modeling of micro-scale thermoacoustics

    Energy Technology Data Exchange (ETDEWEB)

    Offner, Avshalom [The Nancy and Stephen Grand Technion Energy Program, Technion-Israel Institute of Technology, Haifa 32000 (Israel); Department of Civil and Environmental Engineering, Technion-Israel Institute of Technology, Haifa 32000 (Israel); Ramon, Guy Z., E-mail: ramong@technion.ac.il [Department of Civil and Environmental Engineering, Technion-Israel Institute of Technology, Haifa 32000 (Israel)

    2016-05-02

    Thermoacoustic phenomena, that is, onset of self-sustained oscillations or time-averaged fluxes in a sound wave, may be harnessed as efficient and robust heat transfer devices. Specifically, miniaturization of such devices holds great promise for cooling of electronics. At the required small dimensions, it is expected that non-negligible slip effects exist at the solid surface of the “stack”-a porous matrix, which is used for maintaining the correct temporal phasing of the heat transfer between the solid and oscillating gas. Here, we develop theoretical models for thermoacoustic engines and heat pumps that account for slip, within the standing-wave approximation. Stability curves for engines with both no-slip and slip boundary conditions were calculated; the slip boundary condition curve exhibits a lower temperature difference compared with the no slip curve for resonance frequencies that characterize micro-scale devices. Maximum achievable temperature differences across the stack of a heat pump were also calculated. For this case, slip conditions are detrimental and such a heat pump would maintain a lower temperature difference compared to larger devices, where slip effects are negligible.

  2. Modeling of micro-scale thermoacoustics

    International Nuclear Information System (INIS)

    Offner, Avshalom; Ramon, Guy Z.

    2016-01-01

    Thermoacoustic phenomena, that is, onset of self-sustained oscillations or time-averaged fluxes in a sound wave, may be harnessed as efficient and robust heat transfer devices. Specifically, miniaturization of such devices holds great promise for cooling of electronics. At the required small dimensions, it is expected that non-negligible slip effects exist at the solid surface of the “stack”-a porous matrix, which is used for maintaining the correct temporal phasing of the heat transfer between the solid and oscillating gas. Here, we develop theoretical models for thermoacoustic engines and heat pumps that account for slip, within the standing-wave approximation. Stability curves for engines with both no-slip and slip boundary conditions were calculated; the slip boundary condition curve exhibits a lower temperature difference compared with the no slip curve for resonance frequencies that characterize micro-scale devices. Maximum achievable temperature differences across the stack of a heat pump were also calculated. For this case, slip conditions are detrimental and such a heat pump would maintain a lower temperature difference compared to larger devices, where slip effects are negligible.

  3. Sustainability evaluation of decentralized electricity generation

    International Nuclear Information System (INIS)

    Karger, Cornelia R.; Hennings, Wilfried

    2009-01-01

    Decentralized power generation is gaining significance in liberalized electricity markets. An increasing decentralization of power supply is expected to make a particular contribution to climate protection. This article investigates the advantages and disadvantages of decentralized electricity generation according to the overall concept of sustainable development. On the basis of a hierarchically structured set of sustainability criteria, four future scenarios for Germany are assessed, all of which describe different concepts of electricity supply in the context of the corresponding social and economic developments. The scenarios are developed in an explorative way according to the scenario method and the sustainability criteria are established by a discursive method with societal actors. The evaluation is carried out by scientific experts. By applying an expanded analytic hierarchy process (AHP), a multicriteria evaluation is conducted that identifies dissent among the experts. The results demonstrate that decentralized electricity generation can contribute to climate protection. The extent to which it simultaneously guarantees security of supply is still a matter of controversy. However, experts agree that technical and economic boundary conditions are of major importance in this field. In the final section, the article discusses the method employed here as well as implications for future decentralized energy supply. (author)

  4. Multi-Scale Models for the Scale Interaction of Organized Tropical Convection

    Science.gov (United States)

    Yang, Qiu

    Assessing the upscale impact of organized tropical convection from small spatial and temporal scales is a research imperative, not only for having a better understanding of the multi-scale structures of dynamical and convective fields in the tropics, but also for eventually helping in the design of new parameterization strategies to improve the next-generation global climate models. Here self-consistent multi-scale models are derived systematically by following the multi-scale asymptotic methods and used to describe the hierarchical structures of tropical atmospheric flows. The advantages of using these multi-scale models lie in isolating the essential components of multi-scale interaction and providing assessment of the upscale impact of the small-scale fluctuations onto the large-scale mean flow through eddy flux divergences of momentum and temperature in a transparent fashion. Specifically, this thesis includes three research projects about multi-scale interaction of organized tropical convection, involving tropical flows at different scaling regimes and utilizing different multi-scale models correspondingly. Inspired by the observed variability of tropical convection on multiple temporal scales, including daily and intraseasonal time scales, the goal of the first project is to assess the intraseasonal impact of the diurnal cycle on the planetary-scale circulation such as the Hadley cell. As an extension of the first project, the goal of the second project is to assess the intraseasonal impact of the diurnal cycle over the Maritime Continent on the Madden-Julian Oscillation. In the third project, the goals are to simulate the baroclinic aspects of the ITCZ breakdown and assess its upscale impact on the planetary-scale circulation over the eastern Pacific. These simple multi-scale models should be useful to understand the scale interaction of organized tropical convection and help improve the parameterization of unresolved processes in global climate models.

  5. SDG and qualitative trend based model multiple scale validation

    Science.gov (United States)

    Gao, Dong; Xu, Xin; Yin, Jianjin; Zhang, Hongyu; Zhang, Beike

    2017-09-01

    Verification, Validation and Accreditation (VV&A) is key technology of simulation and modelling. For the traditional model validation methods, the completeness is weak; it is carried out in one scale; it depends on human experience. The SDG (Signed Directed Graph) and qualitative trend based multiple scale validation is proposed. First the SDG model is built and qualitative trends are added to the model. And then complete testing scenarios are produced by positive inference. The multiple scale validation is carried out by comparing the testing scenarios with outputs of simulation model in different scales. Finally, the effectiveness is proved by carrying out validation for a reactor model.

  6. Downscaling modelling system for multi-scale air quality forecasting

    Science.gov (United States)

    Nuterman, R.; Baklanov, A.; Mahura, A.; Amstrup, B.; Weismann, J.

    2010-09-01

    Urban modelling for real meteorological situations, in general, considers only a small part of the urban area in a micro-meteorological model, and urban heterogeneities outside a modelling domain affect micro-scale processes. Therefore, it is important to build a chain of models of different scales with nesting of higher resolution models into larger scale lower resolution models. Usually, the up-scaled city- or meso-scale models consider parameterisations of urban effects or statistical descriptions of the urban morphology, whereas the micro-scale (street canyon) models are obstacle-resolved and they consider a detailed geometry of the buildings and the urban canopy. The developed system consists of the meso-, urban- and street-scale models. First, it is the Numerical Weather Prediction (HIgh Resolution Limited Area Model) model combined with Atmospheric Chemistry Transport (the Comprehensive Air quality Model with extensions) model. Several levels of urban parameterisation are considered. They are chosen depending on selected scales and resolutions. For regional scale, the urban parameterisation is based on the roughness and flux corrections approach; for urban scale - building effects parameterisation. Modern methods of computational fluid dynamics allow solving environmental problems connected with atmospheric transport of pollutants within urban canopy in a presence of penetrable (vegetation) and impenetrable (buildings) obstacles. For local- and micro-scales nesting the Micro-scale Model for Urban Environment is applied. This is a comprehensive obstacle-resolved urban wind-flow and dispersion model based on the Reynolds averaged Navier-Stokes approach and several turbulent closures, i.e. k -ɛ linear eddy-viscosity model, k - ɛ non-linear eddy-viscosity model and Reynolds stress model. Boundary and initial conditions for the micro-scale model are used from the up-scaled models with corresponding interpolation conserving the mass. For the boundaries a

  7. Decentralized H-infinity control of complex systems with delayed feedback

    Czech Academy of Sciences Publication Activity Database

    Bakule, Lubomír; Rehák, Branislav; Papík, Martin

    2016-01-01

    Roč. 67, č. 1 (2016), s. 127-131 ISSN 0005-1098 R&D Projects: GA ČR GA13-02149S Institutional support: RVO:67985556 Keywords : decentralized control * H-infinity control * large-scale systems * Fault-tolerant systems Subject RIV: BC - Control Systems Theory Impact factor: 5.451, year: 2016

  8. Distribution of decentralized renewable energy resources

    International Nuclear Information System (INIS)

    Bal, J.L.; Benque, J.P.

    1996-01-01

    The existence of a great number of inhabitants without electricity, living in areas of low population density, with modest energy requirements and low income provides a major potential market for decentralized renewable energy sources. Ademe and EDF in 1993 made two agreements concerning the development of Renewable Energy Sources. The first aims at promoting their decentralized use in France in pertinent cases. The second agreement concerns other countries and has two ambitions: facilitate short-term developments and produce in the longer term a standardised proposal for decentralized energy production using Renewable Energy Sources to a considerable extent. These ideas are explained, and the principles behind the implementation of both Ademe-EDF agreements as well as their future prospects are described. (R.P.)

  9. Decentralization, Local Rights and the Construction of Women's ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Decentralization, Local Rights and the Construction of Women's Citizenship : a Comparative Study in Kenya, Tanzania and Uganda - Phase II. Kenya, Tanzania and Uganda have adopted new land laws, policies and institutional arrangements to accommodate decentralization of land administration and management.

  10. Influence of the Budgetary Decentralization on the Economic Growth of Regions of Ukraine: Statistical Estimation

    Directory of Open Access Journals (Sweden)

    Voznyak Halyna V.

    2017-06-01

    Full Text Available The aim of the article is to define, determine and analyze the interrelationships between the budgetary decentralization and the economic growth of regions of Ukraine under conditions of reforming the power and financial resources. A statistical estimation of the influence of the budgetary decentralization on the economic growth of regions of Ukraine for 2015-2016 is carried out. The application of the panel data modeling allowed to build econometric models that made it possible to determine the ambiguous nature of the budgetary decentralization and identify key factors of its influence. It is shown that in terms of the income and expenditures the budgetary decentralization is positively associated with the economic growth of regions of Ukraine during the chosen time range of the study. The dynamic growth of the own revenues of local budgets is not a catalyst for the economic development of the regions. A strong negative effect of transfers on the dependent variable is confirmed. Among the variables included in the model and additionally characterizing the budgetary decentralization, the single tax and subsidies for the socio-economic development of individual territories attract attention. As a result of the study, the author justifies the need to minimize the transfer dependence of the regions at a simultaneous increasing of their own revenue base with local taxes and fees serving as a reliable basis for a long-term planning and development.

  11. Verification of Simulation Results Using Scale Model Flight Test Trajectories

    National Research Council Canada - National Science Library

    Obermark, Jeff

    2004-01-01

    .... A second compromise scaling law was investigated as a possible improvement. For ejector-driven events at minimum sideslip, the most important variables for scale model construction are the mass moment of inertia and ejector...

  12. Decentralized supply of electricity is a favorable development. Analysis of system options and effects

    International Nuclear Information System (INIS)

    Faber, A.; Ros, J.; De Boer-Meulman, P.; In 't Groen, B.

    2010-01-01

    Decentralised electricity systems can provide a significant contribution to the development of environment-friendly techniques such as solar power and electric vehicles. However, there are also some obstacles and uncertainties. Not only does the balancing of supply and demand constitute an important challenge; the development of smart grids is also crucial to the improvement of reliability and system efficiency of the decentralized grids. Especially the distribution of investment costs is a decisive factor for the success rate of decentralized electricity systems. What is more, it is still uncertain whether an extensive decentralized system would have a higher score in cleanliness, affordability and reliability than a future central system. The system variants can be distinguished based on the deployment of six possible energy technologies for the future: PV (solar power), micro-CHP, small-scale wind energy in the built environment (urban wind), heat pumps, electric vehicles and air-conditioning. [nl

  13. Centralized vs. decentralized child mental health services.

    Science.gov (United States)

    Adams, M S

    1977-09-01

    One of the basic tenets of the Community Mental Health Center movement is that services should be provided in the consumers' community. Various centers across the country have attempted to do this in either a centralized or decentralized fashion. Historically, most health services have been provided centrally, a good example being the traditional general hospital with its centralized medical services. Over the years, some of these services have become decentralized to take the form of local health centers, health maintenance organizations, community clinics, etc, and now various large mental health centers are also being broken down into smaller community units. An example of each type of mental health facility is delineated here.

  14. Decentralizing decision making in modularization strategies

    DEFF Research Database (Denmark)

    Israelsen, Poul; Jørgensen, Brian

    2011-01-01

    which distorts the economic effects of modularization at the level of the individual product. This has the implication that decisions on modularization can only be made by top management if decision authority and relevant information are to be aligned. To overcome this problem, we suggest a solution...... that aligns the descriptions of the economic consequences of modularization at the project and portfolio level which makes it possible to decentralize decision making while making sure that local goals are congruent with the global ones in order to avoid suboptimal behaviour. Keywords: Modularization......; Accounting; Cost allocation; Decision rule; Decentralization...

  15. Near optimal decentralized H_inf control

    DEFF Research Database (Denmark)

    Stoustrup, J.; Niemann, Hans Henrik

    It is shown that foir a class of decentralized control problems there does not exist a sequence of controllers of bounded order which obtains near optimal control. Neither does there exist an infinity dimentional optimal controller. Using the insight of the line of proof of these results, a heuri......It is shown that foir a class of decentralized control problems there does not exist a sequence of controllers of bounded order which obtains near optimal control. Neither does there exist an infinity dimentional optimal controller. Using the insight of the line of proof of these results...

  16. Decentralized enforcement, sequential bargaining, and the clean development mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Hovi, Jon

    2001-07-01

    While there is a vast literature both on international bargaining and on how international agreements can be enforced, very little work has been done on how bargaining and enforcement interact. An important exception is Fearon (1998), who models international cooperation as a two-stage process in which the bargaining process is constrained by a need for decentralized enforcement (meaning that the agreement must be enforced by the parties themselves rather than a third party, such as a court). Using the Clean Development Mechanism as an example, the present paper proposes a different model of this kind of interaction. The model follows Fearon's in so far as we both use the infinitely repeated Prisoners' Dilemma to capture the enforcement phase of the game. However, while Fearon depicts the bargaining stage as a War of Attrition, the present model sees that stage as a sequential bargaining game of the Staahl-Rubinstein type. The implications of the present model are compared both to those of the Staahl-Rubinstein model and to those of the Fearon model. A surprising conclusion is that a need for decentralized enforcement tends to make the bargaining outcome more symmetrical than otherwise. Thus, the impact of bargaining power is actually smaller when the resulting agreement must be enforced by the parties themselves than it is if enforcement is taken care of by a third party. (author)

  17. Modelling across bioreactor scales: methods, challenges and limitations

    DEFF Research Database (Denmark)

    Gernaey, Krist

    that it is challenging and expensive to acquire experimental data of good quality that can be used for characterizing gradients occurring inside a large industrial scale bioreactor. But which model building methods are available? And how can one ensure that the parameters in such a model are properly estimated? And what......Scale-up and scale-down of bioreactors are very important in industrial biotechnology, especially with the currently available knowledge on the occurrence of gradients in industrial-scale bioreactors. Moreover, it becomes increasingly appealing to model such industrial scale systems, considering...

  18. Modeling Lactococcus lactis using a genome-scale flux model

    Directory of Open Access Journals (Sweden)

    Nielsen Jens

    2005-06-01

    Full Text Available Abstract Background Genome-scale flux models are useful tools to represent and analyze microbial metabolism. In this work we reconstructed the metabolic network of the lactic acid bacteria Lactococcus lactis and developed a genome-scale flux model able to simulate and analyze network capabilities and whole-cell function under aerobic and anaerobic continuous cultures. Flux balance analysis (FBA and minimization of metabolic adjustment (MOMA were used as modeling frameworks. Results The metabolic network was reconstructed using the annotated genome sequence from L. lactis ssp. lactis IL1403 together with physiological and biochemical information. The established network comprised a total of 621 reactions and 509 metabolites, representing the overall metabolism of L. lactis. Experimental data reported in the literature was used to fit the model to phenotypic observations. Regulatory constraints had to be included to simulate certain metabolic features, such as the shift from homo to heterolactic fermentation. A minimal medium for in silico growth was identified, indicating the requirement of four amino acids in addition to a sugar. Remarkably, de novo biosynthesis of four other amino acids was observed even when all amino acids were supplied, which is in good agreement with experimental observations. Additionally, enhanced metabolic engineering strategies for improved diacetyl producing strains were designed. Conclusion The L. lactis metabolic network can now be used for a better understanding of lactococcal metabolic capabilities and potential, for the design of enhanced metabolic engineering strategies and for integration with other types of 'omic' data, to assist in finding new information on cellular organization and function.

  19. Decentralization and Economic Growth per capita in Europe

    NARCIS (Netherlands)

    Crucq, Pieter; Hemminga, Hendrik-Jan

    2007-01-01

    In this paper the relationship between decentralization and economic growth is investigated. The focus is on decentralization from the national government to the highest substate level in a country, which we define as regional decentralization. Section 2 discusses the different dimensions of

  20. Model of cosmology and particle physics at an intermediate scale

    International Nuclear Information System (INIS)

    Bastero-Gil, M.; Di Clemente, V.; King, S. F.

    2005-01-01

    We propose a model of cosmology and particle physics in which all relevant scales arise in a natural way from an intermediate string scale. We are led to assign the string scale to the intermediate scale M * ∼10 13 GeV by four independent pieces of physics: electroweak symmetry breaking; the μ parameter; the axion scale; and the neutrino mass scale. The model involves hybrid inflation with the waterfall field N being responsible for generating the μ term, the right-handed neutrino mass scale, and the Peccei-Quinn symmetry breaking scale. The large scale structure of the Universe is generated by the lightest right-handed sneutrino playing the role of a coupled curvaton. We show that the correct curvature perturbations may be successfully generated providing the lightest right-handed neutrino is weakly coupled in the seesaw mechanism, consistent with sequential dominance

  1. Semi-decentralized Strategies in Structural Vibration Control

    Directory of Open Access Journals (Sweden)

    F. Palacios-Quiñonero

    2011-04-01

    Full Text Available In this work, the main ideas involved in the design of overlapping and multi-overlapping controllers via the Inclusion Principle are discussed and illustrated in the context of the Structural Vibration Control of tall buildings under seismic excitation. A detailed theoretical background on the Inclusion Principle and the design of overlapping controllers is provided. Overlapping and multi-overlapping LQR controllers are designed for a simplified five-story building model. Numerical simulations are conducted to asses the performance of the proposed semi-decentralized controllers with positive results.

  2. Metropolitan Schools: Administrative Decentralization vs. Community Control.

    Science.gov (United States)

    Ornstein, Allan C.

    This book is divided into four chapters. The first examines the concepts and issues related to understanding social systems and how the schools can be viewed as a social system. The differences between centralization and decentralization, as well as systems-analysis and management-control approaches are also explored. In the next chapter, we are…

  3. Quotas and Decentralization (Indonesia) | CRDI - Centre de ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Over the past decade, the Government of Indonesia has taken steps to enhance the participation of women in public office. One element of the strategy is decentralization, promoted under the slogan, "local autonomy for people empowerment and welfare." Support for gender mainstreaming was proclaimed and in 2003 an ...

  4. Decentralized forest governance in central Vietnam

    NARCIS (Netherlands)

    Tran Nam, T.; Burgers, P.P.M.

    2012-01-01

    A major challenge in decentralized forest governance in Vietnam is developing a mechanism that would support both reforestation and poverty reduction among people in rural communities. To help address this challenge, Forest Land Allocation (FLA) policies recognize local communities and individuals

  5. Making decentralization work for women in Uganda

    NARCIS (Netherlands)

    Lakwo, A.

    2009-01-01

    This book is about engendering local governance. It explores the euphoria with which Uganda's decentralization policy took centre stage as a sufficient driver to engender local development responsiveness and accountability. Using a case study of AFARD in Nebbi district, it shows first that

  6. Decentralized Development Planning and Fragmentation of ...

    African Journals Online (AJOL)

    Using the Greater Accra Metropolitan Area (GAMA) as a case study, this paper argues that the proliferation of autonomous local government areas within the context of urban sprawl and other challenges have inhibited metropolitan-wide development planning. Keywords: Decentralization; local government; urban growth; ...

  7. Promoting Research for Policymaking under Decentralization in ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Major reforms in governance carried out in Peru during the early 2000s saw the decentralization of functions and resources from the central government in Lima to elected regional governments. Today, regional governments account for the majority of public investment, but show limited capacity to cope with the ...

  8. Decentralized Development Planning and Fragmentation of ...

    African Journals Online (AJOL)

    Using the GAMA as a case study, this paper examines the proliferation of .... These spatial definitions give territorial meaning to decentralization as dis- ... Formulated and implemented under a military regime, the Provisional ..... increased to four in 2004 following the creation of new districts in the country, and as part of.

  9. Decentralized Networked Control of Building Structures

    Czech Academy of Sciences Publication Activity Database

    Bakule, Lubomír; Rehák, Branislav; Papík, Martin

    2016-01-01

    Roč. 31, č. 11 (2016), s. 871-886 ISSN 1093-9687 R&D Projects: GA ČR GA13-02149S Institutional support: RVO:67985556 Keywords : decentralized control * networked control * building structures Subject RIV: BC - Control Systems Theory Impact factor: 5.786, year: 2016

  10. Women's Political Representation and Participation in Decentralized ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Huairou Commission User

    facilitate people's participation in national development through ensuring sound local level politics. • RC evolved into local councils which then led to the implementation of decentralization through the local government act (1997). • This policy has provided opportunities for women to participate in local leadership from.

  11. Decentralized Reinforcement Learning of robot behaviors

    NARCIS (Netherlands)

    Leottau, David L.; Ruiz-del-Solar, Javier; Babuska, R.

    2018-01-01

    A multi-agent methodology is proposed for Decentralized Reinforcement Learning (DRL) of individual behaviors in problems where multi-dimensional action spaces are involved. When using this methodology, sub-tasks are learned in parallel by individual agents working toward a common goal. In

  12. Strategies for organizing training: centralized or decentralized

    International Nuclear Information System (INIS)

    Kanous, L.E.

    1979-01-01

    STudies were conducted in the Detroit Edison Company for the purpose of determining effectiveness of training. A systems approach from the corporate perspective was found to be needed and worthwhile. At the conclusion of these studies a decision was made to move in the direction of a centralized vs decentralized organizational strategy for training

  13. Decentralization and Living Conditions in the EU

    NARCIS (Netherlands)

    Vries, M.S. de; Goymen, K.; Sazak, O.

    2014-01-01

    This paper investigates the effects of decentralization on living conditions in core cities in the European Union. It uses data from the Urban Audit to investigate whether the level of local expenditures relative to central government expenditures has an impact on the subjective appreciation of

  14. Satellite Power System (SPS) centralization/decentralization

    Science.gov (United States)

    Naisbitt, J.

    1978-01-01

    The decentralization of government in the United States of America is described and its effect on the solution of energy problems is given. The human response to the introduction of new technologies is considered as well as the behavioral aspects of multiple options.

  15. Towards a Decentralized Magnetic Indoor Positioning System

    Science.gov (United States)

    Kasmi, Zakaria; Norrdine, Abdelmoumen; Blankenbach, Jörg

    2015-01-01

    Decentralized magnetic indoor localization is a sophisticated method for processing sampled magnetic data directly on a mobile station (MS), thereby decreasing or even avoiding the need for communication with the base station. In contrast to central-oriented positioning systems, which transmit raw data to a base station, decentralized indoor localization pushes application-level knowledge into the MS. A decentralized position solution has thus a strong feasibility to increase energy efficiency and to prolong the lifetime of the MS. In this article, we present a complete architecture and an implementation for a decentralized positioning system. Furthermore, we introduce a technique for the synchronization of the observed magnetic field on the MS with the artificially-generated magnetic field from the coils. Based on real-time clocks (RTCs) and a preemptive operating system, this method allows a stand-alone control of the coils and a proper assignment of the measured magnetic fields on the MS. A stand-alone control and synchronization of the coils and the MS have an exceptional potential to implement a positioning system without the need for wired or wireless communication and enable a deployment of applications for rescue scenarios, like localization of miners or firefighters. PMID:26690145

  16. Towards a Decentralized Magnetic Indoor Positioning System

    Directory of Open Access Journals (Sweden)

    Zakaria Kasmi

    2015-12-01

    Full Text Available Decentralized magnetic indoor localization is a sophisticated method for processing sampled magnetic data directly on a mobile station (MS, thereby decreasing or even avoiding the need for communication with the base station. In contrast to central-oriented positioning systems, which transmit raw data to a base station, decentralized indoor localization pushes application-level knowledge into the MS. A decentralized position solution has thus a strong feasibility to increase energy efficiency and to prolong the lifetime of the MS. In this article, we present a complete architecture and an implementation for a decentralized positioning system. Furthermore, we introduce a technique for the synchronization of the observed magnetic field on the MS with the artificially-generated magnetic field from the coils. Based on real-time clocks (RTCs and a preemptive operating system, this method allows a stand-alone control of the coils and a proper assignment of the measured magnetic fields on the MS. A stand-alone control and synchronization of the coils and the MS have an exceptional potential to implement a positioning system without the need for wired or wireless communication and enable a deployment of applications for rescue scenarios, like localization of miners or firefighters.

  17. Decentralized data fusion with inverse covariance intersection

    NARCIS (Netherlands)

    Noack, B.; Sijs, J.; Reinhardt, M.; Hanebeck, U.D.

    2017-01-01

    In distributed and decentralized state estimation systems, fusion methods are employed to systematically combine multiple estimates of the state into a single, more accurate estimate. An often encountered problem in the fusion process relates to unknown common information that is shared by the

  18. Decentralization Fails Women in Sudan | IDRC - International ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2010-11-05

    Nov 5, 2010 ... In Sudan, decentralization is a process that has occurred over time and is ... In northern Sudan, some women travel three days to reach the nearest hospital. ... Accord stipulate that basic education is free, “in real life, it is not.”.

  19. PeerMatcher: Decentralized Partnership Formation

    NARCIS (Netherlands)

    Bozdog, N.V.; Voulgaris, S.; Bal, H.E.; van Halteren, A.

    2015-01-01

    This paper presents PeerMatcher, a fully decentralized algorithm solving the k-clique matching problem. The aim of k-clique matching is to cluster a set of nodes having pairwise weights into k-size groups of maximal total weight. Since solving the problem requires exponential time, PeerMatcher

  20. Noise magnetic Barkahausen: modeling and scale

    International Nuclear Information System (INIS)

    Rodríguez-Pérez, Jorge L.; Pérez Benítez, José A.

    2008-01-01

    Noise magnetic Barkahausen of produces due to network defaults, and is reflected in abrupt changes that take place in the magnetization of the material in Studio. This fact presupposes a complexity, according to the various factors that influence its occurrence and internal changes in the system. A study of noise are used in three fundamental quantities: length the signal, the area under the curve and the energy of the signal; from these other quantities that are used often are defined: the square root mean (average-quadratic voltage) signal and the amplitude of the signal (maximum peak voltage). This form of investigate the phenomenon assumes a statistical analysis of the behaviour of the signal as a result of a set of changes that occur in the material, showing the complexity of the system and the importance of the laws of scale. This paper investigates the relationship between noise magnetic Barkahausen, laws of scale and complexity using structural steel ATSM 36 samples that have been subjected to mechanical deformations by traction and compression. For it's performed a statistical analysis to determine the complexity from the Test-appointment and reported the values of fundamental quantities and laws of scale for different deformation, resulting in the unit which shows the connection between the values of the voltage quadratic medium, the depth of the sample, the characteristics of the laws of scale and complexity: a pseudo random system.

  1. The role of decentralized systems in providing universal electricity access in Sub-Saharan Africa – A model-based approach

    NARCIS (Netherlands)

    Dagnachew, Anteneh G.; Lucas, Paul L.|info:eu-repo/dai/nl/272607444; Hof, Andries F.|info:eu-repo/dai/nl/240412397; Gernaat, David E.H.J.|info:eu-repo/dai/nl/372664636; de Boer, Harmen Sytze; van Vuuren, Detlef P.|info:eu-repo/dai/nl/11522016X

    2017-01-01

    Poverty and lack of access to electricity are highly correlated. In Sub-Saharan Africa, one of the poorest regions in the world, two in every three people have no access to electricity. This paper describes a purpose designed model to explore and project the development in the Sub-Saharan African

  2. Strategic and Tactical Design of Competing Decentralized Supply Chain Networks with Risk-Averse Participants for Markets with Uncertain Demand

    OpenAIRE

    Hafezalkotob, Ashkan; Makui, Ahmad; Sadjadi, Seyed Jafar

    2011-01-01

    An integrated equilibrium model for tactical decisions in network design is developed. We consider a decentralized supply chain network operating in markets under uncertain demands when there is a rival decentralized chain. The primary assumption is that two chains provide partial substitutable products to the markets, and markets' demands are affected by tactical decisions such as price, service level, and advertising expenditure. Each chain consists of one risk-averse manufacturer and a set...

  3. The Goddard multi-scale modeling system with unified physics

    Directory of Open Access Journals (Sweden)

    W.-K. Tao

    2009-08-01

    Full Text Available Recently, a multi-scale modeling system with unified physics was developed at NASA Goddard. It consists of (1 a cloud-resolving model (CRM, (2 a regional-scale model, the NASA unified Weather Research and Forecasting Model (WRF, and (3 a coupled CRM-GCM (general circulation model, known as the Goddard Multi-scale Modeling Framework or MMF. The same cloud-microphysical processes, long- and short-wave radiative transfer and land-surface processes are applied in all of the models to study explicit cloud-radiation and cloud-surface interactive processes in this multi-scale modeling system. This modeling system has been coupled with a multi-satellite simulator for comparison and validation with NASA high-resolution satellite data.

    This paper reviews the development and presents some applications of the multi-scale modeling system, including results from using the multi-scale modeling system to study the interactions between clouds, precipitation, and aerosols. In addition, use of the multi-satellite simulator to identify the strengths and weaknesses of the model-simulated precipitation processes will be discussed as well as future model developments and applications.

  4. Microphysics in Multi-scale Modeling System with Unified Physics

    Science.gov (United States)

    Tao, Wei-Kuo

    2012-01-01

    Recently, a multi-scale modeling system with unified physics was developed at NASA Goddard. It consists of (1) a cloud-resolving model (Goddard Cumulus Ensemble model, GCE model), (2) a regional scale model (a NASA unified weather research and forecast, WRF), (3) a coupled CRM and global model (Goddard Multi-scale Modeling Framework, MMF), and (4) a land modeling system. The same microphysical processes, long and short wave radiative transfer and land processes and the explicit cloud-radiation, and cloud-land surface interactive processes are applied in this multi-scale modeling system. This modeling system has been coupled with a multi-satellite simulator to use NASA high-resolution satellite data to identify the strengths and weaknesses of cloud and precipitation processes simulated by the model. In this talk, a review of developments and applications of the multi-scale modeling system will be presented. In particular, the microphysics development and its performance for the multi-scale modeling system will be presented.

  5. Performance Analysis of the Decentralized Eigendecomposition and ESPRIT Algorithm

    Science.gov (United States)

    Suleiman, Wassim; Pesavento, Marius; Zoubir, Abdelhak M.

    2016-05-01

    In this paper, we consider performance analysis of the decentralized power method for the eigendecomposition of the sample covariance matrix based on the averaging consensus protocol. An analytical expression of the second order statistics of the eigenvectors obtained from the decentralized power method which is required for computing the mean square error (MSE) of subspace-based estimators is presented. We show that the decentralized power method is not an asymptotically consistent estimator of the eigenvectors of the true measurement covariance matrix unless the averaging consensus protocol is carried out over an infinitely large number of iterations. Moreover, we introduce the decentralized ESPRIT algorithm which yields fully decentralized direction-of-arrival (DOA) estimates. Based on the performance analysis of the decentralized power method, we derive an analytical expression of the MSE of DOA estimators using the decentralized ESPRIT algorithm. The validity of our asymptotic results is demonstrated by simulations.

  6. Decentralization of Health System in Islamic Republic of Iran

    Directory of Open Access Journals (Sweden)

    MJ Kabir

    2008-10-01

    Full Text Available Decentralization is the process of dispersing decision-making closer to the point of peripheral area, service or action. Basically decentralized governance, if properly planned and implemented, offers important opportunities for enhanced human development. The studies about this issue in different countries show that most of the decentralizations have been implemented in European countries and in comparison, the Middle East countries have been utilized lower degrees of the decentralization process. In fact, decentralization in the health system is a policy pursued for a variety of purposes including; increase in service delivery effectiveness and equity, improving efficiency and quality, fairness of financial contribution and planning for choosing the most appropriate interventions for the health priorities in peripheral regions. To implement decentralized governance, there is a spectrum of different choices that the government should regulate their degrees. Providing an appropriate atmosphere for decentralization is essential, otherwise lack of planning and achievement can result in complications for the system.

  7. Scaling considerations for modeling the in situ vitrification process

    International Nuclear Information System (INIS)

    Langerman, M.A.; MacKinnon, R.J.

    1990-09-01

    Scaling relationships for modeling the in situ vitrification waste remediation process are documented based upon similarity considerations derived from fundamental principles. Requirements for maintaining temperature and electric potential field similarity between the model and the prototype are determined as well as requirements for maintaining similarity in off-gas generation rates. A scaling rationale for designing reduced-scale experiments is presented and the results are assessed numerically. 9 refs., 6 figs

  8. Using LISREL to Evaluate Measurement Models and Scale Reliability.

    Science.gov (United States)

    Fleishman, John; Benson, Jeri

    1987-01-01

    LISREL program was used to examine measurement model assumptions and to assess reliability of Coopersmith Self-Esteem Inventory for Children, Form B. Data on 722 third-sixth graders from over 70 schools in large urban school district were used. LISREL program assessed (1) nature of basic measurement model for scale, (2) scale invariance across…

  9. Coulomb-gas scaling, superfluid films, and the XY model

    International Nuclear Information System (INIS)

    Minnhagen, P.; Nylen, M.

    1985-01-01

    Coulomb-gas-scaling ideas are invoked as a link between the superfluid density of two-dimensional 4 He films and the XY model; the Coulomb-gas-scaling function epsilon(X) is extracted from experiments and is compared with Monte Carlo simulations of the XY model. The agreement is found to be excellent

  10. Decentralized production management: telecommunication and coordination schemes validation

    International Nuclear Information System (INIS)

    Caire, R.; Retiere, N.; Hadjsaid, N.

    2005-01-01

    Decentralized production development is a reality in the majority of the power networks all over the world. The deregulation of the market of energy, ecological constraints as well as the technological developments of small power production encourage this development. Distribution networks represent the portion of the power system where the development of this production is the most awaited. Some studies carried out on the interconnection of decentralized production on a large scale ratio have shown significant effects and impacts on operation of the entire electric system. Indeed, the entire distribution network is going to be deeply modified by the introduction of new functions of remote control, of specific architectures, of intelligent protection systems and of telecommunication and information technologies. With these new paradigms the ability of testing and simulating the Distribution Management Systems is more and more necessary. Also, this is a crucial requirement for new communication means in order to better define the new management strategies of the production units within the distribution networks. The aim of this paper is to present a new real time experimental bench able to validate control strategies and communication devices included in Distribution Management Systems (DMS). (authors)

  11. Shorter Decentralized Attribute-Based Encryption via Extended Dual System Groups

    Directory of Open Access Journals (Sweden)

    Jie Zhang

    2017-01-01

    Full Text Available Decentralized attribute-based encryption (ABE is a special form of multiauthority ABE systems, in which no central authority and global coordination are required other than creating the common reference parameters. In this paper, we propose a new decentralized ABE in prime-order groups by using extended dual system groups. We formulate some assumptions used to prove the security of our scheme. Our proposed scheme is fully secure under the standard k-Lin assumption in random oracle model and can support any monotone access structures. Compared with existing fully secure decentralized ABE systems, our construction has shorter ciphertexts and secret keys. Moreover, fast decryption is achieved in our system, in which ciphertexts can be decrypted with a constant number of pairings.

  12. Remote handling of decentralized power generation plants; Fernwirken von dezentralen Energieerzeugungsanlagen

    Energy Technology Data Exchange (ETDEWEB)

    Conrad, Michael [IDS GmbH, Ettlingen (Germany). Geschaeftsbereich Entwicklung-Prozessautomatisierung; Thomas, Ralf [IDS GmbH, Ettlingen (Germany). Bereich Business Development und Marketing

    2011-05-15

    The incresing number of decentral power generation systems requires new grid solutions, i.e. the so-called smart grids. One important function is the monitoring and control, e.g. of decentral PV, wind power and cogeneration systems. The data interfaces used are highly diverse and as a rule are taken from measuring and automation technology, i.e. they must be adapted to the data models and transmission procedures of remote control and guidance systems. A compact protocol gateway enables standardized control and diagnosis.

  13. Decentralizing the Team Station: Simulation before Reality as a Best-Practice Approach.

    Science.gov (United States)

    Charko, Jackie; Geertsen, Alice; O'Brien, Patrick; Rouse, Wendy; Shahid, Ammarah; Hardenne, Denise

    2016-01-01

    The purpose of this article is to share the logistical planning requirements and simulation experience of one Canadian hospital as it prepared its staff for the change from a centralized inpatient unit model to the decentralized design planned for its new community hospital. With the commitment and support of senior leadership, project management resources and clinical leads worked collaboratively to design a decentralized prototype in the form of a pod-style environment in the hospital's current setting. Critical success factors included engaging the right stakeholders, providing an opportunity to test new workflows and technology, creating a strong communication plan and building on lessons learned as subsequent pod prototypes are launched.

  14. Measurement and Modelling of Scaling Minerals

    DEFF Research Database (Denmark)

    Villafafila Garcia, Ada

    2005-01-01

    -liquid equilibrium of sulphate scaling minerals (SrSO4, BaSO4, CaSO4 and CaSO4•2H2O) at temperatures up to 300ºC and pressures up to 1000 bar is described in chapter 4. Results for the binary systems (M2+, )-H2O; the ternary systems (Na+, M2+, )-H2O, and (Na+, M2+, Cl-)-H2O; and the quaternary systems (Na+, M2+)(Cl......-, )-H2O, are presented. M2+ stands for Ba2+, Ca2+, or Sr2+. Chapter 5 is devoted to the correlation and prediction of vapour-liquid-solid equilibria for different carbonate systems causing scale problems (CaCO3, BaCO3, SrCO3, and MgCO3), covering the temperature range from 0 to 250ºC and pressures up......-NaCl-Na2SO4-H2O are given. M2+ stands for Ca2+, Mg2+, Ba2+, and Sr2+. This chapter also includes an analysis of the CaCO3-MgCO3-CO2-H2O system. Chapter 6 deals with the system NaCl-H2O. Available data for that system at high temperatures and/or pressures are addressed, and sodium chloride solubility...

  15. Macro scale models for freight railroad terminals.

    Science.gov (United States)

    2016-03-02

    The project has developed a yard capacity model for macro-level analysis. The study considers the detailed sequence and scheduling in classification yards and their impacts on yard capacities simulate typical freight railroad terminals, and statistic...

  16. Scaling of Precipitation Extremes Modelled by Generalized Pareto Distribution

    Science.gov (United States)

    Rajulapati, C. R.; Mujumdar, P. P.

    2017-12-01

    Precipitation extremes are often modelled with data from annual maximum series or peaks over threshold series. The Generalized Pareto Distribution (GPD) is commonly used to fit the peaks over threshold series. Scaling of precipitation extremes from larger time scales to smaller time scales when the extremes are modelled with the GPD is burdened with difficulties arising from varying thresholds for different durations. In this study, the scale invariance theory is used to develop a disaggregation model for precipitation extremes exceeding specified thresholds. A scaling relationship is developed for a range of thresholds obtained from a set of quantiles of non-zero precipitation of different durations. The GPD parameters and exceedance rate parameters are modelled by the Bayesian approach and the uncertainty in scaling exponent is quantified. A quantile based modification in the scaling relationship is proposed for obtaining the varying thresholds and exceedance rate parameters for shorter durations. The disaggregation model is applied to precipitation datasets of Berlin City, Germany and Bangalore City, India. From both the applications, it is observed that the uncertainty in the scaling exponent has a considerable effect on uncertainty in scaled parameters and return levels of shorter durations.

  17. Scale gauge symmetry and the standard model

    International Nuclear Information System (INIS)

    Sola, J.

    1990-01-01

    This paper speculates on a version of the standard model of the electroweak and strong interactions coupled to gravity and equipped with a spontaneously broken, anomalous, conformal gauge symmetry. The scalar sector is virtually absent in the minimal model but in the general case it shows up in the form of a nonlinear harmonic map Lagrangian. A Euclidean approach to the phenological constant problem is also addressed in this framework

  18. Large-scale modelling of neuronal systems

    International Nuclear Information System (INIS)

    Castellani, G.; Verondini, E.; Giampieri, E.; Bersani, F.; Remondini, D.; Milanesi, L.; Zironi, I.

    2009-01-01

    The brain is, without any doubt, the most, complex system of the human body. Its complexity is also due to the extremely high number of neurons, as well as the huge number of synapses connecting them. Each neuron is capable to perform complex tasks, like learning and memorizing a large class of patterns. The simulation of large neuronal systems is challenging for both technological and computational reasons, and can open new perspectives for the comprehension of brain functioning. A well-known and widely accepted model of bidirectional synaptic plasticity, the BCM model, is stated by a differential equation approach based on bistability and selectivity properties. We have modified the BCM model extending it from a single-neuron to a whole-network model. This new model is capable to generate interesting network topologies starting from a small number of local parameters, describing the interaction between incoming and outgoing links from each neuron. We have characterized this model in terms of complex network theory, showing how this, learning rule can be a support For network generation.

  19. Multi-scale modeling for sustainable chemical production.

    Science.gov (United States)

    Zhuang, Kai; Bakshi, Bhavik R; Herrgård, Markus J

    2013-09-01

    With recent advances in metabolic engineering, it is now technically possible to produce a wide portfolio of existing petrochemical products from biomass feedstock. In recent years, a number of modeling approaches have been developed to support the engineering and decision-making processes associated with the development and implementation of a sustainable biochemical industry. The temporal and spatial scales of modeling approaches for sustainable chemical production vary greatly, ranging from metabolic models that aid the design of fermentative microbial strains to material and monetary flow models that explore the ecological impacts of all economic activities. Research efforts that attempt to connect the models at different scales have been limited. Here, we review a number of existing modeling approaches and their applications at the scales of metabolism, bioreactor, overall process, chemical industry, economy, and ecosystem. In addition, we propose a multi-scale approach for integrating the existing models into a cohesive framework. The major benefit of this proposed framework is that the design and decision-making at each scale can be informed, guided, and constrained by simulations and predictions at every other scale. In addition, the development of this multi-scale framework would promote cohesive collaborations across multiple traditionally disconnected modeling disciplines to achieve sustainable chemical production. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. The use of scale models in impact testing

    International Nuclear Information System (INIS)

    Donelan, P.J.; Dowling, A.R.

    1985-01-01

    Theoretical analysis, component testing and model flask testing are employed to investigate the validity of scale models for demonstrating the behaviour of Magnox flasks under impact conditions. Model testing is shown to be a powerful and convenient tool provided adequate care is taken with detail design and manufacture of models and with experimental control. (author)

  1. Policies to Spur Energy Access. Executive Summary; Volume 1, Engaging the Private Sector in Expanding Access to Electricity; Volume 2, Case Studies to Public-Private Models to Finance Decentralized Electricity Access

    Energy Technology Data Exchange (ETDEWEB)

    Walters, Terri [National Renewable Energy Lab. (NREL), Golden, CO (United States); Rai, Neha [International Institute for Environment and Development (IIED), London (England); Esterly, Sean [National Renewable Energy Lab. (NREL), Golden, CO (United States); Cox, Sadie [National Renewable Energy Lab. (NREL), Golden, CO (United States); Reber, Tim [National Renewable Energy Lab. (NREL), Golden, CO (United States); Muzammil, Maliha [Univ. of Oxford (United Kingdom); Mahmood, Tasfiq [International Center for Climate Change and Development, Baridhara (Bangladesh); Kaur, Nanki [International Institute for Environment and Development (IIED), London (England); Tesfaye, Lidya [Echnoserve Consulting (Ethiopia); Mamuye, Simret [Echnoserve Consulting (Ethiopia); Knuckles, James [Univ. of London (England). Cass Business School; Morris, Ellen [Columbia Univ., New York, NY (United States); de Been, Merijn [Delft Univ. of Technology (Netherlands); Steinbach, Dave [International Institute for Environment and Development (IIED), London (England); Acharya, Sunil [Digo Bikas Inst. (Nepal); Chhetri, Raju Pandit [National Renewable Energy Lab. (NREL), Golden, CO (United States); Bhushal, Ramesh [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2015-09-01

    Government policy is one of the most important factors in engaging the private sector in providing universal access to electricity. In particular, the private sector is well positioned to provide decentralized electricity products and services. While policy uncertainty and regulatory barriers can keep enterprises and investors from engaging in the market, targeted policies can create opportunities to leverage private investment and skills to expand electricity access. However, creating a sustainable market requires policies beyond traditional electricity regulation. The report reviews the range of policy issues that impact the development and expansion of a market for decentralized electricity services from establishing an enabling policy environment to catalyzing finance, building human capacity, and integrating energy access with development programs. The case studies in this report show that robust policy frameworks--addressing a wide range of market issues--can lead to rapid transformation in energy access. The report highlights examples of these policies in action Bangladesh, Ethiopia, Mali, Mexico, and Nepal.

  2. Scale model helps Duke untie construction snags

    International Nuclear Information System (INIS)

    Anon.

    1977-01-01

    A nuclear power plant model, only 60 percent complete, has helped Duke Power identify over 150 major design interferences, which, when resolved, will help cut capital expense and eliminate scheduling problems that normally crop up as revisions are made during actual plant construction. The model has been used by construction, steam production, and design personnel to recommend changes that should improve material handling, operations, and maintenance procedures as well as simplifying piping and cabling. The company has already saved many man-hours in material take-off, material management, and detailed drafting and expects to save even more with greater use of, and improvement in, its modeling program. Duke's modeling program was authorized and became operational in November 1974, with the first model to be the Catawba Nuclear Station. This plant is a two-unit station using Westinghouse nuclear steam supply systems in tandem with General Electric turbine-generators, horizontal feedwater heaters, and Foster Wheeler triple pressure condensers. Each unit is rated 1142 MWe

  3. Towards a (Decentralization-Based Typology of Peer Production

    Directory of Open Access Journals (Sweden)

    Melanie Dulong de Rosnay

    2016-03-01

    Full Text Available Online peer-production platforms facilitate the coordination of creative work and services. Generally considered as empowering participatory tools and a source of common good, they can also be, however, alienating instruments of digital labour. This paper proposes a typology of peer-production platforms, based on the centralization/decentralization levels of several of their design features. Between commons-based peer-production and crowdsourced, user-generated content “enclosed” by corporations, a wide range of models combine different social, political, technical and economic arrangements. This combined analysis of the level of (decentralization of platform features provides information on emancipation capabilities in a more granular way than a market-based qualification of platforms, based on the nature of ownership or business models only. The five selected features of the proposed typology are: ownership of means of production, technical architecture/design, social organization/governance of work patterns, ownership of the peer-produced resource, and value of the output.

  4. Planck-scale corrections to axion models

    International Nuclear Information System (INIS)

    Barr, S.M.; Seckel, D.

    1992-01-01

    It has been argued that quantum gravitational effects will violate all nonlocal symmetries. Peccei-Quinn symmetries must therefore be an ''accidental'' or automatic consequence of local gauge symmetry. Moreover, higher-dimensional operators suppressed by powers of M Pl are expected to explicitly violate the Peccei-Quinn symmetry. Unless these operators are of dimension d≥10, axion models do not solve the strong CP problem in a natural fashion. A small gravitationally induced contribution to the axion mass has little if any effect on the density of relic axions. If d=10, 11, or 12 these operators can solve the axion domain-wall problem, and we describe a simple class of Kim-Shifman-Vainshtein-Zakharov axion models where this occurs. We also study the astrophysics and cosmology of ''heavy axions'' in models where 5≤d≤10

  5. Scaling limit for the Derezi\\'nski-G\\'erard model

    OpenAIRE

    OHKUBO, Atsushi

    2010-01-01

    We consider a scaling limit for the Derezi\\'nski-G\\'erard model. We derive an effective potential by taking a scaling limit for the total Hamiltonian of the Derezi\\'nski-G\\'erard model. Our method to derive an effective potential is independent of whether or not the quantum field has a nonnegative mass. As an application of our theory developed in the present paper, we derive an effective potential of the Nelson model.

  6. BLEVE overpressure: multi-scale comparison of blast wave modeling

    International Nuclear Information System (INIS)

    Laboureur, D.; Buchlin, J.M.; Rambaud, P.; Heymes, F.; Lapebie, E.

    2014-01-01

    BLEVE overpressure modeling has been already widely studied but only few validations including the scale effect have been made. After a short overview of the main models available in literature, a comparison is done with different scales of measurements, taken from previous studies or coming from experiments performed in the frame of this research project. A discussion on the best model to use in different cases is finally proposed. (authors)

  7. Dynamically Scaled Model Experiment of a Mooring Cable

    Directory of Open Access Journals (Sweden)

    Lars Bergdahl

    2016-01-01

    Full Text Available The dynamic response of mooring cables for marine structures is scale-dependent, and perfect dynamic similitude between full-scale prototypes and small-scale physical model tests is difficult to achieve. The best possible scaling is here sought by means of a specific set of dimensionless parameters, and the model accuracy is also evaluated by two alternative sets of dimensionless parameters. A special feature of the presented experiment is that a chain was scaled to have correct propagation celerity for longitudinal elastic waves, thus providing perfect geometrical and dynamic scaling in vacuum, which is unique. The scaling error due to incorrect Reynolds number seemed to be of minor importance. The 33 m experimental chain could then be considered a scaled 76 mm stud chain with the length 1240 m, i.e., at the length scale of 1:37.6. Due to the correct elastic scale, the physical model was able to reproduce the effect of snatch loads giving rise to tensional shock waves propagating along the cable. The results from the experiment were used to validate the newly developed cable-dynamics code, MooDy, which utilises a discontinuous Galerkin FEM formulation. The validation of MooDy proved to be successful for the presented experiments. The experimental data is made available here for validation of other numerical codes by publishing digitised time series of two of the experiments.

  8. Multi-area market clearing in wind-integrated interconnected power systems: A fast parallel decentralized method

    International Nuclear Information System (INIS)

    Doostizadeh, Meysam; Aminifar, Farrokh; Lesani, Hamid; Ghasemi, Hassan

    2016-01-01

    Highlights: • A parallel-decentralized multi-area energy & reserve clearance model is proposed. • A fictitious area and joint variables coordinate & parallelize area market models. • Adjustable intervals of random variables compromise optimality and robustness. • The stochastic nature of problem is tackled in an efficient deterministic manner. • The model is compact and applicable in multi-area real-scale systems. - Abstract: The growing evolution of regional electricity markets and proliferation of wind power penetration underline the prominence of coordinated operation of interconnected regional power systems. This paper develops a parallel decentralized methodology for multi-area energy and reserve clearance under wind power uncertainty. Preserving the independency of regional markets while fully taking the advantages of interconnection is a salient feature of the new model. Additionally, the parallel procedure simultaneously clears regional markets for the sake of acceleration particularly in large-scale systems. In order to achieve the optimal solution in a distributed fashion, the augmented Lagrangian relaxation along with alternative direction method of multipliers are applied. The wind power intermittency and uncertainty are tackled through the interval optimization approach. Opposed to the conventional wisdom, adjustable intervals, as subsets of conventional predefined intervals, are introduced here to compromise the cost and conservatism of the solution. The confidence level approach is employed to accommodate the stochastic nature of wind power in a computationally efficient deterministic manner. The effectiveness and robustness of the proposed method are evaluated through several case studies on a two-area 6-bus and the modified three-area IEEE 118-bus test systems.

  9. (DeCentralization of the Global Informational Ecosystem

    Directory of Open Access Journals (Sweden)

    Johanna Möller

    2017-09-01

    Full Text Available Centralization and decentralization are key concepts in debates that focus on the (antidemocratic character of digital societies. Centralization is understood as the control over communication and data flows, and decentralization as giving it (back to users. Communication and media research focuses on centralization put forward by dominant digital media platforms, such as Facebook and Google, and governments. Decentralization is investigated regarding its potential in civil society, i.e., hacktivism, (encryption technologies, and grass-root technology movements. As content-based media companies increasingly engage with technology, they move into the focus of critical media studies. Moreover, as formerly nationally oriented companies now compete with global media platforms, they share several interests with civil society decentralization agents. Based on 26 qualitative interviews with leading media managers, we investigate (decentralization strategies applied by content-oriented media companies. Theoretically, this perspective on media companies as agents of (decentralization expands (decentralization research beyond traditional democratic stakeholders by considering economic actors within the “global informational ecosystem” (Birkinbine, Gómez, & Wasko, 2017. We provide a three-dimensional framework to empirically investigate (decentralization. From critical media studies, we borrow the (decentralization of data and infrastructures, from media business research, the (decentralization of content distribution.

  10. Analysis of chromosome aberration data by hybrid-scale models

    International Nuclear Information System (INIS)

    Indrawati, Iwiq; Kumazawa, Shigeru

    2000-02-01

    This paper presents a new methodology for analyzing data of chromosome aberrations, which is useful to understand the characteristics of dose-response relationships and to construct the calibration curves for the biological dosimetry. The hybrid scale of linear and logarithmic scales brings a particular plotting paper, where the normal section paper, two types of semi-log papers and the log-log paper are continuously connected. The hybrid-hybrid plotting paper may contain nine kinds of linear relationships, and these are conveniently called hybrid scale models. One can systematically select the best-fit model among the nine models by among the conditions for a straight line of data points. A biological interpretation is possible with some hybrid-scale models. In this report, the hybrid scale models were applied to separately reported data on chromosome aberrations in human lymphocytes as well as on chromosome breaks in Tradescantia. The results proved that the proposed models fit the data better than the linear-quadratic model, despite the demerit of the increased number of model parameters. We showed that the hybrid-hybrid model (both variables of dose and response using the hybrid scale) provides the best-fit straight lines to be used as the reliable and readable calibration curves of chromosome aberrations. (author)

  11. Flavor gauge models below the Fermi scale

    Science.gov (United States)

    Babu, K. S.; Friedland, A.; Machado, P. A. N.; Mocioiu, I.

    2017-12-01

    The mass and weak interaction eigenstates for the quarks of the third generation are very well aligned, an empirical fact for which the Standard Model offers no explanation. We explore the possibility that this alignment is due to an additional gauge symmetry in the third generation. Specifically, we construct and analyze an explicit, renormalizable model with a gauge boson, X, corresponding to the B - L symmetry of the third family. Having a relatively light (in the MeV to multi-GeV range), flavor-nonuniversal gauge boson results in a variety of constraints from different sources. By systematically analyzing 20 different constraints, we identify the most sensitive probes: kaon, B +, D + and Upsilon decays, D-{\\overline{D}}^0 mixing, atomic parity violation, and neutrino scattering and oscillations. For the new gauge coupling g X in the range (10-2-10-4) the model is shown to be consistent with the data. Possible ways of testing the model in b physics, top and Z decays, direct collider production and neutrino oscillation experiments, where one can observe nonstandard matter effects, are outlined. The choice of leptons to carry the new force is ambiguous, resulting in additional phenomenological implications, such as non-universality in semileptonic bottom decays. The proposed framework provides interesting connections between neutrino oscillations, flavor and collider physics.

  12. Centralization vs. Decentralization in Medical School Libraries

    Science.gov (United States)

    Crawford, Helen

    1966-01-01

    Does the medical school library in the United States operate more commonly under the university library or the medical school administration? University-connected medical school libraries were asked to indicate (a) the source of their budgets, whether from the central library or the medical school, and (b) the responsibility for their acquisitions and cataloging. Returns received from sixtyeight of the seventy eligible institutions showed decentralization to be much the most common: 71 percent of the libraries are funded by their medical schools; 79 percent are responsible for their own acquisitions and processing. The factor most often associated with centralization of both budget and operation is public ownership. Decentralization is associated with service to one or two rather than three or more professional schools. Location of the medical school in a different city from the university is highly favorable to autonomy. Other factors associated with these trends are discussed. PMID:5945568

  13. Centralization vs. decentralization in medical school libraries.

    Science.gov (United States)

    Crawford, H

    1966-07-01

    Does the medical school library in the United States operate more commonly under the university library or the medical school administration? University-connected medical school libraries were asked to indicate (a) the source of their budgets, whether from the central library or the medical school, and (b) the responsibility for their acquisitions and cataloging. Returns received from sixtyeight of the seventy eligible institutions showed decentralization to be much the most common: 71 percent of the libraries are funded by their medical schools; 79 percent are responsible for their own acquisitions and processing. The factor most often associated with centralization of both budget and operation is public ownership. Decentralization is associated with service to one or two rather than three or more professional schools. Location of the medical school in a different city from the university is highly favorable to autonomy. Other factors associated with these trends are discussed.

  14. [Unfolding item response model using best-worst scaling].

    Science.gov (United States)

    Ikehara, Kazuya

    2015-02-01

    In attitude measurement and sensory tests, the unfolding model is typically used. In this model, response probability is formulated by the distance between the person and the stimulus. In this study, we proposed an unfolding item response model using best-worst scaling (BWU model), in which a person chooses the best and worst stimulus among repeatedly presented subsets of stimuli. We also formulated an unfolding model using best scaling (BU model), and compared the accuracy of estimates between the BU and BWU models. A simulation experiment showed that the BWU modell performed much better than the BU model in terms of bias and root mean square errors of estimates. With reference to Usami (2011), the proposed models were apllied to actual data to measure attitudes toward tardiness. Results indicated high similarity between stimuli estimates generated with the proposed models and those of Usami (2011).

  15. Sizing and scaling requirements of a large-scale physical model for code validation

    International Nuclear Information System (INIS)

    Khaleel, R.; Legore, T.

    1990-01-01

    Model validation is an important consideration in application of a code for performance assessment and therefore in assessing the long-term behavior of the engineered and natural barriers of a geologic repository. Scaling considerations relevant to porous media flow are reviewed. An analysis approach is presented for determining the sizing requirements of a large-scale, hydrology physical model. The physical model will be used to validate performance assessment codes that evaluate the long-term behavior of the repository isolation system. Numerical simulation results for sizing requirements are presented for a porous medium model in which the media properties are spatially uncorrelated

  16. Pelamis wave energy converter. Verification of full-scale control using a 7th scale model

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    The Pelamis Wave Energy Converter is a new concept for converting wave energy for several applications including generation of electric power. The machine is flexibly moored and swings to meet the water waves head-on. The system is semi-submerged and consists of cylindrical sections linked by hinges. The mechanical operation is described in outline. A one-seventh scale model was built and tested and the outcome was sufficiently successful to warrant the building of a full-scale prototype. In addition, a one-twentieth scale model was built and has contributed much to the research programme. The work is supported financially by the DTI.

  17. Do Decentralized Innovation Systems Promote Agricultural Technology Adoption? Experimental Evidence from Africa

    NARCIS (Netherlands)

    Pamuk, Haki; Bulte, Erwin|info:eu-repo/dai/nl/141315245; Adekunle, Adewale A.

    2014-01-01

    We use experimental data collected in 8 African countries to investigate whether a decentralized approach can promote the adoption of agricultural innovations. This participatory model is based on the creation of so-called ‘innovation platforms’ where local stakeholders meet and seek to identify

  18. Integration of capacity, pricing, and lead-time decisions in a decentralized supply chain

    NARCIS (Netherlands)

    Zhu, Stuart X.

    We consider a decentralized supply chain consisting of a supplier and a retailer facing price- and lead-time-sensitive demand. The decision process is modelled by a Stackelberg game where the supplier, as a leader, determines the capacity and the wholesale price, and the retailer, as a follower,

  19. Circulation Clusters--An Empirical Approach to Decentralization of Academic Libraries.

    Science.gov (United States)

    McGrath, William E.

    1986-01-01

    Discusses the issue of centralization or decentralization of academic library collections, and describes a statistical analysis of book circulation at the University of Southwestern Louisiana that yielded subject area clusters as a compromise solution to the problem. Applications of the cluster model for all types of library catalogs are…

  20. Decision Making Configurations: An Alternative to the Centralization/Decentralization Conceptualization.

    Science.gov (United States)

    Cullen, John B.; Perrewe, Pamela L.

    1981-01-01

    Used factors identified in the literature as predictors of centralization/decentralization as potential discriminating variables among several decision making configurations in university affiliated professional schools. The model developed from multiple discriminant analysis had reasonable success in classifying correctly only the decentralized…

  1. Centralization versus decentralization as a risk-return trade-off

    NARCIS (Netherlands)

    Arcuri, A.; Dari-Mattiacci, G.

    2010-01-01

    This paper characterizes the choice between centralization and decentralization as a risk‐return trade‐off and examines it in a model that integrates ideas from committee decision‐making and portfolio theories. Centralization, by pooling expertise, rarely yields erroneous decisions; however, when it

  2. On the Feasibility of Decentralized Derivatives Markets

    OpenAIRE

    Eskandari, Shayan; Clark, Jeremy; Sundaresan, Vignesh; Adham, Moe

    2018-01-01

    In this paper, we present Velocity, a decentralized market deployed on Ethereum for trading a custom type of derivative option. To enable the smart contract to work, we also implement a price fetching tool called PriceGeth. We present this as a case study, noting challenges in development of the system that might be of independent interest to whose working on smart contract implementations. We also apply recent academic results on the security of the Solidity smart contract language in valida...

  3. Quantifying risk for decentralized offensive cyber operations

    OpenAIRE

    Klipstein, Michael S.

    2017-01-01

    Approved for public release; distribution is unlimited Includes supplementary material. Reissued 7 Sep 2017 with corrections to committee titles. Computer networks and the amount of information stored within government computer networks have become ubiquitous. With the possible decentralization of authorities to conduct offensive cyber operations, leaders and their respective staffs of organizations below the national level cannot adequately assess risks and consequences of these ope...

  4. Grey water reclamation by decentralized MBR prototype

    OpenAIRE

    Santasmasas Rubiralta, Carme; Rovira Boixaderas, Miquel; Clarens Blanco, Frederic; Valderrama Angel, César Alberto

    2013-01-01

    Grey water treatment and reuse for non-drinking water requirements has become of great interest in arid and semi-arid zones where water resources are becoming both quantitatively and qualitatively scarce. In this study a decentralized and automatic MBR prototype has been designed and installed in the REMOSA facilities for treatment of low-load grey water to be recycled in flushing-toilet application. The recycling treatment of grey water comprises four stages: screening, biological oxidation,...

  5. Analyzing Von Neumann machines using decentralized symmetries

    Science.gov (United States)

    Fang, Jie

    2013-10-01

    The artificial intelligence method to e-business is defined not only by the study of fiber-optic cables, but also by the unproven need for vacuum tubes. Given the current status of virtual archetypes, theorists clearly desire the exploration of semaphores, which embodies the compelling principles of cryptoanalysis. We present an algorithm for probabilistic theory (Buck), which we use to disprove that write-back caches can be made decentralized, lossless, and reliable.

  6. The effects of fiscal decentralization in Albania

    OpenAIRE

    Dr.Sc. Blerta Dragusha; Dr.Sc. Elez Osmani

    2012-01-01

    “Basically decentralization is a democratic reform which seeks to transfer the political, administrative, financial and planning authority from central to local government. It seeks to develop civic participation, empowerment of local people in decision making process and to promote accountability and reliability: To achieve efficiency and effectiveness in the collection and management of resources and service delivery”1 The interest and curiosity of knowing how our country is doing in th...

  7. Witnet: A Decentralized Oracle Network Protocol

    OpenAIRE

    de Pedro, Adán Sánchez; Levi, Daniele; Cuende, Luis Iván

    2017-01-01

    Witnet is a decentralized oracle network (DON) that connects smart contracts to the outer world. Generally speaking, it allows any piece of software to retrieve the contents published at any web address at a certain point in time, with complete and verifiable proof of its integrity and without blindly trusting any third party. Witnet runs on a blockchain with a native protocol token (called Wit), which miners-called witnesses-earn by retrieving, attesting and delivering web contents for clien...

  8. Atomic-scale modeling of cellulose nanocrystals

    Science.gov (United States)

    Wu, Xiawa

    Cellulose nanocrystals (CNCs), the most abundant nanomaterials in nature, are recognized as one of the most promising candidates to meet the growing demand of green, bio-degradable and sustainable nanomaterials for future applications. CNCs draw significant interest due to their high axial elasticity and low density-elasticity ratio, both of which are extensively researched over the years. In spite of the great potential of CNCs as functional nanoparticles for nanocomposite materials, a fundamental understanding of CNC properties and their role in composite property enhancement is not available. In this work, CNCs are studied using molecular dynamics simulation method to predict their material' behaviors in the nanoscale. (a) Mechanical properties include tensile deformation in the elastic and plastic regions using molecular mechanics, molecular dynamics and nanoindentation methods. This allows comparisons between the methods and closer connectivity to experimental measurement techniques. The elastic moduli in the axial and transverse directions are obtained and the results are found to be in good agreement with previous research. The ultimate properties in plastic deformation are reported for the first time and failure mechanism are analyzed in details. (b) The thermal expansion of CNC crystals and films are studied. It is proposed that CNC film thermal expansion is due primarily to single crystal expansion and CNC-CNC interfacial motion. The relative contributions of inter- and intra-crystal responses to heating are explored. (c) Friction at cellulose-CNCs and diamond-CNCs interfaces is studied. The effects of sliding velocity, normal load, and relative angle between sliding surfaces are predicted. The Cellulose-CNC model is analyzed in terms of hydrogen bonding effect, and the diamond-CNC model compliments some of the discussion of the previous model. In summary, CNC's material properties and molecular models are both studied in this research, contributing to

  9. Sensitivities in global scale modeling of isoprene

    Directory of Open Access Journals (Sweden)

    R. von Kuhlmann

    2004-01-01

    Full Text Available A sensitivity study of the treatment of isoprene and related parameters in 3D atmospheric models was conducted using the global model of tropospheric chemistry MATCH-MPIC. A total of twelve sensitivity scenarios which can be grouped into four thematic categories were performed. These four categories consist of simulations with different chemical mechanisms, different assumptions concerning the deposition characteristics of intermediate products, assumptions concerning the nitrates from the oxidation of isoprene and variations of the source strengths. The largest differences in ozone compared to the reference simulation occured when a different isoprene oxidation scheme was used (up to 30-60% or about 10 nmol/mol. The largest differences in the abundance of peroxyacetylnitrate (PAN were found when the isoprene emission strength was reduced by 50% and in tests with increased or decreased efficiency of the deposition of intermediates. The deposition assumptions were also found to have a significant effect on the upper tropospheric HOx production. Different implicit assumptions about the loss of intermediate products were identified as a major reason for the deviations among the tested isoprene oxidation schemes. The total tropospheric burden of O3 calculated in the sensitivity runs is increased compared to the background methane chemistry by 26±9  Tg( O3 from 273 to an average from the sensitivity runs of 299 Tg(O3. % revised Thus, there is a spread of ± 35% of the overall effect of isoprene in the model among the tested scenarios. This range of uncertainty and the much larger local deviations found in the test runs suggest that the treatment of isoprene in global models can only be seen as a first order estimate at present, and points towards specific processes in need of focused future work.

  10. Scaling of musculoskeletal models from static and dynamic trials

    DEFF Research Database (Denmark)

    Lund, Morten Enemark; Andersen, Michael Skipper; de Zee, Mark

    2015-01-01

    Subject-specific scaling of cadaver-based musculoskeletal models is important for accurate musculoskeletal analysis within multiple areas such as ergonomics, orthopaedics and occupational health. We present two procedures to scale ‘generic’ musculoskeletal models to match segment lengths and joint...... three scaling methods to an inverse dynamics-based musculoskeletal model and compared predicted knee joint contact forces to those measured with an instrumented prosthesis during gait. Additionally, a Monte Carlo study was used to investigate the sensitivity of the knee joint contact force to random...

  11. MOUNTAIN-SCALE COUPLED PROCESSES (TH/THC/THM)MODELS

    Energy Technology Data Exchange (ETDEWEB)

    Y.S. Wu

    2005-08-24

    This report documents the development and validation of the mountain-scale thermal-hydrologic (TH), thermal-hydrologic-chemical (THC), and thermal-hydrologic-mechanical (THM) models. These models provide technical support for screening of features, events, and processes (FEPs) related to the effects of coupled TH/THC/THM processes on mountain-scale unsaturated zone (UZ) and saturated zone (SZ) flow at Yucca Mountain, Nevada (BSC 2005 [DIRS 174842], Section 2.1.1.1). The purpose and validation criteria for these models are specified in ''Technical Work Plan for: Near-Field Environment and Transport: Coupled Processes (Mountain-Scale TH/THC/THM, Drift-Scale THC Seepage, and Drift-Scale Abstraction) Model Report Integration'' (BSC 2005 [DIRS 174842]). Model results are used to support exclusion of certain FEPs from the total system performance assessment for the license application (TSPA-LA) model on the basis of low consequence, consistent with the requirements of 10 CFR 63.342 [DIRS 173273]. Outputs from this report are not direct feeds to the TSPA-LA. All the FEPs related to the effects of coupled TH/THC/THM processes on mountain-scale UZ and SZ flow are discussed in Sections 6 and 7 of this report. The mountain-scale coupled TH/THC/THM processes models numerically simulate the impact of nuclear waste heat release on the natural hydrogeological system, including a representation of heat-driven processes occurring in the far field. The mountain-scale TH simulations provide predictions for thermally affected liquid saturation, gas- and liquid-phase fluxes, and water and rock temperature (together called the flow fields). The main focus of the TH model is to predict the changes in water flux driven by evaporation/condensation processes, and drainage between drifts. The TH model captures mountain-scale three-dimensional flow effects, including lateral diversion and mountain-scale flow patterns. The mountain-scale THC model evaluates TH effects on

  12. MOUNTAIN-SCALE COUPLED PROCESSES (TH/THC/THM) MODELS

    International Nuclear Information System (INIS)

    Y.S. Wu

    2005-01-01

    This report documents the development and validation of the mountain-scale thermal-hydrologic (TH), thermal-hydrologic-chemical (THC), and thermal-hydrologic-mechanical (THM) models. These models provide technical support for screening of features, events, and processes (FEPs) related to the effects of coupled TH/THC/THM processes on mountain-scale unsaturated zone (UZ) and saturated zone (SZ) flow at Yucca Mountain, Nevada (BSC 2005 [DIRS 174842], Section 2.1.1.1). The purpose and validation criteria for these models are specified in ''Technical Work Plan for: Near-Field Environment and Transport: Coupled Processes (Mountain-Scale TH/THC/THM, Drift-Scale THC Seepage, and Drift-Scale Abstraction) Model Report Integration'' (BSC 2005 [DIRS 174842]). Model results are used to support exclusion of certain FEPs from the total system performance assessment for the license application (TSPA-LA) model on the basis of low consequence, consistent with the requirements of 10 CFR 63.342 [DIRS 173273]. Outputs from this report are not direct feeds to the TSPA-LA. All the FEPs related to the effects of coupled TH/THC/THM processes on mountain-scale UZ and SZ flow are discussed in Sections 6 and 7 of this report. The mountain-scale coupled TH/THC/THM processes models numerically simulate the impact of nuclear waste heat release on the natural hydrogeological system, including a representation of heat-driven processes occurring in the far field. The mountain-scale TH simulations provide predictions for thermally affected liquid saturation, gas- and liquid-phase fluxes, and water and rock temperature (together called the flow fields). The main focus of the TH model is to predict the changes in water flux driven by evaporation/condensation processes, and drainage between drifts. The TH model captures mountain-scale three-dimensional flow effects, including lateral diversion and mountain-scale flow patterns. The mountain-scale THC model evaluates TH effects on water and gas

  13. Anomalous scaling in an age-dependent branching model

    OpenAIRE

    Keller-Schmidt, Stephanie; Tugrul, Murat; Eguiluz, Victor M.; Hernandez-Garcia, Emilio; Klemm, Konstantin

    2010-01-01

    We introduce a one-parametric family of tree growth models, in which branching probabilities decrease with branch age $\\tau$ as $\\tau^{-\\alpha}$. Depending on the exponent $\\alpha$, the scaling of tree depth with tree size $n$ displays a transition between the logarithmic scaling of random trees and an algebraic growth. At the transition ($\\alpha=1$) tree depth grows as $(\\log n)^2$. This anomalous scaling is in good agreement with the trend observed in evolution of biological species, thus p...

  14. Query Optimizations over Decentralized RDF Graphs

    KAUST Repository

    Abdelaziz, Ibrahim

    2017-05-18

    Applications in life sciences, decentralized social networks, Internet of Things, and statistical linked dataspaces integrate data from multiple decentralized RDF graphs via SPARQL queries. Several approaches have been proposed to optimize query processing over a small number of heterogeneous data sources by utilizing schema information. In the case of schema similarity and interlinks among sources, these approaches cause unnecessary data retrieval and communication, leading to poor scalability and response time. This paper addresses these limitations and presents Lusail, a system for scalable and efficient SPARQL query processing over decentralized graphs. Lusail achieves scalability and low query response time through various optimizations at compile and run times. At compile time, we use a novel locality-aware query decomposition technique that maximizes the number of query triple patterns sent together to a source based on the actual location of the instances satisfying these triple patterns. At run time, we use selectivity-awareness and parallel query execution to reduce network latency and to increase parallelism by delaying the execution of subqueries expected to return large results. We evaluate Lusail using real and synthetic benchmarks, with data sizes up to billions of triples on an in-house cluster and a public cloud. We show that Lusail outperforms state-of-the-art systems by orders of magnitude in terms of scalability and response time.

  15. Logarithmic corrections to scaling in the XY2-model

    International Nuclear Information System (INIS)

    Kenna, R.; Irving, A.C.

    1995-01-01

    We study the distribution of partition function zeroes for the XY-model in two dimensions. In particular we find the scaling behaviour of the end of the distribution of zeroes in the complex external magnetic field plane in the thermodynamic limit (the Yang-Lee edge) and the form for the density of these zeroes. Assuming that finite-size scaling holds, we show that there have to exist logarithmic corrections to the leading scaling behaviour of thermodynamic quantities in this model. These logarithmic corrections are also manifest in the finite-size scaling formulae and we identify them numerically. The method presented here can be used to check the compatibility of scaling behaviour of odd and even thermodynamic functions in other models too. ((orig.))

  16. a Model Study of Small-Scale World Map Generalization

    Science.gov (United States)

    Cheng, Y.; Yin, Y.; Li, C. M.; Wu, W.; Guo, P. P.; Ma, X. L.; Hu, F. M.

    2018-04-01

    With the globalization and rapid development every filed is taking an increasing interest in physical geography and human economics. There is a surging demand for small scale world map in large formats all over the world. Further study of automated mapping technology, especially the realization of small scale production on a large scale global map, is the key of the cartographic field need to solve. In light of this, this paper adopts the improved model (with the map and data separated) in the field of the mapmaking generalization, which can separate geographic data from mapping data from maps, mainly including cross-platform symbols and automatic map-making knowledge engine. With respect to the cross-platform symbol library, the symbol and the physical symbol in the geographic information are configured at all scale levels. With respect to automatic map-making knowledge engine consists 97 types, 1086 subtypes, 21845 basic algorithm and over 2500 relevant functional modules.In order to evaluate the accuracy and visual effect of our model towards topographic maps and thematic maps, we take the world map generalization in small scale as an example. After mapping generalization process, combining and simplifying the scattered islands make the map more explicit at 1 : 2.1 billion scale, and the map features more complete and accurate. Not only it enhance the map generalization of various scales significantly, but achieve the integration among map-makings of various scales, suggesting that this model provide a reference in cartographic generalization for various scales.

  17. Progress and challenges in utilization of palm oil biomass as fuel for decentralized electricity generation

    Energy Technology Data Exchange (ETDEWEB)

    Bazmi, Aqeel Ahmed [Process Systems Engineering Centre (PROSPECT), Department of Chemical Engineering, Faculty of Chemical and Natural Resources Engineering, University Technology Malaysia, Skudai 81310, Johor Bahru, JB (Malaysia); Biomass Conversion Research Center (BCRC), Department of Chemical Engineering, COMSATS Institute of Information Technology, Lahore (Pakistan); Zahedi, Gholamreza; Hashim, Haslenda [Process Systems Engineering Centre (PROSPECT), Department of Chemical Engineering, Faculty of Chemical and Natural Resources Engineering, University Technology Malaysia, Skudai 81310, Johor Bahru, JB (Malaysia)

    2011-01-15

    It has been broadly accepted worldwide that global warming, indeed, is the greatest threat of the time to the environment. Renewable energy (RE) is expected as a perfect solution to reduce global warming and to endorse sustainable development. Progressive release of greenhouse gases (GHG) from increasing energy-intensive industries has eventually caused human civilization to suffer. Realizing the exigency of reducing emissions and simultaneously catering to needs of industries, researchers foresee the RE as the perfect entrant to overcome these challenges. RE provides an effective option for the provision of energy services from the technical point of view while biomass, a major source of energy in the world until before industrialization when fossil fuels become dominant, appears an important renewable source of energy and researches have proven from time to time its viability for large-scale production. Being a widely spread source, biomass offers the execution of decentralized electricity generation gaining importance in liberalized electricity markets. The decentralized power is characterized by generation of electricity nearer to the demand centers, meeting the local energy needs. Researchers envisaged an increasing decentralization of power supply, expected to make a particular contribution to climate protection. This article investigates the progress and challenges for decentralized electricity generation by palm oil biomass according to the overall concept of sustainable development. (author)

  18. Progress and challenges in utilization of palm oil biomass as fuel for decentralized electricity generation

    International Nuclear Information System (INIS)

    Bazmi, Aqeel Ahmed; Zahedi, Gholamreza; Hashim, Haslenda

    2011-01-01

    It has been broadly accepted worldwide that global warming, indeed, is the greatest threat of the time to the environment. Renewable energy (RE) is expected as a perfect solution to reduce global warming and to endorse sustainable development. Progressive release of greenhouse gases (GHG) from increasing energy-intensive industries has eventually caused human civilization to suffer. Realizing the exigency of reducing emissions and simultaneously catering to needs of industries, researchers foresee the RE as the perfect entrant to overcome these challenges. RE provides an effective option for the provision of energy services from the technical point of view while biomass, a major source of energy in the world until before industrialization when fossil fuels become dominant, appears an important renewable source of energy and researches have proven from time to time its viability for large-scale production. Being a widely spread source, biomass offers the execution of decentralized electricity generation gaining importance in liberalized electricity markets. The decentralized power is characterized by generation of electricity nearer to the demand centers, meeting the local energy needs. Researchers envisaged an increasing decentralization of power supply, expected to make a particular contribution to climate protection. This article investigates the progress and challenges for decentralized electricity generation by palm oil biomass according to the overall concept of sustainable development. (author)

  19. Reference Priors for the General Location-Scale Model

    NARCIS (Netherlands)

    Fernández, C.; Steel, M.F.J.

    1997-01-01

    The reference prior algorithm (Berger and Bernardo 1992) is applied to multivariate location-scale models with any regular sampling density, where we establish the irrelevance of the usual assumption of Normal sampling if our interest is in either the location or the scale. This result immediately

  20. Penalized Estimation in Large-Scale Generalized Linear Array Models

    DEFF Research Database (Denmark)

    Lund, Adam; Vincent, Martin; Hansen, Niels Richard

    2017-01-01

    Large-scale generalized linear array models (GLAMs) can be challenging to fit. Computation and storage of its tensor product design matrix can be impossible due to time and memory constraints, and previously considered design matrix free algorithms do not scale well with the dimension...

  1. Federalism and decentralization: impact on international and Brazilian health policies.

    Science.gov (United States)

    Leite, Valéria Rodrigues; de Vasconcelos, Cipriano Maia; Lima, Kenio Costa

    2011-01-01

    This article discusses the implications of decentralization in the light of international and Brazilian federalism, and its effects on public health policy. In a comparative analysis among countries, the authors find there is no single model; rather, each country has a unique structure of institutions and norms that have important implications for the operation of its health system. Brazil shares some similarities with other countries that have adopted a decentralized system and is assuming features ever closer to U.S. federalism, with a complex web of relationships. The degree of inequality among Brazilian municipalities and states, along with the budgetary imbalances caused by the minimal levels of resource utilization, undermines Brazil's constitutional principles and, consequently, its federalism. To ensure the constitutional mandate in Brazil, it is essential, as in other countries, to create a stable source of funds and increase the volume and efficiency of spending. Also important are investing in the training of managers, improving information systems, strengthening the principles of autonomy and interdependence, and defining patterns of cooperation within the federation.

  2. Decentralized Hypothesis Testing in Energy Harvesting Wireless Sensor Networks

    Science.gov (United States)

    Tarighati, Alla; Gross, James; Jalden, Joakim

    2017-09-01

    We consider the problem of decentralized hypothesis testing in a network of energy harvesting sensors, where sensors make noisy observations of a phenomenon and send quantized information about the phenomenon towards a fusion center. The fusion center makes a decision about the present hypothesis using the aggregate received data during a time interval. We explicitly consider a scenario under which the messages are sent through parallel access channels towards the fusion center. To avoid limited lifetime issues, we assume each sensor is capable of harvesting all the energy it needs for the communication from the environment. Each sensor has an energy buffer (battery) to save its harvested energy for use in other time intervals. Our key contribution is to formulate the problem of decentralized detection in a sensor network with energy harvesting devices. Our analysis is based on a queuing-theoretic model for the battery and we propose a sensor decision design method by considering long term energy management at the sensors. We show how the performance of the system changes for different battery capacities. We then numerically show how our findings can be used in the design of sensor networks with energy harvesting sensors.

  3. The material politics of waste disposal - decentralization and integrated systems

    Directory of Open Access Journals (Sweden)

    Penelope Harvey

    2012-12-01

    Full Text Available This article and the previous «Convergence and divergence between the local and regional state around solid waste management. An unresolved problem in the Sacred Valley» from Teresa Tupayachi are published as complementary accounts on the management of solid waste in the Vilcanota Valley in Cusco. Penelope Harvey and Teresa Tupayachi worked together on this theme. The present article explores how discontinuities across diverse instances of the state are experienced and understood. Drawing from an ethnographic study of the Vilcanota Valley in Cusco, the article looks at the material politics of waste disposal in neoliberal times. Faced with the problem of how to dispose of solid waste, people from Cusco experience a lack of institutional responsibility and call for a stronger state presence. The article describes the efforts by technical experts to design integrated waste management systems that maximise the potential for re-cycling, minimise toxic contamination, and turn ‘rubbish’ into the altogether more economically lively category of ‘solid waste’. However while the financialization of waste might appear to offer an indisputable public good, efforts to instigate a viable waste disposal business in a decentralizing political space elicit deep social tensions and contradictions. The social discontinuities that decentralization supports disrupt ambitions for integrated solutions as local actors resist top-down models and look not just for alternative solutions, but alternative ways of framing the problem of urban waste, and by extension their relationship to the state.

  4. Optimal centralized and decentralized velocity feedback control on a beam

    International Nuclear Information System (INIS)

    Engels, W P; Elliott, S J

    2008-01-01

    This paper considers the optimization of a velocity feedback controller with a collocated force actuator, to minimize the kinetic energy of a simply supported beam. If the beam is excited at a single location, the optimum feedback gain varies with the position of the control system. It is shown that this variation depends partly on the location of the control force relative to the exciting force. If a distributed excitation is assumed, that is random in both time and space, a unique optimum value of the feedback gain can be found for a given control location. The effect of the control location on performance and the optimal feedback gain can then be examined and is found to be limited provided the control locations are not close to the ends of the beam. The optimization can also be performed for a multichannel velocity feedback system. Both a centralized and a decentralized controller are considered. It is shown that the difference in performance between a centralized and a decentralized controller is small, unless the control locations are closely spaced. In this case the centralized controller effectively feeds back a moment proportional to angular velocity as well as a force proportional to a velocity. It is also shown that the optimal feedback gain can be approximated on the basis of a limited model and that similar results can be achieved

  5. A Decentralized Heuristic Approach towards Resource Allocation in Femtocell Networks

    Directory of Open Access Journals (Sweden)

    Kyung-Geun Lee

    2013-06-01

    Full Text Available Femtocells represent a novel configuration for existing cellular communication, contributing towards the improvement of coverage and throughput. The dense deployment of these femtocells causes significant femto-macro and femto-femto interference, consequently deteriorating the throughput of femtocells. In this study, we compare two heuristic approaches, i.e., particle swarm optimization (PSO and genetic algorithm (GA, for joint power assignment and resource allocation, within the context of the femtocell environment. The supposition made in this joint optimization is that the discrete power levels are available for the assignment. Furthermore, we have employed two variants of each PSO and GA: inertia weight and constriction factor model for PSO, and twopoint and uniform crossover for GA. The two proposed algorithms are in a decentralized manner, with no involvement of any centralized entity. The comparison is carried out between the two proposed algorithms for the aforementioned joint optimization problem. The contrast includes the performance metrics: including average objective function, min–max throughput of the femtocells, average throughput of the femto users, outage rate and time complexity. The results demonstrate that the decentralized PSO constriction factor outperforms the others in terms of the aforementioned performance metrics.

  6. Methane synthesis under mild conditions for decentralized applications

    International Nuclear Information System (INIS)

    Schlueter, Michael; Roensch, Stefan

    2016-01-01

    It is a central aim of the German government to significantly reduce the emission of greenhouse gases in the next years. One possibility to reach this aim is the substitution of fossil fuels, especially natural gas, by fuels from biogenic sources (Bio-SNG). However, it is a drawback of Bio-SNG that the production costs are considerably higher than those of fossil natural gas. This work provides an approach to reduce the production costs of Bio-SNG. It is the aim to reduce the process parameters of the methane synthesis. At the same time, it has to be ensured that high methane yields are achieved even at those mild conditions. A procedure for the optimization of the methanation catalyst activity will be presented. If the catalyst is as active as possible even at mild conditions, it will be possible to produce Bio-SNG cost efficient even in small, decentralized scale.

  7. Atomic scale simulations for improved CRUD and fuel performance modeling

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, Anders David Ragnar [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Cooper, Michael William Donald [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-01-06

    A more mechanistic description of fuel performance codes can be achieved by deriving models and parameters from atomistic scale simulations rather than fitting models empirically to experimental data. The same argument applies to modeling deposition of corrosion products on fuel rods (CRUD). Here are some results from publications in 2016 carried out using the CASL allocation at LANL.

  8. Genome-scale modeling for metabolic engineering.

    Science.gov (United States)

    Simeonidis, Evangelos; Price, Nathan D

    2015-03-01

    We focus on the application of constraint-based methodologies and, more specifically, flux balance analysis in the field of metabolic engineering, and enumerate recent developments and successes of the field. We also review computational frameworks that have been developed with the express purpose of automatically selecting optimal gene deletions for achieving improved production of a chemical of interest. The application of flux balance analysis methods in rational metabolic engineering requires a metabolic network reconstruction and a corresponding in silico metabolic model for the microorganism in question. For this reason, we additionally present a brief overview of automated reconstruction techniques. Finally, we emphasize the importance of integrating metabolic networks with regulatory information-an area which we expect will become increasingly important for metabolic engineering-and present recent developments in the field of metabolic and regulatory integration.

  9. Genome-scale biological models for industrial microbial systems.

    Science.gov (United States)

    Xu, Nan; Ye, Chao; Liu, Liming

    2018-04-01

    The primary aims and challenges associated with microbial fermentation include achieving faster cell growth, higher productivity, and more robust production processes. Genome-scale biological models, predicting the formation of an interaction among genetic materials, enzymes, and metabolites, constitute a systematic and comprehensive platform to analyze and optimize the microbial growth and production of biological products. Genome-scale biological models can help optimize microbial growth-associated traits by simulating biomass formation, predicting growth rates, and identifying the requirements for cell growth. With regard to microbial product biosynthesis, genome-scale biological models can be used to design product biosynthetic pathways, accelerate production efficiency, and reduce metabolic side effects, leading to improved production performance. The present review discusses the development of microbial genome-scale biological models since their emergence and emphasizes their pertinent application in improving industrial microbial fermentation of biological products.

  10. Particles and scaling for lattice fields and Ising models

    International Nuclear Information System (INIS)

    Glimm, J.; Jaffe, A.

    1976-01-01

    The conjectured inequality GAMMA 6 4 -fields and the scaling limit for d-dimensional Ising models. Assuming GAMMA 6 = 6 these phi 4 fields are free fields unless the field strength renormalization Z -1 diverges. (orig./BJ) [de

  11. Multi-scale modeling strategies in materials science—The ...

    Indian Academy of Sciences (India)

    Unknown

    Multi-scale models; quasicontinuum method; finite elements. 1. Introduction ... boundary with external stresses, and the interaction of a lattice dislocation with a grain ..... mum value of se over the elements that touch node α. The acceleration of ...

  12. Nonpointlike-parton model with asymptotic scaling and with scaling violationat moderate Q2 values

    International Nuclear Information System (INIS)

    Chen, C.K.

    1981-01-01

    A nonpointlike-parton model is formulated on the basis of the assumption of energy-independent total cross sections of partons and the current-algebra sum rules. No specific strong-interaction Lagrangian density is introduced in this approach. This model predicts asymptotic scaling for the inelastic structure functions of nucleons on the one hand and scaling violation at moderate Q 2 values on the other hand. The predicted scaling-violation patterns at moderate Q 2 values are consistent with the observed scaling-violation patterns. A numerical fit of F 2 functions is performed in order to demonstrate that the predicted scaling-violation patterns of this model at moderate Q 2 values fit the data, and to see how the predicted asymptotic scaling behavior sets in at various x values. Explicit analytic forms of F 2 functions are obtained from this numerical fit, and are compared in detail with the analytic forms of F 2 functions obtained from the numerical fit of the quantum-chromodynamics (QCD) parton model. This comparison shows that this nonpointlike-parton model fits the data better than the QCD parton model, especially at large and small x values. Nachtman moments are computed from the F 2 functions of this model and are shown to agree with data well. It is also shown that the two-dimensional plot of the logarithm of a nonsinglet moment versus the logarithm of another such moment is not a good way to distinguish this nonpointlike-parton model from the QCD parton model

  13. Multi-scale modeling for sustainable chemical production

    DEFF Research Database (Denmark)

    Zhuang, Kai; Bakshi, Bhavik R.; Herrgard, Markus

    2013-01-01

    associated with the development and implementation of a su stainable biochemical industry. The temporal and spatial scales of modeling approaches for sustainable chemical production vary greatly, ranging from metabolic models that aid the design of fermentative microbial strains to material and monetary flow......With recent advances in metabolic engineering, it is now technically possible to produce a wide portfolio of existing petrochemical products from biomass feedstock. In recent years, a number of modeling approaches have been developed to support the engineering and decision-making processes...... models that explore the ecological impacts of all economic activities. Research efforts that attempt to connect the models at different scales have been limited. Here, we review a number of existing modeling approaches and their applications at the scales of metabolism, bioreactor, overall process...

  14. Calibration of the Site-Scale Saturated Zone Flow Model

    International Nuclear Information System (INIS)

    Zyvoloski, G. A.

    2001-01-01

    The purpose of the flow calibration analysis work is to provide Performance Assessment (PA) with the calibrated site-scale saturated zone (SZ) flow model that will be used to make radionuclide transport calculations. As such, it is one of the most important models developed in the Yucca Mountain project. This model will be a culmination of much of our knowledge of the SZ flow system. The objective of this study is to provide a defensible site-scale SZ flow and transport model that can be used for assessing total system performance. A defensible model would include geologic and hydrologic data that are used to form the hydrogeologic framework model; also, it would include hydrochemical information to infer transport pathways, in-situ permeability measurements, and water level and head measurements. In addition, the model should include information on major model sensitivities. Especially important are those that affect calibration, the direction of transport pathways, and travel times. Finally, if warranted, alternative calibrations representing different conceptual models should be included. To obtain a defensible model, all available data should be used (or at least considered) to obtain a calibrated model. The site-scale SZ model was calibrated using measured and model-generated water levels and hydraulic head data, specific discharge calculations, and flux comparisons along several of the boundaries. Model validity was established by comparing model-generated permeabilities with the permeability data from field and laboratory tests; by comparing fluid pathlines obtained from the SZ flow model with those inferred from hydrochemical data; and by comparing the upward gradient generated with the model with that observed in the field. This analysis is governed by the Office of Civilian Radioactive Waste Management (OCRWM) Analysis and Modeling Report (AMR) Development Plan ''Calibration of the Site-Scale Saturated Zone Flow Model'' (CRWMS M and O 1999a)

  15. 3-3-1 models at electroweak scale

    International Nuclear Information System (INIS)

    Dias, Alex G.; Montero, J.C.; Pleitez, V.

    2006-01-01

    We show that in 3-3-1 models there exist a natural relation among the SU(3) L coupling constant g, the electroweak mixing angle θ W , the mass of the W, and one of the vacuum expectation values, which implies that those models can be realized at low energy scales and, in particular, even at the electroweak scale. So that, being that symmetries realized in Nature, new physics may be really just around the corner

  16. Mechanistically-Based Field-Scale Models of Uranium Biogeochemistry from Upscaling Pore-Scale Experiments and Models

    International Nuclear Information System (INIS)

    Tim Scheibe; Alexandre Tartakovsky; Brian Wood; Joe Seymour

    2007-01-01

    Effective environmental management of DOE sites requires reliable prediction of reactive transport phenomena. A central issue in prediction of subsurface reactive transport is the impact of multiscale physical, chemical, and biological heterogeneity. Heterogeneity manifests itself through incomplete mixing of reactants at scales below those at which concentrations are explicitly defined (i.e., the numerical grid scale). This results in a mismatch between simulated reaction processes (formulated in terms of average concentrations) and actual processes (controlled by local concentrations). At the field scale, this results in apparent scale-dependence of model parameters and inability to utilize laboratory parameters in field models. Accordingly, most field modeling efforts are restricted to empirical estimation of model parameters by fitting to field observations, which renders extrapolation of model predictions beyond fitted conditions unreliable. The objective of this project is to develop a theoretical and computational framework for (1) connecting models of coupled reactive transport from pore-scale processes to field-scale bioremediation through a hierarchy of models that maintain crucial information from the smaller scales at the larger scales; and (2) quantifying the uncertainty that is introduced by both the upscaling process and uncertainty in physical parameters. One of the challenges of addressing scale-dependent effects of coupled processes in heterogeneous porous media is the problem-specificity of solutions. Much effort has been aimed at developing generalized scaling laws or theories, but these require restrictive assumptions that render them ineffective in many real problems. We propose instead an approach that applies physical and numerical experiments at small scales (specifically the pore scale) to a selected model system in order to identify the scaling approach appropriate to that type of problem. Although the results of such studies will

  17. Mechanistically-Based Field-Scale Models of Uranium Biogeochemistry from Upscaling Pore-Scale Experiments and Models

    Energy Technology Data Exchange (ETDEWEB)

    Tim Scheibe; Alexandre Tartakovsky; Brian Wood; Joe Seymour

    2007-04-19

    Effective environmental management of DOE sites requires reliable prediction of reactive transport phenomena. A central issue in prediction of subsurface reactive transport is the impact of multiscale physical, chemical, and biological heterogeneity. Heterogeneity manifests itself through incomplete mixing of reactants at scales below those at which concentrations are explicitly defined (i.e., the numerical grid scale). This results in a mismatch between simulated reaction processes (formulated in terms of average concentrations) and actual processes (controlled by local concentrations). At the field scale, this results in apparent scale-dependence of model parameters and inability to utilize laboratory parameters in field models. Accordingly, most field modeling efforts are restricted to empirical estimation of model parameters by fitting to field observations, which renders extrapolation of model predictions beyond fitted conditions unreliable. The objective of this project is to develop a theoretical and computational framework for (1) connecting models of coupled reactive transport from pore-scale processes to field-scale bioremediation through a hierarchy of models that maintain crucial information from the smaller scales at the larger scales; and (2) quantifying the uncertainty that is introduced by both the upscaling process and uncertainty in physical parameters. One of the challenges of addressing scale-dependent effects of coupled processes in heterogeneous porous media is the problem-specificity of solutions. Much effort has been aimed at developing generalized scaling laws or theories, but these require restrictive assumptions that render them ineffective in many real problems. We propose instead an approach that applies physical and numerical experiments at small scales (specifically the pore scale) to a selected model system in order to identify the scaling approach appropriate to that type of problem. Although the results of such studies will

  18. EFFECT OF FISCAL DECENTRALIZATION ON CAPITAL EXPENDITURE, GROWTH, AND WELFARE

    OpenAIRE

    Badrudin, Rudy

    2013-01-01

    This research analyzes the influence of fiscal decentralization on capital expenditure, economic growth, and social welfare of 29 regencies and 6 cities in Central Java Province based on the data of year 2004 to 2008. The method used to analyze the hypotheses is the Partial Least Square. The results showes that fiscal decentralization has no significant effect on capital expenditure; fiscal decentralization has significant effect on economic growth and social welfare; capital expenditure has ...

  19. Comparison of centralized and decentralized energy supply systems

    OpenAIRE

    Pfeifer, Thomas; Fahl, Ulrich; Voß, Alfred

    1991-01-01

    Communal energy programs are often embedded in a conception of a decentralized energy supply system where electricity is produced by a number of smaller power plants. For a comprehensive survey the question arises whether these decentralized systems are more advantageous than centralized systems with regard to the criterions energy consumption, safety of supply, environmental compatibility and economy. In the following, after a definition of the term "decentralized", the present structure of ...

  20. (De)centralization of the global informational ecosystem

    OpenAIRE

    Möller, Johanna; Rimscha, M. Bjørn von

    2017-01-01

    Centralization and decentralization are key concepts in debates that focus on the (anti)democratic character of digital societies. Centralization is understood as the control over communication and data flows, and decentralization as giving it (back) to users. Communication and media research focuses on centralization put forward by dominant digital media platforms, such as Facebook and Google, and governments. Decentralization is investigated regarding its potential in civil society, i.e., h...

  1. [Modeling continuous scaling of NDVI based on fractal theory].

    Science.gov (United States)

    Luan, Hai-Jun; Tian, Qing-Jiu; Yu, Tao; Hu, Xin-Li; Huang, Yan; Du, Ling-Tong; Zhao, Li-Min; Wei, Xi; Han, Jie; Zhang, Zhou-Wei; Li, Shao-Peng

    2013-07-01

    Scale effect was one of the very important scientific problems of remote sensing. The scale effect of quantitative remote sensing can be used to study retrievals' relationship between different-resolution images, and its research became an effective way to confront the challenges, such as validation of quantitative remote sensing products et al. Traditional up-scaling methods cannot describe scale changing features of retrievals on entire series of scales; meanwhile, they are faced with serious parameters correction issues because of imaging parameters' variation of different sensors, such as geometrical correction, spectral correction, etc. Utilizing single sensor image, fractal methodology was utilized to solve these problems. Taking NDVI (computed by land surface radiance) as example and based on Enhanced Thematic Mapper Plus (ETM+) image, a scheme was proposed to model continuous scaling of retrievals. Then the experimental results indicated that: (a) For NDVI, scale effect existed, and it could be described by fractal model of continuous scaling; (2) The fractal method was suitable for validation of NDVI. All of these proved that fractal was an effective methodology of studying scaling of quantitative remote sensing.

  2. SCALING ANALYSIS OF REPOSITORY HEAT LOAD FOR REDUCED DIMENSIONALITY MODELS

    International Nuclear Information System (INIS)

    MICHAEL T. ITAMUA AND CLIFFORD K. HO

    1998-01-01

    The thermal energy released from the waste packages emplaced in the potential Yucca Mountain repository is expected to result in changes in the repository temperature, relative humidity, air mass fraction, gas flow rates, and other parameters that are important input into the models used to calculate the performance of the engineered system components. In particular, the waste package degradation models require input from thermal-hydrologic models that have higher resolution than those currently used to simulate the T/H responses at the mountain-scale. Therefore, a combination of mountain- and drift-scale T/H models is being used to generate the drift thermal-hydrologic environment

  3. Scaling, soil moisture and evapotranspiration in runoff models

    Science.gov (United States)

    Wood, Eric F.

    1993-01-01

    The effects of small-scale heterogeneity in land surface characteristics on the large-scale fluxes of water and energy in the land-atmosphere system has become a central focus of many of the climatology research experiments. The acquisition of high resolution land surface data through remote sensing and intensive land-climatology field experiments (like HAPEX and FIFE) has provided data to investigate the interactions between microscale land-atmosphere interactions and macroscale models. One essential research question is how to account for the small scale heterogeneities and whether 'effective' parameters can be used in the macroscale models. To address this question of scaling, the probability distribution for evaporation is derived which illustrates the conditions for which scaling should work. A correction algorithm that may appropriate for the land parameterization of a GCM is derived using a 2nd order linearization scheme. The performance of the algorithm is evaluated.

  4. Properties of Brownian Image Models in Scale-Space

    DEFF Research Database (Denmark)

    Pedersen, Kim Steenstrup

    2003-01-01

    Brownian images) will be discussed in relation to linear scale-space theory, and it will be shown empirically that the second order statistics of natural images mapped into jet space may, within some scale interval, be modeled by the Brownian image model. This is consistent with the 1/f 2 power spectrum...... law that apparently governs natural images. Furthermore, the distribution of Brownian images mapped into jet space is Gaussian and an analytical expression can be derived for the covariance matrix of Brownian images in jet space. This matrix is also a good approximation of the covariance matrix......In this paper it is argued that the Brownian image model is the least committed, scale invariant, statistical image model which describes the second order statistics of natural images. Various properties of three different types of Gaussian image models (white noise, Brownian and fractional...

  5. Nucleon electric dipole moments in high-scale supersymmetric models

    International Nuclear Information System (INIS)

    Hisano, Junji; Kobayashi, Daiki; Kuramoto, Wataru; Kuwahara, Takumi

    2015-01-01

    The electric dipole moments (EDMs) of electron and nucleons are promising probes of the new physics. In generic high-scale supersymmetric (SUSY) scenarios such as models based on mixture of the anomaly and gauge mediations, gluino has an additional contribution to the nucleon EDMs. In this paper, we studied the effect of the CP-violating gluon Weinberg operator induced by the gluino chromoelectric dipole moment in the high-scale SUSY scenarios, and we evaluated the nucleon and electron EDMs in the scenarios. We found that in the generic high-scale SUSY models, the nucleon EDMs may receive the sizable contribution from the Weinberg operator. Thus, it is important to compare the nucleon EDMs with the electron one in order to discriminate among the high-scale SUSY models.

  6. Nucleon electric dipole moments in high-scale supersymmetric models

    Energy Technology Data Exchange (ETDEWEB)

    Hisano, Junji [Kobayashi-Maskawa Institute for the Origin of Particles and the Universe (KMI),Nagoya University,Nagoya 464-8602 (Japan); Department of Physics, Nagoya University,Nagoya 464-8602 (Japan); Kavli IPMU (WPI), UTIAS, University of Tokyo,Kashiwa, Chiba 277-8584 (Japan); Kobayashi, Daiki; Kuramoto, Wataru; Kuwahara, Takumi [Department of Physics, Nagoya University,Nagoya 464-8602 (Japan)

    2015-11-12

    The electric dipole moments (EDMs) of electron and nucleons are promising probes of the new physics. In generic high-scale supersymmetric (SUSY) scenarios such as models based on mixture of the anomaly and gauge mediations, gluino has an additional contribution to the nucleon EDMs. In this paper, we studied the effect of the CP-violating gluon Weinberg operator induced by the gluino chromoelectric dipole moment in the high-scale SUSY scenarios, and we evaluated the nucleon and electron EDMs in the scenarios. We found that in the generic high-scale SUSY models, the nucleon EDMs may receive the sizable contribution from the Weinberg operator. Thus, it is important to compare the nucleon EDMs with the electron one in order to discriminate among the high-scale SUSY models.

  7. New phenomena in the standard no-scale supergravity model

    CERN Document Server

    Kelley, S; Nanopoulos, Dimitri V; Zichichi, Antonino; Kelley, S; Lopez, J L; Nanopoulos, D V; Zichichi, A

    1994-01-01

    We revisit the no-scale mechanism in the context of the simplest no-scale supergravity extension of the Standard Model. This model has the usual five-dimensional parameter space plus an additional parameter \\xi_{3/2}\\equiv m_{3/2}/m_{1/2}. We show how predictions of the model may be extracted over the whole parameter space. A necessary condition for the potential to be stable is {\\rm Str}{\\cal M}^4>0, which is satisfied if \\bf m_{3/2}\\lsim2 m_{\\tilde q}. Order of magnitude calculations reveal a no-lose theorem guaranteeing interesting and potentially observable new phenomena in the neutral scalar sector of the theory which would constitute a ``smoking gun'' of the no-scale mechanism. This new phenomenology is model-independent and divides into three scenarios, depending on the ratio of the weak scale to the vev at the minimum of the no-scale direction. We also calculate the residual vacuum energy at the unification scale (C_0\\, m^4_{3/2}), and find that in typical models one must require C_0>10. Such constrai...

  8. Toward micro-scale spatial modeling of gentrification

    Science.gov (United States)

    O'Sullivan, David

    A simple preliminary model of gentrification is presented. The model is based on an irregular cellular automaton architecture drawing on the concept of proximal space, which is well suited to the spatial externalities present in housing markets at the local scale. The rent gap hypothesis on which the model's cell transition rules are based is discussed. The model's transition rules are described in detail. Practical difficulties in configuring and initializing the model are described and its typical behavior reported. Prospects for further development of the model are discussed. The current model structure, while inadequate, is well suited to further elaboration and the incorporation of other interesting and relevant effects.

  9. Centralized vs. Decentralized Wage Formation: The Role of Firms' Production Technology

    OpenAIRE

    Hirsch, Boris; Merkl, Christian; Müller, Steffen; Schnabel, Claus

    2014-01-01

    This paper is the first to show theoretically and empirically how firms' production technology affects the choice of their preferred wage formation regime. Our theoretical framework predicts, first, that the larger the total factor productivity of a firm, the more likely it is to opt for centralized wage formation where it can hide behind less productive firms. Second, the larger a firm's scale elasticity, the higher its incentive to choose centralized rather than decentralized wage setting d...

  10. Gas at work. Vision on decentralized gas appliances in the built environment

    International Nuclear Information System (INIS)

    Van Gastel, M.; Hooijschuur, J.; De Jong, A.; De Visser, I.; Overdiep, H.; Bakker, E.J.; Van Wolferen, H.

    2008-04-01

    Various platforms operate within the SenterNovem programme Creative Energy. This report is the first version of the vision document of the working group Decentralized gas appliances of the Platform New Gas, in which the following aspects of the various promising innovative gas appliances are indicated: the development stage, the intended energy saving, the CO2 reduction, the bottlenecks for large scale market introduction and the solutions for these bottlenecks. [mk] [nl

  11. The ScaLIng Macroweather Model (SLIMM): using scaling to forecast global-scale macroweather from months to decades

    Science.gov (United States)

    Lovejoy, S.; del Rio Amador, L.; Hébert, R.

    2015-09-01

    On scales of ≈ 10 days (the lifetime of planetary-scale structures), there is a drastic transition from high-frequency weather to low-frequency macroweather. This scale is close to the predictability limits of deterministic atmospheric models; thus, in GCM (general circulation model) macroweather forecasts, the weather is a high-frequency noise. However, neither the GCM noise nor the GCM climate is fully realistic. In this paper we show how simple stochastic models can be developed that use empirical data to force the statistics and climate to be realistic so that even a two-parameter model can perform as well as GCMs for annual global temperature forecasts. The key is to exploit the scaling of the dynamics and the large stochastic memories that we quantify. Since macroweather temporal (but not spatial) intermittency is low, we propose using the simplest model based on fractional Gaussian noise (fGn): the ScaLIng Macroweather Model (SLIMM). SLIMM is based on a stochastic ordinary differential equation, differing from usual linear stochastic models (such as the linear inverse modelling - LIM) in that it is of fractional rather than integer order. Whereas LIM implicitly assumes that there is no low-frequency memory, SLIMM has a huge memory that can be exploited. Although the basic mathematical forecast problem for fGn has been solved, we approach the problem in an original manner, notably using the method of innovations to obtain simpler results on forecast skill and on the size of the effective system memory. A key to successful stochastic forecasts of natural macroweather variability is to first remove the low-frequency anthropogenic component. A previous attempt to use fGn for forecasts had disappointing results because this was not done. We validate our theory using hindcasts of global and Northern Hemisphere temperatures at monthly and annual resolutions. Several nondimensional measures of forecast skill - with no adjustable parameters - show excellent

  12. The Scaling LInear Macroweather model (SLIM): using scaling to forecast global scale macroweather from months to decades

    Science.gov (United States)

    Lovejoy, S.; del Rio Amador, L.; Hébert, R.

    2015-03-01

    At scales of ≈ 10 days (the lifetime of planetary scale structures), there is a drastic transition from high frequency weather to low frequency macroweather. This scale is close to the predictability limits of deterministic atmospheric models; so that in GCM macroweather forecasts, the weather is a high frequency noise. But neither the GCM noise nor the GCM climate is fully realistic. In this paper we show how simple stochastic models can be developped that use empirical data to force the statistics and climate to be realistic so that even a two parameter model can outperform GCM's for annual global temperature forecasts. The key is to exploit the scaling of the dynamics and the enormous stochastic memories that it implies. Since macroweather intermittency is low, we propose using the simplest model based on fractional Gaussian noise (fGn): the Scaling LInear Macroweather model (SLIM). SLIM is based on a stochastic ordinary differential equations, differing from usual linear stochastic models (such as the Linear Inverse Modelling, LIM) in that it is of fractional rather than integer order. Whereas LIM implicitly assumes there is no low frequency memory, SLIM has a huge memory that can be exploited. Although the basic mathematical forecast problem for fGn has been solved, we approach the problem in an original manner notably using the method of innovations to obtain simpler results on forecast skill and on the size of the effective system memory. A key to successful forecasts of natural macroweather variability is to first remove the low frequency anthropogenic component. A previous attempt to use fGn for forecasts had poor results because this was not done. We validate our theory using hindcasts of global and Northern Hemisphere temperatures at monthly and annual resolutions. Several nondimensional measures of forecast skill - with no adjustable parameters - show excellent agreement with hindcasts and these show some skill even at decadal scales. We also compare

  13. Description of Muzzle Blast by Modified Ideal Scaling Models

    Directory of Open Access Journals (Sweden)

    Kevin S. Fansler

    1998-01-01

    Full Text Available Gun blast data from a large variety of weapons are scaled and presented for both the instantaneous energy release and the constant energy deposition rate models. For both ideal explosion models, similar amounts of data scatter occur for the peak overpressure but the instantaneous energy release model correlated the impulse data significantly better, particularly for the region in front of the gun. Two parameters that characterize gun blast are used in conjunction with the ideal scaling models to improve the data correlation. The gun-emptying parameter works particularly well with the instantaneous energy release model to improve data correlation. In particular, the impulse, especially in the forward direction of the gun, is correlated significantly better using the instantaneous energy release model coupled with the use of the gun-emptying parameter. The use of the Mach disc location parameter improves the correlation only marginally. A predictive model is obtained from the modified instantaneous energy release correlation.

  14. Modelling of evapotranspiration at field and landscape scales. Abstract

    DEFF Research Database (Denmark)

    Overgaard, Jesper; Butts, M.B.; Rosbjerg, Dan

    2002-01-01

    observations from a nearby weather station. Detailed land-use and soil maps were used to set up the model. Leaf area index was derived from NDVI (Normalized Difference Vegetation Index) images. To validate the model at field scale the simulated evapotranspiration rates were compared to eddy...

  15. Role of scaling in the statistical modelling of finance

    Indian Academy of Sciences (India)

    Modelling the evolution of a financial index as a stochastic process is a problem awaiting a full, satisfactory solution since it was first formulated by Bachelier in 1900. Here it is shown that the scaling with time of the return probability density function sampled from the historical series suggests a successful model.

  16. Dynamic Modeling, Optimization, and Advanced Control for Large Scale Biorefineries

    DEFF Research Database (Denmark)

    Prunescu, Remus Mihail

    with a complex conversion route. Computational fluid dynamics is used to model transport phenomena in large reactors capturing tank profiles, and delays due to plug flows. This work publishes for the first time demonstration scale real data for validation showing that the model library is suitable...

  17. Appropriatie spatial scales to achieve model output uncertainty goals

    NARCIS (Netherlands)

    Booij, Martijn J.; Melching, Charles S.; Chen, Xiaohong; Chen, Yongqin; Xia, Jun; Zhang, Hailun

    2008-01-01

    Appropriate spatial scales of hydrological variables were determined using an existing methodology based on a balance in uncertainties from model inputs and parameters extended with a criterion based on a maximum model output uncertainty. The original methodology uses different relationships between

  18. Development of the Artistic Supervision Model Scale (ASMS)

    Science.gov (United States)

    Kapusuzoglu, Saduman; Dilekci, Umit

    2017-01-01

    The purpose of the study is to develop the Artistic Supervision Model Scale in accordance with the perception of inspectors and the elementary and secondary school teachers on artistic supervision. The lack of a measuring instrument related to the model of artistic supervision in the field of literature reveals the necessity of such study. 290…

  19. Accounting for small scale heterogeneity in ecohydrologic watershed models

    Science.gov (United States)

    Burke, W.; Tague, C.

    2017-12-01

    Spatially distributed ecohydrologic models are inherently constrained by the spatial resolution of their smallest units, below which land and processes are assumed to be homogenous. At coarse scales, heterogeneity is often accounted for by computing store and fluxes of interest over a distribution of land cover types (or other sources of heterogeneity) within spatially explicit modeling units. However this approach ignores spatial organization and the lateral transfer of water and materials downslope. The challenge is to account both for the role of flow network topology and fine-scale heterogeneity. We present a new approach that defines two levels of spatial aggregation and that integrates spatially explicit network approach with a flexible representation of finer-scale aspatial heterogeneity. Critically, this solution does not simply increase the resolution of the smallest spatial unit, and so by comparison, results in improved computational efficiency. The approach is demonstrated by adapting Regional Hydro-Ecologic Simulation System (RHESSys), an ecohydrologic model widely used to simulate climate, land use, and land management impacts. We illustrate the utility of our approach by showing how the model can be used to better characterize forest thinning impacts on ecohydrology. Forest thinning is typically done at the scale of individual trees, and yet management responses of interest include impacts on watershed scale hydrology and on downslope riparian vegetation. Our approach allow us to characterize the variability in tree size/carbon reduction and water transfers between neighboring trees while still capturing hillslope to watershed scale effects, Our illustrative example demonstrates that accounting for these fine scale effects can substantially alter model estimates, in some cases shifting the impacts of thinning on downslope water availability from increases to decreases. We conclude by describing other use cases that may benefit from this approach

  20. Transdisciplinary application of the cross-scale resilience model

    Science.gov (United States)

    Sundstrom, Shana M.; Angeler, David G.; Garmestani, Ahjond S.; Garcia, Jorge H.; Allen, Craig R.

    2014-01-01

    The cross-scale resilience model was developed in ecology to explain the emergence of resilience from the distribution of ecological functions within and across scales, and as a tool to assess resilience. We propose that the model and the underlying discontinuity hypothesis are relevant to other complex adaptive systems, and can be used to identify and track changes in system parameters related to resilience. We explain the theory behind the cross-scale resilience model, review the cases where it has been applied to non-ecological systems, and discuss some examples of social-ecological, archaeological/ anthropological, and economic systems where a cross-scale resilience analysis could add a quantitative dimension to our current understanding of system dynamics and resilience. We argue that the scaling and diversity parameters suitable for a resilience analysis of ecological systems are appropriate for a broad suite of systems where non-normative quantitative assessments of resilience are desired. Our planet is currently characterized by fast environmental and social change, and the cross-scale resilience model has the potential to quantify resilience across many types of complex adaptive systems.

  1. Scale-free, axisymmetry galaxy models with little angular momentum

    International Nuclear Information System (INIS)

    Richstone, D.O.

    1980-01-01

    Two scale-free models of elliptical galaxies are constructed using a self-consistent field approach developed by Schwarschild. Both models have concentric, oblate spheroidal, equipotential surfaces, with a logarithmic potential dependence on central distance. The axial ratio of the equipotential surfaces is 4:3, and the extent ratio of density level surfaces id 2.5:1 (corresponding to an E6 galaxy). Each model satisfies the Poisson and steady state Boltzmann equaion for time scales of order 100 galactic years

  2. Drift-Scale Coupled Processes (DST and THC Seepage) Models

    International Nuclear Information System (INIS)

    Sonnenthale, E.

    2001-01-01

    The purpose of this Analysis/Model Report (AMR) is to document the Near-Field Environment (NFE) and Unsaturated Zone (UZ) models used to evaluate the potential effects of coupled thermal-hydrologic-chemical (THC) processes on unsaturated zone flow and transport. This is in accordance with the ''Technical Work Plan (TWP) for Unsaturated Zone Flow and Transport Process Model Report'', Addendum D, Attachment D-4 (Civilian Radioactive Waste Management System (CRWMS) Management and Operating Contractor (M and O) 2000 [1534471]) and ''Technical Work Plan for Nearfield Environment Thermal Analyses and Testing'' (CRWMS M and O 2000 [153309]). These models include the Drift Scale Test (DST) THC Model and several THC seepage models. These models provide the framework to evaluate THC coupled processes at the drift scale, predict flow and transport behavior for specified thermal loading conditions, and predict the chemistry of waters and gases entering potential waste-emplacement drifts. The intended use of this AMR is to provide input for the following: Performance Assessment (PA); Near-Field Environment (NFE) PMR; Abstraction of Drift-Scale Coupled Processes AMR (ANL-NBS-HS-000029); and UZ Flow and Transport Process Model Report (PMR). The work scope for this activity is presented in the TWPs cited above, and summarized as follows: Continue development of the repository drift-scale THC seepage model used in support of the TSPA in-drift geochemical model; incorporate heterogeneous fracture property realizations; study sensitivity of results to changes in input data and mineral assemblage; validate the DST model by comparison with field data; perform simulations to predict mineral dissolution and precipitation and their effects on fracture properties and chemistry of water (but not flow rates) that may seep into drifts; submit modeling results to the TDMS and document the models. The model development, input data, sensitivity and validation studies described in this AMR are

  3. Ionocovalency and Applications 1. Ionocovalency Model and Orbital Hybrid Scales

    Directory of Open Access Journals (Sweden)

    Yonghe Zhang

    2010-11-01

    Full Text Available Ionocovalency (IC, a quantitative dual nature of the atom, is defined and correlated with quantum-mechanical potential to describe quantitatively the dual properties of the bond. Orbiotal hybrid IC model scale, IC, and IC electronegativity scale, XIC, are proposed, wherein the ionicity and the covalent radius are determined by spectroscopy. Being composed of the ionic function I and the covalent function C, the model describes quantitatively the dual properties of bond strengths, charge density and ionic potential. Based on the atomic electron configuration and the various quantum-mechanical built-up dual parameters, the model formed a Dual Method of the multiple-functional prediction, which has much more versatile and exceptional applications than traditional electronegativity scales and molecular properties. Hydrogen has unconventional values of IC and XIC, lower than that of boron. The IC model can agree fairly well with the data of bond properties and satisfactorily explain chemical observations of elements throughout the Periodic Table.

  4. Macroeconomic aspects of decentralized electricity production

    International Nuclear Information System (INIS)

    Percebois, J.

    1991-01-01

    The development of decentralized electricity production should be viewed first and foremost as a means of adapting production resources to meet the needs of the users between 1995 and 1997. Consumer production and cogeneration are not, however, simply stopgap solutions operating on the fringe of electricity production. These methods serve to highlight a problem that has already been raised in the past: the real advantages and disadvantages of centralized systems managed by companies that exercise a virtual monopoly in either the public or private sector

  5. Drift-Scale Coupled Processes (DST and THC Seepage) Models

    International Nuclear Information System (INIS)

    Dixon, P.

    2004-01-01

    The purpose of this Model Report (REV02) is to document the unsaturated zone (UZ) models used to evaluate the potential effects of coupled thermal-hydrological-chemical (THC) processes on UZ flow and transport. This Model Report has been developed in accordance with the ''Technical Work Plan for: Performance Assessment Unsaturated Zone'' (Bechtel SAIC Company, LLC (BSC) 2002 [160819]). The technical work plan (TWP) describes planning information pertaining to the technical scope, content, and management of this Model Report in Section 1.12, Work Package AUZM08, ''Coupled Effects on Flow and Seepage''. The plan for validation of the models documented in this Model Report is given in Attachment I, Model Validation Plans, Section I-3-4, of the TWP. Except for variations in acceptance criteria (Section 4.2), there were no deviations from this TWP. This report was developed in accordance with AP-SIII.10Q, ''Models''. This Model Report documents the THC Seepage Model and the Drift Scale Test (DST) THC Model. The THC Seepage Model is a drift-scale process model for predicting the composition of gas and water that could enter waste emplacement drifts and the effects of mineral alteration on flow in rocks surrounding drifts. The DST THC model is a drift-scale process model relying on the same conceptual model and much of the same input data (i.e., physical, hydrological, thermodynamic, and kinetic) as the THC Seepage Model. The DST THC Model is the primary method for validating the THC Seepage Model. The DST THC Model compares predicted water and gas compositions, as well as mineral alteration patterns, with observed data from the DST. These models provide the framework to evaluate THC coupled processes at the drift scale, predict flow and transport behavior for specified thermal-loading conditions, and predict the evolution of mineral alteration and fluid chemistry around potential waste emplacement drifts. The DST THC Model is used solely for the validation of the THC

  6. Model Scaling of Hydrokinetic Ocean Renewable Energy Systems

    Science.gov (United States)

    von Ellenrieder, Karl; Valentine, William

    2013-11-01

    Numerical simulations are performed to validate a non-dimensional dynamic scaling procedure that can be applied to subsurface and deeply moored systems, such as hydrokinetic ocean renewable energy devices. The prototype systems are moored in water 400 m deep and include: subsurface spherical buoys moored in a shear current and excited by waves; an ocean current turbine excited by waves; and a deeply submerged spherical buoy in a shear current excited by strong current fluctuations. The corresponding model systems, which are scaled based on relative water depths of 10 m and 40 m, are also studied. For each case examined, the response of the model system closely matches the scaled response of the corresponding full-sized prototype system. The results suggest that laboratory-scale testing of complete ocean current renewable energy systems moored in a current is possible. This work was supported by the U.S. Southeast National Marine Renewable Energy Center (SNMREC).

  7. Scale modeling of reinforced concrete structures subjected to seismic loading

    International Nuclear Information System (INIS)

    Dove, R.C.

    1983-01-01

    Reinforced concrete, Category I structures are so large that the possibility of seismicly testing the prototype structures under controlled conditions is essentially nonexistent. However, experimental data, from which important structural properties can be determined and existing and new methods of seismic analysis benchmarked, are badly needed. As a result, seismic experiments on scaled models are of considerable interest. In this paper, the scaling laws are developed in some detail so that assumptions and choices based on judgement can be clearly recognized and their effects discussed. The scaling laws developed are then used to design a reinforced concrete model of a Category I structure. Finally, how scaling is effected by various types of damping (viscous, structural, and Coulomb) is discussed

  8. Empirical spatial econometric modelling of small scale neighbourhood

    Science.gov (United States)

    Gerkman, Linda

    2012-07-01

    The aim of the paper is to model small scale neighbourhood in a house price model by implementing the newest methodology in spatial econometrics. A common problem when modelling house prices is that in practice it is seldom possible to obtain all the desired variables. Especially variables capturing the small scale neighbourhood conditions are hard to find. If there are important explanatory variables missing from the model, the omitted variables are spatially autocorrelated and they are correlated with the explanatory variables included in the model, it can be shown that a spatial Durbin model is motivated. In the empirical application on new house price data from Helsinki in Finland, we find the motivation for a spatial Durbin model, we estimate the model and interpret the estimates for the summary measures of impacts. By the analysis we show that the model structure makes it possible to model and find small scale neighbourhood effects, when we know that they exist, but we are lacking proper variables to measure them.

  9. Quantum critical scaling of fidelity in BCS-like model

    International Nuclear Information System (INIS)

    Adamski, Mariusz; Jedrzejewski, Janusz; Krokhmalskii, Taras

    2013-01-01

    We study scaling of the ground-state fidelity in neighborhoods of quantum critical points in a model of interacting spinful fermions—a BCS-like model. Due to the exact diagonalizability of the model, in one and higher dimensions, scaling of the ground-state fidelity can be analyzed numerically with great accuracy, not only for small systems but also for macroscopic ones, together with the crossover region between them. Additionally, in the one-dimensional case we have been able to derive a number of analytical formulas for fidelity and show that they accurately fit our numerical results; these results are reported in the paper. Besides regular critical points and their neighborhoods, where well-known scaling laws are obeyed, there is the multicritical point and critical points in its proximity where anomalous scaling behavior is found. We also consider scaling of fidelity in neighborhoods of critical points where fidelity oscillates strongly as the system size or the chemical potential is varied. Our results for a one-dimensional version of a BCS-like model are compared with those obtained recently by Rams and Damski in similar studies of a quantum spin chain—an anisotropic XY model in a transverse magnetic field. (paper)

  10. Scale genesis and gravitational wave in a classically scale invariant extension of the standard model

    Energy Technology Data Exchange (ETDEWEB)

    Kubo, Jisuke [Institute for Theoretical Physics, Kanazawa University,Kanazawa 920-1192 (Japan); Yamada, Masatoshi [Department of Physics, Kyoto University,Kyoto 606-8502 (Japan); Institut für Theoretische Physik, Universität Heidelberg,Philosophenweg 16, 69120 Heidelberg (Germany)

    2016-12-01

    We assume that the origin of the electroweak (EW) scale is a gauge-invariant scalar-bilinear condensation in a strongly interacting non-abelian gauge sector, which is connected to the standard model via a Higgs portal coupling. The dynamical scale genesis appears as a phase transition at finite temperature, and it can produce a gravitational wave (GW) background in the early Universe. We find that the critical temperature of the scale phase transition lies above that of the EW phase transition and below few O(100) GeV and it is strongly first-order. We calculate the spectrum of the GW background and find the scale phase transition is strong enough that the GW background can be observed by DECIGO.

  11. Bayesian hierarchical model for large-scale covariance matrix estimation.

    Science.gov (United States)

    Zhu, Dongxiao; Hero, Alfred O

    2007-12-01

    Many bioinformatics problems implicitly depend on estimating large-scale covariance matrix. The traditional approaches tend to give rise to high variance and low accuracy due to "overfitting." We cast the large-scale covariance matrix estimation problem into the Bayesian hierarchical model framework, and introduce dependency between covariance parameters. We demonstrate the advantages of our approaches over the traditional approaches using simulations and OMICS data analysis.

  12. Anomalous scaling in an age-dependent branching model.

    Science.gov (United States)

    Keller-Schmidt, Stephanie; Tuğrul, Murat; Eguíluz, Víctor M; Hernández-García, Emilio; Klemm, Konstantin

    2015-02-01

    We introduce a one-parametric family of tree growth models, in which branching probabilities decrease with branch age τ as τ(-α). Depending on the exponent α, the scaling of tree depth with tree size n displays a transition between the logarithmic scaling of random trees and an algebraic growth. At the transition (α=1) tree depth grows as (logn)(2). This anomalous scaling is in good agreement with the trend observed in evolution of biological species, thus providing a theoretical support for age-dependent speciation and associating it to the occurrence of a critical point.

  13. Macro-scale turbulence modelling for flows in porous media

    International Nuclear Information System (INIS)

    Pinson, F.

    2006-03-01

    - This work deals with the macroscopic modeling of turbulence in porous media. It concerns heat exchangers, nuclear reactors as well as urban flows, etc. The objective of this study is to describe in an homogenized way, by the mean of a spatial average operator, turbulent flows in a solid matrix. In addition to this first operator, the use of a statistical average operator permits to handle the pseudo-aleatory character of turbulence. The successive application of both operators allows us to derive the balance equations of the kind of flows under study. Two major issues are then highlighted, the modeling of dispersion induced by the solid matrix and the turbulence modeling at a macroscopic scale (Reynolds tensor and turbulent dispersion). To this aim, we lean on the local modeling of turbulence and more precisely on the k - ε RANS models. The methodology of dispersion study, derived thanks to the volume averaging theory, is extended to turbulent flows. Its application includes the simulation, at a microscopic scale, of turbulent flows within a representative elementary volume of the porous media. Applied to channel flows, this analysis shows that even within the turbulent regime, dispersion remains one of the dominating phenomena within the macro-scale modeling framework. A two-scale analysis of the flow allows us to understand the dominating role of the drag force in the kinetic energy transfers between scales. Transfers between the mean part and the turbulent part of the flow are formally derived. This description significantly improves our understanding of the issue of macroscopic modeling of turbulence and leads us to define the sub-filter production and the wake dissipation. A f - f - w >f model is derived. It is based on three balance equations for the turbulent kinetic energy, the viscous dissipation and the wake dissipation. Furthermore, a dynamical predictor for the friction coefficient is proposed. This model is then successfully applied to the study of

  14. Decentralization : Local Partnerships for Health Services in the ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    However, the national decentralization program is having a hard time getting on track. In the face of day-to-day difficulties Zenü Network, a nongovernmental organization, would like to make a contribution to this social project. The Network would like to demonstrate that civil society can work with decentralized government ...

  15. Decentralized Budgeting: Getting the Most Out of Disbursements of Funds.

    Science.gov (United States)

    Jefferson, Anne L.

    1995-01-01

    Decentralizing educational budgets allows the disbursement of funds aimed at maximizing student development. Three strategies for decentralizing budgets are program budgeting, which eliminates line-item budgeting and allows administrators to address questions regarding the relative value of educational programs; zero-based budgeting, which allows…

  16. A Review of Characteristics and Experiences of Decentralization of Education

    Science.gov (United States)

    Mwinjuma, Juma Saidi; Kadir, Suhaida bte Abd.; Hamzah, Azimi; Basri, Ramli

    2015-01-01

    This paper scrutinizes decentralization of education with reference to some countries around the world. We consider discussion on decentralization to be complex, critical and broad question in the contemporary education planning, administration and politics of education reforms. Even though the debate on and implementation of decentralization…

  17. Decentralization : Local Partnerships for Health Services in the ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Cameroon, like most other sub-Saharan African countries, has adopted laws devolving various responsibilities to local administrations. In the local political discourse, decentralization is seen as bringing essential services closer to the users, especially those in greatest need. However, the national decentralization program ...

  18. Decentralization: A panacea for functional education and national ...

    African Journals Online (AJOL)

    Decentralization of power from the federal government to state and local governments is the way to go, especially in the management of our education system. Education can be best delivered at the state and local government levels. Decentralization of educational management in Nigeria will encourage creativity and ...

  19. On Deciding How to Decide: To Centralize or Decentralize.

    Science.gov (United States)

    Chaffee, Ellen Earle

    Issues concerning whether to centralize or decentralize decision-making are addressed, with applications for colleges. Centralization/decentralization (C/D) must be analyzed with reference to a particular decision. Three components of C/D are locus of authority, breadth of participation, and relative contribution by the decision-maker's staff. C/D…

  20. Centralization Versus Decentralization: A Location Analysis Approach for Librarians.

    Science.gov (United States)

    Shishko, Robert; Raffel, Jeffrey

    One of the questions that seems to perplex many university and special librarians is whether to move in the direction of centralizing or decentralizing the library's collections and facilities. Presented is a theoretical approach, employing location theory, to the library centralization-decentralization question. Location theory allows the analyst…

  1. Decentralized energy studies: compendium of international studies and research

    Energy Technology Data Exchange (ETDEWEB)

    Wallace, C.

    1980-03-01

    The purpose of the compendium is to provide information about research activities in decentralized energy systems to researchers, government officials, and interested citizens. The compendium lists and briefly describes a number of studies in other industrialized nations that involve decentralized energy systems. A contact person is given for each of the activities listed so that interested readers can obtain more information.

  2. Decentralized Consistency Checking in Cross-organizational Workflows

    NARCIS (Netherlands)

    Wombacher, Andreas

    Service Oriented Architectures facilitate loosely coupled composed services, which are established in a decentralized way. One challenge for such composed services is to guarantee consistency, i.e., deadlock-freeness. This paper presents a decentralized approach to consistency checking, which

  3. Multi Scale Models for Flexure Deformation in Sheet Metal Forming

    Directory of Open Access Journals (Sweden)

    Di Pasquale Edmondo

    2016-01-01

    Full Text Available This paper presents the application of multi scale techniques to the simulation of sheet metal forming using the one-step method. When a blank flows over the die radius, it undergoes a complex cycle of bending and unbending. First, we describe an original model for the prediction of residual plastic deformation and stresses in the blank section. This model, working on a scale about one hundred times smaller than the element size, has been implemented in SIMEX, one-step sheet metal forming simulation code. The utilisation of this multi-scale modeling technique improves greatly the accuracy of the solution. Finally, we discuss the implications of this analysis on the prediction of springback in metal forming.

  4. Scaling of Core Material in Rubble Mound Breakwater Model Tests

    DEFF Research Database (Denmark)

    Burcharth, H. F.; Liu, Z.; Troch, P.

    1999-01-01

    The permeability of the core material influences armour stability, wave run-up and wave overtopping. The main problem related to the scaling of core materials in models is that the hydraulic gradient and the pore velocity are varying in space and time. This makes it impossible to arrive at a fully...... correct scaling. The paper presents an empirical formula for the estimation of the wave induced pressure gradient in the core, based on measurements in models and a prototype. The formula, together with the Forchheimer equation can be used for the estimation of pore velocities in cores. The paper proposes...... that the diameter of the core material in models is chosen in such a way that the Froude scale law holds for a characteristic pore velocity. The characteristic pore velocity is chosen as the average velocity of a most critical area in the core with respect to porous flow. Finally the method is demonstrated...

  5. Decentralized adaptive control of manipulators - Theory, simulation, and experimentation

    Science.gov (United States)

    Seraji, Homayoun

    1989-01-01

    The author presents a simple decentralized adaptive-control scheme for multijoint robot manipulators based on the independent joint control concept. The control objective is to achieve accurate tracking of desired joint trajectories. The proposed control scheme does not use the complex manipulator dynamic model, and each joint is controlled simply by a PID (proportional-integral-derivative) feedback controller and a position-velocity-acceleration feedforward controller, both with adjustable gains. Simulation results are given for a two-link direct-drive manipulator under adaptive independent joint control. The results illustrate trajectory tracking under coupled dynamics and varying payload. The proposed scheme is implemented on a MicroVAX II computer for motion control of the three major joints of a PUMA 560 arm. Experimental results are presented to demonstrate that trajectory tracking is achieved despite coupled nonlinear joint dynamics.

  6. Tuberculosis control: decentralization, local planning and management specificities.

    Science.gov (United States)

    Trigueiro, Janaína Von Söhsten; Nogueira, Jordana de Almeida; de Sá, Lenilde Duarte; Palha, Pedro Fredemir; Villa, Tereza Cristina Scatena; Trigueiro, Débora Raquel Soares Guedes

    2011-01-01

    The goal was to analyze, according to the perception of health managers, the practices that guide tuberculosis control actions in cities in the metropolitan region of João Pessoa - PB, Brazil. This qualitative study involved eight professionals in management functions. Testimonies were collected through semi-structured interviews between May and June 2009 and organized through content analysis. Despite the acknowledged benefits of tuberculosis control action decentralization, local planning indicates the predominance of a bureaucratic model that is restricted to negotiation and supplies. Local programming is centered on the coordinator, which shows a command line and vertical management that lead to the fragmentation of the work process. Management action should follow an innovative and transformative route that surpasses bureaucratic barriers and faces the biggest challenge it is proposed: to balance professional interrelations with a view to improving health work performance.

  7. Validity of the Neuromuscular Recovery Scale: a measurement model approach.

    Science.gov (United States)

    Velozo, Craig; Moorhouse, Michael; Ardolino, Elizabeth; Lorenz, Doug; Suter, Sarah; Basso, D Michele; Behrman, Andrea L

    2015-08-01

    To determine how well the Neuromuscular Recovery Scale (NRS) items fit the Rasch, 1-parameter, partial-credit measurement model. Confirmatory factor analysis (CFA) and principal components analysis (PCA) of residuals were used to determine dimensionality. The Rasch, 1-parameter, partial-credit rating scale model was used to determine rating scale structure, person/item fit, point-measure item correlations, item discrimination, and measurement precision. Seven NeuroRecovery Network clinical sites. Outpatients (N=188) with spinal cord injury. Not applicable. NRS. While the NRS met 1 of 3 CFA criteria, the PCA revealed that the Rasch measurement dimension explained 76.9% of the variance. Ten of 11 items and 91% of the patients fit the Rasch model, with 9 of 11 items showing high discrimination. Sixty-nine percent of the ratings met criteria. The items showed a logical item-difficulty order, with Stand retraining as the easiest item and Walking as the most challenging item. The NRS showed no ceiling or floor effects and separated the sample into almost 5 statistically distinct strata; individuals with an American Spinal Injury Association Impairment Scale (AIS) D classification showed the most ability, and those with an AIS A classification showed the least ability. Items not meeting the rating scale criteria appear to be related to the low frequency counts. The NRS met many of the Rasch model criteria for construct validity. Copyright © 2015 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  8. Decentralization and Participatory Rural Development: A Literature Review

    Directory of Open Access Journals (Sweden)

    Muhammad Shakil Ahmad

    2011-12-01

    Full Text Available Most of the developing nations are still struggling for efficient use of their resources. In order to overcome physical and administrative constraints of the development, it is necessary to transfer the power from the central government to local authorities. Distribution of power from improves the management of resources and community participation which is considered key to sustainable development. Advocates of decentralization argue that decentralized government is source to improve community participation in rural development. Decentralized government is considered more responsive towards local needs and development of poor peoples. There are many obstacles to expand the citizen participation in rural areas. There are many approaches for participatory development but all have to face the same challenges. Current paper highlights the literature about Decentralization and participatory rural development. Concept and modalities of Decentralization, dimensions of participation, types of rural participation and obstacles to participation are also the part of this paper.

  9. A Network Contention Model for the Extreme-scale Simulator

    Energy Technology Data Exchange (ETDEWEB)

    Engelmann, Christian [ORNL; Naughton III, Thomas J [ORNL

    2015-01-01

    The Extreme-scale Simulator (xSim) is a performance investigation toolkit for high-performance computing (HPC) hardware/software co-design. It permits running a HPC application with millions of concurrent execution threads, while observing its performance in a simulated extreme-scale system. This paper details a newly developed network modeling feature for xSim, eliminating the shortcomings of the existing network modeling capabilities. The approach takes a different path for implementing network contention and bandwidth capacity modeling using a less synchronous and accurate enough model design. With the new network modeling feature, xSim is able to simulate on-chip and on-node networks with reasonable accuracy and overheads.

  10. Fusion-supported decentralized nuclear energy system

    International Nuclear Information System (INIS)

    Jassby, D.L.

    1979-04-01

    A decentralized nuclear energy system is proposed comprising mass-produced pressurized water reactors in the size range 10 to 300 MW (thermal), to be used for the production of process heat, space heat, and electricity in applications where petroleum and natural gas are presently used. Special attention is given to maximizing the refueling interval with no interim batch shuffling in order to minimize fuel transport, reactor downtime, and opportunity for fissile diversion. These objectives demand a substantial fissile enrichment (7 to 15%). The preferred fissile fuel is U-233, which offers an order of magnitude savings in ore requirements (compared with U-235 fuel), and whose higher conversion ratio in thermal reactors serves to extend the period of useful reactivity and relieve demand on the fissile breeding plants (compared with Pu-239 fuel). Application of the neutral-beam-driven tokamak fusion-neutron source to a U-233 breeding pilot plant is examined. This scheme can be extended in part to a decentralized fusion energy system, wherein remotely located large fusion reactors supply excess tritium to a distributed system of relatively small nonbreeding D-T reactors

  11. Use of genome-scale microbial models for metabolic engineering

    DEFF Research Database (Denmark)

    Patil, Kiran Raosaheb; Åkesson, M.; Nielsen, Jens

    2004-01-01

    Metabolic engineering serves as an integrated approach to design new cell factories by providing rational design procedures and valuable mathematical and experimental tools. Mathematical models have an important role for phenotypic analysis, but can also be used for the design of optimal metaboli...... network structures. The major challenge for metabolic engineering in the post-genomic era is to broaden its design methodologies to incorporate genome-scale biological data. Genome-scale stoichiometric models of microorganisms represent a first step in this direction....

  12. Wind Farm Wake Models From Full Scale Data

    DEFF Research Database (Denmark)

    Knudsen, Torben; Bak, Thomas

    2012-01-01

    This investigation is part of the EU FP7 project “Distributed Control of Large-Scale Offshore Wind Farms”. The overall goal in this project is to develop wind farm controllers giving power set points to individual turbines in the farm in order to minimise mechanical loads and optimise power. One...... on real full scale data. The modelling is based on so called effective wind speed. It is shown that there is a wake for a wind direction range of up to 20 degrees. Further, when accounting for the wind direction it is shown that the two model structures considered can both fit the experimental data...

  13. Ground-water solute transport modeling using a three-dimensional scaled model

    International Nuclear Information System (INIS)

    Crider, S.S.

    1987-01-01

    Scaled models are used extensively in current hydraulic research on sediment transport and solute dispersion in free surface flows (rivers, estuaries), but are neglected in current ground-water model research. Thus, an investigation was conducted to test the efficacy of a three-dimensional scaled model of solute transport in ground water. No previous results from such a model have been reported. Experiments performed on uniform scaled models indicated that some historical problems (e.g., construction and scaling difficulties; disproportionate capillary rise in model) were partly overcome by using simple model materials (sand, cement and water), by restricting model application to selective classes of problems, and by physically controlling the effect of the model capillary zone. Results from these tests were compared with mathematical models. Model scaling laws were derived for ground-water solute transport and used to build a three-dimensional scaled model of a ground-water tritium plume in a prototype aquifer on the Savannah River Plant near Aiken, South Carolina. Model results compared favorably with field data and with a numerical model. Scaled models are recommended as a useful additional tool for prediction of ground-water solute transport

  14. Centralized vs. decentralized nursing stations: effects on nurses' functional use of space and work environment.

    Science.gov (United States)

    Zborowsky, Terri; Bunker-Hellmich, Lou; Morelli, Agneta; O'Neill, Mike

    2010-01-01

    nursing stations exceeded recommended levels during all shifts. No significant differences were identified in nurses' perceptions of work control-demand-support in centralized and decentralized nursing station designs. The "hybrid" nursing design model in which decentralized nursing stations are coupled with centralized meeting rooms for consultation between staff members may strike a balance between the increase in computer duties and the ongoing need for communication and consultation that addresses the conflicting demands of technology and direct patient care.

  15. Atomic scale modelling of materials of the nuclear fuel cycle

    International Nuclear Information System (INIS)

    Bertolus, M.

    2011-10-01

    This document written to obtain the French accreditation to supervise research presents the research I conducted at CEA Cadarache since 1999 on the atomic scale modelling of non-metallic materials involved in the nuclear fuel cycle: host materials for radionuclides from nuclear waste (apatites), fuel (in particular uranium dioxide) and ceramic cladding materials (silicon carbide). These are complex materials at the frontier of modelling capabilities since they contain heavy elements (rare earths or actinides), exhibit complex structures or chemical compositions and/or are subjected to irradiation effects: creation of point defects and fission products, amorphization. The objective of my studies is to bring further insight into the physics and chemistry of the elementary processes involved using atomic scale modelling and its coupling with higher scale models and experimental studies. This work is organised in two parts: on the one hand the development, adaptation and implementation of atomic scale modelling methods and validation of the approximations used; on the other hand the application of these methods to the investigation of nuclear materials under irradiation. This document contains a synthesis of the studies performed, orientations for future research, a detailed resume and a list of publications and communications. (author)

  16. Spatiotemporal exploratory models for broad-scale survey data.

    Science.gov (United States)

    Fink, Daniel; Hochachka, Wesley M; Zuckerberg, Benjamin; Winkler, David W; Shaby, Ben; Munson, M Arthur; Hooker, Giles; Riedewald, Mirek; Sheldon, Daniel; Kelling, Steve

    2010-12-01

    The distributions of animal populations change and evolve through time. Migratory species exploit different habitats at different times of the year. Biotic and abiotic features that determine where a species lives vary due to natural and anthropogenic factors. This spatiotemporal variation needs to be accounted for in any modeling of species' distributions. In this paper we introduce a semiparametric model that provides a flexible framework for analyzing dynamic patterns of species occurrence and abundance from broad-scale survey data. The spatiotemporal exploratory model (STEM) adds essential spatiotemporal structure to existing techniques for developing species distribution models through a simple parametric structure without requiring a detailed understanding of the underlying dynamic processes. STEMs use a multi-scale strategy to differentiate between local and global-scale spatiotemporal structure. A user-specified species distribution model accounts for spatial and temporal patterning at the local level. These local patterns are then allowed to "scale up" via ensemble averaging to larger scales. This makes STEMs especially well suited for exploring distributional dynamics arising from a variety of processes. Using data from eBird, an online citizen science bird-monitoring project, we demonstrate that monthly changes in distribution of a migratory species, the Tree Swallow (Tachycineta bicolor), can be more accurately described with a STEM than a conventional bagged decision tree model in which spatiotemporal structure has not been imposed. We also demonstrate that there is no loss of model predictive power when a STEM is used to describe a spatiotemporal distribution with very little spatiotemporal variation; the distribution of a nonmigratory species, the Northern Cardinal (Cardinalis cardinalis).

  17. Scaling and percolation in the small-world network model

    Energy Technology Data Exchange (ETDEWEB)

    Newman, M. E. J. [Santa Fe Institute, 1399 Hyde Park Road, Santa Fe, New Mexico 87501 (United States); Watts, D. J. [Santa Fe Institute, 1399 Hyde Park Road, Santa Fe, New Mexico 87501 (United States)

    1999-12-01

    In this paper we study the small-world network model of Watts and Strogatz, which mimics some aspects of the structure of networks of social interactions. We argue that there is one nontrivial length-scale in the model, analogous to the correlation length in other systems, which is well-defined in the limit of infinite system size and which diverges continuously as the randomness in the network tends to zero, giving a normal critical point in this limit. This length-scale governs the crossover from large- to small-world behavior in the model, as well as the number of vertices in a neighborhood of given radius on the network. We derive the value of the single critical exponent controlling behavior in the critical region and the finite size scaling form for the average vertex-vertex distance on the network, and, using series expansion and Pade approximants, find an approximate analytic form for the scaling function. We calculate the effective dimension of small-world graphs and show that this dimension varies as a function of the length-scale on which it is measured, in a manner reminiscent of multifractals. We also study the problem of site percolation on small-world networks as a simple model of disease propagation, and derive an approximate expression for the percolation probability at which a giant component of connected vertices first forms (in epidemiological terms, the point at which an epidemic occurs). The typical cluster radius satisfies the expected finite size scaling form with a cluster size exponent close to that for a random graph. All our analytic results are confirmed by extensive numerical simulations of the model. (c) 1999 The American Physical Society.

  18. Scaling and percolation in the small-world network model

    International Nuclear Information System (INIS)

    Newman, M. E. J.; Watts, D. J.

    1999-01-01

    In this paper we study the small-world network model of Watts and Strogatz, which mimics some aspects of the structure of networks of social interactions. We argue that there is one nontrivial length-scale in the model, analogous to the correlation length in other systems, which is well-defined in the limit of infinite system size and which diverges continuously as the randomness in the network tends to zero, giving a normal critical point in this limit. This length-scale governs the crossover from large- to small-world behavior in the model, as well as the number of vertices in a neighborhood of given radius on the network. We derive the value of the single critical exponent controlling behavior in the critical region and the finite size scaling form for the average vertex-vertex distance on the network, and, using series expansion and Pade approximants, find an approximate analytic form for the scaling function. We calculate the effective dimension of small-world graphs and show that this dimension varies as a function of the length-scale on which it is measured, in a manner reminiscent of multifractals. We also study the problem of site percolation on small-world networks as a simple model of disease propagation, and derive an approximate expression for the percolation probability at which a giant component of connected vertices first forms (in epidemiological terms, the point at which an epidemic occurs). The typical cluster radius satisfies the expected finite size scaling form with a cluster size exponent close to that for a random graph. All our analytic results are confirmed by extensive numerical simulations of the model. (c) 1999 The American Physical Society

  19. Multilevel method for modeling large-scale networks.

    Energy Technology Data Exchange (ETDEWEB)

    Safro, I. M. (Mathematics and Computer Science)

    2012-02-24

    Understanding the behavior of real complex networks is of great theoretical and practical significance. It includes developing accurate artificial models whose topological properties are similar to the real networks, generating the artificial networks at different scales under special conditions, investigating a network dynamics, reconstructing missing data, predicting network response, detecting anomalies and other tasks. Network generation, reconstruction, and prediction of its future topology are central issues of this field. In this project, we address the questions related to the understanding of the network modeling, investigating its structure and properties, and generating artificial networks. Most of the modern network generation methods are based either on various random graph models (reinforced by a set of properties such as power law distribution of node degrees, graph diameter, and number of triangles) or on the principle of replicating an existing model with elements of randomization such as R-MAT generator and Kronecker product modeling. Hierarchical models operate at different levels of network hierarchy but with the same finest elements of the network. However, in many cases the methods that include randomization and replication elements on the finest relationships between network nodes and modeling that addresses the problem of preserving a set of simplified properties do not fit accurately enough the real networks. Among the unsatisfactory features are numerically inadequate results, non-stability of algorithms on real (artificial) data, that have been tested on artificial (real) data, and incorrect behavior at different scales. One reason is that randomization and replication of existing structures can create conflicts between fine and coarse scales of the real network geometry. Moreover, the randomization and satisfying of some attribute at the same time can abolish those topological attributes that have been undefined or hidden from

  20. Homogenization of Large-Scale Movement Models in Ecology

    Science.gov (United States)

    Garlick, M.J.; Powell, J.A.; Hooten, M.B.; McFarlane, L.R.

    2011-01-01

    A difficulty in using diffusion models to predict large scale animal population dispersal is that individuals move differently based on local information (as opposed to gradients) in differing habitat types. This can be accommodated by using ecological diffusion. However, real environments are often spatially complex, limiting application of a direct approach. Homogenization for partial differential equations has long been applied to Fickian diffusion (in which average individual movement is organized along gradients of habitat and population density). We derive a homogenization procedure for ecological diffusion and apply it to a simple model for chronic wasting disease in mule deer. Homogenization allows us to determine the impact of small scale (10-100 m) habitat variability on large scale (10-100 km) movement. The procedure generates asymptotic equations for solutions on the large scale with parameters defined by small-scale variation. The simplicity of this homogenization procedure is striking when compared to the multi-dimensional homogenization procedure for Fickian diffusion,and the method will be equally straightforward for more complex models. ?? 2010 Society for Mathematical Biology.

  1. [Mes differ by positioning: empirical testing of decentralized dynamics of the self].

    Science.gov (United States)

    Mizokami, Shinichi

    2013-10-01

    The present study empirically tested the conceptualization of the decentralized dynamics of the self proposed by Hermans & Kempen (1993), which they developed theoretically and from clinical cases, not from large samples of empirical data. They posited that worldviews and images of the self could vary by positioning even in the same individual, and denied that the ego was an omniscient entity that knew and controlled all aspects of the self (centralized ego). Study 1 tested their conceptualization empirically with 47 university students in an experimental group and 17 as a control group. The results showed that the scores on the Rosenberg's self-esteem scale and images of the Mes in the experimental group significantly varied by positioning, but those in the control group did not. Similar results were found in Study 2 with a sample of 120 university students. These results empirically supported the conceptualization of the decentralized dynamics of the self.

  2. Two-dimensional divertor modeling and scaling laws

    International Nuclear Information System (INIS)

    Catto, P.J.; Connor, J.W.; Knoll, D.A.

    1996-01-01

    Two-dimensional numerical models of divertors contain large numbers of dimensionless parameters that must be varied to investigate all operating regimes of interest. To simplify the task and gain insight into divertor operation, we employ similarity techniques to investigate whether model systems of equations plus boundary conditions in the steady state admit scaling transformations that lead to useful divertor similarity scaling laws. A short mean free path neutral-plasma model of the divertor region below the x-point is adopted in which all perpendicular transport is due to the neutrals. We illustrate how the results can be used to benchmark large computer simulations by employing a modified version of UEDGE which contains a neutral fluid model. (orig.)

  3. Active Learning of Classification Models with Likert-Scale Feedback.

    Science.gov (United States)

    Xue, Yanbing; Hauskrecht, Milos

    2017-01-01

    Annotation of classification data by humans can be a time-consuming and tedious process. Finding ways of reducing the annotation effort is critical for building the classification models in practice and for applying them to a variety of classification tasks. In this paper, we develop a new active learning framework that combines two strategies to reduce the annotation effort. First, it relies on label uncertainty information obtained from the human in terms of the Likert-scale feedback. Second, it uses active learning to annotate examples with the greatest expected change. We propose a Bayesian approach to calculate the expectation and an incremental SVM solver to reduce the time complexity of the solvers. We show the combination of our active learning strategy and the Likert-scale feedback can learn classification models more rapidly and with a smaller number of labeled instances than methods that rely on either Likert-scale labels or active learning alone.

  4. Decentralized Channel Decisions of Green Supply Chain in a Fuzzy Decision Making Environment

    Directory of Open Access Journals (Sweden)

    Shengju Sang

    2017-01-01

    Full Text Available This paper considers the greening policies in a decentralized channel between one manufacturer and one retailer in a fuzzy decision making environment. We consider the manufacturing cost and the parameters of demand function as the fuzzy variables. Based on the different market structures, we develop three different fuzzy decentralized decision models. For each case, the expected value, optimistic value and pessimistic value models are formulated, and their optimal solutions are also derived through the fuzzy set theory. Finally, three numerical examples are solved to examine the effectiveness of fuzzy models. The effects of the confidence level of the supply chain memberrs profits and the fuzziness of parameters on optimal prices, level of green innovation, and fuzzy expected profits of actors are also analyzed.

  5. Multi-scale Modeling of Plasticity in Tantalum.

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Hojun [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Battaile, Corbett Chandler. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Carroll, Jay [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Buchheit, Thomas E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Boyce, Brad [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Weinberger, Christopher [Drexel Univ., Philadelphia, PA (United States)

    2015-12-01

    In this report, we present a multi-scale computational model to simulate plastic deformation of tantalum and validating experiments. In atomistic/ dislocation level, dislocation kink- pair theory is used to formulate temperature and strain rate dependent constitutive equations. The kink-pair theory is calibrated to available data from single crystal experiments to produce accurate and convenient constitutive laws. The model is then implemented into a BCC crystal plasticity finite element method (CP-FEM) model to predict temperature and strain rate dependent yield stresses of single and polycrystalline tantalum and compared with existing experimental data from the literature. Furthermore, classical continuum constitutive models describing temperature and strain rate dependent flow behaviors are fit to the yield stresses obtained from the CP-FEM polycrystal predictions. The model is then used to conduct hydro- dynamic simulations of Taylor cylinder impact test and compared with experiments. In order to validate the proposed tantalum CP-FEM model with experiments, we introduce a method for quantitative comparison of CP-FEM models with various experimental techniques. To mitigate the effects of unknown subsurface microstructure, tantalum tensile specimens with a pseudo-two-dimensional grain structure and grain sizes on the order of millimeters are used. A technique combining an electron back scatter diffraction (EBSD) and high resolution digital image correlation (HR-DIC) is used to measure the texture and sub-grain strain fields upon uniaxial tensile loading at various applied strains. Deformed specimens are also analyzed with optical profilometry measurements to obtain out-of- plane strain fields. These high resolution measurements are directly compared with large-scale CP-FEM predictions. This computational method directly links fundamental dislocation physics to plastic deformations in the grain-scale and to the engineering-scale applications. Furthermore, direct

  6. Exploiting multi-scale parallelism for large scale numerical modelling of laser wakefield accelerators

    International Nuclear Information System (INIS)

    Fonseca, R A; Vieira, J; Silva, L O; Fiuza, F; Davidson, A; Tsung, F S; Mori, W B

    2013-01-01

    A new generation of laser wakefield accelerators (LWFA), supported by the extreme accelerating fields generated in the interaction of PW-Class lasers and underdense targets, promises the production of high quality electron beams in short distances for multiple applications. Achieving this goal will rely heavily on numerical modelling to further understand the underlying physics and identify optimal regimes, but large scale modelling of these scenarios is computationally heavy and requires the efficient use of state-of-the-art petascale supercomputing systems. We discuss the main difficulties involved in running these simulations and the new developments implemented in the OSIRIS framework to address these issues, ranging from multi-dimensional dynamic load balancing and hybrid distributed/shared memory parallelism to the vectorization of the PIC algorithm. We present the results of the OASCR Joule Metric program on the issue of large scale modelling of LWFA, demonstrating speedups of over 1 order of magnitude on the same hardware. Finally, scalability to over ∼10 6 cores and sustained performance over ∼2 P Flops is demonstrated, opening the way for large scale modelling of LWFA scenarios. (paper)

  7. Optogenetic stimulation of a meso-scale human cortical model

    Science.gov (United States)

    Selvaraj, Prashanth; Szeri, Andrew; Sleigh, Jamie; Kirsch, Heidi

    2015-03-01

    Neurological phenomena like sleep and seizures depend not only on the activity of individual neurons, but on the dynamics of neuron populations as well. Meso-scale models of cortical activity provide a means to study neural dynamics at the level of neuron populations. Additionally, they offer a safe and economical way to test the effects and efficacy of stimulation techniques on the dynamics of the cortex. Here, we use a physiologically relevant meso-scale model of the cortex to study the hypersynchronous activity of neuron populations during epileptic seizures. The model consists of a set of stochastic, highly non-linear partial differential equations. Next, we use optogenetic stimulation to control seizures in a hyperexcited cortex, and to induce seizures in a normally functioning cortex. The high spatial and temporal resolution this method offers makes a strong case for the use of optogenetics in treating meso scale cortical disorders such as epileptic seizures. We use bifurcation analysis to investigate the effect of optogenetic stimulation in the meso scale model, and its efficacy in suppressing the non-linear dynamics of seizures.

  8. Small-Scale Helicopter Automatic Autorotation : Modeling, Guidance, and Control

    NARCIS (Netherlands)

    Taamallah, S.

    2015-01-01

    Our research objective consists in developing a, model-based, automatic safety recovery system, for a small-scale helicopter Unmanned Aerial Vehicle (UAV) in autorotation, i.e. an engine OFF flight condition, that safely flies and lands the helicopter to a pre-specified ground location. In pursuit

  9. Phenomenological aspects of no-scale inflation models

    Energy Technology Data Exchange (ETDEWEB)

    Ellis, John [Theoretical Particle Physics and Cosmology Group, Department of Physics,King’s College London,WC2R 2LS London (United Kingdom); Theory Division, CERN,CH-1211 Geneva 23 (Switzerland); Garcia, Marcos A.G. [William I. Fine Theoretical Physics Institute, School of Physics and Astronomy,University of Minnesota,116 Church Street SE, Minneapolis, MN 55455 (United States); Nanopoulos, Dimitri V. [George P. and Cynthia W. Mitchell Institute for Fundamental Physics andAstronomy, Texas A& M University,College Station, 77843 Texas (United States); Astroparticle Physics Group, Houston Advanced Research Center (HARC), Mitchell Campus, Woodlands, 77381 Texas (United States); Academy of Athens, Division of Natural Sciences, 28 Panepistimiou Avenue, 10679 Athens (Greece); Olive, Keith A. [William I. Fine Theoretical Physics Institute, School of Physics and Astronomy,University of Minnesota,116 Church Street SE, Minneapolis, MN 55455 (United States)

    2015-10-01

    We discuss phenomenological aspects of inflationary models wiith a no-scale supergravity Kähler potential motivated by compactified string models, in which the inflaton may be identified either as a Kähler modulus or an untwisted matter field, focusing on models that make predictions for the scalar spectral index n{sub s} and the tensor-to-scalar ratio r that are similar to the Starobinsky model. We discuss possible patterns of soft supersymmetry breaking, exhibiting examples of the pure no-scale type m{sub 0}=B{sub 0}=A{sub 0}=0, of the CMSSM type with universal A{sub 0} and m{sub 0}≠0 at a high scale, and of the mSUGRA type with A{sub 0}=B{sub 0}+m{sub 0} boundary conditions at the high input scale. These may be combined with a non-trivial gauge kinetic function that generates gaugino masses m{sub 1/2}≠0, or one may have a pure gravity mediation scenario where trilinear terms and gaugino masses are generated through anomalies. We also discuss inflaton decays and reheating, showing possible decay channels for the inflaton when it is either an untwisted matter field or a Kähler modulus. Reheating is very efficient if a matter field inflaton is directly coupled to MSSM fields, and both candidates lead to sufficient reheating in the presence of a non-trivial gauge kinetic function.

  10. Modeling and simulation in tribology across scales: An overview

    DEFF Research Database (Denmark)

    Vakis, A.I.; Yastrebov, V.A.; Scheibert, J.

    2018-01-01

    theories at the nano- and micro-scales, as well as multiscale and multiphysics aspects for analytical and computational models relevant to applications spanning a variety of sectors, from automotive to biotribology and nanotechnology. Significant effort is still required to account for complementary...

  11. Large scale solar district heating. Evaluation, modelling and designing - Appendices

    Energy Technology Data Exchange (ETDEWEB)

    Heller, A.

    2000-07-01

    The appendices present the following: A) Cad-drawing of the Marstal CSHP design. B) Key values - large-scale solar heating in Denmark. C) Monitoring - a system description. D) WMO-classification of pyranometers (solarimeters). E) The computer simulation model in TRNSYS. F) Selected papers from the author. (EHS)

  12. Vegetable parenting practices scale: Item response modeling analyses

    Science.gov (United States)

    Our objective was to evaluate the psychometric properties of a vegetable parenting practices scale using multidimensional polytomous item response modeling which enables assessing item fit to latent variables and the distributional characteristics of the items in comparison to the respondents. We al...

  13. Scale-invariant inclusive spectra in a dual model

    International Nuclear Information System (INIS)

    Chikovani, Z.E.; Jenkovsky, L.L.; Martynov, E.S.

    1979-01-01

    One-particle inclusive distributions at large transverse momentum phisub(tr) are shown to scale, Edσ/d 3 phi approximately phisub(tr)sup(-N)(1-Xsub(tr))sup(1+N/2)lnphisub(tr), in a dual model with Mandelstam analyticity if the Regge trajectories are logarithmic asymptotically

  14. Learning in an estimated medium-scale DSGE model

    Czech Academy of Sciences Publication Activity Database

    Slobodyan, Sergey; Wouters, R.

    2012-01-01

    Roč. 36, č. 1 (2012), s. 26-46 ISSN 0165-1889 R&D Projects: GA ČR(CZ) GCP402/11/J018 Institutional support: PRVOUK-P23 Keywords : constant-gain adaptive learning * medium-scale DSGE model * DSGE- VAR Subject RIV: AH - Economics Impact factor: 0.807, year: 2012

  15. Mountainous areas and decentralized energy planning: Insights from Greece

    International Nuclear Information System (INIS)

    Katsoulakos, Nikolas M.; Kaliampakos, Dimitris C.

    2016-01-01

    Mountainous areas have particular characteristics, whose influence on energy planning is explored in this paper, through a suitably tailored methodology applied to the case of Greece. The core element of the methodology is a linear optimization model with a “total cost” objective function, which includes financial, as well as external costs and benefits. Altitude proves to have decisive influence on energy optimization results, because it affects energy demand. The improvement of local energy systems provides greater socioeconomic benefits in mountainous settlements, due to the high shares of renewables and energy efficiency interventions in the optimal solutions. Energy poverty can be alleviated by redesigning local energy systems and the structure of the energy market. However, spatial and aesthetic restrictions, presented often in mountainous settlements, may affect the operational costs of energy systems, which is a crucial parameter for confronting energy poverty. Furthermore, the study indicates that it could be better to electrify remote areas, far from electricity grids, by decentralized systems than by grid expansion. The results of this study and the assumptions made about the way in which energy market should function, could be utilized for reconsidering energy policy measures, aiming at supporting sensitive societies to improve their development perspectives. - Highlights: •The influence of mountains' characteristics on energy planning was analyzed. •Optimal energy solutions present differentiations with respect to altitude. •Greater socioeconomic benefits by energy optimization in mountainous areas. •Remoteness favors the development of decentralized energy systems. •The study is based on data from Greece.

  16. Decentralized Biogas Technology of Anaerobic Digestion and Farm Ecosystem: Opportunities and Challenges

    International Nuclear Information System (INIS)

    Wang, Junye

    2014-01-01

    Long-term economic and environmental concerns have resulted in a great amount of research on renewable sources of biomass and bioenergy to replace fossil fuels in the past decades. Decentralized biogas technology is one of the most potential technologies of biomass and bioenergy by using agricultural waste materials (e.g., animal manure, crop straw, and by-products from food industries) as feedstocks. By-products from biogas production, called digestate, are nutrient rich, which could potentially be reused as green fertilizers in agriculture, thereby providing a sustainable substitute for synthetic fertilizers for farm ecosystem. Thus, the biogas production of anaerobic digestion is win–win option for livestock and crop producers to address issues of waste management and energy supply, and to avoid contamination of surface and ground waters and emissions of odors and greenhouse gases. In this paper, we review biogas production technology and then evaluate environmental effects of digestate used as fertilizer. Finally, we discuss issues of deployment of decentralized biogas technology for farm ecosystem. Economic and technological barriers still exist for large scale deployment of biogas technology in rural region. Two national scale deployments in China and Nepal showed that the operational status of biogas digesters is not optimal and up to 50% of plants are non-functional after a short operation period regardless of the social and economic factors. Main barriers are a wide variation of feedstocks and environmental conditions (e.g., temperature) over space and time. It becomes clear that the experimental conditions of the pilot plants need to be adjusted and calibrated to the local feedstocks and climate. Also, more research needs to be done in cold fermentation technology. Thus, collaboration of all relevant designers, farmers, stakeholders, and regulators is proposed as the way forward, particularly as their complexity has been identified as the major hurdle

  17. Decentralized Biogas Technology of Anaerobic Digestion and Farm Ecosystem: Opportunities and Challenges

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Junye, E-mail: junyew@athabascau.ca [Faculty of Science and Technology, Athabasca University, Athabasca, AB (Canada)

    2014-03-26

    Long-term economic and environmental concerns have resulted in a great amount of research on renewable sources of biomass and bioenergy to replace fossil fuels in the past decades. Decentralized biogas technology is one of the most potential technologies of biomass and bioenergy by using agricultural waste materials (e.g., animal manure, crop straw, and by-products from food industries) as feedstocks. By-products from biogas production, called digestate, are nutrient rich, which could potentially be reused as green fertilizers in agriculture, thereby providing a sustainable substitute for synthetic fertilizers for farm ecosystem. Thus, the biogas production of anaerobic digestion is win–win option for livestock and crop producers to address issues of waste management and energy supply, and to avoid contamination of surface and ground waters and emissions of odors and greenhouse gases. In this paper, we review biogas production technology and then evaluate environmental effects of digestate used as fertilizer. Finally, we discuss issues of deployment of decentralized biogas technology for farm ecosystem. Economic and technological barriers still exist for large scale deployment of biogas technology in rural region. Two national scale deployments in China and Nepal showed that the operational status of biogas digesters is not optimal and up to 50% of plants are non-functional after a short operation period regardless of the social and economic factors. Main barriers are a wide variation of feedstocks and environmental conditions (e.g., temperature) over space and time. It becomes clear that the experimental conditions of the pilot plants need to be adjusted and calibrated to the local feedstocks and climate. Also, more research needs to be done in cold fermentation technology. Thus, collaboration of all relevant designers, farmers, stakeholders, and regulators is proposed as the way forward, particularly as their complexity has been identified as the major hurdle

  18. Disappearing scales in carps: re-visiting Kirpichnikov's model on the genetics of scale pattern formation.

    Directory of Open Access Journals (Sweden)

    Laura Casas

    Full Text Available The body of most fishes is fully covered by scales that typically form tight, partially overlapping rows. While some of the genes controlling the formation and growth of fish scales have been studied, very little is known about the genetic mechanisms regulating scale pattern formation. Although the existence of two genes with two pairs of alleles (S&s and N&n regulating scale coverage in cyprinids has been predicted by Kirpichnikov and colleagues nearly eighty years ago, their identity was unknown until recently. In 2009, the 'S' gene was found to be a paralog of fibroblast growth factor receptor 1, fgfr1a1, while the second gene called 'N' has not yet been identified. We re-visited the original model of Kirpichnikov that proposed four major scale pattern types and observed a high degree of variation within the so-called scattered phenotype due to which this group was divided into two sub-types: classical mirror and irregular. We also analyzed the survival rates of offspring groups and found a distinct difference between Asian and European crosses. Whereas nude × nude crosses involving at least one parent of Asian origin or hybrid with Asian parent(s showed the 25% early lethality predicted by Kirpichnikov (due to the lethality of the NN genotype, those with two Hungarian nude parents did not. We further extended Kirpichnikov's work by correlating changes in phenotype (scale-pattern to the deformations of fins and losses of pharyngeal teeth. We observed phenotypic changes which were not restricted to nudes, as described by Kirpichnikov, but were also present in mirrors (and presumably in linears as well; not analyzed in detail here. We propose that the gradation of phenotypes observed within the scattered group is caused by a gradually decreasing level of signaling (a dose-dependent effect probably due to a concerted action of multiple pathways involved in scale formation.

  19. Disappearing scales in carps: Re-visiting Kirpichnikov's model on the genetics of scale pattern formation

    KAUST Repository

    Casas, Laura; Szűcs, Ré ka; Vij, Shubha; Goh, Chin Heng; Kathiresan, Purushothaman; Né meth, Sá ndor; Jeney, Zsigmond; Bercsé nyi, Mikló s; Orbá n, Lá szló

    2013-01-01

    The body of most fishes is fully covered by scales that typically form tight, partially overlapping rows. While some of the genes controlling the formation and growth of fish scales have been studied, very little is known about the genetic mechanisms regulating scale pattern formation. Although the existence of two genes with two pairs of alleles (S&s and N&n) regulating scale coverage in cyprinids has been predicted by Kirpichnikov and colleagues nearly eighty years ago, their identity was unknown until recently. In 2009, the 'S' gene was found to be a paralog of fibroblast growth factor receptor 1, fgfr1a1, while the second gene called 'N' has not yet been identified. We re-visited the original model of Kirpichnikov that proposed four major scale pattern types and observed a high degree of variation within the so-called scattered phenotype due to which this group was divided into two sub-types: classical mirror and irregular. We also analyzed the survival rates of offspring groups and found a distinct difference between Asian and European crosses. Whereas nude x nude crosses involving at least one parent of Asian origin or hybrid with Asian parent(s) showed the 25% early lethality predicted by Kirpichnikov (due to the lethality of the NN genotype), those with two Hungarian nude parents did not. We further extended Kirpichnikov's work by correlating changes in phenotype (scale-pattern) to the deformations of fins and losses of pharyngeal teeth. We observed phenotypic changes which were not restricted to nudes, as described by Kirpichnikov, but were also present in mirrors (and presumably in linears as well; not analyzed in detail here). We propose that the gradation of phenotypes observed within the scattered group is caused by a gradually decreasing level of signaling (a dosedependent effect) probably due to a concerted action of multiple pathways involved in scale formation. 2013 Casas et al.

  20. Disappearing scales in carps: Re-visiting Kirpichnikov's model on the genetics of scale pattern formation

    KAUST Repository

    Casas, Laura

    2013-12-30

    The body of most fishes is fully covered by scales that typically form tight, partially overlapping rows. While some of the genes controlling the formation and growth of fish scales have been studied, very little is known about the genetic mechanisms regulating scale pattern formation. Although the existence of two genes with two pairs of alleles (S&s and N&n) regulating scale coverage in cyprinids has been predicted by Kirpichnikov and colleagues nearly eighty years ago, their identity was unknown until recently. In 2009, the \\'S\\' gene was found to be a paralog of fibroblast growth factor receptor 1, fgfr1a1, while the second gene called \\'N\\' has not yet been identified. We re-visited the original model of Kirpichnikov that proposed four major scale pattern types and observed a high degree of variation within the so-called scattered phenotype due to which this group was divided into two sub-types: classical mirror and irregular. We also analyzed the survival rates of offspring groups and found a distinct difference between Asian and European crosses. Whereas nude x nude crosses involving at least one parent of Asian origin or hybrid with Asian parent(s) showed the 25% early lethality predicted by Kirpichnikov (due to the lethality of the NN genotype), those with two Hungarian nude parents did not. We further extended Kirpichnikov\\'s work by correlating changes in phenotype (scale-pattern) to the deformations of fins and losses of pharyngeal teeth. We observed phenotypic changes which were not restricted to nudes, as described by Kirpichnikov, but were also present in mirrors (and presumably in linears as well; not analyzed in detail here). We propose that the gradation of phenotypes observed within the scattered group is caused by a gradually decreasing level of signaling (a dosedependent effect) probably due to a concerted action of multiple pathways involved in scale formation. 2013 Casas et al.

  1. Including investment risk in large-scale power market models

    DEFF Research Database (Denmark)

    Lemming, Jørgen Kjærgaard; Meibom, P.

    2003-01-01

    Long-term energy market models can be used to examine investments in production technologies, however, with market liberalisation it is crucial that such models include investment risks and investor behaviour. This paper analyses how the effect of investment risk on production technology selection...... can be included in large-scale partial equilibrium models of the power market. The analyses are divided into a part about risk measures appropriate for power market investors and a more technical part about the combination of a risk-adjustment model and a partial-equilibrium model. To illustrate...... the analyses quantitatively, a framework based on an iterative interaction between the equilibrium model and a separate risk-adjustment module was constructed. To illustrate the features of the proposed modelling approach we examined how uncertainty in demand and variable costs affects the optimal choice...

  2. Application of physical scaling towards downscaling climate model precipitation data

    Science.gov (United States)

    Gaur, Abhishek; Simonovic, Slobodan P.

    2018-04-01

    Physical scaling (SP) method downscales climate model data to local or regional scales taking into consideration physical characteristics of the area under analysis. In this study, multiple SP method based models are tested for their effectiveness towards downscaling North American regional reanalysis (NARR) daily precipitation data. Model performance is compared with two state-of-the-art downscaling methods: statistical downscaling model (SDSM) and generalized linear modeling (GLM). The downscaled precipitation is evaluated with reference to recorded precipitation at 57 gauging stations located within the study region. The spatial and temporal robustness of the downscaling methods is evaluated using seven precipitation based indices. Results indicate that SP method-based models perform best in downscaling precipitation followed by GLM, followed by the SDSM model. Best performing models are thereafter used to downscale future precipitations made by three global circulation models (GCMs) following two emission scenarios: representative concentration pathway (RCP) 2.6 and RCP 8.5 over the twenty-first century. The downscaled future precipitation projections indicate an increase in mean and maximum precipitation intensity as well as a decrease in the total number of dry days. Further an increase in the frequency of short (1-day), moderately long (2-4 day), and long (more than 5-day) precipitation events is projected.

  3. Modelling Planck-scale Lorentz violation via analogue models

    International Nuclear Information System (INIS)

    Weinfurtner, Silke; Liberati, Stefano; Visser, Matt

    2006-01-01

    Astrophysical tests of Planck-suppressed Lorentz violations had been extensively studied in recent years and very stringent constraints have been obtained within the framework of effective field theory. There are however still some unresolved theoretical issues, in particular regarding the so called 'naturalness problem' - which arises when postulating that Planck suppressed Lorentz violations arise only from operators with mass dimension greater than four in the Lagrangian. In the work presented here we shall try to address this problem by looking at a condensed-matter analogue of the Lorentz violations considered in quantum gravity phenomenology. specifically, we investigate the class of two-component BECs subject to laserinduced transitions between the two components, and we show that this model is an example for Lorentz invariance violation due to ultraviolet physics. We shall show that such a model can be considered to be an explicit example high-energy Lorentz violations where the 'naturalness problem' does not arise

  4. Modeling and Simulation Techniques for Large-Scale Communications Modeling

    National Research Council Canada - National Science Library

    Webb, Steve

    1997-01-01

    .... Tests of random number generators were also developed and applied to CECOM models. It was found that synchronization of random number strings in simulations is easy to implement and can provide significant savings for making comparative studies. If synchronization is in place, then statistical experiment design can be used to provide information on the sensitivity of the output to input parameters. The report concludes with recommendations and an implementation plan.

  5. Drift-Scale Coupled Processes (DST and THC Seepage) Models

    Energy Technology Data Exchange (ETDEWEB)

    E. Gonnenthal; N. Spyoher

    2001-02-05

    The purpose of this Analysis/Model Report (AMR) is to document the Near-Field Environment (NFE) and Unsaturated Zone (UZ) models used to evaluate the potential effects of coupled thermal-hydrologic-chemical (THC) processes on unsaturated zone flow and transport. This is in accordance with the ''Technical Work Plan (TWP) for Unsaturated Zone Flow and Transport Process Model Report'', Addendum D, Attachment D-4 (Civilian Radioactive Waste Management System (CRWMS) Management and Operating Contractor (M and O) 2000 [153447]) and ''Technical Work Plan for Nearfield Environment Thermal Analyses and Testing'' (CRWMS M and O 2000 [153309]). These models include the Drift Scale Test (DST) THC Model and several THC seepage models. These models provide the framework to evaluate THC coupled processes at the drift scale, predict flow and transport behavior for specified thermal loading conditions, and predict the chemistry of waters and gases entering potential waste-emplacement drifts. The intended use of this AMR is to provide input for the following: (1) Performance Assessment (PA); (2) Abstraction of Drift-Scale Coupled Processes AMR (ANL-NBS-HS-000029); (3) UZ Flow and Transport Process Model Report (PMR); and (4) Near-Field Environment (NFE) PMR. The work scope for this activity is presented in the TWPs cited above, and summarized as follows: continue development of the repository drift-scale THC seepage model used in support of the TSPA in-drift geochemical model; incorporate heterogeneous fracture property realizations; study sensitivity of results to changes in input data and mineral assemblage; validate the DST model by comparison with field data; perform simulations to predict mineral dissolution and precipitation and their effects on fracture properties and chemistry of water (but not flow rates) that may seep into drifts; submit modeling results to the TDMS and document the models. The model development, input data

  6. New Models and Methods for the Electroweak Scale

    Energy Technology Data Exchange (ETDEWEB)

    Carpenter, Linda [The Ohio State Univ., Columbus, OH (United States). Dept. of Physics

    2017-09-26

    This is the Final Technical Report to the US Department of Energy for grant DE-SC0013529, New Models and Methods for the Electroweak Scale, covering the time period April 1, 2015 to March 31, 2017. The goal of this project was to maximize the understanding of fundamental weak scale physics in light of current experiments, mainly the ongoing run of the Large Hadron Collider and the space based satellite experiements searching for signals Dark Matter annihilation or decay. This research program focused on the phenomenology of supersymmetry, Higgs physics, and Dark Matter. The properties of the Higgs boson are currently being measured by the Large Hadron collider, and could be a sensitive window into new physics at the weak scale. Supersymmetry is the leading theoretical candidate to explain the natural nessof the electroweak theory, however new model space must be explored as the Large Hadron collider has disfavored much minimal model parameter space. In addition the nature of Dark Matter, the mysterious particle that makes up 25% of the mass of the universe is still unknown. This project sought to address measurements of the Higgs boson couplings to the Standard Model particles, new LHC discovery scenarios for supersymmetric particles, and new measurements of Dark Matter interactions with the Standard Model both in collider production and annihilation in space. Accomplishments include new creating tools for analyses of Dark Matter models in Dark Matter which annihilates into multiple Standard Model particles, including new visualizations of bounds for models with various Dark Matter branching ratios; benchmark studies for new discovery scenarios of Dark Matter at the Large Hardon Collider for Higgs-Dark Matter and gauge boson-Dark Matter interactions; New target analyses to detect direct decays of the Higgs boson into challenging final states like pairs of light jets, and new phenomenological analysis of non-minimal supersymmetric models, namely the set of Dirac

  7. Impact on continuity of care of decentralized versus partly centralized mental health care in Northern Norway

    Directory of Open Access Journals (Sweden)

    Lars Henrik Myklebust

    2011-12-01

    Full Text Available Background: The issue of continuity of care is central in contemporary psychiatric services research. In Norway, inpatient admissions are mainly to take place locally, in a system of small bed-units that represent an alternative to traditional central psychiatric hospitals. This type of organization may be advantageous for accessibility and cooperation, but has been given little scientific attention.Aims: To study whether inpatients' utilization of outpatient services differ between an area with a decentralized care model in comparison to an adjacent area with a partly centralized model.  Method: The study was based on data from a one-year registered prevalence sample, drawing on routinely sampled data supplemented with data from medical records. Service-utilization for 247 inpatients was analyzed. The results were controlled for diagnosis, demographic variables, type of service system, localization of inpatient admissions, and length of hospitalization. Results: Most inpatients in the area with the decentralized care model also utilized outpatient consultations, whereas a considerable number of inpatients in the area with a partly centralized model did not enter outpatient care at all. Type of service system, localization of inpatient admission, and length of hospitalization predicted inpatients' utilization of outpatient consultations. The results are discussed in the light of systems integration, particularly management-arrangements and clinical bridging over the transitional phase from inpatient to outpatient care. Conclusion: Inpatients' utilization of outpatient services differed between an area with a decentralized care model in comparison to an adjacent area with a partly centralized care model. In the areas studied, extensive decentralization of the psychiatric services positively affected coordination of inpatient and outpatient services for people with severe psychiatric disorders. Small, local-bed units may therefore represent a

  8. Impact on continuity of care of decentralized versus partly centralized mental health care in Northern Norway

    Directory of Open Access Journals (Sweden)

    Lars Henrik Myklebust

    2011-12-01

    Full Text Available Background: The issue of continuity of care is central in contemporary psychiatric services research. In Norway, inpatient admissions are mainly to take place locally, in a system of small bed-units that represent an alternative to traditional central psychiatric hospitals. This type of organization may be advantageous for accessibility and cooperation, but has been given little scientific attention. Aims: To study whether inpatients' utilization of outpatient services differ between an area with a decentralized care model in comparison to an adjacent area with a partly centralized model.   Method: The study was based on data from a one-year registered prevalence sample, drawing on routinely sampled data supplemented with data from medical records. Service-utilization for 247 inpatients was analyzed. The results were controlled for diagnosis, demographic variables, type of service system, localization of inpatient admissions, and length of hospitalization.  Results: Most inpatients in the area with the decentralized care model also utilized outpatient consultations, whereas a considerable number of inpatients in the area with a partly centralized model did not enter outpatient care at all. Type of service system, localization of inpatient admission, and length of hospitalization predicted inpatients' utilization of outpatient consultations. The results are discussed in the light of systems integration, particularly management-arrangements and clinical bridging over the transitional phase from inpatient to outpatient care.  Conclusion: Inpatients' utilization of outpatient services differed between an area with a decentralized care model in comparison to an adjacent area with a partly centralized care model. In the areas studied, extensive decentralization of the psychiatric services positively affected coordination of inpatient and outpatient services for people with severe psychiatric disorders. Small, local-bed units may therefore

  9. Impact on continuity of care of decentralized versus partly centralized mental health care in Northern Norway

    Science.gov (United States)

    Myklebust, Lars Henrik; Olstad, Reidun; Bjorbekkmo, Svein; Eisemann, Martin; Wynn, Rolf; Sørgaard, Knut

    2011-01-01

    Background The issue of continuity of care is central in contemporary psychiatric services research. In Norway, inpatient admissions are mainly to take place locally, in a system of small bed-units that represent an alternative to traditional central psychiatric hospitals. This type of organization may be advantageous for accessibility and cooperation, but has been given little scientific attention. Aims To study whether inpatients’ utilization of outpatient services differ between an area with a decentralized care model in comparison to an adjacent area with a partly centralized model. Method The study was based on data from a one-year registered prevalence sample, drawing on routinely sampled data supplemented with data from medical records. Service-utilization for 247 inpatients was analyzed. The results were controlled for diagnosis, demographic variables, type of service system, localization of inpatient admissions, and length of hospitalization. Results Most inpatients in the area with the decentralized care model also utilized outpatient consultations, whereas a considerable number of inpatients in the area with a partly centralized model did not enter outpatient care at all. Type of service system, localization of inpatient admission, and length of hospitalization predicted inpatients’ utilization of outpatient consultations. The results are discussed in the light of systems integration, particularly management-arrangements and clinical bridging over the transitional phase from inpatient to outpatient care. Conclusion Inpatients’ utilization of outpatient services differed between an area with a decentralized care model in comparison to an adjacent area with a partly centralized care model. In the areas studied, extensive decentralization of the psychiatric services positively affected coordination of inpatient and outpatient services for people with severe psychiatric disorders. Small, local-bed units may therefore represent a favourable alternative

  10. Retention in Differentiated Care: Multiple Measures Analysis for a Decentralized HIV Care and Treatment Program in North Central Nigeria

    Science.gov (United States)

    Agaba, Patricia A; Genberg, Becky L; Sagay, Atiene S; Agbaji, Oche O; Meloni, Seema T; Dadem, Nancin Y; Kolawole, Grace O; Okonkwo, Prosper; Kanki, Phyllis J; Ware, Norma C

    2018-01-01

    Objective Differentiated care refers collectively to flexible service models designed to meet the differing needs of HIV-infected persons in resource-scarce settings. Decentralization is one such service model. Retention is a key indicator for monitoring the success of HIV treatment and care programs. We used multiple measures to compare retention in a cohort of patients receiving HIV care at “hub” (central) and “spoke” (decentralized) sites in a large public HIV treatment program in north central Nigeria. Methods This retrospective cohort study utilized longitudinal program data representing central and decentralized levels of care in the Plateau State Decentralization Initiative, north central Nigeria. We examined retention with patient- level (retention at fixed times, loss-to-follow-up [LTFU]) and visit-level (gaps-in-care, visit constancy) measures. Regression models with generalized estimating equations (GEE) were used to estimate the effect of decentralization on visit-level measures. Patient-level measures were examined using survival methods with Cox regression models, controlling for baseline variables. Results Of 15,650 patients, 43% were enrolled at the hub. Median time in care was 3.1 years. Hub patients were less likely to be LTFU (adjusted hazard ratio (AHR)=0.91, 95% CI: 0.85-0.97), compared to spoke patients. Visit constancy was lower at the hub (−4.5%, 95% CI: −3.5, −5.5), where gaps in care were also more likely to occur (adjusted odds ratio=1.95, 95% CI: 1.83-2.08). Conclusion Decentralized sites demonstrated better retention outcomes using visit-level measures, while the hub achieved better retention outcomes using patient-level measures. Retention estimates produced by incorporating multiple measures showed substantial variation, confirming the influence of measurement strategies on the results of retention research. Future studies of retention in HIV care in sub-Saharan Africa will be well-served by including multiple measures

  11. Chemical theory and modelling through density across length scales

    International Nuclear Information System (INIS)

    Ghosh, Swapan K.

    2016-01-01

    One of the concepts that has played a major role in the conceptual as well as computational developments covering all the length scales of interest in a number of areas of chemistry, physics, chemical engineering and materials science is the concept of single-particle density. Density functional theory has been a versatile tool for the description of many-particle systems across length scales. Thus, in the microscopic length scale, an electron density based description has played a major role in providing a deeper understanding of chemical binding in atoms, molecules and solids. Density concept has been used in the form of single particle number density in the intermediate mesoscopic length scale to obtain an appropriate picture of the equilibrium and dynamical processes, dealing with a wide class of problems involving interfacial science and soft condensed matter. In the macroscopic length scale, however, matter is usually treated as a continuous medium and a description using local mass density, energy density and other related property density functions has been found to be quite appropriate. The basic ideas underlying the versatile uses of the concept of density in the theory and modelling of materials and phenomena, as visualized across length scales, along with selected illustrative applications to some recent areas of research on hydrogen energy, soft matter, nucleation phenomena, isotope separation, and separation of mixture in condensed phase, will form the subject matter of the talk. (author)

  12. Analysis for corruption and decentralization (Case study: earlier decentralization era in Indonesia)

    OpenAIRE

    Haryanto, Joko Tri; Astuti S.A., Esther Sri

    2017-01-01

    In many countries, relationship between decentralization of government activities and the extent of rent extraction by private parties is an important element in the recent debate on institutional design. The topic of corruption was actively, openly and debated in Indonesia by government, its development partners, and a broadly based group of political and civil society leaders are engaged in meetings and exchange on a daily basis. In the ongoing debate on corruption a lot of attention is pai...

  13. Extending SME to Handle Large-Scale Cognitive Modeling.

    Science.gov (United States)

    Forbus, Kenneth D; Ferguson, Ronald W; Lovett, Andrew; Gentner, Dedre

    2017-07-01

    Analogy and similarity are central phenomena in human cognition, involved in processes ranging from visual perception to conceptual change. To capture this centrality requires that a model of comparison must be able to integrate with other processes and handle the size and complexity of the representations required by the tasks being modeled. This paper describes extensions to Structure-Mapping Engine (SME) since its inception in 1986 that have increased its scope of operation. We first review the basic SME algorithm, describe psychological evidence for SME as a process model, and summarize its role in simulating similarity-based retrieval and generalization. Then we describe five techniques now incorporated into the SME that have enabled it to tackle large-scale modeling tasks: (a) Greedy merging rapidly constructs one or more best interpretations of a match in polynomial time: O(n 2 log(n)); (b) Incremental operation enables mappings to be extended as new information is retrieved or derived about the base or target, to model situations where information in a task is updated over time; (c) Ubiquitous predicates model the varying degrees to which items may suggest alignment; (d) Structural evaluation of analogical inferences models aspects of plausibility judgments; (e) Match filters enable large-scale task models to communicate constraints to SME to influence the mapping process. We illustrate via examples from published studies how these enable it to capture a broader range of psychological phenomena than before. Copyright © 2016 Cognitive Science Society, Inc.

  14. A Lagrangian dynamic subgrid-scale model turbulence

    Science.gov (United States)

    Meneveau, C.; Lund, T. S.; Cabot, W.

    1994-01-01

    A new formulation of the dynamic subgrid-scale model is tested in which the error associated with the Germano identity is minimized over flow pathlines rather than over directions of statistical homogeneity. This procedure allows the application of the dynamic model with averaging to flows in complex geometries that do not possess homogeneous directions. The characteristic Lagrangian time scale over which the averaging is performed is chosen such that the model is purely dissipative, guaranteeing numerical stability when coupled with the Smagorinsky model. The formulation is tested successfully in forced and decaying isotropic turbulence and in fully developed and transitional channel flow. In homogeneous flows, the results are similar to those of the volume-averaged dynamic model, while in channel flow, the predictions are superior to those of the plane-averaged dynamic model. The relationship between the averaged terms in the model and vortical structures (worms) that appear in the LES is investigated. Computational overhead is kept small (about 10 percent above the CPU requirements of the volume or plane-averaged dynamic model) by using an approximate scheme to advance the Lagrangian tracking through first-order Euler time integration and linear interpolation in space.

  15. Preparing the Model for Prediction Across Scales (MPAS) for global retrospective air quality modeling

    Science.gov (United States)

    The US EPA has a plan to leverage recent advances in meteorological modeling to develop a "Next-Generation" air quality modeling system that will allow consistent modeling of problems from global to local scale. The meteorological model of choice is the Model for Predic...

  16. Sensitivity, Error and Uncertainty Quantification: Interfacing Models at Different Scales

    International Nuclear Information System (INIS)

    Krstic, Predrag S.

    2014-01-01

    Discussion on accuracy of AMO data to be used in the plasma modeling codes for astrophysics and nuclear fusion applications, including plasma-material interfaces (PMI), involves many orders of magnitude of energy, spatial and temporal scales. Thus, energies run from tens of K to hundreds of millions of K, temporal and spatial scales go from fs to years and from nm’s to m’s and more, respectively. The key challenge for the theory and simulation in this field is the consistent integration of all processes and scales, i.e. an “integrated AMO science” (IAMO). The principal goal of the IAMO science is to enable accurate studies of interactions of electrons, atoms, molecules, photons, in many-body environment, including complex collision physics of plasma-material interfaces, leading to the best decisions and predictions. However, the accuracy requirement for a particular data strongly depends on the sensitivity of the respective plasma modeling applications to these data, which stresses a need for immediate sensitivity analysis feedback of the plasma modeling and material design communities. Thus, the data provision to the plasma modeling community is a “two-way road” as long as the accuracy of the data is considered, requiring close interactions of the AMO and plasma modeling communities.

  17. Modeling fast and slow earthquakes at various scales.

    Science.gov (United States)

    Ide, Satoshi

    2014-01-01

    Earthquake sources represent dynamic rupture within rocky materials at depth and often can be modeled as propagating shear slip controlled by friction laws. These laws provide boundary conditions on fault planes embedded in elastic media. Recent developments in observation networks, laboratory experiments, and methods of data analysis have expanded our knowledge of the physics of earthquakes. Newly discovered slow earthquakes are qualitatively different phenomena from ordinary fast earthquakes and provide independent information on slow deformation at depth. Many numerical simulations have been carried out to model both fast and slow earthquakes, but problems remain, especially with scaling laws. Some mechanisms are required to explain the power-law nature of earthquake rupture and the lack of characteristic length. Conceptual models that include a hierarchical structure over a wide range of scales would be helpful for characterizing diverse behavior in different seismic regions and for improving probabilistic forecasts of earthquakes.

  18. Testing of materials and scale models for impact limiters

    International Nuclear Information System (INIS)

    Maji, A.K.; Satpathi, D.; Schryer, H.L.

    1991-01-01

    Aluminum Honeycomb and Polyurethane foam specimens were tested to obtain experimental data on the material's behavior under different loading conditions. This paper reports the dynamic tests conducted on the materials and on the design and testing of scale models made out of these open-quotes Impact Limiters,close quotes as they are used in the design of transportation casks. Dynamic tests were conducted on a modified Charpy Impact machine with associated instrumentation, and compared with static test results. A scale model testing setup was designed and used for preliminary tests on models being used by current designers of transportation casks. The paper presents preliminary results of the program. Additional information will be available and reported at the time of presentation of the paper

  19. Coalescing colony model: Mean-field, scaling, and geometry

    Science.gov (United States)

    Carra, Giulia; Mallick, Kirone; Barthelemy, Marc

    2017-12-01

    We analyze the coalescing model where a `primary' colony grows and randomly emits secondary colonies that spread and eventually coalesce with it. This model describes population proliferation in theoretical ecology, tumor growth, and is also of great interest for modeling urban sprawl. Assuming the primary colony to be always circular of radius r (t ) and the emission rate proportional to r (t) θ , where θ >0 , we derive the mean-field equations governing the dynamics of the primary colony, calculate the scaling exponents versus θ , and compare our results with numerical simulations. We then critically test the validity of the circular approximation for the colony shape and show that it is sound for a constant emission rate (θ =0 ). However, when the emission rate is proportional to the perimeter, the circular approximation breaks down and the roughness of the primary colony cannot be discarded, thus modifying the scaling exponents.

  20. Lepton Dipole Moments in Supersymmetric Low-Scale Seesaw Models

    CERN Document Server

    Ilakovac, Amon; Popov, Luka

    2014-01-01

    We study the anomalous magnetic and electric dipole moments of charged leptons in supersymmetric low-scale seesaw models with right-handed neutrino superfields. We consider a minimally extended framework of minimal supergravity, by assuming that CP violation originates from complex soft SUSY-breaking bilinear and trilinear couplings associated with the right-handed sneutrino sector. We present numerical estimates of the muon anomalous magnetic moment and the electron electric dipole moment (EDM), as functions of key model parameters, such as the Majorana mass scale mN and tan(\\beta). In particular, we find that the contributions of the singlet heavy neutrinos and sneutrinos to the electron EDM are naturally small in this model, of order 10^{-27} - 10^{-28} e cm, and can be probed in the present and future experiments.

  1. Multiresolution comparison of precipitation datasets for large-scale models

    Science.gov (United States)

    Chun, K. P.; Sapriza Azuri, G.; Davison, B.; DeBeer, C. M.; Wheater, H. S.

    2014-12-01

    Gridded precipitation datasets are crucial for driving large-scale models which are related to weather forecast and climate research. However, the quality of precipitation products is usually validated individually. Comparisons between gridded precipitation products along with ground observations provide another avenue for investigating how the precipitation uncertainty would affect the performance of large-scale models. In this study, using data from a set of precipitation gauges over British Columbia and Alberta, we evaluate several widely used North America gridded products including the Canadian Gridded Precipitation Anomalies (CANGRD), the National Center for Environmental Prediction (NCEP) reanalysis, the Water and Global Change (WATCH) project, the thin plate spline smoothing algorithms (ANUSPLIN) and Canadian Precipitation Analysis (CaPA). Based on verification criteria for various temporal and spatial scales, results provide an assessment of possible applications for various precipitation datasets. For long-term climate variation studies (~100 years), CANGRD, NCEP, WATCH and ANUSPLIN have different comparative advantages in terms of their resolution and accuracy. For synoptic and mesoscale precipitation patterns, CaPA provides appealing performance of spatial coherence. In addition to the products comparison, various downscaling methods are also surveyed to explore new verification and bias-reduction methods for improving gridded precipitation outputs for large-scale models.

  2. Utilization of Large Scale Surface Models for Detailed Visibility Analyses

    Science.gov (United States)

    Caha, J.; Kačmařík, M.

    2017-11-01

    This article demonstrates utilization of large scale surface models with small spatial resolution and high accuracy, acquired from Unmanned Aerial Vehicle scanning, for visibility analyses. The importance of large scale data for visibility analyses on the local scale, where the detail of the surface model is the most defining factor, is described. The focus is not only the classic Boolean visibility, that is usually determined within GIS, but also on so called extended viewsheds that aims to provide more information about visibility. The case study with examples of visibility analyses was performed on river Opava, near the Ostrava city (Czech Republic). The multiple Boolean viewshed analysis and global horizon viewshed were calculated to determine most prominent features and visibility barriers of the surface. Besides that, the extended viewshed showing angle difference above the local horizon, which describes angular height of the target area above the barrier, is shown. The case study proved that large scale models are appropriate data source for visibility analyses on local level. The discussion summarizes possible future applications and further development directions of visibility analyses.

  3. Multi-scale climate modelling over Southern Africa using a variable-resolution global model

    CSIR Research Space (South Africa)

    Engelbrecht, FA

    2011-12-01

    Full Text Available -mail: fengelbrecht@csir.co.za Multi-scale climate modelling over Southern Africa using a variable-resolution global model FA Engelbrecht1, 2*, WA Landman1, 3, CJ Engelbrecht4, S Landman5, MM Bopape1, B Roux6, JL McGregor7 and M Thatcher7 1 CSIR Natural... improvement. Keywords: multi-scale climate modelling, variable-resolution atmospheric model Introduction Dynamic climate models have become the primary tools for the projection of future climate change, at both the global and regional scales. Dynamic...

  4. Performance prediction of industrial centrifuges using scale-down models.

    Science.gov (United States)

    Boychyn, M; Yim, S S S; Bulmer, M; More, J; Bracewell, D G; Hoare, M

    2004-12-01

    Computational fluid dynamics was used to model the high flow forces found in the feed zone of a multichamber-bowl centrifuge and reproduce these in a small, high-speed rotating disc device. Linking the device to scale-down centrifugation, permitted good estimation of the performance of various continuous-flow centrifuges (disc stack, multichamber bowl, CARR Powerfuge) for shear-sensitive protein precipitates. Critically, the ultra scale-down centrifugation process proved to be a much more accurate predictor of production multichamber-bowl performance than was the pilot centrifuge.

  5. Design and Modelling of Small Scale Low Temperature Power Cycles

    DEFF Research Database (Denmark)

    Wronski, Jorrit

    he work presented in this report contributes to the state of the art within design and modelling of small scale low temperature power cycles. The study is divided into three main parts: (i) fluid property evaluation, (ii) expansion device investigations and (iii) heat exchanger performance......-oriented Modelica code and was included in the thermo Cycle framework for small scale ORC systems. Special attention was paid to the valve system and a control method for variable expansion ratios was introduced based on a cogeneration scenario. Admission control based on evaporator and condenser conditions...

  6. Matrix models, Argyres-Douglas singularities and double scaling limits

    International Nuclear Information System (INIS)

    Bertoldi, Gaetano

    2003-01-01

    We construct an N = 1 theory with gauge group U(nN) and degree n+1 tree level superpotential whose matrix model spectral curve develops an Argyres-Douglas singularity. The calculation of the tension of domain walls in the U(nN) theory shows that the standard large-N expansion breaks down at the Argyres-Douglas points, with tension that scales as a fractional power of N. Nevertheless, it is possible to define appropriate double scaling limits which are conjectured to yield the tension of 2-branes in the resulting N = 1 four dimensional non-critical string theories as proposed by Ferrari. (author)

  7. Decentralized Coordinated Control Strategy of Islanded Microgrids

    DEFF Research Database (Denmark)

    Wu, Dan

    as grid voltage/frequency regulation. In order to enhance the reliability of overall islanded Microgrid operation, basic functions of coordinated control which taking into account the state of charge (SoC) limitation and power availability of renewable energy sources is implemented in a distributed level...... control strategies in this thesis, in order to promote the decentralization of the overall system. Especially the consensus algorithm based secondary level is investigated in the thesis in order to simplify the communication configuration which only flood information through the neighboring units......Facing the challenges brought by the traditional large power system concerning the environmental and economic issues, along recent years distributed generation is considered as an alternative solution to provide clean energy in a local manner. In this context, Microgrid which performing as a local...

  8. Vanuatu, the country of rural decentralized electrification

    International Nuclear Information System (INIS)

    Maigne, Y.; Molli, L.

    1998-01-01

    The status of decentralized rural electrification in Vanuatu was presented. Vanuatu is a sparsely populated rural country in the south Pacific. The country includes 92 populated islands spread over 1,000 kilometers in the south Pacific, halfway between Fiji and Australia. The low population density and the tremendous distances between the different islands have made local electrical networks a necessity in Vanuatu. Apart from the two principal urban centres, Vanuatu does not have a centralized electrical distribution network. In the early 1990s the government initiated a program to provide independent power sources to the isolated communities. Photovoltaic cells are used to power most telecommunications services. Solar cells are also used to provide power to important community buildings such as the schools or nursing stations on the remote islands. Two small hydroelectric generating stations of 600 kW were also installed with the help of the German government

  9. Fundamentals of the administrative decentralization process

    Directory of Open Access Journals (Sweden)

    Mihaela Lupăncescu

    2017-12-01

    Full Text Available Public administration, as an activity carried out by the administrative authorities, can be achieved through several forms of organization. In this sense, centralization, deconcentration and decentralization, together with its corollary, local autonomy, constitute in organizational regimes of an administrative nature, more or less democratic, and with characteristics that vary according to the degree of dependence between the authorities of the public administration institutions at the central level and local public administration authorities.There is no single form of organization that incorporates the characteristics of a particular regime. The complex expectations of modern society have led to the blending of features of different forms of organization in order to create a balance of activity within the public administration, in order to exercise the functions of executive power for the benefit of citizens, not by conferring unlimited autonomy but by considering the fundamental principle of legality.

  10. Decentralized energy supply on the liberalized market

    International Nuclear Information System (INIS)

    Pauli, H.

    1999-01-01

    Starting in 2001, the electricity market is to be progressively liberalized. The process will be completed by the year 2006. What role will decentralized power generation using combined cycle power plants play on a liberalized market ? The background conditions are essentially favourable: both the new energy act, which has been in force since 1 January 1999, and the planned energy levy suggest that this technology will become increasingly widespread. In addition, the price trend for combined cycle plants components together with low energy costs are having a favourable impact. On the other hand, great uncertainty is being created by the process of liberalization and the current flood of investments in power generation. However, electricity supply is unlikely to be in surplus for long in a context of sustained economic growth. (author)

  11. Centralized vs decentralized lunar power system study

    Science.gov (United States)

    Metcalf, Kenneth; Harty, Richard B.; Perronne, Gerald E.

    1991-09-01

    Three power-system options are considered with respect to utilization on a lunar base: the fully centralized option, the fully decentralized option, and a hybrid comprising features of the first two options. Power source, power conditioning, and power transmission are considered separately, and each architecture option is examined with ac and dc distribution, high and low voltage transmission, and buried and suspended cables. Assessments are made on the basis of mass, technological complexity, cost, reliability, and installation complexity, however, a preferred power-system architecture is not proposed. Preferred options include transmission based on ac, transmission voltages of 2000-7000 V with buried high-voltage lines and suspended low-voltage lines. Assessments of the total cost associated with the installations are required to determine the most suitable power system.

  12. Cross-Scale Modelling of Subduction from Minute to Million of Years Time Scale

    Science.gov (United States)

    Sobolev, S. V.; Muldashev, I. A.

    2015-12-01

    Subduction is an essentially multi-scale process with time-scales spanning from geological to earthquake scale with the seismic cycle in-between. Modelling of such process constitutes one of the largest challenges in geodynamic modelling today.Here we present a cross-scale thermomechanical model capable of simulating the entire subduction process from rupture (1 min) to geological time (millions of years) that employs elasticity, mineral-physics-constrained non-linear transient viscous rheology and rate-and-state friction plasticity. The model generates spontaneous earthquake sequences. The adaptive time-step algorithm recognizes moment of instability and drops the integration time step to its minimum value of 40 sec during the earthquake. The time step is then gradually increased to its maximal value of 5 yr, following decreasing displacement rates during the postseismic relaxation. Efficient implementation of numerical techniques allows long-term simulations with total time of millions of years. This technique allows to follow in details deformation process during the entire seismic cycle and multiple seismic cycles. We observe various deformation patterns during modelled seismic cycle that are consistent with surface GPS observations and demonstrate that, contrary to the conventional ideas, the postseismic deformation may be controlled by viscoelastic relaxation in the mantle wedge, starting within only a few hours after the great (M>9) earthquakes. Interestingly, in our model an average slip velocity at the fault closely follows hyperbolic decay law. In natural observations, such deformation is interpreted as an afterslip, while in our model it is caused by the viscoelastic relaxation of mantle wedge with viscosity strongly varying with time. We demonstrate that our results are consistent with the postseismic surface displacement after the Great Tohoku Earthquake for the day-to-year time range. We will also present results of the modeling of deformation of the

  13. Y-Scaling in a simple quark model

    International Nuclear Information System (INIS)

    Kumano, S.; Moniz, E.J.

    1988-01-01

    A simple quark model is used to define a nuclear pair model, that is, two composite hadrons interacting only through quark interchange and bound in an overall potential. An ''equivalent'' hadron model is developed, displaying an effective hadron-hadron interaction which is strongly repulsive. We compare the effective hadron model results with the exact quark model observables in the kinematic region of large momentum transfer, small energy transfer. The nucleon reponse function in this y-scaling region is, within the traditional frame work sensitive to the nucleon momentum distribution at large momentum. We find a surprizingly small effect of hadron substructure. Furthermore, we find in our model that a simple parametrization of modified hadron size in the bound state, motivated by the bound quark momentum distribution, is not a useful way to correlate different observables

  14. Site-scale groundwater flow modelling of Beberg

    Energy Technology Data Exchange (ETDEWEB)

    Gylling, B. [Kemakta Konsult AB, Stockholm (Sweden); Walker, D. [Duke Engineering and Services (United States); Hartley, L. [AEA Technology, Harwell (United Kingdom)

    1999-08-01

    The Swedish Nuclear Fuel and Waste Management Company (SKB) Safety Report for 1997 (SR 97) study is a comprehensive performance assessment illustrating the results for three hypothetical repositories in Sweden. In support of SR 97, this study examines the hydrogeologic modelling of the hypothetical site called Beberg, which adopts input parameters from the SKB study site near Finnsjoen, in central Sweden. This study uses a nested modelling approach, with a deterministic regional model providing boundary conditions to a site-scale stochastic continuum model. The model is run in Monte Carlo fashion to propagate the variability of the hydraulic conductivity to the advective travel paths from representative canister positions. A series of variant cases addresses uncertainties in the inference of parameters and the boundary conditions. The study uses HYDRASTAR, the SKB stochastic continuum (SC) groundwater modelling program, to compute the heads, Darcy velocities at each representative canister position, and the advective travel times and paths through the geosphere. The Base Case simulation takes its constant head boundary conditions from a modified version of the deterministic regional scale model of Hartley et al. The flow balance between the regional and site-scale models suggests that the nested modelling conserves mass only in a general sense, and that the upscaling is only approximately valid. The results for 100 realisation of 120 starting positions, a flow porosity of {epsilon}{sub f} 10{sup -4}, and a flow-wetted surface of a{sub r} = 1.0 m{sup 2}/(m{sup 3} rock) suggest the following statistics for the Base Case: The median travel time is 56 years. The median canister flux is 1.2 x 10{sup -3} m/year. The median F-ratio is 5.6 x 10{sup 5} year/m. The travel times, flow paths and exit locations were compatible with the observations on site, approximate scoping calculations and the results of related modelling studies. Variability within realisations indicates

  15. Hydrological Modelling of Small Scale Processes in a Wetland Habitat

    DEFF Research Database (Denmark)

    Johansen, Ole; Jensen, Jacob Birk; Pedersen, Morten Lauge

    2009-01-01

    Numerical modelling of the hydrology in a Danish rich fen area has been conducted. By collecting various data in the field the model has been successfully calibrated and the flow paths as well as the groundwater discharge distribution have been simulated in details. The results of this work have...... shown that distributed numerical models can be applied to local scale problems and that natural springs, ditches, the geological conditions as well as the local topographic variations have a significant influence on the flow paths in the examined rich fen area....

  16. Site-scale groundwater flow modelling of Beberg

    International Nuclear Information System (INIS)

    Gylling, B.; Walker, D.; Hartley, L.

    1999-08-01

    The Swedish Nuclear Fuel and Waste Management Company (SKB) Safety Report for 1997 (SR 97) study is a comprehensive performance assessment illustrating the results for three hypothetical repositories in Sweden. In support of SR 97, this study examines the hydrogeologic modelling of the hypothetical site called Beberg, which adopts input parameters from the SKB study site near Finnsjoen, in central Sweden. This study uses a nested modelling approach, with a deterministic regional model providing boundary conditions to a site-scale stochastic continuum model. The model is run in Monte Carlo fashion to propagate the variability of the hydraulic conductivity to the advective travel paths from representative canister positions. A series of variant cases addresses uncertainties in the inference of parameters and the boundary conditions. The study uses HYDRASTAR, the SKB stochastic continuum (SC) groundwater modelling program, to compute the heads, Darcy velocities at each representative canister position, and the advective travel times and paths through the geosphere. The Base Case simulation takes its constant head boundary conditions from a modified version of the deterministic regional scale model of Hartley et al. The flow balance between the regional and site-scale models suggests that the nested modelling conserves mass only in a general sense, and that the upscaling is only approximately valid. The results for 100 realisation of 120 starting positions, a flow porosity of ε f 10 -4 , and a flow-wetted surface of a r = 1.0 m 2 /(m 3 rock) suggest the following statistics for the Base Case: The median travel time is 56 years. The median canister flux is 1.2 x 10 -3 m/year. The median F-ratio is 5.6 x 10 5 year/m. The travel times, flow paths and exit locations were compatible with the observations on site, approximate scoping calculations and the results of related modelling studies. Variability within realisations indicates that the change in hydraulic gradient

  17. A No-Scale Inflationary Model to Fit Them All

    CERN Document Server

    Ellis, John; Nanopoulos, Dimitri; Olive, Keith

    2014-01-01

    The magnitude of B-mode polarization in the cosmic microwave background as measured by BICEP2 favours models of chaotic inflation with a quadratic $m^2 \\phi^2/2$ potential, whereas data from the Planck satellite favour a small value of the tensor-to-scalar perturbation ratio $r$ that is highly consistent with the Starobinsky $R + R^2$ model. Reality may lie somewhere between these two scenarios. In this paper we propose a minimal two-field no-scale supergravity model that interpolates between quadratic and Starobinsky-like inflation as limiting cases, while retaining the successful prediction $n_s \\simeq 0.96$.

  18. Influence of cardiac decentralization on cardioprotection.

    Directory of Open Access Journals (Sweden)

    John G Kingma

    Full Text Available The role of cardiac nerves on development of myocardial tissue injury after acute coronary occlusion remains controversial. We investigated whether acute cardiac decentralization (surgical modulates coronary flow reserve and myocardial protection in preconditioned dogs subject to ischemia-reperfusion. Experiments were conducted on four groups of anesthetised, open-chest dogs (n = 32: 1- controls (CTR, intact cardiac nerves, 2- ischemic preconditioning (PC; 4 cycles of 5-min IR, 3- cardiac decentralization (CD and 4- CD+PC; all dogs underwent 60-min coronary occlusion and 180-min reperfusion. Coronary blood flow and reactive hyperemic responses were assessed using a blood volume flow probe. Infarct size (tetrazolium staining was related to anatomic area at risk and coronary collateral blood flow (microspheres in the anatomic area at risk. Post-ischemic reactive hyperemia and repayment-to-debt ratio responses were significantly reduced for all experimental groups; however, arterial perfusion pressure was not affected. Infarct size was reduced in CD dogs (18.6 ± 4.3; p = 0.001, data are mean ± 1 SD compared to 25.2 ± 5.5% in CTR dogs and was less in PC dogs as expected (13.5 ± 3.2 vs. 25.2 ± 5.5%; p = 0.001; after acute CD, PC protection was conserved (11.6 ± 3.4 vs. 18.6 ± 4.3%; p = 0.02. In conclusion, our findings provide strong evidence that myocardial protection against ischemic injury can be preserved independent of extrinsic cardiac nerve inputs.

  19. A pragmatic approach to modelling soil and water conservation measures with a cathment scale erosion model.

    NARCIS (Netherlands)

    Hessel, R.; Tenge, A.J.M.

    2008-01-01

    To reduce soil erosion, soil and water conservation (SWC) methods are often used. However, no method exists to model beforehand how implementing such measures will affect erosion at catchment scale. A method was developed to simulate the effects of SWC measures with catchment scale erosion models.

  20. Micro perspectives for decentralized energy supply. Proceedings of the international conference

    Energy Technology Data Exchange (ETDEWEB)

    Schaefer, Martina; Kebir, Noara; Philipp, Daniel (eds.)

    2011-07-01

    Within the proceedings of the international conference at the Technical University Berlin (Berlin, Federal Republic of Germany) between 7th and 8th April, 2011 the following scientific papers were presented: (1) Renewables in residential development: An integrated GIS-based multicriteria approach for decentralized micro renewable energy production in new settlement development (C. Palmas); (2) Optimisation of off-grid-energy systems by combined use of renewable energy and storage devices (F. Huneke); (3) Decentralized electricity production from renewable sources as a chance for local economic development? Qualitative study of two pioneer regions in Germany (B. Klagge); (4) An analytical model for small-scale rural bioenergy systems (M. Gaul); (5) Reality check: Biomass as a fuel for small-scale electricity supply in developing countries (E. Dimpl v.L.); (6) Influential factors for the implementation of biogas plants in rural areas of Burkina Faso (A. Aschaber); (7) Policy and regulatory framework conditions for small hydro power in sub-saharian Africa (F. Koelling); (8) Current status of village level hydropower in eastern and southern Africa (W. Janker-Klunne), (9) Water desalination in micro grids based on renewable energies (K. Bognar); (10) The internal sphere of influence of peasant family farms in using biogas plants as part of sustainable development in rural areas of Germany (A. Bischoff); (11) A basic design for a multicriteria approach to efficient bioenergy production at regional level (Z. Hagen); (12) Ecological and economical evaluation of biogas feedstock from intercrops (N. Niemitz); (13) Energy recovery from sisal residues: A sustainable option for Tanzania? (J.C. Pfaff); (14) Opportunities and challenges for solar home systems in Tanzania for rural electrification (P.J. John); (15) The contribution of microenergy systems towards poverty reduction: Case study of an implementation strategy for solar home systems in Sri Lanka (D. Laufer); (16) Multi

  1. Responsiveness and flexibility in a Decentralized Supply Chain

    DEFF Research Database (Denmark)

    Petersen, Kristian Rasmus; Bilberg, Arne; Hadar, Ronen

    Today’s supply chains are not capable of managing the instabilities that is the case in the market. Instead, there is a need to develop supply chains that are capable of adapting to changes. Through a case study of LEGO, the authors suggest a possible solution: a decentralized supply chain serving...... independent and self-sufficient local factories. The decentralized supply chain is provided with materials, parts and pre-assembled elements from local suppliers and supplies the local market in return. Keywords: Decentralize, Responsiveness, Flexibility...

  2. Scaling analysis and model estimation of solar corona index

    Science.gov (United States)

    Ray, Samujjwal; Ray, Rajdeep; Khondekar, Mofazzal Hossain; Ghosh, Koushik

    2018-04-01

    A monthly average solar green coronal index time series for the period from January 1939 to December 2008 collected from NOAA (The National Oceanic and Atmospheric Administration) has been analysed in this paper in perspective of scaling analysis and modelling. Smoothed and de-noising have been done using suitable mother wavelet as a pre-requisite. The Finite Variance Scaling Method (FVSM), Higuchi method, rescaled range (R/S) and a generalized method have been applied to calculate the scaling exponents and fractal dimensions of the time series. Autocorrelation function (ACF) is used to find autoregressive (AR) process and Partial autocorrelation function (PACF) has been used to get the order of AR model. Finally a best fit model has been proposed using Yule-Walker Method with supporting results of goodness of fit and wavelet spectrum. The results reveal an anti-persistent, Short Range Dependent (SRD), self-similar property with signatures of non-causality, non-stationarity and nonlinearity in the data series. The model shows the best fit to the data under observation.

  3. A high-resolution global-scale groundwater model

    Science.gov (United States)

    de Graaf, I. E. M.; Sutanudjaja, E. H.; van Beek, L. P. H.; Bierkens, M. F. P.

    2015-02-01

    Groundwater is the world's largest accessible source of fresh water. It plays a vital role in satisfying basic needs for drinking water, agriculture and industrial activities. During times of drought groundwater sustains baseflow to rivers and wetlands, thereby supporting ecosystems. Most global-scale hydrological models (GHMs) do not include a groundwater flow component, mainly due to lack of geohydrological data at the global scale. For the simulation of lateral flow and groundwater head dynamics, a realistic physical representation of the groundwater system is needed, especially for GHMs that run at finer resolutions. In this study we present a global-scale groundwater model (run at 6' resolution) using MODFLOW to construct an equilibrium water table at its natural state as the result of long-term climatic forcing. The used aquifer schematization and properties are based on available global data sets of lithology and transmissivities combined with the estimated thickness of an upper, unconfined aquifer. This model is forced with outputs from the land-surface PCRaster Global Water Balance (PCR-GLOBWB) model, specifically net recharge and surface water levels. A sensitivity analysis, in which the model was run with various parameter settings, showed that variation in saturated conductivity has the largest impact on the groundwater levels simulated. Validation with observed groundwater heads showed that groundwater heads are reasonably well simulated for many regions of the world, especially for sediment basins (R2 = 0.95). The simulated regional-scale groundwater patterns and flow paths demonstrate the relevance of lateral groundwater flow in GHMs. Inter-basin groundwater flows can be a significant part of a basin's water budget and help to sustain river baseflows, especially during droughts. Also, water availability of larger aquifer systems can be positively affected by additional recharge from inter-basin groundwater flows.

  4. Using Scaling to Understand, Model and Predict Global Scale Anthropogenic and Natural Climate Change

    Science.gov (United States)

    Lovejoy, S.; del Rio Amador, L.

    2014-12-01

    The atmosphere is variable over twenty orders of magnitude in time (≈10-3 to 1017 s) and almost all of the variance is in the spectral "background" which we show can be divided into five scaling regimes: weather, macroweather, climate, macroclimate and megaclimate. We illustrate this with instrumental and paleo data. Based the signs of the fluctuation exponent H, we argue that while the weather is "what you get" (H>0: fluctuations increasing with scale), that it is macroweather (Hdecreasing with scale) - not climate - "that you expect". The conventional framework that treats the background as close to white noise and focuses on quasi-periodic variability assumes a spectrum that is in error by a factor of a quadrillion (≈ 1015). Using this scaling framework, we can quantify the natural variability, distinguish it from anthropogenic variability, test various statistical hypotheses and make stochastic climate forecasts. For example, we estimate the probability that the warming is simply a giant century long natural fluctuation is less than 1%, most likely less than 0.1% and estimate return periods for natural warming events of different strengths and durations, including the slow down ("pause") in the warming since 1998. The return period for the pause was found to be 20-50 years i.e. not very unusual; however it immediately follows a 6 year "pre-pause" warming event of almost the same magnitude with a similar return period (30 - 40 years). To improve on these unconditional estimates, we can use scaling models to exploit the long range memory of the climate process to make accurate stochastic forecasts of the climate including the pause. We illustrate stochastic forecasts on monthly and annual scale series of global and northern hemisphere surface temperatures. We obtain forecast skill nearly as high as the theoretical (scaling) predictability limits allow: for example, using hindcasts we find that at 10 year forecast horizons we can still explain ≈ 15% of the

  5. FROM CENTRALIZATION TO CRISIS DECENTRALIZATION IN PUBLIC ADMINISTRATION MANAGEMENT - AN EPISTEMOLOGICAL APPROACH

    OpenAIRE

    Petronela ZAHARIA

    2012-01-01

    The transition from centralization to decentralization has emerged as a necessity in managing the administrative system. Not a few are those who have focused to study this issue, investigating the main ideas expressed thus giving us the opportunity to shape an epistemological vision. We are strongly assured by the opinions expressed in this paper that the centralized model of organization does not meet the reformatory requirements of public administration. Following the same idea, the impleme...

  6. First Steps Towards Translating HZD Control of Bipedal Robots to Decentralized Control of Exoskeletons

    OpenAIRE

    Agrawal, Ayush; Harib, Omar; Hereid, Ayonga; Finet, Sylvain; Masselin, Matthieu; Praly, Laurent; Ames, Aaron D.; Sreenath, Koushil; Grizzle, Jessy W.

    2017-01-01

    This paper presents preliminary results toward translating gait and control design for bipedal robots to decentralized control of an exoskeleton aimed at restoring mobility to patients with lower limb paralysis, without the need for crutches. A mathematical hybrid dynamical model of the human-exoskeleton system is developed and a library of dynamically feasible periodic walking gaits for different walking speeds is found through nonlinear constrained optimization using the full-order dynamica...

  7. Modeling field scale unsaturated flow and transport processes

    International Nuclear Information System (INIS)

    Gelhar, L.W.; Celia, M.A.; McLaughlin, D.

    1994-08-01

    The scales of concern in subsurface transport of contaminants from low-level radioactive waste disposal facilities are in the range of 1 to 1,000 m. Natural geologic materials generally show very substantial spatial variability in hydraulic properties over this range of scales. Such heterogeneity can significantly influence the migration of contaminants. It is also envisioned that complex earth structures will be constructed to isolate the waste and minimize infiltration of water into the facility. The flow of water and gases through such facilities must also be a concern. A stochastic theory describing unsaturated flow and contamination transport in naturally heterogeneous soils has been enhanced by adopting a more realistic characterization of soil variability. The enhanced theory is used to predict field-scale effective properties and variances of tension and moisture content. Applications illustrate the important effects of small-scale heterogeneity on large-scale anisotropy and hysteresis and demonstrate the feasibility of simulating two-dimensional flow systems at time and space scales of interest in radioactive waste disposal investigations. Numerical algorithms for predicting field scale unsaturated flow and contaminant transport have been improved by requiring them to respect fundamental physical principles such as mass conservation. These algorithms are able to provide realistic simulations of systems with very dry initial conditions and high degrees of heterogeneity. Numerical simulation of the movement of water and air in unsaturated soils has demonstrated the importance of air pathways for contaminant transport. The stochastic flow and transport theory has been used to develop a systematic approach to performance assessment and site characterization. Hypothesis-testing techniques have been used to determine whether model predictions are consistent with observed data

  8. Non-linear scaling of a musculoskeletal model of the lower limb using statistical shape models.

    Science.gov (United States)

    Nolte, Daniel; Tsang, Chui Kit; Zhang, Kai Yu; Ding, Ziyun; Kedgley, Angela E; Bull, Anthony M J

    2016-10-03

    Accurate muscle geometry for musculoskeletal models is important to enable accurate subject-specific simulations. Commonly, linear scaling is used to obtain individualised muscle geometry. More advanced methods include non-linear scaling using segmented bone surfaces and manual or semi-automatic digitisation of muscle paths from medical images. In this study, a new scaling method combining non-linear scaling with reconstructions of bone surfaces using statistical shape modelling is presented. Statistical Shape Models (SSMs) of femur and tibia/fibula were used to reconstruct bone surfaces of nine subjects. Reference models were created by morphing manually digitised muscle paths to mean shapes of the SSMs using non-linear transformations and inter-subject variability was calculated. Subject-specific models of muscle attachment and via points were created from three reference models. The accuracy was evaluated by calculating the differences between the scaled and manually digitised models. The points defining the muscle paths showed large inter-subject variability at the thigh and shank - up to 26mm; this was found to limit the accuracy of all studied scaling methods. Errors for the subject-specific muscle point reconstructions of the thigh could be decreased by 9% to 20% by using the non-linear scaling compared to a typical linear scaling method. We conclude that the proposed non-linear scaling method is more accurate than linear scaling methods. Thus, when combined with the ability to reconstruct bone surfaces from incomplete or scattered geometry data using statistical shape models our proposed method is an alternative to linear scaling methods. Copyright © 2016 The Author. Published by Elsevier Ltd.. All rights reserved.

  9. (DeCentralization of Public Procurement at the Local Level in the EU

    Directory of Open Access Journals (Sweden)

    Boštjan BREZOVNIK

    2015-10-01

    Full Text Available The so-called decentralization of public procurement in EU Member States is accepted as the most suitable design of the public procurement system, often justifi ed by greater economic effi ciency and by the possibility of boosting the development of small and medium-sized enterprises, which act on the public procurement market as providers of goods, services and works. Despite the existence of highly decentralized public procurement systems which refl ect the decentralization of administrative systems, especially after the recession, there is a stronger tendency for centralization of public procurement in the EU. The so-called aggregation of demand by contracting authorities can be done in order to achieve economies of scale, including lower prices and transaction costs as well as to improve and professionalize the management of procurement procedures (as highlighted in the Directive 2014/24/EU by the European Parliament and the EU Council. However, even in the context of public procurement centralization, local contracting authorities (i.e., public administration authorities and organizations in Member States should be provided with a suffi ciently wide range of possible (centralized organizational structures and contractual (vertical and horizontal public-public partnerships which will allow them to select the most suitable and most economically effective organizational structure for the execution of public procurement.

  10. A decentralized receptance-based damage detection strategy for wireless smart sensors

    International Nuclear Information System (INIS)

    Jang, Shinae; Spencer Jr, Billie F; Sim, Sung-Han

    2012-01-01

    Various structural health monitoring strategies have been proposed recently that can be implemented in the decentralized computing environment intrinsic to wireless smart sensor networks (WSSN). Many are based on changes in the experimentally determined flexibility matrix for the structure under consideration. However, the flexibility matrix contains only static information; much richer information is available by considering the dynamic flexibility, or receptance, of the structure. Recently, the stochastic dynamic damage locating vector (SDDLV) method was proposed based on changes of dynamic flexibility matrices employing centrally collected output-only measurements. This paper investigates the potential of the SDDLV method for implementation on a network of wireless smart sensors, where a decentralized, hierarchical, in-network processing approach is used to address issues of scalability of the SDDLV algorithm. Two approaches to aggregate results are proposed that provide robust estimates of damage locations. The efficacy of the developed strategy is first verified using wired sensors emulating a wireless sensor network. Subsequently, the decentralized damage detection strategy is implemented on MEMSIC’s Imote2 smart sensor platform and validated experimentally on a laboratory scale truss bridge. (paper)

  11. Mapping the potential for decentralized energy generation based on RES in Western Balkans

    Directory of Open Access Journals (Sweden)

    Schneider Daniel R.

    2007-01-01

    Full Text Available Although the countries of the Western Balkans are mostly electrified, there are still regions which do not have access to the electricity network or where the network capacity is insufficient. For the most part such areas are under special care of the state (i. e. underdeveloped, devastated by war, depopulated, on islands or in mountainous regions. Since the decentralized energy generation covers a broad range of technologies, including many renewable energy technologies that provide small-scale power at sites close to the users, such concept could be of interest for these locations. This paper identifies the areas in Western Balkans where such systems could be applied. Consideration is given to geographical locations as well as possible applications. Wind, hydro, solar photovoltaic, and biomass conversion systems were taken into consideration. Since the renewable energy sources data for Western Balkans region are rather scarce, the intention was to give a survey of the present situation and an estimate of future potential for decentralized energy generation based on renewable energy sources. The decentralized energy generation based on renewable energy sources in Western Balkans will find its niche easier for the users that will produce electricity for their own needs and for the users located in remote rural areas (off-grid applications.

  12. Towards modeling intergranular stress corrosion cracks on grain size scales

    International Nuclear Information System (INIS)

    Simonovski, Igor; Cizelj, Leon

    2012-01-01

    Highlights: ► Simulating the onset and propagation of intergranular cracking. ► Model based on the as-measured geometry and crystallographic orientations. ► Feasibility, performance of the proposed computational approach demonstrated. - Abstract: Development of advanced models at the grain size scales has so far been mostly limited to simulated geometry structures such as for example 3D Voronoi tessellations. The difficulty came from a lack of non-destructive techniques for measuring the microstructures. In this work a novel grain-size scale approach for modelling intergranular stress corrosion cracking based on as-measured 3D grain structure of a 400 μm stainless steel wire is presented. Grain topologies and crystallographic orientations are obtained using a diffraction contrast tomography, reconstructed within a detailed finite element model and coupled with advanced constitutive models for grains and grain boundaries. The wire is composed of 362 grains and over 1600 grain boundaries. Grain boundary damage initialization and early development is then explored for a number of cases, ranging from isotropic elasticity up to crystal plasticity constitutive laws for the bulk grain material. In all cases the grain boundaries are modeled using the cohesive zone approach. The feasibility of the approach is explored.

  13. Multi-scale modeling of the CD8 immune response

    Energy Technology Data Exchange (ETDEWEB)

    Barbarroux, Loic, E-mail: loic.barbarroux@doctorant.ec-lyon.fr [Inria, Université de Lyon, UMR 5208, Institut Camille Jordan (France); Ecole Centrale de Lyon, 36 avenue Guy de Collongue, 69134 Ecully (France); Michel, Philippe, E-mail: philippe.michel@ec-lyon.fr [Inria, Université de Lyon, UMR 5208, Institut Camille Jordan (France); Ecole Centrale de Lyon, 36 avenue Guy de Collongue, 69134 Ecully (France); Adimy, Mostafa, E-mail: mostafa.adimy@inria.fr [Inria, Université de Lyon, UMR 5208, Université Lyon 1, Institut Camille Jordan, 43 Bd. du 11 novembre 1918, F-69200 Villeurbanne Cedex (France); Crauste, Fabien, E-mail: crauste@math.univ-lyon1.fr [Inria, Université de Lyon, UMR 5208, Université Lyon 1, Institut Camille Jordan, 43 Bd. du 11 novembre 1918, F-69200 Villeurbanne Cedex (France)

    2016-06-08

    During the primary CD8 T-Cell immune response to an intracellular pathogen, CD8 T-Cells undergo exponential proliferation and continuous differentiation, acquiring cytotoxic capabilities to address the infection and memorize the corresponding antigen. After cleaning the organism, the only CD8 T-Cells left are antigen-specific memory cells whose role is to respond stronger and faster in case they are presented this very same antigen again. That is how vaccines work: a small quantity of a weakened pathogen is introduced in the organism to trigger the primary response, generating corresponding memory cells in the process, giving the organism a way to defend himself in case it encounters the same pathogen again. To investigate this process, we propose a non linear, multi-scale mathematical model of the CD8 T-Cells immune response due to vaccination using a maturity structured partial differential equation. At the intracellular scale, the level of expression of key proteins is modeled by a delay differential equation system, which gives the speeds of maturation for each cell. The population of cells is modeled by a maturity structured equation whose speeds are given by the intracellular model. We focus here on building the model, as well as its asymptotic study. Finally, we display numerical simulations showing the model can reproduce the biological dynamics of the cell population for both the primary response and the secondary responses.

  14. Site-scale groundwater flow modelling of Aberg

    Energy Technology Data Exchange (ETDEWEB)

    Walker, D. [Duke Engineering and Services (United States); Gylling, B. [Kemakta Konsult AB, Stockholm (Sweden)

    1998-12-01

    The Swedish Nuclear Fuel and Waste Management Company (SKB) SR 97 study is a comprehensive performance assessment illustrating the results for three hypothetical repositories in Sweden. In support of SR 97, this study examines the hydrogeologic modelling of the hypothetical site called Aberg, which adopts input parameters from the Aespoe Hard Rock Laboratory in southern Sweden. This study uses a nested modelling approach, with a deterministic regional model providing boundary conditions to a site-scale stochastic continuum model. The model is run in Monte Carlo fashion to propagate the variability of the hydraulic conductivity to the advective travel paths from representative canister locations. A series of variant cases addresses uncertainties in the inference of parameters and the boundary conditions. The study uses HYDRASTAR, the SKB stochastic continuum groundwater modelling program, to compute the heads, Darcy velocities at each representative canister position and the advective travel times and paths through the geosphere. The nested modelling approach and the scale dependency of hydraulic conductivity raise a number of questions regarding the regional to site-scale mass balance and the method`s self-consistency. The transfer of regional heads via constant head boundaries preserves the regional pattern recharge and discharge in the site-scale model, and the regional to site-scale mass balance is thought to be adequate. The upscaling method appears to be approximately self-consistent with respect to the median performance measures at various grid scales. A series of variant cases indicates that the study results are insensitive to alternative methods on transferring boundary conditions from the regional model to the site-scale model. The flow paths, travel times and simulated heads appear to be consistent with on-site observations and simple scoping calculations. The variabilities of the performance measures are quite high for the Base Case, but the

  15. Site-scale groundwater flow modelling of Aberg

    International Nuclear Information System (INIS)

    Walker, D.; Gylling, B.

    1998-12-01

    The Swedish Nuclear Fuel and Waste Management Company (SKB) SR 97 study is a comprehensive performance assessment illustrating the results for three hypothetical repositories in Sweden. In support of SR 97, this study examines the hydrogeologic modelling of the hypothetical site called Aberg, which adopts input parameters from the Aespoe Hard Rock Laboratory in southern Sweden. This study uses a nested modelling approach, with a deterministic regional model providing boundary conditions to a site-scale stochastic continuum model. The model is run in Monte Carlo fashion to propagate the variability of the hydraulic conductivity to the advective travel paths from representative canister locations. A series of variant cases addresses uncertainties in the inference of parameters and the boundary conditions. The study uses HYDRASTAR, the SKB stochastic continuum groundwater modelling program, to compute the heads, Darcy velocities at each representative canister position and the advective travel times and paths through the geosphere. The nested modelling approach and the scale dependency of hydraulic conductivity raise a number of questions regarding the regional to site-scale mass balance and the method's self-consistency. The transfer of regional heads via constant head boundaries preserves the regional pattern recharge and discharge in the site-scale model, and the regional to site-scale mass balance is thought to be adequate. The upscaling method appears to be approximately self-consistent with respect to the median performance measures at various grid scales. A series of variant cases indicates that the study results are insensitive to alternative methods on transferring boundary conditions from the regional model to the site-scale model. The flow paths, travel times and simulated heads appear to be consistent with on-site observations and simple scoping calculations. The variabilities of the performance measures are quite high for the Base Case, but the

  16. Large scale hydro-economic modelling for policy support

    Science.gov (United States)

    de Roo, Ad; Burek, Peter; Bouraoui, Faycal; Reynaud, Arnaud; Udias, Angel; Pistocchi, Alberto; Lanzanova, Denis; Trichakis, Ioannis; Beck, Hylke; Bernhard, Jeroen

    2014-05-01

    To support European Union water policy making and policy monitoring, a hydro-economic modelling environment has been developed to assess optimum combinations of water retention measures, water savings measures, and nutrient reduction measures for continental Europe. This modelling environment consists of linking the agricultural CAPRI model, the LUMP land use model, the LISFLOOD water quantity model, the EPIC water quality model, the LISQUAL combined water quantity, quality and hydro-economic model, and a multi-criteria optimisation routine. With this modelling environment, river basin scale simulations are carried out to assess the effects of water-retention measures, water-saving measures, and nutrient-reduction measures on several hydro-chemical indicators, such as the Water Exploitation Index (WEI), Nitrate and Phosphate concentrations in rivers, the 50-year return period river discharge as an indicator for flooding, and economic losses due to water scarcity for the agricultural sector, the manufacturing-industry sector, the energy-production sector and the domestic sector, as well as the economic loss due to flood damage. Recently, this model environment is being extended with a groundwater model to evaluate the effects of measures on the average groundwater table and available resources. Also, water allocation rules are addressed, while having environmental flow included as a minimum requirement for the environment. Economic functions are currently being updated as well. Recent development and examples will be shown and discussed, as well as open challenges.

  17. Modeling and simulation in tribology across scales: An overview

    DEFF Research Database (Denmark)

    Vakis, A.I.; Yastrebov, V.A.; Scheibert, J.

    2018-01-01

    This review summarizes recent advances in the area of tribology based on the outcome of a Lorentz Center workshop surveying various physical, chemical and mechanical phenomena across scales. Among the main themes discussed were those of rough surface representations, the breakdown of continuum...... nonlinear effects of plasticity, adhesion, friction, wear, lubrication and surface chemistry in tribological models. For each topic, we propose some research directions....

  18. Phenomenological aspects of no-scale inflation models

    Energy Technology Data Exchange (ETDEWEB)

    Ellis, John [Theoretical Particle Physics and Cosmology Group, Department of Physics, King' s College London, WC2R 2LS London (United Kingdom); Garcia, Marcos A.G.; Olive, Keith A. [William I. Fine Theoretical Physics Institute, School of Physics and Astronomy, University of Minnesota, 116 Church Street SE, Minneapolis, MN 55455 (United States); Nanopoulos, Dimitri V., E-mail: john.ellis@cern.ch, E-mail: garciagarcia@physics.umn.edu, E-mail: dimitri@physics.tamu.edu, E-mail: olive@physics.umn.edu [George P. and Cynthia W. Mitchell Institute for Fundamental Physics and Astronomy, Texas A and M University, College Station, 77843 Texas (United States)

    2015-10-01

    We discuss phenomenological aspects of inflationary models wiith a no-scale supergravity Kähler potential motivated by compactified string models, in which the inflaton may be identified either as a Kähler modulus or an untwisted matter field, focusing on models that make predictions for the scalar spectral index n{sub s} and the tensor-to-scalar ratio r that are similar to the Starobinsky model. We discuss possible patterns of soft supersymmetry breaking, exhibiting examples of the pure no-scale type m{sub 0} = B{sub 0} = A{sub 0} = 0, of the CMSSM type with universal A{sub 0} and m{sub 0} ≠ 0 at a high scale, and of the mSUGRA type with A{sub 0} = B{sub 0} + m{sub 0} boundary conditions at the high input scale. These may be combined with a non-trivial gauge kinetic function that generates gaugino masses m{sub 1/2} ≠ 0, or one may have a pure gravity mediation scenario where trilinear terms and gaugino masses are generated through anomalies. We also discuss inflaton decays and reheating, showing possible decay channels for the inflaton when it is either an untwisted matter field or a Kähler modulus. Reheating is very efficient if a matter field inflaton is directly coupled to MSSM fields, and both candidates lead to sufficient reheating in the presence of a non-trivial gauge kinetic function.

  19. Perturbation theory instead of large scale shell model calculations

    International Nuclear Information System (INIS)

    Feldmeier, H.; Mankos, P.

    1977-01-01

    Results of large scale shell model calculations for (sd)-shell nuclei are compared with a perturbation theory provides an excellent approximation when the SU(3)-basis is used as a starting point. The results indicate that perturbation theory treatment in an SU(3)-basis including 2hω excitations should be preferable to a full diagonalization within the (sd)-shell. (orig.) [de

  20. Next-generation genome-scale models for metabolic engineering

    DEFF Research Database (Denmark)

    King, Zachary A.; Lloyd, Colton J.; Feist, Adam M.

    2015-01-01

    Constraint-based reconstruction and analysis (COBRA) methods have become widely used tools for metabolic engineering in both academic and industrial laboratories. By employing a genome-scale in silico representation of the metabolic network of a host organism, COBRA methods can be used to predict...... examples of applying COBRA methods to strain optimization are presented and discussed. Then, an outlook is provided on the next generation of COBRA models and the new types of predictions they will enable for systems metabolic engineering....