WorldWideScience

Sample records for network resource availability

  1. Available Resources for Reconfigurable Systems in 5G Networks

    DEFF Research Database (Denmark)

    Rodríguez Páez, Juan Sebastián; Vegas Olmos, Juan José

    2017-01-01

    In this paper, the concept of a Radio-over-Fiber based Centralized Radio Access Network is explained and analyzed, in order to identify a set of resources within the network that can be used as a base in the design of reconfigurable systems. This analysis is then used to design a different reconf...

  2. Optimizing available network resources to address questions in environmental biogeochemistry

    Science.gov (United States)

    Hinckley, Eve-Lyn; Suzanne Andersen,; Baron, Jill S.; Peter Blanken,; Gordon Bonan,; William Bowman,; Sarah Elmendorf,; Fierer, Noah; Andrew Fox,; Keli Goodman,; Katherine Jones,; Danica Lombardozzi,; Claire Lunch,; Jason Neff,; Michael SanClements,; Katherine Suding,; Will Wieder,

    2016-01-01

    An increasing number of network observatories have been established globally to collect long-term biogeochemical data at multiple spatial and temporal scales. Although many outstanding questions in biogeochemistry would benefit from network science, the ability of the earth- and environmental-sciences community to conduct synthesis studies within and across networks is limited and seldom done satisfactorily. We identify the ideal characteristics of networks, common problems with using data, and key improvements to strengthen intra- and internetwork compatibility. We suggest that targeted improvements to existing networks should include promoting standardization in data collection, developing incentives to promote rapid data release to the public, and increasing the ability of investigators to conduct their own studies across sites. Internetwork efforts should include identifying a standard measurement suite—we propose profiles of plant canopy and soil properties—and an online, searchable data portal that connects network, investigator-led, and citizen-science projects.

  3. Amino Acid Flux from Metabolic Network Benefits Protein Translation: the Role of Resource Availability.

    Science.gov (United States)

    Hu, Xiao-Pan; Yang, Yi; Ma, Bin-Guang

    2015-06-09

    Protein translation is a central step in gene expression and affected by many factors such as codon usage bias, mRNA folding energy and tRNA abundance. Despite intensive previous studies, how metabolic amino acid supply correlates with protein translation efficiency remains unknown. In this work, we estimated the amino acid flux from metabolic network for each protein in Escherichia coli and Saccharomyces cerevisiae by using Flux Balance Analysis. Integrated with the mRNA expression level, protein abundance and ribosome profiling data, we provided a detailed description of the role of amino acid supply in protein translation. Our results showed that amino acid supply positively correlates with translation efficiency and ribosome density. Moreover, with the rank-based regression model, we found that metabolic amino acid supply facilitates ribosome utilization. Based on the fact that the ribosome density change of well-amino-acid-supplied genes is smaller than poorly-amino-acid-supply genes under amino acid starvation, we reached the conclusion that amino acid supply may buffer ribosome density change against amino acid starvation and benefit maintaining a relatively stable translation environment. Our work provided new insights into the connection between metabolic amino acid supply and protein translation process by revealing a new regulation strategy that is dependent on resource availability.

  4. Sharing network resources

    CERN Document Server

    Parekh, Abhay

    2014-01-01

    Resource Allocation lies at the heart of network control. In the early days of the Internet the scarcest resource was bandwidth, but as the network has evolved to become an essential utility in the lives of billions, the nature of the resource allocation problem has changed. This book attempts to describe the facets of resource allocation that are most relevant to modern networks. It is targeted at graduate students and researchers who have an introductory background in networking and who desire to internalize core concepts before designing new protocols and applications. We start from the fun

  5. Fossil energy resources and availability

    Energy Technology Data Exchange (ETDEWEB)

    Wellmer, F.W. [Bundesanstalt fuer Geowissenschaften und Rohstoffkunde, Hannover (Germany); Barthel, F.; Hiller, K.

    2000-07-01

    World-wide consumption of hydrocarbons, coal and uranium presently amounts to about 13 Gt coal equivalent (tce) or c. 9 Gt oil equivalent (toe). According to predictions of the World Energy Council in 1998 world energy consumption will increase to around 17 to 19 Gtce in 2050. The present demand is meet to c. 45% by crude oil, c. 27% by coal, c. 21% by natural gas, and c. 7% by nuclear fuel. It is assumed that in the future the global consumption pattern will not change in principle, however regional variations may evolve. Especially renewable energy may increase its share from its present low percentage and the future role of nuclear power may decrease in certain areas. Assuming a 'business as usual' scenario of the global energy consumption demand for crude oil would increase from presently c. 3.8 Gtoe annually to c. 5 Gtoe in 2010 and possibly to 6 Gtoe in 2020. Global coal consumption is expected to rise from 3.3 Gtce to c. 4 Gtce in 2010 and natural gas from 2.3 G m{sup 3} to around 4 G m{sup 3} in the said period. The future contribution of nuclear power is uncertain due to low public acceptance in several countries. Therefore uranium demand may increase from presently 61,500 tU annually to 73,000 tU in 2010 or may decrease to about 60,000 tU. The present and future availability of the individual energy resources will be examined. (orig.)

  6. Networking Resource Centre

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 14; Issue 9. Networking Resource Centre. Information and Announcements Volume 14 Issue 9 September 2009 pp 930-930. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/014/09/0930-0930. Resonance ...

  7. High Availability in Optical Networks

    Science.gov (United States)

    Grover, Wayne D.; Wosinska, Lena; Fumagalli, Andrea

    2005-09-01

    Call for Papers: High Availability in Optical Networks Submission Deadline: 1 January 2006 The Journal of Optical Networking (JON) is soliciting papers for a feature Issue pertaining to all aspects of reliable components and systems for optical networks and concepts, techniques, and experience leading to high availability of services provided by optical networks. Most nations now recognize that telecommunications in all its forms -- including voice, Internet, video, and so on -- are "critical infrastructure" for the society, commerce, government, and education. Yet all these services and applications are almost completely dependent on optical networks for their realization. "Always on" or apparently unbreakable communications connectivity is the expectation from most users and for some services is the actual requirement as well. Achieving the desired level of availability of services, and doing so with some elegance and efficiency, is a meritorious goal for current researchers. This requires development and use of high-reliability components and subsystems, but also concepts for active reconfiguration and capacity planning leading to high availability of service through unseen fast-acting survivability mechanisms. The feature issue is also intended to reflect some of the most important current directions and objectives in optical networking research, which include the aspects of integrated design and operation of multilevel survivability and realization of multiple Quality-of-Protection service classes. Dynamic survivable service provisioning, or batch re-provisioning is an important current theme, as well as methods that achieve high availability at far less investment in spare capacity than required by brute force service path duplication or 100% redundant rings, which is still the surprisingly prevalent practice. Papers of several types are envisioned in the feature issue, including outlook and forecasting types of treatments, optimization and analysis, new

  8. Prostate Cancer Pathology Resource Network

    Science.gov (United States)

    2015-12-01

    AD_________________ Award Number: W81XWH-10-2-0056 TITLE: Prostate Cancer Pathology Resource Network PRINCIPAL INVESTIGATOR: Bruce J. Trock, Ph.D... Pathology Resource Network 5a. CONTRACT NUMBER 5b. GRANT NUMBER W81XWH-10-2-0056 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Bruce J. Trock, Ph.D. Betty...The Prostate Cancer Pathology Resource Network (which has since been renamed the Prostate Cancer Biorepository Network or PCBN) is a collaboration

  9. Strategic Management of Network Resources

    DEFF Research Database (Denmark)

    Antero, Michelle; Riis, Philip Holst

    2011-01-01

    This paper applies the resource-based view (RBV) theory to a case study aimed at identifying the complementary resources among partners in the ERPCorp ecosystem of development and implementation of Enterprise Resource Planning (ERP) for small and medium enterprises (SMEs) in Denmark. The paper an...... that the strategy, if implemented successfully, maintains competitive advantage for the ERPCorp ecosystem through effectively combining resources and leveraging lock-in and network effects....

  10. Resource management in wireless networking

    CERN Document Server

    Cardei, Mihaela; Du, Ding-Zhu

    2005-01-01

    This is the first book that provides readers with a deep technical overview of recent advances in resource management for wireless networks at different layers of the protocol stack. The subject is explored in various wireless networks, such as ad hoc wireless networks, 3G/4G cellular, IEEE 802.11, and Bluetooth personal area networks.Survey chapters give an excellent introduction to key topics in resource management for wireless networks, while experts will be satisfied by the technical depth of the knowledge imparted in chapters exploring hot research topics.The subject area discussed in this book is very relevant today, considering the recent remarkable growth of wireless networking and the convergence of wireless personal communications, internet technologies and real-time multimedia.This volume is a very good companion for practitioners working on implementing solutions for multimedia and Quality of Service - sensitive applications over wireless networks.Written for:Researchers, faculty members, students...

  11. NATURAL RESOURCES AVAILABILITY IN A SUSTAINABLE ECONOMY

    Directory of Open Access Journals (Sweden)

    CĂTĂLINA BONCIU

    2013-05-01

    Full Text Available In the theoretical and practical approach of the economic life, appears more often the idea of sustainable economic development, of reconciliation between man and nature in attracting and using its resources without interfering in its natural movement and evolution. In this paper we are trying to bring to light the relation between the economic development and the mineral resources, in terms of achieving sustainable development. The place and role of natural factors in the market economy is revealed by bringing to the forefront a number of arguments that demonstrate their vital position in the sustainable growth and development.

  12. CERN HUMAN RESOURCES 2002 REPORT NOW AVAILABLE

    CERN Multimedia

    Human Resources Division

    2002-01-01

    A report on CERN Human Resources is published once every two years. The English version of the 2002 report is now available: on the Web in your divisional secretariat if you need a paper copy. The Human Resources 2002 report gives information on various subjects: general information on CERN's aim and the organization of its operations, results of the five-yearly review of financial and social conditions, an overview of members of personnel working at CERN, with breakdowns by a wide range of parameters, significant aspects in employment conditions. The report is intended, in the first instance, to inform people outside CERN. However, all staff members should be familiar with the most important facts and figures it contains. Think about publicizing it among your contacts outside the Laboratory! A French version will be ready in September. Human Resources Division Tel. 74108

  13. Natural resources - their cost and availability

    Energy Technology Data Exchange (ETDEWEB)

    Desrousseaux, J.

    1982-03-01

    This paper presents an economic and polemic investigation into the availability of non-renewable natural resources. The author shows that the evolution of mineral reserves follows complex mathematical laws once economic factors are brought into play. The author examines the impact of the increases in demand, the effect of the diminishing reserves and the problem of cost price and selling price; he then studies and criticizes the classic theory of the management of natural resources and puts forward a theory for the management of non-renewable resources in which he shows that the selling price must exceed the marginal production costs, the margin being an increasing exponential function of time. (4 refs.) (In French)

  14. Self-Regulated Inquiry with Networked Resources

    Directory of Open Access Journals (Sweden)

    John C. Nesbit

    2003-10-01

    Full Text Available Abstract. In the context of continued growth in the accessibility of information through the internet, recent advances in theories of self-regulated learning present an opportunity to reexamine how learners work with networked resources in constructivist approaches such as problem-based learning, project-based learning, and collaborative problem solving. We present a Resource Inquiry model consisting of five stages: (1 Set resource inquiry goals, (2 Plan for resource study, (3 Search and select resources, (4 Study and assess new knowledge, and (5 Critique and recommend resources. Our model informs designers of online tools about how to support learners' cognitive and metacognitive strategies when learning activities involve interacting with networked resources.

  15. ACARA - AVAILABILITY, COST AND RESOURCE ALLOCATION

    Science.gov (United States)

    Viterna, L. A.

    1994-01-01

    ACARA is a program for analyzing availability, lifecycle cost, and resource scheduling. It uses a statistical Monte Carlo method to simulate a system's capacity states as well as component failure and repair. Component failures are modelled using a combination of exponential and Weibull probability distributions. ACARA schedules component replacement to achieve optimum system performance. The scheduling will comply with any constraints on component production, resupply vehicle capacity, on-site spares, or crew manpower and equipment. ACARA is capable of many types of analyses and trade studies because of its integrated approach. It characterizes the system performance in terms of both state availability and equivalent availability (a weighted average of state availability). It can determine the probability of exceeding a capacity state to assess reliability and loss of load probability. It can also evaluate the effect of resource constraints on system availability and lifecycle cost. ACARA interprets the results of a simulation and displays tables and charts for: (1) performance, i.e., availability and reliability of capacity states, (2) frequency of failure and repair, (3) lifecycle cost, including hardware, transportation, and maintenance, and (4) usage of available resources, including mass, volume, and maintenance man-hours. ACARA incorporates a user-friendly, menu-driven interface with full screen data entry. It provides a file management system to store and retrieve input and output datasets for system simulation scenarios. ACARA is written in APL2 using the APL2 interpreter for IBM PC compatible systems running MS-DOS. Hardware requirements for the APL2 system include 640K of RAM, 2Mb of extended memory, and an 80386 or 80486 processor with an 80x87 math co-processor. A dot matrix printer is required if the user wishes to print a graph from a results table. A sample MS-DOS executable is provided on the distribution medium. The executable contains licensed

  16. Resource Management in Broadband Communication Networks

    DEFF Research Database (Denmark)

    Hansen, Mads Stenhuus

    2003-01-01

    This thesis - Resource Management in Broadband Communication Networks - deals with different ways of optimizing the available resources of data- or telecommunication networks. Especially topics like optimal routing, load balancing and fast recovery of routes in case of link failures are covered....... The first part gives a brief description of some of the existing protocols for routing and controlling resources, such as RSVP, OSPF, BGP, PNNI, etc. The remaining part concerns the following two fundamentally different approaches to resource management etc.: - Software agents - Simulated ants...... at developing a demonstration platform, where software agents handled virtually all aspects of controlling an ATM-based network. In the beginning of the part about simulated ants it is explained how scientists believe ants in nature find their way through the environment between their nest and food sources...

  17. Availability Issues in Wireless Visual Sensor Networks

    Science.gov (United States)

    Costa, Daniel G.; Silva, Ivanovitch; Guedes, Luiz Affonso; Vasques, Francisco; Portugal, Paulo

    2014-01-01

    Wireless visual sensor networks have been considered for a large set of monitoring applications related with surveillance, tracking and multipurpose visual monitoring. When sensors are deployed over a monitored field, permanent faults may happen during the network lifetime, reducing the monitoring quality or rendering parts or the entire network unavailable. In a different way from scalar sensor networks, camera-enabled sensors collect information following a directional sensing model, which changes the notions of vicinity and redundancy. Moreover, visual source nodes may have different relevancies for the applications, according to the monitoring requirements and cameras' poses. In this paper we discuss the most relevant availability issues related to wireless visual sensor networks, addressing availability evaluation and enhancement. Such discussions are valuable when designing, deploying and managing wireless visual sensor networks, bringing significant contributions to these networks. PMID:24526301

  18. New Campus Crime Prevention Resources Available

    Science.gov (United States)

    Campus Law Enforcement Journal, 2012

    2012-01-01

    The Campus Crime Prevention Committee has compiled a list of university and college crime prevention agencies and resources, which includes contact information, links to agency crime prevention web pages, and a list of resources they offer (i.e., brochures, guides, PowerPoint programs, videos, etc.) as well as a spreadsheet showing organizations…

  19. Survivable resource orchestration for optically interconnected data center networks.

    Science.gov (United States)

    Zhang, Qiong; She, Qingya; Zhu, Yi; Wang, Xi; Palacharla, Paparao; Sekiya, Motoyoshi

    2014-01-13

    We propose resource orchestration schemes in overlay networks enabled by optical network virtualization. Based on the information from underlying optical networks, our proposed schemes provision the fewest data centers to guarantee K-connect survivability, thus maintaining resource availability for cloud applications under any failure.

  20. Iterative Available Bandwidth Estimation for Mobile Transport Networks

    DEFF Research Database (Denmark)

    Ubeda Castellanos, Carlos; López Villa, Dimas; Teyeb, Oumer Mohammed

    2007-01-01

    Available bandwidth estimation has lately been proposed to be used for end-to-end resource management in existing and emerging mobile communication systems, whose transport networks could end up being the bottleneck rather than the air interface. Algorithms for admission control, handover...

  1. Allocating resources between network nodes for providing a network node function

    NARCIS (Netherlands)

    Strijkers, R.J.; Meulenhoff, P.J.

    2014-01-01

    The invention provides a method wherein a first network node advertises available resources that a second network node may use to offload network node functions transparently to the first network node. Examples of the first network node are a client device (e.g. PC, notebook, tablet, smart phone), a

  2. Water Availability and Management of Water Resources

    Science.gov (United States)

    One of the most pressing national and global issues is the availability of freshwater due to global climate change, energy scarcity issues and the increase in world population and accompanying economic growth. Estimates of water supplies and flows through the world's hydrologic c...

  3. Resource allocation in networks via coalitional games

    NARCIS (Netherlands)

    Shams, F.

    2016-01-01

    The main goal of this dissertation is to manage resource allocation in network engineering problems and to introduce efficient cooperative algorithms to obtain high performance, ensuring fairness and stability. Specifically, this dissertation introduces new approaches for resource allocation in

  4. Tritium resources available for fusion reactors

    Science.gov (United States)

    Kovari, M.; Coleman, M.; Cristescu, I.; Smith, R.

    2018-02-01

    The tritium required for ITER will be supplied from the CANDU production in Ontario, but while Ontario may be able to supply 8 kg for a DEMO fusion reactor in the mid-2050s, it will not be able to provide 10 kg at any realistic starting time. The tritium required to start DEMO will depend on advances in plasma fuelling efficiency, burnup fraction, and tritium processing technology. It is in theory possible to start up a fusion reactor with little or no tritium, but at an estimated cost of 2 billion per kilogram of tritium saved, it is not economically sensible. Some heavy water reactor tritium production scenarios with varying degrees of optimism are presented, with the assumption that only Canada, the Republic of Korea, and Romania make tritium available to the fusion community. Results for the tritium available for DEMO in 2055 range from zero to 30 kg. CANDU and similar heavy water reactors could in theory generate additional tritium in a number of ways: (a) adjuster rods containing lithium could be used, giving 0.13 kg per year per reactor; (b) a fuel bundle with a burnable absorber has been designed for CANDU reactors, which might be adapted for tritium production; (c) tritium production could be increased by 0.05 kg per year per reactor by doping the moderator with lithium-6. If a fusion reactor is started up around 2055, governments in Canada, Argentina, China, India, South Korea and Romania will have the opportunity in the years leading up to that to take appropriate steps: (a) build, refurbish or upgrade tritium extraction facilities; (b) extend the lives of heavy water reactors, or build new ones; (c) reduce tritium sales; (d) boost tritium production in the remaining heavy water reactors. All of the alternative production methods considered have serious economic and regulatory drawbacks, and the risk of diversion of tritium or lithium-6 would also be a major concern. There are likely to be serious problems with supplying tritium for future

  5. Extracellular enzyme kinetics scale with resource availability

    Science.gov (United States)

    Sinsabaugh, Robert L.; Belnap, Jayne; Findlay, Stuart G.; Follstad Shah, Jennifer J.; Hill, Brian H.; Kuehn, Kevin A.; Kuske, Cheryl; Litvak, Marcy E.; Martinez, Noelle G.; Moorhead, Daryl L.; Warnock, Daniel D.

    2014-01-01

    Microbial community metabolism relies on external digestion, mediated by extracellular enzymes that break down complex organic matter into molecules small enough for cells to assimilate. We analyzed the kinetics of 40 extracellular enzymes that mediate the degradation and assimilation of carbon, nitrogen and phosphorus by diverse aquatic and terrestrial microbial communities (1160 cases). Regression analyses were conducted by habitat (aquatic and terrestrial), enzyme class (hydrolases and oxidoreductases) and assay methodology (low affinity and high affinity substrates) to relate potential reaction rates to substrate availability. Across enzyme classes and habitats, the scaling relationships between apparent Vmax and apparent Km followed similar power laws with exponents of 0.44 to 0.67. These exponents, called elasticities, were not statistically distinct from a central value of 0.50, which occurs when the Km of an enzyme equals substrate concentration, a condition optimal for maintenance of steady state. We also conducted an ecosystem scale analysis of ten extracellular hydrolase activities in relation to soil and sediment organic carbon (2,000–5,000 cases/enzyme) that yielded elasticities near 1.0 (0.9 ± 0.2, n = 36). At the metabolomic scale, the elasticity of extracellular enzymatic reactions is the proportionality constant that connects the C:N:P stoichiometries of organic matter and ecoenzymatic activities. At the ecosystem scale, the elasticity of extracellular enzymatic reactions shows that organic matter ultimately limits effective enzyme binding sites. Our findings suggest that one mechanism by which microbial communities maintain homeostasis is regulating extracellular enzyme expression to optimize the short-term responsiveness of substrate acquisition. The analyses also show that, like elemental stoichiometry, the fundamental attributes of enzymatic reactions can be extrapolated from biochemical to community and ecosystem scales.

  6. Implementing Resource-aware Multicast Forwarding in Software Defined Networks

    DEFF Research Database (Denmark)

    Poderys, Justas; Sunny, Anjusha; Soler, José

    2018-01-01

    Dened Networks (SDN), all this information is available in a centralized entity - SDN network. This work proposes to utilize the SDN paradigm to perform network-resources aware multicast data routing in the SDN controller. In a prototype implementation, multicast data is routed using a modied Edmonds...

  7. Professional development and human resources management in networks

    Directory of Open Access Journals (Sweden)

    Evgeniy Rudnev

    2016-05-01

    Full Text Available Social networks occupy more places in development of people and organizations. Confidence in institutions and social networking are different and based on referentiality in Internet. For communication in network persons choose a different strategies and behavior in LinkedIn, resources of whom may be in different degree are interesting in Human Resources Management for organizations. Members of different social groups and cultures demonstrate some differences in interaction with Russian identity native. There are gender differences behavior in networks. Participating in groups need ethical behavior and norms in social networking for professional development and communication in future.

  8. Cognitive resource management for heterogeneous cellular networks

    CERN Document Server

    Liu, Yongkang

    2014-01-01

    This Springer Brief focuses on cognitive resource management in heterogeneous cellular networks (Het Net) with small cell deployment for the LTE-Advanced system. It introduces the Het Net features, presents practical approaches using cognitive radio technology in accommodating small cell data relay and optimizing resource allocation and examines the effectiveness of resource management among small cells given limited coordination bandwidth and wireless channel uncertainty. The authors introduce different network characteristics of small cell, investigate the mesh of small cell access points in

  9. Improving human resource capacity for road network preservation

    CSIR Research Space (South Africa)

    Nxumalo, M

    2010-10-01

    Full Text Available There is compelling evidence that a significant factor contributing to the poor condition of much of Africa's rural road network is inadequate human resource capacity. This shortage of professional skills in road engineering inhibits proper...

  10. Cognitive radio networks dynamic resource allocation schemes

    CERN Document Server

    Wang, Shaowei

    2014-01-01

    This SpringerBrief presents a survey of dynamic resource allocation schemes in Cognitive Radio (CR) Systems, focusing on the spectral-efficiency and energy-efficiency in wireless networks. It also introduces a variety of dynamic resource allocation schemes for CR networks and provides a concise introduction of the landscape of CR technology. The author covers in detail the dynamic resource allocation problem for the motivations and challenges in CR systems. The Spectral- and Energy-Efficient resource allocation schemes are comprehensively investigated, including new insights into the trade-off

  11. Networked Resources, Assessment and Collection Development

    Science.gov (United States)

    Samson, Sue; Derry, Sebastian; Eggleston, Holly

    2004-01-01

    This project provides a critical evaluation of networked resources as they relate to the library's collection development policy, identifies areas of the curriculum not well represented, establishes a reliable method of assessing usage across all resources, and develops a framework of quantitative data for collection development decision making.

  12. Robust resource allocation in future wireless networks

    CERN Document Server

    Parsaeefard, Saeedeh; Mokari, Nader

    2017-01-01

    This book presents state-of-the-art research on robust resource allocation in current and future wireless networks. The authors describe the nominal resource allocation problems in wireless networks and explain why introducing robustness in such networks is desirable. Then, depending on the objectives of the problem, namely maximizing the social utility or the per-user utility, cooperative or competitive approaches are explained and their corresponding robust problems are considered in detail. For each approach, the costs and benefits of robust schemes are discussed and the algorithms for reducing their costs and improving their benefits are presented. Considering the fact that such problems are inherently non-convex and intractable, a taxonomy of different relaxation techniques is presented, and applications of such techniques are shown via several examples throughout the book. Finally, the authors argue that resource allocation continues to be an important issue in future wireless networks, and propose spec...

  13. IP, ethernet and MPLS networks resource and fault management

    CERN Document Server

    Perez, André

    2013-01-01

    This book summarizes the key Quality of Service technologies deployed in telecommunications networks: Ethernet, IP, and MPLS. The QoS of the network is made up of two parts: fault and resource management. Network operation quality is among the functions to be fulfilled in order to offer QoS to the end user. It is characterized by four parameters: packet loss, delay, jitter or the variation of delay over time, and availability. Resource management employs mechanisms that enable the first three parameters to be guaranteed or optimized. Fault management aims to ensure continuity of service.

  14. Research and Application of Knowledge Resources Network for Product Innovation

    Directory of Open Access Journals (Sweden)

    Chuan Li

    2015-01-01

    Full Text Available In order to enhance the capabilities of knowledge service in product innovation design service platform, a method of acquiring knowledge resources supporting for product innovation from the Internet and providing knowledge active push is proposed. Through knowledge modeling for product innovation based on ontology, the integrated architecture of knowledge resources network is put forward. The technology for the acquisition of network knowledge resources based on focused crawler and web services is studied. Knowledge active push is provided for users by user behavior analysis and knowledge evaluation in order to improve users’ enthusiasm for participation in platform. Finally, an application example is illustrated to prove the effectiveness of the method.

  15. Availability and Utilization of Information Resources and Service by ...

    African Journals Online (AJOL)

    The results revealed that the availability of library resources was fairly adequate and the library was under-utilized. Though the library services were available, staff were occasionally satisfied. The paper recommends improvement in library budgetary allocation, more community sensitization on library services, urgent ...

  16. Resource Management in Tactical Military Networks

    Science.gov (United States)

    2006-12-01

    FGAN FORSCHUNGSINSTITUT FÜR KOMMUNIKATION , INFORMATIONSVERARBEITUNG UND ERGONOMIE KIEKOMMUNIKATION Resource Management in Tactical Military Networks...Martin Lies, Peter Sevenich, Christoph Karg, Christoph Barz Nr: 2 FGAN FORSCHUNGSINSTITUT FÜR KOMMUNIKATION , INFORMATIONSVERARBEITUNG UND ERGONOMIE...Communication with IPSec in Tunnelmode Nr: 3 FGAN FORSCHUNGSINSTITUT FÜR KOMMUNIKATION , INFORMATIONSVERARBEITUNG UND ERGONOMIE KIEKOMMUNIKATION IPSec in

  17. Economic Aspects of a Resource Discovery Network.

    Science.gov (United States)

    Halliday, Leah; Oppenheim, Charles

    2001-01-01

    Explores economic aspects of a resource discovery network (RDN) in the United Kingdom consisting of a center and eight sub-based hubs using Ithink Analyst, a modeling software package. Results suggest that with a combination of sponsorship and subscription income a RDN could succeed without grant funding within 10 years of its launch. (Author/LRW)

  18. Social Networking: A Collaborative Open Educational Resource

    Science.gov (United States)

    Toetenel, Lisette

    2014-01-01

    Studies undertaken since the introduction of Web 2.0 have focussed mainly on open educational resources (OERs) such as email, blogging and virtual learning environments. No consistent efforts have been undertaken to study the use of social networking sites as a tool for learning in the second language classroom. This study examined the use of…

  19. ICT availability, accessibility and resource sharing in the federal ...

    African Journals Online (AJOL)

    The study discusses the availability, usability and resource sharing co-operatives engaged by the Federal Polytechnic Libraries in South West geo-political zone in Nigeria. Questionnaires accompanied with site visits to the institutions were used for data collection and the Polytechnic Librarians were the respondents.

  20. Material resources availability, parent subject perception and school ...

    African Journals Online (AJOL)

    Students' poor performance in the Yoruba language is being considered a serious problem by researchers and education stakeholders. Despite their efforts, no appreciable improvement is noticeable for hardly are enough researches on the extent to which school material resources availability, parental subject perception ...

  1. Resources available for school based mental health services in ...

    African Journals Online (AJOL)

    Background: Childhood mental illnesses most times are detected earlier in schools than at homes as the schools provide enabling environment for early identification of children with problems. Objectives: To evaluate the resources available for school-based mental health services in Enugu urban and to determine the head ...

  2. Medical resources after nuclear war. Availability v need.

    Science.gov (United States)

    Abrams, H L

    1984-08-03

    In defining capacity to "survive" a massive nuclear exchange, it is important to assess the medical resources that will be available in the post-nuclear war world. Approximately 80% of these resources--hospital beds and personnel, blood, drugs, and medical supplies--will have been destroyed, since they are located in or near the densely populated areas that constitute primary targets of attack. Casualty estimates published by federal agencies, together with data from the Hiroshima-Nagasaki experience, suggest the numbers and types of injuries that will afflict the US population. With a probable 48,000 surviving physicians to treat 32 million casualties, there will be one physician for every 663 patients. Of the trauma and burn victims, approximately 55% will require hospitalization; this will mean 64 patients for each available hospital bed. Data from recent wars have been utilized to determine the trauma-related blood requirements in the post-nuclear war world. Of the 64 million units of whole blood needed, only 14,000 will be available. Other medical resources will be in equally short supply. This disparity between need and availability indicates the difficulty of developing a meaningful medical response for the surviving injured.

  3. Integrated resource management for Hybrid Optical Wireless (HOW) networks

    DEFF Research Database (Denmark)

    Yan, Ying; Yu, Hao; Wessing, Henrik

    2009-01-01

    Efficient utilization of available bandwidth over hybrid optical wireless networks is a critical issue, especially for multimedia applications with high data rates and stringent Quality of Service (QoS) requirements. In this paper, we propose an integrated resource management including an enhanced...... resource sharing scheme and an integrated admission control scheme for the hybrid optical wireless networks. It provides QoS guarantees for connections through both optical and wireless domain. Simulation results show that our proposed scheme improves QoS performances in terms of high throughput and low...

  4. Bandwidth Management in Resource Constrained Networks

    Science.gov (United States)

    2012-03-01

    Control Protocol/Internet Protocol UDP User Datagram Protocol URL Uniform Resource Locator VPN Virtual Private Networks VSAT Very Small Aperture...grave registration site in Thailand in response to the tsunami. Researchers leveraged their Very Small Aperture Terminal ( VSAT ) to create an Internet...accessible Internet access for the communities “for all early responders, victims’ families, and government (local and federal)” through the use of two VSATs

  5. Available Resources for Algal Biofuel Development in China

    Directory of Open Access Journals (Sweden)

    Li Chen

    2011-08-01

    Full Text Available Microalgal biofuel research in China has made noticeable progress, and algae cultivation for biofuel production is considered to be an important contribution to Greenhouse Gas (GHG mitigation and energy security. In this paper, the algal biofuel potentiality in China was reviewed from the points of view of algal biodiversity, algal culture collection, GHGs (especially CO2 mitigation, and the availability of the required sunlight, wastewater and land resources. The cultivation of microalgae utilizing power plants gas with large amounts of CO2 and wastewaters from urban households, industry and animal husbandry are suitable for large scale production in China. Land is hardly a limitation for algae cultivation.

  6. Resource management for energy and spectrum harvesting sensor networks

    CERN Document Server

    Zhang, Deyu; Zhou, Haibo; Shen, Xuemin (Sherman)

    2017-01-01

    This SpringerBrief offers a comprehensive review and in-depth discussion of the current research on resource management. The authors explain how to best utilize harvested energy and temporally available licensed spectrum. Throughout the brief, the primary focus is energy and spectrum harvesting sensor networks (ESHNs) including energy harvesting (EH)-powered spectrum sensing and dynamic spectrum access. To efficiently collect data through the available licensed spectrum, this brief examines the joint management of energy and spectrum. An EH-powered spectrum sensing and management scheme for Heterogeneous Spectrum Harvesting Sensor Networks (HSHSNs) is presented in this brief. The scheme dynamically schedules the data sensing and spectrum access of sensors in ESHSNs to optimize the network utility, while considering the stochastic nature of EH process, PU activities and channel conditions. This brief also provides useful insights for the practical resource management scheme design for ESHSNs and motivates a ne...

  7. Multiservice Switching Networks with Overflow Links and Resource Reservation

    Directory of Open Access Journals (Sweden)

    Mariusz Głąbowski

    2016-01-01

    Full Text Available This paper proposes a new analytical model of a multiservice switching network with overflow links in the first stage and resource reservation for selected call classes in output directions. The proposed model assumes that both the overflow mechanism and the resource reservation mechanism can be used in a number of selected, or all, classes of calls. A particular attention is given to the way the effective availability parameter for networks with overflow links in the point-to-point selection mode is determined. The proposed model makes it possible to determine dependencies between the internal blocking probability, capacity of overflow links, and the number of reserved resources for call classes to be analysed. Simulation experiments confirm high accuracy of the proposed method and potential applications of the model in engineering issues.

  8. Butterfly Encryption Scheme for Resource-Constrained Wireless Networks

    Directory of Open Access Journals (Sweden)

    Raghav V. Sampangi

    2015-09-01

    Full Text Available Resource-constrained wireless networks are emerging networks such as Radio Frequency Identification (RFID and Wireless Body Area Networks (WBAN that might have restrictions on the available resources and the computations that can be performed. These emerging technologies are increasing in popularity, particularly in defence, anti-counterfeiting, logistics and medical applications, and in consumer applications with growing popularity of the Internet of Things. With communication over wireless channels, it is essential to focus attention on securing data. In this paper, we present an encryption scheme called Butterfly encryption scheme. We first discuss a seed update mechanism for pseudorandom number generators (PRNG, and employ this technique to generate keys and authentication parameters for resource-constrained wireless networks. Our scheme is lightweight, as in it requires less resource when implemented and offers high security through increased unpredictability, owing to continuously changing parameters. Our work focuses on accomplishing high security through simplicity and reuse. We evaluate our encryption scheme using simulation, key similarity assessment, key sequence randomness assessment, protocol analysis and security analysis.

  9. Dynamic Resource Allocation and QoS Control Capabilities of the Japanese Academic Backbone Network

    Directory of Open Access Journals (Sweden)

    Michihiro Aoki

    2010-08-01

    Full Text Available Dynamic resource control capabilities have become increasingly important for academic networks that must support big scientific research projects at the same time as less data intensive research and educational activities. This paper describes the dynamic resource allocation and QoS control capabilities of the Japanese academic backbone network, called SINET3, which supports a variety of academic applications with a wide range of network services. The article describes the network architecture, networking technologies, resource allocation, QoS control, and layer-1 bandwidth on-demand services. It also details typical services developed for scientific research, including the user interface, resource control, and management functions, and includes performance evaluations.

  10. Networking of Biological Resource Centers: WDCM experiences

    Directory of Open Access Journals (Sweden)

    Satoru Miyazaki

    2006-01-01

    Full Text Available The WFCC-MIRCEN World Data Centre for Microorganisms (WDCM was set up more than 30 years ago as a data center of the World Federation for Culture Collections (WFCC. It published the World Directory of Collections of Cultures of Microorganisms when it was established and now provides a portal site for microbial resource centers and their customers by fully utilizing Internet technology. This paper introduces international initiatives on biological resources centers together with the activities of WDCM.

  11. Network resource and applications management at SLAC

    Energy Technology Data Exchange (ETDEWEB)

    Logg, C.A.; Cottrell, R.L.A.

    1996-02-01

    The Stanford Linear Accelerator Center (SLAC) has a heterogeneous networked computing environment with a variety of transmission media, protocols, equipment from multiple vendors, Local Areas Network (LAN) and Wide Area Network (WAN) connections, workstations, servers, legacy mainframes, operating systems, network services and applications, and users of various skill levels. New technologies are continually being deployed as they become available. All of these components work together (most of the time) but result in a complex distributed computing environment (henceforth referred to as the system) which requires automated monitoring and management for the maintenance of high quality performance with limited personnel and budgets. There is no Network Management Station (NMS) product which comes close to doing the job of monitoring and managing the LAN and WAN for SLAC. However, by making use of Ping, Simple Network Management Protocol (SNMP) and its Management Information Bases (MIBs), as well as network applications (trace-route, File Transfer Protocol (FTP), Remote Procedure Calls (RPCs), Remote Shell (rsh), et.al.), an NMS (Netview for AIX), and the accounting and monitoring facilities provided by the server operating systems, the challenge is surmountable.

  12. Habitat, not resource availability, limits consumer production in lake ecosystems

    Science.gov (United States)

    Craig, Nicola; Jones, Stuart E.; Weidel, Brian C.; Solomon, Christopher T.

    2015-01-01

    Food web productivity in lakes can be limited by dissolved organic carbon (DOC), which reduces fish production by limiting the abundance of their zoobenthic prey. We demonstrate that in a set of 10 small, north temperate lakes spanning a wide DOC gradient, these negative effects of high DOC concentrations on zoobenthos production are driven primarily by availability of warm, well-oxygenated habitat, rather than by light limitation of benthic primary production as previously proposed. There was no significant effect of benthic primary production on zoobenthos production after controlling for oxygen, even though stable isotope analysis indicated that zoobenthos do use this resource. Mean whole-lake zoobenthos production was lower in high-DOC lakes with reduced availability of oxygenated habitat, as was fish biomass. These insights improve understanding of lake food webs and inform management in the face of spatial variability and ongoing temporal change in lake DOC concentrations.

  13. Cooperative Radio Resource Management for Heterogeneous Networks

    DEFF Research Database (Denmark)

    Mihovska, Albena D.; Tragos, Elias; Luo, Jijun

    2009-01-01

    that an interworking model is flexible and generic enough to include any new type of network that might be designed in the future and that will require inclusion in the heterogeneous domain. Finally, ubiquitous communication systems and the challenge to deploy them successfully bring also the problem of how to manage...... of the network’s resources. This is also the reason why researchers look for systems that are adaptive and flexible and provide coverage in various deployment modes (wide area, metropolitan area and local area). Cooperation and coexistence then extends from interworking between different PHY layer modes...

  14. Butterfly Encryption Scheme for Resource-Constrained Wireless Networks.

    Science.gov (United States)

    Sampangi, Raghav V; Sampalli, Srinivas

    2015-09-15

    Resource-constrained wireless networks are emerging networks such as Radio Frequency Identification (RFID) and Wireless Body Area Networks (WBAN) that might have restrictions on the available resources and the computations that can be performed. These emerging technologies are increasing in popularity, particularly in defence, anti-counterfeiting, logistics and medical applications, and in consumer applications with growing popularity of the Internet of Things. With communication over wireless channels, it is essential to focus attention on securing data. In this paper, we present an encryption scheme called Butterfly encryption scheme. We first discuss a seed update mechanism for pseudorandom number generators (PRNG), and employ this technique to generate keys and authentication parameters for resource-constrained wireless networks. Our scheme is lightweight, as in it requires less resource when implemented and offers high security through increased unpredictability, owing to continuously changing parameters. Our work focuses on accomplishing high security through simplicity and reuse. We evaluate our encryption scheme using simulation, key similarity assessment, key sequence randomness assessment, protocol analysis and security analysis.

  15. Quantifying the Available Offshore Wind Resource in North Carolina

    Science.gov (United States)

    Schutt, M.; Seim, H.

    2016-02-01

    We present a study of wind profile measurements for improvement upon the wind resource estimation of coastal North Carolina. The site of measurement, near Cape Hatteras, is interesting because of its proximity to an open sound condition to the north and west, as well as its oceanic boundary to the south and east, including the thermally dynamic influence of the Gulf Stream. Such an environment has been found to complicate wind speed estimation at wind turbine hub height. Early exploration of the profiles collected during 2012-2014 from the surface to 200 m revealed distinct characteristics unique to winds coming from Pamlico Sound, as compared to those coming from the Atlantic. In order to quantify the effect of atmospheric stability on the wind profiles, an aggregation of ancillary data was collected, including surface sea and air temperature, and surface humidity to calculate a Monin-Obukhov Similarity scaling parameter. The ancillary data, in combination with knowledge of upwind conditions, topography, and ocean thermal structure, is being used to test the ability of simple theory to reproduce the structure of wind profiles from the two environments assuming nested internal boundary layers. This work will provide a more refined method of estimating the available wind resource for use in offshore wind energy development in this particular coastal region.

  16. Impact of SDN Controllers Deployment on Network Availability

    OpenAIRE

    Nencioni, Gianfranco; Helvik, Bjarne Emil; Gonzalez, Andres Javier; Heegaard, Poul Einar; Kamisinski, Andrzej

    2016-01-01

    Software-defined networking (SDN) promises to improve the programmability and flexibility of networks, but it may bring also new challenges that need to be explored. The purpose of this technical report is to assess how the deployment of the SDN controllers affects the overall availability of SDN. For this, we have varied the number, homing and location of SDN controllers. A two-level modelling approach that is used to evaluate the availability of the studied scenarios. Our results show how n...

  17. Ensuring GRID resource availability with the SAM framework in LHCb

    Science.gov (United States)

    Closier, J.; Paterson, S.; Santinelli, R.

    2008-07-01

    The LHCb experiment has chosen to use the SAM framework (Service Availability Monitoring Environment from EGEE-II) [1] make extensive tests of the LHCb environment at all the accessible grid resources. The availability and the proper definition of the local Computing and Storage Elements, user interfaces as well as the WLCG software environment are checked. The SAM framework is also used to pre-install the LHCb applications in the shared software area provided by each site. The deployment of the LHCb applications is based on a python tool developed inside the experiment. It is used for software management including incremental installation of interdependent packages and clean package removal. After the application software is installed a validation test of the whole MC chain is run. According to the results of the experiment specific SAM tests, the sites are (re)integrated into the LHCb production system managed by DIRAC [2]. The possibility of automated dynamic site certification using the SAM test suite is explored. This paper will describe the various ways of the LHCb use of the SAM framework. Practical experience in the recent production runs, current limitations and future developments will be presented.

  18. Virtualized cloud data center networks issues in resource management

    CERN Document Server

    Tsai, Linjiun

    2016-01-01

    This book discusses the characteristics of virtualized cloud networking, identifies the requirements of cloud network management, and illustrates the challenges in deploying virtual clusters in multi-tenant cloud data centers. The book also introduces network partitioning techniques to provide contention-free allocation, topology-invariant reallocation, and highly efficient resource utilization, based on the Fat-tree network structure. Managing cloud data center resources without considering resource contentions among different cloud services and dynamic resource demands adversely affects the performance of cloud services and reduces the resource utilization of cloud data centers. These challenges are mainly due to strict cluster topology requirements, resource contentions between uncooperative cloud services, and spatial/temporal data center resource fragmentation. Cloud data center network resource allocation/reallocation which cope well with such challenges will allow cloud services to be provisioned with ...

  19. Hybrid SDN Architecture for Resource Consolidation in MPLS Networks

    DEFF Research Database (Denmark)

    Katov, Anton Nikolaev; Mihovska, Albena D.; Prasad, Neeli R.

    2015-01-01

    This paper proposes a methodology for resource consolidation towards minimizing the power consumption in a large network, with a substantial resource overprovisioning. The focus is on the operation of the core MPLS networks. The proposed approach is based on a software defined networking (SDN...

  20. Maintaining Mobile Network Coverage Availability in Disturbance Scenarios

    Directory of Open Access Journals (Sweden)

    Joonas Säe

    2016-01-01

    Full Text Available Disturbance and disaster scenarios prevent the normal utilization of mobile networks. The aim of this study is to maintain the availability of cellular networks in disturbance scenarios. In order to extend the disaster time functionality, energy usage optimization is needed to maintain reasonable coverage and capacity. Simulations performed with different network layouts show the effects of choosing only a portion of evolved node B (eNB macrosites to operate at a time. Different sets of three to nine three-sectored eNB sites are selected to study how the network would perform with a limited number of eNB sites. Simulation results show how the mobile network availability duration can be sustained by selecting a set of eNB sites to operate at a time and still maintain a reasonable service level and availability in disturbance scenarios. An increase of 100% to 500% can be achieved in the duration of “backup coverage” in cellular networks with backup batteries when the percentage of active eNB sites is reduced down to 20%.

  1. Network resource control for grid workflow management systems

    NARCIS (Netherlands)

    Strijkers, R.J.; Cristea, M.; Korkhov, V.; Marchal, D.; Belloum, A.; Laat, C.de; Meijer, R.J.

    2010-01-01

    Grid workflow management systems automate the orchestration of scientific applications with large computational and data processing needs, but lack control over network resources. Consequently, the management system cannot prevent multiple communication intensive applications to compete for network

  2. Medical Optimization Network for Space Telemedicine Resources

    Science.gov (United States)

    Shah, R. V.; Mulcahy, R.; Rubin, D.; Antonsen, E. L.; Kerstman, E. L.; Reyes, D.

    2017-01-01

    INTRODUCTION: Long-duration missions beyond low Earth orbit introduce new constraints to the space medical system such as the inability to evacuate to Earth, communication delays, and limitations in clinical skillsets. NASA recognizes the need to improve capabilities for autonomous care on such missions. As the medical system is developed, it is important to have an ability to evaluate the trade space of what resources will be most important. The Medical Optimization Network for Space Telemedicine Resources was developed for this reason, and is now a system to gauge the relative importance of medical resources in addressing medical conditions. METHODS: A list of medical conditions of potential concern for an exploration mission was referenced from the Integrated Medical Model, a probabilistic model designed to quantify in-flight medical risk. The diagnostic and treatment modalities required to address best and worst-case scenarios of each medical condition, at the terrestrial standard of care, were entered into a database. This list included tangible assets (e.g. medications) and intangible assets (e.g. clinical skills to perform a procedure). A team of physicians working within the Exploration Medical Capability Element of NASA's Human Research Program ranked each of the items listed according to its criticality. Data was then obtained from the IMM for the probability of occurrence of the medical conditions, including a breakdown of best case and worst case, during a Mars reference mission. The probability of occurrence information and criticality for each resource were taken into account during analytics performed using Tableau software. RESULTS: A database and weighting system to evaluate all the diagnostic and treatment modalities was created by combining the probability of condition occurrence data with the criticalities assigned by the physician team. DISCUSSION: Exploration Medical Capabilities research at NASA is focused on providing a medical system to

  3. Resource Allocation in Heterogeneous Buffered Cognitive Radio Networks

    Directory of Open Access Journals (Sweden)

    B. S. Awoyemi

    2017-01-01

    Full Text Available Resources available for operation in cognitive radio networks (CRN are generally limited, making it imperative for efficient resource allocation (RA models to be designed for them. However, in most RA designs, a significant limiting factor to the RA’s productivity has hitherto been mostly ignored, the fact that different users or user categories do have different delay tolerance profiles. To address this, in this paper, an appropriate RA model for heterogeneous CRN with delay considerations is developed and analysed. In the model, the demands of users are first categorised and then, based on the distances of users from the controlling secondary user base station and with the assumption that the users are mobile, the user demands are placed in different queues having different service capacities and the resulting network is analysed using queueing theory. Furthermore, to achieve optimality in the RA process, an important concept is introduced whereby some demands from one queue are moved to another queue where they have a better chance of enhanced service, thereby giving rise to the possibility of an improvement in the overall performance of the network. The performance results obtained from the analysis, particularly the blocking probability and network throughput, show that the queueing model incorporated into the RA process can help in achieving optimality for the heterogeneous CRN with buffered data.

  4. Asymmetric Branching in Biological Resource Distribution Networks

    Science.gov (United States)

    Brummer, Alexander Byers

    There is a remarkable relationship between an organism's metabolic rate (resting power consumption) and the organism's mass. It may be a universal law of nature that an organism's resting metabolic rate is proportional to its mass to the power of 3/4. This relationship, known as Kleiber's Law, appears to be valid for both plants and animals. This law is important because it implies that larger organisms are more efficient than smaller organisms, and knowledge regarding metabolic rates are essential to a multitude of other fields in ecology and biology. This includes modeling the interactions of many species across multiple trophic levels, distributions of species abundances across large spatial landscapes, and even medical diagnostics for respiratory and cardiovascular pathologies. Previous models of vascular networks that seek to identify the origin of metabolic scaling have all been based on the unrealistic assumption of perfectly symmetric branching. In this dissertation I will present a theory of asymmetric branching in self-similar vascular networks (published by Brummer et al. in [9]). The theory shows that there can exist a suite of vascular forms that result in the often observed 3/4 metabolic scaling exponent of Kleiber's Law. Furthermore, the theory makes predictions regarding major morphological features related to vascular branching patterns and their relationships to metabolic scaling. These predictions are suggestive of evolutionary convergence in vascular branching. To test these predictions, I will present an analysis of real mammalian and plant vascular data that shows: (i) broad patterns in vascular networks across entire animal kingdoms and (ii) within these patterns, plant and mammalian vascular networks can be uniquely distinguished from one another (publication in preparation by Brummer et al.). I will also present results from a computational study in support of point (i). Namely, that asymmetric branching may be the optimal strategy to

  5. Enhancing Availability of Services Using Software-Defined Networking

    Directory of Open Access Journals (Sweden)

    Martin Klepac

    2015-01-01

    Full Text Available The immense growth of client requirements imposed on data centre and cloud providers results in a conflict with traditional networking concepts lacking the required agility. In order to promote flexibility, which data centre providers promise to their clients, this discrepancy needs to be resolved, for instance by employing the novel concept of Software-Defined Networking (SDN. This paper utilises this concept in order to minimise service downtime while performing live virtual machine migration. The work is aimed at small/medium-sized data centres and hence the findings are based on real communication patterns found in such environments. Results show that packet loss is slightly diminished while available throughput is increased thanks to the proactive approach taken during network topology changes when compared to the traditional approach based on L2 forwarding.

  6. Resource Allocation for Cloud Radio Access Networks

    KAUST Repository

    Dhifallah, Oussama

    2016-04-01

    assumes that only imperfect channel state information (CSI) is available at the cloud. This part focuses on jointly minimizing the network total power consumption as well as backhaul cost. It then suggests solving this optimization problem using the majorization-minimization (MM) approach. Simulation results show that the proposed algorithm converges in a reasonable number of iterations.

  7. EDUCATIONAL NETWORK RESOURCES IN JOURNALISM AND PUBLISHING: FEATURES OF THE SITES' CONTENT AND DESIGN

    Directory of Open Access Journals (Sweden)

    Hanna A. Zenzina

    2012-12-01

    Full Text Available The article deals with the concept of electronic educational resource, its importance for the orientation of students in cyberspace, the basic requirements for the design and content of educational resources eligibility criteria standards. Filed benefits of having their own educational resource for high school. Singled out the importance of the interaction of educational resources with social networks. Detected differences and similarities of design and content of educational resources of Kyiv Universities in journalism and publishing.

  8. AVAILABILITY RESEARCH OF REMOTE DEVICES FOR WIRELESS NETWORKS

    Directory of Open Access Journals (Sweden)

    N. A. Bazhayev

    2016-05-01

    Full Text Available We consider the wireless network under attack, aimed at "broadcast storm" initiation, in order to determine the availability of stand-alone units and the ability to carry out their functional tasks under information exposure. We determine a set of conditions for such type of attacks on the part of potential information interloper. The functional analysis of the systems based on wireless technology is made. We examine the remote device of a self-organizing wireless network as a queuing system M/M/1/n. Model dependencies are shown for normal system performance and at information exposure on the part of potential information interloper. Analytical simulation of wireless network functioning is carried out in the normal mode and under the attack aimed at "broadcast storm" initiation. An experiment is described which provides statistical information on operation of network remote devices. We present experiment results on carrying out attack at typical system transferring data by broabcast net scanning package at different noise intensities on the part of information interloper. The proposed model can be used to determine the technical characteristics of wireless ad-hoc network, develop recommendations for node configuration, aimed at countering "broadcast storm".

  9. Real-time probing of available bandwidth in home networks

    NARCIS (Netherlands)

    Delphinanto, A.; Koonen, T.; Hartog, F.T.H. den

    2011-01-01

    Prioritization of flows in a home network based on traffic classification is still no guarantee that enough bandwidth will be available between a content server and a client. Besides, such QoS technologies need to be supported by every device in the end-to-end path to be effective, which is

  10. Availability and Type of Human Resource for Health in Public ...

    African Journals Online (AJOL)

    adedamla

    1 care process. The implementation of PHC is primarily through services carried out at the primary health centres and this can only be achieved by the human force (Human Resources for Health) at these. 2-5 centres. Health workers are defined as all persons eligible to participate in the national health labour market by. 6.

  11. Energy Efficient Resource Allocation for Phantom Cellular Networks

    KAUST Repository

    Abdelhady, Amr

    2016-04-01

    Multi-tier heterogeneous networks have become an essential constituent for next generation cellular networks. Meanwhile, energy efficiency (EE) has been considered a critical design criterion along with the traditional spectral efficiency (SE) metric. In this context, we study power and spectrum allocation for the recently proposed two-tier network architecture known as phantom cellular networks. The optimization framework includes both EE and SE. First, we consider sparsely deployed cells experiencing negligible interference and assume perfect channel state information (CSI). For this setting, we propose an algorithm that finds the SE and EE resource allocation strategies. Then, we compare the performance of both design strategies versus number of users, and phantom cells share of the total available resource units (RUs). We aim to investigate the effect of some system parameters to achieve improved SE performance at a non-significant loss in EE performance, or vice versa. It is found that increasing phantom cells share of RUs decreases the SE performance loss due to EE optimization when compared with the optimized SE performance. Second, we consider the densely deployed phantom cellular networks and model the EE optimization problem having into consideration the inevitable interference and imperfect channel estimation. To this end, we propose three resource allocation strategies aiming at optimizing the EE performance metric of this network. Furthermore, we investigate the effect of changing some of the system parameters on the performance of the proposed strategies, such as phantom cells share of RUs, number of deployed phantom cells within a macro cell coverage, number of pilots and the maximum power available for transmission by the phantom cells BSs. It is found that increasing the number of pilots deteriorates the EE performance of the whole setup, while increasing maximum power available for phantom cells transmissions reduces the EE of the whole setup in a

  12. Monitoring Network and Service Availability with Open-Source Software

    Directory of Open Access Journals (Sweden)

    T. Michael Silver

    2010-03-01

    Full Text Available Silver describes the implementation of a monitoring system using an open-source software package to improve the availability of services and reduce the response time when troubles occur. He provides a brief overview of the literature available on monitoring library systems, and then describes the implementation of Nagios, an open-source network monitoring system, to monitor a regional library system’s servers and wide area network. Particular attention is paid to using the plug-in architecture to monitor library services effectively. The author includes example displays and configuration files.   Editor’s note: This article is the winner of the LITA/Ex Libris Writing Award, 2009.

  13. Analyses of resource reservation schemes for optical burst switching networks

    Science.gov (United States)

    Solanska, Michaela; Scholtz, Lubomir; Ladanyi, Libor; Mullerova, Jarmila

    2017-12-01

    With growing demands of Internet Protocol services for transmission capacity and speed, the Optical Burst Switching presents the solution for future high-speed optical networks. Optical Burst Switching is a technology for transmitting large amounts of data bursts through a transparent optical switching network. To successfully transmit bursts over OBS network and reach the destination node, resource reservation schemes have to be implemented to allocate resources and configure optical switches for that burst at each node. The one-way resource reservation schemes and the performance evaluation of reservation schemes are presented. The OBS network model is performed using OMNeT++ simulation environment. During the reservation of network resources, the optical cross-connect based on semiconductor optical amplifier is used as the core node. Optical switches based on semiconductor optical amplifiers are a promising technology for high-speed optical communication networks.

  14. Optimal resource allocation for efficient transport on complex networks

    Science.gov (United States)

    Gong, Xiaofeng; Kun, Li; Lai, C.-H.

    2008-07-01

    The problem of efficient transport on a complex network is studied in this paper. We find that there exists an optimal way to allocate resources for information processing on each node to achieve the best transport capacity of the network, or the largest input information rate which does not cause jamming in network traffic, provided that the network structure and routing strategy are given. More interestingly, this achievable network capacity limit is closely related to the topological structure of the network, and is actually inversely proportional to the average distance of the network, measured according to the same routing rule.

  15. Resource Allocation Optimization Model of Collaborative Logistics Network Based on Bilevel Programming

    Directory of Open Access Journals (Sweden)

    Xiao-feng Xu

    2017-01-01

    Full Text Available Collaborative logistics network resource allocation can effectively meet the needs of customers. It can realize the overall benefit maximization of the logistics network and ensure that collaborative logistics network runs orderly at the time of creating value. Therefore, this article is based on the relationship of collaborative logistics network supplier, the transit warehouse, and sellers, and we consider the uncertainty of time to establish a bilevel programming model with random constraints and propose a genetic simulated annealing hybrid intelligent algorithm to solve it. Numerical example shows that the method has stronger robustness and convergence; it can achieve collaborative logistics network resource allocation rationalization and optimization.

  16. Network Slicing Based 5G and Future Mobile Networks: Mobility, Resource Management, and Challenges

    OpenAIRE

    Zhang, H.; Liu, N.; Chu, X; Long, K.; Aghvami, A.; Leung, V. C. M.

    2017-01-01

    The fifth-generation (5G) networks are expected to be able to satisfy users' different quality-of-service (QoS) requirements. Network slicing is a promising technology for 5G networks to provide services tailored for users' specific QoS demands. Driven by the increased massive wireless data traffic from different application scenarios, efficient resource allocation schemes should be exploited to improve the flexibility of network resource allocation and capacity of 5G networks based on networ...

  17. 76 FR 59156 - Notice of Availability of the Proposed Ironwood Forest National Monument Resource Management Plan...

    Science.gov (United States)

    2011-09-23

    ... Resource Management Plan/Final EIS AGENCY: Bureau of Land Management. ACTION: Notice of Availability... Proposed Resource Management Plan (RMP)/Final Environmental Impact Statement (EIS) for the Ironwood Forest... Proposed RMP/Final EIS include air resources, biological resources, cultural resources, fire management...

  18. 75 FR 36435 - Notice of Availability of the Draft Winnemucca District Resource Management Plan and...

    Science.gov (United States)

    2010-06-25

    ...:14X1109] Notice of Availability of the Draft Winnemucca District Resource Management Plan and... prepared a Draft Resource Management Plan (RMP) and Draft Environmental Impact Statement (EIS) for the... address air resources, biological resources, cultural resources, fire management, grazing management...

  19. Experimental FSO network availability estimation using interactive fog condition monitoring

    Science.gov (United States)

    Turán, Ján.; Ovseník, Łuboš

    2016-12-01

    Free Space Optics (FSO) is a license free Line of Sight (LOS) telecommunication technology which offers full duplex connectivity. FSO uses infrared beams of light to provide optical broadband connection and it can be installed literally in a few hours. Data rates go through from several hundreds of Mb/s to several Gb/s and range is from several 100 m up to several km. FSO link advantages: Easy connection establishment, License free communication, No excavation are needed, Highly secure and safe, Allows through window connectivity and single customer service and Compliments fiber by accelerating the first and last mile. FSO link disadvantages: Transmission media is air, Weather and climate dependence, Attenuation due to rain, snow and fog, Scattering of laser beam, Absorption of laser beam, Building motion and Air pollution. In this paper FSO availability evaluation is based on long term measured data from Fog sensor developed and installed at TUKE experimental FSO network in TUKE campus, Košice, Slovakia. Our FSO experimental network has three links with different physical distances between each FSO heads. Weather conditions have a tremendous impact on FSO operation in terms of FSO availability. FSO link availability is the percentage of time over a year that the FSO link will be operational. It is necessary to evaluate the climate and weather at the actual geographical location where FSO link is going to be mounted. It is important to determine the impact of a light scattering, absorption, turbulence and receiving optical power at the particular FSO link. Visibility has one of the most critical influences on the quality of an FSO optical transmission channel. FSO link availability is usually estimated using visibility information collected from nearby airport weather stations. Raw data from fog sensor (Fog Density, Relative Humidity, Temperature measured at each ms) are collected and processed by FSO Simulator software package developed at our Department. Based

  20. Comparison of Available Bandwidth Estimation Techniques in Packet-Switched Mobile Networks

    DEFF Research Database (Denmark)

    López Villa, Dimas; Ubeda Castellanos, Carlos; Teyeb, Oumer Mohammed

    2006-01-01

    of information regarding the available bandwidth in the transport network, as it could end up being the bottleneck rather than the air interface. This paper provides a comparative study of three well known available bandwidth estimation techniques, i.e. TOPP, SLoPS and pathChirp, taking into account......The relative contribution of the transport network towards the per-user capacity in mobile telecommunication systems is becoming very important due to the ever increasing air-interface data rates. Thus, resource management procedures such as admission, load and handover control can make use...... the statistical conditions of the available bandwidth and assessing the variability of their estimations. Simulation-based studies on a mobile transport network show that pathChirp outperforms TOPP and SLoPS, both in terms of accuracy and efficiency....

  1. Energy wood resources availability and delivery cost in Northwest Russia

    Energy Technology Data Exchange (ETDEWEB)

    Gerasimov, Yuri; Karjalainen, Timo [Finnish Forest Research Inst., Joensuu (Finland)], E-mail: yuri.gerasimov@metla.fi

    2013-10-01

    Availability of solid by-products from wood harvesting and mechanical wood processing was estimated as sources for energy production based on recent actual harvesting, sawmill, and plywood production in Northwest Russia at 30 million m{sup 3}. Nearly 70% of the energy wood, 20 million m{sup 3}, was from harvesting, consisting of non-industrial round wood, unused branches and tops, defective wood resulting from logging, and spruce stumps removed after final felling. Over 30%, 10 million m{sup 3}, of the available volume was from sawmills and plywood mills, i.e. wood chips, sawdust, and bark. Due to current low utilization of energy wood for bioenergy in Northwest Russia, delivery cost of energy wood to the potential border-crossing points in Finland was analyzed for three means of transport: railways, roadways, and waterways. Nearly 28 million m{sup 3} of the energy wood could be transported by railways and 2 million m{sup 3} by roadways and waterways. The costs were lowest by roadways from the nearby border areas (10-15 Euro/m{sup 3} for wood processing by-products and 16-22 Euro/m{sup 3} for forest chips). The costs by railways varied from 12 to 27 Euro/m{sup 3} on shorter distances to 47-58 Euro/m{sup 3} on longer distances. Waterway transportation was the most expensive, about 28-48 Euro/m{sup 3}. It should be emphasized that we have estimated availability and delivery costs of energy wood, not prices which are defined by the market based on supply and demand.

  2. pathChirp: Efficient Available Bandwidth Estimation for Network Paths

    Energy Technology Data Exchange (ETDEWEB)

    Cottrell, Les

    2003-04-30

    This paper presents pathChirp, a new active probing tool for estimating the available bandwidth on a communication network path. Based on the concept of ''self-induced congestion,'' pathChirp features an exponential flight pattern of probes we call a chirp. Packet chips offer several significant advantages over current probing schemes based on packet pairs or packet trains. By rapidly increasing the probing rate within each chirp, pathChirp obtains a rich set of information from which to dynamically estimate the available bandwidth. Since it uses only packet interarrival times for estimation, pathChirp does not require synchronous nor highly stable clocks at the sender and receiver. We test pathChirp with simulations and Internet experiments and find that it provides good estimates of the available bandwidth while using only a fraction of the number of probe bytes that current state-of-the-art techniques use.

  3. Resource Optimization Scheme for Multimedia-Enabled Wireless Mesh Networks

    Science.gov (United States)

    Ali, Amjad; Ahmed, Muhammad Ejaz; Piran, Md. Jalil; Suh, Doug Young

    2014-01-01

    Wireless mesh networking is a promising technology that can support numerous multimedia applications. Multimedia applications have stringent quality of service (QoS) requirements, i.e., bandwidth, delay, jitter, and packet loss ratio. Enabling such QoS-demanding applications over wireless mesh networks (WMNs) require QoS provisioning routing protocols that lead to the network resource underutilization problem. Moreover, random topology deployment leads to have some unused network resources. Therefore, resource optimization is one of the most critical design issues in multi-hop, multi-radio WMNs enabled with multimedia applications. Resource optimization has been studied extensively in the literature for wireless Ad Hoc and sensor networks, but existing studies have not considered resource underutilization issues caused by QoS provisioning routing and random topology deployment. Finding a QoS-provisioned path in wireless mesh networks is an NP complete problem. In this paper, we propose a novel Integer Linear Programming (ILP) optimization model to reconstruct the optimal connected mesh backbone topology with a minimum number of links and relay nodes which satisfies the given end-to-end QoS demands for multimedia traffic and identification of extra resources, while maintaining redundancy. We further propose a polynomial time heuristic algorithm called Link and Node Removal Considering Residual Capacity and Traffic Demands (LNR-RCTD). Simulation studies prove that our heuristic algorithm provides near-optimal results and saves about 20% of resources from being wasted by QoS provisioning routing and random topology deployment. PMID:25111241

  4. Resource optimization scheme for multimedia-enabled wireless mesh networks.

    Science.gov (United States)

    Ali, Amjad; Ahmed, Muhammad Ejaz; Piran, Md Jalil; Suh, Doug Young

    2014-08-08

    Wireless mesh networking is a promising technology that can support numerous multimedia applications. Multimedia applications have stringent quality of service (QoS) requirements, i.e., bandwidth, delay, jitter, and packet loss ratio. Enabling such QoS-demanding applications over wireless mesh networks (WMNs) require QoS provisioning routing protocols that lead to the network resource underutilization problem. Moreover, random topology deployment leads to have some unused network resources. Therefore, resource optimization is one of the most critical design issues in multi-hop, multi-radio WMNs enabled with multimedia applications. Resource optimization has been studied extensively in the literature for wireless Ad Hoc and sensor networks, but existing studies have not considered resource underutilization issues caused by QoS provisioning routing and random topology deployment. Finding a QoS-provisioned path in wireless mesh networks is an NP complete problem. In this paper, we propose a novel Integer Linear Programming (ILP) optimization model to reconstruct the optimal connected mesh backbone topology with a minimum number of links and relay nodes which satisfies the given end-to-end QoS demands for multimedia traffic and identification of extra resources, while maintaining redundancy. We further propose a polynomial time heuristic algorithm called Link and Node Removal Considering Residual Capacity and Traffic Demands (LNR-RCTD). Simulation studies prove that our heuristic algorithm provides near-optimal results and saves about 20% of resources from being wasted by QoS provisioning routing and random topology deployment.

  5. Practical guidance on characterizing availability in resource selection functions under a use-availability design.

    Science.gov (United States)

    Northrup, Joseph M; Hooten, Mevin B; Anderson, Charles R; Wittemyer, George

    2013-07-01

    Habitat selection is a fundamental aspect of animal ecology, the understanding of which is critical to management and conservation. Global positioning system data from animals allow fine-scale assessments of habitat selection and typically are analyzed in a use availability framework, whereby animal locations are contrasted with random locations (the availability sample). Although most use-availability methods are in fact spatial point process models, they often are fit using logistic regression. This framework offers numerous methodological challenges, for which the literature provides little guidance. Specifically, the size and spatial extent of the availability sample influences coefficient estimates potentially causing interpretational bias. We examined the influence of availability on statistical inference through simulations and analysis of serially correlated mule deer GPS data. Bias in estimates arose from incorrectly assessing and sampling the spatial extent of availability. Spatial autocorrelation in covariates, which is common for landscape characteristics, exacerbated the error in availability sampling leading to increased bias. These results have strong implications for habitat selection analyses using GPS data, which are increasingly prevalent in the literature. We recommend that researchers assess the sensitivity of their results to their availability sample and, where bias is likely, take care with interpretations and use cross validation to assess robustness.

  6. Radio resource management in multi-tier cellular wireless networks

    CERN Document Server

    Hossain, Ekram; Niyato, Dusit

    2013-01-01

    Providing an extensive overview of the radio resource management problem in femtocell networks, this invaluable book considers both code division multiple access femtocells and orthogonal frequency-division multiple access femtocells. In addition to incorporating current research on this topic, the book also covers technical challenges in femtocell deployment, provides readers with a variety of approaches to resource allocation and a comparison of their effectiveness, explains how to model various networks using Stochastic geometry and shot noise theory, and much more.

  7. 76 FR 72718 - Notice of Availability of the Draft Baker Resource Management Plan and Environmental Impact...

    Science.gov (United States)

    2011-11-25

    ... Bureau of Land Management Notice of Availability of the Draft Baker Resource Management Plan and...) has prepared a Draft Resource Management Plan (RMP) and Draft Environmental Impact Statement (EIS) for... in resource conditions, and changes in resource management practices since the Baker RMP of 1989. The...

  8. 75 FR 25288 - Notice of Availability of the Proposed Resource Management Plan and Final Environmental Impact...

    Science.gov (United States)

    2010-05-07

    ... Bureau of Land Management Notice of Availability of the Proposed Resource Management Plan and Final... Management (BLM) has prepared a Proposed Resource Management Plan/Final Environmental Impact Statement... completed, will provide management direction for resources and resource uses. Planning issues addressed in...

  9. Virtual Network Embedding: A Hybrid Vertex Mapping Solution for Dynamic Resource Allocation

    Directory of Open Access Journals (Sweden)

    Adil Razzaq

    2012-01-01

    Full Text Available Virtual network embedding (VNE is a key area in network virtualization, and the overall purpose of VNE is to map virtual networks onto an underlying physical network referred to as a substrate. Typically, the virtual networks have certain demands, such as resource requirements, that need to be satisfied by the mapping process. A virtual network (VN can be described in terms of vertices (nodes and edges (links with certain resource requirements, and, to embed a VN, substrate resources are assigned to these vertices and edges. Substrate networks have finite resources and utilizing them efficiently is an important objective for a VNE method. This paper analyzes two existing vertex mapping approaches—one which only considers if enough node resources are available for the current VN mapping and one which considers to what degree a node already is utilized by existing VN embeddings before doing the vertex mapping. The paper also proposes a new vertex mapping approach which minimizes complete exhaustion of substrate nodes while still providing good overall resource utilization. Experimental results are presented to show under what circumstances the proposed vertex mapping approach can provide superior VN embedding properties compared to the other approaches.

  10. Resource Sharing in Heterogeneous and Cloud Radio Access Networks

    DEFF Research Database (Denmark)

    Zakrzewska, Anna; Iversen, Villy Bæk

    2012-01-01

    This paper analyzes performance of cellular systems with shared resources, where the network with overlapping cells is modeled as a circuit switched network with direct routing. The influence of the degree of sharing, represented by cell overlap percentage, on the call blocking probability is inv...

  11. Online experimentation and interactive learning resources for teaching network engineering

    OpenAIRE

    Mikroyannidis, Alexander; Gomez-Goiri, Aitor; Smith, Andrew; Domingue, John

    2017-01-01

    This paper presents a case study on teaching network engineering in conjunction with interactive learning resources. This case study has been developed in collaboration with the Cisco Networking Academy in the context of the FORGE project, which promotes online learning and experimentation by offering access to virtual and remote labs. The main goal of this work is allowing learners and educators to perform network simulations within a web browser or an interactive eBook by using any type of ...

  12. Radio Resource Management in WiMAX Networks

    NARCIS (Netherlands)

    Jorguseski, L.; Prasad, R.

    2010-01-01

    This chapter presents the general Radio Resource Management (RRM) problem in wireless access networks and gives performance evaluations for different downlink resource (sub-carrier) allocation algorithms in WiMAX TDD systems based on OFDMA wireless access. This is particularly important in downlink

  13. Joint Resource Allocation for Dual - Band Heterogeneous Wireless Network

    DEFF Research Database (Denmark)

    Adeogun, Ramoni

    2018-01-01

    In this paper, we investigate downlink resource allocation in two-tier OFDMA heterogeneous networks comprising a macrocell transmitting at a microwave frequency and dual band small cells utilizing both microwave and millimeter wave frequencies. A non - cooperative game theoretic approach is propo...... consumption. The performance of the proposed resource allocation solution is evaluated via rigorous MATLAB simulations...

  14. Quality-Aware Resource Management for Wireless Sensor Networks

    NARCIS (Netherlands)

    Gemesi, R.; Meratnia, Nirvana; Havinga, Paul J.M.; Anderson, J.H.; Prencipe, G.; Wattenhoffer, R.

    2005-01-01

    Due to the distributed and resource constrained nature of wireless sensor networks, their design proves to be difficult. We present a resource management framework, which integrates a data-centric lightweight operating system with a publish/subscribe middleware. In this framework, the main system

  15. Bayesian belief networks: applications in ecology and natural resource management.

    Science.gov (United States)

    R.K. McCann; B.G. Marcot; R. Ellis

    2006-01-01

    We review the use of Bayesian belief networks (BBNs) in natural resource management and ecology. We suggest that BBNs are useful tools for representing expert knowledge of a system, evaluating potential effects of alternative management decisions, and communicating to nonexperts about resource decision issues. BBNs can be used effectively to represent uncertainty in...

  16. Characterization of Energy Availability in RF Energy Harvesting Networks

    Directory of Open Access Journals (Sweden)

    Daniela Oliveira

    2016-01-01

    Full Text Available The multiple nodes forming a Radio Frequency (RF Energy Harvesting Network (RF-EHN have the capability of converting received electromagnetic RF signals in energy that can be used to power a network device (the energy harvester. Traditionally the RF signals are provided by high power transmitters (e.g., base stations operating in the neighborhood of the harvesters. Admitting that the transmitters are spatially distributed according to a spatial Poisson process, we start by characterizing the distribution of the RF power received by an energy harvester node. Considering Gamma shadowing and Rayleigh fading, we show that the received RF power can be approximated by the sum of multiple Gamma distributions with different scale and shape parameters. Using the distribution of the received RF power, we derive the probability of a node having enough energy to transmit a packet after a given amount of charging time. The RF power distribution and the probability of a harvester having enough energy to transmit a packet are validated through simulation. The numerical results obtained with the proposed analysis are close to the ones obtained through simulation, which confirms the accuracy of the proposed analysis.

  17. Research and application of knowledge resources network for product innovation.

    Science.gov (United States)

    Li, Chuan; Li, Wen-qiang; Li, Yan; Na, Hui-zhen; Shi, Qian

    2015-01-01

    In order to enhance the capabilities of knowledge service in product innovation design service platform, a method of acquiring knowledge resources supporting for product innovation from the Internet and providing knowledge active push is proposed. Through knowledge modeling for product innovation based on ontology, the integrated architecture of knowledge resources network is put forward. The technology for the acquisition of network knowledge resources based on focused crawler and web services is studied. Knowledge active push is provided for users by user behavior analysis and knowledge evaluation in order to improve users' enthusiasm for participation in platform. Finally, an application example is illustrated to prove the effectiveness of the method.

  18. Living in a network of scaling cities and finite resources.

    Science.gov (United States)

    Qubbaj, Murad R; Shutters, Shade T; Muneepeerakul, Rachata

    2015-02-01

    Many urban phenomena exhibit remarkable regularity in the form of nonlinear scaling behaviors, but their implications on a system of networked cities has never been investigated. Such knowledge is crucial for our ability to harness the complexity of urban processes to further sustainability science. In this paper, we develop a dynamical modeling framework that embeds population-resource dynamics-a generalized Lotka-Volterra system with modifications to incorporate the urban scaling behaviors-in complex networks in which cities may be linked to the resources of other cities and people may migrate in pursuit of higher welfare. We find that isolated cities (i.e., no migration) are susceptible to collapse if they do not have access to adequate resources. Links to other cities may help cities that would otherwise collapse due to insufficient resources. The effects of inter-city links, however, can vary due to the interplay between the nonlinear scaling behaviors and network structure. The long-term population level of a city is, in many settings, largely a function of the city's access to resources over which the city has little or no competition. Nonetheless, careful investigation of dynamics is required to gain mechanistic understanding of a particular city-resource network because cities and resources may collapse and the scaling behaviors may influence the effects of inter-city links, thereby distorting what topological metrics really measure.

  19. Partner network communities – a resource of universities’ activities

    Directory of Open Access Journals (Sweden)

    Romm Mark V.

    2016-01-01

    Full Text Available The network activity is not only part and parcel of the modern university, but it also demonstrates the level of its success. There appeared an urgent need for understanding the nature of universities’ network interactions and finding the most effective models of their network cooperation. The article analyzes partnership network communities with higher educational establishments (universities’ participation, which are being actively created nowadays. The conditions for successful network activities of a university in scientific, academic and professional network communities are presented.

  20. 76 FR 22721 - Notice of Availability of Draft Resource Management Plans and Associated Environmental Impact...

    Science.gov (United States)

    2011-04-22

    ... Bureau of Land Management Notice of Availability of Draft Resource Management Plans and Associated Environmental Impact Statement for the Bighorn Basin Resource Management Plan Revision Project, Cody and Worland...) has prepared a Draft Resource Management Plan (RMP) for the Cody Field Office, a Draft RMP for the...

  1. 78 FR 39010 - Notice of Availability of the Draft Resource Management Plan and Associated Environmental Impact...

    Science.gov (United States)

    2013-06-28

    ... Bureau of Land Management Notice of Availability of the Draft Resource Management Plan and Associated Environmental Impact Statement for the Buffalo Resource Management Plan Revision, Buffalo Field Office, WY... Management Act (FLPMA) of 1976, as amended, the Bureau of Land Management (BLM) has prepared a Draft Resource...

  2. 78 FR 29153 - Notice of Availability of the Draft Resource Management Plan and Environmental Impact Statement...

    Science.gov (United States)

    2013-05-17

    ... Bureau of Land Management Notice of Availability of the Draft Resource Management Plan and Environmental..., the Bureau of Land Management (BLM) has prepared a Draft Resource Management Plan (RMP) and Draft... emphasizes active management for biological restoration and cultural resource protection. The BLM would set...

  3. 75 FR 49514 - Notice of Availability for the Little Snake Proposed Resource Management Plan and Final...

    Science.gov (United States)

    2010-08-13

    ... Bureau of Land Management Notice of Availability for the Little Snake Proposed Resource Management Plan... Proposed Resource Management Plan (RMP)/Final Environmental Impact Statement (EIS) for the Little Snake... Visual Resource Management Class II, and designated as a right-of-way exclusion area unless associated...

  4. 78 FR 54909 - Notice of Availability of the Proposed Winnemucca District Resource Management Plan and Final...

    Science.gov (United States)

    2013-09-06

    ...: 14X5017] Notice of Availability of the Proposed Winnemucca District Resource Management Plan and Final... prepared a Proposed Resource Management Plan (RMP)/Final Environmental Impact Statement (EIS) for the... received on the Draft Resource Management Plan/Draft Environmental Impact Statement. The Winnemucca...

  5. 75 FR 30426 - Notice of Availability of Record of Decision for the Kemmerer Resource Management Plan...

    Science.gov (United States)

    2010-06-01

    ... Bureau of Land Management Notice of Availability of Record of Decision for the Kemmerer Resource... (ROD)/Approved Resource Management Plan (RMP) for the Kemmerer Field Office planning area located in..., objectives, and management actions to meet desired resource conditions; identifies comprehensive management...

  6. 75 FR 57056 - Notice of Availability of the Draft Buffalo Resource Management Plan Amendment for the...

    Science.gov (United States)

    2010-09-17

    ... Bureau of Land Management Notice of Availability of the Draft Buffalo Resource Management Plan Amendment... Bureau of Land Management (BLM) has prepared a Draft Resource Management Plan Amendment and Environmental... comment period. The RMPA/EA will amend the 1985 Buffalo Resource Management Plan. The BLM also announces...

  7. 76 FR 59155 - Notice of Availability of South Coast Draft Resource Management Plan Revision and Draft...

    Science.gov (United States)

    2011-09-23

    ... Bureau of Land Management Notice of Availability of South Coast Draft Resource Management Plan Revision... (BLM) has prepared a Draft Resource Management Plan (RMP) and Draft Environmental Impact Statement (EIS... demands on the resources of the public lands; changing policies and emphasis on the management of public...

  8. 77 FR 11154 - Notice of Availability for the Eastern Interior Draft Resource Management Plan/Environmental...

    Science.gov (United States)

    2012-02-24

    ... Bureau of Land Management Notice of Availability for the Eastern Interior Draft Resource Management Plan... prepared a Draft Resource Management Plan (RMP) and Environmental Impact Statement (EIS) for the Eastern... management concerns in consideration of all resource values and programs. Pursuant to 43 CFR 1610.7-2, areas...

  9. 78 FR 69705 - Notice of Availability of the Draft Resource Management Plan Amendment and Environmental...

    Science.gov (United States)

    2013-11-20

    ... Bureau of Land Management Notice of Availability of the Draft Resource Management Plan Amendment and Environmental Assessment for the San Luis Resource Area, CO AGENCY: Bureau of Land Management, Interior. ACTION... (BLM) San Luis Valley Field Office prepared a Draft Resource Management Plan Amendment (RMPA) with an...

  10. 77 FR 74508 - Notice of Availability of the Draft Resource Management Plan Amendment, Draft Environmental...

    Science.gov (United States)

    2012-12-14

    ... Bureau of Land Management Notice of Availability of the Draft Resource Management Plan Amendment, Draft Environmental Impact Statement for the Ring of Fire Resource Management Plan--Haines Planning Area, Alaska... Management Act of 1976, as amended, the Bureau of Land Management (BLM) has prepared a Draft Resource...

  11. 76 FR 55939 - Notice of Availability of the Draft Resource Management Plan and Associated Environmental Impact...

    Science.gov (United States)

    2011-09-09

    ... Bureau of Land Management Notice of Availability of the Draft Resource Management Plan and Associated Environmental Impact Statement for the Lander Resource Management Plan Revision Project, Lander Field Office... Draft Resource Management Plan (RMP) and Draft Environmental Impact Statement (EIS) for the Lander Field...

  12. 76 FR 75556 - Notice of Availability of the Proposed Resource Management Plan and Final Environmental Impact...

    Science.gov (United States)

    2011-12-02

    ... Bureau of Land Management Notice of Availability of the Proposed Resource Management Plan and Final... of Land Management (BLM) has prepared the Proposed Resource Management Plan/Final Environmental... natural resource values. The proposed plan would also apply protective management to approximately 67,032...

  13. Public health facility resource availability and provider adherence to first antenatal guidelines in a low resource setting in Accra, Ghana

    NARCIS (Netherlands)

    Amoakoh-Coleman, Mary; Agyepong, Irene Akua; Kayode, Gbenga A; Grobbee, Diederick E; Klipstein-Grobusch, Kerstin; Ansah, Evelyn K

    2016-01-01

    BACKGROUND: Lack of resources has been identified as a reason for non-adherence to clinical guidelines. Our aim was to describe public health facility resource availability in relation to provider adherence to first antenatal visit guidelines. METHODS: A cross-sectional analysis of the baseline data

  14. Resource Discovery in Activity-Based Sensor Networks

    DEFF Research Database (Denmark)

    Bucur, Doina; Bardram, Jakob

    This paper proposes a service discovery protocol for sensor networks that is specifically tailored for use in humancentered pervasive environments. It uses the high-level concept of computational activities (as logical bundles of data and resources) to give sensors in Activity-Based Sensor Networks...... (ABSNs) knowledge about their usage even at the network layer. ABSN redesigns classical network-level service discovery protocols to include and use this logical structuring of the network for a more practically applicable service discovery scheme. Noting that in practical settings activity-based sensor...... patches are localized, ABSN designs a completely distributed, hybrid discovery protocol which is proactive in a neighbourhood zone and reactive outside, tailored so that any query among the sensors of one activity is routed through the network with minimum overhead, guided by the bounds of that activity...

  15. Resource management for heterogeneous networks in LTE systems

    CERN Document Server

    Hu, Rose Qingyang

    2014-01-01

    This SpringerBrief provides an in-depth look at the key issues that affect the performance of heterogeneous networks and presents schemes that can effectively tackle these issues. In particular, this book discusses unbalanced traffic load among the macro and micro Base Stations (BSs) caused by the transmit power disparity, and a load-balancing based mobile association scheme to balance the traffic load among the macro and micro BSs. This book also introduces a fractional frequency reuse (FFR) scheme with proper power control to help reduce interference at the UEs which are most vulnerable to such intra-cell interference. The last section investigates radio resource allocation issues for heterogeneous networks with cooperative relays, and proposes a resource allocation framework that could achieve proportional fairness among the UEs. Numerical results are provided to demonstrate the effectiveness of the proposed solutions in tackling the problem and improving network performance. Resource Management for Hetero...

  16. Control of Resources for Economic Development in Food Networks

    DEFF Research Database (Denmark)

    Brink, Tove

    2010-01-01

    of preferences on the control of resources, the significant benefit of oral instructions and the significant negative impact from supervising product quality on economic development in the context of the food networking SMEs. Previous level of knowledge has no significant influence on their economic development...... to control resources for innovation to add value and economic development. This paper reveals how crossing dynamic composite underlying boundaries can have an impact on control of resources for economic development in food networking SMEs .The analyses in this paper shows the broad and significant impact......The challenge of economic development in the 21st century is linked to innovation. Enabling innovation contains a wide span from the new idea to learning how to provide value through the new idea and continuing to how to control resources to perform at prime. The focus in this paper is set on how...

  17. Particle Swarm Optimization for Adaptive Resource Allocation in Communication Networks

    Directory of Open Access Journals (Sweden)

    Gheitanchi Shahin

    2010-01-01

    Full Text Available A generalized model of particle swarm optimization (PSO technique is proposed as a low complexity method for adaptive centralized and distributed resource allocation in communication networks. The proposed model is applied to adaptive multicarrier cooperative communications (MCCC technique which utilizes the subcarriers in deep fade using a relay node in order to improve the bandwidth efficiency. Centralized PSO, based on virtual particles (VPs, is introduced for single layer and cross-layer subcarrier allocation to improve the bit error rate performance in multipath frequency selective fading channels. In the single layer strategy, the subcarriers are allocated based on the channel gains. In the cross-layer strategy, the subcarriers are allocated based on a joint measure of channel gains and distance provided by the physical layer and network layer to mitigate the effect of path loss. The concept of training particles in distributed PSO is proposed and then is applied for relay node selection. The computational complexity and traffic of the proposed techniques are investigated, and it is shown that using PSO for subcarrier allocation has a lower complexity than the techniques in the literature. Significant reduction in the traffic overhead of PSO is demonstrated when using trained particles in distributed optimizations.

  18. Maximum Interconnectedness and Availability for Directional Airborne Range Extension Networks

    Science.gov (United States)

    2016-08-29

    affecting the design and management of the network topology [2][3]. In particular, such blockages can cause significant periods of unavailability of the...a standard definition in graph theoretic and networking literature that is related to, but different from, the metric we consider. August 29, 2016...of their flightpaths are assumed to be small compared to the distance between the aircraft. A representative node layout is illustrated in Fig. 5

  19. Why do forest products become less available?A pan-tropical comparison of drivers of forest-resource degradation

    Science.gov (United States)

    Hermans-Neumann, Kathleen; Gerstner, Katharina; Geijzendorffer, Ilse R.; Herold, Martin; Seppelt, Ralf; Wunder, Sven

    2016-12-01

    Forest products provide an important source of income and wellbeing for rural smallholder communities across the tropics. Although tropical forest products frequently become over-exploited, only few studies explicitly address the dynamics of degradation in response to socio-economic drivers. Our study addresses this gap by analyzing the factors driving changes in tropical forest products in the perception of rural smallholder communities. Using the poverty and environment network global dataset, we studied recently perceived trends of forest product availability considering firewood, charcoal, timber, food, medicine, forage and other forest products. We looked at a pan-tropical sample of 233 villages with forest access. Our results show that 90% of the villages experienced declining availability of forest resources over the last five years according to the informants. Timber and fuelwood together with forest foods were featured as the most strongly affected, though with marked differences across continents. In contrast, availability of at least one main forest product was perceived to increase in only 39% of the villages. Furthermore, the growing local use of forest resources is seen as the main culprit for the decline. In villages with both growing forest resource use and immigration—vividly illustrating demographic pressures—the strongest forest resources degradation was observed. Conversely, villages with little or no population growth and a decreased use of forest resources were most likely to see significant forest-resource increases. Further, villages are less likely to perceive resource declines when local communities own a significant share of forest area. Our results thus suggest that perceived resource declines have only exceptionally triggered adaptations in local resource-use and management patterns that would effectively deal with scarcity. Hence, at the margin this supports neo-Malthusian over neo-Boserupian explanations of local resource

  20. A versatile and interoperable network sensors for water resources monitoring

    Science.gov (United States)

    Ortolani, Alberto; Brandini, Carlo; Costantini, Roberto; Costanza, Letizia; Innocenti, Lucia; Sabatini, Francesco; Gozzini, Bernardo

    2010-05-01

    Monitoring systems to assess water resources quantity and quality require extensive use of in-situ measurements, that have great limitations like difficulties to access and share data, and to customise and easy reconfigure sensors network to fulfil end-users needs during monitoring or crisis phases. In order to address such limitations Sensor Web Enablement technologies for sensors management have been developed and applied to different environmental context under the EU-funded OSIRIS project (Open architecture for Smart and Interoperable networks in Risk management based on In-situ Sensors, www.osiris-fp6.eu). The main objective of OSIRIS was to create a monitoring system to manage different environmental crisis situations, through an efficient data processing chain where in-situ sensors are connected via an intelligent and versatile network infrastructure (based on web technologies) that enables end-users to remotely access multi-domain sensors information. Among the project application, one was focused on underground fresh-water monitoring and management. With this aim a monitoring system to continuously and automatically check water quality and quantity has been designed and built in a pilot test, identified as a portion of the Amiata aquifer feeding the Santa Fiora springs (Grosseto, Italy). This aquifer present some characteristics that make it greatly vulnerable under some conditions. It is a volcanic aquifer with a fractured structure. The volcanic nature in Santa Fiora causes levels of arsenic concentrations that normally are very close to the threshold stated by law, but that sometimes overpass such threshold for reasons still not fully understood. The presence of fractures makes the infiltration rate very inhomogeneous from place to place and very high in correspondence of big fractures. In case of liquid-pollutant spills (typically hydrocarbons spills from tanker accidents or leakage from house tanks containing fuel for heating), these fractures can act

  1. Wind Resource Assessment and Forecast Planning with Neural Networks

    Directory of Open Access Journals (Sweden)

    Nicolus K. Rotich

    2014-06-01

    Full Text Available In this paper we built three types of artificial neural networks, namely: Feed forward networks, Elman networks and Cascade forward networks, for forecasting wind speeds and directions. A similar network topology was used for all the forecast horizons, regardless of the model type. All the models were then trained with real data of collected wind speeds and directions over a period of two years in the municipal of Puumala, Finland. Up to 70th percentile of the data was used for training, validation and testing, while 71–85th percentile was presented to the trained models for validation. The model outputs were then compared to the last 15% of the original data, by measuring the statistical errors between them. The feed forward networks returned the lowest errors for wind speeds. Cascade forward networks gave the lowest errors for wind directions; Elman networks returned the lowest errors when used for short term forecasting.

  2. Influence of dietary specialization and resource availability on geographical variation in abundance of butterflyfish.

    Science.gov (United States)

    Lawton, Rebecca J; Pratchett, Morgan S

    2012-07-01

    Empirical evidence indicates that both niche breadth and resource availability are key drivers of a species' local abundance patterns. However, most studies have considered the influence of either niche breath or resource availability in isolation, while it is the interactive effects that are likely to influence local abundance. We examined geographic variation in the feeding ecology and distribution of coral-feeding butterflyfish to determine the influence of dietary specialization and dietary resource availability on their local abundance. Dietary composition and abundance of five butterflyfish and coral dietary resource availability were determined at 45 sites across five locations (Lizard Island and Heron Island, Great Barrier Reef; Kimbe Bay, Papua New Guinea; Noumea, New Caledonia; and Moorea, French Polynesia). Multiple regression models using variables representative of total dietary resource availability, availability of specific dietary resources, and interspecific competition were used to determine the best predictors of local abundance across all sites and locations for each species. Factors influencing local abundance varied between butterflyfish with specialized and generalized diets. Dietary resource availability had the strongest influence on the abundance of Chaetodon trifascialis-the most specialized species. Local abundance of C. trifascialis was best predicted by availability of the Acropora corals that it preferentially feeds on. In contrast, abundance of generalist butterflyfish was poorly described by variation in availability of specific resources. Rather, indices of total dietary resource availability best predicted their abundance. Overall, multiple regression models only explained a small proportion of the variation in local abundance for all five species. Despite their relatively specialized diets, dietary resource availability has limited influence on the local abundance of butterflyfish. Only the most specialized species appear to be

  3. Uncertainty in the availability of natural resources: Fossil fuels, critical metals and biomass

    OpenAIRE

    Speirs, Jamie; McGlade, Christophe; Slade, Raphael

    2015-01-01

    Energy policies are strongly influenced by resource availability and recoverability estimates. Yet these estimates are often highly uncertain, frequently incommensurable, and regularly contested. This paper explores how the uncertainties surrounding estimates of the availability of fossil fuels, biomass and critical metals are conceptualised and communicated. The contention is that a better understanding of the uncertainties surrounding resource estimates for both conventional and renewable e...

  4. 77 FR 35999 - Notice of Availability of the Proposed Resource Management Plan/Final Environmental Impact...

    Science.gov (United States)

    2012-06-15

    ... Bureau of Land Management Notice of Availability of the Proposed Resource Management Plan/ Final... Act of 1976, as amended, the Bureau of Land Management (BLM) has prepared a Proposed Resource...: Bureau of Land Management, Interior. ACTION: Notice of Availability. SUMMARY: In accordance with the...

  5. Adaptive workflow scheduling in grid computing based on dynamic resource availability

    Directory of Open Access Journals (Sweden)

    Ritu Garg

    2015-06-01

    Full Text Available Grid computing enables large-scale resource sharing and collaboration for solving advanced science and engineering applications. Central to the grid computing is the scheduling of application tasks to the resources. Various strategies have been proposed, including static and dynamic strategies. The former schedules the tasks to resources before the actual execution time and later schedules them at the time of execution. Static scheduling performs better but it is not suitable for dynamic grid environment. The lack of dedicated resources and variations in their availability at run time has made this scheduling a great challenge. In this study, we proposed the adaptive approach to schedule workflow tasks (dependent tasks to the dynamic grid resources based on rescheduling method. It deals with the heterogeneous dynamic grid environment, where the availability of computing nodes and links bandwidth fluctuations are inevitable due to existence of local load or load by other users. The proposed adaptive workflow scheduling (AWS approach involves initial static scheduling, resource monitoring and rescheduling with the aim to achieve the minimum execution time for workflow application. The approach differs from other techniques in literature as it considers the changes in resources (hosts and links availability and considers the impact of existing load over the grid resources. The simulation results using randomly generated task graphs and task graphs corresponding to real world problems (GE and FFT demonstrates that the proposed algorithm is able to deal with fluctuations of resource availability and provides overall optimal performance.

  6. Resource availability as driving factor of the reproductive mode in soil microarthropods (Acari, Oribatida.

    Directory of Open Access Journals (Sweden)

    Katja Wehner

    Full Text Available The availability of high quality resources is an important factor driving community structure and reproductive mode of animals. Parthenogenetic reproduction prevails when resources are available in excess, whereas sexuality correlates with resource shortage. We investigated the effect of resource availability on the community structure of oribatid mites in a laboratory experiment. Availability of food resources was increased by addition of glucose to leaf litter and reduced by leaching of nutrients from leaf litter. Experimental systems were incubated at three different temperatures to establish different regimes of resource exploitation. Community structure of oribatids and numbers of eggs per female were measured over a period of ten months. We expected the density of oribatid mites to decline in the reduced litter quality treatment but to increase in the glucose treatment. Both effects were assumed to be more pronounced at higher temperatures. We hypothesized sexual species to be less affected than parthenogenetic species by reduced resource quality due to higher genetic diversity allowing more efficient exploitation of limited resources, but to be outnumbered by parthenogenetic species in case of resource addition due to faster reproduction. In contrast to our hypotheses, both sexual and parthenogenetic oribatid mite species responded similarly with their densities declining uniformly during incubation. The parthenogenetic Brachychthoniidae and Tectocepheus dominated early in the experiment but were replaced later by parthenogenetic Desmonomata and Rhysotritia. In parthenogenetic species the number of eggs per female increased during the experiment while the number of eggs in sexual females remained constant or decreased slightly; in general, egg numbers were higher in sexual than in parthenogenetic species. The results indicate that for sustaining oribatid mite populations other resources than litter and associated saprotrophic

  7. Pricing resources in LTE networks through multiobjective optimization.

    Science.gov (United States)

    Lai, Yung-Liang; Jiang, Jehn-Ruey

    2014-01-01

    The LTE technology offers versatile mobile services that use different numbers of resources. This enables operators to provide subscribers or users with differential quality of service (QoS) to boost their satisfaction. On one hand, LTE operators need to price the resources high for maximizing their profits. On the other hand, pricing also needs to consider user satisfaction with allocated resources and prices to avoid "user churn," which means subscribers will unsubscribe services due to dissatisfaction with allocated resources or prices. In this paper, we study the pricing resources with profits and satisfaction optimization (PRPSO) problem in the LTE networks, considering the operator profit and subscribers' satisfaction at the same time. The problem is modelled as nonlinear multiobjective optimization with two optimal objectives: (1) maximizing operator profit and (2) maximizing user satisfaction. We propose to solve the problem based on the framework of the NSGA-II. Simulations are conducted for evaluating the proposed solution.

  8. Resource Management in QoS-Aware Wireless Cellular Networks

    Science.gov (United States)

    Zhang, Zhi

    2011-01-01

    Emerging broadband wireless networks that support high speed packet data with heterogeneous quality of service (QoS) requirements demand more flexible and efficient use of the scarce spectral resource. Opportunistic scheduling exploits the time-varying, location-dependent channel conditions to achieve multiuser diversity. In this work, we study…

  9. Radio Resource sharing in a GSM/GPRS network

    NARCIS (Netherlands)

    Litjens, R.; Boucherie, R.J.

    2000-01-01

    An extensive performance evaluation is presented for a segregated and a hybrid radio resource sharing scheme in an integrated GSM/GPRS network, with a finite queue for data calls that cannot be served immediately upon arrival. Markov chain analysis is used to derive simple performance measures such

  10. Statistical model of global uranium resources and long-term availability

    Directory of Open Access Journals (Sweden)

    Monnet Antoine

    2016-01-01

    Full Text Available Most recent studies on the long-term supply of uranium make simplistic assumptions on the available resources and their production costs. Some consider the whole uranium quantities in the Earth's crust and then estimate the production costs based on the ore grade only, disregarding the size of ore bodies and the mining techniques. Other studies consider the resources reported by countries for a given cost category, disregarding undiscovered or unreported quantities. In both cases, the resource estimations are sorted following a cost merit order. In this paper, we describe a methodology based on “geological environments”. It provides a more detailed resource estimation and it is more flexible regarding cost modelling. The global uranium resource estimation introduced in this paper results from the sum of independent resource estimations from different geological environments. A geological environment is defined by its own geographical boundaries, resource dispersion (average grade and size of ore bodies and their variance, and cost function. With this definition, uranium resources are considered within ore bodies. The deposit breakdown of resources is modelled using a bivariate statistical approach where size and grade are the two random variables. This makes resource estimates possible for individual projects. Adding up all geological environments provides a repartition of all Earth's crust resources in which ore bodies are sorted by size and grade. This subset-based estimation is convenient to model specific cost structures.

  11. Decomposition method for zonal resource allocation problems in telecommunication networks

    Science.gov (United States)

    Konnov, I. V.; Kashuba, A. Yu

    2016-11-01

    We consider problems of optimal resource allocation in telecommunication networks. We first give an optimization formulation for the case where the network manager aims to distribute some homogeneous resource (bandwidth) among users of one region with quadratic charge and fee functions and present simple and efficient solution methods. Next, we consider a more general problem for a provider of a wireless communication network divided into zones (clusters) with common capacity constraints. We obtain a convex quadratic optimization problem involving capacity and balance constraints. By using the dual Lagrangian method with respect to the capacity constraint, we suggest to reduce the initial problem to a single-dimensional optimization problem, but calculation of the cost function value leads to independent solution of zonal problems, which coincide with the above single region problem. Some results of computational experiments confirm the applicability of the new methods.

  12. Resource Availability as Driving Factor of the Reproductive Mode in Soil Microarthropods (Acari, Oribatida)

    Science.gov (United States)

    Wehner, Katja; Scheu, Stefan; Maraun, Mark

    2014-01-01

    The availability of high quality resources is an important factor driving community structure and reproductive mode of animals. Parthenogenetic reproduction prevails when resources are available in excess, whereas sexuality correlates with resource shortage. We investigated the effect of resource availability on the community structure of oribatid mites in a laboratory experiment. Availability of food resources was increased by addition of glucose to leaf litter and reduced by leaching of nutrients from leaf litter. Experimental systems were incubated at three different temperatures to establish different regimes of resource exploitation. Community structure of oribatids and numbers of eggs per female were measured over a period of ten months. We expected the density of oribatid mites to decline in the reduced litter quality treatment but to increase in the glucose treatment. Both effects were assumed to be more pronounced at higher temperatures. We hypothesized sexual species to be less affected than parthenogenetic species by reduced resource quality due to higher genetic diversity allowing more efficient exploitation of limited resources, but to be outnumbered by parthenogenetic species in case of resource addition due to faster reproduction. In contrast to our hypotheses, both sexual and parthenogenetic oribatid mite species responded similarly with their densities declining uniformly during incubation. The parthenogenetic Brachychthoniidae and Tectocepheus dominated early in the experiment but were replaced later by parthenogenetic Desmonomata and Rhysotritia. In parthenogenetic species the number of eggs per female increased during the experiment while the number of eggs in sexual females remained constant or decreased slightly; in general, egg numbers were higher in sexual than in parthenogenetic species. The results indicate that for sustaining oribatid mite populations other resources than litter and associated saprotrophic microorganisms are needed. They

  13. Resource availability and competition shape the evolution of survival and growth ability in a bacterial community.

    Directory of Open Access Journals (Sweden)

    Minna Pekkonen

    Full Text Available Resource availability is one of the main factors determining the ecological dynamics of populations or species. Fluctuations in resource availability can increase or decrease the intensity of resource competition. Resource availability and competition can also cause evolutionary changes in life-history traits. We studied how community structure and resource fluctuations affect the evolution of fitness related traits using a two-species bacterial model system. Replicated populations of Serratia marcescens (copiotroph and Novosphingobium capsulatum (oligotroph were reared alone or together in environments with intergenerational, pulsed resource renewal. The comparison of ancestral and evolved bacterial clones with 1 or 13 weeks history in pulsed resource environment revealed species-specific changes in life-history traits. Co-evolution with S. marcescens caused N. capsulatum clones to grow faster. The evolved S. marcescens clones had higher survival and slower growth rate then their ancestor. The survival increased in all treatments after one week, and thereafter continued to increase only in the S. marcescens monocultures that experienced large resource pulses. Though adaptive radiation is often reported in evolution studies with bacteria, clonal variation increased only in N. capsulatum growth rate. Our results suggest that S. marcescens adapted to the resource renewal cycle whereas N. capsulatum was more affected by the interspecific competition. Our results exemplify species-specific evolutionary response to both competition and environmental variation.

  14. Fair sharing of resources in a supply network with constraints.

    Science.gov (United States)

    Carvalho, Rui; Buzna, Lubos; Just, Wolfram; Helbing, Dirk; Arrowsmith, David K

    2012-04-01

    This paper investigates the effect of network topology on the fair allocation of network resources among a set of agents, an all-important issue for the efficiency of transportation networks all around us. We analyze a generic mechanism that distributes network capacity fairly among existing flow demands. The problem can be solved by semianalytical methods on a nearest-neighbor graph with one source and sink pair, when transport occurs over shortest paths. For this setup, we uncover a broad range of patterns of intersecting shortest paths as a function of the distance between the source and the sink. When the number of intersections is the maximum and the distance between the source and the sink is large, we find that a fair allocation implies a decrease of at least 50% from the maximum throughput. We also find that the histogram of the flow allocations assigned to the agents decays as a power law with exponent -1. Our semianalytical framework suggests possible explanations for the well-known reduction of the throughput in fair allocations. It also suggests that the combination of network topology and routing rules can lead to highly uneven (but fair) distributions of resources, a remark of caution to network designers.

  15. Scheduled Controller Design of Congestion Control Considering Network Resource Constraints

    Science.gov (United States)

    Naito, Hiroyuki; Azuma, Takehito; Fujita, Masayuki

    In this paper, we consider a dynamical model of computer networks and derive a synthesis method for congestion control. First, we show a model of TCP/AQM (Transmission Control Protocol/Active Queue Management) as a dynamical model of computer networks. The dynamical model of TCP/AQM networks consists of models of TCP window size, queue length and AQM mechanisms. Second, we propose to describe the dynamical model of TCP/AQM networks as linear systems with self-scheduling parameters, which also depend on information delay. Here we focus on the constraints on the maximum queue length and TCP window-size, which are the network resources in TCP/AQM networks. We derive TCP/AQM networks as the LPV system (linear parameter varying system) with information delay and self-scheduling parameter. We design a memoryless state feedback controller of the LPV system based on a gain-scheduling method. Finally, the effectiveness of the proposed method is evaluated by using MATLAB and the well-known ns-2 (Network Simulator Ver.2) simulator.

  16. SeaDataNet network services monitoring: Definition and Implementation of Service availability index

    Science.gov (United States)

    Lykiardopoulos, Angelos; Mpalopoulou, Stavroula; Vavilis, Panagiotis; Pantazi, Maria; Iona, Sissy

    2014-05-01

    SeaDataNet (SDN) is a standardized system for managing large and diverse data sets collected by the oceanographic fleets and the automatic observation systems. The SeaDataNet network is constituted of national oceanographic data centres of 35 countries, active in data collection. SeaDataNetII project's objective is to upgrade the present SeaDataNet infrastructure into an operationally robust and state-of-the-art infrastructure; therefore Network Monitoring is a step to this direction. The term Network Monitoring describes the use of system that constantly monitors a computer network for slow or failing components and that notifies the network administrator in case of outages. Network monitoring is crucial when implementing widely distributed systems over the Internet and in real-time systems as it detects malfunctions that may occur and notifies the system administrator who can immediately respond and correct the problem. In the framework of SeaDataNet II project a monitoring system was developed in order to monitor the SeaDataNet components. The core system is based on Nagios software. Some plug-ins were developed to support SeaDataNet modules. On the top of Nagios Engine a web portal was developed in order to give access to local administrators of SeaDataNet components, to view detailed logs of their own service(s). Currently the system monitors 35 SeaDataNet Download Managers, 9 SeaDataNet Services, 25 GeoSeas Download Managers and 23 UBSS Download Managers . Taking advantage of the continuous monitoring of SeaDataNet system components a total availability index will be implemented. The term availability can be defined as the ability of a functional unit to be in a state to perform a required function under given conditions at a given instant of time or over a given time interval, assuming that the required external resources are provided. Availability measures can be considered as a are very important benefit becauseT - The availability trends that can be

  17. Electricity Networks: Infrastructure and Operations. Too complex for a resource?

    Energy Technology Data Exchange (ETDEWEB)

    Volk, Dennis

    2013-07-01

    Electricity security remains a priority of energy policy and continuous electrification will further enhance the importance in the years to come. Market liberalisation has brought substantial benefits to societies, including competition, innovation, more client-oriented services and the reduced needs for public expenditure. Further, the path of decarbonisation is a must but experiences with many new technologies and policies show their many implications on power systems. Electricity networks form the backbone of reliable and affordable power systems and also significantly support the inception of renewable generation. The importance of distribution and transmission networks has to be well understood by policy makers and regulators to maintain the sensitive balance within the policy triangle of reliability, affordability and sustainability as power systems rapidly change. Failures in choosing the right institutions and regulatory frameworks to operate and build networks will put the sensitive balance within the policy triangle at risk. ''Too complex for a resource?'' identifies the key challenges the electricity distribution and transmission networks face today and in the future. It further provides for best practice examples on institutional design choices and regulatory frameworks for sound network service provision but also highlights the importance of additional responses required. More market-based and dynamic frameworks for various system services, the growing need for active service participation of renewable generators and highly independent and transparent central operators seem to be at the heart of these responses. ''Too complex for a resource?'' finds that the answer to the challenges ahead is not always more infrastructure and that networks and the services they provide have to be regarded as equal part of the total power system. Thus, accurate and dynamic cost allocation can significantly support to transform

  18. Resource availability modulates biodiversity-invasion relationships by altering competitive interactions

    OpenAIRE

    Yang, Tianjie; Wei, Zhong; Friman, Ville-Petri; Xu, Yangchun; Shen, Qirong; Kowalchuk, George; Jousset, Alexandre

    2017-01-01

    Community diversity affects the survival of newly introduced species via resource competition. Competitive interactions can be modulated by resource availability and we hypothesized that this may alter biodiversity-invasion relationships. To study this, we assessed the growth of a bacterial invader, Ralstonia solanacearum, when introduced into communities comprised of one to five closely related resident species under different resource concentrations. The invader growth was then examined as ...

  19. The NEON Aquatic Network: Expanding the Availability of Biogeochemical Data

    Science.gov (United States)

    Vance, J. M.; Bohall, C.; Fitzgerald, M.; Utz, R.; Parker, S. M.; Roehm, C. L.; Goodman, K. J.; McLaughlin, B.

    2013-12-01

    Aquatic ecosystems are facing unprecedented pressure from climate change and land-use practices. Invasive species, whether plant, animal, insect or microbe present additional threat to aquatic ecosystem services. There are significant scientific challenges to understanding how these forces will interact to affect aquatic ecosystems, as the flow of energy and materials in the environment is driven by multivariate and non-linear biogeochemical cycles. The National Ecological Observatory Network (NEON) will collect and provide observational data across multiple scales. Sites were selected to maximize representation of major North American ecosystems using a multivariate geographic clustering method that partitioned the continental US, AK, HI, and Puerto Rico into 20 eco-climatic domains. The NEON data collection systems and methods are designed to yield standardized, near real-time data subjected to rigorous quality controls prior to public dissemination through an online data portal. NEON will collect data for 30 years to facilitate spatial-temporal analysis of environmental responses and drivers of ecosystem change, ranging from local through continental scales. Here we present the NEON Aquatic Network, a multi-parameter network consisting of a combination of in situ sensor and observational data. This network will provide data to examine biogeochemical, biological, hydrologic and geomorphic metrics at 36 sites, which are a combination of small 1st/2nd order wadeable streams, large rivers and lakes. A typical NEON Aquatic site will host up to two in-stream sensor sets designed to collect near-continuous water quality data (e.g. pH/ORP, temperature, conductivity, dissolved oxygen, CDOM) along with up to 8 shallow groundwater monitoring wells (level, temp., cond.), and a local meteorological station (e.g. 2D wind speed, PAR, barometric pressure, temperature, net radiation). These coupled sensor suites will be complemented by observational data (e.g. water

  20. Measuring changes in consumer resource availability to riverine pulsing in Breton Sound, Louisiana, USA.

    Directory of Open Access Journals (Sweden)

    Bryan P Piazza

    Full Text Available Resource pulses are thought to structure communities and food webs through the assembly of consumers. Aggregated consumers represent a high quality resource subsidy that becomes available for trophic transfer during and after the pulse. In estuarine systems, riverine flood pulses deliver large quantities of basal resources and make high quality habitat available for exploitation by consumers. These consumers represent a change in resources that may be available for trophic transfer. We quantified this increased consumer resource availability (nekton density, biomass, energy density provided by riverine flood pulsing in Breton Sound, Louisiana, USA. We used water level differences between an area subject to two experimental riverine flood pulses (inflow and a reference area not receiving inflow to identify the percentage of nekton standing stock and energy density that may be attributable solely to riverine pulsing and may represent a consumer resource subsidy. Riverine pulsing accounted for more than 60% of resident nekton density (ind m(-2, biomass (g m(-2, and energy density (cal m(-2 on the flooded marsh surface during two experimental pulse events in 2005. Our results document the potential subsidy of resident nekton standing stock from a riverine flood pulse available for export to subtidal habitats. Given predicted large scale changes in river discharge globally, this approach could provide a useful tool for quantifying the effects of changes in riverine discharge on consumer resource availability.

  1. Network Monitoring and Diagnosis Based on Available Bandwidth Measurement

    Science.gov (United States)

    2006-05-01

    encouragements helped me pass those tough early days in the US. I would also like to thank my officemates Julio Lopez and Rajesh Balan, both system experts. With...tradeoffs of structured overlays in a dynamic non-transitive network. In MIT 6.829 Fall 2003 class project, December 2003. [52] Ramesh Govindan and Vern ...using packet quartets. In ACM SIGCOMM Internet Measurement Workshop 2002, 2002. [92] Vern Paxson. Measurements and Analysis of End-to-End Internet

  2. Reliability, Availability and Serviceability of Networks-on-Chip

    CERN Document Server

    Cota, Érika; Soares Lubaszewski, Marcelo

    2012-01-01

    This book presents an overview of the issues related to the test, diagnosis and fault-tolerance of Network on Chip-based systems. It is the first book dedicated to the quality aspects of NoC-based systems and will serve as an invaluable reference to the problems, challenges, solutions, and trade-offs related to designing and implementing state-of-the-art, on-chip communication architectures.

  3. Intent-based resource deployment in wireless sensor networks

    Science.gov (United States)

    de Mel, Geeth; Pham, Tien; Sullivan, Paul; Grueneberg, Keith; Vasconcelos, Wamberto; Norman, Tim

    2012-06-01

    Information derived from sensor networks plays a crucial role in the success of many critical tasks such as surveillance, and border monitoring. In order to derive the correct information at the right time, sensor data must be captured at desired locations with respect to the operational tasks in concern. Therefore, it is important that at the planning stage of a mission, sensing resources are best placed in the field to capture the required data. For example, consider a mission goal identify snipers, in an operational area before troops are deployed - two acoustic arrays and a day-night video camera are needed to successfully achieve this goal. This is because, if the resources are placed in correct locations, two acoustic arrays could provide direction of the shooter and a possible location by triangulating acoustic data whereas the day-night camera could produce an affirmative image of the perpetrators. In order to deploy the sensing resources intelligently to support the user decisions, in this paper we propose a Semantic Web based knowledge layer to identify the required resources in a sensor network and deploy the needed resources through a sensor infrastructure. The knowledge layer captures crucial information such as resources configurations, their intended use (e.g., two acoustic arrays deployed in a particular formation with day-night camera are needed to identify perpetrators in a possible sniper attack). The underlying sensor infrastructure will assists the process by exposing the information about deployed resources, resources in theatre, and location information about tasks, resources and so on.

  4. Superficial Water Resource at Tempisque River Watershed, Costa Rica: Availability and Requirement Perspective

    Directory of Open Access Journals (Sweden)

    Isabel Guzmán-Arias

    2014-03-01

    Full Text Available This paper describes the status of water resources availability and demand in the upper and middle Tempisque watershed projected up to 2030 and the proposed actions to start a planning process. The resource availability scenarios incorporate the modifications inwater flows due to land use and cli­mate changes; these combined effects increases the problems of water shortages during the dry season. The resource demand scenarios include projections provided by the major users in the watershed, of which very few can envision growth expectations in terms of water consumption. The proposed resource planning process integrates the analysis conducted in this thesis and tries to identify the basic steps to be followed for the pro­per management of the resource in the future.

  5. Measuring changes in consumer resource availability to riverine pulsing in Breton Sound, Louisiana, USA.

    Science.gov (United States)

    Piazza, Bryan P; La Peyre, Megan K

    2012-01-01

    Resource pulses are thought to structure communities and food webs through the assembly of consumers. Aggregated consumers represent a high quality resource subsidy that becomes available for trophic transfer during and after the pulse. In estuarine systems, riverine flood pulses deliver large quantities of basal resources and make high quality habitat available for exploitation by consumers. These consumers represent a change in resources that may be available for trophic transfer. We quantified this increased consumer resource availability (nekton density, biomass, energy density) provided by riverine flood pulsing in Breton Sound, Louisiana, USA. We used water level differences between an area subject to two experimental riverine flood pulses (inflow) and a reference area not receiving inflow to identify the percentage of nekton standing stock and energy density that may be attributable solely to riverine pulsing and may represent a consumer resource subsidy. Riverine pulsing accounted for more than 60% of resident nekton density (ind m(-2)), biomass (g m(-2)), and energy density (cal m(-2)) on the flooded marsh surface during two experimental pulse events in 2005. Our results document the potential subsidy of resident nekton standing stock from a riverine flood pulse available for export to subtidal habitats. Given predicted large scale changes in river discharge globally, this approach could provide a useful tool for quantifying the effects of changes in riverine discharge on consumer resource availability.

  6. Resource availability modulates biodiversity-invasion relationships by altering competitive interactions

    NARCIS (Netherlands)

    Yang, Tianjie; Wei, Zhong; Friman, Ville-Petri; Xu, Yangchun; Shen, Qirong; Kowalchuk, George; Jousset, Alexandre

    Community diversity affects the survival of newly introduced species via resource competition. Competitive interactions can be modulated by resource availability and we hypothesized that this may alter biodiversity-invasion relationships. To study this, we assessed the growth of a bacterial invader,

  7. What People Living with Aphasia Think about the Availability of Aphasia Resources

    Science.gov (United States)

    Hinckley, Jacqueline J.; Hasselkus, Amy; Ganzfried, Ellayne

    2013-01-01

    Purpose: Obtaining health information and resources can influence an individual's (a) access to services, (b) interactions with health care providers, and (c) ability to manage one's own health needs. The purpose of this study was to gather the perceptions of consumers living with aphasia about resource availability and information needs. Method:…

  8. Availability and type of human resource for health in public primary ...

    African Journals Online (AJOL)

    Background: Health human resource capacity is one of the major determinants of an effective health care delivery system. It is more importantly so in the Primary Health Care system, which is the key component of every health system. This study assessed the available and type of human resource for health in public primary ...

  9. 77 FR 52054 - Notice of Availability of the Proposed Bakersfield Resource Management Plan and Final...

    Science.gov (United States)

    2012-08-28

    ... Bureau of Land Management Notice of Availability of the Proposed Bakersfield Resource Management Plan and Final Environmental Impact Statement, California AGENCY: Bureau of Land Management. ACTION: Notice of... (BLM) has prepared the Proposed Resource Management Plan (RMP) and Final Environmental Impact Statement...

  10. 75 FR 54177 - Notice of Availability of the Draft Jarbidge Field Office Resource Management Plan and...

    Science.gov (United States)

    2010-09-03

    ...] [FR Doc No: 2010-21956] DEPARTMENT OF THE INTERIOR Bureau of Land Management [LLIDT01000.L16100000.DP0000.LXSS081D0000] Notice of Availability of the Draft Jarbidge Field Office Resource Management Plan... Management (BLM) has prepared a Draft Resource Management Plan (RMP) and Draft Environmental Impact Statement...

  11. Yoga lessons for consciousness research: a paralimbic network balancing brain resource allocation

    Directory of Open Access Journals (Sweden)

    Hans C Lou

    2011-12-01

    Full Text Available Consciousness has been proposed to play a key role in shaping flexible learning and as such is thought to confer an evolutionary advantage. Attention and awareness are the perhaps most important underlying processes, yet their precise relationship is presently unclear. Both of these processes must, however, serve the evolutionary imperatives of survival and procreation. They are thus intimately bound by reward and emotion to help to prioritize efficient brain resource allocation in order to predict and optimize behaviour. Here we show how this process is served by a paralimbic network consisting primarily of regions located on the midline of the human brain. Using many different techniques, experiments have demonstrated that this network is effective and specific for self-awareness and contributes to the sense of unity of consciousness by acting as a common neural path for a wide variety of conscious experiences. Interestingly, haemodynamic activity in the network decreases with focusing on external stimuli, which has led to the idea of a default mode network. This network is one of many networks that wax and vane as resources are allocated to accommodate the different cyclical needs of the organism primarily related the fundamental pleasures afforded by evolution: food, sex and conspecifics. Here we hypothesize, however, that the paralimbic network serves a crucial role in balancing and regulating brain resource allocation, and discuss how it can be thought of as a link between current theories of so-called default mode, resting state networks and global workspace. We show how major developmental disorders of self-awareness and self-control can arise from problems in the paralimbic network as demonstrated here by the example of Asperger syndrome. We conclude that attention, awareness and emotion are integrated by a paralimbic network that helps to efficiently allocate brain resources to optimize behaviour and help survival.

  12. Exploring dynamic mechanisms of learning networks for resource conservation

    Directory of Open Access Journals (Sweden)

    Petr Matous

    2015-06-01

    Full Text Available The importance of networks for social-ecological processes has been recognized in the literature; however, existing studies have not sufficiently addressed the dynamic nature of networks. Using data on the social learning networks of 265 farmers in Ethiopia for 2011 and 2012 and stochastic actor-oriented modeling, we explain the mechanisms of network evolution and soil conservation. The farmers' preferences for information exchange within the same social groups support the creation of interactive, clustered, nonhierarchical structures within the evolving learning networks, which contributed to the diffusion of the practice of composting. The introduced methods can be applied to determine whether and how social networks can be used to facilitate environmental interventions in various contexts.

  13. Host resistance and tolerance of parasitic gut worms depend on resource availability.

    Science.gov (United States)

    Knutie, Sarah A; Wilkinson, Christina L; Wu, Qiu Chang; Ortega, C Nicole; Rohr, Jason R

    2017-04-01

    Resource availability can significantly alter host-parasite dynamics. Abundant food can provide more resources for hosts to resist infections, but also increase host tolerance of infections by reducing competition between hosts and parasites for food. Whether abundant food favors host resistance or tolerance (or both) might depend on the type of resource that the parasite exploits (e.g., host tissue vs. food), which can vary based on the stage of infection. In our study, we evaluated how low and high resource diets affect Cuban tree frog (Osteopilus septentrionalis) resistance and tolerance of a skin-penetrating, gut nematode Aplectana sp. at each stage of the infection. Compared to a low resource diet, a high resource diet enhanced frog resistance to worm penetration and tolerance while worms traveled to the gut. In contrast, a low resource diet increased resistance to establishment of the infection. After the infection established and worms could access food resources in the gut, a high resource diet enhanced host tolerance of parasites. On a high resource diet, parasitized frogs consumed significantly more food than non-parasitized frogs; when food was then restricted, mass of non-parasitized frogs did not change, whereas mass of parasitized frogs decreased significantly. Thus, a high resource diet increased frog tolerance of established worms because frogs could fully compensate for energy lost to the parasites. Our study shows that host-parasite dynamics are influenced by the effect of resource availability on host resistance and tolerance, which depends on when parasites have access to food and the stage of infection.

  14. Scalable and Hybrid Radio Resource Management for Future Wireless Networks

    DEFF Research Database (Denmark)

    Mino, E.; Luo, Jijun; Tragos, E.

    2007-01-01

    The concept of ubiquitous and scalable system is applied in the IST WINNER II [1] project to deliver optimum performance for different deployment scenarios, from local area to wide area wireless networks. The integration in a unique radio system of a cellular and local area type networks supposes...... describes a proposal for scalable and hybrid radio resource management to efficiently integrate the different WINNER system modes. Index...... a great advantage for the final user and for the operator, compared with the current situation, with disconnected systems, usually with different subscriptions, radio interfaces and terminals. To be a ubiquitous wireless system, the IST project WINNER II has defined three system modes. This contribution...

  15. The contributions of resource availability and social forces to foraging distributions : a spatial lag modelling approach

    NARCIS (Netherlands)

    Folmer, Eelke O.; Piersma, Theunis

    2012-01-01

    The spatial distribution of foraging animals at a given time simultaneously depends on (1) exogenous environmental variables such as resource availability and abiotic habitat characteristics, and (2) the endogenous variable social aggregation made up of the opposing mechanisms of conspecific

  16. The contributions of resource availability and social forces to foraging distributions: a spatial lag modelling approach

    NARCIS (Netherlands)

    Folmer, E.O.; Piersma, T.

    2012-01-01

    The spatial distribution of foraging animals at a given time simultaneously depends on (1) exogenous environmental variables such as resource availability and abiotic habitat characteristics, and (2) the endogenous variable social aggregation made up of the opposing mechanisms of conspecific

  17. Joint Fair Resource Allocation for Opportunistic Spectrum Sharing in OFDM-based Cognitive Radio Networks

    Directory of Open Access Journals (Sweden)

    Yanbo Ma

    2015-08-01

    Full Text Available This paper considers a cooperative Orthogonal Frequency Division Multiplexing (OFDM-based cognitive radio network, where the primary system leases a fraction of its subcarriers to the secondary system in exchange for the secondary users (SUs acting as decode-and-forward relays. Our aim is to determine an fair resource allocation strategy among the primary users and SUs as so to maximize the network capacity. To this end, a network utility maximization optimization problem of power, subcarrier allocation and relay selection is formulated based on a class of α-fair utility. This problem is solved by applying the lagrangian dual method and a joint fair resource allocation policy at the SUs is derived in a closed-form expression. Moreover, a novel stochastic algorithm is developed to approach the optimal policy by dynamically learning the intended wireless channels. Simulation results demonstrate that both primary and secondary systems can benefit from the proposed resource allocation policy.

  18. Adolescents, Health Education, and Computers: The Body Awareness Resource Network (BARN).

    Science.gov (United States)

    Bosworth, Kris; And Others

    1983-01-01

    The Body Awareness Resource Network (BARN) is a computer-based system designed as a confidential, nonjudgmental source of health information for adolescents. Topics include alcohol and other drugs, diet and activity, family communication, human sexuality, smoking, and stress management; programs are available for high school and middle school…

  19. BIRI: a new approach for automatically discovering and indexing available public bioinformatics resources from the literature.

    Science.gov (United States)

    de la Calle, Guillermo; García-Remesal, Miguel; Chiesa, Stefano; de la Iglesia, Diana; Maojo, Victor

    2009-10-07

    The rapid evolution of Internet technologies and the collaborative approaches that dominate the field have stimulated the development of numerous bioinformatics resources. To address this new framework, several initiatives have tried to organize these services and resources. In this paper, we present the BioInformatics Resource Inventory (BIRI), a new approach for automatically discovering and indexing available public bioinformatics resources using information extracted from the scientific literature. The index generated can be automatically updated by adding additional manuscripts describing new resources. We have developed web services and applications to test and validate our approach. It has not been designed to replace current indexes but to extend their capabilities with richer functionalities. We developed a web service to provide a set of high-level query primitives to access the index. The web service can be used by third-party web services or web-based applications. To test the web service, we created a pilot web application to access a preliminary knowledge base of resources. We tested our tool using an initial set of 400 abstracts. Almost 90% of the resources described in the abstracts were correctly classified. More than 500 descriptions of functionalities were extracted. These experiments suggest the feasibility of our approach for automatically discovering and indexing current and future bioinformatics resources. Given the domain-independent characteristics of this tool, it is currently being applied by the authors in other areas, such as medical nanoinformatics. BIRI is available at http://edelman.dia.fi.upm.es/biri/.

  20. The Resource Mapping Algorithm of Wireless Virtualized Networks for Saving Energy in Ultradense Small Cells

    Directory of Open Access Journals (Sweden)

    Sai Zou

    2015-01-01

    Full Text Available As the current network is designed for peak loads, it results in insufficient resource utilization and energy waste. Virtualized technology makes it possible that intelligent energy perception network could be deployed and resource sharing could become an effective energy saving technology. How to make more small cells into sleeping state for energy saving in ultradense small cell system has become a research hot spot. Based on the mapping feature of virtualized network, a new wireless resource mapping algorithm for saving energy in ultradense small cells has been put forward when wireless resource amount is satisfied in every small cell. First of all, the method divides the virtual cells. Again through the alternate updating between small cell mapping and wireless resource allocation, least amount of small cells is used and other small cells turn into sleeping state on the premise of guaranteeing users’ QoS. Next, the energy consumption of the wireless access system, wireless resource utilization, and the convergence of the proposed algorithm are analyzed in theory. Finally, the simulation results demonstrate that the algorithm can effectively reduce the system energy consumption and required wireless resource amount under the condition of satisfying users’ QoS.

  1. Towards a QoE-Driven Resource Control in LTE and LTE-A Networks

    Directory of Open Access Journals (Sweden)

    Gerardo Gómez

    2013-01-01

    Full Text Available We propose a novel architecture for providing quality of experience (QoE awareness to mobile operator networks. In particular, we describe a possible architecture for QoE-driven resource control for long-term evolution (LTE and LTE-advanced networks, including a selection of KPIs to be monitored in different network elements. We also provide a description and numerical results of the QoE evaluation process for different data services as well as potential use cases that would benefit from the rollout of the proposed framework.

  2. Social networks and community-based natural resource management.

    Science.gov (United States)

    Lauber, T Bruce; Decker, Daniel J; Knuth, Barbara A

    2008-10-01

    We conducted case studies of three successful examples of collaborative, community-based natural resource conservation and development. Our purpose was to: (1) identify the functions served by interactions within the social networks of involved stakeholders; (2) describe key structural properties of these social networks; and (3) determine how these structural properties varied when the networks were serving different functions. The case studies relied on semi-structured, in-depth interviews of 8 to 11 key stakeholders at each site who had played a significant role in the collaborative projects. Interview questions focused on the roles played by key stakeholders and the functions of interactions between them. Interactions allowed the exchange of ideas, provided access to funding, and enabled some stakeholders to influence others. The exchange of ideas involved the largest number of stakeholders, the highest percentage of local stakeholders, and the highest density of interactions. Our findings demonstrated the value of tailoring strategies for involving stakeholders to meet different needs during a collaborative, community-based natural resource management project. Widespread involvement of local stakeholders may be most appropriate when ideas for a project are being developed. During efforts to exert influence to secure project approvals or funding, however, involving specific individuals with political connections or influence on possible sources of funds may be critical. Our findings are consistent with past work that has postulated that social networks may require specific characteristics to meet different needs in community-based environmental management.

  3. Social Networks and Community-Based Natural Resource Management

    Science.gov (United States)

    Lauber, T. Bruce; Decker, Daniel J.; Knuth, Barbara A.

    2008-10-01

    We conducted case studies of three successful examples of collaborative, community-based natural resource conservation and development. Our purpose was to: (1) identify the functions served by interactions within the social networks of involved stakeholders; (2) describe key structural properties of these social networks; and (3) determine how these structural properties varied when the networks were serving different functions. The case studies relied on semi-structured, in-depth interviews of 8 to 11 key stakeholders at each site who had played a significant role in the collaborative projects. Interview questions focused on the roles played by key stakeholders and the functions of interactions between them. Interactions allowed the exchange of ideas, provided access to funding, and enabled some stakeholders to influence others. The exchange of ideas involved the largest number of stakeholders, the highest percentage of local stakeholders, and the highest density of interactions. Our findings demonstrated the value of tailoring strategies for involving stakeholders to meet different needs during a collaborative, community-based natural resource management project. Widespread involvement of local stakeholders may be most appropriate when ideas for a project are being developed. During efforts to exert influence to secure project approvals or funding, however, involving specific individuals with political connections or influence on possible sources of funds may be critical. Our findings are consistent with past work that has postulated that social networks may require specific characteristics to meet different needs in community-based environmental management.

  4. Adaptive Management of Computing and Network Resources for Spacecraft Systems

    Science.gov (United States)

    Pfarr, Barbara; Welch, Lonnie R.; Detter, Ryan; Tjaden, Brett; Huh, Eui-Nam; Szczur, Martha R. (Technical Monitor)

    2000-01-01

    It is likely that NASA's future spacecraft systems will consist of distributed processes which will handle dynamically varying workloads in response to perceived scientific events, the spacecraft environment, spacecraft anomalies and user commands. Since all situations and possible uses of sensors cannot be anticipated during pre-deployment phases, an approach for dynamically adapting the allocation of distributed computational and communication resources is needed. To address this, we are evolving the DeSiDeRaTa adaptive resource management approach to enable reconfigurable ground and space information systems. The DeSiDeRaTa approach embodies a set of middleware mechanisms for adapting resource allocations, and a framework for reasoning about the real-time performance of distributed application systems. The framework and middleware will be extended to accommodate (1) the dynamic aspects of intra-constellation network topologies, and (2) the complete real-time path from the instrument to the user. We are developing a ground-based testbed that will enable NASA to perform early evaluation of adaptive resource management techniques without the expense of first deploying them in space. The benefits of the proposed effort are numerous, including the ability to use sensors in new ways not anticipated at design time; the production of information technology that ties the sensor web together; the accommodation of greater numbers of missions with fewer resources; and the opportunity to leverage the DeSiDeRaTa project's expertise, infrastructure and models for adaptive resource management for distributed real-time systems.

  5. ANALYSIS RESOURCE AWARE FRAMEWORK BY COMBINING SUNSPOT AND IMOTE2 PLATFORM WIRELESS SENSOR NETWORKS USING DISTANCE VECTOR ALGORITHM

    Directory of Open Access Journals (Sweden)

    Muhammad Ilyas Syarif

    2012-07-01

    Full Text Available Efficiency energy and stream data mining on Wireless Sensor Networks (WSNs are a very interesting issue to be discussed. Routing protocols technology and resource-aware can be done to improve energy efficiency. In this paper we try to merge routing protocol technology using routing Distance Vector and Resource-Aware (RA framework on heterogeneity wireless sensor networks by combining sun-SPOT and Imote2 platform wireless sensor networks. RA perform resource monitoring process of the battery, memory and CPU load more optimally and efficiently. The process uses Light-Weight Clustering (LWC and Light Weight Frequent Item (LWF. The results obtained that by adapting Resource-Aware in wireless sensor networks, the lifetime of wireless sensor improve up to ± 16.62%. Efisiensi energi dan stream data mining pada Wireless Sensor Networks (WSN adalah masalah yang sangat menarik untuk dibahas. Teknologi Routing Protocol dan Resource-Aware dapat dilakukan untuk meningkatkan efisiensi energi. Dalam penelitian ini peneliti mencoba untuk menggabungkan teknologi Routing Protocol menggunakan routing Distance Vector dan Resource-Aware (RA framework pada Wireless Sensor Networks heterogen dengan menggabungkan sun-SPOT dan platform Imote2 Wireless Sensor Networks. RA melakukan proses pemantauan sumber daya dari memori, baterai, dan beban CPU lebih optimal dan efisien. Proses ini menggunakan Light-Weight Clustering (LWC dan Light Weight Frequent Item (LWF. Hasil yang diperoleh bahwa dengan mengadaptasi Resource-Aware dalam Wireless Sensor Networks, masa pakai wireless sensor meningkatkan sampai ± 16,62%.

  6. 78 FR 57845 - Notice of Availability (NOA) for Strategic Network Optimization (SNO) Program Environmental...

    Science.gov (United States)

    2013-09-20

    ... Strategic Network Optimization (SNO) Program Environmental Assessment. SUMMARY: The Defense Logistics Agency... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary Notice of Availability (NOA) for Strategic Network Optimization (SNO) Program...

  7. ANCS: Achieving QoS through Dynamic Allocation of Network Resources in Virtualized Clouds

    Directory of Open Access Journals (Sweden)

    Cheol-Ho Hong

    2016-01-01

    Full Text Available To meet the various requirements of cloud computing users, research on guaranteeing Quality of Service (QoS is gaining widespread attention in the field of cloud computing. However, as cloud computing platforms adopt virtualization as an enabling technology, it becomes challenging to distribute system resources to each user according to the diverse requirements. Although ample research has been conducted in order to meet QoS requirements, the proposed solutions lack simultaneous support for multiple policies, degrade the aggregated throughput of network resources, and incur CPU overhead. In this paper, we propose a new mechanism, called ANCS (Advanced Network Credit Scheduler, to guarantee QoS through dynamic allocation of network resources in virtualization. To meet the various network demands of cloud users, ANCS aims to concurrently provide multiple performance policies; these include weight-based proportional sharing, minimum bandwidth reservation, and maximum bandwidth limitation. In addition, ANCS develops an efficient work-conserving scheduling method for maximizing network resource utilization. Finally, ANCS can achieve low CPU overhead via its lightweight design, which is important for practical deployment.

  8. Diversification of the resources of the Parisian water network : contribution to sustainable management of water resources

    OpenAIRE

    Trinh, Bich-Thuy

    2017-01-01

    At the scale of a city, a sustainable water management raises questions about the links between uses and resources: what water quality is needed for what purpose? The Parisian context is a favourable ground for conducting such type of reflection thanks to the existence of a non-potable water network (RENP) dating from the late nineteenth century. The network is currently supplied by summarily filtrated water from the Seine river (20%) and the canal de l’Ourcql (80%). It is mainly used for mun...

  9. Topological Embedding Feature Based Resource Allocation in Network Virtualization

    Directory of Open Access Journals (Sweden)

    Hongyan Cui

    2014-01-01

    Full Text Available Virtualization provides a powerful way to run multiple virtual networks on a shared substrate network, which needs accurate and efficient mathematical models. Virtual network embedding is a challenge in network virtualization. In this paper, considering the degree of convergence when mapping a virtual network onto substrate network, we propose a new embedding algorithm based on topology mapping convergence-degree. Convergence-degree means the adjacent degree of virtual network’s nodes when they are mapped onto a substrate network. The contributions of our method are as below. Firstly, we map virtual nodes onto the substrate nodes with the maximum convergence-degree. The simulation results show that our proposed algorithm largely enhances the network utilization efficiency and decreases the complexity of the embedding problem. Secondly, we define the load balance rate to reflect the load balance of substrate links. The simulation results show our proposed algorithm achieves better load balance. Finally, based on the feature of star topology, we further improve our embedding algorithm and make it suitable for application in the star topology. The test result shows it gets better performance than previous works.

  10. Resources available for autism research in the big data era: a systematic review

    Directory of Open Access Journals (Sweden)

    Reem Al-jawahiri

    2017-01-01

    Full Text Available Recently, there has been a move encouraged by many stakeholders towards generating big, open data in many areas of research. One area where big, open data is particularly valuable is in research relating to complex heterogeneous disorders such as Autism Spectrum Disorder (ASD. The inconsistencies of findings and the great heterogeneity of ASD necessitate the use of big and open data to tackle important challenges such as understanding and defining the heterogeneity and potential subtypes of ASD. To this end, a number of initiatives have been established that aim to develop big and/or open data resources for autism research. In order to provide a useful data reference for autism researchers, a systematic search for ASD data resources was conducted using the Scopus database, the Google search engine, and the pages on ‘recommended repositories’ by key journals, and the findings were translated into a comprehensive list focused on ASD data. The aim of this review is to systematically search for all available ASD data resources providing the following data types: phenotypic, neuroimaging, human brain connectivity matrices, human brain statistical maps, biospecimens, and ASD participant recruitment. A total of 33 resources were found containing different types of data from varying numbers of participants. Description of the data available from each data resource, and links to each resource is provided. Moreover, key implications are addressed and underrepresented areas of data are identified.

  11. Automated Negotiation for Resource Assignment in Wireless Surveillance Sensor Networks

    Directory of Open Access Journals (Sweden)

    Enrique de la Hoz

    2015-11-01

    Full Text Available Due to the low cost of CMOS IP-based cameras, wireless surveillance sensor networks have emerged as a new application of sensor networks able to monitor public or private areas or even country borders. Since these networks are bandwidth intensive and the radioelectric spectrum is limited, especially in unlicensed bands, it is mandatory to assign frequency channels in a smart manner. In this work, we propose the application of automated negotiation techniques for frequency assignment. Results show that these techniques are very suitable for the problem, being able to obtain the best solutions among the techniques with which we have compared them.

  12. Dynamic optical resource allocation for mobile core networks with software defined elastic optical networking.

    Science.gov (United States)

    Zhao, Yongli; Chen, Zhendong; Zhang, Jie; Wang, Xinbo

    2016-07-25

    Driven by the forthcoming of 5G mobile communications, the all-IP architecture of mobile core networks, i.e. evolved packet core (EPC) proposed by 3GPP, has been greatly challenged by the users' demands for higher data rate and more reliable end-to-end connection, as well as operators' demands for low operational cost. These challenges can be potentially met by software defined optical networking (SDON), which enables dynamic resource allocation according to the users' requirement. In this article, a novel network architecture for mobile core network is proposed based on SDON. A software defined network (SDN) controller is designed to realize the coordinated control over different entities in EPC networks. We analyze the requirement of EPC-lightpath (EPCL) in data plane and propose an optical switch load balancing (OSLB) algorithm for resource allocation in optical layer. The procedure of establishment and adjustment of EPCLs is demonstrated on a SDON-based EPC testbed with extended OpenFlow protocol. We also evaluate the OSLB algorithm through simulation in terms of bandwidth blocking ratio, traffic load distribution, and resource utilization ratio compared with link-based load balancing (LLB) and MinHops algorithms.

  13. Recovery and Resource Allocation Strategies to Maximize Mobile Network Survivability by Using Game Theories and Optimization Techniques

    Directory of Open Access Journals (Sweden)

    Pei-Yu Chen

    2013-01-01

    Full Text Available With more and more mobile device users, an increasingly important and critical issue is how to efficiently evaluate mobile network survivability. In this paper, a novel metric called Average Degree of Disconnectivity (Average DOD is proposed, in which the concept of probability is calculated by the contest success function. The DOD metric is used to evaluate the damage degree of the network, where the larger the value of the Average DOD, the more the damage degree of the network. A multiround network attack-defense scenario as a mathematical model is used to support network operators to predict all the strategies both cyber attacker and network defender would likely take. In addition, the Average DOD would be used to evaluate the damage degree of the network. In each round, the attacker could use the attack resources to launch attacks on the nodes of the target network. Meanwhile, the network defender could reallocate its existing resources to recover compromised nodes and allocate defense resources to protect the survival nodes of the network. In the approach to solving this problem, the “gradient method” and “game theory” are adopted to find the optimal resource allocation strategies for both the cyber attacker and mobile network defender.

  14. Resources available for autism research in the big data era: a systematic review.

    Science.gov (United States)

    Al-Jawahiri, Reem; Milne, Elizabeth

    2017-01-01

    Recently, there has been a move encouraged by many stakeholders towards generating big, open data in many areas of research. One area where big, open data is particularly valuable is in research relating to complex heterogeneous disorders such as Autism Spectrum Disorder (ASD). The inconsistencies of findings and the great heterogeneity of ASD necessitate the use of big and open data to tackle important challenges such as understanding and defining the heterogeneity and potential subtypes of ASD. To this end, a number of initiatives have been established that aim to develop big and/or open data resources for autism research. In order to provide a useful data reference for autism researchers, a systematic search for ASD data resources was conducted using the Scopus database, the Google search engine, and the pages on 'recommended repositories' by key journals, and the findings were translated into a comprehensive list focused on ASD data. The aim of this review is to systematically search for all available ASD data resources providing the following data types: phenotypic, neuroimaging, human brain connectivity matrices, human brain statistical maps, biospecimens, and ASD participant recruitment. A total of 33 resources were found containing different types of data from varying numbers of participants. Description of the data available from each data resource, and links to each resource is provided. Moreover, key implications are addressed and underrepresented areas of data are identified.

  15. Maximizing Interconnectedness and Availability in Directional Airborne RangeExtension Networks

    Science.gov (United States)

    2017-10-25

    surveyed advances in directional networking , noting much work in topology management , medium access control algorithms, aircraft-based directional... networks . Other issues, such as topology management and spectrum management , also require further research and development to enable high-quality...Maximizing Interconnectedness and Availability in Directional Airborne Range Extension Networks Thomas Shake, Rahul Amin MIT Lincoln Laboratory

  16. Assessing the effects of adaptation measures on optimal water resources allocation under varied water availability conditions

    Science.gov (United States)

    Liu, Dedi; Guo, Shenglian; Shao, Quanxi; Liu, Pan; Xiong, Lihua; Wang, Le; Hong, Xingjun; Xu, Yao; Wang, Zhaoli

    2018-01-01

    Human activities and climate change have altered the spatial and temporal distribution of water availability which is a principal prerequisite for allocation of different water resources. In order to quantify the impacts of climate change and human activities on water availability and optimal allocation of water resources, hydrological models and optimal water resource allocation models should be integrated. Given that increasing human water demand and varying water availability conditions necessitate adaptation measures, we propose a framework to assess the effects of these measures on optimal allocation of water resources. The proposed model and framework were applied to a case study of the middle and lower reaches of the Hanjiang River Basin in China. Two representative concentration pathway (RCP) scenarios (RCP2.6 and RCP4.5) were employed to project future climate, and the Variable Infiltration Capacity (VIC) hydrological model was used to simulate the variability of flows under historical (1956-2011) and future (2012-2099) conditions. The water availability determined by simulating flow with the VIC hydrological model was used to establish the optimal water resources allocation model. The allocation results were derived under an extremely dry year (with an annual average water flow frequency of 95%), a very dry year (with an annual average water flow frequency of 90%), a dry year (with an annual average water flow frequency of 75%), and a normal year (with an annual average water flow frequency of 50%) during historical and future periods. The results show that the total available water resources in the study area and the inflow of the Danjiangkou Reservoir will increase in the future. However, the uneven distribution of water availability will cause water shortage problems, especially in the boundary areas. The effects of adaptation measures, including water saving, and dynamic control of flood limiting water levels (FLWLs) for reservoir operation, were

  17. Resource Allocation for Multicell Device-to-Device Communications in Cellular Network: A Game Theoretic Approach

    Directory of Open Access Journals (Sweden)

    Jun Huang

    2015-08-01

    Full Text Available Device-to-Device (D2D communication has recently emerged as a promising technology to improve the capacity and coverage of cellular systems. To successfully implement D2D communications underlaying a cellular network, resource allocation for D2D links plays a critical role. While most of prior resource allocation mechanisms for D2D communications have focused on interference within a single-cell system, this paper investigates the resource allocation problem for a multicell cellular network in which a D2D link reuses available spectrum resources of multiple cells. A repeated game theoretic approach is proposed to address the problem. In this game, the base stations (BSs act as players that compete for resource supply of D2D, and the utility of each player is formulated as revenue collected from both cellular and D2D users using resources. Extensive simulations are conducted to verify the proposed approach and the results show that it can considerably enhance the system performance in terms of sum rate and sum rate gain.

  18. Extent of the availability of Africana resources in subject areas in ...

    African Journals Online (AJOL)

    The study investigated the extent of the availability of Africana resources in various subject areas in thirteen first and second generation federal university libraries in Nigeria with the view of suggesting ways to improve the development of the collection in the university libraries that are deficient in the subject areas of any of ...

  19. Availability of recreational resources in minority and low socioeconomic status areas.

    Science.gov (United States)

    Moore, Latetia V; Diez Roux, Ana V; Evenson, Kelly R; McGinn, Aileen P; Brines, Shannon J

    2008-01-01

    Differences in availability of recreational resources may contribute to racial and socioeconomic status (SES) disparities in physical activity. Variations in the location and density of recreational resources were examined by SES and racial composition of neighborhoods. Densities of resources available in recreational facilities and parks were estimated for census tracts between April 2003 and June 2004 in North Carolina, New York, and Maryland using kernel estimation. The probability of not having a facility or park was modeled by tract racial composition and SES, adjusting for population and area, using binomial regression in 2006. Mean densities of tract resources were modeled by SES and racial composition using linear regression. Minority neighborhoods were significantly more likely than white neighborhoods not to have recreational facilities (relative probability [RP]=3.27 [95% CI=2.11-5.07] and 8.60 [95% CI=4.48-16.51], for black and Hispanic neighborhoods, respectively). Low-income neighborhoods were 4.5 times more likely to not have facilities than high-income areas (95% CI=2.87-7.12). Parks were more equitably distributed. Most resources located in recreational facilities required a fee and were less dense in minority and low-income areas. Those located inside parks were usually free to use, sports-related, and denser in poor and minority neighborhoods. Recreational facilities and the resources they offer are not equitably distributed. The presence of parks in poor and minority areas suggest that improving the types and quality of resources in parks could be an important strategy to increase physical activity and reduce racial/ethnic and socioeconomic disparities.

  20. Resource allocation for phantom cellular networks: Energy efficiency vs spectral efficiency

    KAUST Repository

    Abdelhady, Amr M.

    2016-07-26

    Multi-tier heterogeneous networks have become an essential constituent for next generation cellular networks. Mean-while, energy efficiency (EE) has been considered a critical design criterion along with the traditional spectral efficiency (SE) metric. In this context, we study power and spectrum allocation for the recently proposed two-tier network architecture known as phantom cellular networks. The optimization framework includes both EE and SE, where we propose an algorithm that finds the SE and EE resource allocation strategies for phantom cellular networks. Then, we compare the performance of both design strategies versus the number of users, and phantom cells share of the total number of available resource blocks. We aim to investigate the effect of some system parameters to achieve improved SE performance at a non-significant loss in EE performance, or vice versa. It was found that increasing phantom cells share of resource blocks decreases the SE performance loss due to EE optimization when compared with the optimized SE performance. © 2016 IEEE.

  1. Resource stoichiometry and availability modulate species richness and biomass of tropical litter macro-invertebrates.

    Science.gov (United States)

    Jochum, Malte; Barnes, Andrew D; Weigelt, Patrick; Ott, David; Rembold, Katja; Farajallah, Achmad; Brose, Ulrich

    2017-09-01

    of litter mass for both species richness and biomass indicates that these tropical consumers strongly depend on habitat space and resource availability. Our study supports previous theoretical work indicating that consumer species richness is jointly influenced by resource availability and the balanced supply of multiple chemical elements in their resources. © 2017 The Authors. Journal of Animal Ecology © 2017 British Ecological Society.

  2. Advanced Distribution Network Modelling with Distributed Energy Resources

    Science.gov (United States)

    O'Connell, Alison

    The addition of new distributed energy resources, such as electric vehicles, photovoltaics, and storage, to low voltage distribution networks means that these networks will undergo major changes in the future. Traditionally, distribution systems would have been a passive part of the wider power system, delivering electricity to the customer and not needing much control or management. However, the introduction of these new technologies may cause unforeseen issues for distribution networks, due to the fact that they were not considered when the networks were originally designed. This thesis examines different types of technologies that may begin to emerge on distribution systems, as well as the resulting challenges that they may impose. Three-phase models of distribution networks are developed and subsequently utilised as test cases. Various management strategies are devised for the purposes of controlling distributed resources from a distribution network perspective. The aim of the management strategies is to mitigate those issues that distributed resources may cause, while also keeping customers' preferences in mind. A rolling optimisation formulation is proposed as an operational tool which can manage distributed resources, while also accounting for the uncertainties that these resources may present. Network sensitivities for a particular feeder are extracted from a three-phase load flow methodology and incorporated into an optimisation. Electric vehicles are the focus of the work, although the method could be applied to other types of resources. The aim is to minimise the cost of electric vehicle charging over a 24-hour time horizon by controlling the charge rates and timings of the vehicles. The results demonstrate the advantage that controlled EV charging can have over an uncontrolled case, as well as the benefits provided by the rolling formulation and updated inputs in terms of cost and energy delivered to customers. Building upon the rolling optimisation, a

  3. Resources for physical activity participation: does availability and accessibility differ by neighborhood socioeconomic status?

    Science.gov (United States)

    Estabrooks, Paul A; Lee, Rebecca E; Gyurcsik, Nancy C

    2003-01-01

    The purpose of this study was to determine whether the availability and accessibility of physical activity resources differed by neighborhood socioeconomic status (SES) in a small U.S. city (population = 133,046). U.S. census tracts (N =32) were used to represent neighborhoods and categorized into high, medium, or low SES on the basis of the percentage of unemployed individuals, per capita income, and percentage of the population below the poverty threshold. We developed a geographic information system to generate a comprehensive list of physical activity resources available within each census tract in the city. We identified 112 parks, 33 sport facilities, 15 fitness clubs, 11 community centers, and 5 walking/biking trails. The total number of physical activity resources varied by neighborhood SES (p <.05); low-SES (M =4.5-/+2.3) and medium-SES (M =4.9-/+2.6) neighborhoods had significantly fewer resources than high-SES (M =8.4-/+3.5) neighborhoods. Low-, medium-, and high-SES neighborhoods did not differ on the number of pay-for-use facilities; however, low-SES (M =3.1-/+1.5) and medium-SES (M =3.8-/+1.6) neighborhoods had significantly fewer free-for-use resources than high- (M =6.1-/+2.4) SES neighborhoods (p <.01). Data suggest that individuals from lower SES neighborhoods may have limited ability to control their physical activity in the face of inaccessible environments. Community research and promotion efforts should include assessment and targeting of available and accessible physical activity resources.

  4. Blockchain-Empowered Fair Computational Resource Sharing System in the D2D Network

    Directory of Open Access Journals (Sweden)

    Zhen Hong

    2017-11-01

    Full Text Available Device-to-device (D2D communication is becoming an increasingly important technology in future networks with the climbing demand for local services. For instance, resource sharing in the D2D network features ubiquitous availability, flexibility, low latency and low cost. However, these features also bring along challenges when building a satisfactory resource sharing system in the D2D network. Specifically, user mobility is one of the top concerns for designing a cooperative D2D computational resource sharing system since mutual communication may not be stably available due to user mobility. A previous endeavour has demonstrated and proven how connectivity can be incorporated into cooperative task scheduling among users in the D2D network to effectively lower average task execution time. There are doubts about whether this type of task scheduling scheme, though effective, presents fairness among users. In other words, it can be unfair for users who contribute many computational resources while receiving little when in need. In this paper, we propose a novel blockchain-based credit system that can be incorporated into the connectivity-aware task scheduling scheme to enforce fairness among users in the D2D network. Users’ computational task cooperation will be recorded on the public blockchain ledger in the system as transactions, and each user’s credit balance can be easily accessible from the ledger. A supernode at the base station is responsible for scheduling cooperative computational tasks based on user mobility and user credit balance. We investigated the performance of the credit system, and simulation results showed that with a minor sacrifice of average task execution time, the level of fairness can obtain a major enhancement.

  5. Supporting Veterans in Massachusetts: An Assessment of Needs, Well-Being, and Available Resources.

    Science.gov (United States)

    Farmer, Carrie M; Tanielian, Terri; Fischer, Shira H; Duffy, Erin L; Dellva, Stephanie; Butcher, Emily; Brown, Kristine M; Hoch, Emily

    2017-01-01

    Massachusetts is home to approximately 380,000 of the nation's more than 21 million veterans, but there has been little research on the resources available to this population at the state level. There are numerous resources available to veterans and other military-affiliated groups in Massachusetts, but there are still pockets of unmet need in the areas of education, employment, health care, housing, financial, and legal services-particularly for newer veterans and current National Guard/reserve members. Although Massachusetts veterans fare better overall than their peers in other states, they lag behind other Massachusetts residents in terms of health and financial status. Massachusetts veterans and National Guard/reserve members who need support and services face such barriers as a lack of knowledge about how to access services, a lack of awareness about eligibility, and geographic distance from service providers. As the veteran population changes both nationally and in Massachusetts, it will be important for public- and private-sector providers serving Massachusetts veterans and service members to continue addressing unmet needs while ensuring that resources are responsive to shifts in these populations. A better understanding of the unique needs of Massachusetts veterans can help inform investments in initiatives that target these populations and guide efforts to remedy barriers to accessing available support services and other resources.

  6. The Influence of Ethnic Diversity on Social Network Structure in a Common-Pool Resource System: Implications for Collaborative Management

    Directory of Open Access Journals (Sweden)

    Michele Barnes-Mauthe

    2013-03-01

    Full Text Available Social networks have recently been identified as key features in facilitating or constraining collaborative arrangements that can enhance resource governance and adaptability in complex social-ecological systems. Nonetheless, the effect of ethnicity on social network structure in an ethnically diverse common-pool resource system is virtually unknown. We characterize the entire social network of Hawaii's longline fishery, an ethnically diverse competitive pelagic fishery, and investigate network homophily, network structure, and cross-scale linkages. Results show that ethnicity significantly influences social network structure and is responsible for a homophily effect, which can create challenges for stakeholder collaboration across groups. Our analysis also suggests that ethnicity influences the formation of diverse network structures, and can affect the level of linkages to outside industry leaders, government or management officials, and members of the scientific community. This study provides the first empirical examination of the impact of ethnic diversity on resource user's social networks in the common-pool resource literature, having important implications for collaborative resource management.

  7. Combined Resource Allocation System for Device-to-Device Communication towards LTE Networks

    Directory of Open Access Journals (Sweden)

    Abbas Fakhar

    2016-01-01

    Full Text Available The LTE networks are being developed to grant mobile broadband services in the fourth generation (4G systems and allow operators to use spectrum more efficiently.D2D communication is a promising technique to provide wireless services and enhance spectrum exploitation in the LTE Heterogeneous Networks (HetNets.D2D communication in HetNets allows users to communicate with each other directly by reusing the resources when communicating via the base stations. But during the downlink period, both the D2D receiver and the Heterogeneous Users equipment’s (HUE experience interference caused by resource allocation. In this article, we identify and analyze the interference problem of HetNets caused by D2D transmitter during download. We propose a combined resource allocation and resource reuse method for LTE HetNets, where resource allocation to HUEs is employed on the basis of comparative fair algorithm and resource reuse to D2D users is employed on acquisitive empirical algorithm. This approach evaluates whether D2D mode is suitable or not by path loss evaluation, after that decreases the interference to HUE by selection of the minimum channel gain between HUE and D2D transmitter each time to mitigate interference. Our simulation results show that the efficiency and throughput of HetNets is improved by using the proposed method.

  8. Software for Allocating Resources in the Deep Space Network

    Science.gov (United States)

    Wang, Yeou-Fang; Borden, Chester; Zendejas, Silvino; Baldwin, John

    2003-01-01

    TIGRAS 2.0 is a computer program designed to satisfy a need for improved means for analyzing the tracking demands of interplanetary space-flight missions upon the set of ground antenna resources of the Deep Space Network (DSN) and for allocating those resources. Written in Microsoft Visual C++, TIGRAS 2.0 provides a single rich graphical analysis environment for use by diverse DSN personnel, by connecting to various data sources (relational databases or files) based on the stages of the analyses being performed. Notable among the algorithms implemented by TIGRAS 2.0 are a DSN antenna-load-forecasting algorithm and a conflict-aware DSN schedule-generating algorithm. Computers running TIGRAS 2.0 can also be connected using SOAP/XML to a Web services server that provides analysis services via the World Wide Web. TIGRAS 2.0 supports multiple windows and multiple panes in each window for users to view and use information, all in the same environment, to eliminate repeated switching among various application programs and Web pages. TIGRAS 2.0 enables the use of multiple windows for various requirements, trajectory-based time intervals during which spacecraft are viewable, ground resources, forecasts, and schedules. Each window includes a time navigation pane, a selection pane, a graphical display pane, a list pane, and a statistics pane.

  9. Scheduling preemptable jobs on identical processors under varying availability of an additional continuous resource

    Directory of Open Access Journals (Sweden)

    Różycki Rafał

    2016-09-01

    Full Text Available In this work we consider a problem of scheduling preemptable, independent jobs, characterized by the fact that their processing speeds depend on the amounts of a continuous, renewable resource allocated to jobs at a time. Jobs are scheduled on parallel, identical machines, with the criterion of minimization of the schedule length. Since two categories of resources occur in the problem: discrete (set of machines and continuous, it is generally called a discrete-continuous scheduling problem. The model studied in this paper allows the total available amount of the continuous resource to vary over time, which is a practically important generalization that has not been considered yet for discrete-continuous scheduling problems. For this model we give some properties of optimal schedules on a basis of which we propose a general methodology for solving the considered class of problems. The methodology uses a two-phase approach in which, firstly, an assignment of machines to jobs is defined and, secondly, for this assignment an optimal continuous resource allocation is found by solving an appropriate mathematical programming problem. In the approach various cases are considered, following from assumptions made on the form of the processing speed functions of jobs. For each case an iterative algorithm is designed, leading to an optimal solution in a finite number of steps.

  10. Information on Resources Available on the Land Lot for Integrated Building Design

    Directory of Open Access Journals (Sweden)

    Vytautas Martinaitis

    2013-10-01

    Full Text Available The most progress in the area of the sustainable building policy and its implementation has been achieved in certain regions by the Building Certification System regulations such as Passivhaus (Germany and LEED (U.S. These solutions are similar to the more widely discussed and already applied concepts: the Integrated Whole Building Design (IWBD and Building Information Modeling (BIM. Although it may sound trivial, it is vital to acknowledge and understand that a building is an integral component of the land lot. In the stage of development of a building concept, it usually lacks a versatile and professional assessment of available resources, especially those of renewable energy. It is suggested at the beginning of the IWBD concept to conduct such assessment on the resources available and more specifically focusing on renewable energy. The assessment should also meet the expectations of the building’s owner to use effectively the potential of all possible solutions. Thus a certificate is drawn up, defining all the resources available for the particular lot. The structure of the certificate data is orientated towards the possibility of designing modern renewable energy technologies, according to their performance under changing weather conditions during the year. Such assessment certificates contribute to shaping the concept of the building and allow achieving the highest level of its sustainability.Article in Lithuanian

  11. Home range size variation in female arctic grizzly bears relative to reproductive status and resource availability.

    Directory of Open Access Journals (Sweden)

    Mark A Edwards

    Full Text Available The area traversed in pursuit of resources defines the size of an animal's home range. For females, the home range is presumed to be a function of forage availability. However, the presence of offspring may also influence home range size due to reduced mobility, increased nutritional need, and behavioral adaptations of mothers to increase offspring survival. Here, we examine the relationship between resource use and variation in home range size for female barren-ground grizzly bears (Ursus arctos of the Mackenzie Delta region in Arctic Canada. We develop methods to test hypotheses of home range size that address selection of cover where cover heterogeneity is low, using generalized linear mixed-effects models and an information-theoretic approach. We found that the reproductive status of female grizzlies affected home range size but individually-based spatial availability of highly selected cover in spring and early summer was a stronger correlate. If these preferred covers in spring and early summer, a period of low resource availability for grizzly bears following den-emergence, were patchy and highly dispersed, females travelled farther regardless of the presence or absence of offspring. Increased movement to preferred covers, however, may result in greater risk to the individual or family.

  12. Resource Availability Alters Biodiversity Effects in Experimental Grass-Forb Mixtures.

    Directory of Open Access Journals (Sweden)

    Alrun Siebenkäs

    Full Text Available Numerous experiments, mostly performed in particular environments, have shown positive diversity-productivity relationships. Although the complementary use of resources is discussed as an important mechanism explaining diversity effects, less is known about how resource availability controls the strength of diversity effects and how this response depends on the functional composition of plant communities. We studied aboveground biomass production in experimental monocultures, two- and four-species mixtures assembled from two independent pools of four perennial grassland species, each representing two functional groups (grasses, forbs and two growth statures (small, tall, and exposed to different combinations of light and nutrient availability. On average, shade led to a decrease in aboveground biomass production of 24% while fertilization increased biomass production by 36%. Mixtures were on average more productive than expected from their monocultures (relative yield total, RYT>1 and showed positive net diversity effects (NE: +34% biomass increase; mixture minus mean monoculture biomass. Both trait-independent complementarity effects (TICE: +21% and dominance effects (DE: +12% positively contributed to net diversity effects, while trait-dependent complementarity effects were minor (TDCE: +1%. Shading did not alter diversity effects and overyielding. Fertilization decreased RYT and the proportion of biomass gain through TICE and TDCE, while DE increased. Diversity effects did not increase with species richness and were independent of functional group or growth stature composition. Trait-based analyses showed that the dominance of species with root and leaf traits related to resource conservation increased TICE. Traits indicating the tolerance of shade showed positive relationships with TDCE. Large DE were associated with the dominance of species with tall growth and low diversity in leaf nitrogen concentrations. Our field experiment shows that

  13. Traffic Steering Framework for Mobile-Assisted Resource Management in Heterogeneous Networks

    DEFF Research Database (Denmark)

    Dogadaev, Anton Konstantinovich; Checko, Aleksandra; Popovska Avramova, Andrijana

    2013-01-01

    With the expected growth of mobile data traffic it is essential to manage the network resources efficiently. In order to undertake this challenge, we propose a framework for network-centric, mobile-assisted resource management, which facilitates traffic offloading from mobile network to Wi...

  14. Flooding disturbances increase resource availability and productivity but reduce stability in diverse plant communities.

    Science.gov (United States)

    Wright, Alexandra J; Ebeling, Anne; de Kroon, Hans; Roscher, Christiane; Weigelt, Alexandra; Buchmann, Nina; Buchmann, Tina; Fischer, Christine; Hacker, Nina; Hildebrandt, Anke; Leimer, Sophia; Mommer, Liesje; Oelmann, Yvonne; Scheu, Stefan; Steinauer, Katja; Strecker, Tanja; Weisser, Wolfgang; Wilcke, Wolfgang; Eisenhauer, Nico

    2015-01-20

    The natural world is increasingly defined by change. Within the next 100 years, rising atmospheric CO₂ concentrations will continue to increase the frequency and magnitude of extreme weather events. Simultaneously, human activities are reducing global biodiversity, with current extinction rates at ~1,000 × what they were before human domination of Earth's ecosystems. The co-occurrence of these trends may be of particular concern, as greater biological diversity could help ecosystems resist change during large perturbations. We use data from a 200-year flood event to show that when a disturbance is associated with an increase in resource availability, the opposite may occur. Flooding was associated with increases in productivity and decreases in stability, particularly in the highest diversity communities. Our results undermine the utility of the biodiversity-stability hypothesis during a large number of disturbances where resource availability increases. We propose a conceptual framework that can be widely applied during natural disturbances.

  15. Non-renewable Resources in Asian Economies: Perspective of Availability, Applicability Acceptability, and Affordability

    OpenAIRE

    Youngho CHANG; Yanfei LI

    2014-01-01

    This paper reviews the factors that determine the sustainability of nonrenewable energy production and consumption in Asian economies. It reviews the recent literature on the issue and all of the key findings under the 4As framework (Availability, Applicability, Acceptability, and Affordability) which is derived from the classical Hotelling non-renewable resource economics models. Conclusions derived focus on the implications of the fast growth in non-renewable energy consumption and its outp...

  16. 76 FR 64100 - Notice of Availability of Record of Decision for the Little Snake Resource Management Plan...

    Science.gov (United States)

    2011-10-17

    ... Bureau of Land Management Notice of Availability of Record of Decision for the Little Snake Resource... (ROD)/Approved Resource Management Plan (RMP) for the Little Snake Field Office located in northwest.... The management actions in the ROD/RMP seek a balance of resource protection and resource use. Some of...

  17. Home range size variation in female arctic grizzly bears relative to reproductive status and resource availability.

    Science.gov (United States)

    Edwards, Mark A; Derocher, Andrew E; Nagy, John A

    2013-01-01

    The area traversed in pursuit of resources defines the size of an animal's home range. For females, the home range is presumed to be a function of forage availability. However, the presence of offspring may also influence home range size due to reduced mobility, increased nutritional need, and behavioral adaptations of mothers to increase offspring survival. Here, we examine the relationship between resource use and variation in home range size for female barren-ground grizzly bears (Ursus arctos) of the Mackenzie Delta region in Arctic Canada. We develop methods to test hypotheses of home range size that address selection of cover where cover heterogeneity is low, using generalized linear mixed-effects models and an information-theoretic approach. We found that the reproductive status of female grizzlies affected home range size but individually-based spatial availability of highly selected cover in spring and early summer was a stronger correlate. If these preferred covers in spring and early summer, a period of low resource availability for grizzly bears following den-emergence, were patchy and highly dispersed, females travelled farther regardless of the presence or absence of offspring. Increased movement to preferred covers, however, may result in greater risk to the individual or family.

  18. Influences of Climate Change on Water Resources Availability in Jinjiang Basin, China

    Directory of Open Access Journals (Sweden)

    Wenchao Sun

    2014-01-01

    Full Text Available The influences of climate change on water resources availability in Jinjiang Basin, China, were assessed using the Block-wise use of the TOPmodel with the Muskingum-Cunge routing method (BTOPMC distributed hydrological model. The ensemble average of downscaled output from sixteen GCMs (General Circulation Models for A1B emission scenario (medium CO2 emission in the 2050s was adopted to build regional climate change scenario. The projected precipitation and temperature data were used to drive BTOPMC for predicting hydrological changes in the 2050s. Results show that evapotranspiration will increase in most time of a year. Runoff in summer to early autumn exhibits an increasing trend, while in the rest period of a year it shows a decreasing trend, especially in spring season. From the viewpoint of water resource availability, it is indicated that it has the possibility that water resources may not be sufficient to fulfill irrigation water demand in the spring season and one possible solution is to store more water in the reservoir in previous summer.

  19. Resource Allocation in a Generalized Framework for Virtualized Heterogeneous Wireless Network

    Directory of Open Access Journals (Sweden)

    Bo Fan

    2016-01-01

    Full Text Available As a prevailing concept in 5G, virtualization provides efficient coordination among multiple radio access technologies (RATs and enables multiple service providers (SPs to share different RATs’ infrastructure. This paper proposes a generic framework for virtualizing heterogeneous wireless network with different RATs. A novel “VMAC” (virtualized medium access control concept is introduced to converge different RAT protocols and perform inter-RAT resource allocation. To suit the proposed framework, a virtualization based resource allocation scheme is devised. We formulate the problem as a mixed combinatorial optimization, which jointly considers network access and rate allocation. First, to solve the network access problem, “adaptability ratio” is developed to model the fact that different RATs possess different adaptability to different services. And a Grey Relational Analysis (GRA method is adopted to calculate the adaptability ratio. Second, services are modeled as players, bargaining for RAT resources in a Nash bargaining game. And a closed-form Nash bargaining solution (NBS is derived. Combining adaptability ratio with NBS, a novel resource allocation algorithm is devised. Through simulation, the superiority and feasibility of the proposed algorithm are validated.

  20. Mental imagery interventions reduce subsequent food intake only when self-regulatory resources are available

    Directory of Open Access Journals (Sweden)

    Benjamin eMissbach

    2014-11-01

    Full Text Available Research has shown that imagining food consumption leads to food-specific habituation effects. In the present research, we replicated these effects and further examined whether the depletion of self-regulatory resources would reduce the habituation effects of imagined food consumption. Since self-regulatory resources have been shown to reduce habituation effects during the perception of emotional stimuli, we expected a reduction in habituation effects from imagined food consumption when self-regulatory resources were depleted. In Study 1, we replicated habituation effects as a response to imagining gummy bear consumption with a high (36 and medium number (18 of repetitions in a camouflaged taste test. Participants imagining gummy bear intake showed decreased food intake compared with participants who imagined putting a coin into a laundry machine. The number of repetitions did not significantly moderate the observed habituation effect. In Study 2, we investigated whether self-regulatory depletion would impede habituation effects evoked by the imagination of walnut consumption. Participants in a depleted state did not show a reduction in food intake after imagining walnut intake compared with participants in a non-depleted state. We discuss directions for future research and processes that might underlie the observed moderating effect of self-regulatory resources.

  1. Resource-Aware Data Fusion Algorithms for Wireless Sensor Networks

    CERN Document Server

    Abdelgawad, Ahmed

    2012-01-01

    This book introduces resource-aware data fusion algorithms to gather and combine data from multiple sources (e.g., sensors) in order to achieve inferences.  These techniques can be used in centralized and distributed systems to overcome sensor failure, technological limitation, and spatial and temporal coverage problems. The algorithms described in this book are evaluated with simulation and experimental results to show they will maintain data integrity and make data useful and informative.   Describes techniques to overcome real problems posed by wireless sensor networks deployed in circumstances that might interfere with measurements provided, such as strong variations of pressure, temperature, radiation, and electromagnetic noise; Uses simulation and experimental results to evaluate algorithms presented and includes real test-bed; Includes case study implementing data fusion algorithms on a remote monitoring framework for sand production in oil pipelines.

  2. Resources

    Science.gov (United States)

    ... disease - resources Hemophilia - resources Herpes - resources Incest - resources Incontinence - resources Infertility - resources Interstitial cystitis - resources Kidney disease - resources Leukemia - resources Liver disease - resources Loss ...

  3. Influence of spatio-temporal resource availability on mushroom mite diversity.

    Science.gov (United States)

    Okabe, Kimiko

    2013-11-01

    Although biodiversity in nature is of fundamental importance because it improves the sustainability of ecosystems, communities of microscopic organisms are generally excluded from conservation targets for biodiversity. Here, I hypothesize that mushroom mite species richness is correlated with both spatial (i.e., mushroom size) and temporal (i.e., longevity of fruiting bodies) resource availability. I collected fruiting bodies in an old-growth forest over 4 years to collect mites and insects inhabiting the mushrooms. Mites were collected from 47 % of the fruiting bodies and approximately 60 % of the mite species were collected only once. Mite species richness was significantly correlated with the availability of long-lasting fruiting bodies. For example, bracket fungi contained more mite species than ephemeral fruiting bodies. Insect presence was also correlated with mushroom mite richness, probably as phoretic hosts and food resources for predacious mites. On the other hand, mushroom size seemed to be less important; small fruiting bodies sometimes harbored several mite species. Although mite species richness was correlated with mushroom species richness, mushroom specificity by mites was not clear except for a preference for long-lasting fruiting bodies. Therefore, I suggest that a constant supply of coarse woody debris is crucial for maintaining preferred resources for mushroom mites (e.g., bracket fungi) and their associated insects (mycophilous and possibly saproxylic insects).

  4. The Impact of Water Regulation on the Availability of Shale Gas Resources for Production

    Science.gov (United States)

    Victor, D. G.

    2011-12-01

    Visions for a large increase in North American production of natural gas from shale are based heavily on the sharp rise in the estimated available resource. Those estimates are prepared by looking at the underlying geology as well as the cost and availability of technologies for extracting gas. We add to that equation the potential current and future regulation of water injection (subsurface) and runoff (surface). Using the political science theory of "veto points" we show that US water legislation is organized in ways that allow for large numbers of political forces to block (or make costly) access to gas resources. By our estimate, 26% of the shale gas resource will be unavailable-a fraction that could rise if there are strong contagion effects as jurisdictions that have traditionally had industry-friendly regulatory systems apply much stricter rules. This work has potentially large implications for visions of the new natural gas revolution and the price of North American (and potentially world) natural gas.

  5. Influences of climate change on water resources availability in Jinjiang Basin, China.

    Science.gov (United States)

    Sun, Wenchao; Wang, Jie; Li, Zhanjie; Yao, Xiaolei; Yu, Jingshan

    2014-01-01

    The influences of climate change on water resources availability in Jinjiang Basin, China, were assessed using the Block-wise use of the TOPmodel with the Muskingum-Cunge routing method (BTOPMC) distributed hydrological model. The ensemble average of downscaled output from sixteen GCMs (General Circulation Models) for A1B emission scenario (medium CO2 emission) in the 2050s was adopted to build regional climate change scenario. The projected precipitation and temperature data were used to drive BTOPMC for predicting hydrological changes in the 2050s. Results show that evapotranspiration will increase in most time of a year. Runoff in summer to early autumn exhibits an increasing trend, while in the rest period of a year it shows a decreasing trend, especially in spring season. From the viewpoint of water resource availability, it is indicated that it has the possibility that water resources may not be sufficient to fulfill irrigation water demand in the spring season and one possible solution is to store more water in the reservoir in previous summer.

  6. Evaluation of intersectoral resources in the composition of care networks for crack users

    Directory of Open Access Journals (Sweden)

    Leandro Barbosa de Pinho

    2017-10-01

    Full Text Available Abstract Objective: To evaluate the intersectoral resources in the composition of care networks for crack users. Method: Evaluative, qualitative study based on the Fourth Generation Evaluation. The participants were 10 users, 11 family members, eight workers, and seven managers from a municipality in the metropolitan region of Porto Alegre/Rio Grande do Sul, Brazil. Data were collected in 2014 through observation and semi-structured interviews. The analysis occurred by the constant comparative method. Results: Stakeholders have discussed how the Public Prosecutor's Office and the Military Brigade are inserted in the network, since they carry out actions that often are not compatible with the psychosocial care proposal. The need for expansion and maintenance of liaisons with community resources was identified. Conclusion: It is noted the need for sector integration and participation of all social agents from different spheres in order to promote and evaluate the practices and policies of care for crack users.

  7. Performance Analysis of Economic Model and Radio Resource Management in Heterogeneous Wireless Networks

    OpenAIRE

    Nilkantha Chakraborty

    2013-01-01

    Radio resource management (RRM) is the system level control of co-channel interference and other radio transmission characteristics in wireless communication systems. In this paper we first analyze a utility function based access selection (UFAS) method. Thenwe investigate a radio resource management and network selection scheme in heterogeneous wireless network. We propose an economic model to allocate radio resources for Code Division Multiple Access (CDMA) Networks and Wireless local Area ...

  8. Link and route availability for Inter-working multi-hop wireless networks

    CSIR Research Space (South Africa)

    Salami, O

    2009-09-01

    Full Text Available In inter-working multi-hop wireless networks, establishing resilient connectivity between source-destination node pairs is a major issue. The issue of connectivity in multi-hop wireless networks have been studied. However, these analyses focused...

  9. Increasing the cost-constrained availability of WDM Networks with Degree-3 Structured Topologies

    DEFF Research Database (Denmark)

    Gutierrez Lopez, Jose Manuel; Georgakilas, Kostas; Katrinis, Kostas

    2010-01-01

    This paper studies the impact of node degree distribution to availability and capital and deployment expenditure of optical WDM transport networks. Three structured degree-3 graphs with fair node degree distribution are proposed in this context. Using a realistic network optimization framework...

  10. Efficient Resource Scheduling by Exploiting Relay Cache for Cellular Networks

    Directory of Open Access Journals (Sweden)

    Chun He

    2015-01-01

    Full Text Available In relay-enhanced cellular systems, throughput of User Equipment (UE is constrained by the bottleneck of the two-hop link, backhaul link (or the first hop link, and access link (the second hop link. To maximize the throughput, resource allocation should be coordinated between these two hops. A common resource scheduling algorithm, Adaptive Distributed Proportional Fair, only ensures that the throughput of the first hop is greater than or equal to that of the second hop. But it cannot guarantee a good balance of the throughput and fairness between the two hops. In this paper, we propose a Two-Hop Balanced Distributed Scheduling (TBS algorithm by exploiting relay cache for non-real-time data traffic. The evolved Node Basestation (eNB adaptively adjusts the number of Resource Blocks (RBs allocated to the backhaul link and direct links based on the cache information of relays. Each relay allocates RBs for relay UEs based on the size of the relay UE’s Transport Block. We also design a relay UE’s ACK feedback mechanism to update the data at relay cache. Simulation results show that the proposed TBS can effectively improve resource utilization and achieve a good trade-off between system throughput and fairness by balancing the throughput of backhaul and access link.

  11. Unmet Supportive Care Needs in U.S. Dialysis Centers and Lack of Knowledge of Available Resources to Address Them.

    Science.gov (United States)

    Culp, Stacey; Lupu, Dale; Arenella, Cheryl; Armistead, Nancy; Moss, Alvin H

    2016-04-01

    Because of high symptom burden, numerous comorbidities, and shortened life expectancy, dialysis patients are increasingly recognized as appropriate candidates for early and continuous supportive care. The objectives of this study were to describe dialysis professionals' perceptions of the adequacy of supportive care in dialysis centers, barriers to providing it, suggestions for improving it, and familiarity with the existing evidence-based resources for supportive care of dialysis patients. The Coalition for Supportive Care of Kidney Patients conducted an online survey of dialysis professionals and administrators solicited through the 18 End-Stage Renal Disease Networks and the Renal Physicians Association. Only 4.5% of 487 respondents believed their dialysis centers were presently providing high-quality supportive care. They identified bereavement support, spiritual support, and end-of-life care discussions as the top three unmet needs. They reported that lack of a predictive algorithm for prognosis was the top barrier, and "guidelines to help with decision-making in seriously ill patients" was the top priority to improve supportive care. A majority of respondents were unaware that an evidence-based validated prognostic model and a clinical practice guideline to help with decision-making were already available. Dialysis professionals report significant unmet supportive care needs and barriers in their centers with only a small minority rating themselves as competently providing supportive care. There is an urgent need for education of dialysis professionals about available supportive care resources to provide quality supportive care to dialysis patients. Copyright © 2016. Published by Elsevier Inc.

  12. Shorter Fallow Cycles Affect the Availability of Noncrop Plant Resources in a Shifting Cultivation System

    Directory of Open Access Journals (Sweden)

    Sarah Paule. Dalle

    2006-12-01

    Full Text Available Shifting cultivation systems, one of the most widely distributed forms of agriculture in the tropics, provide not only crops of cultural significance, but also medicinal, edible, ritual, fuel, and forage resources, which contribute to the livelihoods, health, and cultural identity of local people. In many regions across the globe, shifting cultivation systems are undergoing important changes, one of the most pervasive being a shortening of the fallow cycle. Although there has been much attention drawn to declines in crop yields in conjunction with reductions in fallow times, little if any research has focused on the dynamics of noncrop plant resources. In this paper, we use a data set of 26 fields of the same age, i.e., ~1.5 yr, but differing in the length and frequency of past fallow cycles, to examine the impact of shorter fallow periods on the availability of noncrop plant resources. The resources examined are collected in shifting cultivation fields by the Yucatec Maya in Quintana Roo, Mexico. These included firewood, which is cut from remnant trees and stumps spared at the time of felling, and 17 forage species that form part of the weed vegetation. Firewood showed an overall decrease in basal area with shorter fallow cycles, which was mostly related to the smaller diameter of the spared stumps and trees in short-fallow milpas. In contrast, forage species showed a mixed response. Species increasing in abundance in short-fallow milpas tended to be short-lived herbs and shrubs often with weedy habits, whereas those declining in abundance were predominantly pioneer trees and animal-dispersed species. Coppicing tree species showed a neutral response to fallow intensity. Within the cultural and ecological context of our study area, we expect that declines in firewood availability will be most significant for livelihoods because of the high reliance on firewood for local fuel needs and the fact that the main alternative source of firewood, forest

  13. Using prediction uncertainty analysis to design hydrologic monitoring networks: Example applications from the Great Lakes water availability pilot project

    Science.gov (United States)

    Fienen, Michael N.; Doherty, John E.; Hunt, Randall J.; Reeves, Howard W.

    2010-01-01

    The importance of monitoring networks for resource-management decisions is becoming more recognized, in both theory and application. Quantitative computer models provide a science-based framework to evaluate the efficacy and efficiency of existing and possible future monitoring networks. In the study described herein, two suites of tools were used to evaluate the worth of new data for specific predictions, which in turn can support efficient use of resources needed to construct a monitoring network. The approach evaluates the uncertainty of a model prediction and, by using linear propagation of uncertainty, estimates how much uncertainty could be reduced if the model were calibrated with addition information (increased a priori knowledge of parameter values or new observations). The theoretical underpinnings of the two suites of tools addressing this technique are compared, and their application to a hypothetical model based on a local model inset into the Great Lakes Water Availability Pilot model are described. Results show that meaningful guidance for monitoring network design can be obtained by using the methods explored. The validity of this guidance depends substantially on the parameterization as well; hence, parameterization must be considered not only when designing the parameter-estimation paradigm but also-importantly-when designing the prediction-uncertainty paradigm.

  14. Resource availability and diet in Harpy Eagle breeding territories on the Xingu River, Brazilian Amazon

    Directory of Open Access Journals (Sweden)

    FH. Aguiar-Silva

    Full Text Available Abstract In the Tapajos-Xingu interfluve, one of the largest birds of prey, the Harpy Eagle, is under intense anthropogenic pressure due to historical and recent reductions in forest cover. We studied prey availability and use by Harpy Eagle on six breeding territories on the low- and mid-Xingu River, between 2013 and 2015. We evaluated food resource availability using the environmental-surveys database from two methods: terrestrial surveys (RAPELD method and fauna rescue/flushing before vegetation suppression for the Belo Monte Hydroelectric Complex construction. Harpy Eagle diet was identified by prey remains sampled around six nest trees. Eighteen species of mammals, birds and reptiles comprised the prey items. Most prey species were sloths, primates and porcupines, which have arboreal habits and are found in forested areas, but two species, hoatzin and iguana, are usually associated with riverine habitats. The proportion of prey from each species predated on the nest best studied was different from estimated availability (χ2 = 54.23; df = 16; p < 0.001, however there was a positive correlation (rs = 0.7; p < 0.01 between prey species consumed and abundance available, where the predation was more on species more abundant. Continuous monitoring of the Harpy Eagle diet at these nests could evidence changes in the assemblage of prey species available for Harpy Eagles, due to changes in the seasonal flood pulse of the Xingu River to be caused by the operation of the hydroelectric dam, and changes in habitat features by forest reduction around breeding territories. We believe that it is important to consider the protection of remnants of forested areas in the landscape matrix surrounding the breeding territories to maintain the food resource availability and allow all pairs to successfully reproduce.

  15. Media access control and resource allocation for next generation passive optical networks

    CERN Document Server

    Ansari, Nirwan

    2013-01-01

    This book focuses on various Passive optical networks (PONs)  types, including currently deployed Ethernet PON (EPON) and Gigabit PON (GPON) as well as next generation WDM PON and OFDM PON. Also this book examines the integrated optical and wireless access networks. Concentrating on two issues in these networks: media access control (MAC) and resource allocation. These two problems can greatly affect performances of PONs such as network resource utilization and QoS of end users. Finally this book will discuss various solutions to address the MAC and resource allocation issues in various PON networks.

  16. Dynamic Resource Management in 802.11 Wireless Mesh Networks

    Directory of Open Access Journals (Sweden)

    George Athanasiou

    2012-01-01

    Full Text Available The association/handoff procedures are important components in a balanced operation of 802.11-based wireless mesh networks. In this paper, we introduce the concept of cooperative association where the stations (STA can share useful information in order to improve the performance of the association/reassociation procedures. Furthermore, in this work we introduce a load balancing mechanism that can be applied in mesh networks. This mechanism operates in a cross-layer manner taking into account uplink and downlink channel information, routing information, and congestion-based information. Our load balancing mechanism is based on a fairness index that is measured at each access point (AP neighborhood. This index reflects the way the communication load is shared in the neighboring APs. The iterative heuristic algorithms that we propose controls the communication load of each mesh AP in a distributed manner. We evaluate the performance of our mechanisms through OPNET simulations.

  17. Resource allocation for downlink multiuser video transmission over wireless lossy networks.

    Science.gov (United States)

    Maani, Ehsan; Pahalawatta, Peshala V; Berry, Randall; Pappas, Thrasyvoulos N; Katsaggelos, Aggelos K

    2008-09-01

    Demand for multimedia services, such as video streaming over wireless networks, has grown dramatically in recent years. The downlink transmission of multiple video sequences to multiple users over a shared resource-limited wireless channel, however, is a daunting task. Among the many challenges in this area are the time-varying channel conditions, limited available resources, such as bandwidth and power, and the different transmission requirements of different video content. This work takes into account the time-varying nature of the wireless channels, as well as the importance of individual video packets, to develop a cross-layer resource allocation and packet scheduling scheme for multiuser video streaming over lossy wireless packet access networks. Assuming that accurate channel feedback is not available at the scheduler, random channel losses combined with complex error concealment at the receiver make it impossible for the scheduler to determine the actual distortion of the sequence at the receiver. Therefore, the objective of the optimization is to minimize the expected distortion of the received sequence, where the expectation is calculated at the scheduler with respect to the packet loss probability in the channel. The expected distortion is used to order the packets in the transmission queue of each user, and then gradients of the expected distortion are used to efficiently allocate resources across users. Simulations show that the proposed scheme performs significantly better than a conventional content-independent scheme for video transmission.

  18. Optimal Incentive Pricing on Relaying Services for Maximizing Connection Availability in Multihop Cellular Networks

    Directory of Open Access Journals (Sweden)

    Ming-Hua Lin

    2012-01-01

    Full Text Available This paper investigates an incentive pricing problem for relaying services in multihop cellular networks. Providing incentives to encourage mobile nodes to relay data is a critical factor in building successful multihop cellular networks. Most existing approaches adopt fixed-rate or location-based pricing on rewarding packets forwarding. This study applies a mathematical programming model to determine an optimal incentive price for each intermediate node that provides relaying services. Under the obtained incentive price, the connection availability of the networks is maximized by using the same relaying costs as other pricing schemes. A signomial geometric programming problem is constructed, and a deterministic optimization approach is employed to solve the problem. Besides, quality-of-service constraints are added in the proposed model to mitigate the unfairness between connection availabilities of individual nodes. Computational results demonstrate that the proposed model obtains the optimal incentive price on relaying services to maximize connection availability of the networks.

  19. KEY ISSUES OF CONCEPTS' FORMATION OF THE NETWORK OF RESOURCE CENTER OF DISTANCE EDUCATION OF GENERAL EDUCATION INSTITUTIONS

    Directory of Open Access Journals (Sweden)

    Yuriy M. Bogachkov

    2013-06-01

    Full Text Available In the article the problem of constructing a network of resource centers for Distance Education to meet the needs of general secondary schools is presented. Modern educational trends in the use of Internet services in education are viewed.  Main contradictions, solution of which helps to create a network of resource centers, are identified. The definition of key terms related to the range of issues are given. The basic categories of participants, who  implementation of e-learning and networking are oriented on. There are considered the basic tasks of  distance education resource centers' functioning and types of supporting: personnel, regulatory, informative, systematic and  technical etc. The review of possible models of implementation of  students' distance education is reviewed . Three options for business models of resource centers, depending on funding  sources are offered.

  20. Multiuser Radio Resource Allocation for Multiservice Transmission in OFDMA-Based Cooperative Relay Networks

    Directory of Open Access Journals (Sweden)

    Zhang Xing

    2009-01-01

    Full Text Available Abstract The problem of multiservice transmission in OFDMA-based cooperative relay networks is studied comprehensively. We propose a framework to adaptively allocate power, subcarriers, and data rate in OFDMA system to maximize spectral efficiency under the constraints of satisfying multiuser multiservices' QoS requirements. Specifically, first we concentrate on the single-user scenario which considers multiservice transmission in point-to-point cooperative relay network. Based on the analysis of single-user scenario, we extend the multiservice transmission to multiuser point-to-multipoint scenario. Next, based on the framework, we propose several suboptimal radio resource allocation algorithms for multiservice transmissions in OFDMA-based cooperative relay networks to further reduce the computational complexity. Simulation results show that the proposed algorithms yield much higher spectral efficiency and much lower outage probability, which are flexible and efficient for the OFDMA-based cooperative relay system.

  1. The role of habitat complexity in community development is mediated by resource availability.

    Directory of Open Access Journals (Sweden)

    Rachel S Smith

    Full Text Available Habitat complexity strongly affects the structure and dynamics of ecological communities, with increased complexity often leading to greater species diversity and abundance. However, habitat complexity changes as communities develop, and some species alter their environment to themselves provide habitat for other species. Most experimental studies manipulate basal substrate complexity, and while the importance of complexity likely changes during community development, few studies have examined the temporal dynamics of this variable. We used two experiments to quantify the importance of basal substrate complexity to sessile marine invertebrate community development through space and time. First, we compared effects of substrate complexity at 70 sites across ten estuaries. Sites differed in recruitment and community development rates, and after three months provided spatial variation in community development stage. Second, we tested for effects of substrate complexity at multiple times at a single site. In both experiments, complexity affected marine sessile invertebrate community composition in the early stages of community development when resource availability was high. Effects of complexity diminished through time as the amount of available space (the primary limiting resource declined. Our work suggests the presence of a bare-space threshold, at which structural complexity of the basal substrate is overwhelmed by secondary biotic complexity. This threshold will be met at different times depending on local recruitment and growth rates and is likely to vary with productivity gradients.

  2. The effects of working memory resource availability on prospective memory: a formal modeling approach.

    Science.gov (United States)

    Smith, Rebekah E; Bayen, Ute J

    2005-01-01

    The PAM theory of event-based prospective memory (Smith, 2003; Smith & Bayen, 2004a) proposes that successful prospective memory performance demands upon the interaction of preparatory attentional processes and retrospective memory processes. The two experiments in the current study represent the first application of a formal model to investigate the sensitivity of these underlying processes to variations in working memory resource availability. Multinomial modeling of data from prospective-memory tasks showed that working memory span influenced preparatory attentional processes and retrospective-memory processes.

  3. Availability, usage, and threats to freshwater resources on low carbonate islands in Micronesia

    Science.gov (United States)

    Taboroši, Danko; Jenson, John W.; Sánchez Collazo, Maricruz; Zega, Mojca

    2010-05-01

    Federated States of Micronesia (FSM) is an insular nation in the western Pacific. It consists of 4 high volcanic islands and 37 low carbonate units, mostly coral atolls. The high islands are relatively large, and are developing socioeconomic centers of the country, whereas low islands are small and remote outposts of traditional subsistence lifestyle. The latter are inhabited by a fifth of the nation's population of 107,000 people. Total land area of a typical low island is a fraction of a km2, yet may be home to hundreds of people, creating some of the highest population densities in the Pacific. The resultant extreme pressures on natural resources are exacerbated by severe weather hazards, especially typhoons and unusually high tides which have recently flooded some islands in entirety, damaging homes and food sources. Freshwater resources are particularly sensitive. Crowded low islands have some of the world's most unfavorable relationships between population density and freshwater availability. As there are no communal or municipal facilities and government operated infrastructure, people have only two sources of water available for consumption: rainwater and groundwater. Rain is captured by individual households' thatch or corrugated iron roofs and transferred by gutters to concrete or fiberglass tanks. It is used for drinking, cooking, and dishwashing, and depending on availability, for laundry and showering. Such arrangement are highly unreliable, because they depend on sufficient rainfall and islanders' ability to capture and store it. Some communities have actually run out of water in the past, as a result of prolonged droughts or typhoons' damage to the catchment systems. In addition, tropical climate and pervasive organic matter and microorganisms make the tanks' maintenance difficult, because even most conscientious cleaning cannot ensure that stored water remains potable. Stomach problems and more serious health complications are common. Groundwater

  4. Social Networks and the Management of Water Resources for Agriculture in Rio Caia Catchment (Portugal

    Directory of Open Access Journals (Sweden)

    Nelson Lourenço

    2011-02-01

    Full Text Available The involvement of local people in the management of scarce resources, such as water available for agriculture, is a desirable approach to address some of the difficulties in the decision-making processes. This paper reports the experience of a research team of sociologists and geographers involved in the MULINO project (Multi-sectoral, Integrated and Operational decision support system for sustainable use of water resources at the catchment scale. In the framework of this international and interdisciplinary project, a social network analysis was developed in a catchment of south Portugal. This analysis was structured in five fundamental steps: Stakeholder Identification; Data Collection; Data Treatment; Network Visualisation; and Local Network Analysis. The information was gathered mainly through a questionnaire, bibliographic references, statistical inputs and field observations. In order to obtain a typology of stakeholders and their interactions, a factorial analysis of multiple correspondences and a cluster analysis were applied. The social network analysis, which is the measuring and visualisation of relationships and flows between people, groups, organisations or other information/knowledge processing entities, supported the description of two types of patterns that link different sets of actors: social groups (sets of actors closely linked together and social positions (sets of actors who are linked into the overall social system in similar ways. The analysis of the Caia Catchment network shows that this type of analysis is important not only as a means to characterising certain parameters about the network’s characteristics, but also as a significant tool to help improve the communication within the social network.

  5. Social Networks and the Management of Water Resources for Agriculture in Rio Caia Catchment (Portugal

    Directory of Open Access Journals (Sweden)

    Nelson Lourenço

    2006-12-01

    Full Text Available The involvement of local people in the management of scarce resources, such as water available for agriculture, is a desirable approach to address some of the difficulties in the decision-making processes. This paper reports the experience of a research team of sociologists and geographers involved in the MULINO project (Multi-sectoral, Integrated and Operational decision support system for sustainable use of water resources at the catchment scale. In the framework of this international and interdisciplinary project, a social network analysis was developed in a catchment of south Portugal. This analysis was structured in five fundamental steps: Stakeholder Identification; Data Collection; Data Treatment; Network Visualisation; and Local Network Analysis. The information was gathered mainly through a questionnaire, bibliographic references, statistical inputs and field observations. In order to obtain a typology of stakeholders and their interactions, a factorial analysis of multiple correspondences and a cluster analysis were applied. The social network analysis, which is the measuring and visualisation of relationships and flows between people, groups, organisations or other information/knowledge processing entities, supported the description of two types of patterns that link different sets of actors: social groups (sets of actors closely linked together and social positions (sets of actors who are linked into the overall social system in similar ways. The analysis of the Caia Catchment network shows that this type of analysis is important not only as a means to characterising certain parameters about the network’s characteristics, but also as a significant tool to help improve the communication within the social network.

  6. A Categorized Resource Sharing Mechanism for Device-to-Device Communications in Cellular Networks

    Directory of Open Access Journals (Sweden)

    Jie Chen

    2016-01-01

    Full Text Available Device-to-Device (D2D communications are considered one of the key technologies for 5G wireless communication systems. In this paper, a resource sharing mechanism, which applies different policies for different cases (thus being categorized, is proposed. In this scheme, all D2D pairs are divided into three groups by comparing the minimum transmit power with the maximum transmit power of each cellular UE. The proposed mechanism enables multiple D2D pairs in the second group to share the resource with cellular user equipment (UE simultaneously, by adjusting the transmit powers of these D2D transmitters. At the same time, D2D pairs in the first group and the third group share resource with cellular UE based on the transmit power minimization principle. Simulation results show that the proposed scheme can achieve relatively higher network throughput and lower transmit power consumption of the D2D system.

  7. Efficient Radio Resource Allocation in a GSM and GPRS Cellular Network

    Directory of Open Access Journals (Sweden)

    David Vannucci

    2004-10-01

    Full Text Available This paper investigates the effect of various radio resource allocation strategies in a GSM/GPRS cellular network. The most efficient resource allocation is analysed as a function of the proportion of circuit switched voice and packet switched data load. The Grade of Service and average packet delay is investigated as a function of the load, packet size and call duration. Additionally, the feasibility of using voice over Internet Protocol as opposed to circuit switched voice is investigated as a means to increase subscriber capacity per base station. The work is motivated firstly by the complexity of having both circuit switched and packet switched connectivity on GSM/GPRS mobile cellular system and secondly that an exclusively packet based access on GSM/GPRS has the potential to increase the efficiency of resource utilisation by suitably varying the channel allocation to exploit the characteristics of voice and data traffic.

  8. Market Model for Resource Allocation in Emerging Sensor Networks with Reinforcement Learning

    Directory of Open Access Journals (Sweden)

    Yue Zhang

    2016-11-01

    Full Text Available Emerging sensor networks (ESNs are an inevitable trend with the development of the Internet of Things (IoT, and intend to connect almost every intelligent device. Therefore, it is critical to study resource allocation in such an environment, due to the concern of efficiency, especially when resources are limited. By viewing ESNs as multi-agent environments, we model them with an agent-based modelling (ABM method and deal with resource allocation problems with market models, after describing users’ patterns. Reinforcement learning methods are introduced to estimate users’ patterns and verify the outcomes in our market models. Experimental results show the efficiency of our methods, which are also capable of guiding topology management.

  9. Classifying Vertical Wind Speed Profiles for Offshore Wind Resource and Available Power Assessment

    Science.gov (United States)

    St Pe, A.; Tippet, S.; Rabenhorst, S. D.; Delgado, R.

    2016-12-01

    Prior to offshore wind farm construction, an accurate estimate of preconstruction energy yield is required to optimize wind farm layout and justify the project's economic viability. Unfortunately, uncertainties exist during this stage due in-part to limited measurements to characterize the offshore wind resource and related uncertainties predicting a turbine's available power. To better understand these preconstruction energy yield uncertainties, Doppler wind lidar and other met-ocean measurements were collected offshore within Maryland's Wind Energy Area from July-August 2013. Given the diversity of vertical wind speed profile (VWP) observations, VWPs are classified based on the goodness-of-fit to several mathematical expressions. Results demonstrate on average VWP typevariability is related to the magnitude of hub-height (100m) wind speed and wind direction (i.e. offshore fetch), as power law, logarithmic-like, VWPs occur during slightly weaker, northeasterly flow, while more unexpected VWPs are associated with stronger, southwesterly flow, from land to sea. In addition, compared to power-law VWP classes, unexpected VWPs types demonstrate slightly warmer air and SSTs, as well as stable surface conditions. Classifying VWPs also provides a useful tool for relating preconstruction offshore wind resource and turbine available power uncertainties. Using an NREL 5MW offshore reference turbine's power curve, buoy extrapolated surface wind to hub-height (100m), lidar measured hub-height, and several Rotor Equivalent Wind (REW) available power estimates are compared. On average, traditional hub-height wind speed power yields the highest available power estimate, approximately 9-70 percent greater than other techniques. Further, unexpected VWPs demonstrate the greatest variability in critical superimposed meteorological controls known to impact turbine performance, thus yield greatest deviation from hub-height power and uncertainty between available power estimates

  10. Physicians' views on resource availability and equity in four European health care systems

    Directory of Open Access Journals (Sweden)

    Slowther Anne-Marie

    2007-08-01

    Full Text Available Abstract Background In response to limited resources, health care systems have adopted diverse cost-containment strategies and give priority to differing types of interventions. The perception of physicians, who witness the effects of these strategies, may provide useful insights regarding the impact of system-wide priority setting on access to care. Methods We conducted a cross-sectional survey to ascertain generalist physicians' perspectives on resources allocation and its consequences in Norway, Switzerland, Italy and the UK. Results Survey respondents (N = 656, response rate 43% ranged in age from 28–82, and averaged 25 years in practice. Most respondents (87.7% perceived some resources as scarce, with the most restrictive being: access to nursing home, mental health services, referral to a specialist, and rehabilitation for stroke. Respondents attributed adverse outcomes to scarcity, and some respondents had encountered severe adverse events such as death or permanent disability. Despite universal coverage, 45.6% of respondents reported instances of underinsurance. Most respondents (78.7% also reported some patient groups as more likely than others to be denied beneficial care on the basis of cost. Almost all respondents (97.3% found at least one cost-containment policy acceptable. The types of policies preferred suggest that respondents are willing to participate in cost-containment, and do not want to be guided by administrative rules (11.2% or restrictions on hospital beds (10.7%. Conclusion Physician reports can provide an indication of how organizational factors may affect availability and equity of health care services. Physicians are willing to participate in cost-containment decisions, rather than be guided by administrative rules. Tools should be developed to enable physicians, who are in a unique position to observe unequal access or discrimination in their health care environment, to address these issues in a more targeted way.

  11. A Fair Resource Allocation Algorithm for Data and Energy Integrated Communication Networks

    Directory of Open Access Journals (Sweden)

    Qin Yu

    2016-01-01

    Full Text Available With the rapid advancement of wireless network technologies and the rapid increase in the number of mobile devices, mobile users (MUs have an increasing high demand to access the Internet with guaranteed quality-of-service (QoS. Data and energy integrated communication networks (DEINs are emerging as a new type of wireless networks that have the potential to simultaneously transfer wireless energy and information via the same base station (BS. This means that a physical BS is virtualized into two parts: one is transferring energy and the other is transferring information. The former is called virtual energy base station (eBS and the latter is named as data base station (dBS. One important issue in such setting is dynamic resource allocation. Here the resource concerned includes both power and time. In this paper, we propose a fair data-and-energy resource allocation algorithm for DEINs by jointly designing the downlink energy beamforming and a power-and-time allocation scheme, with the consideration of finite capacity batteries at MUs and power sensitivity of radio frequency (RF to direct current (DC conversion circuits. Simulation results demonstrate that our proposed algorithm outperforms the existing algorithms in terms of fairness, beamforming design, sensitivity, and average throughput.

  12. An Enhanced OFDM Resource Allocation Algorithm in C-RAN Based 5G Public Safety Network

    Directory of Open Access Journals (Sweden)

    Lei Feng

    2016-01-01

    Full Text Available Public Safety Network (PSN is the network for critical communication when disaster occurs. As a key technology in 5G, Cloud-Radio Access Network (C-RAN can play an important role in PSN instead of LTE-based RAN. This paper firstly introduces C-RAN based PSN architecture and models the OFDM resource allocation problem in C-RAN based PSN as an integer quadratic programming, which allows the trade-off between expected bitrates and allocating fairness of PSN Service User (PSU. However, C-RAN based PSN needs to improve the efficiency of allocating algorithm because of a mass of PSU-RRH associations when disaster occurs. To deal with it, the resources allocating problem with integer variables is relaxed into one with continuous variables in the first step and an algorithm based on Generalized Bender’s Decomposition (GBD is proposed to solve it. Then we use Feasible Pump (FP method to get a feasible integer solution on the original OFDM resources allocation problem. The final experiments show the total throughput achieved by C-RAN based PSN is at most higher by 19.17% than the LTE-based one. And the average computational time of the proposed GBD and FP algorithm is at most lower than Barrier by 51.5% and GBD with no relaxation by 30.1%, respectively.

  13. Analysis of route availability in inter-working multi-hop wireless networks

    CSIR Research Space (South Africa)

    Salami, O

    2009-07-01

    Full Text Available In order to link a source-destination node pair in inter-working multi-hop wireless networks, links or routes must first be available. It is only after establishing the availability of links and routes between nodes that factors which affect...

  14. 76 FR 19784 - Notice of Availability of the Draft Environmental Impact Statement and Draft Resource Management...

    Science.gov (United States)

    2011-04-08

    ... Resource Management Plan Amendment to the 1987 Jarbidge Resource Management Plan for the Proposed China... prepared a Draft Environmental Impact Statement (EIS) and a Draft Resource Management Plan (RMP) Amendment... is not in conformance with the 1987 Jarbidge RMP provisions regarding Visual Resource Management (VRM...

  15. A Framework for Joint Optical-Wireless Resource Management in Multi-RAT, Heterogeneous Mobile Networks

    DEFF Research Database (Denmark)

    Zakrzewska, Anna; Popovska Avramova, Andrijana; Christiansen, Henrik Lehrmann

    2013-01-01

    to be always connected to a high-quality service (high bit rates, low latency), thus causing a very complex network control task from an operator’s point of view. We thus propose a framework allowing joint overall network resource management. This scheme covers different types of network heterogeneity (multi......Mobile networks are constantly evolving: new Radio Access Technologies (RATs) are being introduced, and backhaul architectures like Cloud-RAN (C-RAN) and distributed base stations are being proposed. Furthermore, small cells are being deployed to enhance network capacity. The end-users wish......-RAT, multi-layer, multi-architecture) by introducing a novel, hierarchical approach to network resource management. Self-Organizing Networks (SON) and cognitive network behaviors are covered as well as more traditional mobile network features. The framework is applicable to all phases of network operation...

  16. 78 FR 59713 - Notice of Availability of the North Dakota Greater Sage-Grouse Draft Resource Management Plan...

    Science.gov (United States)

    2013-09-27

    ... Bureau of Land Management Notice of Availability of the North Dakota Greater Sage-Grouse Draft Resource... Bureau of Land Management (BLM) has prepared a North Dakota Greater Sage-Grouse (GRSG) Draft Resource... management decisions for resources are described in the North Dakota RMP (1988). The planning area includes...

  17. 78 FR 17714 - Notice of Availability of the HiLine District Draft Resource Management Plan and Draft...

    Science.gov (United States)

    2013-03-22

    ... Bureau of Land Management Notice of Availability of the HiLine District Draft Resource Management Plan... Land Management (BLM) has prepared a Draft Resource Management Plan (RMP) and Draft Environmental... development. Other Restrictions: Avoidance area for rights-of-way, managed as Visual Resource Management (VRM...

  18. 75 FR 55345 - Notice of Availability of Record of Decision for the Socorro Field Office Resource Management...

    Science.gov (United States)

    2010-09-10

    ... Resource Management Plan/Environmental Impact Statement, New Mexico AGENCY: Bureau of Land Management... availability of the Record of Decision (ROD)/Approved Resource Management Plan (RMP) for the Socorro Field... Resource Management Plan Amendment (RMPA) and supporting NEPA analysis to further address this area's...

  19. 77 FR 23747 - Notice of Availability of the Proposed John Day Basin Resource Management Plan and Final...

    Science.gov (United States)

    2012-04-20

    ... Bureau of Land Management Notice of Availability of the Proposed John Day Basin Resource Management Plan... Proposed Resource Management Plan (RMP)/Final Environmental Impact Statement (EIS) for the John Day Basin... parties on the John Day Basin Resource Management Plan (RMP) mailing list. Copies of the Proposed RMP...

  20. 78 FR 15041 - Notice of Availability of the Draft Miles City Resource Management Plan and Environmental Impact...

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    2013-03-08

    ... Bureau of Land Management Notice of Availability of the Draft Miles City Resource Management Plan and... draft Resource Management Plan (RMP) revision and draft Environmental Impact Statement (EIS) for the... analyze and update public land and resource management objectives within the planning area. The planning...

  1. 75 FR 4842 - Notice of Availability of Record of Decision for the Yuma Field Office Resource Management Plan...

    Science.gov (United States)

    2010-01-29

    ... Bureau of Land Management Notice of Availability of Record of Decision for the Yuma Field Office Resource... (ROD)/Approved Resource Management Plan (RMP) for the Yuma Field Office (YFO) located in Arizona and... Designations Management section of the Approved RMP. The Preferred Alternative in the Draft Resource Management...

  2. Variations in the Availability of Pollen Resources Affect Honey Bee Health.

    Directory of Open Access Journals (Sweden)

    Garance Di Pasquale

    Full Text Available Intensive agricultural systems often expose honey bees (Apis mellifera L. to large temporal variations in the availability (quantity, quality and diversity of nutritional resources. Such nutritional irregularity is expected to affect honey bee health. We therefore tested under laboratory conditions the effect of such variation in pollen availability on honey bee health (survival and nursing physiology-hypopharyngeal gland development and vitellogenin expression. We fed honey bees with different diets composed of pollen pellets collected by honey bees in an agricultural landscape of western France. Slight drops (5-10% in the availability of oilseed rape (Brassica napus L. pollen resulted in significant reductions of all tested variables. Despite some variations in taxonomic diversity and nutritional quality, the pollen mixes harvested over the season had a similar positive influence on honey bee health, except for the one collected in late July that induced poor survival and nursing physiology. This period coincided with the mass-flowering of maize (Zea mays L., an anemophilous crop which produces poor-quality pollen. Therefore, changes in bee health were not connected to variations in pollen diversity but rather to variations in pollen depletion and quality, such as can be encountered in an intensive agricultural system of western France. Finally, even though pollen can be available ad libitum during the mass-flowering of some crops (e.g. maize, it can fail to provide bees with diet adequate for their development.

  3. Pulmonary rehabilitation in COPD – available resources and utilization in Swedish primary and secondary care

    Directory of Open Access Journals (Sweden)

    Sundh J

    2017-06-01

    Full Text Available Josefin Sundh,1 Helena Lindgren,2 Mikael Hasselgren,2 Scott Montgomery,3–5 Christer Janson,6 Björn Ställberg,7 Karin Lisspers7 1Department of Respiratory Medicine, School of Medical Sciences, 2Medical Programme, School of Medical Sciences, 3Clinical Epidemiology and Biostatistics, School of Medical Sciences, Örebro University, Örebro, 4Clinical Epidemiology Unit, Department of Medicine, Karolinska Institutet, Stockholm, Sweden; 5Department of Epidemiology and Public Health, University College, London, UK; 6Department of Medical Sciences, Respiratory, Allergy and Sleep Research, 7Department of Public Health and Caring Science, Family Medicine and Preventive Medicine, Uppsala University, Uppsala, Sweden Introduction: Pulmonary rehabilitation is effective in all stages of COPD. The availability and utilization of pulmonary rehabilitation resources, and the characteristics of COPD patients receiving rehabilitation, were investigated in primary and secondary care in central Sweden. Materials and methods: Data on available pulmonary rehabilitation resources were collected using questionnaires, to 14 hospitals and 54 primary health care centers, and information on utilization of different rehabilitation professionals was obtained from questionnaires completed by 1,329 COPD patients from the same centers. Multivariable logistic regression examined associations with having received rehabilitation in the previous year. Results: In primary care, nurse-based asthma/COPD clinics were common (87%, with additional separate access to other rehabilitation professionals. In secondary care, rehabilitation was more often offered as part of a multidisciplinary teamwork (71%. In total, 36% of the patients met an asthma/COPD nurse in the previous year. Utilization was lower in primary than in secondary care for physiotherapists (7% vs 16%, occupational therapists (3% vs 10%, nutritionists (5% vs 13%, and counselors (1% vs 4%. A higher COPD Assessment Test score

  4. The construction of multimedia teaching resource base based on campus network

    Science.gov (United States)

    Yuan, Bin

    2017-03-01

    Multimedia teaching is the important embodiment of modern education, is an important approach to improve the quality of teaching. In the current environment, campus network construction and application of multimedia teaching resource must be combined with school practice, explore the resources integration of multimedia technology in the campus network environment, in order to realize the long-term development of higher education.

  5. Ohio Resource Network: Mobilizing Colleges and Universities to Benefit Business & Industry.

    Science.gov (United States)

    Ohio Board of Regents, Columbus.

    The Ohio Resource Network's potential usefulness to Ohio's businesses and industries are discussed. The network provides Ohio executives and managers the resources of 62 state-assisted colleges and universities. Faculty can assist business/industry in five types of applications: using the latest technology, increasing productivity, financial…

  6. Few Ant Species Play a Central Role Linking Different Plant Resources in a Network in Rupestrian Grasslands.

    Directory of Open Access Journals (Sweden)

    Fernanda V Costa

    Full Text Available Ant-plant associations are an outstanding model to study the entangled ecological interactions that structure communities. However, most studies of plant-animal networks focus on only one type of resource that mediates these interactions (e.g, nectar or fruits, leading to a biased understanding of community structure. New approaches, however, have made possible to study several interaction types simultaneously through multilayer networks models. Here, we use this approach to ask whether the structural patterns described to date for ant-plant networks hold when multiple interactions with plant-derived food rewards are considered. We tested whether networks characterized by different resource types differ in specialization and resource partitioning among ants, and whether the identity of the core ant species is similar among resource types. We monitored ant interactions with extrafloral nectaries, flowers, and fruits, as well as trophobiont hemipterans feeding on plants, for one year, in seven rupestrian grassland (campo rupestre sites in southeastern Brazil. We found a highly tangled ant-plant network in which plants offering different resource types are connected by a few central ant species. The multilayer network had low modularity and specialization, but ant specialization and niche overlap differed according to the type of resource used. Beyond detecting structural differences across networks, our study demonstrates empirically that the core of most central ant species is similar across them. We suggest that foraging strategies of ant species, such as massive recruitment, may determine specialization and resource partitioning in ant-plant interactions. As this core of ant species is involved in multiple ecosystem functions, it may drive the diversity and evolution of the entire campo rupestre community.

  7. Insect-flower interaction network structure is resilient to a temporary pulse of floral resources from invasive Rhododendron ponticum.

    Directory of Open Access Journals (Sweden)

    Erin Jo Tiedeken

    Full Text Available Invasive alien plants can compete with native plants for resources, and may ultimately decrease native plant diversity and/or abundance in invaded sites. This could have consequences for native mutualistic interactions, such as pollination. Although invasive plants often become highly connected in plant-pollinator interaction networks, in temperate climates they usually only flower for part of the season. Unless sufficient alternative plants flower outside this period, whole-season floral resources may be reduced by invasion. We hypothesized that the cessation of flowering of a dominant invasive plant would lead to dramatic, seasonal compositional changes in plant-pollinator communities, and subsequent changes in network structure. We investigated variation in floral resources, flower-visiting insect communities, and interaction networks during and after the flowering of invasive Rhododendron ponticum in four invaded Irish woodland sites. Floral resources decreased significantly after R. ponticum flowering, but the magnitude of the decrease varied among sites. Neither insect abundance nor richness varied between the two periods (during and after R. ponticum flowering, yet insect community composition was distinct, mostly due to a significant reduction in Bombus abundance after flowering. During flowering R. ponticum was frequently visited by Bombus; after flowering, these highly mobile pollinators presumably left to find alternative floral resources. Despite compositional changes, however, network structural properties remained stable after R. ponticum flowering ceased: generality increased, but quantitative connectance, interaction evenness, vulnerability, H'2 and network size did not change. This is likely because after R. ponticum flowering, two to three alternative plant species became prominent in networks and insects increased their diet breadth, as indicated by the increase in network-level generality. We conclude that network structure

  8. An Online Convex Optimization Approach to Proactive Network Resource Allocation

    Science.gov (United States)

    Chen, Tianyi; Ling, Qing; Giannakis, Georgios B.

    2017-12-01

    Existing approaches to online convex optimization (OCO) make sequential one-slot-ahead decisions, which lead to (possibly adversarial) losses that drive subsequent decision iterates. Their performance is evaluated by the so-called regret that measures the difference of losses between the online solution and the best yet fixed overall solution in hindsight. The present paper deals with online convex optimization involving adversarial loss functions and adversarial constraints, where the constraints are revealed after making decisions, and can be tolerable to instantaneous violations but must be satisfied in the long term. Performance of an online algorithm in this setting is assessed by: i) the difference of its losses relative to the best dynamic solution with one-slot-ahead information of the loss function and the constraint (that is here termed dynamic regret); and, ii) the accumulated amount of constraint violations (that is here termed dynamic fit). In this context, a modified online saddle-point (MOSP) scheme is developed, and proved to simultaneously yield sub-linear dynamic regret and fit, provided that the accumulated variations of per-slot minimizers and constraints are sub-linearly growing with time. MOSP is also applied to the dynamic network resource allocation task, and it is compared with the well-known stochastic dual gradient method. Under various scenarios, numerical experiments demonstrate the performance gain of MOSP relative to the state-of-the-art.

  9. State-of-the-art on Virtualization and Software Defined Networking for Efficient Resource Allocation on Multi-tenant 5G Networks

    Directory of Open Access Journals (Sweden)

    Tsirakis Christos

    2017-01-01

    Full Text Available Global data traffic explosion is expected to set stringent requirements for next generation networks in the next decades. Besides, very low latencies will have to be guaranteed for enabling new delay critical services. However, current Software Defined Networking (SDN solutions have limitations in terms of separating both data and control planes among tenants/operators, and the capability to adapt to new or changing requirements. Moreover, some virtualization schemes do not ensure isolation of resources and do not guarantee bandwidth across the entities. While some others fail to provide flexibility to the slices to customize the resource allocation across the users. Therefore, novel SDN and virtualization techniques should be implemented to realize the upcoming 5G network that will facilitate at least efficient resource allocation and multi-tenancy among the plethora of different requirements.

  10. Empirical Research on the Topological Properties of Internet+ Information Resources Network Nodes

    Directory of Open Access Journals (Sweden)

    Wu Bin

    2017-01-01

    Full Text Available The “Internet+” is the product of the Internet development, and its network topology isn’t the same as the traditional Internet. The relevance of the average daily visiting data and the daily page viewing data are studied empirically, the rich-club coefficient and the node access probability are redefined, and the topological entropy model to measure the degree of nodes information aggregation is built by using the entropy theory. The experimental results showed that the calculation model scaled the degree of information aggregation of the nodes in the “Internet+” topology efficiently. It provides an available computational model for the observation of resource access behaviors in the “Internet+” network.

  11. Variations in the Availability of Pollen Resources Affect Honey Bee Health.

    Science.gov (United States)

    Di Pasquale, Garance; Alaux, Cédric; Le Conte, Yves; Odoux, Jean-François; Pioz, Maryline; Vaissière, Bernard E; Belzunces, Luc P; Decourtye, Axel

    2016-01-01

    Intensive agricultural systems often expose honey bees (Apis mellifera L.) to large temporal variations in the availability (quantity, quality and diversity) of nutritional resources. Such nutritional irregularity is expected to affect honey bee health. We therefore tested under laboratory conditions the effect of such variation in pollen availability on honey bee health (survival and nursing physiology-hypopharyngeal gland development and vitellogenin expression). We fed honey bees with different diets composed of pollen pellets collected by honey bees in an agricultural landscape of western France. Slight drops (5-10%) in the availability of oilseed rape (Brassica napus L.) pollen resulted in significant reductions of all tested variables. Despite some variations in taxonomic diversity and nutritional quality, the pollen mixes harvested over the season had a similar positive influence on honey bee health, except for the one collected in late July that induced poor survival and nursing physiology. This period coincided with the mass-flowering of maize (Zea mays L.), an anemophilous crop which produces poor-quality pollen. Therefore, changes in bee health were not connected to variations in pollen diversity but rather to variations in pollen depletion and quality, such as can be encountered in an intensive agricultural system of western France. Finally, even though pollen can be available ad libitum during the mass-flowering of some crops (e.g. maize), it can fail to provide bees with diet adequate for their development.

  12. QoS-Oriented High Dynamic Resource Allocation in Vehicular Communication Networks

    Directory of Open Access Journals (Sweden)

    Tarek Bejaoui

    2014-01-01

    Full Text Available Vehicular ad hoc networks (VANETs are emerging as new research area and attracting an increasing attention from both industry and research communities. In this context, a dynamic resource allocation policy that maximizes the use of available resources and meets the quality of service (QoS requirement of constraining applications is proposed. It is a combination of a fair packet scheduling policy and a new adaptive QoS oriented call admission control (CAC scheme based on the vehicle density variation. This scheme decides whether the connection request is to be admitted into the system, while providing fair access and guaranteeing the desired throughput. The proposed algorithm showed good performance in testing in real world environment.

  13. End-to-End Availability Analysis of IMS-Based Networks

    DEFF Research Database (Denmark)

    Kamyod, Chayapol; Nielsen, Rasmus Hjorth; Prasad, Neeli R.

    2013-01-01

    Generation Networks (NGNs). In this paper, an end-to-end availability model is proposed and evaluated using a combination of Reliability Block Diagrams (RBD) and a proposed five-state Markov model. The overall availability for intra- and inter domain communication in IMS is analyzed, and the state...

  14. 78 FR 24154 - Notice of Availability of a National Animal Health Laboratory Network Reorganization Concept Paper

    Science.gov (United States)

    2013-04-24

    ... Plant Health Inspection Service is making available a concept paper that describes a revised structure... paper we are making available for comment presents a structure we believe will give the NAHLN increased... Network Reorganization Concept Paper AGENCY: Animal and Plant Health Inspection Service, USDA. ACTION...

  15. Diverse urban plantings managed with sufficient resource availability can increase plant productivity and arthropod diversity

    Directory of Open Access Journals (Sweden)

    Jonathon eMuller

    2014-10-01

    Full Text Available Buildings structures and surfaces are explicitly being used to grow plants, and these ‘urban plantings’ are typically designed for aesthetic value. Urban plantings also have the potential to contribute significant ‘ecological values’ by increasing urban habitat for animals such as arthropods and by increasing plant productivity. In this study, we evaluated how the provision of these additional ecological values is affected by plant species richness; the availability of essential resources for plants, such as water, light, space; and soil characteristics. We sampled 33 plantings located on the exterior of three buildings in the urban centre of Brisbane, Australia (subtropical climatic region over two, six week sampling periods characterised by different temperature and rainfall conditions. Plant cover was estimated as a surrogate for productivity as destructive sampling of biomass was not possible. We measured weekly light levels (photosynthetically active radiation, plant CO2 assimilation, soil CO2 efflux, and arthropod diversity.Differences in plant cover were best explained by a three-way interaction of plant species richness, management water regime and sampling period. As the richness of plant species increased in a planter, productivity and total arthropod richness also increased significantly - likely due to greater habitat heterogeneity and quality. Overall we found urban plantings can provide additional ecological values if essential resources are maintained within a planter such as water, light and soil temperature. Diverse urban plantings that are managed with these principles in mind can contribute to the attraction of diverse arthropod communities, and lead to increased plant productivity within a dense urban context.

  16. Evaluating the best available social science for natural resource management decision-making

    Science.gov (United States)

    Susan Charnley; Courtney Carothers; Terre Satterfield; Arielle Levine; Melissa R. Poe; Karma Norman; Jamie Donatuto; Sara Jo Breslow; Michael B. Mascia; Phillip S. Levin; Xavier Basurto; Christina C. Hicks; Carlos García-Quijano; Kevin St. Martin

    2017-01-01

    Increasing recognition of the human dimensions of natural resource management issues, and of social and ecological sustainability and resilience as being inter-related, highlights the importance of applying social science to natural resource management decision-making. Moreover, a number of laws and regulations require natural resource management agencies to consider...

  17. 77 FR 42758 - Notice of Availability of the Prehistoric Trackways National Monument Draft Resource Management...

    Science.gov (United States)

    2012-07-20

    ... Resource Management Plan and Draft Environmental Impact Statement, New Mexico AGENCY: Bureau of Land... Bureau of Land Management (BLM) has prepared a Draft Resource Management Plan (RMP) and Draft... continue existing management decisions; Alternative B, which would emphasize resource preservation and...

  18. Resource Availability Modulates the Cooperative and Competitive Nature of a Microbial Cross-Feeding Mutualism.

    Science.gov (United States)

    Hoek, Tim A; Axelrod, Kevin; Biancalani, Tommaso; Yurtsev, Eugene A; Liu, Jinghui; Gore, Jeff

    2016-08-01

    Mutualisms between species play an important role in ecosystem function and stability. However, in some environments, the competitive aspects of an interaction may dominate the mutualistic aspects. Although these transitions could have far-reaching implications, it has been difficult to study the causes and consequences of this mutualistic-competitive transition in experimentally tractable systems. Here, we study a microbial cross-feeding mutualism in which each yeast strain supplies an essential amino acid for its partner strain. We find that, depending upon the amount of freely available amino acid in the environment, this pair of strains can exhibit an obligatory mutualism, facultative mutualism, competition, parasitism, competitive exclusion, or failed mutualism leading to extinction of the population. A simple model capturing the essential features of this interaction explains how resource availability modulates the interaction and predicts that changes in the dynamics of the mutualism in deteriorating environments can provide advance warning that collapse of the mutualism is imminent. We confirm this prediction experimentally by showing that, in the high nutrient competitive regime, the strains rapidly reach a common carrying capacity before slowly reaching the equilibrium ratio between the strains. However, in the low nutrient regime, before collapse of the obligate mutualism, we find that the ratio rapidly reaches its equilibrium and it is the total abundance that is slow to reach equilibrium. Our results provide a general framework for how mutualisms may transition between qualitatively different regimes of interaction in response to changes in nutrient availability in the environment.

  19. A Markov model for evaluating resource sharing policies for DASH assisting network elements

    NARCIS (Netherlands)

    J.W.M. Kleinrouweler (Jan Willem); S. Cabrero Barros (Sergio); R.D. van der Mei (Rob); P.S. Cesar Garcia (Pablo Santiago)

    2016-01-01

    textabstractIn this paper, we present a model for evaluating bandwidth sharing policies, that can be applied to networks that handle both video streaming traffic, as well as other traffic. Video streaming is a demanding network application. In crowded networks, resources need to be properly divided

  20. A Markov model for evaluating resource sharing policies for DASH assisting network elements

    NARCIS (Netherlands)

    J.W.M. Kleinrouweler (Jan Willem); S. Cabrero Barros (Sergio); R.D. van der Mei (Rob); P.S. Cesar Garcia (Pablo Santiago)

    2017-01-01

    textabstractIn this paper, we present a model for evaluating bandwidth sharing policies, that can be applied to networks that handle both video streaming traffic, as well as other traffic. Video streaming is a demanding network application. In crowded networks, resources need to be properly divided

  1. Empowering health personnel for decentralized health planning in India: The Public Health Resource Network

    Directory of Open Access Journals (Sweden)

    Prasad Vandana

    2009-07-01

    Full Text Available Abstract The Public Health Resource Network is an innovative distance-learning course in training, motivating, empowering and building a network of health personnel from government and civil society groups. Its aim is to build human resource capacity for strengthening decentralized health planning, especially at the district level, to improve accountability of health systems, elicit community participation for health, ensure equitable and accessible health facilities and to bring about convergence in programmes and services. The question confronting health systems in India is how best to reform, revitalize and resource primary health systems to deliver different levels of service aligned to local realities, ensuring universal coverage, equitable access, efficiency and effectiveness, through an empowered cadre of health personnel. To achieve these outcomes it is essential that health planning be decentralized. Districts vary widely according to the specific needs of their population, and even more so in terms of existing interventions and available resources. Strategies, therefore, have to be district-specific, not only because health needs vary, but also because people's perceptions and capacities to intervene and implement programmes vary. In centrally designed plans there is little scope for such adaptation and contextualization, and hence decentralized planning becomes crucial. To undertake these initiatives, there is a strong need for trained, motivated, empowered and networked health personnel. It is precisely at this level that a lack of technical knowledge and skills and the absence of a supportive network or adequate educational opportunities impede personnel from making improvements. The absence of in-service training and of training curricula that reflect field realities also adds to this, discouraging health workers from pursuing effective strategies. The Public Health Resource Network is thus an attempt to reach out to motivated

  2. A New Resource Allocation Protocol for the Backhaul of Underwater Cellular Wireless Networks

    Directory of Open Access Journals (Sweden)

    Changho Yun

    2018-01-01

    Full Text Available In this paper, an underwater base station initiating (UBSI resource allocation is proposed for underwater cellular wireless networks (UCWNs, which is a new approach to determine the backhaul capacity of underwater base stations (UBSs. This backhaul is a communication link from a UBS to a UBS controller (UBSC. Contrary to conventional resource allocation protocols, a UBS initiates to re-determine its backhaul capacity for itself according to its queue status; it releases a portion of its backhaul capacity in the case of experiencing resource under-utilization, and also requests additional backhaul capacity to the UBSC if packet drops are caused due to queue-overflow. This protocol can be appropriate and efficient to the underwater backhaul link where the transmission rate is quite low and the latency is unneglectable. In order to investigate the applicability of the UBSI resource allocation protocol to the UCWN, its performance is extensively analyzed via system level simulations. In our analysis, considered performance measures include average packet drop rate, average resource utilization, average message overhead, and the reserved capacity of the UBSC. In particular, the simulation results show that our proposed protocol not only utilizes most of the given backhaul capacity (more than 90 percent of resource utilization on the average, but also reduces controlling message overheads induced by resource allocation (less than 2 controlling messages on the average. It is expected that the simulation results and analysis in this paper can be used as operating guidelines to apply our new resource allocation protocol for the UCWN.

  3. Multilayer geospatial analysis of water availability for shale resources development in Mexico

    Science.gov (United States)

    Galdeano, C.; Cook, M. A.; Webber, M. E.

    2017-08-01

    Mexico’s government enacted an energy reform in 2013 that aims to foster competitiveness and private investment throughout the energy sector value chain. As part of this reform, it is expected that extraction of oil and gas via hydraulic fracturing will increase in five shale basins (e.g. Burgos, Sabinas, Tampico, Tuxpan, and Veracruz). Because hydraulic fracturing is a water-intensive activity, it is relevant to assess the potential water availability for this activity in Mexico. This research aims to quantify the water availability for hydraulic fracturing in Mexico and identify its spatial distribution along the five shale basins. The methodology consisted of a multilayer geospatial analysis that overlays the water availability in the watersheds and aquifers with the different types of shale resources areas (e.g. oil and associated gas, wet gas and condensate, and dry gas) in the five shale basins. The aquifers and watersheds in Mexico are classified in four zones depending on average annual water availability. Three scenarios were examined based on different impact level on watersheds and aquifers from hydraulic fracturing. For the most conservative scenario analyzed, the results showed that the water available could be used to extract between 8.15 and 70.42 Quadrillion British thermal units (Quads) of energy in the typical 20-30 year lifetime of the hydraulic fracturing wells that could be supplied with the annual water availability overlaying the shale areas, with an average across estimates of around 18.05 Quads. However, geographic variation in water availability could represent a challenge for extracting the shale reserves. Most of the water available is located closer to the Gulf of Mexico, but the areas with the larger recoverable shale reserves coincide with less water availability in Northern Mexico. New water management techniques (such as recycling and re-use), more efficient fracturing methods, shifts in usage patterns, or other water sources need

  4. Modulation of biodiversity-invasion relationships by resource availability : commensal species defend invaders in a changing world

    OpenAIRE

    Yang, T.

    2017-01-01

    Biological invasion brings disturbance to localenvironment, such as reducing available niches or altering species interactions. In order to reduce the undesired consequences brought by invasion, the determining factors suppressing invasion become important. The success of invasion depends on resident species and resource availability. Resident community with high species richness can better suppress invasion via intensive resource competition. Niche overlap between resident community and the ...

  5. Deadlock Avoidance Policy in Mobile Wireless Sensor Networks with Free Choice Resource Routing

    Directory of Open Access Journals (Sweden)

    Prasanna Ballal

    2008-09-01

    Full Text Available Efficient control schemes are required for effective cooperation of robot teams in a mobile wireless sensor network. If the robots (resources are also in charge of executing multiple simultaneous missions, then risks of deadlocks due to the presence of shared resources among different missions increase and have to be tackled. Discrete event control with deadlock avoidance has been used in the past for robot team coordination for the case of multi reentrant flowline models with shared resources. In this paper we present an analysis of deadlock avoidance for a generalized case of multi reentrant flow line systems (MRF called the Free Choice Multi Reentrant Flow Line systems (FMRF. In FMRF, some tasks have multiple resource choices; hence routing decisions have to be made and current results in deadlock avoidance for MRF do not hold. This analysis is based on the so-called Circular Waits (CW of the resources in the system. For FMRF, the well known notions of Critical Siphons and Critical Subsystems must be generalized and we redefine these objects for such systems. Our second contribution provides a matrix formulation that efficiently computes the objects required for deadlock avoidance in FMRF systems. A MAXWIP dispatching policy is formulated for deadlock avoidance in FMRF systems. According to this policy, deadlock in FMRF is avoided by limiting the work in progress (WIP in the critical subsystems of each CW. Implemented results of the proposed scheme in a WSN test-bed is presented in the paper.

  6. Deadlock Avoidance Policy in Mobile Wireless Sensor Networks with Free Choice Resource Routing

    Directory of Open Access Journals (Sweden)

    Prasanna Ballal

    2008-11-01

    Full Text Available Efficient control schemes are required for effective cooperation of robot teams in a mobile wireless sensor network. If the robots (resources are also in charge of executing multiple simultaneous missions, then risks of deadlocks due to the presence of shared resources among different missions increase and have to be tackled. Discrete event control with deadlock avoidance has been used in the past for robot team coordination for the case of multi reentrant flowline models with shared resources. In this paper we present an analysis of deadlock avoidance for a generalized case of multi reentrant flow line systems (MRF called the Free Choice Multi Reentrant Flow Line systems (FMRF. In FMRF, some tasks have multiple resource choices; hence routing decisions have to be made and current results in deadlock avoidance for MRF do not hold. This analysis is based on the so-called Circular Waits (CW of the resources in the system. For FMRF, the well known notions of Critical Siphons and Critical Subsystems must be generalized and we redefine these objects for such systems. Our second contribution provides a matrix formulation that efficiently computes the objects required for deadlock avoidance in FMRF systems. A MAXWIP dispatching policy is formulated for deadlock avoidance in FMRF systems. According to this policy, deadlock in FMRF is avoided by limiting the work in progress (WIP in the critical subsystems of each CW. Implemented results of the proposed scheme in a WSN test-bed is presented in the paper.

  7. New insights on resource stoichiometry: assessing availability of carbon, nitrogen, and phosphorus to bacterioplankton

    Science.gov (United States)

    Soares, Ana R. A.; Bergström, Ann-Kristin; Sponseller, Ryan A.; Moberg, Joanna M.; Giesler, Reiner; Kritzberg, Emma S.; Jansson, Mats; Berggren, Martin

    2017-03-01

    Boreal lake and river ecosystems receive large quantities of organic nutrients and carbon (C) from their catchments. How bacterioplankton respond to these inputs is not well understood, in part because we base our understanding and predictions on total pools, yet we know little about the stoichiometry of bioavailable elements within organic matter. We designed bioassays with the purpose of exhausting the pools of readily bioavailable dissolved organic carbon (BDOC), bioavailable dissolved nitrogen (BDN), and bioavailable dissolved phosphorus (BDP) as fast as possible. Applying the method in four boreal lakes at base-flow conditions yielded concentrations of bioavailable resources in the range 105-693 µg C L-1 for BDOC (2 % of initial total DOC), 24-288 µg N L-1 for BDN (31 % of initial total dissolved nitrogen), and 0.2-17 µg P L-1 for BDP (49 % of initial total dissolved phosphorus). Thus, relative bioavailability increased from carbon (C) to nitrogen (N) to phosphorus (P). We show that the main fraction of bioavailable nutrients is organic, representing 80 % of BDN and 61 % of BDP. In addition, we demonstrate that total C : N and C : P ratios are as much as 13-fold higher than C : N and C : P ratios for bioavailable resource fractions. Further, by applying additional bioavailability measurements to seven widely distributed rivers, we provide support for a general pattern of relatively high bioavailability of P and N in relation to C. Altogether, our findings underscore the poor availability of C for support of bacterial metabolism in boreal C-rich freshwaters, and suggest that these ecosystems are very sensitive to increased input of bioavailable DOC.

  8. Latvian health care competitiveness in relation to its infrastructure and available resources

    Directory of Open Access Journals (Sweden)

    Kokarevica A.

    2018-01-01

    Full Text Available Resources are one of the essential indicators for the functioning of the health care system. Better health care provision is an essential prerequisite for the export of services. Traditionally a competitive health care system is linked to a number of factors (price, quality, reliability, products and services largely determined by the new technologies, innovations and implementation the new methods. The authors of this article analyzed and collected data from the European Commission Eurostat and OECD data. Current situation in health care in Latvia is characterized by populations’ restricted access to health care services, high out-of-pocket payments and poor health outcomes of the population. More than 10% of Latvian population can’t afford medical care. The ratio of public funding for healthcare in Latvia is among the lowest in EU countries. Latvia spends 5.3% (USD PPP 1217 of GDP on health, lower than the OCED country average of 8.9% (USD PPP 3453. Latvia is facing a dramatic gap between the availability of hospital beds and long term care beds and the lowest prevalence of general medical practitioners among all Baltic States 321.6 per 100 000. These mentioned factors may hinder the development of health care in Latvia and reduce the ability to participate in international health service market.

  9. A Simple Dual Decomposition Method for Resource Allocation in Telecommunication Networks

    Directory of Open Access Journals (Sweden)

    Konnov Igor

    2016-01-01

    Full Text Available We consider a problem of optimal resource allocation in a wireless communication network divided into zones (clusters. The network manager aims to distribute some homogeneous resource (bandwidth among users of several zones in order to maximize the total network profit, which takes into account payments from users and implementation costs. As a result, we obtain a convex optimization problem involving capacity and balance constraints. By using the dual Lagrangian method with respect to the capacity constraint, we reduce the initial problem to a suitable one-dimensional problem, so that calculation of its cost function value leads to independent solution of zonal problems, treated as two-side auction models with one trader. We show that solution of each zonal problem can be found exactly by a simple arrangement type algorithm even in the case where the trader price is not fixed. Besides, we suggest ways to adjust the basic problem to the case of moving nodes. Some results of computational experiments confirm the applicability of the new method.

  10. Resource Allocation for Downlink Multi-Cell OFDMA Cognitive Radio Network Using Hungarian Method

    Directory of Open Access Journals (Sweden)

    N. Forouzan

    2013-12-01

    Full Text Available This paper considers the problem of resource allocation for downlink part of an OFDM-based multi-cell cognitive radio network which consists of multiple secondary transmitters and receivers communicating simultaneously in the presence of multiple primary users. We present a new framework to maximize the total data throughput of secondary users by means of subchannel assignment, while ensuring interference leakage to PUs is below a threshold. In this framework, we first formulate the resource allocation problem as a nonlinear and non-convex optimization problem. Then we represent the problem as a maximum weighted matching in a bipartite graph and propose an iterative algorithm based on Hungarian method to solve it. The present contribution develops an efficient subchannel allocation algorithm that assigns subchannels to the secondary users without the perfect knowledge of fading channel gain between cognitive radio transmitter and primary receivers. The performance of the proposed subcarrier allocation algorithm is compared with a blind subchannel allocation as well as another scheme with the perfect knowledge of channel-state information. Simulation results reveal that a significant performance advantage can still be realized, even if the optimization at the secondary network is based on imperfect network information.

  11. Estimation of distribution algorithm for resource allocation in green cooperative cognitive radio sensor networks.

    Science.gov (United States)

    Naeem, Muhammad; Pareek, Udit; Lee, Daniel C; Anpalagan, Alagan

    2013-04-12

    Due to the rapid increase in the usage and demand of wireless sensor networks (WSN), the limited frequency spectrum available for WSN applications will be extremely crowded in the near future. More sensor devices also mean more recharging/replacement of batteries, which will cause significant impact on the global carbon footprint. In this paper, we propose a relay-assisted cognitive radio sensor network (CRSN) that allocates communication resources in an environmentally friendly manner. We use shared band amplify and forward relaying for cooperative communication in the proposed CRSN. We present a multi-objective optimization architecture for resource allocation in a green cooperative cognitive radio sensor network (GC-CRSN). The proposed multi-objective framework jointly performs relay assignment and power allocation in GC-CRSN, while optimizing two conflicting objectives. The first objective is to maximize the total throughput, and the second objective is to minimize the total transmission power of CRSN. The proposed relay assignment and power allocation problem is a non-convex mixed-integer non-linear optimization problem (NC-MINLP), which is generally non-deterministic polynomial-time (NP)-hard. We introduce a hybrid heuristic algorithm for this problem. The hybrid heuristic includes an estimation-of-distribution algorithm (EDA) for performing power allocation and iterative greedy schemes for constraint satisfaction and relay assignment. We analyze the throughput and power consumption tradeoff in GC-CRSN. A detailed analysis of the performance of the proposed algorithm is presented with the simulation results.

  12. Auction-Based Resource Allocation for Cooperative Video Transmission Protocols over Wireless Networks

    Directory of Open Access Journals (Sweden)

    Zhu Han

    2009-01-01

    Full Text Available Cooperative transmission has been proposed as a novel transmission strategy that takes advantage of broadcast nature of wireless networks, forms virtual MIMO system, and provides diversity gains. In this paper, wireless video transmission protocols are proposed, in which the spectrum resources are first allocated for the source side to broadcast video packets to the relay and destination, and then for the relay side to transmit side information generated from the received packets. The proposed protocols are optimized to minimize the end-to-end expected distortion via choosing bandwidth/power allocation, configuration of side information, subject to bandwidth and power constraints. For multiuser cases, most of current resource allocation approaches cannot be naturally extended and applied to the networks with relay nodes for video transmission. This paper extends the share auction approach into the cooperative video communication scenarios and provides a near-optimal solution for resource allocation. Experimental results have demonstrated that the proposed approach has significant advantage of up to 4 dB gain in single user case and 1.3 dB gain in multiuser case over the reference systems in terms of peak-to-signal-noise ratio. In addition, it reduces the formidable computational complexity of the optimal solution to linear complexity with performance degradation of less than 0.3 dB.

  13. Resource management for multimedia services in high data rate wireless networks

    CERN Document Server

    Zhang, Ruonan; Pan, Jianping

    2017-01-01

    This brief offers a valuable resource on principles of quality-of-service (QoS) provisioning and the related link-layer resource management techniques for high data-rate wireless networks. The primary emphasis is on protocol modeling and analysis. It introduces media access control (MAC) protocols, standards of wireless local area networks (WLANs), wireless personal area networks (WPANs), and wireless body area networks (WBANs), discussing their key technologies, applications, and deployment scenarios. The main analytical approaches and models for performance analysis of the fundamental resource scheduling mechanisms, including the contention-based, reservation-based, and hybrid MAC, are presented. To help readers understand and evaluate system performance, the brief contains a range of simulation results. In addition, a thorough bibliography provides an additional tool. This brief is an essential resource for engineers, researchers, students, and users of wireless networks.

  14. [Availability of resources for patients with wet age-related macular degeneration. Optimal study].

    Science.gov (United States)

    Casaroli-Marano, R; Roura, M

    2013-08-01

    The aim of the study was to assess the availability of resources for patients with wet age-related macular degeneration (wAMD) in current clinical practice. Observational, cross-sectional and multicenter study. Eligible subjects were ≥ 18 years old, with primary/secondary active subfoveal AMD-related choroidal neovascularization diagnosed 12-18 months prior to inclusion in the study. A total of 266 patients were included (39 centers). The mean age (SD) was 76.1 (8.1) years, of whom 55.6% were female. According to the investigator assessment a median (Q1-Q3) of 20.0 (10.0-50.0) patients were visited weekly. A mean of 100.0 (45.0-250.0) were currently under treatment mainly performed in operating rooms (61.5%). Centers had 1.0 (1.0-2.0) operating rooms available for treatment 2.0 (2.0-5.0) days/week. In 74.4% they were located on different floors/buildings from ophthalmology services. Waiting time until visit was 40.0 (30.0-60.0) min, and duration of treatment was 20.0 (15.0-50.0) min. The time between request until medical visit was 20.0 (15.0-30.0) days, and from diagnosis to treatment was 7.0 (5.0-10.0) days. Clinicians considered there was insufficient staff for examinations (84.6%), and treatment (46.2%). About 30.8% and 20.5% mentioned lack of diagnostic tools, such as optical coherence tomography and fluorescein angiography. More resources for diagnosis and treatment of wAMD are required. These results, together with the current policy of reducing the budget in the Spanish Health System, could lead to possible delays in the diagnosis and treatment of wAMD. Copyright © 2012 Sociedad Española de Oftalmología. Published by Elsevier Espana. All rights reserved.

  15. Sustainable use of renewable resources in a stylized social-ecological network model under heterogeneous resource distribution

    Science.gov (United States)

    Barfuss, Wolfram; Donges, Jonathan F.; Wiedermann, Marc; Lucht, Wolfgang

    2017-04-01

    Human societies depend on the resources ecosystems provide. Particularly since the last century, human activities have transformed the relationship between nature and society at a global scale. We study this coevolutionary relationship by utilizing a stylized model of private resource use and social learning on an adaptive network. The latter process is based on two social key dynamics beyond economic paradigms: boundedly rational imitation of resource use strategies and homophily in the formation of social network ties. The private and logistically growing resources are harvested with either a sustainable (small) or non-sustainable (large) effort. We show that these social processes can have a profound influence on the environmental state, such as determining whether the private renewable resources collapse from overuse or not. Additionally, we demonstrate that heterogeneously distributed regional resource capacities shift the critical social parameters where this resource extraction system collapses. We make these points to argue that, in more advanced coevolutionary models of the planetary social-ecological system, such socio-cultural phenomena as well as regional resource heterogeneities should receive attention in addition to the processes represented in established Earth system and integrated assessment models.

  16. Logistics Mode and Network Planning for Recycle of Crop Straw Resources

    OpenAIRE

    Zhou, Lingyun; Gu, Weidong; Zhang, Qing

    2013-01-01

    To realize the straw biomass industrialized development, it should speed up building crop straw resource recycle logistics network, increasing straw recycle efficiency, and reducing straw utilization cost. On the basis of studying straw recycle process, this paper presents innovative concept and property of straw recycle logistics network, analyses design thinking of straw recycle logistics network, and works out straw recycle logistics mode and network topological structure. Finally, it come...

  17. AGI's Earth Science Week and Education Resources Network: Connecting Teachers to Geoscience Organizations and Classroom Resources that Support NGSS Implementation

    Science.gov (United States)

    Robeck, E.; Camphire, G.; Brendan, S.; Celia, T.

    2016-12-01

    There exists a wide array of high quality resources to support K-12 teaching and motivate student interest in the geosciences. Yet, connecting teachers to those resources can be a challenge. Teachers working to implement the NGSS can benefit from accessing the wide range of existing geoscience resources, and from becoming part of supportive networks of geoscience educators, researchers, and advocates. Engaging teachers in such networks can be facilitated by providing them with information about organizations, resources, and opportunities. The American Geoscience Institute (AGI) has developed two key resources that have great value in supporting NGSS implement in these ways. Those are Earth Science Week, and the Education Resources Network in AGI's Center for Geoscience and Society. For almost twenty years, Earth Science Week, has been AGI's premier annual outreach program designed to celebrate the geosciences. Through its extensive web-based resources, as well as the physical kits of posters, DVDs, calendars and other printed materials, Earth Science Week offers an array of resources and opportunities to connect with the education-focused work of important geoscience organizations such as NASA, the National Park Service, HHMI, esri, and many others. Recently, AGI has initiated a process of tagging these and other resources to NGSS so as to facilitate their use as teachers develop their instruction. Organizing Earth Science Week around themes that are compatible with topics within NGSS contributes to the overall coherence of the diverse array of materials, while also suggesting potential foci for investigations and instructional units. More recently, AGI has launched its Center for Geoscience and Society, which is designed to engage the widest range of audiences in building geoscience awareness. As part of the Center's work, it has launched the Education Resources Network (ERN), which is an extensive searchable database of all manner of resources for geoscience

  18. Application of Bayesian Decision Networks for sustainable groundwater resources management in semi-arid regions

    Science.gov (United States)

    Mohajerani, Hadis; Casper, Markus; Kholghi, Majid; Mosaedi, Abolfazl; Farmani, Raziyeh; Saadoddin, Amir; Meftah Halaghi, Mehdi

    2017-04-01

    This paper presents management of groundwater resource using a Bayesian Decision Network (BDN). The Kordkooy region in North East of Iran has been selected as study area. The region has been divided to three parts based on Transmissivity (T) and Electrical Conductivity (EC) values. The BDN parameters (prior probabilities and Conditional Probability Tables (CPTs) have been identified for each of the three zones. Three groups of management scenarios have been developed based on the two decision variables including "Crop pattern" and "Domestic water demand" across the three zones of the study area: 1) status quo management for all three zones representing current conditions. 2) the effect of change in cropping pattern on management endpoints and 3) the effect of increasing domestic water demand on management endpoints in the future. The outcomes arising from implementing each scenario have been predicted using the BDN for each of the zones. Results reveal that probability of drawdown in groundwater levels of southern areas is relatively high compared with other zones. Groundwater withdrawal from northern and northwestern areas of the study area should be limited due to the groundwater quality problems associated with shallow groundwater of these two zones. The ability of the Bayesian Decision Network to take into account key uncertainties in natural resources and performing a meaningful analysis in cases where there is not vast amount of information and observed data available -even based partly on expert opinion- emphasizes the advantage of this approach in groundwater resources management process, as limited data availability was a serious problem faced by groundwater resources of the study area.

  19. Evaluation of plant biomass resources available for replacement of fossil oil.

    Science.gov (United States)

    Henry, Robert J

    2010-04-01

    The potential of plants to replace fossil oil was evaluated by considering the scale of production required, the area of land needed and the types of plants available. High yielding crops (50 tonnes/ha) that have a high conversion efficiency (75%) would require a global land footprint of around 100 million ha to replace current (2008) oil consumption. Lower yielding or less convertible plants would require a larger land footprint. Domestication of new species as dedicated energy crops may be necessary. A systematic analysis of higher plants and their current and potential uses is presented. Plant biotechnology provides tools to improve the prospects of replacing oil with plant-derived biomass by increasing the amount of biomass produced per unit area of land and improving the composition of the biomass to increase the efficiency of conversion to biofuel and biomaterials. Options for the production of high value coproducts and the expression of processing aids such as enzymes in the plant may add further value to plants as bioenergy resources.

  20. Moving towards a reliable HIV incidence test - current status, resources available, future directions and challenges ahead.

    Science.gov (United States)

    Murphy, G; Pilcher, C D; Keating, S M; Kassanjee, R; Facente, S N; Welte, A; Grebe, E; Marson, K; Busch, M P; Dailey, P; Parkin, N; Osborn, J; Ongarello, S; Marsh, K; Garcia-Calleja, J M

    2017-04-01

    In 2011 the Incidence Assay Critical Path Working Group reviewed the current state of HIV incidence assays and helped to determine a critical path to the introduction of an HIV incidence assay. At that time the Consortium for Evaluation and Performance of HIV Incidence Assays (CEPHIA) was formed to spur progress and raise standards among assay developers, scientists and laboratories involved in HIV incidence measurement and to structure and conduct a direct independent comparative evaluation of the performance of 10 existing HIV incidence assays, to be considered singly and in combinations as recent infection test algorithms. In this paper we report on a new framework for HIV incidence assay evaluation that has emerged from this effort over the past 5 years, which includes a preliminary target product profile for an incidence assay, a consensus around key performance metrics along with analytical tools and deployment of a standardized approach for incidence assay evaluation. The specimen panels for this evaluation have been collected in large volumes, characterized using a novel approach for infection dating rules and assembled into panels designed to assess the impact of important sources of measurement error with incidence assays such as viral subtype, elite host control of viraemia and antiretroviral treatment. We present the specific rationale for several of these innovations, and discuss important resources for assay developers and researchers that have recently become available. Finally, we summarize the key remaining steps on the path to development and implementation of reliable assays for monitoring HIV incidence at a population level.

  1. In silico identification of transcription factors in Medicago sativa using available transcriptomic resources.

    Science.gov (United States)

    Postnikova, Olga A; Shao, Jonathan; Nemchinov, Lev G

    2014-06-01

    Transcription factors (TFs) are proteins that govern organismal development and response to the environment by regulating gene expression. Information on the amount and diversity of TFs within individual plant species is critical for understanding of their biological roles and evolutionary history across the plant kingdom. Currently, only scattered information on separate TFs is available for alfalfa, the most extensively cultivated forage legume in the world. In the meantime, several large transcriptomic resources that can be used to identify and characterize alfalfa TF genes are freely accessible online. In this study, we have performed an in silico analysis of transcriptome data generated in our laboratory and publicly acquirable from other sources to reveal and systematize alfalfa transcription factors. Transcriptome-wide mining enabled prediction of 983 TFs along with their sequence features and putative phylogenies of the largest families. All data were assembled into a simple open-access database named AlfalfaTFDB ( http://plantpathology.ba.ars.usda.gov/alfalfatfdb.html ). Transcriptomic analysis used in this work represents an effective approach for the identification of TF genes in plants with incomplete genomes, such as alfalfa. Integrated TF repertoires of Medicago sativa will provide an important tool for studying regulation of gene expression in other complex non-model species of agricultural significance.

  2. 76 FR 55941 - Notice of Availability of the Draft Bakersfield Resource Management Plan and Draft Environmental...

    Science.gov (United States)

    2011-09-09

    ... development and other land use authorizations with resource values; and (6) climate change. The Draft RMP... resources in a multiple-use environment; (4) livestock grazing management to provide for economic benefit... livestock grazing from BLM managed lands in the planning area. Alternative E emphasizes the production of...

  3. Technical Information Resource on Rare Earth Elements Now Available to Public and Private Sector Stakeholders

    Science.gov (United States)

    A new EPA technical information resource, “Rare Earth Elements: A Review of Production, Processing, Recycling, and Associated Environmental Issues” has been produced as an introductory resource for those interested in learning more about REE mining and alternatives to meet demand...

  4. Managing raw materials scarcity : safeguarding the availability of geologically scarce mineral resources

    NARCIS (Netherlands)

    Henckens, M.L.C.M.

    2016-01-01

    Will the earth be able to keep on providing future generations of sufficient mineral resources, given the growing world population in combination with a growing GDP per world citizen? The research objectives were: To find out what geological scarcity means, which mineral resources are geologically

  5. Resource and power management in next generation networks

    OpenAIRE

    Limani Fazliu, Zana

    2017-01-01

    The limits of today's cellular communication systems are constantly being tested by the exponential increase in mobile data traffic, a trend which is poised to continue well into the next decade. Densification of cellular networks, by overlaying smaller cells, i.e., micro, pico and femtocells, over the traditional macrocell, is seen as an inevitable step in enabling future networks to support the expected increases in data rate demand. Next generation networks will most certainly be more hete...

  6. Resource Allocation and Cross Layer Control in Wireless Networks

    Science.gov (United States)

    2006-08-25

    Modiano , and J. Tsitsiklis, �Optimal energy allocation and admis- sion control for communication satellites,�IEEE Transactions on Networking, vol. 11...E. Modiano , �Improving delay in ad-hoc mobile networks via redundant packet transfers,�in Proceedings of Conference on Information Sciences and...M. J. Neely, E. Modiano , and C.-P. Li, �Fairness and optimal stochastic con- trol for heterogeneous networks,�in Proceedings of IEEE INFOCOM, Miami

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

    Directory of Open Access Journals (Sweden)

    Kyung-Geun Lee

    2013-06-01

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

  8. Evaluation of the ground-water resources of coastal Georgia; preliminary report on the data available as of July 1983

    Science.gov (United States)

    Krause, Richard E.; Matthews, Sharon E.; Gill, Harold E.

    1984-01-01

    A compilation of ground-water data that have been collected for nearly 100 years in the coastal area of Georgia as part of cooperative activities between the U.S. Geological Survey and other agencies is presented in this report. The compilation of pertinent data indicates that information is available for use in the evaluation of the ground-water resources of the 13 counties of coastal Georgia. Included in this report is a fairly complete discussion of previous and ongoing investigations and monitoring networks, and an extensive list of references. Maps at 1:24,000, 1:100,000; and 1:1000,000 scales contain well locations and identifers for all wells in the Ground Water Site Inventory (GWSI) data base of the National Water Data Storage and Retrieval System (WATSTORE). Tabular summaries of selected site information from GWSI, including well identifiers and names , latitude-longitude location, depth of well, altitude of land surface, and use of water are presented. Water-use data from the National Water Use Data System, and water use for irrigation from the University of Georgia, Department of Agriculture survey , are tabulated. Also included are pertinent information on geophysical surveys and data obtained, and proposed project activities, particularly test-monitor well drilling.

  9. Evaluation of available saline water resources in New Mexico for the production of microalgae

    Energy Technology Data Exchange (ETDEWEB)

    Lansford, R.; Hernandez, J.; Enis, P.; Truby, D.; Mapel, C.

    1990-08-01

    Researchers evaluated saline water resources in New Mexico for their suitability as sites for large-scale microalgae production facilities. Production of microalgae could provide a renewable source of fuel, chemicals, and food. In addition, making use of the unused saline water resources would increase the economic activity in the state. After analyzing the 15 billion acre-ft of unused saline water resources in the state, scientists narrowed the locations down to six sites with the most potential. With further analysis, they chose the Tularosa Basin in southern New Mexico as the best-suited area for 100-hectare microalgae production facility. 34 refs., 38 figs., 14 tabs.

  10. 76 FR 56215 - John H. Chafee Coastal Barrier Resources System; Baldwin and Mobile Counties, AL; Availability of...

    Science.gov (United States)

    2011-09-12

    ... Fish and Wildlife Service John H. Chafee Coastal Barrier Resources System; Baldwin and Mobile Counties... (Service), announce the availability of a John H. Chafee Coastal Barrier Resources System (CBRS) draft... aquatic habitat. These areas are depicted on a series of maps entitled ``John H. Chafee Coastal Barrier...

  11. 78 FR 19294 - Notice of Availability of the Clear Creek Management Area Proposed Resource Management Plan and...

    Science.gov (United States)

    2013-03-29

    ... Bureau of Land Management Notice of Availability of the Clear Creek Management Area Proposed Resource Management Plan and Final Environmental Impact Statement, California AGENCY: Bureau of Land Management... of Land Management (BLM) has prepared a Proposed Resource Management Plan (RMP)/Final Environmental...

  12. 77 FR 31036 - Notice of Availability of the Record of Decision for the Taos Resource Management Plan...

    Science.gov (United States)

    2012-05-24

    ...] [FR Doc No: 2012-12680] DEPARTMENT OF THE INTERIOR Bureau of Land Management [LLNMF02000 L16100000.DT0000 LXSS026G0000] Notice of Availability of the Record of Decision for the Taos Resource Management... (ROD)/Approved Resource Management Plan (RMP) for the Taos Field Office located in northern New Mexico...

  13. 77 FR 64349 - Notice of Availability of the Draft West Eugene Wetlands Resource Management Plan/Environmental...

    Science.gov (United States)

    2012-10-19

    ... Bureau of Land Management Notice of Availability of the Draft West Eugene Wetlands Resource Management Plan/Environmental Impact Statement, Oregon AGENCY: Bureau of Land Management, Interior. ACTION: Notice... (BLM) has prepared a Draft Resource Management Plan (RMP) and Draft Environmental Impact Statement (EIS...

  14. 78 FR 41947 - Notice of Availability of a Supplement to the Bighorn Basin Draft Resource Management Plan...

    Science.gov (United States)

    2013-07-12

    ... Bureau of Land Management Notice of Availability of a Supplement to the Bighorn Basin Draft Resource Management Plan/Environmental Impact Statement, Cody and Worland Field Offices, WY AGENCY: Bureau of Land... Resource Management Plan (RMP) and Environmental Impact Statement (EIS) ] for the Bighorn Basin Planning...

  15. Community knowledge of law at the end of life: availability and accessibility of web-based resources.

    Science.gov (United States)

    White, Ben; Willmott, Lindy; Tilse, Cheryl; Wilson, Jill; Lawson, Deborah; Pearce, Angela; Dunn, Jeffrey; Aitken, Joanne F; Feeney, Rachel; Jowett, Stephanie

    2017-03-30

    Objective The aim of the present study was to identify online resources community members may access to inform themselves about their legal duties and rights in end-of-life decision making.Methods Resource mapping identified online resources that members of the public in New South Wales, Victoria and Queensland are likely to identify, and assessed the ease or difficulty in locating them. Resources were then critically analysed for accessibility of language and format using the Patient Education Materials Assessment Tool (PEMAT).Results Identified resources differed considerably based on whether search terms identified by community members or experts were used. Most resources focused on advance directives, enduring powers of attorney and substitute decision making. Relatively few provided information about legal duties (e.g. powers and responsibilities of substitute decision makers) or resolving conflict with health practitioners. Accessibility (understandability and actionability) of resource content varied.Conclusions Although numerous resources on end-of-life law are available online, community members may not be able to identify relevant resources or find resource content accessible.What is known about the topic? Research on participation by patients in decision making about their treatment has focused primarily on medical rather than legal knowledge.What does this paper add? The present study investigated which online resources community members may access to inform themselves about the law on end-of-life decision making. The resources identified were analysed for ease of location and content accessibility.What are the implications for practitioners? Authors of online resources on end-of-life decision making should consider whether their resources can be: (1) identified by search terms used by the public; (2) understood by a general audience; and (3) readily used to promote reader action.

  16. General-purpose computer networks and resource sharing in ERDA. Volume 3. Remote resource-sharing experience and findings

    Energy Technology Data Exchange (ETDEWEB)

    1977-07-15

    The investigation focused on heterogeneous networks in which a variety of dissimilar computers and operating systems were interconnected nationwide. Homogeneous networks, such as MFE net and SACNET, were not considered since they could not be used for general purpose resource sharing. Issues of privacy and security are of concern in any network activity. However, consideration of privacy and security of sensitive data arise to a much lesser degree in unclassified scientific research than in areas involving personal or proprietary information. Therefore, the existing mechanisms at individual sites for protecting sensitive data were relied on, and no new protection mechanisms to prevent infringement of privacy and security were attempted. Further development of ERDA networking will need to incorporate additional mechanisms to prevent infringement of privacy. The investigation itself furnishes an excellent example of computational resource sharing through a heterogeneous network. More than twenty persons, representing seven ERDA computing sites, made extensive use of both ERDA and non-ERDA computers in coordinating, compiling, and formatting the data which constitute the bulk of this report. Volume 3 analyzes the benefits and barriers encountered in actual resource sharing experience, and provides case histories of typical applications.

  17. Patient-Centered Network of Learning Health Systems: Developing a resource for clinical translational research.

    Science.gov (United States)

    Finney Rutten, L J; Alexander, A; Embi, P J; Flores, G; Friedman, C; Haller, I V; Haug, P; Jensen, D; Khosla, S; Runger, G; Shah, N D; Winden, T; Roger, V L

    2017-02-01

    The Learning Health System Network clinical data research network includes academic medical centers, health-care systems, public health departments, and health plans, and is designed to facilitate outcomes research, pragmatic trials, comparative effectiveness research, and evaluation of population health interventions. The Learning Health System Network is 1 of 13 clinical data research networks assembled to create, in partnership with 20 patient-powered research networks, a National Patient-Centered Clinical Research Network. Herein, we describe the Learning Health System Network as an emerging resource for translational research, providing details on the governance and organizational structure of the network, the key milestones of the current funding period, and challenges and opportunities for collaborative science leveraging the network.

  18. 76 FR 57759 - Notice of Availability of Draft Resource Management Plan and Draft Environmental Impact Statement...

    Science.gov (United States)

    2011-09-16

    ... advance through public notices, media releases and/or mailings. ADDRESSES: You may submit comments related... landscape. Alternative C emphasizes resource protection and sustaining the ecological integrity of habitats... Area, Kremmling Cretaceous Ammonite Research Natural Area, Kremmling Potential Conservation Area...

  19. 76 FR 44039 - Notice of Availability of the Draft Resource Management Plan Amendment, Draft Environmental...

    Science.gov (United States)

    2011-07-22

    ... Development--The planning amendment addresses energy resource decision (i.e., oil and gas, coal, solar, wind... Management--VRM class designations may influence maintenance or sustainability of special status species...

  20. First Brazilian Real Time Network DGPS through the Internet: Development, Application and Availability Analyses

    Science.gov (United States)

    Alves, D.; Dalbelo, L.; Monico, J.; Shimabukuro, M.

    2012-01-01

    The Global Positioning System (GPS) is widely used by the civil community. Differential GPS (DGPS) was developed to provide better accuracy than autonomous GPS. The DGPS concept is based on the high correlation of errors due to atmospheric effects, satellite clocks and orbits. However, as the baseline grows, its efficiency decreases because the error correlation is reduced. This limitation can be handled by using a reference station network and applying the network DGPS concept (called NDGPS). In this paper, the goal is to present aspects related to the development and application of NDGPS in real time at the São Paulo state network in Brazil. The NDGPS corrections were computed from data received via the Internet using NTRIP (Networked Transport of RTCM via Internet Protocol). Our implementation was based on BNC (BKG Ntrip Client) software. NDGPS provided RMS improvements of up to 59% in horizontal components and 31% in vertical components when compared to DGPS. The availability of the system, the first of this nature in Brazil, was also analyzed within the context of the SP State GNSS Network, located in the southeastern region of Brazil. The results also serve as an indication of the quality of local internet infrastructure for using in geodetic positioning.

  1. Network analysis: a new tool for resource managers

    Science.gov (United States)

    Ruth H. Allen

    1980-01-01

    Resource managers manipulate ecosystems for direct or indirect human uses. Examples of relatively well studied resource management issues include familiar biological products such as: forests, ranges, fish and wildlife; or physical products such as air, water and soil. Until very recently, urban environments received much less scholarly attention. However, as Spurr (...

  2. “The Bush is No More”: Insights on Institutional Change and Natural Resource Availability in Rural South Africa

    Science.gov (United States)

    Kirkland, Tracy; Hunter, Lori M.; Twine, Wayne

    2011-01-01

    The past decade has brought substantial transition to South Africa. The introduction of democracy in 1994 has yielded important political and socioeconomic transformations affecting millions of people. Here, we explore the impact of institutional and structural changes on the availability and management of fuelwood, a key natural resource in rural South Africa. As in other developing regions, many households depend on natural resources for both sustenance and energy needs. Drawing on qualitative data from 32 interviews, our objective is to describe, from the perspective of the respondents, (1) resource scarcity, (2) the underlying causes of resource scarcity, (3) the role of traditional authority in managing resources, and (4) strategies used by community members in the face of resource scarcity. The results have important implications for the well-being of both social and natural systems in many transitional, rural developing societies. PMID:21909188

  3. Automated Negotiation for Resource Assignment in Wireless Surveillance Sensor Networks

    Science.gov (United States)

    de la Hoz, Enrique; Gimenez-Guzman, Jose Manuel; Marsa-Maestre, Ivan; Orden, David

    2015-01-01

    Due to the low cost of CMOS IP-based cameras, wireless surveillance sensor networks have emerged as a new application of sensor networks able to monitor public or private areas or even country borders. Since these networks are bandwidth intensive and the radioelectric spectrum is limited, especially in unlicensed bands, it is mandatory to assign frequency channels in a smart manner. In this work, we propose the application of automated negotiation techniques for frequency assignment. Results show that these techniques are very suitable for the problem, being able to obtain the best solutions among the techniques with which we have compared them. PMID:26610512

  4. Resource partitioning in freshwater turtle communities: A null model meta-analysis of available data

    Science.gov (United States)

    Luiselli, Luca

    2008-07-01

    Resource partitioning is one of the most intensely studied issues in ecology since the mid-1900s, nonetheless this issue has never been examined in detail for several important animal groups, including the freshwater turtles. In this paper I re-analyze by null models several studies on resource partitioning by freshwater turtles published in the peer-reviewed literature. These studies originated from all continents and from a variety of climatic and habitat conditions. I used data given in the original papers to recalculate dietary overlap between species. Then, the true datasets were compared to randomly generated datasets produced by 3 × 10 4 Monte Carlo permutations, by using two different randomization algorithms (RA2 and RA3 of Lawlor, 1980). Datasets were inspected to find non-random structure of the various communities along four resource dimensions: macro-habitat, micro-habitat, food, and time. Based on my meta-analysis, I concluded that the micro-habitat resource is the most important dimension (it was the resource partitioned in nearly 80% of the study cases), followed by the food resource dimension (nearly 70%), whereas macro-habitat and time were clearly less important. In relation to micro-habitat dimension, the selection of basking site typology is perhaps the main aspect of the microhabitat niche to be partitioned. Logistic regression models indicated that the presence of a resource partitioning structure in the dataset was influenced only by matrix size, and not by number of species, continent, presence of substantial body size differences among coexisting species, or tropical versus non-tropical origin. A combination of causes may explain the observed patterns: interspecific competition is likely important in shaping several turtle communities, but intrinsic and extrinsic constraints and predation are also relevant.

  5. A note on some properties of an efficient network resource allocation mechanism

    Directory of Open Access Journals (Sweden)

    Fernando Beltrán

    2004-11-01

    Full Text Available Presentamos algunas propiedades límite de un mecanismo de asignación de recursos en redes conocido como la Subasta Progresiva de Segundo Precio (PSP. Este mecanismo busca asignar eficientemente recursos de red tales como ancho de banda y capacidad de buffer, en un ambiente caracterizado por usuarios que compiten; la subasta PSP busca resolver, o al menos aliviar, la congestión en una red exigiendo un intercambio de información entre el subastador y los usuarios sin mucha carga de señalización, y resolviendo el problema de la asignación de un recurso (teóricamente infinitamente divisible. La regla de asignación está inspirada en la subasta de segundo precio (Vickrey. Nuestro análisis de la subasta PSP explora sus propiedades límite, por ejemplo, cómo cambia la asignación en la presencia de un conjunto polarizado de usuarios. Esto último se refiere a una situación en la que los usuarios se dividen en dos grupos: unos con alta demanda y baja valoración por el recurso y otros con baja demanda y alta valoración. Mecanismos tales como las subastas se han vuelto muy populares para la asignación de recursos en redes que presentan congestión, tales como el acceso a servicios Internet. / We present some limiting properties of a network resource allocation mechanism known as the Progressive Second Price (PSP auction. This mechanism aims at efficiently allocate network resources, such as bandwidth or buffer capacity, in an environment characterized by competing users; the PSP auction seeks to solve or at least to ameliorate congestion in a network demanding a low signalling burden between the auctioneer and the users, and solving the allocation problem of an (theoretically infinitely divisible resource. The allocation rule is inspired in the second price (Vickrey auction. Our analysis of the PSP auction explores its limiting properties, namely, how the allocation changes in the presence of a polarized set of users. A polarized set of

  6. Control Policies Approaching HGI Performance in Heavy Traffic for Resource Sharing Networks

    OpenAIRE

    Budhiraja, Amarjit; Johnson, Dane

    2017-01-01

    We consider resource sharing networks of the form introduced in the work of Massouli\\'{e} and Roberts(2000) as models for Internet flows. The goal is to study the open problem, formulated in Harrison et al. (2014), of constructing simple form rate allocation policies for broad families of resource sharing networks with associated costs converging to the Hierarchical Greedy Ideal performance in the heavy traffic limit. We consider two types of cost criteria, an infinite horizon discounted cost...

  7. Designing Resource-Bounded Reasoners using Bayesian Networks

    Data.gov (United States)

    National Aeronautics and Space Administration — In this work we are concerned with the conceptual design of large-scale diagnostic and health management systems that use Bayesian networks. While they are...

  8. Resource Allocation and Cross Layer Control in Wireless Networks

    National Research Council Canada - National Science Library

    Georgiadis, L; Neely, M; Tassiulas, L

    2006-01-01

    .... In this paper we will present abstract models that capture the cross layer interaction from the physical to transport layer in wireless network architectures including cellular, ad-hoc and sensor...

  9. Coordinated Radar Resource Management for Networked Phased Array Radars

    Science.gov (United States)

    2014-12-01

    computed, and the detection of a target is determined based on a Monte Carlo test. For each successful target confirmation, a measurement report is...detection based on Monte Carlo test • add appropriate random perturbations to detec- tion measurements Radar Targets Environment Input Parameters... Fuente and J.R. Casar-Corredera. Optimal radar pulse scheduling using a neural network. In IEEE Int. Conf. Neural Networks, volume 7, pages 4558–4591

  10. The role of strong-tie social networks in mediating food security of fish resources by a traditional riverine community in the Brazilian Amazon

    Directory of Open Access Journals (Sweden)

    Frédéric Mertens

    2015-09-01

    Full Text Available Social networks are a significant way through which rural communities that manage resources under common property regimes obtain food resources. Previous research on food security and social network analysis has mostly focused on egocentric network data or proxy variables for social networks to explain how social relations contribute to the different dimensions of food security. Whole-network approaches have the potential to contribute to former studies by revealing how individual social ties aggregate into complex structures that create opportunities or constraints to the sharing and distribution of food resources. We used a whole-network approach to investigate the role of network structure in contributing to the four dimensions of food security: food availability, access, utilization, and stability. For a case study of a riparian community from the Brazilian Amazon that is dependent on fish as a key element of food security, we mapped the community strong-tie network among 97% of the village population over 14 years old (n = 336 by integrating reciprocated friendship and occupational ties, as well as close kinship relationships. We explored how different structural properties of the community network contribute to the understanding of (1 the availability of fish as a community resource, (2 community access to fish as a dietary resource, (3 the utilization of fish for consumption in a way that allows the villagers to maximize nutrition while at the same time minimizing toxic risks associated with mercury exposure, and (4 the stability of the fish resources in local ecosystems as a result of cooperative behaviors and community-based management. The contribution of whole-network approaches to the study of the links between community-based natural resource management and food security were discussed in the context of recent social-ecological changes in the Amazonian region.

  11. Estimation of Distribution Algorithm for Resource Allocation in Green Cooperative Cognitive Radio Sensor Networks

    Directory of Open Access Journals (Sweden)

    Alagan Anpalagan

    2013-04-01

    Full Text Available Due to the rapid increase in the usage and demand of wireless sensor networks (WSN, the limited frequency spectrum available for WSN applications will be extremely crowded in the near future. More sensor devices also mean more recharging/replacement of batteries, which will cause significant impact on the global carbon footprint. In this paper, we propose a relay-assisted cognitive radio sensor network (CRSN that allocates communication resources in an environmentally friendly manner. We use shared band amplify and forward relaying for cooperative communication in the proposed CRSN. We present a multi-objective optimization architecture for resource allocation in a green cooperative cognitive radio sensor network (GC-CRSN. The proposed multi-objective framework jointly performs relay assignment and power allocation in GC-CRSN, while optimizing two conflicting objectives. The first objective is to maximize the total throughput, and the second objective is to minimize the total transmission power of CRSN. The proposed relay assignment and power allocation problem is a non-convex mixed-integer non-linear optimization problem (NC-MINLP, which is generally non-deterministic polynomial-time (NP-hard. We introduce a hybrid heuristic algorithm for this problem. The hybrid heuristic includes an estimation-of-distribution algorithm (EDA for performing power allocation and iterative greedy schemes for constraint satisfaction and relay assignment. We analyze the throughput and power consumption tradeoff in GC-CRSN. A detailed analysis of the performance of the proposed algorithm is presented with the simulation results.

  12. Analyzing the Impact of Storage Shortage on Data Availability in Decentralized Online Social Networks

    Directory of Open Access Journals (Sweden)

    Songling Fu

    2014-01-01

    Full Text Available Maintaining data availability is one of the biggest challenges in decentralized online social networks (DOSNs. The existing work often assumes that the friends of a user can always contribute to the sufficient storage capacity to store all data. However, this assumption is not always true in today’s online social networks (OSNs due to the fact that nowadays the users often use the smart mobile devices to access the OSNs. The limitation of the storage capacity in mobile devices may jeopardize the data availability. Therefore, it is desired to know the relation between the storage capacity contributed by the OSN users and the level of data availability that the OSNs can achieve. This paper addresses this issue. In this paper, the data availability model over storage capacity is established. Further, a novel method is proposed to predict the data availability on the fly. Extensive simulation experiments have been conducted to evaluate the effectiveness of the data availability model and the on-the-fly prediction.

  13. Optimising The Available Scarce Water Resources At European Scale In A Modelling Environment: Results And Challenges

    Science.gov (United States)

    de Roo, Ad; Burek, Peter; Gentile, Alessandro; Udias, Angel; Bouraoui, Faycal

    2013-04-01

    As a next step to European drought monitoring and forecasting, which is covered in the European Drought Observatory (EDO) activity of JRC, a modeling environment has been developed to assess optimum measures to match water availability and water demand, while keeping ecological, water quality and flood risk aspects also into account. A multi-modelling environment has been developed to assess combinations of water retention measures, water savings measures, and nutrient reduction measures for continental Europe. These simulations have been carried out to assess the effects of those measures on several hydro-chemical indicators, such as the Water Exploitation Index, Environmental Flow indicators, low-flow frequency, N and P concentrations in rivers, the 50-year return period river discharge as an indicator for flooding, and economic losses due to water scarcity for the agricultural sector, the industrial sector, and the public sector. Also, potential flood damage of a 100-year return period flood has been used as an indicator. This modeling environment consists of linking the agricultural CAPRI model, the land use LUMP model, the water quantity LISFLOOD model, the water quality EPIC model, the combined water quantity/quality and hydro-economic LISQUAL model and a multi-criteria optimization routine. A python interface platform (IMO) has been built to link the different models. The work was carried out in the framework of a new European Commission policy document "Blueprint to Safeguard Europe's Water Resources", COM(2012)673), launched in November 2012. Simulations have been carried out to assess the effects of water retention measures, water savings measures, and nutrient reduction measures on several hydro-chemical indicators, such as the Water Exploitation Index, Environmental Flow indicators, N and P concentrations in rivers, the 50-year return period river discharge as an indicator for flooding, and economic losses due to water scarcity for the agricultural

  14. Modelling distributed energy resources in energy service networks

    CERN Document Server

    Acha, Salvador

    2013-01-01

    Focuses on modelling two key infrastructures (natural gas and electrical) in urban energy systems with embedded technologies (cogeneration and electric vehicles) to optimise the operation of natural gas and electrical infrastructures under the presence of distributed energy resources

  15. A centralized feedback control model for resource management in wireless networks

    NARCIS (Netherlands)

    Yang, Y.; Haverkort, Boudewijn R.H.M.; Heijenk, Geert; Cloth, L.; Hiltunen, M.; van Moorsel, A.

    2007-01-01

    In a wireless environment, guaranteeing QoS constraints is challenging because applications at multiple devices share the same limited radio bandwidth in the network. In this paper we introduce and study a resource management model for centralized wireless networks, using feedback control theory.

  16. Self-Adaptive Prediction of Cloud Resource Demands Using Ensemble Model and Subtractive-Fuzzy Clustering Based Fuzzy Neural Network

    Directory of Open Access Journals (Sweden)

    Zhijia Chen

    2015-01-01

    Full Text Available In IaaS (infrastructure as a service cloud environment, users are provisioned with virtual machines (VMs. To allocate resources for users dynamically and effectively, accurate resource demands predicting is essential. For this purpose, this paper proposes a self-adaptive prediction method using ensemble model and subtractive-fuzzy clustering based fuzzy neural network (ESFCFNN. We analyze the characters of user preferences and demands. Then the architecture of the prediction model is constructed. We adopt some base predictors to compose the ensemble model. Then the structure and learning algorithm of fuzzy neural network is researched. To obtain the number of fuzzy rules and the initial value of the premise and consequent parameters, this paper proposes the fuzzy c-means combined with subtractive clustering algorithm, that is, the subtractive-fuzzy clustering. Finally, we adopt different criteria to evaluate the proposed method. The experiment results show that the method is accurate and effective in predicting the resource demands.

  17. On Tradeoffs between Trust Accuracy and Resource Consumption in Communications and Social Networks

    Science.gov (United States)

    2016-04-11

    sociological effects is a very complex problem. Elements of trust relationship dynamics in the communication network context can be adapted to...On Tradeoffs between Trust Accuracy and Resource Consumption in Communications and Social Networks Jin-Hee Cho, Kevin Chan, Ananthram Swami, Brian...effectively is critical in tactical networks in order to facilitate cooperation and decision making tasks as well as to meet system goals such as

  18. Design considerations for medium access control in resource constrained embedded wireless networks

    OpenAIRE

    Ansari, Junaid

    2012-01-01

    Recent years have experienced a huge influx of daily life applications based on embedded wireless networks. While new applications with more demanding requirements and challenging deployment conditions are being explored, most of the existing networks suffer from communication deficiencies, inefficient use of resources, and inability to satisfy desired quality of service requirements. In order to carry on exploitation and exploration of embedded wireless networks in different daily life appli...

  19. Applications of Economic and Pricing Models for Resource Management in 5G Wireless Networks: A Survey

    OpenAIRE

    Luong, Nguyen Cong; Wang, Ping; Niyato, Dusit; Liang, Ying-Chang; Hou, Fen; Han, Zhu

    2017-01-01

    This paper presents a comprehensive literature review on applications of economic and pricing theory for resource management in the evolving fifth generation (5G) wireless networks. The 5G wireless networks are envisioned to overcome existing limitations of cellular networks in terms of data rate, capacity, latency, energy efficiency, spectrum efficiency, coverage, reliability, and cost per information transfer. To achieve the goals, the 5G systems will adopt emerging technologies such as mas...

  20. 78 FR 19291 - Notice of Availability of the Draft Billings and Pompeys Pillar National Monument Resource...

    Science.gov (United States)

    2013-03-29

    ... conservation of natural and cultural resources while providing for compatible development and use; Alternative... riding, closed to use of fireworks, closed to hang gliding, closed to paint ball activities, closed to... additional 576 acres were acquired from The Conservation Fund by the BLM in 2009 using money received from...

  1. Possible climate change impacts on water resources availability in a large semiarid catchment in Northeast Brazil

    NARCIS (Netherlands)

    Bronstert, Axel; Güntner, Andreas; de Araújo, José Carlos; Jaeger, Annekathrin; Krol, Martinus S.; Wagener, T.; Franks, S.; Gupta, H.V.; Bogh, E.; Bastidas, L.; Nobre, C.; de Oliveira Galvao, C.

    2005-01-01

    The semiarid region of Northeast Brazil is characterized by water scarcity, vulnerability of natural resources, and pronounced climatic variability. An integrated model has been developed to simulate this complex situation with an emphasis on a large-scale representation of hydrological processes

  2. Introducing the LHC in the Classroom: An Overview of Education Resources Available

    Science.gov (United States)

    Wiener, Gerfried J.; Woithe, Julia; Brown, Alexander; Jende, Konrad

    2016-01-01

    In the context of the recent re-start of CERN's Large Hadron Collider (LHC) and the challenge presented by unidentified falling objects (UFOs), we seek to facilitate the introduction of high energy physics in the classroom. Therefore, this paper provides an overview of the LHC and its operation, highlighting existing education resources, and…

  3. 77 FR 41444 - Notice of Availability of the Draft Resource Management Plan and Draft Environmental Impact...

    Science.gov (United States)

    2012-07-13

    ... consequences of four alternative land- use plans under consideration for managing approximately 744,387 acres... characteristics, livestock grazing, transportation access, renewable energy, visual resources, wildland/urban... from locatable mineral entry. Torreon Fossil Fauna ACEC (Currently 6,488 acres is designated as a SMA...

  4. Energy aware planning of multiple virtual infrastructures over converged optical network and IT physical resources.

    Science.gov (United States)

    Anastasopoulos, Markos P; Tzanakaki, Anna; Georgakilas, Konstantinos; Simeonidou, Dimitra

    2011-12-12

    This paper studies energy efficient planning of multiple concurrent virtual infrastructures over a converged physical infrastructure incorporating integrated optical network and IT resources. An MILP model for virtualization of the underlying physical resources is proposed and validated achieving significant energy savings. © 2011 Optical Society of America

  5. Analyzing the impact of storage shortage on data availability in decentralized online social networks.

    Science.gov (United States)

    Fu, Songling; He, Ligang; Liao, Xiangke; Li, Kenli; Huang, Chenlin

    2014-01-01

    Maintaining data availability is one of the biggest challenges in decentralized online social networks (DOSNs). The existing work often assumes that the friends of a user can always contribute to the sufficient storage capacity to store all data. However, this assumption is not always true in today's online social networks (OSNs) due to the fact that nowadays the users often use the smart mobile devices to access the OSNs. The limitation of the storage capacity in mobile devices may jeopardize the data availability. Therefore, it is desired to know the relation between the storage capacity contributed by the OSN users and the level of data availability that the OSNs can achieve. This paper addresses this issue. In this paper, the data availability model over storage capacity is established. Further, a novel method is proposed to predict the data availability on the fly. Extensive simulation experiments have been conducted to evaluate the effectiveness of the data availability model and the on-the-fly prediction.

  6. Novel Machine Learning-Based Techniques for Efficient Resource Allocation in Next Generation Wireless Networks

    KAUST Repository

    AlQuerm, Ismail A.

    2018-02-21

    There is a large demand for applications of high data rates in wireless networks. These networks are becoming more complex and challenging to manage due to the heterogeneity of users and applications specifically in sophisticated networks such as the upcoming 5G. Energy efficiency in the future 5G network is one of the essential problems that needs consideration due to the interference and heterogeneity of the network topology. Smart resource allocation, environmental adaptivity, user-awareness and energy efficiency are essential features in the future networks. It is important to support these features at different networks topologies with various applications. Cognitive radio has been found to be the paradigm that is able to satisfy the above requirements. It is a very interdisciplinary topic that incorporates flexible system architectures, machine learning, context awareness and cooperative networking. Mitola’s vision about cognitive radio intended to build context-sensitive smart radios that are able to adapt to the wireless environment conditions while maintaining quality of service support for different applications. Artificial intelligence techniques including heuristics algorithms and machine learning are the shining tools that are employed to serve the new vision of cognitive radio. In addition, these techniques show a potential to be utilized in an efficient resource allocation for the upcoming 5G networks’ structures such as heterogeneous multi-tier 5G networks and heterogeneous cloud radio access networks due to their capability to allocate resources according to real-time data analytics. In this thesis, we study cognitive radio from a system point of view focusing closely on architectures, artificial intelligence techniques that can enable intelligent radio resource allocation and efficient radio parameters reconfiguration. We propose a modular cognitive resource management architecture, which facilitates a development of flexible control for

  7. When we cannot speak: Eye contact disrupts resources available to cognitive control processes during verb generation.

    Science.gov (United States)

    Kajimura, Shogo; Nomura, Michio

    2016-12-01

    Although eye contact and verbal processing appear independent, people frequently avert their eyes from interlocutors during conversation. This suggests that there is interference between these processes. We hypothesized that such interference occurs because both processes share cognitive resources of a domain-general system and explored the influence of eye contact on simultaneous verb generation processes (i.e., retrieval and selection). In the present experiment, viewing a movie of faces with eyes directed toward the viewer delayed verbal generation more than a movie of faces with averted eyes; however, this effect was only present when both retrieval and selection demands were high. The results support the hypothesis that eye contact shares domain-general cognitive resource with verb generation. This further indicates that a full understanding of functional and dysfunctional communication must consider the interaction and interference of verbal and non-verbal channels. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. [Primary care resources available in digital libraries in Spanish Autonomous Regions].

    Science.gov (United States)

    Juan-Quilis, Verónica

    2013-03-01

    The Statement by the Spanish Society of Family and Community Medicine (SemFYC) on access to scientific information, highlights the need for providing digital libraries with certain resources in Autonomous Regions. The primary goal is to study the evidence-based medicine (EBM) coverage that SemFYC recommends regional virtual libraries. The regional health virtual libraries were identified and the access provided to health professionals, Internet presence, remote access and resources were studied. The results suggest there is ample coverage in 8 Autonomous Regions. At the top of the list was, Health Sciences Virtual Library of Navarre, the Balearic Islands Health Sciences Virtual Library, and Virtual Library of the Andalusian Public Health System. The present study needs to be extended to the other biomedical sciences, in order to obtain more accurate results. Copyright © 2012 Elsevier España, S.L. All rights reserved.

  9. Trauma-exposed firefighters: relationships among posttraumatic growth, posttraumatic stress, resource availability, coping and critical incident stress debriefing experience.

    Science.gov (United States)

    Sattler, David N; Boyd, Bill; Kirsch, Julie

    2014-12-01

    This project examines protective factors associated with resilience/posttraumatic growth and risk factors associated with posttraumatic stress among firefighters exposed to critical incidents. The participants were 286 (257 men and 29 women) volunteer and paid firefighters in Whatcom County, Washington. Participants completed an anonymous survey asking about demographics, critical incident exposure, posttraumatic stress symptoms, posttraumatic growth, resource availability, coping, occupational stress and critical incident stress debriefing experience. Most participants had significant critical incident exposure, and about half had attended critical incident stress debriefing sessions. Posttraumatic growth was associated with being female, critical incident exposure, critical incident stress debriefing attendance, posttraumatic stress symptoms (negative association), occupational support, occupation satisfaction, occupational effort, problem-focused coping, emotion-focused coping and personal characteristic resources. Posttraumatic stress symptoms were positively associated with years of firefighting, burnout, occupational effort and disengagement coping and negatively associated with critical incident stress debriefing attendance, posttraumatic growth, social support, internal locus of control, personal characteristic resources, energy resources and condition resources. The findings support conservation of resources stress theory and show that the maintenance and acquisition of resources can offset losses and facilitate resilience/posttraumatic growth. Implications of the findings for enhancing firefighter resources, facilitating resilience and minimizing occupational stressors are discussed. © 2014 John Wiley & Sons, Ltd.

  10. Introducing the LHC in the classroom: an overview of education resources available

    CERN Document Server

    Wiener, Gerfried J; Brown, Alexander; Jende, Konrad

    2016-01-01

    In the context of the recent re-start of CERN’s Large Hadron Collider (LHC) and the challenge presented by unidentified falling objects (UFOs), we seek to facilitate the introduction of high energy physics in the classroom. Therefore, this paper provides an overview of the LHC and its operation, highlighting existing education resources, and linking principal components of the LHC to topics in physics curricula.

  11. SAGES: a suite of freely-available software tools for electronic disease surveillance in resource-limited settings.

    Directory of Open Access Journals (Sweden)

    Sheri L Lewis

    Full Text Available Public health surveillance is undergoing a revolution driven by advances in the field of information technology. Many countries have experienced vast improvements in the collection, ingestion, analysis, visualization, and dissemination of public health data. Resource-limited countries have lagged behind due to challenges in information technology infrastructure, public health resources, and the costs of proprietary software. The Suite for Automated Global Electronic bioSurveillance (SAGES is a collection of modular, flexible, freely-available software tools for electronic disease surveillance in resource-limited settings. One or more SAGES tools may be used in concert with existing surveillance applications or the SAGES tools may be used en masse for an end-to-end biosurveillance capability. This flexibility allows for the development of an inexpensive, customized, and sustainable disease surveillance system. The ability to rapidly assess anomalous disease activity may lead to more efficient use of limited resources and better compliance with World Health Organization International Health Regulations.

  12. Multimode dynamics in a network with resource mediated coupling

    DEFF Research Database (Denmark)

    Postnov, D.E.; Sosnovtseva, Olga; Scherbakov, P.

    2008-01-01

    The purpose of this paper is to study the special forms of multimode dynamics that one can observe in systems with resource- mediated coupling, i. e., systems of self- sustained oscillators in which the coupling takes place via the distribution of primary resources that controls the oscillatory...... connected to a common power supply. The two- oscillator system displays antiphase synchronization, and it is interesting to note that two- mode oscillations continue to exist outside of the parameter range in which oscillations occur for the individual unit. At low coupling strengths, the multioscillator...

  13. A Practical Resource Management Scheme for Cellular Underlaid D2D Networks

    Directory of Open Access Journals (Sweden)

    Tae-Won Ban

    2017-10-01

    Full Text Available In this paper, we investigate a resource management scheme for cellular underlaid device-to-device (D2D communications, which are an integral part of mobile caching networks. D2D communications are allowed to share radio resources with cellular communications as long as the generating interference of D2D communications satisfies an interference constraint to secure cellular communications. Contrary to most of the other studies, we propose a distributed resource management scheme for cellular underlaid D2D communications focusing on a practical feasibility. In the proposed scheme, the feedback of channel information is not required because all D2D transmitters use a fixed transmit power and every D2D transmitter determines when to transmit data on its own without centralized control. We analyze the average sum-rates to evaluate the proposed scheme and compare them with optimal values, which can be achieved when a central controller has the perfect entire channel information and the full control of all D2D communications. Our numerical results show that the average sum-rates of the proposed scheme approach the optimal values in low or high signal-to-noise power ratio (SNR regions. In particular, the proposed scheme achieves almost optimal average sum-rates in the entire SNR values in practical environments.

  14. Shorebird migration in the face of climate change: potential shifts in migration phenology and resource availability

    Science.gov (United States)

    Stutzman, Ryan J.; Fontaine, Joseph J

    2015-01-01

    Changes in temperature and seasonality resulting from climate change are heterogeneous, potentially altering important sources of natural selection acting on species phenology. Some species have apparently adapted to climate change but the ability of most species to adapt remains unknown. The life history strategies of migratory animals are dictated by seasonal factors, which makes these species particularly vulnerable to heterogeneous changes in climate and phenology. Here, we examine the phenology of migratory shorebirds, their habitats, and primary food resources, and we hypothesize how climate change may affect migrants through predicted changes in phenology. Daily abundance of shorebirds at stopover sites was correlated with local phenology and peaked immediately prior to peaks in invertebrate food resources. A close relationship between migrant and invertebrate phenology indicates that shorebirds may be vulnerable to changes in seasonality driven by climate change. It is possible that shifts in migrant and invertebrate phenology will be congruent in magnitude and direction, but because migration phenology is dependent on a suite of ecological factors, any response is likely to occur at a larger temporal scale and may lag behind the response of invertebrate food resources. The resulting lack of sufficient access to food at stopover habitats may cause migrants to extend migration and have cascading effects throughout their life cycle. If the heterogeneous nature of climate change results in uneven changes in phenology between migrants and their prey, it may threaten the long-term viability of migratory populations

  15. Social Network resources and self-rated health in a deprived Danish neighborhood

    DEFF Research Database (Denmark)

    Tanggaard Andersen, Pernille; Holst Algren, Maria; Fromsejer Heiberg, Regina

    2017-01-01

    by social network resources. This is the main aim of this article. Cross-sectional data from one deprived neighborhood located in Denmark were collected in 2008 and 2013 using a postal health survey. The target group was defined as adults older than 16 years. In 2008, 408 residents participated......Research has demonstrated that living in a deprived neighborhood contributes to the occurrence and development of poor health. Furthermore evidence shows that social networks are fundamental resources in preventing poor mental health. Neighborhood relationships and networks are vital for sustaining...... in the survey, and 405 residents participated in 2013. Our main explanatory variables were indicators of socioeconomic positions and social network resources. The analyses were conducted using univariate and bivariate analyses and multiple logistic regressions. The results showed that there was a significant...

  16. Policy Networks and Forest Resource Management in Ghana | Teye ...

    African Journals Online (AJOL)

    This paper employs a policy network model to explore the formal and informal interactions and structures which characterise forest management in Ghana. A comprehensive analysis of primary and secondary data reveals that forest management in Ghana has historically been influenced by complex relations of power and ...

  17. Network resource selection for data transfer processes in scientific workflows

    NARCIS (Netherlands)

    Zhao, Z.; Grosso, P.; Koning, R.; van der Ham, J.; de Laat, C.

    2010-01-01

    Quality of the service (QoS) plays an important role in the life-cycle of scientific workflows for composing and executing applications. However, the quality of network services has so far rarely been considered in composing and executing scientific workflows. Currently, scientific applications tune

  18. Integrated service resource reservation using queueing networks theory

    DEFF Research Database (Denmark)

    Brewka, Lukasz Jerzy; Iversen, Villy Bæk; Kardaras, Georgios

    2014-01-01

    This study analyses multi-server multi-service queueing networks with service protection. To guarantee each service a certain quality-of-service and at the same time ensure high utilisation of servers, a minimum capacity is reserved each service. In addition, all services share the remaining non...

  19. Temporal Dynamics and Resource Availability for Drosophilid Fruit Flies (Insecta, Diptera in a Gallery Forest in the Brazilian Savanna

    Directory of Open Access Journals (Sweden)

    Henrique Valadão

    2010-01-01

    Full Text Available Seasonality can cause severe bottlenecks in natural populations, even leading to local extinction. Large variation in resource availability may explain the bottlenecks, but the role of these variations is still poorly understood. The goal of this study was to analyze if temporal variations in the guild of drosophilids breeding in fruits of Mauritia flexuosa (Arecaceae can be explained by the shortage of this resource during the dry season. Fruits of M. flexuosa were collected over one year in a gallery forest located in the Central Brazilian Savanna. The drosophilid assemblage varied over time, with a lower density of species and of individuals in the dry season, when the percentage of colonized fruits was also smaller. These findings suggest that although the fruits were available during the dry season, they were underused. This way, the resource availability does not seem to regulate the community in the dry season.

  20. Effects of resource availability and propagule supply on native species recruitment in sagebrush ecosystems invaded by Bormus tectorum

    Science.gov (United States)

    Monica B. Mazzola; Jeanne C. Chambers; Robert R. Blank; David A. Pyke; Eugene W. Schupp; Kimberly G. Allcock; Paul S. Doescher; Robert S. Nowak

    2010-01-01

    Resource availability and propagule supply are major factors influencing establishment and persistence of both native and invasive species. Increased soil nitrogen (N) availability and high propagule inputs contribute to the ability of annual invasive grasses to dominate disturbed ecosystems. Nitrogen reduction through carbon (C) additions can potentially immobilize...

  1. Network-centric fuzzy resource manager: structure and validation

    Science.gov (United States)

    Smith, James F., III; Firth, Zachary

    2003-07-01

    A fuzzy logic expert system has been developed that automatically allocates electronic attack resources on different platforms in real-time. This resource manager is made up of four trees, the isolated platform tree, the multi-platform tree that allows an individual platform to respond to a threat. The multi-platform tree allows a group of platforms to respond to a threat in a collaborative fashion. A genetic algorithm is used to optimize the resource manager. A genetic program is used to evolve optimal fuzzy decision tree topology. The non-uniqueness of the tree structure is considered. The superiority of a genetic program evolved tree compared to a tree written down exclusively based on expertise is discussed. Fuzzy membership functions related to four fuzzy concepts are given. Experiments designed to test these concepts in the expert system are discussed, as well as the resource manager's ability to: allow multiple platforms to self-organize without the benefit of a commander; to tolerate errors made by other systems; and to deal with multiple distinct enemy strategies.

  2. Products and Services Available from the Southern California Earthquake Data Center (SCEDC) and the Southern California Seismic Network (SCSN)

    Science.gov (United States)

    Yu, E.; Bhaskaran, A.; Chen, S. L.; Andrews, J. R.; Thomas, V. I.; Hauksson, E.; Clayton, R. W.

    2016-12-01

    The Southern California Earthquake Data Center (SCEDC) archives continuous and triggered data from nearly 9429 data channels from 513 Southern California Seismic Network recorded stations. The SCEDC provides public access to these earthquake parametric and waveform data through web services, its website http://scedc.caltech.edu and through client application such as STP. This poster will describe the most recent significant developments at the SCEDC. The SCEDC now provides web services to access its holdings. Event Parametric Data (FDSN Compliant): http://service.scedc.caltech.edu/fdsnws/event/1/ Station Metadata (FDSN Compliant): http://service.scedc.caltech.edu/fdsnws/station/1/ Waveforms (FDSN Compliant): http://service.scedc.caltech.edu/fdsnws/dataselect/1/ Event Windowed Waveforms, phases: http://service.scedc.caltech.edu/webstp/ In an effort to assist researchers accessing catalogs from multiple seismic networks, the SCEDC has entered its earthquake parametric catalog into the ANSS Common Catalog (ComCat). Origin, phase, and magnitude information have been loaded. The SCEDC data holdings now include a double difference catalog (Hauksson et. al 2011) spanning 1981 through 2015 available via STP, and a focal mechanism catalog (Yang et al. 2011). As part of a NASA/AIST project in collaboration with JPL and SIO, the SCEDC now archives and distributes real time 1 Hz streams of GPS displacement solutions from the California Real Time Network. The SCEDC has implemented the Continuous Wave Buffer (CWB) to manage its waveform archive and allow users to access continuous data available within seconds of real time. This software was developed and currently in use at NEIC. SCEDC has moved its website (http://scedc.caltech.edu) to the Cloud. The Recent Earthquake Map and static web pages are now hosted by Amazon Web Services. This enables the web site to serve large number of users without competing for resources needed by SCSN/SCEDC mission critical operations.

  3. Routing and wavelength assignment based on normalized resource and constraints for all-optical network

    Science.gov (United States)

    Joo, Seong-Soon; Nam, Hyun-Soon; Lim, Chang-Kyu

    2003-08-01

    With the rapid growth of the Optical Internet, high capacity pipes is finally destined to support end-to-end IP on the WDM optical network. Newly launched 2D MEMS optical switching module in the market supports that expectations of upcoming a transparent optical cross-connect in the network have encouraged the field applicable research on establishing real all-optical transparent network. To open up a customer-driven bandwidth services, design of the optical transport network becomes more challenging task in terms of optimal network resource usage. This paper presents a practical approach to finding a route and wavelength assignment for wavelength routed all-optical network, which has λ-plane OXC switches and wavelength converters, and supports that optical paths are randomly set up and released by dynamic wavelength provisioning to create bandwidth between end users with timescales on the order of seconds or milliseconds. We suggest three constraints to make the RWA problem become more practical one on deployment for wavelength routed all-optical network in network view: limitation on maximum hop of a route within bearable optical network impairments, limitation on minimum hops to travel before converting a wavelength, and limitation on calculation time to find all routes for connections requested at once. We design the NRCD (Normalized Resource and Constraints for All-Optical Network RWA Design) algorithm for the Tera OXC: network resource for a route is calculated by the number of internal switching paths established in each OXC nodes on the route, and is normalized by ratio of number of paths established and number of paths equipped in a node. We show that it fits for the RWA algorithm of the wavelength routed all-optical network through real experiments on the distributed objects platform.

  4. An analysis and comparison of commonly available United Kingdom prescribing resources.

    Science.gov (United States)

    Cox, A R; Butt, T F; Ferner, R E

    2010-08-01

    Safe prescribing requires accurate and practical information about drugs. Our objective was to measure the utility of current sources of prescribing guidance when used to inform practical prescribing decisions, and to compare current sources of prescribing guidance in the UK with idealized prescribing guidance. We developed 25 clinical scenarios. Two independent assessors rated and ranked the performance of five common sources of prescribing guidance in the UK when used to answer the clinical scenarios. A third adjudicator facilitated review of any disparities. An idealized list of contents for prescribing guidance was developed and sent for comments to academics and users of prescribing guidance. Following consultation an operational check was used to assess compliance with the idealized criteria. The main outcome measures were relative utility in answering the clinical scenarios and compliance with the idealized prescribing guidance. Current sources of prescribing guidance used in the UK differ in their utility, when measured using clinical scenarios. The British National Formulary (BNF) and EMIS LV were the best performing sources in terms of both ranking [mean rank 1·24 and 2·20] and rating [%excellent or adequate 100% and 72%]. Current sources differed in the extent to which they fulfilled criteria for ideal prescribing guidance, but the BNF, and EMIS LV to a lesser extent, closely matched the criteria. We have demonstrated how clinical scenarios can be used to assess prescribing guidance resources. Producers of prescribing guidance documents should consider our idealized template. Prescribers require high-quality information to support their practice. Our test was helpful in distinguishing between prescribing resources. Producers of prescribing guidance should consider the utility of their products to end-users, particularly in those more complex areas where prescribers may need most support. Existing UK prescribing guidance resources differ in their

  5. Adaptive TrimTree: Green Data Center Networks through Resource Consolidation, Selective Connectedness and Energy Proportional Computing

    Directory of Open Access Journals (Sweden)

    Saima Zafar

    2016-10-01

    Full Text Available A data center is a facility with a group of networked servers used by an organization for storage, management and dissemination of its data. The increase in data center energy consumption over the past several years is staggering, therefore efforts are being initiated to achieve energy efficiency of various components of data centers. One of the main reasons data centers have high energy inefficiency is largely due to the fact that most organizations run their data centers at full capacity 24/7. This results into a number of servers and switches being underutilized or even unutilized, yet working and consuming electricity around the clock. In this paper, we present Adaptive TrimTree; a mechanism that employs a combination of resource consolidation, selective connectedness and energy proportional computing for optimizing energy consumption in a Data Center Network (DCN. Adaptive TrimTree adopts a simple traffic-and-topology-based heuristic to find a minimum power network subset called ‘active network subset’ that satisfies the existing network traffic conditions while switching off the residual unused network components. A ‘passive network subset’ is also identified for redundancy which consists of links and switches that can be required in future and this subset is toggled to sleep state. An energy proportional computing technique is applied to the active network subset for adapting link data rates to workload thus maximizing energy optimization. We have compared our proposed mechanism with fat-tree topology and ElasticTree; a scheme based on resource consolidation. Our simulation results show that our mechanism saves 50%–70% more energy as compared to fat-tree and 19.6% as compared to ElasticTree, with minimal impact on packet loss percentage and delay. Additionally, our mechanism copes better with traffic anomalies and surges due to passive network provision.

  6. OAFP starts practice-based resource/research network.

    Science.gov (United States)

    Mold, J W; Barton, E D

    1996-12-01

    The Oklahoma Academy of Family Physicians, in collaboration with the University of Oklahoma Health Sciences Center, has established a primary care practice-based research network with thirteen family practice offices currently participating. The practices are connected to each other and to the Health Sciences Center campuses in Oklahoma City and Tulsa by electronic mail and have begun their first research project involving the diagnosis and treatment of brown recluse spider bites in the primary care setting.

  7. Using Expectation Maximization and Resource Overlap Techniques to Classify Species According to Their Niche Similarities in Mutualistic Networks

    Directory of Open Access Journals (Sweden)

    Hugo Fort

    2015-11-01

    Full Text Available Mutualistic networks in nature are widespread and play a key role in generating the diversity of life on Earth. They constitute an interdisciplinary field where physicists, biologists and computer scientists work together. Plant-pollinator mutualisms in particular form complex networks of interdependence between often hundreds of species. Understanding the architecture of these networks is of paramount importance for assessing the robustness of the corresponding communities to global change and management strategies. Advances in this problem are currently limited mainly due to the lack of methodological tools to deal with the intrinsic complexity of mutualisms, as well as the scarcity and incompleteness of available empirical data. One way to uncover the structure underlying complex networks is to employ information theoretical statistical inference methods, such as the expectation maximization (EM algorithm. In particular, such an approach can be used to cluster the nodes of a network based on the similarity of their node neighborhoods. Here, we show how to connect network theory with the classical ecological niche theory for mutualistic plant-pollinator webs by using the EM algorithm. We apply EM to classify the nodes of an extensive collection of mutualistic plant-pollinator networks according to their connection similarity. We find that EM recovers largely the same clustering of the species as an alternative recently proposed method based on resource overlap, where one considers each party as a consuming resource for the other party (plants providing food to animals, while animals assist the reproduction of plants. Furthermore, using the EM algorithm, we can obtain a sequence of successfully-refined classifications that enables us to identify the fine-structure of the ecological network and understand better the niche distribution both for plants and animals. This is an example of how information theoretical methods help to systematize and

  8. Yoga Lessons for Consciousness Research: A Paralimbic Network Balancing Brain Resource Allocation

    Science.gov (United States)

    Lou, Hans C.; Joensson, Morten; Kringelbach, Morten L.

    2011-01-01

    Consciousness has been proposed to play a key role in shaping flexible learning and as such is thought to confer an evolutionary advantage. Attention and awareness are the perhaps most important underlying processes, yet their precise relationship is presently unclear. Both of these processes must, however, serve the evolutionary imperatives of survival and procreation. They are thus intimately bound by reward and emotion to help to prioritize efficient brain resource allocation in order to predict and optimize behavior. Here we show how this process is served by a paralimbic network consisting primarily of regions located on the midline of the human brain. Using many different techniques, experiments have demonstrated that this network is effective and specific for self-awareness and contributes to the sense of unity of consciousness by acting as a common neural path for a wide variety of conscious experiences. Interestingly, hemodynamic activity in the network decreases with focusing on external stimuli, which has led to the idea of a default mode network. This network is one of many networks that wax and vane as resources are allocated to accommodate the different cyclical needs of the organism primarily related to the fundamental pleasures afforded by evolution: food, sex, and conspecifics. Here we hypothesize, however, that the paralimbic network serves a crucial role in balancing and regulating brain resource allocation, and discuss how it can be thought of as a link between current theories of so-called “default mode,” “resting state networks,” and “global workspace.” We show how major developmental disorders of self-awareness and self-control can arise from problems in the paralimbic network as demonstrated here by the example of Asperger syndrome. We conclude that attention, awareness, and emotion are integrated by a paralimbic network that helps to efficiently allocate brain resources to optimize behavior and help survival. PMID:22203808

  9. Biomass Allocation of Stoloniferous and Rhizomatous Plant in Response to Resource Availability: A Phylogenetic Meta-Analysis

    Directory of Open Access Journals (Sweden)

    Xiu-Fang eXie

    2016-05-01

    Full Text Available Resource allocation to different functions is central in life-history theory. Plasticity of functional traits allows clonal plants to regulate their resource allocation to meet changing environments. In this study, biomass allocation traits of clonal plants were categorized into absolute biomass for vegetative growth versus for reproduction, and their relative ratios based on a data set including 115 species and derived from 139 published literatures. We examined general pattern of biomass allocation of clonal plants in response to availabilities of resource (e.g. light, nutrients and water using phylogenetic meta-analysis. We also tested whether the pattern differed among clonal organ types (stolon vs. rhizome. Overall, we found that stoloniferous plants were more sensitive to light intensity than rhizomatous plants, preferentially allocating biomass to vegetative growth, aboveground part and clonal reproduction under shaded conditions. Under nutrient- and water-poor condition, rhizomatous plants were constrained more by ontogeny than by resource availability, preferentially allocating biomass to belowground part. Biomass allocation between belowground and aboveground part of clonal plants generally supported the optimal allocation theory. No general pattern of trade-off was found between growth and reproduction, and neither between sexual and clonal reproduction. Using phylogenetic meta-analysis can avoid possible confounding effects of phylogeny on the results. Our results shown the optimal allocation theory explained a general trend, which the clonal plants are able to plastically regulate their biomass allocation, to cope with changing resource availability, at least in stoloniferous and rhizomatous plants.

  10. Availability, Use and Constraints to Use of Electronic Information Resources by Postgraduates Students at the University of Ibadan

    Directory of Open Access Journals (Sweden)

    Dare Samuel Adeleke

    2017-12-01

    Full Text Available Availability, awareness and use of electronic resources provide access to authoritative, reliable, accurate and timely access to information. The use of electronic information resources (EIRs can enable innovation in teaching and increase timeliness in research of postgraduate students which will eventual result into encouragement of the expected research-led enquiry in this digital age. The study adopted a descriptive survey design. Samples of 300 of postgraduate students within seven out 13 Faculties were randomly selected. Data were collected using questionnaire designed to elicit response from respondents and data were analyzed using descriptive statistics methods percentages, mean, and standard deviation. Results indicated that internet was ranked most available and used in the university. Low level of usage of electronic resources, in particular, full texts data bases is linked to a number of constraints: Interrupted power supply was ranked highest among other factors as speed and capacity of computers, retrieval of records with high recall and low precision, retrieving records relevant to information need, lack of knowledge of search techniques to retrieve information effectively, non possession of requisite IT skills and problems accessing the internet. The study recommended that usage of electronic resources be made compulsory, intensifying awareness campaigns concerning the availability, training on use of electronic resources and the problem of power outage be addressed.

  11. Modeling trophic resource availability for the first human settlers of Europe: the case of Atapuerca TD6.

    Science.gov (United States)

    Rodríguez-Gómez, Guillermo; Rodríguez, Jesús; Martín-González, Jesús Ángel; Goikoetxea, Idoia; Mateos, Ana

    2013-06-01

    Food resource availability strongly influences the survival opportunities of all organisms. The effect of animal food resource availability on the survival and dispersal of hominin populations is hotly debated. In this article, we present a mathematical model that provides estimations of the maximum and minimum available resources for secondary consumers in a palaeocommunity. This model provides insights into the intensity of competition and the available niche space for hominins in Europe during the early Galerian (1.2-0.8 Ma). Published data from the Atapuerca TD6 assemblage were used in combination with the model to investigate trophic dynamics and resource availability for a Homo antecessor population 800,000 years ago. The effect on our results of the possible presence at Atapuerca of some large carnivores not recorded in the fossil assemblage is also evaluated. Results indicate the existence of a rich ecosystem at Atapuerca at the end of the Early Pleistocene. Secondary production was abundant enough to maintain a hunter-gatherer population and a rich carnivore guild more diverse than that recorded in the TD6 assemblage. Based on these results, the practice of cannibalism by H. antecessor cannot be explained by a long-term scarcity of resources. High food availability at TD6 implies a low to moderate level of competition for resources between carnivores and humans. According to this interpretation, an empty niche for a highly carnivorous omnivore existed in Europe during the early Galerian, and it was successfully exploited by Homo. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. [Gastroenterology 2.0: useful resources for the gastroenterologist available on the Web 2.0].

    Science.gov (United States)

    Curioso, Walter H; Proaño, Alvaro; Ruiz, Eloy F

    2011-01-01

    The term Web 2.0 refers to the use of Internet applications which enable the users to share, participate and collaborate together on information. The objective of this study is to check different applications that use Web 2.0, which could help the gastroenterologist in his daily practice. The applications that will be checked include: blogs, microblogging, RSS, podcasts, wikis and social networks. "Gastroenterology 2.0" represents the applications, services, and tools based on Web 2.0, which are of easy use and easily accessible - to consumers, patients, gastroenterologists and other health professionals, as well as researchers. Although several studies have shown the benefits these technologies have on the medical practice, it is necessary to conduct further studies to demonstrate the use of these applications on improving health.

  13. SAGES: A Suite of Freely-Available Software Tools for Electronic Disease Surveillance in Resource-Limited Settings

    Science.gov (United States)

    Lewis, Sheri L.; Feighner, Brian H.; Loschen, Wayne A.; Wojcik, Richard A.; Skora, Joseph F.; Coberly, Jacqueline S.; Blazes, David L.

    2011-01-01

    Public health surveillance is undergoing a revolution driven by advances in the field of information technology. Many countries have experienced vast improvements in the collection, ingestion, analysis, visualization, and dissemination of public health data. Resource-limited countries have lagged behind due to challenges in information technology infrastructure, public health resources, and the costs of proprietary software. The Suite for Automated Global Electronic bioSurveillance (SAGES) is a collection of modular, flexible, freely-available software tools for electronic disease surveillance in resource-limited settings. One or more SAGES tools may be used in concert with existing surveillance applications or the SAGES tools may be used en masse for an end-to-end biosurveillance capability. This flexibility allows for the development of an inexpensive, customized, and sustainable disease surveillance system. The ability to rapidly assess anomalous disease activity may lead to more efficient use of limited resources and better compliance with World Health Organization International Health Regulations. PMID:21572957

  14. The Philadelphia Neurodevelopmental Cohort: A publicly available resource for the study of normal and abnormal brain development in youth.

    Science.gov (United States)

    Satterthwaite, Theodore D; Connolly, John J; Ruparel, Kosha; Calkins, Monica E; Jackson, Chad; Elliott, Mark A; Roalf, David R; Ryan Hopsona, Karthik Prabhakaran; Behr, Meckenzie; Qiu, Haijun; Mentch, Frank D; Chiavacci, Rosetta; Sleiman, Patrick M A; Gur, Ruben C; Hakonarson, Hakon; Gur, Raquel E

    2016-01-01

    The Philadelphia Neurodevelopmental Cohort (PNC) is a large-scale study of child development that combines neuroimaging, diverse clinical and cognitive phenotypes, and genomics. Data from this rich resource is now publicly available through the Database of Genotypes and Phenotypes (dbGaP). Here we focus on the data from the PNC that is available through dbGaP and describe how users can access this data, which is evolving to be a significant resource for the broader neuroscience community for studies of normal and abnormal neurodevelopment. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Combustion of available fossil fuel resources sufficient to eliminate the Antarctic Ice Sheet.

    Science.gov (United States)

    Winkelmann, Ricarda; Levermann, Anders; Ridgwell, Andy; Caldeira, Ken

    2015-09-01

    The Antarctic Ice Sheet stores water equivalent to 58 m in global sea-level rise. We show in simulations using the Parallel Ice Sheet Model that burning the currently attainable fossil fuel resources is sufficient to eliminate the ice sheet. With cumulative fossil fuel emissions of 10,000 gigatonnes of carbon (GtC), Antarctica is projected to become almost ice-free with an average contribution to sea-level rise exceeding 3 m per century during the first millennium. Consistent with recent observations and simulations, the West Antarctic Ice Sheet becomes unstable with 600 to 800 GtC of additional carbon emissions. Beyond this additional carbon release, the destabilization of ice basins in both West and East Antarctica results in a threshold increase in global sea level. Unabated carbon emissions thus threaten the Antarctic Ice Sheet in its entirety with associated sea-level rise that far exceeds that of all other possible sources.

  16. Available web-based teaching resources for health care professionals on screening for oral cancer

    Science.gov (United States)

    Varela-Centelles, Pablo; Insua, Angel; Warnakulasuriya, Saman; Rapidis, Alexander; Diz, Pedro; Seoane, Juan

    2015-01-01

    Objectives: To identify websites with adequate information on oral cancer screening for healthcare professionals (HCPs) and to assess both their quality and contents. Study Design: Websites were identified using Google and HON medical professional search engines using the terms “screening for oral cancer”. The first 100 sites retrieved by each engine were analysed using the DISCERN questionnaire (reliability), the V instrument (contents on oral cancer) and further by the Flesch-Kinkaid Reading Grade Level and the Flesch Reading Ease (readability). Results: The overall rating showed minimal shortcomings in the quality of the information in the websites. The coverage and correctness of information on “visual examination” was rated as fair/good, whereas updating of contents resulted very variable (eg: 81% for visual examination and 18.2% for molecular biomarkers). These results permitted to rank the websites housing relevant information for oral cancer. Top ranking websites were affiliated to the Oral Cancer Foundation (USA), WHO Collaborating Centre for oral cancer (UK) whose webpage is entitled “Oral Cancer Education and Research”, and the Clinical Guidelines maintained by the British Columbia Cancer Agency (Canada) and the British Dental Association (UK) respectively. Conclusions: There are web-based, HCP-addressed, resources on screening for oral cancer housing heterogeneous information both in quality and contents. The use of specific evaluation tools permits the selection of reliable websites on this topic with a potential to improve the existing educational gaps among HCPs. Key words:Oral cancer, early diagnosis, screening, secondary prevention, internet, teaching resources, continuous education. PMID:25475775

  17. Bioinformatics Training Network (BTN): a community resource for bioinformatics trainers

    DEFF Research Database (Denmark)

    Schneider, Maria V.; Walter, Peter; Blatter, Marie-Claude

    2012-01-01

    to the development of ‘high-throughput biology’, the need for training in the field of bioinformatics, in particular, is seeing a resurgence: it has been defined as a key priority by many Institutions and research programmes and is now an important component of many grant proposals. Nevertheless, when it comes...... and clearly tagged in relation to target audiences, learning objectives, etc. Ideally, they would also be peer reviewed, and easily and efficiently accessible for downloading. Here, we present the Bioinformatics Training Network (BTN), a new enterprise that has been initiated to address these needs and review...

  18. Resource allocation for relay assisted cognitive radio networks

    KAUST Repository

    Zafar, Ammar

    2012-09-16

    In this paper, we present two optimal resource allocation schemes that maximize throughput and symbol correct rate (SCR). The throughput and SCR are derived. The derived throughput and SCR are optimized with respect to the sensing time, the source transmission power and the relay transmission power. Numerical results show that the optimal sensing time is dependent on the primary user\\'s signal-to-noise-ratio (SNR). They also show that SCR increases with increase in the number of relays. © 2012 IEEE.

  19. Reinforcement learning for resource allocation in LEO satellite networks.

    Science.gov (United States)

    Usaha, Wipawee; Barria, Javier A

    2007-06-01

    In this paper, we develop and assess online decision-making algorithms for call admission and routing for low Earth orbit (LEO) satellite networks. It has been shown in a recent paper that, in a LEO satellite system, a semi-Markov decision process formulation of the call admission and routing problem can achieve better performance in terms of an average revenue function than existing routing methods. However, the conventional dynamic programming (DP) numerical solution becomes prohibited as the problem size increases. In this paper, two solution methods based on reinforcement learning (RL) are proposed in order to circumvent the computational burden of DP. The first method is based on an actor-critic method with temporal-difference (TD) learning. The second method is based on a critic-only method, called optimistic TD learning. The algorithms enhance performance in terms of requirements in storage, computational complexity and computational time, and in terms of an overall long-term average revenue function that penalizes blocked calls. Numerical studies are carried out, and the results obtained show that the RL framework can achieve up to 56% higher average revenue over existing routing methods used in LEO satellite networks with reasonable storage and computational requirements.

  20. Species richness and resource availability: A phylogenetic analysis of insects associated with trees

    OpenAIRE

    Kelly, C. K.; Southwood, T. R. E.

    1999-01-01

    The data on the number of species of insects associated with various trees in Britain have been reanalyzed to factor out possible bias from phylogenetic effects. It was found that tree availability (range and abundance) continues to provide a good predictor (r = 0.852) of insect-species richness, slightly better than straightforward cross-species analyses. Of the two components of tree availability, tree abundance gives a much better prediction than tree range. The species richness on trees o...

  1. Offshore Sand Resource Needs, Data Availability and Revaluation, and Beach Nourishment Projects in North Carolina

    Science.gov (United States)

    Conery, I.; Walsh, J. P.

    2016-12-01

    Storms and sea-level rise continue to impact the dynamic coastlines of North Carolina. Since the coastal region is economically critical to the state and yields numerous ecosystem services, many towns have planned beach nourishment projects. However, offshore sands compatible for nourishment are limited, and project costs fluctuate with borrow source proximity to the shoreline. Hurricane Sandy (2012) caused high water levels and waves resulting in localized overwash and erosion in the northeastern part of NC. In response, to effectively meet the rising nourishment demands for recovery after future storm events and for long-term resiliency, the Bureau of Ocean Energy Management (BOEM) recognized the need to compile and consolidate all geophysical and geologic information in federal waters (3-8 nm) along the East Coast states. A GIS database was created for NC using bathymetric, seismic reflection, sediment and other relevant data from federal, state and private entities. Information will be accessible to the public, coastal planners and managers to allow for informed decision-making and cost-effective project planning. Priority regions for seismic and core collection were determined based on data gaps and needs across the state. In addition, potential sand resource thickness and volume in northeastern NC were revaluated using comparisons of several overlapping datasets. Shoreline volume losses were calculated using long-term erosion rates and compared to historic and future nourishment projects. Finally, tourism-based revenue by town was evaluated and related to short and long-term nourishment costs.

  2. Available web-based teaching resources for health care professionals on screening for oral cancer.

    Science.gov (United States)

    Varela-Centelles, Pablo; Insua, Angel; Seoane-Romero, Juan M; Warnakulasuriya, Saman; Rapidis, Alexander; Diz, Pedro; Seoane, Juan

    2015-03-01

    To identify websites with adequate information on oral cancer screening for healthcare professionals (HCPs) and to assess both their quality and contents. Websites were identified using Google and HON medical professional search engines using the terms "screening for oral cancer". The first 100 sites retrieved by each engine were analysed using the DISCERN questionnaire (reliability), the V instrument (contents on oral cancer) and further by the Flesch-Kinkaid Reading Grade Level and the Flesch Reading Ease (readability). The overall rating showed minimal shortcomings in the quality of the information in the websites. The coverage and correctness of information on "visual examination" was rated as fair/good, whereas updating of contents resulted very variable (eg: 81% for visual examination and 18.2% for molecular biomarkers). These results permitted to rank the websites housing relevant information for oral cancer. Top ranking websites were affiliated to the Oral Cancer Foundation (USA), WHO Collaborating Centre for oral cancer (UK) whose webpage is entitled "Oral Cancer Education and Research", and the Clinical Guidelines maintained by the British Columbia Cancer Agency (Canada) and the British Dental Association (UK) respectively. There are web-based, HCP-addressed, resources on screening for oral cancer housing heterogeneous information both in quality and contents. The use of specific evaluation tools permits the selection of reliable websites on this topic with a potential to improve the existing educational gaps among HCPs.

  3. 75 FR 18547 - Notice of Availability of the Record of Decision for the Carrizo Plain National Monument Resource...

    Science.gov (United States)

    2010-04-12

    ... National Monument (CPNM), located in San Luis Obispo and Kern counties in Central California. The... Bureau of Land Management Notice of Availability of the Record of Decision for the Carrizo Plain National Monument Resource Management Plan/Environmental Impact Statement AGENCY: Bureau of Land Management...

  4. Social networks, work and network-based resources for the management of long-term conditions: a framework and study protocol for developing self-care support

    Directory of Open Access Journals (Sweden)

    Kapadia Dharmi

    2011-05-01

    Full Text Available Abstract Background Increasing the effective targeting and promotion of self-care support for long-term conditions requires more of a focus on patient contexts and networks. The aim of this paper is to describe how within a programme of research and implementation, social networks are viewed as being centrally involved in the mobilisation and deployment of resources in the management of a chronic condition. This forms the basis of a novel approach to understanding, designing, and implementing new forms of self-management support. Methods Drawing on evidence syntheses about social networks and capital and the role of information in self-management, we build on four conceptual approaches to inform the design of our research on the implementation of self-care support for people with long-term conditions. Our approach takes into consideration the form and content of social networks, notions of chronic illness work, normalisation process theory (NPT, and the whole systems informing self-management engagement (WISE approach to self-care support. Discussion The translation and implementation of a self-care agenda in contemporary health and social context needs to acknowledge and incorporate the resources and networks operating in patients' domestic and social environments and everyday lives. The latter compliments the focus on healthcare settings for developing and delivering self-care support by viewing communities and networks, as well as people suffering from long-term conditions, as a key means of support for managing long-term conditions. By focusing on patient work and social-network provision, our aim is to open up a second frontier in implementation research, to translate knowledge into better chronic illness management, and to shift the emphasis towards support that takes place outside formal health services.

  5. Health service availability and health seeking behaviour in resource poor settings: evidence from Mozambique.

    Science.gov (United States)

    Anselmi, Laura; Lagarde, Mylène; Hanson, Kara

    2015-12-01

    Low-income countries are plagued by a high burden of preventable and curable disease as well as unmet need for healthcare, but detailed microeconomic evidence on the relationship between supply-side factors and service use is limited. Causality has rarely been assessed due to the challenges posed by the endogeneity of health service supply.In this study, using data from Mozambique, we investigate the effect of healthcare service availability, measured as the type of health facilities and their level of staffing and equipment, on the individual decision to seek care. We apply an instrumental variable approach to test for causality in the effect of staff and equipment availability on the decision to seek care and we explore heterogeneous effects based on the distance of households to the closest health facility.We find that living in the proximity of a health facility increases the probability of seeking care. A greater availability of referral health services in the locality has no significant effect on decision to seek care, while greater availability of staff and equipment increases the probability of seeking care when ill. Demand side barriers to health care use exist, but have a smaller impact when health care services are available within one hour walking distance.

  6. Optimized Energy Efficiency and Spectral Efficiency Resource Allocation Strategies for Phantom Cellular Networks

    KAUST Repository

    Abdelhady, Amr, M.

    2016-01-06

    Multi-teir hetrogeneous networks have become an essential constituent for next generation cellular networks. Meanwhile, energy efficiency (EE) has been considered a critical design criterion along with the traditional spectral efficiency (SE) metric. In this context, we study power and spectrum allocation for the recently proposed two-teir architecture known as Phantom cellular networks. The optimization framework includes both EE and SE, where we propose an algorithm that computes the SE and EE resource allocation for Phantom cellular networks. Then, we compare the performance of both design strategies versus the number of users, and the ration of Phantom cellresource blocks to the total number or resource blocks. We aim to investigate the effect of some system parameters to acheive improved SE or EE performance at a non-significant loss in EE or SE performance, respectively. It was found that the system parameters can be tuned so that the EE solution does not yield a significant loss in the SE performance.

  7. Social media and colorectal cancer: A systematic review of available resources.

    Science.gov (United States)

    Pellino, Gianluca; Simillis, Constantinos; Qiu, Shengyang; Rasheed, Shahnawaz; Mills, Sarah; Warren, Oliver; Kontovounisios, Christos; Tekkis, Paris P

    2017-01-01

    Social media (SM) can provide information and medical knowledge to patients. Our aim was to review the literature and web-based content on SM that is used by Colorectal Cancer (CRC) patients, as well as surgeons' interaction with SM. Studies published between 2006 and 2016 were assessed. We also assessed the impact of several hashtags on Twitter with a freeware (Symplur). Nine studies were included assessing Twitter (78%), Forums/Cancer-survivor networks (33%), and Facebook (22%). Aims included use of SM by CRC patients (67%), cancer-specific usage of SM with different types of cancer (44%), content credibility (33%), and influence in CRC awareness (33%). Prevention was the most common information that CRC patients looked for, followed by treatment side-effects. Only 2% of CRC SM users are doctors. SM use by colorectal consultants was suboptimal. Only 38% of surgeons had a LinkedIn account (most with less than 50 connections), and 3% used Twitter. A steep increase of tweets was observed for searched Hashtags over time, which was more marked for #ColonCancer (+67%vs+38%, #Coloncancer vs #RectalCancer). Participants engaged with colon cancer increased by 85%, whereas rectal cancer ones increased by 29%. The hashtag '#RectalCancer' was mostly tweeted by colorectal surgeons. The official twitter account of American Society of Colorectal Surgeons (@fascrs_updates) was the most active account. CRC patients and relatives are increasingly engaging with SM. CRC surgeons' participation is poor, but we confirm a trend toward a greater involvement. Most SM lack of authoritative validation and the quality of shared content still is largely anecdotic and not scientifically evidenced-based. However, SM may offer several advantages over conventional information sharing sources for CRC patients and surgeons, and create connections with mutual enrichment.

  8. Radio resource management scheme and outage analysis for network-assisted multi-hop D2D communications

    Directory of Open Access Journals (Sweden)

    Leila Melki

    2016-11-01

    Full Text Available In a cellular network it's very difficult to make spectrum resource more efficiently. Device-to-Device (D2D technology enables new service opportunities, and provides high throughput and reliable communication while reducing the base station load. For better total performance, short-range D2D links and cellular links share the same radio resource and the management of interference becomes a crucial task. Here we argue that single-hop D2D technology can be used to further improve cellular networks performance if the key D2D radio resource management algorithms are suitably extended to support multi-hop D2D communications. Aiming to establish a new paradigm for the analysis and design of multi-hop D2D communications, We propose a radio resource allocation for multi-hop D2D routes based on interference avoidance approach in LTE-A networks. On top of that, we investigate the outage probability of D2D communication. We first introduce a new definition of outage probability by considering the maximum distance to be allowable for single-hop transmission. Then we study and analyze the outage performance of a multi-hop D2D route. We derive the general closed form expression of outage probability of the multi-hop D2D routes. The results demonstrate that the D2D radio, sharing the same resources as the cellular network, provide higher capacity compared to pure cellular communication where all the data is transmitted through the base station. They also demonstrate that the new method of calculation of D2D multi hop outage probability has better performance than classical method defined in the literature.

  9. Radio resource management for mobile traffic offloading in heterogeneous cellular networks

    CERN Document Server

    Wu, Yuan; Huang, Jianwei; Shen, Xuemin (Sherman)

    2017-01-01

    This SpringerBrief offers two concrete design examples for traffic offloading. The first is an optimal resource allocation for small-cell based traffic offloading that aims at minimizing mobile users’ data cost. The second is an optimal resource allocation for device-to-device assisted traffic offloading that also minimizes the total energy consumption and cellular link usage (while providing an overview of the challenging issues). Both examples illustrate the importance of proper resource allocation to the success of traffic offloading, show the consequent performance advantages of executing optimal resource allocation, and present the methodologies to achieve the corresponding optimal offloading solution for traffic offloading in heterogeneous cellular networks. The authors also include an overview of heterogeneous cellular networks and explain different traffic offloading paradigms ranging from uplink traffic offloading through small cells to downlink traffic offloading via mobile device-to-device cooper...

  10. Resources.

    Science.gov (United States)

    Stewart, John; MacDonald, Ian

    1980-01-01

    Presents a guide to resources on television drama available to teachers for classroom use in television curriculum. Lists American and British television drama videorecordings of both series and individual presentations and offers a bibliography of "one-off" single fiction plays produced for British television. (JMF)

  11. Governance for Resilience: CALFED as a Complex Adaptive Network for Resource Management

    Directory of Open Access Journals (Sweden)

    David E. Booher

    2010-09-01

    Full Text Available A study of California's water planning and management process, known as CALFED, offers insights into governance strategies that can deal with adaptive management of environmental resources in ways that conventional bureaucratic procedures cannot. CALFED created an informal policy-making system, engaging multiple agencies and stakeholders. The research is built on data from 5 years of field work that included interviews with participants, review of documents, and observation of meetings. We argue that CALFED can be seen as a self-organizing complex adaptive network (CAN in which interactions were generally guided by collaborative heuristics. The case demonstrates several innovative governance practices, including new practices and norms for interactions among the agents, a distributed structure of information and decision making, a nonlinear planning method, self-organizing system behavior, and adaptation. An example of a resulting policy innovation, a method to provide real-time environmental use of water while protecting a reliable supply of water for agricultural and urban interests, is described. We outline how ideas about complex adaptive network governance differ from ideas about traditional governance. These differences result in ongoing tension and turbulence as they do for other self-organizing governance processes that operate in a context of traditional governance.

  12. Evaluation of Bayesian Networks in Participatory Water Resources Management, Upper Guadiana Basin, Spain

    Directory of Open Access Journals (Sweden)

    Pedro Zorrilla

    2010-09-01

    Full Text Available Stakeholder participation is becoming increasingly important in water resources management. In participatory processes, stakeholders contribute by putting forward their own perspective, and they benefit by enhancing their understanding of the factors involved in decision making. A diversity of modeling tools can be used to facilitate participatory processes. Bayesian networks are well suited to this task for a variety of reasons, including their ability to structure discussions and visual appeal. This research focuses on developing and testing a set of evaluation criteria for public participation. The advantages and limitations of these criteria are discussed in the light of a specific participatory modeling initiative. Modeling work was conducted in the Upper Guadiana Basin in central Spain, where uncontrolled groundwater extraction is responsible for wetland degradation and conflicts between farmers, water authorities, and environmentalists. Finding adequate solutions to the problem is urgent because the implementation of the EU Water Framework Directive requires all aquatic ecosystems to be in a "good ecological state" within a relatively short time frame. Stakeholder evaluation highlights the potential of Bayesian networks to support public participation processes.

  13. Joint Mode Selection and Resource Allocation for Downlink Fog Radio Access Networks Supported D2D

    Directory of Open Access Journals (Sweden)

    Xiang Hongyu

    2015-09-01

    Full Text Available Presented as an innovative paradigm incorporating the cloud computing into radio access network, Cloud radio access networks (C-RANs have been shown advantageous in curtailing the capital and operating expenditures as well as providing better services to the customers. However, heavy burden on the non-ideal fronthaul limits performances of CRANs. Here we focus on the alleviation of burden on the fronthaul via the edge devices’ caches and propose a fog computing based RAN (F-RAN architecture with three candidate transmission modes: device to device, local distributed coordination, and global C-RAN. Followed by the proposed simple mode selection scheme, the average energy efficiency (EE of systems optimization problem considering congestion control is presented. Under the Lyapunov framework, the problem is reformulated as a joint mode selection and resource allocation problem, which can be solved by block coordinate descent method. The mathematical analysis and simulation results validate the benefits of F-RAN and an EE-delay tradeoff can be achieved by the proposed algorithm.

  14. An economic evaluation for an autonomous independent network of distributed energy Resources

    OpenAIRE

    Zoka, Yoshifumi; Sugimoto, Akihiro; Yorino, Naoto; Kawahara, Koji; Kubokawa, Junji

    2007-01-01

    This paper proposes a method for the economic evaluation of an autonomous independent network of distributed energy resources. There are existing proposals for such networks; the system that we are proposing and analyzing in this study is called Microgrid. Microgrid is a new framework of power delivery system that is formed by small, modular generation systems connected to each other to create a small autonomous grid. This paper estimates the total costs to consumers in a Microgrid with optim...

  15. New resource allocation scheme for cognitive relay networks with opportunistic access

    KAUST Repository

    Zafar, Ammar

    2012-06-01

    In this paper, a new resource allocation scheme to minimize Symbol Error rate (SER) for relay assisted cognitive radio networks is studied. A cognitive relay network with amplify-and-forward (AF) fixed gain relays and opportunistic access to the licensed spectrum is considered. The SER objective function and the optimization constraints are derived first. The resource allocation algorithm is then derived using the Langrangian multiplier method. Closed form expressions are derived for the source and relay powers and, symbol time. Analytical results show that the optimal power allocation follows an extended water-filling solution. © 2012 IEEE.

  16. Climate change impact on available water resources obtained using multiple global climate and hydrology models

    NARCIS (Netherlands)

    Hagemann, S.; Chen, Cui; Clark, D.B.; Folwell, S.; Gosling, S.; Haddeland, I.; Hanasaki, N.; Heinke, J.; Ludwig, F.

    2013-01-01

    Climate change is expected to alter the hydrological cycle resulting in large-scale impacts on water availability. However, future climate change impact assessments are highly uncertain. For the first time, multiple global climate (three) and hydrological 5 models (eight) were used to systematically

  17. 75 FR 45673 - Compliance Assistance Resources and Points of Contact Available to Small Businesses

    Science.gov (United States)

    2010-08-03

    ... information is posted on the following Web site: http://www.business.gov/business-law/contacts/federal/ FOR... on the following Web site: http://www.business.gov/business-law/contacts/federal/ . There is also a... U.S.C. 3506(i)(1)). These contacts are also available at http://www.business.gov/business-law...

  18. Insects mediate the effects of propagule supply and resource availability on a plant invasion

    Science.gov (United States)

    Nathan J. Sanders; Jake F. Weltzin; Gregory M. Crutsinger; Matthew C. Fitzpatrick; Martin A. Nunez; Christopher M. Oswalt; Kristin E. Lane

    2007-01-01

    Invasive species are a global threat to biodiversity and the functioning of natural ecosystems. Here, we report on a two-year experiment aimed at elucidating the combined and relative effects of three key controls on plant invasions: propagule supply, soil nitrogen (N) availability, and herbivory by native insects. We focus on the exotic species Lespedeza...

  19. Energy-Efficient Resource Allocation for Phantom Cellular Networks with Imperfect CSI

    KAUST Repository

    Abdelhady, Amr Mohamed Abdelaziz

    2017-03-28

    Multi-tier heterogeneous networks have become an essential constituent for next generation cellular networks. Meanwhile, energy efficiency (EE) has been considered a critical design criterion along with the traditional spectral efficiency (SE) metric. In this context, we study power and spectrum allocation for a two-tier phantom cellular network, The optimization framework includes both EE and SE. We consider densely deployed phantom cellular networks and model the EE optimization problem taking into consideration the inevitable interference in this setup and imperfect channel estimation impairments. To this end, we propose three resource allocation strategies aiming at optimizing this network EE performance metric. Furthermore, we investigate the effect of changing some system parameters on the performance of these strategies, such as phantom cells resource units share, number of deployed phantom cells within a macro cell , number of pilots, and the phantom cells transmission power budget. It is found that increasing the number of pilots will deteriorate the EE performance of the whole setup, while increasing phantom cells transmission power budget will not affect the EE of the whole setup significantly. In addition, we observed that it is always useful to allocate most of the network resource units to the phantom cells tier.

  20. Increased understanding of the cereal phytase complement for better mineral bio-availability and resource management

    DEFF Research Database (Denmark)

    Brinch-Pedersen, Henrik; Madsen, Claus Krogh; Holme, Inger Bæksted

    2014-01-01

    The present paper summarizes the current state of knowledge on cereal phytase that are particular relevant for improving mineral and phosphate bio-availability. Phytases can initiate the hydrolysis of phytate, the main storage form of phosphate in cereals and the major anti-nutritional factor...... for the bio-availability of micronutrients in human nutrition. The composition and levels of mature grain phytase activity (MGPA) in cereals is of central importance for efficient phytate hydrolysis. The MGPA varies considerably between species. Substantial activity is present in Triticeae tribe cereals like...... wheat, barley and rye whereas non-Triticeae cereals such as maize and rice have very little MGPA. Recent studies have determined the evolutionary relationships of phytases in Triticeae and non-Triticeae and highlighted the importance of the purple acid phosphatase phytases (PAPhys). In the Triticeae...

  1. Species richness and resource availability: a phylogenetic analysis of insects associated with trees.

    Science.gov (United States)

    Kelly, C K; Southwood, T R

    1999-07-06

    The data on the number of species of insects associated with various trees in Britain have been reanalyzed to factor out possible bias from phylogenetic effects. It was found that tree availability (range and abundance) continues to provide a good predictor (r = 0. 852) of insect-species richness, slightly better than straightforward cross-species analyses. Of the two components of tree availability, tree abundance gives a much better prediction than tree range. The species richness on trees of major taxa with similar trophic habits (Lepidoptera and Hymenoptera/Symphyta and the two suborders of the Homoptera-Auchenorrhyncha and Sternorrhyncha) shows positive correlations; there is thus no evidence of competitive exclusion at this taxonomic level.

  2. Visualizing Public Opinion in Croatia Based on Available Social Network Content

    Directory of Open Access Journals (Sweden)

    Ševa, Jurica

    2016-01-01

    Full Text Available In the last decade advances of computer technologies have lead towards a technological reality where the line between information consumers and information producers is blurred. This technological omnipresence allows for unprecedented data creation capabilities. Based on various data sources, it seems humans have fully embraced data-generating activities. One such activity is using online social network applications, like Facebook or Twitter in almost all aspects of their lives. One of the main features of online social network applications is perceived freedom of speech, individuality and privacy, even though every application has some special features. Therefore, content generated using these services presents the public with interesting insights in private life of people and their attitudes towards public affairs. Social network applications are active the most during specific public events aimed at the massive public. Due to its brevity, ease of use and frequency, Twitter is an interesting social network application for research and analysis. Other than allowing almost exclusively short messages (up to 140 characters, a tweet (a Twitter post can contain location of the message sender as well as a graphic to accompany the textual message. The textual part of the message may contain so called hashtags – keywords used for indexing and easy identification of a subject the message is related to. These hashtags allow us to group messages related to a specific event. Recent governmental elections held in Croatia were very popular amongst the Croatian Twitter community. Usage of hashtags allowed us to identify the right messages and thus most-used words to describe this event and potentially identify how people felt when talking, i.e. writing, about politics and the held elections. Furthermore, geolocation information, optionally embedded in a tweet, makes it possible to analyze which keywords were used in which parts of Croatia, all pertaining to

  3. Networks, resources and agencies: on the character and production of enabling places.

    Science.gov (United States)

    Duff, Cameron

    2011-01-01

    The study of therapeutic landscapes, restorative places and enabling environments - what might collectively be referred to as enabling places - has revealed much of the relationship between place and health promotion. However, it is arguable that this work has only partially accounted for the diverse therapeutic features of enabling places and the various means of their production. Drawing on Bruno Latour, this paper introduces a conceptual logic of enabling places grounded in the analysis of enabling resources. Three categories of enabling resources will be considered: social, affective and material resources. It will be argued that enabling places are composed in diverse actor-networks, facilitating access to enabling resources and supporting the development of novel agencies or capacities. This draws attention to the various networks and associations that promote health and wellbeing, as well as the resources and agencies necessary to maintain these states. The paper concludes that the analysis of enabling resources, and the networks and agencies that comprise them, provides a novel basis for describing the character and production of enabling places, as well as the diverse benefits associated with them. Copyright © 2010 Elsevier Ltd. All rights reserved.

  4. Determinants of injection drug user (IDU) syringe sharing: the relationship between availability of syringes and risk network member characteristics in Winnipeg, Canada.

    Science.gov (United States)

    Shaw, Souradet Y; Shah, Lena; Jolly, Ann M; Wylie, John L

    2007-10-01

    Despite the establishment of syringe exchange programmes, syringe-sharing behaviour remains common among some injection drug users (IDU). Previous studies have identified several individual- and social network-level variables associated with syringe sharing. We examine the extent to which each of these variables is related independently to this behaviour within a diverse study population. A cross-sectional survey of 435 IDU conducted between December 2003 and September 2004 in Winnipeg, Canada. Individual and social-network variables were obtained from a survey instrument administered through a personal interview. Syringe sharing was defined as receptive syringe sharing in the last 6 months. Logistic regression analysis with generalized estimating equations was used to determine simultaneously the role of individual-level and risk network member-level variables on the odds of syringe sharing. Individuals' relationship to a risk network member (sex partner, OR: 15.3 95% CI: 7.6-30.8; family member, OR: 3.4 95% CI: 1.3-9.0) and difficulty of access to syringes (OR: 3.6 95% CI: 1.3-9.9) were predictive of syringe sharing. Dyads who 'often' pooled resources to obtain drugs were at 4.9 times (95% CI: 2.1-11.6) the odds of syringe sharing, while those who 'sometimes' pooled resources were at 2.8 times (95% CI: 1.1-6.7) the odds, compared to those who 'never' pooled resources together. Syringe sharing in this population depended on both the availability of clean syringes and social network relationships. Adopting interventions that take into account relationships and behaviours that shape social norms present in networks/dyads would be a necessary prevention strategy alongside the provision of clean syringes.

  5. Predation cues rather than resource availability promote cryptic behaviour in a habitat-forming sea urchin.

    Science.gov (United States)

    Spyksma, Arie J P; Taylor, Richard B; Shears, Nick T

    2017-03-01

    It is well known that predators often influence the foraging behaviour of prey through the so-called "fear effect". However, it is also possible that predators could change prey behaviour indirectly by altering the prey's food supply through a trophic cascade. The predator-sea urchin-kelp trophic cascade is widely assumed to be driven by the removal of sea urchins by predators, but changes in sea urchin behaviour in response to predators or increased food availability could also play an important role. We tested whether increased crevice occupancy by herbivorous sea urchins in the presence of abundant predatory fishes and lobsters is a response to the increased risk of predation, or an indirect response to higher kelp abundances. Inside two New Zealand marine reserves with abundant predators and kelp, individuals of the sea urchin Evechinus chloroticus were rarer and remained cryptic (i.e. found in crevices) to larger sizes than on adjacent fished coasts where predators and kelp are rare. In a mesocosm experiment, cryptic behaviour was induced by simulated predation (the addition of crushed conspecifics), but the addition of food in the form of drift kelp did not induce cryptic behaviour. These findings demonstrate that the 'fear' of predators is more important than food availability in promoting sea urchin cryptic behaviour and suggest that both density- and behaviourally mediated interactions are important in the predator-sea urchin-kelp trophic cascade.

  6. Fluoride availability from natural resources in The Gambia--implications for oral health care.

    Science.gov (United States)

    Jordan, Rainer A; Markovic, Ljubisa; Gaengler, Peter

    2008-10-01

    Changing food patterns in combination with ineffective oral hygiene measures and insufficient bioavailability of fluoride from drinking water and other sources seem to impair the dental health status in developing countries, especially in the younger population. Therefore, preventive programmes in controlling dental caries progression should be based on local conditions. For mapping the drinking water fluoride content throughout The Gambia, samples of water from rural community wells, public water taps, commercial mineral water, and from the Gambia-River were measured. Additionally, fluoride concentrations of locally extracted table salt and green tea were determined. Showed the need for supplementary fluoride intake, because natural dietary fluoride availability is very low. Age-related recommendations for oral health care and for additional fluoride bioavailability are given, taking into account local socio-economic conditions in the Republic of The Gambia and similar developing countries.

  7. School nutritional capacity, resources and practices are associated with availability of food/beverage items in schools

    Science.gov (United States)

    2013-01-01

    Background The school food environment is important to target as less healthful food and beverages are widely available at schools. This study examined whether the availability of specific food/beverage items was associated with a number of school environmental factors. Methods Principals from elementary (n = 369) and middle/high schools (n = 118) in British Columbia (BC), Canada completed a survey measuring characteristics of the school environment. Our measurement framework integrated constructs from the Theories of Organizational Change and elements from Stillman’s Tobacco Policy Framework adapted for obesity prevention. Our measurement framework included assessment of policy institutionalization of nutritional guidelines at the district and school levels, climate, nutritional capacity and resources (nutritional resources and participation in nutritional programs), nutritional practices, and school community support for enacting stricter nutritional guidelines. We used hierarchical mixed-effects logistic regression analyses to examine associations with the availability of fruit, vegetables, pizza/hamburgers/hot dogs, chocolate candy, sugar-sweetened beverages, and french fried potatoes. Results In elementary schools, fruit and vegetable availability was more likely among schools that have more nutritional resources (OR = 6.74 and 5.23, respectively). In addition, fruit availability in elementary schools was highest in schools that participated in the BC School Fruit and Vegetable Nutritional Program and the BC Milk program (OR = 4.54 and OR = 3.05, respectively). In middle/high schools, having more nutritional resources was associated with vegetable availability only (OR = 5.78). Finally, middle/high schools that have healthier nutritional practices (i.e., which align with upcoming provincial/state guidelines) were less likely to have the following food/beverage items available at school: chocolate candy (OR = .80) and sugar

  8. School nutritional capacity, resources and practices are associated with availability of food/beverage items in schools.

    Science.gov (United States)

    Mâsse, Louise C; de Niet, Judith E

    2013-02-19

    The school food environment is important to target as less healthful food and beverages are widely available at schools. This study examined whether the availability of specific food/beverage items was associated with a number of school environmental factors. Principals from elementary (n=369) and middle/high schools (n=118) in British Columbia (BC), Canada completed a survey measuring characteristics of the school environment. Our measurement framework integrated constructs from the Theories of Organizational Change and elements from Stillman's Tobacco Policy Framework adapted for obesity prevention. Our measurement framework included assessment of policy institutionalization of nutritional guidelines at the district and school levels, climate, nutritional capacity and resources (nutritional resources and participation in nutritional programs), nutritional practices, and school community support for enacting stricter nutritional guidelines. We used hierarchical mixed-effects logistic regression analyses to examine associations with the availability of fruit, vegetables, pizza/hamburgers/hot dogs, chocolate candy, sugar-sweetened beverages, and french fried potatoes. In elementary schools, fruit and vegetable availability was more likely among schools that have more nutritional resources (OR=6.74 and 5.23, respectively). In addition, fruit availability in elementary schools was highest in schools that participated in the BC School Fruit and Vegetable Nutritional Program and the BC Milk program (OR=4.54 and OR=3.05, respectively). In middle/high schools, having more nutritional resources was associated with vegetable availability only (OR=5.78). Finally, middle/high schools that have healthier nutritional practices (i.e., which align with upcoming provincial/state guidelines) were less likely to have the following food/beverage items available at school: chocolate candy (OR= .80) and sugar-sweetened beverages (OR= .76). School nutritional capacity, resources

  9. Sensitivity Study on Availability of I&C Components Using Bayesian Network

    Directory of Open Access Journals (Sweden)

    Rahman Khalil Ur

    2013-01-01

    Full Text Available The objective of this study is to find out the impact of instrumentation and control (I&C components on the availability of I&C systems in terms of sensitivity analysis using Bayesian network. The analysis has been performed on I&C architecture of reactor protection system. The analysis results would be applied to develop I&C architecture which will meet the desire reliability features and save cost. RPS architecture unavailability P(x=0 and availability P(x=1 were estimated to 6.1276E-05 and 9.9994E-01 for failure (0 and perfect (1 states, respectively. The impact of I&C components on overall system risk has been studied in terms of risk achievement worth (RAW and risk reduction worth (RRW. It is found that circuit breaker failure (TCB, bi-stable processor (BP, sensor transmitter (TR, and pressure transmitter (PT have high impact on risk. The study concludes and recommends that circuit breaker bi-stable processor should be given more consideration while designing I&C architecture.

  10. Influences of Climate Change on Water Resources Availability of Costal Basins in Southeast China: a Case Study in Jinjiang Basin

    Science.gov (United States)

    Yao, Xiaolei; Yu, Jingshan; Li, Zhanjie; Sun, Wenchao

    2014-05-01

    In this study, the influences of climate change on water resources availability in a costal basin in southeast China, Jinjiang Basin, were assessed using the Block-wise use of the TOPmodel with the Muskingum-Cunge routing method (BTOPMC) distributed hydrological model. The ensemble average of downscaled output from sixteen GCMs for A1B emission scenario in 2050s was adopted to build regional climate change scenario. After calibration and validation for model parameters, the result of streamflow simulation proves that this BTOPMC hydrological model is applicable to this basin. Then the projected precipitation and temperature data were used to drive BTOPMC for predicting hydrological changes in 2050s. The evaluation of water resources available was carried out based on the simulation of streamflow in the downstream Shilong hydrologic station. Result shows that evapotranspiration will increase in most time of a year. Runoff in summer to early autumn exhibits an increasing trend. While in the rest period runoff show a decreasing trend, especially in spring season. From the perspective of water resource availability, it is indicated that the water resources may not be sufficient to meet the irrigation water demand in the spring season and one possible solution is to store more water in the reservoir in previous summer. The results of this study may benefit for making reasonable water resource management policy in the Jinjiang Basin. To make the policy in a more quantitive manner, an analysis about the amount of water needed for the whole basin is needed to decide how much extra water should be stored in the summer season.

  11. Advances in the genetic dissection of plant cell walls: tools and resources available in Miscanthus

    Directory of Open Access Journals (Sweden)

    Gancho eSlavov

    2013-07-01

    Full Text Available Tropical C4 grasses from the genus Miscanthus are believed to have great potential as biomass crops. However, Miscanthus species are essentially undomesticated, and genetic, molecular and bioinformatics tools are in very early stages of development. Furthermore, similar to other crops targeted as lignocellulosic feedstocks, the efficient utilisation of biomass is hampered by our limited knowledge of the structural organisation of the plant cell wall and the underlying genetic components that control this organisation. The Institute of Biological, Environmental and Rural Sciences (IBERS has assembled an extensive collection of germplasm for several species of Miscanthus. In addition, an integrated, multidisciplinary research programme at IBERS aims to inform accelerated breeding for biomass productivity and composition, while also generating novel fundamental knowledge. Here we review recent advances with respect to the genetic characterisation of the cell wall in Miscanthus. First, we present a summary of recent and on-going biochemical studies, including prospects and limitations for the development of powerful phenotyping approaches. Second, we review current knowledge about genetic variation for cell wall characteristics of Miscanthus and illustrate how phenotypic data, combined with high-density arrays of single nucleotide polymorphisms, are being used in genome-wide association studies to generate testable hypotheses and guide biological discovery. Finally, we provide an overview of the current knowledge about the molecular biology of cell wall biosynthesis in Miscanthus and closely related grasses, discuss the key conceptual and technological bottlenecks, and outline the short-term prospects for progress in this field.

  12. Growth and chemical defense in relation to resource availability: tradeoffs or common responses to environmental stress?

    Directory of Open Access Journals (Sweden)

    J. S. Almeida-Cortez

    Full Text Available One aspect of plant defense is the production of constitutive secondary compounds that confer toxicity on herbivores and pathogens. The purpose of this study was to compare patterns of plant tissue toxicity across gradients of irradiance and nutrient content. We measured the potential toxicity (1/LC50 of extracts of six species of herbaceous Asteraceae grown under controlled conditions of temperature (25ºC, humidity (80%, photoperiod (16 h/day, in a range of concentrations of a modified Hoagland hydroponic solution (full-strength, 1/5 dilute, 1/10 dilute, and 1/50 dilute and under two different light intensities (250 and 125 mumol/m²/s. The plants grew from seed for 42 days post-germination, and randomly chosen plants were harvested each 7 days. We did a general measure of potential phytochemical toxicity using an alcohol extraction of secondary compounds followed by brine shrimp (Artemia sp. bioassay. Contrary to the carbon/nutrient balance hypothesis, tissue toxicity generally increased with decreasing irradiance and nutrient levels, so that plants whose growth was most restricted had tissues that were most toxic, although there were species-specific differences in this trend.

  13. Resource Allocation for OFDMA Two-Hope Cooperative Cellular Networks: Considering QoS and Fairness Constraints

    Directory of Open Access Journals (Sweden)

    Hamed Bani Zaman

    2014-04-01

    Full Text Available Joint bit allocation, relay selection and subcarrier assignment are critical for achieving full benefits of OFDM-based cooperative relay networks. In this paper, first such a problem is studied in a dual hop OFDMA cooperative network consisting in multi source nodes, multiple decode-and-forward (DF relays and a single destination node. The aim is to minimize overall transmission power under the bit-error-rate (BER and data rate constraints. However, the optimal solution to the optimization problem is computationally complex to obtain and may be unfair. Assuming knowledge of the instantaneous channel gains for all links in the entire network, an iterative three-step resource allocation algorithm with low complexity is proposed. It performs the privileged user selection based on fairness criterion first, and then allocates subcarrier-relay with the given constraints. Finally, power and bit are assigned to the selected subcarriers based on the water-filling algorithm. In order to guarantee the fairness of users, several fairness criteria are also proposed to provide attractive trade-offs between network performance (i.e. overall transmission power, average network lifetime and average outage probability and fairness to all users. Numerical studies are conducted to evaluate the performance of the proposed algorithm in two practical scenarios. Simulation results show that the proposed allocation algorithm achieves an efficient trade-off between network performance and fairness among users.

  14. ONLINE SOCIAL NETWORKS AS A TOOL FOR THE PROMOTION OF PHYSICAL ACTIVITY AND HEALTH: A RESOURCE SCIENTIFICALLY FEW EXPLORED

    Directory of Open Access Journals (Sweden)

    Arían Ramón Aladro Gonzalvo

    2015-06-01

    Full Text Available Due to the great impact  that are exerting the networks in society, it is crucial to know the features that distinguish online social networks bringing together users interested in receiving information and resources to improve or maintain the body in shape. This article aims to comment on the limited research interested in studying the features and particularities of online communities that provide information, advice and support in the execution, performance and promotion of the health and fitness activities. Particularly, it underline about the necessity to know of networks structure, user profiles and peer-to-peer interaction, sort of membership, mechanisms of communication, representation of the body image and patterns of association. Likewise, the size of the support networks, telepresence, technology acceptance and perceived risk on the network. Besides, we recommend exploring two Fitness-related online social networks. Finally, it makes known the recurring problems in the analysis in order to characterize psychosocial and communicative aspects of users in the virtual environment.

  15. Multi-agent modelling framework for water, energy and other resource networks

    Science.gov (United States)

    Knox, S.; Selby, P. D.; Meier, P.; Harou, J. J.; Yoon, J.; Lachaut, T.; Klassert, C. J. A.; Avisse, N.; Mohamed, K.; Tomlinson, J.; Khadem, M.; Tilmant, A.; Gorelick, S.

    2015-12-01

    Bespoke modelling tools are often needed when planning future engineered interventions in the context of various climate, socio-economic and geopolitical futures. Such tools can help improve system operating policies or assess infrastructure upgrades and their risks. A frequently used approach is to simulate and/or optimise the impact of interventions in engineered systems. Modelling complex infrastructure systems can involve incorporating multiple aspects into a single model, for example physical, economic and political. This presents the challenge of combining research from diverse areas into a single system effectively. We present the Pynsim 'Python Network Simulator' framework, a library for building simulation models capable of representing, the physical, institutional and economic aspects of an engineered resources system. Pynsim is an open source, object oriented code aiming to promote integration of different modelling processes through a single code library. We present two case studies that demonstrate important features of Pynsim's design. The first is a large interdisciplinary project of a national water system in the Middle East with modellers from fields including water resources, economics, hydrology and geography each considering different facets of a multi agent system. It includes: modelling water supply and demand for households and farms; a water tanker market with transfer of water between farms and households, and policy decisions made by government institutions at district, national and international level. This study demonstrates that a well-structured library of code can provide a hub for development and act as a catalyst for integrating models. The second focuses on optimising the location of new run-of-river hydropower plants. Using a multi-objective evolutionary algorithm, this study analyses different network configurations to identify the optimal placement of new power plants within a river network. This demonstrates that Pynsim can be

  16. Physical and Cross-Layer Security Enhancement and Resource Allocation for Wireless Networks

    Science.gov (United States)

    Bashar, Muhammad Shafi Al

    2011-01-01

    In this dissertation, we present novel physical (PHY) and cross-layer design guidelines and resource adaptation algorithms to improve the security and user experience in the future wireless networks. Physical and cross-layer wireless security measures can provide stronger overall security with high efficiency and can also provide better…

  17. An adaptive resource control mechanism in multi-hop ad-hoc networks

    NARCIS (Netherlands)

    Yang, Y.; Heijenk, Geert; Haverkort, Boudewijn R.H.M.; Masip Bruin, Xavier; Verchere, Dominique; Tsaoussidis, Vassilis; Yannuzzi, Marcelo

    This paper presents an adaptive resource control mechanism for multi-hop ad-hoc network systems, which avoids bottleneck problems caused by the node-fairness property of IEEE 802.11. In our proposal, the feedback information from the downstream bottleneck, derived from Request-To-Send (RTS) and

  18. XACML policy profile for multidomain network resource provisioning and supporting authorisation infrastructure

    NARCIS (Netherlands)

    Demchenko, Y.; Cristea, M.; de Laat, C.

    2009-01-01

    Policy definition is an important component of the consistent authorisation service infrastructure that could be effectively integrated with the general resource provisioning workflow and network control and management plane. The paper describes the proposed XACML-NRP policy and attributes profile

  19. Fairness and resource allocation in device-to-device wireless regional area network

    NARCIS (Netherlands)

    Shi, H.

    2014-01-01

    With the rapid development in wireless devices, applications and networks, radio frequencies have become scarce resources. Therefore, it is critical to make efficient use of the radio frequencies. A promising way to solve this problem is the use of cognitive radio (CR). In CR, radio frequencies are

  20. Resource-based interdependencies in value networks for mobile Internet services

    NARCIS (Netherlands)

    Montalvo, U.W. de; Kar, E. van de; Maitland, C.

    2004-01-01

    The advent of new electronic platforms, such as fixed and mobile Internet, is forcing firms from a range of industries to come together in so-called 'value networks' for the provision of innovative services. Firms from different industries have widely varying resources. Our analysis is aimed at

  1. A centralized feedback control model for resource management in wireless networks

    NARCIS (Netherlands)

    Yang, Y.; Haverkort, Boudewijn R.H.M.; Heijenk, Geert

    In a wireless environment, guaranteeing QoS is challenging because applications at multiple devices share the same limited radio bandwidth. In this paper we introduce and study a resource management model for centralized wireless networks, using feedback control theory. Before applying in practice,

  2. Biobjective Optimization of Radio Access Technology Selection and Resource Allocation in Heterogeneous Wireless Networks

    DEFF Research Database (Denmark)

    Zakrzewska, Anna; D’Andreagiovanni, Fabio; Ruepp, Sarah Renée

    2013-01-01

    We propose a novel optimization model for resource assignment in heterogeneous wireless network. The model adopts two objective functions maximizing the number of served users and the minimum granted utility at once. A distinctive feature of our new model is to consider two consecutive time slots...

  3. RAT Selection and Resource Allocation in Heterogeneous Networks - OPNET Modeler in Optimization Studies

    DEFF Research Database (Denmark)

    Zakrzewska, Anna; Ruepp, Sarah Renée; Berger, Michael Stübert

    2013-01-01

    The paper addresses the problem of optimal selection of Radio Access Technology (RAT) and assignment of resources in a multistandard wireless network scenario. It is shown how OPNET Modeler can be used to perform optimization studies using Integer Linear Programming (ILP) solvers. In this way...

  4. Agro-Economic Design of Cropping Pattern in Hendijan Irrigation and Drainage Network with Emphasis on Water Resources

    Directory of Open Access Journals (Sweden)

    A Madeh Khaksar

    2012-02-01

    Full Text Available Recently, design of cropping pattern based on water resources is getting a high priority. This scheme is complicated, and affected by multiple factors. For investigation, designer must gather a huge data, and classify them. The method of processing and analyzing of the information is important. The method of linear programming based on Lingo software for Hendijan irrigation and drainage network was used. On the basis of water resources situation, physical limitations, ecology and economical parameters, hydromodule was determined. The model with initial data for crop pattern is performed by software to produce projected hydromodule. In this survey, sensitivity analysis on water cost was conducted. Result showed that by increasing water cost and rotation intensity, revenue for each consumption water unit was decreased. The maximum benefit for all available conditions of water on the case of non intensity would be 140 percent, for 3% of crops. The maximum benefit was 133346682 Rls per hectare based on water availability for 2006.

  5. Seasonal availability of edible underground and aboveground carbohydrate resources to human foragers on the Cape south coast, South Africa

    Directory of Open Access Journals (Sweden)

    Jan C. De Vynck

    2016-02-01

    Full Text Available The coastal environments of South Africa’s Cape Floristic Region (CFR provide some of the earliest and most abundant evidence for the emergence of cognitively modern humans. In particular, the south coast of the CFR provided a uniquely diverse resource base for hunter-gatherers, which included marine shellfish, game, and carbohydrate-bearing plants, especially those with Underground Storage Organs (USOs. It has been hypothesized that these resources underpinned the continuity of human occupation in the region since the Middle Pleistocene. Very little research has been conducted on the foraging potential of carbohydrate resources in the CFR. This study focuses on the seasonal availability of plants with edible carbohydrates at six-weekly intervals over a two-year period in four vegetation types on South Africa’s Cape south coast. Different plant species were considered available to foragers if the edible carbohydrate was directly (i.e. above-ground edible portions or indirectly (above-ground indications to below-ground edible portions visible to an expert botanist familiar with this landscape. A total of 52 edible plant species were recorded across all vegetation types. Of these, 33 species were geophytes with edible USOs and 21 species had aboveground edible carbohydrates. Limestone Fynbos had the richest flora, followed by Strandveld, Renosterveld and lastly, Sand Fynbos. The availability of plant species differed across vegetation types and between survey years. The number of available USO species was highest for a six-month period from winter to early summer (Jul–Dec across all vegetation types. Months of lowest species’ availability were in mid-summer to early autumn (Jan–Apr; the early winter (May–Jun values were variable, being highest in Limestone Fynbos. However, even during the late summer carbohydrate “crunch,” 25 carbohydrate bearing species were visible across the four vegetation types. To establish a robust resource

  6. Structure analysis and core community detection of embodied resources networks among regional industries

    Science.gov (United States)

    He, Xijun; Dong, Yanbo; Wu, Yuying; Wei, Guodan; Xing, Lizhi; Yan, Jia

    2017-08-01

    To address the double pressure of scarce resources and regional industrial isomorphism, this paper applied the concepts of exergy and embodied resources based on economic input-output (I-O) data. We constructed the embodied resources networks among the regional industries of Beijing-Tianjin-Hebei (also known as Jing-Jin-Ji) in China. We analyzed the rules of embodied resources consumption in the area's industries, identified the core community structures, and studied the characteristics of industrial homogeneity through regional comparisons. The results showed that the dependence on scarce resources of industrial operations in Beijing was less than in Jin-Ji, while the dependence on finance, technology, information, and other service resources in Beijing was higher than in Jin-Ji. The I-O efficiency of embodied resources among industries and the agglomeration of correlation relationships in industries with large embodied resources were higher than in Jin-Ji. The industrial coincidence degree in the ;bridge; industries and in the core community in Jin-Ji was higher than in Jing-Jin and Jing-Ji, which means the industrial homogeneous competition of Jin-Ji was higher, too. This study makes a significant contribution toward promoting the dislocation development of regional industries, accelerating the coordination of resources, and reducing homogeneity competition.

  7. Availability of Network Psychiatrists Among the Largest Health Insurance Carriers in Washington, D.C.

    Science.gov (United States)

    Blech, Benzion; West, Joyce C; Yang, Zhuoyin; Barber, Keila D; Wang, Philip; Coyle, Colleen

    2017-09-01

    Lack of access to mental health treatment remains a significant problem in the United States, even after implementation of mental health parity legislation. This study examined availability of psychiatrists listed in insurance carrier network provider databases in the Washington, D.C., area. Contact information was obtained for 1,184 psychiatrists listed in online directories for three of the largest insurance carriers serving the Washington, D.C., area. The "mystery shopper" method was used to assess the accuracy of listed contact information, new outpatient appointment availability, and average wait times for 50 psychiatrists randomly selected from each insurance directory. Most (77%) physicians were successfully contacted, meaning that someone answered the phone or returned a voice mail message, and 51% of the psychiatrists had working telephone numbers verified to be correct. Fifteen percent of the psychiatrists were accepting new outpatients with the target insurance, with average wait times of 19 days; only 7% were able to schedule an appointment within two weeks. Inaccuracy of insurance provider directories significantly affected the ability of patients to obtain timely mental care.

  8. Efficient Pricing Technique for Resource Allocation Problem in Downlink OFDM Cognitive Radio Networks

    Science.gov (United States)

    Abdulghafoor, O. B.; Shaat, M. M. R.; Ismail, M.; Nordin, R.; Yuwono, T.; Alwahedy, O. N. A.

    2017-05-01

    In this paper, the problem of resource allocation in OFDM-based downlink cognitive radio (CR) networks has been proposed. The purpose of this research is to decrease the computational complexity of the resource allocation algorithm for downlink CR network while concerning the interference constraint of primary network. The objective has been secured by adopting pricing scheme to develop power allocation algorithm with the following concerns: (i) reducing the complexity of the proposed algorithm and (ii) providing firm power control to the interference introduced to primary users (PUs). The performance of the proposed algorithm is tested for OFDM- CRNs. The simulation results show that the performance of the proposed algorithm approached the performance of the optimal algorithm at a lower computational complexity, i.e., O(NlogN), which makes the proposed algorithm suitable for more practical applications.

  9. Seasonal availability of edible underground and aboveground carbohydrate resources to human foragers on the Cape south coast, South Africa

    Science.gov (United States)

    Cowling, Richard M.; Potts, Alastair J.; Marean, Curtis W.

    2016-01-01

    The coastal environments of South Africa’s Cape Floristic Region (CFR) provide some of the earliest and most abundant evidence for the emergence of cognitively modern humans. In particular, the south coast of the CFR provided a uniquely diverse resource base for hunter-gatherers, which included marine shellfish, game, and carbohydrate-bearing plants, especially those with Underground Storage Organs (USOs). It has been hypothesized that these resources underpinned the continuity of human occupation in the region since the Middle Pleistocene. Very little research has been conducted on the foraging potential of carbohydrate resources in the CFR. This study focuses on the seasonal availability of plants with edible carbohydrates at six-weekly intervals over a two-year period in four vegetation types on South Africa’s Cape south coast. Different plant species were considered available to foragers if the edible carbohydrate was directly (i.e. above-ground edible portions) or indirectly (above-ground indications to below-ground edible portions) visible to an expert botanist familiar with this landscape. A total of 52 edible plant species were recorded across all vegetation types. Of these, 33 species were geophytes with edible USOs and 21 species had aboveground edible carbohydrates. Limestone Fynbos had the richest flora, followed by Strandveld, Renosterveld and lastly, Sand Fynbos. The availability of plant species differed across vegetation types and between survey years. The number of available USO species was highest for a six-month period from winter to early summer (Jul–Dec) across all vegetation types. Months of lowest species’ availability were in mid-summer to early autumn (Jan–Apr); the early winter (May–Jun) values were variable, being highest in Limestone Fynbos. However, even during the late summer carbohydrate “crunch,” 25 carbohydrate bearing species were visible across the four vegetation types. To establish a robust resource landscape

  10. The relative influence of available resources during the residency match: a national survey of canadian medical students.

    Science.gov (United States)

    Blissett, Sarah; Law, Christine; Morra, Dante; Ginsburg, Shiphra

    2011-12-01

    Many medical students find choosing a residency challenging. There are several steps involved, including determining one's own priorities, arranging electives, choosing a training program and site, and preparing an in-depth application and a rank order list. Many resources are available to assist students, including the Canadian Resident Matching Service website, program websites, career counselors, career information sessions, mentors, peers, family/friends, and the Canadian Medical Residency Guide. Our study explored the relative impact of these resources on the career decision-making process. We invited medical students in their final year at 12 Canadian medical schools to complete an online survey. Questions included identifying the relative utility of resources in the context of each component of the decision-making process. Responses were analyzed using descriptive statistics. The response rate was 71% (1076 of 1518). Overall, mentors, family/friends, and peers had the most impact on students' decision making. Career counselors, websites, and the Canadian Medical Residency Guide had much less impact. Family/friends were most frequently cited as essential to the process; however, family/friends and peers were equal in having some impact. Our findings suggest that students are most influenced by family, friends, and peers, who are not involved in the formal residency selection effort. Appreciating the impact of these influences on students' decision making is important to understanding how they decide on their future careers. The study supports continuation of mentorship programs. Future work could focus on qualitative research to further characterize resource use.

  11. Using economic valuation techniques to inform water resources management: a survey and critical appraisal of available techniques and an application.

    Science.gov (United States)

    Birol, Ekin; Karousakis, Katia; Koundouri, Phoebe

    2006-07-15

    The need for economic analysis for the design and implementation of efficient water resources management policies is well documented in the economics literature. This need is also emphasised in the European Union's recent Water Framework Directive (2000/60/EC), and is relevant to the objectives of Euro-limpacs, an EU funded project which inter alia, aims to provide a decision-support system for valuing the effects of future global change on Europe's freshwater ecosystems. The purpose of this paper is to define the role of economic valuation techniques in assisting in the design of efficient, equitable and sustainable policies for water resources management in the face of environmental problems such as pollution, intensive land use in agriculture and climate change. The paper begins with a discussion of the conceptual economic framework that can be used to inform water policy-making. An inventory of the available economic valuation methods is presented and the scope and suitability of each for studying various aspects of water resources are critically discussed. Recent studies that apply these methods to water resources are reviewed. Finally, an application of one of the economic valuation methods, namely the contingent valuation method, is presented using a case study of the Cheimaditida wetland in Greece.

  12. Cost and Availability Analysis of 2- and 3-Connected WDM Networks Physical Interconnection

    DEFF Research Database (Denmark)

    Gutierrez Lopez, Jose Manuel; Riaz, M. Tahir; Pedersen, Jens Myrup

    2012-01-01

    Our future in personal and professional lives is becoming more attached to the evolution of communication technologies and their applications. Consequently, the way Next Generation Network are currently being planned and deployed, might have a great impact on common people depending on how networks...... for the best trade-off among the relevant parameters for the network. In this paper we analyze this trade-off by studying 2-and 3-connected graphs to be used as WDM (Wavelength Division Multiplexing) networks physical infrastructure. The experiments show how the way links are distributed to interconnect...

  13. A review of the methods available for estimating soil moisture and its implications for water resource management

    Science.gov (United States)

    Dobriyal, Pariva; Qureshi, Ashi; Badola, Ruchi; Hussain, Syed Ainul

    2012-08-01

    SummaryThe maintenance of elevated soil moisture is an important ecosystem service of the natural ecosystems. Understanding the patterns of soil moisture distribution is useful to a wide range of agencies concerned with the weather and climate, soil conservation, agricultural production and landscape management. However, the great heterogeneity in the spatial and temporal distribution of soil moisture and the lack of standard methods to estimate this property limit its quantification and use in research. This literature based review aims to (i) compile the available knowledge on the methods used to estimate soil moisture at the landscape level, (ii) compare and evaluate the available methods on the basis of common parameters such as resource efficiency, accuracy of results and spatial coverage and (iii) identify the method that will be most useful for forested landscapes in developing countries. On the basis of the strengths and weaknesses of each of the methods reviewed we conclude that the direct method (gravimetric method) is accurate and inexpensive but is destructive, slow and time consuming and does not allow replications thereby having limited spatial coverage. The suitability of indirect methods depends on the cost, accuracy, response time, effort involved in installation, management and durability of the equipment. Our review concludes that measurements of soil moisture using the Time Domain Reflectometry (TDR) and Ground Penetrating Radar (GPR) methods are instantaneously obtained and accurate. GPR may be used over larger areas (up to 500 × 500 m a day) but is not cost-effective and difficult to use in forested landscapes in comparison to TDR. This review will be helpful to researchers, foresters, natural resource managers and agricultural scientists in selecting the appropriate method for estimation of soil moisture keeping in view the time and resources available to them and to generate information for efficient allocation of water resources and

  14. Sophisticated Online Learning Scheme for Green Resource Allocation in 5G Heterogeneous Cloud Radio Access Networks

    KAUST Repository

    Alqerm, Ismail

    2018-01-23

    5G is the upcoming evolution for the current cellular networks that aims at satisfying the future demand for data services. Heterogeneous cloud radio access networks (H-CRANs) are envisioned as a new trend of 5G that exploits the advantages of heterogeneous and cloud radio access networks to enhance spectral and energy efficiency. Remote radio heads (RRHs) are small cells utilized to provide high data rates for users with high quality of service (QoS) requirements, while high power macro base station (BS) is deployed for coverage maintenance and low QoS users service. Inter-tier interference between macro BSs and RRHs and energy efficiency are critical challenges that accompany resource allocation in H-CRANs. Therefore, we propose an efficient resource allocation scheme using online learning, which mitigates interference and maximizes energy efficiency while maintaining QoS requirements for all users. The resource allocation includes resource blocks (RBs) and power. The proposed scheme is implemented using two approaches: centralized, where the resource allocation is processed at a controller integrated with the baseband processing unit and decentralized, where macro BSs cooperate to achieve optimal resource allocation strategy. To foster the performance of such sophisticated scheme with a model free learning, we consider users\\' priority in RB allocation and compact state representation learning methodology to improve the speed of convergence and account for the curse of dimensionality during the learning process. The proposed scheme including both approaches is implemented using software defined radios testbed. The obtained results and simulation results confirm that the proposed resource allocation solution in H-CRANs increases the energy efficiency significantly and maintains users\\' QoS.

  15. Tree spatial structure, host composition and resource availability influence mirid density or black pod prevalence in cacao agroforests in Cameroon.

    Directory of Open Access Journals (Sweden)

    Cynthia Gidoin

    Full Text Available Combining crop plants with other plant species in agro-ecosystems is one way to enhance ecological pest and disease regulation mechanisms. Resource availability and microclimatic variation mechanisms affect processes related to pest and pathogen life cycles. These mechanisms are supported both by empirical research and by epidemiological models, yet their relative importance in a real complex agro-ecosystem is still not known. Our aim was thus to assess the independent effects and the relative importance of different variables related to resource availability and microclimatic variation that explain pest and disease occurrence at the plot scale in real complex agro-ecosystems. The study was conducted in cacao (Theobroma cacao agroforests in Cameroon, where cocoa production is mainly impacted by the mirid bug, Sahlbergella singularis, and black pod disease, caused by Phytophthora megakarya. Vegetation composition and spatial structure, resource availability and pest and disease occurrence were characterized in 20 real agroforest plots. Hierarchical partitioning was used to identify the causal variables that explain mirid density and black pod prevalence. The results of this study show that cacao agroforests can be differentiated on the basis of vegetation composition and spatial structure. This original approach revealed that mirid density decreased when a minimum number of randomly distributed forest trees were present compared with the aggregated distribution of forest trees, or when forest tree density was low. Moreover, a decrease in mirid density was also related to decreased availability of sensitive tissue, independently of the effect of forest tree structure. Contrary to expectations, black pod prevalence decreased with increasing cacao tree abundance. By revealing the effects of vegetation composition and spatial structure on mirids and black pod, this study opens new perspectives for the joint agro-ecological management of cacao pests

  16. Novel methodology for optimal reconfiguration of distribution networks with distributed energy resources

    DEFF Research Database (Denmark)

    Chittur Ramaswamy, Parvathy; Tant, Jeroen; Pillai, Jayakrishnan Radhakrishna

    2015-01-01

    This paper develops three novel methodologies for optimal reconfiguration of distribution networks in the presence of distributed energy resources (DERs). The novelty is in achieving a non-conservative and robust solution to grid reconfiguration. The optimal solution is the minimum......-loss-configuration of the distribution network taking into account the cost of switching and the grid operational constraints. The methods are based on the concepts of receding horizon control (RHC) and scenario analysis (SA) which inherently optimize switching costs and losses. The salient feature of incorporating RHC and SA...... of the distribution network since they indicate the most frequently open switches in the network and the time at which they are to be operated....

  17. A network-centric robust resource allocation strategy for unmanned systems: stability analysis

    Science.gov (United States)

    Bouyoucef, K.; Khorasani, K.

    2007-04-01

    It is widely understood that communication is a critical technological factor in designing autonomous unmanned networks consisting of a large number of heterogeneous nodes that may be configured in ad-hoc fashions and incorporating intricate architectures. In fact, one of the challenges in this field is to recognize the entire network as a heterogenous collection of physical and information systems with complicated interconnections and interactions. Using high data rates that are essential for real-time interactive command and control systems, these networks require utilization of optimal integration of local feedback loops into a scheduling and resource allocation systems. This integration becomes particularly problematic in presence of latencies and delays. Given that dynamics of a network of unmanned systems could easily become unstable depending on interconnections among nodes, in this paper stability of the resulting time-delayed controlled network based on configuration changes is studied. We also formally investigate sufficient conditions for our proposed robust resource allocation strategies to be able to cope with these interconnections and time-delays in an optimal fashion. Our time-delayed dependent network consists of three nodes that can be configured into different architectures. To model our traffic and network we use a fluid flow model that is of low order and simpler than a detailed Markovian queueing probabilistic model. Using sliding mode-based variable structure control (SM-VSC) techniques that enjoy robustness capabilities, we design on the basis of an inaccurate/uncertain model our proposed robust nonlinear feedback-based control approaches. The results presented are analyzed analytically to guarantee stability of known/unknown time-delayed dependent network of unmanned systems for different configurations.

  18. Resource allocation in heterogeneous cloud radio access networks: advances and challenges

    KAUST Repository

    Dahrouj, Hayssam

    2015-06-01

    Base station densification is increasingly used by network operators to provide better throughput and coverage performance to mobile subscribers in dense data traffic areas. Such densification is progressively diffusing the move from traditional macrocell base stations toward heterogeneous networks with diverse cell sizes (e.g., microcell, picocell, femotcell) and diverse radio access technologies (e.g., GSM, CDMA), and LTE). The coexistence of the different network entities brings an additional set of challenges, particularly in terms of the provisioning of high-speed communications and the management of wireless interference. Resource sharing between different entities, largely incompatible in conventional systems due to the lack of interconnections, becomes a necessity. By connecting all the base stations from different tiers to a central processor (referred to as the cloud) through wire/wireline backhaul links, the heterogeneous cloud radio access network, H-CRAN, provides an open, simple, controllable, and flexible paradigm for resource allocation. This article discusses challenges and recent developments in H-CRAN design. It proposes promising resource allocation schemes in H-CRAN: coordinated scheduling, hybrid backhauling, and multicloud association. Simulations results show how the proposed strategies provide appreciable performance improvement compared to methods from recent literature. © 2015 IEEE.

  19. Users’ classification-based call admission control with adaptive resource reservation for LTE-A networks

    Directory of Open Access Journals (Sweden)

    Salman Ali AlQahtani

    2017-01-01

    In this paper, we introduce the user’s privileges and traffic maximum delay tolerance as additional dimensions in the call admission control processes to efficiently control the utilization of LTE-A network resources. Based on this idea, we propose an efficient call admission control scheme named “delay aware and user categorizing-based CAC with adaptive resource reservation (DA–UC-ARR”, where the user priority is adjusted dynamically based on the current network conditions and the users’ categorizations and traffic delay tolerances, to increase the network’s resource utilization and at the same time to maximize the operators’ revenue. In this proposed scheme, the users are classified into Golden users and Silver users, and the type of service per user is classified as real time (RT and non-real time (NRT services. We compare the performance of the proposed scheme with the corresponding results of previous schemes, referred to as the adaptive resource reservation-based call admission control (ARR-CAC (Andrews et al., 2010; AlQahtani, 2014, where user categorization and delay were not taken into consideration in the call admission control process. Simulation results indicate the superiority of the proposed scheme because it is able to achieve a better balance between system utilization, users’ privileges provided by network operators and QoS provisioning compared to the ARR-CAC scheme.

  20. Tree spatial structure, host composition and resource availability influence mirid density or black pod prevalence in cacao agroforests in Cameroon.

    Science.gov (United States)

    Gidoin, Cynthia; Babin, Régis; Bagny Beilhe, Leïla; Cilas, Christian; ten Hoopen, Gerben Martijn; Bieng, Marie Ange Ngo

    2014-01-01

    Combining crop plants with other plant species in agro-ecosystems is one way to enhance ecological pest and disease regulation mechanisms. Resource availability and microclimatic variation mechanisms affect processes related to pest and pathogen life cycles. These mechanisms are supported both by empirical research and by epidemiological models, yet their relative importance in a real complex agro-ecosystem is still not known. Our aim was thus to assess the independent effects and the relative importance of different variables related to resource availability and microclimatic variation that explain pest and disease occurrence at the plot scale in real complex agro-ecosystems. The study was conducted in cacao (Theobroma cacao) agroforests in Cameroon, where cocoa production is mainly impacted by the mirid bug, Sahlbergella singularis, and black pod disease, caused by Phytophthora megakarya. Vegetation composition and spatial structure, resource availability and pest and disease occurrence were characterized in 20 real agroforest plots. Hierarchical partitioning was used to identify the causal variables that explain mirid density and black pod prevalence. The results of this study show that cacao agroforests can be differentiated on the basis of vegetation composition and spatial structure. This original approach revealed that mirid density decreased when a minimum number of randomly distributed forest trees were present compared with the aggregated distribution of forest trees, or when forest tree density was low. Moreover, a decrease in mirid density was also related to decreased availability of sensitive tissue, independently of the effect of forest tree structure. Contrary to expectations, black pod prevalence decreased with increasing cacao tree abundance. By revealing the effects of vegetation composition and spatial structure on mirids and black pod, this study opens new perspectives for the joint agro-ecological management of cacao pests and diseases at the

  1. Tree Spatial Structure, Host Composition and Resource Availability Influence Mirid Density or Black Pod Prevalence in Cacao Agroforests in Cameroon

    Science.gov (United States)

    Gidoin, Cynthia; Babin, Régis; Bagny Beilhe, Leïla; Cilas, Christian; ten Hoopen, Gerben Martijn; Bieng, Marie Ange Ngo

    2014-01-01

    Combining crop plants with other plant species in agro-ecosystems is one way to enhance ecological pest and disease regulation mechanisms. Resource availability and microclimatic variation mechanisms affect processes related to pest and pathogen life cycles. These mechanisms are supported both by empirical research and by epidemiological models, yet their relative importance in a real complex agro-ecosystem is still not known. Our aim was thus to assess the independent effects and the relative importance of different variables related to resource availability and microclimatic variation that explain pest and disease occurrence at the plot scale in real complex agro-ecosystems. The study was conducted in cacao (Theobroma cacao) agroforests in Cameroon, where cocoa production is mainly impacted by the mirid bug, Sahlbergella singularis, and black pod disease, caused by Phytophthora megakarya. Vegetation composition and spatial structure, resource availability and pest and disease occurrence were characterized in 20 real agroforest plots. Hierarchical partitioning was used to identify the causal variables that explain mirid density and black pod prevalence. The results of this study show that cacao agroforests can be differentiated on the basis of vegetation composition and spatial structure. This original approach revealed that mirid density decreased when a minimum number of randomly distributed forest trees were present compared with the aggregated distribution of forest trees, or when forest tree density was low. Moreover, a decrease in mirid density was also related to decreased availability of sensitive tissue, independently of the effect of forest tree structure. Contrary to expectations, black pod prevalence decreased with increasing cacao tree abundance. By revealing the effects of vegetation composition and spatial structure on mirids and black pod, this study opens new perspectives for the joint agro-ecological management of cacao pests and diseases at the

  2. Virtualized ANR to Manage Resources for Optimization of Neighbour Cell Lists in 5G Mobile Wireless Networks

    Directory of Open Access Journals (Sweden)

    Yoonsu Shin

    2017-01-01

    Full Text Available In future, more devices such as wearable devices will be connected to the networks. This will increase simultaneous handovers. The coverage of a cell will be small because a superhigh frequency used in 5G wireless networks does not propagate very far. This trend will increase the number of neighbour cell lists and it will accelerate the change of neighbour cell lists since the coverage of cells can be altered by the environment. Meanwhile, the ANR technology will be essential in 5G networks. Since the network environment in the future is not similar to the present, the strategy of ANR should also be different from the present. First, since practical neighbour cell lists in each cell are changed frequently and individually, it is necessary to optimize them frequently and individually. Second, since the neighbour cell lists in each cell are not changed similarly, it is necessary to operate ANR flexibly. To respond to these issues, we propose to use network function virtualization (NFV for ANR. To evaluate the proposed strategies, we measured additional resource consumption and the latency of handover if neighbour cell lists are not optimized when UEs perform handover simultaneously. These experiments are conducted using Amarisoft LTE-100 Platform.

  3. Resource Allocation in a Frequency Hopping PCS1900/GSM/DCS1800 Type of Network

    DEFF Research Database (Denmark)

    Nielsen, Thomas Toftegaard; Wigard, Jeroen; Michaelsen, Per-Henrik

    1999-01-01

    Resource allocation in a frequency hopping network is even more problematic than in a traditional network. The combined effect from all serving frequencies has to be considered directly in the allocation process. An algorithm doing this for a PCS1900/GSM/DCS1800 type of network is presented...

  4. Influence of Resource Availability on the Foraging Strategies of the Triangle Butterflyfish Chaetodon triangulum in the Maldives.

    Directory of Open Access Journals (Sweden)

    Josie F Chandler

    Full Text Available Obligate coral feeders such as many members of the Chaetodontidae family (also known as butterflyfish often show strong preferences for particular coral species. This is thought to have evolved through natural selection as an energy-maximising strategy. Although some species remain as highly specialised feeders throughout their lifetime, many corallivores show a degree of dietary versatility when food abundance is limited; a strategy described by the optimal foraging theory. This study aimed to examine if, within-reef differences in the feeding regime and territory size of the Triangle Butterflyfish Chaetodon triangulum occurred, as a function of resource availability. Results showed that the dietary specialisation of C. triangulum was significant in both areas of low and high coral cover (χL22 = 2.52 x 102, P<0.001 and χL22 = 3.78 x 102, P<0.001 respectively. Resource selection functions (RSFs, calculated for the two main sites of contrasting coral assemblage, showed that in the resource-rich environments, only two Genera (Acropora and Pocillopora were preferentially selected for, with the majority of other corals being actively 'avoided'. Conversely, in territories of lower coral coverage, C. triangulum was being less selective in its prey choice and consuming corals in a more even distribution with respect to their availability. Interestingly, coral cover appeared to show no significant effect on feeding rate, however it was a primary determinant of territory size. The findings of the study agree with the predictions of the optimal foraging theory, in that where food supply is scarce, dietary specialisation is minimised and territory size increased. This results in maximising energy intake. This study represents the first scientific evidence that C. triangulum is an obligate corallivore and, as with many other butterflyfish, is therefore dependent on healthy scleractinian corals for survival.

  5. Integrated information systems; protection, substation control, network management - Available solutions on the market

    Energy Technology Data Exchange (ETDEWEB)

    Oedmansson, E.; Oehlen, C. [ABB TNP International, Vaesteraas, (Sweden)

    1995-11-01

    Many utilities sees the use of Information Technology as a main tool to meet requirements of improved cost efficiency of their transmission and distribution networks. They need to reduce both investments and operational costs. One of the possibilities is the vertical integration of Protection, Substation Control and Network management as well as the necessary communication links. This paper describes the evolution of the new technology and how this today offers new solutions for `The Intelligent Power System`. 6 refs, 4 figs

  6. Self-Similarity Superresolution for Resource-Constrained Image Sensor Node in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Yuehai Wang

    2014-01-01

    Full Text Available Wireless sensor networks, in combination with image sensors, open up a grand sensing application field. It is a challenging problem to recover a high resolution (HR image from its low resolution (LR counterpart, especially for low-cost resource-constrained image sensors with limited resolution. Sparse representation-based techniques have been developed recently and increasingly to solve this ill-posed inverse problem. Most of these solutions are based on an external dictionary learned from huge image gallery, consequently needing tremendous iteration and long time to match. In this paper, we explore the self-similarity inside the image itself, and propose a new combined self-similarity superresolution (SR solution, with low computation cost and high recover performance. In the self-similarity image super resolution model (SSIR, a small size sparse dictionary is learned from the image itself by the methods such as KSVD. The most similar patch is searched and specially combined during the sparse regulation iteration. Detailed information, such as edge sharpness, is preserved more faithfully and clearly. Experiment results confirm the effectiveness and efficiency of this double self-learning method in the image super resolution.

  7. A NOVEL RESOURCE CONSTRAINT SECURE(RCS ROUTING PROTOCOL FOR WIRELESS SENSOR NETWORK

    Directory of Open Access Journals (Sweden)

    R. GEETHA

    2017-02-01

    Full Text Available Geographic routing protocols are the most preferred routing protocols for Wireless Sensor Networks (WSN since they rely on geographic position information. Hence we propose geography based Resource Constraint Secure routing (RCS protocol. The existing routing protocol named Cost Aware SEcure Routing (CASER allows messages to be transmitted using random walking routing strategy. In the Random walking method, there is a chance of choosing low energy node as a relay node. RCS protocol overcomes this by transmitting the data via energy aware route only and it provides authentication by using Modified ElGammal Signature (MES scheme on Elliptic curve algorithm. For security purposes, the content of each message can also be encrypted by using a symmetric key encryption technique and decoded at the sink node by knowing the same secret key used by the source. So, unauthenticated person cannot access the original data. Therefore the protocol ensures a secure message delivery option to maximize the message delivery ratio under adversarial attacks. The performance evaluation results show that RCS performs better than CASER with respect to Packet Delivery Ratio, Energy Balance Factor and End-to-End Delay, Throughput and Routing overhead.

  8. Dynamic Resource Management in MC-CDMA Based Cellular Wireless Networks

    Directory of Open Access Journals (Sweden)

    Bala Jeevitha Vani

    2009-10-01

    Full Text Available Most of the multimedia and Internet services today are asymmetric in nature, and require high data rate support. Allocating equal band width in both uplink and downlink is not prudent solution, as most of the time user requirement is more either in uplink or downlink. The Multi Carrier Code Division Multiple Access (MC-CDMA system with time division duplex mode can easily met this requirement by dynamically declaring traffic direction in TDD slot, and adaptively allocating the sub channels. In this paper, we propose a adaptive slot and sub carrier allocation algorithm, that can be independently implemented in each cell of mobile communication network. Our analytical model is generalization of two cell concept to represent a multi cell model. Based on two cell concept four cases of interference pattern has been considered and simulated separately in presence of Additive White Gaussian Noise (AWGN and Rayleigh Channel. The simulated result suggests the requirement of approximately 9dB of Signal to Noise Ratio (SNR to maintain Bit Error Rate below 10-3. We also analyze the average delay incurred by the proposed algorithm in allocating resources.

  9. The SOL Genomics Network. A Comparative Resource for Solanaceae Biology and Beyond1

    Science.gov (United States)

    Mueller, Lukas A.; Solow, Teri H.; Taylor, Nicolas; Skwarecki, Beth; Buels, Robert; Binns, John; Lin, Chenwei; Wright, Mark H.; Ahrens, Robert; Wang, Ying; Herbst, Evan V.; Keyder, Emil R.; Menda, Naama; Zamir, Dani; Tanksley, Steven D.

    2005-01-01

    The SOL Genomics Network (SGN; http://sgn.cornell.edu) is a rapidly evolving comparative resource for the plants of the Solanaceae family, which includes important crop and model plants such as potato (Solanum tuberosum), eggplant (Solanum melongena), pepper (Capsicum annuum), and tomato (Solanum lycopersicum). The aim of SGN is to relate these species to one another using a comparative genomics approach and to tie them to the other dicots through the fully sequenced genome of Arabidopsis (Arabidopsis thaliana). SGN currently houses map and marker data for Solanaceae species, a large expressed sequence tag collection with computationally derived unigene sets, an extensive database of phenotypic information for a mutagenized tomato population, and associated tools such as real-time quantitative trait loci. Recently, the International Solanaceae Project (SOL) was formed as an umbrella organization for Solanaceae research in over 30 countries to address important questions in plant biology. The first cornerstone of the SOL project is the sequencing of the entire euchromatic portion of the tomato genome. SGN is collaborating with other bioinformatics centers in building the bioinformatics infrastructure for the tomato sequencing project and implementing the bioinformatics strategy of the larger SOL project. The overarching goal of SGN is to make information available in an intuitive comparative format, thereby facilitating a systems approach to investigations into the basis of adaptation and phenotypic diversity in the Solanaceae family, other species in the Asterid clade such as coffee (Coffea arabica), Rubiaciae, and beyond. PMID:16010005

  10. USING ANALYTIC NETWORK FOR SELECTION OF ENTERPRISE RESOURCE PLANNING (ERP ALIGNED TO BUSINESS STRATEGY

    Directory of Open Access Journals (Sweden)

    Alberto de Medeiros Junior

    2014-10-01

    Full Text Available The choice of an Enterprise Resource Planning (ERP must be made judiciously by the high costs involved in the acquisition of such systems. Managers in areas such as accounting, financial and information technology need support and tools that help in selecting an appropriate ERP for their business. With this article, we present a study aimed at investigating the possibility of a Decision Support System (DSS to be used for this selection interrelating evaluation criteria, which could allow to contemplate the strategic alignment between Business and Information Technology. From the literature review 28 factors related to the selection of software packages, with special emphasis on ERP were identified. For the research procedures, the qualitative ones were adopted, in that the 18 factors considered relevant to a good selection of ERP were classified with the Delphi technique and used as input in a DSS: Analytical Network Process (ANP, applied as a Case Study in a small business that hired the ERP. The results showed that the ANP was efficient in interrelated criteria and evaluated the strategic alignment between Business and Information Technology.

  11. Integration of available regenerative energy sources in community networks for both electricity and heating

    Energy Technology Data Exchange (ETDEWEB)

    Alcalde Melo, Henrique

    2013-03-06

    . Water can be heated up to 70 C at least once a week preventing the bacterium Legionella to grow. The community is able to supply 99% of the uncontrollable load group demand and 97% of the controllable load group demand. There is enough energy available to heat space during the cold months, if heat pumps with a coefficient of performance greater than two are used. The electric vehicles can be charged using the energy generated in the community via grid or extra battery banks. If energy prices continue to increase, German households will try to find solutions to reduce their energy bills. The integration of several households forming a community network is a solution that optimizes the energy use and space (especially taking wind turbines in consideration), and reduces investments. However, the implementation of such a community still depends on the availability of space, improvement and price reduction of energy storage systems, regulations for energy exchange as well as willingness of the people living in such a community to adapt their daily routine according to the availability of energy.

  12. Effects of resource availability and propagule supply on native species recruitment in sagebrush ecosystems invaded by Bromus tectorum

    Science.gov (United States)

    Mazzola, Monica B.; Chambers, Jeanne C.; Blank, Robert R.; Pyke, David A.; Schupp, Eugene W.; Allcock, Kimberly G.; Doescher, Paul S.; Nowak, Robert S.

    2011-01-01

    Resource availability and propagule supply are major factors influencing establishment and persistence of both native and invasive species. Increased soil nitrogen (N) availability and high propagule inputs contribute to the ability of annual invasive grasses to dominate disturbed ecosystems. Nitrogen reduction through carbon (C) additions can potentially immobilize soil N and reduce the competitiveness of annual invasive grasses. Native perennial species are more tolerant of resource limiting conditions and may benefit if N reduction decreases the competitive advantage of annual invaders and if sufficient propagules are available for their establishment. Bromus tectorum, an exotic annual grass in the sagebrush steppe of western North America, is rapidly displacing native plant species and causing widespread changes in ecosystem processes. We tested whether nitrogen reduction would negatively affect B. tectorum while creating an opportunity for establishment of native perennial species. A C source, sucrose, was added to the soil, and then plots were seeded with different densities of both B. tectorum (0, 150, 300, 600, and 1,200 viable seeds m-2) and native species (0, 150, 300, and 600 viable seeds m-2). Adding sucrose had short-term (1 year) negative effects on available nitrogen and B. tectorum density, biomass and seed numbers, but did not increase establishment of native species. Increasing propagule availability increased both B. tectorum and native species establishment. Effects of B. tectorum on native species were density dependent and native establishment increased as B. tectorum propagule availability decreased. Survival of native seedlings was low indicating that recruitment is governed by the seedling stage.

  13. Access Point Backhaul Resource Aggregation as a Many-to-One Matching Game in Wireless Local Area Networks

    Directory of Open Access Journals (Sweden)

    Kawther Hassine

    2017-01-01

    Full Text Available This paper studies backhaul bandwidth aggregation in the context of a wireless local area network composed of two different types of access points: those with spare backhaul capacity (which we term providers and those in shortage of it (beneficiaries; the aim is to transfer excess capacity from providers to beneficiaries. We model the system as a matching game with many-to-one setting wherein several providers can be matched to one beneficiary and adopt the so-called deferred acceptance algorithm to reach an optimal and stable solution. We consider two flavors, when the beneficiaries are limited in their resource demands and when they are not, and two scenarios, when resources are abundant and when they are scarce. Our results show that the many-to-one setting outperforms the one-to-one case in terms of overall throughput gain, resource usage, and individual beneficiaries satisfaction by up to 50%, whether resources are scarce or abundant. As of the limited versus nonlimited case, the former ensures more fair sharing of spectral resources and higher satisfaction percentage between beneficiaries.

  14. Opportunistic Capacity-Based Resource Allocation for Chunk-Based Multi-Carrier Cognitive Radio Sensor Networks.

    Science.gov (United States)

    Huang, Jie; Zeng, Xiaoping; Jian, Xin; Tan, Xiaoheng; Zhang, Qi

    2017-01-18

    The spectrum allocation for cognitive radio sensor networks (CRSNs) has received considerable research attention under the assumption that the spectrum environment is static. However, in practice, the spectrum environment varies over time due to primary user/secondary user (PU/SU) activity and mobility, resulting in time-varied spectrum resources. This paper studies resource allocation for chunk-based multi-carrier CRSNs with time-varied spectrum resources. We present a novel opportunistic capacity model through a continuous time semi-Markov chain (CTSMC) to describe the time-varied spectrum resources of chunks and, based on this, a joint power and chunk allocation model by considering the opportunistically available capacity of chunks is proposed. To reduce the computational complexity, we split this model into two sub-problems and solve them via the Lagrangian dual method. Simulation results illustrate that the proposed opportunistic capacity-based resource allocation algorithm can achieve better performance compared with traditional algorithms when the spectrum environment is time-varied.

  15. NETWORK MEDIA RESOURCES AS THE INSTRUMENT OF RECRUITING OF FOREIGN STUDENTS IN THE RUSSIAN HIGHER EDUCATION INSTITUTIONS

    Directory of Open Access Journals (Sweden)

    Гульнара Амангельдиновна Краснова

    2017-12-01

    Full Text Available Information technologies become more and more important instrument of recruiting of foreign students. In article the online recruiting methods used by foreign and Russian higher education institutions now and recent trends in the field of education export are considered. Results of the research “Education Value” conducted in 2015 by HSBC bank are given. Are discussed a role of the websites for students, parents, the recruiting agencies in information search and social networks as one of the main channels of recruiting of students. Social aspects of Wikipedia as important information resource and instrument of recruiting of foreign students are discussed.

  16. Agents, Individuals, and Networks: Modeling Methods to Inform Natural Resource Management in Regional Landscapes

    Directory of Open Access Journals (Sweden)

    Lael Parrott

    2012-09-01

    Full Text Available Landscapes are complex systems. Landscape dynamics are the result of multiple interacting biophysical and socioeconomic processes that are linked across a broad range of spatial, temporal, and organizational scales. Understanding and describing landscape dynamics poses enormous challenges and demands the use of new multiscale approaches to modeling. In this synthesis article, we present three regional systems - i.e., a forest system, a marine system, and an agricultural system - and describe how hybrid, bottom-up modeling of these systems can be used to represent linkages across scales and between subsystems. Through the use of these three examples, we describe how modeling can be used to simulate emergent system responses to different conservation policy and management scenarios from the bottom up, thereby increasing our understanding of important drivers and feedback loops within a landscape. The first case study involves the use of an individual-based modeling approach to simulate the effects of forest harvesting on the movement patterns of large mammals in Canada's boreal forest and the resulting emergent population dynamics. This model is being used to inform forest harvesting and management guidelines. The second case study combines individual and agent-based approaches to simulate the dynamics of individual boats and whales in a marine park. This model is being used to inform decision-makers on how to mitigate the impacts of maritime traffic on whales in the Saint Lawrence Estuary in eastern Canada. The third example is a case study of biodiversity conservation efforts on the Eyre Peninsula, South Australia. In this example, the social-ecological system is represented as a complex network of interacting components. Methods of network analysis can be used to explore the emergent responses of the system to changes in the network structure or configuration, thus informing managers about the resilience of the system. These three examples

  17. Nearly Optimal Resource Allocation for Downlink OFDMA in 2-D Cellular Networks

    CERN Document Server

    Ksairi, Nassar; Ciblat, Philippe

    2010-01-01

    In this paper, we propose a resource allocation algorithm for the downlink of sectorized two-dimensional (2-D) OFDMA cellular networks assuming statistical Channel State Information (CSI) and fractional frequency reuse. The proposed algorithm can be implemented in a distributed fashion without the need to any central controlling units. Its performance is analyzed assuming fast fading Rayleigh channels and Gaussian distributed multicell interference. We show that the transmit power of this simple algorithm tends, as the number of users grows to infinity, to the same limit as the minimal power required to satisfy all users' rate requirements i.e., the proposed resource allocation algorithm is asymptotically optimal. As a byproduct of this asymptotic analysis, we characterize a relevant value of the reuse factor that only depends on an average state of the network.

  18. Game theoretic wireless resource allocation for H.264 MGS video transmission over cognitive radio networks

    Science.gov (United States)

    Fragkoulis, Alexandros; Kondi, Lisimachos P.; Parsopoulos, Konstantinos E.

    2015-03-01

    We propose a method for the fair and efficient allocation of wireless resources over a cognitive radio system network to transmit multiple scalable video streams to multiple users. The method exploits the dynamic architecture of the Scalable Video Coding extension of the H.264 standard, along with the diversity that OFDMA networks provide. We use a game-theoretic Nash Bargaining Solution (NBS) framework to ensure that each user receives the minimum video quality requirements, while maintaining fairness over the cognitive radio system. An optimization problem is formulated, where the objective is the maximization of the Nash product while minimizing the waste of resources. The problem is solved by using a Swarm Intelligence optimizer, namely Particle Swarm Optimization. Due to the high dimensionality of the problem, we also introduce a dimension-reduction technique. Our experimental results demonstrate the fairness imposed by the employed NBS framework.

  19. Biometric Methods for Secure Communications in Body Sensor Networks: Resource-Efficient Key Management and Signal-Level Data Scrambling

    Directory of Open Access Journals (Sweden)

    Dimitrios Hatzinakos

    2008-03-01

    Full Text Available As electronic communications become more prevalent, mobile and universal, the threats of data compromises also accordingly loom larger. In the context of a body sensor network (BSN, which permits pervasive monitoring of potentially sensitive medical data, security and privacy concerns are particularly important. It is a challenge to implement traditional security infrastructures in these types of lightweight networks since they are by design limited in both computational and communication resources. A key enabling technology for secure communications in BSN's has emerged to be biometrics. In this work, we present two complementary approaches which exploit physiological signals to address security issues: (1 a resource-efficient key management system for generating and distributing cryptographic keys to constituent sensors in a BSN; (2 a novel data scrambling method, based on interpolation and random sampling, that is envisioned as a potential alternative to conventional symmetric encryption algorithms for certain types of data. The former targets the resource constraints in BSN's, while the latter addresses the fuzzy variability of biometric signals, which has largely precluded the direct application of conventional encryption. Using electrocardiogram (ECG signals as biometrics, the resulting computer simulations demonstrate the feasibility and efficacy of these methods for delivering secure communications in BSN's.

  20. Relevance Epistasis Network of Gastritis for Intra-chromosomes in the Korea Associated Resource (KARE Cohort Study

    Directory of Open Access Journals (Sweden)

    Hyun-hwan Jeong

    2014-12-01

    Full Text Available Gastritis is a common but a serious disease with a potential risk of developing carcinoma. Helicobacter pylori infection is reported as the most common cause of gastritis, but other genetic and genomic factors exist, especially single-nucleotide polymorphisms (SNPs. Association studies between SNPs and gastritis disease are important, but results on epistatic interactions from multiple SNPs are rarely found in previous genome-wide association (GWA studies. In this study, we performed computational GWA case-control studies for gastritis in Korea Associated Resource (KARE data. By transforming the resulting SNP epistasis network into a gene-gene epistasis network, we also identified potential gene-gene interaction factors that affect the susceptibility to gastritis.

  1. Implementation of an Optical-Wireless Network with Spectrum Sensing and Dynamic Resource Allocation Using Optically Controlled Reconfigurable Antennas

    Directory of Open Access Journals (Sweden)

    E. Raimundo-Neto

    2014-01-01

    Full Text Available This work proposes the concept and reports the implementation of an adaptive and cognitive radio over fiber architecture. It is aimed at dealing with the new demands for convergent networks by means of simultaneously providing the functionalities of multiband radiofrequency spectrum sensing, dynamic resource allocation, and centralized processing capability, as well as the use of optically controlled reconfigurable antennas and radio over fiber technology. The performance of this novel and innovative architecture has been evaluated in a geographically distributed optical-wireless network under real conditions and for different fiber lengths. Experimental results demonstrate reach extension of more than 40 times and an enhancement of more than 30 dB in the carrier to interference plus noise ratio parameter.

  2. Investigation of dynamic resource allocation based on transmission performance analysis and service classification in wavelength-division-multiplexing optical networks

    Science.gov (United States)

    Tang, Yong; Sun, Xiaohan; Rao, Min; Li, Lei; Wang, Chen; Zhang, Mingde

    2002-11-01

    In wavelength-routed optical networks, the transmission performance of the optical lightpaths available may not always satisfy the service requirements due to the quality degradation of signals induced by crosstalk, polarized mode dispersion (PMD), nonlinear effects, etc. Based on the integrated consideration of signal transmission impairments and service classification, a novel model on dynamic resource allocation in optical networks is presented in this paper. The model classifies the service requirements with different priorities and provides differentiated QoS in the optical domain. By adopting a multi-path RWA algorithm, called DMC-OVWP, the lightpath candidates are found out for each connection request of the services. Afterwards, by analyzing the transmission qualities of the lightpath candidates, an appropriate lightpath matched the request priority are picked out and set up.

  3. Opportunistic diet of Triportheus nematurus (Characiformes: Triportheidae in Southern Pantanal ponds: influences of temporal availability and abundance of resources

    Directory of Open Access Journals (Sweden)

    Douglas Alves Lopes

    2017-11-01

    Full Text Available The aim of this study was to investigate the diet composition and feeding strategies of Triportheus nematurus at the Miranda-Abobral floodplain region and evaluate if the temporal phenomenon of the flood pulse has influenced in the diet composition of the species. The fishes were sampled quarterly – between August/2014 and July/2016 – in the marginal ponds located in the Estrada Parque (MS 184. The feeding habits of T. nematurus was characterized as omnivorous and its opportunistic feeding behaviour, since its diet is composed of different resources along of the year. Insects and organic matter were the most important items during the drought period; plant material (leaves and roots and Euglenophyceae algae were more expressive during the inundation period; insects and fruits were also abundant during the flood period. Through statistical analysis, it was possible to verify significant variation in the diet composition of the species. This variation in the components of the diet may be related to the availability of resources in the ponds throughout the year and reflect an already known pattern in Neotropical fish populations, which present high alimentary plasticity.

  4. Nest establishment, pollination efficiency, and reproductive success of Megachile rotundata (Hymenoptera: Megachilidae) in relation to resource availability in field enclosures.

    Science.gov (United States)

    Pitts-Singer, Theresa L; Bosch, Jordi

    2010-02-01

    The alfalfa leafcutting bee, Megachile rotundata (Fabricius), is used to pollinate alfalfa, Medicago sativa L., for seed production in the United States and Canada. It is difficult to reliably sustain commercial M. rotundata populations in the United States because of problems with disease, parasites, predators, and unexplained mortality. One possible explanation for early immature mortality is that, relative to floral availability, superfluous numbers of bees are released in alfalfa fields where resources quickly become limited. Our objective was to determine how M. rotundata density affects bee nesting, pollination efficiency, and reproductive success. Various numbers of bees were released into enclosures on an alfalfa field, but only 10-90% of released female bees established nests. Therefore, a "bee density index" was derived for each enclosure from the number of established females and number of open flowers over time. As the density index increased, significant reductions occurred in the number of pollinated flowers, number of nests, and number of cells produced per bee, as well as the percentage of cells that produced viable prepupae by summer's end and the percentage that produced adult bees. The percentage of cells resulting in early brood mortality (i.e., pollen balls) significantly increased as the density index increased. We conclude that bee nest establishment, pollination efficiency, and reproductive success are compromised when bee densities are high relative to floral resource availability. Open field studies are needed to determine commercial bee densities that result in sustainable bee populations and adequate pollination for profitable alfalfa seed production.

  5. 77 FR 49016 - Notice of Availability of Record of Decision for the Pocatello Field Office Resource Management...

    Science.gov (United States)

    2012-08-15

    ... Resource Management Plan/Environmental Impact Statement AGENCY: Bureau of Land Management, Interior. ACTION... Record of Decision (ROD)/Approved Resource Management Plan (RMP) for the Pocatello Field Office located... RMP addresses management of resources and resource uses on approximately 618,300 acres of public land...

  6. Cross stratum resources protection in fog-computing-based radio over fiber networks for 5G services

    Science.gov (United States)

    Guo, Shaoyong; Shao, Sujie; Wang, Yao; Yang, Hui

    2017-09-01

    In order to meet the requirement of internet of things (IoT) and 5G, the cloud radio access network is a paradigm which converges all base stations computational resources into a cloud baseband unit (BBU) pool, while the distributed radio frequency signals are collected by remote radio head (RRH). A precondition for centralized processing in the BBU pool is an interconnection fronthaul network with high capacity and low delay. However, it has become more complex and frequent in the interaction between RRH and BBU and resource scheduling among BBUs in cloud. Cloud radio over fiber network has been proposed in our previous work already. In order to overcome the complexity and latency, in this paper, we first present a novel cross stratum resources protection (CSRP) architecture in fog-computing-based radio over fiber networks (F-RoFN) for 5G services. Additionally, a cross stratum protection (CSP) scheme considering the network survivability is introduced in the proposed architecture. The CSRP with CSP scheme can effectively pull the remote processing resource locally to implement the cooperative radio resource management, enhance the responsiveness and resilience to the dynamic end-to-end 5G service demands, and globally optimize optical network, wireless and fog resources. The feasibility and efficiency of the proposed architecture with CSP scheme are verified on our software defined networking testbed in terms of service latency, transmission success rate, resource occupation rate and blocking probability.

  7. Resource Allocation for OFDMA-Based Cognitive Radio Networks with Application to H.264 Scalable Video Transmission

    Directory of Open Access Journals (Sweden)

    Coon JustinP

    2011-01-01

    Full Text Available Resource allocation schemes for orthogonal frequency division multiple access- (OFDMA- based cognitive radio (CR networks that impose minimum and maximum rate constraints are considered. To demonstrate the practical application of such systems, we consider the transmission of scalable video sequences. An integer programming (IP formulation of the problem is presented, which provides the optimal solution when solved using common discrete programming methods. Due to the computational complexity involved in such an approach and its unsuitability for dynamic cognitive radio environments, we propose to use the method of lift-and-project to obtain a stronger formulation for the resource allocation problem such that the integrality gap between the integer program and its linear relaxation is reduced. A simple branching operation is then performed that eliminates any noninteger values at the output of the linear program solvers. Simulation results demonstrate that this simple technique results in solutions very close to the optimum.

  8. Distributed Optimal Dispatch of Distributed Energy Resources Over Lossy Communication Networks

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Junfeng; Yang, Tao; Wu, Di; Kalsi, Karanjit; Johansson, Karl Henrik

    2017-11-01

    In this paper, we consider the economic dispatch problem (EDP), where a cost function that is assumed to be strictly convex is assigned to each of distributed energy resources (DERs), over packet dropping networks. The goal of a standard EDP is to minimize the total generation cost while meeting total demand and satisfying individual generator output limit. We propose a distributed algorithm for solving the EDP over networks. The proposed algorithm is resilient against packet drops over communication links. Under the assumption that the underlying communication network is strongly connected with a positive probability and the packet drops are independent and identically distributed (i.i.d.), we show that the proposed algorithm is able to solve the EDP. Numerical simulation results are used to validate and illustrate the main results of the paper.

  9. Competition between cheatgrass and bluebunch wheatgrass is altered by temperature, resource availability, and atmospheric CO2 concentration.

    Science.gov (United States)

    Larson, Christian D; Lehnhoff, Erik A; Noffsinger, Chance; Rew, Lisa J

    2017-12-22

    Global change drivers (elevated atmospheric CO2, rising surface temperatures, and changes in resource availability) have significant consequences for global plant communities. In the northern sagebrush steppe of North America, the invasive annual grass Bromus tectorum (cheatgrass) is expected to benefit from projected warmer and drier conditions, as well as increased CO2 and nutrient availability. In growth chambers, we addressed this expectation using two replacement series experiments designed to test competition between B. tectorum and the native perennial bunchgrass Pseudoroegneria spicata. In the first experiment, we tested the effects of elevated temperature, decreased water and increased nutrient availability, on competition between the two species. In the second, we tested the effects of elevated atmospheric CO2 and decreased water availability on the competitive dynamic. In both experiments, under all conditions, P. spicata suppressed B. tectorum, though, in experiment one, warmer and drier conditions and elevated nutrient availability increased B. tectorum's competitiveness. In experiment two, when grown in monoculture, both species responded positively to elevated CO2. However, when grown in competition, elevated CO2 increased P. spicata's suppressive effect, and the combination of dry soil conditions and elevated CO2 enhanced this effect. Our findings demonstrate that B. tectorum competitiveness with P. spicata responds differently to global change drivers; thus, future conditions are unlikely to facilitate B. tectorum invasion into established P. spicata communities of the northern sagebrush steppe. However, disturbance (e.g., fire) to these communities, and the associated increase in soil nutrients, elevates the risk of B. tectorum invasion.

  10. Market Model for Resource Allocation in Emerging Sensor Networks with Reinforcement Learning.

    Science.gov (United States)

    Zhang, Yue; Song, Bin; Zhang, Ying; Du, Xiaojiang; Guizani, Mohsen

    2016-11-29

    Emerging sensor networks (ESNs) are an inevitable trend with the development of the Internet of Things (IoT), and intend to connect almost every intelligent device. Therefore, it is critical to study resource allocation in such an environment, due to the concern of efficiency, especially when resources are limited. By viewing ESNs as multi-agent environments, we model them with an agent-based modelling (ABM) method and deal with resource allocation problems with market models, after describing users' patterns. Reinforcement learning methods are introduced to estimate users' patterns and verify the outcomes in our market models. Experimental results show the efficiency of our methods, which are also capable of guiding topology management.

  11. Artificial Neural Network Prediction of Chemical-Disease Relationships using Readily Available Chemical Properties

    Science.gov (United States)

    2014-03-27

    solubility and permeability in drug discovery and development settings. Advanced Drug Delivery Reviews, 64, Supplement(0), 4-17. doi:10.1016/j.addr...2013). EPA/NSF Networks for Characterizing Chemical Lifecycle. Arlington, Virginia, U.S.A. Nguyen, T., Malley, R., Inkelis , S., & Kuppermann, N

  12. Evaluating primary care research networks: a review of currently available tools

    NARCIS (Netherlands)

    Bleeker, M.C.G.; Stalman, W.A.B.; van der Horst, H.E.

    2010-01-01

    Background: An increasing number of primary care research networks (PCRNs) are being developed around the world. Despite the fact that they have existed for a long time in some countries, little is known about what they have actually achieved. There is an ongoing debate in the literature about the

  13. Simulating Water Resource Availability under Data Scarcity—A Case Study for the Ferghana Valley (Central Asia

    Directory of Open Access Journals (Sweden)

    Iuliia Radchenko

    2014-10-01

    Full Text Available Glaciers and snowmelt supply the Naryn and Karadarya rivers, and about 70% of the water available for the irrigated agriculture in the Ferghana Valley. Nineteen smaller catchments contribute the remaining water mainly from annual precipitation. The latter will gain importance if glaciers retreat as predicted. Hydrological models can visualize such climate change impacts on water resources. However, poor data availability often hampers simulating the contributions of smaller catchments. We tested several data pre-processing methods (gap filling, MODAWEC (MOnthly to DAily WEather Converter, lapse rate and their effect on the performance of the HBV (Hydrologiska Byråns Vattenavdelning-light model. Monte Carlo simulations were used to define parameter uncertainties and ensembles of behavioral model runs. Model performances were evaluated by constrained measures of goodness-of-fit criteria (cumulative bias, coefficient of determination, model efficiency coefficients (NSE for high flow and log-transformed flow. The developed data pre-processing arrangement can utilize data of relatively poor quality (only monthly means or daily data with gaps but still provide model results with NSE between 0.50 and 0.88. Some of these may not be accurate enough to directly guide water management applications. However, the pre-processing supports producing key information that may initiate rigging of monitoring facilities, and enable water management to respond to fundamentally changing water availability.

  14. Genetic diversity and genomic resources available for the small millet crops to accelerate a New Green Revolution.

    Science.gov (United States)

    Goron, Travis L; Raizada, Manish N

    2015-01-01

    Small millets are nutrient-rich food sources traditionally grown and consumed by subsistence farmers in Asia and Africa. They include finger millet (Eleusine coracana), foxtail millet (Setaria italica), kodo millet (Paspalum scrobiculatum), proso millet (Panicum miliaceum), barnyard millet (Echinochloa spp.), and little millet (Panicum sumatrense). Local farmers value the small millets for their nutritional and health benefits, tolerance to extreme stress including drought, and ability to grow under low nutrient input conditions, ideal in an era of climate change and steadily depleting natural resources. Little scientific attention has been paid to these crops, hence they have been termed "orphan cereals." Despite this challenge, an advantageous quality of the small millets is that they continue to be grown in remote regions of the world which has preserved their biodiversity, providing breeders with unique alleles for crop improvement. The purpose of this review, first, is to highlight the diverse traits of each small millet species that are valued by farmers and consumers which hold potential for selection, improvement or mechanistic study. For each species, the germplasm, genetic and genomic resources available will then be described as potential tools to exploit this biodiversity. The review will conclude with noting current trends and gaps in the literature and make recommendations on how to better preserve and utilize diversity within these species to accelerate a New Green Revolution for subsistence farmers in Asia and Africa.

  15. Réserves, ressources et disponibilités mondiales en hydrocarbures World Hydrocarbon Reserves, Resources and Availabilities

    Directory of Open Access Journals (Sweden)

    Bois C.

    2006-11-01

    Full Text Available Les réserves prouvées en hydrocarbures conventionnels s'élèvent dans le monde à 90 milliards de tonnes de pétrole et 78 000 milliards de m3 de gaz, ce qui représente respectivement 30 et 50 ans au taux actuel de production. Les réserves et ressources supplémentaires à découvrir peuvent être considérées comme 2,3 à 2,4 plus importantes mais ces valeurs sont entachées d'une forte incertitude. II existe de grandes ressources en hydrocarbures non conventionnels, mais elles sont coûteuses à mettre en oeuvre et demandent surtout des investissements considérables. On peut prévoir que la production mondiale de pétrole atteindra son maximum vers 1990. Proven reserves of conventional hydrocarbons in the world amount to 90 billion tons of oil and 78 000 billion cubic meters of gas, respectively representing 30 and 50 years of supply at the present rate of production. Further reserves and resources yet to be discovered may be considered to be 2. 3 to 2. 4 times greater, but there is a high degree of uncertainty in these figures. Extensive resources of unconventional hydrocarbons exist, but they are costly to implement and, above all, require considerable investments. World petroleum production can be predicted to reach its maximum around 1990.

  16. Quality resource networks for young women in science: The role of Internet-facilitated ties

    Science.gov (United States)

    Gillette, Shana Cecile

    In communications, a new approach to the study of online interaction has been suggested by social network analysts. Garton, Haythornthwaite, and Wellman (1997) have outlined the importance of using network analysis to study how media are interconnected with other social aspects of a media user's world. As applied here, this approach to communication when combined with recent network studies from the fields of education and rural development, provides a method for looking at the role of Internet-facilitated ties in the development of resource networks in the learning communities of young women from seven rural schools across the state of Washington. Twenty-six young women (ages 14-16) from diverse cultural and ethnic backgrounds (approximately half of the participants are Hispanic or Native American, the other half are White) participated in the research. Participants were selected because they shared a common educational orientation through Rural Girls in Science, a NSF-funded program at the Northwest Center for Research on Women at the University of Washington. As part of the school-based component of the Rural Girls in Science program, all 26 participants designed and conducted year-long, community-based research projects in science. Each school in the program was provided an Internet workstation for communication and research. Through the Internet, students could conceivably maintain distant ties with mentors and research scientists whom they met at summer camp as well as seek additional information resources. Toward the conclusion of the long-term research projects, each student participant was interviewed using a participatory form of network analysis that included a combined qualitative and quantitative approach. Given the small number of participants and schools in the sample, the results from the analysis can not be generalized to a larger population. However the study of the structure and composition of networks among individuals and school groups provided

  17. Transportation Energy Futures Series: Alternative Fuel Infrastructure Expansion: Costs, Resources, Production Capacity, and Retail Availability for Low-Carbon Scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Melaina, W. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Heath, Garvin [National Renewable Energy Lab. (NREL), Golden, CO (United States); Sandor, Debra [National Renewable Energy Lab. (NREL), Golden, CO (United States); Steward, Darlene [National Renewable Energy Lab. (NREL), Golden, CO (United States); Vimmerstedt, Laura [National Renewable Energy Lab. (NREL), Golden, CO (United States); Warner, Ethan [National Renewable Energy Lab. (NREL), Golden, CO (United States); Webster, Karen W. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2013-04-01

    The petroleum-based transportation fuel system is complex and highly developed, in contrast to the nascent low-petroleum, low-carbon alternative fuel system. This report examines how expansion of the low-carbon transportation fuel infrastructure could contribute to deep reductions in petroleum use and greenhouse gas (GHG) emissions across the U.S. transportation sector. Three low-carbon scenarios, each using a different combination of low-carbon fuels, were developed to explore infrastructure expansion trends consistent with a study goal of reducing transportation sector GHG emissions to 80% less than 2005 levels by 2050.These scenarios were compared to a business-as-usual (BAU) scenario and were evaluated with respect to four criteria: fuel cost estimates, resource availability, fuel production capacity expansion, and retail infrastructure expansion.

  18. 78 FR 21965 - Notice of Availability of the Draft Tri-County Resource Management Plan and Draft Environmental...

    Science.gov (United States)

    2013-04-12

    ... Rd. NE., Albuquerque, NM; the Socorro BLM Field Office at 901 South Highway 85, Socorro, NM; the... acreage.) This ACEC would be managed for scenic, cultural, and ecological resource values. Proposed... managed for ecological and cultural resource values. Proposed resource-use limitations include: Exclusion...

  19. 78 FR 50088 - Notice of Availability of the Northwest Colorado Greater Sage-Grouse Draft Resource Management...

    Science.gov (United States)

    2013-08-16

    ... Resource Management Plan Amendment and Draft Environmental Impact Statement for the Northwest Colorado... Colorado Greater Sage-Grouse Draft Resource Management Plan (RMP) Amendment and Draft Environmental Impact... White River field offices, as well as the Land and Resource Management Plan (LRMP) for the Routt...

  20. The Effect of Land Use on Availability of Japanese Freshwater Resources and Its Significance for Water Footprinting

    Directory of Open Access Journals (Sweden)

    Masaharu Motoshita

    2016-01-01

    Full Text Available All relevant effects on water must be assessed in water footprinting for identifying hotspots and managing the impacts of products, processes, and services throughout the life cycle. Although several studies have focused on physical water scarcity and degradation of water quality, the relevance of land use in water footprinting has not been widely addressed. Here, we aimed to verify the extent of land-use effect in the context of water footprinting. Intensity factors of land use regarding the loss of freshwater availability are modeled by calculating water balance at grid scale in Japan. A water footprint inventory and impacts related to land use are assessed by applying the developed intensity factors and comparing them with those related to water consumption and degradation. Artificial land use such as urban area results in the loss of many parts of available freshwater input by precipitation. When considering water footprint inventory, the dominance of land use is less than that of water consumption. However, the effect of land use is relevant to the assessment of water footprint impact by differentiating stress on water resources. The exclusion of land use effect underestimates the water footprint of goods produced in Japan by an average of around 37%.

  1. Cross-Layer Resource Scheduling for Video Traffic in the Downlink of OFDMA-Based Wireless 4G Networks

    Directory of Open Access Journals (Sweden)

    2009-03-01

    Full Text Available Designing scheduling algorithms at the medium access control (MAC layer relies on a variety of parameters including quality of service (QoS requirements, resource allocation mechanisms, and link qualities from the corresponding layers. In this paper, we present an efficient cross-layer scheduling scheme, namely, Adaptive Token Bank Fair Queuing (ATBFQ algorithm, which is designed for packet scheduling and resource allocation in the downlink of OFDMA-based wireless 4G networks. This algorithm focuses on the mechanisms of efficiency and fairness in multiuser frequency-selective fading environments. We propose an adaptive method for ATBFQ parameter selection which integrates packet scheduling with resource mapping. The performance of the proposed scheme is compared to that of the round-robin (RR and the score-based (SB schedulers. It is observed from simulation results that the proposed scheme with adaptive parameter selection provides enhanced performance in terms of queuing delay, packet dropping rate, and cell-edge user performance, while the total sector throughput remains comparable. We further analyze and compare achieved fairness of the schemes in terms of different fairness indices available in literature.

  2. Disturbance promotes non-indigenous bacterial invasion in soil microcosms: analysis of the roles of resource availability and community structure.

    Directory of Open Access Journals (Sweden)

    Manqiang Liu

    Full Text Available BACKGROUND: Invasion-biology is largely based on non-experimental observation of larger organisms. Here, we apply an experimental approach to the subject. By using microbial-based microcosm-experiments, invasion-biology can be placed on firmer experimental, and hence, less anecdotal ground. A better understanding of the mechanisms that govern invasion-success of bacteria in soil communities will provide knowledge on the factors that hinder successful establishment of bacteria artificially inoculated into soil, e.g. for remediation purposes. Further, it will yield valuable information on general principles of invasion biology in other domains of life. METHODOLOGY/PRINCIPAL FINDINGS: Here, we studied invasion and establishment success of GFP-tagged Pseudomonas fluorescens DSM 50090 in laboratory microcosms during a 42-day period. We used soil heating to create a disturbance gradient, and hypothesized that increased disturbance would facilitate invasion; our experiments confirmed this hypothesis. We suggest that the key factors associated with the heating disturbance that explain the enhanced invasion success are increased carbon substrate availability and reduced diversity, and thus, competition- and predation-release. In a second experiment we therefore separated the effects of increased carbon availability and decreased diversity. Here, we demonstrated that the effect of the indigenous soil community on bacterial invasion was stronger than that of resource availability. In particular, introduced bacteria established better in a long term perspective at lower diversity and predation pressure. CONCLUSION: We propose increased use of microbial systems, for experimental study of invasion scenarios. They offer a simple and cost-efficient way to study and understand biological invasion. Consequently such systems can help us to better predict the mechanisms controlling changes in stability of communities and ecosystems. This is becoming increasingly

  3. Influence of Resource Availability on the Foraging Strategies of the Triangle Butterflyfish Chaetodon triangulum in the Maldives.

    Science.gov (United States)

    Chandler, Josie F; Burn, Deborah; Berggren, Per; Sweet, Michael J

    2016-01-01

    Obligate coral feeders such as many members of the Chaetodontidae family (also known as butterflyfish) often show strong preferences for particular coral species. This is thought to have evolved through natural selection as an energy-maximising strategy. Although some species remain as highly specialised feeders throughout their lifetime, many corallivores show a degree of dietary versatility when food abundance is limited; a strategy described by the optimal foraging theory. This study aimed to examine if, within-reef differences in the feeding regime and territory size of the Triangle Butterflyfish Chaetodon triangulum occurred, as a function of resource availability. Results showed that the dietary specialisation of C. triangulum was significant in both areas of low and high coral cover (χL22 = 2.52 x 102, Pchoice and consuming corals in a more even distribution with respect to their availability. Interestingly, coral cover appeared to show no significant effect on feeding rate, however it was a primary determinant of territory size. The findings of the study agree with the predictions of the optimal foraging theory, in that where food supply is scarce, dietary specialisation is minimised and territory size increased. This results in maximising energy intake. This study represents the first scientific evidence that C. triangulum is an obligate corallivore and, as with many other butterflyfish, is therefore dependent on healthy scleractinian corals for survival.

  4. Experimental demonstration of multi-dimensional resources integration for service provisioning in cloud radio over fiber network

    Science.gov (United States)

    Yang, Hui; Zhang, Jie; Ji, Yuefeng; He, Yongqi; Lee, Young

    2016-07-01

    Cloud radio access network (C-RAN) becomes a promising scenario to accommodate high-performance services with ubiquitous user coverage and real-time cloud computing in 5G area. However, the radio network, optical network and processing unit cloud have been decoupled from each other, so that their resources are controlled independently. Traditional architecture cannot implement the resource optimization and scheduling for the high-level service guarantee due to the communication obstacle among them with the growing number of mobile internet users. In this paper, we report a study on multi-dimensional resources integration (MDRI) for service provisioning in cloud radio over fiber network (C-RoFN). A resources integrated provisioning (RIP) scheme using an auxiliary graph is introduced based on the proposed architecture. The MDRI can enhance the responsiveness to dynamic end-to-end user demands and globally optimize radio frequency, optical network and processing resources effectively to maximize radio coverage. The feasibility of the proposed architecture is experimentally verified on OpenFlow-based enhanced SDN testbed. The performance of RIP scheme under heavy traffic load scenario is also quantitatively evaluated to demonstrate the efficiency of the proposal based on MDRI architecture in terms of resource utilization, path blocking probability, network cost and path provisioning latency, compared with other provisioning schemes.

  5. Identifying barriers to the availability and use of Magnesium Sulphate Injection in resource poor countries: A case study in Zambia

    Directory of Open Access Journals (Sweden)

    Hill Suzanne R

    2010-12-01

    Full Text Available Abstract Background Pre-eclampsia and eclampsia are serious complications of pregnancy and major causes of maternal mortality and morbidity worldwide. According to systematic reviews and WHO guidelines magnesium sulphate injection (MgSO4 should be the first -line treatment for severe pre-eclampsia and eclampsia. Studies have shown that this safe and effective medicine is unavailable and underutilized in many resource poor countries. The objective of this study was to identify barriers to the availability and use of MgSO4 in the Zambian Public Health System. Methods A 'fishbone' (Ishikawa diagram listing probable facilitators to the availability and use of MgSO4 identified from the literature was used to develop an assessment tool. Barriers to availability and use of MgSO4 were assessed at the regulatory/government, supply, procurement, distribution, health facility and health professional levels. The assessment was completed during August 2008 using archival data, and observations at a pragmatic sample of health facilities providing obstetric services in Lusaka District, Zambia. Results The major barrier to the availability of MgSO4 within the public health system in Zambia was lack of procurement by the Ministry of Health. Other barriers identified included a lack of demand by health professionals at the health centre level and a lack of in-service training in the use of MgSO4. Where there was demand by obstetricians, magnesium sulphate injection was being procured from the private sector by the hospital pharmacy despite not being registered and licensed for use for the treatment of severe pre-eclampsia and eclampsia by the national Pharmaceutical Regulatory Authority. Conclusions The case study in Zambia highlights the complexities that underlie making essential medicines available and used appropriately. The fishbone diagram is a useful theoretical framework for illustrating the complexity of translating research findings into clinical

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

    DEFF Research Database (Denmark)

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

    2015-01-01

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

  7. The science, technology and research network (STARNET) a searchable thematic compilation of web resources

    Science.gov (United States)

    Blados, W.R.; Cotter, G.A.; Hermann, T.

    2007-01-01

    International alliances in space efforts have resulted in a more rapid diffusion of space technology. This, in turn, increases pressure on organizations to push forward with technological developments and to take steps to maximize their inclusion into the research and development (R&D) process and the overall advancement and enhancement of space technology. To cope with this vast and rapidly growing amount of data and information that is vital to the success of the innovation, the Information Management Committee (IMC) of the Research Technology Agency (RTA) developed the science, technology and research network (STARNET). The purpose of this network is to facilitate access to worldwide information elements in terms of science, technology and overall research. It provides a virtual library with special emphasis on international security; a "one stop" information resource for policy makers, program managers, scientists, engineers, researchers and others. ?? 2007 IEEE.

  8. On the Dual-Decomposition-Based Resource and Power Allocation with Sleeping Strategy for Heterogeneous Networks

    KAUST Repository

    Alsharoa, Ahmad M.

    2015-05-01

    In this paper, the problem of radio and power resource management in long term evolution heterogeneous networks (LTE HetNets) is investigated. The goal is to minimize the total power consumption of the network while satisfying the user quality of service determined by each target data rate. We study the model where one macrocell base station is placed in the cell center, and multiple small cell base stations and femtocell access points are distributed around it. The dual decomposition technique is adopted to jointly optimize the power and carrier allocation in the downlink direction in addition to the selection of turned off small cell base stations. Our numerical results investigate the performance of the proposed scheme versus different system parameters and show an important saving in terms of total power consumption. © 2015 IEEE.

  9. Effects on Learners' Performance of Using Selected and Open Network Resources in a Problem-Based Learning Activity

    Science.gov (United States)

    Hsu, Ching-Kun; Hwang, Gwo-Jen; Chuang, Chien-Wen; Chang, Chih-Kai

    2012-01-01

    Owing to the popularity of computers and computer networks, fostering the web-based problem-solving ability of students has become an important educational objective in recent years. This study attempted to compare the effects of using selected and open network resources on students' intentions with regard to their information system usage by…

  10. Adaptive call admission control and resource allocation in multi server wireless/cellular network

    Science.gov (United States)

    Jain, Madhu; Mittal, Ragini

    2016-11-01

    The ever increasing demand of the subscribers has put pressure on the capacity of wireless networks around the world. To utilize the scare resources, in the present paper we propose an optimal allocation scheme for an integrated wireless/cellular model with handoff priority and handoff guarantee services. The suggested algorithm optimally allocates the resources in each cell and dynamically adjust threshold to control the admission. To give the priority to handoff calls over the new calls, the provision of guard channels and subrating scheme is taken into consideration. The handoff voice call may balk and renege from the system while waiting in the buffer. An iterative algorithm is implemented to generate the arrival rate of the handoff calls in each cell. Various performance indices are established in term of steady state probabilities. The sensitivity analysis has also been carried out to examine the tractability of algorithms and to explore the effects of system descriptors on the performance indices.

  11. Software cost/resource modeling: Deep space network software cost estimation model

    Science.gov (United States)

    Tausworthe, R. J.

    1980-01-01

    A parametric software cost estimation model prepared for JPL deep space network (DSN) data systems implementation tasks is presented. The resource estimation model incorporates principles and data from a number of existing models, such as those of the General Research Corporation, Doty Associates, IBM (Walston-Felix), Rome Air Force Development Center, University of Maryland, and Rayleigh-Norden-Putnam. The model calibrates task magnitude and difficulty, development environment, and software technology effects through prompted responses to a set of approximately 50 questions. Parameters in the model are adjusted to fit JPL software lifecycle statistics. The estimation model output scales a standard DSN work breakdown structure skeleton, which is then input to a PERT/CPM system, producing a detailed schedule and resource budget for the project being planned.

  12. Integration of 100% Micro-Distributed Energy Resources in the Low Voltage Distribution Network

    DEFF Research Database (Denmark)

    You, Shi; Segerberg, Helena

    2014-01-01

    The existing electricity infrastructure may to a great extent limit a high penetration of the micro-sized Distributed Energy Resources (DERs), due to the physical bottlenecks, e.g. thermal capacitates of cables, transformers and the voltage limitations. In this study, the integration impacts...... of heat pumps (HPs) and plug-in electric vehicles (PEVs) at 100% penetration level on a representative urban residential low voltage (LV) distribution network of Denmark are investigated by performing a steady-state load flow analysis through an integrated simulation setup. Three DERs integration...

  13. Relay selection and resource allocation for two-way DF-AF cognitive radio networks

    KAUST Repository

    Alsharoa, Ahmad M.

    2013-08-01

    In this letter, the problem of relay selection and optimal resource allocation for two-way relaying cognitive radio networks using half duplex amplify-and-forward and decode-and-forward protocols is investigated. The primary and secondary users are assumed to access the spectrum simultaneously, in a way that the interference introduced to the primary users should be below a certain tolerated limit. Dual decomposition and subgradient methods are used to find the optimal power allocation. A suboptimal approach based on a genetic algorithm is also presented. Simulation results show that the proposed suboptimal algorithm offers a performance close to the optimal performance with a considerable complexity saving. © 2013 IEEE.

  14. Modelling Framework and the Quantitative Analysis of Distributed Energy Resources in Future Distribution Networks

    DEFF Research Database (Denmark)

    Han, Xue; Sandels, Claes; Zhu, Kun

    2013-01-01

    , comprising distributed generation, active demand and electric vehicles. Subsequently, quantitative analysis was made on the basis of the current and envisioned DER deployment scenarios proposed for Sweden. Simulations are performed in two typical distribution network models for four seasons. The simulation......There has been a large body of statements claiming that the large-scale deployment of Distributed Energy Resources (DERs) could eventually reshape the future distribution grid operation in numerous ways. Thus, it is necessary to introduce a framework to measure to what extent the power system...

  15. Bringing Global Climate Modeling Data Into the Classroom: Effective Pedagogy With Available Resources and Possibilities for the Future

    Science.gov (United States)

    Shellito, C. J.

    2005-12-01

    Climate modeling results can be an excellent tool for promoting inquiry into the dynamics of past, present, and future climates. Exposing students to global climate model (GCM) output early on in their exploration of the climate system offers them the potential to apply new knowledge to a growing understanding of climate theory in the context of model results. While there have been thousands of climate modeling experiments, very little model output is available in an easily accessible format for review by the general public. Much data is in a format that is difficult to access and requires sufficient technical skill for processing. There are a few sources of GCM output available online that may be directly utilized in the classroom. Effectively using this output in the classroom can require some preparation, however, as students need direction and context that is generally not provided on these websites. In this presentation, I review the sources of GCM output presently available online, and make suggestions for incorporating these model results into classroom lessons at the college undergraduate level. Ultimately, with some modification in presentation format and accessibility, GCM output could become an effective educational resource at all educational levels. Additionally, making GCM output more accessible to the general public offers the potential to increase awareness of global climate and environmental change, as well as enhance cross-disciplinary collaboration between the physical and social sciences. This presentation will include suggestions regarding how research and education communities might cooperate to develop effective tools for accessing processed model output, and how we might continue to develop the use of model output to promote scientific learning through inquiry.

  16. An Authentication and Key Management Mechanism for Resource Constrained Devices in IEEE 802.11-based IoT Access Networks

    Directory of Open Access Journals (Sweden)

    Ki-Wook Kim

    2017-09-01

    Full Text Available Many Internet of Things (IoT services utilize an IoT access network to connect small devices with remote servers. They can share an access network with standard communication technology, such as IEEE 802.11ah. However, an authentication and key management (AKM mechanism for resource constrained IoT devices using IEEE 802.11ah has not been proposed as yet. We therefore propose a new AKM mechanism for an IoT access network, which is based on IEEE 802.11 key management with the IEEE 802.1X authentication mechanism. The proposed AKM mechanism does not require any pre-configured security information between the access network domain and the IoT service domain. It considers the resource constraints of IoT devices, allowing IoT devices to delegate the burden of AKM processes to a powerful agent. The agent has sufficient power to support various authentication methods for the access point, and it performs cryptographic functions for the IoT devices. Performance analysis shows that the proposed mechanism greatly reduces computation costs, network costs, and memory usage of the resource-constrained IoT device as compared to the existing IEEE 802.11 Key Management with the IEEE 802.1X authentication mechanism.

  17. Environmental impacts caused by the uncontrolled human activities on water resources availability in the Niger Inland Delta

    Science.gov (United States)

    Moussa, Ibrahim; Oyerinde, Ganiyu; Some, Corentin; Abdou, Ali; Mariko, Adama; Wisser, Dominik

    2014-05-01

    The Niger River basin is a significant source of water and food for West Africa. As an agricultural region, the basin is highly dependent on the water availability that is currently under pressure from increased demand with rising populations and climate variability and change. The Niger Inland Delta is one of the largest flood plains (about 40.000skm) in Africa and serves a number of interlinked human activities, such as irrigation, fishing, livestock, and reservoirs. Future changes in the dynamics of river flow may change the inundation dynamics of the delta and impact these activities. At the same time, the population in the basin is likely to double in the next 30 years, putting additional pressure on the Delta's water resources and land use. Most hydrological models do not adequately represent these dynamics of the Inland Delta. Here we present an overview of the hydrological processes that occur over the Niger inland delta. We used digital elevation model and satellite images to analyze the spatio-temporal variations in relation to observed river flow. Based on this analysis, we have developed a representation of these processes fore hydrological models for the basin. The basic analysis of in situ discharges confirms the impact of the inner delta area on the discharge of the main river, characterized by a strong reduction of about 15% to 50% as a result of evaporation and water abstractions for irrigation.

  18. Summary of hydrologic modeling for the Delaware River Basin using the Water Availability Tool for Environmental Resources (WATER)

    Science.gov (United States)

    Williamson, Tanja N.; Lant, Jeremiah G.; Claggett, Peter; Nystrom, Elizabeth A.; Milly, Paul C.D.; Nelson, Hugh L.; Hoffman, Scott A.; Colarullo, Susan J.; Fischer, Jeffrey M.

    2015-11-18

    The Water Availability Tool for Environmental Resources (WATER) is a decision support system for the nontidal part of the Delaware River Basin that provides a consistent and objective method of simulating streamflow under historical, forecasted, and managed conditions. In order to quantify the uncertainty associated with these simulations, however, streamflow and the associated hydroclimatic variables of potential evapotranspiration, actual evapotranspiration, and snow accumulation and snowmelt must be simulated and compared to long-term, daily observations from sites. This report details model development and optimization, statistical evaluation of simulations for 57 basins ranging from 2 to 930 km2 and 11.0 to 99.5 percent forested cover, and how this statistical evaluation of daily streamflow relates to simulating environmental changes and management decisions that are best examined at monthly time steps normalized over multiple decades. The decision support system provides a database of historical spatial and climatic data for simulating streamflow for 2001–11, in addition to land-cover and general circulation model forecasts that focus on 2030 and 2060. WATER integrates geospatial sampling of landscape characteristics, including topographic and soil properties, with a regionally calibrated hillslope-hydrology model, an impervious-surface model, and hydroclimatic models that were parameterized by using three hydrologic response units: forested, agricultural, and developed land cover. This integration enables the regional hydrologic modeling approach used in WATER without requiring site-specific optimization or those stationary conditions inferred when using a statistical model.

  19. The geographical distribution of plantation forests and land resources potentially available for pine plantations in the U.S. South

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Daowei [Forest Economics and Policy, School of Forestry and Wildlife Sciences, Auburn University, Auburn, Alabama 36849-5418 (United States); Polyakov, Maksym [Centre for Environmental Economics and Policy, University of Western Australia, M089, 35 Stirling Hwy, Crawley WA 6009 (Australia)

    2010-12-15

    In this paper, we provide an assessment of plantation forests and private land resources potentially available for pine plantation development in 11 southern states of the United States. After a sustained growth for 50 years, plantation forests (softwood and hardwood on both private and public lands) amounted to 18 million ha or 24 percent of all timberlands in these states in 2007. The vast majority of the plantation forests were established on private lands with fast-growing loblolly pines and slash pines. While purposeful hardwood plantations were rare, there were hardwood stands growing on failed pine plantation sites. Using a two-stage Markov land use transition model, we forecast that private forest land in these states will decline about 7 percent or from 66 million ha in 1997 to 61 million ha in 2027, primarily due to urbanization, and that private pine plantations will rise nearly 40 percent from 11 million ha to 16 million ha. Further, growth in pine plantations will decline in coming decades, and states with low population and population growth have the greatest increase in plantations. These plantations, along with other woody biomass, are expected to play an important role in the emerging bio-energy sector. (author)

  20. The Impact of Resource Scarcity on Bonding and Bridging Social Capital: the Case of Fishers' Information-Sharing Networks in Loreto, BCS, Mexico

    Directory of Open Access Journals (Sweden)

    Saudiel Ramirez-Sanchez

    2009-06-01

    Full Text Available Fishers often rely on their social capital to cope with resource fluctuations by sharing information on the abundance and location of fish. Drawing on research in seven coastal fishing communities in Loreto, Baja California Sur, Mexico, we examine the effect of resource scarcity on the bonding, bridging, and linking social-capital patterns of fishers' information-sharing networks. We found that: (1 fishers' information sharing is activated in response to varying ecological conditions; (2 resource scarcity is an ambiguous indicator of the extent to which fishers share information on the abundance and location of fish within and between communities; (3 information sharing is based on trust and occurs through kinship, friendship, and acquaintance social relations; (4 friendship ties play a key and flexible role in fishers' social networks within and between communities; (5 overall, the composition of fishers' social networks follows a friendship>kinship>acquaintance order of importance; and (6 the function of social ties, internal conflict, and settlement histories moderate the effects of resource scarcity on fishers' social capital. We conclude by arguing that the livelihoods of fishers from Loreto have adaptive capacity for dealing with fish fluctuations but little or no proactive resilience to address resource-management issues.

  1. Availability of mineral resources for society; Disponibilidad y retos actuales de los recursos minerales para la sociedad

    Energy Technology Data Exchange (ETDEWEB)

    Price, J. G.; Espi, J. A.

    2014-06-01

    Trends in global mineral production and expanding uses of mineral resources foretell a bright future, although with significant challenges, for exploration and development. Demand for mineral resources is likely to remain high and grow to meet increases in world population and standards of living. Significant challenges include meeting future demand with new discoveries and developing the resources in environmentally, socially, and economically sustainable ways. A historical perspective from the last 50 years on finding new mineral districts, discovering new types of ore deposits, and using new technologies in exploration suggests that the world will not run out of mineral resources. It is likely that substitution and recycling will play increasingly major roles in meeting global mineral demand. New technologies for ocean mining will help add to the resource base. Historical perspectives also suggest that mining scams will continue, and environmental, health, and safety concerns will be major factors in deciding where future mines will be located and how they will be operated. (Author)

  2. Exponential Arithmetic Based Self-Healing Group Key Distribution Scheme with Backward Secrecy under the Resource-Constrained Wireless Networks.

    Science.gov (United States)

    Guo, Hua; Zheng, Yandong; Zhang, Xiyong; Li, Zhoujun

    2016-04-28

    In resource-constrained wireless networks, resources such as storage space and communication bandwidth are limited. To guarantee secure communication in resource-constrained wireless networks, group keys should be distributed to users. The self-healing group key distribution (SGKD) scheme is a promising cryptographic tool, which can be used to distribute and update the group key for the secure group communication over unreliable wireless networks. Among all known SGKD schemes, exponential arithmetic based SGKD (E-SGKD) schemes reduce the storage overhead to constant, thus is suitable for the the resource-constrained wireless networks. In this paper, we provide a new mechanism to achieve E-SGKD schemes with backward secrecy. We first propose a basic E-SGKD scheme based on a known polynomial-based SGKD, where it has optimal storage overhead while having no backward secrecy. To obtain the backward secrecy and reduce the communication overhead, we introduce a novel approach for message broadcasting and self-healing. Compared with other E-SGKD schemes, our new E-SGKD scheme has the optimal storage overhead, high communication efficiency and satisfactory security. The simulation results in Zigbee-based networks show that the proposed scheme is suitable for the resource-restrained wireless networks. Finally, we show the application of our proposed scheme.

  3. Performance analysis of differentiated resource-sharing in a wireless ad-hoc network

    NARCIS (Netherlands)

    Roijers, F.; van den Berg, H.; Mandjes, M.

    2010-01-01

    In this paper we model and analyze a relay node in a wireless ad-hoc network; the capacity available at this node is used to both transmit traffic from the source nodes (towards the relay node), and to serve traffic at the relay node (so that it can be forwarded to successor nodes). Clearly, a

  4. Performance evaluation of multi-stratum resources optimization with network functions virtualization for cloud-based radio over optical fiber networks.

    Science.gov (United States)

    Yang, Hui; He, Yongqi; Zhang, Jie; Ji, Yuefeng; Bai, Wei; Lee, Young

    2016-04-18

    Cloud radio access network (C-RAN) has become a promising scenario to accommodate high-performance services with ubiquitous user coverage and real-time cloud computing using cloud BBUs. In our previous work, we implemented cross stratum optimization of optical network and application stratums resources that allows to accommodate the services in optical networks. In view of this, this study extends to consider the multiple dimensional resources optimization of radio, optical and BBU processing in 5G age. We propose a novel multi-stratum resources optimization (MSRO) architecture with network functions virtualization for cloud-based radio over optical fiber networks (C-RoFN) using software defined control. A global evaluation scheme (GES) for MSRO in C-RoFN is introduced based on the proposed architecture. The MSRO can enhance the responsiveness to dynamic end-to-end user demands and globally optimize radio frequency, optical and BBU resources effectively to maximize radio coverage. The efficiency and feasibility of the proposed architecture are experimentally demonstrated on OpenFlow-based enhanced SDN testbed. The performance of GES under heavy traffic load scenario is also quantitatively evaluated based on MSRO architecture in terms of resource occupation rate and path provisioning latency, compared with other provisioning scheme.

  5. Projecting impacts of climate change on water availability using artificial neural network techniques

    Science.gov (United States)

    Swain, Eric D.; Gomez-Fragoso, Julieta; Torres-Gonzalez, Sigfredo

    2017-01-01

    Lago Loíza reservoir in east-central Puerto Rico is one of the primary sources of public water supply for the San Juan metropolitan area. To evaluate and predict the Lago Loíza water budget, an artificial neural network (ANN) technique is trained to predict river inflows. A method is developed to combine ANN-predicted daily flows with ANN-predicted 30-day cumulative flows to improve flow estimates. The ANN application trains well for representing 2007–2012 and the drier 1994–1997 periods. Rainfall data downscaled from global circulation model (GCM) simulations are used to predict 2050–2055 conditions. Evapotranspiration is estimated with the Hargreaves equation using minimum and maximum air temperatures from the downscaled GCM data. These simulated 2050–2055 river flows are input to a water budget formulation for the Lago Loíza reservoir for comparison with 2007–2012. The ANN scenarios require far less computational effort than a numerical model application, yet produce results with sufficient accuracy to evaluate and compare hydrologic scenarios. This hydrologic tool will be useful for future evaluations of the Lago Loíza reservoir and water supply to the San Juan metropolitan area.

  6. Service Class Resource Management For Green Wireless-Optical Broadband Access NetworksWOBAN

    Directory of Open Access Journals (Sweden)

    SRUTHY.S

    2015-08-01

    Full Text Available Abstract-Broadband access networks have become an essential part of worldwide communication systems because of the exponential growth of broadband services such as video on demand high definition TV internet protocol TV and video conferencing. Exponential growth in the volume of wireless data boosted by the growing popularity of mobile devices such as smartphone and tablets has forced the telecommunication industries to rethink the way networks are currently designed and to focus on the development of high-capacity mobile broadband networks. In response to this challenge researchers have been working toward the development of an integrated wireless optical broadband access network. Two major candidate technologies which are currently known for their high capacity as well as quality of service QoS for multimedia traffic are passive optical networks PON and fourth generation 4G wireless networks. PON is a wired access technology well known for its cost efficiency and high capacity whereas 4G is a wireless broadband access technology which has achieved broad market acceptance because of its ease of deployment ability to offer mobility and its cost efficiency. Integration of PON and 4G technologies in the form of wireless-optical broadband access networks offers advantages such as extension of networks in rural areas support for mobile broadband services and quick deployment of broadband networks. These two technologies however have different design architectures for handling broadband services that require quality of service. For example 4G networks use traffic classification for supporting different QoS demands whereas the PON architecture has no such mechanism to differentiate between types of traffic. These two technologies also differ in their power saving mechanisms. Propose a service class mapping for the integrated PON-4G network which is based on the MG1 queuing model and class-based power saving mechanism which significantly improves the

  7. Cross-layer design for radio resource allocation based on priority scheduling in OFDMA wireless access network

    Directory of Open Access Journals (Sweden)

    Chen Yen-Wen

    2011-01-01

    Full Text Available Abstract The orthogonal frequency-division multiple access (OFDMA system has the advantages of flexible subcarrier allocation and adaptive modulation with respect to channel conditions. However, transmission overhead is required in each frame to broadcast the arrangement of radio resources to all mobile stations within the coverage of the same base station. This overhead greatly affects the utilization of valuable radio resources. In this paper, a cross layer scheme is proposed to reduce the number of traffic bursts at the downlink of an OFDMA wireless access network so that the overhead of the media access protocol (MAP field can be minimized. The proposed scheme considers the priorities and the channel conditions of quality of service (QoS traffic streams to arrange for them to be sent with minimum bursts in a heuristic manner. In addition, the trade-off between the degradation of the modulation level and the reduction of traffic bursts is investigated. Simulation results show that the proposed scheme can effectively reduce the traffic bursts and, therefore, increase resource utilization.

  8. Evaluation of water resources monitoring networks: study applied to surface waters in the Macaé River Basin

    Directory of Open Access Journals (Sweden)

    Carolina Cloris Lopes Benassuly

    2012-04-01

    Full Text Available Knowledge of hydrological phenomena is required in water resources monitoring, in order to structure the water management, focusing on ensuring its multiple uses while allowing that resource´s control and conservation. The effectiveness of monitoring depends on adequate information systems design and proper operation conditions. Data acquisition, treatment and analysis are vital for establishing management strategies, thus monitoring systems and networks shall be conceived according to their main objectives, and be optimized in terms of location of data stations. The generated data shall also model hydrological behavior of the studied basin, so that data interpolation can be applied to the whole basin. The present work aimed to join concepts and methods that guide the structuring of hydrologic monitoring networks of surface waters. For evaluating historical series characteristics as well as work stations redundancy, the entropy method was used. The Macaé River Basin’s importance is related to the public and industrial uses of water in the region that is responsible for more than 80% of Brazilian oil and gas production, what justifies the relevance of the research made. This study concluded that despite of its relatively short extension, the Macaé River Basin should have higher monitoring network density, in order to provide more reliable management data. It also depicted the high relevancy of stations located in its upper course.

  9. Maximizing Weapon System Availability With a Multi-Echelon Supply Network

    Science.gov (United States)

    2014-06-01

    that system availability is maximized. This thesis develops a stochastic optimization model that prescribes optimal investments in spare parts for... stochastic optimization to maximize the expected number of time periods a weapon system is 2 available for use. The key decisions in our model ...stationary demands over time. Simchi-Levi and Zhao provide methods for evaluating stochastic , multi-echelon inventory systems , specifically, the queuing

  10. Emerging tools for continuous nutrient monitoring networks: Sensors advancing science and water resources protection

    Science.gov (United States)

    Pellerin, Brian; Stauffer, Beth A; Young, Dwane A; Sullivan, Daniel J.; Bricker, Suzanne B.; Walbridge, Mark R; Clyde, Gerard A; Shaw, Denice M

    2016-01-01

    Sensors and enabling technologies are becoming increasingly important tools for water quality monitoring and associated water resource management decisions. In particular, nutrient sensors are of interest because of the well-known adverse effects of nutrient enrichment on coastal hypoxia, harmful algal blooms, and impacts to human health. Accurate and timely information on nutrient concentrations and loads is integral to strategies designed to minimize risk to humans and manage the underlying drivers of water quality impairment. Using nitrate sensors as an example, we highlight the types of applications in freshwater and coastal environments that are likely to benefit from continuous, real-time nutrient data. The concurrent emergence of new tools to integrate, manage and share large data sets is critical to the successful use of nutrient sensors and has made it possible for the field of continuous nutrient monitoring to rapidly move forward. We highlight several near-term opportunities for Federal agencies, as well as the broader scientific and management community, that will help accelerate sensor development, build and leverage sites within a national network, and develop open data standards and data management protocols that are key to realizing the benefits of a large-scale, integrated monitoring network. Investing in these opportunities will provide new information to guide management and policies designed to protect and restore our nation’s water resources.

  11. The Global Network Neonatal Cause of Death algorithm for low-resource settings.

    Science.gov (United States)

    Garces, Ana L; McClure, Elizabeth M; Pérez, Wilton; Hambidge, K Michael; Krebs, Nancy F; Figueroa, Lester; Bose, Carl L; Carlo, Waldemar A; Tenge, Constance; Esamai, Fabian; Goudar, Shivaprasad S; Saleem, Sarah; Patel, Archana B; Chiwila, Melody; Chomba, Elwyn; Tshefu, Antoinette; Derman, Richard J; Hibberd, Patricia L; Bucher, Sherri; Liechty, Edward A; Bauserman, Melissa; Moore, Janet L; Koso-Thomas, Marion; Miodovnik, Menachem; Goldenberg, Robert L

    2017-06-01

    This study estimated the causes of neonatal death using an algorithm for low-resource areas, where 98% of the world's neonatal deaths occur. We enrolled women in India, Pakistan, Guatemala, the Democratic Republic of Congo, Kenya and Zambia from 2014 to 2016 and tracked their delivery and newborn outcomes for up to 28 days. Antenatal care and delivery symptoms were collected using a structured questionnaire, clinical observation and/or a physical examination. The Global Network Cause of Death algorithm was used to assign the cause of neonatal death, analysed by country and day of death. One-third (33.1%) of the 3068 neonatal deaths were due to suspected infection, 30.8% to prematurity, 21.2% to asphyxia, 9.5% to congenital anomalies and 5.4% did not have a cause of death assigned. Prematurity and asphyxia-related deaths were more common on the first day of life (46.7% and 52.9%, respectively), while most deaths due to infection occurred after the first day of life (86.9%). The distribution of causes was similar to global data reported by other major studies. The Global Network algorithm provided a reliable cause of neonatal death in low-resource settings and can be used to inform public health strategies to reduce mortality. ©2017 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

  12. Few Ant Species Play a Central Role Linking Different Plant Resources in a Network in Rupestrian Grasslands.

    Science.gov (United States)

    Costa, Fernanda V; Mello, Marco A R; Bronstein, Judith L; Guerra, Tadeu J; Muylaert, Renata L; Leite, Alice C; Neves, Frederico S

    2016-01-01

    Ant-plant associations are an outstanding model to study the entangled ecological interactions that structure communities. However, most studies of plant-animal networks focus on only one type of resource that mediates these interactions (e.g, nectar or fruits), leading to a biased understanding of community structure. New approaches, however, have made possible to study several interaction types simultaneously through multilayer networks models. Here, we use this approach to ask whether the structural patterns described to date for ant-plant networks hold when multiple interactions with plant-derived food rewards are considered. We tested whether networks characterized by different resource types differ in specialization and resource partitioning among ants, and whether the identity of the core ant species is similar among resource types. We monitored ant interactions with extrafloral nectaries, flowers, and fruits, as well as trophobiont hemipterans feeding on plants, for one year, in seven rupestrian grassland (campo rupestre) sites in southeastern Brazil. We found a highly tangled ant-plant network in which plants offering different resource types are connected by a few central ant species. The multilayer network had low modularity and specialization, but ant specialization and niche overlap differed according to the type of resource used. Beyond detecting structural differences across networks, our study demonstrates empirically that the core of most central ant species is similar across them. We suggest that foraging strategies of ant species, such as massive recruitment, may determine specialization and resource partitioning in ant-plant interactions. As this core of ant species is involved in multiple ecosystem functions, it may drive the diversity and evolution of the entire campo rupestre community.

  13. Insect-Flower Interaction Network Structure Is Resilient to a Temporary Pulse of Floral Resources from Invasive Rhododendron ponticum

    Science.gov (United States)

    Tiedeken, Erin Jo; Stout, Jane C.

    2015-01-01

    Invasive alien plants can compete with native plants for resources, and may ultimately decrease native plant diversity and/or abundance in invaded sites. This could have consequences for native mutualistic interactions, such as pollination. Although invasive plants often become highly connected in plant-pollinator interaction networks, in temperate climates they usually only flower for part of the season. Unless sufficient alternative plants flower outside this period, whole-season floral resources may be reduced by invasion. We hypothesized that the cessation of flowering of a dominant invasive plant would lead to dramatic, seasonal compositional changes in plant-pollinator communities, and subsequent changes in network structure. We investigated variation in floral resources, flower-visiting insect communities, and interaction networks during and after the flowering of invasive Rhododendron ponticum in four invaded Irish woodland sites. Floral resources decreased significantly after R. ponticum flowering, but the magnitude of the decrease varied among sites. Neither insect abundance nor richness varied between the two periods (during and after R. ponticum flowering), yet insect community composition was distinct, mostly due to a significant reduction in Bombus abundance after flowering. During flowering R. ponticum was frequently visited by Bombus; after flowering, these highly mobile pollinators presumably left to find alternative floral resources. Despite compositional changes, however, network structural properties remained stable after R. ponticum flowering ceased: generality increased, but quantitative connectance, interaction evenness, vulnerability, H’2 and network size did not change. This is likely because after R. ponticum flowering, two to three alternative plant species became prominent in networks and insects increased their diet breadth, as indicated by the increase in network-level generality. We conclude that network structure is robust to

  14. Insect-flower interaction network structure is resilient to a temporary pulse of floral resources from invasive Rhododendron ponticum.

    Science.gov (United States)

    Tiedeken, Erin Jo; Stout, Jane C

    2015-01-01

    Invasive alien plants can compete with native plants for resources, and may ultimately decrease native plant diversity and/or abundance in invaded sites. This could have consequences for native mutualistic interactions, such as pollination. Although invasive plants often become highly connected in plant-pollinator interaction networks, in temperate climates they usually only flower for part of the season. Unless sufficient alternative plants flower outside this period, whole-season floral resources may be reduced by invasion. We hypothesized that the cessation of flowering of a dominant invasive plant would lead to dramatic, seasonal compositional changes in plant-pollinator communities, and subsequent changes in network structure. We investigated variation in floral resources, flower-visiting insect communities, and interaction networks during and after the flowering of invasive Rhododendron ponticum in four invaded Irish woodland sites. Floral resources decreased significantly after R. ponticum flowering, but the magnitude of the decrease varied among sites. Neither insect abundance nor richness varied between the two periods (during and after R. ponticum flowering), yet insect community composition was distinct, mostly due to a significant reduction in Bombus abundance after flowering. During flowering R. ponticum was frequently visited by Bombus; after flowering, these highly mobile pollinators presumably left to find alternative floral resources. Despite compositional changes, however, network structural properties remained stable after R. ponticum flowering ceased: generality increased, but quantitative connectance, interaction evenness, vulnerability, H'2 and network size did not change. This is likely because after R. ponticum flowering, two to three alternative plant species became prominent in networks and insects increased their diet breadth, as indicated by the increase in network-level generality. We conclude that network structure is robust to

  15. Effective Knowledge Development in Secondary Schools Educational Level in Contemporary Information Age: Assessment of Availability of Electronic Information Resources in Nigerian School Libraries

    Science.gov (United States)

    Bello, Stephen Adeyemi; Ojo, Funmilayo Roseline; Ocheje, Charles Bala

    2015-01-01

    Relevant electronic information resources in contemporary information age are necessity to buttress teaching and learning for effective knowledge development in educational institutions. The purpose of the study is to know the state of availability of electronic information resources in government owned secondary school libraries in Ijumu Local…

  16. Evaluating Career Development Resources: Lessons from the Earth Science Women's Network (ESWN)

    Science.gov (United States)

    Kogan, M.; Laursen, S. L.

    2010-12-01

    Retention of geoscientists throughout the professional pipeline is especially challenging in the case of groups that are already underrepresented in science, including racial minorities and women. The Earth Science Women’s Network (ESWN) is a professional network of early-career female geoscientists that provides its members with a variety of career resources, through both informal, online and in-person networking and formal career development workshops. The group’s members are of diverse nationalities and racial/ethnic backgrounds, of various age cohorts and career stages, but primarily graduate students, postdocs, and early-career researchers. With funding from an NSF ADVANCE grant to ESWN, we have conducted a detailed survey of ESWN members as part of an evaluation-with-research study that aims to determine the career needs of young geoscientists. The survey data provide information about members’ personal and professional situations, their professional development needs, and obstacles they face as young women scientists. ESWN members indicated a variety of areas of professional growth that would advance their scientific careers, but at all career stages, members chose expanding their professional networks as among their top career needs. Professional networking has established benefits for retention of people from groups underrepresented in science, including women: it introduces young scientists to career best practices and advancement opportunities, provides access to role models, and creates a sense of community. ESWN members strongly indicate that their professional networks benefited from their involvement with the Network. The community aspect of network-building is especially important for people from underrepresented groups, as they often feel alone due to the lack of role models. The intimate character of the ESWN discussion list greatly contributes to its members’ sense of community. Moreover, personal concerns and professional success are

  17. Acute pharmacologically induced shifts in serotonin availability abolish emotion-selective responses to negative face emotions in distinct brain networks.

    Science.gov (United States)

    Grady, Cheryl L; Siebner, Hartwig R; Hornboll, Bettina; Macoveanu, Julian; Paulson, Olaf B; Knudsen, Gitte M

    2013-05-01

    Pharmacological manipulation of serotonin availability can alter the processing of facial expressions of emotion. Using a within-subject design, we measured the effect of serotonin on the brain's response to aversive face emotions with functional MRI while 20 participants judged the gender of neutral, fearful and angry faces. In three separate and counterbalanced sessions, participants received citalopram (CIT) to raise serotonin levels, underwent acute tryptophan depletion (ATD) to lower serotonin, or were studied without pharmacological challenge (Control). An analysis designed to identify distributed brain responses identified two brain networks with modulations of activity related to face emotion and serotonin level. The first network included the left amygdala, bilateral striatum, and fusiform gyri. During the Control session this network responded only to fearful faces; increasing serotonin decreased this response to fear, whereas reducing serotonin enhanced the response of this network to angry faces. The second network involved bilateral amygdala and ventrolateral prefrontal cortex, and these regions also showed increased activity to fear during the Control session. Both drug challenges enhanced the neural response of this set of regions to angry faces, relative to Control, and CIT also enhanced activity for neutral faces. The net effect of these changes in both networks was to abolish the selective response to fearful expressions. These results suggest that a normal level of serotonin is critical for maintaining a differentiated brain response to threatening face emotions. Lower serotonin leads to a broadening of a normally fear-specific response to anger, and higher levels reduce the differentiated brain response to aversive face emotions. Copyright © 2012 Elsevier B.V. and ECNP. All rights reserved.

  18. An examination of network position and childhood relational aggression: integrating resource control and social exchange theories.

    Science.gov (United States)

    Neal, Jennifer Watling; Cappella, Elise

    2012-01-01

    Applying resource control theory and social exchange theory, we examined the social network conditions under which elementary age children were likely to engage in relational aggression. Data on classroom peer networks and peer-nominated behaviors were collected on 671 second- through fourth-grade children in 34 urban, low-income classrooms. Nested regression models with robust cluster standard errors demonstrated that the association between children's number of relationships and their levels of relational aggression was moderated by the number of relationships that their affiliates had. Children with more peer relationships (i.e., higher network centrality) exhibited higher levels of relational aggression, but only when these relationships were with peers who had fewer connections themselves (i.e., poorly connected peers). This finding remained significant even when controlling for common predictors of relational aggression including gender, overt aggression, prosocial behavior, victimization, social preference, and perceived popularity. Results are discussed in terms of their implications for advancing the literature on childhood relational aggression and their practical applications for identifying children at risk for these behaviors. © 2012 Wiley Periodicals, Inc.

  19. Changma onset definition in Korea using the available water resources index and its relation to the Antarctic oscillation

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Ki-Seon [National Typhoon Center/Korea Meteorological Administration, Jeju (Korea, Republic of); Wang, Bin [University of Hawaii at Manoa, Department of Meteorology, International Pacific Research Center, Honolulu, HI (United States); Kim, Do-Woo [Pukyong National University, Department of Environmental Atmospheric Sciences, Busan (Korea, Republic of)

    2012-02-15

    This study defines the Changma onset using the available water resources index (AWRI) for 25 years (1985-2009) and verifies the validity of this definition. The three conditions for defining the Changma onset are established as follows: (i) The first day exceeding the June AWRI (threshold) averaged over the 25-year period. (ii) The continuation of the value over the threshold for at least 1 week after the onset. (iii) After the continuation of more than 1 week, the non-continuation of the value under the threshold for at least 1 week. The 25-year average Changma onset date is 24 June with a standard deviation of 9 days. The defined Changma onset is verified through the analysis on the relationship with the Antarctic oscillation (AAO). AAO in June shows a high correlation with not only the Changma onset but also the June precipitation (AWRI) in Korea. These three variables are influenced by Mascarene and Australian (positive AAO pattern) highs from in the preceding March. When these two pressure systems develop, the cold cross-equatorial flow in the direction from the region around Australia to the equator is intensified, which in turn, forces a western North Pacific high (WNPH) to develop northward; this eventually drives the rain belt north. As a result, the Changma begins early in the positive AAO phase, and the June precipitation increases in Korea. In addition, a WNPH that develops more northward increases the landfalling frequency of tropical cyclones in Korea, which plays an important role in increasing the June precipitation. (orig.)

  20. Regional Algal Biofuel Production Potential in the Coterminous United States as Affected by Resource Availability Trade-offs

    Energy Technology Data Exchange (ETDEWEB)

    Venteris, Erik R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Skaggs, Richard [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wigmosta, Mark S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Coleman, Andre M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2014-03-15

    The warm sunny climate and unoccupied arid lands in the American southwest are favorable factors for algae cultivation. However, additional resources affect the overall viability of specific sites and regions. We investigated the tradeoffs between growth rate, water, and CO2 availability and costs for two strains: N. salina and Chlorella sp. We conducted site selection exercises (~88,000 US sites) to produce 21 billion gallons yr-1 (BGY) of renewable diesel (RD). Experimental trials from the National Alliance for Advanced Biofuels and Bio-Products (NAABB) team informed the growth model of our Biomass Assessment Tool (BAT). We simulated RD production by both lipid extraction and hydrothermal liquefaction. Sites were prioritized by the net value of biofuel minus water and flue gas costs. Water cost models for N. salina were based on seawater and high salinity groundwater and for Chlorella, fresh and brackish groundwater. CO2 costs were based on a flue gas delivery model. Selections constrained by production and water were concentrated along the Gulf of Mexico and southeast Atlantic coasts due to high growth rates and low water costs. Adding flue gas constraints increased the spatial distribution, but the majority of sites remained in the southeast. The 21 BGY target required ~3.8 million hectares of mainly forest (41.3%) and pasture (35.7%). Exclusion in favor of barren and scrub lands forced most production to the southwestern US, but with increased water consumption (5.7 times) and decreased economic efficiency (-38%).