WorldWideScience

Sample records for optimizing metapopulation sustainability

  1. Optimizing metapopulation sustainability through a checkerboard strategy.

    Science.gov (United States)

    Zion, Yossi Ben; Yaari, Gur; Shnerb, Nadav M

    2010-01-22

    The persistence of a spatially structured population is determined by the rate of dispersal among habitat patches. If the local dynamic at the subpopulation level is extinction-prone, the system viability is maximal at intermediate connectivity where recolonization is allowed, but full synchronization that enables correlated extinction is forbidden. Here we developed and used an algorithm for agent-based simulations in order to study the persistence of a stochastic metapopulation. The effect of noise is shown to be dramatic, and the dynamics of the spatial population differs substantially from the predictions of deterministic models. This has been validated for the stochastic versions of the logistic map, the Ricker map and the Nicholson-Bailey host-parasitoid system. To analyze the possibility of extinction, previous studies were focused on the attractiveness (Lyapunov exponent) of stable solutions and the structure of their basin of attraction (dependence on initial population size). Our results suggest that these features are of secondary importance in the presence of stochasticity. Instead, optimal sustainability is achieved when decoherence is maximal. Individual-based simulations of metapopulations of different sizes, dimensions and noise types, show that the system's lifetime peaks when it displays checkerboard spatial patterns. This conclusion is supported by the results of a recently published Drosophila experiment. The checkerboard strategy provides a technique for the manipulation of migration rates (e.g., by constructing corridors) in order to affect the persistence of a metapopulation. It may be used in order to minimize the risk of extinction of an endangered species, or to maximize the efficiency of an eradication campaign.

  2. Optimizing metapopulation sustainability through a checkerboard strategy.

    Directory of Open Access Journals (Sweden)

    Yossi Ben Zion

    2010-01-01

    Full Text Available The persistence of a spatially structured population is determined by the rate of dispersal among habitat patches. If the local dynamic at the subpopulation level is extinction-prone, the system viability is maximal at intermediate connectivity where recolonization is allowed, but full synchronization that enables correlated extinction is forbidden. Here we developed and used an algorithm for agent-based simulations in order to study the persistence of a stochastic metapopulation. The effect of noise is shown to be dramatic, and the dynamics of the spatial population differs substantially from the predictions of deterministic models. This has been validated for the stochastic versions of the logistic map, the Ricker map and the Nicholson-Bailey host-parasitoid system. To analyze the possibility of extinction, previous studies were focused on the attractiveness (Lyapunov exponent of stable solutions and the structure of their basin of attraction (dependence on initial population size. Our results suggest that these features are of secondary importance in the presence of stochasticity. Instead, optimal sustainability is achieved when decoherence is maximal. Individual-based simulations of metapopulations of different sizes, dimensions and noise types, show that the system's lifetime peaks when it displays checkerboard spatial patterns. This conclusion is supported by the results of a recently published Drosophila experiment. The checkerboard strategy provides a technique for the manipulation of migration rates (e.g., by constructing corridors in order to affect the persistence of a metapopulation. It may be used in order to minimize the risk of extinction of an endangered species, or to maximize the efficiency of an eradication campaign.

  3. Optimizing Hybrid Spreading in Metapopulations

    CERN Document Server

    Zhang, Changwang; Cox, Ingemar J; Chain, Benjamin M

    2014-01-01

    Epidemic spreading phenomena are ubiquitous in nature and society. Examples include the spreading of diseases, information, and computer viruses. Epidemics can spread by \\textit{local spreading}, where infected nodes can only infect a limited set of direct target nodes and \\textit{global spreading}, where an infected node can infect every other node. In reality, many epidemics spread using a hybrid mixture of both types of spreading. In this study we develop a theoretical framework for studying hybrid epidemics, and examine the optimum balance between spreading mechanisms in terms of achieving the maximum outbreak size. In a metapopulation, made up of many weakly connected subpopulations, we show that one can calculate an optimal tradeoff between local and global spreading which will maximise the extent of the epidemic. As an example we analyse the 2008 outbreak of the Internet worm Conficker, which uses hybrid spreading to propagate through the internet. Our results suggests that the worm would have been eve...

  4. On optimal choices in increase of patch area and reduction of interpatch distance for metapopulation persistence

    NARCIS (Netherlands)

    Etienne, RS

    2004-01-01

    Metapopulation theory teaches that the viability of metapopulations may be enlarged by decreasing the probability of extinction of local populations, or by increasing the colonization probability of empty habitat patches. In a metapopulation model study it has recently been found that reducing the e

  5. Using optimal transport theory to estimate transition probabilities in metapopulation dynamics

    Science.gov (United States)

    Nichols, Jonathan M.; Spendelow, Jeffrey A.; Nichols, James

    2017-01-01

    This work considers the estimation of transition probabilities associated with populations moving among multiple spatial locations based on numbers of individuals at each location at two points in time. The problem is generally underdetermined as there exists an extremely large number of ways in which individuals can move from one set of locations to another. A unique solution therefore requires a constraint. The theory of optimal transport provides such a constraint in the form of a cost function, to be minimized in expectation over the space of possible transition matrices. We demonstrate the optimal transport approach on marked bird data and compare to the probabilities obtained via maximum likelihood estimation based on marked individuals. It is shown that by choosing the squared Euclidean distance as the cost, the estimated transition probabilities compare favorably to those obtained via maximum likelihood with marked individuals. Other implications of this cost are discussed, including the ability to accurately interpolate the population's spatial distribution at unobserved points in time and the more general relationship between the cost and minimum transport energy.

  6. Optimal and Sustainable Groundwater Extraction

    Directory of Open Access Journals (Sweden)

    Christopher A. Wada

    2010-08-01

    Full Text Available With climate change exacerbating over-exploitation, groundwater scarcity looms as an increasingly critical issue worldwide. Minimizing the adverse effects of scarcity requires optimal as well as sustainable patterns of groundwater management. We review the many sustainable paths for groundwater extraction from a coastal aquifer and show how to find the particular sustainable path that is welfare maximizing. In some cases the optimal path converges to the maximum sustainable yield. For sufficiently convex extraction costs, the extraction path converges to an internal steady state above the level of maximum sustainable yield. We describe the challenges facing groundwater managers faced with multiple aquifers, the prospect of using recycled water, and the interdependence with watershed management. The integrated water management thus described results in less water scarcity and higher total welfare gains from groundwater use. The framework also can be applied to climate-change specifications about the frequency, duration, and intensity of precipitation by comparing before and after optimal management. For the case of South Oahu in Hawaii, the prospect of climate change increases the gains of integrated groundwater management.

  7. Optimizing Sustainable Geothermal Heat Extraction

    Science.gov (United States)

    Patel, Iti; Bielicki, Jeffrey; Buscheck, Thomas

    2016-04-01

    Geothermal heat, though renewable, can be depleted over time if the rate of heat extraction exceeds the natural rate of renewal. As such, the sustainability of a geothermal resource is typically viewed as preserving the energy of the reservoir by weighing heat extraction against renewability. But heat that is extracted from a geothermal reservoir is used to provide a service to society and an economic gain to the provider of that service. For heat extraction used for market commodities, sustainability entails balancing the rate at which the reservoir temperature renews with the rate at which heat is extracted and converted into economic profit. We present a model for managing geothermal resources that combines simulations of geothermal reservoir performance with natural resource economics in order to develop optimal heat mining strategies. Similar optimal control approaches have been developed for managing other renewable resources, like fisheries and forests. We used the Non-isothermal Unsaturated-saturated Flow and Transport (NUFT) model to simulate the performance of a sedimentary geothermal reservoir under a variety of geologic and operational situations. The results of NUFT are integrated into the optimization model to determine the extraction path over time that maximizes the net present profit given the performance of the geothermal resource. Results suggest that the discount rate that is used to calculate the net present value of economic gain is a major determinant of the optimal extraction path, particularly for shallower and cooler reservoirs, where the regeneration of energy due to the natural geothermal heat flux is a smaller percentage of the amount of energy that is extracted from the reservoir.

  8. Satisficing versus optimality: criteria for sustainability.

    Science.gov (United States)

    De Lara, Michel; Martinet, Vincent; Doyen, Luc

    2015-02-01

    Economic analysis addresses risk and long-term issues with discounted expected utility, focusing on optimality. Viability theory is rooted on satisfying sustainability constraints over time, focusing on feasibility. We build a bridge between these two approaches by establishing that viability is equivalent to an array of degenerate intertemporal optimization problems. First, we focus our attention on the deterministic case. We highlight the connections between the viability kernel and the minimum time of crisis. Carrying on, we lay out stochastic viability, turning the spotlight onto the notions of viable scenario and maximal viability probability. Our conceptual results bring the viability approach closer to the economic approach, especially in the stochastic case and regarding efficiency. We discuss the possible use of viability as a theoretical framework for biodiversity conservation, ecosystem management and climate change issues.

  9. Optimal control theory for sustainable environmental management.

    Science.gov (United States)

    Shastri, Yogendra; Diwekar, Urmila; Cabezas, Heriberto

    2008-07-15

    Sustainable ecosystem management aims to promote the structure and operation of the human components of the system while simultaneously ensuring the persistence of the structures and operation of the natural component. Given the complexity of this task owing to the diverse temporal and spatial scales and multidisciplinary interactions, a systems theory approach based on sound mathematical techniques is essential. Two important aspects of this approach are formulation of sustainability-based objectives and development of the management strategies. Fisher information can be used as the basis of a sustainability hypothesis to formulate relevant mathematical objectives for disparate systems, and optimal control theory provides the means to derive time-dependent management strategies. Partial correlation coefficient analysis is an efficient technique to identify the appropriate control variables for policy development. This paper represents a proof of concept for this approach using a model system that includes an ecosystem, humans, a very rudimentary industrial process, and a very simple agricultural system. Formulation and solution of the control problems help in identifying the effective management options which offer guidelines for policies in real systems. The results also emphasize that management using multiple parameters of different nature can be distinctly effective.

  10. Combined optimization model for sustainable energization strategy

    Science.gov (United States)

    Abtew, Mohammed Seid

    Access to energy is a foundation to establish a positive impact on multiple aspects of human development. Both developed and developing countries have a common concern of achieving a sustainable energy supply to fuel economic growth and improve the quality of life with minimal environmental impacts. The Least Developing Countries (LDCs), however, have different economic, social, and energy systems. Prevalence of power outage, lack of access to electricity, structural dissimilarity between rural and urban regions, and traditional fuel dominance for cooking and the resultant health and environmental hazards are some of the distinguishing characteristics of these nations. Most energy planning models have been designed for developed countries' socio-economic demographics and have missed the opportunity to address special features of the poor countries. An improved mixed-integer programming energy-source optimization model is developed to address limitations associated with using current energy optimization models for LDCs, tackle development of the sustainable energization strategies, and ensure diversification and risk management provisions in the selected energy mix. The Model predicted a shift from traditional fuels reliant and weather vulnerable energy source mix to a least cost and reliable modern clean energy sources portfolio, a climb on the energy ladder, and scored multifaceted economic, social, and environmental benefits. At the same time, it represented a transition strategy that evolves to increasingly cleaner energy technologies with growth as opposed to an expensive solution that leapfrogs immediately to the cleanest possible, overreaching technologies.

  11. Optimizing the Sustainment of U.S. Army Weapon Systems

    Science.gov (United States)

    2016-03-17

    64 OPTIMIZING SUSTAINMENT OF ARMY SYSTEMS 6 Chapter 1 - Optimizing the Sustainment of U.S. Army Weapon Systems In a paradigm shift from...past 13 years. The result has been the erosion of perishable maintenance skills. The Army must develop the most effective plan to sustain these...communities to study and effectively manage Army sustainment . One effort is the development of Maintenance Steering Groups (MSG) to perform extensive

  12. Connectivity dominates larval replenishment in a coastal reef fish metapopulation.

    Science.gov (United States)

    Saenz-Agudelo, Pablo; Jones, Geoffrey P; Thorrold, Simon R; Planes, Serge

    2011-10-07

    Direct estimates of larval retention and connectivity are essential to understand the structure and dynamics of marine metapopulations, and optimize the size and spacing of reserves within networks of marine-protected areas (MPAs). For coral reef fishes, while there are some empirical estimates of self-recruitment at isolated populations, exchange among sub-populations has been rarely quantified. Here, we used microsatellite DNA markers and a likelihood-based parentage analysis to assess the relative magnitude of self-recruitment and exchange among eight geographically distinct sub-populations of the panda clownfish Amphiprion polymnus along 30 km of coastline near Port Moresby, Papua New Guinea. In addition, we used an assignment/exclusion test to identify immigrants arriving from genetically distinct sources. Overall, 82 per cent of the juveniles were immigrants while 18 per cent were progeny of parents genotyped in our focal metapopulation. Of the immigrants, only 6 per cent were likely to be genetically distinct from the focal metapopulation, suggesting most of the connectivity is among sub-populations from a rather homogeneous genetic pool. Of the 18 per cent that were progeny of known adults, two-thirds dispersed among the eight sub-populations and only one-third settled back into natal sub-populations. Comparison of our data with previous studies suggested that variation in dispersal distances is likely to be influenced by the geographical setting and spacing of sub-populations.

  13. BOWOOSS: bionic optimized wood shells with sustainability

    Science.gov (United States)

    Pohl, Göran

    2011-04-01

    In architecture, shell construction is used for the most efficient, large spatial structures. Until now the use of wood rather played a marginal role, implementing those examples of architecture, although this material offers manifold advantages, especially against the background of accelerating shortage of resources and increasing requirements concerning the energy balance. Regarding the implementation of shells, nature offers a wide range of suggestions. The focus of the examinations is on the shells of marine plankton, especially of diatoms, whose richness in species promises the discovery of entirely new construction principles. The project is targeting at transferring advantageous features of these organisms on industrial produced, modular wood shell structures. Currently a transfer of these structures in CAD - models is taking place, helping to perform stress analysis by computational methods. Micro as well as macro structures are the subject of diverse consideration, allowing to draw the necessary conclusions for an architectural design. The insights of these tests are the basis for the development of physical models on different scales, which are used to verify the different approaches. Another important aim which is promoted in the project is to enhance the competitiveness of timber construction. Downsizing of the prefabricated structural elements leads to considerable lower transportation costs as abnormal loads can be avoided as far as possible and means of transportation can be loaded with higher efficiency so that an important contribution to the sustainability in the field of architecture can also be made.

  14. Bio-Inspired Optimization of Sustainable Energy Systems: A Review

    Directory of Open Access Journals (Sweden)

    Yu-Jun Zheng

    2013-01-01

    Full Text Available Sustainable energy development always involves complex optimization problems of design, planning, and control, which are often computationally difficult for conventional optimization methods. Fortunately, the continuous advances in artificial intelligence have resulted in an increasing number of heuristic optimization methods for effectively handling those complicated problems. Particularly, algorithms that are inspired by the principles of natural biological evolution and/or collective behavior of social colonies have shown a promising performance and are becoming more and more popular nowadays. In this paper we summarize the recent advances in bio-inspired optimization methods, including artificial neural networks, evolutionary algorithms, swarm intelligence, and their hybridizations, which are applied to the field of sustainable energy development. Literature reviewed in this paper shows the current state of the art and discusses the potential future research trends.

  15. Pareto optimization of an industrial ecosystem: sustainability maximization

    Directory of Open Access Journals (Sweden)

    J. G. M.-S. Monteiro

    2010-09-01

    Full Text Available This work investigates a procedure to design an Industrial Ecosystem for sequestrating CO2 and consuming glycerol in a Chemical Complex with 15 integrated processes. The Complex is responsible for the production of methanol, ethylene oxide, ammonia, urea, dimethyl carbonate, ethylene glycol, glycerol carbonate, β-carotene, 1,2-propanediol and olefins, and is simulated using UNISIM Design (Honeywell. The process environmental impact (EI is calculated using the Waste Reduction Algorithm, while Profit (P is estimated using classic cost correlations. MATLAB (The Mathworks Inc is connected to UNISIM to enable optimization. The objective is granting maximum process sustainability, which involves finding a compromise between high profitability and low environmental impact. Sustainability maximization is therefore understood as a multi-criteria optimization problem, addressed by means of the Pareto optimization methodology for trading off P vs. EI.

  16. Portfolio conservation of metapopulations under climate change.

    Science.gov (United States)

    Anderson, Sean C; Moore, Jonathan W; McClure, Michelle M; Dulvy, Nicholas K; Cooper, Andrew B

    2015-03-01

    Climate change is likely to lead to increasing population variability and extinction risk. Theoretically, greater population diversity should buffer against rising climate variability, and this theory is often invoked as a reason for greater conservation. However, this has rarely been quantified. Here we show how a portfolio approach to managing population diversity can inform metapopulation conservation priorities in a changing world. We develop a salmon metapopulation model in which productivity is driven by spatially distributed thermal tolerance and patterns of short- and long-term climate change. We then implement spatial conservation scenarios that control population carrying capacities and evaluate the metapopulation portfolios as a financial manager might: along axes of conservation risk and return. We show that preserving a diversity of thermal tolerances minimizes risk, given environmental stochasticity, and ensures persistence, given long-term environmental change. When the thermal tolerances of populations are unknown, doubling the number of populations conserved may nearly halve expected metapopulation variability. However, this reduction in variability can come at the expense of long-term persistence if climate change increasingly restricts available habitat, forcing ecological managers to balance society's desire for short-term stability and long-term viability. Our findings suggest the importance of conserving the processes that promote thermal-tolerance diversity, such as genetic diversity, habitat heterogeneity, and natural disturbance regimes, and demonstrate that diverse natural portfolios may be critical for metapopulation conservation in the face of increasing climate variability and change.

  17. Sustainable Data Evolution Technology for Power Grid Optimization

    Energy Technology Data Exchange (ETDEWEB)

    2017-10-09

    The SDET Tool is used to create open-access power grid data sets and facilitate updates of these data sets by the community. Pacific Northwest National Laboratory (PNNL) and its power industry and software vendor partners are developing an innovative sustainable data evolution technology (SDET) to create open-access power grid datasets and facilitate updates to these datasets by the power grid community. The objective is to make this a sustained effort within and beyond the ARPA-E GRID DATA program so that the datasets can evolve over time and meet the current and future needs for power grid optimization and potentially other applications in power grid operation and planning.

  18. Seabird metapopulations: searching for alternative breeding habitats

    NARCIS (Netherlands)

    Schippers, P.; Snep, R.P.H.; Schotman, A.G.M.; Jochem, R.; Stienen, E.W.M.; Slim, P.A.

    2009-01-01

    Today, many seabird species nest in port areas, which are also necessary for human economic activity. In this paper, we evaluate, using a metapopulation model, the possibilities for creating alternative breeding sites for the Common Tern (Sterna hirundo) in the Rhine¿Meuse¿Scheldt estuary. We explor

  19. Optimization of sustained release aceclofenac microspheres using response surface methodology

    Energy Technology Data Exchange (ETDEWEB)

    Deshmukh, Rameshwar K.; Naik, Jitendra B., E-mail: jitunaik@gmail.com

    2015-03-01

    Polymeric microspheres containing aceclofenac were prepared by single emulsion (oil-in-water) solvent evaporation method using response surface methodology (RSM). Microspheres were prepared by changing formulation variables such as the amount of Eudragit® RS100 and the amount of polyvinyl alcohol (PVA) by statistical experimental design in order to enhance the encapsulation efficiency (E.E.) of the microspheres. The resultant microspheres were evaluated for their size, morphology, E.E., and in vitro drug release. The amount of Eudragit® RS100 and the amount of PVA were found to be significant factors respectively for determining the E.E. of the microspheres. A linear mathematical model equation fitted to the data was used to predict the E.E. in the optimal region. Optimized formulation of microspheres was prepared using optimal process variables setting in order to evaluate the optimization capability of the models generated according to IV-optimal design. The microspheres showed high E.E. (74.14 ± 0.015% to 85.34 ± 0.011%) and suitably sustained drug release (minimum; 40% to 60%; maximum) over a period of 12 h. The optimized microspheres formulation showed E.E. of 84.87 ± 0.005 with small error value (1.39). The low magnitudes of error and the significant value of R{sup 2} in the present investigation prove the high prognostic ability of the design. The absence of interactions between drug and polymers was confirmed by Fourier transform infrared (FTIR) spectroscopy. Differential scanning calorimetry (DSC) and X-ray powder diffractometry (XRPD) revealed the dispersion of drug within microspheres formulation. The microspheres were found to be discrete, spherical with smooth surface. The results demonstrate that these microspheres could be promising delivery system to sustain the drug release and improve the E.E. thus prolong drug action and achieve the highest healing effect with minimal gastrointestinal side effects. - Highlights: • Aceclofenac microspheres

  20. Optimization of sustained release aceclofenac microspheres using response surface methodology.

    Science.gov (United States)

    Deshmukh, Rameshwar K; Naik, Jitendra B

    2015-03-01

    Polymeric microspheres containing aceclofenac were prepared by single emulsion (oil-in-water) solvent evaporation method using response surface methodology (RSM). Microspheres were prepared by changing formulation variables such as the amount of Eudragit® RS100 and the amount of polyvinyl alcohol (PVA) by statistical experimental design in order to enhance the encapsulation efficiency (E.E.) of the microspheres. The resultant microspheres were evaluated for their size, morphology, E.E., and in vitro drug release. The amount of Eudragit® RS100 and the amount of PVA were found to be significant factors respectively for determining the E.E. of the microspheres. A linear mathematical model equation fitted to the data was used to predict the E.E. in the optimal region. Optimized formulation of microspheres was prepared using optimal process variables setting in order to evaluate the optimization capability of the models generated according to IV-optimal design. The microspheres showed high E.E. (74.14±0.015% to 85.34±0.011%) and suitably sustained drug release (minimum; 40% to 60%; maximum) over a period of 12h. The optimized microspheres formulation showed E.E. of 84.87±0.005 with small error value (1.39). The low magnitudes of error and the significant value of R(2) in the present investigation prove the high prognostic ability of the design. The absence of interactions between drug and polymers was confirmed by Fourier transform infrared (FTIR) spectroscopy. Differential scanning calorimetry (DSC) and X-ray powder diffractometry (XRPD) revealed the dispersion of drug within microspheres formulation. The microspheres were found to be discrete, spherical with smooth surface. The results demonstrate that these microspheres could be promising delivery system to sustain the drug release and improve the E.E. thus prolong drug action and achieve the highest healing effect with minimal gastrointestinal side effects.

  1. Is local participation always optimal for sustainable action?

    DEFF Research Database (Denmark)

    Brandt, Urs Steiner; Svendsen, Gert Tinggaard

    2013-01-01

    . Why? Because as the number of participants grows, the more likely it is that the group will include individuals who have an extreme position and are unwilling to make compromises. Thus, the net gain of self-organization should be compared with those of its alternatives, for example voting, market......Is local participation always optimal for sustainable action? Here, Local Agenda 21 is a relevant case as it broadly calls for consensus-building among stakeholders. Consensus-building is, however, costly. We show that the costs of making local decisions are likely to rapidly exceed the benefits......-solutions, or not making any choices at all. Even though the informational value of meetings may be helpful to policy makers, the model shows that it also decreases as the number of participants increase. Overall, the result is a thought provoking scenario for Local Agenda 21 as it highlights the risk of less sustainable...

  2. Using strong sustainability to optimize electricity generation fuel mixes

    Energy Technology Data Exchange (ETDEWEB)

    Bishop, Justin D.K.; Amaratunga, Gehan A.J.; Rodriguez, Cuauhtemoc [University of Cambridge Department of Engineering, 9 JJ Thomson Avenue, Cambridge CB3 0FA, England (United Kingdom)

    2008-03-15

    This work represents a contribution to the field of sustainable electricity system design by using an optimization tool to specify the final mix composition, subject to the constraints of: emissions that are within the biocapacity of the region; a diverse and robust electricity supply system; and supply that at least meets current demand. The 25-country European Union (EU-25) is used as a case study. All the goals, save diversity, can be met by re-structuring the current fuel mix, thus maintaining current consumption levels. The diversity target is only met when consumption is reduced by 10-15% and the constraint on maximum material throughput is relaxed. Re-structuring the mix and reducing consumption is insufficient to achieve a sustainable EU carbon footprint. However, the solution proposed singlehandedly allows the EU to meet its Kyoto emissions target as well as its 2007 policy of a reduction of 20% in greenhouse gas emissions by 2020. (author)

  3. Optimal planning for the sustainable utilization of municipal solid waste

    Energy Technology Data Exchange (ETDEWEB)

    Santibañez-Aguilar, José Ezequiel [Chemical Engineering Department, Universidad Michoacana de San Nicolás de Hidalgo, Morelia, Michoacán 58060 (Mexico); Ponce-Ortega, José María, E-mail: jmponce@umich.mx [Chemical Engineering Department, Universidad Michoacana de San Nicolás de Hidalgo, Morelia, Michoacán 58060 (Mexico); Betzabe González-Campos, J. [Institute of Chemical and Biological Researches, Universidad Michoacana de San Nicolás de Hidalgo, Morelia, Michoacán 58060 (Mexico); Serna-González, Medardo [Chemical Engineering Department, Universidad Michoacana de San Nicolás de Hidalgo, Morelia, Michoacán 58060 (Mexico); El-Halwagi, Mahmoud M. [Chemical Engineering Department, Texas A and M University, College Station, TX 77843 (United States); Adjunct Faculty at the Chemical and Materials Engineering Department, Faculty of Engineering, King Abdulaziz University, P.O. Box 80204, Jeddah 21589 (Saudi Arabia)

    2013-12-15

    Highlights: • An optimization approach for the sustainable management of municipal solid waste is proposed. • The proposed model optimizes the entire supply chain network of a distributed system. • A case study for the sustainable waste management in the central-west part of Mexico is presented. • Results shows different interesting solutions for the case study presented. - Abstract: The increasing generation of municipal solid waste (MSW) is a major problem particularly for large urban areas with insufficient landfill capacities and inefficient waste management systems. Several options associated to the supply chain for implementing a MSW management system are available, however to determine the optimal solution several technical, economic, environmental and social aspects must be considered. Therefore, this paper proposes a mathematical programming model for the optimal planning of the supply chain associated to the MSW management system to maximize the economic benefit while accounting for technical and environmental issues. The optimization model simultaneously selects the processing technologies and their location, the distribution of wastes from cities as well as the distribution of products to markets. The problem was formulated as a multi-objective mixed-integer linear programing problem to maximize the profit of the supply chain and the amount of recycled wastes, where the results are showed through Pareto curves that tradeoff economic and environmental aspects. The proposed approach is applied to a case study for the west-central part of Mexico to consider the integration of MSW from several cities to yield useful products. The results show that an integrated utilization of MSW can provide economic, environmental and social benefits.

  4. Seasonal variance in P system models for metapopulations

    Institute of Scientific and Technical Information of China (English)

    Daniela Besozzi; Paolo Cazzaniga; Dario Pescini; Giancarlo Mauri

    2007-01-01

    Metapopulations are ecological models describing the interactions and the behavior of populations living in fragmented habitats. In this paper, metapopulations are modelled by means of dynamical probabilistic P systems, where additional structural features have been defined (e. g., a weighted graph associated with the membrane structure and the reduction of maximal parallelism). In particular, we investigate the influence of stochastic and periodic resource feeding processes, owing to seasonal variance, on emergent metapopulation dynamics.

  5. Empirical determinants of measles metapopulation dynamics in England and Wales.

    OpenAIRE

    Finkenstädt, B; Grenfell, B.

    1998-01-01

    A key issue in metapopulation dynamics is the relative impact of internal patch dynamics and coupling between patches. This problem can be addressed by analysing large spatiotemporal data sets, recording the local and global dynamics of metapopulations. In this paper, we analyse the dynamics of measles meta-populations in a large spatiotemporal case notification data set, collected during the pre-vaccination era in England and Wales. Specifically, we use generalized linear statistical models ...

  6. Contingency Contractor Optimization Phase 3 Sustainment Requirements Document Contingency Contractor Optimization Tool - Prototype

    Energy Technology Data Exchange (ETDEWEB)

    Bandlow, Alisa; Durfee, Justin David; Frazier, Christopher Rawls; Jones, Katherine A; Gearhart, Jared Lee

    2016-05-01

    This requirements document serves as an addendum to the Contingency Contractor Optimization Phase 2, Requirements Document [1] and Phase 3 Requirements Document [2]. The Phase 2 Requirements document focused on the high-level requirements for the tool. The Phase 3 Requirements document provided more detailed requirements to which the engineering prototype was built in Phase 3. This document will provide detailed requirements for features and enhancements being added to the production pilot in the Phase 3 Sustainment.

  7. Optimizing pyramided transgenic Bt crops for sustainable pest management.

    Science.gov (United States)

    Carrière, Yves; Crickmore, Neil; Tabashnik, Bruce E

    2015-02-01

    Transgenic crop pyramids producing two or more Bacillus thuringiensis (Bt) toxins that kill the same insect pest have been widely used to delay evolution of pest resistance. To assess the potential of pyramids to achieve this goal, we analyze data from 38 studies that report effects of ten Bt toxins used in transgenic crops against 15 insect pests. We find that compared with optimal low levels of insect survival, survival on currently used pyramids is often higher for both susceptible insects and insects resistant to one of the toxins in the pyramid. Furthermore, we find that cross-resistance and antagonism between toxins used in pyramids are common, and that these problems are associated with the similarity of the amino acid sequences of domains II and III of the toxins, respectively. This analysis should assist in future pyramid design and the development of sustainable resistance management strategies.

  8. Sustainable Optimization for Wastewater Treatment System Using PSF-HS

    Directory of Open Access Journals (Sweden)

    Zong Woo Geem

    2016-03-01

    Full Text Available The sustainability in a river with respect to water quality is critical because it is highly related with environmental pollution, economic expenditure, and public health. This study proposes a sustainability problem of wastewater treatment system for river ecosystem conservation which helps the healthy survival of the aquatic biota and human beings. This study optimizes the design of a wastewater treatment system using the parameter-setting-free harmony search algorithm, which does not require the existing tedious value-setting process for algorithm parameters. The real-scale system has three different options of wastewater treatment, such as filtration, nitrification, and diverted irrigation (fertilization, as well as two existing treatment processes (settling and biological oxidation. The objective of this system design is to minimize life cycle costs, including initial construction costs of those treatment options, while satisfying minimal dissolved oxygen requirements in the river, maximal nitrate-nitrogen concentration in groundwater, and a minimal nitrogen requirement for crop farming. Results show that the proposed technique could successfully find solutions without requiring a tedious setting process.

  9. Optimization Model to Enhance Sustainable Utilization of Resources

    Institute of Scientific and Technical Information of China (English)

    ZHAO Guo-hao; SHEN Tu-jing

    2002-01-01

    Resources are material foundation for sustainable development. To enhance resources utilization is the key factor for realizing sustainable development. Based on the idea of sustainable development, the paper establishes the model to effectively distribute resources and proposes a method for studies on sustainable development.

  10. Intermediate fragmentation per se provides stable predator-prey metapopulation dynamics.

    Science.gov (United States)

    Cooper, Jennifer K; Li, Jiqiu; Montagnes, David J S

    2012-08-01

    The extent to which a landscape is fragmented affects persistence of predator-prey dynamics. Increasing fragmentation concomitantly imposes conditions that stabilise and destabilise metapopulations. For the first time, we explicitly assessed the hypothesis that intermediate levels provide optimal conditions for stability. We examine four structural changes arising from increased fragmentation: increased fragment number; decreased fragment size; increased connectedness (corridors scaled to fragment); increased fragment heterogeneity (based on connectedness). Using the model predator-prey system (Didinium-Paramecium) we support our hypothesis, by examining replicated metapopulations dynamics at five fragmentation levels. Although both species became extinct without fragmentation, prey survived at low and high levels, and both survived at intermediate levels. By examining time to extinction, maximum abundances, and population asynchrony we conclude that fragmentation produces structural heterogeneity (independent of environmental heterogeneity), which influences stability. Our analysis suggests why some theoretical, field and microcosm studies present conflicting views of fragmentation effects on population persistence.

  11. Spatial and spatiotemporal variation in metapopulation structure affects population dynamics in a passively dispersing arthropod.

    Science.gov (United States)

    De Roissart, Annelies; Wang, Shaopeng; Bonte, Dries

    2015-11-01

    The spatial and temporal variation in the availability of suitable habitat within metapopulations determines colonization-extinction events, regulates local population sizes and eventually affects local population and metapopulation stability. Insights into the impact of such a spatiotemporal variation on the local population and metapopulation dynamics are principally derived from classical metapopulation theory and have not been experimentally validated. By manipulating spatial structure in artificial metapopulations of the spider mite Tetranychus urticae, we test to which degree spatial (mainland-island metapopulations) and spatiotemporal variation (classical metapopulations) in habitat availability affects the dynamics of the metapopulations relative to systems where habitat is constantly available in time and space (patchy metapopulations). Our experiment demonstrates that (i) spatial variation in habitat availability decreases variance in metapopulation size and decreases density-dependent dispersal at the metapopulation level, while (ii) spatiotemporal variation in habitat availability increases patch extinction rates, decreases local population and metapopulation sizes and decreases density dependence in population growth rates. We found dispersal to be negatively density dependent and overall low in the spatial variable mainland-island metapopulation. This demographic variation subsequently impacts local and regional population dynamics and determines patterns of metapopulation stability. Both local and metapopulation-level variabilities are minimized in mainland-island metapopulations relative to classical and patchy ones.

  12. Optimization of emergy sustainability index for biodiesel supply network design

    DEFF Research Database (Denmark)

    Ren, Jingzheng; Tan, Shiyu; Yang, Le

    2015-01-01

    sustainable design. In the proposed model, the emergy sustainability index of the whole biodiesel supply networks in a life cycle perspective is employed as the measure of the sustainability, and multiple feedstocks, multiple transport modes, multiple regions for biodiesel production and multiple distribution...... centers can be considered. After describing the process and mathematic framework of the model, an illustrative case was studied and demonstrated that the proposed methodology is feasible for finding the most sustainable design and planning of biodiesel supply chains....

  13. Variability in primary productivity determines metapopulation dynamics.

    Science.gov (United States)

    Fernández, Néstor; Román, Jacinto; Delibes, Miguel

    2016-04-13

    Temporal variability in primary productivity can change habitat quality for consumer species by affecting the energy levels available as food resources. However, it remains unclear how habitat-quality fluctuations may determine the dynamics of spatially structured populations, where the effects of habitat size, quality and isolation have been customarily assessed assuming static habitats. We present the first empirical evaluation on the effects of stochastic fluctuations in primary productivity--a major outcome of ecosystem functions--on the metapopulation dynamics of a primary consumer. A unique 13-year dataset from an herbivore rodent was used to test the hypothesis that inter-annual variations in primary productivity determine spatiotemporal habitat occupancy patterns and colonization and extinction processes. Inter-annual variability in productivity and in the growing season phenology significantly influenced habitat colonization patterns and occupancy dynamics. These effects lead to changes in connectivity to other potentially occupied habitat patches, which then feed back into occupancy dynamics. According to the results, the dynamics of primary productivity accounted for more than 50% of the variation in occupancy probability, depending on patch size and landscape configuration. Evidence connecting primary productivity dynamics and spatiotemporal population processes has broad implications for metapopulation persistence in fluctuating and changing environments.

  14. Formulation, optimization and evaluation of sustained release microsphere of ketoprofen

    Directory of Open Access Journals (Sweden)

    V Chirag Prajapati

    2012-01-01

    Full Text Available The objective of this study is to formulate ketoprofen loaded microspheres of Acrycoat S100 by an o/w emulsion solvent evaporation method. It potently inhibits the enzyme cyclooxygenase resulting in prostaglandin synthesis inhibition. Ketoprofen causes an irritation in the gastrointestinal mucous membrane and possesses a bitter taste and aftertaste. The half-life in plasma is about 1-2hrs. This makes ketoprofen a very good candidate for the formulation of controlled release dosage forms. Ketoprofen microspheres help to protect the gastric mucous membrane from drug irritation and to mask its taste. The prepared microspheres were evaluated for micromeritic properties, particle size, effect of surfactant concentration, percentage yield, incorporation efficiency, drug polymer compatibility (IR and DSC study, scanning electron microscopy and in vitro drug release. The microspheres produced exhibited good encapsulation efficiencies and micromeritic properties. Encapsulation efficiency of microsphere is around 78%. The mean diameters of microspheres were found in required micrometer range. The results of optimized formulations showed a narrow size distribution and smooth surface. The DSC and the FTIR analysis showed the absence of any potent incompatibility between the drug and the polymer. In-vitro release showed 86.4% drug release after 12 hours. Results of present study suggest that Acrycoat S100 loaded microsphere of ketoprofen can be successfully designed to develop sustained drug delivery system. The solvent evaporation method is a suitable technique for the preparation of Acrycoat S100 microspheres for controlling the release of Ketoprofen for a prolonged duration.

  15. Applications of Rapid Evaluation of Metapopulation Persistence (REMP) in Conservation Planning for Vulnerable Fauna Species

    Science.gov (United States)

    Taylor, Subhashni; Drielsma, Michael; Taylor, Robert; Kumar, Lalit

    2016-06-01

    In many regions species are declining due to fragmentation and loss of habitat. If species persistence is to be achieved, ecologically informed, effective conservation action is required. Yet it remains a challenge to identify optimal places in a landscape to direct habitat reconstruction and management. Rather than relying on individual landscape metrics, process-based regional scale assessment methodology is needed that focuses primarily on species persistence. This means integrating, according to species' ecology, habitat extent, suitability, quality and spatial configuration. The rapid evaluation of metapopulation persistence (REMP) methodology has been developed for this purpose. However, till now no practical conservation planning application of REMP has been described. By integration of expert ecological knowledge, we extended REMP's capabilities to prioritize conservation action for a highly modified agricultural region of central NSW, Australia based on the metapopulation ecology of 34 fauna species. The region's current capacity to support the species was evaluated in relation to the pre-European state for which there was known viability. Six of the species were found to currently have insufficient habitat to support viable populations. Seeking locations to maximize overall improvement in viability for these species, we prioritized conservation action to locations near the threshold of metapopulation persistence.

  16. Modeling vaccination in a heterogeneous metapopulation system

    Science.gov (United States)

    Lachiany, Menachem

    2016-09-01

    We present here a multicity SIS epidemic model with vaccination. The model describes the dynamics of heterogeneous metapopulations that contain imperfectly vaccinated individuals. The effect of vaccination on heterogeneous multicity models has not been previously studied. We show that under very generic conditions, the epidemic threshold does not depend on the diffusion coefficient of the vaccinated individuals, but it does depend on the diffusion coefficient of the infected population. We then show, using a novel methodology, that the reproduction number is determined by the homogeneous model parameters and by the maximal number of neighbors a city can have, when the diffusion coefficient of the infected population is low. Finally, we present numerical simulations to support the analytical results.

  17. Plague metapopulation dynamics in a natural reservoir

    DEFF Research Database (Denmark)

    Davis, S; Klassovskiy, N; Ageyev, V

    2007-01-01

    The ecology of plague (Yersinia pestis infection) in its ancient foci in Central Asia remains poorly understood. We present field data from two sites in Kazakhstan where the great gerbil (Rhombomys opimus) is the major natural host. Family groups inhabit and defend burrow systems spaced throughout...... the landscape, such that the host population may be considered a metapopulation, with each occupied burrow system a subpopulation. We examine plague transmission within and between family groups and its effect on survival. Transmission of plague occurred disproportionately within family groups although not all...... gerbils became infected once plague entered a burrow system. There were no spatial patterns to suggest that family groups in close proximity to infected burrow systems were more at risk of infection than those far away. At one site, infection increased the chances of burrow-system extinction. Overall...

  18. Watershed Scale Optimization to Meet Sustainable Cellulosic Energy Crop Demand

    Energy Technology Data Exchange (ETDEWEB)

    Chaubey, Indrajeet [Purdue Univ., West Lafayette, IN (United States); Cibin, Raj [Purdue Univ., West Lafayette, IN (United States); Bowling, Laura [Purdue Univ., West Lafayette, IN (United States); Brouder, Sylvie [Purdue Univ., West Lafayette, IN (United States); Cherkauer, Keith [Purdue Univ., West Lafayette, IN (United States); Engel, Bernard [Purdue Univ., West Lafayette, IN (United States); Frankenberger, Jane [Purdue Univ., West Lafayette, IN (United States); Goforth, Reuben [Purdue Univ., West Lafayette, IN (United States); Gramig, Benjamin [Purdue Univ., West Lafayette, IN (United States); Volenec, Jeffrey [Purdue Univ., West Lafayette, IN (United States)

    2017-03-24

    The overall goal of this project was to conduct a watershed-scale sustainability assessment of multiple species of energy crops and removal of crop residues within two watersheds (Wildcat Creek, and St. Joseph River) representative of conditions in the Upper Midwest. The sustainability assessment included bioenergy feedstock production impacts on environmental quality, economic costs of production, and ecosystem services.

  19. Safe and Sustainable: Optimizing Material Flows in a Circular Economy

    DEFF Research Database (Denmark)

    Fantke, Peter

    life cycles.However, a circular economy is only viable if it is both safe and sustainable. The dilemma is that sustainable does not necessarily imply safe and vice versa. When minimizing exposure to harmful chemicals in consumer products (safe), we often use more energy-demanding alternative solutions...... (unsustainable). When maximizing resource use efficiency and reducing carbon and other emissions through recycling (sustainable), direct consumer exposure is often increased through cross-contamination of recycled materials (unsafe). Hence, circular economy currently fails to unite the required expertise......Increasing the sustainability of a globally connected economy is gaining wide attention in a world with limited natural resources and growing chemical pollution. The circular economy has emerged as away to reduce carbon and other emissions, while increasing resource efficiency over several product...

  20. Optimal and Sustainable Exchange Rate Regimes; A Simple Game-Theoretic Approach

    OpenAIRE

    Masahiro Kawai

    1992-01-01

    This paper examines the question of how to design an optimal and sustainable exchange rate regime in a world economy of two interdependent countries. It develops a Barro-Gordon type two-country model and compares noncooperative equilibria under different assumptions of monetary policy credibility and different exchange rate regimes. Using a two-stage game approach to the strategic choice of policy instruments, it identifies optimal (in a Pare to sense) and sustainable (self-enforcing) exchang...

  1. Comparison of reintroduction and enhancement effects on metapopulation viability

    Science.gov (United States)

    Halsey, Samniqueka J; Bell, Timothy J.; McEachern, Kathryn; Pavlovic, Noel B.

    2015-01-01

    Metapopulation viability depends upon a balance of extinction and colonization of local habitats by a species. Mechanisms that can affect this balance include physical characteristics related to natural processes (e.g. succession) as well as anthropogenic actions. Plant restorations can help to produce favorable metapopulation dynamics and consequently increase viability; however, to date no studies confirm this is true. Population viability analysis (PVA) allows for the use of empirical data to generate theoretical future projections in the form of median time to extinction and probability of extinction. In turn, PVAs can inform and aid the development of conservation, recovery, and management plans. Pitcher's thistle (Cirsium pitcheri) is a dune endemic that exhibited metapopulation dynamics. We projected viability of three natural and two restored populations with demographic data spanning 15–23 years to determine the degree the addition of reintroduced population affects metapopulation viability. The models were validated by comparing observed and projected abundances and adjusting parameters associated with demographic and environmental stochasticity to improve model performance. Our chosen model correctly predicted yearly population abundance for 60% of the population-years. Using that model, 50-year projections showed that the addition of reintroductions increases metapopulation viability. The reintroduction that simulated population performance in early-successional habitats had the maximum benefit. In situ enhancements of existing populations proved to be equally effective. This study shows that restorations can facilitate and improve metapopulation viability of species dependent on metapopulation dynamics for survival with long-term persistence of C. pitcheri in Indiana likely to depend on continued active management.

  2. SUSTAIN:Urban Modeling Systems Integrating Optimization and Economics

    Science.gov (United States)

    The System for Urban Stormwater Treatment and Analysis INtegration (SUSTAIN) was developed by the U.S. Environmental Protection Agency to support practitioners in developing cost-effective management plans for municipal storm water programs and evaluating and selecting Best Manag...

  3. Sustainable Tourism Products Distribution: Optimal Pricing and Branding Strategies

    OpenAIRE

    Ogonowska, Malgorzata

    2011-01-01

    International audience; This paper considers the issue of sustainable tourism products distribution by an intermediary, offering as well traditional, i.e. not necessarily environmentally friendly, products. Given the complexity of demand's heterogeneity and its characteristics, the intermediary faces multiple strategic choices. Considering the contributions of related literature, this paper's positioning is indicated. Then, in the third section the motivations of this study are presented, fol...

  4. How Levins’ dynamics emerges from a Ricker metapopulation model

    KAUST Repository

    Elías-Wolff, F.

    2015-09-24

    Understanding the dynamics of metapopulations close to extinction is of vital importance for management. Levins-like models, in which local patches are treated as either occupied or empty, have been used extensively to explore the extinction dynamics of metapopulations, but they ignore the important role of local population dynamics. In this paper, we consider a stochastic metapopulation model where local populations follow a stochastic, density-dependent dynamics (the Ricker model), and use this framework to investigate the behaviour of the metapopulation on the brink of extinction. We determine under which circumstances the metapopulation follows a time evolution consistent with Levins’ dynamics. We derive analytical expressions for the colonisation and extinction rates (c and e) in Levins-type models in terms of reproduction, survival and dispersal parameters of the local populations, providing an avenue to parameterising Levins-like models from the type of information on local demography that is available for a number of species. To facilitate applying our results, we provide a numerical algorithm for computing c and e.

  5. Sustaining Action and Optimizing Entropy: Coupling Efficiency for Energy and the Sustainability of Global Ecosystems

    Science.gov (United States)

    Rose, Michael T.; Crossan, Angus N.; Kennedy, Ivan R.

    2008-01-01

    Consideration of the property of action is proposed to provide a more meaningful definition of efficient energy use and sustainable production in ecosystems. Action has physical dimensions similar to angular momentum, its magnitude varying with mass, spatial configuration and relative motion. In this article, the relationship of action to…

  6. Metapopulation dynamics enable persistence of influenza A, including A/H5N1, in poultry.

    Science.gov (United States)

    Hosseini, Parviez Rana; Fuller, Trevon; Harrigan, Ryan; Zhao, Delong; Arriola, Carmen Sofia; Gonzalez, Armandoe; Miller, Matthew Joshua; Xiao, Xiangming; Smith, Tom B; Jones, Jamie Holland; Daszak, Peter

    2013-01-01

    Highly pathogenic influenza A/H5N1 has persistently but sporadically caused human illness and death since 1997. Yet it is still unclear how this pathogen is able to persist globally. While wild birds seem to be a genetic reservoir for influenza A, they do not seem to be the main source of human illness. Here, we highlight the role that domestic poultry may play in maintaining A/H5N1 globally, using theoretical models of spatial population structure in poultry populations. We find that a metapopulation of moderately sized poultry flocks can sustain the pathogen in a finite poultry population for over two years. Our results suggest that it is possible that moderately intensive backyard farms could sustain the pathogen indefinitely in real systems. This fits a pattern that has been observed from many empirical systems. Rather than just employing standard culling procedures to control the disease, our model suggests ways that poultry production systems may be modified.

  7. Contingency Contractor Optimization Phase 3 Sustainment Platform Requirements - Contingency Contractor Optimization Tool - Prototype

    Energy Technology Data Exchange (ETDEWEB)

    Durfee, Justin David [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Frazier, Christopher Rawls [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Bandlow, Alisa [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Gearhart, Jared Lee [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Jones, Katherine A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2016-06-01

    Sandia National Laboratories (Sandia) is in Phase 3 Sustainment of development of a prototype tool, currently referred to as the Contingency Contractor Optimization Tool - Prototype (CCOTP), under the direction of OSD Program Support. CCOT-P is intended to help provide senior Department of Defense (DoD) leaders with comprehensive insight into the global availability, readiness and capabilities of the Total Force Mix. The CCOT-P will allow senior decision makers to quickly and accurately assess the impacts, risks and mitigating strategies for proposed changes to force/capabilities assignments, apportionments and allocations options, focusing specifically on contingency contractor planning. During Phase 2 of the program, conducted during fiscal year 2012, Sandia developed an electronic storyboard prototype of the Contingency Contractor Optimization Tool that can be used for communication with senior decision makers and other Operational Contract Support (OCS) stakeholders. Phase 3 used feedback from demonstrations of the electronic storyboard prototype to develop an engineering prototype for planners to evaluate. Sandia worked with the DoD and Joint Chiefs of Staff strategic planning community to get feedback and input to ensure that the engineering prototype was developed to closely align with future planning needs. The intended deployment environment was also a key consideration as this prototype was developed. Initial release of the engineering prototype was done on servers at Sandia in the middle of Phase 3. In 2013, the tool was installed on a production pilot server managed by the OUSD(AT&L) eBusiness Center. The purpose of this document is to specify the CCOT-P engineering prototype platform requirements as of May 2016. Sandia developed the CCOT-P engineering prototype using common technologies to minimize the likelihood of deployment issues. CCOT-P engineering prototype was architected and designed to be as independent as possible of the major deployment

  8. Optimal planning for the sustainable utilization of municipal solid waste.

    Science.gov (United States)

    Santibañez-Aguilar, José Ezequiel; Ponce-Ortega, José María; Betzabe González-Campos, J; Serna-González, Medardo; El-Halwagi, Mahmoud M

    2013-12-01

    The increasing generation of municipal solid waste (MSW) is a major problem particularly for large urban areas with insufficient landfill capacities and inefficient waste management systems. Several options associated to the supply chain for implementing a MSW management system are available, however to determine the optimal solution several technical, economic, environmental and social aspects must be considered. Therefore, this paper proposes a mathematical programming model for the optimal planning of the supply chain associated to the MSW management system to maximize the economic benefit while accounting for technical and environmental issues. The optimization model simultaneously selects the processing technologies and their location, the distribution of wastes from cities as well as the distribution of products to markets. The problem was formulated as a multi-objective mixed-integer linear programing problem to maximize the profit of the supply chain and the amount of recycled wastes, where the results are showed through Pareto curves that tradeoff economic and environmental aspects. The proposed approach is applied to a case study for the west-central part of Mexico to consider the integration of MSW from several cities to yield useful products. The results show that an integrated utilization of MSW can provide economic, environmental and social benefits.

  9. A fuzzy multi-objective optimization model for sustainable reverse logistics network design

    DEFF Research Database (Denmark)

    Govindan, Kannan; Paam, Parichehr; Abtahi, Amir Reza

    2016-01-01

    a multi-echelon multi-period multi-objective model for a sustainable reverse logistics network. To reflect all aspects of sustainability, we try to minimize the present value of costs, as well as environmental impacts, and optimize the social responsibility as objective functions of the model. In order......Decreasing the environmental impact, increasing the degree of social responsibility, and considering the economic motivations of organizations are three significant features in designing a reverse logistics network under sustainability respects. Developing a model, which can simultaneously consider...

  10. Sustainable development through continuous optimization; Nachhaltige Entwicklung durch kontinuierliche Optimierung

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2011-07-01

    Lafarge operates one of Germany's most modern cement plants in Woessingen (Fig. 1). With the changeover from the semi-dry (Lepol) process to the dry process, which was completed in 2009 after only 17 months, the products were improved, the emissions were significantly reduced and the fuel mix was optimized. ZKG INTERNATIONAL has talked to the plant manager, Lutz Weber, about his experience with operating the new plant (see webcode ZKG0M6RR). Continuous optimization and modernization is traditional at Woessingen. Over the years this has enabled it to maintain its competitiveness and improve it still further. An open door day was held in September 2010 on the 60{sup th} anniversary of the cement plant at Woessingen to which politicians, neighbours and customers were invited to see the current state of the plant for themselves. Thanks to the new production line with a 5-stage cyclone preheater with calciner and combustion chamber from A TEC (Fig. 2) the way is open for a successful future for the Lafarge plant at Woessingen. (orig.)

  11. Solar water heating for aquaculture : optimizing design for sustainability

    Energy Technology Data Exchange (ETDEWEB)

    McDonald, M.; Thwaites, J. [Taylor Munro Energy Systems Inc., Delta, BC (Canada)

    2003-08-01

    This paper presents the results of a solar water heating project at Redfish Ranch, the first Tilapia tropical fish farm in British Columbia. The fish are raised in land-based tanks, eliminating the risk of contamination of local ecosystems. As a tropical species, they requires warm water. Natural gas or propane boilers are typically used to maintain tank temperatures at 26 to 28 degrees C. Redfish Ranch uses solar energy to add heat to the fish tanks, thereby reducing fossil-fuel combustion and greenhouse gas emissions. This unique building-integrated solar system is improving the environmental status of of this progressive industrial operation by offsetting fossil-fuel consumption. The system was relatively low cost, although substantial changes had to be made to the roof of the main building. The building-integrated design of the solar water heating system has reduced operating costs, generated local employment, and shows promise of future activity. As such, it satisfies the main criteria for sustainability. 7 refs.

  12. Spatial Optimization of Future Urban Development with Regards to Climate Risk and Sustainability Objectives.

    Science.gov (United States)

    Caparros-Midwood, Daniel; Barr, Stuart; Dawson, Richard

    2017-02-23

    Future development in cities needs to manage increasing populations, climate-related risks, and sustainable development objectives such as reducing greenhouse gas emissions. Planners therefore face a challenge of multidimensional, spatial optimization in order to balance potential tradeoffs and maximize synergies between risks and other objectives. To address this, a spatial optimization framework has been developed. This uses a spatially implemented genetic algorithm to generate a set of Pareto-optimal results that provide planners with the best set of trade-off spatial plans for six risk and sustainability objectives: (i) minimize heat risks, (ii) minimize flooding risks, (iii) minimize transport travel costs to minimize associated emissions, (iv) maximize brownfield development, (v) minimize urban sprawl, and (vi) prevent development of greenspace. The framework is applied to Greater London (U.K.) and shown to generate spatial development strategies that are optimal for specific objectives and differ significantly from the existing development strategies. In addition, the analysis reveals tradeoffs between different risks as well as between risk and sustainability objectives. While increases in heat or flood risk can be avoided, there are no strategies that do not increase at least one of these. Tradeoffs between risk and other sustainability objectives can be more severe, for example, minimizing heat risk is only possible if future development is allowed to sprawl significantly. The results highlight the importance of spatial structure in modulating risks and other sustainability objectives. However, not all planning objectives are suited to quantified optimization and so the results should form part of an evidence base to improve the delivery of risk and sustainability management in future urban development. © 2017 The Authors Risk Analysis published by Wiley Periodicals, Inc. on behalf of Society for Risk Analysis.

  13. Fenced and Fragmented: Conservation Value of Managed Metapopulations.

    Directory of Open Access Journals (Sweden)

    Susan M Miller

    Full Text Available Population fragmentation is threatening biodiversity worldwide. Species that once roamed vast areas are increasingly being conserved in small, isolated areas. Modern management approaches must adapt to ensure the continued survival and conservation value of these populations. In South Africa, a managed metapopulation approach has been adopted for several large carnivore species, all protected in isolated, relatively small, reserves that are fenced. As far as possible these approaches are based on natural metapopulation structures. In this network, over the past 25 years, African lions (Panthera leo were reintroduced into 44 fenced reserves with little attention given to maintaining genetic diversity. To examine the situation, we investigated the current genetic provenance and diversity of these lions. We found that overall genetic diversity was similar to that in a large national park, and included a mixture of four different southern African evolutionarily significant units (ESUs. This mixing of ESUs, while not ideal, provides a unique opportunity to study the impact of mixing ESUs over the long term. We propose a strategic managed metapopulation plan to ensure the maintenance of genetic diversity and improve the long-term conservation value of these lions. This managed metapopulation approach could be applied to other species under similar ecological constraints around the globe.

  14. Fuel Consumption Analysis and Optimization of a Sustainable Energy System for a 100% Renewables Smart House

    DEFF Research Database (Denmark)

    Craciun, Vasile Simion; Blarke, Morten; Trifa, Viorel

    2012-01-01

    . In case of renewable energies, one main challenge is the discontinuity of generation which can be solved with planning and control optimization methods. The results of the economic analysis and the feasibility of the sustainable energy system for a 100% renewables SH show that this could be possible...

  15. Achieving true sustainability of zoo populations.

    Science.gov (United States)

    Lacy, Robert C

    2013-01-01

    For the last 30 years, cooperative management of irreplaceable animal populations in zoos and aquariums has focused primarily on the goal of minimizing genetic decay within defined time frames, and large advances have been made in technologies to optimize genetic management of closed populations. However, recent analyses have shown that most zoo programs are not projected to meet their stated goals. This has been described as a lack of achieving "sustainability" of the populations, yet by definition a goal of managed decay is not a plan for sustainability. True sustainability requires management of the resource in manner that does not deplete its value for the future. Achieving such sustainability for many managed populations may require changing from managing isolated populations to managing populations that are part of a broader metapopulation, with carefully considered exchange between populations across a spectrum of ex situ to in situ. Managing zoo populations as components of comprehensive conservation strategies for the species will require research on determinants of various kinds of genetic, physiological, behavioral, and morphological variation and their roles in population viability, development of an array of management techniques and tools, training of population managers in metapopulation management and integrated conservation planning, and projections of impacts of management strategies on the viability of the captive populations and all populations that are interactively managed or affected. Such a shift in goals and methods would result in zoo population management being an ongoing part of species conservation rather than short-term or isolated from species conservation. Zoo Biol. 32:19-26, 2013. © 2012 Wiley Periodicals, Inc.

  16. Contingency Contractor Optimization Phase 3 Sustainment Software Design Document - Contingency Contractor Optimization Tool - Prototype

    Energy Technology Data Exchange (ETDEWEB)

    Durfee, Justin David; Frazier, Christopher Rawls; Bandlow, Alisa; Jones, Katherine A

    2016-05-01

    This document describes the final software design of the Contingency Contractor Optimization Tool - Prototype. Its purpose is to provide the overall architecture of the software and the logic behind this architecture. Documentation for the individual classes is provided in the application Javadoc. The Contingency Contractor Optimization project is intended to address Department of Defense mandates by delivering a centralized strategic planning tool that allows senior decision makers to quickly and accurately assess the impacts, risks, and mitigation strategies associated with utilizing contract support. The Contingency Contractor Optimization Tool - Prototype was developed in Phase 3 of the OSD ATL Contingency Contractor Optimization project to support strategic planning for contingency contractors. The planning tool uses a model to optimize the Total Force mix by minimizing the combined total costs for selected mission scenarios. The model optimizes the match of personnel types (military, DoD civilian, and contractors) and capabilities to meet mission requirements as effectively as possible, based on risk, cost, and other requirements.

  17. DETERMINATION OF THE OPTIMAL CAPITAL INVESTMENTS TO ENSURE THE SUSTAINABLE DEVELOPMENT OF THE RAILWAY

    Directory of Open Access Journals (Sweden)

    O. I. Kharchenko

    2015-04-01

    Full Text Available Purpose. Every year more attention is paid for the theoretical and practical issue of sustainable development of railway transport. But today the mechanisms of financial support of this development are poorly understood. Therefore, the aim of this article is to determine the optimal investment allocation to ensure sustainable development of the railway transport on the example of State Enterprise «Prydniprovsk Railway» and the creation of preconditions for the mathematical model development. Methodology. The ensuring task for sustainable development of railway transport is solved on the basis of the integral indicator of sustainable development effectiveness and defined as the maximization of this criterion. The optimization of measures technological and technical characters are proposed to carry out for increasing values of the integral performance measure components. To the optimization activities of technological nature that enhance the performance criteria belongs: optimization of the number of train and shunting locomotives, optimization of power handling mechanisms at the stations, optimization of routes of train flows. The activities related to the technical nature include: modernization of railways in the direction of their electrification and modernization of the running gear and coupler drawbars of rolling stock, as well as means of separators mechanization at stations to reduce noise impacts on the environment. Findings. The work resulted in the optimal allocation of investments to ensure the sustainable development of railway transportation of State Enterprise «Prydniprovsk Railway». This allows providing such kind of railway development when functioning of State Enterprise «Prydniprovsk Railway» is characterized by a maximum value of the integral indicator of efficiency. Originality. The work was reviewed and the new approach was proposed to determine the optimal allocation of capital investments to ensure sustainable

  18. Integration of Large-Scale Optimization and Game Theory for Sustainable Water Quality Management

    Science.gov (United States)

    Tsao, J.; Li, J.; Chou, C.; Tung, C.

    2009-12-01

    Sustainable water quality management requires total mass control in pollutant discharge based on both the principles of not exceeding assimilative capacity in a river and equity among generations. The stream assimilative capacity is the carrying capacity of a river for the maximum waste load without violating the water quality standard and the spirit of total mass control is to optimize the waste load allocation in subregions. For the goal of sustainable watershed development, this study will use large-scale optimization theory to optimize the profit, and find the marginal values of loadings as reference of the fair price and then the best way to get the equilibrium by water quality trading for the whole of watershed will be found. On the other hand, game theory plays an important role to maximize both individual and entire profits. This study proves the water quality trading market is available in some situation, and also makes the whole participants get a better outcome.

  19. Abiotic and biotic interactions determine whether increased colonization is beneficial or detrimental to metapopulation management.

    Science.gov (United States)

    Southwell, Darren M; Rhodes, Jonathan R; McDonald-Madden, Eve; Nicol, Sam; Helmstedt, Kate J; McCarthy, Michael A

    2016-06-01

    Increasing the colonization rate of metapopulations can improve persistence, but can also increase exposure to threats. To make good decisions, managers must understand whether increased colonization is beneficial or detrimental to metapopulation persistence. While a number of studies have examined interactions between metapopulations, colonization, and threats, they have assumed that threat dynamics respond linearly to changes in colonization. Here, we determined when to increase colonization while explicitly accounting for non-linear dependencies between a metapopulation and its threats. We developed patch occupancy metapopulation models for species susceptible to abiotic, generalist, and specialist threats and modeled the total derivative of the equilibrium proportion of patches occupied by each metapopulation with respect to the colonization rate. By using the total derivative, we developed a rule for determining when to increase metapopulation colonization. This rule was applied to a simulated metapopulation where the dynamics of each threat responded to increased colonization following a power function. Before modifying colonization, we show that managers must understand: (1) whether a metapopulation is susceptible to a threat; (2) the type of threat acting on a metapopulation; (3) which component of threat dynamics might depend on colonization, and; (4) the likely response of a threat-dependent variable to changes in colonization. The sensitivity of management decisions to these interactions increases uncertainty in conservation planning decisions.

  20. Dispersal, environmental forcing, and parasites combine to affect metapopulation synehrony and stability.

    Science.gov (United States)

    Duncan, Alison B; Gonzalez, Andrew; Kaltz, Oliver

    2015-01-01

    Dispersal can have positive and negative effects on metapopulation stability and persistence. One prediction is that high levels of dispersal synchronize density fluctuations between subpopulations. However, little is still known about how biotic and abiotic factors combine to modify the effects of dispersal rate on synchrony and metapopulation dynamics. In a fully factorial experimental design, we investigated the combined effects of (1) dispersal, (2) parasite infection, and (3) synchrony in temperature fluctuations on subpopulation synchrony, metapopulation instability, and minimum population size, in laboratory metapopulations of the ciliate Paramecium caudatum. Metapopulations, comprising two subpopulations linked by high or low levels of dispersal, were exposed to daily fluctuations in temperature between permissive (23 degrees C) and restrictive (5 degrees C) conditions. Infected metapopulations started the experiment with one subpopulation uninfected, while the other was infected at a prevalence of 5% with the bacterial parasite Holospora undulata. The temperature synchrony treatment involved subpopulations within a metapopulation following the same (synchronous temperatures) or different (asynchronous temperatures) temporal sequences. Population size was tracked over the 56-day experiment. We found that subpopulation density fluctuations were synchronized by high dispersal in infected metapopulations, and by synchronous temperatures in all metapopulations. Subpopulation synchrony was positively correlated with metapopulation instability and minimum metapopulation size, highlighting the multiple consequences of our treatments for metapopulation dynamics. Our results illustrate how parasites can generate dispersal-driven synchrony in non-cycling, declining populations. This "biotic forcing" via a natural enemy added to the temperature-dependent environmental forcing. We therefore conclude that predictions of metapopulation persistence in natural populations

  1. Optimal Planning of Sustainable Buildings: Integration of Life Cycle Assessment and Optimization in a Decision Support System (DSS

    Directory of Open Access Journals (Sweden)

    Fabio Magrassi

    2016-06-01

    Full Text Available Energy efficiency measures in buildings can provide for a significant reduction of greenhouse gas (GHG emissions. A sustainable design and planning of technologies for energy production should be based on economic and environmental criteria. Life Cycle Assessment (LCA is used to quantify the environmental impacts over the whole cycle of life of production plants. Optimization models can support decisions that minimize costs and negative impacts. In this work, a multi-objective decision problem is formalized that takes into account LCA calculations and that minimizes costs and GHG emissions for general buildings. A decision support system (DSS is applied to a real case study in the Northern Italy, highlighting the advantage provided by the installation of renewable energy. Moreover, a comparison among different optimal and non optimal solution was carried out to demonstrate the effectiveness of the proposed DSS.

  2. Contingency Contractor Optimization Phase 3 Sustainment Third-Party Software List - Contingency Contractor Optimization Tool - Prototype

    Energy Technology Data Exchange (ETDEWEB)

    Durfee, Justin David; Frazier, Christopher Rawls; Bandlow, Alisa

    2016-05-01

    The Contingency Contractor Optimization Tool - Prototype (CCOT-P) requires several third-party software packages. These are documented below for each of the CCOT-P elements: client, web server, database server, solver, web application and polling application.

  3. Optimal design of sustainable chemical processes via a combined simulation-optimization approach

    OpenAIRE

    Brunet Solé, Robert

    2012-01-01

    The society is every day more conscious about the scarce of resources, the global economy, and the environmental changes. Hence, chemical companies have the necessity to be adapted and develop more sustainable processes. There is a clear demanding to the scientific community to develop systematic tools to achieve reductions in the production costs as well as the associated environmental impact in order to develop decision support tools for the design of chemical plants. This thesis introdu...

  4. Contagion dynamics in time-varying metapopulation networks

    CERN Document Server

    Liu, Suyu; Perra, Nicola

    2012-01-01

    The metapopulation framework is adopted in a wide array of disciplines to describe systems of well separated yet connected subpopulations. The subgroups/patches are often represented as nodes in a network whose links represent the migration routes among them. The connections are usually considered as static, an approximation that is appropriate for the description of many systems, such as cities connected by human mobility, but it is obviously inadequate in those real systems where links evolve in time on a faster timescale. In the case of farmed animals, for example, the connections between each farm/node vary in time according to the different stages of production. Here we address this case by investigating simple contagion processes on temporal metapopulation networks. We focus on the SIR process, and we determine the mobility threshold for the onset of an epidemic spreading in the framework of activity-driven network models. Remarkably, we find profound differences from the case of static networks, determ...

  5. Emergence of metapopulations and echo chambers in mobile agents

    CERN Document Server

    Starnini, Michele; Baronchelli, Andrea

    2016-01-01

    Multi-agent models often describe populations segregated either in the physical space, i.e. subdivided in metapopulations, or in the ecology of opinions, i.e. partitioned in echo chambers. Here we show how the interplay between homophily and social influence controls the emergence of both kinds of segregation in a simple model of mobile agents, endowed with a continuous opinion variable. In the model, physical proximity determines a progressive convergence of opinions but differing opinions result in agents moving away from each others. This feedback between mobility and social dynamics determines to the onset of a stable dynamical metapopulation scenario where physically separated groups of like-minded individuals interact with each other through the exchange of agents. The further introduction of confirmation bias in social interactions, defined as the tendency of an individual to favor opinions that match his own, leads to the emergence of echo chambers where different opinions can coexist also within the ...

  6. Metapopulation epidemic models with heterogeneous mixing and travel behaviour

    CERN Document Server

    Apolloni, Andrea; Ramasco, Jose' J; Jensen, Pablo; Colizza, Vittoria

    2014-01-01

    The complex interplay between population movements in space and non-homogeneous mixing patterns have so far hindered the fundamental understanding of the conditions for spatial invasion through a general theoretical framework. To address this issue, we present an analytical modelling approach taking into account such interplay under general conditions of mobility and interactions, in the simplifying assumption of two population classes. We describe a spatially structured population with non-homogeneous mixing and travel behaviour through a multi-host stochastic epidemic metapopulation model. Different population partitions, mixing patterns and mobility structures are considered, along with a specific application for the study of the role of age partition in the early spread of the 2009 H1N1 pandemic influenza. We provide a complete mathematical formulation of the model and derive a semi-analytical expression of the threshold condition for global invasion of an emerging infectious disease in the metapopulation...

  7. Analysis of the spread of tuberculosis in heterogeneous complex metapopulations

    CERN Document Server

    Tsanou, Berge; Tewa, Jean Jules

    2011-01-01

    his paper describes and analyzes the spatial spread of tuberculosis (TB) on complex metapopulation, that is, networks of populations connected by migratory flows whose configurations are described in terms of connectivity distribution of nodes (patches) and the conditional probabilities of connections among classes of nodes sharing the same degree. The migration and transmission processes occur simultaneously. For uncorrelated networks under the assumption of standard incidence transmission, we compute the disease-free equilibrium and the basic reproduction number, and show that the disease-free equilibrium is locally asymptotically stable. Moreover, for uncorrelated networks and under assumption of simple mass action transmission, we give a necessary and sufficient conditions for the instability of the disease-free equilibrium. The existence of endemic equilibria is also discussed. Finally, the prevalence of the TB infection across the metapopulation as a function of the path connectivity is studied using nu...

  8. Population proteomics: an emerging discipline to study metapopulation ecology.

    Science.gov (United States)

    Biron, David G; Loxdale, Hugh D; Ponton, Fleur; Moura, Hercules; Marché, Laurent; Brugidou, Christophe; Thomas, Frédéric

    2006-03-01

    Proteomics research has developed until recently in a relative isolation from other fast-moving disciplines such as ecology and evolution. This is unfortunate since applying proteomics to these disciplines has apparently the potential to open new perspectives. The huge majority of species indeed exhibit over their entire geographic range a metapopulation structure, occupying habitats that are fragmented and heterogeneous in space and/or through time. Traditionally, population genetics is the main tool used to studying metatopulations, as it describes the spatial structure of populations and the level of gene flow between them. In this Viewpoint, we present the reasons why we think that proteomics, because of the level of integration it promotes, has the potential to resolve interesting issues specific to metapopulation biology and adaptive processes.

  9. Design for Sustainability of Industrial Symbiosis based on Emergy and Multi-objective Particle Swarm Optimization

    DEFF Research Database (Denmark)

    Ren, Jingzheng; Liang, Hanwei; Dong, Liang

    2016-01-01

    Industrial symbiosis provides novel and practical pathway to the design for the sustainability. Decision support tool for its verification is necessary for practitioners and policy makers, while to date, quantitative research is limited. The objective of this work is to present an innovative...... approach for supporting decision-making in the design for the sustainability with the implementation of industrial symbiosis in chemical complex. Through incorporating the emergy theory, the model is formulated as a multi-objective approach that can optimize both the economic benefit and sustainable...... performance of the integrated industrial system. A set of emergy based evaluation index are designed. Multi-objective Particle Swarm Algorithm is proposed to solve the model, and the decision-makers are allowed to choose the suitable solutions form the Pareto solutions. An illustrative case has been studied...

  10. Process optimization on ambitious sustainability goals through the framework of DGNB

    DEFF Research Database (Denmark)

    Espenhein, Kasper; Jensen, Lotte Bjerregaard

    2017-01-01

    The need for designing buildings with a sustainable approach is higher than ever before, but using building sustainability assessment tools, such as DGNB, is a comprehensive and complex activity. This has led to attempts to optimize the tangibility for usage of sustainability assessment tools...... the use of Grounded Theory. The findings expose that the project brief must define a healthy framework for both collaboration and projectmanagement, and a specific two-step approach to obtain the certification goal should be performed. The size of the criteria determined how it should be addressed...... in the project. DGNB was also found to have an impact on the architectural quality leading to certain architectural traits. An important finding was that it is paramount that all stakeholders take an integrated holistic approach when applying DGNB....

  11. Metapopulation Structure and Dynamics of an Endangered Butterfly

    Science.gov (United States)

    2010-01-01

    the number of eggs laid in the site by adults for the entire generation. If sex ratio and daily per capita fecundity were similar across gen- erations...Metapopulation theory has been remarkably instructive for understanding and managing rare or endangered species including amphibians (Marsh & Trenham 2001), birds...ics and amphibian conservation. Conservation Biology, 15(1), 40–49. Manly, B. F. J. (1976). Extensions to Kiritani and Nakasuji’s method for analysing

  12. Optimization and Simulation of Collaborative Networks for Sustainable Production and Transportation

    DEFF Research Database (Denmark)

    Liotta, Giacomo; Kaihara, Toshiya; Stecca, Giuseppe

    2016-01-01

    Complex and delocalized manufacturing industries require high levels of integration between production and transportation in order to effectively implement lean and agile operations. There are, however, limitations in research and applications simultaneously embodying further sustainability...... dimensions. This paper presents a methodological framework based on optimization and simulation to integrate aggregate optimized plans for production and multimodal transportation with detailed dynamic distribution plans affected by demand uncertainty. The objective function of the optimization model...... considers supply, production, transportation, and CO2 emission costs, as well as collaboration over the multimodal network. Bill-of-materials and capacity constraints are included. A feedback between simulation and optimization is used to plan requirements for materials and components. Computational...

  13. Empirical determinants of measles metapopulation dynamics in England and Wales.

    Science.gov (United States)

    Finkenstädt, B; Grenfell, B

    1998-02-07

    A key issue in metapopulation dynamics is the relative impact of internal patch dynamics and coupling between patches. This problem can be addressed by analysing large spatiotemporal data sets, recording the local and global dynamics of metapopulations. In this paper, we analyse the dynamics of measles meta-populations in a large spatiotemporal case notification data set, collected during the pre-vaccination era in England and Wales. Specifically, we use generalized linear statistical models to quantify the relative importance of local influences (birth rate and population size) and regional coupling on local epidemic dynamics. Apart from the proportional effect of local population size on case totals, the models indicate patterns of local and regional dynamic influences which depend on the current state of epidemics. Birth rate and geographic coupling are not associated with the size of major epidemics. By contrast, minor epidemics--and especially the incidence of local extinction of infection--are influenced both by birth rate and geographical coupling. Birth rate at a lag of four years provides the best fit, reflecting the delayed recruitment of susceptibles to school cohorts. A hierarchical index of spatial coupling to large centres provides the best spatial model. The model also indicates that minor epidemics and extinction patterns are more strongly influenced by this regional effect than the local impact of birth rate.

  14. Contingency Contractor Optimization Phase 3 Sustainment Database Design Document - Contingency Contractor Optimization Tool - Prototype

    Energy Technology Data Exchange (ETDEWEB)

    Frazier, Christopher Rawls; Durfee, Justin David; Bandlow, Alisa; Gearhart, Jared Lee; Jones, Katherine A

    2016-05-01

    The Contingency Contractor Optimization Tool – Prototype (CCOT-P) database is used to store input and output data for the linear program model described in [1]. The database allows queries to retrieve this data and updating and inserting new input data.

  15. Optimizing cutting conditions on sustainable machining of aluminum alloy to minimize power consumption

    Science.gov (United States)

    Nur, Rusdi; Suyuti, Muhammad Arsyad; Susanto, Tri Agus

    2017-06-01

    Aluminum is widely utilized in the industrial sector. There are several advantages of aluminum, i.e. good flexibility and formability, high corrosion resistance and electrical conductivity, and high heat. Despite of these characteristics, however, pure aluminum is rarely used because of its lacks of strength. Thus, most of the aluminum used in the industrial sectors was in the form of alloy form. Sustainable machining can be considered to link with the transformation of input materials and energy/power demand into finished goods. Machining processes are responsible for environmental effects accepting to their power consumption. The cutting conditions have been optimized to minimize the cutting power, which is the power consumed for cutting. This paper presents an experimental study of sustainable machining of Al-11%Si base alloy that was operated without any cooling system to assess the capacity in reducing power consumption. The cutting force was measured and the cutting power was calculated. Both of cutting force and cutting power were analyzed and modeled by using the central composite design (CCD). The result of this study indicated that the cutting speed has an effect on machining performance and that optimum cutting conditions have to be determined, while sustainable machining can be followed in terms of minimizing power consumption and cutting force. The model developed from this study can be used for evaluation process and optimization to determine optimal cutting conditions for the performance of the whole process.

  16. Nanosized sustained-release pyridostigmine bromide microcapsules: process optimization and evaluation of characteristics

    Directory of Open Access Journals (Sweden)

    Tan Q

    2013-02-01

    Full Text Available Qunyou Tan,1,* Rong Jiang,3,* Meiling Xu,2,4,* Guodong Liu,5,* Songlin Li,1 Jingqing Zhang21Department of Thoracic Surgery, Institute of Surgery Research, Daping Hospital, Third Military Medical University, 2Medicine Engineering Research Center, Chongqing Medical University, 3Stem Cells and Tissue Engineering Research, Chongqing Medical University, 4Department of Pharmacy, Chongqing Emergency Medical Center, 5Eighth Department, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Chongqing, People’s Republic of China*These authors contributed equally to this workBackground: Pyridostigmine bromide (3-[[(dimethylamino-carbonyl]oxy]-1-methylpyridinium bromide, a reversible inhibitor of cholinesterase, is given orally in tablet form, and a treatment schedule of multiple daily doses is recommended for adult patients. Nanotechnology was used in this study to develop an alternative sustained-release delivery system for pyridostigmine, a synthetic drug with high solubility and poor oral bioavailability, hence a Class III drug according to the Biopharmaceutics Classification System. Novel nanosized pyridostigmine-poly(lactic acid microcapsules (PPNMCs were expected to have a longer duration of action than free pyridostigmine and previously reported sustained-release formulations of pyridostigmine.Methods: The PPNMCs were prepared using a double emulsion-solvent evaporation method to achieve sustained-release characteristics for pyridostigmine. The preparation process for the PPNMCs was optimized by single-factor experiments. The size distribution, zeta potential, and sustained-release behavior were evaluated in different types of release medium.Results: The optimal volume ratio of inner phase to external phase, poly(lactic acid concentration, polyvinyl alcohol concentration, and amount of pyridostigmine were 1:10, 6%, 3% and 40 mg, respectively. The negatively charged PPNMCs had an average particle size of 937.9 nm

  17. A spatial multi-objective optimization model for sustainable urban wastewater system layout planning.

    Science.gov (United States)

    Dong, X; Zeng, S; Chen, J

    2012-01-01

    Design of a sustainable city has changed the traditional centralized urban wastewater system towards a decentralized or clustering one. Note that there is considerable spatial variability of the factors that affect urban drainage performance including urban catchment characteristics. The potential options are numerous for planning the layout of an urban wastewater system, which are associated with different costs and local environmental impacts. There is thus a need to develop an approach to find the optimal spatial layout for collecting, treating, reusing and discharging the municipal wastewater of a city. In this study, a spatial multi-objective optimization model, called Urban wastewateR system Layout model (URL), was developed. It is solved by a genetic algorithm embedding Monte Carlo sampling and a series of graph algorithms. This model was illustrated by a case study in a newly developing urban area in Beijing, China. Five optimized system layouts were recommended to the local municipality for further detailed design.

  18. Techno-Economic Optimization of a Sustainable Energy System for a 100% Renewables Smart House

    DEFF Research Database (Denmark)

    Craciun, Vasile Simion; Blarke, Morten; Trifa, Viorel

    2012-01-01

    , and hot tap water demand, balancing fluctuating wind power and both solar power and solar thermal supply utilizing advanced heat pump and both electro-chemical electricity storage, and hot and cold thermal storages. Our research is basically concerned with the question of how to design 100 % renewable...... for a sustainable energy system for a 100% renewables based Smart House (SH). We have devised and analysed an innovative high-efficiency approach to residential energy supply. The analysis involves detailed technical specifications and considerations for providing optimal supply of electricity, heating, cooling...... technical and economic challenges. One such challenge is the discontinuity, or intermittency, of generation, as most renewable energy resources depend on the climate, which is why their use requires complex design, planning and control optimization strategies. This paper presents a model and optimization...

  19. Design for sustainability of industrial symbiosis based on emergy and multi-objective particle swarm optimization.

    Science.gov (United States)

    Ren, Jingzheng; Liang, Hanwei; Dong, Liang; Sun, Lu; Gao, Zhiqiu

    2016-08-15

    Industrial symbiosis provides novel and practical pathway to the design for the sustainability. Decision support tool for its verification is necessary for practitioners and policy makers, while to date, quantitative research is limited. The objective of this work is to present an innovative approach for supporting decision-making in the design for the sustainability with the implementation of industrial symbiosis in chemical complex. Through incorporating the emergy theory, the model is formulated as a multi-objective approach that can optimize both the economic benefit and sustainable performance of the integrated industrial system. A set of emergy based evaluation index are designed. Multi-objective Particle Swarm Algorithm is proposed to solve the model, and the decision-makers are allowed to choose the suitable solutions form the Pareto solutions. An illustrative case has been studied by the proposed method, a few of compromises between high profitability and high sustainability can be obtained for the decision-makers/stakeholders to make decision. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Multi-Objective Spatial Optimization: Sustainable Land Use Allocation at Sub-Regional Scale

    Directory of Open Access Journals (Sweden)

    Guadalupe Azuara García

    2017-06-01

    Full Text Available The rational use of territorial resources is a key factor in achieving sustainability. Spatial planning is an important tool that helps decision makers to achieve sustainability in the long term. This work proposes a multi-objective model for sustainable land use allocation known as MAUSS (Spanish acronym for “Modelo de Asignación de Uso Sostenible de Suelo” The model was applied to the Plains of San Juan, Puebla, Mexico, which is currently undergoing a rapid industrialization process. The main objective of the model is to generate land use allocations that lead to a territorial balance within regions in three main ways by maximizing income, minimizing negative environmental pressure on water and air through specific evaluations of water use and CO2 emissions, and minimizing food deficit. The non-sorting genetic algorithm II (NSGA-II is the evolutionary optimization algorithm of MAUSS. NSGA-II has been widely modified through a novel and efficient random initializing operator that enables spatial rationale from the initial solutions, a crossover operator designed to streamline the best genetic information transmission as well as diversity, and two geometric operators, geographic dispersion (GDO and the proportion (PO, which strengthen spatial rationality. MAUSS provided a more sustainable land use allocation compared to the current land use distribution in terms of higher income, 9% lower global negative pressure on the environment and 5.2% lower food deficit simultaneously.

  1. Spatial occupancy models for predicting metapopulation dynamics and viability following reintroduction

    Science.gov (United States)

    Chandler, Richard B.; Muths, Erin L.; Sigafus, Brent H.; Schwalbe, Cecil R.; Jarchow, Christopher J; Hossack, Blake R.

    2015-01-01

    The reintroduction of a species into its historic range is a critical component of conservation programmes designed to restore extirpated metapopulations. However, many reintroduction efforts fail, and the lack of rigorous monitoring programmes and statistical models have prevented a general understanding of the factors affecting metapopulation viability following reintroduction.

  2. Difference in metapopulation structure and dynamics of two species of coexistent melitaeine butterflies

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    According to investigation on two species of melitaeine butterflies in Yanjiaping Village, Chicheng County, Hebei Province, China, between 1998-2002, together with the use of 1:10000 contour map of the local area, some conclusions are shown by the SPSS and GIS analysis of data obained from GPS: (1) The two species of melitaeine butterflies have different metapopulation structures. M. phoebe is a source-sink metapopulation, while E. aurinia is a classical metapopulation, supporting the analytic result from our former genetic research. (2) The two species of melitaeine butterflies exhibit different trends of population dynamics. M. phoebe source-sink metapopulation is very unsteady, and is always small, thus has a tendency to go extinct gradually. But E. aurinia classical metapopulation is stable, and has maintained a larger population size. Therefore, it stands a better chance of long-term survival. (3) The two species of melitaeine butterflies are significantly related in both patch occupancy and local population size. (4) The effect of isolation is significant on the metapopulations of these two species of melitaeine butterflies, consistent with the classical theories, whereas the effect of patch area is not significant on the metapopulations of these two species of melitaeine butterflies, which is inconsistent with the classical theories. Therefore, other factors, such as habitat quality, should be considered for their influences on metapopulations.

  3. An Integrated Modeling Approach to Evaluate and Optimize Data Center Sustainability, Dependability and Cost

    Directory of Open Access Journals (Sweden)

    Gustavo Callou

    2014-01-01

    Full Text Available Data centers have evolved dramatically in recent years, due to the advent of social networking services, e-commerce and cloud computing. The conflicting requirements are the high availability levels demanded against the low sustainability impact and cost values. The approaches that evaluate and optimize these requirements are essential to support designers of data center architectures. Our work aims to propose an integrated approach to estimate and optimize these issues with the support of the developed environment, Mercury. Mercury is a tool for dependability, performance and energy flow evaluation. The tool supports reliability block diagrams (RBD, stochastic Petri nets (SPNs, continuous-time Markov chains (CTMC and energy flow (EFM models. The EFM verifies the energy flow on data center architectures, taking into account the energy efficiency and power capacity that each device can provide (assuming power systems or extract (considering cooling components. The EFM also estimates the sustainability impact and cost issues of data center architectures. Additionally, a methodology is also considered to support the modeling, evaluation and optimization processes. Two case studies are presented to illustrate the adopted methodology on data center power systems.

  4. Resource allocation for epidemic control in metapopulations.

    Directory of Open Access Journals (Sweden)

    Martial L Ndeffo Mbah

    Full Text Available Deployment of limited resources is an issue of major importance for decision-making in crisis events. This is especially true for large-scale outbreaks of infectious diseases. Little is known when it comes to identifying the most efficient way of deploying scarce resources for control when disease outbreaks occur in different but interconnected regions. The policy maker is frequently faced with the challenge of optimizing efficiency (e.g. minimizing the burden of infection while accounting for social equity (e.g. equal opportunity for infected individuals to access treatment. For a large range of diseases described by a simple SIRS model, we consider strategies that should be used to minimize the discounted number of infected individuals during the course of an epidemic. We show that when faced with the dilemma of choosing between socially equitable and purely efficient strategies, the choice of the control strategy should be informed by key measurable epidemiological factors such as the basic reproductive number and the efficiency of the treatment measure. Our model provides new insights for policy makers in the optimal deployment of limited resources for control in the event of epidemic outbreaks at the landscape scale.

  5. Connectivity, cycles, and persistence thresholds in metapopulation networks.

    Science.gov (United States)

    Artzy-Randrup, Yael; Stone, Lewi

    2010-08-05

    Synthesising the relationships between complexity, connectivity, and the stability of large biological systems has been a longstanding fundamental quest in theoretical biology and ecology. With the many exciting developments in modern network theory, interest in these issues has recently come to the forefront in a range of multidisciplinary areas. Here we outline a new theoretical analysis specifically relevant for the study of ecological metapopulations focusing primarily on marine systems, where subpopulations are generally connected via larval dispersal. Our work determines the qualitative and quantitative conditions by which dispersal and network structure control the persistence of a set of age-structured patch populations. Mathematical modelling combined with a graph theoretic analysis demonstrates that persistence depends crucially on the topology of cycles in the dispersal network which tend to enhance the effect of larvae "returning home." Our method clarifies the impact directly due to network structure, but this almost by definition can only be achieved by examining the simplified case in which patches are identical; an assumption that we later relax. The methodology identifies critical migration routes, whose presence are vital to overall stability, and therefore should have high conservation priority. In contrast, "lonely links," or links in the network that do not participate in a cyclical component, have no impact on persistence and thus have low conservation priority. A number of other intriguing criteria for persistence are derived. Our modelling framework reveals new insights regarding the determinants of persistence, stability, and thresholds in complex metapopulations. In particular, while theoretical arguments have, in the past, suggested that increasing connectivity is a destabilizing feature in complex systems, this is not evident in metapopulation networks where connectivity, cycles, coherency, and heterogeneity all tend to enhance

  6. Connectivity, cycles, and persistence thresholds in metapopulation networks.

    Directory of Open Access Journals (Sweden)

    Yael Artzy-Randrup

    Full Text Available Synthesising the relationships between complexity, connectivity, and the stability of large biological systems has been a longstanding fundamental quest in theoretical biology and ecology. With the many exciting developments in modern network theory, interest in these issues has recently come to the forefront in a range of multidisciplinary areas. Here we outline a new theoretical analysis specifically relevant for the study of ecological metapopulations focusing primarily on marine systems, where subpopulations are generally connected via larval dispersal. Our work determines the qualitative and quantitative conditions by which dispersal and network structure control the persistence of a set of age-structured patch populations. Mathematical modelling combined with a graph theoretic analysis demonstrates that persistence depends crucially on the topology of cycles in the dispersal network which tend to enhance the effect of larvae "returning home." Our method clarifies the impact directly due to network structure, but this almost by definition can only be achieved by examining the simplified case in which patches are identical; an assumption that we later relax. The methodology identifies critical migration routes, whose presence are vital to overall stability, and therefore should have high conservation priority. In contrast, "lonely links," or links in the network that do not participate in a cyclical component, have no impact on persistence and thus have low conservation priority. A number of other intriguing criteria for persistence are derived. Our modelling framework reveals new insights regarding the determinants of persistence, stability, and thresholds in complex metapopulations. In particular, while theoretical arguments have, in the past, suggested that increasing connectivity is a destabilizing feature in complex systems, this is not evident in metapopulation networks where connectivity, cycles, coherency, and heterogeneity all tend

  7. Optimizing root system architecture in biofuel crops for sustainable energy production and soil carbon sequestration.

    Science.gov (United States)

    To, Jennifer Pc; Zhu, Jinming; Benfey, Philip N; Elich, Tedd

    2010-09-08

    Root system architecture (RSA) describes the dynamic spatial configuration of different types and ages of roots in a plant, which allows adaptation to different environments. Modifications in RSA enhance agronomic traits in crops and have been implicated in soil organic carbon content. Together, these fundamental properties of RSA contribute to the net carbon balance and overall sustainability of biofuels. In this article, we will review recent data supporting carbon sequestration by biofuel crops, highlight current progress in studying RSA, and discuss future opportunities for optimizing RSA for biofuel production and soil carbon sequestration.

  8. Motion-induced synchronization in metapopulations of mobile agents

    CERN Document Server

    Gómez-Gardeñes, Jesús; Sinatra, Roberta; Latora, Vito

    2012-01-01

    We study the influence of motion on the emergence of synchronization in a metapopulation of random walkers moving on a heterogeneous network and subject to Kuramoto interactions at the network nodes. We discover a novel mechanism of transition to macroscopic dynamical order induced by the walkers' motion. Furthermore, we observe two different microscopic paths to synchronization: depending on the rules of the motion, either low-degree nodes or the hubs drive the whole system towards synchronization. We provide analytical arguments to understand these results.

  9. Metapopulation dynamics enable persistence of influenza A, including A/H5N1, in poultry.

    Directory of Open Access Journals (Sweden)

    Parviez Rana Hosseini

    Full Text Available Highly pathogenic influenza A/H5N1 has persistently but sporadically caused human illness and death since 1997. Yet it is still unclear how this pathogen is able to persist globally. While wild birds seem to be a genetic reservoir for influenza A, they do not seem to be the main source of human illness. Here, we highlight the role that domestic poultry may play in maintaining A/H5N1 globally, using theoretical models of spatial population structure in poultry populations. We find that a metapopulation of moderately sized poultry flocks can sustain the pathogen in a finite poultry population for over two years. Our results suggest that it is possible that moderately intensive backyard farms could sustain the pathogen indefinitely in real systems. This fits a pattern that has been observed from many empirical systems. Rather than just employing standard culling procedures to control the disease, our model suggests ways that poultry production systems may be modified.

  10. USAF Logistics Process Optimization Study for the Aircraft Asset Sustainment Process. Volume 3. Future to be Asset Sustainment Process Model.

    Science.gov (United States)

    2007-11-02

    Models), contains the To-Be Retail Asset Sustainment Process Model displaying the activities and functions related to the improved processes for receipt...of a logistics process model for a more distant future asset sustainment scenario unconstrained by today’s logistics information systems limitations...It also contains a process model reflecting the Reengineering Team’s vision of the future asset sustainment process.

  11. Sustained Release Floating Microspheres Of Acyclovir: Formulation, Optimization, Characterization And In Vitro Evaluation

    Directory of Open Access Journals (Sweden)

    Parmar Kunal Vinodbhai

    2011-03-01

    Full Text Available The aim of the present work was to prepare floating microspheres of acyclovir to prolong residence time in stomach and to sustain the release of acyclovir. Acyclovir loaded floating microspheres were prepared by double emulsion solvent evaporation method. The 32 full factorial design was applied to optimize the formulation. The resultant microspheres were evaluated for average particle size, percentage encapsulation efficiency, in vitro drug release and model fitting kinetics. Scanning electron microscopy, Fourier transform infrared (FTIR spectroscopy and differential scanning calorimetry were used to investigate the physical state of the drug in the microspheres. The particle size of microspheres was in the range of 275-340 µm. Percentage encapsulation efficiency was between 59%-77% w/w. Microspheres remained buoyant for more than about 12 h. The results of FT-IR spectroscopy and differential scanning calorimetry indicated the stable character of acyclovir in microspheres and also revealed absence of drugpolymer interaction. The in vitro drug release study showed that acyclovir release from the microspheres was slow and sustained for more than about 10 h. Drug release followed Korsemeyer-peppas model. The results of factorial batches revealed that the concentration of ethyl cellulose and stirring speed significantly affected drug encapsulation efficiency and particle size of the microspheres. Thus we can conclude that floating microspheres can successfully be developed to sustain the drug release.

  12. Distributed optimal technology networks: a concept and strategy for potable water sustainability.

    Science.gov (United States)

    Weber, W J

    2002-01-01

    Viable strategies for ensuring adequate supplies of potable water are essential to long-term societal sustainability. The steadily increasing necessity for multiple reuse of water in urban societies is even now taxing our technical and financial abilities to meet ongoing needs for water suitable for human consumption. As a consequence, the current practice of treating the entire water demands of urban communities to the increasingly stringent standards required for drinking water is becoming an unsustainable practice, and thus a questionable strategy for planning and development of urban water systems. An innovative technology-based concept for implementation of a more sustainable strategy and practice for potable water is developed here. The concept is predicated on the inherent advantages of flexibility and responsiveness associated with decentralization of complex functions and operations. Specifically, it calls for strategic dispersal of flexible advanced treatment and control technologies throughout urban water transport and storage networks. This is in direct contradistinction to current strategies and practices of centralized and inflexible monolithic facilities. By integrating use-related satellite systems with critical components of existing systems and infrastructures, the concept can enable and facilitate optimal cost-effective applications of highly sophisticated advanced treatment and on-line monitoring and control technologies to in-place infrastructures in a holistic and sustainable manner.

  13. Linking energy policy, electricity generation and transmission using strong sustainability and co-optimization

    Energy Technology Data Exchange (ETDEWEB)

    Bishop, Justin D.K.; Amaratunga, Gehan A.J. [University of Cambridge, Department of Engineering, 9 JJ Thomson Ave, Cambridge CB3 0FA (United Kingdom); Rodriguez, Cuauhtemoc [Cambridge Consultants (United Kingdom)

    2010-06-15

    The design of a sustainable electricity generation and transmission system is based on the established science of anthropogenic climate change and the realization that depending on imported fossil-fuels is becoming a measure of energy insecurity of supply. A model is proposed which integrates generation fuel mix composition, assignment of plants and optimized power flow, using Portugal as a case study. The result of this co-optimized approach is an overall set of generator types/fuels which increases the diversity of Portuguese electricity supply, lowers its dependency on imported fuels by 21.30% and moves the country towards meeting its regional and international obligations of 31% energy from renewables by 2020 and a 27% reduction in greenhouse gas emissions by 2012, respectively. The quantity and composition of power generation at each bus is specified, with particular focus on quantifying the amount of distributed generation. Based on other works, the resultant, overall distributed capacity penetration of 11.88% of total installed generation is expected to yield positive network benefits. Thus, the model demonstrates that national energy policy and technical deployment can be linked through sustainability and, moreover, that the respective goals may be mutually achieved via holistic, integrated design. (author)

  14. Formulation and optimization of sustained release tablets of venlafaxine resinates using response surface methodology

    Directory of Open Access Journals (Sweden)

    Madgulkar Ashwini

    2009-01-01

    Full Text Available The aim of the current study was to design sustained release matrix tablets of venlafaxine hydrochloride using ion exchange resin with the incorporation of hydrophilic and hydrophobic polymer combinations. Venlafaxine HCl was loaded onto Indion 244 by batch method and then resinate were wet granulated with ethyl cellulose and blended with hydroxypropylmethylcellulose and compressed. A central composite design for 2 factors at 3 levels each was employed to systematically optimize drug release profile at 2 h and at 18 h. Hydroxypropylmethylcellulose and ethylcellulose were taken as the independent variables. Response surface plots and contour plots were drawn, and optimum formulations were selected by feasibility and grid searches. Resinate shows inadequate sustained release profile. Compressed matrices exhibited the anomalous release mechanism, as the value of release rate exponent (n varied between 08109 and 08719, resulting in regulated and complete release until 20 h. Validation of optimization study, performed using five confirmatory runs, indicated very high degree of prognostic ability of response surface methodology, with mean percentage error as 1.152±1.88%. Regulated drug release study indicates that the hydrophilic and hydrophobic matrix tablets of venlafaxine resinate prepared using hydroxypropylmethylcellulose and ethylcellulose, can successfully be employed as a once-a-day oral controlled release drug delivery system.

  15. Optimized loading and sustained release of hydrophilic proteins from internally nanostructured particles.

    Science.gov (United States)

    Chemelli, Angela; Maurer, Manuela; Geier, Roman; Glatter, Otto

    2012-12-11

    In this study, we demonstrate that emulsified microemulsions and micellar cubosomes are suitable as sustained delivery vehicles for water-soluble proteins. Through structural modifications, the loading efficiency of two model proteins, namely bovine serum albumin (BSA) and cytochrome c could be remarkably increased. A procedure for preparing these particles loaded with optimized amounts of sensitive substances is presented. Loading and dispersion at low temperatures is performed in two successive steps. First, a water-in-oil microemulsion is loaded with the proteins. Subsequently, this phase is dispersed in water resulting in particles with microemulsion and micellar cubic internal structure and a size of approximately 620 nm. This two-step method ensures optimal loading of the particles with the proteins. These nanostructured particles are able to sustain the release of the water-soluble BSA and cytochrome c. Within one day, less than 10% of BSA and 15% of cytochrome c are released. The release rate of cytochrome c is influenced by the nanostructure of the particles.

  16. Emergence of metapopulations and echo chambers in mobile agents

    Science.gov (United States)

    Starnini, Michele; Frasca, Mattia; Baronchelli, Andrea

    2016-08-01

    Multi-agent models often describe populations segregated either in the physical space, i.e. subdivided in metapopulations, or in the ecology of opinions, i.e. partitioned in echo chambers. Here we show how both kinds of segregation can emerge from the interplay between homophily and social influence in a simple model of mobile agents endowed with a continuous opinion variable. In the model, physical proximity determines a progressive convergence of opinions but differing opinions result in agents moving away from each others. This feedback between mobility and social dynamics determines the onset of a stable dynamical metapopulation scenario where physically separated groups of like-minded individuals interact with each other through the exchange of agents. The further introduction of confirmation bias in social interactions, defined as the tendency of an individual to favor opinions that match his own, leads to the emergence of echo chambers where different opinions coexist also within the same group. We believe that the model may be of interest to researchers investigating the origin of segregation in the offline and online world.

  17. Contagion dynamics in time-varying metapopulation networks

    Science.gov (United States)

    Perra, Nicola; Liu, Suyu; Baronchelli, Andrea

    2014-03-01

    The metapopulation framework is adopted in a wide array of disciplines to describe systems of well separated yet connected subpopulations. The subgroups/patches are often represented as nodes in a network whose links represent the migration routes among them. The connections has been so far mostly considered as static, but in general evolve in time. Here we address this case by investigating simple contagion processes on time-varying metapopulation networks. We focus on the SIR process, and determine analytically the mobility threshold for the onset of an epidemic spreading in the framework of activity-driven network models. We find profound differences from the case of static networks. The threshold is entirely described by the dynamical parameters defining the average number of instantaneously migrating individuals, and does not depend on the properties of the static network representation. Remarkably, the diffusion and contagion processes are slower in time-varying graphs than in their aggregated static counterparts, the mobility threshold been even two orders of magnitude larger in the first case. The presented results confirm the importance of considering the time-varying nature of complex networks.

  18. Determining a sustainable and economically optimal wastewater treatment and discharge strategy.

    Science.gov (United States)

    Hardisty, Paul E; Sivapalan, Mayuran; Humphries, Robert

    2013-01-15

    Options for treatment and discharge of wastewater in regional Western Australia (WA) are examined from the perspective of overall sustainability and social net benefit. Current practice in the state has typically involved a basic standard of treatment deemed to be protective of human health, followed by discharge to surface water bodies. Community and regulatory pressure to move to higher standards of treatment is based on the presumption that a higher standard of treatment is more protective of the environment and society, and thus is more sustainable. This analysis tests that hypothesis for Western Australian conditions. The merits of various wastewater treatment and discharge strategies are examined by quantifying financial costs (capital and operations), and by monetising the wider environmental and social costs and benefits of each option over an expanded planning horizon (30 years). Six technical treatment-disposal options were assessed at a test site, all of which met the fundamental criterion of protecting human health. From a financial perspective, the current business-as-usual option is preferred - it is the least cost solution. However, valuing externalities such as water, greenhouse gases, ecological impacts and community amenity, the status quo is revealed as sub-optimal. Advanced secondary treatment with stream disposal improves water quality and provides overall net benefit to society. All of the other options were net present value (NPV) negative. Sensitivity analysis shows that the favoured option outperforms all of the others under a wide range of financial and externality values and assumptions. Expanding the findings across the state reveals that moving from the identified socially optimal level of treatment to higher (tertiary) levels of treatment would result in a net loss to society equivalent to several hundred million dollars. In other words, everyone benefits from improving treatment to the optimum point. But society, the environment, and

  19. Linking extinction-colonization dynamics to genetic structure in a salamander metapopulation.

    Science.gov (United States)

    Cosentino, Bradley J; Phillips, Christopher A; Schooley, Robert L; Lowe, Winsor H; Douglas, Marlis R

    2012-04-22

    Theory predicts that founder effects have a primary role in determining metapopulation genetic structure. However, ecological factors that affect extinction-colonization dynamics may also create spatial variation in the strength of genetic drift and migration. We tested the hypothesis that ecological factors underlying extinction-colonization dynamics influenced the genetic structure of a tiger salamander (Ambystoma tigrinum) metapopulation. We used empirical data on metapopulation dynamics to make a priori predictions about the effects of population age and ecological factors on genetic diversity and divergence among 41 populations. Metapopulation dynamics of A. tigrinum depended on wetland area, connectivity and presence of predatory fish. We found that newly colonized populations were more genetically differentiated than established populations, suggesting that founder effects influenced genetic structure. However, ecological drivers of metapopulation dynamics were more important than age in predicting genetic structure. Consistent with demographic predictions from metapopulation theory, genetic diversity and divergence depended on wetland area and connectivity. Divergence was greatest in small, isolated wetlands where genetic diversity was low. Our results show that ecological factors underlying metapopulation dynamics can be key determinants of spatial genetic structure, and that habitat area and isolation may mediate the contributions of drift and migration to divergence and evolution in local populations.

  20. Forced sustained swimming exercise at optimal speed enhances growth of juvenile yellowtail kingfish (Seriola lalandi

    Directory of Open Access Journals (Sweden)

    Arjan P. Palstra

    2015-01-01

    Full Text Available Swimming exercise at optimal speed may optimize growth performance of yellowtail kingfish in a recirculating aquaculture system. Therefore, optimal swimming speeds (Uopt in m s-1 or body lengths s-1, BL s-1 were assessed and then applied to determine the effects of long-term forced and sustained swimming at Uopt on growth performance of juvenile yellowtail kingfish. Uopt was quantified in Blazka-type swim-tunnels for 145 mm, 206 mm and 311 mm juveniles resulting in values of: 1 0.70 m s-1 or 4.83 BL s-1, 2 0.82 m s-1 or 3.25 BL s-1 and 3 0.85 m s-1 or 2.73 BL s-1. Combined with literature data from larger fish, a relation of Uopt (BL s-1 = 234.07(BL-0.779 (R2= 0.9909 was established for this species. Yellowtail kingfish, either forced to perform sustained swimming exercise at an optimal speed of 2.46 BL s-1 (‘swimmers’ or allowed to perform spontaneous activity at low water flow (‘resters’ in a newly designed 3,600 L oval flume (with flow created by an impeller driven by an electric motor, were then compared. At the start of the experiment, ten fish were sampled representing the initial condition. After 18 days, swimmers (n= 23 showed a 92% greater increase in BL and 46% greater increase in BW as compared to resters (n= 23. As both groups were fed equal rations, feed conversion ratio (FCR for swimmers was 1.21 vs. 1.74 for resters. Doppler ultrasound imaging showed a statistically significant higher blood flow (31% in the ventral aorta of swimmers vs. resters (44 ± 3 mL min-1 vs. 34 ± 3 mL min-1, respectively, under anesthesia. Thus growth performance can be rapidly improved by optimal swimming, without larger feed investments.

  1. Seeking sustainability: multiobjective evolutionary optimization for urban wastewater reuse in China.

    Science.gov (United States)

    Zhang, Wenlong; Wang, Chao; Li, Yi; Wang, Peifang; Wang, Qing; Wang, Dawei

    2014-01-21

    Sustainable design and implementation of wastewater reuse in China have to achieve an optimum compromise among water resources augmenting, pollutants reduction and economic profit. A systematic framework with a multiobjective optimization model is first developed considering the trade-offs among wastewater reuse supplies and demands, costs and profits, as well as pollutants reduction. Pareto fronts of wastewater reuse optimization for 31 provinces of China are obtained through nondominated sorting genetic algorithm trials. The control strategies for each province are selected on the basis of regional water resources and water environment status. On the national level, the control strategies of wastewater reuse scale, BOD5 reduction, and economic profit are 15.39 billion cubic meters, 176.31 kilotons, and 9.68 billion RMB Yuan, respectively. The driving forces of water resources augmenting and water pollution control play more important roles than economic profit during wastewater reuse expanding in China. According to the optimal allocations, reclaimed wastewater should be intensively used in municipal, domestic, and recreative sectors in the regions suffering from quantity-related water scarcity, while it should be focused on industrial users in the regions suffering from quality-related water scarcity. The results present a general picture of wastewater reuse for policy makers in China.

  2. Optimization of urban spatial development against flooding and other climate risks, and wider sustainability objectives

    Directory of Open Access Journals (Sweden)

    Caparros-Midwood Daniel

    2016-01-01

    Full Text Available A spatial optimization framework has been developed to help urban areas mitigate climate risks such as flooding and to curb resource use and greenhouse gas emissions. Measures required to address these issues often conflict with each other, for example more compact cities typically use less energy for transportation but increase runoff from high intensity rainfall events. Balancing potential trade-offs and maximizing synergies between these risks and vulnerabilities is therefore a multi-dimensional, spatial, challenge for urban planners. A spatial optimization framework is used to optimize the following objectives to minimize: (1 risk from heat waves; (2 risk from flooding; (3 the distance of new development to the current central business district; (4 urban sprawl to prevent increased travel costs; and (5 the development of green-space. The framework is applied to a real case study in the North East of England. From an initial configuration, alternative spatial configurations are tested against these objectives and the spatial pattern is evolved over successive generations to search for spatially optimum configurations. The resulting solutions provide planners with a range of robust spatial development patterns known to be best trade-offs which mitigate conflicts between risk and sustainability objectives.

  3. Effects of Demographic Noise on the Synchronization of a Metapopulation in a Fluctuating Environment

    KAUST Repository

    Lai, Yi Ming

    2011-09-08

    We use the theory of noise-induced phase synchronization to analyze the effects of demographic noise on the synchronization of a metapopulation of predator-prey systems within a fluctuating environment (Moran effect). Treating each local predator-prey population as a stochastic urn model, we derive a Langevin equation for the stochastic dynamics of the metapopulation. Assuming each local population acts as a limit cycle oscillator in the deterministic limit, we use phase reduction and averaging methods to derive the steady-state probability density for pairwise phase differences between oscillators, which is then used to determine the degree of synchronization of the metapopulation. © 2011 American Physical Society.

  4. [Health system sustainability from a network perspective: a proposal to optimize healthy habits and social support].

    Science.gov (United States)

    Marqués Sánchez, Pilar; Fernández Peña, Rosario; Cabrera León, Andrés; Muñoz Doyague, María F; Llopis Cañameras, Jaime; Arias Ramos, Natalia

    2013-01-01

    The search of new health management formulas focused to give wide services is one of the priorities of our present health policies. Those formulas examine the optimization of the links between the main actors involved in public health, ie, users, professionals, local socio-political and corporate agents. This paper is aimed to introduce the Social Network Analysis as a method for analyzing, measuring and interpreting those connections. The knowledge of people's relationships (what is called social networks) in the field of public health is becoming increasingly important at an international level. In fact, countries such as UK, Netherlands, Italy, Australia and U.S. are looking formulas to apply this knowledge to their health departments. With this work we show the utility of the ARS on topics related to sustainability of the health system, particularly those related with health habits and social support, topics included in the 2020 health strategies that underline the importance of the collaborative aspects in networks.

  5. Stationary solutions for metapopulation Moran models with mutation and selection

    Science.gov (United States)

    Constable, George W. A.; McKane, Alan J.

    2015-03-01

    We construct an individual-based metapopulation model of population genetics featuring migration, mutation, selection, and genetic drift. In the case of a single "island," the model reduces to the Moran model. Using the diffusion approximation and time-scale separation arguments, an effective one-variable description of the model is developed. The effective description bears similarities to the well-mixed Moran model with effective parameters that depend on the network structure and island sizes, and it is amenable to analysis. Predictions from the reduced theory match the results from stochastic simulations across a range of parameters. The nature of the fast-variable elimination technique we adopt is further studied by applying it to a linear system, where it provides a precise description of the slow dynamics in the limit of large time-scale separation.

  6. Sufficient conditions of endemic threshold on metapopulation networks

    CERN Document Server

    Takaguchi, Taro

    2014-01-01

    In the present paper, we focus on susceptible-infected-susceptible dynamics on metapopulation networks in which nodes represent subpopulations. Recent studies suggest that heterogeneous network structure between elements plays an important role in determining the threshold of infection rate at the onset of epidemics, one of fundamental quantities governing epidemic dynamics. We consider the general case in which the infection rate at each node depends on its population size, as shown in recent empirical observations. We prove that the sufficient condition for the endemic threshold (i.e., its upper bound), which was previously derived based on a mean-field approximation of network structure, also holds true for arbitrary networks. We also derive an improved condition which implies that networks with the rich-club property (that is, high connectivity between nodes with large number of links) are more favorable to disease spreading. The dependency of infection rate on population size introduces remarkable differ...

  7. Host discrimination in modular mutualisms: a theoretical framework for meta-populations of mutualists and exploiters.

    Science.gov (United States)

    Steidinger, Brian S; Bever, James D

    2016-01-13

    Plants in multiple symbioses are exploited by symbionts that consume their resources without providing services. Discriminating hosts are thought to stabilize mutualism by preferentially allocating resources into anatomical structures (modules) where services are generated, with examples of modules including the entire inflorescences of figs and the root nodules of legumes. Modules are often colonized by multiple symbiotic partners, such that exploiters that co-occur with mutualists within mixed modules can share rewards generated by their mutualist competitors. We developed a meta-population model to answer how the population dynamics of mutualists and exploiters change when they interact with hosts with different module occupancies (number of colonists per module) and functionally different patterns of allocation into mixed modules. We find that as module occupancy increases, hosts must increase the magnitude of preferentially allocated resources in order to sustain comparable populations of mutualists. Further, we find that mixed colonization can result in the coexistence of mutualist and exploiter partners, but only when preferential allocation follows a saturating function of the number of mutualists in a module. Finally, using published data from the fig-wasp mutualism as an illustrative example, we derive model predictions that approximate the proportion of exploiter, non-pollinating wasps observed in the field.

  8. Bubonic plague: a metapopulation model of a zoonosis.

    Science.gov (United States)

    Keeling, M J; Gilligan, C A

    2000-01-01

    Bubonic plague (Yersinia pestis) is generally thought of as a historical disease; however, it is still responsible for around 1000-3000 deaths each year worldwide. This paper expands the analysis of a model for bubonic plague that encompasses the disease dynamics in rat, flea and human populations. Some key variables of the deterministic model, including the force of infection to humans, are shown to be robust to changes in the basic parameters, although variation in the flea searching efficiency, and the movement rates of rats and fleas will be considered throughout the paper. The stochastic behaviour of the corresponding metapopulation model is discussed, with attention focused on the dynamics of rats and the force of infection at the local spatial scale. Short-lived local epidemics in rats govern the invasion of the disease and produce an irregular pattern of human cases similar to those observed. However, the endemic behaviour in a few rat subpopulations allows the disease to persist for many years. This spatial stochastic model is also used to identify the criteria for the spread to human populations in terms of the rat density. Finally, the full stochastic model is reduced to the form of a probabilistic cellular automaton, which allows the analysis of a large number of replicated epidemics in large populations. This simplified model enables us to analyse the spatial properties of rat epidemics and the effects of movement rates, and also to test whether the emergent metapopulation behaviour is a property of the local dynamics rather than the precise details of the model. PMID:11413636

  9. An Analysis on the Influence of Network Topologies on Local and Global Dynamics of Metapopulation Systems

    Directory of Open Access Journals (Sweden)

    Daniela Besozzi

    2010-08-01

    Full Text Available Metapopulations are models of ecological systems, describing the interactions and the behavior of populations that live in fragmented habitats. In this paper, we present a model of metapopulations based on the multivolume simulation algorithm tau-DPP, a stochastic class of membrane systems, that we utilize to investigate the influence that different habitat topologies can have on the local and global dynamics of metapopulations. In particular, we focus our analysis on the migration rate of individuals among adjacent patches, and on their capability of colonizing the empty patches in the habitat. We compare the simulation results obtained for each habitat topology, and conclude the paper with some proposals for other research issues concerning metapopulations.

  10. Epidemic modeling in metapopulation systems with heterogeneous coupling pattern: theory and simulations

    CERN Document Server

    Colizza, Vittoria

    2007-01-01

    The spatial structure of populations is a key element in the understanding of the large scale spreading of epidemics. Motivated by the recent empirical evidence on the heterogeneous properties of transportation and commuting patterns among urban areas, we present a thorough analysis of the behavior of infectious diseases in metapopulation models characterized by heterogeneous connectivity and mobility patterns. We derive the basic reaction-diffusion equation describing the metapopulation system at the mechanistic level and derive an early stage dynamics approximation for the subpopulation invasion dynamics. The analytical description uses degree block variables that allows us to take into account arbitrary degree distribution of the metapopulation network. We show that along with the usual single population epidemic threshold the metapopulation network exhibits a global threshold for the subpopulation invasion. We find an explicit analytic expression for the invasion threshold that determines the minimum numb...

  11. Optimization of propranolol HCl release kinetics from press coated sustained release tablets.

    Science.gov (United States)

    Ali, Adel Ahmed; Ali, Ahmed Mahmoud

    2013-01-01

    Press-coated sustained release tablets offer a valuable, cheap and easy manufacture alternative to the highly expensive, multi-step manufacture and filling of coated beads. In this study, propranolol HCl press-coated tablets were prepared using hydroxylpropylmethylcellulose (HPMC) as tablet coating material together with carbopol 971P and compressol as release modifiers. The prepared formulations were optimized for zero-order release using artificial neural network program (INForm, Intelligensys Ltd, North Yorkshire, UK). Typical zero-order release kinetics with extended release profile for more than 12 h was obtained. The most important variables considered by the program in optimizing formulations were type and proportion of polymer mixture in the coat layer and distribution ratio of drug between core and coat. The key elements found were; incorporation of 31-38 % of the drug in the coat, fixing the amount of polymer in coat to be not less than 50 % of coat layer. Optimum zero-order release kinetics (linear regression r2 = 0.997 and Peppas model n value > 0.80) were obtained when 2.5-10 % carbopol and 25-42.5% compressol were incorporated into the 50 % HPMC coat layer.

  12. Optimal waste-to-energy strategy assisted by GIS For sustainable solid waste management

    Science.gov (United States)

    Tan, S. T.; Hashim, H.

    2014-02-01

    Municipal solid waste (MSW) management has become more complex and costly with the rapid socio-economic development and increased volume of waste. Planning a sustainable regional waste management strategy is a critical step for the decision maker. There is a great potential for MSW to be used for the generation of renewable energy through waste incineration or landfilling with gas capture system. However, due to high processing cost and cost of resource transportation and distribution throughout the waste collection station and power plant, MSW is mostly disposed in the landfill. This paper presents an optimization model incorporated with GIS data inputs for MSW management. The model can design the multi-period waste-to-energy (WTE) strategy to illustrate the economic potential and tradeoffs for MSW management under different scenarios. The model is capable of predicting the optimal generation, capacity, type of WTE conversion technology and location for the operation and construction of new WTE power plants to satisfy the increased energy demand by 2025 in the most profitable way. Iskandar Malaysia region was chosen as the model city for this study.

  13. Human-facilitated metapopulation dynamics in an emerging pest species, Cimex lectularius

    OpenAIRE

    Fountain, T; Duvaux, L; Horsburgh, G.; Reinhardt, K.; Butlin, R. K.

    2014-01-01

    The number and demographic history of colonists can have dramatic consequences for the way in which genetic diversity is distributed and maintained in a metapopulation. The bed bug (Cimex lectularius) is a re-emerging pest species whose close association with humans has led to frequent local extinction and colonization, that is, to metapopulation dynamics. Pest control limits the lifespan of subpopulations, causing frequent local extinctions, and human-facilitated dispersal allows the coloniz...

  14. Optimization of an Efficient and Sustainable Sonogashira Cross-Coupling Protocol

    KAUST Repository

    Walter, Philipp E.

    2012-12-01

    Cross coupling reactions are a well-established tool in modern organic synthesis and play a crucial role in the synthesis of a high number of organic compounds. Their importance is highlighted by the Nobel Prize in chemistry to Suzuki, Heck and Negishi in 2010. The increasing importance of sustainability requirements in chemical production has furthermore promoted the development of cross-coupling protocols that comply with the principles of “Green Chemistry”1. The Sonogashira reaction is today the most versatile and powerful way to generate aryl alkynes, a moiety recurring in many pharmaceutical and natural products. Despite many improvements to the original reaction, reports on generally applicable protocols that work under sustainable conditions are scarce. Our group recently reported an efficient protocol for a copperfree Sonogashira cross-coupling at low temperature, in aqueous medium and with no addition of organic solvents or additives2. The goal of this work was to further investigate the effects of different reaction parameters on the catalytic activity in order to optimize the protocol. Limitations of the protocol were tested in respect to reaction temperature, heating method, atmosphere, base type and amount, catalyst loading, reaction time and work up procedure. The reaction worked successfully under air and results were not affected by the presence of oxygen in the water phase. Among a variety of bases tested, triethylamine was confirmed to give the best results and its required excess could be reduced from nine to four equivalents. Catalyst loading could also be reduced by up to 90%: Good to near quantitative yields for a broad range of substrates were achieved using a catalyst concentration of 0.25mol% and 5 eq of Et3N at 50°C while more reactive substrates could be coupled with a catalyst concentration as low as 0.025mol%. Filtration experiments showed the possibility of a simplified work up procedure and a protocol completely free of organic

  15. The Optimization of Rural Landscape in the Light of the Idea of Sustainable Development – The Example of Poland

    Directory of Open Access Journals (Sweden)

    Sobala Michał

    2016-09-01

    Full Text Available Contemporary rural landscapes in Poland are being changed intensively and adversely. These changes lead to landscape disharmony, spatial disorder, the blurring of individual and specific features and disruption to the ecological equilibrium. This article aims to present general rules for the optimization of rural landscapes. It discusses the causes and consequences of unfavourable changes within Poland’s rural landscapes which constitute a threat to their sustainable development. The authors attempt to identify the major factors to be considered in taking steps aimed at landscape optimization. Landscape equilibrium may be assessed through the sustainable development dimensions: ethical, ecological, social, economic, technical, political and legal. Landscape optimization consists in maintaining the balance within these dimensions.

  16. Are the Economically Optimal Harvesting Strategies of Uneven-Aged Pinus nigra Stands Always Sustainable and Stabilizing?

    Directory of Open Access Journals (Sweden)

    Carmen Fullana-Belda

    2013-10-01

    Full Text Available Traditional uneven-aged forest management seeks a balance between equilibrium stand structure and economic profitability, which often leads to harvesting strategies concentrated in the larger diameter classes. The sustainability (i.e., population persistence over time and influence of such economically optimal strategies on the equilibrium position of a stand (given by the stable diameter distribution have not been sufficiently investigated in prior forest literature. This article therefore proposes a discrete optimal control model to analyze the sustainability and stability of the economically optimal harvesting strategies of uneven-aged Pinus nigra stands. For this model, we rely on an objective function that integrates financial data of harvesting operations with a projection matrix model that can describe the population dynamics. The model solution reveals the optimal management schedules for a wide variety of scenarios. To measure the distance between the stable diameter distribution and the economically optimal harvesting strategy distribution, the model uses Keyfitz’s delta, which returns high values for all the scenarios and, thus, suggests that those economically optimal harvesting strategies have an unstabilizing influence on the equilibrium positions. Moreover, the economically optimal harvesting strategies were unsustainable for all the scenarios.

  17. PARTITION-OPTIMIZED SINGLE EMULSION PARTICLES IMPROVE SUSTAINED RELEASE OF AMPHIPHILIC BUMPED KINASE INHIBITORS TO CONTROL MALARIA TRANSMISSION

    Directory of Open Access Journals (Sweden)

    Christina Yacoob

    2015-11-01

    Full Text Available Amphiphilic molecules are challenging to be incorporatedinto polymeric particles for sustained release due to their significant solubility in both water and organic solvent used in the fabrication process. Here, we investigated an extensive panel of fabrication methods for the incorporation and release of amphiphilic molecules, in particular, novel amphiphilic bumped kinase inhibitors (BKIs. Previously, BKIswere shown to reduce malaria transmission by blocking of gametocyte exflagellation. Prolonged BKI bioavailability for effective transmission blocking is crucial since infectious gametocytes circulate for several weeks inthe mammalian host, well beyond the half-life of BKIs. So far, delivery systems for sustained release of those BKIs have not been successfully formulated yet. Here we demonstrate that out of several delivery vehicles the partition-optimized single emulsion particles are the ideal system for incorporation and sustained release of amphiphilic BKIs. They increased the incorporation greater than 90% through optimized partitioning of amphiphilic molecules to the polymer phase and sustained release of BKIs up to several weeks with a reduction in the initial burst release. Overall this work provides a method for the incorporation and sustained release of amphiphilic BKIs, and can be adapted for other amphiphilic molecules.

  18. Past, growth and persistence of source-sink metapopulations

    CERN Document Server

    Bansaye, Vincent

    2011-01-01

    Source-sink systems are metapopulations of patches that can be of variable habitat quality. They can be seen as graphs, where vertices represent the patches, and the weighted oriented edges give the probability of dispersal from one patch to another. We consider either finite or source-transitive graphs, i.e., graphs that are identical when viewed from a(ny) source. We assume stochastic, individual-based, density-independent reproduction and dispersal. By studying the path of a single random disperser, we are able to display simple criteria for persistence, either necessary and sufficient, or just sufficient. In case of persistence, we characterize the growth rate of the population as well as the asymptotic occupancy frequencies of the line of ascent of a random survivor. Our method allows to decouple the roles of reproduction and dispersal. Finally, we extend our results to the case of periodic or random environments, where some habitats can have variable growth rates, autocorrelated in space and possibly in...

  19. Effects of Lead Exposure, Environmental Conditions, and Metapopulation Processes on Population Dynamics of Spectacled Eiders.

    Science.gov (United States)

    Flint, Paul L.; Grand, James B.; Petersen, Margaret; Robert Rockwell,

    2016-01-01

    Spectacled eider Somateria fischeri numbers have declined and they are considered threatened in accordance with the US Endangered Species Act throughout their range. We synthesized the available information for spectacled eiders to construct deterministic, stochastic, and metapopulation models for this species that incorporated current estimates of vital rates such as nest success, adult survival, and the impact of lead poisoning on survival. Elasticities of our deterministic models suggested that the populations would respond most dramatically to changes in adult female survival and that the reductions in adult female survival related to lead poisoning were locally important. We also examined the sensitivity of the population to changes in lead exposure rates. With the knowledge that some vital rates vary with environmental conditions, we cast stochastic models that mimicked observed variation in productivity. We also used the stochastic model to examine the probability that a specific population will persist for periods of up to 50 y. Elasticity analysis of these models was consistent with that for the deterministic models, with perturbations to adult female survival having the greatest effect on population projections. When used in single population models, demographic data for some localities predicted rapid declines that were inconsistent with our observations in the field. Thus, we constructed a metapopulation model and examined the predictions for local subpopulations and the metapopulation over a wide range of dispersal rates. Using the metapopulation model, we were able to simulate the observed stability of local subpopulations as well as that of the metapopulation. Finally, we developed a global metapopulation model that simulates periodic winter habitat limitation, similar to that which might be experienced in years of heavy sea ice in the core wintering area of spectacled eiders in the central Bering Sea. Our metapopulation analyses suggested that no

  20. Demographic stochasticity reduces the synchronizing effect of dispersal in predator-prey metapopulations.

    Science.gov (United States)

    Simonis, Joseph L

    2012-07-01

    Dispersal may affect predator-prey metapopulations by rescuing local sink populations from extinction or by synchronizing population dynamics across the metapopulation, increasing the risk of regional extinction. Dispersal is likely influenced by demographic stochasticity, however, particularly because dispersal rates are often very low in metapopulations. Yet the effects of demographic stochasticity on predator-prey metapopulations are not well known. To that end, I constructed three models of a two-patch predator-prey system. The models constitute a hierarchy of complexity, allowing direct comparisons. Two models included demographic stochasticity (pure jump process [PJP] and stochastic differential equations [SDE]), and the third was deterministic (ordinary differential equations [ODE]). One stochastic model (PJP) treated population sizes as discrete, while the other (SDE) allowed population sizes to change continuously. Both stochastic models only produced synchronized predator-prey dynamics when dispersal was high for both trophic levels. Frequent dispersal by only predators or prey in the PJP and SDE spatially decoupled the trophic interaction, reducing synchrony of the non-dispersive species. Conversely, the ODE generated synchronized predator-prey dynamics across all dispersal rates, except when initial conditions produced anti-phase transients. These results indicate that demographic stochasticity strongly reduces the synchronizing effect of dispersal, which is ironic because demographic stochasticity is often invoked post hoc as a driver of extinctions in synchronized metapopulations.

  1. Optimization of sustainable buildings envelopes for extensive sheep farming through the use of dynamic energy simulation

    Directory of Open Access Journals (Sweden)

    Maria Elena Menconi

    2013-09-01

    Full Text Available Extensive sheep farming can be seen as a marginal market, compared to other livestock and agricultural activities, taking into account only the economic absolute values. But for many rural marginal areas within the European Community member states, in particular for those located in the Mediterranean area on hills or mountains with high landscape value, extensive sheep farming is not only the longest practiced animal farming activity, but also the most interesting considering its adaptability to the territorial morphology and the restrictions that have been established over the years in terms of sustainable rural development practices. At the moment, most of the structures used in this type of farming are built using low cost and sometimes recycled, but often unsuitable, materials. Few specific studies have been carried out on this particular issue assuming, presumably, that the very low profit margins of these activities made impossible any restructuring. Taken this into account, the new Rural Development Plans that will be issued in 2014 will surely contain some measure dedicated to innovations in farming structures and technology towards facilitating the application of the principles of energy optimization. This is the framework in which the present research has developed. The software that has been applied to perform the energy optimization analysis is the dynamic energy simulation engine Energy Plus. A case study farm has been identified in the small village of Ceseggi (PG, situated in Central Italy. For the case study optimum thermo hygrometric conditions have been identified to ensure the welfare of animals and operators and it has been hypothesized the insertion of an ideal HVAC system to achieve them. Afterwards were evaluated the different energy requirements of the building while varying the insulation material used on the vertical surfaces. The greater goal is to verify which could be the best insulation material for vertical

  2. Persistence in epidemic metapopulations: quantifying the rescue effects for measles, mumps, rubella and whooping cough.

    Science.gov (United States)

    Metcalf, C Jessica E; Hampson, Katie; Tatem, Andrew J; Grenfell, Bryan T; Bjørnstad, Ottar N

    2013-01-01

    Metapopulation rescue effects are thought to be key to the persistence of many acute immunizing infections. Yet the enhancement of persistence through spatial coupling has not been previously quantified. Here we estimate the metapopulation rescue effects for four childhood infections using global WHO reported incidence data by comparing persistence on island countries vs all other countries, while controlling for key variables such as vaccine cover, birth rates and economic development. The relative risk of extinction on islands is significantly higher, and approximately double the risk of extinction in mainland countries. Furthermore, as may be expected, infections with longer infectious periods tend to have the strongest metapopulation rescue effects. Our results quantitate the notion that demography and local community size controls disease persistence.

  3. Persistence in epidemic metapopulations: quantifying the rescue effects for measles, mumps, rubella and whooping cough.

    Directory of Open Access Journals (Sweden)

    C Jessica E Metcalf

    Full Text Available Metapopulation rescue effects are thought to be key to the persistence of many acute immunizing infections. Yet the enhancement of persistence through spatial coupling has not been previously quantified. Here we estimate the metapopulation rescue effects for four childhood infections using global WHO reported incidence data by comparing persistence on island countries vs all other countries, while controlling for key variables such as vaccine cover, birth rates and economic development. The relative risk of extinction on islands is significantly higher, and approximately double the risk of extinction in mainland countries. Furthermore, as may be expected, infections with longer infectious periods tend to have the strongest metapopulation rescue effects. Our results quantitate the notion that demography and local community size controls disease persistence.

  4. Predicting Metapopulation Responses To Conservation In Human-Dominated Landscapes

    Directory of Open Access Journals (Sweden)

    Zachary S. Ladin

    2016-10-01

    Full Text Available Loss of habitat to urbanization is a primary cause of population declines as human-dominated landscapes expand at increasing rates. Understanding how the relative effects of different conservation strategies is important to slow population declines for species in urban landscapes. We studied the wood thrush Hylocichla mustelina, a declining forest-breeding Neotropical migratory species, and umbrella species for forest-breeding songbirds, within the urbanized mid-Atlantic United States. We integrated 40 years of demographic data with contemporary metapopulation model simulations of breeding wood thrushes to predict population responses to differing conservation scenarios. We compared four conservation scenarios over a 30-year time period (2014–2044 representing A current observed state (Null, B replacing impervious surface with forest (Reforest, C reducing brown-headed cowbird Molothrus ater parasitism pressure (Cowbird removal, and D simultaneous reforesting and cowbird removal. Compared to the Null scenario, the Reforest scenario increased mean annual population trends by 54 % , the Remove cowbirds scenario increased mean annual population trends by 38 %, and the scenario combining reforestation and cowbird removal increased mean annual population trends by 98 %. Mean annual growth rates (λ per site were greater in the Reforest (λ = 0.94 and Remove cowbirds (λ = 0.92 compared to the Null (λ = 0.88 model scenarios. However, only by combining the positive effects of reforestation and cowbird removal did wood thrush populations stop declining (λ = 1.00. Our results suggest that independently replacing impervious surface with forest habitat around forest patches and removing cowbirds may slow current negative population trends. Furthermore, conservation efforts that combine reforestation and cowbird removal may potentially benefit populations of wood thrushes and other similarly forest-breeding songbird species within urbanized fragmented

  5. Application of multi-objective optimization based on genetic algorithm for sustainable strategic supplier selection under fuzzy environment

    Directory of Open Access Journals (Sweden)

    Muhammad Hashim

    2017-05-01

    Full Text Available Purpose:  The incorporation of environmental objective into the conventional supplier selection practices is crucial for corporations seeking to promote green supply chain management (GSCM. Challenges and risks associated with green supplier selection have been broadly recognized by procurement and supplier management professionals. This paper aims to solve a Tetra “S” (SSSS problem based on a fuzzy multi-objective optimization with genetic algorithm in a holistic supply chain environment. In this empirical study, a mathematical model with fuzzy coefficients is considered for sustainable strategic supplier selection (SSSS problem and a corresponding model is developed to tackle this problem. Design/methodology/approach: Sustainable strategic supplier selection (SSSS decisions are typically multi-objectives in nature and it is an important part of green production and supply chain management for many firms. The proposed uncertain model is transferred into deterministic model by applying the expected value mesurement (EVM and genetic algorithm with weighted sum approach for solving the multi-objective problem. This research focus on a multi-objective optimization model for minimizing lean cost, maximizing sustainable service and greener product quality level. Finally, a mathematical case of textile sector is presented to exemplify the effectiveness of the proposed model with a sensitivity analysis. Findings: This study makes a certain contribution by introducing the Tetra ‘S’ concept in both the theoretical and practical research related to multi-objective optimization as well as in the study of sustainable strategic supplier selection (SSSS under uncertain environment. Our results suggest that decision makers tend to select strategic supplier first then enhance the sustainability. Research limitations/implications: Although the fuzzy expected value model (EVM with fuzzy coefficients constructed in present research should be helpful for

  6. Development of sustainable stormwater management using simulation-optimization approach under climate change

    Science.gov (United States)

    Huang, Yu-ru; Tung, Ching-pin

    2015-04-01

    Climate change had altered the hydrological processes globally with result that the extreme events have an increase in both the magnitude and the frequency. In particular, the high intensity rainfall cause the severe flooding had significantly impacted on human life and property in recently year. The traditional facility to handle runoff is the drainage system which is designed in accordance with the intensity-duration-frequency (IDF) curve. However, the flooding occurs once the drainage capacity is overwhelmed by excess stormwater. Thus the general solution are that expanding and upgrading the existing drainage system or increasing the design return period for new development areas to reduce flooding. Besides, another technique which is low impact development(LID) is regarded as more sustainable solution for stormwater management. The concept of LID is to control stormwater at the source by decentralized practices and mimic the predevelopment hydrologic conditions including storage, retention and high rate of infiltration. In contrast to conventional drainage system aims to move runoff away as quickly as possible, the LID approach attempts to keep runoff on site to reduce peak and volume of flow. The purpose of this research is to identify the most cost-effective measures for stormwater management after the analysis of the strategies combining drainage system and LID on various land use planning. The case study is a rural community in Hsinchu in Taiwan, and having residential areas, farms and pond. It is assumed that two land use layout are planned and drainage system are designed for 2-,and 5-year return period events. On the other hand, three LID technologies, namely green roof, porous pavement and rain barrel, are selected to place in the scenario of the drainage system for 2-year return period event, and the minimal peak flow is target to optimize LID placement by simulated annealing algorithm. Moreover, the design storm under climate change are derived from

  7. Forced sustained swimming exercise at optimal speed enhances growth of juvenile yellowtail kingfish (Seriola lalandi)

    NARCIS (Netherlands)

    Palstra, A.P.; Mes, D.; Kusters, K.; Roques, J.A.C.; Flik, G.; Kloet, K.; Blonk, R.J.W.

    2015-01-01

    Swimming exercise at optimal speed may optimize growth performance of yellowtail kingfish in a recirculating aquaculture system. Therefore, optimal swimming speeds (U-opt in m s(-1) or body lengths s(-1), BL s(-1)) were assessed and then applied to determine the effects of long-term forced and

  8. A Multiobjective Optimization Model of Production-Sourcing for Sustainable Supply Chain with Consideration of Social, Environmental, and Economic Factors

    Directory of Open Access Journals (Sweden)

    Zhixiang Chen

    2014-01-01

    Full Text Available This paper incorporates the three pillars of sustainability—economic, environmental, and social dimensions—into a supply chain. A multiobjective programming model which jointly minimizes costs, emissions, and employee injuries in a supply chain is first constructed. Using the weighted-sum approach with weights setting by the analytic hierarchy process (AHP, the model is solved by normalization of the minima of the three objectives. A numerical example is conducted to test the model. The results show that it is indeed possible to integrate environmental and social metrics in supply chain system optimization. Multiobjective optimization can balance the social, environmental, and economic performance. This paper presents a new multidimension perspective for optimizing supply chain; it will inspire practitioners to change their decision ideas and improve supply chain sustainability.

  9. Is local participation always optimal for sustainable action? The costs of consensus-building in Local Agenda 21.

    Science.gov (United States)

    Brandt, Urs Steiner; Svendsen, Gert Tinggaard

    2013-11-15

    Is local participation always optimal for sustainable action? Here, Local Agenda 21 is a relevant case as it broadly calls for consensus-building among stakeholders. Consensus-building is, however, costly. We show that the costs of making local decisions are likely to rapidly exceed the benefits. Why? Because as the number of participants grows, the more likely it is that the group will include individuals who have an extreme position and are unwilling to make compromises. Thus, the net gain of self-organization should be compared with those of its alternatives, for example voting, market-solutions, or not making any choices at all. Even though the informational value of meetings may be helpful to policy makers, the model shows that it also decreases as the number of participants increase. Overall, the result is a thought provoking scenario for Local Agenda 21 as it highlights the risk of less sustainable action in the future.

  10. An Analysis of Policy Optimization concerning Sustainable Agricultural Development in China Based on 2014 US Farm Bill

    Institute of Scientific and Technical Information of China (English)

    Zhongxing LI; Joseph J.Molnar; Shunqiang SUN

    2016-01-01

    On the basis of ensuring farmers’ income,the US 2014 Farm Bill emphasizes resources and environmental protection,and some policies and measures to promote rural development,sustainable agricultural development and agricultural science and technology,which provides a good lesson for China’s agricultural policy on how to ensure sustainable agricultural development. Finally,we set forth the following recommendations: speeding up the establishment of a legal system of modern agriculture; optimizing agricultural safety net and strengthening agricultural risk management and control; establishing agricultural science and technology extension system and adjusting agricultural planting structure; establishing farmers’ associations,nurturing new farmers and protecting the legitimate rights and interests of farmers; increasing environmental remediation investment and efforts.

  11. Lumpers or splitters? Evaluating recovering and management plans for metapopulations of herring

    NARCIS (Netherlands)

    Kell, L.T.; Dickey-Collas, M.; Hintzen, N.T.; Nash, R.D.M.; Pilling, G.M.

    2009-01-01

    The long-term management of a stock representing a metapopulation has been simulated in a case study loosely based upon herring to the west of the British isles, where stocks are currently assessed and managed by management area, although there is evidence of mixing between stocks (in terms of conne

  12. 3Sex-specific dispersal and evolutionary rescue in metapopulations infected by male killing endosymbionts

    Directory of Open Access Journals (Sweden)

    Hovestadt Thomas

    2009-01-01

    Full Text Available Abstract Background Male killing endosymbionts manipulate their arthropod host reproduction by only allowing female embryos to develop into infected females and killing all male offspring. Because the resulting change in sex ratio is expected to affect the evolution of sex-specific dispersal, we investigated under which environmental conditions strong sex-biased dispersal would emerge, and how this would affect host and endosymbiont metapopulation persistence. Results We simulated host-endosymbiont metapopulation dynamics in an individual-based model, in which dispersal rates are allowed to evolve independently for the two sexes. Prominent male-biased dispersal emerges under conditions of low environmental stochasticity and high dispersal mortality. By applying a reshuffling algorithm, we show that kin-competition is a major driver of this evolutionary pattern because of the high within-population relatedness of males compared to those of females. Moreover, the evolution of sex-specific dispersal rescues metapopulations from extinction by (i reducing endosymbiont fixation rates and (ii by enhancing the extinction of endosymbionts within metapopulations that are characterized by low environmental stochasticity. Conclusion Male killing endosymbionts induce the evolution of sex-specific dispersal, with prominent male-biased dispersal under conditions of low environmental stochasticity and high dispersal mortality. This male-biased dispersal emerges from stronger kin-competition in males compared to females and induces an evolutionary rescue mechanism.

  13. Metapopulations in agricultural landscapes: a spatially explicit trade-off analysis

    NARCIS (Netherlands)

    Groeneveld, R.A.; Grashof-Bokdam, C.J.; Ierland, van E.C.

    2005-01-01

    This paper presents a spatially explicit trade-off analysis of species conservation in agricultural areas. A spatially explicit model is presented that integrates an applied metapopulation model with a farm management model. The model is used to calculate production possibilities frontiers of net mo

  14. Response surface methodology and process optimization of sustained release pellets using Taguchi orthogonal array design and central composite design

    Directory of Open Access Journals (Sweden)

    Gurinder Singh

    2012-01-01

    Full Text Available Furosemide is a powerful diuretic and antihypertensive drug which has low bioavailability due to hepatic first pass metabolism and has a short half-life of 2 hours. To overcome the above drawback, the present study was carried out to formulate and evaluate sustained release (SR pellets of furosemide for oral administration prepared by extrusion/spheronization. Drug Coat L-100 was used within the pellet core along with microcrystalline cellulose as the diluent and concentration of selected binder was optimized to be 1.2%. The formulation was prepared with drug to polymer ratio 1:3. It was optimized using Design of Experiments by employing a 3 2 central composite design that was used to systematically optimize the process parameters combined with response surface methodology. Dissolution studies were carried out with USP apparatus Type I (basket type in both simulated gastric and intestinal pH. The statistical technique, i.e., the two-tailed paired t test and one-way ANOVA of in vitro data has proposed that there was very significant ( P≤0.05 difference in dissolution profile of furosemide SR pellets when compared with pure drug and commercial product. Validation of the process optimization study indicated an extremely high degree of prognostic ability. The study effectively undertook the development of optimized process parameters of pelletization of furosemide pellets with tremendous SR characteristics.

  15. Response surface methodology and process optimization of sustained release pellets using Taguchi orthogonal array design and central composite design.

    Science.gov (United States)

    Singh, Gurinder; Pai, Roopa S; Devi, V Kusum

    2012-01-01

    Furosemide is a powerful diuretic and antihypertensive drug which has low bioavailability due to hepatic first pass metabolism and has a short half-life of 2 hours. To overcome the above drawback, the present study was carried out to formulate and evaluate sustained release (SR) pellets of furosemide for oral administration prepared by extrusion/spheronization. Drug Coat L-100 was used within the pellet core along with microcrystalline cellulose as the diluent and concentration of selected binder was optimized to be 1.2%. The formulation was prepared with drug to polymer ratio 1:3. It was optimized using Design of Experiments by employing a 3(2) central composite design that was used to systematically optimize the process parameters combined with response surface methodology. Dissolution studies were carried out with USP apparatus Type I (basket type) in both simulated gastric and intestinal pH. The statistical technique, i.e., the two-tailed paired t test and one-way ANOVA of in vitro data has proposed that there was very significant (P≤0.05) difference in dissolution profile of furosemide SR pellets when compared with pure drug and commercial product. Validation of the process optimization study indicated an extremely high degree of prognostic ability. The study effectively undertook the development of optimized process parameters of pelletization of furosemide pellets with tremendous SR characteristics.

  16. Extinction, reintroduction, and restoration of a lizard meta-population equilibrium in the Missouri Ozarks.

    Science.gov (United States)

    Sites, Jack W

    2013-07-01

    In this issue of Molecular Ecology, Neuwald & Templeton (2013) report on a 22-year study of natural populations of Collared Lizards (Crotaphytus collaris) that evolved on isolated on rock outcrops (‘glades’) in the Ozark Mountains in eastern Missouri. This ecosystem was originally maintained by frequent fires that kept the forest understory open, but fire-suppression was adopted as official policy in about 1945, which led to a loss of native biodiversity, including local extinctions of some lizard populations. Policies aimed at restoring biodiversity included controlled burns and re-introductions of lizards to some glades, which began in 1984. Populations were monitored from 1984–2006, and demographic and genetic data collected from 1 679 lizards were used to documents shifts in meta-population dynamics over four distinct phases of lizard recovery: 1–an initial translocation of lizards drawn from the same source populations onto three glades that were likely part of one metapopulation; 2–a period of isolation and genetic drift associated with the absence of fires; 3–a period of rapid colonization and population increase following restoration of fire; and 4–stabilization of the meta-population under regular prescribed burning. This study system thus provides a rare opportunity to characterize the dynamics of a landscape-scale management strategy on the restoration of the meta-population of a reintroduced species; long-term case studies of the extinction, founding, increase, and stabilization of a well-defined meta-population, based on both demographic and population genetic data, are rare in the conservation, ecological, and evolutionary literature.

  17. Contingency Contractor Optimization Phase 3 Sustainment Verification and Validation V&V) Report - Contingency Contractor Optimization Engineering - Prototype

    Energy Technology Data Exchange (ETDEWEB)

    Bandlow, Alisa [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Operations Research and Computational Analysis; Durfee, Justin David [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Operations Research and Computational Analysis; Frazier, Christopher Rawls [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Operations Research and Computational Analysis; Gearhart, Jared Lee [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Operations Research and Computational Analysis; Jones, Katherine A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Operations Research and Computational Analysis; Adair, Kristin Lynn [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Operations Research and Computational Analysis; Turgeon, Jennifer [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). High Confidence System Environments

    2016-04-01

    The reports and test plans contained within this document serve as supporting materials to the activities listed within the “Contingency Contractor Optimization Tool – Prototype (CCOT-P) Verification & Validation Plan” [1]. The activities included test development, testing, peer reviews, and expert reviews. The engineering prototype reviews were done for both the software and the mathematical model used in CCOT-P. Section 2 includes the peer and expert review reports, which summarize the findings from each of the reviews and document the resolution of any issues. Section 3 details the test plans that were followed for functional testing of the application through the interface. Section 4 describes the unit tests that were run on the code.

  18. Optimal Scheduling of Energy Storage System for Self-Sustainable Base Station Operation Considering Battery Wear-Out Cost

    Directory of Open Access Journals (Sweden)

    Yohwan Choi

    2016-06-01

    Full Text Available A self-sustainable base station (BS where renewable resources and energy storage system (ESS are interoperably utilized as power sources is a promising approach to save energy and operational cost in communication networks. However, high battery price and low utilization of ESS intended for uninterruptible power supply (UPS necessitates active utilization of ESS. This paper proposes a multi-functional framework of ESS using dynamic programming (DP for realizing a sustainable BS. We develop an optimal charging and discharging scheduling algorithm considering a detailed battery wear-out model to minimize operational cost as well as to prolong battery lifetime. Our approach significantly reduces total cost compared to the conventional method that does not consider battery wear-out. Extensive experiments for several scenarios exhibit that total cost is reduced by up to 70.6% while battery wear-out is also reduced by 53.6%. The virtue of the proposed framework is its wide applicability beyond sustainable BS and thus can be also used for other types of load in principle.

  19. A sustainable manufacturing system design: A fuzzy multi-objective optimization model.

    Science.gov (United States)

    Nujoom, Reda; Mohammed, Ahmed; Wang, Qian

    2017-08-10

    In the past decade, there has been a growing concern about the environmental protection in public society as governments almost all over the world have initiated certain rules and regulations to promote energy saving and minimize the production of carbon dioxide (CO2) emissions in many manufacturing industries. The development of sustainable manufacturing systems is considered as one of the effective solutions to minimize the environmental impact. Lean approach is also considered as a proper method for achieving sustainability as it can reduce manufacturing wastes and increase the system efficiency and productivity. However, the lean approach does not include environmental waste of such as energy consumption and CO2 emissions when designing a lean manufacturing system. This paper addresses these issues by evaluating a sustainable manufacturing system design considering a measurement of energy consumption and CO2 emissions using different sources of energy (oil as direct energy source to generate thermal energy and oil or solar as indirect energy source to generate electricity). To this aim, a multi-objective mathematical model is developed incorporating the economic and ecological constraints aimed for minimization of the total cost, energy consumption, and CO2 emissions for a manufacturing system design. For the real world scenario, the uncertainty in a number of input parameters was handled through the development of a fuzzy multi-objective model. The study also addresses decision-making in the number of machines, the number of air-conditioning units, and the number of bulbs involved in each process of a manufacturing system in conjunction with a quantity of material flow for processed products. A real case study was used for examining the validation and applicability of the developed sustainable manufacturing system model using the fuzzy multi-objective approach.

  20. Evaluation and Optimization of the Financial Sustainability of Public Rental Housing Projects: A Case Study in Nanjing, China

    Directory of Open Access Journals (Sweden)

    Dezhi Li

    2016-04-01

    Full Text Available In recent years, Chinese governments have launched ambitious plans in developing public rental housing (PRH, which are almost impossible to accomplish without the involvement of the private sector. Yet, very few quantitative studies have been carried out to evaluate the financial sustainability of PRH projects in China, especially from the perspective of the private sector. This knowledge gap is bridged through the evaluation of the financial sustainability of a hypothetical privately owned PRH project in Nanjing, China as a case study, utilizing data of a state-owned PRH project and the classic discounted cash flow method. The results indicate that the studied project is financially infeasible, which means that private companies would not be willing to participate in the provision of public rental housing, if they merely focus on profits. Then, the most cost-effective optimization measure of the studied case is quantitatively selected from four possible optimization scenarios, leading to a financial balance. This paper presents the current financial status of Chinese PRH projects, thereby providing policy makers with useful references to effectively accelerate the private sector’s provision of PRH in China.

  1. Metapopulation theory identifies biogeographical patterns among core and satellite marine bacteria scaling from tens to thousands of kilometers

    DEFF Research Database (Denmark)

    Lindh, Markus V.; Sjöstedt, Johanna; Ekstam, Börje

    2017-01-01

    with a satellite mode of rare endemic populations and a core mode of abundant cosmopolitan populations (e.g. Synechococcus, SAR11 and SAR86 clade members). Temporal changes in population distributions supported several theoretical frameworks. Still, bimodality was found among bacterioplankton communities across......Metapopulation theory developed in terrestrial ecology provides applicable frameworks for interpreting the role of local and regional processes in shaping species distribution patterns. Yet, empirical testing of metapopulation models on microbial communities is essentially lacking. We determined...

  2. Hunting for the optimal hunt - Contributions to a sustainable harvest strategy for pink-footed geese

    DEFF Research Database (Denmark)

    Jensen, Gitte Høj

    in order to reduce conflicts with agriculture and degradation of tundra vegetation in Svalbard. The population target shall be achieved through an adaptive harvest management (AHM) framework and optimization of hunting practices and organisation. The objective of this thesis has been to support...... the development of the AHM plan. This has been done at the flyway level by developing demographic population models and exploring the application of dynamic optimization methods to find an optimal management strategy. At the local and regional levels I explored effects of hunting practises and organisation at one......As part of the recently endorsed African-Eurasian Migratory Waterbird (AEWA) International Species Management Plan for the Svalbard population of the pink-footed goose Anser brachyrhynchus, a stable population target of 60,000 (current population is c. 80,000 during 2011-2013) has been agreed...

  3. Sustainable housing in Vietnam: Climate responsive design strategies to optimize thermal comfort

    OpenAIRE

    2013-01-01

    Housing issue in Vietnam is still a big concern as in 2008, 72.2% of the existing housing was semi-permanent or temporary and 89.2% of the poor did not have a permanent shelter. As a response to sustainability, the global aim of this thesis is to develop design strategies toward comfortable, energy-efficient housing with acceptable building cost. Occupants’ thermal comfort is the key assessment criterion throughout the research. First of all, the thesis develops a thermal comfort model fo...

  4. Climate variables explain neutral and adaptive variation within salmonid metapopulations: the importance of replication in landscape genetics.

    Science.gov (United States)

    Hand, Brian K; Muhlfeld, Clint C; Wade, Alisa A; Kovach, Ryan P; Whited, Diane C; Narum, Shawn R; Matala, Andrew P; Ackerman, Michael W; Garner, Brittany A; Kimball, John S; Stanford, Jack A; Luikart, Gordon

    2016-02-01

    Understanding how environmental variation influences population genetic structure is important for conservation management because it can reveal how human stressors influence population connectivity, genetic diversity and persistence. We used riverscape genetics modelling to assess whether climatic and habitat variables were related to neutral and adaptive patterns of genetic differentiation (population-specific and pairwise FST ) within five metapopulations (79 populations, 4583 individuals) of steelhead trout (Oncorhynchus mykiss) in the Columbia River Basin, USA. Using 151 putatively neutral and 29 candidate adaptive SNP loci, we found that climate-related variables (winter precipitation, summer maximum temperature, winter highest 5% flow events and summer mean flow) best explained neutral and adaptive patterns of genetic differentiation within metapopulations, suggesting that climatic variation likely influences both demography (neutral variation) and local adaptation (adaptive variation). However, we did not observe consistent relationships between climate variables and FST across all metapopulations, underscoring the need for replication when extrapolating results from one scale to another (e.g. basin-wide to the metapopulation scale). Sensitivity analysis (leave-one-population-out) revealed consistent relationships between climate variables and FST within three metapopulations; however, these patterns were not consistent in two metapopulations likely due to small sample sizes (N = 10). These results provide correlative evidence that climatic variation has shaped the genetic structure of steelhead populations and highlight the need for replication and sensitivity analyses in land and riverscape genetics.

  5. Climate variables explain neutral and adaptive variation within salmonid metapopulations: The importance of replication in landscape genetics

    Science.gov (United States)

    Hand, Brian K; Muhlfeld, Clint C.; Wade, Alisa A.; Kovach, Ryan; Whited, Diane C.; Narum, Shawn R.; Matala, Andrew P; Ackerman, Michael W.; Garner, B. A.; Kimball, John S; Stanford, Jack A.; Luikart, Gordon

    2016-01-01

    Understanding how environmental variation influences population genetic structure is important for conservation management because it can reveal how human stressors influence population connectivity, genetic diversity and persistence. We used riverscape genetics modelling to assess whether climatic and habitat variables were related to neutral and adaptive patterns of genetic differentiation (population-specific and pairwise FST) within five metapopulations (79 populations, 4583 individuals) of steelhead trout (Oncorhynchus mykiss) in the Columbia River Basin, USA. Using 151 putatively neutral and 29 candidate adaptive SNP loci, we found that climate-related variables (winter precipitation, summer maximum temperature, winter highest 5% flow events and summer mean flow) best explained neutral and adaptive patterns of genetic differentiation within metapopulations, suggesting that climatic variation likely influences both demography (neutral variation) and local adaptation (adaptive variation). However, we did not observe consistent relationships between climate variables and FST across all metapopulations, underscoring the need for replication when extrapolating results from one scale to another (e.g. basin-wide to the metapopulation scale). Sensitivity analysis (leave-one-population-out) revealed consistent relationships between climate variables and FST within three metapopulations; however, these patterns were not consistent in two metapopulations likely due to small sample sizes (N = 10). These results provide correlative evidence that climatic variation has shaped the genetic structure of steelhead populations and highlight the need for replication and sensitivity analyses in land and riverscape genetics.

  6. Contingency Contractor Optimization Phase 3 Sustainment Cost by JCA Implementation Guide

    Energy Technology Data Exchange (ETDEWEB)

    Durfee, Justin David [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Frazier, Christopher Rawls [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Arguello, Bryan [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Bandlow, Alisa [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Gearhart, Jared Lee [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Jones, Katherine A [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-05-01

    This document provides implementation guidance for implementing personnel group FTE costs by JCA Tier 1 or 2 categories in the Contingency Contractor Optimization Tool – Engineering Prototype (CCOT-P). CCOT-P currently only allows FTE costs by personnel group to differ by mission. Changes will need to be made to the user interface inputs pages and the database

  7. Best Spatiotemporal Performance Sustained by Optimal Number of Random Shortcuts on Complex Networks

    Institute of Scientific and Technical Information of China (English)

    WANG Mao-Sheng; HOU Zhong-Huai; XIN Hou-Wen

    2006-01-01

    @@ The spatial synchronization and temporal coherence of FitzHugh-Nagumo (FHN) neurons on complex networks are numerically investigated. When an optimal number of random shortcuts are added to a regular neural chain,the system can reach a state which is nearly periodic in time and almost synchronized in space.

  8. Dispersal-induced destabilization of metapopulations and oscillatory Turing patterns in ecological networks

    Science.gov (United States)

    Hata, Shigefumi; Nakao, Hiroya; Mikhailov, Alexander S.

    2014-01-01

    As shown by Alan Turing in 1952, differential diffusion may destabilize uniform distributions of reacting species and lead to emergence of patterns. While stationary Turing patterns are broadly known, the oscillatory instability, leading to traveling waves in continuous media and sometimes called the wave bifurcation, remains less investigated. Here, we extend the original analysis by Turing to networks and apply it to ecological metapopulations with dispersal connections between habitats. Remarkably, the oscillatory Turing instability does not lead to wave patterns in networks, but to spontaneous development of heterogeneous oscillations and possible extinction of species. We find such oscillatory instabilities for all possible food webs with three predator or prey species, under various assumptions about the mobility of individual species and nonlinear interactions between them. Hence, the oscillatory Turing instability should be generic and must play a fundamental role in metapopulation dynamics, providing a common mechanism for dispersal-induced destabilization of ecosystems.

  9. Rising relative fluctuation as a warning indicator of discontinuous transitions in symbiotic metapopulations

    Science.gov (United States)

    Lumi, Neeme; Laas, Katrin; Mankin, Romi

    2015-11-01

    The long-time limit behavior of the stochastic Lotka-Volterra model of a symbiotic metapopulation subjected to generalized Verhulst self-regulation is considered. The influence of a time-variable environment on the carrying capacities of subpopulations is modeled as a periodic deterministic part and a symmetric dichotomous noise. Relying on the mean-field approach it is established that at certain parameter regimes the mean field (average subpopulations size) exhibits hysteresis in respect to the noise correlation time, manifested in the appearance of colored-noise-induced discontinuous transitions. Especially, it is shown that the relative fluctuation of the subpopulation sizes exhibits accelerated increase prior to abrupt transitions of the metapopulation state. Moreover, in certain cases the autocorrelation function of the population sizes demonstrates anticorrelation at some values of the lag time.

  10. Selection of the optimal model of integrated sustainable management system in the mining companies

    OpenAIRE

    Miletić, Slavica; Bogdanović, Dejan; Paunković, Jane

    2015-01-01

    The multi-criteria analysis for the selection of the optimal model of integrated management system was conducted in this paper in order to improve the performance of mining companies. Integrated management system is the process of integrating of different management systems in a contemporary business as a requirement for each company in order to survive in the market. Modern companies that have implemented integrated management system work better, have arranged processes, improve its structur...

  11. A generic methodology for the design of sustainable carbon dioxide utilization processes using superstructure optimization

    DEFF Research Database (Denmark)

    Frauzem, Rebecca; Gani, Rafiqul

    ) is the primary greenhouse gas that is targeted via carbon capture and storage (CCS) as well as carbon capture and utilization (CCU) [1]. Carbon capture and utilization is showing promise because, in contrast with carbon capture and storage, it takes the captured carbon dioxide and makes further use of it......Global warming and other environmental concerns are fueling increased focus on sustainability resulting in new and stringent guidelines, especially with regard to emissions [1]. Greenhouse gases are prevalent and among harmful emissions that are targeted to be reduced; carbon dioxide (CO2......, including as an extractive agent or raw material. Chemical conversion, an important element of utilization, involves the use of carbon dioxide as a reactant in the production of chemical compounds [2]. However, for feasible implementation, a systematic methodology is needed for the design of the utilization...

  12. Optimal observability of sustained stochastic competitive inhibition oscillations at organellar volumes.

    Science.gov (United States)

    Davis, Kevin L; Roussel, Marc R

    2006-01-01

    When molecules are present in small numbers, such as is frequently the case in cells, the usual assumptions leading to differential rate equations are invalid and it is necessary to use a stochastic description which takes into account the randomness of reactive encounters in solution. We display a very simple biochemical model, ordinary competitive inhibition with substrate inflow, which is only capable of damped oscillations in the deterministic mass-action rate equation limit, but which displays sustained oscillations in stochastic simulations. We define an observability parameter, which is essentially just the ratio of the amplitude of the oscillations to the mean value of the concentration. A maximum in the observability is seen as the volume is varied, a phenomenon we name system-size observability resonance by analogy with other types of stochastic resonance. For the parameters of this study, the maximum in the observability occurs at volumes similar to those of bacterial cells or of eukaryotic organelles.

  13. Linear Economy Versus Circular Economy: A Comparative and Analyzer Study for Optimization of Economy for Sustainability

    Directory of Open Access Journals (Sweden)

    Sariatli Furkan

    2017-05-01

    Full Text Available Upon visiting the existing literature on the subject of linear vs. circular economy, this paper finds that, the blueprint of the current economy is hardly sustainable by using the comparative benchmarking method that drained from literature. The intrinsic mechanics of the linear economy, by relying on the wasteful take - make - dispose flow, is detrimental to the environment, cannot supply the growing populace of our planet with essential services and it naturally leads to strained profitability. Elements of a plausible solution to the challenges have been around for decades, although they have only recently been compiled in to the conceptual framework of circular economy. The core ideas of Circular Economy are elimination of waste by design, respect for the social, economic and natural environment and resource-conscious business conduct. Built on the backbone of these principles, the circular economy has demonstrated to deliver tangible benefits and viability to address the economic, environmental and social challenges of our days.

  14. Metapopulation dynamics of the mistletoe and its host in savanna areas with different fire occurrence.

    Directory of Open Access Journals (Sweden)

    Grazielle Sales Teodoro

    Full Text Available Mistletoes are aerial hemiparasitic plants which occupy patches of favorable habitat (host trees surrounded by unfavorable habitat and may be possibly modeled as a metapopulation. A metapopulation is defined as a subdivided population that persists due to the balance between colonization and extinction in discrete habitat patches. Our aim was to evaluate the dynamics of the mistletoe Psittacanthus robustus and its host Vochysia thyrsoidea in three Brazilian savanna areas using a metapopulation approach. We also evaluated how the differences in terms of fire occurrence affected the dynamic of those populations (two areas burned during the study and one was fire protected. We monitored the populations at six-month intervals. P. robustus population structure and dynamics met the expected criteria for a metapopulation: i the suitable habitats for the mistletoe occur in discrete patches; (ii local populations went extinct during the study and (iii colonization of previously non-occupied patches occurred. The ratio of occupied patches decreased in all areas with time. Local mistletoe populations went extinct due to two different causes: patch extinction in area with no fire and fire killing in the burned areas. In a burned area, the largest decrease of occupied patch ratios occurred due to a fire event that killed the parasites without, however, killing the host trees. The greatest mortality of V. thyrsoidea occurred in the area without fire. In this area, all the dead trees supported mistletoe individuals and no mortality was observed for parasite-free trees. Because P. robustus is a fire sensitive species and V. thyrsoidea is fire tolerant, P. robustus seems to increase host mortality, but its effect is lessened by periodic burning that reduces the parasite loads.

  15. Human-facilitated metapopulation dynamics in an emerging pest species, Cimex lectularius.

    Science.gov (United States)

    Fountain, Toby; Duvaux, Ludovic; Horsburgh, Gavin; Reinhardt, Klaus; Butlin, Roger K

    2014-03-01

    The number and demographic history of colonists can have dramatic consequences for the way in which genetic diversity is distributed and maintained in a metapopulation. The bed bug (Cimex lectularius) is a re-emerging pest species whose close association with humans has led to frequent local extinction and colonization, that is, to metapopulation dynamics. Pest control limits the lifespan of subpopulations, causing frequent local extinctions, and human-facilitated dispersal allows the colonization of empty patches. Founder events often result in drastic reductions in diversity and an increased influence of genetic drift. Coupled with restricted migration, this can lead to rapid population differentiation. We therefore predicted strong population structuring. Here, using 21 newly characterized microsatellite markers and approximate Bayesian computation (ABC), we investigate simplified versions of two classical models of metapopulation dynamics, in a coalescent framework, to estimate the number and genetic composition of founders in the common bed bug. We found very limited diversity within infestations but high degrees of structuring across the city of London, with extreme levels of genetic differentiation between infestations (FST  = 0.59). ABC results suggest a common origin of all founders of a given subpopulation and that the numbers of colonists were low, implying that even a single mated female is enough to found a new infestation successfully. These patterns of colonization are close to the predictions of the propagule pool model, where all founders originate from the same parental infestation. These results show that aspects of metapopulation dynamics can be captured in simple models and provide insights that are valuable for the future targeted control of bed bug infestations.

  16. Analysis and Optimization of Power Supply Structure Based on Markov Chain and Error Optimization for Renewable Energy from the Perspective of Sustainability

    Directory of Open Access Journals (Sweden)

    Xiaomin Xu

    2016-07-01

    Full Text Available With the rapid development of renewable energy, power supply structure is changing. However, thermal power is still dominant. With the background in low carbon economy, reasonable adjustment and optimization of the power supply structure is the trend of future development in the power industry. It is also a reliable guarantee of a fast, healthy and stable development of national economy. In this paper, the sustainable development of renewable energy sources is analyzed from the perspective of power supply. Through the research on the development of power supply structure, we find that regional power supply structure development mode conforms to dynamic characteristics and there must exist a Markov chain in the final equilibrium state. Combined with the characteristics of no aftereffect and small samples, this paper applies a Markov model to the power supply structure prediction. The optimization model is established to ensure that the model can fit the historical data as much as possible. Taking actual data of a certain area of Ningxia Province as an example, the models proposed in this paper are applied to the practice and results verify the validity and robustness of the model, which can provide decision basis for enterprise managers.

  17. Seeking urbanization security and sustainability: Multi-objective optimization of rainwater harvesting systems in China

    Science.gov (United States)

    Li, Yi; Ye, Quanliang; Liu, An; Meng, Fangang; Zhang, Wenlong; Xiong, Wei; Wang, Peifang; Wang, Chao

    2017-07-01

    Urban rainwater management need to achieve an optimal compromise among water resource augmentation, water loggings alleviation, economic investment and pollutants reduction. Rainwater harvesting (RWH) systems, such as green rooftops, porous pavements, and green lands, have been successfully implemented as viable approaches to alleviate water-logging disasters and water scarcity problems caused by rapid urbanization. However, there is limited guidance to determine the construction areas of RWH systems, especially for stormwater runoff control due to increasing extreme precipitation. This study firstly developed a multi-objective model to optimize the construction areas of green rooftops, porous pavements and green lands, considering the trade-offs among 24 h-interval RWH volume, stormwater runoff volume control ratio (R), economic cost, and rainfall runoff pollutant reduction. Pareto fronts of RWH system areas for 31 provinces of China were obtained through nondominated sorting genetic algorithm. On the national level, the control strategies for the construction rate (the ratio between the area of single RWH system and the total areas of RWH systems) of green rooftops (ηGR), porous pavements (ηPP) and green lands (ηGL) were 12%, 26% and 62%, and the corresponding RWH volume and total suspended solids reduction was 14.84 billion m3 and 228.19 kilotons, respectively. Optimal ηGR , ηPP and ηGL in different regions varied from 1 to 33%, 6 to 54%, and 30 to 89%, respectively. Particularly, green lands were the most important RWH system in 25 provinces with ηGL more than 50%, ηGR mainly less than 15%, and ηPP mainly between 10 and 30%. Results also indicated whether considering the objective MaxR made a non-significant difference for RWH system areas whereas exerted a great influence on the result of stormwater runoff control. Maximum daily rainfall under control increased, exceeding 200% after the construction of the optimal RWH system compared with that before

  18. Forest corridors maintain historical gene flow in a tiger metapopulation in the highlands of central India.

    Science.gov (United States)

    Sharma, Sandeep; Dutta, Trishna; Maldonado, Jesús E; Wood, Thomas C; Panwar, Hemendra Singh; Seidensticker, John

    2013-09-22

    Understanding the patterns of gene flow of an endangered species metapopulation occupying a fragmented habitat is crucial for landscape-level conservation planning and devising effective conservation strategies. Tigers (Panthera tigris) are globally endangered and their populations are highly fragmented and exist in a few isolated metapopulations across their range. We used multi-locus genotypic data from 273 individual tigers (Panthera tigris tigris) from four tiger populations of the Satpura-Maikal landscape of central India to determine whether the corridors in this landscape are functional. This 45 000 km(2) landscape contains 17% of India's tiger population and 12% of its tiger habitat. We applied Bayesian and coalescent-based analyses to estimate contemporary and historical gene flow among these populations and to infer their evolutionary history. We found that the tiger metapopulation in central India has high rates of historical and contemporary gene flow. The tests for population history reveal that tigers populated central India about 10 000 years ago. Their population subdivision began about 1000 years ago and accelerated about 200 years ago owing to habitat fragmentation, leading to four spatially separated populations. These four populations have been in migration-drift equilibrium maintained by high gene flow. We found the highest rates of contemporary gene flow in populations that are connected by forest corridors. This information is highly relevant to conservation practitioners and policy makers, because deforestation, road widening and mining are imminent threats to these corridors.

  19. Hiding in Plain Sight: A Case for Cryptic Metapopulations in Brook Trout (Salvelinus fontinalis.

    Directory of Open Access Journals (Sweden)

    David C Kazyak

    Full Text Available A fundamental issue in the management and conservation of biodiversity is how to define a population. Spatially contiguous fish occupying a stream network have often been considered to represent a single, homogenous population. However, they may also represent multiple discrete populations, a single population with genetic isolation-by-distance, or a metapopulation. We used microsatellite DNA and a large-scale mark-recapture study to assess population structure in a spatially contiguous sample of Brook Trout (Salvelinus fontinalis, a species of conservation concern. We found evidence for limited genetic exchange across small spatial scales and in the absence of barriers to physical movement. Mark-recapture and stationary passive integrated transponder antenna records demonstrated that fish from two tributaries very seldom moved into the opposite tributary, but movements between the tributaries and mainstem were more common. Using Bayesian genetic clustering, we identified two genetic groups that exhibited significantly different growth rates over three years of study, yet survival rates were very similar. Our study highlights the importance of considering the possibility of multiple genetically distinct populations occurring within spatially contiguous habitats, and suggests the existence of a cryptic metapopulation: a spatially continuous distribution of organisms exhibiting metapopulation-like behaviors.

  20. Structural complexity, movement bias, and metapopulation extinction risk in dendritic ecological networks

    Science.gov (United States)

    Campbell Grant, Evan H.

    2011-01-01

    Spatial complexity in metacommunities can be separated into 3 main components: size (i.e., number of habitat patches), spatial arrangement of habitat patches (network topology), and diversity of habitat patch types. Much attention has been paid to lattice-type networks, such as patch-based metapopulations, but interest in understanding ecological networks of alternative geometries is building. Dendritic ecological networks (DENs) include some increasingly threatened ecological systems, such as caves and streams. The restrictive architecture of dendritic ecological networks might have overriding implications for species persistence. I used a modeling approach to investigate how number and spatial arrangement of habitat patches influence metapopulation extinction risk in 2 DENs of different size and topology. Metapopulation persistence was higher in larger networks, but this relationship was mediated by network topology and the dispersal pathways used to navigate the network. Larger networks, especially those with greater topological complexity, generally had lower extinction risk than smaller and less-complex networks, but dispersal bias and magnitude affected the shape of this relationship. Applying these general results to real systems will require empirical data on the movement behavior of organisms and will improve our understanding of the implications of network complexity on population and community patterns and processes.

  1. Multi-state models: metapopulation and life history analyses

    Directory of Open Access Journals (Sweden)

    Arnason, A. N.

    2004-06-01

    state ambiguity (dormant or dead? and can permit assessing the influence of environmental covariates on this proportion. The presentation by Christophe Barbraud (Barbraud & Weimerskirk, 2004, included in these proceedings as an extended abstract, takes the life–history trade–off application of MSMR models a step further by taking into account environmental and individual covariates on survival. The trade–off considered is between survival and transitions among several states describing breeding experience of long–lived petrels and how it is affected by harsh climate conditions. The study is a showcase for the powers of the new software (U–Care and M–Surge. The paper by Senar and Conroy (Senar & Conroy, 2004 is a novel application of MSMR models to animal epidemiology. States included age, sex and infected state and the model permits estimation of survival, infection, and recovery rates for birds during an outbreak of Serin avian pox. The use of a MSMR model permits estimation of the prevalence rate unconfounded by differences in capture rates of infected and non–infected birds. Here too there is a potential for ambiguous states in that the uninfected state might include both immune post–infection animals and susceptible pre–infection animals and these groups would likely have different survival rates. The authors are able to deal with this because of the length of the study and the availability of data outside the main outbreak. Finally, this session includes a paper by Jamieson and Brooks (Jamieson & Brooks, 2004 that appears to lie outside the MSMR theme of this session but which was included because of its relevanceto metapopulation analyses. Our call for papers for this session also invited papers illustrating multi– population meta–analysis and use of Bayesian methods. By these criteria, their paper is no outlier. It addresses the longstanding question of density dependence in game bird survival; a question of great interest to theoretical

  2. Comparing large-scale computational approaches to epidemic modeling: Agent-based versus structured metapopulation models

    Directory of Open Access Journals (Sweden)

    Merler Stefano

    2010-06-01

    Full Text Available Abstract Background In recent years large-scale computational models for the realistic simulation of epidemic outbreaks have been used with increased frequency. Methodologies adapt to the scale of interest and range from very detailed agent-based models to spatially-structured metapopulation models. One major issue thus concerns to what extent the geotemporal spreading pattern found by different modeling approaches may differ and depend on the different approximations and assumptions used. Methods We provide for the first time a side-by-side comparison of the results obtained with a stochastic agent-based model and a structured metapopulation stochastic model for the progression of a baseline pandemic event in Italy, a large and geographically heterogeneous European country. The agent-based model is based on the explicit representation of the Italian population through highly detailed data on the socio-demographic structure. The metapopulation simulations use the GLobal Epidemic and Mobility (GLEaM model, based on high-resolution census data worldwide, and integrating airline travel flow data with short-range human mobility patterns at the global scale. The model also considers age structure data for Italy. GLEaM and the agent-based models are synchronized in their initial conditions by using the same disease parameterization, and by defining the same importation of infected cases from international travels. Results The results obtained show that both models provide epidemic patterns that are in very good agreement at the granularity levels accessible by both approaches, with differences in peak timing on the order of a few days. The relative difference of the epidemic size depends on the basic reproductive ratio, R0, and on the fact that the metapopulation model consistently yields a larger incidence than the agent-based model, as expected due to the differences in the structure in the intra-population contact pattern of the approaches. The age

  3. Robust optimization on sustainable biodiesel supply chain produced from waste cooking oil under price uncertainty.

    Science.gov (United States)

    Zhang, Yong; Jiang, Yunjian

    2017-02-01

    Waste cooking oil (WCO)-for-biodiesel conversion is regarded as the "waste-to-wealthy" industry. This paper addresses the design of a WCO-for-biodiesel supply chain at both strategic and tactical levels. The supply chain of this problem is studied, which is based on a typical mode of the waste collection (from restaurants' kitchen) and conversion in the cities. The supply chain comprises three stakeholders: WCO supplier, integrated bio-refinery and demand zone. Three key problems should be addressed for the optimal design of the supply chain: (1) the number, sizes and locations of bio-refinery; (2) the sites and amount of WCO collected; (3) the transportation plans of WCO and biodiesel. A robust mixed integer linear model with muti-objective (economic, environmental and social objectives) is proposed for these problems. Finally, a large-scale practical case study is adopted based on Suzhou, a city in the east of China, to verify the proposed models.

  4. A Cost Optimized Fully Sustainable Power System for Southeast Asia and the Pacific Rim

    Directory of Open Access Journals (Sweden)

    Ashish Gulagi

    2017-04-01

    Full Text Available In this paper, a cost optimal 100% renewable energy based system is obtained for Southeast Asia and the Pacific Rim region for the year 2030 on an hourly resolution for the whole year. For the optimization, the region was divided into 15 sub-regions and three different scenarios were set up based on the level of high voltage direct current grid connections. The results obtained for a total system levelized cost of electricity showed a decrease from 66.7 €/MWh in a decentralized scenario to 63.5 €/MWh for a centralized grid connected scenario. An integrated scenario was simulated to show the benefit of integrating additional demand of industrial gas and desalinated water which provided the system the required flexibility and increased the efficiency of the usage of storage technologies. This was reflected in the decrease of system cost by 9.5% and the total electricity generation by 5.1%. According to the results, grid integration on a larger scale decreases the total system cost and levelized cost of electricity by reducing the need for storage technologies due to seasonal variations in weather and demand profiles. The intermittency of renewable technologies can be effectively stabilized to satisfy hourly demand at a low cost level. A 100% renewable energy based system could be a reality economically and technically in Southeast Asia and the Pacific Rim with the cost assumptions used in this research and it may be more cost competitive than the nuclear and fossil carbon capture and storage (CCS alternatives.

  5. Optimizing the European regulatory framework for sustainable bacteriophage therapy in human medicine.

    Science.gov (United States)

    Verbeken, Gilbert; Pirnay, Jean-Paul; De Vos, Daniel; Jennes, Serge; Zizi, Martin; Lavigne, Rob; Casteels, Minne; Huys, Isabelle

    2012-06-01

    For practitioners at hospitals seeking to use natural (not genetically modified, as appearing in nature) bacteriophages for treatment of antibiotic-resistant bacterial infections (bacteriophage therapy), Europe's current regulatory framework for medicinal products hinders more than it facilitates. Although many experts consider bacteriophage therapy to be a promising complementary (or alternative) treatment to antibiotic therapy, no bacteriophage-specific framework for documentation exists to date. Decades worth of historical clinical data on bacteriophage therapy (from Eastern Europe, particularly Poland, and the former Soviet republics, particularly Georgia and Russia, as well as from today's 27 EU member states and the US) have not been taken into account by European regulators because these data have not been validated under current Western regulatory standards. Consequently, applicants carrying out standard clinical trials on bacteriophages in Europe are obliged to initiate clinical work from scratch. This paper argues for a reduced documentation threshold for Phase 1 clinical trials of bacteriophages and maintains that bacteriophages should not be categorized as classical medicinal products for at least two reasons: (1) such a categorization is scientifically inappropriate for this specific therapy and (2) such a categorization limits the marketing authorization process to industry, the only stakeholder with sufficient financial resources to prepare a complete dossier for the competent authorities. This paper reflects on the current regulatory framework for medicines in Europe and assesses possible regulatory pathways for the (re-)introduction of bacteriophage therapy in a way that maintains its effectiveness and safety as well as its inherent characteristics of sustainability and in situ self-amplification and limitation.

  6. High fidelity nuclear energy system optimization towards an environmentally benign, sustainable, and secure energy source.

    Energy Technology Data Exchange (ETDEWEB)

    Tsvetkov, Pavel Valeryevich (Texas A& M University, College Station, TX); Rodriguez, Salvador B.; Ames, David E., II (Texas A& M University, College Station, TX); Rochau, Gary Eugene

    2009-09-01

    The impact associated with energy generation and utilization is immeasurable due to the immense, widespread, and myriad effects it has on the world and its inhabitants. The polar extremes are demonstrated on the one hand, by the high quality of life enjoyed by individuals with access to abundant reliable energy sources, and on the other hand by the global-scale environmental degradation attributed to the affects of energy production and use. Thus, nations strive to increase their energy generation, but are faced with the challenge of doing so with a minimal impact on the environment and in a manner that is self-reliant. Consequently, a revival of interest in nuclear energy has followed, with much focus placed on technologies for transmuting nuclear spent fuel. The performed research investigates nuclear energy systems that optimize the destruction of nuclear waste. In the context of this effort, nuclear energy system is defined as a configuration of nuclear reactors and corresponding fuel cycle components. The proposed system has unique characteristics that set it apart from other systems. Most notably the dedicated High-Energy External Source Transmuter (HEST), which is envisioned as an advanced incinerator used in combination with thermal reactors. The system is configured for examining environmentally benign fuel cycle options by focusing on minimization or elimination of high level waste inventories. Detailed high-fidelity exact-geometry models were developed for representative reactor configurations. They were used in preliminary calculations with Monte Carlo N-Particle eXtented (MCNPX) and Standardized Computer Analysis for Licensing Evaluation (SCALE) code systems. The reactor models have been benchmarked against existing experimental data and design data. Simulink{reg_sign}, an extension of MATLAB{reg_sign}, is envisioned as the interface environment for constructing the nuclear energy system model by linking the individual reactor and fuel component sub

  7. Combining Interactive Infrastructure Modeling and Evolutionary Algorithm Optimization for Sustainable Water Resources Design

    Science.gov (United States)

    Smith, R.; Kasprzyk, J. R.; Zagona, E. A.

    2013-12-01

    Population growth and climate change, combined with difficulties in building new infrastructure, motivate portfolio-based solutions to ensuring sufficient water supply. Powerful simulation models with graphical user interfaces (GUI) are often used to evaluate infrastructure portfolios; these GUI based models require manual modification of the system parameters, such as reservoir operation rules, water transfer schemes, or system capacities. Multiobjective evolutionary algorithm (MOEA) based optimization can be employed to balance multiple objectives and automatically suggest designs for infrastructure systems, but MOEA based decision support typically uses a fixed problem formulation (i.e., a single set of objectives, decisions, and constraints). This presentation suggests a dynamic framework for linking GUI-based infrastructure models with MOEA search. The framework begins with an initial formulation which is solved using a MOEA. Then, stakeholders can interact with candidate solutions, viewing their properties in the GUI model. This is followed by changes in the formulation which represent users' evolving understanding of exigent system properties. Our case study is built using RiverWare, an object-oriented, data-centered model that facilitates the representation of a diverse array of water resources systems. Results suggest that assumptions within the initial MOEA search are violated after investigating tradeoffs and reveal how formulations should be modified to better capture stakeholders' preferences.

  8. Optimization of a Groundwater Monitoring Network for a Sustainable Development of the Maheshwaram Catchment, India

    Directory of Open Access Journals (Sweden)

    Shakeel Ahmed

    2011-02-01

    Full Text Available Groundwater is one of the most valuable resources for drinking water and irrigation in the Maheshwaram Catchment, Central India, where most of the local population depends on it for agricultural activities. An increasing demand for irrigation and the growing concern about potential water contamination makes imperative the implementation of a systematic groundwater-quality monitoring program in the region. Nonetheless, limited funding and resources emphasize the need to achieve a representative but cost-effective sampling strategy. In this context, field observations were combined with a geostatistical analysis to define an optimized monitoring network able to provide sufficient and non-redundant information on key hydrochemical parameters. A factor analysis was used to evaluate the interrelationship among variables, and permitted to reduce the original dataset into a new configuration of monitoring points still able to capture the spatial variability in the groundwater quality of the basin. The approach is useful to maximize data collection and contributes to better manage the allocation of resources under budget constrains.

  9. High fidelity nuclear energy system optimization towards an environmentally benign, sustainable, and secure energy source.

    Energy Technology Data Exchange (ETDEWEB)

    Tsvetkov, Pavel Valeryevich (Texas A& M University, College Station, TX); Rodriguez, Salvador B.; Ames, David E., II (Texas A& M University, College Station, TX); Rochau, Gary Eugene

    2010-10-01

    A new high-fidelity integrated system method and analysis approach was developed and implemented for consistent and comprehensive evaluations of advanced fuel cycles leading to minimized Transuranic (TRU) inventories. The method has been implemented in a developed code system integrating capabilities of Monte Carlo N - Particle Extended (MCNPX) for high-fidelity fuel cycle component simulations. In this report, a Nuclear Energy System (NES) configuration was developed to take advantage of used fuel recycling and transmutation capabilities in waste management scenarios leading to minimized TRU waste inventories, long-term activities, and radiotoxicities. The reactor systems and fuel cycle components that make up the NES were selected for their ability to perform in tandem to produce clean, safe, and dependable energy in an environmentally conscious manner. The diversity in performance and spectral characteristics were used to enhance TRU waste elimination while efficiently utilizing uranium resources and providing an abundant energy source. A computational modeling approach was developed for integrating the individual models of the NES. A general approach was utilized allowing for the Integrated System Model (ISM) to be modified in order to provide simulation for other systems with similar attributes. By utilizing this approach, the ISM is capable of performing system evaluations under many different design parameter options. Additionally, the predictive capabilities of the ISM and its computational time efficiency allow for system sensitivity/uncertainty analysis and the implementation of optimization techniques.

  10. Sustainable Industrial Product Systems. Integration of Life Cycle Assessment in Product development and Optimization of Product Systems

    Energy Technology Data Exchange (ETDEWEB)

    Hanssen, Ole Joergen

    1997-12-31

    This thesis contributes to the development and testing of environmental life cycle assessment (LCA) in product development and management in industry. It is based on systems theory and systems engineering. It develops a method for sustainable product development that has been successfully tested in the Nordic project called NEP. The LCA method is also a basis for an optimization model, where life cycle economy and environmental impacts from product systems are optimized with a non-linear model. A more complete mathematical model for LCA, based on the functional requirements on a product system, is also developed. The statistical properties of emission factors are studied using a data set from the Swedish Kraft Mill industry. It is shown that emission factors may be assumed constants in the LCA model, but with rather large variations within a population of Kraft mills. It is shown that there are a few environmental impacts which are important for most types of products under Scandinavian conditions, especially global warming potential, acidification, human toxicity and fossil energy depletion. There are significant differences between the contribution to these impacts from different life cycle stages, where raw material processing and use of products are generally more important than the other stages. Test cases indicate that there are no large conflicts between improvements in environmental impacts and customer requirements. Environmental improvements seem to increase purchase cost of products in some cases, but the life cycle cost of the products seem in most cases to be reduced. It is concluded that there are opportunities for 30-50% improvements in product system, based on relatively simple modifications of the systems. 246 refs., 63 figs., 19 tabs.

  11. Advances in studies on metapopulation dynamics%复合种群动态研究进展

    Institute of Scientific and Technical Information of China (English)

    黄世能; 王伯荪

    2001-01-01

    复合种群动态研究是当今保护生物学和生态学中最热门的课题之一。在此较为详细地介绍了复合种群动态的有关概念和术语、经验研究和理论探索的最新进展以及相关的预测模型,对我国开展相关研究有参考价值。%Study of metapopulation dynamics is one of the most important subjects in modern conservation biology and ecology. In this paper, the key metapopulation terms, advances in empirical and theoretical approaches and predictive models in relation to metapopulation dynamics as well as their implications for biological conser vation practices were outlined.

  12. Effects of city-size heterogeneity on epidemic spreading in a metapopulation: A reaction-diffusion approach

    CERN Document Server

    Lund, Halvor; Simonsen, Ingve

    2012-01-01

    We review and introduce a generalized reaction-diffusion approach to epidemic spreading in a metapopulation modeled as a complex network. The metapopulation consists of susceptible and infected individuals that are grouped in subpopulations symbolising cities and villages that are coupled by human travel in a transportation network. By analytic methods and numerical simulations we calculate the fraction of infected people in the metaopoluation in the long time limit, as well as the relevant parameters characterising the epidemic threshold that separates an epidemic from a non-epidemic phase. Within this model, we investigate the effect of a heterogeneous network topology and a heterogeneous subpopulation size distribution. Such a system is suited for epidemic modeling where small villages and big cities exist simultaneously in the metapopulation. We find that the heterogeneous conditions cause the epidemic threshold to be a non-trivial function of the reaction rates (local parameters), the network's topology ...

  13. Metapopulation modelling of riparian tree species persistence in river networks under climate change.

    Science.gov (United States)

    Van Looy, Kris; Piffady, Jérémy

    2017-11-01

    Floodplain landscapes are highly fragmented by river regulation resulting in habitat degradation and flood regime perturbation, posing risks to population persistence. Climate change is expected to pose supplementary risks in this context of fragmented landscapes, and especially for river systems adaptation management programs are developed. The association of habitat quality and quantity with the landscape dynamics and resilience to human-induced disturbances is still poorly understood in the context of species survival and colonization processes, but essential to prioritize conservation and restoration actions. We present a modelling approach that elucidates network connectivity and landscape dynamics in spatial and temporal context to identify vital corridors and conservation priorities in the Loire river and its tributaries. Alteration of flooding and flow regimes is believed to be critical to population dynamics in river ecosystems. Still, little is known of critical levels of alteration both spatially and temporally. We applied metapopulation modelling approaches for a dispersal-limited tree species, white elm; and a recruitment-limited tree species, black poplar. In different model steps the connectivity and natural dynamics of the river landscape are confronted with physical alterations (dams/dykes) to species survival and then future scenarios for climatic changes and potential adaptation measures are entered in the model and translated in population persistence over the river basin. For the two tree species we highlighted crucial network zones in relation to habitat quality and connectivity. Where the human impact model already shows currently restricted metapopulation development, climate change is projected to aggravate this persistence perspective substantially. For both species a significant drawback to the basin population is observed, with 1/3 for elm and ¼ for poplar after 25 years already. But proposed adaptation measures prove effective to even

  14. Designing Sustainable Public Transportation: Integrated Optimization of Bus Speed and Holding Time in a Connected Vehicle Environment

    Directory of Open Access Journals (Sweden)

    Wei Wu

    2016-11-01

    Full Text Available Developing public transportation and giving priority to buses is a feasible solution for improving the level of public transportation service, which facilitates congestion alleviation and prevention, and contributes to urban development and city sustainability. This paper presents a novel bus operation control strategy including both holding control and speed control to improve the level of service of transit systems within a connected vehicle environment. Most previous work focuses on optimization of signal timing to decrease the bus signal delay by assuming that holding control is not applied; the speed of buses is given as a constant input and the acceleration and deceleration processes of buses can be neglected. This paper explores the benefits of a bus operation control strategy to minimize the total cost, which includes bus signal delay, bus holding delay, bus travel delay, acceleration cost due to frequent stops and intense driving. A set of formulations are developed to explicitly capture the interaction between bus holding control and speed control. Experimental analysisand simulation tests have shown that the proposed integrated operational model outperforms the traditional control, speed control only, or holding control only strategies in terms of reducing the total cost of buses. The sensitivity analysis has further demonstrated the potential effectiveness of the proposed approach to be applied in a real-time bus operation control system under different levels of traffic demand, bus stop locations, and speed limits.

  15. Decreasing Fertilizer use by Optimizing Plant-microbe Interactions for Sustainable Supply of Nitrogen for Bioenergy Crops

    Science.gov (United States)

    Schicklberger, M. F.; Huang, J.; Felix, P.; Pettenato, A.; Chakraborty, R.

    2013-12-01

    Nitrogen (N) is an essential component of DNA and proteins and consequently a key element of life. N often is limited in plants, affecting plant growth and productivity. To alleviate this problem, tremendous amounts of N-fertilizer is used, which comes at a high economic price and heavy energy demand. In addition, N-fertilizer also significantly contributes to rising atmospheric greenhouse gas concentrations. Therefore, the addition of fertilizer to overcome N limitation is highly undesirable. To explore reduction in fertilizer use our research focuses on optimizing the interaction between plants and diazotrophic bacteria, which could provide adequate amounts of N to the host-plant. Therefore we investigated the diversity of microbes associated with Tobacco (Nicotiana tabacum) and Switchgrass (Panicum virgatum), considered as potential energy crop for bioenergy production. Several bacterial isolates with representatives from Alphaproteobacteria, Gammaproteobacteria, Actinobacteria, Bacteriodetes and Bacilli were obtained from the roots, leaves, rhizoplane and rhizosphere of these plants. Majority of these isolates grew best with simple sugars and small organic acids. As shown by PCR amplification of nifH, several of these isolates are potential N2-fixing bacteria. We investigated diazotrophs for their response to elevated temperature and salinity (two common climate change induced stresses found on marginal lands), their N2-fixing ability, and their response to root exudates (which drive microbial colonization of the plant). Together this understanding is necessary for the development of eco-friendly, economically sustainable energy crops by decreasing their dependency on fertilizer.

  16. Optimal energy options under Clean Development Mechanism: Renewable energy projects for sustainable development and carbon emission reduction

    Science.gov (United States)

    Gilau, Asmerom M.

    This dissertation addresses two distinct objectives; designing cost-effective renewable energy powered projects including seawater reverse osmosis (SWRO), aquaculture, and ice-making plant, and analyzing the cost-effectiveness of these projects in achieving low abatement costs and promoting sustainable developments under the Clean Development Mechanism. The results of SWRO analysis show that a wind powered system is the least expensive and a PV powered system the most expensive, with finished water costs of about 0.50 /m3 and 1.00 /m3, respectively. By international standards, these costs are competitive. The results of renewable energy powered commercial tilapia production indicate that a wind-diesel system has high potential for intensive tilapia production as well as carbon dioxide emission reductions. The study also investigates aeration failures in renewable energy powered tilapia production systems. With respect to the ice-making plant, unlike previous studies which consider nighttime operation only, we have found that a nighttime PV powered ice-making system is more expensive (1/kWh) than daytime ice-making system (0.70/kWh). Our optimal energy options analysis at project scale which includes SWRO, ice-making plant and household energy consumption for about 100 households shows that compared to diesel only energy option, PV-D, W-D, and PV-W-D hybrids are very cost-effective energy options. Moreover, energy options with high levels of renewable energy including 100% renewables have the lowest net present cost and they are already cost-effective without CDM. On the other hand, while the removal of about 87% carbon dioxide emissions could be achieved at negative cost, initial investment could increase by a factor of 40, which is one of the primary barriers hindering wider renewable energy applications in developing countries. Thus in order to increase developing countries' participation in the carbon market, CDM policy should shift from a purely market oriented

  17. Linking local retention, self-recruitment, and persistence in marine metapopulations

    KAUST Repository

    Lett, Christophe

    2015-08-01

    Three indices of larval retention have been used in the literature to assess the tendency for self-maintenance of local marine populations: local retention (LR), self-recruitment (SR), and relative local retention (RLR). Only one of these, LR, defined as the ratio of locally produced settlement to local egg production, has a clear relationship to self-persistence of individual sites. However, SR, the ratio of locally produced settlement to settlement of all origins at a site, is generally easier to measure experimentally. We use theoretical, simulation, and empirical approaches to bridge the gap between these different indices, and demonstrate that there is a proportional relationship between SR and LR for metapopulations close to a stable state and with lifetime egg production (LEP) approximately uniform over space. Similarly, for systems where larval mortality rates are a relatively uniform function of release site, RLR (defined as the ratio of locally produced settlement to all settlement of local origin) and LR will also be proportional. Therefore, SR and RLR provide information on relative rates of LR for systems satisfying these conditions. Furthermore, the ratio between LR and SR can be used to evaluate global persistence of metapopulations, and therefore provides valuable information not necessarily available if only LR is considered.

  18. Supplementary Material for: Linking local retention, self-recruitment, and persistence in marine metapopulations

    KAUST Repository

    Lett, Christophe

    2016-01-01

    Three indices of larval retention have been used in the literature to assess the tendency for self-maintenance of local marine populations: local retention (LR), self-recruitment (SR), and relative local retention (RLR). Only one of these, LR, defined as the ratio of locally produced settlement to local egg production, has a clear relationship to self-persistence of individual sites. However, SR, the ratio of locally produced settlement to settlement of all origins at a site, is generally easier to measure experimentally. We use theoretical, simulation, and empirical approaches to bridge the gap between these different indices, and demonstrate that there is a proportional relationship between SR and LR for metapopulations close to a stable state and with lifetime egg production (LEP) approximately uniform over space. Similarly, for systems where larval mortality rates are a relatively uniform function of release site, RLR (defined as the ratio of locally produced settlement to all settlement of local origin) and LR will also be proportional. Therefore, SR and RLR provide information on relative rates of LR for systems satisfying these conditions. Furthermore, the ratio between LR and SR can be used to evaluate global persistence of metapopulations, and therefore provides valuable information not necessarily available if only LR is considered.

  19. The maintenance of genetic variation due to asymmetric gene flow in dendritic metapopulations.

    Science.gov (United States)

    Morrissey, Michael B; de Kerckhove, Derrick T

    2009-12-01

    Dendritic landscapes can have ecological properties that differ importantly from simpler spatial arrangements of habitats. Most dendritic landscapes are structured by elevation, and therefore, migration is likely to be directionally biased. While the population-genetic consequences of both dendritic landscape arrangements and asymmetric migration have begun to be studied, these processes have not been considered together. Simple conceptual models predict that if migration into branch (headwater) populations is limited, such populations can act as reservoirs for potentially unique alleles. As a consequence of the fact that dendritic landscapes have, by definition, more branches than internal habitat patches, this process may lead to the maintenance of higher overall genetic diversities in metapopulations inhabiting dendritic networks where migration is directionally biased. Here we begin to address the generality of these simple predictions using genetic models and a review of empirical literature. We show, for a range of demographic parameters, that dendritic systems with asymmetric migration can maintain levels of genetic variation that are very different, sometimes very elevated, compared with more classical models of geographical population structure. Furthermore, predicted patterns of genetic variation within metapopulations--that is, stepwise increases in genetic diversity at nodes--do occur in some empirical data.

  20. Hierarchical modeling and inference in ecology: The analysis of data from populations, metapopulations and communities

    Science.gov (United States)

    Royle, J. Andrew; Dorazio, Robert M.

    2008-01-01

    A guide to data collection, modeling and inference strategies for biological survey data using Bayesian and classical statistical methods. This book describes a general and flexible framework for modeling and inference in ecological systems based on hierarchical models, with a strict focus on the use of probability models and parametric inference. Hierarchical models represent a paradigm shift in the application of statistics to ecological inference problems because they combine explicit models of ecological system structure or dynamics with models of how ecological systems are observed. The principles of hierarchical modeling are developed and applied to problems in population, metapopulation, community, and metacommunity systems. The book provides the first synthetic treatment of many recent methodological advances in ecological modeling and unifies disparate methods and procedures. The authors apply principles of hierarchical modeling to ecological problems, including * occurrence or occupancy models for estimating species distribution * abundance models based on many sampling protocols, including distance sampling * capture-recapture models with individual effects * spatial capture-recapture models based on camera trapping and related methods * population and metapopulation dynamic models * models of biodiversity, community structure and dynamics.

  1. Gum Ghatti--a pharmaceutical excipient: development, evaluation and optimization of sustained release mucoadhesive matrix tablets of domperidone.

    Science.gov (United States)

    Gurpreetarora; Malik, Karan; Rana, Vikas; Singh, Inderbir

    2012-01-01

    The objective of this study was to extend the GI residence time of the dosage form and to control the release of domperidone using directly compressible sustained release mucoadhesive matrix (SRMM) tablets. A 2-factor centre composite design (CCD) was employed to study the influence of independent variables like gum ghatti (GG) (X1) and hydroxylpropylmethyl cellulose K 15M (HPMC K 15M) (X2) on dependent variable like mucoadhesive strength, tensile strength, release exponent (n), t50 (time for 50% drug release), rel(10 h) (release after 10 h) and rel(18 h) (release after 18 h). Tablets were prepared by direct compression technology and evaluated for tablet parametric test (drug assay, diameter, thickness, hardness and tensile strength), mucoadhesive strength (using texture analyzer) and in vitro drug release studies. The tensile strength and mucoadhesive strength were found to be increased from 0.665 +/- 0.1 to 1.591 +/- 0.1 MN/cm2 (Z1 to Z9) and 10.789 +/- 0.985 to 50.924 +/- 1.150 N (Z1 to Z9), respectively. The release kinetics follows first order and Hixson Crowell equation indicating drug release following combination of diffusion and erosion. The n varies between 0.834 and 1.273, indicating release mechanism shifts from non fickian (anomalous release) to super case II, which depict that drug follows multiple drug release mechanism. The t50 time was found to increase from 5 +/- 0.12 to 11.4 +/- 0.14 h (Z1 to Z9) and release after 10 and 18 h decreases with increasing concentration of both polymers concluding with release controlling potential of polymers. The accelerated stability studies were performed on optimized formulation as per ICH guideline and the result showed that there was no significant change in tensile strength, mucoadhesive strength and drug assay.

  2. Size of the California Brown Pelican Metapopulation During a Non-El Nino Year

    Science.gov (United States)

    Anderson, Daniel W.; Henny, Charles J.; Godinez-Reyes, Carlos; Gress, Franklin; Palacios, Eduardo L.; Santos del Prado, Karina; Bredy, James

    2007-01-01

    Overall, we estimated a total metapopulation within the geographical range of the California brown pelican subspecies (Pelecanus occidentalis californicus) as about 70,680 ? 2,640 breeding pairs (mean ? SD). Little change in at least three decades is indicated in the total metapopulation south of the Southern California Bight (SCB) subpopulation, but significant improvements in the breeding subpopulation size in the SCB reported elsewhere, support the present high numbers observed in this northernmost subpopulation. The largest breeding aggregation within the entire range (consisting of three immediately adjacent sub-colonies), at the San Lorenzo Archipelago, consisted of about 17,225 breeding pairs, or about 24.4% of the metapopulation in 2006. Other, smaller colonies are no less important, however, although each subpopulation defined by us seemed to have a single or small number of large 'core' breeding colonies, plus many smaller colonies (for example, in 2006, one colony consisted of only 2 breeding pairs). Small colonies (< about 70 nests) comprised about 35.6% of the total occupied colonies, but only about 0.87% of the total estimated numbers (values corrected for detectability). The modal colony-size throughout the range was much smaller (about 230 to 1,300 breeding pairs, depending on subpopulation), indicating that small, scattered colonies and sub-colonies, especially on the range peripheries, function in brown pelican population dynamics and are no less important from a conservation viewpoint. These smaller breeding colonies probably represent some colonies of antiquity, but also range expansions and contractions that occur within the typically-defined metapopulation, and local manifestations of source-sink phenomena. Given such dynamics, even unoccupied islands within the range in 2006 have conservation importance from the viewpoint of such dynamics as potential alternate nesting sites. Natural variations in the estimated population levels seem to be

  3. Optimization of the close-to-carrier Phase Noise in a CMOS-MEMS oscillator using a Phase Tunable Sustaining-Amplifier.

    Science.gov (United States)

    Sobreviela, Guillermo; Riverola, Martin; Canals, Francesc; Del Monte, Arantxa; Beumala, Nuria

    2017-02-13

    In this paper, the phase noise of a 24-MHz CMOSMEMS oscillator with zero-level vacuum package is studied. We characterize and analyze the nonlinear regime of each one of the modules that compose the oscillator (CMOS sustaining-amplifier and MEMS resonator). As we show, the presented resonator exhibits a high nonlinear behavior. Such fact is exploited as a mechanism to stabilize the oscillation amplitude, allowing to maintain the sustaining-amplifier working in the linear regime. Consequently, the nonlinear resonator becomes the main closeto- carrier phase noise source. The sustaining amplifier, which functions as a phase shifter, was developed such that MEMS operation point optimization could be achieved without an increase in circuitry modules. Therefore, the system saves on area and power, and is able to improve the phase noise 26 dBc/Hz (@1 kHz carrier frequency offset).

  4. The watershed-scale optimized and rearranged landscape design (WORLD) model and local biomass processing depots for sustainable biofuel production: Integrated life cycle assessments

    Energy Technology Data Exchange (ETDEWEB)

    Eranki, Pragnya L.; Manowitz, David H.; Bals, Bryan D.; Izaurralde, Roberto C.; Kim, Seungdo; Dale, Bruce E.

    2013-07-23

    An array of feedstock is being evaluated as potential raw material for cellulosic biofuel production. Thorough assessments are required in regional landscape settings before these feedstocks can be cultivated and sustainable management practices can be implemented. On the processing side, a potential solution to the logistical challenges of large biorefi neries is provided by a network of distributed processing facilities called local biomass processing depots. A large-scale cellulosic ethanol industry is likely to emerge soon in the United States. We have the opportunity to influence the sustainability of this emerging industry. The watershed-scale optimized and rearranged landscape design (WORLD) model estimates land allocations for different cellulosic feedstocks at biorefinery scale without displacing current animal nutrition requirements. This model also incorporates a network of the aforementioned depots. An integrated life cycle assessment is then conducted over the unified system of optimized feedstock production, processing, and associated transport operations to evaluate net energy yields (NEYs) and environmental impacts.

  5. A portrait of a sucker using landscape genetics: how colonization and life history undermine the idealized dendritic metapopulation.

    Science.gov (United States)

    Salisbury, Sarah J; McCracken, Gregory R; Keefe, Donald; Perry, Robert; Ruzzante, Daniel E

    2016-09-01

    Dendritic metapopulations have been attributed unique properties by in silico studies, including an elevated genetic diversity relative to a panmictic population of equal total size. These predictions have not been rigorously tested in nature, nor has there been full consideration of the interacting effects among contemporary landscape features, colonization history and life history traits of the target species. We tested for the effects of dendritic structure as well as the relative importance of life history, environmental barriers and historical colonization on the neutral genetic structure of a longnose sucker (Catostomus catostomus) metapopulation in the Kogaluk watershed of northern Labrador, Canada. Samples were collected from eight lakes, genotyped with 17 microsatellites, and aged using opercula. Lakes varied in differentiation, historical and contemporary connectivity, and life history traits. Isolation by distance was detected only by removing two highly genetically differentiated lakes, suggesting a lack of migration-drift equilibrium and the lingering influence of historical factors on genetic structure. Bayesian analyses supported colonization via the Kogaluk's headwaters. The historical concentration of genetic diversity in headwaters inferred by this result was supported by high historical and contemporary effective sizes of the headwater lake, T-Bone. Alternatively, reduced allelic richness in headwaters confirmed the dendritic structure's influence on gene flow, but this did not translate to an elevated metapopulation effective size. A lack of equilibrium and upstream migration may have dampened the effects of dendritic structure. We suggest that interacting historical and contemporary factors prevent the achievement of the idealized traits of a dendritic metapopulation in nature.

  6. The emergence of the rescue effect from explicit within and between-patch dynamics in a metapopulation

    KAUST Repository

    Eriksson, Anders

    2014-02-12

    Immigration can rescue local populations from extinction, helping to stabilize a metapopulation. Local population dynamics is important for determining the strength of this rescue effect, but the mechanistic link between local demographic parameters and the rescue effect at the metapopulation level has received very little attention by modellers. We develop an analytical framework that allows us to describe the emergence of the rescue effect from interacting local stochastic dynamics. We show this framework to be applicable to a wide range of spatial scales, providing a powerful and convenient alternative to individual-based models for making predictions concerning the fate of metapopulations. We show that the rescue effect plays an important role in minimizing the increase in local extinction probability associated with high demographic stochasticity, but its role is more limited in the case of high local environmental stochasticity of recruitment or survival. While most models postulate the rescue effect, our framework provides an explicit mechanistic link between local dynamics and the emergence of the rescue effect, and more generally the stability of the whole metapopulation. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  7. Geographical patterns of dominant bivalves and a polychaete in Europe: no metapopulations in the marine coastal zone?

    NARCIS (Netherlands)

    Hummel, H.

    2003-01-01

    The genetic diversity, differentiation and performance of some dominant invertebrates in the marine coastal zone of Europe are reviewed in order to discuss the use of the metapopulation concept in the marine coastal realm. A consistently high genetic diversity of the species studied (mussels of the

  8. OPTIMISASI SISTEM USAHA TANI UNTUK PERTANIAN BERKELANJUTAN DI KAWASAN PESISIR BALI UTARA (Optimization of Farming System Towards Sustainable Agriculture in North Coastal Plain Bali

    Directory of Open Access Journals (Sweden)

    I Wayan Budiasa

    2007-11-01

    system development (FSD on poor fertile soil with limited water source can lead to trade-off between economic benefit in the short run and environmental problems in the long run. As environmental degradation increases and inefficient in resources allocation, farming system will become unsustainable. This study aims to optimize irrigated farming system model and to assess its sustainability. By using linear programming analysis, local farmer in north coastal plain of Bali was optimal in resources allocation indicated from optimal solution of conventional farming system model which conforms to observed behavior. By several adjustments, conventional farming system model can be extended to sustainable farming system model. It is found that the sustainable farming system is better than the conventional farming system. Since all components and indicators of sustainability were considered into model and all criteria of sustainability were fulfilled by optimal results, the extended farming system model also guarantees that irrigated farming system development at household level will become sustaipable. To make the sustainable farming system at household level, the farmer should be able to allocate the groundwater less than or equal to 8.547 Lis, to add the organic fertilizer from manure more than or equal to 5 t/ha/yr, to continue the mixed-farming system and crops rotation, to consider minimum household expenditure, and to put the sustainable value in the use of water in approximately Rp I ,218.29/CM into effect. The sustainable farming system model generated from this study passed validated process. Thus, it can be contributed to scientific development. Also, its results can become best management practices by local farmers on their farms.

  9. Matrix matters: differences of grand skink metapopulation parameters in native tussock grasslands and exotic pasture grasslands.

    Directory of Open Access Journals (Sweden)

    Konstanze Gebauer

    Full Text Available Modelling metapopulation dynamics is a potentially very powerful tool for conservation biologists. In recent years, scientists have broadened the range of variables incorporated into metapopulation modelling from using almost exclusively habitat patch size and isolation, to the inclusion of attributes of the matrix and habitat patch quality. We investigated the influence of habitat patch and matrix characteristics on the metapopulation parameters of a highly endangered lizard species, the New Zealand endemic grand skink (Oligosoma grande taking into account incomplete detectability. The predictive ability of the developed zxmetapopulation model was assessed through cross-validation of the data and with an independent data-set. Grand skinks occur on scattered rock-outcrops surrounded by indigenous tussock (bunch and pasture grasslands therefore implying a metapopulation structure. We found that the type of matrix surrounding the habitat patch was equally as important as the size of habitat patch for estimating occupancy, colonisation and extinction probabilities. Additionally, the type of matrix was more important than the physical distance between habitat patches for colonisation probabilities. Detection probability differed between habitat patches in the two matrix types and between habitat patches with different attributes such as habitat patch composition and abundance of vegetation on the outcrop. The developed metapopulation models can now be used for management decisions on area protection, monitoring, and the selection of translocation sites for the grand skink. Our study showed that it is important to incorporate not only habitat patch size and distance between habitat patches, but also those matrix type and habitat patch attributes which are vital in the ecology of the target species.

  10. Matrix matters: differences of grand skink metapopulation parameters in native tussock grasslands and exotic pasture grasslands.

    Science.gov (United States)

    Gebauer, Konstanze; Dickinson, Katharine J M; Whigham, Peter A; Seddon, Philip J

    2013-01-01

    Modelling metapopulation dynamics is a potentially very powerful tool for conservation biologists. In recent years, scientists have broadened the range of variables incorporated into metapopulation modelling from using almost exclusively habitat patch size and isolation, to the inclusion of attributes of the matrix and habitat patch quality. We investigated the influence of habitat patch and matrix characteristics on the metapopulation parameters of a highly endangered lizard species, the New Zealand endemic grand skink (Oligosoma grande) taking into account incomplete detectability. The predictive ability of the developed zxmetapopulation model was assessed through cross-validation of the data and with an independent data-set. Grand skinks occur on scattered rock-outcrops surrounded by indigenous tussock (bunch) and pasture grasslands therefore implying a metapopulation structure. We found that the type of matrix surrounding the habitat patch was equally as important as the size of habitat patch for estimating occupancy, colonisation and extinction probabilities. Additionally, the type of matrix was more important than the physical distance between habitat patches for colonisation probabilities. Detection probability differed between habitat patches in the two matrix types and between habitat patches with different attributes such as habitat patch composition and abundance of vegetation on the outcrop. The developed metapopulation models can now be used for management decisions on area protection, monitoring, and the selection of translocation sites for the grand skink. Our study showed that it is important to incorporate not only habitat patch size and distance between habitat patches, but also those matrix type and habitat patch attributes which are vital in the ecology of the target species.

  11. Exact solution for a metapopulation version of Schelling’s model

    Science.gov (United States)

    Durrett, Richard; Zhang, Yuan

    2014-01-01

    In 1971, Schelling introduced a model in which families move if they have too many neighbors of the opposite type. In this paper, we will consider a metapopulation version of the model in which a city is divided into N neighborhoods, each of which has L houses. There are ρNL red families and ρNL blue families for some ρ ρb, a new segregated equilibrium appears; for ρb < ρ < ρd, there is bistability, but when ρ increases past ρd the random state is no longer stable. When ρc is small enough, the random state will again be the stationary distribution when ρ is close to 1/2. If so, this is preceded by a region of bistability. PMID:25225367

  12. Local enrichment and its nonlocal consequences for victim-exploiter metapopulations

    CERN Document Server

    Yaari, Gur; Schiffer, Marcelo; Shnerb, Nadav M

    2008-01-01

    The stabilizing effects of local enrichment are revisited. Diffusively coupled host-parasitoid and predator-prey metapopulations are shown to admit a stable fixed point, limit cycle or stable torus with a rich bifurcation structure. A linear toy model that yields many of the basic qualitative features of this system is presented. The further nonlinear complications are analyzed in the framework of the marginally stable Lotka-Volterra model, and the continuous time analog of the unstable, host-parasitoid Nicholson-Bailey model. The dependence of the results on the migration rate and level of spatial variations is examined, and the possibility of "nonlocal" effect of enrichment, where local enrichment induces stable oscillations at a distance, is studied. A simple method for basic estimation of the relative importance of this effect in experimental systems is presented and exemplified.

  13. Node discovery in meta-population network behind infectious disease outbreak

    CERN Document Server

    Maeno, Yoshiharu

    2010-01-01

    Stochasticity and spatial heterogeneity are of great interest recently in studying the spread of an infectious disease. Populations in a combination of epidemiological compartment models and a meta-population network model are described by stochastic differential equations. The presented method solves a node discovery problem to identify the nodes within a given dataset which are directly influenced by an unknown neighboring node during the spread. The dataset is either the time sequence data on the number of infectious persons or new cases in the early growth phase of an infectious disease outbreak. The network topology and transmission parameters are revealed by the maximal likelihood estimation. The degree of influence on individual nodes from an unknown origin is calculated with the technique of the extreme sequence detection given the revealed topology and parameters. The method is tested with computationally synthesized datasets and the WHO dataset on SARS outbreak.

  14. Mobility-enhanced signal response in metapopulation networks of coupled oscillators

    CERN Document Server

    Shen, Chuansheng; Hou, Zhonghuai

    2013-01-01

    We investigate the effect of mobility on the response of coupled oscillators to a subthreshold external signal in metapopulation networks, wherein each node represents a subpopulation with overdamped bistable oscillators that can randomly diffuse between nodes. With increasing mobility rate, the oscillators undergo transitions from intrawell to interwell motion, demonstrating clearly mobility-enhanced signal amplification. Moreover, the response shows nonmonotonic dependence on the mobility rate, i.e., a maximal gain occurs at a moderate level of mobility. This interesting phenomenon is robust against variations in the overall density, network size, as well as network topology. In addition, a simple mean-field analysis is carried out to qualitatively illustrate the simulation results.

  15. Optimal Siting of Charging Stations for Electric Vehicles Based on Fuzzy Delphi and Hybrid Multi-Criteria Decision Making Approaches from an Extended Sustainability Perspective

    Directory of Open Access Journals (Sweden)

    Huiru Zhao

    2016-04-01

    Full Text Available Optimal siting of electric vehicle charging stations (EVCSs is crucial to the sustainable development of electric vehicle systems. Considering the defects of previous heuristic optimization models in tackling subjective factors, this paper employs a multi-criteria decision-making (MCDM framework to address the issue of EVCS siting. The initial criteria for optimal EVCS siting are selected from extended sustainability theory, and the vital sub-criteria are further determined by using a fuzzy Delphi method (FDM, which consists of four pillars: economy, society, environment and technology perspectives. To tolerate vagueness and ambiguity of subjective factors and human judgment, a fuzzy Grey relation analysis (GRA-VIKOR method is employed to determine the optimal EVCS site, which also improves the conventional aggregating function of fuzzy Vlsekriterijumska Optimizacijia I Kompromisno Resenje (VIKOR. Moreover, to integrate the subjective opinions as well as objective information, experts’ ratings and Shannon entropy method are employed to determine combination weights. Then, the applicability of proposed framework is demonstrated by an empirical study of five EVCS site alternatives in Tianjin. The results show that A3 is selected as the optimal site for EVCS, and sub-criteria affiliated with environment obtain much more attentions than that of other sub-criteria. Moreover, sensitivity analysis indicates the selection results remains stable no matter how sub-criteria weights are changed, which verifies the robustness and effectiveness of proposed model and evaluation results. This study provides a comprehensive and effective method for optimal siting of EVCS and also innovates the weights determination and distance calculation for conventional fuzzy VIKOR.

  16. Multi-Objective Sustainable Operation of the Three Gorges Cascaded Hydropower System Using Multi-Swarm Comprehensive Learning Particle Swarm Optimization

    Directory of Open Access Journals (Sweden)

    Xiang Yu

    2016-06-01

    Full Text Available Optimal operation of hydropower reservoir systems often needs to optimize multiple conflicting objectives simultaneously. The conflicting objectives result in a Pareto front, which is a set of non-dominated solutions. Non-dominated solutions cannot outperform each other on all the objectives. An optimization framework based on the multi-swarm comprehensive learning particle swarm optimization algorithm is proposed to solve the multi-objective operation of hydropower reservoir systems. Through adopting search techniques such as decomposition, mutation and differential evolution, the algorithm tries to derive multiple non-dominated solutions reasonably distributed over the true Pareto front in one single run, thereby facilitating determining the final tradeoff. The long-term sustainable planning of the Three Gorges cascaded hydropower system consisting of the Three Gorges Dam and Gezhouba Dam located on the Yangtze River in China is studied. Two conflicting objectives, i.e., maximizing hydropower generation and minimizing deviation from the outflow lower target to realize the system’s economic, environmental and social benefits during the drought season, are optimized simultaneously. Experimental results demonstrate that the optimization framework helps to robustly derive multiple feasible non-dominated solutions with satisfactory convergence, diversity and extremity in one single run for the case studied.

  17. Initial genetic diversity enhances population establishment and alters genetic structuring of a newly established Daphnia metapopulation.

    Science.gov (United States)

    Holmes, Christopher J; Pantel, Jelena H; Schulz, Kimberly L; Cáceres, Carla E

    2016-07-01

    When newly created habitats are initially colonized by genotypes with rapid population growth rates, later arriving colonists may be prevented from establishing. Although these priority effects have been documented in multiple systems, their duration may be influenced by the diversity of the founding population. We conducted a large-scale field manipulation to investigate how initial clonal diversity influences temporal and landscape patterns of genetic structure in a developing metapopulation. Six genotypes of obligately asexual Daphnia pulex were stocked alone (no clonal diversity) or in combination ('high' clonal diversity) into newly created experimental woodland ponds. We also measured the population growth rate of all clones in the laboratory when raised on higher-quality and lower-quality resources. Our predictions were that in the 3 years following stocking, clonally diverse populations would be more likely to persist than nonclonally diverse populations and exhibit evidence for persistent founder effects. We expected that faster growing clones would be found in more pools and comprise a greater proportion of individuals genotyped from the landscape. Genetic composition, both locally and regionally, changed significantly following stocking. Six of 27 populations exhibited evidence for persistent founder effects, and populations stocked with 'high' clonal diversity were more likely to exhibit these effects than nonclonally diverse populations. Performance in the laboratory was not predictive of clonal persistence or overall dominance in the field. Hence, we conclude that although laboratory estimates of fitness did not fully explain metapopulation genetic structure, initial clonal diversity did enhance D. pulex population establishment and persistence in this system.

  18. Find the weakest link. A comparison between demographic, genetic and demo-genetic metapopulation extinction times

    Directory of Open Access Journals (Sweden)

    Robert Alexandre

    2011-09-01

    Full Text Available Abstract Background While the ultimate causes of most species extinctions are environmental, environmental constraints have various secondary consequences on evolutionary and ecological processes. The roles of demographic, genetic mechanisms and their interactions in limiting the viabilities of species or populations have stirred much debate and remain difficult to evaluate in the absence of demography-genetics conceptual and technical framework. Here, I computed projected times to metapopulation extinction using (1 a model focusing on the effects of species properties, habitat quality, quantity and temporal variability on the time to demographic extinction; (2 a genetic model focusing on the dynamics of the drift and inbreeding loads under the same species and habitat constraints; (3 a demo-genetic model accounting for demographic-genetic processes and feedbacks. Results Results indicate that a given population may have a high demographic, but low genetic viability or vice versa; and whether genetic or demographic aspects will be the most limiting to overall viability depends on the constraints faced by the species (e.g., reduction of habitat quantity or quality. As a consequence, depending on metapopulation or species characteristics, incorporating genetic considerations to demographically-based viability assessments may either moderately or severely reduce the persistence time. On the other hand, purely genetically-based estimates of species viability may either underestimate (by neglecting demo-genetic interactions or overestimate (by neglecting the demographic resilience true viability. Conclusion Unbiased assessments of the viabilities of species may only be obtained by identifying and considering the most limiting processes (i.e., demography or genetics, or, preferentially, by integrating them.

  19. Local competition and metapopulation processes drive long-term seagrass-epiphyte population dynamics.

    Science.gov (United States)

    Lobelle, Delphine; Kenyon, Emma J; Cook, Kevan J; Bull, James C

    2013-01-01

    It is well known that ecological processes such as population regulation and natural enemy interactions potentially occur over a range of spatial scales, and there is a substantial body of literature developing theoretical understanding of the interplay between these processes. However, there are comparatively few studies quantifying the long-term effects of spatial scaling in natural ecosystems. A key challenge is that trophic complexity in real-world biological communities quickly obscures the signal from a focal process. Seagrass meadows provide an excellent opportunity in this respect: in many instances, seagrasses effectively form extensive natural monocultures, in which hypotheses about endogenous dynamics can be formulated and tested. We present amongst the longest unbroken, spatially explict time series of seagrass abundance published to date. Data include annual measures of shoot density, total above-ground abundance, and associated epiphyte cover from five Zostera marina meadows distributed around the Isles of Scilly, UK, from 1996 to 2011. We explore empirical patterns at the local and metapopulation scale using standard time series analysis and develop a simple population dynamic model, testing the hypothesis that both local and metapopulation scale feedback processes are important. We find little evidence of an interaction between scales in seagrass dynamics but that both scales contribute approximately equally to observed local epiphyte abundance. By quantifying the long-term dynamics of seagrass-epiphyte interactions we show how measures of density and extent are both important in establishing baseline information relevant to predicting responses to environmental change and developing management plans. We hope that this study complements existing mechanistic studies of physiology, genetics and productivity in seagrass, whilst highlighting the potential of seagrass as a model ecosystem. More generally, this study provides a rare opportunity to test

  20. Optimism

    Science.gov (United States)

    Carver, Charles S.; Scheier, Michael F.; Segerstrom, Suzanne C.

    2010-01-01

    Optimism is an individual difference variable that reflects the extent to which people hold generalized favorable expectancies for their future. Higher levels of optimism have been related prospectively to better subjective well-being in times of adversity or difficulty (i.e., controlling for previous well-being). Consistent with such findings, optimism has been linked to higher levels of engagement coping and lower levels of avoidance, or disengagement, coping. There is evidence that optimism is associated with taking proactive steps to protect one's health, whereas pessimism is associated with health-damaging behaviors. Consistent with such findings, optimism is also related to indicators of better physical health. The energetic, task-focused approach that optimists take to goals also relates to benefits in the socioeconomic world. Some evidence suggests that optimism relates to more persistence in educational efforts and to higher later income. Optimists also appear to fare better than pessimists in relationships. Although there are instances in which optimism fails to convey an advantage, and instances in which it may convey a disadvantage, those instances are relatively rare. In sum, the behavioral patterns of optimists appear to provide models of living for others to learn from. PMID:20170998

  1. Sustainability - and sustainable transport

    Energy Technology Data Exchange (ETDEWEB)

    Thisgaard, P.

    1996-12-31

    To gain the fulfillment of basic sustainable objectives in a medium- and long-term perspective for transport. The necessary activities must be genuinely complementary i.e. it must solve problems within at least two sectors and at the same time this activity must be sustainable in a Brundtland report perspective. The transport sector must take steps to develop an `ECO-NOMY`. The principle here is a `fusion` of economy and ecology, and the first place this can take place is in the transport sector. This can only take place in a close cooperation between the transport sector and the other sectors of society. Methods to carry out cross-sectional priorities and allocation of resources must be developed in order to avoid societal sub-optimization of single issue solutions. Besides, a development of public administration must take place through a very heavy limitation of the principles of `sector thinking` as well as the carrying through of totally new principles in the selection of personnel as well as the principles of promotion and control. `Management by objectives` combined with an emphasis of certain moral codes - may contribute substantially to such a development. The principles are to economize with resources and as far as possible adjust the supply to a given demand with reasonable regard to comfort and transport considerations. Besides, the transport sector must try to solve other sector`s sociological problems and actively try to point out where other sectors create problems for the transport sector which prevent this in becoming `sustainable`. The transport sector must also continually try to forward its ability to change by avoiding capital investment or other forms of bindings which might hinder a different development if or when important technological changes occur. In a number of ways you can point to different concrete possibilities with the following headlines: diversification, integration, development of vehicles, information and concrete project areas

  2. Optimization

    CERN Document Server

    Pearce, Charles

    2009-01-01

    Focuses on mathematical structure, and on real-world applications. This book includes developments in several optimization-related topics such as decision theory, linear programming, turnpike theory, duality theory, convex analysis, and queuing theory.

  3. A Spatial Optimization Model for Sustainable Land Use at Regional Level in China: A Case Study for Poyang Lake Region

    NARCIS (Netherlands)

    Chen Wenbo,; Carsjens, G.J.; Zhao, L.; Li, H.

    2015-01-01

    Economic growth in China is accompanied by many problems, such as rapid deterioration of the environment and a sharp decline in the area of arable land. China’s current land-use planning system fails to deal with these problems, especially at the regional level. The lack of sustainable spatial alloc

  4. Optimal and Sustainable Plant Refurbishment in Historical Buildings: A Study of an Ancient Monastery Converted into a Showroom in Florence

    Directory of Open Access Journals (Sweden)

    Carla Balocco

    2013-04-01

    Full Text Available The aim of this research is to study the possibility and sustainability of retrofit and refurbishment design solutions on historical buildings converted to different uses and often clashing with their original purpose and architectural features. The building studied is an ancient monastery located in the historical center of Florence (Italy. Today the original cloister is covered over by a single glazed pitched roof and used as a fashion showroom. Our proposed solution concerns a reversible and sustainable plant design integrated with an active transparent building casing. The existing glazed pitched roof was reconsidered and re-designed as part of the existing heating, ventilation and air conditioning (HVAC plant system, based on the functioning of an active thermal buffer to control the high heat flow rates and external thermal loads due to solar radiation. Hourly whole building energy analysis was carried out to check the effectiveness and energy sustainability of our proposed solution. Results obtained showed, from the historical-architectural, energy and environmental points of view, its sustainability due to the building-plant system integration and interaction with its location, the external climatic conditions and defined expected uses, in particular with reference to indoor thermal comfort.

  5. The different sources of variation in inbreeding depression, heterosis and outbreeding depression in a metapopulation of Physa acuta.

    Science.gov (United States)

    Escobar, Juan Sebastián; Nicot, Antoine; David, Patrice

    2008-11-01

    Understanding how parental distance affects offspring fitness, i.e., the effects of inbreeding and outbreeding in natural populations, is a major goal in evolutionary biology. While inbreeding is often associated with fitness reduction (inbreeding depression), interpopulation outcrossing may have either positive (heterosis) or negative (outbreeding depression) effects. Within a metapopulation, all phenomena may occur with various intensities depending on the focal population (especially its effective size) and the trait studied. However, little is known about interpopulation variation at this scale. We here examine variation in inbreeding depression, heterosis, and outbreeding depression on life-history traits across a full-life cycle, within a metapopulation of the hermaphroditic snail Physa acuta. We show that all three phenomena can co-occur at this scale, although they are not always expressed on the same traits. A large variation in inbreeding depression, heterosis, and outbreeding depression is observed among local populations. We provide evidence that, as expected from theory, small and isolated populations enjoy higher heterosis upon outcrossing than do large, open populations. These results emphasize the need for an integrated theory accounting for the effects of both deleterious mutations and genetic incompatibilities within metapopulations and to take into account the variability of the focal population to understand the genetic consequences of inbreeding and outbreeding at this scale.

  6. Optimal Decision Model for Sustainable Hospital Building Renovation—A Case Study of a Vacant School Building Converting into a Community Public Hospital

    Science.gov (United States)

    Juan, Yi-Kai; Cheng, Yu-Ching; Perng, Yeng-Horng; Castro-Lacouture, Daniel

    2016-01-01

    Much attention has been paid to hospitals environments since modern pandemics have emerged. The building sector is considered to be the largest world energy consumer, so many global organizations are attempting to create a sustainable environment in building construction by reducing energy consumption. Therefore, maintaining high standards of hygiene while reducing energy consumption has become a major task for hospitals. This study develops a decision model based on genetic algorithms and A* graph search algorithms to evaluate existing hospital environmental conditions and to recommend an optimal scheme of sustainable renovation strategies, considering trade-offs among minimal renovation cost, maximum quality improvement, and low environmental impact. Reusing vacant buildings is a global and sustainable trend. In Taiwan, for example, more and more school space will be unoccupied due to a rapidly declining birth rate. Integrating medical care with local community elder-care efforts becomes important because of the aging population. This research introduces a model that converts a simulated vacant school building into a community public hospital renovation project in order to validate the solutions made by hospital managers and suggested by the system. The result reveals that the system performs well and its solutions are more successful than the actions undertaken by decision-makers. This system can improve traditional hospital building condition assessment while making it more effective and efficient. PMID:27347986

  7. Optimal Decision Model for Sustainable Hospital Building Renovation-A Case Study of a Vacant School Building Converting into a Community Public Hospital.

    Science.gov (United States)

    Juan, Yi-Kai; Cheng, Yu-Ching; Perng, Yeng-Horng; Castro-Lacouture, Daniel

    2016-06-24

    Much attention has been paid to hospitals environments since modern pandemics have emerged. The building sector is considered to be the largest world energy consumer, so many global organizations are attempting to create a sustainable environment in building construction by reducing energy consumption. Therefore, maintaining high standards of hygiene while reducing energy consumption has become a major task for hospitals. This study develops a decision model based on genetic algorithms and A* graph search algorithms to evaluate existing hospital environmental conditions and to recommend an optimal scheme of sustainable renovation strategies, considering trade-offs among minimal renovation cost, maximum quality improvement, and low environmental impact. Reusing vacant buildings is a global and sustainable trend. In Taiwan, for example, more and more school space will be unoccupied due to a rapidly declining birth rate. Integrating medical care with local community elder-care efforts becomes important because of the aging population. This research introduces a model that converts a simulated vacant school building into a community public hospital renovation project in order to validate the solutions made by hospital managers and suggested by the system. The result reveals that the system performs well and its solutions are more successful than the actions undertaken by decision-makers. This system can improve traditional hospital building condition assessment while making it more effective and efficient.

  8. Optimal allocation of fault current limiters for sustaining overcurrent relays coordination in a power system with distributed generation

    Directory of Open Access Journals (Sweden)

    A. Elmitwally

    2015-12-01

    Full Text Available This paper addresses the problem of overcurrent relays (OCRs coordination in the presence of DGs. OCRs are optimally set to work in a coordinated manner to isolate faults with minimal impacts on customers. The penetration of DGs into the power system changes the fault current levels seen by the OCRs. This can deteriorate the coordinated operation of OCRs. Operation time difference between backup and main relays can be below the standard limit or even the backup OCR can incorrectly work before the main OCR. Though resetting of OCRs is tedious especially in large systems, it cannot alone restore the original coordinated operation in the presence of DGs. The paper investigates the optimal utilization of fault current limiters (FCLs to maintain the directional OCRs coordinated operation without any need to OCRs resetting irrespective of DGs status. It is required to maintain the OCRs coordination at minimum cost of prospective FCLs. Hence, the FCLs location and sizing problem is formulated as a constrained multi-objective optimization problem. Multi-objective particle swarm optimization is adopted for solving the optimization problem to determine the optimal locations and sizes of FCLs. The proposed algorithm is applied to meshed and radial power systems at different DGs arrangements using different types of FCLs. Moreover, the OCRs coordination problem is studied when the system includes both directional and non-directional OCRs. Comparative analysis of results is provided.

  9. Quantifying the importance of patch-specific changes in habitat to metapopulation viability of an endangered songbird.

    Science.gov (United States)

    Horne, Jon S; Strickler, Katherine M; Alldredge, Mathew

    2011-10-01

    A growing number of programs seek to facilitate species conservation using incentive-based mechanisms. Recently, a market-based incentive program for the federally endangered Golden-cheeked Warbler (Dendroica chrysoparia) was implemented on a trial basis at Fort Hood, an Army training post in Texas, USA. Under this program, recovery credits accumulated by Fort Hood through contracts with private landowners are used to offset unintentional loss of breeding habitat of Golden-cheeked Warblers within the installation. Critical to successful implementation of such programs is the ability to value, in terms of changes to overall species viability, both habitat loss and habitat restoration or protection. In this study, we sought to answer two fundamental questions: Given the same amount of change in breeding habitat, does the change in some patches have a greater effect on metapopulation persistence than others? And if so, can characteristics of a patch (e.g., size or spatial location) be used to predict how the metapopulation will respond to these changes? To answer these questions, we describe an approach for using sensitivity analysis of a metapopulation projection model to predict how changes to specific habitat patches would affect species viability. We used a stochastic, discrete-time projection model based on stage-specific estimates of survival and fecundity, as well as various assumptions about dispersal among populations. To assess a particular patch's leverage, we quantified how much metapopulation viability was expected to change in response to changing the size of that patch. We then related original patch size and distance from the largest patch to each patch's leverage to determine if general patch characteristics could be used to develop guidelines for valuing changes to patches within a metapopulation. We found that both the characteristic that best predicted patch leverage and the magnitude of the relationship changed under different model scenarios

  10. Advising and Optimizing the Deployment of Sustainability-Oriented Technologies in the Integrated Electricity, Light-Duty Transportation, and Water Supply System

    Science.gov (United States)

    Tarroja, Brian

    The convergence of increasing populations, decreasing primary resource availability, and uncertain climates have drawn attention to the challenge of shifting the operations of key resource sectors towards a sustainable paradigm. This is prevalent in California, which has set sustainability-oriented policies such as the Renewable Portfolio Standards and Zero-Emission Vehicle mandates. To meet these goals, many options have been identified to potentially carry out these shifts. The electricity sector is focusing on accommodating renewable power generation, the transportation sector on alternative fuel drivetrains and infrastructure, and the water supply sector on conservation, reuse, and unconventional supplies. Historical performance evaluations of these options, however, have not adequately taken into account the impacts on and constraints of co-dependent infrastructures that must accommodate them and their interactions with other simultaneously deployed options. These aspects are critical for optimally choosing options to meet sustainability goals, since the combined system of all resource sectors must satisfy them. Certain operations should not be made sustainable at the expense of rendering others as unsustainable, and certain resource sectors should not meet their individual goals in a way that hinders the ability of the entire system to do so. Therefore, this work develops and utilizes an integrated platform of the electricity, transportation, and water supply sectors to characterize the performance of emerging technology and management options while taking into account their impacts on co-dependent infrastructures and identify synergistic or detrimental interactions between the deployment of different options. This is carried out by first evaluating the performance of each option in the context of individual resource sectors to determine infrastructure impacts, then again in the context of paired resource sectors (electricity-transportation, electricity

  11. Sustainability and optimal control of an exploited prey predator system through provision of alternative food to predator.

    Science.gov (United States)

    Kar, T K; Ghosh, Bapan

    2012-08-01

    In the present paper, we develop a simple two species prey-predator model in which the predator is partially coupled with alternative prey. The aim is to study the consequences of providing additional food to the predator as well as the effects of harvesting efforts applied to both the species. It is observed that the provision of alternative food to predator is not always beneficial to the system. A complete picture of the long run dynamics of the system is discussed based on the effort pair as control parameters. Optimal augmentations of prey and predator biomass at final time have been investigated by optimal control theory. Also the short and large time effects of the application of optimal control have been discussed. Finally, some numerical illustrations are given to verify our analytical results with the help of different sets of parameters.

  12. Patterns and persistence of larval retention and connectivity in a marine fish metapopulation

    KAUST Repository

    Saenz Agudelo, Pablo

    2012-08-14

    Connectivity, the demographic linking of local populations through the dispersal of individuals, is one of the most poorly understood processes in population dynamics, yet has profound implications for conservation and harvest strategies. For marine species with pelagic larvae, direct estimation of connectivity remains logistically challenging and has mostly been limited to single snapshots in time. Here, we document seasonal and interannual patterns of larval dispersal in a metapopulation of the coral reef fish Amphiprion polymnus. A 3-year record of larval trajectories within and among nine discrete local populations from an area of approximately 35 km was established by determining the natal origin of settled juveniles through DNA parentage analysis. We found that spatial patterns of both self-recruitment and connectivity were remarkably consistent over time, with a low level of self-recruitment at the scale of individual sites. Connectivity among sites was common and multidirectional in all years and was not significantly influenced by seasonal variability of predominant surface current directions. However, approximately 75% of the sampled juveniles could not be assigned to parents within the study area, indicating high levels of immigrations from sources outside the study area. The data support predictions that the magnitude and temporal stability of larval connectivity decreases significantly with increasing distance between subpopulations, but increases with the size of subpopulations. Given the considerable effort needed to directly measure larval exchange, the consistent patterns suggest snapshot parentage analyses can provide useful dispersal estimates to inform spatial management decisions. © 2012 Blackwell Publishing Ltd.

  13. On biodiversity in river networks: A trade-off metapopulation model and comparative analysis

    Science.gov (United States)

    Muneepeerakul, R.; Levin, S. A.; Rinaldo, A.; Rodriguez-Iturbe, I.

    2007-07-01

    A discrete, structured metapopulation model is coupled with the strictly hierarchical competition-colonization trade-off model, in which competitively superior species have lower fecundity rates and thus lower colonizing ability, to study the resulting biodiversity patterns in river networks. These patterns are then compared with those resulting from the neutral dynamics, in which every species has the same fecundity rate and is competitively equivalent at a per capita level. Significant differences exist between riparian biodiversity patterns and those predicted by theories developed for two-dimensional landscapes. We find that dispersal directionality and network structure promote species that produce a large number of propagules at a species level; such species are considered competitively superior in the neutral model and inferior in the trade-off model. As a result, the two key characteristics of riparian systems, dispersal directionality and network structure, lead to lower and higher overall γ diversity in the former and the latter models, respectively. The network structure, through the containment effect due to limited cross-basin dispersal, always leads to higher between-community, β diversity. The spatial distribution of local, α diversity becomes heterogeneous and thus important under directional dispersal and network structure. A higher degree of dividedness results in higher γ diversity for communities obeying both neutral and trade-off models, but the increase is more dramatic in the latter.

  14. Metapopulation structure in the lagoon cockle Cerastoderma lamarcki in the northern Wadden Sea

    Science.gov (United States)

    Reise, Karsten

    2003-01-01

    Benthic invertebrates in discontinuous inshore habitats and with short or no pelagic larval dispersal are likely to exhibit regional metapopulation dynamics with partially isolated local populations. Near the island of Sylt, the bivalve Cerastoderma (Cardium) lamarcki (Reeve, 1844, syn. in part with C. glaucum Bruguiére, 1789) was widespread in intertidal seagrass beds, coexisting with the sibling species C. edule (Linné, 1758). However, the last C. lamarcki in this habitat was found in 1980. At present the lagoon cockle is restricted to disjunct ditches, creeks and ponds within island salt marshes. There it differs in year-class structure between localities. Successful recruitment events did not coincide. At one locality, a period with regular recruitment was followed by 5 years of recruitment failure, resulting in an overaged population probably at the rim of extinction. In a nearby brackish pond, extinction was followed by recolonization 3 years later. Other lagoonal habitats which seem to be suitable are without cockles. It is speculated that small and isolated habitats occasionally receive colonizers by eggs and juveniles adhering to avian vectors.

  15. Asymmetric or diffusive co-evolution generates meta-populations in fig-fig wasp mutualisms.

    Science.gov (United States)

    Wang, RuiWu; Yang, Yan; Wiggins, Natasha L

    2014-06-01

    Co-evolutionary theory assumes co-adapted characteristics are a positive response to counter those of another species, whereby co-evolved species reach an evolutionarily stable interaction through bilateral adaptation. However, evidence from the fig-fig wasp mutualistic system implies very different co-evolutionary selection mechanisms, due to the inherent conflict among interacted partners. Fig plants appear to have discriminatively enforced fig wasps to evolve "adaptation characteristics" that provide greater benefit to the fig, and fig wasps appear to have diversified their evolutionary strategies in response to discriminative enforcement by figs and competition among different fig wasp species. In what appears to be an asymmetric interaction, the prosperity of cooperative pollinating wasps should inevitably lead to population increases of parasitic individuals, thus resulting in localized extinctions of pollinating wasps. In response, the sanctioning of parasitic wasps by the fig should lead to a reduction in the parasitic wasp population. The meta-populations created by such asymmetric interactions may result in each population of coevolved species chaotically oscillated, temporally or evolutionarily.

  16. Sulfolobus islandicus meta-populations in Yellowstone National Park hot springs.

    Science.gov (United States)

    Campbell, Kate M; Kouris, Angela; England, Whitney; Anderson, Rika E; McCleskey, R Blaine; Nordstrom, D Kirk; Whitaker, Rachel J

    2017-03-09

    Abiotic and biotic forces shape the structure and evolution of microbial populations. We investigated forces that shape the spatial and temporal population structure of Sulfolobus islandicus by comparing geochemical and molecular analysis from seven hot springs in five regions sampled over three years in Yellowstone National Park. Through deep amplicon sequencing, we uncovered 148 unique alleles at two loci whose relative frequency provides clear evidence for independent populations in different hot springs. Although geography controls regional geochemical composition and population differentiation, temporal changes in population were not explained by corresponding variation in geochemistry. The data suggest that the influence of extinction, bottleneck events, and/or selective sweeps within a spring and low migration between springs shape these populations. We suggest that hydrologic events such as storm events and surface snowmelt runoff destabilize smaller hot spring environments with smaller populations and result in high variation in the S. islandicus population over time. Therefore, physical abiotic features such as hot spring size and position in the landscape are important factors shaping the stability and diversity of the S. islandicus meta-population within Yellowstone National Park. This article is protected by copyright. All rights reserved.

  17. Developing metapopulation connectivity criteria from genetic and habitat data to recover the endangered Mexican wolf.

    Science.gov (United States)

    Carroll, Carlos; Fredrickson, Richard J; Lacy, Robert C

    2014-02-01

    Restoring connectivity between fragmented populations is an important tool for alleviating genetic threats to endangered species. Yet recovery plans typically lack quantitative criteria for ensuring such population connectivity. We demonstrate how models that integrate habitat, genetic, and demographic data can be used to develop connectivity criteria for the endangered Mexican wolf (Canis lupus baileyi), which is currently being restored to the wild from a captive population descended from 7 founders. We used population viability analysis that incorporated pedigree data to evaluate the relation between connectivity and persistence for a restored Mexican wolf metapopulation of 3 populations of equal size. Decreasing dispersal rates greatly increased extinction risk for small populations (0.5 genetically effective migrants per generation may be achievable via natural dispersal under current landscape conditions. When sufficient data are available, these methods allow planners to move beyond general aspirational connectivity goals or rules of thumb to develop objective and measurable connectivity criteria that more effectively support species recovery. The shift from simple connectivity rules of thumb to species-specific analyses parallels the previous shift from general minimum-viable-population thresholds to detailed viability modeling in endangered species recovery planning. © 2013 Society for Conservation Biology.

  18. An integrated knowledge-based and optimization tool for the sustainable selection of wastewater treatment process concepts

    DEFF Research Database (Denmark)

    Castillo, A.; Cheali, Peam; Gómez, V.

    2016-01-01

    The increasing demand on wastewater treatment plants (WWTPs) has involved an interest in improving the alternative treatment selection process. In this study, an integrated framework including an intelligent knowledge-based system and superstructure-based optimization has been developed and appli...

  19. Multi-objective optimization and exergetic-sustainability of an irreversible nano scale Braysson cycle operating with Ma

    Directory of Open Access Journals (Sweden)

    Mohammad H. Ahmadi

    2016-06-01

    Full Text Available Nano technology is developed in this decade and changes the way of life. Moreover, developing nano technology has effect on the performance of the materials and consequently improves the efficiency and robustness of them. So, nano scale thermal cycles will be probably engaged in the near future. In this paper, a nano scale irreversible Braysson cycle is studied thermodynamically for optimizing the performance of the Braysson cycle. In the aforementioned cycle an ideal Maxwell–Boltzmann gas is used as a working fluid. Furthermore, three different plans are used for optimizing with multi-objectives; though, the outputs of the abovementioned plans are assessed autonomously. Throughout the first plan, with the purpose of maximizing the ecological coefficient of performance and energy efficiency of the system, multi-objective optimization algorithms are used. Furthermore, in the second plan, two objective functions containing the ecological coefficient of performance and the dimensionless Maximum available work are maximized synchronously by utilizing multi-objective optimization approach. Finally, throughout the third plan, three objective functions involving the dimensionless Maximum available work, the ecological coefficient of performance and energy efficiency of the system are maximized synchronously by utilizing multi-objective optimization approach. The multi-objective evolutionary approach based on the non-dominated sorting genetic algorithm approach is used in this research. Making a decision is performed by three different decision makers comprising linear programming approaches for multidimensional analysis of preference and an approach for order of preference by comparison with ideal answer and Bellman–Zadeh. Lastly, analysis of error is employed to determine deviation of the outcomes gained from each plan.

  20. A method for economic optimization of energy performance and indoor environment in the design of sustainable buildings

    DEFF Research Database (Denmark)

    Hansen, Sanne; Vanhoutteghem, Lies

    2012-01-01

    Future tightening of the energy requirements increases focus on design of new and better performing buildings with good indoor environment and only limited extra cost compared to new buildings today. This paper presents a method for economic optimization of the design of new low energy dwellings...... in the dynamic simulation tool WinDesign. If any changes have to be made to ensure a good indoor thermal environment, iteration between the two programs must be performed. An example is used to illustrate this process. It indicates that the method can be used from the early design phases to ensure...... that takes into account the indoor thermal environment. By use of the criterion of cost of conserved energy implemented in a Microsoft Excel sheet, a cost optimal design according to a targeted energy frame can be found. The resulting indoor thermal environment is then evaluated based on parametric analysis...

  1. Brackish groundwater membrane system design for sustainable irrigation: Optimal configuration selection using analytic hierarchy process and multi-dimension scaling

    OpenAIRE

    Beni eLew; Lolita eTrachtengertz; Shany eRatsin; Gideon eOron; Amos eBick

    2014-01-01

    The recent high demands for reuse of salty water for irrigation affected membrane producers to assess new potential technologies for undesirable physical, chemical, and biological contaminants removal. This paper studies the assembly options by the analytic hierarchy process (AHP) model and the multi-dimension scaling (MDS) techniques. A specialized form of MDS (CoPlot software) enables presentation of the AHP outcomes in a two dimensional space and the optimal model can be visualized clearly...

  2. Landscape conservation materials. Optimization of the supply of sustainable raw materials by means of implementation of biomass farms; Landschaftpflegematerial. Optimierung einer nachhaltigen Rohstoffbereitstellung durch die Einbindung von Biomassehoefen

    Energy Technology Data Exchange (ETDEWEB)

    Wirkner, Ronny [Deutsches BiomasseForschungsZentrum gGmbH, Leipzig (Germany)

    2011-07-01

    Within the analysis it could be determined the traditional resource wood is a key factor in the context of using renewable energies with a particular focus on biomass. Its multi-functionality leads to an increasing shortage of wood supply, characterized by growing competition in the overlapping fields of material and energy utilization pathways and consequent increased the pressure on a sustainable, ecologically oriented forest management. To increase the wood supply it's necessary to improve the mobilization of sustainable potential of the forest areas, woody biomass from landscape planning, wood waste and alternative options to accelerate the mobilization of wood (fast-growing tree species) and promote long-term adaptation of existing forest management concepts. The optimized provision of woody biomass from landscape planning is more likely to be short-to medium-term options moreover it has the advantage of a targeted use of residual material. But the supply of the material is discontinuous and includes very heterogeneous qualities, which shows the necessity to establish central co-ordination and processing centres to provide a customized marketing. (orig.)

  3. Optimization of Skill Retention in the U. S. Army through Initial Training Analysis and Design: Skill Sustainment Exercises. Volume 3.

    Science.gov (United States)

    1983-05-01

    well. 3. Screws the M605 fuze into fuze well. 4. Buries the mine up to the bottom of the release pin ring. S. Removes the locking safety pin . 6...positive safety pin . MGA SSE-3 TRIAL "- d 7D-Rl31 988 OPTIMIZATION OF SKILL RETENTION IN THE U S RRMY THROUJGH 216 INITIAL TRAINING..(U) MCFANN GRAY...DATE: TASK NO.: 051-192-1012 PAGE I OF I GO NO GO I. Checks mine for boobytraps. 2. Uncovers top of mine. 3. Inserts original safety pin , if available

  4. A metapopulation of the lizard Anguis fragilis (Squamata: Anguidae on a local scale in Dorset, Great Britain, as indicated by spatial distribution and movement

    Directory of Open Access Journals (Sweden)

    Thomas Haley

    2014-12-01

    Full Text Available A metapopulation is a group of spatially structured populations, consisting of distinct units (subpopulations that are separated by space or barriers, and connected by dispersal movements. Evidence derived from Gaussian finite-mixture models and dispersal events suggests that slow-worms may exist in a metapopulation. The Gaussian finite-mixture models showed that slow-worms are aggregated into individual subpopulations; the movement data revealed that males are more likely to migrate than females and that they have the ability to travel sufficiently far to bridge subpopulations. Therefore, the evidence supports the metapopulation theory and that slow-worms exist in multiple small subpopulations instead of one large homogenous population.

  5. Spatio-temporal optimization of agricultural practices to achieve a sustainable development at basin level; framework of a case study in Colombia

    Science.gov (United States)

    Uribe, Natalia; corzo, Gerald; Solomatine, Dimitri

    2016-04-01

    The flood events present during the last years in different basins of the Colombian territory have raised questions on the sensitivity of the regions and if this regions have common features. From previous studies it seems important features in the sensitivity of the flood process were: land cover change, precipitation anomalies and these related to impacts of agriculture management and water management deficiencies, among others. A significant government investment in the outreach activities for adopting and promoting the Colombia National Action Plan on Climate Change (NAPCC) is being carried out in different sectors and regions, having as a priority the agriculture sector. However, more information is still needed in the local environment in order to assess were the regions have this sensitivity. Also the continuous change in one region with seasonal agricultural practices have been pointed out as a critical information for optimal sustainable development. This combined spatio-temporal dynamics of crops cycle in relation to climate change (or variations) has an important impact on flooding events at basin areas. This research will develop on the assessment and optimization of the aggregated impact of flood events due to determinate the spatio-temporal dynamic of changes in agricultural management practices. A number of common best agricultural practices have been identified to explore their effect in a spatial hydrological model that will evaluate overall changes. The optimization process consists on the evaluation of best performance in the agricultural production, without having to change crops activities or move to other regions. To achieve this objectives a deep analysis of different models combined with current and future climate scenarios have been planned. An algorithm have been formulated to cover the parametric updates such that the optimal temporal identification will be evaluated in different region on the case study area. Different hydroinformatics

  6. Brackish groundwater membrane system design for sustainable irrigation: Optimal configuration selection using analytic hierarchy process and multi-dimension scaling

    Directory of Open Access Journals (Sweden)

    Beni eLew

    2014-12-01

    Full Text Available The recent high demands for reuse of salty water for irrigation affected membrane producers to assess new potential technologies for undesirable physical, chemical and biological contaminants removal. This paper studies the assembly options by the analytic hierarchy process (AHP model and the multi-dimension scaling (MDS techniques. A specialized form of MDS (CoPlot software enables presentation of the AHP outcomes in a two dimensional space and the optimal model can be visualized clearly. Four types of 8 membranes were selected: (i Nanofiltration low rejection and high flux (ESNA1-LF-LD, 86% rejection, 10,500gpd; (ii Nanofiltration medium rejection and medium flux (ESNA1-LF2-LD, 91% rejection, 8,200gpd; (iii Reverse Osmosis high rejection and high flux (CPA5-MAX, 99.7 rejection, 12,000gpd ; and (iv Reverse Osmosis medium rejection and extreme high flux (ESPA4-MAX, 99.2 rejection, 13,200gpd. The results indicate that: (i Nanofiltration membrane (High flux and Low rejection can produce water for irrigation with valuable levels of nutrient ions and a reduction in the sodium absorption ratio (SAR, minimizing soil salinity; this is an attractive option for agricultural irrigation and is the optimal solution; and (ii implementing the MDS approach with reference to the variables is consequently useful to characterize membrane system design.

  7. The transition from isolated patches to a metapopulation in the eastern collared lizard in response to prescribed fires.

    Science.gov (United States)

    Templeton, Alan R; Brazeal, Hilary; Neuwald, Jennifer L

    2011-09-01

    Habitat fragmentation often arises from human-induced alterations to the matrix that reduce or eliminate dispersal between habitat patches. Elimination of dispersal increases local extinction and decreases recolonization. These phenomena were observed in the eastern collared lizard (Crotaphytus collaris collaris), which lives in the mid-continental highland region of the Ozarks (Missouri, USA) on glades: habitats of exposed bedrock that form desert-like habitats imbedded in a woodland matrix. With the onset of woodland fire suppression, glade habitats degenerated and the woodland matrix was altered to create a strong barrier to dispersal. By 1980, lizard populations in the Ozarks were rapidly going extinct. In response to this decline, some glades were restored by clearing and burning. Starting in 1984, collared lizard populations were translocated onto these restored habitats. The translocated populations persisted but did not colonize nearby glades or disperse among one another. In 1994 prescribed woodland fires were initiated, which unleashed much dispersal and colonizing behavior. Dispersal was highly nonrandom by both intrinsic variables (age, gender) and extrinsic variables (overall demography, glade population sizes, glade areas, landscape features), resulting in different classes of lizards being dominant in creating demographic cohesiveness among glades, colonizing new glades on a mountain, and colonizing new mountain systems. A dramatic transition was documented from isolated fragments, to a nonequilibrium colonizing metapopulation, and finally to a stable metapopulation. This transition is characterized by the convergence of rates of extinction and recolonization and a major alteration of dispersal probabilities and pattern in going from the nonequilibrium to stable metapopulation states.

  8. Anthropogenic impacts on an oyster metapopulation: Pathogen introduction, climate change and responses to natural selection

    Directory of Open Access Journals (Sweden)

    David Bushek

    2016-08-01

    Full Text Available Abstract Humans rely on marine ecosystems for a variety of services but often impact these ecosystems directly or indirectly limiting their capacity to provide such services. One growing impact is the emergence of marine disease. We present results from a unique case study examining how oysters, a dominant organism in many coastal bays and estuaries that is often harvested for food, have responded to pathogens influenced by human activities, namely the introduction of novel pathogens. Climate change has enabled a northward spread and establishment of Dermo disease in oysters along the eastern seaboard of North America and human activities inadvertently introduced MSX disease along this same coast. Oysters in Delaware Bay have responded differently to each pathogen, and uniquely to MSX disease by developing a highly resistant baywide population not documented in any other bay. Offspring were produced using parents collected from low or high disease (MSX and Dermo regions of Delaware Bay and exposed in a common garden experiment along with a naïve population from Maine. Results indicated widespread resistance to MSX disease, but not to Dermo disease, across Delaware Bay. One striking result was the demonstration of resilience in the population through its capacity to spread, presumably through larval transport, resistance to MSX disease into portions of the population that have experienced little to no MSX disease pressure themselves. Related studies indicated that larval transport mechanisms allowed widespread dispersal such that the entire metapopulation could acquire a high level of resistance over time if disease resistance is sufficiently heritable. The findings have implications for restoration, management and recovery of diseased populations. Namely, that if left to their own devices, natural selection may find a solution that enables populations to recover from introduced pathogens.

  9. Bottlenecks drive temporal and spatial genetic changes in alpine caddisfly metapopulations

    Directory of Open Access Journals (Sweden)

    Jokela Jukka

    2011-09-01

    Full Text Available Abstract Background Extinction and re-colonisation of local populations is common in ephemeral habitats such as temporary streams. In most cases, such population turnover leads to reduced genetic diversity within populations and increased genetic differentiation among populations due to stochastic founder events, genetic drift, and bottlenecks associated with re-colonisation. Here, we examined the spatio-temporal genetic structure of 8 alpine caddisfly populations inhabiting permanent and temporary streams from four valleys in two regions of the Swiss Alps in years before and after a major stream drying event, the European heat wave in summer 2003. Results We found that population turnover after 2003 led to a loss of allelic richness and gene diversity but not to significant changes in observed heterozygosity. Within all valleys, permanent and temporary streams in any given year were not differentiated, suggesting considerable gene flow and admixture between streams with differing hydroperiods. Large changes in allele frequencies after 2003 resulted in a substantial increase in genetic differentiation among valleys within one to two years (1-2 generations driven primarily by drift and immigration. Signatures of genetic bottlenecks were detected in all 8 populations after 2003 using the M-ratio method, but in no populations when using a heterozygosity excess method, indicating differential sensitivity of bottleneck detection methods. Conclusions We conclude that genetic differentiation among A. uncatus populations changed markedly both temporally and spatially in response to the extreme climate event in 2003. Our results highlight the magnitude of temporal population genetic changes in response to extreme events. More specifically, our results show that extreme events can cause rapid genetic divergence in metapopulations. Further studies are needed to determine if recovery from this perturbation through gradual mixing of diverged populations by

  10. Optimizing Urban Material Flows and Waste Streams in Urban Development through Principles of Zero Waste and Sustainable Consumption

    Directory of Open Access Journals (Sweden)

    Steffen Lehmann

    2011-01-01

    designers, industrial designers, and so on. How must urban development and construction change and evolve to automatically embed sustainability in the way we design, build, operate, maintain and renew/recycle cities? One of the findings of this paper is that embedding zero-waste requires strong industry leadership, new policies and effective education curricula, as well as raising awareness (through research and education and refocusing research agendas to bring about attitudinal change and the reduction of wasteful consumption.

  11. Preparation and optimization of sustained release matrix tablets of metoprolol succinate and taro gum using response surface methodology

    Directory of Open Access Journals (Sweden)

    M. Soumya

    2014-01-01

    Full Text Available In the present study, an effort was made to formulate and evaluate matrix tablets of tarogum utilizing metaprolol succinate as the model drug. 3 2 full optimization procedure was adopted where two factors are studied at three levels. The amount of taro gum (X1 and polyvinylpyrrolidone (PVP K30 (X2 were selected as independent variables. The time required for 90% of drug release was selected as the dependent variable. Tablets were prepared by direct compression and were evaluated for various post compression parameters such as tablet hardness, friability, weight variation, drug content and in vitro dissolution. The results were found to be within the acceptable limits. The release exponent (n lies between 0.416 and 0.584 indicating drug release from the matrix tablets may be fickian or non-fickian (anomalous depending upon the concentration of natural polymer. T90 was 10.70, 11.20, 12.05, 12.66 h for B6, B7, B8 and B9 batches respectively showing overriding potential of taro gum, but still the effect of PVP K 30 is noteworthy. PVP K 30 has an indirect effect on all the factors by increasing tensile strength and making the tablet firm and intact.

  12. A modeling framework for integrated harvest and habitat management of North American waterfowl: Case-study of northern pintail metapopulation dynamics

    Science.gov (United States)

    Mattsson, Brady J.; Runge, M.C.; Devries, J.H.; Boomer, G.S.; Eadie, J.M.; Haukos, D.A.; Fleskes, J.P.; Koons, D.N.; Thogmartin, W.E.; Clark, R.G.

    2012-01-01

    We developed and evaluated the performance of a metapopulation model enabling managers to examine, for the first time, the consequences of alternative management strategies involving habitat conditions and hunting on both harvest opportunity and carrying capacity (i.e., equilibrium population size in the absence of harvest) for migratory waterfowl at a continental scale. Our focus is on the northern pintail (Anas acuta; hereafter, pintail), which serves as a useful model species to examine the potential for integrating waterfowl harvest and habitat management in North America. We developed submodel structure capturing important processes for pintail populations during breeding, fall migration, winter, and spring migration while encompassing spatial structure representing three core breeding areas and two core nonbreeding areas. A number of continental-scale predictions from our baseline parameterization (e.g., carrying capacity of 5.5 million, equilibrium population size of 2.9 million and harvest rate of 12% at maximum sustained yield [MSY]) were within 10% of those from the pintail harvest strategy under current use by the U.S. Fish and Wildlife Service. To begin investigating the interaction of harvest and habitat management, we examined equilibrium population conditions for pintail at the continental scale across a range of harvest rates while perturbing model parameters to represent: (1) a 10% increase in breeding habitat quality in the Prairie Pothole population (PR); and (2) a 10% increase in nonbreeding habitat quantity along in the Gulf Coast (GC). Based on our model and analysis, a greater increase in carrying capacity and sustainable harvest was seen when increasing a proxy for habitat quality in the Prairie Pothole population. This finding and underlying assumptions must be critically evaluated, however, before specific management recommendations can be made. To make such recommendations, we require (1) extended, refined submodels with additional

  13. Survival differences and the effect of environmental instability on breeding dispersal in an Adelie penguin meta-population.

    Science.gov (United States)

    Dugger, Katie M; Ainley, David G; Lyver, Phil O'B; Barton, Kerry; Ballard, Grant

    2010-07-06

    High survival and breeding philopatry was previously confirmed for the Adélie penguin (Pygoscelis adeliae) during a period of stable environmental conditions. However, movements of breeding adults as a result of an unplanned natural experiment within a four-colony meta-population provided interesting insights into this species' population dynamics. We used multistate mark-recapture models to investigate apparent survival and dispersal of breeding birds in the southwestern Ross Sea during 12 breeding seasons (1996-2007). The natural experiment was facilitated by the temporary grounding of two immense icebergs that (i) erected a veritable fence separating colonies and altering migration routes and (ii) added additional stress by trapping extensive sea ice in the region during 5 of 12 y. Colony size varied by orders of magnitude, allowing investigation of apparent survival and dispersal rates in relation to both environmental conditions and colony size within this meta-population. Apparent survival was lowest for the smallest colony (4,000 pairs) and similar for the medium (45,000 pairs) and large colonies (155,000 pairs), despite increased foraging effort expended by breeders at the largest colony. Dispersal of breeding birds was low (population. Contrary to current thought, breeding penguins are not always philopatric. Rather, stressful conditions can significantly increase dispersal rates.

  14. Zoos through the lens of the IUCN Red List: a global metapopulation approach to support conservation breeding programs.

    Science.gov (United States)

    Conde, Dalia A; Colchero, Fernando; Gusset, Markus; Pearce-Kelly, Paul; Byers, Onnie; Flesness, Nate; Browne, Robert K; Jones, Owen R

    2013-01-01

    Given current extinction trends, the number of species requiring conservation breeding programs (CBPs) is likely to increase dramatically. To inform CBP policies for threatened terrestrial vertebrates, we evaluated the number and representation of threatened vertebrate species on the IUCN Red List held in the ISIS zoo network and estimated the complexity of their management as metapopulations. Our results show that 695 of the 3,955 (23%) terrestrial vertebrate species in ISIS zoos are threatened. Only two of the 59 taxonomic orders show a higher proportion of threatened species in ISIS zoos than would be expected if species were selected at random. In addition, for most taxa, the management of a zoo metapopulation of more than 250 individuals will require the coordination of a cluster of 11 to 24 ISIS zoos within a radius of 2,000 km. Thus, in the zoo network, the representation of species that may require CBPs is currently low and the spatial distribution of these zoo populations makes management difficult. Although the zoo community may have the will and the logistical potential to contribute to conservation actions, including CBPs, to do so will require greater collaboration between zoos and other institutions, alongside the development of international agreements that facilitate cross-border movement of zoo animals. To maximize the effectiveness of integrated conservation actions that include CBPs, it is fundamental that the non-zoo conservation community acknowledges and integrates the expertise and facilities of zoos where it can be helpful.

  15. Zoos through the lens of the IUCN Red List: a global metapopulation approach to support conservation breeding programs.

    Directory of Open Access Journals (Sweden)

    Dalia A Conde

    Full Text Available Given current extinction trends, the number of species requiring conservation breeding programs (CBPs is likely to increase dramatically. To inform CBP policies for threatened terrestrial vertebrates, we evaluated the number and representation of threatened vertebrate species on the IUCN Red List held in the ISIS zoo network and estimated the complexity of their management as metapopulations. Our results show that 695 of the 3,955 (23% terrestrial vertebrate species in ISIS zoos are threatened. Only two of the 59 taxonomic orders show a higher proportion of threatened species in ISIS zoos than would be expected if species were selected at random. In addition, for most taxa, the management of a zoo metapopulation of more than 250 individuals will require the coordination of a cluster of 11 to 24 ISIS zoos within a radius of 2,000 km. Thus, in the zoo network, the representation of species that may require CBPs is currently low and the spatial distribution of these zoo populations makes management difficult. Although the zoo community may have the will and the logistical potential to contribute to conservation actions, including CBPs, to do so will require greater collaboration between zoos and other institutions, alongside the development of international agreements that facilitate cross-border movement of zoo animals. To maximize the effectiveness of integrated conservation actions that include CBPs, it is fundamental that the non-zoo conservation community acknowledges and integrates the expertise and facilities of zoos where it can be helpful.

  16. Genetic Variation, Structure, and Gene Flow in a Sloth Bear (Melursus ursinus Meta-Population in the Satpura-Maikal Landscape of Central India.

    Directory of Open Access Journals (Sweden)

    Trishna Dutta

    Full Text Available Sloth bears (Melursus ursinus are endemic to the Indian subcontinent. As a result of continued habitat loss and degradation over the past century, sloth bear populations have been in steady decline and now exist only in isolated or fragmented habitat across the entire range. We investigated the genetic connectivity of the sloth bear meta-population in five tiger reserves in the Satpura-Maikal landscape of central India. We used noninvasively collected fecal and hair samples to obtain genotypic information using a panel of seven polymorphic loci. Out of 194 field collected samples, we identified 55 individuals in this meta-population. We found that this meta-population has moderate genetic variation, and is subdivided into two genetic clusters. Further, we identified five first-generation migrants and signatures of contemporary gene flow. We found evidence of sloth bears in the corridor between the Kanha and Pench Tiger Reserves, and our results suggest that habitat connectivity and corridors play an important role in maintaining gene flow in this meta-population. These corridors face several anthropogenic and infrastructure development threats that have the potential to sever ongoing gene flow, if policies to protect them are not put into action immediately.

  17. Genetic Variation, Structure, and Gene Flow in a Sloth Bear (Melursus ursinus) Meta-Population in the Satpura-Maikal Landscape of Central India.

    Science.gov (United States)

    Dutta, Trishna; Sharma, Sandeep; Maldonado, Jesús E; Panwar, Hemendra Singh; Seidensticker, John

    2015-01-01

    Sloth bears (Melursus ursinus) are endemic to the Indian subcontinent. As a result of continued habitat loss and degradation over the past century, sloth bear populations have been in steady decline and now exist only in isolated or fragmented habitat across the entire range. We investigated the genetic connectivity of the sloth bear meta-population in five tiger reserves in the Satpura-Maikal landscape of central India. We used noninvasively collected fecal and hair samples to obtain genotypic information using a panel of seven polymorphic loci. Out of 194 field collected samples, we identified 55 individuals in this meta-population. We found that this meta-population has moderate genetic variation, and is subdivided into two genetic clusters. Further, we identified five first-generation migrants and signatures of contemporary gene flow. We found evidence of sloth bears in the corridor between the Kanha and Pench Tiger Reserves, and our results suggest that habitat connectivity and corridors play an important role in maintaining gene flow in this meta-population. These corridors face several anthropogenic and infrastructure development threats that have the potential to sever ongoing gene flow, if policies to protect them are not put into action immediately.

  18. Influence of some formulation variables on the optimization of pH-dependent, colon-targeted, sustained-release mesalamine microspheres.

    Science.gov (United States)

    El-Bary, Ahmed Abd; Aboelwafa, Ahmed A; Al Sharabi, Ibrahim M

    2012-03-01

    The aim of this work was to understand the influence of different formulation variables on the optimization of pH-dependent, colon-targeted, sustained-release mesalamine microspheres prepared by O/O emulsion solvent evaporation method, employing pH-dependent Eudragit S and hydrophobic pH-independent ethylcellulose polymers. Formulation variables studied included concentration of Eudragit S in the internal phase and the ratios between; internal to external phase, drug to Eudragit S and Eudragit S to ethylcellulose to mesalamine. Prepared microspheres were evaluated by carrying out in vitro release studies and determination of particle size, production yield, and encapsulation efficiency. In addition, morphology of microspheres was examined using optical and scanning electron microscopy. Emulsion solvent evaporation method was found to be sensitive to the studied formulation variables. Particle size and encapsulation efficiency increased by increasing Eudragit S concentration in the internal phase, ratio of internal to external phase, and ratio of Eudragit S to the drug. Employing Eudragit S alone in preparation of the microspheres is only successful in forming acid-resistant microspheres with pulsatile release pattern at high pH. Eudragit S and ethylcellulose blend microspheres were able to control release under acidic condition and to extend drug release at high pH. The stability studies carried out at 40°C/75% RH for 6 months proved the stability of the optimized formulation. From the results of this investigation, microencapsulation of mesalamine in microspheres using blend of Eudragit S and ethylcellulose could constitute a promising approach for site-specific and controlled delivery of drug in colon.

  19. Optimal Cropping Pattern Based on Multiple Economic, Regional, and Agricultural Sustainability Criteria in Sari, Iran: Application of a Consolidated Model of AHP and Linear Programming

    Directory of Open Access Journals (Sweden)

    E. Fallahi

    2016-10-01

    Full Text Available Introduction: Determining a suitable cropping pattern is an important task for planners and requires an exact and realistic decision-making process based on several goals and criteria corresponding to secure the interest of agricultural beneficiaries in long-term. Accordingly, this study reviews the current pattern operated by farmers in Sari, Iran, and intends to provide a cropping pattern that considers the multifold regional and agricultural sustainability criteria along with economic considerations. Materials and Methods: In order to achieve the study goals, a consolidated model of AHP and Linear Programming was applied. For this purpose, we constructed a three-level AHP, including a goal (determining the weight of each crop, seven criteria, and seven alternatives. Profitability, compatibility with regional and geographical conditions, water consumption, environmental effects of cropping, job creation opportunities, skill and proficiency required for producing a crop, and risk taken to cultivate a crop were considered as the criteria in the model. Seven alternative crops including rice, wheat, rapeseed, barley, soybean, clover, and vegetables were considered too. The next step is determining the weight of each criterion with regard to the goal and the weight of each alternative with regard to each criteria. By multiplying these weights, final weights for various crops were obtained from the model. Derived weights for each crop were then applied as objective function coefficients in the Linear Programming model and the model was solved subject to the constraints. Results and Discussion: Optimal cropping pattern determined based on the consolidated model of AHP and Linear Programming and the results compared to a scenario that only looks forward to maximizing the economic interests. Due to the low profitability of rapeseed and barley, these crops eliminated from the pattern in the profit-maximizing scenario. According to the results, the

  20. Optimal Control of a Spatio-Temporal Model for Malaria: Synergy Treatment and Prevention

    Directory of Open Access Journals (Sweden)

    Malicki Zorom

    2012-01-01

    Full Text Available We propose a metapopulation model for malaria with two control variables, treatment and prevention, distributed between different patches (localities. Malaria spreads between these localities through human travel. We used the theory of optimal control and applied a mathematical model for three connected patches. From previous studies with the same data, two patches were identified as reservoirs of malaria infection, namely, the patches that sustain malaria epidemic in the other patches. We argue that to reduce the number of infections and semi-immunes (i.e., asymptomatic carriers of parasites in overall population, two considerations are needed, (a For the reservoir patches, we need to apply both treatment and prevention to reduce the number of infections and to reduce the number of semi-immunes; neither the treatment nor prevention were specified at the beginning of the control application, except prevention that seems to be effective at the end. (b For unreservoir patches, we should apply the treatment to reduce the number of infections, and the same strategy should be applied to semi-immune as in (a.

  1. Biophysical constraints on optimal patch lengths for settlement of a reef-building bivalve.

    Directory of Open Access Journals (Sweden)

    Heidi L Fuchs

    Full Text Available Reef-building species form discrete patches atop soft sediments, and reef restoration often involves depositing solid material as a substrate for larval settlement and growth. There have been few theoretical efforts to optimize the physical characteristics of a restored reef patch to achieve high recruitment rates. The delivery of competent larvae to a reef patch is influenced by larval behavior and by physical habitat characteristics such as substrate roughness, patch length, current speed, and water depth. We used a spatial model, the "hitting-distance" model, to identify habitat characteristics that will jointly maximize both the settlement probability and the density of recruits on an oyster reef (Crassostrea virginica. Modeled larval behaviors were based on laboratory observations and included turbulence-induced diving, turbulence-induced passive sinking, and neutral buoyancy. Profiles of currents and turbulence were based on velocity profiles measured in coastal Virginia over four different substrates: natural oyster reefs, mud, and deposited oyster and whelk shell. Settlement probabilities were higher on larger patches, whereas average settler densities were higher on smaller patches. Larvae settled most successfully and had the smallest optimal patch length when diving over rough substrates in shallow water. Water depth was the greatest source of variability, followed by larval behavior, substrate roughness, and tidal current speed. This result suggests that the best way to maximize settlement on restored reefs is to construct patches of optimal length for the water depth, whereas substrate type is less important than expected. Although physical patch characteristics are easy to measure, uncertainty about larval behavior remains an obstacle for predicting settlement patterns. The mechanistic approach presented here could be combined with a spatially explicit metapopulation model to optimize the arrangement of reef patches in an estuary

  2. Critical paths in a metapopulation model of H1N1: Efficiently delaying influenza spreading through flight cancellation

    CERN Document Server

    Marcelino, Jose; 10.1371/4f8c9a2e1fca8

    2012-01-01

    Disease spreading through human travel networks has been a topic of great interest in recent years, as witnessed during outbreaks of influenza A (H1N1) or SARS pandemics. One way to stop spreading over the airline network are travel restrictions for major airports or network hubs based on the total number of passengers of an airport. Here, we test alternative strategies using edge removal, cancelling targeted flight connections rather than restricting traffic for network hubs, for controlling spreading over the airline network. We employ a SEIR metapopulation model that takes into account the population of cities, simulates infection within cities and across the network of the top 500 airports, and tests different flight cancellation methods for limiting the course of infection. The time required to spread an infection globally, as simulated by a stochastic global spreading model was used to rank the candidate control strategies. The model includes both local spreading dynamics at the level of populations and...

  3. A seasonal SIR metapopulation model with an Allee effect with application to controlling plague in prairie dog colonies.

    Science.gov (United States)

    Ekanayake, A J; Ekanayake, D B

    2015-01-01

    For wildlife species living among patchy habitats, disease and the Allee effect (reduced per capita birth rates at low population densities) may together drive a patch's population to extinction, particularly if births are seasonal. Yet local extinction may not be indicative of global extinction, and a patch may become recolonized by migrating individuals. We introduce deterministic and stochastic susceptible, infectious, and immune epidemic models with vector species to study disease in a metapopulation with an Allee effect and seasonal birth and dispersal. We obtain conditions for the existence of a strong Allee effect and existence and stability of a disease-free positive periodic solution. These general models have application to many wildlife diseases. As a case study, we apply them to evaluate dynamics of the sylvatic plague in prairie dog colonies interconnected through dispersal. We further evaluate the effects of control of the vector population and control by immunization on plague eradication.

  4. Climate change winners: receding ice fields facilitate colony expansion and altered dynamics in an Adélie penguin metapopulation

    Science.gov (United States)

    LaRue, Michelle A.; Ainley, David G.; Swanson, Matt; Dugger, Katie M.; Lyber, Phil O'B.; Barton, Kerry; Ballard, Grant

    2013-01-01

    There will be winners and losers as climate change alters the habitats of polar organisms. For an Adélie penguin (Pygoscelis adeliae) colony on Beaufort Island (Beaufort), part of a cluster of colonies in the southern Ross Sea, we report a recent population increase in response to increased nesting habitat as glaciers have receded. Emigration rates of birds banded as chicks on Beaufort to colonies on nearby Ross Island decreased after 2005 as available habitat on Beaufort increased, leading to altered dynamics of the metapopulation. Using aerial photography beginning in 1958 and modern satellite imagery, we measured change in area of available nesting habitat and population size of the Beaufort colony. Population size varied with available habitat, and both increased rapidly since the 1990s. In accord with glacial retreat, summer temperatures at nearby McMurdo Station increased by ~0.50°C per decade since the mid-1980s. Although the Ross Sea is likely to be the last ocean with an intact ecosystem, the recent retreat of ice fields at Beaufort that resulted in increased breeding habitat exemplifies a process that has been underway in the Ross Sea during the entire Holocene. Furthermore, our results are in line with predictions that major ice shelves and glaciers will retreat rapidly elsewhere in the Antarctic, potentially leading to increased breeding habitat for Adélie penguins. Results further indicated that satellite imagery may be used to estimate large changes in Adélie penguin populations, facilitating our understanding of metapopulation dynamics and environmental factors that influence regional populations.

  5. Climate change winners: receding ice fields facilitate colony expansion and altered dynamics in an Adelie penguin metapopulation.

    Directory of Open Access Journals (Sweden)

    Michelle A LaRue

    Full Text Available There will be winners and losers as climate change alters the habitats of polar organisms. For an Adélie penguin (Pygoscelis adeliae colony on Beaufort Island (Beaufort, part of a cluster of colonies in the southern Ross Sea, we report a recent population increase in response to increased nesting habitat as glaciers have receded. Emigration rates of birds banded as chicks on Beaufort to colonies on nearby Ross Island decreased after 2005 as available habitat on Beaufort increased, leading to altered dynamics of the metapopulation. Using aerial photography beginning in 1958 and modern satellite imagery, we measured change in area of available nesting habitat and population size of the Beaufort colony. Population size varied with available habitat, and both increased rapidly since the 1990s. In accord with glacial retreat, summer temperatures at nearby McMurdo Station increased by ~0.50 °C per decade since the mid-1980s. Although the Ross Sea is likely to be the last ocean with an intact ecosystem, the recent retreat of ice fields at Beaufort that resulted in increased breeding habitat exemplifies a process that has been underway in the Ross Sea during the entire Holocene. Furthermore, our results are in line with predictions that major ice shelves and glaciers will retreat rapidly elsewhere in the Antarctic, potentially leading to increased breeding habitat for Adélie penguins. Results further indicated that satellite imagery may be used to estimate large changes in Adélie penguin populations, facilitating our understanding of metapopulation dynamics and environmental factors that influence regional populations.

  6. A metapopulation model to assess the capacity of spread of meticillin-resistant Staphylococcus aureus ST398 in humans.

    Directory of Open Access Journals (Sweden)

    Thibaud Porphyre

    Full Text Available The emergence of the livestock-associated clone of meticillin-resistant Staphylococcus aureus (MRSA ST398 is a serious public health issue throughout Europe. In The Netherlands a stringent 'search-and-destroy' policy has been adopted, keeping low the level of MRSA prevalence. However, reports have recently emerged of transmission events between humans showing no links to livestock, contradicting belief that MRSA ST398 is poorly transmissible in humans. The question regarding the transmissibility of MRSA ST398 in humans therefore remains of great interest. Here, we investigated the capacity of MRSA ST398 to spread into an entirely susceptible human population subject to the effect of a single MRSA-positive commercial pig farm. Using a stochastic, discrete-time metapopulation model, we explored the effect of varying both the probability of persistent carriage and that of acquiring MRSA due to contact with pigs on the transmission dynamics of MRSA ST398 in humans. In particular, we assessed the value and key determinants of the basic reproduction ratio (R(0 for MRSA ST398. Simulations showed that the presence of recurrent exposures with pigs in risky populations allows MRSA ST398 to persist in the metapopulation and transmission events to occur beyond the farming community, even when the probability of persistent carriage is low. We further showed that persistent carriage should occur in less than 10% of the time for MRSA ST398 to conserve epidemiological characteristics similar to what has been previously reported. These results indicate that implementing control policy that only targets human carriers may not be sufficient to control MRSA ST398 in the community if it remains in pigs. We argue that farm-level control measures should be implemented if an eradication programme is to be considered.

  7. Optimized Model of Passenger Structure Based on Urban Transportation Sustainability%基于城市交通可持续性的客运结构优化模型

    Institute of Scientific and Technical Information of China (English)

    沈嘉曦; 王培恒

    2014-01-01

    Based on the social sustainability , economical sustainability and environmental sustainability , the optimized model of the urban passenger transportation structure is established by maximizing the social efficiency and minimizing the internal cost of transportation system and its environmental influence .In addition, the model is calculated by using the ideal point of the multiple plans .In the article, the city of Chengdu is used as an example to verify the practicability and correctness of the model and the optimized passenger structure reflects the sustainable development goal of the urban transportation .%基于社会可持续性、经济可持续性和环境可持续性3个方面的交通可持续性,以交通系统的社会效率最大化和交通系统内部成本以及环境影响最小化为约束,构建城市客运交通结构优化模型并进行优化,并利用多目标规划中的理想点法求解模型。以成都市为例,验证了模型的可行性与正确性,优化后的客运结构体现了城市可持续交通的发展目标。

  8. Research on the Sustainable Development of the Optimal Allocation of Water Resources%面向可持续发展的水资源优化配置研究

    Institute of Scientific and Technical Information of China (English)

    李丽琴; 谢新民; 韩剑桥; 吕自鑫; 杜明月

    2013-01-01

    According to the relationship between the sustainable development and the optimal allocation of water resources, the evaluation system based on the sustainable development of optimal allocation of water resources is established in respect of the index system water resources carrying capacity, and the social economic and ecological environment. Then, based on the method of the membership degree calculation of engineering fuzzy set theory, sustainable degree and sustainable development ability are measured. Shanshan County is taken as an example to evaluate the sustainable degree with actual index value from the regional water resources supply and demand balance of simulation results. It is found that the sustainable degree of Shanshan County increases gradually with the increase in planning level years (2015, 2020, and 2030). In 2030 the sustainable degree will reach 0. 74, which is in the higher level of sustainable development The countermeasures of sustainable development based on multi-objective are suggested.%结合可持续发展与水资源优化配置的关系,从水资源承载能力、经济社会和生态环境指标体系三方面建立了基于可持续发展的水资源优化配置的评价体系.以工程模糊集理论中的隶属度计算方法为基础,进行评价因子可持续度的计算,衡量区域可持续发展能力.以鄯善县为例,采用区域水资源供需平衡的模拟计算结果,作为指标评价体系的实际指标值,进行鄯善县水资源配置可持续度的评判.结果表明:鄯善县的可持续度随着规划水平年(2015、2020、2030年)的延续而逐渐增大.2030年鄯善县可持续度达到0.74,处于中上级可持续发展水平.最后给出了鄯善县多目标协同可持续发展的策略.

  9. MetaPIGA v2.0: maximum likelihood large phylogeny estimation using the metapopulation genetic algorithm and other stochastic heuristics

    Directory of Open Access Journals (Sweden)

    Milinkovitch Michel C

    2010-07-01

    Full Text Available Abstract Background The development, in the last decade, of stochastic heuristics implemented in robust application softwares has made large phylogeny inference a key step in most comparative studies involving molecular sequences. Still, the choice of a phylogeny inference software is often dictated by a combination of parameters not related to the raw performance of the implemented algorithm(s but rather by practical issues such as ergonomics and/or the availability of specific functionalities. Results Here, we present MetaPIGA v2.0, a robust implementation of several stochastic heuristics for large phylogeny inference (under maximum likelihood, including a Simulated Annealing algorithm, a classical Genetic Algorithm, and the Metapopulation Genetic Algorithm (metaGA together with complex substitution models, discrete Gamma rate heterogeneity, and the possibility to partition data. MetaPIGA v2.0 also implements the Likelihood Ratio Test, the Akaike Information Criterion, and the Bayesian Information Criterion for automated selection of substitution models that best fit the data. Heuristics and substitution models are highly customizable through manual batch files and command line processing. However, MetaPIGA v2.0 also offers an extensive graphical user interface for parameters setting, generating and running batch files, following run progress, and manipulating result trees. MetaPIGA v2.0 uses standard formats for data sets and trees, is platform independent, runs in 32 and 64-bits systems, and takes advantage of multiprocessor and multicore computers. Conclusions The metaGA resolves the major problem inherent to classical Genetic Algorithms by maintaining high inter-population variation even under strong intra-population selection. Implementation of the metaGA together with additional stochastic heuristics into a single software will allow rigorous optimization of each heuristic as well as a meaningful comparison of performances among these

  10. Administration of colistin sulfate in endotoxic model at slow and sustained fashion may reverse shock without causing nephrotoxicity in its optimal concentration.

    Science.gov (United States)

    Haque, Anwarul; Ishii, Yoshikazu; Akasaka, Yoshikiyo; Matsumoto, Tetsuya; Tateda, Kazuhiro

    2017-07-31

    Despite of proven LPS neutralizing activity, intravenous polymyxin use was waned due to experience of associated nephrotoxicity. But, increasing resistance to all available antibiotics has necessitated their resurgence and the prodrug of colistin sulfate (CS), known as colistin-methanesulfonate (CMS), is increasingly used as the only therapeutic option in many infections. Currently available CMS employ very different dose definitions and thus because of complex pharmacokinetics/pharmacodynamics information and short half-life, this drug use remains confusing. We aimed to expose CS in endotoxic shock models by micro-osmotic pump and evaluated its effectiveness. We used micro-osmotic pumps to deliver either sterile saline or CS at different dosages ranging from 0.25mg/day to 7mg/day for consecutive 3days in LPS (8mg/kg body weight) induced endotoxic mice and observed their outcome twice daily for a week to determine the survival rate. Serum pro-inflammatory cytokine levels and apoptosis in renal tissues in these models were evaluated. We showed endotoxic shock was reversed and all mice survived with a CS administration at a dosage of 2mg/day for 3 days, in comparison to survival rate with saline administration (p=<0.0001) in endotoxic models. CS infusion in shock models using micro-osmotic pump ameliorated rising of serum TNF-α, IL-12p70 and IL-6 levels. Nephrotoxicity was evident only with a higher dosage, but not with a lower dosage which was optimum to control endotoxic shock in models. These results highlighted that an optimal dosage of CS effectively improved outcome in endotoxic shock models without causing nephrotoxicity when administered at a slow and sustained manner. And a higher CS dosage administration was nephrotoxic and fatal. Thus this study bought an opportunity to consider future investigations with CS administration in murine Gram-negative bacterial infections in a novel way. Copyright © 2017 International Society for Chemotherapy of Infection and

  11. Sustainable Housing Design

    DEFF Research Database (Denmark)

    Lauring, Gert Michael

    2016-01-01

    Sustainable Housing Design. Integrating technical and housing quality aspects of sustainable architecture in civil engineering education. Summary An integrated design approach to sustainable architecture is outlined that combines concerns for zero energy building, good indoor climate and adequate...... phases. The outcome shows that integrated design further solutions where sustainable urban forms of settlement can be highly energy efficient while also attractive from a user perspective. Key words: Sustainable architecture, integrated design, zero-energy-housing, dense urban living. 1. Introduction...... constructions, private and public outdoor space, housing, urban and architectural quality. The educational framework, curriculum and inte-grated design methods are preconditions for optimizing a design process where technical criteria, functional concerns and housing quality are addressed from the initial...

  12. The development of a new district heating concept: Network design and optimization for integrating energy conservation and renewable energy use in energy sustainable communities

    Energy Technology Data Exchange (ETDEWEB)

    Dalla Rosa, A.

    2012-07-01

    elements of LTDH networks, particularly when supplying low heat density building areas. The purpose of article IV was to perform simulations and analyses about low-energy DH networks supplying heat to energy-efficient building areas in countries such as Denmark with an extensive existing DH infrastructure, quantify their technical and economic feasibility, and suggest strategies for optimizing their design and operation. Article V deals with the potential and barriers of implementing DH in Canada, where the DH market share is low. Technical-economic feasibility studies for DH networks supplying an urban area in the city of Ottawa were carried out, with particular attention to developing the potential for supplying heat derived from Renewable Energy (RE). Chapter 6 summarises the conclusions. First of all, analysis of the case studies suggests that local authority energy plans should take the opportunities for DH implementation into account, because DH is an essential infrastructure for future, sustainable energy systems. Energy policy should aim at organizing and facilitating the synergy between energy conservation measures and the supply of heat based on RE energy and overcome the traditional competition between the two sectors. It is recommended that Finite Element Method (FEM) models and simulation should be used when designing new pipe geometries and systems. The reliability of the FEM models of DH pipes was validated by means of experimental data and comparison with analytical formulas and data from literature. The calculation method takes into account the temperature-dependency of the thermal conductivity of the insulation foam. It was demonstrated that the asymmetrical insulation of twin pipes in lowtemperature operations leads to 4% to 8% lower heat loss from the supply media pipe than a symmetrical configuration, and at the same time the heat loss from the return media pipe can be kept close to zero. With the use of optimized double-pipe systems (a pair of

  13. Sustainable Museums for Sustainable Development

    OpenAIRE

    Pop, Izabela Luiza; Borza, Anca

    2015-01-01

    The sustainable development of a region depends on the sustainability and measures taken by all the public and private organizations in the respective area. Museums stand out among these organizations due to the controversies arising in connection with the role they have to play in this process of sustainable development. This paper seeks to analyze whether and why museums should become sustainable and provide an overview on the Romanian museums’ sustainability. The qualitative research based...

  14. Sustainable consumption

    DEFF Research Database (Denmark)

    Prothero, Andrea; Dobscha, Susan; Freund, Jim

    2011-01-01

    This essay explores sustainable consumption and considers possible roles for marketing and consumer researchers and public policy makers in addressing the many sustainability challenges that pervade our planet. Future research approaches to this interdisciplinary topic need to be comprehensive...

  15. Formulation Optimization of Sustained-Release Ammonio Methacrylate Copolymer Microspheres. Effects of Log P and Concentration of Polar Cosolvents, and Role of the Drug/Copolymer Ratio

    Directory of Open Access Journals (Sweden)

    Piroska Szabó-Révész

    2011-11-01

    Full Text Available The objectives of this work were the formulation optimization of the preparation process parameters and to evaluate spray-dried sustained-release microspheres using ammonio methacrylate copolymer (AMC as a polymer matrix. The effects of log P and the concentrations of the cosolvents (acetone, methyl ethyl ketone and n-butyl acetate and different drug/copolymer ratios as independent variables on the physicochemical parameters (the W1/O emulsion viscosity, the microsphere production yield, the average particle size, the encapsulation efficiency and the cumulative in vitro drug release as dependent variables were studied. The optimization was carried out on the basis of the 33 factorial design study. The optimization process results showed that addition of polar cosolvents proved effective, linear relationships were observed between the independent and the dependent variables. The best conditions were achieved by microspheres prepared by using a low/medium cosolvent log P, cosolvent concentration of 25–50% v/v and a drug/copolymer ratio of 1:16. The microspheres ensured sustained release with Nernst and Baker-Lonsdale release profiles.

  16. High genetic variation in resting-stage production in a metapopulation: Is there evidence for local adaptation?

    Science.gov (United States)

    Roulin, Anne C; Mariadassou, Mahendra; Hall, Matthew D; Walser, Jean-Claude; Haag, Christoph; Ebert, Dieter

    2015-10-01

    Local adaptation is a key process for the maintenance of genetic diversity and population diversification. A better understanding of the mechanisms that allow (or prevent) local adaptation constitutes a key in apprehending how and at what spatial scale it occurs. The production of resting stages is found in many taxa and reflects an adaptation to outlast adverse environmental conditions. Daphnia magna (Crustacea) can alternate between asexual and sexual reproduction, the latter being linked to dormancy, as resting stages can only be produced sexually. In this species, on a continental scale, resting-stage production is locally adapted--that is, it is induced when the photoperiod indicates the imminence of habitat deterioration. Here, we aimed to explore whether selection is strong enough to maintain local adaptation at a scale of a few kilometers. We assessed life-history traits of 64 D. magna clones originating from 11 populations of a metapopulation with permanent and intermittent pool habitats. We found large within- and between-population variation for all dormancy-related traits, but no evidence for the hypothesized higher resting-stage production in animals from intermittent habitats. We discuss how gene flow, founder events, or other forms of selection might interfere with the process of local adaptation.

  17. Paternal transmission of mitochondrial DNA as an integral part of mitochondrial inheritance in metapopulations of Drosophila simulans.

    Science.gov (United States)

    Wolff, J N; Nafisinia, M; Sutovsky, P; Ballard, J W O

    2013-01-01

    Maternal inheritance is one of the hallmarks of animal mitochondrial DNA (mtDNA) and central to its success as a molecular marker. This mode of inheritance and subsequent lack of heterologous recombination allows us to retrace evolutionary relationships unambiguously down the matriline and without the confounding effects of recombinant genetic information. Accumulating evidence of biparental inheritance of mtDNA (paternal leakage), however, challenges our current understanding of how this molecule is inherited. Here, using Drosophila simulans collected from an East African metapopulation exhibiting recurring mitochondrial heteroplasmy, we conducted single fly matings and screened F1 offspring for the presence of paternal mtDNA using allele-specific PCR assays (AS-PCR). In all, 27 out of 4092 offspring were identified as harboring paternal mtDNA, suggesting a frequency of 0.66% paternal leakage in this species. Our findings strongly suggest that recurring mtDNA heteroplasmy as observed in natural populations of Drosophila simulans is most likely caused by repeated paternal leakage. Our findings further suggest that this phenomenon to potentially be an integral part of mtDNA inheritance in these populations and consequently of significance for mtDNA as a molecular marker.

  18. The implications of habitat management on the population viability of the endangered Ohlone tiger beetle (Cicindela ohlone metapopulation.

    Directory of Open Access Journals (Sweden)

    Tara M Cornelisse

    Full Text Available Despite their role in providing ecosystem services, insects remain overlooked in conservation planning, and insect management approaches often lack a rigorous scientific basis. The endangered Ohlone tiger beetle (Cicindela ohlone occurs in a 24-km(2 area in Santa Cruz County, California. The once larger metapopulation now consists of subpopulations inhabiting five patches of coastal prairie where it depends on bare ground for mating, foraging, and oviposition. Human activities have eliminated natural disturbances and spread invasive grasses, reducing C. ohlone's bare-ground habitat. Management actions to restore critical beetle habitat consist of cattle and horse grazing, maintaining slow bicycle speeds on occupied public trails, and artificial creation of bare-ground plots. Recreational biking trails help maintain bare ground, but can cause beetle mortality if left unregulated. We tracked C. ohlone survivorship and estimated fecundity for three years. We then constructed a stage-structured population projection matrix model to estimate population viability among the five patches, and to evaluate the success of management interventions. We demonstrate that habitat creation, regulation of bicycle speed, and migration between patches increase C. ohlone survival and population viability. Our results can be directly applied to management actions for conservation outcomes that will reduce species extinction risk and promote recolonization of extirpated patches.

  19. The implications of habitat management on the population viability of the endangered Ohlone tiger beetle (Cicindela ohlone) metapopulation.

    Science.gov (United States)

    Cornelisse, Tara M; Bennett, Michelle K; Letourneau, Deborah K

    2013-01-01

    Despite their role in providing ecosystem services, insects remain overlooked in conservation planning, and insect management approaches often lack a rigorous scientific basis. The endangered Ohlone tiger beetle (Cicindela ohlone) occurs in a 24-km(2) area in Santa Cruz County, California. The once larger metapopulation now consists of subpopulations inhabiting five patches of coastal prairie where it depends on bare ground for mating, foraging, and oviposition. Human activities have eliminated natural disturbances and spread invasive grasses, reducing C. ohlone's bare-ground habitat. Management actions to restore critical beetle habitat consist of cattle and horse grazing, maintaining slow bicycle speeds on occupied public trails, and artificial creation of bare-ground plots. Recreational biking trails help maintain bare ground, but can cause beetle mortality if left unregulated. We tracked C. ohlone survivorship and estimated fecundity for three years. We then constructed a stage-structured population projection matrix model to estimate population viability among the five patches, and to evaluate the success of management interventions. We demonstrate that habitat creation, regulation of bicycle speed, and migration between patches increase C. ohlone survival and population viability. Our results can be directly applied to management actions for conservation outcomes that will reduce species extinction risk and promote recolonization of extirpated patches.

  20. Temporal and spatial variation in prevalence of the parasite Syngamus trachea in a metapopulation of house sparrows (Passer domesticus).

    Science.gov (United States)

    Holand, Håkon; Jensen, Henrik; Tufto, Jarle; Sæther, Bernt-Erik; Ringsby, Thor Harald

    2013-09-01

    When investigating parasite-host dynamics in wild populations, a fundamental parameter to investigate is prevalence. This quantifies the percentage of individuals infected in the population. Investigating how prevalence changes over time and space can reveal interesting aspects in the parasite-host relationship in natural populations. We investigated the dynamic between a common avian parasite (Syngamus trachea) in a host metapopulation of house sparrows (Passer domesticus) on the coast of Helgeland in northern Norway. We found that parasite prevalence varied in both time and space. In addition, the parasite prevalence was found to be different between demographic groups in the local populations. Our results reveal just how complex the dynamic between a host and its parasite may become in a fragmented landscape. Although temperature may be an important factor, the specific mechanisms causing this complexity are not fully understood, but need to be further examined to understand how parasite-host interactions may affect the ecological and evolutionary dynamics and viability of host populations.

  1. Sustainable Marketing

    NARCIS (Netherlands)

    Dam, van Y.K.

    2017-01-01

    In this article, three different conceptions of sustainable marketing are discussed and compared. These different conceptions are referred to as social, green, and critical sustainable marketing. Social sustainable marketing follows the logic of demand-driven marketing management and places the

  2. Sustainability Frontiers

    Science.gov (United States)

    Selby, David

    2010-01-01

    This article introduces Sustainability Frontiers, a newly formed, international, not-for-profit alliance of sustainability and global educators dedicated to challenging and laying bare the assumptions, exposing the blind spots, and transgressing the boundaries of mainstream understandings of sustainability-related education. Among the orthodoxies…

  3. Sustainable Marketing

    NARCIS (Netherlands)

    Dam, van Y.K.

    2017-01-01

    In this article, three different conceptions of sustainable marketing are discussed and compared. These different conceptions are referred to as social, green, and critical sustainable marketing. Social sustainable marketing follows the logic of demand-driven marketing management and places the resp

  4. Optimization of removal and recycling ratio of cover crop biomass using carbon balance to sustain soil organic carbon stocks in a mono-rice paddy system

    NARCIS (Netherlands)

    Haque, Md. Mozammel; Kim, Sang Yun; Kim, Gil Won; Kim, Pil Joo

    2015-01-01

    The cultivation of a winter cover crop as green manure is strongly recommended to improve soil quality in mono-rice paddy systems; however, the biomass is largely removed to feed cattle in many Asian regions. To determine the minimum recycling ratio of the biomass that can sustain soil organic carbo

  5. Towards Intelligently - Sustainable Cities?

    Directory of Open Access Journals (Sweden)

    Luca Salvati

    2013-04-01

    Full Text Available In the quest for achieving sustainable cities, Intelligent and Knowledge City Programmes (ICPs and KCPs represent cost-efficient strategies for improving the overall performance of urban systems. However, even though nobody argues on the desirability of making cities “smarter”, the fundamental questions of how and to what extent can ICPs and KCPs contribute to the achievement of urban sustainability lack a precise answer. In the attempt of providing a structured answer to these interrogatives, this paper presents a methodology developed for investigating the modalities through which ICPs and KCPs contribute to the achievement or urban sustainability. Results suggest that ICPs and KCPs efficacy lies in supporting cities achieve a sustainable urban metabolism through optimization, innovation and behavior changes.

  6. The Density of Sustainable Settlements

    DEFF Research Database (Denmark)

    Lauring, Michael; Silva, Victor; Jensen, Ole B.

    2010-01-01

    This paper is the initial result of a cross-disciplinary attempt to encircle an answer to the question of optimal densities of sustainable settlements. Urban density is an important component in the framework of sustainable development and influences not only the character and design of cities...

  7. The Density of Sustainable Settlements

    DEFF Research Database (Denmark)

    Lauring, Michael; Silva, Victor; Jensen, Ole B.;

    2010-01-01

    This paper is the initial result of a cross-disciplinary attempt to encircle an answer to the question of optimal densities of sustainable settlements. Urban density is an important component in the framework of sustainable development and influences not only the character and design of cities...

  8. External costs in the global energy optimization models. A tool in favour of sustain ability; Los costes externos en los modelos energeticos globales de optimizacion. Una herramienta para la sostenibilidad

    Energy Technology Data Exchange (ETDEWEB)

    Cabal Cuesta, H.

    2007-07-01

    The aim of this work is the analysis of the effects of the GHG external costs internalization in the energy systems. This may provide a useful tool to support decision makers to help reaching the energy systems sustain ability. External costs internalization has been carried out using two methods. First, CO{sub 2} externalities of different power generation technologies have been internalized to evaluate their effects on the economic competitiveness of these present and future technologies. The other method consisted of analysing and optimizing the global energy system, from an economic and environmental point of view, using the global energy optimization model generator, TIMES, with a time horizon of 50 years. Finally, some scenarios regarding environmental and economic strategic measures have been analysed. (Author)

  9. Optimization of Prescription for Double-layered Erhuang Sustained-release Suppository by ;Multi-index Orthogonal Experiment%多指标正交试验优化儿黄缓释双层栓处方

    Institute of Scientific and Technical Information of China (English)

    郑竹; 姜继宗; 富波; 韩凤娟; 王艳宏

    2015-01-01

    目的:优化儿黄缓释双层栓的处方。方法选择聚乙二醇(PEG)400、PEG4000、羟丙基甲基纤维素(HPMC)的用量为影响因素,采用L9(34)正交试验,以3个不同时间点的累积释放度作为指标,进行综合评分,分别对儿黄缓释双层栓的内层和外层进行优化设计。结果优选出内层的最优处方为 HPMC∶PEG4000∶PEG400=1.5∶10∶4,外层的最优处方为 HPMC∶PEG4000∶PEG400=0.5∶10∶4。结论根据本试验优化处方制备的儿黄缓释双层栓成型性好,并具有良好的缓释作用,对中药栓剂的研究开发具有一定的参考价值。%Objective To optimize prescription for double-layered Erhuang sustained-release suppository. Methods Amounts of PEG400, PEG4000, HPMC were selected as influence factors for L9(34) orthogonal experiment. A comprehensive assessment was conducted by setting the cumulative release degree at three different time points as index, and the inner and outer layers of double-layered Erhuang sustained-release suppository were optimized. Results The best prescription was the inner HPMC∶PEG4000∶PEG400=1.5∶10∶4;outer HPMC∶PEG4000∶PEG400=0.5∶10∶4. Conclusion Prescription for double-layered Erhuang sustained-release suppository has good forming property and a good sustained-release effect according to the optimized prescription, which has certain reference value for researches and development of TCM suppository.

  10. Sustainable Disruptions

    DEFF Research Database (Denmark)

    Friis, Silje Alberthe Kamille; Kjær, Lykke Bloch

    2016-01-01

    Since 2012 the Sustainable Disruptions (SD) project at the Laboratory for Sustainability at Design School Kolding (DK) has developed and tested a set of design thinking tools, specifically targeting the barriers to economically, socially, and environmentally sustainable business development...... invested in the issue of sustainable business development, in particular the leaders and employees of SMEs, but also to design education seeking new ways to consciously handle and teach the complexity inherent in sustainable transformation. Findings indicate that the SD design thinking approach contributes....... The tools have been applied in practice in collaboration with 11 small and medium sized companies (SMEs). The study investigates these approaches to further understand how design thinking can contribute to sustainable transition in a business context. The study and the findings are relevant to organizations...

  11. The investigation of the impacts of walls and green facades on the optimization of energy consumption in buildings and its role in a sustainable development

    Directory of Open Access Journals (Sweden)

    Sara Heidarian

    2014-07-01

    Full Text Available In recent decades,artificial environments, compared to the natural spaces in urban areas, areexpanding day by day. Following the same trend in Iran, apartment living framewithout any natural space has changed. And it is while the need to nature isstill alive in human beings. Moreover, all over the world due to major problemssuch as global warming, air and water pollution, excessive energy consumptionand its high economic costs, utilizing technologies of sustainable architectureand specially creating green buildings has got great importance. In thisregard, the use of green areas can be used as appropriate strategy in order tosolve existing problems and creating sustainable architecture. In this paperwith research method based on library studies and descriptive analyticapproach, green walls, to improve the energy consumption efficiency inbuildings, have been investigated. And also the role of these systems in visualaesthetics of urban area in line with the objectives of sustainable developmentis examined. It seems that using green walls as a way to reduce the energyconsumption in buildings can be an effective option to advance the goals ofsustainablearchitecture.

  12. Metapopulation in bats of Southern Brazil Metapopulação em morcegos do sul do Brasil

    Directory of Open Access Journals (Sweden)

    NR Reis

    2012-08-01

    Full Text Available The purpose was to show that displacements, promoters of genetic diversity in metapopulations, increase the probability of survival of bat species adapted to medium and long-distance flights. Samples were taken in four forest fragments, distributed in three municipalities in northern Paraná, and the maximum distance between the studied areas is 20 km. A monthly sampling was performed for each fragment, for the period of July 2008 to June 2009. We used eight nets for collection which remained open during the first four hours of the night, totalling 192 hours during a year of study. The marking occurred from October 2008 to March 2009 and was accomplished through the use of anodised metal rings of four different colours. One hundred and fifty individuals were banded and since the first capture, four displacements were recorded. After five months of collecting and marking, one Carollia perspicillata was found three km away. Two Artibeus lituratus were recorded about 20 km from the marking place: the first one after 22 months and the second one after 24 months. Additionally, one Platyrrhinus lineatus was captured at about 20 km, after 26 months. As they moved around over considerable distances and are not monogamous, they mate with females of other fragments, exchanging genes and reducing or even avoiding inbreeding. Thus, populations of bats have the ability to increase genetic diversity in metapopulations, provided by displacements between the forest fragments. Species that behave like this are not vulnerable to isolation.Objetivou-se mostrar que os deslocamentos, promotores da diversidade genética em metapopulações, incrementam a probabilidade de sobrevivência das populações de espécies de morcegos adaptadas para voos de média e longa distância. As amostragens foram realizadas em quatro fragmentos florestais, distribuídos em três municípios da região norte do Paraná, sendo que a distância máxima entre as áreas de estudo foi de

  13. Stabilizing Sustainability

    OpenAIRE

    Andersen, Kirsti Reitan

    2017-01-01

    The publication of the Brundtland Report in 1987 put the topic of sustainable development on the political and corporate agenda. Defining sustainable development as “a development that meets the needs of the future without compromising the ability of future generations to meet their own needs” (WCED, 1987, p. 43), the Report also put a positive spin on the issue of sustainability by upholding capitalist beliefs in the possibility of infinite growth in a world of finite resource...

  14. Computational sustainability

    CERN Document Server

    Kersting, Kristian; Morik, Katharina

    2016-01-01

    The book at hand gives an overview of the state of the art research in Computational Sustainability as well as case studies of different application scenarios. This covers topics such as renewable energy supply, energy storage and e-mobility, efficiency in data centers and networks, sustainable food and water supply, sustainable health, industrial production and quality, etc. The book describes computational methods and possible application scenarios.

  15. Decomposed pairwise regression analysis of genetic and geographic distances reveals a metapopulation structure of stream-dwelling Dolly Varden charr.

    Science.gov (United States)

    Koizumi, Itsuro; Yamamoto, Shoichiro; Maekawa, Koji

    2006-10-01

    Isolation by distance is usually tested by the correlation of genetic and geographic distances separating all pairwise populations' combinations. However, this method can be significantly biased by only a few highly diverged populations and lose the information of individual population. To detect outlier populations and investigate the relative strengths of gene flow and genetic drift for each population, we propose a decomposed pairwise regression analysis. This analysis was applied to the well-described one-dimensional stepping-stone system of stream-dwelling Dolly Varden charr (Salvelinus malma). When genetic and geographic distances were plotted for all pairs of 17 tributary populations, the correlation was significant but weak (r(2) = 0.184). Seven outlier populations were determined based on the systematic bias of the regression residuals, followed by Akaike's information criteria. The best model, 10 populations included, showed a strong pattern of isolation by distance (r(2) = 0.758), suggesting equilibrium between gene flow and genetic drift in these populations. Each outlier population was also analysed by plotting pairwise genetic and geographic distances against the 10 nonoutlier populations, and categorized into one of the three patterns: strong genetic drift, genetic drift with a limited gene flow and a high level of gene flow. These classifications were generally consistent with a priori predictions for each population (physical barrier, population size, anthropogenic impacts). Combined the genetic analysis with field observations, Dolly Varden in this river appeared to form a mainland-island or source-sink metapopulation structure. The generality of the method will merit many types of spatial genetic analyses.

  16. Integrating Multi-Domain Distributed Energy Systems with Electric Vehicle PQ Flexibility: Optimal Design and Operation Scheduling for Sustainable Low-Voltage Distribution Grids

    DEFF Research Database (Denmark)

    Morvaj, Boran; Knezovic, Katarina; Evins, Ralph

    2016-01-01

    for minimising carbon emission in low-voltage distribution grids with high share of distributed energy resources and electric vehicles. The framework determines optimal EV flexibility usage (both active and reactive) while satisfying electric and thermal building demands, and maintaining the distribution grid...... in the stable operation. The model was applied to a real low-voltage Danish distribution grid where measurement data is available on hourly basis in order to determine EV flexibility impacts on carbon emissions, as well as the benefits of optimal DES design. The influence of EV reactive power control...

  17. Computational Sustainability

    OpenAIRE

    Eaton, Eric; University of Pennsylvania; Gomes, Carla P.; Cornell University; Williams, Brian; Massachusetts Institute of Technology

    2014-01-01

    Computational sustainability problems, which exist in dynamic environments with high amounts of uncertainty, provide a variety of unique challenges to artificial intelligence research and the opportunity for significant impact upon our collective future. This editorial provides an overview of artificial intelligence for computational sustainability, and introduces this special issue of AI Magazine.

  18. Sustaining dairy

    NARCIS (Netherlands)

    Villarreal Herrera, Georgina

    2017-01-01

    Dairy in Europe has undergone many changes in the last few years—the abolition of milk production quotas being a fundamental one. This study explores these changes in relation to the sustained social and environmental viability of the sector and how dairy processors' sustainability

  19. Sustainable leadership

    NARCIS (Netherlands)

    Tideman, S.G.; Arts, M.; Zandee, D.P.

    2013-01-01

    This paper offers a definition of the type of leadership that is necessary for creating sustainable organisations: sustainable leadership. After exploring shifts in economic and organisational theory caused by new insights from fields such as (social) neuroscience, and mega-trends in the macro-econo

  20. Stabilizing Sustainability

    DEFF Research Database (Denmark)

    Reitan Andersen, Kirsti

    The publication of the Brundtland Report in 1987 put the topic of sustainable development on the political and corporate agenda. Defining sustainable development as “a development that meets the needs of the future without compromising the ability of future generations to meet their own needs...

  1. Sustainable Learning

    Science.gov (United States)

    Cadwell, Louise; Dillon, Robert

    2011-01-01

    Green schools have moved into a new era that focuses on building a culture of sustainability in every aspect of learning in schools. In the early stages of sustainability education, the focus was on recycling and turning off the lights. Now, students and adults together are moving into the areas of advocacy and action that are based on a deep…

  2. Sustainability Labeling

    NARCIS (Netherlands)

    Dam, van Y.K.

    2017-01-01

    Sustainability labeling originated from a need to protect the identity of alternative systems of food production and to increase market transparency. From the 1980s onwards sustainability labeling has changed into a policy instrument replacing direct government regulation of the food market, and a

  3. Sustainable systems

    NARCIS (Netherlands)

    Sukkel, W.

    2009-01-01

    To put sustainable agriculture into practice, the organic food chain should be considered in its entirety. Such is the vision of the Dutch organic sector. By emphasizing this holistic view, organic farmers can make a significant contribution to increasing the sustainability of agriculture. Through s

  4. Sustainable Transition

    DEFF Research Database (Denmark)

    2014-01-01

    What. The chapter addresses designing for sustainability as interventions in socio-technical systems and social practices of users and communities. It calls for reflexive design practices challenging dominant regimes and shaping alternative design spaces. The specific case is the reconfiguration...... of agendas/vision, technologies, actors and institutions in the emergent design of an urban mobility system based on an electric car sharing system. Why. Designing for sustainability is a fundamental challenge for future design practices; designers have to obtain an ability to contribute to sustainable...... transition processes. Where. Addresses design processes aimed at sustainable transition enacted in complex social settings, socio-technical systems involving many different actors and agendas. How. The chapter outlines a conceptual and analytic framework for a reflexive design practice for sustainability...

  5. Sustainable Universities

    DEFF Research Database (Denmark)

    Grindsted, Thomas Skou

    2011-01-01

    , has put a counter pressure on the university, forcing it to review its role as a driver for sustainable development. Today, universities and intergovernmental institutions have developed more than 31 SHE declarations, and more than 1400 universities have signed a SHE declaration globally. However....... Declarations tend to have impact on three trends. Firstly, there is emerging international consensus on the university’s role and function in relation to sustainable development; secondly, the emergence of national legislation, and thirdly, an emerging international competition to be leader in sustainable......Declarations on Sustainability in Higher Education (SHE) can be viewed as a piece of international regulation. Over the past 30 years research at universities has produced convincing data to warn about deterioration of the environment, resource scarcity and the need for sustainability. This in turn...

  6. 响应面法优化富马酸喹硫平缓释片处方%Optimization of the Formulation of Fumarate Quetiapine Sustained-release Tablets by Response Surface Methodology

    Institute of Scientific and Technical Information of China (English)

    沈艳; 任丽莉; 王丞; 陈建龙; 陈国广

    2012-01-01

    OBJECTIVE:To optimize the formulation of Fumarate quetiapine sustained-release tablets. METHODS:Using comprehensive score of the cumulate release rate behavior as response value, response surface methodology of 3 factors and 3 levels was used to determine the viscosity and dosage of HPMC and the dose of natrium citricum and lactose, and to explore drug release mechanism in vitro. RESULTS: HPMC K15M was selected as framework material, and the dosage of it was 13.5% ; the doses of sodium citrate and lactose were 9.5% and 14%. Sustained-release tablets in vitro release fitted to the Higuchi equation, the release behavior in vitro is diffusion combined with corrosion. CONCLUSION: The optimized preparation process of Fumarate quetiapine sustained-release tablet is stable, feasible and the tablets have sustained-release behavior.%目的:优化富马酸喹硫平缓释片处方.方法:以累积释放度综合评分作为响应值,采用3因素3水平的响应面法,确定富马酸喹硫平缓释片处方中羟丙甲纤维素(HPMC)的黏度、用量与枸橼酸钠、乳糖的用量,并探讨其体外释药机制.结果:骨架材料选择HPMC K15M,考虑到实际操作便利确定其用量为13.5%,枸橼酸钠用量为9.5%,乳糖用量为14%.缓释片体外释放符合Higuchi方程,释药机制为扩散和溶蚀并存的双重机制.结论:筛选所得的富马酸喹硫平缓释片处方工艺稳定可行,有一定的缓释作用.

  7. Foods and dietary patterns that are healthy, low-cost, and environmentally sustainable: a case study of optimization modeling for New Zealand.

    Directory of Open Access Journals (Sweden)

    Nick Wilson

    Full Text Available OBJECTIVE: Global health challenges include non-communicable disease burdens, ensuring food security in the context of rising food prices, and environmental constraints around food production, e.g., greenhouse gas [GHG] emissions. We therefore aimed to consider optimized solutions to the mix of food items in daily diets for a developed country population: New Zealand (NZ. METHODS: We conducted scenario development and linear programming to model 16 diets (some with uncertainty. Data inputs included nutrients in foods, food prices, food wastage and food-specific GHG emissions. FINDINGS: This study identified daily dietary patterns that met key nutrient requirements for as little as a median of NZ$ 3.17 per day (US$ 2.41/d (95% simulation interval [SI] = NZ$ 2.86 to 3.50/d. Diets that included "more familiar meals" for New Zealanders, increased the cost. The optimized diets also had low GHG emission profiles compared with the estimate for the 'typical NZ diet' e.g., 1.62 kg CO2e/d for one scenario (95%SI = 1.39 to 1.85 kg CO2e compared with 10.1 kg CO2e/d, respectively. All of the optimized low-cost and low-GHG dietary patterns had likely health advantages over the current NZ dietary pattern, i.e., lower cardiovascular disease and cancer risk. CONCLUSIONS: We identified optimal foods and dietary patterns that would lower the risk of non-communicable diseases at low cost and with low greenhouse gas emission profiles. These results could help guide central and local government decisions around which foods to focus policies on. That is which foods are most suitable for: food taxes (additions and exemptions; healthy food vouchers and subsidies; and for increased use by public institutions involved in food preparation.

  8. Optimizing Sustainable Integrated Use of Groundwater, Surface Water and Reclaimed Water for the Competing Demands of Agricultural Net Return and Urban Population

    OpenAIRE

    Landa, Silvia Anastasia

    2016-01-01

    Rapid population growth increases the competing water demand for agriculture and municipalities. This situation urges the necessity of using integrated water management to increase water supply and find possible symbiotic urban-agriculture relationships. Many studies have been done to simulate the integrated use of surface water, groundwater and reclaimed water for different water users. However, few studies use simulation/optimization (S-O) models for water resources to explicitly represent ...

  9. Sustainable Consumption

    DEFF Research Database (Denmark)

    Røpke, Inge

    2015-01-01

    The intention of this chapter is to explore the role of consumption and consumers in relation to sustainability transition processes and wider systemic transformations. In contrast to the individualistic focus in much research on sustainable consumption, the embeddedness of consumption activities...... in wider social, economic and technological frameworks is emphasised. In particular, the chapter is inspired by practice theory and transition theory. First, various trends in consumption are outlined to highlight some of the challenges for sustainability transitions. Then, it is discussed how consumption...... patterns are shaped over time and what should be considered in sustainability strategies. While discussions on consumption often take their point of departure in the perspective of the individual and then zoom to the wider context, the present approach is the opposite. The outline starts with the basic...

  10. Sustainable responsibilities?

    DEFF Research Database (Denmark)

    Lystbæk, Christian Tang

    2015-01-01

    This working paper analyzes the conceptions of corporate responsibility for sustainable development in EU policies on CSR. The notion of corporate responsibility has until recently been limited to economical and legal responsibilities. Based on this narrow conception of corporate responsibility.......e. a combination of destruction and construction, this chapter will deconstruct conceptions of responsibility for sustainable development in these EU documents on CSR. A deconstructive conceptual analysis involves destructing dominant interpretations of a text and allowing for constructions of alternative...... such as sustainability actually means, but on what the concept says and does not say. A deconstructive analysis of EU policies on CSR, then, pinpoints that such policies are sites of conceptual struggles. This kind of analysis is suitable for studying conceptions of corporate responsibility for sustainable development...

  11. Sustainable Cities

    DEFF Research Database (Denmark)

    Georg, Susse; Garza de Linde, Gabriela Lucía

    Judging from the number of communities and cities striving or claiming to be sustainable and how often eco-development is invoked as the means for urban regeneration, it appears that sustainable and eco-development have become “the leading paradigm within urban development” (Whitehead 2003......), urban design competitions are understudied mechanisms for bringing about field level changes. Drawing on actor network theory, this paper examines how urban design competitions may bring about changes within the professional field through the use of intermediaries such as a sustainable planning....../assessment tool. The context for our study is urban regeneration in one Danish city, which had been suffering from industrial decline and which is currently investing in establishing a “sustainable city”. Based on this case study we explore how the insights and inspiration evoked in working with the tool...

  12. Sustainable Futures

    Science.gov (United States)

    Sustainable Futures is a voluntary program that encourages industry to use predictive models to screen new chemicals early in the development process and offers incentives to companies subject to TSCA section 5.

  13. Agriculture: Sustainability

    Science.gov (United States)

    Sustainability creates and maintains the conditions under which humans and nature can exist in productive harmony, that permit fulfilling the food, feed, and fiber needs of our country and the social, economic and other requirements.

  14. Sustainable Transportation

    DEFF Research Database (Denmark)

    Hall, Ralph P.; Gudmundsson, Henrik; Marsden, Greg

    2014-01-01

    The transportation system is the backbone of economic and social progress and the means by which humans access goods and services and connect with one another. Yet, as the scale of transportation activities has grown worldwide, so too have the negative environmental, social, and economic impacts...... that relate to the construction and maintenance of transportation infrastructure and the operation or use of the different transportation modes. The concept of sustainable transportation emerged in response to these concerns as part of the broader notion of sustainable development. Given the transportation...... sector’s significant contribution to global challenges such as climate change, it is often said that sustainable development cannot be achieved without sustainable transportation....

  15. Sustainable Threads

    National Research Council Canada - National Science Library

    Blaine Friedlander

    2016-01-01

    .... Lewis, who is also a faculty fellow at Cornell's Atkinson Center for a Sustainable Future, focuses her research on the impact of technology in the apparel industry, the behavior of fashion brands...

  16. Stabilizing Sustainability

    DEFF Research Database (Denmark)

    Reitan Andersen, Kirsti

    The publication of the Brundtland Report in 1987 put the topic of sustainable development on the political and corporate agenda. Defining sustainable development as “a development that meets the needs of the future without compromising the ability of future generations to meet their own needs......” (WCED, 1987, p. 43), the Report also put a positive spin on the issue of sustainability by upholding capitalist beliefs in the possibility of infinite growth in a world of finite resources. While growth has delivered benefits, however, it has done so unequally and unsustainably. This thesis focuses...... on the textile and fashion industry, one of the world’s most polluting industries and an industry to some degree notorious for leading the ‘race to the bottom’ in global labour standards. Despite being faced with increasing demands to practise sustainability, most textile and fashion companies continue to fail...

  17. Sustainable Transportation

    DEFF Research Database (Denmark)

    Hall, Ralph P.; Gudmundsson, Henrik; Marsden, Greg

    2014-01-01

    The transportation system is the backbone of economic and social progress and the means by which humans access goods and services and connect with one another. Yet, as the scale of transportation activities has grown worldwide, so too have the negative environmental, social, and economic impacts ...... sector’s significant contribution to global challenges such as climate change, it is often said that sustainable development cannot be achieved without sustainable transportation....

  18. SUSTAINABLE TRANSPORTATION

    Directory of Open Access Journals (Sweden)

    Linda STEG

    2007-01-01

    Full Text Available This paper discusses possible contributions of psychologists to sustainable transportation. It is argued that in order to reach sustainable transportation, among others, behaviour changes of individual car users are needed. As transport policies will be more effective if they target important antecedents of travel behaviour, first, factors influencing such behaviour are discussed. It is argued that car use is very attractive and sometimes even necessary for many different reasons. This implies that a combination of policies is called for, each targeting different factors that support car use and hinder the use of more sustainable modes of transport. Next, the paper elaborates on policy strategies that may be employed to achieve sustainable transportation by changing car use. Increasing the attractiveness of sustainable transport modes by means of pull measures seems not sufficient to reduce the level of car use. Besides, car use should be made less attractive by means of push measures to force drivers to reconsider their travel behaviour. The acceptability of such policies may be increased by clearly communicating the aim of these policies, and the expected positive consequences (e.g., less congestion, improved environmental quality. Moreover, possible negative effects for individual freedom may be compensated by implementing additional policies aimed at facilitating the use of sustainable transport modes.

  19. Sustainable markets for sustainable energy

    Energy Technology Data Exchange (ETDEWEB)

    Millan, J.; Smyser, C.

    1997-12-01

    The author discusses how the Inter-American Development Bank (IDB) is involved in sustainable energy development. It presently has 50 loans and grants for non conventional renewable energy projects and ten grants for efficiency programs for $600 and $17 million respectively, representing 100 MW of power. The IDB is concerned with how to create a sustainable market for sustainable energy projects. The IDB is trying to work with government, private sector, NGOs, trading allies, credit sources, and regulators to find proper roles for such projects. He discusses how the IDB is working to expand its vision and objectives in renewable energy projects in Central and South America.

  20. 生境破坏的空间结构对集合种群动态的影响%Effect of habitat destruction structure on the dynamics of metapopulation

    Institute of Scientific and Technical Information of China (English)

    张彦宇; 罗鑫娟

    2013-01-01

    To study the effects of habitat destruction on metapopulation dynamics, a model for metapopulation dynamics has been constructed, based on the cellular automaton model, which includes not only metapopulation information about spatial structure, but also the global density and local density of destruction habitat. With the model reveals the spatial structure of destructed habitat profoundly affects the dynamics of metapopulation. The mixed distribution of destructed habitat and suitable habitat, the global density of destructed habitat is bigger than the local, which makes the danger of metapopulation extinction. While with clustering distribution, the global density of destructed habitat is smaller than the local, which will promote the persistence of metapopulation increase. General, the global and local density of metapopulation are in direct proportion to the global density of destructed habitat, and in inverse proportion to the local density of destructed habitat. But, with certain global density of destructed habitat, the global and local density of metapopulation decrease with the increase of the local density of destructed habitat. There is a threshold, which the local density of metapopulationis below, the metapopulation would extinct. All these results show that it is important to construct the connectivity among patches and the local density of metapopulation, although habitat restoration and habitat quality improvement are necessary.%构建任意生境破坏结构下集合种群动态的元胞自动机模型,研究生境破坏的空间结构对集合种群全局密度及局部密度的影响.该模型不仅包括了生境破坏的空间结构,而且能够描述集合种群的空间分布模式.模型结果表明:生境破坏的空间结构复杂地影响着集合种群的全局密度和局部密度;生境破坏的混合分布增大了集合种群灭绝的风险;生境破坏的聚集分布降低了集合种群灭绝的风险.在生境破坏比例较

  1. Specificities of sustainable tourism planning

    Directory of Open Access Journals (Sweden)

    Jegdić Vaso

    2013-01-01

    Full Text Available In the past two decades, companies have been mentioning achievement of sustainability in their activities as a target of companies, governments and non-profit organizations, although measuring the degree to which an organization conducts its activities in a sustainable manner, can be very difficult. Sustainable tourism development requires a process of planning and management that will unite the interests of various stakeholders in a sustainable and strategic way. It requires an understanding of the meaning of sustainable development and guiding values for promoting sustainable tourism. The paper points to the importance of cross-sector partnerships and the roles of different stakeholders in the planning of sustainable tourism projects. Special importance is given to the community of which a willingness to understand the impacts of tourism industry is expected, as well as various procedures of engagement in participatory planning, consensus building and conflict resolution among all stakeholders. The aim of this research is to find an optimal model of planning of sustainable tourism projects that would take into consideration the interests of all stakeholders and reflect the specificities imposed by the acceptance of the concept of sustainable development by all participants in the project.

  2. Quantification and valuation of ecosystem services to optimize sustainable re-use for low-productive drained peatlands (LIFEPeatLandUse)

    Science.gov (United States)

    Tolvanen, Anne; Parviainen, Miia; Ojanen, Paavo

    2016-04-01

    More than half of the original peatlands have been drained in Finland to increase tree growth. However, 20% of the drained peatland area is low-productive, and does not produce enough timber to fulfill commercial purposes. At the same time, their biodiversity is degraded, they may continue environmental loading to watercourses, and act as greenhouse gas (GHG) sources. A key question concerning the use of peatlands in Finland is what to do with these low-productive drained peatlands that have been left aside from active forestry. These low-productive drained peatlands can be re-used in many different ways. The problem is that the impacts of different re-use options on biodiversity, environment and economy are not yet fully understood and thus it is hard to give proposals for re-use actions. The challenge is to develop mechanisms that can balance the conflicting demands on the use of peatlands and to ensure their sustainable use. Our 5-year EU funded LIFE+ project LIFEPeatLandUse (2013-2018, LIFE12/ENV/FI/150) consolidates the knowledge on the impacts of peatland re-use on ecosystem services. Under investigation, there are seven different peatland re-use options, representing the economic activity as well as measures related to the protection. The purpose is to evaluate and predict their potential impacts on the peatland landscapes, if they were applied in practice. The aim is to find cost-efficient re-use options to low-productive drained peatlands, which help to prevent or stop decline of biodiversity and environmental loading to watercourses, and improve capacity of peatlands to store greenhouse gases.

  3. OPTIMALISASI LAHAN USAHATANI BERBASIS KAKAO UNTUK PEMBANGUNAN PERTANIAN BERKELANJUTAN DI DAS KRUENG SEULIMUM PROVINSI ACEH (Land Optimization of Cocoa Based on Farming for Agricultural Sustainable Development in Krueng Seulimum Watershed Aceh Province

    Directory of Open Access Journals (Sweden)

    Halim Akbar

    2015-11-01

    Full Text Available ABSTRAK Perubahan penggunaan lahan di DAS Krueng Seulimum menjadi lahan pertanian tanpa penerapan agroteknologi telah menyebabkan tingginya erosi dan produktivitas lahan yang rendah. Penelitian ini bertujuan untuk mengkaji karakteristik lahan dan agroteknologi yang diterapkan pada tanaman kakao, menganalisis alokasi lahan optimal untuk usahatani berbasis kakao dan agroteknologi yang cocok untuk mengurangi erosi dan meningkatkan pendapatan petani, dan merumuskan perencanaan usahatani berbasis kakao berkelanjutan. Hasil penelitian menunjukkan bahwa usahatani berbasis kakao berkelanjutan dapat dicapai dengan penerapan agroteknologi pemupukan lengkap pada lereng 7%, pemupukan lengkap+pembuatan teras gulud dengan tanaman penguat teras pada lereng 14% dan pemupukan lengkap+pembuatan teras gulud dengan tanaman penguat teras + pemberian mulsa 6 ton.ha-1.thn-1 pada lereng 21% dapat mengendalikan erosi hingga lebih kecil dari erosi yang dapat ditoleransikan (ETol dan memberikan pendapatan usahatani lebih besar dari kebutuhan untuk hidup layak (KHL. Tipe usahatani yang optimal di DAS Krueng Seulimum adalah tipe usahatani kakao+pisang (KPs pada lahan 1,50 ha dengan menerapkan agroteknologi pemupukan+pembuatan teras gulud+tanaman penguat teras ditambah dengan pemberian mulsa 6 ton.ha-1.thn-1 dapat menekan erosi di bawah ETol (16,03-38,64 ton.ha-1.thn-1 dengan pendapatan optimum sebesar Rp 42,954,150 kk.thn-1.   ABSTRACT Land use changes in the Krueng Seulimum watershed into agricultural land without application of suitable agro-technology have led to high erosion and low land productivity. This study aims to assess the characteristics of the land and agro-technology applied the cocoa crop, analyze the allocation of optimal land for cocoa farming and suitable agro-technology to reduce erosion and to increase farmers’ income and formulate cocoa based on sustainable farming plans. The results show that sustainable cocoa based farming can be achieved with the

  4. Optimizing the preparation of doxycycline hydrochloride sustained release tablet using response surface methodology%响应面法优化盐酸多西环素缓释片处方工艺

    Institute of Scientific and Technical Information of China (English)

    喻佰启; 王永禄; 殷海翔; 王栋; 吕贝贝; 李学明

    2014-01-01

    目的:利用响应面分析法优化盐酸多西环素缓释片处方。方法通过单因素考察确定对释放度影响最大的3个因素:羟丙基甲基纤维素(hydroxypropyl methyl cellulose,HPMC)的用量、粘合剂聚乙烯吡咯烷酮-K30(polyvinylpyrrolidone-K30,PVP-K30)的浓度、乳糖与微晶纤维素(microcrystalline cellulose,MCC)的比例,以2 h、4 h、8 h 的释放度综合评分作为响应值,利用 Box-Benhnken中心组合实验设计原理,采用三因素三水平的响应面分析法,确定各处方的用量。结果筛选得到优化的处方为:HPMC K15质量分数为片重的30%、粘合剂PVP-K30浓度为10%、乳糖与MCC比例为13,其体外释药行为较理想。结论筛选所得的盐酸多西环素缓释片处方工艺稳定可行。%Objective In this article Response Surface Analysis(RSA)was applied to optimize the formulation of doxycycline hydrochloride sustained release tablet.Methods Single factor exploration was used to determine the three factors which have the greatest impact on the release rate.The three factors were the dosage of the HPMC in the total weight of the tablet,the concentration of PVP-K30,and the ratio of lactose to microcrystalline cellulose,respectively.The composite score of the release behaviour was taken as the response value.The dosage of the ingredients were determined by Box-Benhnke design principles and 3 factors and 3 levels.Results The optimized formulation and process are as follows:the dosage of the HPMC in the total weight of the tablet was 30%;the concentration of PVP-K30 was 10%,and the ratio of lactose to microcrystalline cellulose was 13.The release behavior in vitro is ideal.Conclusion The optimized preparation process of doxycycline hydrochloride sustained release tablet is stable,highly efficient and suitable for industrial production.

  5. Roundtabling Sustainability

    DEFF Research Database (Denmark)

    Ponte, Stefano

    2014-01-01

    The willingness of public authority to delegate social and environmental regulation to the private sector has varied from sector to sector, but has often led to the establishment of ‘voluntary’ standards and certifications on sustainability. Many of these have taken the form of ‘stewardship...... and procedures to meet ‘good practice’ in standard setting and management. This is opening space for competing initiatives that are less democratic, quicker, and more aligned with industry interests to establish substantial presence in the market for sustainability certifications. These tend to more easily...... councils’ and ‘sustainability roundtables’ and have been designed around a set of institutional features seeking to establish legitimacy, fend off possible criticism, and ‘sell’ certifications to potential users. The concept of ‘roundtabling’ emphasizes the fitting a variety of commodity...

  6. Roundtabling Sustainability

    DEFF Research Database (Denmark)

    Ponte, Stefano

    2014-01-01

    The willingness of public authority to delegate social and environmental regulation to the private sector has varied from sector to sector, but has often led to the establishment of ‘voluntary’ standards and certifications on sustainability. Many of these have taken the form of ‘stewardship...... councils’ and ‘sustainability roundtables’ and have been designed around a set of institutional features seeking to establish legitimacy, fend off possible criticism, and ‘sell’ certifications to potential users. The concept of ‘roundtabling’ emphasizes the fitting a variety of commodity......-specific sustainability situations into a form that not only ‘hears more voices’ (as in ‘multi-stakeholder’), but also portrays to give them equal standing at the table of negotiations (roundtable), thus raising higher expectations on accountability, transparency and inclusiveness. In this article, I examine to what...

  7. Sustainability Evaluation.

    Science.gov (United States)

    Stichnothe, Heinz

    2017-03-17

    The long-term substitution of fossil resources can only be achieved through a bio-based economy, with biorefineries and bio-based products playing a major role. However, it is important to assess the implications of the transition to a bio-based economy. Life cycle-based sustainability assessment is probably the most suitable approach to quantify impacts and to identify trade-offs at multiple levels. The extended utilisation of biomass can cause land use change and affect food security of the most vulnerable people throughout the world. Although this is mainly a political issue and governments should be responsible, the responsibility is shifted to companies producing biofuels and other bio-based products. Organic wastes and lignocellulosic biomass are considered to be the preferred feedstock for the production of bio-based products. However, it is unlikely that a bio-based economy can rely only on organic wastes and lignocellulosic biomass.It is crucial to identify potential problems related to socio-economic and environmental issues. Currently there are many approaches to the sustainability of bio-based products, both quantitative and qualitative. However, results of different calculation methods are not necessarily comparable and can cause confusion among decision-makers, stakeholders and the public.Hence, a harmonised, globally agreed approach would be the best solution to secure sustainable biomass/biofuels/bio-based chemicals production and trade, and to avoid indirect effects (e.g. indirect land use change). However, there is still a long way to go.Generally, the selection of suitable indicators that serve the purpose of sustainability assessment is very context-specific. Therefore, it is recommended to use a flexible and modular approach that can be adapted to various purposes. A conceptual model for the selection of sustainability indicators is provided that facilitates identifying suitable sustainability indicators based on relevance and significance in a

  8. Geosciences for sustainability

    Science.gov (United States)

    Ferreira, A. J. D.

    2012-04-01

    The world is facing overwhelming challenges with implications on the socio-economic performance and the quality of life around the planet. New solutions are needed to prevent, overcome or mitigate the turmoil processes caused by global change, resources exhaustion, and the procession of induced socio-economic impacts. To this end, solutions to optimize natural resources management, find new ways of using geophysical processes and properties as resources, and to use geosciences knowledge to find new, more sustainable ways to use earth resources, has to be sought for. This work is based on a literature review and on the building of a sustainable development strategy currently being prepared at the Portuguese Centro Region by the author, as part of a Research Centre strategy towards the improvement of environmental performance, of organizations, products and infrastructures. The strategy is based on the optimal use of environmental services, to which the role of geosciences and is a key element. Harnessing the abiotic milieu and processes and mimicking the multiple scale interactions of ecosystem to improve the organization and the productivity and value of man ventures. Geosciences provide the matrix where activities occur; therefore, their judicious management will optimise resources use, providing the best solutions. In addition, geosciences and their relation with ecosystem research can be managed to improve yields, by optimizing the agriculture and forestry practices. One way to proceed, that is in the forefront of research towards sustainability is by developing ways to include geosciences and ecosystems factors in novel Environmental Management tools such as Life Cycle Assessments or Environmental Management Systems. Furthermore, the knowledge on geosciences cycles and processes is of paramount importance in any planning process and in the design of infrastructures, which has a key direct or indirect role in the optimization of energy management.

  9. Sustainable finance

    NARCIS (Netherlands)

    dr. Margreet F. Boersma-de Jong

    2012-01-01

    Presentation for Springschool of Strategy, University of Groningen, 10 October 2012. The role of CSR is to stimulate ethical behaviour, and as a result, mutual trust in society. Advantage of CSR for the company and the evolution of CSR. From CSR to Sustainable Finance: how does CSR influence

  10. Sustainable Soesterkwartier

    NARCIS (Netherlands)

    Abrahams, H.; Goosen, H.; Jong, de F.; Sickmann, J.; Prins, D.

    2010-01-01

    The municipality of Amersfoort wants to construct an endurable and sustainable eco-town in the Soesterkwartier neighbourhood, by taking future climate change into account. The impact of climate change at the location of the proposed eco-town was studied by a literature review.

  11. Sustainable machining

    CERN Document Server

    2017-01-01

    This book provides an overview on current sustainable machining. Its chapters cover the concept in economic, social and environmental dimensions. It provides the reader with proper ways to handle several pollutants produced during the machining process. The book is useful on both undergraduate and postgraduate levels and it is of interest to all those working with manufacturing and machining technology.

  12. Sustainable Cities

    DEFF Research Database (Denmark)

    Georg, Susse; Garza de Linde, Gabriela Lucía

    /assessment tool. The context for our study is urban regeneration in one Danish city, which had been suffering from industrial decline and which is currently investing in establishing a “sustainable city”. Based on this case study we explore how the insights and inspiration evoked in working with the tool...

  13. Sustainable processing

    DEFF Research Database (Denmark)

    Kristensen, Niels Heine

    2004-01-01

    Kristensen_NH and_Beck A: Sustainable processing. In Otto Schmid, Alexander Beck and Ursula Kretzschmar (Editors) (2004): Underlying Principles in Organic and "Low-Input Food" Processing - Literature Survey. Research Institute of Organic Agriculture FiBL, CH-5070 Frick, Switzerland. ISBN 3-906081-58-3...

  14. Architecture Sustainability

    NARCIS (Netherlands)

    Avgeriou, Paris; Stal, Michael; Hilliard, Rich

    2013-01-01

    Software architecture is the foundation of software system development, encompassing a system's architects' and stakeholders' strategic decisions. A special issue of IEEE Software is intended to raise awareness of architecture sustainability issues and increase interest and work in the area. The fir

  15. Sustainable finance

    NARCIS (Netherlands)

    Boersma-de Jong, Margreet F.

    2012-01-01

    Presentation for Springschool of Strategy, University of Groningen, 10 October 2012. The role of CSR is to stimulate ethical behaviour, and as a result, mutual trust in society. Advantage of CSR for the company and the evolution of CSR. From CSR to Sustainable Finance: how does CSR influence Sustai

  16. Sustainable Buildings

    DEFF Research Database (Denmark)

    Tommerup, Henrik M.; Elle, Morten

    The scientific community agrees that: all countries must drastically and rapidly reduce their CO2 emissions and that energy efficient houses play a decisive role in this. The general attitude at the workshop on Sustainable Buildings was that we face large and serious climate change problems...

  17. Sustainable Happiness

    DEFF Research Database (Denmark)

    Landes, Xavier; Unger, Cindie; Andsbjerg, Kjartan;

    The world Happiness report 2012, commissioned by the united nations, noted that the tools of happiness research have the potential to recast the debate between economic growth and environmental protection. Moreover, it calls for an exploration of the established links between happiness and enviro...... and environmental sustainability. this report is an attempt to answer that call....

  18. Coevolutionary fine-tuning: evidence for genetic tracking between a specialist wasp parasitoid and its aphid host in a dual metapopulation interaction.

    Science.gov (United States)

    Nyabuga, F N; Loxdale, H D; Heckel, D G; Weisser, W W

    2012-04-01

    In the interaction between two ecologically-associated species, the population structure of one species may affect the population structure of the other. Here, we examine the population structures of the aphid Metopeurum fuscoviride, a specialist on tansy Tanacetum vulgare, and its specialist primary hymenopterous parasitoid Lysiphlebus hirticornis, both of which are characterized by multivoltine life histories and a classic metapopulation structure. Samples of the aphid host and the parasitoid were collected from eight sites in and around Jena, Germany, where both insect species co-occur, and then were genotyped using suites of polymorphic microsatellite markers. The host aphid was greatly differentiated in terms of its spatial population genetic patterning, while the parasitoid was, in comparison, only moderately differentiated. There was a positive Mantel test correlation between pairwise shared allele distance (DAS) of the host and parasitoid, i.e. if host subpopulation samples were more similar between two particular sites, so were the parasitoid subpopulation samples. We argue that while the differences in the levels of genetic differentiation are due to the differences in the biology of the species, the correlations between host and parasitoid are indicative of dependence of the parasitoid population structure on that of its aphid host. The parasitoid is genetically tracking behind the aphid host, as can be expected in a classic metapopulation structure where host persistence depends on a delay between host and parasitoid colonization of the patch. The results may also have relevance to the Red Queen hypothesis, whereupon in the 'arms race' between parasitoid and its host, the latter 'attempts' to evolve away from the former.

  19. 电力系统恢复过程中的工频过电压动态优化控制%Dynamic Optimal Control of Sustained Overvoltage During Power System Restoration

    Institute of Scientific and Technical Information of China (English)

    陈彬; 王洪涛

    2015-01-01

    A rational sustained overvoltage control strategy is an important part of the power system restoration plan.In order to overcome the limitations of the sustained overvoltage static control strategy,a dynamic multi-objective sustained overvoltage control model is proposed. With the restoration sequence as the optimization period, and restoration operation as the segmentation flag,the model proposed takes the whole process into consideration.According to the demand for restoration, the objective functions adapted to restoration are defined and the risk of restoration sequence,operation time of voltage control scheme and voltage deviation of energized buses are considered.An improved strength Pareto evolutionary algorithm(SPEA2) is used to get the Pareto frontier,and the lexicographic ordering method is used to get the optimal solution.The effectiveness of the proposed model is verified by comparing and analyzing the simulation results of dynamic and static optimization in different restoration scenarios in Shandong power grid.%合理的持续工频过电压控制策略是电力系统恢复方案的重要组成部分。针对当前持续工频过电压控制静态优化方法的局限性,以恢复序列为优化周期,以线路投运为分段标志,建立了电力系统恢复过程中的动态多目标工频过电压优化控制模型,实现一个恢复周期内的全过程优化。根据恢复过程需要,结合系统恢复方案,定义了恢复过程中的工频过电压优化控制的目标函数,综合考虑恢复序列的操作风险、电压控制方案的操作时间以及系统的电压偏差对电压控制方案的影响。利用改进的强度 Pareto 进化算法(SPEA2)求解模型的 Pareto 最优解,并采用字典序法选择出适应不同恢复场景的最优方案。以山东电网为例,分析和比较了不同恢复场景下动态优化和静态优化的仿真结果,表明所述模型能够适应电力系统恢复的要求。

  20. Study on the Formulation Optimization and Preparation Technology of Pioglitazone Hydrocloride Sustained-release Tablets%盐酸吡格列酮缓释片处方筛选及工艺研究

    Institute of Scientific and Technical Information of China (English)

    陈吉生; 陈燕忠; 庄文斌; 黎行山

    2012-01-01

    OBJECTIVE: To screen the formulation of Pioglitazone hydrocloride sustained-release tablets, and to optimize the preparation technology of it. METHODS: The type, amount and preparation technology of matrix material, bulking agent, and adhesive were investigated by determining accumulative rate of pioglitazone at different time in PBS to determine the formulation and preparation technology of tablet core. RESULTS: The tablet core was prepared with HPMC(K15M) as matrix material, microcrys-taline celulose as the bulking agent and 70% ethanol solution of 2% HPMC(E5) as adhesive material for Pioglitazone hydrocloride sustained-release tablets. The tablet was prepared by film coating method using 70% ethanol solution of Opadry as film coating material. Accumulative drug release rate of prepared 3 batches of samples were all more than 90% in 12 h. CONCLUSION: The preparation method is simple and the tablet is up to the requirements of sustained-release preparation.%目的:对盐酸吡格列酮缓释片进行处方筛选及工艺研究.方法:通过测定不同时间吡格列酮在pH6.8磷酸盐缓冲液中的累积释药率,对缓释骨架材料、填充剂、黏合剂的种类或规格、用量及工艺等进行考察,确立片芯处方及制备工艺.结果:片芯处方以羟丙基甲基纤维素(HPMC) (K15M)为骨架材料,微晶纤维素为填充剂,2%HPMC(E5)的70%乙醇溶液为黏合剂;制备工艺采用薄膜包衣法,以欧巴代的70%乙醇溶液作为薄膜包衣材料;所制3批样品12h的累积释药率均在90%以上.结论:本制剂工艺简单,符合缓释制剂要求.

  1. Treatment of digestate from a co-digestion biogas plant by means of vacuum evaporation: tests for process optimization and environmental sustainability.

    Science.gov (United States)

    Chiumenti, A; da Borso, F; Chiumenti, R; Teri, F; Segantin, P

    2013-06-01

    Vacuum evaporation consists in the boiling of a liquid substrate at negative pressure, at a temperature lower than typical boiling temperature at atmospheric conditions. Condensed vapor represents the so called condensate, while the remaining substrate represents the concentrate. This technology is derived from other sectors and is mainly dedicated to the recovery of chemicals from industrial by-products, while it has not been widely implemented yet in the field of agricultural digestate treatment. The present paper relates on experimental tests performed in pilot-scale vacuum evaporation plants (0.100 and 0.025 m(3)), treating filtered digestate (liquid fraction of digestate filtered by a screw-press separator). Digestate was produced by a 1 MWe anaerobic digestion plant fed with swine manure, corn silage and other biomasses. Different system and process configurations were tested (single-stage and two-stage, with and without acidification) with the main objectives of assessing the technical feasibility and of optimizing process parameters for an eventual technology transfer to full scale systems. The inputs and outputs of the process were subject to characterization and mass and nutrients balances were determined. The vacuum evaporation process determined a relevant mass reduction of digestate. The single stage configuration determined the production of a concentrate, still in liquid phase, with a total solid (TS) mean concentration of 15.0%, representing, in terms of mass, 20.2% of the input; the remaining 79.8% was represented by condensate. The introduction of the second stage allowed to obtain a solid concentrate, characterized by a content of TS of 59.0% and representing 5.6% of initial mass. Nitrogen balance was influenced by digestate pH: in order to limit the stripping of ammonia and its transfer to condensate it was necessary to reduce the pH. At pH 5, 97.5% of total nitrogen remained in the concentrate. This product was characterized by very high

  2. Sustainable Buildings

    DEFF Research Database (Denmark)

    Tommerup, Henrik M.; Elle, Morten

    The scientific community agrees that: all countries must drastically and rapidly reduce their CO2 emissions and that energy efficient houses play a decisive role in this. The general attitude at the workshop on Sustainable Buildings was that we face large and serious climate change problems...... that need urgent action. The built environment is an obvious area to put effort into because of the large and cost-effective energy saving potential and potential for Renewable Energy-based supply systems for buildings....

  3. The Dilemma, Evolution and Optimization Strategies of Stadiums Ecological Management of Sustainable Development%可持续发展中体育场馆生态管理的困境、演进与优化策略

    Institute of Scientific and Technical Information of China (English)

    李峰; 吕永安; 陈梅

    2015-01-01

    With the development of Nationalwide Fitness Programs, the strengthen of fitness awareness and increase of stadiums number, the practical difficulties and constraints in the operation and management of all types stadiums are increasingly trend, how to use the ecological view to solve the stadiums management problems about open to the public, optimizing the services properties and functions targeting of stadiums. the important thing is scientific, ecological management when the stadiums open to the public. This article will analyze the plight of ecological management, evolution and optimization strategies in the sustainable development of stadiums.%随着全民健身运动的广泛开展,人们健康意识的增强和体育场馆建设数量的增加,各类场馆在运行管理过程中遇到的现实困境和制约因素也日渐展现,如何利用生态学的观点解决场馆社会开放的管理问题、优化体育场馆的产品服务属性和功能目标定位,在体育场馆向社会开放的同时进行科学的、生态化的管理,是当前亟待解决的问题。将针对可持续发展中体育场馆生态管理的困境、演进与优化策略进行分析。

  4. Sustainable consumption and marketing

    NARCIS (Netherlands)

    Dam, van Y.K.

    2016-01-01

    Sustainable development in global food markets is hindered by the discrepancy between positive consumer attitudes towards sustainable development or sustainability and the lack of corresponding sustainable consumption by a majority of consumers. Apparently for many (light user) consumers the ‘

  5. Sustainable consumption and marketing

    NARCIS (Netherlands)

    Dam, van Y.K.

    2016-01-01

    Sustainable development in global food markets is hindered by the discrepancy between positive consumer attitudes towards sustainable development or sustainability and the lack of corresponding sustainable consumption by a majority of consumers. Apparently for many (light user) consumers the

  6. Building sustainability

    CSIR Research Space (South Africa)

    Mass Media

    2007-11-01

    Full Text Available establishment of its platform. Van Wyk believes that South Africa faces other challenges when it comes to sustainable building. “You can’t separate the process from the product,” he says. “South Africa still has to learn a lot and has to make many... stakeholders and implemented at an early stage. By G uy O lde nk ott e Bu idl ing Af ric aa rc hiv es Bu idl ing Af ric aa rc hiv es Perfect blend November 2007 jFM BUSINESS, RETAIL & LEISURE FACILITIES6 During the FM Expo...

  7. Optimization and pharmacokinetics of the sustained release microspheres of aripiprazole%阿立哌唑缓释微球的工艺优化及体内药动学研究

    Institute of Scientific and Technical Information of China (English)

    杨蕾; 彭博; 王明新; 刘津爱; 王毅飞; 王东凯

    2012-01-01

    目的:制备阿立哌唑缓释微球,使用星点设计-效应面法优化工艺,并对其体内血药浓度进行分析.方法:采用乳化溶剂挥发法制备阿立哌唑微球;以油相二氯甲烷体积、水相聚乙烯醇质量分数及乳化转速为自变量,以微球的平均粒径、跨距、载药量、包封率、产率及突释量为因变量,对制备工艺进行优化,并对优化后的工艺进行验证.采用HPLC法测定家兔血浆中药物浓度.结果:最佳工艺为二氯甲烷体积1.62mL,聚乙烯醇质量分数1.91%,乳化转速2161 r·min-1;按优化工艺制备的微球外观圆整、流动性好;平均粒径为41.54μm,跨距为1.01,载药量为18.82%,包封率为75.39%,产率为85.17%,突释为1.68%.自制徽球制剂在家兔体内d1有少量的突释,d5 ~d20维持较稳定的血药浓度,缓慢释放,之后浓度开始下降.结论:所优化的制备工艺重现性好,简单易行;星点设计-效应面法优化微球制备工艺预测性良好,所制备的微球具有较好的体外缓释特性;阿立哌唑缓释微球在家兔体内缓慢释放,该释药行为达到了预期的目的.%Objective: To prepare the sustained release microspheres of aripiprazole, to optimize the formulation by central composite design-response surface methodology, and to evaluate the pharmacokinetics of aripiprazole in rabbits. Methods: Emulsification-solvent evaporation method was used to prepare aripiprazole micro-spheres. The volume of CH2CI2 .polyvinyl alcohol (PVA) concentration and speed of mechanical stirring were listed as three independent variables; the dependent variables were mean diameter, span, durg content, encapsulation efficiency, yield and initial release. The central composite design-response surface methodology was constructed to optimize the formulations, and the optimized formulation was validated. HPLC method was used for the determination of aripiprazole in rabbit plasma. Results: The optimized preparation

  8. Grounded action: achieving optimal and sustainable change

    OpenAIRE

    Odis E. Simmons, Ph.D.; Toni A. Gregory, Ed. D.

    2005-01-01

    Grounded Action ist eine Anwendung und Erweiterung der Grounded Theory mit dem Ziel, Interventionen, Programme, Handlungsmodelle etc. zu entwerfen und zu implementieren. Der Grounded Action-Ansatz wurde konzipiert, um der Komplexität und Multidimensionalität von organisatorischen und sozialen Problemstellungen angemessen begegnen zu können. Die Grounded Theory als Strategie der datengegründeten Theorieentwicklung wird insoweit ausgeweitet, als es im Rahmen von Grounded Action um das Entwickel...

  9. Grounded action: Achieving optimal and sustainable change

    Directory of Open Access Journals (Sweden)

    Odis E. Simmons, Ph.D.

    2004-11-01

    Full Text Available Grounded action is the application and extension of grounded theory for the purpose of designing and implementing practical actions such as interventions, program designs, action models, social and organizational policies, and change initiatives. Grounded action is grounded theory with an added action component in which actions are systematically derived from a systematically derived explanatory grounded theory. Actions are grounded in the grounded theory in the same way that grounded theories are grounded in data. Grounded actionwas designed by the authors to address complex, multi-dimensionalorganizational and social problems and issues.

  10. Maintenance in sustainable manufacturing

    Directory of Open Access Journals (Sweden)

    Vladimir Stuchly

    2014-09-01

    Full Text Available Background: Sustainable development is about reaching a balance between economic, social, and environmental goals, as well as people's participation in the planning process in order to gain their input and support. For a company, sustainable development means adoption of such business strategy and actions that contribute to satisfying present needs of company and stakeholders, as well as simultaneous protection, maintenance and strengthening of human and environmental potential which will be needed in the future. This new approach forces manufacturing companies to change their previous management paradigms. New management paradigm should include new issues and develop innovative methods, practices and technologies striving for solving problem of shortages of resources, softening environment overload and enabling development of environment-friendly lifecycle of products. Hence, its realization requires updating existing production models as they are based on previously accepted paradigm of unlimited resources and unlimited regeneration capabilities. Maintenance plays a crucial role because of its impact on availability, reliability, quality and life cycle cost, thus it should be one of the main pillars of new business running model.  Material and methods: The following paper is a result of research on the literature and observation of practices undertaken by a company within maintenance area. Results and conclusions: The main message is that considering sustainable manufacturing requires considerable expanding range of analysis and focusing on supporting processes. Maintenance offers numerous opportunities of decreasing influence of business processes on natural environment and more efficient resources utilization. The goal of maintenance processes realizing sustainable development strategy is increased profitability of exploitation and optimization of total lifecycle cost without disturbing safety and environmental issues. 

  11. Sustainability; Sustentabilidade

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-10-15

    This chapter analyses the production chain of ethanol, considering the impacts on the quality of the air, water supplies, soil occupation and biodiversity, and the efforts for the soil preservation. It is pointed out the activities of the production cycle and use of bio ethanol due to great uncertainties as far the environmental impacts is concerning and that will deserve more attention in future evaluations. At same time, the chapter highlights another activities where the present acknowledge is sufficient to assure the control and/or prediction of consequences of the desired intervention on the environment media to accommodate the sugar and ethanol production expansion. The consideration is not conservative but to promote the sustainable development.

  12. Virtual Sustainability

    Directory of Open Access Journals (Sweden)

    William Sims Bainbridge

    2010-09-01

    Full Text Available In four ways, massively multiplayer online role-playing games may serve as tools for advancing sustainability goals, and as laboratories for developing alternatives to current social arrangements that have implications for the natural environment. First, by moving conspicuous consumption and other usually costly status competitions into virtual environments, these virtual worlds might reduce the need for physical resources. Second, they provide training that could prepare individuals to be teleworkers, and develop or demonstrate methods for using information technology to replace much transportation technology, notably in commuting. Third, virtual worlds and online games build international cooperation, even blending national cultures, thereby inching us toward not only the world consciousness needed for international agreements about the environment, but also toward non-spatial government that cuts across archaic nationalisms. Finally, realizing the potential social benefits of this new technology may urge us to reconsider a number of traditional societal institutions.

  13. Sustainability Science Needs Sustainable Data!

    Science.gov (United States)

    Downs, R. R.; Chen, R. S.

    2013-12-01

    Sustainability science (SS) is an 'emerging field of research dealing with the interactions between natural and social systems, and with how those interactions affect the challenge of sustainability: meeting the needs of present and future generations while substantially reducing poverty and conserving the planet's life support systems' (Kates, 2011; Clark, 2007). Bettencourt & Kaur (2011) identified more than 20,000 scientific papers published on SS topics since the 1980s with more than 35,000 distinct authors. They estimated that the field is currently growing exponentially, with the number of authors doubling approximately every 8 years. These scholars are undoubtedly using and generating a vast quantity and variety of data and information for both SS research and applications. Unfortunately we know little about what data the SS community is actually using, and whether or not the data that SS scholars generate are being preserved for future use. Moreover, since much SS research is conducted by cross-disciplinary, multi-institutional teams, often scattered around the world, there could well be increased risks of data loss, reduced data quality, inadequate documentation, and poor long-term access and usability. Capabilities and processes therefore need to be established today to support continual, reliable, and efficient preservation of and access to SS data in the future, especially so that they can be reused in conjunction with future data and for new studies not conceived in the original data collection activities. Today's long-term data stewardship challenges include establishing sustainable data governance to facilitate continuing management, selecting data to ensure that limited resources are focused on high priority SS data holdings, securing sufficient rights to allow unforeseen uses, and preparing data to enable use by future communities whose specific research and information needs are not yet known. Adopting sustainable models for archival

  14. Comparative Multi-Criteria Assessment of Climate Policies and Sustainable Development Strategies in Cameroon: Towards a GIS Decision-Support Tool for the Design of an Optimal REDD+ Strategy

    Directory of Open Access Journals (Sweden)

    Anderson Gwanyebit Kehbila

    2014-09-01

    Full Text Available Cameroon is committed to reducing emissions from deforestation and forest degradation plus conservation, sustainable management of forests and enhancement of carbon stocks (REDD+. To achieve this goal, the government has introduced a series of policy reforms and formulated a number of key strategic planning documents to advance the REDD+ readiness process in Cameroon. This paper assesses the extent to which major cross-sectoral policies support or impede the development and implementation of an optimal REDD+ strategy in Cameroon from a comparative multi-criteria perspective. Study results reveal that a majority of the policy instruments reviewed appeared to be less prescriptive in terms of any tangible REDD+ strategy, as they do not have provisions for tangible measures to reduce deforestation and forest degradation. Given the lack of adequate flexibility, prompt review and responsiveness of these cross-sectoral policies to adapt themselves to new realities and respond to a changing environment, this paper introduces a GIS-REDD+ decision support system (GIS-REDD+DSS that is necessary to support the adaptive element of an adaptive REDD+ strategy in Cameroon. The GIS-REDD+DSS, an electronic REDD+agri intermediary hub, serves the following purpose: (1 host a database of locally-relevant climate information, improved input technologies, best practices as well as land use and forest cover geo-spatial maps; (2 host a virtual economic tool that performs economic valuations (costs and benefits and financial analysis of REDD+agri projects to aid investment decision-making; and (3 host an electronic marketplace to mediate any-to-any transactions among REDD+agri project developers, service providers, input suppliers, private and institutional investors and buyers (wholesalers and retailers, thereby creating value in two ways: aggregation and matching. This decision support tool, we argue, is a fundamental prerequisite for “policy and REDD+ safeguard

  15. Collaborative design of parametric sustainable architecture

    NARCIS (Netherlands)

    Hubers, H.

    2011-01-01

    Sustainable architecture is complex. Many aspects, differently important to many stakeholders, are to be optimized. BIM should be used for this. Building Information Modelling is a collaborative process where all stakeholders integrate and optimize their information in a digital 3D model. Sometimes

  16. Collaborative Design of Parametric Sustainable Architecture

    NARCIS (Netherlands)

    Hubers, J.C.

    2012-01-01

    Sustainable architecture is complex. Many aspects, differently important to many stakeholders, are to be optimized. BIM should be used for this. Building Information Modellingis a collaborative process where all stakeholders integrate and optimize their information in a digital 3D model. Sometimes

  17. Collaborative Design of Parametric Sustainable Architecture

    NARCIS (Netherlands)

    Hubers, J.C.

    2012-01-01

    Sustainable architecture is complex. Many aspects, differently important to many stakeholders, are to be optimized. BIM should be used for this. Building Information Modellingis a collaborative process where all stakeholders integrate and optimize their information in a digital 3D model. Sometimes i

  18. Population genetic analysis of microsatellite variation of guppies (Poecilia reticulata) in Trinidad and Tobago: evidence for a dynamic source-sink metapopulation structure, founder events and population bottlenecks.

    Science.gov (United States)

    Barson, N J; Cable, J; Van Oosterhout, C

    2009-03-01

    Riverine fish populations are traditionally considered to be highly structured and subject to strong genetic drift. Here, we use microsatellites to analyse the population structure of the guppy (Poecilia reticulata), focussing on the headwater floodplain area of the Caroni drainage in Trinidad. We also analyse the population genetics of guppies in the Northern Drainage in Trinidad, a habitat characterized by rivers flowing directly into the sea, and a small isolated population in Tobago. Upland Caroni populations are highly differentiated and display low levels of genetic diversity. However, we found no evidence to suggest that these upland populations experienced recent population crashes and the populations appear to approach mutation-drift equilibrium. Dominant downstream migration over both short- and long-time frames has a strong impact on the population genetics of lowland Caroni populations. This drainage system could be considered a source-sink metapopulation, with the tributary furthest downstream representing a 'super sink', receiving immigrants from rivers upstream in the drainage. Moreover, the effective population size in the lowlands is surprisingly low in comparison with the apparently large census population sizes.

  19. Combined action of time-delay and colored cross-associated multiplicative and additive noises on stability and stochastic resonance for a stochastic metapopulation system

    Science.gov (United States)

    Wang, Kang-Kang; Zong, De-Cai; Wang, Ya-Jun; Li, Sheng-Hong

    2016-05-01

    In this paper, the transition between the stable state of a big density and the extinction state and stochastic resonance (SR) for a time-delayed metapopulation system disturbed by colored cross-correlated noises are investigated. By applying the fast descent method, the small time-delay approximation and McNamara and Wiesenfeld's SR theory, we investigate the impacts of time-delay, the multiplicative, additive noises and colored cross-correlated noise on the SNR and the shift between the two states of the system. Numerical results show that the multiplicative, additive noises and time-delay can all speed up the transition from the stable state to the extinction state, while the correlation noise and its correlation time can slow down the extinction process of the population system. With respect to SNR, the multiplicative noise always weakens the SR effect, while noise correlation time plays a dual role in motivating the SR phenomenon. Meanwhile, time-delay mainly plays a negative role in stimulating the SR phenomenon. Conversely, it could motivate the SR effect to increase the strength of the cross-correlation noise in the SNR-β plot, while the increase of additive noise intensity will firstly excite SR, and then suppress the SR effect.

  20. Sustainable Scientists

    Energy Technology Data Exchange (ETDEWEB)

    Mills, Evan

    2008-12-31

    Scientists are front and center in quantifying and solving environmental problems. Yet, as a spate of recent news articles in scientific journals point out, much can be done to enhance sustainability within the scientific enterprise itself, particularly by trimming the energy use associated with research facilities and the equipment therein (i,ii,iii, iv). Sponsors of research unwittingly spend on the order of $10 billion each year on energy in the U.S. alone, and the underlying inefficiencies drain funds from the research enterprise while causing 80 MT CO2-equivalent greenhouse-gas emissions (see Box). These are significant sums considering the opportunity costs in terms of the amount of additional research that could be funded and emissions that could be reduced if the underlying energy was used more efficiently. By following commercially proven best practices in facility design and operation, scientists--and the sponsors of science--can cost-effectively halve these costs, while doing their part to put society on alow-carbon diet.

  1. Sustainable agriculture - selected papers

    OpenAIRE

    Krasowicz, Stanisław; Wrzaszcz, Wioletta; Zegar, Jozef St.

    2007-01-01

    The concept of research on socially sustainable agriculture. Features of sustainable agriculture. Sustainability of private farms in the light of selected criteria. Subsistence agricultural holdings and the sustainable development of agriculture. Sustainable farms in the light of the FADN data. Description of organic holdings in Poland.

  2. Benchmarking the sustainability performance of the Brazilian non-GM and GM soybean meal chains: An indicator-based approach

    NARCIS (Netherlands)

    Gaitan Cremaschi, D.; Pashaei Kamali, F.; Evert, van F.K.; Meuwissen, M.P.M.; Oude Lansink, A.G.J.M.

    2015-01-01

    A commonly accepted approach for measuring the sustainability of agricultural products is the first step toward treating traded products differentially according to their sustainability. If we were able to measure sustainability, business stakeholders could optimize food production chains, consumers

  3. Benchmarking the sustainability performance of the Brazilian non-GM and GM soybean meal chains: An indicator-based approach

    NARCIS (Netherlands)

    Gaitan Cremaschi, D.; Pashaei Kamali, F.; Evert, van F.K.; Meuwissen, M.P.M.; Oude Lansink, A.G.J.M.

    2015-01-01

    A commonly accepted approach for measuring the sustainability of agricultural products is the first step toward treating traded products differentially according to their sustainability. If we were able to measure sustainability, business stakeholders could optimize food production chains, consumers

  4. Sustainable Development of Food Safety

    DEFF Research Database (Denmark)

    Fabech, B.; Georgsson, F.; Gry, Jørn

    The Nordic countries, Denmark, Finland, Iceland, Norway and Sweden published a strategy for sustainable developments for 2001-2004. The strategy for 2005-2008 has 10 goals and some selected indicators. The 10 goals set for 2005-2008 are : - Improved efforts for animal health and welfare in relation...... - Strengthen scientific knowledge of food safety - Strengthen consumer knowledge The goals for sustainable development of food safety are listed from farm to fork". All of the steps and areas are important for food safety and consumer protection. Initiatives are needed in all areas. Many of the goals...... in other areas. It should be emphasized that an indicator will be an excellent tool to assess the efficacy of initiatives started to achieve a goal. Conclusions from the project are: - Sustainable development in food safety is important for humanity - Focus on the crucial goals would optimize the efforts...

  5. Sustainable NREL - Site Sustainability Plan FY 2015

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2015-01-01

    NREL's Site Sustainability Plan FY 2015 reports on sustainability plans for the lab for the year 2015 based on Executive Order Goals and provides the status on planned actions cited in the FY 2014 report.

  6. Towards Sustainable Consumption and Production

    DEFF Research Database (Denmark)

    Ulku, M. Ali; Hsuan, Juliana

    2017-01-01

    Concern for unsustainable development has peaked, and promoting and devising sustainable production and consumption is vital. Therefore, via an analytical model, we examine the impact of modularity and consumer sensitivity to sustainability on the pricing decisions of two competing firms. Consider....... For such a consumer-driven demand setting, we develop a model and solve to optimality a single-stage, non-cooperative game where both firms simultaneously set their competitive prices. In addition to analytical expressions for the optimal prices and the profits for both firms, we provide structural results...... and numerical examples to render practical insights: The refund rate has a strong impact on profits; sensitivity of product greenness can be increased by conscientious advertising, and the reusability of modular parts encourages lower pricing and higher market share. We assert that modularity is a strong...

  7. Sustainability : Intergeneration Equity and Environment

    Energy Technology Data Exchange (ETDEWEB)

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

    2001-06-01

    Regarding intergenerational equity as prerequisite for sustainability, we derive an optimal investment rule for intergenerational equity from an optimization model allowing for capital accumulation and pollution. This rule provides a condition for intergenerational equity such that an economy maintains constant net value of investment the difference between the physical capital investment value and the environmental resource depletion(pollution) value. This rule is more generalized condition for intergenerational equity than the 'keep capital intact' rule suggested by Hartwick(1977) and Solow(1999), in a sense that this rule includes their condition as a special. Also, we expect this rule to offer an empirical measure of sustainability. In addition, we discuss a variety of recent environmental issues in practice, especially associated with the implications from the rule. (author). 13 refs.

  8. Sustainability in Transport Planning

    DEFF Research Database (Denmark)

    Gudmundsson, Henrik; Greve, Carsten

    Contribution to session J: Joint University Sustainability Initiatives. This session will provide an inspiring overview of interdisciplinary research and teaching activities on sustainability bridging DTU, KU, and CBS, and introduce the joint collaboration Copenhagen Sustainability Initiative (COSI...

  9. Sustainability : Politics and governance

    NARCIS (Netherlands)

    Heinrichs, Harald; Biermann, Frank|info:eu-repo/dai/nl/176991662

    2016-01-01

    he article gives an overview of global sustainability policy and politics. It is shown how international policy making on sustainable development has progressed from environmental policy toward recent approaches of Earth system governance. Key challenges of international sustainability politics are

  10. Sustainability : Politics and governance

    NARCIS (Netherlands)

    Heinrichs, Harald; Biermann, Frank

    2016-01-01

    he article gives an overview of global sustainability policy and politics. It is shown how international policy making on sustainable development has progressed from environmental policy toward recent approaches of Earth system governance. Key challenges of international sustainability politics are

  11. Sustainability in Transport Planning

    DEFF Research Database (Denmark)

    Gudmundsson, Henrik; Greve, Carsten

    Contribution to session J: Joint University Sustainability Initiatives. This session will provide an inspiring overview of interdisciplinary research and teaching activities on sustainability bridging DTU, KU, and CBS, and introduce the joint collaboration Copenhagen Sustainability Initiative (COSI...

  12. Sustainable diets within sustainable food systems.

    Science.gov (United States)

    Meybeck, Alexandre; Gitz, Vincent

    2017-02-01

    Sustainable diets and sustainable food systems are increasingly explored by diverse scientific disciplines. They are also recognised by the international community and called upon to orient action towards the eradication of hunger and malnutrition and the fulfilment of sustainable development goals. The aim of the present paper is to briefly consider some of the links between these two notions in order to facilitate the operationalisation of the concept of sustainable diet. The concept of sustainable diet was defined in 2010 combining two totally different perspectives: a nutrition perspective, focused on individuals, and a global sustainability perspective, in all its dimensions: environmental, economic and social. The nutrition perspective can be easily related to health outcomes. The global sustainability perspective is more difficult to analyse directly. We propose that it be measured as the contribution of a diet to the sustainability of food systems. Such an approach, covering the three dimensions of sustainability, enables identification of interactions and interrelations between food systems and diets. It provides opportunities to find levers of change towards sustainability. Diets are both the results and the drivers of food systems. The drivers of change for those variously involved, consumers and private individuals, are different, and can be triggered by different dimensions (heath, environment, social and cultural). Combining different dimensions and reasons for change can help facilitate the transition to sustainable diets, recognising the food system's specificities. The adoption of sustainable diets can be facilitated and enabled by food systems, and by appropriate policies and incentives.

  13. Sustainable Campus: Engaging the Community in Sustainability

    Science.gov (United States)

    Too, Linda; Bajracharya, Bhishna

    2015-01-01

    Purpose: The purpose of this paper is to identify the major factors necessary for engaging university campus community in sustainability. While general awareness in sustainability issues has improved in recent years through mass media coverage, this knowledge is not always translated into actual sustainable practice. Studies have indicated that…

  14. Sustainable Campus: Engaging the Community in Sustainability

    Science.gov (United States)

    Too, Linda; Bajracharya, Bhishna

    2015-01-01

    Purpose: The purpose of this paper is to identify the major factors necessary for engaging university campus community in sustainability. While general awareness in sustainability issues has improved in recent years through mass media coverage, this knowledge is not always translated into actual sustainable practice. Studies have indicated that…

  15. Textiles and clothing sustainability sustainable technologies

    CERN Document Server

    2017-01-01

    This is the first book to deal with the innovative technologies in the field of textiles and clothing sustainability. It details a number of sustainable and innovative technologies and highlights their implications in the clothing sector. There are currently various measures to achieve sustainability in the textiles and the clothing industry, including innovations in the manufacturing stage, which is the crux of this book.

  16. Sustainable Aluminium Systems

    Directory of Open Access Journals (Sweden)

    Sergio R. Ermolli

    2010-09-01

    Full Text Available In the present paper, an analytical presentation of some popular aluminium systems that contribute to sustainability of structures is presented. Special emphasis has been given to the properties of aluminium, while the influence of these systems in the overall performance of the structure regarding environment and economy is described. In particular, characteristics of aluminium elements such as high reflectivity and recyclability and their role in life cycle analysis (LCA are analyzed. The connections between energy efficiency and conservation of buildings and aluminium application are also discussed. Building applications such as curtain walls, window frames and facade sheets are presented and thoroughly investigated, considering their environmental and economic aspects. Furthermore, many innovative techniques that use aluminium elements in collaboration with other systems in order to produce renewable energy, such as solar panels and photovoltaics, are introduced. Finally, environmental innovations such as optimized ventilation mechanisms and light and shade management systems based on aluminium members are presented.

  17. Changing perspectives on biodiversity conservation: from species protection to regional sustainability

    Institute of Scientific and Technical Information of China (English)

    Jianguo Wu

    2008-01-01

    Biodiversity is the basis for ecosystem goods and services that provide for human survival and prosperity. With a rapidly increasing human population and its demands for natural resources, landscapes are being fragmented, habitats are being destroyed, and biodiversity is declining. How can biodiversity be effectively conserved in the face of increasing human pressures? In this paper, Ⅰ review changing perspectives on biodiversity conservation, and discuss their relevance to the practice of biodiversity conservation. The major points include: The notion of balance of nature is a myth rather than a scientific concept; the theory of island biogeography is useful heuristically but flawed practically; the SLOSS debate is intriguing in theory but irrelevant in reality; the concept of minimum viable population and population viability analysis are useful, but technically inefficient and conceptually inadequate; metapopulation theory is mathematically elegant but ecologically oversimplistic; and integrative perspectives and approaches for biodiversity conservation are needed that incorporate insights from landscape ecology and sustainability science. Ⅰ further discuss some key principles for regional conservation planning, and argue that the long-term success of biodiversity conservation in any region will ultimately depend on the economic and social sustainability of that region. Both research and practice in biodiversity conservation, therefore, need to adopt a broader perspective of sustainability.

  18. Maternally Derived Immunity Extends Swine Influenza A Virus Persistence within Farrow-to-Finish Pig Farms: Insights from a Stochastic Event-Driven Metapopulation Model.

    Science.gov (United States)

    Cador, Charlie; Rose, Nicolas; Willem, Lander; Andraud, Mathieu

    Swine Influenza A Viruses (swIAVs) have been shown to persist in farrow-to-finish pig herds with repeated outbreaks in successive batches, increasing the risk for respiratory disorders in affected animals and being a threat for public health. Although the general routes of swIAV transmission (i.e. direct contact and exposure to aerosols) were clearly identified, the transmission process between batches is still not fully understood. Maternally derived antibodies (MDAs) were stressed as a possible factor favoring within-herd swIAV persistence. However, the relationship between MDAs and the global spread among the different subpopulations in the herds is still lacking. The aim of this study was therefore to understand the mechanisms induced by MDAs in relation with swIAV spread and persistence in farrow-to-finish pig herds. A metapopulation model has been developed representing the population dynamics considering two subpopulations-breeding sows and growing pigs-managed according to batch-rearing system. This model was coupled with a swIAV-specific epidemiological model, accounting for partial passive immunity protection in neonatal piglets and an immunity boost in re-infected animals. Airborne transmission was included by a between-room transmission rate related to the current prevalence of shedding pigs. Maternally derived partial immunity in piglets was found to extend the duration of the epidemics within their batch, allowing for efficient between-batch transmission and resulting in longer swIAV persistence at the herd level. These results should be taken into account in the design of control programmes for the spread and persistence of swIAV in swine herds.

  19. Distribution of two species of sea snakes, Aipysurus laevis and Emydocephalus annulatus, in the southern Great Barrier Reef: metapopulation dynamics, marine protected areas and conservation

    Science.gov (United States)

    Lukoschek, V.; Heatwole, H.; Grech, A.; Burns, G.; Marsh, H.

    2007-06-01

    Aipysurus laevis and Emydocephalus annulatus typically occur in spatially discrete populations, characteristic of metapopulations; however, little is known about the factors influencing the spatial and temporal stability of populations or whether specific conservation strategies, such as networks of marine protected areas, will ensure the persistence of species. Classification tree analyses of 35 years of distribution data (90 reefs, surveyed 1-11 times) in the southern Great Barrier Reef (GBR) revealed that longitude was a major factor determining the status of A. laevis on reefs (present = 38, absent = 38 and changed = 14). Reef exposure and reef area were also important; however, these factors did not specifically account for the population fluctuations and the recent local extinctions of A. laevis in this region. There were no relationships between the status of E. annulatus (present = 16, absent = 68 and changed = 6) and spatial or physical variables. Moreover, prior protection status of reefs did not account for the distribution of either species. Biotic factors, such as habitat and prey availability and the distribution of predators, which may account for the observed patterns of distribution, are discussed. The potential for inter-population exchange among sea snake populations is poorly understood, as is the degree of protection that will be afforded to sea snakes by the recently implemented network of No-take areas in the GBR. Data from this study provide a baseline for evaluating the responses of A. laevis and E. annulatus populations to changes in biotic factors and the degree of protection afforded on reefs within an ecosystem network of No-take marine protected areas in the southern GBR.

  20. Maternally Derived Immunity Extends Swine Influenza A Virus Persistence within Farrow-to-Finish Pig Farms: Insights from a Stochastic Event-Driven Metapopulation Model

    Science.gov (United States)

    Cador, Charlie; Rose, Nicolas; Willem, Lander; Andraud, Mathieu

    2016-01-01

    Swine Influenza A Viruses (swIAVs) have been shown to persist in farrow-to-finish pig herds with repeated outbreaks in successive batches, increasing the risk for respiratory disorders in affected animals and being a threat for public health. Although the general routes of swIAV transmission (i.e. direct contact and exposure to aerosols) were clearly identified, the transmission process between batches is still not fully understood. Maternally derived antibodies (MDAs) were stressed as a possible factor favoring within-herd swIAV persistence. However, the relationship between MDAs and the global spread among the different subpopulations in the herds is still lacking. The aim of this study was therefore to understand the mechanisms induced by MDAs in relation with swIAV spread and persistence in farrow-to-finish pig herds. A metapopulation model has been developed representing the population dynamics considering two subpopulations—breeding sows and growing pigs—managed according to batch-rearing system. This model was coupled with a swIAV-specific epidemiological model, accounting for partial passive immunity protection in neonatal piglets and an immunity boost in re-infected animals. Airborne transmission was included by a between-room transmission rate related to the current prevalence of shedding pigs. Maternally derived partial immunity in piglets was found to extend the duration of the epidemics within their batch, allowing for efficient between-batch transmission and resulting in longer swIAV persistence at the herd level. These results should be taken into account in the design of control programmes for the spread and persistence of swIAV in swine herds. PMID:27662592

  1. SNP design from 454 sequencing of Podosphaera plantaginis transcriptome reveals a genetically diverse pathogen metapopulation with high levels of mixed-genotype infection.

    Directory of Open Access Journals (Sweden)

    Charlotte Tollenaere

    Full Text Available BACKGROUND: Molecular tools may greatly improve our understanding of pathogen evolution and epidemiology but technical constraints have hindered the development of genetic resources for parasites compared to free-living organisms. This study aims at developing molecular tools for Podosphaera plantaginis, an obligate fungal pathogen of Plantago lanceolata. This interaction has been intensively studied in the Åland archipelago of Finland with epidemiological data collected from over 4,000 host populations annually since year 2001. PRINCIPAL FINDINGS: A cDNA library of a pooled sample of fungal conidia was sequenced on the 454 GS-FLX platform. Over 549,411 reads were obtained and annotated into 45,245 contigs. Annotation data was acquired for 65.2% of the assembled sequences. The transcriptome assembly was screened for SNP loci, as well as for functionally important genes (mating-type genes and potential effector proteins. A genotyping assay of 27 SNP loci was designed and tested on 380 infected leaf samples from 80 populations within the Åland archipelago. With this panel we identified 85 multilocus genotypes (MLG with uneven frequencies across the pathogen metapopulation. Approximately half of the sampled populations contain polymorphism. Our genotyping protocol revealed mixed-genotype infection within a single host leaf to be common. Mixed infection has been proposed as one of the main drivers of pathogen evolution, and hence may be an important process in this pathosystem. SIGNIFICANCE: The developed SNP panel offers exciting research perspectives for future studies in this well-characterized pathosystem. Also, the transcriptome provides an invaluable novel genomic resource for powdery mildews, which cause significant yield losses on commercially important crops annually. Furthermore, the features that render genetic studies in this system a challenge are shared with the majority of obligate parasitic species, and hence our results provide

  2. Assessing sustainable remediation frameworks using sustainability principles.

    Science.gov (United States)

    Ridsdale, D Reanne; Noble, Bram F

    2016-12-15

    The remediation industry has grown exponentially in recent decades. International organizations of practitioners and remediation experts have developed several frameworks for integrating sustainability into remediation projects; however, there has been limited attention to how sustainability is approached and operationalized in sustainable remediation frameworks and practices - or whether sustainability plays any meaningful role at all in sustainable remediation. This paper examines how sustainability is represented in remediation frameworks and the guidance provided for practical application. Seven broad sustainability principles and review criteria are proposed and applied to a sample of six international remediation frameworks. Not all review criteria were equally satisfied and none of the frameworks fully met all criteria; however, the best performing frameworks were those identified as sustainability remediation frameworks. Intra-generational equity was addressed by all frameworks. Integrating social, economic and biophysical components beyond triple-bottom-line indicators was explicitly addressed only by the sustainable remediation frameworks. No frameworks provided principle- or rule-based guidance for dealing with trade-offs in sustainability decisions. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Technology and sustainability

    NARCIS (Netherlands)

    Kroeze, C.; Boersema, J.J.; Tellegen, E.; Cremers, A.

    2011-01-01

    In ten essays, this book addresses a broad range of issues related to the interplay of sustainability and technology. How do population growth and technology relate to sustainable development? Can globalization be reconciled with sustainable development? Is sustainability a subjective or an

  4. Modeling Sustainment Investment

    Science.gov (United States)

    2015-05-01

    forecast the consequences of various alternatives? Sustainment Investment: the Problem Operations Supplying the fleet, customer support, etc...Modeling Sustainment Investment May 2015 © 2015 Carnegie Mellon University Context We are managing the sustainment of a system. • Some modernization ...Modeling Sustainment Investment May 2015 © 2015 Carnegie Mellon University The process is inside the gray box. Customers are outside. Work input

  5. Organizing for Sustainability

    Science.gov (United States)

    Brown, William M.; Hamburger, Michael W.

    2012-01-01

    A successful campus sustainability effort catalyzes broad engagement of the campus community and integration of sustainability principles into the academic and operational components of campus life. Although many universities have embraced sustainability as a new core value, others have been more sluggish in adopting sustainability principles to…

  6. 2010 Campus Sustainability Review

    Science.gov (United States)

    Association for the Advancement of Sustainability in Higher Education, 2011

    2011-01-01

    With this review of campus sustainability efforts in 2010, the editors aim to give readers--those who are often immersed in the day-to-day particulars of sustainability efforts--the same chance to take a step back and take a broader look at where they stand with sustainability in higher education. This inaugural 2010 Campus Sustainability Review…

  7. Technology and sustainability

    NARCIS (Netherlands)

    Kroeze, C.; Boersema, J.J.; Tellegen, E.; Cremers, A.

    2011-01-01

    In ten essays, this book addresses a broad range of issues related to the interplay of sustainability and technology. How do population growth and technology relate to sustainable development? Can globalization be reconciled with sustainable development? Is sustainability a subjective or an objectiv

  8. Organizing for Sustainability

    Science.gov (United States)

    Brown, William M.; Hamburger, Michael W.

    2012-01-01

    A successful campus sustainability effort catalyzes broad engagement of the campus community and integration of sustainability principles into the academic and operational components of campus life. Although many universities have embraced sustainability as a new core value, others have been more sluggish in adopting sustainability principles to…

  9. 2010 Campus Sustainability Review

    Science.gov (United States)

    Association for the Advancement of Sustainability in Higher Education, 2011

    2011-01-01

    With this review of campus sustainability efforts in 2010, the editors aim to give readers--those who are often immersed in the day-to-day particulars of sustainability efforts--the same chance to take a step back and take a broader look at where they stand with sustainability in higher education. This inaugural 2010 Campus Sustainability Review…

  10. Externality or sustainability economics?

    Energy Technology Data Exchange (ETDEWEB)

    Bergh, Jeroen C.J.M. van den [ICREA, Barcelona (Spain); Department of Economics and Economic History and Institute for Environmental Science and Technology, Universitat Autonoma de Barcelona (Spain)

    2010-09-15

    In an effort to develop 'sustainability economics' Baumgaertner and Quaas (2010) neglect the central concept of environmental economics-'environmental externality'. This note proposes a possible connection between the concepts of environmental externality and sustainability. In addition, attention is asked for other aspects of 'sustainability economics', namely the distinction weak/strong sustainability, spatial sustainability and sustainable trade, distinctive sustainability policy, and the ideas of early 'sustainability economists'. I argue that both sustainability and externalities reflect a systems perspective and propose that effective sustainability solutions require that more attention is given to system feedbacks, notably other-regarding preferences and social interactions, and energy and environmental rebound. The case of climate change and policy is used to illustrate particular statements. As a conclusion, a list of 20 insights and suggestions for research is offered. (author)

  11. Optimally Stopped Optimization

    Science.gov (United States)

    Vinci, Walter; Lidar, Daniel A.

    2016-11-01

    We combine the fields of heuristic optimization and optimal stopping. We propose a strategy for benchmarking randomized optimization algorithms that minimizes the expected total cost for obtaining a good solution with an optimal number of calls to the solver. To do so, rather than letting the objective function alone define a cost to be minimized, we introduce a further cost-per-call of the algorithm. We show that this problem can be formulated using optimal stopping theory. The expected cost is a flexible figure of merit for benchmarking probabilistic solvers that can be computed when the optimal solution is not known and that avoids the biases and arbitrariness that affect other measures. The optimal stopping formulation of benchmarking directly leads to a real-time optimal-utilization strategy for probabilistic optimizers with practical impact. We apply our formulation to benchmark simulated annealing on a class of maximum-2-satisfiability (MAX2SAT) problems. We also compare the performance of a D-Wave 2X quantum annealer to the Hamze-Freitas-Selby (HFS) solver, a specialized classical heuristic algorithm designed for low-tree-width graphs. On a set of frustrated-loop instances with planted solutions defined on up to N =1098 variables, the D-Wave device is 2 orders of magnitude faster than the HFS solver, and, modulo known caveats related to suboptimal annealing times, exhibits identical scaling with problem size.

  12. Optimization and Optimal Control

    CERN Document Server

    Chinchuluun, Altannar; Enkhbat, Rentsen; Tseveendorj, Ider

    2010-01-01

    During the last four decades there has been a remarkable development in optimization and optimal control. Due to its wide variety of applications, many scientists and researchers have paid attention to fields of optimization and optimal control. A huge number of new theoretical, algorithmic, and computational results have been observed in the last few years. This book gives the latest advances, and due to the rapid development of these fields, there are no other recent publications on the same topics. Key features: Provides a collection of selected contributions giving a state-of-the-art accou

  13. A THEORETICAL DISCUSSION ON TYPES AND MEASUREMENT OF SUSTAINABLE DEVELOPMENT

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Classifying the types and measuring sustainable development are important contents of theoretical studies on sustainable development. Scientifically reflecting the characteristics of sustainable development and favorably classifying the types of sustainable development are the basis and objective of measuring sustainable development. By using the methods of coordinatively analyzing man-land relationship and economic analysis, especially by combining with constant elasticity of substitution (CES) production function, this paper advances average sustainable gross domestic production (ASGDP), inquires into the mutually coordinative and interdependent relationship between humane capital and natural capital in the process of sustainable development. It also sets up an index system of measuring sustainable development andatypesystemofsustainabledevelopment. then accordingto this index system, if firstly classifies the sustainable development, moderate sustainable development, and strong sustainable development, and it also discuss them theoretical significance. Secondly, it probes into the minimum cost, structure optimization and sustainable development. At last, it discuss the type classification of sustainable development on development sequence, and points out theoretically the amount of transitions among 8 basic regional sustainable development types is 56. in the process of productive expansion this transition type embodies the input increase of humane capital is greatly larger than that of natural capital. On the contrary, economized humane capital transition is a result of progressively decreasing marginal rate of technical substitution of humane capital to natural capital.

  14. Sustainable labour participation and sustainable careers

    NARCIS (Netherlands)

    Semeijn, J.; Dam, K. van; Vuuren, T. van; Heijden, B.I.J.M. van der

    2015-01-01

    Changing economic and social circumstances, as well as changing demographics are leading to a growing interest in sustainable labour participation of workers. In terms of business considerations, sustainable labour participation refers to people value, or more social value, of business practice and

  15. Sustaining Rural Communities through Sustainable Agriculture.

    Science.gov (United States)

    Ikerd, John

    A 5-year collaborative project between Missouri, Michigan State, and Nebraska Universities to provide new opportunities for rural community self-development through sustainable agriculture had mixed results. This happened because community members did not understand the principles of sustainability, and because the extension education system was…

  16. Sustainable Marketing : The Importance of Being a Sustainable Business

    OpenAIRE

    Reutlinger, Janina

    2012-01-01

    This thesis deals with sustainable marketing, as well as the necessity for more sustainability. The purpose of this thesis was to determine the importance of sustainable marketing for companies. The theoretical part is divided into sustainability and sustainable marketing. Sustainability covers current issues and sustainable development, which form a background for a better understanding of sustainable marketing. Sustainable marketing includes a definition of the concept, as well as susta...

  17. Rapid and sustained cost management

    Energy Technology Data Exchange (ETDEWEB)

    Hanson, D. [Accenture, New York, NY (United States)

    2009-07-01

    Accenture helps clients develop comprehensive, process-driven strategies for rapid and sustained cost management that leverage deep insights and analytics. This approach enables companies to gain operating cost advantages by rationalizing, simplifying and automating current operating capabilities. It drives structural cost advantages by optimizing business mix, capital structure, organizational structure and geographic presence. This paper discussed how successful companies achieve high performance during times of economic turmoil. It also discussed the value of the winner's strategy in terms of rapid and sustained cost management (RSCM). It discussed how Accenture operates and its leveraged capabilities, improved efficiency, margins and cash flow while maintaining customer service levels. Building structural advantage and the Accenture difference were also discussed. It was concluded that RSCM is one vital way that Accenture can help companies achieve success. 4 figs.

  18. Sustainable process synthesis–intensification

    DEFF Research Database (Denmark)

    Babi, Deenesh Kavi; Holtbruegge, Johannes; Lutze, Philip

    2015-01-01

    Chemical industry is facing global challenges such as the need to find sustainable production processes.Process intensification as part of process synthesis has the potential to find truly innovative and moresustainable solutions. In this paper, a computer-aided, multi-level, multi-scale framework...... approach andrelated synthesis tools. In the second, “design” stage, the processing route from the first stage is furtherdeveloped and a base case design is established and analyzed. In the third, “innovation” stage, moresustainable innovative solutions are determined. The application of the framework...... for synthesis,design and intensification of processes, for identifying more sustainable alternatives is presented. Withinthe framework, a three stage work-flow has been implemented where, in the first “synthesis” stage anoptimal processing route is synthesized through a network superstructure optimization...

  19. Sustainable Development of Food Safety

    DEFF Research Database (Denmark)

    Fabech, B.; Georgsson, F.; Gry, Jørn

    to food safety - Strengthen efforts against zoonoses and pathogenic microorganisms - Strengthen safe food handling and food production in industry and with consumers - Restrict the occurrence of chemical contaminants and ensure that only well-examined production aids, food additives and flavours are used...... - Strengthen scientific knowledge of food safety - Strengthen consumer knowledge The goals for sustainable development of food safety are listed from farm to fork". All of the steps and areas are important for food safety and consumer protection. Initiatives are needed in all areas. Many of the goals...... in other areas. It should be emphasized that an indicator will be an excellent tool to assess the efficacy of initiatives started to achieve a goal. Conclusions from the project are: - Sustainable development in food safety is important for humanity - Focus on the crucial goals would optimize the efforts...

  20. Gene migration for re-emerging amebiasis in Iran's northwest-Iraq borders: a microevolutionary scale for reflecting epidemiological drift of Entamoeba histolytica metapopulations.

    Science.gov (United States)

    Mohammadzadeh, Asad; Spotin, Adel; Mahami-Oskouei, Mahmoud; Haghighi, Ali; Zebardast, Nozhat; Kohansal, Kobra

    2017-01-01

    In the microevolutionary scales of Entamoeba isolates, the gene migration shows how Entamoeba spp. has epidemiologically drifted among border countries. Five hundred fecal samples were taken from patients suffering gastrointestinal disorders, abdominal pain, and diarrhea at Saggez, northwest Iran located within the border Iraq country. Following parasitological techniques, DNA samples were extracted and amplified by polymerase chain reaction (PCR) of 18S rRNA region to identify Entamoeba infections. To distinguish the Entamoeba spp., a multiplex PCR was conducted. Amplicons were sequenced to reconfirm their heterogeneity traits and phylogenetic analysis. Additionally, Entamoeba histolytica sequences of Iraq were retrieved from GenBank database. The suspected isolates were diagnosed as E. histolytica (2.2 %), Entamoeba moshkovskii (1 %), and Entamoeba dispar (0.4 %). Mixed Entamoeba infections did not detect among isolates. A parsimonious network of the sequence haplotypes displayed star-like features in the overall isolates containing E.h1, E.d2, and E.m3 as the most common haplotypes. According to analysis of molecular variance (AMOVA) test, high partial value of haplotype diversity (0.700 to 0.800) of E. histolytica was shown the total genetic variability within populations while nucleotide diversity was low among Iranian and Iraqi metapopulations. Neutrality indices of the 18S rRNA were shown negative values in E. histolytica populations which indicating significant deviations from neutrality. A pairwise fixation index (F-statistics [Fst]) as a degree of gene flow had a low value for all populations (0.001) while the number of migrants was 2.48. The statistically Fst value indicates that E. histolytica isolates are not genetically differentiated among shared isolates of Iran and Iraq. Occurrence of E.h1 between two regional populations indicates that there is dawn of Entamoeba flow due to transfer of alleles from one population to another population through

  1. Action Research for Sustainability

    DEFF Research Database (Denmark)

    Egmose, Jonas

    to provide local citizens with a greater say in the future of urban sustainability research, this book shows how action research can make important methodological contributions to processes of social learning between citizens and scientists by enabling free spaces in peoples everyday life and within academia...... by analysing processes of social learning. The book addresses the need to move towards sustainability at societal level as a democratic challenge questioning the way we live on planet earth. By conceptualising sustain-ability as an immanent and emergent ability of ecological and social life, continuously...... to renew itself without eroding its own foundation of existence, it argues that since sustainability cannot be invented but only supported (or eroded) by science, we need to reframe science in the role of sustaining sustain-ability. Through analyses of a three year action research programme, aiming...

  2. The Sustainable Shopper

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    Many industries, including textiles, have modernized their supply chains by implementing sustainable practices in product manufacturing that decrease the use of water, energy and chemicals. While sustainable product manufacturing is important to U.S. consumers,

  3. Handbook of sustainable engineering

    CERN Document Server

    Lee, Kun-Mo

    2013-01-01

    "The efficient utilization of energy, sustainable use of natural resources, and large-scale adoption of sustainable technologies is the key to a sustainable future. The Handbook of Sustainable Engineering provides tools that will help us achieve these goals". Nobel Prize Winner Dr. R.K. Pauchauri, Chairman, UN Intergovernmental Panel on Climate Change As global society confronts the challenges of diminishing resources, ecological degradation, and climate change, engineers play a crucial role designing and building technologies and products that fulfil our needs for utility and sustainability. The Handbook of Sustainable Engineering equips readers with the context and the best practices derived from both academic research and practical examples of successful implementations of sustainable technical solutions. The handbook’s content revolves around the two themes, new ways of thinking and new business models, including sustainable production, products, service systems and consumption while addressing key asse...

  4. COLOMBIAN MINING SUSTAINABILITY

    National Research Council Canada - National Science Library

    JORGE MARTÍN MOLINA ESCOBAR; OSCAR JAIME RESTREPO BAENA

    2010-01-01

    This is a brief reference to mining sustainability in Colombia. First, it discusses the concept of sustainability and its relationship to mineral resources, covering topics of ethical, economical and environmental issues...

  5. FORUM: Is Ecotourism Sustainable?

    Science.gov (United States)

    Wall

    1997-07-01

    / It is legitimate to ask whether and in what form tourism might contribute to sustainable development. This is not the same as sustainable tourism which, as a single-sector approach to development, may overlook important linkages with other sectors. If tourism is to contribute to sustainable development, then it must be economically viable, ecologically sensitive and culturally appropriate. Ecotourism is often advocated as being a sustainable form of tourism but imprecision in terminology clouds basic issues and there are strong economic, ecological, and cultural reasons for believing that, even in its purest forms, ecotourism is likely to present substantial challenges to destination areas, particularly if it competes for scarce resources and displaces existing uses and users. Sustainable tourism and ecotourism are not synonyms, many forms of ecotourism may not be sustainable, and if ecotourism is to contribute to sustainable development, then careful planning and management will be required.KEY WORDS: Ecotourism; Sustainable development; Development; Tourism

  6. Sustainable Public Bids

    Directory of Open Access Journals (Sweden)

    Gil César Costa de Paula

    2016-06-01

    Full Text Available In this article we will discuss the issue of sustainability in public procurement, given that the government in Brazil is constituted as a great promoter of economic development and needs to adapt its acquisitions worldwide sustainability agenda.

  7. Indicators for environmental sustainability

    DEFF Research Database (Denmark)

    Dong, Yan; Hauschild, Michael Zwicky

    2017-01-01

    Decision making on sustainable consumption and production requires scientifically based information on sustainability. Different environmental sustainability targets exist for specific decision problems. To observe how well these targets are met, relevant environmental indicators are needed....... In this study, we reviewed indicators applied in life cycle assessment (LCA), planetary boundary framework (PB), and Sustainable Development Goals (SDGs) developed under United Nation. The aim is to 1) identify their applications and relevant decision context; 2) Review their indicators and categorize them...

  8. Indicators for environmental sustainability

    DEFF Research Database (Denmark)

    Dong, Yan; Hauschild, Michael Zwicky

    2017-01-01

    Decision making on sustainable consumption and production requires scientifically based information on sustainability. Different environmental sustainability targets exist for specific decision problems. To observe how well these targets are met, relevant environmental indicators are needed....... In this study, we reviewed indicators applied in life cycle assessment (LCA), planetary boundary framework (PB), and Sustainable Development Goals (SDGs) developed under United Nation. The aim is to 1) identify their applications and relevant decision context; 2) Review their indicators and categorize them...

  9. Enterprise Sustainment Metrics

    Science.gov (United States)

    The Air Force sustainment enterprise does not have metrics that . . . adequately measure key sustainment parameters, according to the 2011 National...standardized and do not contribute to the overall assessment of the sustainment enterprise . This paper explores the development of a single metric...is not feasible. To answer the question does the sustainment enterprise provide cost-effective readiness for a weapon system, a suite of metrics is

  10. The Sustainable Development Model

    OpenAIRE

    2012-01-01

    Sustainable development concept approaches quality of life in complexity, as economic, social and environmental issues, promoting the idea of balance between economic development, social equity, efficient utilization and environment conservation.     An essential condition for achieving sustainable development is the right mix of macroeconomic policies coherent, consistent with resources to ensure sustainability of materials and energy used for growth.

  11. Sustainability: An Overview.

    Science.gov (United States)

    Wormsley, W. E.

    1990-01-01

    This article introduces a group of six papers on sustainability of programs for visually handicapped persons in developing countries. Sustainability is discussed from an anthropological perspective, noting the importance of a social soundness analysis and a social impact assessment, enemies of sustainability, and the need for broad local input in…

  12. Sustainability: An Overview.

    Science.gov (United States)

    Wormsley, W. E.

    1990-01-01

    This article introduces a group of six papers on sustainability of programs for visually handicapped persons in developing countries. Sustainability is discussed from an anthropological perspective, noting the importance of a social soundness analysis and a social impact assessment, enemies of sustainability, and the need for broad local input in…

  13. Education for sustainable development

    DEFF Research Database (Denmark)

    Breiting, Søren

    2009-01-01

     An introduction to the idea of sustainable development (SD) and education for sustainable development (ESD) with reference to the international Decade for Education for Sustainable Development . The chapter includes a focus on conflicting interests between present and future generations related...

  14. Measuring Educational Sustainability

    Science.gov (United States)

    Selvanathan, Rani G.

    2013-01-01

    There are many definitions that are attributable to the meaning of sustainability. Sustainability can be viewed as long-lasting, effective result of a project, venture, action, or investment without consuming additional future resources. Because of the wide nature of its applicability, a universal measure of sustainability is hard to come by. This…

  15. Sustainability Statement and Policy

    Science.gov (United States)

    Journal of Education for Sustainable Development, 2009

    2009-01-01

    This article presents nine resources that focus on environmental education and sustainability. These include: (1) "Sustainability Statement and Policy," Dalhousie University, Nova Scotia, Canada, 2009, which is available at http://office.sustainability.dal.ca/Governance; (2) "Climate Literacy: The Essential Principles of Climate…

  16. Sustainable Learning Organizations

    Science.gov (United States)

    Velazquez, Luis E.; Esquer, Javier; Munguia, Nora E.; Moure-Eraso, Rafael

    2011-01-01

    Purpose: The purpose of this paper is to debate how companies may better become a sustainable learning organization by offering the most used and insightful concepts of sustainability. Design/methodology/approach: Through literature review, learning organization and sustainability perspectives are explored and compared. Findings: Learning…

  17. Education for sustainable development

    DEFF Research Database (Denmark)

    Breiting, Søren

    2009-01-01

     An introduction to the idea of sustainable development (SD) and education for sustainable development (ESD) with reference to the international Decade for Education for Sustainable Development . The chapter includes a focus on conflicting interests between present and future generations related...

  18. Custodial Operations: Green & Sustainable

    Science.gov (United States)

    Campbell, J. Kirk

    2008-01-01

    Custodial Operations can have a significant impact on institutional green and sustainable goals if given the proper support and challenge. This article describes the green and sustainable custodial operations in place at Carleton College in Northfield, Minnesota. The article reviews the college's sustainable efforts on biodegradables, packaging,…

  19. Sustainable Learning Organizations

    Science.gov (United States)

    Velazquez, Luis E.; Esquer, Javier; Munguia, Nora E.; Moure-Eraso, Rafael

    2011-01-01

    Purpose: The purpose of this paper is to debate how companies may better become a sustainable learning organization by offering the most used and insightful concepts of sustainability. Design/methodology/approach: Through literature review, learning organization and sustainability perspectives are explored and compared. Findings: Learning…

  20. Sustainable Low Carbon Transport Scenarios for India

    DEFF Research Database (Denmark)

    Shukla, P.R.; Dhar, Subash; Mittal, Shivika

    2014-01-01

    and local air quality that can be accrued by mainstreaming climate change polices into national sustainable development goals and sectoral plans are also estimated. There is no silver bullet that would enable the transition towards low carbon transport. An optimal mix of policies that includes fuel economy...

  1. Modeling and Advanced Control for Sustainable Process Systems

    Science.gov (United States)

    This book chapter introduces a novel process systems engineering framework that integrates process control with sustainability assessment tools for the simultaneous evaluation and optimization of process operations. The implemented control strategy consists of a biologically-insp...

  2. Development of Chemical Process Design and Control for Sustainability

    Science.gov (United States)

    This contribution describes a novel process systems engineering framework that couples advanced control with sustainability evaluation and decision making for the optimization of process operations to minimize environmental impacts associated with products, materials, and energy....

  3. Striking the metapopulation balance : mathematical models & methods meet metapopulation management

    NARCIS (Netherlands)

    Etienne, R.S.

    2002-01-01

    There are two buzz words in nature management: fragmentation and connectivity. Not only (rail) roads, but also agricultural, residential and industrial areas fragment previously connected (or even continuous) habitat. Common sense tells us that the answer to habitat fragmentation is defragm

  4. Striking the metapopulation balance : Mathematical Models & Methods Meet Metapopulation Management

    NARCIS (Netherlands)

    Etienne, R.S.

    2002-01-01

    There are two buzz words in nature management: fragmentation and connectivity. Not only (rail) roads, but also agricultural, residential and industrial areas fragment previously connected (or even continuous) habitat. Common sense tells us that the answer to habitat fragmentation is defragmentation

  5. Sustainability in Business

    DEFF Research Database (Denmark)

    Tollin, Karin; Vej, Jesper

    2012-01-01

    How do companies integrate sustainability into their strategy and practices, and what factors explain their approach? In this paper a typology of sustainability strategies is presented as well as a conceptual framework relating sustainability at the company level to the functional level...... of marketing. The central contribution of the typology is a strategic and managerial view on sustainability. Furthermore, the typology shows that sustainability in business is enacted from different areas of competences and fields in the literature (e.g. supply chain management, corporate branding, value...... creation, product innovation and business model innovation). The empirical basis for the typology is an exploratory study of managers' mindsets about sustainability as strategy. Ten top managers involved with integrating sustainability within their companies have been interviewed. In order to reveal...

  6. Fur and Sustainability

    DEFF Research Database (Denmark)

    Skjold, Else; Csaba, Fabian

    2016-01-01

    This paper explores the notion of deeper luxury, which insists that 'real' luxury should involve sustainable practices in the production and consumption of luxury goods. It traces historical and recent developments in the field of fur, to understand the implications, uncertainties and ambiguities...... of luxury’s confrontation with sustainability. Considering fur in relation to future standards for luxury products, we raise questions about moral problematisation and justification of luxury in terms of sustainability. We first examine the encounter of luxury with sustainability and explain...... the significance of the notion of ‘deeper luxury’. After taking stock of the impact of sustainability on luxury and various directions in which sustainable luxury is evolving, we discuss concepts of sustainable development in relation to the history of moral problematisation of luxury. This leads to the case...

  7. Health and sustainability.

    Science.gov (United States)

    Kjӕrgård, Bente; Land, Birgit; Bransholm Pedersen, Kirsten

    2014-09-01

    In the present article, we explore how sustainable development strategies and health promotion strategies can be bridged. The concept of the 'duality of structure' is taken as our starting point for understanding the linkages between health promotion and sustainable development, and for uncovering the structural properties or conditions which either enable or constrain sustainable public health initiatives. We argue that strategies towards health promotion are not sufficiently integrated with strategies for sustainable development, and thus political strategies aimed at solving health problems or sustainability problems may cause new, undesired and unforeseen environmental or health problems. First, we explore how the relation between health and sustainability is articulated in international policy documents. Next, we develop a model for understanding the relation between health promotion and sustainability. Third, we use examples from agriculture and food production to illustrate that health and sustainability are mutually enabling and constraining. We conclude that while the renewed focus on food security and food inequalities has brought the health and sustainability dimensions of the food system onto the political agenda, the conceptualization of duality between health and sustainability could be a new platform for a critical and theoretical stance towards the market-oriented food system strategy. Thinking along the lines of duality means that the integration of health promotion strategies and sustainable development strategies cannot be based on an approach to integration in which either health or sustainability is given precedence over the other. From a duality perspective, integration means conceiving sustainability from a health perspective and health from a sustainability perspective. © The Author (2013). Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  8. Sustainable water resources management of Prokletije region

    Directory of Open Access Journals (Sweden)

    Svetlana M Stevovic

    2014-04-01

    Full Text Available The main goal of this paper is the upgrading of classic economic analyses of optimal concept selection of small hydro development. Techno-economic small hydro system needs to be environmentally friendly and socially acceptable solution. Environmental and social parameters are quantified by Delphi method. They are results of Environmental and Social impact assessment study of the project. Environmental and social parameters are incorporated in the techno-economic analyses for the optimal sustainable concept of small hydro development, by Elektra method, as possible multi attributive operational research model. System of small hydro power plants optimization for Prokletije streams catchments area is case study where the developed model is tested and proofed. Economic cost and total investment of fifteen possible small hydro power plants has been upgraded with quantified environmental and social parameters and analyzed in the function of sustainable economic development of Prokletije region.

  9. RELATIVITY AND SUSTAINABLE DEVELOPMENT

    Institute of Scientific and Technical Information of China (English)

    YE Dai-fu

    2004-01-01

    From the realism of science, and taking the guide of EINSTEIN's Relativity as guide, this article called in question the present theory of the sustainable development by the rational thinking of philosophy and a close logic inference. It is found that there are many paradoxes to the theory. Through more deepening and meticulous inference, we arrived at philosophic language of science about the sustainable development. The sustainable development is "non-sustainable development", and the non-sustainable development is "the best sustainable development''. While carrying out philosophical principle thinking and repeating science demonstration for the sustainable development, this article got further confirmation that the existence of human being at the minimum environment cost may help them obtain motive power of the sustainable development. In fact, this foundation motive power exists in the flow of development in different organization levels, meanwhile it exists in strategy of intuition living of the ancient people. Only in relative lower environment cost to live can we get the support system of science for the sustainable development, and be able really to achieve the basic goal of the sustainable development.

  10. [What is sustainability science?].

    Science.gov (United States)

    Wu, Jian-Guo; Guo, Xiao-Chuan; Yang, Jie; Qian, Gui-Xia; Niu, Jian-Ming; Liang, Cun-Zhu; Zhang, Qing; Li, Ang

    2014-01-01

    Sustainability is the theme of our time and also the grandest challenge to humanity. Since the 1970s, the term, sustainable development, has frequently appeared in the scientific literature, governmental documents, media promotions for public goods, and commercial advertisements. However, the science that provides the theoretical foundation and practical guidance for sustainable development--sustainability science--only began to emerge in the beginning of the 21st century. Nevertheless, the field has rapidly developed in depth and expanded in scope during the past decade, with its core concepts and research methods coalescing. China, as the most populous country in the world and home to the philosophical root of sustainability science-the unity of man and nature, is obligated to take upon the challenge of our time, to facilitate global sustainability while pursuing the Chinese Dream, and to play a leading role in the development of sustainability science. Toward this grandiose goal, this paper presents the first Chinese introduction to sustainability science, which discusses its basic concepts, research questions, and future directions. Sustainability science is the study of the dynamic relationship between humans and the environment, particularly focusing on the vulnerability, robustness, resilience, and stability of the coupled human-environment system. It is a transdisciplinary science that integrates natural sciences with humanities and social sciences. It hinges on the environment-economy-society nexus, and merges basic and applied research. The key components of sustainability often change with time, place, and culture, and thus sustainability science needs to emphasize multi-scale studies in space and time, with emphasis on landscapes and regions over a horizon of 50 to 100 years. It needs to focus on the relationship between ecosystem services and human well-being, as influenced by biodiversity and ecosystem processes as well as climate change, land use

  11. SMART SUSTAINABLE ISLANDS VS SMART SUSTAINABLE CITIES

    Directory of Open Access Journals (Sweden)

    D. N. Pantazis

    2017-09-01

    Full Text Available This paper has several aims: a the presentation of a critical analysis of the terms “smart sustainable cities” and “smart sustainable islands” b the presentation of a number of principles towards to the development methodological framework of concepts and actions, in a form of a manual and actions guide, for the smartification and sustainability of islands. This kind of master plan is divided in thematic sectors (key factors which concern the insular municipalities c the creation of an island’s smartification and sustainability index d the first steps towards the creation of a portal for the presentation of our smartification actions manual, together with relative resources, smart applications examples, and, in the near future the first results of our index application in a number of Greek islands and e the presentation of some proposals of possible actions towards their sustainable development and smartification for the municipalities - islands of Paros and Antiparos in Greece, as case studies.

  12. Health and Sustainability

    DEFF Research Database (Denmark)

    Land, Birgit; Pedersen, Kirsten Bransholm; Kjærgård, Bente

    2014-01-01

    In the present article, we explore how sustainable development strategies and health promotion strategies can be bridged. The concept of the ‘duality of structure’ is taken as our starting point for understanding the linkages between health promotion and sustainable development, and for uncovering...... the structural properties or conditions which either enable or constrain sustainable public health initiatives. We argue that strategies towards health promotion are not sufficiently integrated with strategies for sustainable development, and thus political strategies aimed at solving health problems...... or sustainability problems may cause new, undesired and unforeseen environmental or health problems. First, we explore how the relation between health and sustainability is articulated in international policy documents. Next, we develop a model for understanding the relation between health promotion...

  13. Measuring Corporate Sustainability Performance

    Directory of Open Access Journals (Sweden)

    Eugen Nicolăescu

    2015-01-01

    Full Text Available The aim of the present study is to examine and evaluate the evolving character of sustainability management in corporations, the significance of environmental protection and sustainability, and barriers to carrying out an incorporated and strategic firm-wide advance of social responsibility. In the present paper, we focus on the contribution of sustainability undertakings towards enhancing corporate performance, the financial involvements of sustainability position and operation, and the chief function of values in corporate policy. Our paper contributes to the literature by supplying proof of elements that lead to the triumph of business patterns for sustainable development, processes through which stakeholders are affecting corporate sustainability conduct, and the link between economic growth and the environment.

  14. Life Cycle Sustainability Dashboard

    DEFF Research Database (Denmark)

    Traverso, Marzia; Finkbeiner, Matthias; Jørgensen, Andreas

    2012-01-01

    One method to assess the sustainability performance of products is life cycle sustainability assessment (LCSA), which assesses product performance considering the environmental,economic, and social dimensions of the life cycle. The results of LCSA can be used to compare different products...... of sustainability is the communicability of the results by means of a graphical representation (a cartogram), characterized by a suitable chromatic scale and ranking score. The integration of LCSA and the dashboard of sustainability into a so-called Life Cycle Sustainability Dashboard (LCSD) is described here...... or to support decision making toward sustainable production and consumption. In both cases, LCSA results could be too disaggregated and consequently too difficult to understand and interpret by decision makers. As non-experts are usually the target audience of experts and scientists, and are also involved...

  15. Is Mass Customization Sustainable?

    DEFF Research Database (Denmark)

    Petersen, Thomas Ditlev; Jørgensen, Kaj Asbjørn; Nielsen, Kjeld

    2011-01-01

    Mass customizers are like other companies currently experiencing an increasing customer demand for environmentally sustainable products as well as an increasingly strict legislation regarding environmental sustainability. This paper addresses the issue whether the concepts mass customization...... and sustainability are fundamentally compatible by asking the question: can a mass customized product be sustainable? Several factors could indicate that mass customized products are less sustainable than standardized products; however other factors suggest the opposite. This paper explores these factors during...... three life cycle phases for a product: Production, Use and End of Life. It is concluded that there is not an unambiguous causal relationship between mass customization and sustainability; however several factors unique to mass customized products are essential to consider during product and process...

  16. Sustainability and Entrepreneurial Action

    DEFF Research Database (Denmark)

    Korsgaard, Steffen T.; Anderson, Alistair

    Abstract Objectives - This paper explores how entrepreneurial action can lead to environmental sustainability. It builds on the assumption that the creation of sustainble practices is one of the most important challenges facing the global society, and that entrepreneurial action is a vital...... instrument in the pursuit of sustainability.  Prior Work - Extant literature identifies two main approaches to sustainable entrepreneurship. (i) traditional exploitation of environmentally relevant opportunities and (ii) institutional entrepreneurship creating opportunities. We identify a novel form......: resource oriented sustainable entrepreneurial action.  Approach - The paper uses a case study approach to build deeper theoretical knowledge of environmentally sustainable entrepreneurship.  Results - The paper identifies and analyses a distinct form of sustainable entrepreneurship -  resource oriented...

  17. ICT innovations for sustainability

    CERN Document Server

    Aebischer, Bernard

    2015-01-01

    ICT Innovations for Sustainability is an investigation of how information and communication technology can contribute to sustainable development. It presents clear definitions of sustainability, suggesting conceptual frameworks for the positive and negative effects of ICT on sustainable development. It reviews methods of assessing the direct and indirect impact of ICT systems on energy and materials demand, and examines the results of such assessments. In addition, it investigates ICT-based approaches to supporting sustainable patterns of production and consumption, analyzing them at various levels of abstraction – from end-user devices, Internet infrastructure, user behavior, and social practices to macro-economic indicators.   Combining approaches from Computer Science, Information Systems, Human-Computer Interaction, Economics, and Environmental Sciences, the book presents a new, holistic perspective on ICT for Sustainability (ICT4S). It is an indispensable resource for anyone working in the area of ICT...

  18. Sustainable Concrete Technology

    Directory of Open Access Journals (Sweden)

    Sim J.

    2015-12-01

    Full Text Available The growing concern over global warming and significant ecological changes requires sustainable development in all fields of science and technology. Concrete not only consumes huge amount of energy and natural sources, but also emits large amount of CO2, mainly due to the production of cement. It is evident that such large amount of concrete production has put significant impact on the energy, resource, environment, and ecology of the society. Hence, how to develop the concrete technology in a sustainable way has become a significant issue. In this paper, some of Korean researches for sustainable development of concrete are presented. These are sustainable strengthening for deteriorated concrete structure, sustainable reinforcement of new concrete structure, sustainable concrete using recycled aggregate and supplementary cementing materials and finally application of each technique to precast concrete.

  19. IDB Biofuels Sustainability Scorecard

    OpenAIRE

    2009-01-01

    This document presents the IDB Biofuels Sustainability Scorecard user's guide. The primary objective of the Scorecard is to provide a tool to think through the complex issues associated with biofuels from the field to the tank, thereby encouraging higher levels of sustainability in such projects. While the Scorecard addresses many sustainability issues, it should not be used as a replacement for certification schemes and/or life-cycle assessment tools, but rather should inform these processes...

  20. Sustainable Agricultural Marketing Initiatives

    OpenAIRE

    Hakan Adanacıoğlu

    2015-01-01

    Sustainable marketing is a holistic approach that puts equal emphasis on environmental, social equity, and economic concerns in the development of marketing strategies. The purpose of the study is to examine and discuss the sustainable agricultural marketing initiatives practiced throughout the World and Turkey, and to put forth suggestions to further improve the performance of agricultural marketing initiatives in Turkey. Some of the sustainable agricultural marketing initiatives practiced a...

  1. Strategic Leadership towards Sustainability

    OpenAIRE

    Robèrt, Karl-Henrik; Broman, Göran; Waldron, David; Ny, Henrik; Byggeth, Sophie; Cook, David; Johansson, Lena; Oldmark, Jonas; Basile, George; Haraldsson, Hördur V.

    2004-01-01

    The Master's programme named "Strategic Leadership Towards Sustainability" is offered at the Blekinge Institute of Technology (Blekinge Tekniska Högskola) in Karlskrona, Sweden. This Master's programme builds on four central themes: (1) four scientific principles for socio-ecological sustainability; (2) a planning methodology of "backcasting" based on those scientific principles for sustainability; (3) a five-level model for planning in complex systems, into which backcasting is incorporated ...

  2. Sustainable fashion: New approaches

    OpenAIRE

    Niinimäki, Kirsi

    2013-01-01

    This publication is intended to be used as a source of inspiration for designers and companies, and all stakeholders whose interest lies in the area of sustainable fashion. While the strategies for sustainability are complex and approaches are many, this publication presents only a few ways to approach sustainable fashion. I hope the publication offers inspiration on how to make positive change in current practices and how to effect new mindsets, creating transformative fashion. Theoretica...

  3. Sustainable Housing Renewal

    OpenAIRE

    M. Sitar; K. Krajnc

    2008-01-01

    Following the already proved models the sustainable planning culture is endangering several methods directed towards the needs of tenants in the existing post-war housing stock. The case-study of our project is the renewal of the multi stored building in the housing estate Metalna, Maribor/Tezno (1949). It is based on the sustainable renovation principle for the quality of sustainable housing in functional, technological and environmental point of view. According to it, the idea of the projec...

  4. Characteristics of Digital Sustainability

    OpenAIRE

    Stuermer, Matthias

    2014-01-01

    The concept of digital sustainability is mentioned in research on digital preservation as well as on openness topics. Both streams of literature point out the necessary discussion how to create, use, and regulate digital resources in order to maximize their value for our society today and in the future. This paper therefore reviews current work on digital sustainability, presents a list of six charac-teristics how to define digitally sustainable goods, and draws the link to aspects of e-gover...

  5. Implementing Sustainable Development Strategies

    Institute of Scientific and Technical Information of China (English)

    Zhang Cuiying

    2004-01-01

    China's national sustainable development strategies were drafted under the guidance of Deng Xiaoping's theory on socialist construction with Chinese distinguishing features and, the theory and practice of sustainable development has further enriched and perfected Deng Xiaoping's theory. An in-depth study of Deng Xiaoping's theory is significant if we are to accurately understand our sustainable development program and how to best implement the strategies.

  6. Energy Security, Innovation & Sustainability Initiative

    Energy Technology Data Exchange (ETDEWEB)

    None

    2010-04-30

    's National Laboratories, that can provide real-world improvements in both the short- and long-term. Indeed, the roles of government and the private sector in energy sustainability were brought into sharper focus by the pending American Recovery and Reinvestment Act of 2009, also known as the economic stimulus bill. There was cautious optimism that the bill was moving the nation in the right direction by way of focusing on greater energy efficiency, alternative forms of energy and improved infrastructure. Nevertheless, there was concern over Congress picking energy winners and losers. Instead, Congress should challenge industry to produce solutions that will create a clear path forward to energy sustainability that the American people can support.

  7. Predicting Sustainable Work Behavior

    DEFF Research Database (Denmark)

    Hald, Kim Sundtoft

    2013-01-01

    Sustainable work behavior is an important issue for operations managers – it has implications for most outcomes of OM. This research explores the antecedents of sustainable work behavior. It revisits and extends the sociotechnical model developed by Brown et al. (2000) on predicting safe behavior....... Employee characteristics and general attitudes towards safety and work condition are included in the extended model. A survey was handed out to 654 employees in Chinese factories. This research contributes by demonstrating how employee- characteristics and general attitudes towards safety and work...... condition influence their sustainable work behavior. A new definition of sustainable work behavior is proposed....

  8. Sustainability assessment and complementarity

    Directory of Open Access Journals (Sweden)

    Hugo F. Alrøe

    2016-03-01

    Full Text Available Sustainability assessments bring together different perspectives that pertain to sustainability to produce overall assessments, and a wealth of approaches and tools have been developed in the past decades. However, two major problems remain. The problem of integration concerns the surplus of possibilities for integration; different tools produce different assessments. The problem of implementation concerns the barrier between assessment and transformation; assessments do not lead to the expected changes in practice. We aim to analyze issues of complementarity in sustainability assessment and transformation as a key to better handling the problems of integration and implementation. Based on a generalization of Niels Bohr's complementarity from quantum mechanics, we have identified two forms of complementarity in sustainability assessment, observer stance complementarity and value complementarity. Unlike many other problems of sustainability assessment, complementarity is of a fundamental character connected to the very conditions for observation. Therefore, complementarity cannot be overcome methodologically, only handled better or worse. Science is essential to the societal goal of sustainability, but these issues of complementarity impede the constructive role of science in the transition to more sustainable structures and practices in food systems. The agencies of sustainability assessment and transformation need to be acutely aware of the importance of different perspectives and values and the complementarities that may be connected to these differences. An improved understanding of complementarity can help to better recognize and handle issues of complementarity. These deliberations have relevance not only for sustainability assessment, but more generally for transdisciplinary research on wicked problems.

  9. Sustainable wireless networks

    CERN Document Server

    Zheng, Zhongming; Xuemin

    2013-01-01

    This brief focuses on network planning and resource allocation by jointly considering cost and energy sustainability in wireless networks with sustainable energy. The characteristics of green energy and investigating existing energy-efficient green approaches for wireless networks with sustainable energy is covered in the first part of this brief. The book then addresses the random availability and capacity of the energy supply. The authors explore how to maximize the energy sustainability of the network and minimize the failure probability that the mesh access points (APs) could deplete their

  10. Action Research for Sustainability

    DEFF Research Database (Denmark)

    Egmose, Jonas

    by analysing processes of social learning. The book addresses the need to move towards sustainability at societal level as a democratic challenge questioning the way we live on planet earth. By conceptualising sustain-ability as an immanent and emergent ability of ecological and social life, continuously...... to provide local citizens with a greater say in the future of urban sustainability research, this book shows how action research can make important methodological contributions to processes of social learning between citizens and scientists by enabling free spaces in peoples everyday life and within academia...

  11. Action Research for Sustainability

    DEFF Research Database (Denmark)

    Egmose, Jonas

    on urban sustainability the need to move towards sustainability at societal level is conceptualised as a democratic challenge questioning the way we live on planet earth. By understanding sustainability as an immanent and emergent ability of ecological and social life, continuously to renew itself without...... with a greater say in the future of urban sustainability research, the work shows how action research can make important methodological contributions to processes of social learning between citizens and scientists by enabling free spaces in peoples everyday life and within academia, where aspects...

  12. iSustainable

    OpenAIRE

    Domènech Aguilera, Roger

    2011-01-01

    El projecte iSustainable conjuga el desenvolupament i investigació en la tecnologia iPhone d'Apple amb un projecte ja existent dins de l'empresa Solvay anomenat Solvay Sustainable. Està enfocat a càrrecs directius de la companyia, els quals necessiten consultar les dades proporcionades per l'aplicació en tot moment. El proyecto iSustainable conjuga el desarrollo e investigación en la tecnología iPhone de Apple con un proyecto ya existente en la empresa Solvay llamado Solvay Sustainable. Es...

  13. Business ethics and sustainability

    African Journals Online (AJOL)

    fundamental issues about obligations to shareholders. DISCUSSION PAPER. Business ... Keywords: business ethics, managing ethical practice, morality, sustainable hospitality ..... are facing increasing pressure on their natural, cultural and.

  14. BUILDING ENVELOPE OPTIMIZATION USING EMERGY ANALYSIS

    Science.gov (United States)

    Energy analysis is an integral component of sustainable building practices. Energy analysis coupled with optimization techniques may offer solutions for greater energy efficiency over the lifetime of the building. However, all such computationsemploy the energy used for operation...

  15. Environmental indicators for industrial optimization and design

    NARCIS (Netherlands)

    Konneman, Bram

    2008-01-01

    Companies use standard financial indicators to determine their business success and optimize their business opportunities. However, sustainable development demands for an integrated approach to economic, environmental and social indicators. Although a lot of indicator initiatives are under

  16. Environmental indicators for industrial optimization and design

    NARCIS (Netherlands)

    Konneman, Bram

    2008-01-01

    Companies use standard financial indicators to determine their business success and optimize their business opportunities. However, sustainable development demands for an integrated approach to economic, environmental and social indicators. Although a lot of indicator initiatives are under developme

  17. Environmental indicators for industrial optimization and design

    NARCIS (Netherlands)

    Konneman, Bram

    2008-01-01

    Companies use standard financial indicators to determine their business success and optimize their business opportunities. However, sustainable development demands for an integrated approach to economic, environmental and social indicators. Although a lot of indicator initiatives are under developme

  18. Reduction of losses in industrial driving systems: the Brazilian Program focusing the self sustainable (Optimization of industrial driving systems); Reducao de perdas em sistemas motrizes industriais: a estrutura do Programa Brasileiro com foco na autosustentabilidade (Otimizacao de sistema motrizes industriais)

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Vanda Alves dos [ELETROBRAS - Centrais Eletricas Brasileiras, Rio de Janeiro, RJ (Brazil). Procel Industria]. E-mail: vandaas@eletrobras.com; Soares, George Alves [ELETROBRAS - Centrais Eletricas Brasileiras, Rio de Janeiro, RJ (Brazil). Desenvolvimento de Projetos Especiais (DPE)]. E-mail: georgesoares@eletrobras.com; Perrone, Fernando Pinto Dias [ELETROBRAS - Centrais Eletricas Brasileiras, Rio de Janeiro, RJ (Brazil). Div. de Projetos Setoriais de Eficiencia Energetica (DPEE); Ferreira, Carlos Aparecido; Oliveira, Humberto Luiz de; Motta, Braulio Romano

    2006-07-01

    This work presents basically the goals and the results obtained the expected by the Industrial Energy Efficiency Program - PROCEL Industria, relative to his Driving Systems Optimization Project. So, the main target of the project is to minimize the losses in the driving systems already installed in the brazilian industry and to promote the utilization of high yield motors in new applications, considering their relevance under the energy and cost viewpoint.

  19. The Potential of IT for Corporate Sustainability

    Directory of Open Access Journals (Sweden)

    Stefan Hack

    2014-07-01

    Full Text Available Several studies have proven that information technology (IT can improve enterprises’ performance. The effective and efficient management of enterprise resources has for long been the role of enterprise resource planning (ERP systems. Whereas traditional ERP systems focused on the optimization of financial resources and assets, the manifold challenges of a sustainable development necessitate broadening that view. Business applications need to provide informational transparency on all kinds of financial, environmental and social indicators, both within the enterprise and along the value chain; they need to support business processes and enable the measuring, tracking and reporting of sustainability performance, as well as the compliance with legal regulations, all implying substantial potential for improving corporate sustainability. However, the understanding of the potential of IT for corporate sustainability poses an interesting and valuable research topic. Drawing on previous works of Luftman, Melville et al. and Dao et al., we propose a conceptual model for the sustainability value of IT. We will summarize the main aspects of the recent discussion around the capabilities of IT and, then, illustrate with best-practice examples how these capabilities can be utilized for improved sustainability performance in a corporate setting. The paper concentrates on the second order effects of IT, like process improvements or substitution effects, which have also been described as “green through IT”.

  20. Sustainability for the Americas Initiative: Land Design Institute, Ball State University

    Science.gov (United States)

    J. L. Motloch; Pedro Pacheco; Eloy F. Jr. Casagrande

    2006-01-01

    The Ball State University Land Design Institute (LDI) pursues ecologically and culturally sustainable land design through education, research, outreach, and demonstration. LDI seeks to lead communities (local, regional, global) to sustainable futures. It connects communities and sustainability experts to optimize education about land management, planning, and design...

  1. Engineering Students' Sustainability Approaches

    Science.gov (United States)

    Haase, S.

    2014-01-01

    Sustainability issues are increasingly important in engineering work all over the world. This article explores systematic differences in self-assessed competencies, interests, importance, engagement and practices of newly enrolled engineering students in Denmark in relation to environmental and non-environmental sustainability issues. The…

  2. Engineering Students' Sustainability Approaches

    Science.gov (United States)

    Haase, S.

    2014-01-01

    Sustainability issues are increasingly important in engineering work all over the world. This article explores systematic differences in self-assessed competencies, interests, importance, engagement and practices of newly enrolled engineering students in Denmark in relation to environmental and non-environmental sustainability issues. The…

  3. Sustainable development and law

    NARCIS (Netherlands)

    Peeters, M.G.W.M.; Schomerus, Th.; Heinrichs, H.; Martens, P.; Michelsen, G.; WIek, A.

    2016-01-01

    Since the emergence of the concept of sustainable development, lawyers across the globe are trying to come to grips with its legal status and the potential legal consequences. Nowadays, the concept of sustainable development is represented in legally binding texts at international, European, and nat

  4. Sustainability of prevention.

    Science.gov (United States)

    Swisher, J D; Clayton, R

    2000-01-01

    This paper outlines the guidelines for sustaining prevention and makes suggestions for getting from the field's current status to greater levels of permanence for prevention. The paper begins by reviewing the status of prevention, then focuses on major considerations for achieving sustainability, including two processes of institutionalization, comprehensive programming and professionalism.

  5. Sustainable Supply Chain Design

    DEFF Research Database (Denmark)

    Bals, Lydia; Tate, Wendy

    design for TBL sustainability. These are located in catastrophe-ridden Haiti and supported by the Germany-based investor company Yunus Social Business. Three supply chain archetypes combining physical and support chains are presented that focus on TBL sustainable outputs and outcomes. For SSCM research...

  6. Sustainability as Moral Action

    Science.gov (United States)

    Dunn, Merrily S.; Hart-Steffes, Jeanne S.

    2012-01-01

    When one considers sustainability as a moral action, there are equally complex realities at hand--climate change, resource depletion, water and land rights. One author describes this broad sense of sustainability as "the connection of specific social and environmental problems to the functioning of human and ecological systems" (Jenkins, 2011).…

  7. Aesthetics of sustainable architecture

    NARCIS (Netherlands)

    Lee, S.

    2011-01-01

    The purpose of this book is to reveal, explore and further the debate on the aesthetic potentials of sustainable architecture and its practice. This book opens a new area of scholarship and discourse in the design and production of sustainable architecture, one that is based in aesthetics. The chapt

  8. Framing questions of sustainability

    NARCIS (Netherlands)

    Read, S.A.

    2014-01-01

    Sustainability sits at the top of the policy agendas of the EU and other governmental bodies. But sustainability is complex and not one thing, it relates to different sectors and multiple systems, and also to different zones, scales, ‘levels’ those systems occupy. Theoretically and practically we

  9. Framing questions of sustainability

    NARCIS (Netherlands)

    Read, S.A.

    2014-01-01

    Sustainability sits at the top of the policy agendas of the EU and other governmental bodies. But sustainability is complex and not one thing, it relates to different sectors and multiple systems, and also to different zones, scales, ‘levels’ those systems occupy. Theoretically and practically we ar

  10. Aesthetics of sustainable architecture

    NARCIS (Netherlands)

    Lee, S.

    2011-01-01

    The purpose of this book is to reveal, explore and further the debate on the aesthetic potentials of sustainable architecture and its practice. This book opens a new area of scholarship and discourse in the design and production of sustainable architecture, one that is based in aesthetics. The chapt

  11. Leading Sustainability in Schools

    Science.gov (United States)

    Carr, Katie

    2016-01-01

    What is the role of schools, and more specifically school leadership, in the transition to a sustainable future for humankind? What different forms of leadership are needed to enable this role? The challenges are huge and complex and for those of us engaged in promoting sustainability learning, it is clear that the issue has never been more…

  12. Sustainability of abrasive processes

    DEFF Research Database (Denmark)

    Aurich, J.C.; Linke, B.; Hauschild, Michael Zwicky

    2013-01-01

    , the content of technical presentations in STC G, and the results of a comprehensive literature study. The approach to sustainability includes environmental, social, and economic sustainability in accordance with the definition proposed in the Brundtland Report of the United Nations [156]. The main focus...

  13. Lean maturity, lean sustainability

    DEFF Research Database (Denmark)

    Jørgensen, Frances; Matthiesen, Rikke; Nielsen, Jacob

    2007-01-01

    Although lean is rapidly growing in popularity, its implementation is far from problem free and companies may experience difficulties sustaining long term success. In this paper, it is suggested that sustainable lean requires attention to both performance improvement and capability development. A...

  14. Sustainable grass farming

    OpenAIRE

    Leach, Katharine; Smith, Jo; Padel, Susanne

    2013-01-01

    Sustainable grassland farming” suggests a stable, productive system, with limited dependence on external inputs, which is economically viable. Effects on the wider environment, particularly air, water and wildlife, also need to be considered. Many principles contribute o sustainability, this article concentrate on two of them: “healthy soil” and “plant species diversity”.

  15. Sustainability at BPA 2012

    Energy Technology Data Exchange (ETDEWEB)

    None

    2012-12-01

    BPA’s Sustainability Action Plan is grounded in our commitment to environmental stewardship and Executive Order 13514 that calls on the federal agencies to “lead by example” by setting a 2020 greenhouse gas emissions target, increasing energy efficiency; reducing fleet petroleum consumption; conserving water; reducing waste; supporting sustainable communities; and leveraging federal purchasing power to promoting environmentally responsible products and technologies.

  16. Sustainable built environments

    CERN Document Server

    Haase, Dagmar

    2013-01-01

    Sustainable design is a collective process whereby the built environment achieves unprecedented levels of ecological balance through new and retrofit construction, with the goal of long-term viability and humanization of architecture. Focusing on the environmental context, sustainable design merges the natural, minimum resource conditioning solutions of the past (daylight, solar heat, and natural ventilation) with the innovative technologies of the present.  The desired result is an integrated “intelligent” system that supports individual control with expert negotiation for resource consciousness. International experts in the field address the fundamental questions of sustainable design and landscape management: How should the sustainability of landscapes and buildings be evaluated? Which targets have to be set and which thresholds should not be exceeded? What forms of planning and governance structures exist and to what extent do they further the goals of sustainability?  Gathering 30 peer-reviewed ent...

  17. Sustainability Marketing Commitment

    DEFF Research Database (Denmark)

    Tollin, Karin; Bech Christensen, Lars

    2017-01-01

    Corporate sustainability is an important strategy and value orientation for marketing, but scarce research addresses the organizational drivers and barriers to including it in companies’ marketing strategies and processes. The purpose of this study is to determine levels of commitment to corporate...... sustainability in marketing, processes associated with sustainability marketing commitment, drivers of sustainability marketing at the functional level of marketing, and its organizational context. Using survey data from 269 managers in marketing, covering a broad range of industries in Sweden and Denmark, we...... took a structural modelling approach to examine construct relationships, mediation, and moderation effects. Overall, the findings show that marketing capabilities associated with the innovation of new products, services, and business models constitute a strong driver to leverage sustainability...

  18. Sustainability and Organizational Change

    Directory of Open Access Journals (Sweden)

    Catălina Sitnikov

    2012-06-01

    Full Text Available The relevant and, above all, remarkable feature of sustainability is due to its "duality": on the one hand, it is an indispensable element within the companies even if, on the other hand, it increases the costs of many activities and processes. Facing the challenge of sustainability will determine and create, in the coming years, emerging organizational forms. If ten years ago, many managers clearly expressed their doubts regarding the financial feasibility of sustainability, today, they admit the importance of sustainability for the competitive advantage of the companies they manage. Currently, companies have great opportunities to support build a sustainable global economy, becoming one of the solutions to the most pressing societal challenges. Whether it is about reducing pollution, global warming, reducing use of water resources and other limited resources or ensuring a better work environment for employees throughout the supply chain, there are many things that companies can and should do.

  19. Fur and sustainability

    DEFF Research Database (Denmark)

    Skjold, Else; Ræbild, Ulla; Tanderup, Sisse

    2016-01-01

    interviews and observations at the premises of Kopenhagen Fur, as well as with stakeholders and collaborate partners in Denmark and in China. The definition of sustainability in the report must be seen as related to Design School Kolding's research umbrella of Sustainable Futures - a term chosen to unite...... of operationalizing shared memory in relation to issues of fur and sustainability (by Sisse Tanderup, PhD in art history) • a perspective on material processing that point towards ways of promoting and communicating best practices of i.e. dressing and dying of raw skin (by Karen Marie Hasling, PhD in textile...... engineering) • a perspective on design processes within the fur sector that point towards traditional and potentially future practices for designing more sustainably (by Ulla Ræbild, PhD in design research) • a perspective on user experiences of fur garment that point towards potentials for more sustainable...

  20. Agroecology and Sustainable Agriculture

    Directory of Open Access Journals (Sweden)

    Fabio Caporali

    Full Text Available In the framework of the 16th National Meeting of the Italian Ecological Society (“Global Change, Ecological Diversity and Sustainability”, University of Tuscia, Viterbo, 19-22 September 2006, a symposium was devoted to “Agroecology and Sustainable Development”. A major goal of this symposium was to contribute to keeping the dialogue among the experts of the various disciplines alive. Sustainability of agriculture is a challenge for society world wide. Universities and society as a whole have a responsibility in re-examining current perception of nature, of the world and of human society in the light of natural resources depletion, increasing pollution and social inequalities. The urgency to address sustainability issues is increasingly being reflected in the manner in which institutions of higher education around the world are giving priority to the teaching, research and practice of sustainability. The University of Tuscia is involved in international initiatives concerning teaching and research in Agroecology and Sustainable Agriculture.

  1. Agroecology and Sustainable Agriculture

    Directory of Open Access Journals (Sweden)

    Fabio Caporali

    2011-02-01

    Full Text Available In the framework of the 16th National Meeting of the Italian Ecological Society (“Global Change, Ecological Diversity and Sustainability”, University of Tuscia, Viterbo, 19-22 September 2006, a symposium was devoted to “Agroecology and Sustainable Development”. A major goal of this symposium was to contribute to keeping the dialogue among the experts of the various disciplines alive. Sustainability of agriculture is a challenge for society world wide. Universities and society as a whole have a responsibility in re-examining current perception of nature, of the world and of human society in the light of natural resources depletion, increasing pollution and social inequalities. The urgency to address sustainability issues is increasingly being reflected in the manner in which institutions of higher education around the world are giving priority to the teaching, research and practice of sustainability. The University of Tuscia is involved in international initiatives concerning teaching and research in Agroecology and Sustainable Agriculture.

  2. The sustainability solutions agenda.

    Science.gov (United States)

    Sarewitz, Daniel; Clapp, Richard; Crumbley, Cathy; Kriebel, David; Tickner, Joel

    2012-01-01

    Progress toward a more sustainable society is usually described in a "knowledge-first" framework, where science characterizes a problem in terms of its causes and mechanisms as a basis for subsequent action. Here we present a different approach-A Sustainability Solutions Agenda (SSA)-which seeks from the outset to identify the possible pathways to solutions. SSA focuses on uncovering paths to sustainability by improving current technological practice, and applying existing knowledge to identify and evaluate technological alternatives. SSA allows people and organizations to transition toward greater sustainability without sacrificing essential technological functions, and therefore does not threaten the interests that depend on those functions. Whereas knowledge-first approaches view scientific information as sufficient to convince people to take the right actions, even if those actions are perceived as against their immediate interests, SSA allows values to evolve toward greater attention to sustainability as a result of the positive experience of solving a problem.

  3. optimal control

    Directory of Open Access Journals (Sweden)

    L. I. Rozonoer

    1999-01-01

    Full Text Available Necessary and sufficient conditions for existence of optimal control for all initial data are proved for LQ-optimization problem. If these conditions are fulfilled, necessary and sufficient conditions of optimality are formulated. Basing on the results, some general hypotheses on optimal control in terms of Pontryagin's maximum condition and Bellman's equation are proposed.

  4. Sustained User Engagement in Health Information Technology: The Long Road from Implementation to System Optimization of Computerized Physician Order Entry and Clinical Decision Support Systems for Prescribing in Hospitals in England.

    Science.gov (United States)

    Cresswell, Kathrin M; Lee, Lisa; Mozaffar, Hajar; Williams, Robin; Sheikh, Aziz

    2016-10-07

    To explore and understand approaches to user engagement through investigating the range of ways in which health care workers and organizations accommodated the introduction of computerized physician order entry (CPOE) and computerized decision support (CDS) for hospital prescribing. Six hospitals in England, United Kingdom. Qualitative case study. We undertook qualitative semi-structured interviews, non-participant observations of meetings and system use, and collected organizational documents over three time periods from six hospitals. Thematic analysis was initially undertaken within individual cases, followed by cross-case comparisons. We conducted 173 interviews, conducted 24 observations, and collected 17 documents between 2011 and 2015. We found that perceived individual and safety benefits among different user groups tended to facilitate engagement in some, while other less engaged groups developed resistance and unsanctioned workarounds if systems were perceived to be inadequate. We identified both the opportunity and need for sustained engagement across user groups around system enhancement (e.g., through customizing software) and the development of user competencies and effective use. There is an urgent need to move away from an episodic view of engagement focused on the preimplementation phase, to more continuous holistic attempts to engage with and respond to end-users. © Health Research and Educational Trust.

  5. Sustainable winegrowing: current perspectives

    Directory of Open Access Journals (Sweden)

    Mariani A

    2015-05-01

    Full Text Available Angela Mariani,1 Antonella Vastola2 1Department of Economic and Legal Studies, University Parthenope, Naples, 2School of Agricultural, Forestry, Food and Environmental Sciences, University of Basilicata, Potenza, Italy Abstract: The winegrowing sector worldwide is strongly committed to improving environmental and social sustainability. The aim of this work, based on a literature review, is to highlight current sustainability perspectives and the related main issues. There is a broad consensus that the challenge to achieve a greater spread of sustainable practices is to enhance environmental and social sustainability while maintaining economic viability. From the producers' point of view, the priority is to bridge the still substantial knowledge gaps in terms of perceived environmental benefits, economic benefits, and costs. Thus, an increased research effort focusing on the costs and benefits of different winegrowing practices and technical assistance with implementation might support their diffusion. Moreover, targeted marketing strategies are needed to: enhance consumers' involvement and their attitude toward sustainable wine; improve understanding and use of sustainable labels and claims; and raise awareness of some environmental credentials of wine packaging, mainly with reference to lightweight glass bottles. Keywords: winegrower, sustainability, wine, consumer, marketing strategies

  6. Interpreting sustainable development

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    Over the past decade, the term" sustainable development"has emerged as the principal concept in the development field. The concept emerged in the 1970s and was first promoted in the international environmental and development communities with the publication of the " world conservation strategy"(1980). It was popularized by the Brundtland report, " Our common future"(1987). The Brundtland Commission defined sustainable development as " development which meets the needs of the present, without compromising the sustainability of future generation to meet their own needs". The Earth Summit(1992) established "sustainable development" as the most important policy of the 21st century. Since then, the relationship between development and environment has been widely discussed and sustainabale development is now an important part of the vocabulary of environmental policy research and analysis. In this paper, we begin by tracing the evolution of the concept of sustainable development. Definitions of sustainable development in ecology, economics and sociology are then explored and discussed. This paper also examine the contribution that a broadly-based concept of sustainable development can make: as a goal, an attitude and as a guiding principle for integrating economic development and environmental protection.

  7. Sustainability Infused Curriculum

    Science.gov (United States)

    Ibarra, D. L.

    2015-12-01

    The Independent Schools Foundation Academy (ISF) in Hong Kong established a sustainability policy in 2015, which explicitly states, "an experimentally integrated, environmentally and ethically sustainable system of science education and conservation practices based on the 2012 Jeju Declaration of the World Conservation Congress will be implemented through the school". ISF Academy is a private Chinese bilingual school in Hong Kong serving over 1500 students K-12, following the framework and curriculum of the International Baccalaureate Organization (IBO). The strategy behind the implementation of this policy includes: development of a scientific sustainable curriculum that is age appropriate; establish a culture of sustainability within the ISF community and beyond to the wider HK community; install sustainable infrastructure that allows students to learn; and learn first hand sustainable living practices. It is well understood that solutions to the environmental challenges facing Hong Kong and our planet will require multiple disciplines. The current sustainability programs at ISF include: a) a whole school aerobic food waste composting system and organic farming, b) energy consumption monitoring of existing buildings, c) upcoming installation of an air pollution monitoring equipment that will correlate with the AQHI data collected by the Hong Kong government, d) a Renewable Energy Education Center (REEC) that will teach students about RE and also produce solar energy for classroom consumption, and e) student lead environmental group that manages the paper and used cooking oil recycling on campus. The Shuyuan Science and Sustainability faculty work closely with classroom teachers to ensure that the above mentioned projects are incorporated into the curriculum throughout the school. Interdisciplinary units (IDU) of study are being developed that encourage faculty and students to work across subject areas. Projects include Personal Projects, Extended Essays

  8. Integrating Sustainability in Organisations: An Activity-Based Sustainability Model

    National Research Council Canada - National Science Library

    Ana Rodríguez-Olalla; Carmen Aviles-Palacios

    2017-01-01

    .... Although global integration models address sustainability in organisations, these models present shortcomings and limitations and do not describe how to achieve the integration of sustainability...

  9. Green and Sustainable Chemistry

    Institute of Scientific and Technical Information of China (English)

    HAN Boxing

    2011-01-01

    @@ It is now a common opinion that sustainable development is a key issue to humanity.How to provide the population with sufficient clean water, food, chemicals, materials and energy without damaging our planet is an extremely important and challenging issue in today's world.Although the chemical industry plays a pivotal role in driving the world economy and sustaining the high quality of life, most currently used chemical processes are not sustainable because they use fossil resources as their feedstock and produce a large amount of waste and hazardous materials.

  10. Sustainability & Organization Design

    DEFF Research Database (Denmark)

    Rasmussen, Morten Bygvraa; Obel, Børge; Kallehave, Pernille

    of global governance to match the new dynamics and consequences of globalization. Governments are re-examining corporate accountability to society and how companies earn their license to operate. Furthermore companies are re-examining their code of conduct and leadership values. Thus, sustainability...... is an important driver in organizations and its impact and effect on organization design is critical. Development of organization design, structure, processes, and human skills and values are needed to create the sustainable organization for the future. This paper discusses the requirements to be a sustainable...

  11. Strategic corporate sustainability

    DEFF Research Database (Denmark)

    Grewatsch, Sylvia; Rohrbeck, René; Madsen, Henning

    This paper aims to advance the understanding of the circumstances under which corporate sustainability (CS) pays off. On the basis of a review of 129 major papers from both the sustainability and general management literature, we discuss the development of the research field. In addition we discuss...... antecedents and outcomes. To overcome this limitation we propose an integrated typology which may facilitate more research on the link between corporate sustainability performance (CSP) and corporate financial performance (CFP). Our expectation is that the strategy type might play a moderating or mediating...

  12. Sustainable Facilities Management

    DEFF Research Database (Denmark)

    Nielsen, Susanne Balslev; Elle, Morten; Hoffmann, Birgitte

    2004-01-01

    The Danish public housing sector has more than 20 years of experience with sustainable facilities management based on user involvement. The paper outlines this development in a historical perspective and gives an analysis of different approaches to sustainable facilities management. The focus...... is on the housing departments and strateies for the management of the use of resources. The research methods used are case studies based on interviews in addition to literature studies. The paper explores lessons to be learned about sustainable facilities management in general, and points to a need for new...

  13. Lean maturity, lean sustainability

    DEFF Research Database (Denmark)

    Jørgensen, Frances; Matthiesen, Rikke; Nielsen, Jacob

    2007-01-01

    Although lean is rapidly growing in popularity, its implementation is far from problem free and companies may experience difficulties sustaining long term success. In this paper, it is suggested that sustainable lean requires attention to both performance improvement and capability development....... A framework for describing levels of lean capability is presented, based on a brief review of the literature and experiences from 12 Danish companies currently implementing lean. Although still in its emerging phase, the framework contributes to both theory and practice by describing developmental stages...... that support lean capability development and consequently, lean sustainability....

  14. Innovation for Sustainable Tourism

    DEFF Research Database (Denmark)

    Carlsen, Jack; Edwards, D; Forde, P

    and making the transformation toward sustainability through innovation. This book assembles ten case studies of large and small enterprises and destinations in developed and developing nations that are pursuing innovative practices that will enhance the sustainability of their operations. The chapters......, but in other economic sectors as well. Being an online publication, it is expected that updates in successive editions of this first book will add further to the description and analysis of innovation for sustainable tourism and hence provide a resource for those seeking to enhance the teaching, research...

  15. Sustaining Participatory Design Initiatives

    DEFF Research Database (Denmark)

    Iversen, Ole Sejer; Dindler, Christian

    2014-01-01

    While many participatory design (PD) projects succeed in establishing new organisational initiatives or creating technology that is attuned to the people affected, the issue of how such results are sustained after the project ends remains an important challenge. We explore the challenge...... these various forms of sustainability may be pursued in PD practice and how they can become a resource in reflecting on PD activities. Finally, we discuss implications for PD practice, suggesting that a nuanced conception of sustainability and how it may relate to PD practice are useful resources for designers...... and researchers before, during and after design processes. View full text Download full text...

  16. Product engineering and sustainability

    Science.gov (United States)

    Janssen, L. P. B. M.; Janssen, C. H. C.

    2016-11-01

    Chemical engineering has made a substantial contribution to the improvement of the environment during the last decades. Many processes have become more sustainable and harmful waste streams are minimised. However, considerable improvement of sustainability can still be obtained in product engineering and design. Especially the aspects that are important at the end of the life cycle of the product can be improved considerably. A priority list for the design of more sustainable products is presented and illustrated with examples of daily chemical engineering practice.

  17. Strategic corporate sustainability

    DEFF Research Database (Denmark)

    Grewatsch, Sylvia; Rohrbeck, René; Madsen, Henning

    This paper aims to advance the understanding of the circumstances under which corporate sustainability (CS) pays off. On the basis of a review of 129 major papers from both the sustainability and general management literature, we discuss the development of the research field. In addition we discuss...... antecedents and outcomes. To overcome this limitation we propose an integrated typology which may facilitate more research on the link between corporate sustainability performance (CSP) and corporate financial performance (CFP). Our expectation is that the strategy type might play a moderating or mediating...

  18. Textiles and clothing sustainability nanotextiles and sustainability

    CERN Document Server

    2017-01-01

    This book highlights the sustainability aspects of textiles and clothing sector in light of nanomaterials and technologies. The invasion of nano in every industrial sector has been important and has made remarkable changes as well as posed new challenges, including the textiles and clothing sector. There is quite a great deal of research happening in terms of nano materials for textiles across the globe, some of which are covered in this book. .

  19. Sustainable or non-sustainable future?

    OpenAIRE

    Zbyněk Kuna

    2000-01-01

    Author mentions global problems of the world. Sustainable development and natural resources in relations to world population problem and food problem. He gives main responsibility for the future development to the developed countries and to the international institutions. Pieces of knowledge mentioned in the article result from the solution of the institutional research intention MSM 411100013 “Efficient integration of the Czech agrarian sector in the frame of the European structures - a pres...

  20. Using Bayesian Population Viability Analysis to Define Relevant Conservation Objectives.

    Directory of Open Access Journals (Sweden)

    Adam W Green

    Full Text Available Adaptive management provides a useful framework for managing natural resources in the face of uncertainty. An important component of adaptive management is identifying clear, measurable conservation objectives that reflect the desired outcomes of stakeholders. A common objective is to have a sustainable population, or metapopulation, but it can be difficult to quantify a threshold above which such a population is likely to persist. We performed a Bayesian metapopulation viability analysis (BMPVA using a dynamic occupancy model to quantify the characteristics of two wood frog (Lithobates sylvatica metapopulations resulting in sustainable populations, and we demonstrate how the results could be used to define meaningful objectives that serve as the basis of adaptive management. We explored scenarios involving metapopulations with different numbers of patches (pools using estimates of breeding occurrence and successful metamorphosis from two study areas to estimate the probability of quasi-extinction and calculate the proportion of vernal pools producing metamorphs. Our results suggest that ≥50 pools are required to ensure long-term persistence with approximately 16% of pools producing metamorphs in stable metapopulations. We demonstrate one way to incorporate the BMPVA results into a utility function that balances the trade-offs between ecological and financial objectives, which can be used in an adaptive management framework to make optimal, transparent decisions. Our approach provides a framework for using a standard method (i.e., PVA and available information to inform a formal decision process to determine optimal and timely management policies.

  1. Development of Chemical Process Design and Control for Sustainability

    Directory of Open Access Journals (Sweden)

    Shuyun Li

    2016-07-01

    Full Text Available This contribution describes a novel process systems engineering framework that couples advanced control with sustainability evaluation for the optimization of process operations to minimize environmental impacts associated with products, materials and energy. The implemented control strategy combines a biologically-inspired method with optimal control concepts for finding more sustainable operating trajectories. The sustainability assessment of process operating points is carried out by using the U.S. EPA’s Gauging Reaction Effectiveness for the ENvironmental Sustainability of Chemistries with a multi-Objective Process Evaluator (GREENSCOPE tool that provides scores for the selected indicators in the economic, material efficiency, environmental and energy areas. The indicator scores describe process performance on a sustainability measurement scale, effectively determining which operating point is more sustainable if there are more than several steady states for one specific product manufacturing. Through comparisons between a representative benchmark and the optimal steady states obtained through the implementation of the proposed controller, a systematic decision can be made in terms of whether the implementation of the controller is moving the process towards a more sustainable operation. The effectiveness of the proposed framework is illustrated through a case study of a continuous fermentation process for fuel production, whose material and energy time variation models are characterized by multiple steady states and oscillatory conditions.

  2. 生境破坏的空间结构对集合种群续存的影响%Influences of Habitat Destruction with Spatially Structure on Metapopulation Persistence

    Institute of Scientific and Technical Information of China (English)

    吴诗宝; 惠苍

    2008-01-01

    Habitat destruction is one of the most important desiderate problemin ecology, and researches always focus on the influences of destruction quantity, that is the fraction of destroyed habitat, on species' persistence, in which the most importantresult is the Levins rule and the minimum amount of suitable habitat (MASH). The im-portance of spatial structure of habitat destruction is scarcely concerned. In this paper,we first introduce the pair approximation into the study of metapopulation, ubstitutingfor the mean-field approximation. And then, we fully discuss the size, spatial structureand distribution of metapopulation induced by habitat destruction with spatial struc-ture. The results show that with the increases of destroyed fraction, the metapopulationsizes will decrease and distribute far away from the destroyed habitat, the clusteringstructure of metapopulation will collapses. With the decreases of destroyed clusteringdegree, the metapopulation will atrophy and the clustering structure will break down,and the metapopulation will increases and then disappears near the destroyed habitat.According to these esults, we can analyze the edge effect: it is not the fraction of habi-tat destruction but the boundary length of destroyed habitat that can depict the fullinfluences of habitat destruction. With the edge effect, we cursorily suggest that the re-maining habitat under destruction should prior to half of the origin to protect the speciesagainst extinction in a connective habitat. And the species living in patchy habitat willhave more resistance to habitat destruction than those residing in continuous habitat.%生境破坏及其影响是生态学亟待解决的问题之一,目前的研究主要集中在破坏数量,即遭破坏生境的比例,对物种续存的影响方面;其中最主要的结论是Levins原理和适合生境斑块最小数量(MASH),而关于生境破坏的空间结构的研究却比较稀少,在本文中,我们首先将偶对近似引入到

  3. QUEST for sustainable CPD

    DEFF Research Database (Denmark)

    Nielsen, Birgitte Lund

    2014-01-01

    phase. The findings are discussed looking forward to the institutionalization phase identifying factors potentially supporting sustainable development pertaining to local science teachers developing a shared focus on student learning in science, and perceived individual and collective efficacy...

  4. Sustainable Practices Innovation

    Science.gov (United States)

    Better sustainability means more environmentally conscious and efficient businesses and communities. EPA helps modify the way we consume energy, deal with waste, and grow our economy through programs such as Energy Star, E3, Smart Growth, and WaterSense.

  5. Sustainable Materials Management

    Science.gov (United States)

    To introduce businesses, NGOs, and government officials to the concept of Sustainable Materials Management (SMM). To provide tools to allow stakeholders to take a lifecycle approach managing their materials, & to encourage them to join a SMM challenge.

  6. Packaging for Sustainability

    CERN Document Server

    Lewis, Helen; Fitzpatrick, Leanne

    2012-01-01

    The packaging industry is under pressure from regulators, customers and other stakeholders to improve packaging’s sustainability by reducing its environmental and societal impacts. This is a considerable challenge because of the complex interactions between products and their packaging, and the many roles that packaging plays in the supply chain. Packaging for Sustainability is a concise and readable handbook for practitioners who are trying to implement sustainability strategies for packaging. Industry case studies are used throughout the book to illustrate possible applications and scenarios. Packaging for Sustainability draws on the expertise of researchers and industry practitioners to provide information on business benefits, environmental issues and priorities, environmental evaluation tools, design for environment, marketing strategies, and challenges for the future.

  7. Social Health and Sustainability

    DEFF Research Database (Denmark)

    Andersen, Heidi Lene

    2015-01-01

    Abstract: This article discusses how to accomplish a transition towards healthy and sustainable futures. Despite political statements and profound theoretical developments, little has happened in the field of practice. This article presents a number of problematics in the theoretical and conceptual...... development within the fields of sustainability and health promotion. With this objective in mind, this article seeks to find solutions to a question raised by the WHO health and sustainability researcher, Illona Kickbusch: ‘What conceptual framing and common language can help move a shared agenda forward...... departments. The article demonstrates that an action research approach including an Aristotelean phronetic perspective can be successful in integrating health and sustainability in research, as well as in practice. There are two main conclusions from the empirical case study. The first is that the common...

  8. Sustainable Enterprise Excellence

    DEFF Research Database (Denmark)

    Edgeman, Rick

    2013-01-01

    Structured Abstract Purpose: Sustainable Enterprise Excellence (SEE) is defined and developed through integration and expansion of business excellence modeling and sustainability thought. The intent is to enable simple yet reliable enterprise assessment of triple bottom line (TBL) performance...... and produce actionable enterprise foresight that can enable next best practices and sources of sustainable competitive advantage through innovation. Methodology: Key elements of SEE are identified from various business excellence and sustainability reporting sources, including the Global Reporting Initiative......, the UN Global Compact 10 Principles, and criteria of the European Quality Award and America’s Baldrige National Quality Award. From these a model and key criteria are distilled, maturity scales developed, and a simple means of assessment presented. Findings: A compact model and supporting maturity...

  9. Sovereignty, individuality, and sustainability

    Directory of Open Access Journals (Sweden)

    John Cairns Jr.

    2003-09-01

    Full Text Available Humans must acknowledge that the biosphere is the essential support for all living organisms. In order to achieve sustainable use of the planet, humans must proceed beyond egocentrism, ethnocentrism, homocentrism, and biocentrism to ecocentrism. National states, with present policies, are a major obstacle to sustainable use of the planet. However, there is some evidence that the individual has increasing sovereignty at the expense of both nation states and the environment. Still, the primary obstacle to sustainability is inherent in the present system of sovereign nation states. The basic question is how much sovereignty must nation-states and individuals relinquish to preserve the health of Earth's biospheric life support system. A free and open exchange of thoughts on this subject is long overdue. To acheive sustainable use of the planet, humankind must view its identity within the context of the interdependent web of life.

  10. Transport, environment and sustainability

    DEFF Research Database (Denmark)

    Joumard, Robert; Gudmundsson, Henrik; Kehagia, Fotini

    2010-01-01

    support tools are discussed. We define what "environmental sustainability in transport" may mean through the transport system, the concepts of sustainable development and of environment. The concept of 'chain of causality' between a source and a final target is developed, as a common reference...... as well as multi-criteria methods. Five case studies are presented. Finally, recommendations for continued research and development of indicators and joint considerations methods for assessment of environmental sustainability in transport are given.......This report is the final report of the action COST 356 'EST - Towards the definition of a measurable environmentally sustainable transport'. It tries to answer the following questions: How can environmental impacts of transport be measured? How can measurements be transformed into operational...

  11. Sustainable Buildings in Interaction

    DEFF Research Database (Denmark)

    Elle, Morten

    2007-01-01

    , and the focus on sustainable building have gradually turned from special houses on the countryside to normally looking houses in the urban fabric, integrated in the technical infrastructure. Some new built urban areas in Denmark will, however, not have to be supplied with district heating – these developments...... are going to consist of passive houses. The first sustainable buildings were built by their users, and the user – building interaction still play a decisive role for the performance of the present sustainable buildings. The users have to understand how the building functions. Urban design is essential......The first attempts to build sustainable buildings in Denmark were typically located on the countryside. The basic idea was to create buildings that were independent of the technical infrastructure. District heating has, however, been the dominating solution to heating in buildings in Denmark...

  12. The macroecology of sustainability

    Science.gov (United States)

    Burger, Joseph R.; Allen, Craig D.; Brown, James H.; Burnside, William R.; Davidson, Ana D.; Fristoe, Trevor S.; Hamilton, Marcus J.; Mercado-Silva, Norman; Nekola, Jeffrey C.; Okie, Jordan G.; Zuo, Wenyun

    2012-01-01

    The discipline of sustainability science has emerged in response to concerns of natural and social scientists, policymakers, and lay people about whether the Earth can continue to support human population growth and economic prosperity. Yet, sustainability science has developed largely independently from and with little reference to key ecological principles that govern life on Earth. A macroecological perspective highlights three principles that should be integral to sustainability science: 1) physical conservation laws govern the flows of energy and materials between human systems and the environment, 2) smaller systems are connected by these flows to larger systems in which they are embedded, and 3) global constraints ultimately limit flows at smaller scales. Over the past few decades, decreasing per capita rates of consumption of petroleum, phosphate, agricultural land, fresh water, fish, and wood indicate that the growing human population has surpassed the capacity of the Earth to supply enough of these essential resources to sustain even the current population and level of socioeconomic development.

  13. Sustainable Enterprise Excellence

    DEFF Research Database (Denmark)

    Edgeman, Rick; Williams, Joseph; Eskildsen, Jacob Kjær

    Sustainable Enterprise Excellence balances complementary and competing interests of key stakeholder segments, including society and the natural environment and increases the likelihood of superior and sustainable competitive positioning and hence long-term enterprise success that is defined......, supply chain, customer-related, human capital, financial, marketplace, societal, and environmental performance. Sustainable Enterprise Excellence integrates ethical, efficient and effective (E3) enterprise governance with 3E (equity, ecology, economy) Triple Top Line strategy throughout enterprise...... culture and activities to produce Triple Bottom Line 3P (people, planet, profit) performance that are simultaneously pragmatic, innovative and supportive of R3 (Edgeman, 2013). Sustainable Enterprise Excellence (Edgeman & Eskildsen, 2013) or SEE is analogous to Business & Performance Excellence. The role...

  14. Sustainable advanced construction technologies

    CSIR Research Space (South Africa)

    Kuchena, JC

    2009-11-01

    Full Text Available Advanced Construction Technologies (ACTs) are set to become the sustainable mainstay of the construction industry due to the demand for innovative housing solutions. Like most emerging economies, South Africa from a historical perspective and global...

  15. Business ethics and sustainability

    African Journals Online (AJOL)

    Introduction. Any discussion of sustainable business practice needs to be ... It may be that organisation leaders .... self-centred, others would argue that human history has more ..... relatively small compared to transport energy consumption,.

  16. Education for Sustainable development

    African Journals Online (AJOL)

    Southern African Journal of Environmental Education, Vol. ... are therefore also matters of concern in higher education, as this article discusses in more detail. .... The USAT forms part of a range of international sustainability-assessment tools ...

  17. Design for Sustainable Learning.

    Science.gov (United States)

    Christopher, Gaylaird

    2002-01-01

    Asserts that the greatest benefit to the design of green sustainable schools is the opportunity to provide meaningful, ecological learning experiences for children. Offers examples of learning opportunities within the environment and a list of related resources. (EV)

  18. The macroecology of sustainability.

    Science.gov (United States)

    Burger, Joseph R; Allen, Craig D; Brown, James H; Burnside, William R; Davidson, Ana D; Fristoe, Trevor S; Hamilton, Marcus J; Mercado-Silva, Norman; Nekola, Jeffrey C; Okie, Jordan G; Zuo, Wenyun

    2012-01-01

    The discipline of sustainability science has emerged in response to concerns of natural and social scientists, policymakers, and lay people about whether the Earth can continue to support human population growth and economic prosperity. Yet, sustainability science has developed largely independently from and with little reference to key ecological principles that govern life on Earth. A macroecological perspective highlights three principles that should be integral to sustainability science: 1) physical conservation laws govern the flows of energy and materials between human systems and the environment, 2) smaller systems are connected by these flows to larger systems in which they are embedded, and 3) global constraints ultimately limit flows at smaller scales. Over the past few decades, decreasing per capita rates of consumption of petroleum, phosphate, agricultural land, fresh water, fish, and wood indicate that the growing human population has surpassed the capacity of the Earth to supply enough of these essential resources to sustain even the current population and level of socioeconomic development.

  19. Sustainable Buildings in Interaction

    DEFF Research Database (Denmark)

    Elle, Morten

    2007-01-01

    The first attempts to build sustainable buildings in Denmark were typically located on the countryside. The basic idea was to create buildings that were independent of the technical infrastructure. District heating has, however, been the dominating solution to heating in buildings in Denmark......, and the focus on sustainable building have gradually turned from special houses on the countryside to normally looking houses in the urban fabric, integrated in the technical infrastructure. Some new built urban areas in Denmark will, however, not have to be supplied with district heating – these developments...... are going to consist of passive houses. The first sustainable buildings were built by their users, and the user – building interaction still play a decisive role for the performance of the present sustainable buildings. The users have to understand how the building functions. Urban design is essential...

  20. Wrapping Our Brains around Sustainability

    Directory of Open Access Journals (Sweden)

    Mary Ann Curran

    2009-03-01

    Full Text Available As many of us begin to embrace the concept of sustainability, we realize that it is not simply something that we ‘do.’ Rather, sustainability is a destination that we aspire to reach with the selection of the sustainable pathways that we choose as we proceed along the journey. We are embarking on a new journey with the creation of Sustainability, an on-line, open access journal. As stated on the journal’s website, Sustainability is an international and cross-disciplinary scholarly journal of environmental, cultural, economic and social sustainability of human beings, which provides an advanced forum for studies that are related to sustainability and sustainable development. To genuinely wrap our brains around the impact that our actions have on the sustainability of our planet, we must first understand something of the big picture and have a firm grasp of the terminology. To help further clarify the elusive term ‘sustainability,’ without attempting to provide an exact definition, this paper outlines various, inter-related concepts and basic practices and approaches that are being used in the name of sustainability, including: traditional end-of-pipe control strategies, life cycle, environmental sustainability, urban sustainability, industrial ecology, business sustainability, sustainable supply chain systems, sustainability indicators and metrics, green chemistry and green engineering, design for the environment, sustainable buildings, eco-tourism, and renewable and sustainable energy and fuels.