Rethinking Partnerships on a Decentralized Campus

ERIC Educational Resources Information Center

Dufault, Katie H.

2017-01-01

Decentralization is an effective approach for structuring campus learning and success centers. McShane & Von Glinow (2007) describe decentralization as "an organizational model where decision authority and power are dispersed among units rather than held by a single small group of administrators" (p. 237). A decentralized structure…

Preference of methadone maintenance patients for the integrative and decentralized service delivery models in Vietnam.

PubMed

Tran, Bach Xuan; Nguyen, Long Hoang; Phan, Huong Thu Thi; Nguyen, Linh Khanh; Latkin, Carl A

2015-09-17

Integrating and decentralizing services are essential to increase the accessibility and provide comprehensive care for methadone patients. Moreover, they assure the sustainability of a HIV/AIDS prevention program by reducing the implementation cost. This study aimed to measure the preference of patients enrolling in a MMT program for integrated and decentralized MMT clinics and then further examine related factors. A cross-sectional study was conducted among 510 patients receiving methadone at 3 clinics in Hanoi. Structured questionnaires were used to collect data about the preference for integrated and decentralized MMT services. Covariates including socio-economic status; health-related quality of life (using EQ-5D-5 L instrument) and HIV status; history of drug use along with MMT treatment; and exposure to the discrimination within family and community were also investigated. Multivariate logistic regression with polynomial fractions was used to identify the determinants of preference for integrative and decentralized models. Of 510 patients enrolled, 66.7 and 60.8 % preferred integrated and decentralized models, respectively. The main reason for preferring the integrative model was the convenience of use of various services (53.2 %), while more privacy (43.5 %) was the primary reason to select stand-alone model. People preferred the decentralized model primarily because of travel cost reduction (95.0 %), while the main reason for not selecting the model was increased privacy (7.7 %). After adjusting for covariates, factors influencing the preference for integrative model were poor socioeconomic status, anxiety/depression, history of drug rehabilitation, and ever disclosed health status; while exposure to community discrimination inversely associated with this preference. In addition, people who were self-employed, had a longer duration of MMT, and use current MMT with comprehensive HIV services were less likely to select decentralized model. In conclusion, the study confirmed the high preference of MMT patients for the integrative and decentralized MMT service delivery models. The convenience of healthcare services utilization and reduction of geographical barriers were the main reasons to use those models within drug use populations in Vietnam. Countering community stigma and encouraging communication between patients and their societies needed to be considered when implementing those models.

From social network (centralized vs. decentralized) to collective decision-making (unshared vs. shared consensus).

PubMed

Sueur, Cédric; Deneubourg, Jean-Louis; Petit, Odile

2012-01-01

Relationships we have with our friends, family, or colleagues influence our personal decisions, as well as decisions we make together with others. As in human beings, despotism and egalitarian societies seem to also exist in animals. While studies have shown that social networks constrain many phenomena from amoebae to primates, we still do not know how consensus emerges from the properties of social networks in many biological systems. We created artificial social networks that represent the continuum from centralized to decentralized organization and used an agent-based model to make predictions about the patterns of consensus and collective movements we observed according to the social network. These theoretical results showed that different social networks and especially contrasted ones--star network vs. equal network--led to totally different patterns. Our model showed that, by moving from a centralized network to a decentralized one, the central individual seemed to lose its leadership in the collective movement's decisions. We, therefore, showed a link between the type of social network and the resulting consensus. By comparing our theoretical data with data on five groups of primates, we confirmed that this relationship between social network and consensus also appears to exist in animal societies.

Federated learning of predictive models from federated Electronic Health Records.

PubMed

Brisimi, Theodora S; Chen, Ruidi; Mela, Theofanie; Olshevsky, Alex; Paschalidis, Ioannis Ch; Shi, Wei

2018-04-01

In an era of "big data," computationally efficient and privacy-aware solutions for large-scale machine learning problems become crucial, especially in the healthcare domain, where large amounts of data are stored in different locations and owned by different entities. Past research has been focused on centralized algorithms, which assume the existence of a central data repository (database) which stores and can process the data from all participants. Such an architecture, however, can be impractical when data are not centrally located, it does not scale well to very large datasets, and introduces single-point of failure risks which could compromise the integrity and privacy of the data. Given scores of data widely spread across hospitals/individuals, a decentralized computationally scalable methodology is very much in need. We aim at solving a binary supervised classification problem to predict hospitalizations for cardiac events using a distributed algorithm. We seek to develop a general decentralized optimization framework enabling multiple data holders to collaborate and converge to a common predictive model, without explicitly exchanging raw data. We focus on the soft-margin l 1 -regularized sparse Support Vector Machine (sSVM) classifier. We develop an iterative cluster Primal Dual Splitting (cPDS) algorithm for solving the large-scale sSVM problem in a decentralized fashion. Such a distributed learning scheme is relevant for multi-institutional collaborations or peer-to-peer applications, allowing the data holders to collaborate, while keeping every participant's data private. We test cPDS on the problem of predicting hospitalizations due to heart diseases within a calendar year based on information in the patients Electronic Health Records prior to that year. cPDS converges faster than centralized methods at the cost of some communication between agents. It also converges faster and with less communication overhead compared to an alternative distributed algorithm. In both cases, it achieves similar prediction accuracy measured by the Area Under the Receiver Operating Characteristic Curve (AUC) of the classifier. We extract important features discovered by the algorithm that are predictive of future hospitalizations, thus providing a way to interpret the classification results and inform prevention efforts. Copyright © 2018 Elsevier B.V. All rights reserved.

Decentralizing the "Future Planning" of Public Education. Project SIMU School: Santa Clara County Component.

ERIC Educational Resources Information Center

Candoli, I. C.; Leu, Donald J.

This analysis draws on a variety of experiences with and models of centralized and decentralized school systems now in existence. The decentralized model or profile posed for consideration is intended as a basis for the development of a process by which indigenous models can be established for any locale as unique local variables are identified…

Lessons learned from a pharmacy practice model change at an academic medical center.

PubMed

Knoer, Scott J; Pastor, John D; Phelps, Pamela K

2010-11-01

The development and implementation of a new pharmacy practice model at an academic medical center are described. Before the model change, decentralized pharmacists responsible for order entry and verification and clinical specialists were both present on the care units. Staff pharmacists were responsible for medication distribution and sterile product preparation. The decentralized pharmacists handling orders were not able to use their clinical training, the practice model was inefficient, and few clinical services were available during evenings and weekends. A task force representing all pharmacy department roles developed a process and guiding principles for the model change, collected data, and decided on a model. Teams consisting of decentralized pharmacists, decentralized pharmacy technicians, and team leaders now work together to meet patients' pharmacy needs and further departmental safety, quality, and cost-saving goals. Decentralized service hours have been expanded through operational efficiencies, including use of automation (e.g., computerized provider order entry, wireless computers on wheels used during rounds with physician teams). Nine clinical specialist positions were replaced by five team leader positions and four pharmacists functioning in decentralized roles. Additional staff pharmacist positions were shifted into decentralized roles, and the hospital was divided into areas served by teams including five to eight pharmacists. Technicians are directly responsible for medication distribution. No individual's job was eliminated. The new practice model allowed better alignment of staff with departmental goals, expanded pharmacy hours and services, more efficient medication distribution, improved employee engagement, and a staff succession plan.

Cooperative Search by UAV Teams: A Model Predictive Approach Using Dynamic Graphs

DTIC Science & Technology

2011-10-01

decentralized processing and control architecture. SLAMEM asset models accurately represent the Unicorn UAV platforms and other standard military platforms in...IMPLEMENTATION The CGBMPS algorithm has been successfully field-tested using both Unicorn [27] and Raven [20] UAV platforms. This section describes...the hardware-software system setup and implementation used for testing with Unicorns , Toyon’s UAV test platform. We also present some results from the

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

PubMed

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.

Integration of decentralized torrefaction with centralized catalytic pyrolysis to produce green aromatics from coffee grounds.

PubMed

Chai, Li; Saffron, Christopher M; Yang, Yi; Zhang, Zhongyu; Munro, Robert W; Kriegel, Robert M

2016-02-01

The aim of this work was to integrate decentralized torrefaction with centralized catalytic pyrolysis to convert coffee grounds into the green aromatic precursors of terephthalic acid, namely benzene, toluene, ethylbenzene, and xylenes (BTEX). An economic analysis of this bioproduct system was conducted to examine BTEX yields, biomass costs and their sensitivities. Model predictions were verified experimentally using pyrolysis GC/MS to quantify BTEX yields for raw and torrefied biomass. The production cost was minimized when the torrefier temperature and residence time were 239°C and 34min, respectively. This optimization study found conditions that justify torrefaction as a pretreatment for making BTEX, provided that starting feedstock costs are below $58 per tonne. Copyright © 2015. Published by Elsevier Ltd.

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

PubMed

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.

Algorithms for output feedback, multiple-model, and decentralized control problems

NASA Technical Reports Server (NTRS)

Halyo, N.; Broussard, J. R.

1984-01-01

The optimal stochastic output feedback, multiple-model, and decentralized control problems with dynamic compensation are formulated and discussed. Algorithms for each problem are presented, and their relationship to a basic output feedback algorithm is discussed. An aircraft control design problem is posed as a combined decentralized, multiple-model, output feedback problem. A control design is obtained using the combined algorithm. An analysis of the design is presented.

Decentralized Bayesian search using approximate dynamic programming methods.

PubMed

Zhao, Yijia; Patek, Stephen D; Beling, Peter A

2008-08-01

We consider decentralized Bayesian search problems that involve a team of multiple autonomous agents searching for targets on a network of search points operating under the following constraints: 1) interagent communication is limited; 2) the agents do not have the opportunity to agree in advance on how to resolve equivalent but incompatible strategies; and 3) each agent lacks the ability to control or predict with certainty the actions of the other agents. We formulate the multiagent search-path-planning problem as a decentralized optimal control problem and introduce approximate dynamic heuristics that can be implemented in a decentralized fashion. After establishing some analytical properties of the heuristics, we present computational results for a search problem involving two agents on a 5 x 5 grid.

Tilt and decentration of intraocular lenses in vivo from Purkinje and Scheimpflug imaging. Validation study.

PubMed

de Castro, Alberto; Rosales, Patricia; Marcos, Susana

2007-03-01

To measure tilt and decentration of intraocular lenses (IOLs) with Scheimpflug and Purkinje imaging systems in physical model eyes with known amounts of tilt and decentration and patients. Instituto de Optica Daza de Valdés, Consejo Superior de Investigaciones Científicas, Madrid, Spain. Measurements of IOL tilt and decentration were obtained using a commercial Scheimpflug system (Pentacam, Oculus), custom algorithms, and a custom-built Purkinje imaging apparatus. Twenty-five Scheimpflug images of the anterior segment of the eye were obtained at different meridians. Custom algorithms were used to process the images (correction of geometrical distortion, edge detection, and curve fittings). Intraocular lens tilt and decentration were estimated by fitting sinusoidal functions to the projections of the pupillary axis and IOL axis in each image. The Purkinje imaging system captures pupil images showing reflections of light from the anterior corneal surface and anterior and posterior lens surfaces. Custom algorithms were used to detect the Purkinje image locations and estimate IOL tilt and decentration based on a linear system equation and computer eye models with individual biometry. Both methods were validated with a physical model eye in which IOL tilt and decentration can be set nominally. Twenty-one eyes of 12 patients with IOLs were measured with both systems. Measurements of the physical model eye showed an absolute discrepancy between nominal and measured values of 0.279 degree (Purkinje) and 0.243 degree (Scheimpflug) for tilt and 0.094 mm (Purkinje) and 0.228 mm (Scheimpflug) for decentration. In patients, the mean tilt was less than 2.6 degrees and the mean decentration less than 0.4 mm. Both techniques showed mirror symmetry between right eyes and left eyes for tilt around the vertical axis and for decentration in the horizontal axis. Both systems showed high reproducibility. Validation experiments on physical model eyes showed slightly higher accuracy with the Purkinje method than the Scheimpflug imaging method. Horizontal measurements of patients with both techniques were highly correlated. The IOLs tended to be tilted and decentered nasally in most patients.

Fully decentralized estimation and control for a modular wheeled mobile robot

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mutambara, A.G.O.; Durrant-Whyte, H.F.

2000-06-01

In this paper, the problem of fully decentralized data fusion and control for a modular wheeled mobile robot (WMR) is addressed. This is a vehicle system with nonlinear kinematics, distributed multiple sensors, and nonlinear sensor models. The problem is solved by applying fully decentralized estimation and control algorithms based on the extended information filter. This is achieved by deriving a modular, decentralized kinematic model by using plane motion kinematics to obtain the forward and inverse kinematics for a generalized simple wheeled vehicle. This model is then used in the decentralized estimation and control algorithms. WMR estimation and control is thusmore » obtained locally using reduced order models with reduced communication of information between nodes is carried out after every measurement (full rate communication), the estimates and control signals obtained at each node are equivalent to those obtained by a corresponding centralized system. Transputer architecture is used as the basis for hardware and software design as it supports the extensive communication and concurrency requirements that characterize modular and decentralized systems. The advantages of a modular WMR vehicle include scalability, application flexibility, low prototyping costs, and high reliability.« less

COINSTAC: Decentralizing the future of brain imaging analysis

PubMed Central

Ming, Jing; Verner, Eric; Sarwate, Anand; Kelly, Ross; Reed, Cory; Kahleck, Torran; Silva, Rogers; Panta, Sandeep; Turner, Jessica; Plis, Sergey; Calhoun, Vince

2017-01-01

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. PMID:29123643

From Social Network (Centralized vs. Decentralized) to Collective Decision-Making (Unshared vs. Shared Consensus)

PubMed Central

Sueur, Cédric; Deneubourg, Jean-Louis; Petit, Odile

2012-01-01

Relationships we have with our friends, family, or colleagues influence our personal decisions, as well as decisions we make together with others. As in human beings, despotism and egalitarian societies seem to also exist in animals. While studies have shown that social networks constrain many phenomena from amoebae to primates, we still do not know how consensus emerges from the properties of social networks in many biological systems. We created artificial social networks that represent the continuum from centralized to decentralized organization and used an agent-based model to make predictions about the patterns of consensus and collective movements we observed according to the social network. These theoretical results showed that different social networks and especially contrasted ones – star network vs. equal network - led to totally different patterns. Our model showed that, by moving from a centralized network to a decentralized one, the central individual seemed to lose its leadership in the collective movement's decisions. We, therefore, showed a link between the type of social network and the resulting consensus. By comparing our theoretical data with data on five groups of primates, we confirmed that this relationship between social network and consensus also appears to exist in animal societies. PMID:22393416

Modeling a multivariable reactor and on-line model predictive control.

PubMed

Yu, D W; Yu, D L

2005-10-01

A nonlinear first principle model is developed for a laboratory-scaled multivariable chemical reactor rig in this paper and the on-line model predictive control (MPC) is implemented to the rig. The reactor has three variables-temperature, pH, and dissolved oxygen with nonlinear dynamics-and is therefore used as a pilot system for the biochemical industry. A nonlinear discrete-time model is derived for each of the three output variables and their model parameters are estimated from the real data using an adaptive optimization method. The developed model is used in a nonlinear MPC scheme. An accurate multistep-ahead prediction is obtained for MPC, where the extended Kalman filter is used to estimate system unknown states. The on-line control is implemented and a satisfactory tracking performance is achieved. The MPC is compared with three decentralized PID controllers and the advantage of the nonlinear MPC over the PID is clearly shown.

Reduced modeling of flexible structures for decentralized control

NASA Technical Reports Server (NTRS)

Yousuff, A.; Tan, T. M.; Bahar, L. Y.; Konstantinidis, M. F.

1986-01-01

Based upon the modified finite element-transfer matrix method, this paper presents a technique for reduced modeling of flexible structures for decentralized control. The modeling decisions are carried out at (finite-) element level, and are dictated by control objectives. A simply supported beam with two sets of actuators and sensors (linear force actuator and linear position and velocity sensors) is considered for illustration. In this case, it is conjectured that the decentrally controlled closed loop system is guaranteed to be at least marginally stable.

Decentralized control of Markovian decision processes: Existence Sigma-admissable policies

NASA Technical Reports Server (NTRS)

Greenland, A.

1980-01-01

The problem of formulating and analyzing Markov decision models having decentralized information and decision patterns is examined. Included are basic examples as well as the mathematical preliminaries needed to understand Markov decision models and, further, to superimpose decentralized decision structures on them. The notion of a variance admissible policy for the model is introduced and it is proved that there exist (possibly nondeterministic) optional policies from the class of variance admissible policies. Directions for further research are explored.

Decentralized Decision Making Toward Educational Goals.

ERIC Educational Resources Information Center

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…

Decentralized control of sound radiation using iterative loop recovery.

PubMed

Schiller, Noah H; Cabell, Randolph H; Fuller, Chris R

2010-10-01

A decentralized model-based control strategy is designed to reduce low-frequency sound radiation from periodically stiffened panels. While decentralized control systems tend to be scalable, performance can be limited due to modeling error introduced by the unmodeled interaction between neighboring control units. Since bounds on modeling error are not known in advance, it is difficult to ensure the decentralized control system will be robust without making the controller overly conservative. Therefore an iterative approach is suggested, which utilizes frequency-shaped loop recovery. The approach accounts for modeling error introduced by neighboring control loops, requires no communication between subsystems, and is relatively simple. The control strategy is evaluated numerically using a model of a stiffened aluminum panel that is representative of the sidewall of an aircraft. Simulations demonstrate that the iterative approach can achieve significant reductions in radiated sound power from the stiffened panel without destabilizing neighboring control units.

Decentralized Control of Sound Radiation Using Iterative Loop Recovery

NASA Technical Reports Server (NTRS)

Schiller, Noah H.; Cabell, Randolph H.; Fuller, Chris R.

2009-01-01

A decentralized model-based control strategy is designed to reduce low-frequency sound radiation from periodically stiffened panels. While decentralized control systems tend to be scalable, performance can be limited due to modeling error introduced by the unmodeled interaction between neighboring control units. Since bounds on modeling error are not known in advance, it is difficult to ensure the decentralized control system will be robust without making the controller overly conservative. Therefore an iterative approach is suggested, which utilizes frequency-shaped loop recovery. The approach accounts for modeling error introduced by neighboring control loops, requires no communication between subsystems, and is relatively simple. The control strategy is evaluated numerically using a model of a stiffened aluminum panel that is representative of the sidewall of an aircraft. Simulations demonstrate that the iterative approach can achieve significant reductions in radiated sound power from the stiffened panel without destabilizing neighboring control units.

Intraoperative centration during small incision lenticule extraction (SMILE)

PubMed Central

Wong, John X.; Wong, Elizabeth P.; Htoon, Hla M.; Mehta, Jodhbir S.

2017-01-01

Abstract To evaluate intraoperative decentration from pupil center and kappa intercept during small incision lenticule extraction (SMILE) and its impact on visual outcomes. This was a retrospective noncomparative case series. A total of 164 eyes that underwent SMILE at the Singapore National Eye Center were included. Screen captures of intraoperative videos were analyzed. Preoperative and 3 month postoperative vision and refractive data were analyzed against decentration. The mean preoperative spherical equivalent (SE) was −5.84 ± 1.77. The mean decentration from the pupil center and from kappa intercept were 0.13 ± 0.06 mm and 0.47mm ± 0.25 mm, respectively. For efficacy and predictability, 69.6% and 95.0% of eyes achieved a visual acuity (VA) of 20/20 and 20/30, respectively, while 83.8% and 97.2% of eyes were within ±0.5D and ±1.0D of the targeted SE. When analyzed across 3 groups of decentration from the pupil center (<0.1 mm, 0.1–0.2 mm, and >0.2 mm), there was no statistically significant association between decentration, safety, efficacy, and predictability. When analyzed across 4 groups of decentration from kappa intercept (<0.2 mm, 0.2–<0.4 mm, 0.4–<0.6 mm, and ≥0.6 mm), there was a trend toward higher efficacy for eyes with decentration of kappa intercept between 0.4 and <0.6 mm (P = .097). A total of 85.4% of eyes in the 0.4 to <0.6 mm group had unaided distance VA of 20/20 or better, as compared to only 57.8% of eyes in ≥0.6 mm group. Decentration of 0.13 mm from the pupil center does not result in compromised visual outcomes. Decentration of greater than 0.6 mm from the kappa intercept may result in compromised visual outcomes. There was a trend toward better efficacy in eyes which had decentered treatment from 0.4 to <0.6 mm from the kappa intercept. Patients with a large kappa intercept (>0.6 mm) should have their lenticule created 0.4 to 0.6 mm from the kappa intercept and not close to the pupil. PMID:28422822

Centralization vs. Decentralization: A Location Analysis Approach for Librarians

ERIC Educational Resources Information Center

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)

Some aspects of control of a large-scale dynamic system

NASA Technical Reports Server (NTRS)

Aoki, M.

1975-01-01

Techniques of predicting and/or controlling the dynamic behavior of large scale systems are discussed in terms of decentralized decision making. Topics discussed include: (1) control of large scale systems by dynamic team with delayed information sharing; (2) dynamic resource allocation problems by a team (hierarchical structure with a coordinator); and (3) some problems related to the construction of a model of reduced dimension.

Visualizing the Collective Learner through Decentralized Networks

ERIC Educational Resources Information Center

Castro, Juan Carlos

2015-01-01

Understandings of decentralized networks are increasingly used to describe a way to structure curriculum and pedagogy. It is often understood as a structural model to organize pedagogical and curricular relationships in which there is no center. While this is important it also bears introducing into the discourse that decentralized networks are…

Two controller design approaches for decentralized systems

NASA Technical Reports Server (NTRS)

Ozguner, U.; Khorrami, F.; Iftar, A.

1988-01-01

Two different philosophies for designing the controllers of decentralized systems are considered within a quadratic regulator framework which is generalized to admit decentralized frequency weighting. In the first approach, the total system model is examined, and the feedback strategy for each channel or subsystem is determined. In the second approach, separate, possibly overlapping, and uncoupled models are analyzed for each channel, and the results can be combined to study the original system. The two methods are applied to the example of a model of the NASA COFS Mast Flight System.

A network approach to decentralized coordination of energy production-consumption grids.

PubMed

Omodei, Elisa; Arenas, Alex

2018-01-01

Energy grids are facing a relatively new paradigm consisting in the formation of local distributed energy sources and loads that can operate in parallel independently from the main power grid (usually called microgrids). One of the main challenges in microgrid-like networks management is that of self-adapting to the production and demands in a decentralized coordinated way. Here, we propose a stylized model that allows to analytically predict the coordination of the elements in the network, depending on the network topology. Surprisingly, almost global coordination is attained when users interact locally, with a small neighborhood, instead of the obvious but more costly all-to-all coordination. We compute analytically the optimal value of coordinated users in random homogeneous networks. The methodology proposed opens a new way of confronting the analysis of energy demand-side management in networked systems.

The Effect of Fiscal Decentralization on Under-five Mortality in Iran: A Panel Data Analysis.

PubMed

Samadi, Ali Hussein; Keshtkaran, Ali; Kavosi, Zahra; Vahedi, Sajad

2013-11-01

Fiscal Decentralization (FD) in many cases is encouraged as a strong means of improving the efficiency and equity in the provision of public goods, such as healthcare services. This issue has urged the researchers to experimentally examine the relationship between fiscal decentralization indicators and health outcomes. In this study we examine the effect of Fiscal Decentralization in Medical Universities (FDMU) and Fiscal Decentralization in Provincial Revenues (FDPR) on Under-Five Mortality Rate (U5M) in provinces of Iran over the period between 2007 and 2010. We employed panel data methods in this article. The results of the Pesaran CD test demonstrated that most of the variables used in the analysis were cross-sectionally dependent. The Hausman test results suggested that fixed-effects were more appropriate to estimate our model. We estimated the fixed-effect model by using Driscoll-Kraay standard errors as a remedy for cross-sectional dependency. According to the findings of this research, fiscal decentralization in the health sector had a negative impact on U5M. On the other hand, fiscal decentralization in provincial revenues had a positive impact on U5M. In addition, U5M had a negative association with the density of physicians, hospital beds, and provincial GDP per capita, but a positive relationship with Gini coefficient and unemployment. The findings of our study indicated that fiscal decentralization should be emphasized in the health sector. The results suggest the need for caution in the implementation of fiscal decentralization in provincial revenues.

Beyond the Diversity Crisis Model: Decentralized Diversity Planning and Implementation

ERIC Educational Resources Information Center

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…

Decentralized Adaptive Control of Systems with Uncertain Interconnections, Plant-Model Mismatch and Actuator Failures

NASA Technical Reports Server (NTRS)

Patre, Parag; Joshi, Suresh M.

2011-01-01

Decentralized adaptive control is considered for systems consisting of multiple interconnected subsystems. It is assumed that each subsystem s parameters are uncertain and the interconnection parameters are not known. In addition, mismatch can exist between each subsystem and its reference model. A strictly decentralized adaptive control scheme is developed, wherein each subsystem has access only to its own state but has the knowledge of all reference model states. The mismatch is estimated online for each subsystem and the mismatch estimates are used to adaptively modify the corresponding reference models. The adaptive control scheme is extended to the case with actuator failures in addition to mismatch.

Predicting crystalline lens fall caused by accommodation from changes in wavefront error

PubMed Central

He, Lin; Applegate, Raymond A.

2011-01-01

PURPOSE To illustrate and develop a method for estimating crystalline lens decentration as a function of accommodative response using changes in wavefront error and show the method and limitations using previously published data (2004) from 2 iridectomized monkey eyes so that clinicians understand how spherical aberration can induce coma, in particular in intraocular lens surgery. SETTINGS College of Optometry, University of Houston, Houston, USA. DESIGN Evaluation of diagnostic test or technology. METHODS Lens decentration was estimated by displacing downward the wavefront error of the lens with respect to the limiting aperture (7.0 mm) and ocular first surface wavefront error for each accommodative response (0.00 to 11.00 diopters) until measured values of vertical coma matched previously published experimental data (2007). Lens decentration was also calculated using an approximation formula that only included spherical aberration and vertical coma. RESULTS The change in calculated vertical coma was consistent with downward lens decentration. Calculated downward lens decentration peaked at approximately 0.48 mm of vertical decentration in the right eye and approximately 0.31 mm of decentration in the left eye using all Zernike modes through the 7th radial order. Calculated lens decentration using only coma and spherical aberration formulas was peaked at approximately 0.45 mm in the right eye and approximately 0.23 mm in the left eye. CONCLUSIONS Lens fall as a function of accommodation was quantified noninvasively using changes in vertical coma driven principally by the accommodation-induced changes in spherical aberration. The newly developed method was valid for a large pupil only. PMID:21700108

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

PubMed Central

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

Integrating Collaborative and Decentralized Models to Support Ubiquitous Learning

ERIC Educational Resources Information Center

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…

Market-oriented Programming Using Small-world Networks for Controlling Building Environments

NASA Astrophysics Data System (ADS)

Shigei, Noritaka; Miyajima, Hiromi; Osako, Tsukasa

The market model, which is one of the economic activity models, is modeled as an agent system, and applying the model to the resource allocation problem has been studied. For air conditioning control of building, which is one of the resource allocation problems, an effective method based on the agent system using auction has been proposed for traditional PID controller. On the other hand, it has been considered that this method is performed by decentralized control. However, its decentralization is not perfect, and its performace is not enough. In this paper, firstly, we propose a perfectly decentralized agent model and show its performance. Secondly, in order to improve the model, we propose the agent model based on small-world model. The effectiveness of the proposed model is shown by simulation.

Comparison of satisfaction with care between two different models of HIV care delivery in St. Petersburg, Russia.

PubMed

Suvorova, Alena; Belyakov, Andrey; Makhamatova, Aliia; Ustinov, Andrey; Levina, Olga; Tulupyev, Alexander; Niccolai, Linda; Rassokhin, Vadim; Heimer, Robert

2015-01-01

Prior to 2010, medical care for people living with HIV/AIDS was provided at an outpatient facility near the center of St. Petersburg. Since then, HIV specialty clinics have been established in more outlying regions of the city. The study examined the effect of this decentralization of HIV care on patients' satisfaction with care in clinics of St. Petersburg, Russia. We conducted a cross-sectional study with 418 HIV-positive patients receiving care at the St. Petersburg AIDS Center or at District Infectious Disease Departments (centralized and decentralized models, respectively). Face-to-face interviews included questions about psychosocial characteristics, patient's satisfaction with care, and clinic-related patient experience. Abstraction of medical records provided information on patients' viral load. To compare centralized and decentralized models of care delivery, we performed bivariate and multivariate analysis. Clients of District Infectious Disease Departments spent less time in lines and traveling to reach the clinic, and they had stronger relationships with their doctor. The overall satisfaction with care was high, with 86% of the sample reporting high level of satisfaction. Nevertheless, satisfaction with care was strongly and positively associated with the decentralized model of care and Patient-Doctor Relationship Score. Patient experience elements such as waiting time, travel time, and number of services used were not significant factors related to satisfaction. Given the positive association of satisfaction with decentralized service delivery, it is worth exploring decentralization as one way of improving healthcare services for people living with HIV/AIDS.

On decentralized design: Rationale, dynamics, and effects on decision-making

NASA Astrophysics Data System (ADS)

Chanron, Vincent

The focus of this dissertation is the design of complex systems, including engineering systems such as cars, airplanes, and satellites. Companies who design these systems are under constant pressure to design better products that meet customer expectations, and competition forces them to develop them faster. One of the responses of the industry to these conflicting challenges has been the decentralization of the design responsibilities. The current lack of understanding of the dynamics of decentralized design processes is the main motivation for this research, and places value on the descriptive base. It identifies the main reasons and the true benefits for companies to decentralize the design of their products. It also demonstrates the limitations of this approach by listing the relevant issues and problems created by the decentralization of decisions. Based on these observations, a game-theoretic approach to decentralized design is proposed to model the decisions made during the design process. The dynamics are modeled using mathematical formulations inspired from control theory. Building upon this formalism, the issue of convergence in decentralized design is analyzed: the equilibrium points of the design space are identified and convergent and divergent patterns are recognized. This rigorous investigation of the design process provides motivation and support for proposing new approaches to decentralized design problems. Two methods are developed, which aim at improving the design process in two ways: decreasing the product development time, and increasing the optimality of the final design. The frame of these methods are inspired by eigenstructure decomposition and set-based design, respectively. The value of the research detailed within this dissertation is in the proposed methods which are built upon the sound mathematical formalism developed. The contribution of this work is two fold: rigorous investigation of the design process, and practical support to decision-making in decentralized environments.

A three-level atomicity model for decentralized workflow management systems

NASA Astrophysics Data System (ADS)

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.

Polya's bees: A model of decentralized decision-making.

PubMed

Golman, Russell; Hagmann, David; Miller, John H

2015-09-01

How do social systems make decisions with no single individual in control? We observe that a variety of natural systems, including colonies of ants and bees and perhaps even neurons in the human brain, make decentralized decisions using common processes involving information search with positive feedback and consensus choice through quorum sensing. We model this process with an urn scheme that runs until hitting a threshold, and we characterize an inherent tradeoff between the speed and the accuracy of a decision. The proposed common mechanism provides a robust and effective means by which a decentralized system can navigate the speed-accuracy tradeoff and make reasonably good, quick decisions in a variety of environments. Additionally, consensus choice exhibits systemic risk aversion even while individuals are idiosyncratically risk-neutral. This too is adaptive. The model illustrates how natural systems make decentralized decisions, illuminating a mechanism that engineers of social and artificial systems could imitate.

Polya’s bees: A model of decentralized decision-making

PubMed Central

Golman, Russell; Hagmann, David; Miller, John H.

2015-01-01

How do social systems make decisions with no single individual in control? We observe that a variety of natural systems, including colonies of ants and bees and perhaps even neurons in the human brain, make decentralized decisions using common processes involving information search with positive feedback and consensus choice through quorum sensing. We model this process with an urn scheme that runs until hitting a threshold, and we characterize an inherent tradeoff between the speed and the accuracy of a decision. The proposed common mechanism provides a robust and effective means by which a decentralized system can navigate the speed-accuracy tradeoff and make reasonably good, quick decisions in a variety of environments. Additionally, consensus choice exhibits systemic risk aversion even while individuals are idiosyncratically risk-neutral. This too is adaptive. The model illustrates how natural systems make decentralized decisions, illuminating a mechanism that engineers of social and artificial systems could imitate. PMID:26601255

A network approach to decentralized coordination of energy production-consumption grids

PubMed Central

Arenas, Alex

2018-01-01

Energy grids are facing a relatively new paradigm consisting in the formation of local distributed energy sources and loads that can operate in parallel independently from the main power grid (usually called microgrids). One of the main challenges in microgrid-like networks management is that of self-adapting to the production and demands in a decentralized coordinated way. Here, we propose a stylized model that allows to analytically predict the coordination of the elements in the network, depending on the network topology. Surprisingly, almost global coordination is attained when users interact locally, with a small neighborhood, instead of the obvious but more costly all-to-all coordination. We compute analytically the optimal value of coordinated users in random homogeneous networks. The methodology proposed opens a new way of confronting the analysis of energy demand-side management in networked systems. PMID:29364962

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".

PubMed

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.

Multi-Agent Task Negotiation Among UAVs to Defend Against Swarm Attacks

DTIC Science & Technology

2012-03-01

are based on economic models [39]. Auction methods of task coordination also attempt to deal with agents dealing with noisy, dynamic environments...August 2006. [34] M. Alighanbari, “ Robust and decentralized task assignment algorithms for uavs,” Ph.D. dissertation, Massachusetts Institute of Technology...Implicit Coordination . . . . . . . . . . . . . 12 2.4 Decentralized Algorithm B - Market- Based . . . . . . . . . . . . . . . . 12 2.5 Decentralized

Optical performance of toric intraocular lenses in the presence of decentration.

PubMed

Zhang, Bin; Ma, Jin-Xue; Liu, Dan-Yan; Du, Ying-Hua; Guo, Cong-Rong; Cui, Yue-Xian

2015-01-01

To evaluate the optical performance of toric intraocular lenses (IOLs) after decentration and with different pupil diameters, but with the IOL astigmatic axis aligned. Optical performances of toric T5 and SN60AT spherical IOLs after decentration were tested on a theoretical pseudophakic model eye based on the Hwey-Lan Liou schematic eye using the Zemax ray-tracing program. Changes in optical performance were analyzed in model eyes with 3-mm, 4-mm, and 5-mm pupil diameters and decentered from 0.25 mm to 0.75 mm with an interval of 5° at the meridian direction from 0° to 90°. The ratio of the modulation transfer function (MTF) between a decentered and a centered IOL (MTFDecentration/MTFCentration) was calculated to analyze the decrease in optical performance. Optical performance of the toric IOL remained unchanged when IOLs were decentered in any meridian direction. The MTFs of the two IOLs decreased, whereas optical performance remained equivalent after decentration. The MTFDecentration/MTFCentration ratios of the IOLs at a decentration from 0.25 mm to 0.75 mm were comparable in the toric and SN60AT IOLs. After decentration, MTF decreased further, with the MTF of the toric IOL being slightly lower than that of the SN60AT IOL. Imaging qualities of the two IOLs decreased when the pupil diameter and the degree of decentration increased, but the decrease was similar in the toric and spherical IOLs. Toric IOLs were comparable to spherical IOLs in terms of tolerance to decentration at the correct axial position.

Optical performance of toric intraocular lenses in the presence of decentration

PubMed Central

Zhang, Bin; Ma, Jin-Xue; Liu, Dan-Yan; Du, Ying-Hua; Guo, Cong-Rong; Cui, Yue-Xian

2015-01-01

AIM To evaluate the optical performance of toric intraocular lenses (IOLs) after decentration and with different pupil diameters, but with the IOL astigmatic axis aligned. METHODS Optical performances of toric T5 and SN60AT spherical IOLs after decentration were tested on a theoretical pseudophakic model eye based on the Hwey-Lan Liou schematic eye using the Zemax ray-tracing program. Changes in optical performance were analyzed in model eyes with 3-mm, 4-mm, and 5-mm pupil diameters and decentered from 0.25 mm to 0.75 mm with an interval of 5° at the meridian direction from 0° to 90°. The ratio of the modulation transfer function (MTF) between a decentered and a centered IOL (MTFDecentration/MTFCentration) was calculated to analyze the decrease in optical performance. RESULTS Optical performance of the toric IOL remained unchanged when IOLs were decentered in any meridian direction. The MTFs of the two IOLs decreased, whereas optical performance remained equivalent after decentration. The MTFDecentration/MTFCentration ratios of the IOLs at a decentration from 0.25 mm to 0.75 mm were comparable in the toric and SN60AT IOLs. After decentration, MTF decreased further, with the MTF of the toric IOL being slightly lower than that of the SN60AT IOL. Imaging qualities of the two IOLs decreased when the pupil diameter and the degree of decentration increased, but the decrease was similar in the toric and spherical IOLs. CONCLUSIONS Toric IOLs were comparable to spherical IOLs in terms of tolerance to decentration at the correct axial position. PMID:26309871

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

PubMed

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.

Retention in Differentiated Care: Multiple Measures Analysis for a Decentralized HIV Care and Treatment Program in North Central Nigeria

PubMed Central

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. PMID:29682399

Retention in Differentiated Care: Multiple Measures Analysis for a Decentralized HIV Care and Treatment Program in North Central Nigeria.

PubMed

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

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. 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. 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). 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.

Modeling and stability of segmented reflector telescopes - A decentralized approach

NASA Technical Reports Server (NTRS)

Ryaciotaki-Boussalis, Helen A.; Ih, Che-Hang Charles

1990-01-01

The decentralization of a segmented reflector telescope based on a finite-element model of its structure is considered. The decentralization of the system at the panel level is considered. Each panel is originally treated as an isolated subsystem so that the controller design is performed independently at the local level, and then applied to the composite system for stability analysis. The panel-level control laws were designed by means of pole placement using local output feedback. Simulation results show a better 1000:1 vibration attenuation in panel position when compared to the open-loop system. It is shown that the overall closed-loop system is exponentially stable provided that certain conditions are met. The advantage to the decentralized approach is that the design is performed in terms of the low-dimensionality subsystems, thus drastically reducing the design computational complexities.

Organizational Systems Theory and Command and Control Concepts

DTIC Science & Technology

2013-03-01

Decentralized C2 • Problem is determinable • Many solutions • Predictable results • Low Risk • Slow feedback loop • Plans: Engineered or designed • C2...of these concepts in the Art of Command and the Science of Control, but lacks a proper model to assist commanders in determining how to correctly...commanders in determining how to correctly apply the concepts based on the operational environment. The paper concludes with a recommendation that the

Decentralized care for multidrug-resistant tuberculosis: a systematic review and meta-analysis.

PubMed

Ho, Jennifer; Byrne, Anthony L; Linh, Nguyen N; Jaramillo, Ernesto; Fox, Greg J

2017-08-01

To assess the effectiveness of decentralized treatment and care for patients with multidrug-resistant (MDR) tuberculosis, in comparison with centralized approaches. We searched ClinicalTrials.gov, the Cochrane library, Embase®, Google Scholar, LILACS, PubMed®, Web of Science and the World Health Organization's portal of clinical trials for studies reporting treatment outcomes for decentralized and centralized care of MDR tuberculosis. The primary outcome was treatment success. When possible, we also evaluated, death, loss to follow-up, treatment adherence and health-system costs. To obtain pooled relative risk (RR) estimates, we performed random-effects meta-analyses. Eight studies met the eligibility criteria for review inclusion. Six cohort studies, with 4026 participants in total, reported on treatment outcomes. The pooled RR estimate for decentralized versus centralized care for treatment success was 1.13 (95% CI: 1.01-1.27). The corresponding estimate for loss to follow-up was RR: 0.66 (95% CI: 0.38-1.13), for death RR: 1.01 (95% CI: 0.67-1.52) and for treatment failure was RR: 1.07 (95% CI: 0.48-2.40). Two of three studies evaluating health-care costs reported lower costs for the decentralized models of care than for the centralized models. Treatment success was more likely among patients with MDR tuberculosis treated using a decentralized approach. Further studies are required to explore the effectiveness of decentralized MDR tuberculosis care in a range of different settings.

Decentralized care for multidrug-resistant tuberculosis: a systematic review and meta-analysis

PubMed Central

Byrne, Anthony L; Linh, Nguyen N; Jaramillo, Ernesto; Fox, Greg J

2017-01-01

Abstract Objective To assess the effectiveness of decentralized treatment and care for patients with multidrug-resistant (MDR) tuberculosis, in comparison with centralized approaches. Methods We searched ClinicalTrials.gov, the Cochrane library, Embase®, Google Scholar, LILACS, PubMed®, Web of Science and the World Health Organization’s portal of clinical trials for studies reporting treatment outcomes for decentralized and centralized care of MDR tuberculosis. The primary outcome was treatment success. When possible, we also evaluated, death, loss to follow-up, treatment adherence and health-system costs. To obtain pooled relative risk (RR) estimates, we performed random-effects meta-analyses. Findings Eight studies met the eligibility criteria for review inclusion. Six cohort studies, with 4026 participants in total, reported on treatment outcomes. The pooled RR estimate for decentralized versus centralized care for treatment success was 1.13 (95% CI: 1.01–1.27). The corresponding estimate for loss to follow-up was RR: 0.66 (95% CI: 0.38–1.13), for death RR: 1.01 (95% CI: 0.67–1.52) and for treatment failure was RR: 1.07 (95% CI: 0.48–2.40). Two of three studies evaluating health-care costs reported lower costs for the decentralized models of care than for the centralized models. Conclusion Treatment success was more likely among patients with MDR tuberculosis treated using a decentralized approach. Further studies are required to explore the effectiveness of decentralized MDR tuberculosis care in a range of different settings. PMID:28804170

Effects of health care decentralization in Spain from a citizens' perspective.

PubMed

Antón, José-Ignacio; Muñoz de Bustillo, Rafael; Fernández Macías, Enrique; Rivera, Jesús

2014-05-01

The aim of this article is to analyze the impact of the decentralization of the public national health system in Spain on citizens' satisfaction with different dimensions of primary and hospital care. Using micro-data from the Health Barometer 1996-2009 and taking advantage of the exogeneity of the different pace of decentralization across Spain using a difference-in-differences strategy, we find that, in general, decentralization has not improved citizens' satisfaction with different features of the health services. In our base model, we find that there are even some small negative effects on a subset of variables. Sensitivity analysis confirms that there is no empirical evidence for supporting that decentralization has had a positive impact on citizens' satisfaction with health care. We outline several possible reasons for this.

The predictive protective control of the heat exchanger

NASA Astrophysics Data System (ADS)

Nevriva, Pavel; Filipova, Blanka; Vilimec, Ladislav

2016-06-01

The paper deals with the predictive control applied to flexible cogeneration energy system FES. FES was designed and developed by the VITKOVICE POWER ENGINEERING joint-stock company and represents a new solution of decentralized cogeneration energy sources. In FES, the heating medium is flue gas generated by combustion of a solid fuel. The heated medium is power gas, which is a gas mixture of air and water steam. Power gas is superheated in the main heat exchanger and led to gas turbines. To protect the main heat exchanger against damage by overheating, the novel predictive protective control based on the mathematical model of exchanger was developed. The paper describes the principle, the design and the simulation of the predictive protective method applied to main heat exchanger of FES.

A decentralized approach to reducing the social costs of cascading failures

NASA Astrophysics Data System (ADS)

Hines, Paul

Large cascading failures in electrical power networks come with enormous social costs. These can be direct financial costs, such as the loss of refrigerated foods in grocery stores, or more indirect social costs, such as the traffic congestion that results from the failure of traffic signals. While engineers and policy makers have made numerous technical and organizational changes to reduce the frequency and impact of large cascading failures, the existing data, as described in Chapter 2 of this work, indicate that the overall frequency and impact of large electrical blackouts in the United States are not decreasing. Motivated by the cascading failure problem, this thesis describes a new method for Distributed Model Predictive Control and a power systems application. The central goal of the method, when applied to power systems, is to reduce the social costs of cascading failures by making small, targeted reductions in load and generation and changes to generator voltage set points. Unlike some existing schemes that operate from centrally located control centers, the method is operated by software agents located at substations distributed throughout the power network. The resulting multi-agent control system is a new approach to decentralized control, combining Distributed Model Predictive Control and Reciprocal Altruism. Experimental results indicate that this scheme can in fact decrease the average size, and thus social costs, of cascading failures. Over 100 randomly generated disturbances to a model of the IEEE 300 bus test network, the method resulted in nearly an order of magnitude decrease in average event size (measured in cost) relative to cascading failure simulations without remedial control actions. Additionally, the communication requirements for the method are measured, and found to be within the bandwidth capabilities of current communications technology (on the order of 100kB/second). Experiments on several resistor networks with varying structures, including a random graph, a scale-free network and a power grid indicate that the effectiveness of decentralized control schemes, like the method proposed here, is a function of the structure of the network that is to be controlled.

Prehospital factors determining regional variation in thrombolytic therapy in acute ischemic stroke.

PubMed

Lahr, Maarten M H; Vroomen, Patrick C A J; Luijckx, Gert-Jan; van der Zee, Durk-Jouke; de Vos, Ronald; Buskens, Erik

2014-10-01

Treatment rates with intravenous tissue plasminogen activator vary by region, which can be partially explained by organizational models of stroke care. A recent study demonstrated that prehospital factors determine a higher thrombolysis rate in a centralized vs. decentralized model in the north of the Netherlands. To investigate prehospital factors that may explain variation in thrombolytic therapy between a centralized and a decentralized model. A consecutive case observational study was conducted in the north of the Netherlands comparing patients arriving within 4·5 h in a centralized vs. decentralized stroke care model. Factors investigated were transportation mode, prehospital diagnostic accuracy, and preferential referral of thrombolysis candidates. Potential confounders were adjusted using logistic regression analysis. A total of 172 and 299 arriving within 4·5 h were enrolled in centralized and decentralized settings, respectively. The rate of transportation by emergency medical services was greater in the centralized model (adjusted odds ratio 3·11; 95% confidence interval, 1·59-6·06). Also, more misdiagnoses of stroke occurred in the central model (P = 0·05). In postal code areas with and without potential preferential referral of thrombolysis candidates due to overlapping catchment areas, the odds of hospital arrival within 4·5 h in the central vs. decentral model were 2·15 (95% confidence interval, 1·39-3·32) and 1·44 (95% confidence interval, 1·04-2·00), respectively. These results suggest that the larger proportion of patients arriving within 4·5 h in the centralized model might be related to a lower threshold to use emergency services to transport stroke patients and partly to preferential referral of thrombolysis candidates. © 2013 The Authors. International Journal of Stroke © 2013 World Stroke Organization.

An empirical examination of the impacts of decentralized nursing unit design.

PubMed

Pati, Debajyoti; Harvey, Thomas E; Redden, Pamela; Summers, Barbara; Pati, Sipra

2015-01-01

The objective of the study was to examine the impact of decentralization on operational efficiency, staff well-being, and teamwork on three inpatient units. Decentralized unit operations and the corresponding physical design solution were hypothesized to positively affect several concerns-productive use of nursing time, staff stress, walking distances, and teamwork, among others. With a wide adoption of the concept, empirical evidence on the impact of decentralization was warranted. A multimethod, before-and-after, quasi-experimental design was adopted for the study, focusing on five issues, namely, (1) how nurses spend their time, (2) walking distance, (3) acute stress, (4) productivity, and (5) teamwork. Data on all five issues were collected on three older units with centralized operational model (before move). The same set of data, with identical tools and measures, were collected on the same units after move in to new physical units with decentralized operational model. Data were collected during spring and fall of 2011. Documentation, nurse station use, medication room use, and supplies room use showed consistent change across the three units. Walking distance increased (statistically significant) on two of the three units. Self-reported level of collaboration decreased, although assessment of the physical facility for collaboration increased. Decentralized nursing and physical design models potentially result in quality of work improvements associated with documentation, medication, and supplies. However, there are unexpected consequences associated with walking, and staff collaboration and teamwork. The solution to the unexpected consequences may lie in operational interventions and greater emphasis on culture change. © The Author(s) 2015.

Outcome assessment of decentralization of antiretroviral therapy provision in a rural district of Malawi using an integrated primary care model.

PubMed

Chan, Adrienne K; Mateyu, Gabriel; Jahn, Andreas; Schouten, Erik; Arora, Paul; Mlotha, William; Kambanji, Marion; van Lettow, Monique

2010-06-01

To assess the effect of decentralization (DC) of antiretroviral therapy (ART) provision in a rural district of Malawi using an integrated primary care model. Between October 2004 and December 2008, 8093 patients (63% women) were registered for ART. Of these, 3440 (43%) were decentralized to health centres for follow-up ART care. We applied multivariate regression analysis that adjusted for sex, age, clinical stage at initiation, type of regimen, presence of side effects because of ART, and duration of treatment and follow-up at site of analysis. Patients managed at health centres had lower mortality [adjusted OR 0.19 (95% C.I. 0.15-0.25)] and lower loss to follow-up (defaulted from treatment) [adjusted OR 0.48 (95% C.I. 0.40-0.58)]. During the first 10 months of follow-up, those decentralized to health centres were approximately 60% less likely to default than those not decentralized; and after 10 months of follow-up, 40% less likely to default. DC was significantly associated with a reduced risk of death from 0 to 25 months of follow-up. The lower mortality may be explained by the selection of stable patients for DC, and the mentorship and supportive supervision of lower cadre health workers to identify and refer complicated cases. Decentralization of follow-up ART care to rural health facilities, using an integrated primary care model, appears a safe and effective way to rapidly scale-up ART and improves both geographical equity in access to HIV-related services and adherence to ART.

Fuzzy bilevel programming with multiple non-cooperative followers: model, algorithm and application

NASA Astrophysics Data System (ADS)

Ke, Hua; Huang, Hu; Ralescu, Dan A.; Wang, Lei

2016-04-01

In centralized decision problems, it is not complicated for decision-makers to make modelling technique selections under uncertainty. When a decentralized decision problem is considered, however, choosing appropriate models is no longer easy due to the difficulty in estimating the other decision-makers' inconclusive decision criteria. These decision criteria may vary with different decision-makers because of their special risk tolerances and management requirements. Considering the general differences among the decision-makers in decentralized systems, we propose a general framework of fuzzy bilevel programming including hybrid models (integrated with different modelling methods in different levels). Specially, we discuss two of these models which may have wide applications in many fields. Furthermore, we apply the proposed two models to formulate a pricing decision problem in a decentralized supply chain with fuzzy coefficients. In order to solve these models, a hybrid intelligent algorithm integrating fuzzy simulation, neural network and particle swarm optimization based on penalty function approach is designed. Some suggestions on the applications of these models are also presented.

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

NASA Technical Reports Server (NTRS)

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.

A survey of decentralized control techniques for large space structures

NASA Technical Reports Server (NTRS)

Lindner, D. K.; Reichard, K.

1987-01-01

Preliminary results on the design of decentralized controllers for the COFS I Mast are reported. A nine mode finite element model is used along with second order model of the actuators. It is shown that without actuator dynamics, the system is stable with collocated rate feedback and has acceptable performace. However, when actuator dynamics are included, the system is unstable.

Decentralized digital adaptive control of robot motion

NASA Technical Reports Server (NTRS)

Tarokh, M.

1990-01-01

A decentralized model reference adaptive scheme is developed for digital control of robot manipulators. The adaptation laws are derived using hyperstability theory, which guarantees asymptotic trajectory tracking despite gross robot parameter variations. The control scheme has a decentralized structure in the sense that each local controller receives only its joint angle measurement to produce its joint torque. The independent joint controllers have simple structures and can be programmed using a very simple and computationally fast algorithm. As a result, the scheme is suitable for real-time motion control.

Optimizing decentralized production-distribution planning problem in a multi-period supply chain network under uncertainty

NASA Astrophysics Data System (ADS)

Nourifar, Raheleh; Mahdavi, Iraj; Mahdavi-Amiri, Nezam; Paydar, Mohammad Mahdi

2017-09-01

Decentralized supply chain management is found to be significantly relevant in today's competitive markets. Production and distribution planning is posed as an important optimization problem in supply chain networks. Here, we propose a multi-period decentralized supply chain network model with uncertainty. The imprecision related to uncertain parameters like demand and price of the final product is appropriated with stochastic and fuzzy numbers. We provide mathematical formulation of the problem as a bi-level mixed integer linear programming model. Due to problem's convolution, a structure to solve is developed that incorporates a novel heuristic algorithm based on Kth-best algorithm, fuzzy approach and chance constraint approach. Ultimately, a numerical example is constructed and worked through to demonstrate applicability of the optimization model. A sensitivity analysis is also made.

A discrete decentralized variable structure robotic controller

NASA Technical Reports Server (NTRS)

Tumeh, Zuheir S.

1989-01-01

A decentralized trajectory controller for robotic manipulators is designed and tested using a multiprocessor architecture and a PUMA 560 robot arm. The controller is made up of a nominal model-based component and a correction component based on a variable structure suction control approach. The second control component is designed using bounds on the difference between the used and actual values of the model parameters. Since the continuous manipulator system is digitally controlled along a trajectory, a discretized equivalent model of the manipulator is used to derive the controller. The motivation for decentralized control is that the derived algorithms can be executed in parallel using a distributed, relatively inexpensive, architecture where each joint is assigned a microprocessor. Nonlinear interaction and coupling between joints is treated as a disturbance torque that is estimated and compensated for.

Indirect decentralized repetitive control

NASA Technical Reports Server (NTRS)

Lee, Soo Cheol; Longman, Richard W.

1993-01-01

Learning control refers to controllers that learn to improve their performance at executing a given task, based on experience performing this specific task. In a previous work, the authors presented a theory of indirect decentralized learning control based on use of indirect adaptive control concepts employing simultaneous identification and control. This paper extends these results to apply to the indirect repetitive control problem in which a periodic (i.e., repetitive) command is given to a control system. Decentralized indirect repetitive control algorithms are presented that have guaranteed convergence to zero tracking error under very general conditions. The original motivation of the repetitive control and learning control fields was learning in robots doing repetitive tasks such as on an assembly line. This paper starts with decentralized discrete time systems, and progresses to the robot application, modeling the robot as a time varying linear system in the neighborhood of the desired trajectory. Decentralized repetitive control is natural for this application because the feedback control for link rotations is normally implemented in a decentralized manner, treating each link as if it is independent of the other links.

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

ERIC Educational Resources Information Center

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…

[Decentralized outpatient teams in community-based psychiatric care: comparison of two Bavarian rural catchment areas].

PubMed

Valdes-Stauber, J; Putzhammer, A; Kilian, R

2014-05-01

Psychiatric outpatient clinics (PIAs) are an indispensable care service for crisis intervention and multidisciplinary treatment of people suffering from severe and persistent mental disorders. The decentralization of outpatient clinics can be understood as a further step in the deinstitutionalization process. This cross-sectional study (n=1,663) compared the central outpatient clinic with the decentralized teams for the year 2010 by means of analyses of variance, χ(2)-tests and robust multivariate regression models. The longitudinal assessment (descriptively and by means of Prais-Winsten regression models for time series) was based on all hospitalizations for the two decentralized teams (n = 6,693) according to partial catchment areas for the time period 2002-2010 in order to examine trends after their installation in the year 2007. Decentralized teams were found to be similar with respect to the care profile but cared for relatively more patients suffering from dementia, addictive and mood disorders but not for those suffering from schizophrenia and personality disorders. Decentralized teams showed less outpatient care costs as well as psychopharmacological expenses but a lower contact frequency than the central outpatient clinic. Total expenses for psychiatric care were not significantly different and assessed hospitalization variables (e.g. total number of annual admissions, cumulative length of inpatient-stay and annual hospitalizations per patient) changed slightly 3 years after installation of the decentralized teams. The number of admissions of people suffering from schizophrenia decreased whereas those for mood and stress disorders increased. Decentralized outpatient teams seemed to reach patients in rural regions who previously were not reached by the central outpatient clinic. Economic figures indicate advantages for the installation of such teams because care expenses are not higher than for patients treated in centralized outpatient clinics and because hospitalization figures for the whole catchment area did not increase.

Sting, Carry and Stock: How Corpse Availability Can Regulate De-Centralized Task Allocation in a Ponerine Ant Colony

PubMed Central

Schmickl, Thomas; Karsai, Istvan

2014-01-01

We develop a model to produce plausible patterns of task partitioning in the ponerine ant Ectatomma ruidum based on the availability of living prey and prey corpses. The model is based on the organizational capabilities of a “common stomach” through which the colony utilizes the availability of a natural (food) substance as a major communication channel to regulate the income and expenditure of the very same substance. This communication channel has also a central role in regulating task partitioning of collective hunting behavior in a supply&demand-driven manner. Our model shows that task partitioning of the collective hunting behavior in E. ruidum can be explained by regulation due to a common stomach system. The saturation of the common stomach provides accessible information to individual ants so that they can adjust their hunting behavior accordingly by engaging in or by abandoning from stinging or transporting tasks. The common stomach is able to establish and to keep stabilized an effective mix of workforce to exploit the prey population and to transport food into the nest. This system is also able to react to external perturbations in a de-centralized homeostatic way, such as to changes in the prey density or to accumulation of food in the nest. In case of stable conditions the system develops towards an equilibrium concerning colony size and prey density. Our model shows that organization of work through a common stomach system can allow Ectatomma ruidum to collectively forage for food in a robust, reactive and reliable way. The model is compared to previously published models that followed a different modeling approach. Based on our model analysis we also suggest a series of experiments for which our model gives plausible predictions. These predictions are used to formulate a set of testable hypotheses that should be investigated empirically in future experimentation. PMID:25493558

Decentralized model reference adaptive control of large flexible structures

NASA Technical Reports Server (NTRS)

Lee, Fu-Ming; Fong, I-Kong; Lin, Yu-Hwan

1988-01-01

A decentralized model reference adaptive control (DMRAC) method is developed for large flexible structures (LFS). The development follows that of a centralized model reference adaptive control for LFS that have been shown to be feasible. The proposed method is illustrated using a simply supported beam with collocated actuators and sensors. Results show that the DMRAC can achieve either output regulation or output tracking with adequate convergence, provided the reference model inputs and their time derivatives are integrable, bounded, and approach zero as t approaches infinity.

Partially Decentralized Control Architectures for Satellite Formations

NASA Technical Reports Server (NTRS)

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.

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

PubMed

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.

Optimizing Natural Gas Networks through Dynamic Manifold Theory and a Decentralized Algorithm: Belgium Case Study

NASA Astrophysics Data System (ADS)

Koch, Caleb; Winfrey, Leigh

2014-10-01

Natural Gas is a major energy source in Europe, yet political instabilities have the potential to disrupt access and supply. Energy resilience is an increasingly essential construct and begins with transmission network design. This study proposes a new way of thinking about modelling natural gas flow. Rather than relying on classical economic models, this problem is cast into a time-dependent Hamiltonian dynamics discussion. Traditional Natural Gas constraints, including inelastic demand and maximum/minimum pipe flows, are portrayed as energy functions and built into the dynamics of each pipe flow. Doing so allows the constraints to be built into the dynamics of each pipeline. As time progresses in the model, natural gas flow rates find the minimum energy, thus the optimal gas flow rates. The most important result of this study is using dynamical principles to ensure the output of natural gas at demand nodes remains constant, which is important for country to country natural gas transmission. Another important step in this study is building the dynamics of each flow in a decentralized algorithm format. Decentralized regulation has solved congestion problems for internet data flow, traffic flow, epidemiology, and as demonstrated in this study can solve the problem of Natural Gas congestion. A mathematical description is provided for how decentralized regulation leads to globally optimized network flow. Furthermore, the dynamical principles and decentralized algorithm are applied to a case study of the Fluxys Belgium Natural Gas Network.

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

ERIC Educational Resources Information Center

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…

Leadership and the Decentralized Control of Schools

ERIC Educational Resources Information Center

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…

Decentralized Patrolling Under Constraints in Dynamic Environments.

PubMed

Shaofei Chen; Feng Wu; Lincheng Shen; Jing Chen; Ramchurn, Sarvapali D

2016-12-01

We investigate a decentralized patrolling problem for dynamic environments where information is distributed alongside threats. In this problem, agents obtain information at a location, but may suffer attacks from the threat at that location. In a decentralized fashion, each agent patrols in a designated area of the environment and interacts with a limited number of agents. Therefore, the goal of these agents is to coordinate to gather as much information as possible while limiting the damage incurred. Hence, we model this class of problem as a transition-decoupled partially observable Markov decision process with health constraints. Furthermore, we propose scalable decentralized online algorithms based on Monte Carlo tree search and a factored belief vector. We empirically evaluate our algorithms on decentralized patrolling problems and benchmark them against the state-of-the-art online planning solver. The results show that our approach outperforms the state-of-the-art by more than 56% for six agents patrolling problems and can scale up to 24 agents in reasonable time.

Decentralized indirect methods for learning automata games.

PubMed

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.

Transition-Independent Decentralized Markov Decision Processes

NASA Technical Reports Server (NTRS)

Becker, Raphen; Silberstein, Shlomo; Lesser, Victor; Goldman, Claudia V.; Morris, Robert (Technical Monitor)

2003-01-01

There has been substantial progress with formal models for sequential decision making by individual agents using the Markov decision process (MDP). However, similar treatment of multi-agent systems is lacking. A recent complexity result, showing that solving decentralized MDPs is NEXP-hard, provides a partial explanation. To overcome this complexity barrier, we identify a general class of transition-independent decentralized MDPs that is widely applicable. The class consists of independent collaborating agents that are tied up by a global reward function that depends on both of their histories. We present a novel algorithm for solving this class of problems and examine its properties. The result is the first effective technique to solve optimally a class of decentralized MDPs. This lays the foundation for further work in this area on both exact and approximate solutions.

A Statewide Decentralized Approach to Public School Reform: The Case of Career Ladders in Utah.

ERIC Educational Resources Information Center

Malen, Betty; Murphy, Michael J.

1985-01-01

In 1984, the Utah legislature enacted a career ladder bill encouraging all local districts to develop plans for restructuring teachers' compensation and promotion options. An independent, bipartisan taskforce then created a statewide, decentralized model that increases educators' power, minimizes merit and staff differentiation, and fosters…

From decentralization to commonization of HIV healthcare resources: keys to reduction in health disparity and equitable distribution of health services in Nigeria.

PubMed

Oleribe, Obinna Ositadimma; Oladipo, Olabisi Abiodun; Ezieme, Iheaka Paul; Crossey, Mary Margaret Elizabeth; Taylor-Robinson, Simon David

2016-01-01

Access to quality care is essential for improved health outcomes. Decentralization improves access to healthcare services at lower levels of care, but it does not dismantle structural, funding and programming restrictions to access, resulting in inequity and inequality in population health. Unlike decentralization, Commonization Model of care reduces health inequalities and inequity, dismantles structural, funding and other program related obstacles to population health. Excellence and Friends Management Care Center (EFMC) using Commonization Model (CM), fully integrated HIV services into core health services in 121 supported facilities. This initiative improved access to care, treatment, support services, reduced stigmatization/discrimination, and improved uptake of HTC. We call on governments to adequately finance CM for health systems restructuring towards better health outcomes.

Centralized, decentralized, and independent control of a flexible manipulator on a flexible base

NASA Technical Reports Server (NTRS)

Li, Feiyue; Bainum, Peter M.; Xu, Jianke

1991-01-01

The dynamics and control of a flexible manipulator arm with payload mass on a flexible base in space are considered. The controllers are provided by one torquer at the center of the base and one torquer at the connection joint of the robot and the base. The nonlinear dynamics of the system is modeled by applying the finite element method and Lagrangian formula. Three control strategies are considered and compared, i.e., centralized control, decentralized control, and independent control. All these control designs are based on the linear quadratic regulator theory. A mathematical decomposition is used in the decentralization process so that the coupling between the subsystems is weak, while a physical decomposition is used in the independent control design process. For both the decentralized and the independent controls, the stability of the overall linear system is checked before a numerical simulations is initiated. Two numerical examples show that the response of the independent control system are close to those of the centralized control system, while the responses of the decentralized control system are not.

Perturbed cooperative-state feedback strategy for model predictive networked control of interconnected systems.

PubMed

Tran, Tri; Ha, Q P

2018-01-01

A perturbed cooperative-state feedback (PSF) strategy is presented for the control of interconnected systems in this paper. The subsystems of an interconnected system can exchange data via the communication network that has multiple connection topologies. The PSF strategy can resolve both issues, the sensor data losses and the communication network breaks, thanks to the two components of the control including a cooperative-state feedback and a perturbation variable, e.g., u i =K ij x j +w i . The PSF is implemented in a decentralized model predictive control scheme with a stability constraint and a non-monotonic storage function (ΔV(x(k))≥0), derived from the dissipative systems theory. Numerical simulation for the automatic generation control problem in power systems is studied to illustrate the effectiveness of the presented PSF strategy. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

Hierarchical Management Information Systems: A Decentralized Approach for University Administration

ERIC Educational Resources Information Center

Wager, J. James

1977-01-01

A Hierarchical Management Information System (HMIS) provides decision-making as well as operational information to all groups of the institution in a timely and predictable manner. Its operational aspects and benefits are discussed. (Author/LBH)

Model-Based Design of Tree WSNs for Decentralized Detection.

PubMed

Tantawy, Ashraf; Koutsoukos, Xenofon; Biswas, Gautam

2015-08-20

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.

Substructural controller synthesis

NASA Technical Reports Server (NTRS)

Su, Tzu-Jeng; Craig, Roy R., Jr.

1989-01-01

A decentralized design procedure which combines substructural synthesis, model reduction, decentralized controller design, subcontroller synthesis, and controller reduction is proposed for the control design of flexible structures. The structure to be controlled is decomposed into several substructures, which are modeled by component mode synthesis methods. For each substructure, a subcontroller is designed by using the linear quadratic optimal control theory. Then, a controller synthesis scheme called Substructural Controller Synthesis (SCS) is used to assemble the subcontrollers into a system controller, which is to be used to control the whole structure.

Decentralized Feedback Controllers for Robust Stabilization of Periodic Orbits of Hybrid Systems: Application to Bipedal Walking.

PubMed

Hamed, Kaveh Akbari; Gregg, Robert D

2017-07-01

This paper presents a systematic algorithm to design time-invariant decentralized feedback controllers to exponentially and robustly stabilize periodic orbits for hybrid dynamical systems against possible uncertainties in discrete-time phases. The algorithm assumes a family of parameterized and decentralized nonlinear controllers to coordinate interconnected hybrid subsystems based on a common phasing variable. The exponential and [Formula: see text] robust stabilization problems of periodic orbits are translated into an iterative sequence of optimization problems involving bilinear and linear matrix inequalities. By investigating the properties of the Poincaré map, some sufficient conditions for the convergence of the iterative algorithm are presented. The power of the algorithm is finally demonstrated through designing a set of robust stabilizing local nonlinear controllers for walking of an underactuated 3D autonomous bipedal robot with 9 degrees of freedom, impact model uncertainties, and a decentralization scheme motivated by amputee locomotion with a transpelvic prosthetic leg.

Decentralized and Tactical Air Traffic Flow Management

NASA Technical Reports Server (NTRS)

Odoni, Amedeo R.; Bertsimas, Dimitris

1997-01-01

This project dealt with the following topics: 1. Review and description of the existing air traffic flow management system (ATFM) and identification of aspects with potential for improvement. 2. Identification and review of existing models and simulations dealing with all system segments (enroute, terminal area, ground) 3. Formulation of concepts for overall decentralization of the ATFM system, ranging from moderate decentralization to full decentralization 4. Specification of the modifications to the ATFM system required to accommodate each of the alternative concepts. 5. Identification of issues that need to be addressed with regard to: determination of the way the ATFM system would be operating; types of flow management strategies that would be used; and estimation of the effectiveness of ATFM with regard to reducing delay and re-routing costs. 6. Concept evaluation through identification of criteria and methodologies for accommodating the interests of stakeholders and of approaches to optimization of operational procedures for all segments of the ATFM system.

Decentralized Feedback Controllers for Robust Stabilization of Periodic Orbits of Hybrid Systems: Application to Bipedal Walking

PubMed Central

Hamed, Kaveh Akbari; Gregg, Robert D.

2016-01-01

This paper presents a systematic algorithm to design time-invariant decentralized feedback controllers to exponentially and robustly stabilize periodic orbits for hybrid dynamical systems against possible uncertainties in discrete-time phases. The algorithm assumes a family of parameterized and decentralized nonlinear controllers to coordinate interconnected hybrid subsystems based on a common phasing variable. The exponential and H2 robust stabilization problems of periodic orbits are translated into an iterative sequence of optimization problems involving bilinear and linear matrix inequalities. By investigating the properties of the Poincaré map, some sufficient conditions for the convergence of the iterative algorithm are presented. The power of the algorithm is finally demonstrated through designing a set of robust stabilizing local nonlinear controllers for walking of an underactuated 3D autonomous bipedal robot with 9 degrees of freedom, impact model uncertainties, and a decentralization scheme motivated by amputee locomotion with a transpelvic prosthetic leg. PMID:28959117

Application of decentralized cooperative problem solving in dynamic flexible scheduling

NASA Astrophysics Data System (ADS)

Guan, Zai-Lin; Lei, Ming; Wu, Bo; Wu, Ya; Yang, Shuzi

1995-08-01

The object of this study is to discuss an intelligent solution to the problem of task-allocation in shop floor scheduling. For this purpose, the technique of distributed artificial intelligence (DAI) is applied. Intelligent agents (IAs) are used to realize decentralized cooperation, and negotiation is realized by using message passing based on the contract net model. Multiple agents, such as manager agents, workcell agents, and workstation agents, make game-like decisions based on multiple criteria evaluations. This procedure of decentralized cooperative problem solving makes local scheduling possible. And by integrating such multiple local schedules, dynamic flexible scheduling for the whole shop floor production can be realized.

Interaction Metrics for Feedback Control of Sound Radiation from Stiffened Panels

NASA Technical Reports Server (NTRS)

Cabell, Randolph H.; Cox, David E.; Gibbs, Gary P.

2003-01-01

Interaction metrics developed for the process control industry are used to evaluate decentralized control of sound radiation from bays on an aircraft fuselage. The metrics are applied to experimentally measured frequency response data from a model of an aircraft fuselage. The purpose is to understand how coupling between multiple bays of the fuselage can destabilize or limit the performance of a decentralized active noise control system. The metrics quantitatively verify observations from a previous experiment, in which decentralized controllers performed worse than centralized controllers. The metrics do not appear to be useful for explaining control spillover which was observed in a previous experiment.

Simulating the decentralized processes of the human immune system in a virtual anatomy model.

PubMed

Sarpe, Vladimir; Jacob, Christian

2013-01-01

Many physiological processes within the human body can be perceived and modeled as large systems of interacting particles or swarming agents. The complex processes of the human immune system prove to be challenging to capture and illustrate without proper reference to the spatial distribution of immune-related organs and systems. Our work focuses on physical aspects of immune system processes, which we implement through swarms of agents. This is our first prototype for integrating different immune processes into one comprehensive virtual physiology simulation. Using agent-based methodology and a 3-dimensional modeling and visualization environment (LINDSAY Composer), we present an agent-based simulation of the decentralized processes in the human immune system. The agents in our model - such as immune cells, viruses and cytokines - interact through simulated physics in two different, compartmentalized and decentralized 3-dimensional environments namely, (1) within the tissue and (2) inside a lymph node. While the two environments are separated and perform their computations asynchronously, an abstract form of communication is allowed in order to replicate the exchange, transportation and interaction of immune system agents between these sites. The distribution of simulated processes, that can communicate across multiple, local CPUs or through a network of machines, provides a starting point to build decentralized systems that replicate larger-scale processes within the human body, thus creating integrated simulations with other physiological systems, such as the circulatory, endocrine, or nervous system. Ultimately, this system integration across scales is our goal for the LINDSAY Virtual Human project. Our current immune system simulations extend our previous work on agent-based simulations by introducing advanced visualizations within the context of a virtual human anatomy model. We also demonstrate how to distribute a collection of connected simulations over a network of computers. As a future endeavour, we plan to use parameter tuning techniques on our model to further enhance its biological credibility. We consider these in silico experiments and their associated modeling and optimization techniques as essential components in further enhancing our capabilities of simulating a whole-body, decentralized immune system, to be used both for medical education and research as well as for virtual studies in immunoinformatics.

Adaptive Decentralized Control

DTIC Science & Technology

1985-04-01

and implementation of the decentralized controllers. It raises, however, many difficult questions regarding the conditions under which such a scheme ...adaptive controller, and a general form of the model reference adaptive controller (4]. We believe that this work represents a significant advance in the...Comparing the adaptive system with the tuned system results in the development of a generic adaptive error system. Passivity theory was used to derive

Evolutionary Concepts for Decentralized Air Traffic Flow Management

NASA Technical Reports Server (NTRS)

Adams, Milton; Kolitz, Stephan; Milner, Joseph; Odoni, Amedeo

1997-01-01

Alternative concepts for modifying the policies and procedures under which the air traffic flow management system operates are described, and an approach to the evaluation of those concepts is discussed. Here, air traffic flow management includes all activities related to the management of the flow of aircraft and related system resources from 'block to block.' The alternative concepts represent stages in the evolution from the current system, in which air traffic management decision making is largely centralized within the FAA, to a more decentralized approach wherein the airlines and other airspace users collaborate in air traffic management decision making with the FAA. The emphasis in the discussion is on a viable medium-term partially decentralized scenario representing a phase of this evolution that is consistent with the decision-making approaches embodied in proposed Free Flight concepts for air traffic management. System-level metrics for analyzing and evaluating the various alternatives are defined, and a simulation testbed developed to generate values for those metrics is described. The fundamental issue of modeling airline behavior in decentralized environments is also raised, and an example of such a model, which deals with the preservation of flight bank integrity in hub airports, is presented.

Investigating the interactions of decentralized and centralized wastewater heat recovery systems.

PubMed

Sitzenfrei, Robert; Hillebrand, Sebastian; Rauch, Wolfgang

2017-03-01

In the urban water cycle there are different sources for extracting energy. In addition to potential and chemical energy in the wastewater, thermal energy can also be recovered. Heat can be recovered from the wastewater with heat exchangers that are located decentralized and/or centralized at several locations throughout the system. It can be recovered directly at the source (e.g. in the showers and bathrooms), at building block level (e.g. warm water tanks collecting all grey water), in sewers or at the wastewater treatment plant. However, an uncoordinated installation of systems on such different levels can lead to competing technologies. To investigate these interactions, a modelling environment is set up, tested and calibrated based on continuous sewer temperature and flow measurements. With that approach different heat recovery scenarios on a household level (decentralized) and of in-sewer heat recovery (centralized) are investigated. A maximum performance drop of 40% for a centralized energy recovery system was estimated when all bathrooms are equipped with decentralized recovery systems. Therefore, the proposed modelling approach is suitable for testing different future conditions and to identify robust strategies for heat recovery systems from wastewater.

Decentralized nursing education in northern Norway: a basis for continuing education to meet competence needs in rural Arctic healthcare services.

PubMed

Skaalvik, Mari Wolff; Gaski, Margrete; Norbye, Bente

2014-01-01

Ensuring a sufficient nursing workforce, with respect to both number and relevant professional competencies, is crucial in rural Arctic regions in Norway. This study examines the continuing education (CE) of nurses who graduated from a decentralized nursing programme between 1994 and 2011. This study aims to measure the extent to which the decentralized nursing education (DNE) in question has served as a basis for CE that is adapted to current and future community health care service needs in rural Arctic regions in northern Norway. More specifically, the study aims to investigate the frequency and scope of CE courses among the graduates of a DNE, the choice of study model and the degree of employment with respect to the relevant CE. This study is a quantitative survey providing descriptive statistics. The primary finding in this study is that 56% of the participants had engaged in CE and that they were employed in positions related to their education. The majority of students with decentralized bachelor's degrees engaged in CE that was part time and/or decentralized. More than half of the population in this study had completed CE despite no mandatory obligation in order to maintain licensure. Furthermore, 31% of the participants had completed more than one CE programme. The findings show that the participants preferred CE organized as part time and or decentralized studies.

Impacts of Combined Cooling, Heating and Power Systems, and Rainwater Harvesting on Water Demand, Carbon Dioxide, and NOx Emissions for Atlanta.

PubMed

James, Jean-Ann; Sung, Sangwoo; Jeong, Hyunju; Broesicke, Osvaldo A; French, Steven P; Li, Duo; Crittenden, John C

2018-01-02

The purpose of this study is to explore the potential water, CO 2 and NO x emission, and cost savings that the deployment of decentralized water and energy technologies within two urban growth scenarios can achieve. We assess the effectiveness of urban growth, technological, and political strategies to reduce these burdens in the 13-county Atlanta metropolitan region. The urban growth between 2005 and 2030 was modeled for a business as usual (BAU) scenario and a more compact growth (MCG) scenario. We considered combined cooling, heating and power (CCHP) systems using microturbines for our decentralized energy technology and rooftop rainwater harvesting and low flow fixtures for the decentralized water technologies. Decentralized water and energy technologies had more of an impact in reducing the CO 2 and NO x emissions and water withdrawal and consumption than an MCG growth scenario (which does not consider energy for transit). Decentralized energy can reduce the CO 2 and NO x emissions by 8% and 63%, respectively. Decentralized energy and water technologies can reduce the water withdrawal and consumption in the MCG scenario by 49% and 50% respectively. Installing CCHP systems on both the existing and new building stocks with a net metering policy could reduce the CO 2 , NO x , and water consumption by 50%, 90%, and 75% respectively.

Integrated control strategy for autonomous decentralized conveyance systems based on distributed MEMS arrays

NASA Astrophysics Data System (ADS)

Zhou, Lingfei; Chapuis, Yves-Andre; Blonde, Jean-Philippe; Bervillier, Herve; Fukuta, Yamato; Fujita, Hiroyuki

2004-07-01

In this paper, the authors proposed to study a model and a control strategy of a two-dimensional conveyance system based on the principles of the Autonomous Decentralized Microsystems (ADM). The microconveyance system is based on distributed cooperative MEMS actuators which can produce a force field onto the surface of the device to grip and move a micro-object. The modeling approach proposed here is based on a simple model of a microconveyance system which is represented by a 5 x 5 matrix of cells. Each cell is consisted of a microactuator, a microsensor, and a microprocessor to provide actuation, autonomy and decentralized intelligence to the cell. Thus, each cell is able to identify a micro-object crossing on it and to decide by oneself the appropriate control strategy to convey the micro-object to its destination target. The control strategy could be established through five simple decision rules that the cell itself has to respect at each calculate cycle time. Simulation and FPGA implementation results are given in the end of the paper in order to validate model and control approach of the microconveyance system.

Decentralized control experiments on NASA's flexible grid

NASA Technical Reports Server (NTRS)

Ozguner, U.; Yurkowich, S.; Martin, J., III; Al-Abbass, F.

1986-01-01

Methods arising from the area of decentralized control are emerging for analysis and control synthesis for large flexible structures. In this paper the control strategy involves a decentralized model reference adaptive approach using a variable structure control. Local models are formulated based on desired damping and response time in a model-following scheme for various modal configurations. Variable structure controllers are then designed employing co-located angular rate and position feedback. In this scheme local control forces the system to move on a local sliding mode in some local error space. An important feature of this approach is that the local subsystem is made insensitive to dynamical interactions with other subsystems once the sliding surface is reached. Experiments based on the above have been performed for NASA's flexible grid experimental apparatus. The grid is designed to admit appreciable low-frequency structural dynamics, and allows for implementation of distributed computing components, inertial sensors, and actuation devices. A finite-element analysis of the grid provides the model for control system design and simulation; results of several simulations are reported on here, and a discussion of application experiments on the apparatus is presented.

Model-Based Design of Tree WSNs for Decentralized Detection †

PubMed Central

Tantawy, Ashraf; Koutsoukos, Xenofon; Biswas, Gautam

2015-01-01

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. PMID:26307989

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

PubMed

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.

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

PubMed

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.

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

PubMed

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.

Indirect decentralized learning control

NASA Technical Reports Server (NTRS)

Longman, Richard W.; Lee, Soo C.; Phan, M.

1992-01-01

The new field of learning control develops controllers that learn to improve their performance at executing a given task, based on experience performing this specific task. In a previous work, the authors presented a theory of indirect learning control based on use of indirect adaptive control concepts employing simultaneous identification and control. This paper develops improved indirect learning control algorithms, and studies the use of such controllers in decentralized systems. The original motivation of the learning control field was learning in robots doing repetitive tasks such as on an assembly line. This paper starts with decentralized discrete time systems, and progresses to the robot application, modeling the robot as a time varying linear system in the neighborhood of the nominal trajectory, and using the usual robot controllers that are decentralized, treating each link as if it is independent of any coupling with other links. The basic result of the paper is to show that stability of the indirect learning controllers for all subsystems when the coupling between subsystems is turned off, assures convergence to zero tracking error of the decentralized indirect learning control of the coupled system, provided that the sample time in the digital learning controller is sufficiently short.

Decentralized Real-Time Scheduling

DTIC Science & Technology

1990-08-01

must provide several alternative resource management policies, including FIFO and deadline queueing for shared resources that are not available. 5...When demand exceeds the supply of shared resources (even within a single switch), some calls cannot be completed. In that case, a call’s priority...associated chiefly with the need to manage resources in a timely and decentralized fashion. The Alpha programming model permits the convenient expression of

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

PubMed

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.

Agent-based Modeling to Simulate the Diffusion of Water-Efficient Innovations and the Emergence of Urban Water Sustainability

NASA Astrophysics Data System (ADS)

Kanta, L.; Giacomoni, M.; Shafiee, M. E.; Berglund, E.

2014-12-01

The sustainability of water resources is threatened by urbanization, as increasing demands deplete water availability, and changes to the landscape alter runoff and the flow regime of receiving water bodies. Utility managers typically manage urban water resources through the use of centralized solutions, such as large reservoirs, which may be limited in their ability balance the needs of urbanization and ecological systems. Decentralized technologies, on the other hand, may improve the health of the water resources system and deliver urban water services. For example, low impact development technologies, such as rainwater harvesting, and water-efficient technologies, such as low-flow faucets and toilets, may be adopted by households to retain rainwater and reduce demands, offsetting the need for new centralized infrastructure. Decentralized technologies may create new complexities in infrastructure and water management, as decentralization depends on community behavior and participation beyond traditional water resources planning. Messages about water shortages and water quality from peers and the water utility managers can influence the adoption of new technologies. As a result, feedbacks between consumers and water resources emerge, creating a complex system. This research develops a framework to simulate the diffusion of water-efficient innovations and the sustainability of urban water resources, by coupling models of households in a community, hydrologic models of a water resources system, and a cellular automata model of land use change. Agent-based models are developed to simulate the land use and water demand decisions of individual households, and behavioral rules are encoded to simulate communication with other agents and adoption of decentralized technologies, using a model of the diffusion of innovation. The framework is applied for an illustrative case study to simulate water resources sustainability over a long-term planning horizon.

Investigation on the governance model and effect of medical schools merged with comprehensive universities in China.

PubMed

Bai, Ge; Luo, Li

2013-08-01

This investigation analyzes the management of medical schools merged with comprehensive universities through internet search and research review to reveal management model and effect of the merger. The conclusion is safely reached that governance models are divided into two different patterns: centralized management and decentralized management. Eight universities, representing the two models, were selected and evaluated comprehensively. Among them, the universities that carried out decentralized management have greater development after the merger based on a quality comparison concerning freshmen, faculty, teaching, and research between the two patterns. © 2013 Wiley Publishing Asia Pty Ltd and Chinese Cochrane Center, West China Hospital of Sichuan University.

Decentralized nursing education in Northern Norway: a basis for continuing education to meet competence needs in rural Arctic healthcare services

PubMed Central

Skaalvik, Mari Wolff; Gaski, Margrete; Norbye, Bente

2014-01-01

Background Ensuring a sufficient nursing workforce, with respect to both number and relevant professional competencies, is crucial in rural Arctic regions in Norway. This study examines the continuing education (CE) of nurses who graduated from a decentralized nursing programme between 1994 and 2011. Objective This study aims to measure the extent to which the decentralized nursing education (DNE) in question has served as a basis for CE that is adapted to current and future community health care service needs in rural Arctic regions in northern Norway. More specifically, the study aims to investigate the frequency and scope of CE courses among the graduates of a DNE, the choice of study model and the degree of employment with respect to the relevant CE. Design This study is a quantitative survey providing descriptive statistics. Results The primary finding in this study is that 56% of the participants had engaged in CE and that they were employed in positions related to their education. The majority of students with decentralized bachelor's degrees engaged in CE that was part time and/or decentralized. Conclusions More than half of the population in this study had completed CE despite no mandatory obligation in order to maintain licensure. Furthermore, 31% of the participants had completed more than one CE programme. The findings show that the participants preferred CE organized as part time and or decentralized studies. PMID:25279355

Decentralized-feedback pole placement of linear systems

NASA Technical Reports Server (NTRS)

Wang, X.; Martin, C. F.; Gilliam, D.; Byrnes, C. I.

1992-01-01

A projectile product spaces model is used to analyze decentralized systems. The degree of the pole placement map is computed. The conditions under which the degree is odd are also given. Twin lift systems are studied. It is proved that the poles of a twin lift system can be assigned to any values by local static and local dynamic feedback laws if and only if the system is jointly controllable.

A Framework for Information Theoretic Cooperative Sensing and Predictive Control

DTIC Science & Technology

2012-09-11

Miroslav Barić and Francesco Borelli , Decentralized Robust Control Invariance for a Network of Integrators, Proceeding of American Control...from http: //www.mpc.berkeley.edu. P4 Miroslav Barić and Francesco Borelli , Distributed Averaging with Flow Constraints, Proceeding of American Control

GVE-Based Dynamics and Control for Formation Flying Spacecraft

NASA Technical Reports Server (NTRS)

Breger, Louis; How, Jonathan P.

2004-01-01

Formation flying is an enabling technology for many future space missions. This paper presents extensions to the equations of relative motion expressed in Keplerian orbital elements, including new initialization techniques for general formation configurations. A new linear time-varying form of the equations of relative motion is developed from Gauss Variational Equations and used in a model predictive controller. The linearizing assumptions for these equations are shown to be consistent with typical formation flying scenarios. Several linear, convex initialization techniques are presented, as well as a general, decentralized method for coordinating a tetrahedral formation using differential orbital elements. Control methods are validated using a commercial numerical propagator.

Centralized vs. decentralized thermal IR inspection policy: experience from a major Brazilian electric power company

NASA Astrophysics Data System (ADS)

dos Santos, Laerte; da Costa Bortoni, Edson; Barbosa, Luiz C.; Araujo, Reyler A.

2005-03-01

Furnas Centrais Elétricas S.A is one of the greatest companies of the Brazilian electric power sector and a pioneer in using infrared thermography. In the early 70s, the maintenance policy used was a centralized approach, with only one inspection team to cover all the company"s facilities. In the early 90s, FURNAS decided to decentralize the thermography inspections creating several inspection teams. This new maintenance policy presented several advantages when compared to the previous one. However the credibility of the results obtained with the thermal inspection was frequently being questioned, in part due to the lack of a detailed planning to carry out the transition from the centralized inspection to the decentralized one. In some areas of the company it was suggested the inactivation of the thermography. This paper presents the experience of FURNAS with these different maintenance policies and details the procedures which have been taken that nowadays the infrared thermal inspection has become one of the most important techniques of predictive maintenance in the company.

Introducing local property tax for fiscal decentralization and local authority autonomy

NASA Astrophysics Data System (ADS)

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.

Issues concerning centralized versus decentralized power deployment

NASA Technical Reports Server (NTRS)

Metcalf, Kenneth J.; Harty, Richard B.; Robin, James F.

1991-01-01

The results of a study of proposed lunar base architectures to identify issues concerning centralized and decentralized power system deployment options are presented. The power system consists of the energy producing system (power plant), the power conditioning components used to convert the generated power into the form desired for transmission, the transmission lines that conduct this power from the power sources to the loads, and the primary power conditioning hardware located at the user end. Three power system architectures, centralized, hybrid, and decentralized, were evaluated during the course of this study. Candidate power sources were characterized with respect to mass and radiator area. Two electrical models were created for each architecture to identify the preferred method of power transmission, dc or ac. Each model allowed the transmission voltage level to be varied at assess the impact on power system mass. The ac power system models also permitted the transmission line configurations and placements to determine the best conductor construction and installation location. Key parameters used to evaluate each configuration were power source and power conditioning component efficiencies, masses, and radiator areas; transmission line masses and operating temperatures; and total system mass.

Decentralized control of large flexible structures by joint decoupling

NASA Technical Reports Server (NTRS)

Su, Tzu-Jeng; Juang, Jer-Nan

1992-01-01

A decentralized control design method is presented for large complex flexible structures by using the idea of joint decoupling. The derivation is based on a coupled substructure state-space model, which is obtained from enforcing conditions of interface compatibility and equilibrium to the substructure state-space models. It is shown that by restricting the control law to be localized state feedback and by setting the joint actuator input commands to decouple joint 'degrees of freedom' (dof) from interior dof, the global structure control design problem can be decomposed into several substructure control design problems. The substructure control gains and substructure observers are designed based on modified substructure state-space models. The controllers produced by the proposed method can operate successfully at the individual substructure level as well as at the global structure level. Therefore, not only control design but also control implementation is decentralized. Stability and performance requirement of the closed-loop system can be achieved by using any existing state feedback control design method. A two-component mass-spring damper system and a three-truss structure are used as examples to demonstrate the proposed method.

Low Decision Space Means No Decentralization in Fiji Comment on "Decentralisation of Health Services in Fiji: A Decision Space Analysis".

PubMed

Faguet, Jean-Paul

2016-06-22

Mohammed, North, and Ashton find that decentralization in Fiji shifted health-sector workloads from tertiary hospitals to peripheral health centres, but with little transfer of administrative authority from the centre. Decision-making in five functional areas analysed remains highly centralized. They surmise that the benefits of decentralization in terms of services and outcomes will be limited. This paper invokes Faguet's (2012) model of local government responsiveness and accountability to explain why this is so - not only for Fiji, but in any country that decentralizes workloads but not the decision space of local governments. A competitive dynamic between economic and civic actors that interact to generate an open, competitive politics, which in turn produces accountable, responsive government can only occur where real power and resources have been devolved to local governments. Where local decision space is lacking, by contrast, decentralization is bound to fail because it has not really happened in the first place. © 2016 The Author(s); Published by Kerman University of Medical Sciences. This is an open-access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

A Decentralized Adaptive Approach to Fault Tolerant Flight Control

NASA Technical Reports Server (NTRS)

Wu, N. Eva; Nikulin, Vladimir; Heimes, Felix; Shormin, Victor

2000-01-01

This paper briefly reports some results of our study on the application of a decentralized adaptive control approach to a 6 DOF nonlinear aircraft model. The simulation results showed the potential of using this approach to achieve fault tolerant control. Based on this observation and some analysis, the paper proposes a multiple channel adaptive control scheme that makes use of the functionally redundant actuating and sensing capabilities in the model, and explains how to implement the scheme to tolerate actuator and sensor failures. The conditions, under which the scheme is applicable, are stated in the paper.

Decentralization and the Composition of Public Expenditures

DTIC Science & Technology

2012-01-01

decentralized governance and expenditure composition by means of a distance-sensitive representative agent model. Then we estimate the impact of fiscal...countries with regards to population age structure. We are not certain of what effects that may have in our estimates , but previous studies have found find...variables to estimate a scalar value for g(xβ), which then is multiplied to each variables coefficient. For this, we choose the mean values of the

Experimenting with Decentralization: The Politics of Change.

ERIC Educational Resources Information Center

Wohlstetter, Priscilla

The relationship between the political context of school districts and their choices of decentralization policy is explored in this paper. It was expected that district politics would affect decentralization policies in two ways: the form of decentralization adopted and the degree of change. The decision to decentralize in three large urban school…

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

NASA Astrophysics Data System (ADS)

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.

Fuzzy Adaptive Decentralized Optimal Control for Strict Feedback Nonlinear Large-Scale Systems.

PubMed

Sun, Kangkang; Sui, Shuai; Tong, Shaocheng

2018-04-01

This paper considers the optimal decentralized fuzzy adaptive control design problem for a class of interconnected large-scale nonlinear systems in strict feedback form and with unknown nonlinear functions. The fuzzy logic systems are introduced to learn the unknown dynamics and cost functions, respectively, and a state estimator is developed. By applying the state estimator and the backstepping recursive design algorithm, a decentralized feedforward controller is established. By using the backstepping decentralized feedforward control scheme, the considered interconnected large-scale nonlinear system in strict feedback form is changed into an equivalent affine large-scale nonlinear system. Subsequently, an optimal decentralized fuzzy adaptive control scheme is constructed. The whole optimal decentralized fuzzy adaptive controller is composed of a decentralized feedforward control and an optimal decentralized control. It is proved that the developed optimal decentralized controller can ensure that all the variables of the control system are uniformly ultimately bounded, and the cost functions are the smallest. Two simulation examples are provided to illustrate the validity of the developed optimal decentralized fuzzy adaptive control scheme.

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

NASA Astrophysics Data System (ADS)

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

2018-02-01

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

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

PubMed

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

2010-01-01

Evidence-based findings of the effects of nursing station design on nurses' work environment and work behavior are essential to improve conditions and increase retention among these fundamental members of the healthcare delivery team. The purpose of this exploratory study was to investigate how nursing station design (i.e., centralized and decentralized nursing station layouts) affected nurses' use of space, patient visibility, noise levels, and perceptions of the work environment. Advances in information technology have enabled nurses to move away from traditional centralized paper-charting stations to smaller decentralized work stations and charting substations located closer to, or inside of, patient rooms. Improved understanding of the trade-offs presented by centralized and decentralized nursing station design has the potential to provide useful information for future nursing station layouts. This information will be critical for understanding the nurse environment "fit." The study used an exploratory design with both qualitative and quantitative methods. Qualitative data regarding the effects of nursing station design on nurses' health and work environment were gathered by means of focus group interviews. Quantitative data-gathering techniques included place- and person-centered space use observations, patient visibility assessments, sound level measurements, and an online questionnaire regarding perceptions of the work environment. Nurses on all units were observed most frequently performing telephone, computer, and administrative duties. Time spent using telephones, computers, and performing other administrative duties was significantly higher in the centralized nursing stations. Consultations with medical staff and social interactions were significantly less frequent in decentralized nursing stations. There were no indications that either centralized or decentralized nursing station designs resulted in superior visibility. Sound levels measured in all 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.

Cross-sectoral optimization and visualization of transformation processes in urban water infrastructures in rural areas.

PubMed

Baron, S; Kaufmann Alves, I; Schmitt, T G; Schöffel, S; Schwank, J

2015-01-01

Predicted demographic, climatic and socio-economic changes will require adaptations of existing water supply and wastewater disposal systems. Especially in rural areas, these new challenges will affect the functionality of the present systems. This paper presents a joint interdisciplinary research project with the objective of developing an innovative software-based optimization and decision support system for the implementation of long-term transformations of existing infrastructures of water supply, wastewater and energy. The concept of the decision support and optimization tool is described and visualization methods for the presentation of results are illustrated. The model is tested in a rural case study region in the Southwest of Germany. A transformation strategy for a decentralized wastewater treatment concept and its visualization are presented for a model village.

Natural Resource Dependency and Decentralized Conservation Within Kanchenjunga Conservation Area Project, Nepal

NASA Astrophysics Data System (ADS)

Parker, Pete; Thapa, Brijesh

2012-02-01

Kanchenjunga Conservation Area Project (KCAP) in Nepal is among the first protected areas in the world to institute a completely decentralized system of conservation and development. Proponents of decentralized conservation claim that it increases management efficiency, enhances the responsiveness to local needs, and promotes greater equity among local residents. This study assessed local equity by evaluating the levels of dependencies on natural resources among households and the factors affecting that dependency. Data were collected via detailed surveys among 205 randomly selected households within the KCAP. Natural resource dependency was evaluated by comparing the ratio of total household income to income derived from access to natural resources. Economic, social, and access-related variables were employed to determine potential significant predictors of dependency. Overall, households were heavily dependent on natural resources for their income, especially households at higher elevations and those with more adult members. The households that received remittances were most able to supplement their income and, therefore, drastically reduced their reliance on the access to natural resources. Socio-economic variables, such as land holdings, education, caste, and ethnicity, failed to predict dependency. Household participation in KCAP-sponsored training programs also failed to affect household dependency; however, fewer than 20% of the households had any form of direct contact with KCAP personnel within the past year. The success of the KCAP as a decentralized conservation program is contingent on project capacity-building via social mobilization, training programs, and participatory inclusion in decision making to help alleviate the dependency on natural resources.

Natural resource dependency and decentralized conservation within Kanchenjunga Conservation Area Project, Nepal.

PubMed

Parker, Pete; Thapa, Brijesh

2012-02-01

Kanchenjunga Conservation Area Project (KCAP) in Nepal is among the first protected areas in the world to institute a completely decentralized system of conservation and development. Proponents of decentralized conservation claim that it increases management efficiency, enhances the responsiveness to local needs, and promotes greater equity among local residents. This study assessed local equity by evaluating the levels of dependencies on natural resources among households and the factors affecting that dependency. Data were collected via detailed surveys among 205 randomly selected households within the KCAP. Natural resource dependency was evaluated by comparing the ratio of total household income to income derived from access to natural resources. Economic, social, and access-related variables were employed to determine potential significant predictors of dependency. Overall, households were heavily dependent on natural resources for their income, especially households at higher elevations and those with more adult members. The households that received remittances were most able to supplement their income and, therefore, drastically reduced their reliance on the access to natural resources. Socio-economic variables, such as land holdings, education, caste, and ethnicity, failed to predict dependency. Household participation in KCAP-sponsored training programs also failed to affect household dependency; however, fewer than 20% of the households had any form of direct contact with KCAP personnel within the past year. The success of the KCAP as a decentralized conservation program is contingent on project capacity-building via social mobilization, training programs, and participatory inclusion in decision making to help alleviate the dependency on natural resources.

Decentralized safety concept for closed-loop controlled intensive care.

PubMed

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.

Robust Decentralized Nonlinear Control for a Twin Rotor MIMO System

PubMed Central

Belmonte, Lidia María; Morales, Rafael; Fernández-Caballero, Antonio; Somolinos, José Andrés

2016-01-01

This article presents the design of a novel decentralized nonlinear multivariate control scheme for an underactuated, nonlinear and multivariate laboratory helicopter denominated the twin rotor MIMO system (TRMS). The TRMS is characterized by a coupling effect between rotor dynamics and the body of the model, which is due to the action-reaction principle originated in the acceleration and deceleration of the motor-propeller groups. The proposed controller is composed of two nested loops that are utilized to achieve stabilization and precise trajectory tracking tasks for the controlled position of the generalized coordinates of the TRMS. The nonlinear internal loop is used to control the electrical dynamics of the platform, and the nonlinear external loop allows the platform to be perfectly stabilized and positioned in space. Finally, we illustrate the theoretical control developments with a set of experiments in order to verify the effectiveness of the proposed nonlinear decentralized feedback controller, in which a comparative study with other controllers is performed, illustrating the excellent performance of the proposed robust decentralized control scheme in both stabilization and trajectory tracking tasks. PMID:27472338

Robust Decentralized Nonlinear Control for a Twin Rotor MIMO System.

PubMed

Belmonte, Lidia María; Morales, Rafael; Fernández-Caballero, Antonio; Somolinos, José Andrés

2016-07-27

This article presents the design of a novel decentralized nonlinear multivariate control scheme for an underactuated, nonlinear and multivariate laboratory helicopter denominated the twin rotor MIMO system (TRMS). The TRMS is characterized by a coupling effect between rotor dynamics and the body of the model, which is due to the action-reaction principle originated in the acceleration and deceleration of the motor-propeller groups. The proposed controller is composed of two nested loops that are utilized to achieve stabilization and precise trajectory tracking tasks for the controlled position of the generalized coordinates of the TRMS. The nonlinear internal loop is used to control the electrical dynamics of the platform, and the nonlinear external loop allows the platform to be perfectly stabilized and positioned in space. Finally, we illustrate the theoretical control developments with a set of experiments in order to verify the effectiveness of the proposed nonlinear decentralized feedback controller, in which a comparative study with other controllers is performed, illustrating the excellent performance of the proposed robust decentralized control scheme in both stabilization and trajectory tracking tasks.

Optical zone centration: a retrospective analysis of the excimer laser after three years

NASA Astrophysics Data System (ADS)

Vervecken, Filip; Trau, Rene; Mertens, Erik L.; Vanhorenbeeck, R.; Van Aerde, F.; Zen, J.; Haustrate, F.; Tassignon, Marie J.

1996-12-01

The aim of this study was to evaluate the implication of the mechanical factor 'decentration' on the visual outcome after PRK. 100 eyes of 70 patients were included. The mean decentration was 0.27 mm +/- 0.18. Decentration was less than 0.5 mm in 84 percent of the cases. The importance of the decentration was investigated by the statistical correlation of decentration from the pupilcenter and the visual outcome. We did not find any statistical significant association for decentrations less than 1 mm. Our conclusion is that decentration, if less than 1 mm, does not play an important role in the final visual outcome after PRK.

The role of governance in implementing task-shifting from physicians to nurses in advanced roles in Europe, U.S., Canada, New Zealand and Australia.

PubMed

Maier, Claudia B

2015-12-01

Task-shifting from physicians to nurses is increasing worldwide; however, research on how it is governed is scarce. This international study assessed task-shifting governance models and implications on practice, based on a literature scoping review; and a survey with 93 country experts in 39 countries (response rate: 85.3%). Governance was assessed by several indicators, regulation of titles, scope of practice, prescriptive authority, and registration policies. This policy analysis focused on eleven countries with task-shifting at the Advanced Practice Nursing/Nurse Practitioner (APN/NP) level. Governance models ranged from national, decentralized to no regulation, but at the discretion of employers and settings. In countries with national or decentralized regulation, restrictive scope of practice laws were shown as barrier, up-to-date laws as enablers to advanced practice. Countries with decentralized regulation resulted in uneven levels of practice. In countries leaving governance to individual settings, practice variations existed, moreover data availability and role clarity was limited. Policy options include periodic reviews to ensure laws are up to date, minimum harmonization in decentralized contexts, harmonized educational and practice-level requirements to reduce practice variation and ensure quality. From a European Union (EU) perspective, regulation is preferred over non-regulation as a first step toward the recognition of qualifications in countries with similar levels of advanced practice. Countries early on in the process need to be aware that different governance models can influence practice. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Human resources for health and decentralization policy in the Brazilian health system

PubMed Central

2011-01-01

Background The Brazilian health reform process, following the establishment of the Unified Health System (SUS), has had a strong emphasis on decentralization, with a special focus on financing, management and inter-managerial agreements. Brazil is a federal country and the Ministry of Health (MoH), through the Secretary of Labour Management and Health Education, is responsible for establishing national policy guidelines for health labour management, and also for implementing strategies for the decentralization of management of labour and education in the federal states. This paper assesses whether the process of decentralizing human resources for health (HRH) management and organization to the level of the state and municipal health departments has involved investments in technical, political and financial resources at the national level. Methods The research methods used comprise a survey of HRH managers of states and major municipalities (including capitals) and focus groups with these HRH managers - all by geographic region. The results were obtained by combining survey and focus group data, and also through triangulation with the results of previous research. Results The results of this evaluation showed the evolution policy, previously restricted to the field of 'personnel administration', now expanded to a conceptual model for health labour management and education-- identifying progress, setbacks, critical issues and challenges for the consolidation of the decentralized model for HRH management. The results showed that 76.3% of the health departments have an HRH unit. It was observed that 63.2% have an HRH information system. However, in most health departments, the HRH unit uses only the payroll and administrative records as data sources. Concerning education in health, 67.6% of the HRH managers mentioned existing cooperation with educational and teaching institutions for training and/or specialization of health workers. Among them, specialization courses account for 61.4% and short courses for 56.1%. Conclusions Due to decentralization, the HRH area has been restructured and policies beyond traditional administrative activities have been developed. However, twenty years on from the establishment of the SUS, there remains a low level of institutionalization in the HRH area, despite recent efforts of the MoH. PMID:21586156

Is the rotation of the femoral head a potential initiation for cutting out? A theoretical and experimental approach.

PubMed

Lenich, Andreas; Bachmeier, Samuel; Prantl, Lukas; Nerlich, Michael; Hammer, Jochen; Mayr, Edgar; Al-Munajjed, Amir Andreas; Füchtmeier, Bernd

2011-04-22

Since cut-out still remains one of the major clinical challenges in the field of osteoporotic proximal femur fractures, remarkable developments have been made in improving treatment concepts. However, the mechanics of these complications have not been fully understood.We hypothesize using the experimental data and a theoretical model that a previous rotation of the femoral head due to de-central implant positioning can initiate a cut-out. In this investigation we analysed our experimental data using two common screws (DHS/Gamma 3) and helical blades (PFN A/TFN) for the fixation of femur fractures in a simple theoretical model applying typical gait pattern on de-central positioned implants. In previous tests during a forced implant rotation by a biomechanical testing machine in a human femoral head the two screws showed failure symptoms (2-6Nm) at the same magnitude as torques acting in the hip during daily activities with de-central implant positioning, while the helical blades showed a better stability (10-20Nm).To calculate the torque of the head around the implant only the force and the leverarm is needed (N [Nm] = F [N] * × [m]). The force F is a product of the mass M [kg] multiplied by the acceleration g [m/s2]. The leverarm is the distance between the center of the head of femur and the implant center on a horizontal line. Using 50% of 75 kg body weight a torque of 0.37Nm for the 1 mm decentralized position and 1.1Nm for the 3 mm decentralized position of the implant was calculated. At 250% BW, appropriate to a normal step, torques of 1.8Nm (1 mm) and 5.5Nm (3 mm) have been calculated.Comparing of the experimental and theoretical results shows that both screws fail in the same magnitude as torques occur in a more than 3 mm de-central positioned implant. We conclude the center-center position in the head of femur of any kind of lag screw or blade is to be achieved to minimize rotation of the femoral head and to prevent further mechanical complications.

Human resources for health and decentralization policy in the Brazilian health system.

PubMed

Pierantoni, Celia Regina; Garcia, Ana Claudia P

2011-05-17

The Brazilian health reform process, following the establishment of the Unified Health System (SUS), has had a strong emphasis on decentralization, with a special focus on financing, management and inter-managerial agreements. Brazil is a federal country and the Ministry of Health (MoH), through the Secretary of Labour Management and Health Education, is responsible for establishing national policy guidelines for health labour management, and also for implementing strategies for the decentralization of management of labour and education in the federal states. This paper assesses whether the process of decentralizing human resources for health (HRH) management and organization to the level of the state and municipal health departments has involved investments in technical, political and financial resources at the national level. The research methods used comprise a survey of HRH managers of states and major municipalities (including capitals) and focus groups with these HRH managers - all by geographic region. The results were obtained by combining survey and focus group data, and also through triangulation with the results of previous research. The results of this evaluation showed the evolution policy, previously restricted to the field of 'personnel administration', now expanded to a conceptual model for health labour management and education-- identifying progress, setbacks, critical issues and challenges for the consolidation of the decentralized model for HRH management. The results showed that 76.3% of the health departments have an HRH unit. It was observed that 63.2% have an HRH information system. However, in most health departments, the HRH unit uses only the payroll and administrative records as data sources. Concerning education in health, 67.6% of the HRH managers mentioned existing cooperation with educational and teaching institutions for training and/or specialization of health workers. Among them, specialization courses account for 61.4% and short courses for 56.1%. Due to decentralization, the HRH area has been restructured and policies beyond traditional administrative activities have been developed. However, twenty years on from the establishment of the SUS, there remains a low level of institutionalization in the HRH area, despite recent efforts of the MoH.

Two-echelon logistics service supply chain decision game considering quality supervision

NASA Astrophysics Data System (ADS)

Shi, Jiaying

2017-10-01

Due to the increasing importance of supply chain logistics service, we established the Stackelberg game model between single integrator and single subcontractors under decentralized and centralized circumstances, and found that logistics services integrators as a leader prefer centralized decision-making but logistics service subcontractors tend to the decentralized decision-making. Then, we further analyzed why subcontractor chose to deceive and rebuilt a principal-agent game model to monitor the logistics services quality of them. Mixed Strategy Nash equilibrium and related parameters were discussed. The results show that strengthening the supervision and coordination can improve the quality level of logistics service supply chain.

A cooperative game theory approach to transmission planning in power systems

NASA Astrophysics Data System (ADS)

Contreras, Javier

The rapid restructuring of the electric power industry from a vertically integrated entity into a decentralized industry has given rise to complex problems. In particular, the transmission component of the electric power system requires new methodologies to fully capture this emerging competitive industry. Game theory models are used to model strategic interactions in a competitive environment. This thesis presents a new decentralized framework to study the transmission network expansion problem using cooperative game theory. First, the players and the rules of the game are defined. Second, a coalition formation scheme is developed. Finally, the optimized cost of expansion is allocated based on the history of the coalition formation.

Cost-benefit evaluation of a decentralized water system for wastewater reuse and environmental protection.

PubMed

Chen, R; Wang, X C

2009-01-01

This paper proposed a net benefit value (NBV) model for cost-benefit evaluation of wastewater treatment and reuse projects, and attention was mainly paid to decentralized systems which are drawing wide interests all over the world especially in the water-deficient countries and regions. In the NBV model, all the factors related to project costs are monetary ones which can be calculated by using traditional methods, while many of the factors related to project benefits are non-monetary ones which need sophisticated methods for monetization. In this regard, the authors elaborated several methods for monetization of the benefits from wastewater discharge reduction, local environment improvement, and human health protection. The proposed model and methods were applied for the cost-benefit evaluation of a decentralized water reclamation and reuse project in a newly developed residential area in Xi'an, China. The system with dual-pipe collection and grey water treatment and reuse was found to be economically ineligible (NBV > 0) when all the treated water is reused for artificial pond replenishment, gardening and other non-potable purposes by taking into account the benefit of water saving. As environmental benefits are further considered, the economic advantage of the project is more significant.

Balancing Officer Community Manpower through Decentralization: Granular Programming Revisited (1REV)

DTIC Science & Technology

2017-08-01

supply-demand imbalances Economic theory identifies costs and benefits associated with decentralization. On the benefits side, decentralized decision...patterns rather than costs . Granular programming as a decentralized, market-based initiative The costs and benefits of decentralized (instead of...paygrade-specific rates were based on average MPN costs by paygrade. The benefits of this approach to granular programming are that it is conceptually

Ophiuroid robot that self-organizes periodic and non-periodic arm movements.

PubMed

Kano, Takeshi; Suzuki, Shota; Watanabe, Wataru; Ishiguro, Akio

2012-09-01

Autonomous decentralized control is a key concept for understanding the mechanism underlying adaptive and versatile locomotion of animals. Although the design of an autonomous decentralized control system that ensures adaptability by using coupled oscillators has been proposed previously, it cannot comprehensively reproduce the versatility of animal behaviour. To tackle this problem, we focus on using ophiuroids as a simple model that exhibits versatile locomotion including periodic and non-periodic arm movements. Our existing model for ophiuroid locomotion uses an active rotator model that describes both oscillatory and excitatory properties. In this communication, we develop an ophiuroid robot to confirm the validity of this proposed model in the real world. We show that the robot travels by successfully coordinating periodic and non-periodic arm movements in response to external stimuli.

Decentralization and primary health care: some negative implications in developing countries.

PubMed

Collins, C; Green, A

1994-01-01

Decentralization is a highly popular concept, being a key element of Primary Health Care policies. There are, however, certain negative implications of decentralization that must be taken into account. These are analyzed in this article with particular reference to developing countries. The authors criticize the tendency for decentralization to be associated with state limitations, and discuss the dilemma of relating decentralization, which is the enhancement of the different, to equity, which is the promotion of equivalence. Those situations in which decentralization can strengthen political domination are described. The authors conclude by setting out a checklist of warning questions and issues to be taken into account to ensure that decentralization genuinely facilitates the Primary Health Care orientation of health policy.

What supervisors want to know about decentralization.

PubMed

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.

Decentralized adaptive control

NASA Technical Reports Server (NTRS)

Oh, B. J.; Jamshidi, M.; Seraji, H.

1988-01-01

A decentralized adaptive control is proposed to stabilize and track the nonlinear, interconnected subsystems with unknown parameters. The adaptation of the controller gain is derived by using model reference adaptive control theory based on Lyapunov's direct method. The adaptive gains consist of sigma, proportional, and integral combination of the measured and reference values of the corresponding subsystem. The proposed control is applied to the joint control of a two-link robot manipulator, and the performance in computer simulation corresponds with what is expected in theoretical development.

Does HIV services decentralization protect against the risk of catastrophic health expenditures?: some lessons from Cameroon.

PubMed

Boyer, Sylvie; Abu-Zaineh, Mohammad; Blanche, Jérôme; Loubière, Sandrine; Bonono, Renée-Cécile; Moatti, Jean-Paul; Ventelou, Bruno

2011-12-01

Scaling up antiretroviral treatment (ART) through decentralization of HIV care is increasingly recommended as a strategy toward ensuring equitable access to treatment. However, there have been hitherto few attempts to empirically examine the performance of this policy, and particularly its role in protecting against the risk of catastrophic health expenditures (CHE). This article therefore seeks to assess whether HIV care decentralization has a protective effect against the risk of CHE associated with HIV infection. DATA SOURCE AND STUDY DESIGN: We use primary data from the cross-sectional EVAL-ANRS 12-116 survey, conducted in 2006-2007 among a random sample of 3,151 HIV-infected outpatients followed up in 27 hospitals in Cameroon. DATA COLLECTION AND METHODS: Data collected contain sociodemographic, economic, and clinical information on patients as well as health care supply-related characteristics. We assess the determinants of CHE among the ART-treated patients using a hierarchical logistic model (n = 2,412), designed to adequately investigate the separate effects of patients and supply-related characteristics. Expenditures for HIV care exceed 17 percent of household income for 50 percent of the study population. After adjusting for individual characteristics and technological level, decentralization of HIV services emerges as the main health system factor explaining interclass variance, with a protective effect on the risk of CHE. The findings suggest that HIV care decentralization is likely to enhance equity in access to ART. Decentralization appears, however, to be a necessary but insufficient condition to fully remove the risk of CHE, unless other innovative reforms in health financing are introduced. © Health Research and Educational Trust.

Scenario planning.

PubMed

Enzmann, Dieter R; Beauchamp, Norman J; Norbash, Alexander

2011-03-01

In facing future developments in health care, scenario planning offers a complementary approach to traditional strategic planning. Whereas traditional strategic planning typically consists of predicting the future at a single point on a chosen time horizon and mapping the preferred plans to address such a future, scenario planning creates stories about multiple likely potential futures on a given time horizon and maps the preferred plans to address the multiple described potential futures. Each scenario is purposefully different and specifically not a consensus worst-case, average, or best-case forecast; nor is scenario planning a process in probabilistic prediction. Scenario planning focuses on high-impact, uncertain driving forces that in the authors' example affect the field of radiology. Uncertainty is the key concept as these forces are mapped onto axes of uncertainty, the poles of which have opposed effects on radiology. One chosen axis was "market focus," with poles of centralized health care (government control) vs a decentralized private market. Another axis was "radiology's business model," with one pole being a unified, single specialty vs a splintered, disaggregated subspecialty. The third axis was "technology and science," with one pole representing technology enabling to radiology vs technology threatening to radiology. Selected poles of these axes were then combined to create 3 scenarios. One scenario, termed "entrepreneurialism," consisted of a decentralized private market, a disaggregated business model, and threatening technology and science. A second scenario, termed "socialized medicine," had a centralized market focus, a unified specialty business model, and enabling technology and science. A third scenario, termed "freefall," had a centralized market focus, a disaggregated business model, and threatening technology and science. These scenarios provide a range of futures that ultimately allow the identification of defined "signposts" that can suggest which basic features among the "possible futures" are playing out. Scenario planning provides for the implementation of appropriate constructed strategic responses. Scenarios allow for a pre-prepared game plan available for ready use as the future unfolds. They allow a deliberative response rather than a hastily constructed, urgent response. Copyright © 2011 American College of Radiology. Published by Elsevier Inc. All rights reserved.

A distributed finite-element modeling and control approach for large flexible structures

NASA Technical Reports Server (NTRS)

Young, K. D.

1989-01-01

An unconventional framework is described for the design of decentralized controllers for large flexible structures. In contrast to conventional control system design practice which begins with a model of the open loop plant, the controlled plant is assembled from controlled components in which the modeling phase and the control design phase are integrated at the component level. The developed framework is called controlled component synthesis (CCS) to reflect that it is motivated by the well developed Component Mode Synthesis (CMS) methods which were demonstrated to be effective for solving large complex structural analysis problems for almost three decades. The design philosophy behind CCS is also closely related to that of the subsystem decomposition approach in decentralized control.

Examination of sludge accumulation rates and sludge characteristics for a decentralized community wastewater treatment systems with individual primary clarifier tanks located in Wardsville (Ontario, Canada).

PubMed

Lossing, Heather; Champagne, Pascale; McLellan, P James

2010-01-01

In conventional septic systems, settling and partial treatment via anaerobic digestion occurs in the septic tank. One of the byproducts of solids separation in the septic tank is a semi-liquid material known as septage, which must be periodically pumped out. Septage includes the liquid portion within the tank, as well as the sludge that settles at the bottom of the tank and the scum that floats to the surface of the liquid layer. A number of factors can influence septage characteristics, as well as the sludge and scum accumulation rates within the tank. This paper presents the results of a 2007 field sampling study conducted in Wardsville (Ontario, Canada). The field study examined 29 individual residential two-chamber septic tanks in a community serviced by a decentralized wastewater treatment system in operation for approximately 7 years without septage removal. The field investigation provided a comprehensive data set that allowed for statistical analysis of the data to assess the more critical factors influencing solids accumulation rates within each of the clarifier chambers. With this data, a number of predictive models were developed using water usage data for each residence as an explanatory variable.

Patient Experiences of Decentralized HIV Treatment and Care in Plateau State, North Central Nigeria: A Qualitative Study

PubMed Central

Kolawole, Grace O.; Gilbert, Hannah N.; Dadem, Nancin Y.; Genberg, Becky L.; Agbaji, Oche O.

2017-01-01

Background. Decentralization of care and treatment for HIV infection in Africa makes services available in local health facilities. Decentralization has been associated with improved retention and comparable or superior treatment outcomes, but patient experiences are not well understood. Methods. We conducted a qualitative study of patient experiences in decentralized HIV care in Plateau State, north central Nigeria. Five decentralized care sites in the Plateau State Decentralization Initiative were purposefully selected. Ninety-three patients and 16 providers at these sites participated in individual interviews and focus groups. Data collection activities were audio-recorded and transcribed. Transcripts were inductively content analyzed to derive descriptive categories representing patient experiences of decentralized care. Results. Patient participants in this study experienced the transition to decentralized care as a series of “trade-offs.” Advantages cited included saving time and money on travel to clinic visits, avoiding dangers on the road, and the “family-like atmosphere” found in some decentralized clinics. Disadvantages were loss of access to ancillary services, reduced opportunities for interaction with providers, and increased risk of disclosure. Participants preferred decentralized services overall. Conclusion. Difficulty and cost of travel remain a fundamental barrier to accessing HIV care outside urban centers, suggesting increased availability of community-based services will be enthusiastically received. PMID:28331636

Patient Experiences of Decentralized HIV Treatment and Care in Plateau State, North Central Nigeria: A Qualitative Study.

PubMed

Kolawole, Grace O; Gilbert, Hannah N; Dadem, Nancin Y; Genberg, Becky L; Agaba, Patricia A; Okonkwo, Prosper; Agbaji, Oche O; Ware, Norma C

2017-01-01

Background. Decentralization of care and treatment for HIV infection in Africa makes services available in local health facilities. Decentralization has been associated with improved retention and comparable or superior treatment outcomes, but patient experiences are not well understood. Methods. We conducted a qualitative study of patient experiences in decentralized HIV care in Plateau State, north central Nigeria. Five decentralized care sites in the Plateau State Decentralization Initiative were purposefully selected. Ninety-three patients and 16 providers at these sites participated in individual interviews and focus groups. Data collection activities were audio-recorded and transcribed. Transcripts were inductively content analyzed to derive descriptive categories representing patient experiences of decentralized care. Results. Patient participants in this study experienced the transition to decentralized care as a series of "trade-offs." Advantages cited included saving time and money on travel to clinic visits, avoiding dangers on the road, and the "family-like atmosphere" found in some decentralized clinics. Disadvantages were loss of access to ancillary services, reduced opportunities for interaction with providers, and increased risk of disclosure. Participants preferred decentralized services overall. Conclusion. Difficulty and cost of travel remain a fundamental barrier to accessing HIV care outside urban centers, suggesting increased availability of community-based services will be enthusiastically received.

Breast cancer screening services: trade-offs in quality, capacity, outreach, and centralization.

PubMed

Güneş, Evrim D; Chick, Stephen E; Akşin, O Zeynep

2004-11-01

This work combines and extends previous work on breast cancer screening models by explicitly incorporating, for the first time, aspects of the dynamics of health care states, program outreach, and the screening volume-quality relationship in a service system model to examine the effect of public health policy and service capacity decisions on public health outcomes. We consider the impact of increasing standards for minimum reading volume to improve quality, expanding outreach with or without decentralization of service facilities, and the potential of queueing due to stochastic effects and limited capacity. The results indicate a strong relation between screening quality and the cost of screening and treatment, and emphasize the importance of accounting for service dynamics when assessing the performance of health care interventions. For breast cancer screening, increasing outreach without improving quality and maintaining capacity results in less benefit than predicted by standard models.

Using ontologies to model human navigation behavior in information networks: A study based on Wikipedia.

PubMed

Lamprecht, Daniel; Strohmaier, Markus; Helic, Denis; Nyulas, Csongor; Tudorache, Tania; Noy, Natalya F; Musen, Mark A

The need to examine the behavior of different user groups is a fundamental requirement when building information systems. In this paper, we present Ontology-based Decentralized Search (OBDS), a novel method to model the navigation behavior of users equipped with different types of background knowledge. Ontology-based Decentralized Search combines decentralized search, an established method for navigation in social networks, and ontologies to model navigation behavior in information networks. The method uses ontologies as an explicit representation of background knowledge to inform the navigation process and guide it towards navigation targets. By using different ontologies, users equipped with different types of background knowledge can be represented. We demonstrate our method using four biomedical ontologies and their associated Wikipedia articles. We compare our simulation results with base line approaches and with results obtained from a user study. We find that our method produces click paths that have properties similar to those originating from human navigators. The results suggest that our method can be used to model human navigation behavior in systems that are based on information networks, such as Wikipedia. This paper makes the following contributions: (i) To the best of our knowledge, this is the first work to demonstrate the utility of ontologies in modeling human navigation and (ii) it yields new insights and understanding about the mechanisms of human navigation in information networks.

Using ontologies to model human navigation behavior in information networks: A study based on Wikipedia

PubMed Central

Lamprecht, Daniel; Strohmaier, Markus; Helic, Denis; Nyulas, Csongor; Tudorache, Tania; Noy, Natalya F.; Musen, Mark A.

2015-01-01

The need to examine the behavior of different user groups is a fundamental requirement when building information systems. In this paper, we present Ontology-based Decentralized Search (OBDS), a novel method to model the navigation behavior of users equipped with different types of background knowledge. Ontology-based Decentralized Search combines decentralized search, an established method for navigation in social networks, and ontologies to model navigation behavior in information networks. The method uses ontologies as an explicit representation of background knowledge to inform the navigation process and guide it towards navigation targets. By using different ontologies, users equipped with different types of background knowledge can be represented. We demonstrate our method using four biomedical ontologies and their associated Wikipedia articles. We compare our simulation results with base line approaches and with results obtained from a user study. We find that our method produces click paths that have properties similar to those originating from human navigators. The results suggest that our method can be used to model human navigation behavior in systems that are based on information networks, such as Wikipedia. This paper makes the following contributions: (i) To the best of our knowledge, this is the first work to demonstrate the utility of ontologies in modeling human navigation and (ii) it yields new insights and understanding about the mechanisms of human navigation in information networks. PMID:26568745

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

PubMed

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.

Modeling Land Use Change in the Chesapeake Bay Watershed

NASA Astrophysics Data System (ADS)

Claire, J. A.; Goetz, S. J.; Bockstael, N.

2003-12-01

Low density, decentralized residential and commercial development is increasingly the dominant pattern of exurban land use in many developed countries, particularly the United States. The term "sprawl" is now commonly used to describe this form of development, the environmental and quality-of-life impacts of which are becoming central to debates over land use in urban and suburban areas. Continued poor health of the Chesapeake Bay, located in the Mid-Atlantic region of the United States, is due in part to disruptions in the hydrological system caused by urban and suburban development throughout the 167,000 square kilometer watershed. We present results of a spatial predictive model of land use change based on cellular automata (SLEUTH), which was calibrated using high resolution (30m cell size) maps of the built environment derived from Landsat ETM+ imagery for the period 1986-2000. The model was applied to a 23,740 square kilometer area centered on Washington DC - Baltimore MD, and predictions were made out to 2030 assuming three different policy scenarios (current trends, managed growth, and "sustainable"). Accuracy of the model was assessed at three scales (pixel, watershed and county) and overall strengths and weaknesses of the model are presented, particularly in comparison to other econometric modeling approaches.

Back to basics: does decentralization improve health system performance? Evidence from Ceara in north-east Brazil.

PubMed Central

Atkinson, Sarah; Haran, Dave

2004-01-01

OBJECTIVE: To examine whether decentralization has improved health system performance in the State of Ceara, north-east Brazil. METHODS: Ceara is strongly committed to decentralization. A survey across 45 local (municipio) health systems collected data on performance and formal organization, including decentralization, informal management and local political culture. The indicators for informal management and local political culture were based on prior ethnographic research. Data were analysed using analysis of variance, Duncan's post-hoc test and multiple regression. FINDINGS: Decentralization was associated with improved performance, but only for 5 of our 22 performance indicators. Moreover, in the multiple regression, decentralization explained the variance in only one performance indicator; indicators for informal management and political culture appeared to be more important influences. However, some indicators for informal management were themselves associated with decentralization but not any of the political culture indicators. CONCLUSION: Good management practices in the study led to decentralized local health systems rather than vice versa. Any apparent association between decentralization and performance seems to be an artefact of the informal management, and the wider political culture in which a local health system is embedded strongly influences the performance of local health systems. PMID:15640917

Comparative Perspectives on Educational Decentralization: An Exercise in Contradiction?

ERIC Educational Resources Information Center

Weiler, Hans N.

1990-01-01

It is argued that policies decentralizing the governance of educational systems, although appealing in the abstract, tend to be fundamentally ambivalent and in conflict with powerful forces favoring centralization. Tensions surrounding the issue of decentralization are discussed, with emphasis on the relationship between decentralization and…

Does Decentralization Improve Health System Performance and Outcomes in Low- and Middle-Income Countries? A Systematic Review of Evidence From Quantitative Studies.

PubMed

Dwicaksono, Adenantera; Fox, Ashley M

2018-06-01

Policy Points: For more than 3 decades, international development agencies have advocated health system decentralization to improve health system performance in low- and middle-income countries. We found little rigorous evidence documenting the impact of decentralization processes on health system performance or outcomes in part due to challenges in measuring such far-reaching and multifaceted system-level changes. We propose a renewed research agenda that focuses on discrete definitions of decentralization and how institutional factors and mechanisms affect health system performance and outcomes within the general context of decentralized governance structures. Despite the widespread adoption of decentralization reforms as a means to improve public service delivery in developing countries since the 1980s, empirical evidence of the role of decentralization on health system improvement is still limited and inconclusive. This study reviewed studies published from 2000 to 2016 with adequate research designs to identify evidence on whether and how decentralization processes have impacted health systems. We conducted a systematic review of peer-reviewed journal articles from the public health and social science literature. We searched for articles within 9 databases using predefined search terms reflecting decentralization and health system constructs. Inclusion criteria were original research articles, low- and middle-income country settings, quantifiable outcome measures, and study designs that use comparisons or statistical adjustments. We excluded studies in high-income country settings and/or published in a non-English language. Sixteen studies met our prespecified inclusion and exclusion criteria and were grouped based on outcomes measured: health system inputs (n = 3), performance (n = 7), and health outcomes (n = 7). Numerous studies addressing conceptual issues related to decentralization but without any attempt at empirical estimation were excluded. Overall, we found mixed results regarding the effects of decentralization on health system indicators with seemingly beneficial effects on health system performance and health outcomes. Only 10 studies were considered to have relatively low risks of bias. This study reveals the limited empirical knowledge of the impact of decentralization on health system performance. Mixed empirical findings on the role of decentralization on health system performance and outcomes highlight the complexity of decentralization processes and their systemwide effects. Thus, we propose a renewed research agenda that focuses on discrete definitions of decentralization and how institutional factors and mechanisms affect health system performance and outcomes within the general context of decentralized governance structures. © 2018 Milbank Memorial Fund.

Theory and applications survey of decentralized control methods

NASA Technical Reports Server (NTRS)

Athans, M.

1975-01-01

A nonmathematical overview is presented of trends in the general area of decentralized control strategies which are suitable for hierarchical systems. Advances in decentralized system theory are closely related to advances in the so-called stochastic control problem with nonclassical information pattern. The basic assumptions and mathematical tools pertaining to the classical stochastic control problem are outlined. Particular attention is devoted to pitfalls in the mathematical problem formulation for decentralized control. Major conclusions are that any purely deterministic approach to multilevel hierarchical dynamic systems is unlikely to lead to realistic theories or designs, that the flow of measurements and decisions in a decentralized system should not be instantaneous and error-free, and that delays in information exchange in a decentralized system lead to reasonable approaches to decentralized control. A mathematically precise notion of aggregating information is not yet available.

Thrombolysis in Acute Ischemic Stroke: A Simulation Study to Improve Pre- and in-Hospital Delays in Community Hospitals

PubMed Central

Lahr, Maarten M. H.; van der Zee, Durk-Jouke; Vroomen, Patrick C. A. J.; Luijckx, Gert-Jan; Buskens, Erik

2013-01-01

Background Various studies demonstrate better patient outcome and higher thrombolysis rates achieved by centralized stroke care compared to decentralized care, i.e. community hospitals. It remains largely unclear how to improve thrombolysis rate in decentralized care. The aim of this simulation study was to assess the impact of previously identified success factors in a central model on thrombolysis rates and patient outcome when implemented for a decentral model. Methods Based on a prospectively collected dataset of 1084 ischemic stroke patients, simulation was used to replicate current practice and estimate the effect of re-organizing decentralized stroke care to resemble a centralized model. Factors simulated included symptom onset call to help, emergency medical services transportation, and in-hospital diagnostic workup delays. Primary outcome was proportion of patients treated with thrombolysis; secondary endpoints were good functional outcome at 90 days, Onset-Treatment-Time (OTT), and OTT intervals, respectively. Results Combining all factors might increase thrombolysis rate by 7.9%, of which 6.6% ascribed to pre-hospital and 1.3% to in-hospital factors. Good functional outcome increased by 11.4%, 8.7% ascribed to pre-hospital and 2.7% to in-hospital factors. The OTT decreased 17 minutes, 7 minutes ascribed to pre-hospital and 10 minutes to in-hospital factors. An increase was observed in the proportion thrombolyzed within 1.5 hours; increasing by 14.1%, of which 5.6% ascribed to pre-hospital and 8.5% to in-hospital factors. Conclusions Simulation technique may target opportunities for improving thrombolysis rates in acute stroke. Pre-hospital factors proved to be the most promising for improving thrombolysis rates in an implementation study. PMID:24260151

Research on Coordination of Fresh Produce Supply Chain in Big Market Sales Environment

PubMed Central

Su, Juning; Liu, Chenguang

2014-01-01

In this paper, we propose two decision models for decentralized and centralized fresh produce supply chains with stochastic supply and demand and controllable transportation time. The optimal order quantity and the optimal transportation time in these two supply chain systems are derived. To improve profits in a decentralized supply chain, based on analyzing the risk taken by each participant in the supply chain, we design a set of contracts which can coordinate this type of fresh produce supply chain with stochastic supply and stochastic demand, and controllable transportation time as well. We also obtain a value range of contract parameters that can increase profits of all participants in the decentralized supply chain. The expected profits of the decentralized setting and the centralized setting are compared with respect to given numerical examples. Furthermore, the sensitivity analyses of the deterioration rate factor and the freshness factor are performed. The results of numerical examples show that the transportation time is shorter, the order quantity is smaller, the total profit of whole supply chain is less, and the possibility of cooperation between supplier and retailer is higher for the fresh produce which is more perishable and its quality decays more quickly. PMID:24764770

Research on coordination of fresh produce supply chain in big market sales environment.

PubMed

Su, Juning; Wu, Jiebing; Liu, Chenguang

2014-01-01

In this paper, we propose two decision models for decentralized and centralized fresh produce supply chains with stochastic supply and demand and controllable transportation time. The optimal order quantity and the optimal transportation time in these two supply chain systems are derived. To improve profits in a decentralized supply chain, based on analyzing the risk taken by each participant in the supply chain, we design a set of contracts which can coordinate this type of fresh produce supply chain with stochastic supply and stochastic demand, and controllable transportation time as well. We also obtain a value range of contract parameters that can increase profits of all participants in the decentralized supply chain. The expected profits of the decentralized setting and the centralized setting are compared with respect to given numerical examples. Furthermore, the sensitivity analyses of the deterioration rate factor and the freshness factor are performed. The results of numerical examples show that the transportation time is shorter, the order quantity is smaller, the total profit of whole supply chain is less, and the possibility of cooperation between supplier and retailer is higher for the fresh produce which is more perishable and its quality decays more quickly.

Feasibility of Decentralized Linear-Quadratic-Gaussian Control of Autonomous Distributed Spacecraft

NASA Technical Reports Server (NTRS)

Carpenter, J. Russell

1999-01-01

A distributed satellite formation, modeled as an arbitrary number of fully connected nodes in a network, could be controlled using a decentralized controller framework that distributes operations in parallel over the network. For such problems, a solution that minimizes data transmission requirements, in the context of linear-quadratic-Gaussian (LQG) control theory, was given by Speyer. This approach is advantageous because it is non-hierarchical, detected failures gracefully degrade system performance, fewer local computations are required than for a centralized controller, and it is optimal with respect to the standard LQG cost function. Disadvantages of the approach are the need for a fully connected communications network, the total operations performed over all the nodes are greater than for a centralized controller, and the approach is formulated for linear time-invariant systems. To investigate the feasibility of the decentralized approach to satellite formation flying, a simple centralized LQG design for a spacecraft orbit control problem is adapted to the decentralized framework. The simple design uses a fixed reference trajectory (an equatorial, Keplerian, circular orbit), and by appropriate choice of coordinates and measurements is formulated as a linear time-invariant system.

Evaluating the Life Cycle Environmental Benefits and Trade-Offs of Water Reuse Systems for Net-Zero Buildings.

PubMed

Hasik, Vaclav; Anderson, Naomi E; Collinge, William O; Thiel, Cassandra L; Khanna, Vikas; Wirick, Jason; Piacentini, Richard; Landis, Amy E; Bilec, Melissa M

2017-02-07

Aging water infrastructure and increased water scarcity have resulted in higher interest in water reuse and decentralization. Rating systems for high-performance buildings implicitly promote the use of building-scale, decentralized water supply and treatment technologies. It is important to recognize the potential benefits and trade-offs of decentralized and centralized water systems in the context of high-performance buildings. For this reason and to fill a gap in the current literature, we completed a life cycle assessment (LCA) of the decentralized water system of a high-performance, net-zero energy, net-zero water building (NZB) that received multiple green building certifications and compared the results with two modeled buildings (conventional and water efficient) using centralized water systems. We investigated the NZB's impacts over varying lifetimes, conducted a break-even analysis, and included Monte Carlo uncertainty analysis. The results show that, although the NZB performs better in most categories than the conventional building, the water efficient building generally outperforms the NZB. The lifetime of the NZB, septic tank aeration, and use of solar energy have been found to be important factors in the NZB's impacts. While these findings are specific to the case study building, location, and treatment technologies, the framework for comparison of water and wastewater impacts of various buildings can be applied during building design to aid decision making. As we design and operate high-performance buildings, the potential trade-offs of advanced decentralized water treatment systems should be considered.

Treatment Outcomes in a Decentralized Antiretroviral Therapy Program: A Comparison of Two Levels of Care in North Central Nigeria

PubMed Central

Okonkwo, Prosper; Sagay, Atiene S.; Agaba, Patricia A.; Yohanna, Stephen; Agbaji, Oche O.; Imade, Godwin E.; Banigbe, Bolanle; Adeola, Juliet; Oyebode, Tinuade A.; Idoko, John A.; Kanki, Phyllis J.

2014-01-01

Background. Decentralization of antiretroviral therapy (ART) services is a key strategy to achieving universal access to treatment for people living with HIV/AIDS. Our objective was to assess clinical and laboratory outcomes within a decentralized program in Nigeria. Methods. Using a tiered hub-and-spoke model to decentralize services, a tertiary hospital scaled down services to 13 secondary-level hospitals using national and program guidelines. We obtained sociodemographic, clinical, and immunovirologic data on previously antiretroviral drug naïve patients aged ≥15 years that received HAART for at least 6 months and compared treatment outcomes between the prime and satellite sites. Results. Out of 7,747 patients, 3729 (48.1%) were enrolled at the satellites while on HAART, prime site patients achieved better immune reconstitution based on CD4+ cell counts at 12 (P < 0.001) and 24 weeks (P < 0.001) with similar responses at 48 weeks (P = 0.11) and higher rates of viral suppression (<400 c/mL) at 12 (P < 0.001) and 48 weeks (P = 0.03), but similar responses at 24 weeks (P = 0.21). Mortality was 2.3% versus 5.0% (P < 0.001) at prime and satellite sites, while transfer rate was 8.7% versus 5.5% (P = 0.001) at prime and satellites. Conclusion. ART decentralization is feasible in resource-limited settings, but efforts have to be intensified to maintain good quality of care. PMID:25028610

Does fiscal decentralization improve health outcomes? Evidence from infant mortality in Italy.

PubMed

Cavalieri, Marina; Ferrante, Livio

2016-09-01

Despite financial and decision-making responsibilities having been increasingly devolved to lower levels of government worldwide, the potential impact of these reforms remains largely controversial. This paper investigates the hypothesis that a shift towards a higher degree of fiscal autonomy of sub-national governments could improve health outcomes, as measured by infant mortality rates. Italy is used as a case study since responsibilities for healthcare have been decentralized to regions, though the central government still retains a key role in ensuring all citizens uniform access to health services throughout the country. A linear fixed-effects regression model with robust standard errors is employed for a panel of 20 regions over the period 1996-2012 (340 observations in the full sample). Decentralization is proxied by two different indicators, capturing the degree of decision-making autonomy in the allocation of tax revenues and the extent to which regions rely on fiscal transfers from the central government. The results show that a higher proportion of tax revenues raised and/or controlled locally as well as a lower transfer dependency from the central government are consistently associated with lower infant mortality rates, ceteris paribus. The marginal benefit from fiscal decentralization, however, is not constant but depends on the level of regional wealth, favouring poorest regions. In terms of policy implications, this study outlines how the effectiveness of decentralization in improving health outcomes is contingent on the characteristics of the context in which the process takes place. Copyright © 2016 Elsevier Ltd. All rights reserved.

Controller design via structural reduced modeling by FETM

NASA Technical Reports Server (NTRS)

Yousuff, A.

1986-01-01

The Finite Element - Transfer Matrix (FETM) method has been developed to reduce the computations involved in analysis of structures. This widely accepted method, however, has certain limitations, and does not directly produce reduced models for control design. To overcome these shortcomings, a modification of FETM method has been developed. The modified FETM method easily produces reduced models that are tailored toward subsequent control design. Other features of this method are its ability to: (1) extract open loop frequencies and mode shapes with less computations, (2) overcome limitations of the original FETM method, and (3) simplify the procedures for output feedback, constrained compensation, and decentralized control. This semi annual report presents the development of the modified FETM, and through an example, illustrates its applicability to an output feedback and a decentralized control design.

Wave scheduling - Decentralized scheduling of task forces in multicomputers

NASA Technical Reports Server (NTRS)

Van Tilborg, A. M.; Wittie, L. D.

1984-01-01

Decentralized operating systems that control large multicomputers need techniques to schedule competing parallel programs called task forces. Wave scheduling is a probabilistic technique that uses a hierarchical distributed virtual machine to schedule task forces by recursively subdividing and issuing wavefront-like commands to processing elements capable of executing individual tasks. Wave scheduling is highly resistant to processing element failures because it uses many distributed schedulers that dynamically assign scheduling responsibilities among themselves. The scheduling technique is trivially extensible as more processing elements join the host multicomputer. A simple model of scheduling cost is used by every scheduler node to distribute scheduling activity and minimize wasted processing capacity by using perceived workload to vary decentralized scheduling rules. At low to moderate levels of network activity, wave scheduling is only slightly less efficient than a central scheduler in its ability to direct processing elements to accomplish useful work.

[Significant changes in the health system decentralization process in Brazil].

PubMed

Viana, Ana Luiza d'Avila; Heimann, Luiza S; de Lima, Luciana Dias; de Oliveira, Roberta Gondim; Rodrigues, Sergio da Hora

2002-01-01

This article discusses the trends and limits of the Brazilian health system decentralization process, identifying the three elements that constitute the strategic induction performed by the national system administrator in accordance with the guidelines contained in the Operational Norms of the Unified National Health System: systemic rationality, intergovernmental and service provider financing, and health care model. The effects of the Federal regulations are analyzed based on the results of the evaluation study focused on the implementation of the full management scheme at the Municipal level. The decentralization strategy induced by Basic Operational Norm 96 has succeeded in improving institutional conditions, management autonomy, and supply, as measured by the Federal resources transferred, installed capacity, production, and coverage of outpatient and hospital services, with the Municipalities authorized to conduct fully autonomous management, without altering the existing patterns of inequity in the distribution of funds to poorer Municipalities.

Using Economic Experiments to Test Electricity Policy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kiesling, Lynne

2005-11-01

The industry's history of central generation, coordination, and regulation breeds a natural suspicion of whether or not decentralized coordination and a more market-based, decentralized regulatory approach can work. To see how people will behave in a decentralized environment with decentralized institutions, one must test the environment and institutions experimentally, with real people.

Educational Decentralization, Public Spending, and Social Justice in Nigeria

ERIC Educational Resources Information Center

Geo-Jaja, Macleans A.

2006-01-01

This study situates the process of educational decentralization in the narrower context of social justice. Its main object, however, is to analyze the implications of decentralization for strategies of equity and social justice in Nigeria. It starts from the premise that the early optimism that supported decentralization as an efficient and…

Optimal decentralized feedback control for a truss structure

NASA Technical Reports Server (NTRS)

Cagle, A.; Ozguner, U.

1989-01-01

One approach to the decentralized control of large flexible space structures involves the design of controllers for the substructures of large systems and their subsequent application to the entire coupled system. This approach is presently developed for the case of active vibration damping on an experimental large struss structure. The isolated boundary loading method is used to define component models by FEM; component controllers are designed using an interlocking control concept which minimizes the motion of the boundary nodes, thereby reducing the exchange of mechanical disturbances among components.

Decentralization: Why, How, and toward What Ends? Special Policy Report, No. 1. Policy Briefs Series.

ERIC Educational Resources Information Center

Stinnette, Lynn J.

Administrators are looking at decentralization as a solution to issues troubling schools, teachers, and students. The notion of decentralization is accompanied by two assumptions. First, decentralization will produce an improvement in education because classroom decision making will be more responsive to the specific needs of a school. Second, in…

Decentralized Planning for Autonomous Agents Cooperating in Complex Missions

DTIC Science & Technology

2010-09-01

Consensus - based decentralized auctions for robust task allocation ," IEEE Transactions on Robotics...Robotics, vol. 24, pp. 209-222, 2006. [44] H.-L. Choi, L. Brunet, and J. P. How, " Consensus - based decentralized auctions for robust task allocation ...2003. 123 [31] L. Brunet, " Consensus - Based Auctions for Decentralized Task Assignment," Master’s thesis, Dept.

The political economy of decentralization of health and social services in Canada.

PubMed

Tsalikis, G

1989-01-01

A trend to decentralization in Canada's 'welfare state' has received support from the Left and from the Right. Some social critics of the Left expect decentralization to result in holistic services adjusted to local needs. Others, moreover, feel we are in the dawn of a new epoch in which major economic transformations are to bring about, through new class alliances and conflict, decentralization of power and a better quality of life in communities. These assumptions and their theoretical pitfalls are discussed here following an historical overview of the centralization/decentralization issue in Canadian social policy. It is argued that recent proposals of decentralization are a continuation of reactionary tendencies to constrain social expenditures, but not a path to better quality of life.

Combatting Global Infectious Diseases: A Network Effect of Specimen Referral Systems.

PubMed

Fonjungo, Peter N; Alemnji, George A; Kebede, Yenew; Opio, Alex; Mwangi, Christina; Spira, Thomas J; Beard, R Suzanne; Nkengasong, John N

2017-02-13

The recent Ebola virus outbreak in West Africa clearly demonstrated the critical role of laboratory systems and networks in responding to epidemics. Because of the huge challenges in establishing functional laboratories at all tiers of health systems in developing countries, strengthening specimen referral networks is critical. In this review article, we propose a platform strategy for developing specimen referral networks based on 2 models: centralized and decentralized laboratory specimen referral networks. These models have been shown to be effective in patient management in programs in resource-limited settings. Both models lead to reduced turnaround time and retain flexibility for integrating different specimen types. In Haiti, decentralized specimen referral systems resulted in a 182% increase in patients enrolling in human immunodeficiency virus treatment programs within 6 months. In Uganda, cost savings of up to 62% were observed with a centralized model. A platform strategy will create a network effect that will benefit multiple disease programs.

From microbes to water districts: Linking observations across scales to uncover the implications of riparian and channel management on water quality in an irrigated agricultural landscape

NASA Astrophysics Data System (ADS)

Webster, A.; Cadenasso, M. L.

2016-12-01

Interactions among runoff, riparian and stream ecosystems, and water quality remain uncertain in many settings, particularly those heavily impacted by human activities. For example, waterways in the irrigated agricultural landscape of California's Central Valley are seasonally disconnected from groundwater tables and are extensively modified by infrastructure and management. These conditions make the impact of riparian and channel management difficult to predict across scales, which hinders efforts to promote best management practices to improve water quality. We seek to link observations across catchment, reach, and patch scales to understand patterns of nitrate and turbidity in waterways draining irrigated cropland. Data was collected on 80 reaches spanning two water management districts. At the catchment scale, water districts implemented waterway and riparian management differently: one water district had a decentralized approach, allowing individual land owners to manage their waterway channels and banks, while the other had a centralized approach, in which land owners defer management to a district-run program. At the reach scale, riparian and waterway vegetation, geomorphic complexity, and flow conditions were quantified. Reach-scale management such as riparian planting projects and channel dredging frequency were also considered. At the patch scale, denitrification potential and organic matter were measured in riparian toe-slope soils and channel sediments, along with associated vegetation and geomorphic features. All factors were tested for their ability to predict water quality using generalized linear mixed effects models and the consistency of predictors within and across scales was evaluated. A hierarchy of predictors emerges: catchment-scale management regimes predict reach-scale geomorphic and vegetation complexity, which in turn predicts sediment denitrification potential - the patch-scale factor most associated with low nitrate. Similarly, turbidity conveyance was most associated with reach-scale factors. These findings suggest that, in the absence of other regulations, a decentralized management approach to riparian zones and waterways allows reach-scale complexity to arise, which in turn promotes ecosystem function and improved water quality.

Administrative Decentralization in School Systems and Its Effect on the Organization of Media Services. Atlanta Public Schools: A Case Study.

ERIC Educational Resources Information Center

Williams, R. David

This study reviews the literature on public school administration and on decentralization to establish the groundwork for an analysis of the administration of a decentralized school system and its media services, discusses some of the confusion in the centralization vs. decentralization debate, and presents a heuristic study of the administration…

Decentralization of Education: Why, When, What, and How? Fundamentals of Educational Planning Series, Number 64.

ERIC Educational Resources Information Center

Welsh, Thomas; McGinn, Noel F.

Decentralization is arguably one of the most important phenomena to come on to the educational planning agenda in the last 15 years. Why a country should decentralize its educational decision-making process and which decisions should be decentralized are two questions that many decision-makers raise. This booklet is intended to provide educational…

The tradeoff between centralized and decentralized health services: evidence from rural areas in Mexico.

PubMed

Vargas Bustamante, Arturo

2010-09-01

This study investigates the effectiveness of centralized and decentralized health care providers in rural Mexico. It compares provider performance since both centralized and decentralized providers co-exist in rural areas of the country. The data are drawn from the 2003 household survey of Oportunidades, a comprehensive study of rural families from seven states in Mexico. The analyses compare out-of-pocket health care expenditures and utilization of preventive care among rural households with access to either centralized or decentralized health care providers. This study benefits from differences in timing of health care decentralization and from a quasi-random distribution of providers. Results show that overall centralized providers perform better. Households served by this organization report less regressive out-of-pocket health care expenditures (32% lower), and observe higher utilization of preventive services (3.6% more). Decentralized providers that were devolved to state governments in the early 1980s observe a slightly better performance than providers that were decentralized in the mid-1990s. These findings are robust to decentralization timing, heterogeneity in per capita government health expenditures, state and health infrastructure effects, and other confounders. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Decentralization of health care systems and health outcomes: Evidence from a natural experiment.

PubMed

Jiménez-Rubio, Dolores; García-Gómez, Pilar

2017-09-01

While many countries worldwide are shifting responsibilities for their health systems to local levels of government, there is to date insufficient evidence about the potential impact of these policy reforms. We estimate the impact of decentralization of the health services on infant and neonatal mortality using a natural experiment: the devolution of health care decision making powers to Spanish regions. The devolution was implemented gradually and asymmetrically over a twenty-year period (1981-2002). The order in which the regions were decentralized was driven by political factors and hence can be considered exogenous to health outcomes. In addition, we exploit the dynamic effect of decentralization of health services and allow for heterogeneous effects by the two main types of decentralization implemented across regions: full decentralization (political and fiscal powers) versus political decentralization only. Our difference in differences results based on a panel dataset for the 50 Spanish provinces over the period 1980 to 2010 show that the lasting benefit of decentralization accrues only to regions which enjoy almost full fiscal and political powers and which are also among the richest regions. Copyright © 2017 Elsevier Ltd. All rights reserved.

The snow system: A decentralized medical data processing system.

PubMed

Bellika, Johan Gustav; Henriksen, Torje Starbo; Yigzaw, Kassaye Yitbarek

2015-01-01

Systems for large-scale reuse of electronic health record data is claimed to have the potential to transform the current health care delivery system. In principle three alternative solutions for reuse exist: centralized, data warehouse, and decentralized solutions. This chapter focuses on the decentralized system alternative. Decentralized systems may be categorized into approaches that move data to enable computations or move computations to the where data is located to enable computations. We describe a system that moves computations to where the data is located. Only this kind of decentralized solution has the capabilities to become ideal systems for reuse as the decentralized alternative enables computation and reuse of electronic health record data without moving or exposing the information to outsiders. This chapter describes the Snow system, which is a decentralized medical data processing system, its components and how it has been used. It also describes the requirements this kind of systems need to support to become sustainable and successful in recruiting voluntary participation from health institutions.

A Modified Actor-Power-Accountability Framework (MAPAF) for analyzing decentralized forest governance: case study from Ethiopia.

PubMed

Mohammed, Abrar Juhar; Inoue, Makoto

2014-06-15

This paper posits a Modified Actor-Power-Accountability Framework (MAPAF) that makes three major improvements on the Actor-Power-Accountability Framework (APAF) developed by Agrawal and Ribot (1999). These improvements emphasize the nature of decentralized property rights, linking the outputs of decentralization with its outcomes and the inclusion of contextual factors. Applying MAPAF to analyze outputs and outcomes from two major decentralized forest policies in Ethiopia, i.e., delegation and devolution, has demonstrated the following strengths of the framework. First, by incorporating vital bundles of property rights into APAF, MAPAF creates a common ground for exploring and comparing the extent of democratization achieved by different decentralizing reforms. Second, the inclusion of social and environmental outcomes in MAPAF makes it possible to link the output of decentralization with local level outcomes. Finally, the addition of contextual factors enhances MAPAF's explanatory power by providing room for investigating exogenous factors other than democratization that contribute to the outcomes of decentralization reforms. Copyright © 2014 Elsevier Ltd. All rights reserved.

Variations of pupil centration and their effects on video eye tracking.

PubMed

Wildenmann, Ulrich; Schaeffel, Frank

2013-11-01

To evaluate measurement errors that are introduced in video eye tracking when pupil centration changes with pupil size. Software was developed under Visual C++ to track both pupil centre and corneal centre at 87 Hz sampling rate at baseline pupil sizes of 4.75 mm (800 lux room illuminance) and while pupil constrictions were elicited by a flashlight. Corneal centres were determined by a circle fit through the pixels detected at the corneal margin by an edge detection algorithm. Standard deviations for repeated measurements were ± 0.04 mm for horizontal pupil centre position and ± 0.04 mm for horizontal corneal centre positions and ±0.03 mm for vertical pupil centre position and ± 0.05 mm for vertical corneal centre position. Ten subjects were tested (five female, five male, age 25-58 years). At 4 mm pupil sizes, the pupils were nasally decentred relative to the corneal centre by 0.18 ± 0.19 mm in the right eyes and -0.14 ± 0.22 mm in the left eyes. Vertical decentrations were 0.30 ± 0.30 mm and 0.27 ± 0.29 mm, respectively, always in a superior direction. At baseline pupil sizes (the natural pupil sizes at 800 lux) of 4.75 ± 0.52 mm, the decentrations became less (right and left eyes: horizontal 0.17 ± 0.20 mm and -0.12 ± 0.22 mm, and vertical 0.26 ± 0.28 mm and 0.20 ± 0.25 mm). While pupil decentration changed minimally in eight of the subjects, it shifted considerably in two others. Averaged over all subjects, the shift of the pupil centre position per millimetre pupil constriction was not significant (right and left eyes: -0.03 ± 0.07 mm and 0.03 ± 0.04 mm nasally per mm pupil size change, respectively, and -0.04 ± 0.06 mm and -0.05 ± 0.12 mm superiorly). Direction and magnitude of the changes in pupil centration could not be predicted from the initial decentration at baseline pupil sizes. In line with data in the literature, the pupil centre was significantly decentred relative to the corneal centre in the nasal and superior direction. Pupil decentration changed significantly with pupil size by 0.05 mm on average for 1 mm of constriction. Assuming a Hirschberg ratio of 12° mm(-1) , a shift of 0.05 mm is equivalent to a measurement error in a Purkinje image-based eye tracker of 0.6°. However, the induced measurement error could also exceed 1.5° in some subjects for only a 1 mm change in pupil size. © 2013 The Authors Ophthalmic & Physiological Optics © 2013 The College of Optometrists.

Decentralized control scheme for myriapod robot inspired by adaptive and resilient centipede locomotion.

PubMed

Yasui, Kotaro; Sakai, Kazuhiko; Kano, Takeshi; Owaki, Dai; Ishiguro, Akio

2017-01-01

Recently, myriapods have attracted the attention of engineers because mobile robots that mimic them potentially have the capability of producing highly stable, adaptive, and resilient behaviors. The major challenge here is to develop a control scheme that can coordinate their numerous legs in real time, and an autonomous decentralized control could be the key to solve this problem. Therefore, we focus on real centipedes and aim to design a decentralized control scheme for myriapod robots by drawing inspiration from behavioral experiments on centipede locomotion under unusual conditions. In the behavioral experiments, we observed the response to the removal of a part of the terrain and to amputation of several legs. Further, we determined that the ground reaction force is significant for generating rhythmic leg movements; the motion of each leg is likely affected by a sensory input from its neighboring legs. Thus, we constructed a two-dimensional model wherein a simple local reflexive mechanism was implemented in each leg. We performed simulations by using this model and demonstrated that the myriapod robot could move adaptively to changes in the environment and body properties. Our findings will shed new light on designing adaptive and resilient myriapod robots that can function under various circumstances.

Spatial optimization for decentralized non-potable water reuse

NASA Astrophysics Data System (ADS)

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.

Decentralization, democratization, and health: the Philippine experiment.

PubMed

Langran, Irene V

2011-01-01

In 1991, the Philippines joined a growing list of countries that reformed health planning through decentralization. Reformers viewed decentralization as a tool that would solve multiple problems, leading to more meaningful democracy and more effective health planning. Today, nearly two decades after the passage of decentralization legislation, questions about the effectiveness of the reforms persist. Inadequate financing, inequity, and a lack of meaningful participation remain challenges, in many ways mirroring broader weaknesses of Philippine democracy. These concerns pose questions regarding the nature of contemporary decentralization, democratization, and health planning and whether these three strategies are indeed mutually enforcing.

Comparison of a hybrid medication distribution system to simulated decentralized distribution models.

PubMed

Gray, John P; Ludwig, Brad; Temple, Jack; Melby, Michael; Rough, Steve

2013-08-01

The results of a study to estimate the human resource and cost implications of changing the medication distribution model at a large medical center are presented. A two-part study was conducted to evaluate alternatives to the hospital's existing hybrid distribution model (64% of doses dispensed via cart fill and 36% via automated dispensing cabinets [ADCs]). An assessment of nurse, pharmacist, and pharmacy technician workloads within the hybrid system was performed through direct observation, with time standards calculated for each dispensing task; similar time studies were conducted at a comparator hospital with a decentralized medication distribution system involving greater use of ADCs. The time study data were then used in simulation modeling of alternative distribution scenarios: one involving no use of cart fill, one involving no use of ADCs, and one heavily dependent on ADC dispensing (89% via ADC and 11% via cart fill). Simulation of the base-case and alternative scenarios indicated that as the modeled percentage of doses dispensed from ADCs rose, the calculated pharmacy technician labor requirements decreased, with a proportionately greater increase in the nursing staff workload. Given that nurses are a higher-cost resource than pharmacy technicians, the projected human resource opportunity cost of transitioning from the hybrid system to a decentralized system similar to the comparator facility's was estimated at $229,691 per annum. Based on the simulation results, it was decided that a transition from the existing hybrid medication distribution system to a more ADC-dependent model would result in an unfavorable shift in staff skill mix and corresponding human resource costs at the medical center.

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

PubMed

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.

Decentralising Curriculum Reform: The Link Teacher Model of In-Service Training.

ERIC Educational Resources Information Center

Wildy, Helen; And Others

1996-01-01

Presents a (Western Australian) case study of the link teacher model, a decentralized, "train the trainer" approach to inservice education. Discusses the model's perceived effectiveness, the link teachers' role, central authority support, and new experimentation opportunities. Combining centralized syllabus change with decentralized…

Decentralized Control of Sound Radiation from an Aircraft-Style Panel Using Iterative Loop Recovery

NASA Technical Reports Server (NTRS)

Schiller, Noah H.; Cabell, Randolph H.; Fuller, Chris R.

2008-01-01

A decentralized LQG-based control strategy is designed to reduce low-frequency sound transmission through periodically stiffened panels. While modern control strategies have been used to reduce sound radiation from relatively simple structural acoustic systems, significant implementation issues have to be addressed before these control strategies can be extended to large systems such as the fuselage of an aircraft. For instance, centralized approaches typically require a high level of connectivity and are computationally intensive, while decentralized strategies face stability problems caused by the unmodeled interaction between neighboring control units. Since accurate uncertainty bounds are not known a priori, it is difficult to ensure the decentralized control system will be robust without making the controller overly conservative. Therefore an iterative approach is suggested, which utilizes frequency-shaped loop recovery. The approach accounts for modeling error introduced by neighboring control loops, requires no communication between subsystems, and is relatively simple. The control strategy is validated using real-time control experiments performed on a built-up aluminum test structure representative of the fuselage of an aircraft. Experiments demonstrate that the iterative approach is capable of achieving 12 dB peak reductions and a 3.6 dB integrated reduction in radiated sound power from the stiffened panel.

The Impact of Human-Automation Collaboration in Decentralized Multiple Unmanned Vehicle Control

DTIC Science & Technology

2011-01-01

based decentralized auctions for robust task allocation ,[ IEEE Trans. Robot., vol. 25, no. 4, pp...operators can aid such systems by bringing their knowledge- based reasoning and experience to bear. Given a decentralized task planner and a goal- based ...experience to bear. Given a decentralized task planner and a goal- based operator interface for a network of unmanned vehicles in a search, track,

Operator Objective Function Guidance for a Real-Time Unmanned Vehicle Scheduling Algorithm

DTIC Science & Technology

2012-12-01

Consensus - Based Decentralized Auctions for Robust Task Allocation ,” IEEE Transactions on Robotics and Automation, Vol. 25, No. 4, No. 4, 2009, pp. 912...planning for the fleet. The decentralized task planner used in OPS-USERS is the consensus - based bundle algorithm (CBBA), a decentralized , polynomial...and surveillance (OPS-USERS), which leverages decentralized algorithms for vehicle routing and task allocation . This

Relationships between digital signal processing and control and estimation theory

NASA Technical Reports Server (NTRS)

Willsky, A. S.

1978-01-01

Research directions in the fields of digital signal processing and modern control and estimation theory are discussed. Stability theory, linear prediction and parameter identification, system synthesis and implementation, two-dimensional filtering, decentralized control and estimation, and image processing are considered in order to uncover some of the basic similarities and differences in the goals, techniques, and philosophy of the disciplines.

Governing decentralization in health care under tough budget constraint: what can we learn from the Italian experience?

PubMed

Tediosi, Fabrizio; Gabriele, Stefania; Longo, Francesco

2009-05-01

In many European countries, since the World War II, there has been a trend towards decentralization of health policy to lower levels of governments, while more recently there have been re-centralization processes. Whether re-centralization will be the new paradigm of European health policy or not is difficult to say. In the Italian National Health Service (SSN) decentralization raised two related questions that might be interesting for the international debate on decentralization in health care: (a) what sort of regulatory framework and institutional balances are required to govern decentralization in health care in a heterogeneous country under tough budget constraints? (b) how can it be ensured that the most advanced parts of the country remain committed to solidarity, supporting the weakest ones? To address these questions this article describes the recent trends in SSN funding and expenditure, it reviews the strategy adopted by the Italian government for governing the decentralization process and discusses the findings to draw policy conclusions. The main lessons emerging from this experience are that: (1) when the differences in administrative and policy skills, in socio-economic standards and social capital are wide, decentralization may lead to undesirable divergent evolution paths; (2) even in decentralized systems, the role of the Central government can be very important to contain health expenditure; (3) a strong governance of the Central government may help and not hinder the enforcement of decentralization; and (4) supporting the weakest Regions and maintaining inter-regional solidarity is hard but possible. In Italy, despite an increasing role of the Central government in steering the SSN, the pattern of regional decentralization of health sector decision making does not seem at risk. Nevertheless, the Italian case confirms the complexity of decentralization and re-centralization processes that sometimes can be paradoxically reinforcing each other.

Health sector decentralization and local decision-making: Decision space, institutional capacities and accountability in Pakistan.

PubMed

Bossert, Thomas John; Mitchell, Andrew David

2011-01-01

Health sector decentralization has been widely adopted to improve delivery of health services. While many argue that institutional capacities and mechanisms of accountability required to transform decentralized decision-making into improvements in local health systems are lacking, few empirical studies exist which measure or relate together these concepts. Based on research instruments administered to a sample of 91 health sector decision-makers in 17 districts of Pakistan, this study analyzes relationships between three dimensions of decentralization: decentralized authority (referred to as "decision space"), institutional capacities, and accountability to local officials. Composite quantitative indicators of these three dimensions were constructed within four broad health functions (strategic and operational planning, budgeting, human resources management, and service organization/delivery) and on an overall/cross-function basis. Three main findings emerged. First, district-level respondents report varying degrees of each dimension despite being under a single decentralization regime and facing similar rules across provinces. Second, within dimensions of decentralization-particularly decision space and capacities-synergies exist between levels reported by respondents in one function and those reported in other functions (statistically significant coefficients of correlation ranging from ρ=0.22 to ρ=0.43). Third, synergies exist across dimensions of decentralization, particularly in terms of an overall indicator of institutional capacities (significantly correlated with both overall decision space (ρ=0.39) and accountability (ρ=0.23)). This study demonstrates that decentralization is a varied experience-with some district-level officials making greater use of decision space than others and that those who do so also tend to have more capacity to make decisions and are held more accountable to elected local officials for such choices. These findings suggest that Pakistan's decentralization policy should focus on synergies among dimensions of decentralization to encouraging more use of de jure decision space, work toward more uniform institutional capacity, and encourage greater accountability to local elected officials. Copyright © 2010 Elsevier Ltd. All rights reserved.

Highways and Urban Decentralization

DOT National Transportation Integrated Search

1998-01-01

This report documents a retrospective study of the relationship between highways and urban decentralization. We see decentralization as caused largely by the increased consumption of land by residents and businesses which occurs mainly because of hig...

Healthcare financing, decentralization and regional health planning: federal transfers and the healthcare networks in Minas Gerais, Brazil.

PubMed

Moreira, Laura Monteiro de Castro; Ferré, Felipe; Andrade, Eli Iola Gurgel

2017-04-01

The Decrees 4279/10 and 7508/11 established norms to guide health politics, with impacts on funding of the Middle and High Complexity Hospital and Outpatient. To verify the effects on the consolidation of care networks in Minas Gerais, we performed an analytical-descriptive study of the National Health Fund from 2006 to 2014. We observed decentralization of responsibilities, accompanied of resources and innovative financing mechanisms, resulting expansion of the network care model. The federal government definitions suggest reduction of the autonomy and limitation of regional solutions.

Nasa-wide Standard Administrative Systems

NASA Technical Reports Server (NTRS)

Schneck, P.

1984-01-01

Factors to be considered in developing agency-wide standard administrative systems for NASA include uniformity of hardware and software; centralization vs. decentralization; risk exposure; and models for software development.

Peeling the Onion: Why Centralized Control / Decentralized Execution Works

DTIC Science & Technology

2014-04-01

March–April 2014 Air & Space Power Journal | 24 Feature Peeling the Onion Why Centralized Control / Decentralized Execution Works Lt Col Alan Docauer...DATES COVERED 00-00-2014 to 00-00-2014 4. TITLE AND SUBTITLE Peeling the Onion : Why Centralized Control / Decentralized Execution Works 5a...Air & Space Power Journal | 25 Docauer Peeling the Onion Feature What Is Centralized Control / Decentralized Execution? Emerging in the aftermath of

Forecast of the World's Electrical Demands until 2025.

ERIC Educational Resources Information Center

Claverie, Maurice J.; Dupas, Alain P.

1979-01-01

Models of global energy demand, a lower-growth-rate model developed at Case Western Reserve University and the H5 model of the Conservation Committee of the World Energy Conference, assess the features of decentralized and centralized electricity generation in the years 2000 and 2025. (BT)

Web tools for predictive toxicology model building.

PubMed

Jeliazkova, Nina

2012-07-01

The development and use of web tools in chemistry has accumulated more than 15 years of history already. Powered by the advances in the Internet technologies, the current generation of web systems are starting to expand into areas, traditional for desktop applications. The web platforms integrate data storage, cheminformatics and data analysis tools. The ease of use and the collaborative potential of the web is compelling, despite the challenges. The topic of this review is a set of recently published web tools that facilitate predictive toxicology model building. The focus is on software platforms, offering web access to chemical structure-based methods, although some of the frameworks could also provide bioinformatics or hybrid data analysis functionalities. A number of historical and current developments are cited. In order to provide comparable assessment, the following characteristics are considered: support for workflows, descriptor calculations, visualization, modeling algorithms, data management and data sharing capabilities, availability of GUI or programmatic access and implementation details. The success of the Web is largely due to its highly decentralized, yet sufficiently interoperable model for information access. The expected future convergence between cheminformatics and bioinformatics databases provides new challenges toward management and analysis of large data sets. The web tools in predictive toxicology will likely continue to evolve toward the right mix of flexibility, performance, scalability, interoperability, sets of unique features offered, friendly user interfaces, programmatic access for advanced users, platform independence, results reproducibility, curation and crowdsourcing utilities, collaborative sharing and secure access.

Taking stock of decentralized disaster risk reduction in Indonesia

NASA Astrophysics Data System (ADS)

Grady, Anthony; Gersonius, Berry; Makarigakis, Alexandros

2016-09-01

The Sendai Framework, which outlines the global course on disaster risk reduction until 2030, places strong importance on the role of local government in disaster risk reduction. An aim of decentralization is to increase the influence and authority of local government in decision making. Yet, there is limited empirical evidence of the extent, character and effects of decentralization in current disaster risk reduction implementation, and of the barriers that are most critical to this. This paper evaluates decentralization in relation to disaster risk reduction in Indonesia, chosen for its recent actions to decentralize governance of DRR coupled with a high level of disaster risk. An analytical framework was developed to evaluate the various dimensions of decentralized disaster risk reduction, which necessitated the use of a desk study, semi-structured interviews and a gap analysis. Key barriers to implementation in Indonesia included: capacity gaps at lower institutional levels, low compliance with legislation, disconnected policies, issues in communication and coordination and inadequate resourcing. However, any of these barriers are not unique to disaster risk reduction, and similar barriers have been observed for decentralization in other developing countries in other public sectors.

A decentralized linear quadratic control design method for flexible structures

NASA Technical Reports Server (NTRS)

Su, Tzu-Jeng; Craig, Roy R., Jr.

1990-01-01

A decentralized suboptimal linear quadratic control design procedure which combines substructural synthesis, model reduction, decentralized control design, subcontroller synthesis, and controller reduction is proposed for the design of reduced-order controllers for flexible structures. The procedure starts with a definition of the continuum structure to be controlled. An evaluation model of finite dimension is obtained by the finite element method. Then, the finite element model is decomposed into several substructures by using a natural decomposition called substructuring decomposition. Each substructure, at this point, still has too large a dimension and must be reduced to a size that is Riccati-solvable. Model reduction of each substructure can be performed by using any existing model reduction method, e.g., modal truncation, balanced reduction, Krylov model reduction, or mixed-mode method. Then, based on the reduced substructure model, a subcontroller is designed by an LQ optimal control method for each substructure independently. After all subcontrollers are designed, a controller synthesis method called substructural controller synthesis is employed to synthesize all subcontrollers into a global controller. The assembling scheme used is the same as that employed for the structure matrices. Finally, a controller reduction scheme, called the equivalent impulse response energy controller (EIREC) reduction algorithm, is used to reduce the global controller to a reasonable size for implementation. The EIREC reduced controller preserves the impulse response energy of the full-order controller and has the property of matching low-frequency moments and low-frequency power moments. An advantage of the substructural controller synthesis method is that it relieves the computational burden associated with dimensionality. Besides that, the SCS design scheme is also a highly adaptable controller synthesis method for structures with varying configuration, or varying mass and stiffness properties.

Dynamic Centralized and Decentralized Control Systems

DOT National Transportation Integrated Search

1977-09-01

This report develops a systematic method for designing suboptimal decentralized control systems. The method is then applied to the design of a decentralized controller for a freeway-corridor system. A freeway corridor is considered to be a system of ...

A comparison of decentralized, distributed, and centralized vibro-acoustic control.

PubMed

Frampton, Kenneth D; Baumann, Oliver N; Gardonio, Paolo

2010-11-01

Direct velocity feedback control of structures is well known to increase structural damping and thus reduce vibration. In multi-channel systems the way in which the velocity signals are used to inform the actuators ranges from decentralized control, through distributed or clustered control to fully centralized control. The objective of distributed controllers is to exploit the anticipated performance advantage of the centralized control while maintaining the scalability, ease of implementation, and robustness of decentralized control. However, and in seeming contradiction, some investigations have concluded that decentralized control performs as well as distributed and centralized control, while other results have indicated that distributed control has significant performance advantages over decentralized control. The purpose of this work is to explain this seeming contradiction in results, to explore the effectiveness of decentralized, distributed, and centralized vibro-acoustic control, and to expand the concept of distributed control to include the distribution of the optimization process and the cost function employed.

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

PubMed

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.

Decentralized System Identification Using Stochastic Subspace Identification for Wireless Sensor Networks

PubMed Central

Cho, Soojin; Park, Jong-Woong; Sim, Sung-Han

2015-01-01

Wireless sensor networks (WSNs) facilitate a new paradigm to structural identification and monitoring for civil infrastructure. Conventional structural monitoring systems based on wired sensors and centralized data acquisition systems are costly for installation as well as maintenance. WSNs have emerged as a technology that can overcome such difficulties, making deployment of a dense array of sensors on large civil structures both feasible and economical. However, as opposed to wired sensor networks in which centralized data acquisition and processing is common practice, WSNs require decentralized computing algorithms to reduce data transmission due to the limitation associated with wireless communication. In this paper, the stochastic subspace identification (SSI) technique is selected for system identification, and SSI-based decentralized system identification (SDSI) is proposed to be implemented in a WSN composed of Imote2 wireless sensors that measure acceleration. The SDSI is tightly scheduled in the hierarchical WSN, and its performance is experimentally verified in a laboratory test using a 5-story shear building model. PMID:25856325

Interdependent Network Recovery Games.

PubMed

Smith, Andrew M; González, Andrés D; Dueñas-Osorio, Leonardo; D'Souza, Raissa M

2017-10-30

Recovery of interdependent infrastructure networks in the presence of catastrophic failure is crucial to the economy and welfare of society. Recently, centralized methods have been developed to address optimal resource allocation in postdisaster recovery scenarios of interdependent infrastructure systems that minimize total cost. In real-world systems, however, multiple independent, possibly noncooperative, utility network controllers are responsible for making recovery decisions, resulting in suboptimal decentralized processes. With the goal of minimizing recovery cost, a best-case decentralized model allows controllers to develop a full recovery plan and negotiate until all parties are satisfied (an equilibrium is reached). Such a model is computationally intensive for planning and negotiating, and time is a crucial resource in postdisaster recovery scenarios. Furthermore, in this work, we prove this best-case decentralized negotiation process could continue indefinitely under certain conditions. Accounting for network controllers' urgency in repairing their system, we propose an ad hoc sequential game-theoretic model of interdependent infrastructure network recovery represented as a discrete time noncooperative game between network controllers that is guaranteed to converge to an equilibrium. We further reduce the computation time needed to find a solution by applying a best-response heuristic and prove bounds on ε-Nash equilibrium, where ε depends on problem inputs. We compare best-case and ad hoc models on an empirical interdependent infrastructure network in the presence of simulated earthquakes to demonstrate the extent of the tradeoff between optimality and computational efficiency. Our method provides a foundation for modeling sociotechnical systems in a way that mirrors restoration processes in practice. © 2017 Society for Risk Analysis.

Performance of centralized versus decentralized tuberculosis treatment services in Southern Brazil, 2006-2015.

PubMed

Scheffer, Mara Cristina; Prim, Rodrigo Ivan; Wildner, Leticia Muraro; Medeiros, Taiane Freitas; Maurici, Rosemeri; Kupek, Emil; Bazzo, Maria Luiza

2018-04-25

Tuberculosis (TB) control programs face the challenges of decreasing incidence, mortality rates, and drug resistance while increasing treatment adherence. The Brazilian TB control program recommended the decentralization of patient care as a strategy for combating the disease. This study evaluated the performance of this policy in an area with high default rates, comparing epidemiological and operational indicators between two similar municipalities. This study analyzed epidemiological and operational indicators on new cases of pulmonary tuberculosis reported in the Brazilian Notifiable Diseases Information System between 2006 and 2015. In addition, to characterize differences between the populations of the two studied municipalities, a prospective cohort study was conducted between 2014 and 2015, in which patients with new cases of culture-confirmed pulmonary tuberculosis were interviewed and monitored until the disease outcome. A descriptive analysis, the chi-square test, and a Poisson regression model were employed to compare TB treatment outcomes and health care indicators between the municipalities. Two thousand three hundred nine cases were evaluated, of which 207 patients were interviewed. Over the 2006-2015 period, TB incidence per 100,000 population in the municipality with decentralized care was significantly higher (39%, 95% CI 27-49%) in comparison to that of the municipality with centralized care. TB treatment default rate (45%, 95% CI 12-90%) was also higher in the municipality with decentralized care. During the two-year follow-up, significant differences were found between patients in centralized care and those in decentralized care regarding treatment success (84.5 vs. 66.1%), treatment default (10.7 vs. 25.8%), illicit drug use (27.7 vs. 45.9%), and homelessness (3.6 vs. 12.9%). The operational indicators revealed that the proportion of control smear tests, medical imaging, and HIV tests were all significantly higher in the centralized care. However, a significantly higher proportion of patients started treatment in the early stages of the disease in the municipality with decentralized care. These data showed a low success rate in TB treatment in both municipalities. Decentralization of TB care, alone, did not improve the main epidemiological and operational indicators related to disease control when compared to centralized care. Full implementation of strategies already recommended is needed to improve TB treatment success rates.

An Evaluation of the Preceptor Model versus the Formal Teaching Model.

ERIC Educational Resources Information Center

Shamian, Judith; Lemieux, Suzanne

1984-01-01

This study evaluated the effectiveness of two teaching methods to determine which is more effective in enhancing the knowledge base of participating nurses: the preceptor model embodies decentralized instruction by a member of the nursing staff, and the formal teaching model uses centralized teaching by the inservice education department. (JOW)

Decentralization of CD4 testing in resource-limited settings: 7 years of experience in six African countries.

PubMed

Marinucci, F; Medina-Moreno, S; Paterniti, A D; Wattleworth, M; Redfield, R R

2011-05-01

Improving access to CD4 testing in resource-limited settings can be achieved through both centralized and decentralized testing networks. Decentralized testing models are more suitable for countries where the HIV epidemic affects a large portion of rural populations. Timely access to accurate CD4 results is crucial at the primary level of the health system. For the past 7 years, the Institute of Human Virology of the University of Maryland School of Medicine has implemented a flexible and sustainable three-phase model: (1) site assessment and improvement, (2) appropriate technology selection with capacity building through practical training and laboratory mentoring, and (3) quality management system strengthening and monitoring, to support accessibility to reliable CD4 counting at the point of service. CD4 testing capacity was established in 122 of 229 (53%) laboratories supported in Nigeria, Uganda, Kenya, Zambia, Tanzania, and Rwanda. Among those in rural settings, 46% (69/151) had CD4 testing available at site level, with a functioning flow cytometer installed at 28% (8/29) and 50% (61/122) of level 1 and level 2 sites, respectively. To strengthen local capacity, a total of 1,152 laboratory technicians were trained through 188 training sessions provided both on-site and at central locations. The overall quality of CD4 total testing procedure was assessed at 76% (92/121) of the laboratories, with 25% (23/92), 34% (31/92), and 33% (30/92) of them reporting excellent, good, and satisfactory performance. Balancing country-specific factors with the location of the clinic, number of patients, and the expected workload, was crucial in adapting this flexible model for decentralizing CD4 testing. The close collaboration with local governments and private vendors was key to successfully expanding access to CD4 testing within the framework of HIV care and treatment programs and for the sustainability of medical laboratories in resource-limited settings. Copyright © 2011 International Society for Advancement of Cytometry.

An Allocation Model for Teaching and Nonteaching Staff in a Decentralized Institution.

ERIC Educational Resources Information Center

Dijkman, Frank G

1985-01-01

An allocation model for teaching and nonteaching staff developed at the University of Utrecht is characterized as highly normative, leading to lump sums to be allocated to academic departments. Details are given regarding the reasons for designing the new model and the process of implementation. (Author/MLW)

Disturbance decoupling, decentralized control and the Riccati equation

NASA Technical Reports Server (NTRS)

Garzia, M. R.; Loparo, K. A.; Martin, C. F.

1981-01-01

The disturbance decoupling and optimal decentralized control problems are looked at using identical mathematical techniques. A statement of the problems and the development of their solution approach is presented. Preliminary results are given for the optimal decentralized control problem.

A novel test method to determine the filter material service life of decentralized systems treating runoff from traffic areas.

PubMed

Huber, Maximilian; Welker, Antje; Dierschke, Martina; Drewes, Jörg E; Helmreich, Brigitte

2016-09-01

In recent years, there has been a significant increase in the development and application of technical decentralized filter systems for the treatment of runoff from traffic areas. However, there are still many uncertainties regarding the service life and the performance of filter materials that are employed in decentralized treatment systems. These filter media are designed to prevent the transport of pollutants into the environment. A novel pilot-scale test method was developed to determine - within a few days - the service lives and long-term removal efficiencies for dissolved heavy metals in stormwater treatment systems. The proposed method consists of several steps including preloading the filter media in a pilot-scale model with copper and zinc by a load of n-1 years of the estimated service life (n). Subsequently, three representative rain events are simulated to evaluate the long-term performance by dissolved copper and zinc during the last year of application. The presented results, which verified the applicability of this method, were obtained for three filter channel systems and six filter shaft systems. The performance of the evaluated systems varied largely for both tested heavy metals and during all three simulated rain events. A validation of the pilot-scale assessment method with field measurements was also performed for two systems. Findings of this study suggest that this novel method does provide a standardized and accurate estimation of service intervals of decentralized treatment systems employing various filter materials. The method also provides regulatory authorities, designers, and operators with an objective basis for performance assessment and supports stormwater managers to make decisions for the installation of such decentralized treatment systems. Copyright © 2016 Elsevier Ltd. All rights reserved.

Decentralized manufacturing of cell and gene therapies: Overcoming challenges and identifying opportunities.

PubMed

Harrison, Richard P; Ruck, Steven; Medcalf, Nicholas; Rafiq, Qasim A

2017-10-01

Decentralized or "redistributed" manufacturing has the potential to revolutionize the manufacturing approach for cell and gene therapies (CGTs), moving away from the "Fordist" paradigm, delivering health care locally, customized to the end user and, by its very nature, overcoming many of the challenges associated with manufacturing and distribution of high volume goods. In departing from the traditional centralized model of manufacturing, decentralized manufacturing divides production across sites or geographic regions. This paradigm shift imposes significant structural and organisational changes on a business presenting both hidden challenges that must be addressed and opportunities to be embraced. By profoundly adapting business practices, significant advantages can be realized through a democratized value chain, creation of professional-level jobs without geographic restriction to the central hub and a flexibility in response to external pressures and demands. To realize these potential opportunities, however, advances in manufacturing technology and support systems are required, as well as significant changes in the way CGTs are regulated to facilitate multi-site manufacturing. Decentralized manufacturing is likely to be the manufacturing platform of choice for advanced health care therapies-in particular, those with a high degree of personalization. The future success of these promising products will be enhanced by adopting sound business strategies early in development. To realize the benefits that decentralized manufacturing of CGTs has to offer, it is important to examine both the risks and the substantial opportunities present. In this research, we examine both the challenges and the opportunities this shift in business strategy represents in an effort to maximize the success of adoption. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Decentralized Quasi-Newton Methods

NASA Astrophysics Data System (ADS)

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.

Decentralization can help reduce deforestation when user groups engage with local government.

PubMed

Wright, Glenn D; Andersson, Krister P; Gibson, Clark C; Evans, Tom P

2016-12-27

Policy makers around the world tout decentralization as an effective tool in the governance of natural resources. Despite the popularity of these reforms, there is limited scientific evidence on the environmental effects of decentralization, especially in tropical biomes. This study presents evidence on the institutional conditions under which decentralization is likely to be successful in sustaining forests. We draw on common-pool resource theory to argue that the environmental impact of decentralization hinges on the ability of reforms to engage local forest users in the governance of forests. Using matching techniques, we analyze longitudinal field observations on both social and biophysical characteristics in a large number of local government territories in Bolivia (a country with a decentralized forestry policy) and Peru (a country with a much more centralized forestry policy). We find that territories with a decentralized forest governance structure have more stable forest cover, but only when local forest user groups actively engage with the local government officials. We provide evidence in support of a possible causal process behind these results: When user groups engage with the decentralized units, it creates a more enabling environment for effective local governance of forests, including more local government-led forest governance activities, fora for the resolution of forest-related conflicts, intermunicipal cooperation in the forestry sector, and stronger technical capabilities of the local government staff.

Quantitative Reevaluation of the Effects of Short- and Long-Term Removal of Descending Modulatory Inputs on the Pyloric Rhythm of the Crab, Cancer borealis1,2,3

PubMed Central

Hamood, Albert W.; Haddad, Sara A.; Otopalik, Adriane G.; Rosenbaum, Philipp

2015-01-01

Abstract The crustacean stomatogastric ganglion (STG) receives descending neuromodulatory inputs from three anterior ganglia: the paired commissural ganglia (CoGs), and the single esophageal ganglion (OG). In this paper, we provide the first detailed and quantitative analyses of the short- and long-term effects of removal of these descending inputs (decentralization) on the pyloric rhythm of the STG. Thirty minutes after decentralization, the mean frequency of the pyloric rhythm dropped from 1.20 Hz in control to 0.52 Hz. Whereas the relative phase of pyloric neuron activity was approximately constant across frequency in the controls, after decentralization this changed markedly. Nine control preparations kept for 5–6 d in vitro maintained pyloric rhythm frequencies close to their initial values. Nineteen decentralized preparations kept for 5–6 d dropped slightly in frequency from those seen at 30 min following decentralization, but then displayed stable activity over 6 d. Bouts of higher frequency activity were intermittently seen in both control and decentralized preparations, but the bouts began earlier and were more frequent in the decentralized preparations. Although the bouts may indicate that the removal of the modulatory inputs triggered changes in neuronal excitability, these changes did not produce obvious long-lasting changes in the frequency of the decentralized preparations. PMID:25914899

Decentralization can help reduce deforestation when user groups engage with local government

PubMed Central

Wright, Glenn D.; Gibson, Clark C.; Evans, Tom P.

2016-01-01

Policy makers around the world tout decentralization as an effective tool in the governance of natural resources. Despite the popularity of these reforms, there is limited scientific evidence on the environmental effects of decentralization, especially in tropical biomes. This study presents evidence on the institutional conditions under which decentralization is likely to be successful in sustaining forests. We draw on common-pool resource theory to argue that the environmental impact of decentralization hinges on the ability of reforms to engage local forest users in the governance of forests. Using matching techniques, we analyze longitudinal field observations on both social and biophysical characteristics in a large number of local government territories in Bolivia (a country with a decentralized forestry policy) and Peru (a country with a much more centralized forestry policy). We find that territories with a decentralized forest governance structure have more stable forest cover, but only when local forest user groups actively engage with the local government officials. We provide evidence in support of a possible causal process behind these results: When user groups engage with the decentralized units, it creates a more enabling environment for effective local governance of forests, including more local government-led forest governance activities, fora for the resolution of forest-related conflicts, intermunicipal cooperation in the forestry sector, and stronger technical capabilities of the local government staff. PMID:27956644

Strategies of Educational Decentralization: Key Questions and Core Issues.

ERIC Educational Resources Information Center

Hanson, E. Mark

1998-01-01

Explains key issues and forces that shape organization and management strategies of educational decentralization, using examples from Colombia, Venezuela, Argentina, Nicaragua, and Spain. Core decentralization issues include national and regional goals, planning, political stress, resource distribution, infrastructure development, and job…

Is decentralization good for logistics systems? Evidence on essential medicine logistics in Ghana and Guatemala.

PubMed

Bossert, Thomas J; Bowser, Diana M; Amenyah, Johnnie K

2007-03-01

Efficient logistics systems move essential medicines down the supply chain to the service delivery point, and then to the end user. Experts on logistics systems tend to see the supply chain as requiring centralized control to be most effective. However, many health reforms have involved decentralization, which experts fear has disrupted the supply chain and made systems less effective. There is no consensus on an appropriate methodology for assessing the effectiveness of decentralization in general, and only a few studies have attempted to address decentralization of logistics systems. This paper sets out a framework and methodology of a pioneering exploratory study that examines the experiences of decentralization in two countries, Guatemala and Ghana, and presents suggestive results of how decentralization affected the performance of their logistics systems. The analytical approach assessed decentralization using the principal author's 'decision space' approach, which defines decentralization as the degree of choice that local officials have over different health system functions. In this case the approach focused on 15 different logistics functions and measured the relationship between the degree of choice and indicators of performance for each of the functions. The results of both studies indicate that less choice (i.e. more centralized) was associated with better performance for two key functions (inventory control and information systems), while more choice (i.e. more decentralized) over planning and budgeting was associated with better performance. With different systems of procurement in Ghana and Guatemala, we found that a system with some elements of procurement that are centralized (selection of firms and prices fixed by national tender) was positively related in Guatemala but negatively related in Ghana, where a system of 'cash and carry' cost recovery allowed more local choice. The authors conclude that logistics systems can be effectively decentralized for some functions while others should remain centralized. These preliminary findings, however, should be subject to alternative methodologies to confirm the findings.

Decentralized robust nonlinear model predictive controller for unmanned aerial systems

NASA Astrophysics Data System (ADS)

Garcia Garreton, Gonzalo A.

The nonlinear and unsteady nature of aircraft aerodynamics together with limited practical range of controls and state variables make the use of the linear control theory inadequate especially in the presence of external disturbances, such as wind. In the classical approach, aircraft are controlled by multiple inner and outer loops, designed separately and sequentially. For unmanned aerial systems in particular, control technology must evolve to a point where autonomy is extended to the entire mission flight envelope. This requires advanced controllers that have sufficient robustness, track complex trajectories, and use all the vehicles control capabilities at higher levels of accuracy. In this work, a robust nonlinear model predictive controller is designed to command and control an unmanned aerial system to track complex tight trajectories in the presence of internal and external perturbance. The Flight System developed in this work achieves the above performance by using: 1. A nonlinear guidance algorithm that enables the vehicle to follow an arbitrary trajectory shaped by moving points; 2. A formulation that embeds the guidance logic and trajectory information in the aircraft model, avoiding cross coupling and control degradation; 3. An artificial neural network, designed to adaptively estimate and provide aerodynamic and propulsive forces in real-time; and 4. A mixed sensitivity approach that enhances the robustness for a nonlinear model predictive controller overcoming the effect of un-modeled dynamics, external disturbances such as wind, and measurement additive perturbations, such as noise and biases. These elements have been integrated and tested in simulation and with previously stored flight test data and shown to be feasible.

Linear time-invariant controller design for two-channel decentralized control systems

NASA Technical Reports Server (NTRS)

Desoer, Charles A.; Gundes, A. Nazli

1987-01-01

This paper analyzes a linear time-invariant two-channel decentralized control system with a 2 x 2 strictly proper plant. It presents an algorithm for the algebraic design of a class of decentralized compensators which stabilize the given plant.

Household Schooling Behaviors and Decentralization.

ERIC Educational Resources Information Center

Behrman, Jere R.; King, Elizabeth M.

2001-01-01

Presents a simple framework for (1) demonstrating how households determine schooling investments through choice and voice; and (2) considering effects of decentralization on household behaviors, given information problems. Some aspects of decentralization may increase efficiency; others may be neutral or decrease efficiency. Further research is…

Leadership in Decentralized Schools.

ERIC Educational Resources Information Center

Madsen, Jean

1997-01-01

Summarizes a study that examined principals' leadership in three private schools and its implications for decentralized public schools. With the increase of charter and privatized managed schools, principals will need to redefine their leadership styles. Private schools, as decentralized entities, offer useful perspectives on developing school…

Control and stabilization of decentralized systems

NASA Technical Reports Server (NTRS)

Byrnes, Christopher I.; Gilliam, David; Martin, Clyde F.

1989-01-01

Proceeding from the problem posed by the need to stabilize the motion of two helicopters maneuvering a single load, a methodology is developed for the stabilization of classes of decentralized systems based on a more algebraic approach, which involves the external symmetries of decentralized systems. Stabilizing local-feedback laws are derived for any class of decentralized systems having a semisimple algebra of symmetries; the helicopter twin-lift problem, as well as certain problems involving the stabilization of discretizations of distributed parameter problems, have just such algebras of symmetries.

Centralized Command, Distributed Control, and Decentralized Execution - a Command and Control Solution to US Air Force A2/AD Challenges

DTIC Science & Technology

2017-04-28

Regional Air Component Commander (the Leader) 5 CC-DC- DE Solution to A2/AD – Distributed Theater Air Control System (the System) 9 CC-DC- DE ... Control , Decentralized Execution” to a new framework of “Centralized Command, Distributed Control , and Decentralized Execution” (CC-DC- DE ).4 5 This...USAF C2 challenges in A2/AD environments describes a three-part Centralized Command, Distributed Control , and Decentralized Execution (CC-DC- DE

Game-Based Virtual Worlds as Decentralized Virtual Activity Systems

NASA Astrophysics Data System (ADS)

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).

By the Numbers.

ERIC Educational Resources Information Center

Cooper, Bruce S.; McGrath, Michael; Monahan, Brian D.; Steele, Joanne Laughlin

1999-01-01

Educators can learn from business people accounting models that can be applied to managerial accounting, integrated information systems, focused/activity-based costing, decentralized information, and mission-driven costing. A sidebar discusses measuring technology's impact. (MLF)

Preliminary analysis of the PreFlexMS molten salt once-through steam generator dynamics and control strategy

NASA Astrophysics Data System (ADS)

Trabucchi, Stefano; Casella, Francesco; Maioli, Tommaso; Elsido, Cristina; Franzini, Davide; Ramond, Mathieu

2017-06-01

Concentrated Solar Power plants (CSP) coupled with thermal storage have the potential to guarantee both flexible and continuous energy production, thus being competitive with conventional fossil fuel and hydro power plants, in terms of dispatchability and provision of ancillary services. Hence, the plant equipment and control design have to be focused on flexible operation on one hand, and on plant safety concerning the molten salt freezing on the other hand. The PreFlexMS European project aims to introduce a molten salt Once-Through Steam Generator (OTSG) within a Rankine cycle based power unit, a technology that has greater flexibility potential if compared to steam drum boilers, currently used in CSP plants. The dynamic modelling and simulation from the early design stages is, thus, of paramount importance, to assess the plant dynamic behavior and controllability, and to predict the achievable closed-loop dynamic performance, potentially saving money and time during the detailed design, construction and commissioning phases. The present paper reports the main results of the analysis carried out during the first part of the project, regarding the system analysis and control design. In particular, two different control systems have been studied and tested with the plant dynamic model: a decentralized control strategy based on PI controllers and a Linear Model Predictive Control (LMPC).

Attitudes and perceptions of stakeholders on decentralization of health services in Uganda: the case of Lira and Apac districts.

PubMed

Anokbonggo, W W; Ogwal-Okeng, J W; Ross-Degnan, D; Aupont, O

2004-02-01

In Uganda, the decentralization of administrative functions, management, and responsibility for health care to districts, which began in 1994, resulted in fundamental changes in health care delivery. Since the introduction of the policy in Uganda, little information has been available on stakeholders' perceptions about the benefits of the policy and how decentralization affected health care delivery. To identify the perceptions and beliefs of key stakeholders on the impact and process of decentralization and on the operations of health services in two districts in Uganda, and to report their suggestions to improve future implementation of similar policies. We used qualitative research methods that included focus group discussions with 90 stakeholders from both study districts. The sample population comprised of 12 health workers from the two hospitals, 11 district health administrators, and 67 Local Council Leaders. Perceptions and concerns of stakeholders on the impact of decentralization on district health services. There was a general consensus that decentralization empowered local administrative and political decision-making. Among stakeholders, the policy was perceived to have created a sense of ownership and responsibility. Major problems that were said to be associated with decentralization included political harassment of civil servants, increased nepotism, inadequate financial resources, and mismanagement of resources. This study elicited perceptions about critical factors upon which successful implementation of the decentralization policy depended. These included: appreciation of the role of all stakeholders by district politicians; adequate availability and efficient utilization of resources; reasonably developed infrastructure prior to the policy change; appropriate sensitisation and training of those implementing policies; and the good will and active involvement of the local community. In the absence of these factors, implementation of decentralization of services to districts may not immediately make economic and administrative sense.

Distance Teacher Education in Pakistan

ERIC Educational Resources Information Center

Jumani, Nabi Bux; Zai, Zafar Iqbal Yousuf

2009-01-01

Distance education means instruction in which the instructor and student are separated by distance and interact through the assistance of communication technology. Distance education changes the learning relationship from the common, centralized school model to a more decentralized, flexible model. It also reverses social dynamics by bringing…

Educational decentralization, public spending, and social justice in Nigeria

NASA Astrophysics Data System (ADS)

Geo-Jaja, Macleans A.

2007-01-01

This study situates the process of educational decentralization in the narrower context of social justice. Its main object, however, is to analyze the implications of decentralization for strategies of equity and social justice in Nigeria. It starts from the premise that the early optimism that supported decentralization as an efficient and effective educational reform tool has been disappointed. The author maintains that decentralization — on its own — cannot improve education service delivery, the capacities of subordinate governments, or the integration of social policy in broader development goals. If the desired goals are to be met, public spending must be increased, greater tax revenues must be secured, and macro-economic stabilization must be achieved without re-instituting the welfare state.

Distributed architecture and distributed processing mode in urban sewage treatment

NASA Astrophysics Data System (ADS)

Zhou, Ruipeng; Yang, Yuanming

2017-05-01

Decentralized rural sewage treatment facility over the broad area, a larger operation and management difficult, based on the analysis of rural sewage treatment model based on the response to these challenges, we describe the principle, structure and function in networking technology and network communications technology as the core of distributed remote monitoring system, through the application of case analysis to explore remote monitoring system features in a decentralized rural sewage treatment facilities in the daily operation and management. Practice shows that the remote monitoring system to provide technical support for the long-term operation and effective supervision of the facilities, and reduced operating, maintenance and supervision costs for development.

Decentralization and equity of resource allocation: evidence from Colombia and Chile.

PubMed Central

Bossert, Thomas J.; Larrañaga, Osvaldo; Giedion, Ursula; Arbelaez, José Jesus; Bowser, Diana M.

2003-01-01

OBJECTIVE: To investigate the relation between decentralization and equity of resource allocation in Colombia and Chile. METHODS: The "decision space" approach and analysis of expenditures and utilization rates were used to provide a comparative analysis of decentralization of the health systems of Colombia and Chile. FINDINGS: Evidence from Colombia and Chile suggests that decentralization, under certain conditions and with some specific policy mechanisms, can improve equity of resource allocation. In these countries, equitable levels of per capita financial allocations at the municipal level were achieved through different forms of decentralization--the use of allocation formulae, adequate local funding choices and horizontal equity funds. Findings on equity of utilization of services were less consistent, but they did show that increased levels of funding were associated with increased utilization. This suggests that improved equity of funding over time might reduce inequities of service utilization. CONCLUSION: Decentralization can contribute to, or at least maintain, equitable allocation of health resources among municipalities of different incomes. PMID:12751417

Reliable Decentralized Control of Fuzzy Discrete-Event Systems and a Test Algorithm.

PubMed

Liu, Fuchun; Dziong, Zbigniew

2013-02-01

A framework for decentralized control of fuzzy discrete-event systems (FDESs) has been recently presented to guarantee the achievement of a given specification under the joint control of all local fuzzy supervisors. As a continuation, this paper addresses the reliable decentralized control of FDESs in face of possible failures of some local fuzzy supervisors. Roughly speaking, for an FDES equipped with n local fuzzy supervisors, a decentralized supervisor is called k-reliable (1 ≤ k ≤ n) provided that the control performance will not be degraded even when n - k local fuzzy supervisors fail. A necessary and sufficient condition for the existence of k-reliable decentralized supervisors of FDESs is proposed by introducing the notions of M̃uc-controllability and k-reliable coobservability of fuzzy language. In particular, a polynomial-time algorithm to test the k-reliable coobservability is developed by a constructive methodology, which indicates that the existence of k-reliable decentralized supervisors of FDESs can be checked with a polynomial complexity.

The Kerala Decentration Meter. A new method and devise for fitting the optical of spectacle lenses in the visual axis.

PubMed

Joseph, T K; Kartha, C P

1982-01-01

Centring of spectacle lenses is much neglected field of ophthalmology. The prismatic effect caused by wrong centring results in a phoria on the eye muscles which in turn causes persistent eyestrain. The theory of visual axis, optical axis and angle alpha is discussed. Using new methods the visual axis and optical axis of 35 subjects were measured. The results were computed for facial asymmetry, parallax error, angle alpha and also decentration for near vision. The results show that decentration is required on account of each of these factors. Considerable correction is needed in the vertical direction, a fact much neglected nowadays; and vertical decentration results in vertical phoria which is more symptomatic than horizontal phorias. Angle Alpha was computed for each of these patients. A new devise called 'The Kerala Decentration Meter' using the pinhole method for measuring the degree of decentration from the datum centre of the frame, and capable of correcting all the factors described above, is shown with diagrams.

Factors influencing flap and INTACS decentration after femtosecond laser application in normal and keratoconic eyes.

PubMed

Ertan, Aylin; Karacal, Humeyra

2008-10-01

To compare accuracy of LASIK flap and INTACS centration following femtosecond laser application in normal and keratoconic eyes. This is a retrospective case series comprising 133 eyes of 128 patients referred for refractive surgery. All eyes were divided into two groups according to preoperative diagnosis: group 1 (LASIK group) comprised 74 normal eyes of 72 patients undergoing LASIK with a femtosecond laser (IntraLase), and group 2 (INTACS group) consisted of 59 eyes of 39 patients with keratoconus for whom INTACS were implanted using a femtosecond laser (IntraLase). Decentration of the LASIK flap and INTACS was analyzed using Pentacam. Temporal decentration was 612.56 +/- 384.24 microm (range: 30 to 2120 microm) in the LASIK group and 788.33 +/- 500.34 microm (range: 30 to 2450 microm) in the INTACS group. A statistically significant difference was noted between the groups in terms of decentration (P < .05). Regression analysis showed that the amount of decentration of the LASIK flap and INTACS correlated with the central corneal thickness in the LASIK group and preoperative sphere and cylinder in the INTACS group, respectively. Decentration with the IntraLase occurred in most cases, especially in keratoconic eyes. The applanation performed for centralization during IntraLase application may flatten and shift the pupil center, and thus cause decentralization of the LASIK flap and INTACS. Central corneal thickness in the LASIK group and preoperative sphere and cylinder in the INTACS group proved to be statistically significant parameters associated with decentration.

COINSTAC: A Privacy Enabled Model and Prototype for Leveraging and Processing Decentralized Brain Imaging Data.

PubMed

Plis, Sergey M; Sarwate, Anand D; Wood, Dylan; Dieringer, Christopher; Landis, Drew; Reed, Cory; Panta, Sandeep R; Turner, Jessica A; Shoemaker, Jody M; Carter, Kim W; Thompson, Paul; Hutchison, Kent; Calhoun, Vince D

2016-01-01

The field of neuroimaging has embraced the need for sharing and collaboration. Data sharing mandates from public funding agencies and major journal publishers have spurred the development of data repositories and neuroinformatics consortia. However, efficient and effective data sharing still faces several hurdles. For example, open data sharing is on the rise but is not suitable for sensitive data that are not easily shared, such as genetics. Current approaches can be cumbersome (such as negotiating multiple data sharing agreements). There are also significant data transfer, organization and computational challenges. Centralized repositories only partially address the issues. We propose a dynamic, decentralized platform for large scale analyses called the Collaborative Informatics and Neuroimaging Suite Toolkit for Anonymous Computation (COINSTAC). The COINSTAC solution can include data missing from central repositories, allows pooling of both open and "closed" repositories by developing privacy-preserving versions of widely-used algorithms, and incorporates the tools within an easy-to-use platform enabling distributed computation. We present an initial prototype system which we demonstrate on two multi-site data sets, without aggregating the data. In addition, by iterating across sites, the COINSTAC model enables meta-analytic solutions to converge to "pooled-data" solutions (i.e., as if the entire data were in hand). More advanced approaches such as feature generation, matrix factorization models, and preprocessing can be incorporated into such a model. In sum, COINSTAC enables access to the many currently unavailable data sets, a user friendly privacy enabled interface for decentralized analysis, and a powerful solution that complements existing data sharing solutions.

COINSTAC: A Privacy Enabled Model and Prototype for Leveraging and Processing Decentralized Brain Imaging Data

PubMed Central

Plis, Sergey M.; Sarwate, Anand D.; Wood, Dylan; Dieringer, Christopher; Landis, Drew; Reed, Cory; Panta, Sandeep R.; Turner, Jessica A.; Shoemaker, Jody M.; Carter, Kim W.; Thompson, Paul; Hutchison, Kent; Calhoun, Vince D.

2016-01-01

The field of neuroimaging has embraced the need for sharing and collaboration. Data sharing mandates from public funding agencies and major journal publishers have spurred the development of data repositories and neuroinformatics consortia. However, efficient and effective data sharing still faces several hurdles. For example, open data sharing is on the rise but is not suitable for sensitive data that are not easily shared, such as genetics. Current approaches can be cumbersome (such as negotiating multiple data sharing agreements). There are also significant data transfer, organization and computational challenges. Centralized repositories only partially address the issues. We propose a dynamic, decentralized platform for large scale analyses called the Collaborative Informatics and Neuroimaging Suite Toolkit for Anonymous Computation (COINSTAC). The COINSTAC solution can include data missing from central repositories, allows pooling of both open and “closed” repositories by developing privacy-preserving versions of widely-used algorithms, and incorporates the tools within an easy-to-use platform enabling distributed computation. We present an initial prototype system which we demonstrate on two multi-site data sets, without aggregating the data. In addition, by iterating across sites, the COINSTAC model enables meta-analytic solutions to converge to “pooled-data” solutions (i.e., as if the entire data were in hand). More advanced approaches such as feature generation, matrix factorization models, and preprocessing can be incorporated into such a model. In sum, COINSTAC enables access to the many currently unavailable data sets, a user friendly privacy enabled interface for decentralized analysis, and a powerful solution that complements existing data sharing solutions. PMID:27594820

Decentralization or centralization: striking a balance.

PubMed

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.

A Comparative Analysis of Factors Related to a Candidate's Success or Failure in the 1975 and 1977 Community School Board Elections in New York City.

ERIC Educational Resources Information Center

Levine, Jonathan; Clawar, Harry J.

In 1960, the New York City Public School System was decentralized into 32 school districts with limited authority over elementary and junior high schools. Locally elected district community school boards were provided for by State legislation. In this study factors relevant to predicting a candidate's success or failure in the 1975 and 1977 school…

Decentralized supply chain network design: monopoly, duopoly and oligopoly competitions under uncertainty

NASA Astrophysics Data System (ADS)

Seyedhosseini, Seyed Mohammad; Fahimi, Kaveh; Makui, Ahmad

2017-12-01

This paper presents the competitive supply chain network design problem in which n decentralized supply chains simultaneously enter the market with no existing rival chain, shape their networks and set wholesale and retail prices in competitive mode. The customer demand is elastic and price dependent, customer utility function is based on the Hoteling model and the chains produce identical or highly substitutable products. We construct a solution algorithm based on bi-level programming and possibility theory. In the proposed bi-level model, the inner part sets the prices based on simultaneous extra- and Stackleberg intra- chains competitions, and the outer part shapes the networks in cooperative competitions. Finally, we use a real-word study to discuss the effect of the different structures of the competitors on the equilibrium solution. Moreover, sensitivity analyses are conducted and managerial insights are offered.

Distributed Method to Optimal Profile Descent

NASA Astrophysics Data System (ADS)

Kim, Geun I.

Current ground automation tools for Optimal Profile Descent (OPD) procedures utilize path stretching and speed profile change to maintain proper merging and spacing requirements at high traffic terminal area. However, low predictability of aircraft's vertical profile and path deviation during decent add uncertainty to computing estimated time of arrival, a key information that enables the ground control center to manage airspace traffic effectively. This paper uses an OPD procedure that is based on a constant flight path angle to increase the predictability of the vertical profile and defines an OPD optimization problem that uses both path stretching and speed profile change while largely maintaining the original OPD procedure. This problem minimizes the cumulative cost of performing OPD procedures for a group of aircraft by assigning a time cost function to each aircraft and a separation cost function to a pair of aircraft. The OPD optimization problem is then solved in a decentralized manner using dual decomposition techniques under inter-aircraft ADS-B mechanism. This method divides the optimization problem into more manageable sub-problems which are then distributed to the group of aircraft. Each aircraft solves its assigned sub-problem and communicate the solutions to other aircraft in an iterative process until an optimal solution is achieved thus decentralizing the computation of the optimization problem.

Strengthening decentralized primary healthcare planning in Nigeria using a quality improvement model: how contexts and actors affect implementation.

PubMed

Eboreime, Ejemai Amaize; Nxumalo, Nonhlanhla; Ramaswamy, Rohit; Eyles, John

2018-05-08

Quality improvement models have been applied across various levels of health systems with varying success leading to scepticisms about effectiveness. Health systems are complex, influenced by contexts and characterized by numerous interests. Thus, a shift in focus from examining whether improvement models work, to understanding why, when and where they work most effectively is essential. Nigeria introduced DIVA (Diagnose-Intervene-Verify-Adjust) as a model to strengthen decentralized PHC planning. However, implementation has been poorly sustained. This article explores the role of actors and context in implementation and sustainability of DIVA in two local government areas (LGAs) in Nigeria. We employed an integrated mixed method approach in which qualitative data was used in conjunction with quantitative to understand effects of actors and contexts on implementation outcomes. We analysed policy documents and conducted interviews with PHC managers. Then using the Model for Understanding Success in Quality (MUSIQ), we measured contextual factors affecting implementation of DIVA in the selected LGAs. The LGAs scored 117.42 and 104.67 out of 168 points on the MUSIQ scale, respectively, indicating contextual barriers exist. Both have strong DIVA team attributes, but these could not independently ensure quality implementation. Although external support accounted for the greatest contextual disparities, the utmost implementation challenges relate to subnational government leadership, management, financial and technical support. Although higher levels of government may set visionary goals for PHC, interventions are potentially skewed towards donor interests at lower (implementation) levels. Thus, subnational political will is a key determinant of quality implementation. Consequently, advocacy for responsible and accountable political governance is essential in comparable decentralized contexts.

The Paradox of Decentralizing Schools: Lessons from Business, Government, and the Catholic Church.

ERIC Educational Resources Information Center

Murphy, Jerome T.

1989-01-01

By the year 2000, school decentralization could become another unfortunate, ineffectual pendulum swing. According to this article, a dynamic, ever-changing system of decentralization and centralization balances the benefits of local administrative autonomy with the pursuit of unified goals and helps each leadership level understand its…

On Deciding How to Decide: To Centralize or Decentralize.

ERIC Educational Resources Information Center

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…

Centralization Versus Decentralization: A Location Analysis Approach for Librarians.

ERIC Educational Resources Information Center

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…

Effects of Decentralization on School Resources

ERIC Educational Resources Information Center

Ahlin, Asa; Mork, Eva

2008-01-01

Sweden has undertaken major national reforms of its school sector, which, consequently, has been classified as one of the most decentralized ones in the OECD. This paper investigates whether local tax base, grants, and preferences affected local school resources differently as decentralization took place. We find that municipal tax base affects…

Responsibility Center Management: Lessons from 25 Years of Decentralized Management.

ERIC Educational Resources Information Center

Strauss, Jon C.; Curry, John R.

Decentralization of authority is a natural act in universities, but decentralization of responsibility is not. A problem faced by universities is the decoupling of academic authority from financial responsibility. The solution proposed in this book for the coupling is Responsibility Center Management (RCM), also called Revenue Responsibility…

A Review of Characteristics and Experiences of Decentralization of Education

ERIC Educational Resources Information Center

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…

40 CFR 51.353 - Network type and program evaluation.

Code of Federal Regulations, 2013 CFR

2013-07-01

..., decentralized, or a hybrid of the two at the State's discretion, but shall be demonstrated to achieve the same... § 51.351 or 51.352 of this subpart. For decentralized programs other than those meeting the design.... (a) Presumptive equivalency. A decentralized network consisting of stations that only perform...

On l(1): Optimal decentralized performance

NASA Technical Reports Server (NTRS)

Sourlas, Dennis; Manousiouthakis, Vasilios

1993-01-01

In this paper, the Manousiouthakis parametrization of all decentralized stabilizing controllers is employed in mathematically formulating the l(sup 1) optimal decentralized controller synthesis problem. The resulting optimization problem is infinite dimensional and therefore not directly amenable to computations. It is shown that finite dimensional optimization problems that have value arbitrarily close to the infinite dimensional one can be constructed. Based on this result, an algorithm that solves the l(sup 1) decentralized performance problems is presented. A global optimization approach to the solution of the infinite dimensional approximating problems is also discussed.

Survey of decentralized control methods. [for large scale dynamic systems

NASA Technical Reports Server (NTRS)

Athans, M.

1975-01-01

An overview is presented of the types of problems that are being considered by control theorists in the area of dynamic large scale systems with emphasis on decentralized control strategies. Approaches that deal directly with decentralized decision making for large scale systems are discussed. It is shown that future advances in decentralized system theory are intimately connected with advances in the stochastic control problem with nonclassical information pattern. The basic assumptions and mathematical tools associated with the latter are summarized, and recommendations concerning future research are presented.

Formation Flying With Decentralized Control in Libration Point Orbits

NASA Technical Reports Server (NTRS)

Folta, David; Carpenter, J. Russell; Wagner, Christoph

2000-01-01

A decentralized control framework is investigated for applicability of formation flying control in libration orbits. The decentralized approach, being non-hierarchical, processes only direct measurement data, in parallel with the other spacecraft. Control is accomplished via linearization about a reference libration orbit with standard control using a Linear Quadratic Regulator (LQR) or the GSFC control algorithm. Both are linearized about the current state estimate as with the extended Kalman filter. Based on this preliminary work, the decentralized approach appears to be feasible for upcoming libration missions using distributed spacecraft.

Organizational decentralization in radiology.

PubMed

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.

DSSTOX WEBSITE LAUNCH: IMPROVING PUBLIC ACCESS ...

EPA Pesticide Factsheets

DSSTox Website Launch: Improving Public Access to Databases for Building Structure-Toxicity Prediction ModelsAnn M. RichardUS Environmental Protection Agency, Research Triangle Park, NC, USADistributed: Decentralized set of standardized, field-delimited databases, each separatelyauthored and maintained, that are able to accommodate diverse toxicity data content;Structure-Searchable: Standard format (SDF) structure-data files that can be readily imported into available chemical relational databases and structure-searched;Tox: Toxicity data as it exists in widely disparate forms in current public databases, spanning diverse toxicity endpoints, test systems, levels of biological content, degrees of summarization, and information content.INTRODUCTIONThe economic and social pressures to reduce the need for animal testing and to better anticipate the potential for human and eco-toxicity of environmental, industrial, or pharmaceutical chemicals are as pressing today as at any time prior. However, the goal of predicting chemical toxicity in its many manifestations, the `T' in 'ADMET' (adsorption, distribution, metabolism, elimination, toxicity), remains one of the most difficult and largely unmet challenges in a chemical screening paradigm [1]. It is widely acknowledged that the single greatest hurdle to improving structure-activity relationship (SAR) toxicity prediction capabilities, in both the pharmaceutical and environmental regulation arenas, is the lack of suffici

Integrated Decentralized Training for Health Professions Education at the University of KwaZulu-Natal, South Africa: Protocol for the I-DecT Project.

PubMed

Govender, Pragashnie; Chetty, Verusia; Naidoo, Deshini; Pefile, Ntsikelelo

2018-01-25

The Integrated Decentralized Training (i-DecT) project was created to address the current need for health care in South Africa among resource poor climates in rural and periurban settings. The University of KwaZulu-Natal (UKZN) in South Africa has embarked on a program within the School of Health Sciences (SHS) to decentralize the clinical learning platform in order to address this disparity. Framed in a pragmatic stance, this proposal is geared towards informing the roll out of decentralized clinical training (DCT) within the province of KwaZulu-Natal. There currently remains uncertainty as to how the implementation of this program will unfold, especially for the diverse SHS, which includes specialities like audiology, dentistry, occupational therapy, optometry, pharmacy, physiotherapy, speech-language pathology, and sport science. Consequently, there is a need to carefully monitor and manage this DCT in order to ensure that the participating students have a positive learning experience and achieve expected academic outcomes, and that the needs of the communities are addressed adequately. The study aims to explore the factors that will influence the roll-out of the DCT by developing an inclusive and context-specific model that will adhere to the standards set by the SHS for the DCT program at UKZN. Key role players, including but not limited to, the South African Ministry of Health policy makers, clinicians, policy makers at UKZN, clinical educators, academicians, and students of UKZN within the SHS will participate in this project. Once the infrastructural, staffing and pedagogical enablers and challenges are identified, together with a review of existing models of decentralized training, a context-specific model for DCTl will be proposed based on initial pilot data that will be tested within iterative cycles in an Action Learning Action Research (ALAR) process. The study was designed to fit within the existing structures, and emerging framework and memorandum of understanding between the partners of this initiative, namely, the Ministry of Health and UKZN in order to develop health care professionals that are competent and prepared for the changing dynamics of healthcare in a developing world. It is envisioned that this study, the first to include a combination of health professionals in a DCT platform at UKZN, will not only contribute to effective service delivery, but may also serve to promote an interprofessional cooperation within the SHS and tertiary institutions in similar settings. ©Pragashnie Govender, Verusia Chetty, Deshini Naidoo, Ntsikelelo Pefile. Originally published in JMIR Research Protocols (http://www.researchprotocols.org), 25.01.2018.

Integration of a Decentralized Linear-Quadratic-Gaussian Control into GSFC's Universal 3-D Autonomous Formation Flying Algorithm

NASA Technical Reports Server (NTRS)

Folta, David C.; Carpenter, J. Russell

1999-01-01

A decentralized control is investigated for applicability to the autonomous formation flying control algorithm developed by GSFC for the New Millenium Program Earth Observer-1 (EO-1) mission. This decentralized framework has the following characteristics: The approach is non-hierarchical, and coordination by a central supervisor is not required; Detected failures degrade the system performance gracefully; Each node in the decentralized network processes only its own measurement data, in parallel with the other nodes; Although the total computational burden over the entire network is greater than it would be for a single, centralized controller, fewer computations are required locally at each node; Requirements for data transmission between nodes are limited to only the dimension of the control vector, at the cost of maintaining a local additional data vector. The data vector compresses all past measurement history from all the nodes into a single vector of the dimension of the state; and The approach is optimal with respect to standard cost functions. The current approach is valid for linear time-invariant systems only. Similar to the GSFC formation flying algorithm, the extension to linear LQG time-varying systems requires that each node propagate its filter covariance forward (navigation) and controller Riccati matrix backward (guidance) at each time step. Extension of the GSFC algorithm to non-linear systems can also be accomplished via linearization about a reference trajectory in the standard fashion, or linearization about the current state estimate as with the extended Kalman filter. To investigate the feasibility of the decentralized integration with the GSFC algorithm, an existing centralized LQG design for a single spacecraft orbit control problem is adapted to the decentralized framework while using the GSFC algorithm's state transition matrices and framework. The existing GSFC design uses both reference trajectories of each spacecraft in formation and by appropriate choice of coordinates and simplified measurement modeling is formulated as a linear time-invariant system. Results for improvements to the GSFC algorithm and a multiple satellite formation will be addressed. The goal of this investigation is to progressively relax the assumptions that result in linear time-invariance, ultimately to the point of linearization of the non-linear dynamics about the current state estimate as in the extended Kalman filter. An assessment will then be made about the feasibility of the decentralized approach to the realistic formation flying application of the EO-1/Landsat 7 formation flying experiment.

The Traditional Centralized Model of Institutional Research: Its Derivation & Evolution at One College.

ERIC Educational Resources Information Center

Slark, Julie

A description is provided of Rancho Santiago College's institutional research program, which uses a traditional centralized research model, augmented with alternative, decentralized approaches. First, background information is presented on the college and the role of the research office in management, decision-making, and educational support.…

Reconnecting: A Phenomenological Study of Transition within a Shared Model of Academic Advising

ERIC Educational Resources Information Center

Barker, Shane; Mamiseishvili, Ketevan

2014-01-01

This study explored students' experiences of transition from centralized, professional advising to decentralized, faculty-based advising within a shared advising model at a public research university. Data were collected via focus groups and interviews from 17 participants and examined using phenomenological analysis. Four fundamental themes were…

A new framework for modeling decentralized low impact developments using Soil and Water Assessment Tool

USDA-ARS?s Scientific Manuscript database

Assessing the performance of Low Impact Development (LID) practices at a catchment scale is important in managing urban watersheds. Few modeling tools exist that are capable of explicitly representing the hydrological mechanisms of LIDs while considering the diverse land uses of urban watersheds. ...

An Example of Decentralized Management in Education: Provincial Directory Model

ERIC Educational Resources Information Center

Ada, Sefer; Baysal, Z. Nurdan; Erkan, Senem Seda Sahenk

2016-01-01

In Turkey, two types of administrative structures existed in the fields of National Education: "the central" and "provincial" institutions. However, between 1926-1931, the Locality model was implemented. Locality can be considered as a local administration formed in the provincial organization of the Ministry of Education by…

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Walters, Terri; Rai, Neha; Esterly, Sean

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 establishingmore » 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.« less

The evolution of the federal funding policies for the public health surveillance component of Brazil's Unified Health System (SUS).

PubMed

Pinto, Vitor Laerte; Cerbino Neto, José; Penna, Gerson Oliveira

2014-12-01

Health surveillance (HS) is one of the key components of the Brazilian Unified Health System (SUS). This article describes recent changes in health surveillance funding models and the role these changes have had in the reorganization and decentralization of health actions. Federal law no. 8.080 of 1990 defined health surveillance as a fundamental pillar of the SUS, and an exclusive fund with equitable distribution criteria was created in the Basic Operational Norm of 1996 to pay for health surveillance actions. This step facilitated the decentralization of health care at the municipal level, giving local authorities autonomy to plan and provide services. The Health Pact of 2006 and its regulation under federal decree No. 3252 in 2009 bolstered the processes of decentralization, regionalization and integration of health care. Further changes in the basic concepts of health surveillance around the world and in the funding policies negotiated by different spheres of government in Brazil have been catalysts for the process of HS institutionalization in recent years.

Centralization and Decentralization: An International Viewpoint on an American Dilemma. A Special CASEA Report.

ERIC Educational Resources Information Center

Walker, William G.

This report outlines the history of the centralization-decentralization dilemma in the goverance of organizations, discusses two types of centralization-decentralization continua, and suggests further research. The first type of continuum discussed -- the traditional American -- refers to decisionmaking in the areas of public debate and partisan…

Providing leadership to a decentralized total quality process.

PubMed

Diederich, J J; Eisenberg, M

1993-01-01

Integrating total quality management into the culture of an organization and the daily work of employees requires a decentralized leadership structure that encourages all employees to become involved. This article, based upon the experience of the University of Michigan Hospitals Professional Services Divisional Lead Team, outlines a process for decentralizing the total quality management process.

The Effect of Political Decentralization on School Leadership in German Vocational Schools

ERIC Educational Resources Information Center

Gessler, Michael; Ashmawy, Iman K.

2016-01-01

In this explorative qualitative study the effect of political decentralization on vocational school leadership is investigated. Through conducting structural interviews with 15 school principals in the states of Bremen and Lower Saxony in Germany, the study was able to conclude that political decentralization entails the creation of elected bodies…

Institutional v. Technical Environments: Reconciling the Goals of Decentralization in an Evolving Charter School Organization

ERIC Educational Resources Information Center

Huerta, Luis A.

2009-01-01

This article analyzes how macrolevel institutional forces persist and limit the expansion of decentralized schools that attempt to challenge normative definitions and practices of traditional school organizations. Using qualitative case study methodology, the analysis focuses on how one decentralized charter school navigated and reconciled its…

After Decentralization: Delimitations and Possibilities within New Fields

ERIC Educational Resources Information Center

Wahlstrom, Ninni

2008-01-01

The shift from a centralized to a decentralized school system can be seen as a solution to an uncertain problem. Through analysing the displacements in the concept of equivalence within Sweden's decentralized school system, this study illustrates how the meaning of the concept of equivalence shifts over time, from a more collective target…

Decentralization of Education in Indonesia--A Study on Education Development Gaps in the Provincial Areas

ERIC Educational Resources Information Center

Winardi

2017-01-01

Decentralization is acknowledged as the handover of government from central government to local government, including giving broader authority to local governments to manage education. This study aims to discovering education development gap between regions in Indonesia as a result of decentralization. This research method uses descriptive…

The Role of Political, Educational, and Community Leaders in the Decentralization of Education in Pakistan

ERIC Educational Resources Information Center

Nasrullah

2016-01-01

The roles of educational, political, and community leaders in the decentralization of education in Khyber Pakhtunkhwa (KPK) province of Pakistan were explored in this phenomenological research. Examined were leaders' perceptions and understandings of decentralization and its effects on teacher instructional practices, process of student learning,…

Decentralization in Education: Technical Demands as a Critical Ingredient.

ERIC Educational Resources Information Center

Hannaway, Jane

The implications of decentralization reform on the amount of serious attention and effort that teachers give to teaching and learning activities are explored in this paper. The discussion is informed by the results of two case studies of school districts recognized as exemplary cases of decentralization. The first section describes limitations of…

The rise of governmentality in the Italian National Health System: physiology or pathology of a decentralized and (ongoing) federalist system?

PubMed

Lega, Federico; Sargiacomo, Massimo; Ianni, Luca

2010-11-01

In this paper, we aim to discuss the implications and lessons that can be learnt from the ongoing process of federalism affecting the Italian National Health System (INHS). Many countries are currently taking decisions concerning the decentralization or re-centralization of their health-care systems, with several key issues that are illustrated in the recent history of the INHS. The decentralization process of INHS has produced mixed results, as some regions took advantage of it to strengthen their systems, whereas others were not capable of developing an effective steering role. We argue that the mutual reinforcement of the decentralization and recentralization processes is not paradoxical, but is actually an effective way for the State to maintain control over the equity and efficiency of its health-care system while decentralizing at a regional level. In this perspective, we provide evidence backing up some of the assumptions made in previous works as well as new food-for thought - specifically on how governmentality and federalism should meet - to reshape the debate on decentralization in health care.

Adaptive neural network decentralized backstepping output-feedback control for nonlinear large-scale systems with time delays.

PubMed

Tong, Shao Cheng; Li, Yong Ming; Zhang, Hua-Guang

2011-07-01

In this paper, two adaptive neural network (NN) decentralized output feedback control approaches are proposed for a class of uncertain nonlinear large-scale systems with immeasurable states and unknown time delays. Using NNs to approximate the unknown nonlinear functions, an NN state observer is designed to estimate the immeasurable states. By combining the adaptive backstepping technique with decentralized control design principle, an adaptive NN decentralized output feedback control approach is developed. In order to overcome the problem of "explosion of complexity" inherent in the proposed control approach, the dynamic surface control (DSC) technique is introduced into the first adaptive NN decentralized control scheme, and a simplified adaptive NN decentralized output feedback DSC approach is developed. It is proved that the two proposed control approaches can guarantee that all the signals of the closed-loop system are semi-globally uniformly ultimately bounded, and the observer errors and the tracking errors converge to a small neighborhood of the origin. Simulation results are provided to show the effectiveness of the proposed approaches.

The effect of social influence on cognitive development and school performance.

PubMed

Hartmann, E; Eri, T J; Skinstad, A H

1989-01-01

Three months before school entrance a sample of 29 children and their mothers was tested for degree of decentred child educability and degree of decentred maternal teaching. Mother and child were tested in two different situations, thus preventing interdependency between the measures of mother and child. Four months after school entrance, teacher judgements of school performance were obtained. A strong correspondence between degree of decentred child educability and degree of decentred maternal teaching was demonstrated. Degree of decentred maternal teaching and degree of decentred child educability were found to be good predictors of school performance, accounting for respectively 45 and 33% of the variance in school performance. In contrast a test of school readiness only accounted for 2% of the variance. A test of intelligence given after the teacher judgement accounted for 31% of the variance. The fact that the mother seems to be a better predictor of her child's school performance than the child himself, supports the assumption that parents, particularly mothers, are important mediators between the child and the outer world.

SPHERES tethered formation flight testbed: application to NASA's SPECS mission

NASA Astrophysics Data System (ADS)

Chung, Soon-Jo; Kong, Edmund M.; Miller, David W.

2005-08-01

This paper elaborates on theory and experiment of the formation flight control for the future space-borne tethered interferometers. The nonlinear equations of multi-vehicle tethered spacecraft system are derived by Lagrange equations and decoupling method. The preliminary analysis predicts unstable dynamics depending on the direction of the tether motor. The controllability analysis indicates that both array resizing and spin-up are fully controllable only by the reaction wheels and the tether motor, thereby eliminating the need for thrusters. Linear and nonlinear decentralized control techniques have been implemented into the tethered SPHERES testbed, and tested at the NASA MSFC's flat floor facility using two and three SPHERES configurations. The nonlinear control using feedback linearization technique performed successfully in both two SPHERES in-line configuration and three triangular configuration while varying the tether length. The relative metrology system, using the ultra sound metrology system and the inertial sensors as well as the decentralized nonlinear estimator, is developed to provide necessary state information.

Decentralized Online Social Networks

NASA Astrophysics Data System (ADS)

Datta, Anwitaman; Buchegger, Sonja; Vu, Le-Hung; Strufe, Thorsten; Rzadca, Krzysztof

Current Online social networks (OSN) are web services run on logically centralized infrastructure. Large OSN sites use content distribution networks and thus distribute some of the load by caching for performance reasons, nevertheless there is a central repository for user and application data. This centralized nature of OSNs has several drawbacks including scalability, privacy, dependence on a provider, need for being online for every transaction, and a lack of locality. There have thus been several efforts toward decentralizing OSNs while retaining the functionalities offered by centralized OSNs. A decentralized online social network (DOSN) is a distributed system for social networking with no or limited dependency on any dedicated central infrastructure. In this chapter we explore the various motivations of a decentralized approach to online social networking, discuss several concrete proposals and types of DOSN as well as challenges and opportunities associated with decentralization.

Decentralization's impact on the health workforce: Perspectives of managers, workers and national leaders

PubMed Central

Kolehmainen-Aitken, Riitta-Liisa

2004-01-01

Designers and implementers of decentralization and other reform measures have focused much attention on financial and structural reform measures, but ignored their human resource implications. Concern is mounting about the impact that the reallocation of roles and responsibilities has had on the health workforce and its management, but the experiences and lessons of different countries have not been widely shared. This paper examines evidence from published literature on decentralization's impact on the demand side of the human resource equation, as well as the factors that have contributed to the impact. The elements that make such an impact analysis exceptionally complex are identified. They include the mode of decentralization that a country is implementing, the level of responsibility for the salary budget and pay determination, and the civil service status of transferred health workers. The main body of the paper is devoted to examining decentralization's impact on human resource issues from three different perspectives: that of local health managers, health workers themselves, and national health leaders. These three groups have different concerns in the human resource realm, and consequently, have been differently affected by decentralization processes. The paper concludes with recommendations regarding three key concerns that national authorities and international agencies should give prompt attention to. They are (1) defining the essential human resource policy, planning and management skills for national human resource managers who work in decentralized countries, and developing training programs to equip them with such skills; (2) supporting research that focuses on improving the knowledge base of how different modes of decentralization impact on staffing equity; and (3) identifying factors that most critically influence health worker motivation and performance under decentralization, and documenting the most cost-effective best practices to improve them. Notable experiences from South Africa, Ghana, Indonesia and Mexico are shared in an annex. PMID:15144558

A decentralized mechanism for improving the functional robustness of distribution networks.

PubMed

Shi, Benyun; Liu, Jiming

2012-10-01

Most real-world distribution systems can be modeled as distribution networks, where a commodity can flow from source nodes to sink nodes through junction nodes. One of the fundamental characteristics of distribution networks is the functional robustness, which reflects the ability of maintaining its function in the face of internal or external disruptions. In view of the fact that most distribution networks do not have any centralized control mechanisms, we consider the problem of how to improve the functional robustness in a decentralized way. To achieve this goal, we study two important problems: 1) how to formally measure the functional robustness, and 2) how to improve the functional robustness of a network based on the local interaction of its nodes. First, we derive a utility function in terms of network entropy to characterize the functional robustness of a distribution network. Second, we propose a decentralized network pricing mechanism, where each node need only communicate with its distribution neighbors by sending a "price" signal to its upstream neighbors and receiving "price" signals from its downstream neighbors. By doing so, each node can determine its outflows by maximizing its own payoff function. Our mathematical analysis shows that the decentralized pricing mechanism can produce results equivalent to those of an ideal centralized maximization with complete information. Finally, to demonstrate the properties of our mechanism, we carry out a case study on the U.S. natural gas distribution network. The results validate the convergence and effectiveness of our mechanism when comparing it with an existing algorithm.

A Decentralized Event-Triggered Dissipative Control Scheme for Systems With Multiple Sensors to Sample the System Outputs.

PubMed

Zhang, Xian-Ming; Han, Qing-Long

2016-12-01

This paper is concerned with decentralized event-triggered dissipative control for systems with the entries of the system outputs having different physical properties. Depending on these different physical properties, the entries of the system outputs are grouped into multiple nodes. A number of sensors are used to sample the signals from different nodes. A decentralized event-triggering scheme is introduced to select those necessary sampled-data packets to be transmitted so that communication resources can be saved significantly while preserving the prescribed closed-loop performance. First, in order to organize the decentralized data packets transmitted from the sensor nodes, a data packet processor (DPP) is used to generate a new signal to be held by the zero-order-hold once the signal stored by the DPP is updated at some time instant. Second, under the mechanism of the DPP, the resulting closed-loop system is modeled as a linear system with an interval time-varying delay. A sufficient condition is derived such that the closed-loop system is asymptotically stable and strictly (Q 0 ,S 0 ,R 0 ) -dissipative, where Q 0 ,S 0 , and R 0 are real matrices of appropriate dimensions with Q 0 and R 0 symmetric. Third, suitable output-based controllers can be designed based on solutions to a set of a linear matrix inequality. Finally, two examples are given to demonstrate the effectiveness of the proposed method.

Case mix management education in a Canadian hospital.

PubMed

Moffat, M; Prociw, M

1992-01-01

The Sunnybrook Health Science Centre's matrix organization model includes a traditional departmental structure, a strategic program-based structure and a case management-based structure--the Clinical Unit structure. The Clinical Unit structure allows the centre to give responsibility for the management of case mix and volume to decentralized Clinical Unit teams, each of which manages its own budget. To train physicians and nurses in their respective roles of Medical Unit directors and Nursing Unit directors, Sunnybrook designed unique short courses on financial management and budgeting, and case-costing and case mix management. This paper discusses how these courses were organized, details their contents and explains how they fit into Sunnybrook's program of decentralized management.

Mode identification using stochastic hybrid models with applications to conflict detection and resolution

NASA Astrophysics Data System (ADS)

Naseri Kouzehgarani, Asal

2009-12-01

Most models of aircraft trajectories are non-linear and stochastic in nature; and their internal parameters are often poorly defined. The ability to model, simulate and analyze realistic air traffic management conflict detection scenarios in a scalable, composable, multi-aircraft fashion is an extremely difficult endeavor. Accurate techniques for aircraft mode detection are critical in order to enable the precise projection of aircraft conflicts, and for the enactment of altitude separation resolution strategies. Conflict detection is an inherently probabilistic endeavor; our ability to detect conflicts in a timely and accurate manner over a fixed time horizon is traded off against the increased human workload created by false alarms---that is, situations that would not develop into an actual conflict, or would resolve naturally in the appropriate time horizon-thereby introducing a measure of probabilistic uncertainty in any decision aid fashioned to assist air traffic controllers. The interaction of the continuous dynamics of the aircraft, used for prediction purposes, with the discrete conflict detection logic gives rise to the hybrid nature of the overall system. The introduction of the probabilistic element, common to decision alerting and aiding devices, places the conflict detection and resolution problem in the domain of probabilistic hybrid phenomena. A hidden Markov model (HMM) has two stochastic components: a finite-state Markov chain and a finite set of output probability distributions. In other words an unobservable stochastic process (hidden) that can only be observed through another set of stochastic processes that generate the sequence of observations. The problem of self separation in distributed air traffic management reduces to the ability of aircraft to communicate state information to neighboring aircraft, as well as model the evolution of aircraft trajectories between communications, in the presence of probabilistic uncertain dynamics as well as partially observable and uncertain data. We introduce the Hybrid Hidden Markov Modeling (HHMM) formalism to enable the prediction of the stochastic aircraft states (and thus, potential conflicts), by combining elements of the probabilistic timed input output automaton and the partially observable Markov decision process frameworks, along with the novel addition of a Markovian scheduler to remove the non-deterministic elements arising from the enabling of several actions simultaneously. Comparisons of aircraft in level, climbing/descending and turning flight are performed, and unknown flight track data is evaluated probabilistically against the tuned model in order to assess the effectiveness of the model in detecting the switch between multiple flight modes for a given aircraft. This also allows for the generation of probabilistic distribution over the execution traces of the hybrid hidden Markov model, which then enables the prediction of the states of aircraft based on partially observable and uncertain data. Based on the composition properties of the HHMM, we study a decentralized air traffic system where aircraft are moving along streams and can perform cruise, accelerate, climb and turn maneuvers. We develop a common decentralized policy for conflict avoidance with spatially distributed agents (aircraft in the sky) and assure its safety properties via correctness proofs.

Cost-effectiveness of two operational models at industrial wastewater treatment plants in China: a case study in Shengze town, Suzhou City.

PubMed

Yuan, Zengwei; Jiang, Weili; Bi, Jun

2010-10-01

The widespread illegal discharge of industrial wastewater in China has posed significant challenges to the effective management of industrial wastewater treatment plants (IWTPs) and caused or exacerbated critical social issues such as trans-boundary environmental pollution. This study examines two operational strategies, decentralized model and an innovative integrated model, that have been used in the industrial town of Shengze (located in Suzhou City) over the past two decades at IWTPs handling wastewater from the city's dyeing industry. Our cost-effectiveness analysis shows that, although the operational cost of IWTPs under the integrated model is higher than under the original decentralized model, the integrated model has significantly improved IWTP performance and effectively reduced illegal discharge of industrial wastewater. As a result, the number of reported incidents of unacceptable pollution in local receiving water bodies had declined from 13 in 2000-1 in 2008. Key factors contributing to the success of the innovative integrated model are strong support from municipal and provincial leaders, mandatory ownership transfer of IWTPs to a centralized management body, strong financial incentives for proper plant management, and geographically-clustered IWTPs. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Value Driven Information Processing and Fusion

DTIC Science & Technology

2016-03-01

consensus approach allows a decentralized approach to achieve the optimal error exponent of the centralized counterpart, a conclusion that is signifi...SECURITY CLASSIFICATION OF: The objective of the project is to develop a general framework for value driven decentralized information processing...including: optimal data reduction in a network setting for decentralized inference with quantization constraint; interactive fusion that allows queries and

A Summary of Some Discrete-Event System Control Problems

NASA Astrophysics Data System (ADS)

Rudie, Karen

A summary of the area of control of discrete-event systems is given. In this research area, automata and formal language theory is used as a tool to model physical problems that arise in technological and industrial systems. The key ingredients to discrete-event control problems are a process that can be modeled by an automaton, events in that process that cannot be disabled or prevented from occurring, and a controlling agent that manipulates the events that can be disabled to guarantee that the process under control either generates all the strings in some prescribed language or as many strings as possible in some prescribed language. When multiple controlling agents act on a process, decentralized control problems arise. In decentralized discrete-event systems, it is presumed that the agents effecting control cannot each see all event occurrences. Partial observation leads to some problems that cannot be solved in polynomial time and some others that are not even decidable.

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

NASA Astrophysics Data System (ADS)

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.

Driving Parameters for Distributed and Centralized Air Transportation Architectures

NASA Technical Reports Server (NTRS)

Feron, Eric

2001-01-01

This report considers the problem of intersecting aircraft flows under decentralized conflict avoidance rules. Using an Eulerian standpoint (aircraft flow through a fixed control volume), new air traffic control models and scenarios are defined that enable the study of long-term airspace stability problems. Considering a class of two intersecting aircraft flows, it is shown that airspace stability, defined both in terms of safety and performance, is preserved under decentralized conflict resolution algorithms. Performance bounds are derived for the aircraft flow problem under different maneuver models. Besides analytical approaches, numerical examples are presented to test the theoretical results, as well as to generate some insight about the structure of the traffic flow after resolution. Considering more than two intersecting aircraft flows, simulations indicate that flow stability may not be guaranteed under simple conflict avoidance rules. Finally, a comparison is made with centralized strategies to conflict resolution.

Robust decentralized controller for minimizing coupling effect in single inductor multiple output DC-DC converter operating in continuous conduction mode.

PubMed

Medeiros, Renan Landau Paiva de; Barra, Walter; Bessa, Iury Valente de; Chaves Filho, João Edgar; Ayres, Florindo Antonio de Cavalho; Neves, Cleonor Crescêncio das

2018-02-01

This paper describes a novel robust decentralized control design methodology for a single inductor multiple output (SIMO) DC-DC converter. Based on a nominal multiple input multiple output (MIMO) plant model and performance requirements, a pairing input-output analysis is performed to select the suitable input to control each output aiming to attenuate the loop coupling. Thus, the plant uncertainty limits are selected and expressed in interval form with parameter values of the plant model. A single inductor dual output (SIDO) DC-DC buck converter board is developed for experimental tests. The experimental results show that the proposed methodology can maintain a desirable performance even in the presence of parametric uncertainties. Furthermore, the performance indexes calculated from experimental data show that the proposed methodology outperforms classical MIMO control techniques. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

Brief Report: Decentralizing ART Supply for Stable HIV Patients to Community-Based Distribution Centers: Program Outcomes From an Urban Context in Kinshasa, DRC.

PubMed

Vogt, Florian; Kalenga, Lucien; Lukela, Jean; Salumu, Freddy; Diallo, Ibrahim; Nico, Elena; Lampart, Emmanuel; Van den Bergh, Rafael; Shah, Safieh; Ogundahunsi, Olumide; Zachariah, Rony; Van Griensven, Johan

2017-03-01

Facility-based antiretroviral therapy (ART) provision for stable patients with HIV congests health services in resource-limited countries. We assessed outcomes and risk factors for attrition after decentralization to community-based ART refill centers among 2603 patients with HIV in Kinshasa, Democratic Republic of Congo, using a multilevel Poisson regression model. Death, loss to follow-up, and transfer out were 0.3%, 9.0%, and 0.7%, respectively, at 24 months. Overall attrition was 5.66/100 person-years. Patients with >3 years on ART, >500 cluster of differentiation type-4 count, body mass index >18.5, and receiving nevirapine but not stavudine showed reduced attrition. ART refill centers are a promising task-shifting model in low-prevalence urban settings with high levels of stigma and poor ART coverage.

Decentralized control of large flexible structures by joint decoupling

NASA Technical Reports Server (NTRS)

Su, Tzu-Jeng; Juang, Jer-Nan

1994-01-01

This paper presents a novel method to design decentralized controllers for large complex flexible structures by using the idea of joint decoupling. Decoupling of joint degrees of freedom from the interior degrees of freedom is achieved by setting the joint actuator commands to cancel the internal forces exerting on the joint degrees of freedom. By doing so, the interactions between substructures are eliminated. The global structure control design problem is then decomposed into several substructure control design problems. Control commands for interior actuators are set to be localized state feedback using decentralized observers for state estimation. The proposed decentralized controllers can operate successfully at the individual substructure level as well as at the global structure level. Not only control design but also control implementation is decentralized. A two-component mass-spring-damper system is used as an example to demonstrate the proposed method.

Decentralized Feedback Controllers for Exponential Stabilization of Hybrid Periodic Orbits: Application to Robotic Walking.

PubMed

Hamed, Kaveh Akbari; Gregg, Robert D

2016-07-01

This paper presents a systematic algorithm to design time-invariant decentralized feedback controllers to exponentially stabilize periodic orbits for a class of hybrid dynamical systems arising from bipedal walking. The algorithm assumes a class of parameterized and nonlinear decentralized feedback controllers which coordinate lower-dimensional hybrid subsystems based on a common phasing variable. The exponential stabilization problem is translated into an iterative sequence of optimization problems involving bilinear and linear matrix inequalities, which can be easily solved with available software packages. A set of sufficient conditions for the convergence of the iterative algorithm to a stabilizing decentralized feedback control solution is presented. The power of the algorithm is demonstrated by designing a set of local nonlinear controllers that cooperatively produce stable walking for a 3D autonomous biped with 9 degrees of freedom, 3 degrees of underactuation, and a decentralization scheme motivated by amputee locomotion with a transpelvic prosthetic leg.

Decentralized Feedback Controllers for Exponential Stabilization of Hybrid Periodic Orbits: Application to Robotic Walking*

PubMed Central

Hamed, Kaveh Akbari; Gregg, Robert D.

2016-01-01

This paper presents a systematic algorithm to design time-invariant decentralized feedback controllers to exponentially stabilize periodic orbits for a class of hybrid dynamical systems arising from bipedal walking. The algorithm assumes a class of parameterized and nonlinear decentralized feedback controllers which coordinate lower-dimensional hybrid subsystems based on a common phasing variable. The exponential stabilization problem is translated into an iterative sequence of optimization problems involving bilinear and linear matrix inequalities, which can be easily solved with available software packages. A set of sufficient conditions for the convergence of the iterative algorithm to a stabilizing decentralized feedback control solution is presented. The power of the algorithm is demonstrated by designing a set of local nonlinear controllers that cooperatively produce stable walking for a 3D autonomous biped with 9 degrees of freedom, 3 degrees of underactuation, and a decentralization scheme motivated by amputee locomotion with a transpelvic prosthetic leg. PMID:27990059

The social control of energy: A case for the promise of decentralized solar technologies

NASA Astrophysics Data System (ADS)

Gilmer, R. W.

1980-05-01

Decentralized solar technology and centralized electric utilities were contrasted in the ways they assign property rights in capital and energy output; in the assignment of operational control; and in the means of monitoring, policing, and enforcing property rights. An analogy was drawn between the decision of an energy consumer to use decentralized solar and the decision of a firm to vertically integrate, that is, to extend the boundary of a the firm to vertically integrate, that is, to extend the boundary of the firm by making inputs or further processing output. Decentralized solar energy production offers the small energy consumer the chance to cut ties to outside suppliers--to vertically integrate energy production into the home or business. The development of this analogy provides insight into important noneconomic aspects of solar energy, and it points clearly to the lighter burdens of social management offered by decentralized solar technology.

[Territory and decentralization in the agenda for productive transformation with equity].

PubMed

Sojo, A

1991-08-01

The regional perspective and the decentralization in Latin American and Caribbean countries was examined in light of technological changes and transformation of economic production to boost productivity. National population policies were not the major cause of redistribution of the population, rather such transformation significantly changed the comparative regional and urban advantages in the use of territory affecting the spatial distribution of the population. Hypotheses were advanced using the transformation of production, regional development, and decentralization on the retention, attraction, and migration of population in different areas with varying economic conditions. Spurious competitiveness means global strategies of enterprises that establish foreign operations by means of factor sourcing. Flexible specialization is a company strategy of permanent innovation based on flexible equipment and a qualified work force. The increasing transnationalization of capital is the source of skills and technology that sustain competitive advantages. Decentralization can resolve local demand, facilitate access to information, mobilize resources, and exercise control over local operations. In Japan, Germany, and Italy vs. the US and France there is a social contract among companies, trade unions, universities, and regional administrations in the interest of capital and the work force. There is no direct relationship between technology and region, the industrial cluster exhibits systemic competitiveness in developed countries (the Emilian model in Italy affirms the ability of small enterprises to develop new products), the regional impact is diverse relative to new technologies (some deprived rural economic areas have potential as in central and northern Italy), and population and region are linked (regional and rural-urban differences in the growth of population and migratory flows account for spatial distribution of the population). Decentralization and systemic competitiveness concern productivity and regional policies (spatial diversity for increased productivity) and technology and human resources are interdependent (technical progress is determined by the level of qualification of the population).

Towards Decentralized and Goal-Oriented Models of Institutional Resource Allocation: The Spanish Case

ERIC Educational Resources Information Center

Lopez, Maria Jose Gonzalez

2006-01-01

The search for more flexibility in financial management of public universities demands adjustments in budgeting strategies. International studies on this topic recommend wider financial autonomy for management units, the use of budgeting models based on performance, the implementation of formula systems for the determination of financial needs of…

The Paradox of Power in Leadership in Early Childhood Education

ERIC Educational Resources Information Center

Ho, Dora

2012-01-01

Western frameworks for school improvement, including the stakeholder model and the model of decentralized leadership, have recently been promoted as solutions for school improvement. Using early childhood education in Hong Kong as an illustrative case, this article focuses on the power and authority of leadership in school decision making. The…

Evaluation of a Decentralized Wastewater Treatment Technology. INTERNATIONAL WASTEWATER SYSTEMS, INC. MODEL 6000 SEQUENCING BATCH REACTOR SYSTEM

EPA Science Inventory

Evaluation of the IWS Model 6000 SBR began in April 2004 when one SBR was taken off line and cleaned. The verification testing started July 1, 2004 and proceeded without interruption through June 30, 2005. All sixteen four-day sampling events were completed as scheduled, yielding...

The Cohort Model: Lessons Learned When Principals Collaborate

ERIC Educational Resources Information Center

Umekubo, Lisa A.; Chrispeels, Janet H.; Daly, Alan J.

2015-01-01

This study explored a formal structure, the cohort model that a decentralized district put in place over a decade ago. Schools were clustered into cohorts to facilitate professional development for leadership teams for all 44 schools within the district. Drawing upon Senge's components of organizational learning, we used a single case study design…

Where Politics Is a Blood Sport: Restructuring State Higher Education Governance in Massachusetts

ERIC Educational Resources Information Center

Tandberg, David A.; Anderson, Christian K.

2012-01-01

The 1991 restructuring of Massachusetts system of higher education is explained and analyzed using McLendon's "Policy Stream Model of Decentralization Agenda Setting," a revised Garbage Can model, which proves useful insofar as the case is placed in its historical context. Public higher education in Massachusetts has suffered as a…

The Effect of School Autonomy and School Internal Decentralization on Students' Reading Literacy

ERIC Educational Resources Information Center

Maslowski, Ralf; Scheerens, Jaap; Luyten, Hans

2007-01-01

Over the past 2 decades, a large number of countries have been engaged in the decentralization of decision-making to schools. Although the motives and incentives for school autonomy are often diverse, it is commonly believed that decentralization will enhance the quality of schooling. Based on a secondary analysis of data from OECD's Programme for…

Efficient decentralized consensus protocols

NASA Technical Reports Server (NTRS)

Lakshman, T. V.; Agrawala, A. K.

1986-01-01

Decentralized consensus protocols are characterized by successive rounds of message interchanges. Protocols which achieve a consensus in one round of message interchange require O(N-squared) messages, where N is the number of participants. In this paper, a communication scheme, based on finite projective planes, which requires only O(N sq rt N) messages for each round is presented. Using this communication scheme, decentralized consensus protocols which achieve a consensus within two rounds of message interchange are developed. The protocols are symmetric, and the communication scheme does not impose any hierarchical structure. The scheme is illustrated using blocking and nonblocking commit protocols, decentralized extrema finding, and computation of the sum function.

Real-Time Decentralized Neural Control via Backstepping for a Robotic Arm Powered by Industrial Servomotors.

PubMed

Vazquez, Luis A; Jurado, Francisco; Castaneda, Carlos E; Santibanez, Victor

2018-02-01

This paper presents a continuous-time decentralized neural control scheme for trajectory tracking of a two degrees of freedom direct drive vertical robotic arm. A decentralized recurrent high-order neural network (RHONN) structure is proposed to identify online, in a series-parallel configuration and using the filtered error learning law, the dynamics of the plant. Based on the RHONN subsystems, a local neural controller is derived via backstepping approach. The effectiveness of the decentralized neural controller is validated on a robotic arm platform, of our own design and unknown parameters, which uses industrial servomotors to drive the joints.

A review on full-scale decentralized wastewater treatment systems: techno-economical approach.

PubMed

Singh, Nitin Kumar; Kazmi, A A; Starkl, M

2015-01-01

As a solution to the shortcomings of centralized systems, over the last two decades large numbers of decentralized wastewater treatment plants of different technology types have been installed all over the world. This paper aims at deriving lessons learned from existing decentralized wastewater treatment plants that are relevant for smaller towns (and peri-urban areas) as well as rural communities in developing countries, such as India. Only full-scale implemented decentralized wastewater treatment systems are reviewed in terms of performance, land area requirement, capital cost, and operation and maintenance costs. The results are presented in tables comparing different technology types with respect to those parameters.

A modified approach to controller partitioning

NASA Technical Reports Server (NTRS)

Garg, Sanjay; Veillette, Robert J.

1993-01-01

The idea of computing a decentralized control law for the integrated flight/propulsion control of an aircraft by partitioning a given centralized controller is investigated. An existing controller partitioning methodology is described, and a modified approach is proposed with the objective of simplifying the associated controller approximation problem. Under the existing approach, the decentralized control structure is a variable in the partitioning process; by contrast, the modified approach assumes that the structure is fixed a priori. Hence, the centralized controller design may take the decentralized control structure into account. Specifically, the centralized controller may be designed to include all the same inputs and outputs as the decentralized controller; then, the two controllers may be compared directly, simplifying the partitioning process considerably. Following the modified approach, a centralized controller is designed for an example aircraft mode. The design includes all the inputs and outputs to be used in a specified decentralized control structure. However, it is shown that the resulting centralized controller is not well suited for approximation by a decentralized controller of the given structure. The results indicate that it is not practical in general to cast the controller partitioning problem as a direct controller approximation problem.

On decentralized adaptive full-order sliding mode control of multiple UAVs.

PubMed

Xiang, Xianbo; Liu, Chao; Su, Housheng; Zhang, Qin

2017-11-01

In this study, a novel decentralized adaptive full-order sliding mode control framework is proposed for the robust synchronized formation motion of multiple unmanned aerial vehicles (UAVs) subject to system uncertainty. First, a full-order sliding mode surface in a decentralized manner is designed to incorporate both the individual position tracking error and the synchronized formation error while the UAV group is engaged in building a certain desired geometric pattern in three dimensional space. Second, a decentralized virtual plant controller is constructed which allows the embedded low-pass filter to attain the chattering free property of the sliding mode controller. In addition, robust adaptive technique is integrated in the decentralized chattering free sliding control design in order to handle unknown bounded uncertainties, without requirements for assuming a priori knowledge of bounds on the system uncertainties as stated in conventional chattering free control methods. Subsequently, system robustness as well as stability of the decentralized full-order sliding mode control of multiple UAVs is synthesized. Numerical simulation results illustrate the effectiveness of the proposed control framework to achieve robust 3D formation flight of the multi-UAV system. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

An Allocation Model for Teaching and Non-Teaching Staff in a Decentralized Institution. AIR 1984 Annual Forum Paper.

ERIC Educational Resources Information Center

Dijkman, Frank G.

A new allocation model for teaching and nonteaching staff has been developed at the University of Utrecht, in the Netherlands. The model may be characterized as highly normative, leading to lump sums to be allocated to academic departments. These departments in turn are free, within constraints, to budget their activities differently than is…

Model reference, sliding mode adaptive control for flexible structures

NASA Technical Reports Server (NTRS)

Yurkovich, S.; Ozguner, U.; Al-Abbass, F.

1988-01-01

A decentralized model reference adaptive approach using a variable-structure sliding model control has been developed for the vibration suppression of large flexible structures. Local models are derived based upon the desired damping and response time in a model-following scheme, and variable structure controllers are then designed which employ colocated angular rate and position feedback. Numerical simulations have been performed using NASA's flexible grid experimental apparatus.

Modeling and control of flexible space platforms with articulated payloads

NASA Technical Reports Server (NTRS)

Graves, Philip C.; Joshi, Suresh M.

1989-01-01

The first steps in developing a methodology for spacecraft control-structure interaction (CSI) optimization are identification and classification of anticipated missions, and the development of tractable mathematical models in each mission class. A mathematical model of a generic large flexible space platform (LFSP) with multiple independently pointed rigid payloads is considered. The objective is not to develop a general purpose numerical simulation, but rather to develop an analytically tractable mathematical model of such composite systems. The equations of motion for a single payload case are derived, and are linearized about zero steady-state. The resulting model is then extended to include multiple rigid payloads, yielding the desired analytical form. The mathematical models developed clearly show the internal inertial/elastic couplings, and are therefore suitable for analytical and numerical studies. A simple decentralized control law is proposed for fine pointing the payloads and LFSP attitude control, and simulation results are presented for an example problem. The decentralized controller is shown to be adequate for the example problem chosen, but does not, in general, guarantee stability. A centralized dissipative controller is then proposed, requiring a symmetric form of the composite system equations. Such a controller guarantees robust closed loop stability despite unmodeled elastic dynamics and parameter uncertainties.

Is Ontario Selling Its Children Short?

ERIC Educational Resources Information Center

Grossman, Alana; Jordan, Anne

1998-01-01

Ontario, Canada's grassroots movement toward integrating disabled students harmonizes with governmental intentions to reduce costs while preserving student rights and accountability. However, decentralized, market-driven models hamper equity. More students are labelled exceptional, schools target privileged enrollees, minority students lack…

Extended Decentralized Linear-Quadratic-Gaussian Control

NASA Technical Reports Server (NTRS)

Carpenter, J. Russell

2000-01-01

A straightforward extension of a solution to the decentralized linear-Quadratic-Gaussian problem is proposed that allows its use for commonly encountered classes of problems that are currently solved with the extended Kalman filter. This extension allows the system to be partitioned in such a way as to exclude the nonlinearities from the essential algebraic relationships that allow the estimation and control to be optimally decentralized.

Globalisation and human dignity: the case of the information superhighway.

PubMed

Hamelink, C J

1996-01-01

In 1994, Vice President Al Gore coined the concept of the Information Superhighway during a speech in Buenos Aires in which he proposed the development of a global information infrastructure. The project envisions the incorporation of all existing communication networks into one system, facilitating the globalization of markets. The internet, a decentralized network of computer networks, is one small-scale, existing model of what the superhighway could be, a public space owned by nobody in which communication takes place largely for noncommercial purposes. The internet currently connects 40 million computer users from at least 90 countries. The alternative model for the superhighway is the privately managed global shopping mall, a global interactive marketplace for information, entertainment, and advertising. The author warns, however, that it is not possible to predict the future social impact of such an information superhighway. Decision makers nonetheless push ahead in development, full of confidence in the merit and infallibility of technology. Since one cannot accurately predict the future, it rational to assume that social consequences may both promote and threaten human dignity. The author explains at which level he believes the superhighway threatens the human rights norms of equality, inviolability, and liberty, and discusses what the World Association for Christian Communication can do.

Using structured decision making to manage disease risk for Montana wildlife

USGS Publications Warehouse

Mitchell, Michael S.; Gude, Justin A.; Anderson, Neil J.; Ramsey, Jennifer M.; Thompson, Michael J.; Sullivan, Mark G.; Edwards, Victoria L.; Gower, Claire N.; Cochrane, Jean Fitts; Irwin, Elise R.; Walshe, Terry

2013-01-01

We used structured decision-making to develop a 2-part framework to assist managers in the proactive management of disease outbreaks in Montana, USA. The first part of the framework is a model to estimate the probability of disease outbreak given field observations available to managers. The second part of the framework is decision analysis that evaluates likely outcomes of management alternatives based on the estimated probability of disease outbreak, and applies managers' values for different objectives to indicate a preferred management strategy. We used pneumonia in bighorn sheep (Ovis canadensis) as a case study for our approach, applying it to 2 populations in Montana that differed in their likelihood of a pneumonia outbreak. The framework provided credible predictions of both probability of disease outbreaks, as well as biological and monetary consequences of management actions. The structured decision-making approach to this problem was valuable for defining the challenges of disease management in a decentralized agency where decisions are generally made at the local level in cooperation with stakeholders. Our approach provides local managers with the ability to tailor management planning for disease outbreaks to local conditions. Further work is needed to refine our disease risk models and decision analysis, including robust prediction of disease outbreaks and improved assessment of management alternatives.

Modular synchronization in complex networks.

PubMed

Oh, E; Rho, K; Hong, H; Kahng, B

2005-10-01

We study the synchronization transition (ST) of a modified Kuramoto model on two different types of modular complex networks. It is found that the ST depends on the type of intermodular connections. For the network with decentralized (centralized) intermodular connections, the ST occurs at finite coupling constant (behaves abnormally). Such distinct features are found in the yeast protein interaction network and the Internet, respectively. Moreover, by applying the finite-size scaling analysis to an artificial network with decentralized intermodular connections, we obtain the exponent associated with the order parameter of the ST to be beta approximately 1 different from beta(MF) approximately 1/2 obtained from the scale-free network with the same degree distribution but the absence of modular structure, corresponding to the mean field value.

Linear decentralized systems with special structure. [for twin lift helicopters

NASA Technical Reports Server (NTRS)

Martin, C. F.

1982-01-01

Certain fundamental structures associated with linear systems having internal symmetries are outlined. It is shown that the theory of finite-dimensional algebras and their representations are closely related to such systems. It is also demonstrated that certain problems in the decentralized control of symmetric systems are equivalent to long-standing problems of linear systems theory. Even though the structure imposed arose in considering the problems of twin-lift helicopters, any large system composed of several identical intercoupled control systems can be modeled by a linear system that satisfies the constraints imposed. Internal symmetry can be exploited to yield new system-theoretic invariants and a better understanding of the way in which the underlying structure affects overall system performance.

Decentralized Interleaving of Paralleled Dc-Dc Buck Converters: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Johnson, Brian B; Rodriguez, Miguel; Sinha, Mohit

We present a decentralized control strategy that yields switch interleaving among parallel connected dc-dc buck converters without communication. The proposed method is based on the digital implementation of the dynamics of a nonlinear oscillator circuit as the controller. Each controller is fully decentralized, i.e., it only requires the locally measured output current to synthesize the pulse width modulation (PWM) carrier waveform. By virtue of the intrinsic electrical coupling between converters, the nonlinear oscillator-based controllers converge to an interleaved state with uniform phase-spacing across PWM carriers. To the knowledge of the authors, this work represents the first fully decentralized strategy formore » switch interleaving of paralleled dc-dc buck converters.« less

The school as a force for community change in Tanzania

NASA Astrophysics Data System (ADS)

Maliyamkono, T. L.

1980-09-01

In newly independent countries where traditional theories of educational policy have continued to be followed, education has persisted as little more than a sophisticated mechanism for the recruitment of elites, and there has been an increased dependence on the advanced industrial nations for aid, experts and educational models. Tanzania, however, has attempted to break away from traditional strategies, and the author here describes and analyses the impact of two of the most far-reaching reforms — Education for Self-Reliance, and Decentralization — on national goals and policies. President Nyerere enunciated the objectives for Education for Self-Reliance in 1967 as relating education to rural life, correcting the elitist bias of education, and changing negative attitudes among students towards agriculture and rural life. Five major programmes of reform covering primary and secondary education, teacher and higher education, and examinations were to be pursued, ensuring a closer integration of schools with local communities, e.g., through school farms and co-operative shops, and making curricula directly relevant to local needs. A policy of Decentralization is being implemented, allowing, theoretically at least, a much greater participation at community level in decision-making. In primary and adult education this has already been effected to some extent, though there is evidence to suggest that decentralization in some regions and districts has resulted in the creation of local bureaucratic machinery for control, defeating the intention of the reform. Decentralization of secondary and teacher education is likely to follow, leaving only higher education centrally controlled for manpower training and allocation purposes. Finally the author discusses the question of the transferability of the Tanzanian reforms.

Performance of HIV care decentralization from the patient's perspective: health-related quality of life and perceived quality of services in Cameroon.

PubMed

Boyer, Sylvie; Protopopescu, Camelia; Marcellin, Fabienne; Carrieri, Maria Patrizia; Koulla-Shiro, Sinata; Moatti, Jean-Paul; Spire, Bruno

2012-07-01

(i) To assess HIV care decentralization in Cameroon from the patients' point of view, in terms of health-related quality of life (HRQL) and perceived quality of services; (ii) to identify patient- and hospital-related factors undermining HRQL. Perceived quality of services was compared among 1985 HIV-infected patients treated with antiretroviral therapy (ART) for at least 6 months in 27 treatment centres at different levels of health care delivery (central, provincial and district) (EVAL-ANRS 12-116 survey, 2007) using chi-square and non-parametric tests. Correlates of the SF-12 physical (PCS) and mental (MCS) HRQL scores were identified using two-level linear models. Patients followed-up at central and district levels had similar physical HRQL, while those followed-up at the more decentralized district level reported significantly better mental HRQL. Patients at district level also expressed better relationships with caregivers, easier access to consultations and more reliable drug supply. Financial barriers to access to HIV care and self-reported side-effects were independently associated with both lower PCS and lower MCS. Caregivers' heavy workload tended to impair both PCS and MCS, while availability of counselling by social workers in the hospital was independently associated with higher MCS. Despite limited resources, the decentralization of ART delivery can improve quality of care, providing a positive impact on HIV-infected patients' well-being. The development of psychosocial support interventions is necessary but not sufficient for improving quality of care in ART scaling-up programmes, and should be related to global strengthening of health human resources.

[Decentralization, AIDS, and harm reduction: the implementation of public policies in Rio de Janeiro, Brazil].

PubMed

Fonseca, Elize Massard da; Nunn, Amy; Souza-Junior, Paulo Borges; Bastos, Francisco Inácio; Ribeiro, José Mendes

2007-09-01

This paper assesses how decentralization of resources and initiatives by the Brazilian National SDT/AIDS Program has impacted the transfer of funds for programs to prevent HIV/AIDS among injecting drug users in Rio de Janeiro, Brazil (1999-2006). The effects of the decentralization policy on Rio de Janeiro's Syringe Exchange Programs (SEPs) are assessed in detail. Decentralization effectively took place in Rio de Janeiro in 2006, with the virtual elimination of any direct transfer from the Federal government. The elimination of direct transfers forced SEPs to seek alternative funding sources. The structure of local SEPs appears to be weak and has been further undermined by current funding constraints. Of 22 SEPs operating in 2002, only two are still operational in 2006, basically funded by the State Health Secretariat and one municipal government. The current discontinuity of SEP operations may favor the resurgence of AIDS in the IDU population. A more uniform, regulated decentralization process is thus needed.

The recent process of decentralization and democratic management of education in Brazil

NASA Astrophysics Data System (ADS)

Santos Filho, José Camilo Dos

1993-09-01

Brazilian society is beginning a new historical period in which the principle of decentralization is beginning to predominate over centralization, which held sway during the last 25 years. In contrast to recent Brazilian history, there is now a search for political, democratic and participatory decentralization more consonant with grass-roots aspirations. The first section of this article presents a brief analysis of some decentralization policies implemented by the military regime of 1964, and discusses relevant facts related to the resistance of civil society to state authoritarianism, and to the struggle for the democratization and organization of civil society up to the end of the 1970s. The second section analyzes some new experiences of democratic public school administration initiated in the 1970s and 1980s. The final section discusses the move toward decentralization and democratization of public school administration in the new Federal and State Constitutions, and in the draft of the new Law of National Education.

Taming instabilities in power grid networks by decentralized control

NASA Astrophysics Data System (ADS)

Schäfer, B.; Grabow, C.; Auer, S.; Kurths, J.; Witthaut, D.; Timme, M.

2016-05-01

Renewables will soon dominate energy production in our electric power system. And yet, how to integrate renewable energy into the grid and the market is still a subject of major debate. Decentral Smart Grid Control (DSGC) was recently proposed as a robust and decentralized approach to balance supply and demand and to guarantee a grid operation that is both economically and dynamically feasible. Here, we analyze the impact of network topology by assessing the stability of essential network motifs using both linear stability analysis and basin volume for delay systems. Our results indicate that if frequency measurements are averaged over sufficiently large time intervals, DSGC enhances the stability of extended power grid systems. We further investigate whether DSGC supports centralized and/or decentralized power production and find it to be applicable to both. However, our results on cycle-like systems suggest that DSGC favors systems with decentralized production. Here, lower line capacities and lower averaging times are required compared to those with centralized production.

Impact of patient and program factors on default during treatment of multidrug-resistant tuberculosis.

PubMed

Gler, M T; Podewils, L J; Munez, N; Galipot, M; Quelapio, M I D; Tupasi, T E

2012-07-01

In the Philippines, programmatic treatment of drug-resistant tuberculosis (TB) was initiated by the Tropical Disease Foundation in 1999 and transitioned to the National TB Program in 2006. To determine patient and socio-demographic characteristics associated with default, and the impact of patient support measures on default. Retrospective cohort analysis of 583 MDR-TB patients treated from 1999 to 2006. A total of 88 (15%) patients defaulted from treatment. The median follow-up time for patients who defaulted was 289 days (range 1-846). In multivariate analysis adjusted for age, sex and previous TB treatment, receiving a greater number of treatment drugs (≥ 5 vs. 2-3 drugs, HR 7.2, 95%CI 3.3-16.0, P < 0.001) was significantly associated with an increased risk of default, while decentralization reduced the risk of default (HR 0.3, 95%CI 0.2-0.7, P < 0.001). Improving access to treatment for MDR-TB through decentralization of care to centers near the patient's residence reduced the risk of default. Further research is needed to evaluate the feasibility, impact and cost-effectiveness of decentralized care models for MDR-TB treatment.

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

PubMed Central

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

2016-01-01

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. PMID:27537894

Decentralized system identification using stochastic subspace identification on wireless smart sensor networks

NASA Astrophysics Data System (ADS)

Sim, Sung-Han; Spencer, Billie F., Jr.; Park, Jongwoong; Jung, Hyungjo

2012-04-01

Wireless Smart Sensor Networks (WSSNs) facilitates a new paradigm to structural identification and monitoring for civil infrastructure. Conventional monitoring systems based on wired sensors and centralized data acquisition and processing have been considered to be challenging and costly due to cabling and expensive equipment and maintenance costs. WSSNs have emerged as a technology that can overcome such difficulties, making deployment of a dense array of sensors on large civil structures both feasible and economical. However, as opposed to wired sensor networks in which centralized data acquisition and processing is common practice, WSSNs require decentralized computing algorithms to reduce data transmission due to the limitation associated with wireless communication. Thus, several system identification methods have been implemented to process sensor data and extract essential information, including Natural Excitation Technique with Eigensystem Realization Algorithm, Frequency Domain Decomposition (FDD), and Random Decrement Technique (RDT); however, Stochastic Subspace Identification (SSI) has not been fully utilized in WSSNs, while SSI has the strong potential to enhance the system identification. This study presents a decentralized system identification using SSI in WSSNs. The approach is implemented on MEMSIC's Imote2 sensor platform and experimentally verified using a 5-story shear building model.

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

PubMed

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.

Decentralized semi-active damping of free structural vibrations by means of structural nodes with an on/off ability to transmit moments

NASA Astrophysics Data System (ADS)

Poplawski, Blazej; Mikułowski, Grzegorz; Mróz, Arkadiusz; Jankowski, Łukasz

2018-02-01

This paper proposes, tests numerically and verifies experimentally a decentralized control algorithm with local feedback for semi-active mitigation of free vibrations in frame structures. The algorithm aims at transferring the vibration energy of low-order, lightly-damped structural modes into high-frequency modes of vibration, where it is quickly damped by natural mechanisms of material damping. Such an approach to mitigation of vibrations, known as the prestress-accumulation release (PAR) strategy, has been earlier applied only in global control schemes to the fundamental vibration mode of a cantilever beam. In contrast, the decentralization and local feedback allows the approach proposed here to be applied to more complex frame structures and vibration patterns, where the global control ceases to be intuitively obvious. The actuators (truss-frame nodes with controllable ability to transmit moments) are essentially unblockable hinges that become unblocked only for very short time periods in order to trigger local modal transfer of energy. The paper proposes a computationally simple model of the controllable nodes, specifies the control performance measure, yields basic characteristics of the optimum control, proposes the control algorithm and then tests it in numerical and experimental examples.

Decentralized Hypothesis Testing in Energy Harvesting Wireless Sensor Networks

NASA Astrophysics Data System (ADS)

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.

Framing the difficulties resulting from implementing a Participatory Management Model in a public hospital.

PubMed

Bernardes, Andrea; Cummings, Greta; Évora, Yolanda Dora Martinez; Gabriel, Carmen Silvia

2012-01-01

This study aims to address difficulties reported by the nursing team during the process of changing the management model in a public hospital in Brazil. This qualitative study used thematic content analysis as proposed by Bardin, and data were analyzed using the theoretical framework of Bolman and Deal. The vertical implementation of Participatory Management contradicted its underlying philosophy and thereby negatively influenced employee acceptance of the change. The decentralized structure of the Participatory Management Model was implemented but shared decision-making was only partially utilized. Despite facilitation of the communication process within the unit, more significant difficulties arose from lack of communication inter-unit. Values and principals need to be shared by teams, however, that will happens only if managers restructure accountabilities changing job descriptions of all team members. Innovative management models that depart from the premise of decentralized decision-making and increased communication encourage accountability, increased motivation and satisfaction, and contribute to improving the quality of care. The contribution of the study is that it describes the complexity of implementing an innovative management model, examines dissent and intentionally acknowledges the difficulties faced by employees in the organization.

Jealousy Graphs: Structure and Complexity of Decentralized Stable Matching

DTIC Science & Technology

2013-01-01

REPORT Jealousy Graphs: Structure and Complexity of Decentralized Stable Matching 14. ABSTRACT 16. SECURITY CLASSIFICATION OF: The stable matching...Franceschetti 858-822-2284 3. DATES COVERED (From - To) Standard Form 298 (Rev 8/98) Prescribed by ANSI Std. Z39.18 - Jealousy Graphs: Structure and...market. Using this structure, we are able to provide a ner analysis of the complexity of a subclass of decentralized matching markets. Jealousy

Centralization or decentralization of facial structures in Korean young adults.

PubMed

Yoo, Ja-Young; Kim, Jeong-Nam; Shin, Kang-Jae; Kim, Soon-Heum; Choi, Hyun-Gon; Jeon, Hyun-Soo; Koh, Ki-Seok; Song, Wu-Chul

2013-05-01

It is well known that facial beauty is dictated by facial type, and harmony between the eyes, nose, and mouth. Furthermore, facial impression is judged according to the overall facial contour and the relationship between the facial structures. The aims of the present study were to determine the optimal criteria for the assessment of gathering or separation of the facial structures and to define standardized ratios for centralization or decentralization of the facial structures.Four different lengths were measured, and 2 indexes were calculated from standardized photographs of 551 volunteers. Centralization and decentralization were assessed using the width index (interpupillary distance / facial width) and height index (eyes-mouth distance / facial height). The mean ranges of the width index and height index were 42.0 to 45.0 and 36.0 to 39.0, respectively. The width index did not differ with sex, but males had more decentralized faces, and females had more centralized faces, vertically. The incidence rate of decentralized faces among the men was 30.3%, and that of centralized faces among the women was 25.2%.The mean ranges in width and height indexes have been determined in a Korean population. Faces with width and height index scores under and over the median ranges are determined to be "centralized" and "decentralized," respectively.

Assessing Location and Scale of Urban Nonpotable Water Reuse Systems for Life-Cycle Energy Consumption and Greenhouse Gas Emissions.

PubMed

Kavvada, Olga; Horvath, Arpad; Stokes-Draut, Jennifer R; Hendrickson, Thomas P; Eisenstein, William A; Nelson, Kara L

2016-12-20

Nonpotable water reuse (NPR) is one option for conserving valuable freshwater resources. Decentralization can improve distribution system efficiency by locating treatment closer to the consumer; however, small treatment systems may have higher unit energy and greenhouse-gas (GHG) emissions. This research explored the trade-off between residential NPR systems using a life-cycle approach to analyze the energy use and GHG emissions. Decentralized and centralized NPR options are compared to identify where decentralized systems achieve environmental advantages over centralized reuse alternatives, and vice versa, over a range of scales and spatial and demographic conditions. For high-elevation areas far from the centralized treatment plant, decentralized NPR could lower energy use by 29% and GHG emissions by 28%, but in low-elevation areas close to the centralized treatment plant, decentralized reuse could be higher by up to 85% (energy) and 49% (GHG emissions) for the scales assessed (20-2000 m 3 /day). Direct GHG emissions from the treatment processes were found to be highly uncertain and variable and were not included in the analysis. The framework presented can be used as a planning support tool to reveal the environmental impacts of integrating decentralized NPR with existing centralized wastewater infrastructure and can be adapted to evaluate different treatment technology scales for reuse.

Financial management systems under decentralization and their effect on malaria control in Uganda.

PubMed

Kivumbi, George W; Nangendo, Florence; Ndyabahika, Boniface Rutagira

2004-01-01

A descriptive case study with multiple sites and a single level of analysis was carried out in four purposefully selected administrative districts of Uganda to investigate the effect of financial management systems under decentralization on malaria control. Data were primarily collected from 36 interviews with district managers, staff at health units and local leaders. A review of records and documents related to decentralization at the central and district level was also used to generate data for the study. We found that a long, tedious, and bureaucratic process combined with lack of knowledge in working with new financial systems by several actors characterized financial flow under decentralization. This affected the timely use of financial resources for malaria control in that there were funds in the system that could not be accessed for use. We were also told that sometimes these funds were returned to the central government because of non-use due to difficulties in accessing them and/or stringent conditions not to divert them to other uses. Our data showed that a cocktail of bureaucratic control systems, corruption and incompetence make the financial management system under decentralization counter-productive for malaria control. The main conclusion is that good governance through appropriate and efficient financial management systems is very important for effective malaria control under decentralization.

Compact Ocean Models Enable Onboard AUV Autonomy and Decentralized Adaptive Sampling

DTIC Science & Technology

2013-09-30

NCOM) and a biochemical model which includes three nutrients, two phytoplankton groups (diatoms and small phytoplankton ), two groups of zooplankton...properties (chlorophyll-a and absorption due to phytoplankton ), the model was able to reproduce intensity and tendencies in surface and subsurface...following emergence, growth, and decay of phytoplankton bloom patches in Monterey Bay. REFERENCES ● Frolov, S., A. M. Baptista, Y. Zhang, C

Compact Ocean Models Enable Onboard AUV Autonomy and Decentralized Adaptive Sampling

DTIC Science & Technology

2014-09-30

1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Compact Ocean Models Enable Onboard AUV Autonomy and...transmitted onboard an AUV . 3. Develop algorithms for adaptive planning of AUV surveys. 4. Demonstrate use of compact ocean models onboard a long...range AUV during a field deployment. Report Documentation Page Form ApprovedOMB No. 0704-0188 Public reporting burden for the collection of

Managing diverse occupational therapy resources in a creative, corporate model.

PubMed

Baptiste, S

1993-10-01

Two occupational therapy departments were amalgamated into a corporate whole and charged with the development of a workable, corporate structure. The departmental model which was developed served to enhance the concepts of quality of working life, employee autonomy, management team and quality circle theory. This paper provides a background from business and organizational literature, and outlines the development of the departmental model, in concert with the adoption of the client-centred model of occupational performance as a department basis for practice. This development was taking place concurrently with larger, institutional changes into a decentralized clinical programme management model. Discussion highlights the level of staff satisfaction with the changes, areas of concern during the development of the system and plans for the future growth. During this period of massive and critical change in the delivery of health care services, there has been a trend in restructuring health care institutions towards decentralized models. This paper will describe the experience of one occupational therapy department in developing an innovative departmental structure involving participatory management amalgamation. It is believed that the experience of the past occupational therapy work units with one viable option for a renewed management model. Staff skill sets can be maximized and optimal potential realized while faced with inevitable resource shrinkage and service reorganization.

Evaluating a De-Centralized Regional Delivery System for Breast Cancer Screening and Patient Navigation for the Rural Underserved.

PubMed

Inrig, Stephen J; Tiro, Jasmin A; Melhado, Trisha V; Argenbright, Keith E; Craddock Lee, Simon J

2014-01-01

Providing breast cancer screening services in rural areas is challenging due to the fractured nature of healthcare delivery systems and complex reimbursement mechanisms that create barriers to access for the under- and uninsured. Interventions that reduce structural barriers to mammography, like patient navigation programs, are effective and recommended, especially for minority and underserved women. Although the literature on rural healthcare is significant, the field lacks studies of adaptive service delivery models and rigorous evaluation of evidence-based programs that facilitate routine screening and appropriate follow-up across large geographic areas. To better understand how to implement a decentralized regional delivery "hub & spoke" model for rural breast cancer screening and patient navigation, we have designed a rigorous, structured, multi-level and mixed-methods evaluation based on Glasgow's RE-AIM model (Reach, Effectiveness, Adoption, Implementation, and Maintenance). The program is comprised of three core components: 1) Outreach to underserved women by partnering with county organizations; 2) Navigation to guide patients through screening and appropriate follow-up; and 3) Centralized Reimbursement to coordinate funding for screening services through a central contract with Medicaid Breast and Cervical Cancer Services (BCCS). Using Glasgow's RE-AIM model, we will: 1) assess which counties have the resources and capacity to implement outreach and/or navigation components, 2) train partners in each county on how to implement components, and 3) monitor process and outcome measures in each county at regular intervals, providing booster training when needed. This evaluation strategy will elucidate how the heterogeneity of rural county infrastructure impacts decentralized service delivery as a navigation program expands. In addition to increasing breast cancer screening access, our model improves and maintains time to diagnostic resolution and facilitates timely referral to local cancer treatment services. We offer this evaluation approach as an exemplar for scientific methods to evaluate the translation of evidence-based federal policy into sustainable health services delivery in a rural setting.

Evaluating a De-Centralized Regional Delivery System for Breast Cancer Screening and Patient Navigation for the Rural Underserved

PubMed Central

Inrig, Stephen J.; Tiro, Jasmin A.; Melhado, Trisha V.; Argenbright, Keith E.; Craddock Lee, Simon J.

2017-01-01

Providing breast cancer screening services in rural areas is challenging due to the fractured nature of healthcare delivery systems and complex reimbursement mechanisms that create barriers to access for the under- and uninsured. Interventions that reduce structural barriers to mammography, like patient navigation programs, are effective and recommended, especially for minority and underserved women. Although the literature on rural healthcare is significant, the field lacks studies of adaptive service delivery models and rigorous evaluation of evidence-based programs that facilitate routine screening and appropriate follow-up across large geographic areas. Objectives To better understand how to implement a decentralized regional delivery “hub & spoke” model for rural breast cancer screening and patient navigation, we have designed a rigorous, structured, multi-level and mixed-methods evaluation based on Glasgow’s RE-AIM model (Reach, Effectiveness, Adoption, Implementation, and Maintenance). Methods and Design The program is comprised of three core components: 1) Outreach to underserved women by partnering with county organizations; 2) Navigation to guide patients through screening and appropriate follow-up; and 3) Centralized Reimbursement to coordinate funding for screening services through a central contract with Medicaid Breast and Cervical Cancer Services (BCCS). Using Glasgow’s RE-AIM model, we will: 1) assess which counties have the resources and capacity to implement outreach and/or navigation components, 2) train partners in each county on how to implement components, and 3) monitor process and outcome measures in each county at regular intervals, providing booster training when needed. Discussion This evaluation strategy will elucidate how the heterogeneity of rural county infrastructure impacts decentralized service delivery as a navigation program expands. In addition to increasing breast cancer screening access, our model improves and maintains time to diagnostic resolution and facilitates timely referral to local cancer treatment services. We offer this evaluation approach as an exemplar for scientific methods to evaluate the translation of evidence-based federal policy into sustainable health services delivery in a rural setting. PMID:28713882

Corporate Restructuring and Liberal Learning.

ERIC Educational Resources Information Center

Useem, Michael

1995-01-01

This paper contends that trends in business (restructuring, downsizing, decentralization, managerial empowerment, internationalization) strongly imply a need to reorganize the college curriculum to provide future professionals with the skills and intellect to meet multiple economic and organizational challenges. This means a new learning model and…

Micmac Indian Social Work Education: A Model.

ERIC Educational Resources Information Center

Smith, Ann F. V.; Pace, Jacqueline M.

1987-01-01

Describes founding, goals, admissions, and implementation of a five-year Micmac Bachelor of Social Work Program at Dalhousie University. Discusses advantages and problems of a decentralized program sponsored by diverse organizations/agencies. Outlines degree requirements, staff qualifications, student personal/financial needs, and program changes…

The Educationally Challenged American School District.

ERIC Educational Resources Information Center

Clinchy, Evans

1998-01-01

Two national reform movements--one focused on creating small, autonomous schools, the other fixated on a standardization agenda--are basically in conflict. The standards movement is touting the traditional, top-down, centralized, bureaucratic system modeled after Frederick Taylor and his efficiency experts. Progressive, decentralized initiatives…

Decentralized Control of Autonomous Vehicles

DTIC Science & Technology

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

Decentralized regulation of dynamic systems. [for controlling large scale linear systems

NASA Technical Reports Server (NTRS)

Chu, K. C.

1975-01-01

A special class of decentralized control problem is discussed in which the objectives of the control agents are to steer the state of the system to desired levels. Each agent is concerned about certain aspects of the state of the entire system. The state and control equations are given for linear time-invariant systems. Stability and coordination, and the optimization of decentralized control are analyzed, and the information structure design is presented.

Decentralized Interleaving of Paralleled Dc-Dc Buck Converters

DOE Office of Scientific and Technical Information (OSTI.GOV)

Johnson, Brian B; Rodriguez, Miguel; Sinha, Mohit

We present a decentralized control strategy that yields switch interleaving among parallel-connected dc-dc buck converters. The proposed method is based on the digital implementation of the dynamics of a nonlinear oscillator circuit as the controller. Each controller is fully decentralized, i.e., it only requires the locally measured output current to synthesize the pulse width modulation (PWM) carrier waveform and no communication between different controllers is needed. By virtue of the intrinsic electrical coupling between converters, the nonlinear oscillator-based controllers converge to an interleaved state with uniform phase-spacing across PWM carriers. To the knowledge of the authors, this work presents themore » first fully decentralized strategy for switch interleaving in paralleled dc-dc buck converters.« less

Decentralized state estimation for a large-scale spatially interconnected system.

PubMed

Liu, Huabo; Yu, Haisheng

2018-03-01

A decentralized state estimator is derived for the spatially interconnected systems composed of many subsystems with arbitrary connection relations. An optimization problem on the basis of linear matrix inequality (LMI) is constructed for the computations of improved subsystem parameter matrices. Several computationally effective approaches are derived which efficiently utilize the block-diagonal characteristic of system parameter matrices and the sparseness of subsystem connection matrix. Moreover, this decentralized state estimator is proved to converge to a stable system and obtain a bounded covariance matrix of estimation errors under certain conditions. Numerical simulations show that the obtained decentralized state estimator is attractive in the synthesis of a large-scale networked system. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

Decentralized Estimation and Control for Preserving the Strong Connectivity of Directed Graphs.

PubMed

Sabattini, Lorenzo; Secchi, Cristian; Chopra, Nikhil

2015-10-01

In order to accomplish cooperative tasks, decentralized systems are required to communicate among each other. Thus, maintaining the connectivity of the communication graph is a fundamental issue. Connectivity maintenance has been extensively studied in the last few years, but generally considering undirected communication graphs. In this paper, we introduce a decentralized control and estimation strategy to maintain the strong connectivity property of directed communication graphs. In particular, we introduce a hierarchical estimation procedure that implements power iteration in a decentralized manner, exploiting an algorithm for balancing strongly connected directed graphs. The output of the estimation system is then utilized for guaranteeing preservation of the strong connectivity property. The control strategy is validated by means of analytical proofs and simulation results.

Electric Water Heater Modeling and Control Strategies for Demand Response

DOE Office of Scientific and Technical Information (OSTI.GOV)

Diao, Ruisheng; Lu, Shuai; Elizondo, Marcelo A.

2012-07-22

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

Digital signal processing and control and estimation theory -- Points of tangency, area of intersection, and parallel directions

NASA Technical Reports Server (NTRS)

Willsky, A. S.

1976-01-01

A number of current research directions in the fields of digital signal processing and modern control and estimation theory were studied. Topics such as stability theory, linear prediction and parameter identification, system analysis and implementation, two-dimensional filtering, decentralized control and estimation, image processing, and nonlinear system theory were examined in order to uncover some of the basic similarities and differences in the goals, techniques, and philosophy of the two disciplines. An extensive bibliography is included.

Mild decentration measured by a Scheimpflug camera and its impact on visual quality following SMILE in the early learning curve.

PubMed

Li, Meiyan; Zhao, Jing; Miao, Huamao; Shen, Yang; Sun, Ling; Tian, Mi; Wadium, Elizabeth; Zhou, Xingtao

2014-05-20

To measure decentration following femtosecond laser small incision lenticule extraction (SMILE) for the correction of myopia and myopic astigmatism in the early learning curve, and to investigate its impact on visual quality. A total of 55 consecutive patients (100 eyes) who underwent the SMILE procedure were included. Decentration was measured using a Scheimpflug camera 6 months after surgery. Uncorrected and corrected distance visual acuity (UDVA, CDVA), manifest refraction, and wavefront errors were also measured. Associations between decentration and the preoperative spherical equivalent were analyzed, as well as the associations between decentration and wavefront aberrations. Regarding efficacy and safety, 40 eyes (40%) had an unchanged CDVA; 32 eyes (32%) gained one line; and 11 eyes (11%) gained two lines. Fifteen eyes (15%) lost one line of CDVA, and two eyes (2%) lost two lines. Ninety-nine of the treated eyes (99%) had a postoperative UDVA better than 1.0, and 100 eyes (100%) had a UDVA better than 0.8. The mean decentered displacement was 0.17 ± 0.09 mm. The decentered displacement of all treated eyes (100%) was within 0.50 mm; 70 eyes (70%) were within 0.20 mm; and 90 eyes (90%) were within 0.30 mm. The vertical coma showed the greatest increase in magnitude. The magnitude of horizontal decentration was found to be associated with an induced horizontal coma. This study suggests that, although mild decentration occurred in the early learning curve, good visual outcomes were achieved after the SMILE surgery. Special efforts to minimize induced vertical coma are necessary. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

Decentralization and central and regional coordination of health services: the case of Switzerland.

PubMed

Wyss, K; Lorenz, N

2000-01-01

As part of reforms in the health care delivery sector, decentralization is currently promoted in many countries as a means to improve performance and outcomes of national health care systems. Switzerland is an example of a country with a long-standing tradition of decentralized organization for many purposes, including health care delivery. Apart from the few aspects where the responsibility is at the federal level, it is the task of the 26 cantons to organize the provision of health services for the population of around 7 million people. This permits the system to be responsive to local priorities and interest as well as to new developments in medical and public health know-how. However, the increasing and complex difficulties of most health care delivery systems raise questions about the need for mechanisms for coordination at federal level, as well as about the equity and the effectiveness of the decentralized approach. The Swiss case shows that in a strongly decentralized system, health policy and strategy elaboration, as well as coordination mechanisms among the regional components of the system, are very hard to establish. This situation may lead to strong regional inequities in the financing of health care as well as to differences in the distribution of financial, human and material inputs into the health system. The study of the Swiss health system reveals also that, within a decentralized framework, the promotion of cost-effective interventions through a well-balanced approach towards promotional, preventive and curative services, or towards ambulatory and hospital care, is difficult to achieve, as agreements between relatively autonomous regions are difficult to obtain. Therefore, a decentralized system is not necessarily the most equitable and cost-effective way to deliver health care.

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

PubMed

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 (<50 copies/mL) and immunological success (CD4 gain ≥100 cells/µL), with type of care was investigated using multiple logistic regression. 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. 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.

Starting from Scratch: The Evolution of One University's Administrative Structure for Adult Programs

ERIC Educational Resources Information Center

Williams, Carol G.

2012-01-01

Abilene Christian University uses a hybrid governance model. Centralized structures include traditional program departments that supply the faculty and curriculum development for online graduate programs. Decentralized structures include an associate provost and separate student services for the online program.

Responsibility-Centered Management: A 10-Year Nursing Assessment.

ERIC Educational Resources Information Center

McBride, Angela Barron; Neiman, Sandra; Johnson, James

2000-01-01

Describes the implementation of responsibility-centered management, a decentralized model giving deans responsibility for expanding and using resources, at Indiana University's nursing school. Discusses how it led to creation of an information-rich environment, strategic decision making, and a performance-based reward structure. (SK)

About the development strategies of power plant in energy market

NASA Astrophysics Data System (ADS)

Duinea, Adelaida Mihaela

2017-12-01

The paper aims at identifying and assessing the revenues and costs incurred by various modernization and modernization-development strategies for a power plant in order to optimize the electric and thermal energy are produced and to conduct a sensitivity analysis of the main performance indicators. The Romanian energy system and the energy market have gone a long transition way, from the vertically integrated model, the responsibility for the delivery of the electricity comes exclusively to a state monopoly, to a decentralized system, characterized by the decentralization of production and transport, respectively distribution activities. Romania chose the liberal market model where the relations between the actors in the market - producers and suppliers free to make sales and purchase transactions for electrical energy - are mostly governed by contracts, which may be either bilaterally negotiated or are already regulated. Therefore, the importance of understanding the development trend of the Romanian energy market lies in its economic effects upon the solutions which could be adopted for the evolution of the cogeneration power plant in question.

Centralized vs. Decentralized Nursing Stations: An Evaluation of the Implications of Communication Technologies in Healthcare.

PubMed

Bayramzadeh, Sara; Alkazemi, Mariam F

2014-01-01

This study aims to explore the relationship between the nursing station design and use of communication technologies by comparing centralized and decentralized nursing stations. The rapid changes in communication technologies in healthcare are inevitable. Communication methods can change the way occupants use a space. In the meantime, decentralized nursing stations are emerging as a replacement for the traditional centralized nursing stations; however, not much research has been done on how the design of nursing stations can impact the use of communication technologies. A cross sectional study was conducted using an Internet-based survey among registered nurses in a Southeastern hospital in the United States. Two units with centralized nursing stations and two units with decentralized nursing stations were compared in terms of the application of communication technologies. A total of 70 registered nurses completed the survey in a 2-week period. The results revealed no significant differences between centralized and decentralized nursing stations in terms of frequency of communication technologies used. However, a difference was found between perception of nurses toward communication technologies and perceptions of the use of communication technologies in decentralized nursing stations. Although the study was limited to one hospital, the results indicate that nurses hold positive attitudes toward communication technologies. The results also reveal the strengths and weaknesses of each nursing station design with regard to communication technologies. Hospital, interdisciplinary, nursing, technology, work environment.

Anterior capsule contraction and intraocular lens decentration and tilt after hydrogel lens implantation

PubMed Central

Hayashi, K.; Hayashi, H.; Nakao, F.; Hayashi, F.

2001-01-01

AIM—To prospectively investigate changes in the area of the anterior capsule opening, and intraocular lens (IOL) decentration and tilt after implantation of a hydrogel IOL.
METHODS—100 patients underwent implantation of a hydrogel IOL in one eye and an acrylic IOL implantation in the opposite eye. The area of the anterior capsule opening, and the degree of IOL decentration and tilt were measured using the Scheimpflug videophotography system at 3 days, and at 1, 3, and 6 months postoperatively.
RESULTS—The mean anterior capsule opening area decreased significantly in both groups. At 6 months postoperatively, the area in the hydrogel group was significantly smaller than that in the acrylic group. The mean percentage of the area reduction in the hydrogel group was also significantly greater than that in the acrylic group, being 16.9% in the hydrogel group and 8.8% in the acrylic group. In contrast, IOL decentration and tilt did not progress in either group. No significant differences were found in the degree of IOL decentration and tilt throughout the follow up period.
CONCLUSIONS—Contraction of the anterior capsule opening was more extensive with the hydrogel IOL than with the acrylic IOL, but the degree of IOL decentration and tilt were similar for the two types of lenses studied.

 PMID:11673291

Fully decentralized control of a soft-bodied robot inspired by true slime mold.

PubMed

Umedachi, Takuya; Takeda, Koichi; Nakagaki, Toshiyuki; Kobayashi, Ryo; Ishiguro, Akio

2010-03-01

Animals exhibit astoundingly adaptive and supple locomotion under real world constraints. In order to endow robots with similar capabilities, we must implement many degrees of freedom, equivalent to animals, into the robots' bodies. For taming many degrees of freedom, the concept of autonomous decentralized control plays a pivotal role. However a systematic way of designing such autonomous decentralized control system is still missing. Aiming at understanding the principles that underlie animals' locomotion, we have focused on a true slime mold, a primitive living organism, and extracted a design scheme for autonomous decentralized control system. In order to validate this design scheme, this article presents a soft-bodied amoeboid robot inspired by the true slime mold. Significant features of this robot are twofold: (1) the robot has a truly soft and deformable body stemming from real-time tunable springs and protoplasm, the former is used for an outer skin of the body and the latter is to satisfy the law of conservation of mass; and (2) fully decentralized control using coupled oscillators with completely local sensory feedback mechanism is realized by exploiting the long-distance physical interaction between the body parts stemming from the law of conservation of protoplasmic mass. Simulation results show that this robot exhibits highly supple and adaptive locomotion without relying on any hierarchical structure. The results obtained are expected to shed new light on design methodology for autonomous decentralized control system.

High-energy laser tactical decision aid (HELTDA) for mission planning and predictive avoidance

NASA Astrophysics Data System (ADS)

Burley, Jarred L.; Fiorino, Steven T.; Randall, Robb M.; Bartell, Richard J.; Cusumano, Salvatore J.

2012-06-01

This study demonstrates the development of a high energy laser tactical decision aid (HELTDA) by the AFIT/CDE for mission planning High Energy Laser (HEL) weapon system engagements as well as centralized, decentralized, or hybrid predictive avoidance (CPA/DPA/HPA) assessments. Analyses of example HEL mission engagements are described as well as how mission planners are expected to employ the software. Example HEL engagement simulations are based on geographic location and recent/current atmospheric weather conditions. The atmospheric effects are defined through the AFIT/CDE Laser Environmental Effects Definition and Reference (LEEDR) model or the High Energy Laser End-to-End Operational Simulation (HELEEOS) model upon which the HELTDA is based. These models enable the creation of vertical profiles of temperature, pressure, water vapor content, optical turbulence, and atmospheric particulates and hydrometeors as they relate to line-by-line layer extinction coefficient magnitude at wavelengths from the UV to the RF. Seasonal and boundary layer variations (summer/winter) and time of day variations for a range of relative humidity percentile conditions are considered to determine optimum efficiency in a specific environment. Each atmospheric particulate/hydrometeor is evaluated based on its wavelength-dependent forward and off-axis scattering characteristics and absorption effects on the propagating environment to and beyond the target. In addition to realistic vertical profiles of molecular and aerosol absorption and scattering, correlated optical turbulence profiles in probabilistic (percentile) format are included. Numerical weather model forecasts are incorporated in the model to develop comprehensive understanding of HEL weapon system performance.

Organically Grown Architectures: Creating Decentralized, Autonomous Systems by Embryomorphic Engineering

NASA Astrophysics Data System (ADS)

Doursat, René

Exploding growth growth in computational systems forces us to gradually replace rigid design and control with decentralization and autonomy. Information technologies will progress, instead, by"meta-designing" mechanisms of system self-assembly, self-regulation and evolution. Nature offers a great variety of efficient complex systems, in which numerous small elements form large-scale, adaptive patterns. The new engineering challenge is to recreate this self-organization and let it freely generate innovative designs under guidance. This article presents an original model of artificial system growth inspired by embryogenesis. A virtual organism is a lattice of cells that proliferate, migrate and self-pattern into differentiated domains. Each cell's fate is controlled by an internal gene regulatory network network. Embryomorphic engineering emphasizes hyperdistributed architectures, and their development as a prerequisite of evolutionary design.

Patch Transporter: Incentivized, Decentralized Software Patch System for WSN and IoT Environments

PubMed Central

Lee, JongHyup

2018-01-01

In the complicated settings of WSN (Wireless Sensor Networks) and IoT (Internet of Things) environments, keeping a number of heterogeneous devices updated is a challenging job, especially with respect to effectively discovering target devices and rapidly delivering the software updates. In this paper, we convert the traditional software update process to a distributed service. We set an incentive system for faithfully transporting the patches to the recipient devices. The incentive system motivates independent, self-interested transporters for helping the devices to be updated. To ensure the system correctly operates, we employ the blockchain system that enforces the commitment in a decentralized manner. We also present a detailed specification for the proposed protocol and validate it by model checking and simulations for correctness. PMID:29438337

Patch Transporter: Incentivized, Decentralized Software Patch System for WSN and IoT Environments.

PubMed

Lee, JongHyup

2018-02-13

[-12]In the complicated settings of WSN (Wireless Sensor Networks) and IoT (Internet of Things) environments, keeping a number of heterogeneous devices updated is a challenging job, especially with respect to effectively discovering target devices and rapidly delivering the software updates. In this paper, we convert the traditional software update process to a distributed service. We set an incentive system for faithfully transporting the patches to the recipient devices. The incentive system motivates independent, self-interested transporters for helping the devices to be updated. To ensure the system correctly operates, we employ the blockchain system that enforces the commitment in a decentralized manner. We also present a detailed specification for the proposed protocol and validate it by model checking and simulations for correctness.

Decentralized PID controller for TITO systems using characteristic ratio assignment with an experimental application.

PubMed

Hajare, V D; Patre, B M

2015-11-01

This paper presents a decentralized PID controller design method for two input two output (TITO) systems with time delay using characteristic ratio assignment (CRA) method. The ability of CRA method to design controller for desired transient response has been explored for TITO systems. The design methodology uses an ideal decoupler to reduce the interaction. Each decoupled subsystem is reduced to first order plus dead time (FOPDT) model to design independent diagonal controllers. Based on specified overshoot and settling time, the controller parameters are computed using CRA method. To verify performance of the proposed controller, two benchmark simulation examples are presented. To demonstrate applicability of the proposed controller, experimentation is performed on real life interacting coupled tank level system. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

Robust detection-isolation-accommodation for sensor failures

NASA Technical Reports Server (NTRS)

Weiss, J. L.; Pattipati, K. R.; Willsky, A. S.; Eterno, J. S.; Crawford, J. T.

1985-01-01

The results of a one year study to: (1) develop a theory for Robust Failure Detection and Identification (FDI) in the presence of model uncertainty, (2) develop a design methodology which utilizes the robust FDI ththeory, (3) apply the methodology to a sensor FDI problem for the F-100 jet engine, and (4) demonstrate the application of the theory to the evaluation of alternative FDI schemes are presented. Theoretical results in statistical discrimination are used to evaluate the robustness of residual signals (or parity relations) in terms of their usefulness for FDI. Furthermore, optimally robust parity relations are derived through the optimization of robustness metrics. The result is viewed as decentralization of the FDI process. A general structure for decentralized FDI is proposed and robustness metrics are used for determining various parameters of the algorithm.

Basic principles of information technology organization in health care institutions.

PubMed

Mitchell, J A

1997-01-01

This paper focuses on the basic principles of information technology (IT) organization within health sciences centers. The paper considers the placement of the leader of the IT effort within the health sciences administrative structure and the organization of the IT unit. A case study of the University of Missouri-Columbia Health Sciences Center demonstrates how a role-based organizational model for IT support can be effective for determining the boundary between centralized and decentralized organizations. The conclusions are that the IT leader needs to be positioned with other institutional leaders who are making strategic decisions, and that the internal IT structure needs to be a role-based hybrid of centralized and decentralized units. The IT leader needs to understand the mission of the organization and actively use change-management techniques.

Current Models of Digital Scholarly Communication: Results of an Investigation Conducted by Ithaka for the Association of Research Libraries

ERIC Educational Resources Information Center

Maron, Nancy L.; Smith, K. Kirby

2008-01-01

As electronic resources for scholarship proliferate, more and more scholars turn to their computers rather than to print sources to conduct their research. The decentralized distribution of these new model works can make it difficult to fully appreciate their scope and number, even for university librarians tasked with knowing about valuable…

Decentralization, stabilization, and estimation of large-scale linear systems

NASA Technical Reports Server (NTRS)

Siljak, D. D.; Vukcevic, M. B.

1976-01-01

In this short paper we consider three closely related aspects of large-scale systems: decentralization, stabilization, and estimation. A method is proposed to decompose a large linear system into a number of interconnected subsystems with decentralized (scalar) inputs or outputs. The procedure is preliminary to the hierarchic stabilization and estimation of linear systems and is performed on the subsystem level. A multilevel control scheme based upon the decomposition-aggregation method is developed for stabilization of input-decentralized linear systems Local linear feedback controllers are used to stabilize each decoupled subsystem, while global linear feedback controllers are utilized to minimize the coupling effect among the subsystems. Systems stabilized by the method have a tolerance to a wide class of nonlinearities in subsystem coupling and high reliability with respect to structural perturbations. The proposed output-decentralization and stabilization schemes can be used directly to construct asymptotic state estimators for large linear systems on the subsystem level. The problem of dimensionality is resolved by constructing a number of low-order estimators, thus avoiding a design of a single estimator for the overall system.

Homophyly/kinship hypothesis: Natural communities, and predicting in networks

NASA Astrophysics Data System (ADS)

Li, Angsheng; Li, Jiankou; Pan, Yicheng

2015-02-01

It has been a longstanding challenge to understand natural communities in real world networks. We proposed a community finding algorithm based on fitness of networks, two algorithms for prediction, accurate prediction and confirmation of keywords for papers in the citation network Arxiv HEP-TH (high energy physics theory), and the measures of internal centrality, external de-centrality, internal and external slopes to characterize the structures of communities. We implemented our algorithms on 2 citation and 5 cooperation graphs. Our experiments explored and validated a homophyly/kinship principle of real world networks. The homophyly/kinship principle includes: (1) homophyly is the natural selection in real world networks, similar to Darwin's kinship selection in nature, (2) real world networks consist of natural communities generated by the natural selection of homophyly, (3) most individuals in a natural community share a short list of common attributes, (4) natural communities have an internal centrality (or internal heterogeneity) that a natural community has a few nodes dominating most of the individuals in the community, (5) natural communities have an external de-centrality (or external homogeneity) that external links of a natural community homogeneously distributed in different communities, and (6) natural communities of a given network have typical structures determined by the internal slopes, and have typical patterns of outgoing links determined by external slopes, etc. Our homophyly/kinship principle perfectly matches Darwin's observation that animals from ants to people form social groups in which most individuals work for the common good, and that kinship could encourage altruistic behavior. Our homophyly/kinship principle is the network version of Darwinian theory, and builds a bridge between Darwinian evolution and network science.

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

NASA Astrophysics Data System (ADS)

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.

Modeling Household Water Consumption in a Hydro-Institutional System - The Case of Jordan

NASA Astrophysics Data System (ADS)

Klassert, C. J. A.; Gawel, E.; Klauer, B.; Sigel, K.

2014-12-01

Jordan faces an archetypal combination of high water scarcity, with a per capita water availability of around 150 CM per year significantly below the absolute scarcity threshold of 500 CM, and strong population growth, especially due to the Syrian refugee crisis. This poses a severe challenge to the already strained institutions in the Jordanian water sector. The Stanford-led G8 Belmont Forum project "Integrated Analysis of Freshwater Resources Sustainability in Jordan" aims at analyzing the potential role of water sector institutions in the pursuit of a sustainable freshwater system performance. In order to do so, the project develops a coupled hydrological and agent-based model, allowing for the exploration of physical as well as socio-economic and institutional scenarios for Jordan's water sector. The part of this integrated model in focus here is the representation of household behavior in Jordan's densely populated capital Amman. Amman's piped water supply is highly intermittent, which also affects its potability. Therefore, Amman's citizens rely on various decentralized modes of supply, depending on their socio-economic characteristics. These include water storage in roof-top and basement tanks, private tanker supply, and the purchase of bottled water. Capturing this combination of centralized and decentralized supply modes is important for an adequate representation of water consumption behavior: Firstly, it will affect the impacts of supply-side and demand-side policies, such as reductions of non-revenue water (including illegal abstractions), the introduction of continuous supply, support for storage enhancements, and water tariff reforms. Secondly, it is also necessary to differentiate the impacts of any policy on the different socio-economic groups in Amman. In order to capture the above aspects of water supply, our model is based on the tiered supply curve approach, developed by Srinivasan et al. in 2011 to model a similar situation in Chennai, India. To tailor our model to the situation in Amman, we rely on sectoral data, existing literature analyses and expert discussions with Jordanian water sector representatives. Our modeling approach allows us to directly compare policies affecting both centralized and decentralized elements of the system within a common framework.

The institutionalization of River Basin Management as politics of scale - Insights from Mongolia

NASA Astrophysics Data System (ADS)

Houdret, Annabelle; Dombrowsky, Ines; Horlemann, Lena

2014-11-01

River Basin Management (RBM) as an approach to sustainable water use has become the dominant model of water governance. Its introduction, however, entails a fundamental realignment and rescaling of water-sector institutions along hydrological boundaries. Creating such a new governance scale is inherently political, and is being described as politics of scale. This paper analyzes how the politics of scale play out in the institutionalization of RBM in Mongolia. It furthermore scrutinizes the role of the broader political decentralization process in the introduction of RBM, an issue that has so far received little attention. Finally, it assesses whether the river basin is an adequate water management scale in Mongolia. This article finds that institutionalizing RBM in Mongolia is indeed a highly political negotiation process that does not only concern the choice of the governance scale, but also its detailed institutional design. It furthermore reveals that Mongolia's incomplete political decentralization process has for a long time negatively impacted the decentralization of water-related tasks and the implementation of RBM. However, the 2011 Budget Law and the 2012 Water Law provide for a fiscal strengthening of local governments and clearer sharing of responsibilities among the various different institutions involved in water management. Nevertheless, only if the 2012 Water Law is complemented by adequate by-laws - and if the newly created river basin institutions are adequately equipped - can RBM be effectively put into practice. This article confirms the usefulness of a politics-of-scale approach to understand scalar practices and changes in water management. However, the article also argues for a broadening of the analytical perspective to take the interdependencies between changes in water governance and other political processes, such as decentralization, into account.

The Sensitivity of Clinical Outcomes to Centration on the Light-Constricted Pupil for a Shape-Changing Corneal Inlay.

PubMed

Barragán-Garza, Enrique; Koch, Douglas D; Vargas, Luis G; Lang, Alan; Roy, Adam

2018-03-01

To assess the clinically acceptable range of inlay decentration with respect to the light-constricted pupil center and the coaxially sighted corneal light reflex (CSCLR) for an inlay (Raindrop Near Vision Inlay; ReVision Optics, Inc., Lake Forest, CA) that reshapes the anterior corneal surface. In this retrospective, observational cohort study of 115 patients with emmetropic or low hyperopic presbyopia who were implanted with a shape-changing corneal inlay, visual acuity, task performance (in good and dim light), reports of halos and glare, and satisfaction data were collected from the preoperative and 3-month postoperative examinations. Inlay centration with respect to the pupil center and CSCLR was determined from the center of the inlay effect derived from iTrace (Tracey Technologies, Houston, TX) wavefront measurements. Multivariate regression models assessed the influence of inlay position on visual outcomes. On average, monocular uncorrected near visual acuity (UNVA) improved 4.9 ± 1.7 lines in the treated eye, with no loss in binocular distance vision. Eighty-three percent of implants were centered radially within 0.5 mm of the pupil center. Multivariate analysis of decentration with respect to both the pupil center and CSCLR revealed no significant interaction with the above clinical outcomes, with the exception of UNVA in the treated eye (all P > .05, α = 0.05). For decentration of less than 0.75 mm, the change in UNVA was less than 1 line. Distance and near visual acuity, task performance, severity of halos and glare, and satisfaction were independent of radial decentration of the Raindrop Near Vision Inlay of less than 0.75 mm from the light-constricted pupil. [J Refract Surg. 2018;34(3):164-170.]. Copyright 2018, SLACK Incorporated.

Decentralization: Another Perspective

ERIC Educational Resources Information Center

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)

32 CFR Appendix B to Part 324 - System of Records Notice

Code of Federal Regulations, 2013 CFR

2013-07-01

... organizationally decentralized system, describe each level of organization or element that maintains a portion of... manager should be indicated. For geographically separated or organizationally decentralized activities...

32 CFR Appendix B to Part 324 - System of Records Notice

Code of Federal Regulations, 2011 CFR

2011-07-01

... organizationally decentralized system, describe each level of organization or element that maintains a portion of... manager should be indicated. For geographically separated or organizationally decentralized activities...

32 CFR Appendix B to Part 324 - System of Records Notice

Code of Federal Regulations, 2012 CFR

2012-07-01

... organizationally decentralized system, describe each level of organization or element that maintains a portion of... manager should be indicated. For geographically separated or organizationally decentralized activities...

32 CFR Appendix B to Part 324 - System of Records Notice

Code of Federal Regulations, 2014 CFR

2014-07-01

... organizationally decentralized system, describe each level of organization or element that maintains a portion of... manager should be indicated. For geographically separated or organizationally decentralized activities...

[Decentralization of psychiatric health service].

PubMed

Dabrowski, S

1996-01-01

The article discusses two stages of de-centralization of psychiatric hospitals: the first consists in further division into sub-districts, the second one includes successive establishment of psychiatric wards in general hospitals. With the growth of their number these wards are to take over more and more general psychiatric tasks from the specialized psychiatric hospitals. These wards will not substitute psychiatric hospitals completely. The hospitals, though decreasing in size and number, will be a necessary element of the de-centralized and versatile psychiatric care for a long time to come.

Monopolizing Sanctioning Power under Noise Eliminates Perverse Punishment But Does Not Increase Cooperation

PubMed Central

Fischer, Sven; Grechenig, Kristoffel; Meier, Nicolas

2016-01-01

We run several experiments which allow us to compare cooperation under perfect and imperfect information in a centralized and decentralized punishment regime. Under perfect and extremely noisy information, aggregate behavior does not differ between institutions. Under intermediate noise, punishment escalates in the decentralized peer-to-peer punishment regime which badly affects efficiency while sustaining cooperation for longer. Only decentralized punishment is often directed at cooperators (perverse punishment). We report several, sometimes subtle, differences in punishment behavior, and how contributions react. PMID:27746725

Pathogen Treatment Guidance and Monitoring Approaches fro On-Site Non-Potable Water Reuse

EPA Science Inventory

On-site non-potable water reuse is increasingly used to augment water supplies, but traditional fecal indicator approaches for defining and monitoring exposure risks are limited when applied to these decentralized options. This session emphasizes risk-based modeling to define pat...

The Use of Decentralized Control in the Design of a Large Segmented Space Reflector

NASA Technical Reports Server (NTRS)

Ryaciotaki-Boussalis, Helen; Mirmirani, Maj; Rad, Khosrow; Morales, Mauricio; Velazquez, Efrain; Chassiakos, Anastasios; Luzardo, Jose-Alberto

1997-01-01

The 3-dimensional model for a segmented reflector telescope is developed using finite element techniques. The structure is decomposed into six subsystems. System control design using neural networks is performed. Performance evaluation is demonstrated via simulation using PRO-MATLAB and SIMULINK.

How Is Open Source Special?

ERIC Educational Resources Information Center

Kapor, Mitchell

2005-01-01

Open source software projects involve the production of goods, but in software projects, the "goods" consist of information. The open source model is an alternative to the conventional centralized, command-and-control way in which things are usually made. In contrast, open source projects are genuinely decentralized and transparent. Transparent…

An Academic Literacies Argument for Decentralizing EAP Provision

ERIC Educational Resources Information Center

Murray, Neil

2016-01-01

English-medium universities have generally adopted centralized models of in-sessional English language provision, where expertise resides and is often delivered within language development units or as part of larger cognate departments, typically TESOL or Applied Linguistics departments. This arrangement might be seen as reflecting a…

Northeastern Illinois RTA Decentralized Paratransit Brokerage Program

DOT National Transportation Integrated Search

1982-09-01

This document presents a review and assessment of the Northeastern Illinois Regional Transportation Authority's (RTA) Paratransit Brokerage Demonstration Program which involved six projects implemented by local governments under RTA's decentralized b...

Programs Related to Septic Systems

EPA Pesticide Factsheets

There are many programs, both at the EPA and elsewhere, that relate to the decentralized wastewater program and provide information about how decentralized wastewater is integrated in environmental quality, planning, protection, and conservation.

20 CFR 375.7 - Operating regulations.

Code of Federal Regulations, 2012 CFR

2012-04-01

... offices. (2) To provide the necessary authority for a decentralized program as outlined in this paragraph...) To provide the necessary authority for a decentralized program as outlined in paragraph (b) of this...

20 CFR 375.7 - Operating regulations.

Code of Federal Regulations, 2013 CFR

2013-04-01

... offices. (2) To provide the necessary authority for a decentralized program as outlined in this paragraph...) To provide the necessary authority for a decentralized program as outlined in paragraph (b) of this...

20 CFR 375.7 - Operating regulations.

Code of Federal Regulations, 2014 CFR

2014-04-01

... offices. (2) To provide the necessary authority for a decentralized program as outlined in this paragraph...) To provide the necessary authority for a decentralized program as outlined in paragraph (b) of this...

A Closed-Loop Hardware Simulation of Decentralized Satellite Formation Control

NASA Technical Reports Server (NTRS)

Ebimuma, Takuji; Lightsey, E. Glenn; Baur, Frank (Technical Monitor)

2002-01-01

In recent years, there has been significant interest in the use of formation flying spacecraft for a variety of earth and space science missions. Formation flying may provide smaller and cheaper satellites that, working together, have more capability than larger and more expensive satellites. Several decentralized architectures have been proposed for autonomous establishment and maintenance of satellite formations. In such architectures, each satellite cooperatively maintains the shape of the formation without a central supervisor, and processing only local measurement information. The Global Positioning System (GPS) sensors are ideally suited to provide such local position and velocity measurements to the individual satellites. An investigation of the feasibility of a decentralized approach to satellite formation flying was originally presented by Carpenter. He extended a decentralized linear-quadratic-Gaussian (LQG) framework proposed by Speyer in a fashion similar to an extended Kalman filter (EKE) which processed GPS position fix solutions. The new decentralized LQG architecture was demonstrated in a numerical simulation for a realistic scenario that is similar to missions that have been proposed by NASA and the U.S. Air Force. Another decentralized architecture was proposed by Park et al. using carrier differential-phase GPS (CDGPS). Recently, Busse et al demonstrated the decentralized CDGPS architecture in a hardware-in-the-loop simulation on the Formation Flying TestBed (FFTB) at Goddard Space Flight Center (GSFC), which features two Spirent Cox 16 channel GPS signal generator. Although representing a step forward by utilizing GPS signal simulators for a spacecraft formation flying simulation, only an open-loop performance, in which no maneuvers were executed based on the real-time state estimates, was considered. In this research, hardware experimentation has been extended to include closed-loop integrated guidance and navigation of multiple spacecraft formations using GPS receivers and real-time vehicle telemetry. A hardware closed-loop simulation has been performed using the decentralized LQG architecture proposed by Carpenter in the GPS test facility at the Center for Space Research (CSR). This is the first presentation using this type of hardware for demonstration of closed-loop spacecraft formation flying.

Comparison of Centralized-Manual, Centralized-Computerized, and Decentralized-Computerized Order and Management Information Models for the Turkish Air Force Logistics System.

DTIC Science & Technology

1986-09-01

differentiation between the systems. This study will investigate an appropriate Order Processing and Management Information System (OP&MIS) to link base-level...methodology: 1. Reviewed the current order processing and information model of the TUAF Logistics System. (centralized-manual model) 2. Described the...RDS program’s order processing and information system. (centralized-computerized model) 3. Described the order irocessing and information system of

The Scale Effects of Engineered Inlets in Urban Hydrologic Processes

NASA Astrophysics Data System (ADS)

Shevade, L.; Montalto, F. A.

2017-12-01

Runoff from urban surfaces is typically captured by engineered inlets for conveyance to receiving water bodies or treatment plants. Normative hydrologic and hydraulic (H&H) modeling tools generally assume 100% efficient inlets, though observations by the authors suggest this assumption is invalid. The discrepancy is key since the more efficiently the inlet, the more linearly hydrologic processes scale with catchment area. Using several years of remote sensing, the observed efficiencies of urban green infrastructure (GI) facility inlets in New York City are presented, as a function of the morphological and climatological properties of their catchments and events. The rainfall-runoff response is modeled with EPA to assess the degree of inaccuracy that the assumption of efficient inlets introduces in block and neighborhood-scale simulations. Next, an algorithm is presented that incorporates inlet efficiency into SWMM and the improved predictive skill evaluated using Nash-Sutcliffe and root-mean-square error (RMSE). The results are used to evaluate the extent to which decentralized green stormwater management facilities positioned at the low points of urban catchments ought to be designed with larger capacities than their counterparts located further upslope.

Growing and navigating the small world Web by local content

PubMed Central

Menczer, Filippo

2002-01-01

Can we model the scale-free distribution of Web hypertext degree under realistic assumptions about the behavior of page authors? Can a Web crawler efficiently locate an unknown relevant page? These questions are receiving much attention due to their potential impact for understanding the structure of the Web and for building better search engines. Here I investigate the connection between the linkage and content topology of Web pages. The relationship between a text-induced distance metric and a link-based neighborhood probability distribution displays a phase transition between a region where linkage is not determined by content and one where linkage decays according to a power law. This relationship is used to propose a Web growth model that is shown to accurately predict the distribution of Web page degree, based on textual content and assuming only local knowledge of degree for existing pages. A qualitatively similar phase transition is found between linkage and semantic distance, with an exponential decay tail. Both relationships suggest that efficient paths can be discovered by decentralized Web navigation algorithms based on textual and/or categorical cues. PMID:12381792

Growing and navigating the small world Web by local content

NASA Astrophysics Data System (ADS)

Menczer, Filippo

2002-10-01

Can we model the scale-free distribution of Web hypertext degree under realistic assumptions about the behavior of page authors? Can a Web crawler efficiently locate an unknown relevant page? These questions are receiving much attention due to their potential impact for understanding the structure of the Web and for building better search engines. Here I investigate the connection between the linkage and content topology of Web pages. The relationship between a text-induced distance metric and a link-based neighborhood probability distribution displays a phase transition between a region where linkage is not determined by content and one where linkage decays according to a power law. This relationship is used to propose a Web growth model that is shown to accurately predict the distribution of Web page degree, based on textual content and assuming only local knowledge of degree for existing pages. A qualitatively similar phase transition is found between linkage and semantic distance, with an exponential decay tail. Both relationships suggest that efficient paths can be discovered by decentralized Web navigation algorithms based on textual and/or categorical cues.

Growing and navigating the small world Web by local content.

PubMed

Menczer, Filippo

2002-10-29

Can we model the scale-free distribution of Web hypertext degree under realistic assumptions about the behavior of page authors? Can a Web crawler efficiently locate an unknown relevant page? These questions are receiving much attention due to their potential impact for understanding the structure of the Web and for building better search engines. Here I investigate the connection between the linkage and content topology of Web pages. The relationship between a text-induced distance metric and a link-based neighborhood probability distribution displays a phase transition between a region where linkage is not determined by content and one where linkage decays according to a power law. This relationship is used to propose a Web growth model that is shown to accurately predict the distribution of Web page degree, based on textual content and assuming only local knowledge of degree for existing pages. A qualitatively similar phase transition is found between linkage and semantic distance, with an exponential decay tail. Both relationships suggest that efficient paths can be discovered by decentralized Web navigation algorithms based on textual and/or categorical cues.

Decision and coordination of low-carbon supply chain considering technological spillover and environmental awareness.

PubMed

Xu, Lang; Wang, Chuanxu; Li, Hui

2017-06-08

We focus on the impacts of technological spillovers and environmental awareness in a two-echelon supply chain with one-single supplier and one-single manufacturer to reduce carbon emission. In this supply chain, carbon abatement investment becomes one of key factors of cutting costs and improving profits, which is reducing production costs in the components and products-the investment from players in supply chain. On the basis of optimality theory, the centralized and decentralized models are respectively established to investigate the optimal decisions and profits. Further, setting the players' profits of the decentralized scenario as the disagreement points, we propose a bargaining-coordination contract through revenue-cost sharing to enhance the performance. Finally, by theoretical comparison and numerical analysis, the results show that: (i) The optimal profits of players and supply chain improve as technological spillovers and environmental awareness increase, and the profits of them in the bargaining-coordination contract are higher than that in the decentralized scenario; (ii) Technological spillovers between the players amplify the impact of "free-ride" behavior, in which the supplier always incentives the manufacturer to improve carbon emission intensity, but the cooperation will achieves and the profits will improve only when technological spillovers and environmental awareness are great; (iii) The contract can effectively achieve coordinated supply chain, and improve carbon abatement investment.

Optical aberrations induced by subclinical decentrations of the ablation pattern

NASA Astrophysics Data System (ADS)

Mrochen, Michael; Kaemmerer, Maik; Riedel, Peter; Mierdel, Peter; Krinke, Hans-Eberhard; Seiler, Theo

2000-06-01

Purpose: The aim of this work was to study the effect of currently used ablation profiles along with eccentric ablations on the increase of higher order aberrations observed after PRK. Material and Methods: The optical aberrations of 10 eyes were tested before and after PRK. Refractive surgery was performed using a ArF-excimer laser system. In all cases, the ablation zone was 6 mm or larger. The spherical equivalent of the correction was ranging from -2.5 D to -6.0 D. The measured wavefront error was compared to numerical simulations done with the reduced eye model and currently used ablation profiles as well as compared with experimental results obtained from ablation on PMMA balls. Results: The aberration measurements result in a considerable change of the spherical- and coma-like wavefront errors. This result was in good correlation with the numerical simulations and the experimental results. Furthermore, it has been derived that the major contribution on the induced higher order aberrations are a result of the small decentration (less than 1.0 mm) of the ablation zone. Conclusions: Higher order spherical- and coma-like aberrations after PRK are mainly determined by the decentration of the ablation zone during laser refractive surgery. However, future laser systems should use efficient eye-tracking systems and aspherical ablation profiles to overcome this problem.

Two retailer-supplier supply chain models with default risk under trade credit policy.

PubMed

Wu, Chengfeng; Zhao, Qiuhong

2016-01-01

The purpose of the paper is to formulate two uncooperative replenishment models with demand and default risk which are the functions of the trade credit period, i.e., a Nash equilibrium model and a supplier-Stackelberg model. Firstly, we present the optimal results of decentralized decision and centralized decision without trade credit. Secondly, we derive the existence and uniqueness conditions of the optimal solutions under the two games, respectively. Moreover, we present a set of theorems and corollary to determine the optimal solutions. Finally, we provide an example and sensitivity analysis to illustrate the proposed strategy and optimal solutions. Sensitivity analysis reveals that the total profits of supply chain under the two games both are better than the results under the centralized decision only if the optimal trade credit period isn't too short. It also reveals that the size of trade credit period, demand, retailer's profit and supplier's profit have strong relationship with the increasing demand coefficient, wholesale price, default risk coefficient and production cost. The major contribution of the paper is that we comprehensively compare between the results of decentralized decision and centralized decision without trade credit, Nash equilibrium and supplier-Stackelberg models with trade credit, and obtain some interesting managerial insights and practical implications.

A Behavioral Model of Landscape Change in the Amazon Basin: The Colonist Case

NASA Technical Reports Server (NTRS)

Walker, R. A.; Drzyzga, S. A.; Li, Y. L.; Wi, J. G.; Caldas, M.; Arima, E.; Vergara, D.

2004-01-01

This paper presents the prototype of a predictive model capable of describing both magnitudes of deforestation and its spatial articulation into patterns of forest fragmentation. In a departure from other landscape models, it establishes an explicit behavioral foundation for algorithm development, predicated on notions of the peasant economy and on household production theory. It takes a 'bottom-up' approach, generating the process of land-cover change occurring at lot level together with the geography of a transportation system to describe regional landscape change. In other words, it translates the decentralized decisions of individual households into a collective, spatial impact. In so doing, the model unites the richness of survey research on farm households with the analytical rigor of spatial analysis enabled by geographic information systems (GIs). The paper describes earlier efforts at spatial modeling, provides a critique of the so-called spatially explicit model, and elaborates a behavioral foundation by considering farm practices of colonists in the Amazon basin. It then uses, insight from the behavioral statement to motivate a GIs-based model architecture. The model is implemented for a long-standing colonization frontier in the eastern sector of the basin, along the Trans-Amazon Highway in the State of Para, Brazil. Results are subjected to both sensitivity analysis and error assessment, and suggestions are made about how the model could be improved.

Cost comparison of centralized and decentralized wastewater management systems using optimization model.

PubMed

Jung, Youngmee Tiffany; Narayanan, N C; Cheng, Yu-Ling

2018-05-01

There is a growing interest in decentralized wastewater management (DWWM) as a potential alternative to centralized wastewater management (CWWM) in developing countries. However, the comparative cost of CWWM and DWWM is not well understood. In this study, the cost of cluster-type DWWM is simulated and compared to the cost of CWWM in Alibag, India. A three-step model is built to simulate a broad range of potential DWWM configurations with varying number and layout of cluster subsystems. The considered DWWM scheme consists of cluster subsystems, that each uses simplified sewer and DEWATS (Decentralized Wastewater Treatment Systems). We consider CWWM that uses conventional sewer and an activated sludge plant. The results show that the cost of DWWM can vary significantly with the number and layout of the comprising cluster subsystems. The cost of DWWM increased nonlinearly with increasing number of comprising clusters, mainly due to the loss in the economies of scale for DEWATS. For configurations with the same number of comprising cluster subsystems, the cost of DWWM varied by ±5% around the mean, depending on the layout of the cluster subsystems. In comparison to CWWM, DWWM was of lower cost than CWWM when configured with fewer than 16 clusters in Alibag, with significantly less operation and maintenance requirement, but with higher capital and land requirement for construction. The study demonstrates that cluster-type DWWM using simplified sewer and DEWATS may be a cost-competitive alternative to CWWM, when carefully configured to lower the cost. Copyright © 2018 Elsevier Ltd. All rights reserved.

Distributed resource allocation under communication constraints

NASA Astrophysics Data System (ADS)

Dodin, Pierre; Nimier, Vincent

2001-03-01

This paper deals with a study of the multi-sensor management problem for multi-target tracking. The collaboration between many sensors observing the same target means that they are able to fuse their data during the information process. Then one must take into account this possibility to compute the optimal association sensors-target at each step of time. In order to solve this problem for real large scale system, one must both consider the information aspect and the control aspect of the problem. To unify these problems, one possibility is to use a decentralized filtering algorithm locally driven by an assignment algorithm. The decentralized filtering algorithm we use in our model is the filtering algorithm of Grime, which relaxes the usual full-connected hypothesis. By full-connected, one means that the information in a full-connected system is totally distributed everywhere at the same moment, which is unacceptable for a real large scale system. We modelize the distributed assignment decision with the help of a greedy algorithm. Each sensor performs a global optimization, in order to estimate other information sets. A consequence of the relaxation of the full- connected hypothesis is that the sensors' information set are not the same at each step of time, producing an information dis- symmetry in the system. The assignment algorithm uses a local knowledge of this dis-symmetry. By testing the reactions and the coherence of the local assignment decisions of our system, against maneuvering targets, we show that it is still possible to manage with decentralized assignment control even though the system is not full-connected.

Papers by the Decentralized Wastewater Management MOU Partnership

EPA Pesticide Factsheets

Four position papers for state, local, and tribal government officials and interested stakeholders. These papers include information on the uses and benefits of decentralized wastewater treatment and examples of its effective use.

Clean Water State Revolving Fund (CWSRF): Decentralized Wastewater Treatment

EPA Pesticide Factsheets

Decentralized wastewater treatment is an onsite or clustered system used to collect, treat, and disperse or reclaim wastewater from a small community or service area (e.g., septic systems, cluster systems, lagoons).

Experimental Verification of Fully Decentralized Control Inspired by Plasmodium of True Slime Mold

NASA Astrophysics Data System (ADS)

Umedachi, Takuya; Takeda, Koichi; Nakagaki, Toshiyuki; Kobayashi, Ryo; Ishiguro, Akio

This paper presents a fully decentralized control inspired by plasmodium of true slime mold and its validity using a soft-bodied amoeboid robot. The notable features of this paper are twofold: (1) the robot has truly soft and deformable body stemming from real-time tunable springs and a balloon, the former is utilized as an outer skin of the body and the latter serves as protoplasm; and (2) a fully decentralized control using coupled oscillators with completely local sensory feedback mechanism is realized by exploiting the long-distance physical interaction between the body parts induced by the law of conservation of protoplasmic mass. Experimental results show that this robot exhibits truly supple locomotion without relying on any hierarchical structure. The results obtained are expected to shed new light on design scheme for autonomous decentralized control system.

Library and Information Networks: Centralization and Decentralization.

ERIC Educational Resources Information Center

Segal, JoAnn S.

1988-01-01

Describes the development of centralized library networks and the current factors that make library sharing on a smaller scale feasible. The discussion covers the need to decide the level at which library cooperation should occur and the possibility of linking via the Open System Interface Reference Model. (37 references) (CLB)

A Coordinated Decentralized Approach to Online Project Development

ERIC Educational Resources Information Center

Mykota, David

2013-01-01

With the growth rate of online learning outpacing traditional face-to-face instruction, universities are beginning to recognize the importance of strategic planning in its development. Making the case for online learning requires sound project management practices and an understanding of the business models on which it is predicated. The objective…

Educating Democracy: The Role of Systemic Leadership.

ERIC Educational Resources Information Center

Crow, Gary M.; Slater, Robert O.

This monograph explores the notion of viewing leadership as a single, interconnecting system at work in the internal and external school environment, rather than as a collection of individual roles. The document explores what the new leadership paradigm--a decentralized, collaborative model--means to schools. Leadership is viewed as an…

Modeling, Analysis, and Control of a Hypersonic Vehicle with Significant Aero-Thermo-Elastic-Propulsion Interactions: Elastic, Thermal and Mass Uncertainty

NASA Astrophysics Data System (ADS)

Khatri, Jaidev

This thesis examines themodeling, analysis, and control system design issues for scramjet powered hypersonic vehicles. A nonlinear three degrees of freedom longitudinal model which includes aero-propulsion-elasticity effects was used for all analyses. This model is based upon classical compressible flow and Euler-Bernouli structural concepts. Higher fidelity computational fluid dynamics and finite element methods are needed for more precise intermediate and final evaluations. The methods presented within this thesis were shown to be useful for guiding initial control relevant design. The model was used to examine the vehicle's static and dynamic characteristics over the vehicle's trimmable region. The vehicle has significant longitudinal coupling between the fuel equivalency ratio (FER) and the flight path angle (FPA). For control system design, a two-input two-output plant (FER - elevator to speed-FPA) with 11 states (including 3 flexible modes) was used. Velocity, FPA, and pitch were assumed to be available for feedback. Aerodynamic heat modeling and design for the assumed TPS was incorporated to original Bolender's model to study the change in static and dynamic properties. De-centralized control stability, feasibility and limitations issues were dealt with the change in TPS elasticity, mass and physical dimension. The impact of elasticity due to TPS mass, TPS physical dimension as well as prolonged heating was also analyzed to understand performance limitations of de-centralized control designed for nominal model.

Safety and Convergence Analysis of Intersecting Aircraft Flows Under Decentralized Collision Avoidance

NASA Astrophysics Data System (ADS)

Dallal, Ahmed H.

Safety is an essential requirement for air traffic management and control systems. Aircraft are not allowed to get closer to each other than a specified safety distance, to avoid any conflicts and collisions between aircraft. Forecast analysis predicts a tremendous increase in the number of flights. Subsequently, automated tools are needed to help air traffic controllers resolve air born conflicts. In this dissertation, we consider the problem of conflict resolution of aircraft flows with the assumption that aircraft are flowing through a fixed specified control volume at a constant speed. In this regard, several centralized and decentralized resolution rules have been proposed for path planning and conflict avoidance. For the case of two intersecting flows, we introduce the concept of conflict touches, and a collaborative decentralized conflict resolution rule is then proposed and analyzed for two intersecting flows. The proposed rule is also able to resolved airborne conflicts that resulted from resolving another conflict via the domino effect. We study the safety conditions under the proposed conflict resolution and collision avoidance rule. Then, we use Lyapunov analysis to analytically prove the convergence of conflict resolution dynamics under the proposed rule. The analysis show that, under the proposed conflict resolution rule, the system of intersecting aircraft flows is guaranteed to converge to safe, conflict free, trajectories within a bounded time. Simulations are provided to verify the analytically derived conclusions and study the convergence of the conflict resolution dynamics at different encounter angles. Simulation results show that lateral deviations taken by aircraft in each flow, to resolve conflicts, are bounded, and aircraft converged to safe and conflict free trajectories, within a finite time.

Financing indicators for health care decentralization in Latin America: information and suggestions for health planning.

PubMed

Arredondo, A; Parada, I

2001-01-01

This article presents the results from an evaluative longitudinal study with before-after design. The main objective was to determine the effects of health care decentralization on changes in health financing. Taking into account feasibility, political and technical criteria, three Latin American countries were selected as study populations: Mexico, Nicaragua and Peru. The methodology had two main phases. In the first phase, the study referred to secondary sources of data and documents to obtain information about the following variables: type of decentralization implemented, source of finance, funds of financing, providers, final use of resources and mechanisms for resource allocation. In the second phase, the study referred to primary data collected in a survey of key personnel from the health sectors of each country. Taking into account the changes implemented in the three countries, as well as the strengths and weaknesses of each country in financing and decentralization, a rule for decision-making is proposed that attempts to identify the main financial changes implemented in each country and the basic indicators that can be used in future years to direct the planning, assessment, adjustment and correction of health financing and decentralization.

Towards a Decentralized Magnetic Indoor Positioning System

PubMed Central

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

Towards a Decentralized Magnetic Indoor Positioning System.

PubMed

Kasmi, Zakaria; Norrdine, Abdelmoumen; Blankenbach, Jörg

2015-12-04

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.

32 CFR Appendix F to Part 505 - Example of a System of Records Notice

Code of Federal Regulations, 2012 CFR

2012-07-01

...) System Location: Specify the address of the primary system and any decentralized elements, including... title and duty address of the system manager. For decentralized systems, show the locations, the...

32 CFR Appendix F to Part 505 - Example of a System of Records Notice

Code of Federal Regulations, 2014 CFR

2014-07-01

...) System Location: Specify the address of the primary system and any decentralized elements, including... title and duty address of the system manager. For decentralized systems, show the locations, the...

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

NASA Technical Reports Server (NTRS)

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.

On decentralized control of large-scale systems

NASA Technical Reports Server (NTRS)

Siljak, D. D.

1978-01-01

A scheme is presented for decentralized control of large-scale linear systems which are composed of a number of interconnected subsystems. By ignoring the interconnections, local feedback controls are chosen to optimize each decoupled subsystem. Conditions are provided to establish compatibility of the individual local controllers and achieve stability of the overall system. Besides computational simplifications, the scheme is attractive because of its structural features and the fact that it produces a robust decentralized regulator for large dynamic systems, which can tolerate a wide range of nonlinearities and perturbations among the subsystems.

Decentralized control of the COFS-I Mast using linear dc motors

NASA Technical Reports Server (NTRS)

Lindner, Douglas K.; Celano, Tom; Ide, Eric

1989-01-01

Consideration is given to a decentralized control design for vibration suppression in the COFS-I Mast using linear dc motors for actuators. The decentralized control design is based results from power systems using root locus techniques that are not well known. The approach is effective because the loop gain is low due to low actuator authority. The frequency-dependent nonlinearities of the actuator are taken into account. Because of the tendency of the transients to saturate the the stroke length of the actuator, its effectiveness is limited.

Assessment of tilt and decentration of crystalline lens and intraocular lens relative to the corneal topographic axis using anterior segment optical coherence tomography

PubMed Central

Morizane, Yuki; Shiode, Yusuke; Hirano, Masayuki; Doi, Shinichiro; Toshima, Shinji; Fujiwara, Atsushi; Shiraga, Fumio

2017-01-01

Purpose To investigate the tilt and decentration of the crystalline lens and the intraocular lens (IOL) relative to the corneal topographic axis using anterior segment ocular coherence tomography (AS-OCT). Methods A sample set of 100 eyes from 49 subjects (41 eyes with crystalline lenses and 59 eyes with IOLs) were imaged using second generation AS-OCT (CASIA2, TOMEY) in June and July 2016 at Okayama University. Both mydriatic and non-mydriatic images were obtained, and the tilt and decentration of the crystalline lens and the IOL were quantified. The effects of pupil dilation on measurements were also assessed. Results The crystalline lens showed an average tilt of 5.15° towards the inferotemporal direction relative to the corneal topographic axis under non-mydriatic conditions and 5.25° under mydriatic conditions. Additionally, an average decentration of 0.11 mm towards the temporal direction was observed under non-mydriatic conditions and 0.08 mm under mydriatic conditions. The average tilt for the IOL was 4.31° towards the inferotemporal direction relative to the corneal topographic axis under non-mydriatic conditions and 4.65° in the same direction under mydriatic conditions. The average decentration was 0.05 mm towards the temporal direction under non-mydriatic conditions and 0.08 mm in the same direction under mydriatic conditions. A strong correlation was found between the average tilt and decentration values of the crystalline lens and the IOL under both non-mydriatic and mydriatic conditions (all Spearman correlation coefficients, r ≥ 0.800; all P < 0.001). Conclusion When measured using second generation AS-OCT, both the crystalline lens and the IOL showed an average tilt of 4–6° toward the inferotemporal direction relative to the corneal topographic axis and an average decentration of less than 0.12 mm towards the temporal direction. These results were not influenced by pupil dilation and they showed good repeatability. PMID:28863141

Assessment of tilt and decentration of crystalline lens and intraocular lens relative to the corneal topographic axis using anterior segment optical coherence tomography.

PubMed

Kimura, Shuhei; Morizane, Yuki; Shiode, Yusuke; Hirano, Masayuki; Doi, Shinichiro; Toshima, Shinji; Fujiwara, Atsushi; Shiraga, Fumio

2017-01-01

To investigate the tilt and decentration of the crystalline lens and the intraocular lens (IOL) relative to the corneal topographic axis using anterior segment ocular coherence tomography (AS-OCT). A sample set of 100 eyes from 49 subjects (41 eyes with crystalline lenses and 59 eyes with IOLs) were imaged using second generation AS-OCT (CASIA2, TOMEY) in June and July 2016 at Okayama University. Both mydriatic and non-mydriatic images were obtained, and the tilt and decentration of the crystalline lens and the IOL were quantified. The effects of pupil dilation on measurements were also assessed. The crystalline lens showed an average tilt of 5.15° towards the inferotemporal direction relative to the corneal topographic axis under non-mydriatic conditions and 5.25° under mydriatic conditions. Additionally, an average decentration of 0.11 mm towards the temporal direction was observed under non-mydriatic conditions and 0.08 mm under mydriatic conditions. The average tilt for the IOL was 4.31° towards the inferotemporal direction relative to the corneal topographic axis under non-mydriatic conditions and 4.65° in the same direction under mydriatic conditions. The average decentration was 0.05 mm towards the temporal direction under non-mydriatic conditions and 0.08 mm in the same direction under mydriatic conditions. A strong correlation was found between the average tilt and decentration values of the crystalline lens and the IOL under both non-mydriatic and mydriatic conditions (all Spearman correlation coefficients, r ≥ 0.800; all P < 0.001). When measured using second generation AS-OCT, both the crystalline lens and the IOL showed an average tilt of 4-6° toward the inferotemporal direction relative to the corneal topographic axis and an average decentration of less than 0.12 mm towards the temporal direction. These results were not influenced by pupil dilation and they showed good repeatability.

Treatment Initiation, Program Attrition and Patient Treatment Outcomes Associated with Scale-Up and Decentralization of HIV Care in Rural Malawi

PubMed Central

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

2012-01-01

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. PMID:23077473

EVALUATION OF ECONOMIC INCENTIVES FOR DECENTRALIZED STORMWATER RUNOFF MANAGEMENT

EPA Science Inventory

Impervious surfaces in urban and suburban areas can lead to excess stormwater runoff throughout a watershed, typically resulting in widespread hydrologic and ecological alteration of receiving streams. Decentralized stormwater management may improve stream ecosystems by reducing ...

Engaging Social Capital for Decentralized Urban Stormwater Management

EPA Science Inventory

Decentralized approaches to urban stormwater management, whereby installations of green infrastructure (e.g., rain gardens, bioswales, and constructed wetlands) are dispersed throughout a management area, are cost-effective solutions with co-benefits beyond water abatement. Inste...

A Decentralized Eigenvalue Computation Method for Spectrum Sensing Based on Average Consensus

NASA Astrophysics Data System (ADS)

Mohammadi, Jafar; Limmer, Steffen; Stańczak, Sławomir

2016-07-01

This paper considers eigenvalue estimation for the decentralized inference problem for spectrum sensing. We propose a decentralized eigenvalue computation algorithm based on the power method, which is referred to as generalized power method GPM; it is capable of estimating the eigenvalues of a given covariance matrix under certain conditions. Furthermore, we have developed a decentralized implementation of GPM by splitting the iterative operations into local and global computation tasks. The global tasks require data exchange to be performed among the nodes. For this task, we apply an average consensus algorithm to efficiently perform the global computations. As a special case, we consider a structured graph that is a tree with clusters of nodes at its leaves. For an accelerated distributed implementation, we propose to use computation over multiple access channel (CoMAC) as a building block of the algorithm. Numerical simulations are provided to illustrate the performance of the two algorithms.

Resource allocation and budgetary mechanisms for decentralized health systems: experiences from Balochistan, Pakistan.

PubMed

Green, A; Ali, B; Naeem, A; Ross, D

2000-01-01

This paper identifies key political and technical issues involved in the development of an appropriate resource allocation and budgetary system for the public health sector, using experience gained in the Province of Balochistan, Pakistan. The resource allocation and budgetary system is a critical, yet often neglected, component of any decentralization policy. Current systems are often based on historical incrementalism that is neither efficient nor equitable. This article describes technical work carried out in Balochistan to develop a system of resource allocation and budgeting that is needs-based, in line with policies of decentralization, and implementable within existing technical constraints. However, the development of technical systems, while necessary, is not a sufficient condition for the implementation of a resource allocation and decentralized budgeting system. This is illustrated by analysing the constraints that have been encountered in the development of such a system in Balochistan.

Resource allocation and budgetary mechanisms for decentralized health systems: experiences from Balochistan, Pakistan.

PubMed Central

Green, A.; Ali, B.; Naeem, A.; Ross, D.

2000-01-01

This paper identifies key political and technical issues involved in the development of an appropriate resource allocation and budgetary system for the public health sector, using experience gained in the Province of Balochistan, Pakistan. The resource allocation and budgetary system is a critical, yet often neglected, component of any decentralization policy. Current systems are often based on historical incrementalism that is neither efficient nor equitable. This article describes technical work carried out in Balochistan to develop a system of resource allocation and budgeting that is needs-based, in line with policies of decentralization, and implementable within existing technical constraints. However, the development of technical systems, while necessary, is not a sufficient condition for the implementation of a resource allocation and decentralized budgeting system. This is illustrated by analysing the constraints that have been encountered in the development of such a system in Balochistan. PMID:10994286

Adaptive model of the aging emmetropic eye and its changes with accommodation.

PubMed

Navarro, Rafael

2014-11-20

A general schematic model of the optical system of the emmetropic human eye is proposed, capable of adapting to changes with age and accommodation through adjustment of the optical surfaces and the internal gradient index structure of the lens. The specific models of the cornea and lens consist of minor generalizations of previous work by assuming them to be the sum of a biconic plus three higher order Zernike modes. The internal gradient index distribution adapts to the external shape so that the analytical expression is invariant with the changes with age and accommodation. The model also includes tips, tilts, and decentrations of the surfaces according to experimental findings. The specific parameters of these models are either constants or functions of age and/or accommodation. The model is polychromatic, and its optical performance was evaluated along the keratometric axis. Chromatic aberrations (longitudinal and transverse), astigmatism, coma, trefoil, and spherical aberration show good agreement with experimental averages. The change of these aberrations as a function of age or accommodation is also consistent with experimental findings (except for trefoil in eyes older than 50 years). This means that the average structure seems to predict the average performance. Nevertheless, the present model is too schematic to account for other higher order aberrations, such as tetrafoil, also present in real eyes. © 2014 ARVO.

Decentralizing conservation and diversifying livelihoods within Kanchenjunga Conservation Area, Nepal.

PubMed

Parker, Pete; Thapa, Brijesh; Jacob, Aerin

2015-12-01

To alleviate poverty and enhance conservation in resource dependent communities, managers must identify existing livelihood strategies and the associated factors that impede household access to livelihood assets. Researchers increasingly advocate reallocating management power from exclusionary central institutions to a decentralized system of management based on local and inclusive participation. However, it is yet to be shown if decentralizing conservation leads to diversified livelihoods within a protected area. The purpose of this study was to identify and assess factors affecting household livelihood diversification within Nepal's Kanchenjunga Conservation Area Project, the first protected area in Asia to decentralize conservation. We randomly surveyed 25% of Kanchenjunga households to assess household socioeconomic and demographic characteristics and access to livelihood assets. We used a cluster analysis with the ten most common income generating activities (both on- and off-farm) to group the strategies households use to diversify livelihoods, and a multinomial logistic regression to identify predictors of livelihood diversification. We found four distinct groups of household livelihood strategies with a range of diversification that directly corresponded to household income. The predictors of livelihood diversification were more related to pre-existing socioeconomic and demographic factors (e.g., more landholdings and livestock, fewer dependents, receiving remittances) than activities sponsored by decentralizing conservation (e.g., microcredit, training, education, interaction with project staff). Taken together, our findings indicate that without direct policies to target marginalized groups, decentralized conservation in Kanchenjunga will continue to exclude marginalized groups, limiting a household's ability to diversify their livelihood and perpetuating their dependence on natural resources. Copyright © 2015 Elsevier Ltd. All rights reserved.

Decentralization and health resource allocation: a case study at the district level in Indonesia.

PubMed

Abdullah, Asnawi; Stoelwinder, Johannes

2008-01-01

Health resource allocation has been an issue of political debate in many health systems. However, the debate has tended to concentrate on vertical allocation from the national to regional level. Allocation within regions or institutions has been largely ignored. This study was conducted to contribute analysis to this gap. The objective was to investigate health resource allocation within District Health Offices (DHOs) and to compare the trends and patterns of several budget categories before and after decentralization. The study was conducted in three districts in the Province of Nanggroe Aceh Darussalam. Six fiscal year budgets, two before decentralization and four after, were studied. Data was collected from the Local Government Planning Office and DHOs. Results indicated that in the first year of implementing a decentralization policy, the local government budget rose sharply, particularly in the wealthiest district. In contrast, in relatively poor districts the budget was only boosted slightly. Increasing total local government budgets had a positive impact on increasing the health budget. The absolute amount of health budgets increased significantly, but by percentage did not change very much. Budgets for several projects and budget items increased significantly, but others, such as health promotion, monitoring and evaluation, and public-goods-related activities, decreased. This study concluded that decentralization in Indonesia had made a positive impact on district government fiscal capacity and had affected DHO budgets positively. However, an imbalanced budget allocation between projects and budget items was obvious, and this needs serious attention from policy makers. Otherwise, decentralization will not significantly improve the health system in Indonesia.

Expansion of a residency program through provision of second-shift decentralized services.

PubMed

Host, Brian D; Anderson, Michael J; Lucas, Paul D

2014-12-15

The rationale for and logistics of the expansion of a postgraduate year 1 (PGY1) residency program in a community hospital are described. Baptist Health Lexington, a nonprofit community hospital in Lexington, Kentucky, sought to expand the PGY1 program by having residents perform second-shift decentralized pharmacist functions. Program expansion was predicated on aligning resident staffing functions with current hospitalwide initiatives involving medication reconciliation and patient education. The focus was to integrate residents into the workflow while allowing them more time to practice as pharmacists and contribute to departmental objectives. The staffing function would increase residents' overall knowledge of departmental operations and foster their sense of independence and ownership. The decentralized functions would include initiation of clinical pharmacokinetic consultations, admission medication reconciliation, discharge teaching for patients with heart failure, and order-entry support from decentralized locations. The program grew from three to five residents and established a staffing rotation for second-shift decentralized coverage. The increased time spent staffing did not detract from the time allotted to previously established learning experiences and enhanced overall continuity of the staffing experience. The change also emphasized to the residents the importance of integration of distributive and clinical functions within the department. Pharmacist participation in admission and discharge medication reconciliation activities has also increased patient satisfaction, evidenced by follow-up surveys conducted by the hospital. A PGY1 residency program was expanded through the provision of second-shift decentralized clinical services, which helped provide residents with increased patient exposure and enhanced staffing experience. Copyright © 2014 by the American Society of Health-System Pharmacists, Inc. All rights reserved.

Using Systems Theory to Examine Patient and Nurse Structures, Processes, and Outcomes in Centralized and Decentralized Units.

PubMed

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

2018-01-01

This study utilizes systems theory to understand how changes to physical design structures impact communication processes and patient and staff design-related outcomes. Many scholars and researchers have noted the importance of communication and teamwork for patient care quality. Few studies have examined changes to nursing station design within a systems theory framework. This study employed a multimethod, before-and-after, quasi-experimental research design. Nurses completed surveys in centralized units and later in decentralized units ( N = 26 pre , N = 51 post ). Patients completed surveys ( N = 62 pre ) in centralized units and later in decentralized units ( N = 49 post ). Surveys included quantitative measures and qualitative open-ended responses. Patients preferred the decentralized units because of larger single-occupancy rooms, greater privacy/confidentiality, and overall satisfaction with design. Nurses had a more complex response. Nurses approved the patient rooms, unit environment, and noise levels in decentralized units. However, they reported reduced access to support spaces, lower levels of team/mentoring communication, and less satisfaction with design than in centralized units. Qualitative findings supported these results. Nurses were more positive about centralized units and patients were more positive toward decentralized units. The results of this study suggest a need to understand how system components operate in concert. A major contribution of this study is the inclusion of patient satisfaction with design, an important yet overlooked fact in patient satisfaction. Healthcare design researchers and practitioners may consider how changing system interdependencies can lead to unexpected changes to communication processes and system outcomes in complex systems.

The Rhetoric of Decentralization

ERIC Educational Resources Information Center

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…

PARTICIPATORY STORM WATER MANAGEMENT AND SUSTAINABILITY – WHAT ARE THE CONNECTIONS?

EPA Science Inventory

Urban stormwater is typically conveyed to centralized infrastructure, and there is great potential for reducing stormwater runoff quantity through decentralization. For areas which are already developed, decentralization of stormwater management involves private property and poss...

Improving antiretroviral therapy scale-up and effectiveness through service integration and decentralization.

PubMed

Suthar, Amitabh B; Rutherford, George W; Horvath, Tara; Doherty, Meg C; Negussie, Eyerusalem K

2014-03-01

Current service delivery systems do not reach all people in need of antiretroviral therapy (ART). In order to inform the operational and service delivery section of the WHO 2013 consolidated antiretroviral guidelines, our objective was to summarize systematic reviews on integrating ART delivery into maternal, newborn, and child health (MNCH) care settings in countries with generalized epidemics, tuberculosis (TB) treatment settings in which the burden of HIV and TB is high, and settings providing opiate substitution therapy (OST); and decentralizing ART into primary health facilities and communities. A summary of systematic reviews. The reviewers searched PubMed, Embase, PsycINFO, Web of Science, CENTRAL, and the WHO Index Medicus databases. Randomized controlled trials and observational cohort studies were included if they compared ART coverage, retention in HIV care, and/or mortality in MNCH, TB, or OST facilities providing ART with MNCH, TB, or OST facilities providing ART services separately; or primary health facilities or communities providing ART with hospitals providing ART. The reviewers identified 28 studies on integration and decentralization. Antiretroviral therapy integration into MNCH facilities improved ART coverage (relative risk [RR] 1.37, 95% confidence interval [CI] 1.05-1.79) and led to comparable retention in care. ART integration into TB treatment settings improved ART coverage (RR 1.83, 95% CI 1.48-2.23) and led to a nonsignificant reduction in mortality (RR 0.55, 95% CI 0.29-1.05). The limited data on ART integration into OST services indicated comparable rates of ART coverage, retention, and mortality. Partial decentralization into primary health facilities improved retention (RR 1.05, 95% CI 1.01-1.09) and reduced mortality (RR 0.34, 95% CI 0.13-0.87). Full decentralization improved retention (RR 1.12, 95% CI 1.08-1.17) and led to comparable mortality. Community-based ART led to comparable rates of retention and mortality. Integrating ART into MNCH, TB, and OST services was often associated with improvements in ART coverage, and decentralization of ART into primary health facilities and communities was often associated with improved retention. Neither integration nor decentralization was associated with adverse outcomes. These data contributed to recommendations in the WHO 2013 consolidated antiretroviral guidelines to integrate ART delivery into MNCH, TB, and OST services and to decentralize ART.

Modeling and Optimization of Recycled Water Systems to Augment Urban Groundwater Recharge through Underutilized Stormwater Spreading Basins.

PubMed

Bradshaw, Jonathan L; Luthy, Richard G

2017-10-17

Infrastructure systems that use stormwater and recycled water to augment groundwater recharge through spreading basins represent cost-effective opportunities to diversify urban water supplies. However, technical questions remain about how these types of managed aquifer recharge systems should be designed; furthermore, existing planning tools are insufficient for performing robust design comparisons. Addressing this need, we present a model for identifying the best-case design and operation schedule for systems that deliver recycled water to underutilized stormwater spreading basins. Resulting systems are optimal with respect to life cycle costs and water deliveries. Through a case study of Los Angeles, California, we illustrate how delivering recycled water to spreading basins could be optimally implemented. Results illustrate trade-offs between centralized and decentralized configurations. For example, while a centralized Hyperion system could deliver more recycled water to the Hansen Spreading Grounds, this system incurs approximately twice the conveyance cost of a decentralized Tillman system (mean of 44% vs 22% of unit life cycle costs). Compared to existing methods, our model allows for more comprehensive and precise analyses of cost, water volume, and energy trade-offs among different design scenarios. This model can inform decisions about spreading basin operation policies and the development of new water supplies.

Orchestrating French Music Conservatories: European Political Interventions and Local Governance

ERIC Educational Resources Information Center

Raevskikh, Elena

2017-01-01

Supported by the omnipresent State in the past, French music education leans increasingly towards a more liberal and competitive model. In the current context of a decentralized economy and European integration, music conservatories are called upon to contribute to regional and municipal development and enhance European student mobility. How do…

Mission Command and the Starfish Organizational Models: A Comparison of Organizational Philosophies in a Decentralized Combat Environment

DTIC Science & Technology

2015-06-12

market. However, in 2004, Netflix changed the home video entertainment landscape from brick and mortar rental outlets to the DVD-by-mail business...competing companies had very different organizational structures and leadership styles. Amazon stayed true to an online brick and mortar platform

School Openness, Parent Participation and Satisfaction: An Exploration of Causal Models.

ERIC Educational Resources Information Center

Spivak, Harriet

This case study in policy research was prompted by: (1) concern about a methodological issue: how useful are cross-sectional, non-experimental data for answering policy questions?--and, (2) interest in some policy issues raised by the school decentralization/community control controversies and participatory reforms of the 1960s--are participatory…

Review of "The Louisiana Recovery School District: Lessons for the Buckeye State"

ERIC Educational Resources Information Center

Buras, Kristen L.

2012-01-01

In "The Louisiana Recovery School District: Lessons for the Buckeye State," the Thomas B. Fordham Institute criticizes local urban governance structures and presents the decentralized, charter-school-driven Recovery School District (RSD) in New Orleans as a successful model for fiscal and academic performance. Absent from the review is…

Decentralized Control of a Large Space Structure as Applied to the CSDL 2 Model.

DTIC Science & Technology

1982-12-01

and are arranged by their respective controller assignments. The individual modes may be identified by the imaginary parts of the eigen- values, as...August 1958 to Phillip Z. and Hanako Y. Aldridge in Johnson Air Force Base, Japan. After a childhood in the United States, he returned to Japan

Evaluation and Decentralised Governance: Examples of Inspections in Polycentric Education Systems

ERIC Educational Resources Information Center

Ehren, M. C. M.; Janssens, F. J. G.; Brown, M.; McNamara, G.; O'Hara, J.; Shevlin, P.

2017-01-01

Across Europe schools and other service providers increasingly operate in networks to provide inclusive education or develop and implement more localized school-to-school improvement models. As some education systems move towards more decentralized decision-making where multiple actors have an active role in steering and governing schools, the…

Conditions for Distance Education at the University Level in Sweden and the Other Nordic Countries.

ERIC Educational Resources Information Center

Willen, Birgitta

This report discusses the highly decentralized Nordic model of distance education at the university level, which involves giving responsibility for carrying out distance education to the individual university departments. Meeting at the university and using the telephone are primary contact methods. The report includes a discussion of higher…

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

PubMed

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.

Coupled economic-coastline modeling with suckers and free riders

NASA Astrophysics Data System (ADS)

Williams, Zachary C.; McNamara, Dylan E.; Smith, Martin D.; Murray, A. Brad.; Gopalakrishnan, Sathya

2013-06-01

erosion is a natural trend along most sandy coastlines. Humans often respond to shoreline erosion with beach nourishment to maintain coastal property values. Locally extending the shoreline through nourishment alters alongshore sediment transport and changes shoreline dynamics in adjacent coastal regions. If left unmanaged, sandy coastlines can have spatially complex or simple patterns of erosion due to the relationship of large-scale morphology and the local wave climate. Using a numerical model that simulates spatially decentralized and locally optimal nourishment decisions characteristic of much of U.S. East Coast beach management, we find that human erosion intervention does not simply reflect the alongshore erosion pattern. Spatial interactions generate feedbacks in economic and physical variables that lead to widespread emergence of "free riders" and "suckers" with subsequent inequality in the alongshore distribution of property value. Along cuspate coastlines, such as those found along the U.S. Southeast Coast, these long-term property value differences span an order of magnitude. Results imply that spatially decentralized management of nourishment can lead to property values that are divorced from spatial erosion signals; this management approach is unlikely to be optimal.

Designing multifocal corneal models to correct presbyopia by laser ablation

NASA Astrophysics Data System (ADS)

Alarcón, Aixa; Anera, Rosario G.; Del Barco, Luis Jiménez; Jiménez, José R.

2012-01-01

Two multifocal corneal models and an aspheric model designed to correct presbyopia by corneal photoablation were evaluated. The design of each model was optimized to achieve the best visual quality possible for both near and distance vision. In addition, we evaluated the effect of myosis and pupil decentration on visual quality. The corrected model with the central zone for near vision provides better results since it requires less ablated corneal surface area, permits higher addition values, presents stabler visual quality with pupil-size variations and lower high-order aberrations.

Engaging Social Capital for Decentralized Urban Stormwater Management (Paper in Non-EPA Proceedings)

EPA Science Inventory

Decentralized approaches to urban stormwater management, whereby installations of green infrastructure (e.g., rain gardens, bioswales, constructed wetlands) are dispersed throughout a management area, are cost-effective solutions with co-benefits beyond just water abatement. Inst...

Decentralized Modular Systems Versus Centralized Systems.

ERIC Educational Resources Information Center

Crossey, R. E.

Building design, planning, and construction programing for modular decentralized mechanical building systems are outlined in terms of costs, performance, expansion and flexibility. Design strategy, approach, and guidelines for implementing such systems for buildings are suggested, with emphasis on mechanical equipment and building element…

Educational Decentralization Policies in Argentina and Brazil: Exploring the New Trends.

ERIC Educational Resources Information Center

Derqui, Jorge M. Gorostiaga

2001-01-01

Analyzes educational decentralization trends and policies in Argentina and Brazil during 1990s, includes case studies. Discusses historical background and rationales behind "provinicialization" in Argentina and "municipalization" in Brazil; identifies commonalities, including centralization of curriculum and evaluation…

Satellite Power System (SPS) centralization/decentralization

NASA Technical Reports Server (NTRS)

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.

Decentralized control

NASA Technical Reports Server (NTRS)

Steffen, Chris

1990-01-01

An overview of the time-delay problem and the reliability problem which arise in trying to perform robotic construction operations at a remote space location are presented. The effects of the time-delay upon the control system design will be itemized. A high level overview of a decentralized method of control which is expected to perform better than the centralized approach in solving the time-delay problem is given. The lower level, decentralized, autonomous, Troter Move-Bar algorithm is also presented (Troters are coordinated independent robots). The solution of the reliability problem is connected to adding redundancy to the system. One method of adding redundancy is given.

Decentralized water resources management in Mozambique: Challenges of implementation at the river basin level

NASA Astrophysics Data System (ADS)

Inguane, Ronaldo; Gallego-Ayala, Jordi; Juízo, Dinis

In the context of integrated water resources management implementation, the decentralization of water resources management (DWRM) at the river basin level is a crucial aspect for its success. However, decentralization requires the creation of new institutions on the ground, to stimulate an environment enabling stakeholder participation and integration into the water management decision-making process. In 1991, Mozambique began restructuring its water sector toward operational decentralized water resources management. Within this context of decentralization, new legal and institutional frameworks have been created, e.g., Regional Water Administrations (RWAs) and River Basin Committees. This paper identifies and analyzes the key institutional challenges and opportunities of DWRM implementation in Mozambique. The paper uses a critical social science research methodology for in-depth analysis of the roots of the constraining factors for the implementation of DWRM. The results obtained suggest that RWAs should be designed considering the specific geographic and infrastructural conditions of their jurisdictional areas and that priorities should be selected in their institutional capacity building strategies that match local realities. Furthermore, the results also indicate that RWAs have enjoyed limited support from basin stakeholders, mainly in basins with less hydraulic infrastructure, in securing water availability for their users and minimizing the effect of climate variability.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jeong, Hyunju; Pandit, Arka; Crittenden, John

The population growth coupled with increasing urbanization is predicted to exert a huge demand on the growth and retrofit of urban infrastructure, particularly in water and energy systems. The U.S. population is estimated to grow by 23% (UN, 2009) between 2005 and 2030. The corresponding increases in energy and water demand were predicted as 14% (EIA, 2009) and 20% (Elcock, 2008), respectively. The water-energy nexus needs to be better understood to satisfy the increased demand in a sustainable manner without conflicting with environmental and economic constraints. Overall, 4% of U.S. power generation is used for water distribution (80%) and treatmentmore » (20%). 3% of U.S. water consumption (100 billion gallons per day, or 100 BGD) and 40% of U.S. water withdrawal (340 BGD) are for thermoelectric power generation (Goldstein and Smith, 2002). The water demand for energy production is predicted to increase most significantly among the water consumption sectors by 2030. On the other hand, due to the dearth of conventional water sources, energy intensive technologies are increasingly in use to treat seawater and brackish groundwater for water supply. Thus comprehending the interrelation and interdependency between water and energy system is imperative to evaluate sustainable water and energy supply alternatives for cities. In addition to the water-energy nexus, decentralized or distributed concept is also beneficial for designing sustainable water and energy infrastructure as these alternatives require lesser distribution lines and space in a compact urban area. Especially, the distributed energy infrastructure is more suited to interconnect various large and small scale renewable energy producers which can be expected to mitigate greenhouse gas (GHG) emissions. In the case of decentralized water infrastructure, on-site wastewater treatment facility can provide multiple benefits. Firstly, it reduces the potable water demand by reusing the treated water for non-potable uses and secondly, it also reduces the wastewater load to central facility. In addition, lesser dependency on the distribution network contributes to increased reliability and resiliency of the infrastructure. The goal of this research is to develop a framework which seeks an optimal combination of decentralized water and energy alternatives and centralized infrastructures based on physical and socio-economic environments of a region. Centralized and decentralized options related to water, wastewater and stormwater and distributed energy alternatives including photovoltaic (PV) generators, fuel cells and microturbines are investigated. In the context of the water-energy nexus, water recovery from energy alternatives and energy recovery from water alternatives are reflected. Alternatives recapturing nutrients from wastewater are also considered to conserve depleting resources. The alternatives are evaluated in terms of their life-cycle environmental impact and economic performance using a hybrid life cycle assessment (LCA) tool and cost benefit analysis, respectively. Meeting the increasing demand of a test bed, an optimal combination of the alternatives is designed to minimize environmental and economic impacts including CO2 emissions, human health risk, natural resource use, and construction and operation cost. The framework determines the optimal combination depending on urban density, transmission or conveyance distance or network, geology, climate, etc. Therefore, it will be also able to evaluate infrastructure resiliency against physical and socio-economic challenges such as population growth, severe weather, energy and water shortage, economic crisis, and so on.« less

Decentralized control algorithms of a group of vehicles in 2D space

NASA Astrophysics Data System (ADS)

Pshikhopov, V. K.; Medvedev, M. Y.; Fedorenko, R. V.; Gurenko, B. V.

2017-02-01

The problem of decentralized control of group of robots, described by kinematic and dynamic equations of motion in the plane, is considered. Group performs predetermined rectangular area passing at a fixed speed, keeping the line and a uniform distribution. The environment may contain a priori unknown moving or stationary obstacles. Decentralized control algorithms, based on the formation of repellers in the state space of robots, are proposed. These repellers form repulsive forces generated by dynamic subsystems that extend the state space of robots. These repulsive forces are dynamic functions of distances and velocities of robots in the area of operation of the group. The process of formation of repellers allows to take into account the dynamic properties of robots, such as the maximum speed and acceleration. The robots local control law formulas are derived based on positionally-trajectory control method, which allows to operate with non-linear models. Lyapunov function in the form of a quadratic function of the state variables is constructed to obtain a nonlinear closed-loop control system. Due to the fact that a closed system is decomposed into two independent subsystems Lyapunov function is also constructed as two independent functions. Numerical simulation of the motion of a group of five robots is presented. In this simulation obstacles are presented by the boundaries of working area and a movable object of a given radius, moving rectilinear and uniform. Obstacle speed is comparable to the speeds of the robots in a group. The advantage of the proposed method is ensuring the stability of the trajectories and consideration of the limitations on the speed and acceleration at the trajectory planning stage. Proposed approach can be used for more general robots' models, including robots in the three-dimensional environment.

Schisms in the church: National Health Service systems and institutional divergence in England and Wales.

PubMed

Hughes, David; Vincent-Jones, Peter

2008-12-01

Since devolution, the four countries of the United Kingdom have pursued strikingly different National Health Service (NHS) reforms. While England created a supply-side market more radical than the previous internal market system, Wales moved to a softer version of the purchaser/provider split emphasizing localism. This article deploys institutional theory to analyze the forces shaping change, and describes the hybrid forms of economic organization emerging, including the economic regulation model implemented in England. The schism that has resulted in separate NHS subsystems warrants a different analysis from the more familiar phenomenon of infield divergence. We argue that schism was triggered by political-regulatory influences rather than economic or other social institutional forces, and predict that other decentralized public health care systems may follow a similar path. While political-regulatory, normative, and cognitive institutional influences push in the same direction in Wales, the misalignment of political-regulatory and normative elements in England looks set to result in a period of organizational turbulence.

[Ongoing, flexible distance learning through the Internet: course on decentralized management of human resources in health care].

PubMed

Struchiner, Miriam; Roschke, Maria Alice; Ricciardi, Regina Maria Vieira

2002-03-01

This paper describes the Course on Decentralized Management of Human Resources in Health Care, which is an Internet-based distance learning program to train and provide continuing education for health care professionals. The program is an initiative of the Pan American Health Organization, and it was organized in response to the growing need for self-reliant professionals who can constantly upgrade their knowledge without having to leave their place of work. The proposed model promotes an educational process that brings together theory and practice in realistic and relevant contexts and that maximizes the participation of students, both individually and in groups. The program has been evaluated in pilot studies in Brazil, Chile, and Peru. Following these assessments, the course has been adapted to facilitate its implementation and to adjust its contents to fit each country's circumstances.

Decentralized Observer with a Consensus Filter for Distributed Discrete-Time Linear Systems

NASA Technical Reports Server (NTRS)

Acikmese, Behcet; Mandic, Milan

2011-01-01

This paper presents a decentralized observer with a consensus filter for the state observation of a discrete-time linear distributed systems. In this setup, each agent in the distributed system has an observer with a model of the plant that utilizes the set of locally available measurements, which may not make the full plant state detectable. This lack of detectability is overcome by utilizing a consensus filter that blends the state estimate of each agent with its neighbors' estimates. We assume that the communication graph is connected for all times as well as the sensing graph. It is proven that the state estimates of the proposed observer asymptotically converge to the actual plant states under arbitrarily changing, but connected, communication and sensing topologies. As a byproduct of this research, we also obtained a result on the location of eigenvalues, the spectrum, of the Laplacian for a family of graphs with self-loops.

[Administrative efficiency in the Mexican Fund for the Prevention of Catastrophic Expenditures in Health].

PubMed

Orozco-Núñez, Emanuel; Alcalde-Rabanal, Jaqueline; Navarro, Juan; Lozano, Rafael

2016-01-01

To show that the administrative regime of specialized hospitals has some influence on the administrative processes to operate the Mexican Fund for Catastrophic Expenditures in Health (FPGC, in Spanish), for providing health care to breast cancer, cervical cancer and child leukemia. The variable for estimating administrative efficiency was the time estimated from case notification to reimbursement. For its estimation, semistructured interviews were applied to key actors involved in management of cancer care financed by FPGC. Additionally, a group of experts was organized to make recommendations for improving processes. Specialized hospitals with a decentralized scheme showed less time to solve the administrative process in comparison with the model on the hospitals dependent on State Health Services, where timing and intermediation levels were higher. Decentralized hospitals administrative scheme for specialized care is more efficient, because they tend to be more autonomous.

Decentralized Grid Scheduling with Evolutionary Fuzzy Systems

NASA Astrophysics Data System (ADS)

Fölling, Alexander; Grimme, Christian; Lepping, Joachim; Papaspyrou, Alexander

In this paper, we address the problem of finding workload exchange policies for decentralized Computational Grids using an Evolutionary Fuzzy System. To this end, we establish a non-invasive collaboration model on the Grid layer which requires minimal information about the participating High Performance and High Throughput Computing (HPC/HTC) centers and which leaves the local resource managers completely untouched. In this environment of fully autonomous sites, independent users are assumed to submit their jobs to the Grid middleware layer of their local site, which in turn decides on the delegation and execution either on the local system or on remote sites in a situation-dependent, adaptive way. We find for different scenarios that the exchange policies show good performance characteristics not only with respect to traditional metrics such as average weighted response time and utilization, but also in terms of robustness and stability in changing environments.

[Primary care: decentralization and efficiency].

PubMed

Pinillos, M; Antoñanzas, F

2002-01-01

The purpose of this study was to evaluate whether the productive behavior of health centers in autonomous communities with competence in health is more efficient than that among centers belonging to Spanish public health system (INSALUD). The technical efficiency of 66 health centers in Alava, Navarre and La Rioja was analyzed. Centers in autonomous communities that in 1997 had been granted complete authority from the central government to manage their healthcare services were compared with centers whose administration, in the same year, was still in the hands of INSALUD. The method used to measure and quantify the efficiency of these centers was data envelopment analysis. Nonparametric contrast of the health centers' mean efficiency rates revealed no significant differences in the (in)efficiency of centers from La Rioja, Navarre and Alava. The results obtained from the model of efficiency measurement used did not indicate that decentralization improves the productive efficiency of primary care centers.

Decentralization and centralization of healthcare resources: investigating the associations of hospital competition and number of cardiologists per hospital with mortality and resource utilization in Japan.

PubMed

Park, Sungchul; Lee, Jason; Ikai, Hiroshi; Otsubo, Tetsuya; Imanaka, Yuichi

2013-11-01

To investigate the associations of hospital competition and number of cardiologists per hospital (indicating the decentralization and centralization of healthcare resources, respectively) with 30-day in-hospital mortality, healthcare spending, and length of stay (LOS) among patients with acute myocardial infarction (AMI) in Japan. We collected data from 23,197 AMI patients admitted to 172 hospitals between 2008 and 2011. Hospital competition and number of cardiologists per hospital were analyzed as exposure variables in multilevel regression models for in-hospital mortality, healthcare spending, and LOS. Other covariates included patient, hospital, and regional variables; as well as the use of percutaneous coronary intervention (PCI). Hospitals in competitive regions and hospitals with a higher number of cardiologists were both associated lower in-hospital mortality. Additionally, hospitals in competition regions were also associated with longer LOS durations, whereas hospitals with more cardiologists had higher spending. The use of PCI was also associated with reduced mortality, increased spending and increased LOS. Centralization of cardiologists at the hospital level and decentralization of acute hospitals at the regional level may be contributing factors for improving the quality of care in Japan. Policymakers need to strike a balance between these two approaches to improve healthcare provision and quality. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Life Cycle Assessment and Cost Analysis of Water and ...

EPA Pesticide Factsheets

changes in drinking and wastewater infrastructure need to incorporate a holistic view of the water service sustainability tradeoffs and potential benefits when considering shifts towards new treatment technology, decentralized systems, energy recovery and reuse of treated wastewater. The main goal of this study is to determine the influence of scale on the energy and cost performance of different transitional membrane bioreactors (MBR) in decentralized wastewater treatment (WWT) systems by performing a life cycle assessment (LCA) and cost analysis. LCA is a tool used to quantify sustainability-related metrics from a systems perspective. The study calculates the environmental and cost profiles of both aerobic MBRs (AeMBR) and anaerobic MBRs (AnMBR), which not only recover energy from waste, but also produce recycled water that can displace potable water for uses such as irrigation and toilet flushing. MBRs represent an intriguing technology to provide decentralized WWT services while maximizing resource recovery. A number of scenarios for these WWT technologies are investigated for different scale systems serving various population density and land area combinations to explore the ideal application potentials. MBR systems are examined from 0.05 million gallons per day (MGD) to 10 MGD and serve land use types from high density urban (100,000 people per square mile) to semi-rural single family (2,000 people per square mile). The LCA and cost model was built with ex

Noise, cost and speed-accuracy trade-offs: decision-making in a decentralized system

PubMed Central

Marshall, James A.R.; Dornhaus, Anna; Franks, Nigel R.; Kovacs, Tim

2005-01-01

Many natural and artificial decision-making systems face decision problems where there is an inherent compromise between two or more objectives. One such common compromise is between the speed and accuracy of a decision. The ability to exploit the characteristics of a decision problem in order to vary between the extremes of making maximally rapid, or maximally accurate decisions, is a useful property of such systems. Colonies of the ant Temnothorax albipennis (formerly Leptothorax albipennis) are a paradigmatic decentralized decision-making system, and have been shown flexibly to compromise accuracy for speed when making decisions during house-hunting. During emigration, a colony must typically evaluate and choose between several possible alternative new nest sites of differing quality. In this paper, we examine this speed-accuracy trade-off through modelling, and conclude that noise and time-cost of assessing alternative choices are likely to be significant for T. albipennis. Noise and cost of such assessments are likely to mean that T. albipennis' decision-making mechanism is Pareto-optimal in one crucial regard; increasing the willingness of individuals to change their decisions cannot improve collective accuracy overall without impairing speed. We propose that a decentralized control algorithm based on this emigration behaviour may be derived for applications in engineering domains and specify the characteristics of the problems to which it should be suited, based on our new results. PMID:16849234

Final Report for Bio-Inspired Approaches to Moving-Target Defense Strategies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fink, Glenn A.; Oehmen, Christopher S.

This report records the work and contributions of the NITRD-funded Bio-Inspired Approaches to Moving-Target Defense Strategies project performed by Pacific Northwest National Laboratory under the technical guidance of the National Security Agency’s R6 division. The project has incorporated a number of bio-inspired cyber defensive technologies within an elastic framework provided by the Digital Ants. This project has created the first scalable, real-world prototype of the Digital Ants Framework (DAF)[11] and integrated five technologies into this flexible, decentralized framework: (1) Ant-Based Cyber Defense (ABCD), (2) Behavioral Indicators, (3) Bioinformatic Clas- sification, (4) Moving-Target Reconfiguration, and (5) Ambient Collaboration. The DAF canmore » be used operationally to decentralize many such data intensive applications that normally rely on collection of large amounts of data in a central repository. In this work, we have shown how these component applications may be decentralized and may perform analysis at the edge. Operationally, this will enable analytics to scale far beyond current limitations while not suffering from the bandwidth or computational limitations of centralized analysis. This effort has advanced the R6 Cyber Security research program to secure digital infrastructures by developing a dynamic means to adaptively defend complex cyber systems. We hope that this work will benefit both our client’s efforts in system behavior modeling and cyber security to the overall benefit of the nation.« less

Adult Education in Modern Greece.

ERIC Educational Resources Information Center

Boucouvalas, Marcie

1982-01-01

Greece's adult education enterprise is well-organized, well-thought-out, and well-grounded. A sound philosophical, theoretical, and conceptual foundation supports its operational components. A unique feature is its blend of centralization and decentralization: centralized policy and guidance and decentralized decision making and autonomy over…

The Organization of Correctional Education Services

ERIC Educational Resources Information Center

Gehring, Thom

2007-01-01

There have been five major types of correctional education organizations over the centuries: Sabbath school, traditional or decentralized, bureau, correctional school district (CSD), and integral education. The middle three are modern organizational patterns that can be implemented throughout a system: Decentralized, bureau, and CSD. The…

Regionalism, Devolution and Education

ERIC Educational Resources Information Center

Bogdanor, Vernon

1977-01-01

Described are effects of political decentralization in the United Kingdom on political and social institutions, particularly education. The author concludes that regionalism could yield advantages of power decentralization, diversity of decision making, and educational systems which are more closely connected to regional and local traditions.…

Swarm Intelligence for Urban Dynamics Modelling

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ghnemat, Rawan; Bertelle, Cyrille; Duchamp, Gerard H. E.

2009-04-16

In this paper, we propose swarm intelligence algorithms to deal with dynamical and spatial organization emergence. The goal is to model and simulate the developement of spatial centers using multi-criteria. We combine a decentralized approach based on emergent clustering mixed with spatial constraints or attractions. We propose an extension of the ant nest building algorithm with multi-center and adaptive process. Typically, this model is suitable to analyse and simulate urban dynamics like gentrification or the dynamics of the cultural equipment in urban area.

Swarm Intelligence for Urban Dynamics Modelling

NASA Astrophysics Data System (ADS)

Ghnemat, Rawan; Bertelle, Cyrille; Duchamp, Gérard H. E.

2009-04-01

In this paper, we propose swarm intelligence algorithms to deal with dynamical and spatial organization emergence. The goal is to model and simulate the developement of spatial centers using multi-criteria. We combine a decentralized approach based on emergent clustering mixed with spatial constraints or attractions. We propose an extension of the ant nest building algorithm with multi-center and adaptive process. Typically, this model is suitable to analyse and simulate urban dynamics like gentrification or the dynamics of the cultural equipment in urban area.

Turning Towards or Turning Away: A Comparison of Mindfulness Meditation and Guided Imagery Relaxation in Patients with Acute Depression.

PubMed

Costa, Ana; Barnhofer, Thorsten

2016-07-01

Disengaging from maladaptive thinking is an important imperative in the treatment of depression. Mindfulness training is aimed at helping patients acquire relevant skills for this purpose. It remains unclear, however, whether this practice is helpful when patients are acutely depressed. In order to investigate effects of mindfulness on symptoms and self-regulatory capacities in this group, the current study compared a brief training in mindfulness (n = 19) to guided imagery relaxation (n = 18). Participants were introduced to the respective techniques in a single session, and practised daily over one week. Self-reported severity of symptoms, difficulties in emotion-regulation, attentional control, the ability to decentre, and mindfulness were assessed pre and postintervention, and at a one-week follow-up. Symptoms of depression significantly decreased and self-regulatory functioning significantly increased in both groups, with changes being maintained during follow-up. When controlling for change in depressive symptoms, results showed significantly higher improvements in emotion regulation at follow-up in the mindfulness group. The ability to decentre predicted changes in symptoms from pre to postintervention, while mindfulness skills predicted changes in symptoms during the maintenance phase. The findings suggest that both practices can help to instigate reductions in symptoms and enhance self-regulatory functioning in depression. However, in order to improve emotion regulation above levels explained by reductions in symptoms more intentional mental training seems necessary. Furthermore, while the ability to disengage from negative patterns of thinking seems crucial for initial reduction of symptoms, maintenance of gains might require broader skills in mindfulness.

Decentralization in Zambia: resource allocation and district performance.

PubMed

Bossert, Thomas; Chitah, Mukosha Bona; Bowser, Diana

2003-12-01

Zambia implemented an ambitious process of health sector decentralization in the mid 1990s. This article presents an assessment of the degree of decentralization, called 'decision space', that was allowed to districts in Zambia, and an analysis of data on districts available at the national level to assess allocation choices made by local authorities and some indicators of the performance of the health systems under decentralization. The Zambian officials in health districts had a moderate range of choice over expenditures, user fees, contracting, targeting and governance. Their choices were quite limited over salaries and allowances and they did not have control over additional major sources of revenue, like local taxes. The study found that the formula for allocation of government funding which was based on population size and hospital beds resulted in relatively equal per capita expenditures among districts. Decentralization allowed the districts to make decisions on internal allocation of resources and on user fee levels and expenditures. General guidelines for the allocation of resources established a maximum and minimum percentage to be allocated to district offices, hospitals, health centres and communities. Districts tended to exceed the maximum for district offices, but the large urban districts and those without public district hospitals were not even reaching the minimum for hospital allocations. Wealthier and urban districts were more successful in raising revenue through user fees, although the proportion of total expenditures that came from user fees was low. An analysis of available indicators of performance, such as the utilization of health services, immunization coverage and family planning activities, found little variation during the period 1995-98 except for a decline in immunization coverage, which may have also been affected by changes in donor funding. These findings suggest that decentralization may not have had either a positive or negative impact on services.

Development of a pharmacy resident rotation to expand decentralized clinical pharmacy services.

PubMed

Hill, John D; Williams, Jonathan P; Barnes, Julie F; Greenlee, Katie M; Cardiology, Bcps-Aq; Leonard, Mandy C

2017-07-15

The development of a pharmacy resident rotation to expand decentralized clinical pharmacy services is described. In an effort to align with the initiatives proposed within the ASHP Practice Advancement Initiative, the department of pharmacy at Cleveland Clinic, a 1,400-bed academic, tertiary acute care medical center in Cleveland, Ohio, established a goal to provide decentralized clinical pharmacy services for 100% of patient care units within the hospital. Patient care units that previously had no decentralized pharmacy services were evaluated to identify opportunities for expansion. Metrics analyzed included number of medication orders verified per hour, number of pharmacy dosing consultations, and number of patient discharge counseling sessions. A pilot study was conducted to assess the feasibility of this service and potential resident learning opportunities. A learning experience description was drafted, and feedback was solicited regarding the development of educational components utilized throughout the rotation. Pharmacists who were providing services to similar patient populations were identified to serve as preceptors. Staff pharmacists were deployed to previously uncovered patient care units, with pharmacy residents providing decentralized services on previously covered areas. A rotating preceptor schedule was developed based on geographic proximity and clinical expertise. An initial postimplementation assessment of this resident-driven service revealed that pharmacy residents provided a comparable level of pharmacy services to that of staff pharmacists. Feedback collected from nurses, physicians, and pharmacy staff also supported residents' ability to operate sufficiently in this role to optimize patient care. A learning experience developed for pharmacy residents in a large medical center enabled the expansion of decentralized clinical services without requiring additional pharmacist full-time equivalents. Copyright © 2017 by the American Society of Health-System Pharmacists, Inc. All rights reserved.

[Clinical results of the aspheric intraocular lens FY-60AD (Hoya) with particular respect to decentration and tilt].

PubMed

Mester, U; Heinen, S; Kaymak, H

2010-09-01

Aspheric intraocular lenses (IOLs) aim to improve visual function and particularly contrast vision by neutralizing spherical aberration. One drawback of such IOLs is the enhanced sensitivity to decentration and tilt, which can deteriorate image quality. A total of 30 patients who received bilateral phacoemulsification before implantation of the aspheric lens FY-60AD (Hoya) were included in a prospective study. In 25 of the patients (50 eyes) the following parameters could be assessed 3 months after surgery: visual acuity, refraction, contrast sensitivity, pupil size, wavefront errors and decentration and tilt using a newly developed device. The functional results were very satisfying and comparable to results gained with other aspheric IOLs. The mean refraction was sph + 0.1 D (±0.7 D) and cyl 0.6 D (±0.8 D). The spherical equivalent was −0.2 D (±0.6 D). Wavefront measurements revealed a good compensation of the corneal spherical aberration but vertical and horizontal coma also showed opposing values in the cornea and IOL. The assessment of the lens position using the Purkinje meter demonstrated uncritical amounts of decentration and tilt. The mean amount of decentration was 0.2 mm±0.2 mm in the horizontal and vertical directions. The mean amount of tilt was 4.0±2.1° in horizontal and 3.0±2.5° in vertical directions. In a normal dioptric power range the aspheric IOL FY-60AD compensates the corneal spherical aberration very well with only minimal decentration. The slight tilt is symmetrical in both eyes and corresponds to the position of the crystalline lens in young eyes. This may contribute to our findings of compensated corneal coma.

77 FR 56625 - Privacy Act of 1974; Systems of Records

Federal Register 2010, 2011, 2012, 2013, 2014

2012-09-13

... Internet at http://www.regulations.gov as they are received without change, including any personal.... George G. Meade, MD 20755-6000. Decentralized segments: Defense Intelligence Agency (DIA) Headquarters... decentralized system locations, write to the National Security Agency/Central Security Service, Freedom of...

OPTIMIZATION OF DECENTRALIZED BMP CONTROLS IN URBAN AREAS

EPA Science Inventory

This paper will present an overview of a recently completed project for the US EPA entitled, Optimization of Urban Wet-weather Flow Control Systems. The focus of this effort is on techniques that are suitable for evaluating decentralized BMP controls. The four major components ...

OPTIMIZATION OF DECENTRALIZED BMP CONTROLS IN URBAN AREAS

EPA Science Inventory

This paper will present an overview of a recently completed project for the US EPA entitled Optimization of Urban Wet-weather Flow Control Systems. The focus of this effort is on techniques that are suitable for evaluating decentralized BMP controls. The four major components o...

Endogenous System Microbes as Treatment Process Indicators for Decentralized Non-potable Water Reuse

EPA Science Inventory

Monitoring the efficacy of treatment strategies to remove pathogens in decentralized systems remains a challenge. Evaluating log reduction targets by measuring pathogen levels is hampered by their sporadic and low occurrence rates. Fecal indicator bacteria are used in centraliz...

Strategic Alignment: Recruiting Students in a Highly Decentralized Environment

ERIC Educational Resources Information Center

Levin, Richard

2016-01-01

All enrollment managers face some level of challenge related to decentralized decision making and operations. Policies and practices can vary considerably by academic area, creating administrative complexity, restricting the scope and speed of institutional initiatives, and limiting potential efficiencies. Central attempts to standardize or…

Academic Freedom.

ERIC Educational Resources Information Center

Ouchi, William G.

2004-01-01

Argues that school systems are so centralized that they waste money on bureaucratic operations and lack the capacity to respond rapidly to changing circumstances. A study of nine school systems that vary dramatically in their degree of decentralization demonstrates that true decentralization yields benefits in both efficiency and performance. (MLF)

DQM: Decentralized Quadratically Approximated Alternating Direction Method of Multipliers

NASA Astrophysics Data System (ADS)

Mokhtari, Aryan; Shi, Wei; Ling, Qing; Ribeiro, Alejandro

2016-10-01

This paper considers decentralized consensus optimization problems where nodes of a network have access to different summands of a global objective function. Nodes cooperate to minimize the global objective by exchanging information with neighbors only. A decentralized version of the alternating directions method of multipliers (DADMM) is a common method for solving this category of problems. DADMM exhibits linear convergence rate to the optimal objective but its implementation requires solving a convex optimization problem at each iteration. This can be computationally costly and may result in large overall convergence times. The decentralized quadratically approximated ADMM algorithm (DQM), which minimizes a quadratic approximation of the objective function that DADMM minimizes at each iteration, is proposed here. The consequent reduction in computational time is shown to have minimal effect on convergence properties. Convergence still proceeds at a linear rate with a guaranteed constant that is asymptotically equivalent to the DADMM linear convergence rate constant. Numerical results demonstrate advantages of DQM relative to DADMM and other alternatives in a logistic regression problem.

Concept of an innovative water management system with decentralized water reclamation and cascading material-cycle for agricultural areas.

PubMed

Fujiwara, T

2012-01-01

Unlike in urban areas where intensive water reclamation systems are available, development of decentralized technologies and systems is required for water use to be sustainable in agricultural areas. To overcome various water quality issues in those areas, a research project entitled 'Development of an innovative water management system with decentralized water reclamation and cascading material-cycle for agricultural areas under the consideration of climate change' was launched in 2009. This paper introduces the concept of this research and provides detailed information on each of its research areas: (1) development of a diffuse agricultural pollution control technology using catch crops; (2) development of a decentralized differentiable treatment system for livestock and human excreta; and (3) development of a cascading material-cycle system for water pollution control and value-added production. The author also emphasizes that the innovative water management system for agricultural areas should incorporate a strategy for the voluntary collection of bio-resources.

On the decentralized control of large-scale systems. Ph.D. Thesis

NASA Technical Reports Server (NTRS)

Chong, C.

1973-01-01

The decentralized control of stochastic large scale systems was considered. Particular emphasis was given to control strategies which utilize decentralized information and can be computed in a decentralized manner. The deterministic constrained optimization problem is generalized to the stochastic case when each decision variable depends on different information and the constraint is only required to be satisfied on the average. For problems with a particular structure, a hierarchical decomposition is obtained. For the stochastic control of dynamic systems with different information sets, a new kind of optimality is proposed which exploits the coupled nature of the dynamic system. The subsystems are assumed to be uncoupled and then certain constraints are required to be satisfied, either in a off-line or on-line fashion. For off-line coordination, a hierarchical approach of solving the problem is obtained. The lower level problems are all uncoupled. For on-line coordination, distinction is made between open loop feedback optimal coordination and closed loop optimal coordination.

Decentralized DC Microgrid Monitoring and Optimization via Primary Control Perturbations

NASA Astrophysics Data System (ADS)

Angjelichinoski, Marko; Scaglione, Anna; Popovski, Petar; Stefanovic, Cedomir

2018-06-01

We treat the emerging power systems with direct current (DC) MicroGrids, characterized with high penetration of power electronic converters. We rely on the power electronics to propose a decentralized solution for autonomous learning of and adaptation to the operating conditions of the DC Mirogrids; the goal is to eliminate the need to rely on an external communication system for such purpose. The solution works within the primary droop control loops and uses only local bus voltage measurements. Each controller is able to estimate (i) the generation capacities of power sources, (ii) the load demands, and (iii) the conductances of the distribution lines. To define a well-conditioned estimation problem, we employ decentralized strategy where the primary droop controllers temporarily switch between operating points in a coordinated manner, following amplitude-modulated training sequences. We study the use of the estimator in a decentralized solution of the Optimal Economic Dispatch problem. The evaluations confirm the usefulness of the proposed solution for autonomous MicroGrid operation.

Decentralized stabilization for a class of continuous-time nonlinear interconnected systems using online learning optimal control approach.

PubMed

Liu, Derong; Wang, Ding; Li, Hongliang

2014-02-01

In this paper, using a neural-network-based online learning optimal control approach, a novel decentralized control strategy is developed to stabilize a class of continuous-time nonlinear interconnected large-scale systems. First, optimal controllers of the isolated subsystems are designed with cost functions reflecting the bounds of interconnections. Then, it is proven that the decentralized control strategy of the overall system can be established by adding appropriate feedback gains to the optimal control policies of the isolated subsystems. Next, an online policy iteration algorithm is presented to solve the Hamilton-Jacobi-Bellman equations related to the optimal control problem. Through constructing a set of critic neural networks, the cost functions can be obtained approximately, followed by the control policies. Furthermore, the dynamics of the estimation errors of the critic networks are verified to be uniformly and ultimately bounded. Finally, a simulation example is provided to illustrate the effectiveness of the present decentralized control scheme.

An examination of blood center structure and hospital customer satisfaction: what can centralized and decentralized blood centers learn from each other?

PubMed

Carden, Robert; DelliFraine, Jami L

2005-01-01

The cost of blood and blood products has increased rapidly over the last several years while the supply of available blood donors has simultaneously decreased. Higher blood costs and donor shortages have put a strain on the relationship between blood suppliers and their hospital customers. This study examines the association between blood center centralization or decentralization and several aspects of hospital satisfaction. Centralized and decentralized blood centers have significant differences in various aspects of hospital customer satisfaction. Advantages and disadvantages of the two structures are discussed, as well as areas for future research.

Decentralized stochastic control

NASA Technical Reports Server (NTRS)

Speyer, J. L.

1980-01-01

Decentralized stochastic control is characterized by being decentralized in that the information to one controller is not the same as information to another controller. The system including the information has a stochastic or uncertain component. This complicates the development of decision rules which one determines under the assumption that the system is deterministic. The system is dynamic which means the present decisions affect future system responses and the information in the system. This circumstance presents a complex problem where tools like dynamic programming are no longer applicable. These difficulties are discussed from an intuitive viewpoint. Particular assumptions are introduced which allow a limited theory which produces mechanizable affine decision rules.

Effect of political decentralization and female leadership on institutional births and child mortality in rural Bihar, India.

PubMed

Kumar, Santosh; Prakash, Nishith

2017-07-01

In this paper, we investigate the impacts of political decentralization and women reservation in local governance on institutional births and child mortality in the state of Bihar, India. Using the difference-in-differences methodology, we find a significant positive association between political decentralization and institutional births. We also find that the increased participation of women at local governance led to an increased survival rate of children belonging to richer households. We argue that our results are consistent with female leaders having policy preference for women and child well-being. Copyright © 2017 Elsevier Ltd. All rights reserved.