Science.gov

Sample records for multi-user cooperative diversity

  1. Performance improvement of OFDM-FSO multi-user communication system with combined transmit frequency diversity and receive space diversity

    NASA Astrophysics Data System (ADS)

    Kumar, Pravindra; Srivastava, Anand

    2016-05-01

    Orthogonal frequency division multiplexed (OFDM) based free space optical (FSO) communication link gives improved performance because of narrow-band interference, improved robustness against fading and high bandwidth efficiency. It is further improved using transmit frequency diversity and space diversity at the receiver. In this paper, we propose to use OFDM architecture combined with spreading code in electrical domain, referred as code division multiplexed-orthogonal frequency division multiplexing (CDM-OFDM) which provides frequency diversity at the transmitter and using more than one receiver to get receive diversity. Analytical model of CDM-OFDM-FSO communication system with photo-detector space diversity using maximal ratio combining (MRC) is analyzed in the presence of turbulent atmosphere, multi-user-interference (MUI) and timing jitter. The error performance is computed in terms of receiver sensitivity and bit-error-rate (BER). In the analysis, Gamma-Gamma distribution is considered for atmospheric turbulence. The performance of OFDM-FSO link and CDM-OFDM-FSO link is compared. It is seen that for multiple users, CDM-OFDM-FSO link with transmit and receive diversity gives improved performance as compared to OFDM-FSO link.

  2. Cooperative multi-user detection and ranging based on pseudo-random codes

    NASA Astrophysics Data System (ADS)

    Morhart, C.; Biebl, E. M.

    2009-05-01

    We present an improved approach for a Round Trip Time of Flight distance measurement system. The system is intended for the usage in a cooperative localisation system for automotive applications. Therefore, it is designed to address a large number of communication partners per measurement cycle. By using coded signals in a time divison multiple access order, we can detect a large number of pedestrian sensors with just one car sensor. We achieve this by using very short transmit bursts in combination with a real time correlation algorithm. Futhermore, the correlation approach offers real time data, concerning the time of arrival, that can serve as a trigger impulse for other comunication systems. The distance accuracy of the correlation result was further increased by adding a fourier interpolation filter. The system performance was checked with a prototype at 2.4 GHz. We reached a distance measurement accuracy of 12 cm at a range up to 450 m.

  3. Managing a Safe and Successful Multi-User Spaceport

    NASA Technical Reports Server (NTRS)

    Dacko, Taylor; Ketterer, Kirk; Meade, Phillip

    2016-01-01

    Encouraged by the creation of the Office of Commercial Space Transportation within the U.S. Federal Aviation Administration (FAA) in 1984 and the Commercial Space Act of 1998, the National Aeronautics and Space Administration (NASA) now relies on an extensive network of support from commercial companies and organizations. At NASA's Kennedy Space Center (KSC), this collaboration opens competitive opportunities for launch providers, including repurposing underutilized Shuttle Program resources, constructing new facilities, and utilizing center services and laboratories. The resulting multi-user spaceport fosters diverse activity, though it engenders risk from hazards associated with various spaceflight processing activities. The KSC Safety & Mission Assurance (S&MA) Directorate, in coordination with the center's Spaceport Integration and Center Planning & Development organizations, has developed a novel approach to protect NASA's workforce, critical assets, and the public from hazardous, space-related activity associated with KSC's multi-user spaceport. For NASA KSC S&MA, the transformation to a multi-user spaceport required implementing methods to foster safe and successful commercial activity while resolving challenges involving: Retirement of the Space Shuttle program; Co-location of multiple NASA programs; Relationships between the NASA programs; Complex relationships between NASA programs and commercial partner operations in exclusive-use facilities; Complex relationships between NASA programs and commercial partner operations in shared-use facilities. NASA KSC S&MA challenges were met with long-term planning and solutions involving cooperation with the Spaceport Integration and Services Directorate. This directorate is responsible for managing active commercial partnerships with customer advocacy and services management, providing a dedicated and consistent level of support to a wide array of commercial operations. This paper explores these solutions, their

  4. Do students with higher self-efficacy exhibit greater and more diverse scientific inquiry skills: An exploratory investigation in "River City", a multi-user virtual environment

    NASA Astrophysics Data System (ADS)

    Ketelhut, Diane Jass

    In this thesis, I conduct an exploratory study to investigate the relationship between students' self-efficacy on entry into authentic scientific activity and the scientific inquiry behaviors they employ while engaged in that process, over time. Scientific inquiry has been a major standard in most science education policy doctrines for the past two decades and is exemplified by activities such as making observations, formulating hypotheses, gathering and analyzing data, and forming conclusions from that data. The self-efficacy literature, however, indicates that self-efficacy levels affect perseverance and engagement. This study investigated the relationship between these two constructs. The study is conducted in a novel setting, using an innovative science curriculum delivered through an interactive computer technology that recorded each student's conversations, movements, and activities while behaving as a practicing scientist in a "virtual world" called River City. River City is a Multi-User Virtual Environment designed to engage students in a collaborative scientific inquiry-based learning experience. As a result, I was able to follow students' moment-by-moment choices of behavior while they were behaving as scientists. I collected data on students' total scientific inquiry behaviors over three visits to River City, as well as the number of sources from which they gathered their scientific data. I analyzed my longitudinal data on the 96 seventh-graders using individual growth modeling. I found that self-efficacy played a role in the number of data-gathering behaviors students engaged in initially, with high self-efficacy students engaging in more data gathering than students with low self-efficacy. However, the impact of student self-efficacy on rate of change in data gathering behavior differed by gender; by the end of the study, student self-efficacy did not impact data gathering. In addition, students' level of self-efficacy did not affect how many different

  5. Multi-user quantum cryptography

    NASA Astrophysics Data System (ADS)

    Wang, Bing C.; Kumavor, Patrick; Yelin, Susanne F.; Beal, Alan C.

    2005-10-01

    Quantum cryptography applies the uncertainty principle and the no-cloning theorem of quantum mechanics to provide ultra-secure encryption key distribution between two parties. Present quantum cryptography technologies provide encryption key distribution between two parties. However, practical implementations encryption key distribution schemes require establishing secure quantum communications amongst multiple users. In this talk, we survey some of the state of the art quantum encryption deployment in communication networks. We will also discuss some common topologies that are being considered for multi-user quantum encryption networks. The performance of the multi-user quantum key distribution systems is then compared for four different optical network topologies: the Sagnac-based fiber ring, the wavelength routed, the passive star and the bus network. Their performances are compared and analyzed using quantum bit error rate analysis.

  6. University multi-user facility survey-2010.

    PubMed

    Riley, Melissa B

    2011-12-01

    Multi-user facilities serve as a resource for many universities. In 2010, a survey was conducted investigating possible changes and successful characteristics of multi-user facilities, as well as identifying problems in facilities. Over 300 surveys were e-mailed to persons identified from university websites as being involved with multi-user facilities. Complete responses were received from 36 facilities with an average of 20 years of operation. Facilities were associated with specific departments (22%), colleges (22%), and university research centers (8.3%) or were not affiliated with any department or college within the university (47%). The five most important factors to succeed as a multi-user facility were: 1) maintaining an experienced, professional staff in an open atmosphere; 2) university-level support providing partial funding; 3) broad client base; 4) instrument training programs; and 5) an effective leader and engaged strategic advisory group. The most significant problems were: 1) inadequate university financial support and commitment; 2) problems recovering full service costs from university subsidies and user fees; 3) availability of funds to repair and upgrade equipment; 4) inability to retain highly qualified staff; and 5) unqualified users dirtying/damaging equipment. Further information related to these issues and to fee structure was solicited. Overall, there appeared to be a decline in university support for facilities and more emphasis on securing income by serving clients outside of the institution and by obtaining grants from entities outside of the university. PMID:22131888

  7. Interactive diversity promotes the evolution of cooperation in structured populations

    NASA Astrophysics Data System (ADS)

    Su, Qi; Li, Aming; Zhou, Lei; Wang, Long

    2016-10-01

    Evolutionary games on networks traditionally assume that each individual adopts an identical strategy to interact with all its neighbors in each generation. Considering the prevalent diversity of individual interactions in the real society, here we propose the concept of interactive diversity, which allows individuals to adopt different strategies against different neighbors in each generation. We investigate the evolution of cooperation based on the edge dynamics rather than the traditional nodal dynamics in networked systems. The results show that, without invoking any other mechanisms, interactive diversity drives the frequency of cooperation to a high level for a wide range of parameters in both well-mixed and structured populations. Even in highly connected populations, cooperation still thrives. When interactive diversity and large topological heterogeneity are combined together, however, in the relaxed social dilemma, cooperation level is lower than that with just one of them, implying that the combination of many promotive factors may make a worse outcome. By an analytical approximation, we get the condition under which interactive diversity provides more advantages for cooperation than traditional evolutionary dynamics does. Numerical simulations validating the approximation are also presented. Our work provides a new line to explore the latent relation between the ubiquitous cooperation and individuals’ distinct responses in different interactions. The presented results suggest that interactive diversity should receive more attention in pursuing mechanisms fostering cooperation.

  8. Relational diversity promotes cooperation in prisoner's dilemma games.

    PubMed

    Xu, Bo; Wang, Jianwei; Deng, Ruipu; Li, Miao

    2014-01-01

    Relational diversity can be characterized by heterogeneous distributions of tie strengths in social networks and this diversity is present not only among humans, but throughout the animal world. We account for this observation by analyzing two network datasets from Facebook. We measure the strength of a tie by calculating the extent of overlap of friends between the two individuals. Based on the previous findings in human experiments, we argue that it is very unlikely that players will allocate their investments equally to their neighbors. There is a tendency that players prefer to donate more to their intimate friends. We find that if players preferentially allocate their investments to their good friends, cooperation will be promoted in PDG. We proved that the facilitation of the cooperative strategy relies mostly on the cooperative allies between best friends, resulting in the formation of cooperative clusters which are able to prevail against the defectors even when there is a large cost to cooperate. Moreover, we discover that the effect of relational diversity cannot be analyzed by adopting classical complex networks models, because neither of the artificial networks is able to produce networks with diverse distributions of tie strengths. It is of vital importance to introduce real social networks to study the influence of diverse relations especially when it comes to humans. This research proposes a brand new perspective to understand the influence of social relations on the emergence of cooperation in evolutionary prisoner's dilemma games. PMID:25474354

  9. The interplay between cooperativity and diversity in model threshold ensembles.

    PubMed

    Cervera, Javier; Manzanares, José A; Mafe, Salvador

    2014-10-01

    The interplay between cooperativity and diversity is crucial for biological ensembles because single molecule experiments show a significant degree of heterogeneity and also for artificial nanostructures because of the high individual variability characteristic of nanoscale units. We study the cross-effects between cooperativity and diversity in model threshold ensembles composed of individually different units that show a cooperative behaviour. The units are modelled as statistical distributions of parameters (the individual threshold potentials here) characterized by central and width distribution values. The simulations show that the interplay between cooperativity and diversity results in ensemble-averaged responses of interest for the understanding of electrical transduction in cell membranes, the experimental characterization of heterogeneous groups of biomolecules and the development of biologically inspired engineering designs with individually different building blocks. PMID:25142516

  10. The interplay between cooperativity and diversity in model threshold ensembles.

    PubMed

    Cervera, Javier; Manzanares, José A; Mafe, Salvador

    2014-10-01

    The interplay between cooperativity and diversity is crucial for biological ensembles because single molecule experiments show a significant degree of heterogeneity and also for artificial nanostructures because of the high individual variability characteristic of nanoscale units. We study the cross-effects between cooperativity and diversity in model threshold ensembles composed of individually different units that show a cooperative behaviour. The units are modelled as statistical distributions of parameters (the individual threshold potentials here) characterized by central and width distribution values. The simulations show that the interplay between cooperativity and diversity results in ensemble-averaged responses of interest for the understanding of electrical transduction in cell membranes, the experimental characterization of heterogeneous groups of biomolecules and the development of biologically inspired engineering designs with individually different building blocks.

  11. The interplay between cooperativity and diversity in model threshold ensembles

    PubMed Central

    Cervera, Javier; Manzanares, José A.; Mafe, Salvador

    2014-01-01

    The interplay between cooperativity and diversity is crucial for biological ensembles because single molecule experiments show a significant degree of heterogeneity and also for artificial nanostructures because of the high individual variability characteristic of nanoscale units. We study the cross-effects between cooperativity and diversity in model threshold ensembles composed of individually different units that show a cooperative behaviour. The units are modelled as statistical distributions of parameters (the individual threshold potentials here) characterized by central and width distribution values. The simulations show that the interplay between cooperativity and diversity results in ensemble-averaged responses of interest for the understanding of electrical transduction in cell membranes, the experimental characterization of heterogeneous groups of biomolecules and the development of biologically inspired engineering designs with individually different building blocks. PMID:25142516

  12. Diversity of rationality affects the evolution of cooperation

    NASA Astrophysics Data System (ADS)

    Chen, Yu-Zhong; Huang, Zi-Gang; Wang, Sheng-Jun; Zhang, Yan; Wang, Ying-Hai

    2009-05-01

    By modifying the Fermi updating rule, we present the diversity of individual rationality to the evolutionary prisoner’s dilemma game, and our results shows that this diversity heavily influences the evolution of cooperation. Cluster-forming mechanism of cooperators can either be highly enhanced or severely deteriorated by different distributions of rationality. Slight change in the rationality distribution may transfer the whole system from the global absorbing state of cooperators to that of defectors. Based on mean-field argument, quantitative analysis of the stability of cooperative clusters reveals the critical role played by agents with moderate degree values in the evolution of the whole system. The inspiration from our work may provide us a deeper comprehension toward some social phenomena.

  13. Cooperative Learning: A Diversified Pedagogy for Diverse Classrooms

    ERIC Educational Resources Information Center

    Sharan, Yael

    2010-01-01

    As a generic and diversified pedagogy, cooperative learning (CL) reaches out to the field of intercultural education with an offer to establish a reciprocal relationship. After a short description of the diversity of CL and a brief exploration of the influence that culture has on learning, this paper depicts how the partnership between CL and…

  14. Evolution of cooperation driven by the diversity of emotions

    NASA Astrophysics Data System (ADS)

    Xie, Neng-gang; Zhen, Kai-xuan; Wang, Chao; Ye, Ye; Wang, Lu

    2015-01-01

    Biotic individuals often compare their own payoffs with those of others, which results in endogenetic emotions ranging from compassion to harshness towards a weaker player or from respect to envy feeling against a stronger fellow. Consequently, the individual reaction can be a cooperative or defect act. Our paper establishes possible interactions between emotional characteristics and behaviour modes of individuals. For this purpose, a genetic algorithm is used to study the evolutionary process within the framework of a Prisoner's Dilemma game. Our results highlight that the diversity of emotions can emerge spontaneously that is fruitful for the general cooperative act. Furthermore, it turned out that compassion is more important than respect, but both attitudes have better adaptability than harshness or envy feeling.

  15. Multi-User Droplet Combustion Apparatus - Flame Extinguishment Experiment

    NASA Technical Reports Server (NTRS)

    Williams, Forman A.; Nayagam, Vedha; Choi, Mun Y.; Dryer, Frederick L.; Shaw, Benjamin D.

    2009-01-01

    Multi-User Droplet Combustion Apparatus Flame Extinguishment Experiment (MDCA-FLEX) will assess the effectiveness of fire suppressants in microgravity and quantify the effect of different possible crew exploration atmospheres on fire suppression. The goal of this research is to provide definition and direction for large scale fire suppression tests and selection of the fire suppressant for next generation crew exploration vehicles.

  16. Teacher Practice in Multi User Virtual Environments: A Fourth Space

    ERIC Educational Resources Information Center

    Calandra, Brendan; Puvirajah, Anton

    2014-01-01

    Practicing teaching is an important aspect of teacher education, however, its implementation can be limited due to the constraints and risks related to practicing in actual schools. There is evidence in the literature of Multi User Virtual Environments (MUVEs) being used as spaces for training, especially in fields where the costs associated with…

  17. Introducing ORACLE: Library Processing in a Multi-User Environment.

    ERIC Educational Resources Information Center

    Queensland Library Board, Brisbane (Australia).

    Currently being developed by the State Library of Queensland, Australia, ORACLE (On-Line Retrieval of Acquisitions, Cataloguing, and Circulation Details for Library Enquiries) is a computerized library system designed to provide rapid processing of library materials in a multi-user environment. It is based on the Australian MARC format and fully…

  18. Multi-User Hardware Solutions to Combustion Science ISS Research

    NASA Technical Reports Server (NTRS)

    Otero, Angel M.

    2001-01-01

    In response to the budget environment and to expand on the International Space Station (ISS) Fluids and Combustion Facility (FCF) Combustion Integrated Rack (CIR), common hardware approach, the NASA Combustion Science Program shifted focus in 1999 from single investigator PI (Principal Investigator)-specific hardware to multi-user 'Minifacilities'. These mini-facilities would take the CIR common hardware philosophy to the next level. The approach that was developed re-arranged all the investigations in the program into sub-fields of research. Then common requirements within these subfields were used to develop a common system that would then be complemented by a few PI-specific components. The sub-fields of research selected were droplet combustion, solids and fire safety, and gaseous fuels. From these research areas three mini-facilities have sprung: the Multi-user Droplet Combustion Apparatus (MDCA) for droplet research, Flow Enclosure for Novel Investigations in Combustion of Solids (FEANICS) for solids and fire safety, and the Multi-user Gaseous Fuels Apparatus (MGFA) for gaseous fuels. These mini-facilities will develop common Chamber Insert Assemblies (CIA) and diagnostics for the respective investigators complementing the capability provided by CIR. Presently there are four investigators for MDCA, six for FEANICS, and four for MGFA. The goal of these multi-user facilities is to drive the cost per PI down after the initial development investment is made. Each of these mini-facilities will become a fixture of future Combustion Science NASA Research Announcements (NRAs), enabling investigators to propose against an existing capability. Additionally, an investigation is provided the opportunity to enhance the existing capability to bridge the gap between the capability and their specific science requirements. This multi-user development approach will enable the Combustion Science Program to drive cost per investigation down while drastically reducing the time

  19. Molecular Cooperativity Governs Diverse and Monoallelic Olfactory Receptor Expression

    NASA Astrophysics Data System (ADS)

    Xing, Jianhua; Tian, Xiaojun; Zhang, Hang; Sannerud, Jens

    Multiple-objective optimization is common in biological systems. In the mammalian olfactory system, each sensory neuron stochastically expresses only one out of up to thousands of olfactory receptor (OR) gene alleles; at organism level the types of expressed ORs need to be maximized. The molecular mechanism of this Nobel-Prize winning puzzle remains unresolved after decades of extensive studies. Existing models focus only on monoallele activation, and cannot explain recent observations in mutants, especially the reduced global diversity of expressed ORs in G9a/GLP knockouts. In this work we integrated existing information on OR expression, and proposed an evolutionarily optimized three-layer regulation mechanism, which includes zonal segregation, epigenetic and enhancer competition coupled to a negative feedback loop. This model not only recapitulates monoallelic OR expression, but also elucidates how the olfactory system maximizes and maintains the diversity of OR expression. The model is validated by several experimental results, and particularly underscores cooperativity and synergy as a general design principle of multi-objective optimization in biology. The work is supported by the NIGMS/DMS Mathematical Biology program.

  20. Presence of a loner strain maintains cooperation and diversity in well-mixed bacterial communities.

    PubMed

    Inglis, R F; Biernaskie, J M; Gardner, A; Kümmerli, R

    2016-01-13

    Cooperation and diversity abound in nature despite cooperators risking exploitation from defectors and superior competitors displacing weaker ones. Understanding the persistence of cooperation and diversity is therefore a major problem for evolutionary ecology, especially in the context of well-mixed populations, where the potential for exploitation and displacement is greatest. Here, we demonstrate that a 'loner effect', described by economic game theorists, can maintain cooperation and diversity in real-world biological settings. We use mathematical models of public-good-producing bacteria to show that the presence of a loner strain, which produces an independent but relatively inefficient good, can lead to rock-paper-scissor dynamics, whereby cooperators outcompete loners, defectors outcompete cooperators and loners outcompete defectors. These model predictions are supported by our observations of evolutionary dynamics in well-mixed experimental communities of the bacterium Pseudomonas aeruginosa. We find that the coexistence of cooperators and defectors that produce and exploit, respectively, the iron-scavenging siderophore pyoverdine, is stabilized by the presence of loners with an independent iron-uptake mechanism. Our results establish the loner effect as a simple and general driver of cooperation and diversity in environments that would otherwise favour defection and the erosion of diversity.

  1. Presence of a loner strain maintains cooperation and diversity in well-mixed bacterial communities

    PubMed Central

    Inglis, R. F.; Biernaskie, J. M.; Gardner, A.; Kümmerli, R.

    2016-01-01

    Cooperation and diversity abound in nature despite cooperators risking exploitation from defectors and superior competitors displacing weaker ones. Understanding the persistence of cooperation and diversity is therefore a major problem for evolutionary ecology, especially in the context of well-mixed populations, where the potential for exploitation and displacement is greatest. Here, we demonstrate that a ‘loner effect’, described by economic game theorists, can maintain cooperation and diversity in real-world biological settings. We use mathematical models of public-good-producing bacteria to show that the presence of a loner strain, which produces an independent but relatively inefficient good, can lead to rock–paper–scissor dynamics, whereby cooperators outcompete loners, defectors outcompete cooperators and loners outcompete defectors. These model predictions are supported by our observations of evolutionary dynamics in well-mixed experimental communities of the bacterium Pseudomonas aeruginosa. We find that the coexistence of cooperators and defectors that produce and exploit, respectively, the iron-scavenging siderophore pyoverdine, is stabilized by the presence of loners with an independent iron-uptake mechanism. Our results establish the loner effect as a simple and general driver of cooperation and diversity in environments that would otherwise favour defection and the erosion of diversity. PMID:26763707

  2. Presence of a loner strain maintains cooperation and diversity in well-mixed bacterial communities.

    PubMed

    Inglis, R F; Biernaskie, J M; Gardner, A; Kümmerli, R

    2016-01-13

    Cooperation and diversity abound in nature despite cooperators risking exploitation from defectors and superior competitors displacing weaker ones. Understanding the persistence of cooperation and diversity is therefore a major problem for evolutionary ecology, especially in the context of well-mixed populations, where the potential for exploitation and displacement is greatest. Here, we demonstrate that a 'loner effect', described by economic game theorists, can maintain cooperation and diversity in real-world biological settings. We use mathematical models of public-good-producing bacteria to show that the presence of a loner strain, which produces an independent but relatively inefficient good, can lead to rock-paper-scissor dynamics, whereby cooperators outcompete loners, defectors outcompete cooperators and loners outcompete defectors. These model predictions are supported by our observations of evolutionary dynamics in well-mixed experimental communities of the bacterium Pseudomonas aeruginosa. We find that the coexistence of cooperators and defectors that produce and exploit, respectively, the iron-scavenging siderophore pyoverdine, is stabilized by the presence of loners with an independent iron-uptake mechanism. Our results establish the loner effect as a simple and general driver of cooperation and diversity in environments that would otherwise favour defection and the erosion of diversity. PMID:26763707

  3. Cooperative Learning--A Double-Edged Sword: A Cooperative Learning Model for Use with Diverse Student Groups

    ERIC Educational Resources Information Center

    Baker, Trish; Clark, Jill

    2010-01-01

    Although very little research has been done on cooperative learning (CL) in New Zealand, international research is positive about the educational benefits of working in culturally diverse groups. This paper presents the findings of a research project examining New Zealand experiences with CL in multicultural groups. Data were collected via surveys…

  4. Cooperative Learning: A Response to Linguistic and Cultural Diversity. Language in Education: Theory and Practice 81.

    ERIC Educational Resources Information Center

    Holt, Daniel D., Ed.

    Essays on cooperative learning focus on the use of this strategy to address the special needs of linguistically and culturally diverse student groups in elementary and secondary education. The volume contains several essays on theory, principles, and techniques of cooperative learning and a series of model instructional units for a variety of…

  5. Achieving Common Expectations for Overall Goals amid Diversity among Cooperative Extension Faculty.

    ERIC Educational Resources Information Center

    Taylor, Barbara

    As a part of the initial phase of a strategic planning effort for the development of Florida's 1988 through 1991 long-range cooperative extension program, an effort was initiated to achieve common expectations for overall organizational mission and purpose among diverse cooperative extension faculty. The unification effort included the following…

  6. Multilevel and multi-user sustainability assessment of farming systems

    SciTech Connect

    Van Passel, Steven; Meul, Marijke

    2012-01-15

    Sustainability assessment is needed to build sustainable farming systems. A broad range of sustainability concepts, methodologies and applications already exists. They differ in level, focus, orientation, measurement, scale, presentation and intended end-users. In this paper we illustrate that a smart combination of existing methods with different levels of application can make sustainability assessment more profound, and that it can broaden the insights of different end-user groups. An overview of sustainability assessment tools on different levels and for different end-users shows the complementarities and the opportunities of using different methods. In a case-study, a combination of the sustainable value approach (SVA) and MOTIFS is used to perform a sustainability evaluation of farming systems in Flanders. SVA is used to evaluate sustainability at sector level, and is especially useful to support policy makers, while MOTIFS is used to support and guide farmers towards sustainability at farm level. The combined use of the two methods with complementary goals can widen the insights of both farmers and policy makers, without losing the particularities of the different approaches. To stimulate and support further research and applications, we propose guidelines for multilevel and multi-user sustainability assessments. - Highlights: Black-Right-Pointing-Pointer We give an overview of sustainability assessment tools for agricultural systems. Black-Right-Pointing-Pointer SVA and MOTIFS are used to evaluate the sustainability of dairy farming in Flanders. Black-Right-Pointing-Pointer Combination of methods with different levels broadens the insights of different end-user groups. Black-Right-Pointing-Pointer We propose guidelines for multilevel and multi-user sustainability assessments.

  7. Center Planning and Development: Multi-User Spaceport Initiatives

    NASA Technical Reports Server (NTRS)

    Kennedy, Christopher John

    2015-01-01

    The Vehicle Assembly building at NASAs Kennedy Space Center has been used since 1966 to vertically assemble every launch vehicle, since the Apollo Program, launched from Launch Complex 39 (LC-39). After the cancellation of the Constellation Program in 2010 and the retirement of the Space Shuttle Program in 2011, the VAB faced an uncertain future. As the Space Launch System (SLS) gained a foothold as the future of American spaceflight to deep space, NASA was only using a portion of the VABs initial potential. With three high bays connected to the Crawler Way transportation system, the potential exists for up to three rockets to be simultaneously processed for launch. The Kennedy Space Center (KSC) Master plan, supported by the Center Planning and Development (CPD) Directorate, is guiding Kennedy toward a 21st century multi-user spaceport. This concept will maintain Kennedy as the United States premier gateway to space and provide multi-user operations through partnerships with the commercial aerospace industry. Commercial aerospace companies, now tasked with transporting cargo and, in the future, astronauts to the International Space Station (ISS) via the Commercial Resupply Service (CRS) and Commercial Crew Program (CCP), are a rapidly growing industry with increasing capabilities to make launch operations more economical for both private companies and the government. Commercial operations to Low Earth Orbit allow the government to focus on travel to farther destinations through the SLS Program. With LC-39B designated as a multi-use launch pad, companies seeking to use it will require an integration facility to assemble, integrate, and test their launch vehicle. An Announcement for Proposals (AFP) was released in June, beginning the process of finding a non-NASA user for High Bay 2 (HB2) and the Mobile Launcher Platforms (MLPs). An Industry Day, a business meeting and tour for interested companies and organizations, was also arranged to identify and answer any

  8. Social diversity promotes the emergence of cooperation in public goods games.

    PubMed

    Santos, Francisco C; Santos, Marta D; Pacheco, Jorge M

    2008-07-10

    Humans often cooperate in public goods games and situations ranging from family issues to global warming. However, evolutionary game theory predicts that the temptation to forgo the public good mostly wins over collective cooperative action, and this is often also seen in economic experiments. Here we show how social diversity provides an escape from this apparent paradox. Up to now, individuals have been treated as equivalent in all respects, in sharp contrast with real-life situations, where diversity is ubiquitous. We introduce social diversity by means of heterogeneous graphs and show that cooperation is promoted by the diversity associated with the number and size of the public goods game in which each individual participates and with the individual contribution to each such game. When social ties follow a scale-free distribution, cooperation is enhanced whenever all individuals are expected to contribute a fixed amount irrespective of the plethora of public goods games in which they engage. Our results may help to explain the emergence of cooperation in the absence of mechanisms based on individual reputation and punishment. Combining social diversity with reputation and punishment will provide instrumental clues on the self-organization of social communities and their economical implications.

  9. Social diversity and promotion of cooperation in the spatial prisoner's dilemma game

    NASA Astrophysics Data System (ADS)

    Perc, Matjaž; Szolnoki, Attila

    2008-01-01

    The diversity in wealth and social status is present not only among humans, but throughout the animal world. We account for this observation by generating random variables that determine the social diversity of players engaging in the prisoner’s dilemma game. Here the term social diversity is used to address extrinsic factors that determine the mapping of game payoffs to individual fitness. These factors may increase or decrease the fitness of a player depending on its location on the spatial grid. We consider different distributions of extrinsic factors that determine the social diversity of players, and find that the power-law distribution enables the best promotion of cooperation. The facilitation of the cooperative strategy relies mostly on the inhomogeneous social state of players, resulting in the formation of cooperative clusters which are ruled by socially high-ranking players that are able to prevail against the defectors even when there is a large temptation to defect. To confirm this, we also study the impact of spatially correlated social diversity and find that cooperation deteriorates as the spatial correlation length increases. Our results suggest that the distribution of wealth and social status might have played a crucial role by the evolution of cooperation amongst egoistic individuals.

  10. Social diversity promotes the emergence of cooperation in public goods games.

    PubMed

    Santos, Francisco C; Santos, Marta D; Pacheco, Jorge M

    2008-07-10

    Humans often cooperate in public goods games and situations ranging from family issues to global warming. However, evolutionary game theory predicts that the temptation to forgo the public good mostly wins over collective cooperative action, and this is often also seen in economic experiments. Here we show how social diversity provides an escape from this apparent paradox. Up to now, individuals have been treated as equivalent in all respects, in sharp contrast with real-life situations, where diversity is ubiquitous. We introduce social diversity by means of heterogeneous graphs and show that cooperation is promoted by the diversity associated with the number and size of the public goods game in which each individual participates and with the individual contribution to each such game. When social ties follow a scale-free distribution, cooperation is enhanced whenever all individuals are expected to contribute a fixed amount irrespective of the plethora of public goods games in which they engage. Our results may help to explain the emergence of cooperation in the absence of mechanisms based on individual reputation and punishment. Combining social diversity with reputation and punishment will provide instrumental clues on the self-organization of social communities and their economical implications. PMID:18615084

  11. Multi-user distribution of polarization entangled photon pairs

    SciTech Connect

    Trapateau, J.; Orieux, A.; Diamanti, E.; Zaquine, I.; Ghalbouni, J.

    2015-10-14

    We experimentally demonstrate multi-user distribution of polarization entanglement using commercial telecom wavelength division demultiplexers. The entangled photon pairs are generated from a broadband source based on spontaneous parametric down conversion in a periodically poled lithium niobate crystal using a double path setup employing a Michelson interferometer and active phase stabilisation. We test and compare demultiplexers based on various technologies and analyze the effect of their characteristics, such as losses and polarization dependence, on the quality of the distributed entanglement for three channel pairs of each demultiplexer. In all cases, we obtain a Bell inequality violation, whose value depends on the demultiplexer features. This demonstrates that entanglement can be distributed to at least three user pairs of a network from a single source. Additionally, we verify for the best demultiplexer that the violation is maintained when the pairs are distributed over a total channel attenuation corresponding to 20 km of optical fiber. These techniques are therefore suitable for resource-efficient practical implementations of entanglement-based quantum key distribution and other quantum communication network applications.

  12. Atmospheric lidar multi-user instrument system definition study

    NASA Technical Reports Server (NTRS)

    Greco, R. V. (Editor)

    1980-01-01

    A spaceborne lidar system for atmospheric studies was defined. The primary input was the Science Objectives Experiment Description and Evolutionary Flow Document. The first task of the study was to perform an experiment evolutionary analysis of the SEED. The second task was the system definition effort of the instrument system. The third task was the generation of a program plan for the hardware phase. The fourth task was the supporting studies which included a Shuttle deficiency analysis, a preliminary safety hazard analysis, the identification of long lead items, and development studies required. As a result of the study an evolutionary Lidar Multi-User Instrument System (MUIS) was defined. The MUIS occupies a full Spacelab pallet and has a weight of 1300 kg. The Lidar MUIS laser provides a 2 joule frequency doubled Nd:YAG laser that can also pump a tuneable dye laser wide frequency range and bandwidth. The MUIS includes a 1.25 meter diameter aperture Cassegrain receiver, with a moveable secondary mirror to provide precise alignment with the laser. The receiver can transmit the return signal to three single and multiple photomultiple tube detectors by use of a rotating fold mirror. It is concluded that the Lidar MUIS proceed to program implementation.

  13. Interactions between carbon sequestration and shade tree diversity in a smallholder coffee cooperative in El Salvador.

    PubMed

    Richards, Meryl Breton; Méndez, V Ernesto

    2014-04-01

    Agroforestry systems have substantial potential to conserve native biodiversity and provide ecosystem services. In particular, agroforestry systems have the potential to conserve native tree diversity and sequester carbon for climate change mitigation. However, little research has been conducted on the temporal stability of species diversity and aboveground carbon stocks in these systems or the relation between species diversity and aboveground carbon sequestration. We measured changes in shade-tree diversity and shade-tree carbon stocks in 14 plots of a 35-ha coffee cooperative over 9 years and analyzed relations between species diversity and carbon sequestration. Carbon sequestration was positively correlated with initial species richness of shade trees. Species diversity of shade trees did not change significantly over the study period, but carbon stocks increased due to tree growth. Our results show a potential for carbon sequestration and long-term biodiversity conservation in smallholder coffee agroforestry systems and illustrate the opportunity for synergies between biodiversity conservation and climate change mitigation.

  14. Multi-User Space Link Extension (SLE) System

    NASA Technical Reports Server (NTRS)

    Perkins, Toby

    2013-01-01

    The Multi-User Space (MUS) Link Extension system, a software and data system, provides Space Link Extension (SLE) users with three space data transfer services in timely, complete, and offline modes as applicable according to standards defined by the Consultative Committee for Space Data Systems (CCSDS). MUS radically reduces the schedule, cost, and risk of implementing a new SLE user system, minimizes operating costs with a lights-out approach to SLE, and is designed to require no sustaining engineering expense during its lifetime unless changes in the CCSDS SLE standards, combined with new provider implementations, force changes. No software modification to MUS needs to be made to support a new mission. Any systems engineer with Linux experience can begin testing SLE user service instances with MUS starting from a personal computer (PC) within five days. For flight operators, MUS provides a familiar-looking Web page for entering SLE configuration data received from SLE. Operators can also use the Web page to back up a space mission's entire set of up to approximately 500 SLE service instances in less than five seconds, or to restore or transfer from another system the same amount of data from a MUS backup file in about the same amount of time. Missions operate each MUS SLE service instance independently by sending it MUS directives, which are legible, plain ASCII strings. MUS directives are usually (but not necessarily) sent through a TCP-IP (Transmission Control Protocol Internet Protocol) socket from a MOC (Mission Operations Center) or POCC (Payload Operations Control Center) system, under scripted control, during "lights-out" spacecraft operation. MUS permits the flight operations team to configure independently each of its data interfaces; not only commands and telemetry, but also MUS status messages to the MOC. Interfaces can use single- or multiple-client TCP/IP server sockets, TCP/IP client sockets, temporary disk files, the system log, or standard in

  15. Dynamic instability of cooperation due to diverse activity patterns in evolutionary social dilemmas

    NASA Astrophysics Data System (ADS)

    Xia, Cheng-Yi; Meloni, Sandro; Perc, Matjaž; Moreno, Yamir

    2015-03-01

    Individuals might abstain from participating in an instance of an evolutionary game for various reasons, ranging from lack of interest to risk aversion. In order to understand the consequences of such diverse activity patterns on the evolution of cooperation, we study a weak prisoner's dilemma where each player's participation is probabilistic rather than certain. Players that do not participate get a null payoff and are unable to replicate. We show that inactivity introduces cascading failures of cooperation, which are particularly severe on scale-free networks with frequently inactive hubs. The drops in the fraction of cooperators are sudden, while the spatiotemporal reorganization of compact cooperative clusters, and thus the recovery, takes time. Nevertheless, if the activity of players is directly proportional to their degree, or if the interaction network is not strongly heterogeneous, the overall evolution of cooperation is not impaired. This is because inactivity negatively affects the potency of low-degree defectors, who are hence unable to utilize on their inherent evolutionary advantage. Between cascading failures, the fraction of cooperators is therefore higher than usual, which lastly balances out the asymmetric dynamic instabilities that emerge due to intermittent blackouts of cooperative hubs.

  16. The Fluids And Combustion Facility Combustion Integrated Rack And The Multi-User Droplet Combustion Apparatus: Microgravity Combustion Science Using Modular Multi-User Hardware

    NASA Technical Reports Server (NTRS)

    OMalley, Terence F.; Myhre, Craig A.

    2000-01-01

    The Fluids and Combustion Facility (FCF) is a multi-rack payload planned for the International Space Station (ISS) that will enable the study of fluid physics and combustion science in a microgravity environment. The Combustion Integrated Rack (CIR) is one of two International Standard Payload Racks of the FCF and is being designed primarily to support combustion science experiments. The Multi-user Droplet Combustion Apparatus (MDCA) is a multi-user apparatus designed to accommodate four different droplet combustion science experiments and is the first payload for CIR. The CIR will function independently until the later launch of the Fluids Integrated Rack component of the FCF. This paper provides an overview of the capabilities and the development status of the CIR and MDCA.

  17. Sum-Rate Evaluation of Multi-User MIMO-Relay Channel

    NASA Astrophysics Data System (ADS)

    Sun, Huan; Meng, Sheng; Wang, Yan; You, Xiaohu

    In this paper, the multi-user multiple-input multiple-output (MU-MIMO) relay channel is investigated, where the source node provides multi-beams to multi-users via a multi-antenna relay node. In this scenario, linear processing matrix at the relay node is designed around block diagonal (BD) scheme to improve the system sum-rate. Compared with the traditional linear processing matrix with zero-forcing (ZF) scheme at the relay node, the proposed matrix based on BD scheme can not only eliminate the multi-user interference to the same extent as the ZF scheme, but also realize optimal power allocation at the relay node. Numerical simulations demonstrate the BD scheme outperforms the ZF scheme and can significantly improve the sum-rate performance.

  18. Interactions between carbon sequestration and shade tree diversity in a smallholder coffee cooperative in El Salvador.

    PubMed

    Richards, Meryl Breton; Méndez, V Ernesto

    2014-04-01

    Agroforestry systems have substantial potential to conserve native biodiversity and provide ecosystem services. In particular, agroforestry systems have the potential to conserve native tree diversity and sequester carbon for climate change mitigation. However, little research has been conducted on the temporal stability of species diversity and aboveground carbon stocks in these systems or the relation between species diversity and aboveground carbon sequestration. We measured changes in shade-tree diversity and shade-tree carbon stocks in 14 plots of a 35-ha coffee cooperative over 9 years and analyzed relations between species diversity and carbon sequestration. Carbon sequestration was positively correlated with initial species richness of shade trees. Species diversity of shade trees did not change significantly over the study period, but carbon stocks increased due to tree growth. Our results show a potential for carbon sequestration and long-term biodiversity conservation in smallholder coffee agroforestry systems and illustrate the opportunity for synergies between biodiversity conservation and climate change mitigation. PMID:24283921

  19. Multi-user cognitive radio network resource allocation based on the adaptive niche immune genetic algorithm

    NASA Astrophysics Data System (ADS)

    Zu, Yun-Xiao; Zhou, Jie

    2012-01-01

    Multi-user cognitive radio network resource allocation based on the adaptive niche immune genetic algorithm is proposed, and a fitness function is provided. Simulations are conducted using the adaptive niche immune genetic algorithm, the simulated annealing algorithm, the quantum genetic algorithm and the simple genetic algorithm, respectively. The results show that the adaptive niche immune genetic algorithm performs better than the other three algorithms in terms of the multi-user cognitive radio network resource allocation, and has quick convergence speed and strong global searching capability, which effectively reduces the system power consumption and bit error rate.

  20. Teacher Perceptions of Learning Affordances of Multi-User Virtual Environments

    ERIC Educational Resources Information Center

    Gamage, Vimani; Tretiakov, Alexei; Crump, Barbara

    2011-01-01

    While the affordances of multi-user virtual environments (MUVEs) for teaching and learning are a subject of numerous experience reports, there is little research on educators' perceptions of various MUVE affordances claimed in the literature. We investigate the educators' perceptions of claimed MUVE affordances for learning by conducting in-depth…

  1. Exploring the Use of Individualized, Reflective Guidance in an Educational Multi-User Virtual Environment

    ERIC Educational Resources Information Center

    Nelson, Brian C.

    2007-01-01

    This study examines the patterns of use and potential impact of individualized, reflective guidance in an educational Multi-User Virtual Environment (MUVE). A guidance system embedded within a MUVE-based scientific inquiry curriculum was implemented with a sample of middle school students in an exploratory study investigating (a) whether access to…

  2. Exploring Embedded Guidance and Self-Efficacy in Educational Multi-User Virtual Environments

    ERIC Educational Resources Information Center

    Nelson, Brian C.; Ketelhut, Diane Jass

    2008-01-01

    In this paper, we present the results of an exploratory study into the relationship between student self-efficacy and guidance use in a Multi-User Virtual Environment (MUVE) science curriculum project. We describe findings from a sample of middle school science students on the combined impact on learning of student self-efficacy in scientific…

  3. Multi-User Virtual Environments for Learning: Experience and Technology Design

    ERIC Educational Resources Information Center

    Di Blas, N.; Bucciero, A.; Mainetti, L.; Paolini, P.

    2012-01-01

    Multi-User Virtual Environments (MUVEs) are often used to support learning in formal and informal educational contexts. A technology-based educational experience consists of several elements: content, syllabus, roles, sequence of activities, assignments, assessment procedures, etc. that must be aligned with the affordances of the technologies to…

  4. Civic Participation among Seventh-Grade Social Studies Students in Multi-User Virtual Environments

    ERIC Educational Resources Information Center

    Zieger, Laura; Farber, Matthew

    2012-01-01

    Technological advances on the Internet now enable students to develop participation skills in virtual worlds. Similar to controlling a character in a video game, multi-user virtual environments, or MUVEs, allow participants to interact with others in synchronous, online settings. The authors of this study created a link between MUVEs and…

  5. Teacher Candidates' Views of a Multi-User Virtual Environment (MUVE)

    ERIC Educational Resources Information Center

    Sardone, Nancy B.; Devlin-Scherer, Roberta

    2008-01-01

    Multi-user virtual environments (MUVEs) are new to formal educational settings as teaching and learning tools but are growing in popularity. MUVEs simulate real-world problems. They have an ability to reach students in ways that are familiar as they resemble videogames where players assume roles, work in teams, and gather data. MUVEs include…

  6. Language Learning in Multi-User Virtual Environments: Using the Enter-the-Story Teaching Method

    ERIC Educational Resources Information Center

    Wong, Yin-Mei; Tan, Seng-Chee

    2009-01-01

    The authors propose using the Enter-the-Story teaching method for language learning in Multi-User Virtual Environments (MUVEs). A MUVE's immersive story-world imbued with rich cultural artifacts provides an appealing environment for young learners to learn a language by taking on roles in a story and describing their imaginative experience in the…

  7. From Multi-User Virtual Environment to 3D Virtual Learning Environment

    ERIC Educational Resources Information Center

    Livingstone, Daniel; Kemp, Jeremy; Edgar, Edmund

    2008-01-01

    While digital virtual worlds have been used in education for a number of years, advances in the capabilities and spread of technology have fed a recent boom in interest in massively multi-user 3D virtual worlds for entertainment, and this in turn has led to a surge of interest in their educational applications. In this paper we briefly review the…

  8. Socialisation for Learning at a Distance in a 3-D Multi-User Virtual Environment

    ERIC Educational Resources Information Center

    Edirisingha, Palitha; Nie, Ming; Pluciennik, Mark; Young, Ruth

    2009-01-01

    This paper reports findings of a pilot study that examined the pedagogical potential of "Second Life" (SL), a popular three-dimensional multi-user virtual environment (3-D MUVE) developed by the Linden Lab. The study is part of a 1-year research and development project titled "Modelling of Secondlife Environments" (http://www.le.ac.uk/moose)…

  9. Preservice Teachers Experience Reading Response Pedagogy in a Multi-User Virtual Environment

    ERIC Educational Resources Information Center

    Dooley, Caitlin McMunn; Calandra, Brendan; Harmon, Stephen

    2014-01-01

    This qualitative case study describes how 18 preservice teachers learned to nurture literary meaning-making via activities based on Louise Rosenblatt's Reader Response Theory within a multi-user virtual environment (MUVE). Participants re-created and responded to scenes from selected works of children's literature in Second Life as a way to…

  10. Evaluation of Learning Efficiency and Efficacy in a Multi-User Virtual Environment

    ERIC Educational Resources Information Center

    Hearrington, Doug

    2011-01-01

    This study evaluated the multi-user virtual environment (MUVE) known as Second Life, integrated with Moodle and SLOODLE technologies, as an exploratory course delivery platform and for its ability to enable teachers to meet elements of NETS.T. Graduate student participants (N = 17) interacted, constructed simulated schools, and attended classes…

  11. Design and Implementation of a 3D Multi-User Virtual World for Language Learning

    ERIC Educational Resources Information Center

    Ibanez, Maria Blanca; Garcia, Jose Jesus; Galan, Sergio; Maroto, David; Morillo, Diego; Kloos, Carlos Delgado

    2011-01-01

    The best way to learn is by having a good teacher and the best language learning takes place when the learner is immersed in an environment where the language is natively spoken. 3D multi-user virtual worlds have been claimed to be useful for learning, and the field of exploiting them for education is becoming more and more active thanks to the…

  12. A Multi-User Virtual Environment for Building and Assessing Higher Order Inquiry Skills in Science

    ERIC Educational Resources Information Center

    Ketelhut, Diane Jass; Nelson, Brian C.; Clarke, Jody; Dede, Chris

    2010-01-01

    This study investigated novel pedagogies for helping teachers infuse inquiry into a standards-based science curriculum. Using a multi-user virtual environment (MUVE) as a pedagogical vehicle, teams of middle-school students collaboratively solved problems around disease in a virtual town called River City. The students interacted with "avatars" of…

  13. Global cooperation among diverse organizations to reduce illegal fishing in the Southern Ocean.

    PubMed

    Osterblom, Henrik; Bodin, Orjan

    2012-08-01

    Illegal, unreported, and unregulated (IUU) fishing is prevalent globally and has detrimental effects on commercial fish stocks and nontarget species. Effective monitoring and enforcement aimed at reducing the level of IUU fishing in extensive, remote ocean fisheries requires international collaboration. Changes in trade and vessel activities further complicate enforcement. We used a web-based survey of governmental and nongovernmental organizations engaged in reducing IUU fishing in the Southern Ocean to collect information on interorganizational collaborations. We used social-network analyses to examine the nature of collaborations among the identified 117 organizations engaged in reducing IUU fishing. International collaboration improved the ability to control and manage harvest of commercially important toothfish (Dissostichus spp.) stocks and reduced bycatch of albatrosses (Diomedeidae) and petrels (Procellariidae) in longlines of IUU fishing vessels. The diverse group of surveyed organizations cooperated frequently, thereby making a wide range of resources available for improved detection of suspected IUU vessels and trade flows, cooperation aimed at prosecuting suspected offenders or developing new policy measures. Our results suggest the importance of a central agency for coordination and for maintaining commonly agreed-upon protocols for communication that facilities collaboration. Despite their differences, the surveyed organizations have developed common perceptions about key problems associated with IUU fishing. This has likely contributed to a sustained willingness to invest in collaborations. Our results show that successful international environmental governance can be accomplished through interorganizational collaborations. Such cooperation requires trust, continuous funding, and incentives for actors to participate.

  14. Global cooperation among diverse organizations to reduce illegal fishing in the Southern Ocean.

    PubMed

    Osterblom, Henrik; Bodin, Orjan

    2012-08-01

    Illegal, unreported, and unregulated (IUU) fishing is prevalent globally and has detrimental effects on commercial fish stocks and nontarget species. Effective monitoring and enforcement aimed at reducing the level of IUU fishing in extensive, remote ocean fisheries requires international collaboration. Changes in trade and vessel activities further complicate enforcement. We used a web-based survey of governmental and nongovernmental organizations engaged in reducing IUU fishing in the Southern Ocean to collect information on interorganizational collaborations. We used social-network analyses to examine the nature of collaborations among the identified 117 organizations engaged in reducing IUU fishing. International collaboration improved the ability to control and manage harvest of commercially important toothfish (Dissostichus spp.) stocks and reduced bycatch of albatrosses (Diomedeidae) and petrels (Procellariidae) in longlines of IUU fishing vessels. The diverse group of surveyed organizations cooperated frequently, thereby making a wide range of resources available for improved detection of suspected IUU vessels and trade flows, cooperation aimed at prosecuting suspected offenders or developing new policy measures. Our results suggest the importance of a central agency for coordination and for maintaining commonly agreed-upon protocols for communication that facilities collaboration. Despite their differences, the surveyed organizations have developed common perceptions about key problems associated with IUU fishing. This has likely contributed to a sustained willingness to invest in collaborations. Our results show that successful international environmental governance can be accomplished through interorganizational collaborations. Such cooperation requires trust, continuous funding, and incentives for actors to participate. PMID:22624623

  15. Service description of communication systems supporting multi-media multi-user applications

    NASA Astrophysics Data System (ADS)

    Heijenk, G. J.; Hou, X.; Niemegeers, I. G.

    The paper presents a service description of communication systems supporting multi-media multi-user applications. In particular, it focuses on service elements related to the call control. The service description specifies the functional behavior of the communication system as a whole. It can be used as a common reference in the next design stages, e.g., in the protocol design and implementation of both Customer Premises Networks and public telecommunication networks. After discussing the requirements of multi-media multi-user applications, a call model is presented. This model creates an abstract view of those aspects of the call relevant for the design and helps us in structuring the service. Only those service elements of a communication system that are related to the call establishment, modification and termination are fully specified by describing service primitives, their parameters and temporal ordering constraints.

  16. Positively Frequency-Dependent Interference Competition Maintains Diversity and Pervades a Natural Population of Cooperative Microbes.

    PubMed

    Rendueles, Olaya; Amherd, Michaela; Velicer, Gregory J

    2015-06-29

    Positively frequency-dependent selection is predicted from theory to promote diversity in patchily structured populations and communities, but empirical support for this prediction has been lacking. Here, we investigate frequency-dependent selection among isolates from a local natural population of the highly social bacterium Myxococcus xanthus. Upon starvation, closely related cells of M. xanthus cooperate to construct multicellular fruiting bodies, yet recently diverged genotypes co-residing in a local soil population often antagonize one another during fruiting-body development in mixed groups. In the experiments reported here, both fitness per se and strong forms of interference competition exhibit pervasive and strong positive frequency dependence (PFD) among many isolates from a centimeter-scale soil population of M. xanthus. All strains that compete poorly at intermediate frequency are shown to be competitively dominant at high frequency in most genotype pairings during both growth and development, and strongly so. Interference competition is often lethal and appears to be contact dependent rather than mediated by diffusible compounds. Finally, we experimentally demonstrate that positively frequency-dependent selection maintains diversity when genotype frequencies vary patchily in structured populations. These results suggest that PFD contributes to the high levels of local diversity found among M. xanthus social groups in natural soil populations by reinforcing social barriers to cross-territory invasion and thereby also promotes high within-group relatedness. More broadly, our results suggest that potential roles of PFD in maintaining patchily distributed diversity should be investigated more extensively in other species. PMID:26051889

  17. The Fluids and Combustion Facility Combustion Integrated Rack and The Multi-User Droplet Combustion Apparatus: Microgravity Combustion Science Using A Modular Multi-User Hardware

    NASA Astrophysics Data System (ADS)

    O'Malley, T. F.; Myhre, C. A.

    2002-01-01

    The Fluids and Combustion Facility (FCF) is a multi-rack payload planned for the International Space Station that will enable the study of fluid physics and combustion science in a microgravity environment. The Combustion Integrated Rack (CIR) is one of two International Standard Payload Racks of the FCF and is being designed primarily to support combustion science experiments. It is currently in the Flight Unit Build phase. The Multi-user Droplet Combustion Apparatus (MDCA) is a multi-user facility designed to accommodate four different droplet combustion science experiments and is the first payload for CIR. MDCA is currently in the Engineering Model build phase. Launch of the CIR and MDCA is planned for 2004. The CIR will function independently until the later launch of the Fluids Integrated Rack component of the FCF. This paper provides an overview of the capabilities and the development status of the CIR and MDCA. The CIR will contain the hardware and software required to support combustion experiments in space. It will contain an optics bench, combustion chamber, fuel oxidizer and management assembly, exhaust vent system, diagnostic cameras, power, environment control system, command and data management system, and a passive rack isolation system. Additional hardware will be installed in the chamber and on the optics bench that is customized for each science investigation. The chamber insert may provide the sample holder, small ignition source, and small diagnostics such as thermocouples and radiometers. The combustion experiments that may be conducted in the FCF include, but are not limited to, the study of laminar flames, reaction kinetics, droplet and spray combustion, flame spread, fire and fire suppressants, condensed phase organic fuel combustion, turbulent combustion, soot and polycyclic aromatic hydrocarbons, and materials synthesis. It is expected that the facility will provide most of the hardware, with a small amount of unique hardware developed for

  18. The right view from the wrong location: depth perception in stereoscopic multi-user virtual environments.

    PubMed

    Pollock, Brice; Burton, Melissa; Kelly, Jonathan W; Gilbert, Stephen; Winer, Eliot

    2012-04-01

    Stereoscopic depth cues improve depth perception and increase immersion within virtual environments (VEs). However, improper display of these cues can distort perceived distances and directions. Consider a multi-user VE, where all users view identical stereoscopic images regardless of physical location. In this scenario, cues are typically customized for one "leader" equipped with a head-tracking device. This user stands at the center of projection (CoP) and all other users ("followers") view the scene from other locations and receive improper depth cues. This paper examines perceived depth distortion when viewing stereoscopic VEs from follower perspectives and the impact of these distortions on collaborative spatial judgments. Pairs of participants made collaborative depth judgments of virtual shapes viewed from the CoP or after displacement forward or backward. Forward and backward displacement caused perceived depth compression and expansion, respectively, with greater compression than expansion. Furthermore, distortion was less than predicted by a ray-intersection model of stereo geometry. Collaboration times were significantly longer when participants stood at different locations compared to the same location, and increased with greater perceived depth discrepancy between the two viewing locations. These findings advance our understanding of spatial distortions in multi-user VEs, and suggest a strategy for reducing distortion.

  19. Advancing MEMS Technology Usage through the MUMPS (Multi-User MEMS Processes) Program

    NASA Technical Reports Server (NTRS)

    Koester, D. A.; Markus, K. W.; Dhuler, V.; Mahadevan, R.; Cowen, A.

    1995-01-01

    In order to help provide access to advanced micro-electro-mechanical systems (MEMS) technologies and lower the barriers for both industry and academia, the Microelectronic Center of North Carolina (MCNC) and ARPA have developed a program which provides users with access to both MEMS processes and advanced electronic integration techniques. The four distinct aspects of this program, the multi-user MEMS processes (MUMP's), the consolidated micro-mechanical element library, smart MEMS, and the MEMS technology network are described in this paper. MUMP's is an ARPA-supported program created to provide inexpensive access to MEMS technology in a multi-user environment. It is both a proof-of-concept and educational tool that aids in the development of MEMS in the domestic community. MUMP's technologies currently include a 3-layer poly-silicon surface micromachining process and LIGA (lithography, electroforming, and injection molding) processes that provide reasonable design flexibility within set guidelines. The consolidated micromechanical element library (CaMEL) is a library of active and passive MEMS structures that can be downloaded by the MEMS community via the internet. Smart MEMS is the development of advanced electronics integration techniques for MEMS through the application of flip chip technology. The MEMS technology network (TechNet) is a menu of standard substrates and MEMS fabrication processes that can be purchased and combined to create unique process flows. TechNet provides the MEMS community greater flexibility and enhanced technology accessibility.

  20. Distributed Compressive CSIT Estimation and Feedback for FDD Multi-User Massive MIMO Systems

    NASA Astrophysics Data System (ADS)

    Rao, Xiongbin; Lau, Vincent K. N.

    2014-06-01

    To fully utilize the spatial multiplexing gains or array gains of massive MIMO, the channel state information must be obtained at the transmitter side (CSIT). However, conventional CSIT estimation approaches are not suitable for FDD massive MIMO systems because of the overwhelming training and feedback overhead. In this paper, we consider multi-user massive MIMO systems and deploy the compressive sensing (CS) technique to reduce the training as well as the feedback overhead in the CSIT estimation. The multi-user massive MIMO systems exhibits a hidden joint sparsity structure in the user channel matrices due to the shared local scatterers in the physical propagation environment. As such, instead of naively applying the conventional CS to the CSIT estimation, we propose a distributed compressive CSIT estimation scheme so that the compressed measurements are observed at the users locally, while the CSIT recovery is performed at the base station jointly. A joint orthogonal matching pursuit recovery algorithm is proposed to perform the CSIT recovery, with the capability of exploiting the hidden joint sparsity in the user channel matrices. We analyze the obtained CSIT quality in terms of the normalized mean absolute error, and through the closed-form expressions, we obtain simple insights into how the joint channel sparsity can be exploited to improve the CSIT recovery performance.

  1. Diverse roles of the reduced learning ability of players in the evolution of cooperation

    NASA Astrophysics Data System (ADS)

    Wu, Zhi-Xi; Rong, Zhihai; Chen, Michael Z. Q.

    2015-05-01

    Individual heterogeneity in the reproductive rate is found to play an important role in the emergence and persistence of cooperation. Most of the existing literature focused mainly on the enhancement of cooperation by the introduction of inhomogeneous teaching capability of the individuals. It is far from clear how the heterogeneous learning ability of the individuals affects the evolution of cooperation. To fill this research gap, we make comparative studies of the evolutionary spatial prisoner's dilemma game with reduced learning or teaching ability of the players, under both synchronous and asynchronous strategy updating schemes. By carrying out extensive computer simulations, we show that cooperation can always be facilitated if the inhomogeneous teaching ability of the players is considered, irrespectively of the strategy updating manner. By contrast, cooperation is promoted (inhibited) in the case of synchronous (asynchronous) strategy updating, if heterogeneous learning ability is considered, which is attributed to the reduced ability of cooperators to expand their domains.

  2. Specification and Verification of Multi-user Data-Driven Web Applications

    NASA Astrophysics Data System (ADS)

    Marcus, Monica

    We propose a model for multi-user data-driven communicating Web applications. An arbitrary number of users may access the application concurrently through Web sites and Web services. A Web service may have an arbitrary number of instances. The interaction between users and Web application is data-driven. Synchronous communication is done by shared access to the database and global application state. Private information may be stored in a local state. Asynchronous communication is done by message passing. A version of first-order linear time temporal logic (LTL-FO) is proposed to express behavioral properties of Web applications. The model is used to formally specify a significant fragment of an e-business application. Some of its desirable properties are expressed as LTL-FO formulas. We study a decision problem, namely whether the model satisfies an LTL-FO formula. We show the undecidability of the unrestricted verification problem and discuss some restrictions that ensure decidability.

  3. Genetic algorithm approach for adaptive power and subcarrier allocation in multi-user OFDM systems

    NASA Astrophysics Data System (ADS)

    Reddy, Y. B.; Naraghi-Pour, Mort

    2007-04-01

    In this paper, a novel genetic algorithm application is proposed for adaptive power and subcarrier allocation in multi-user Orthogonal Frequency Division Multiplexing (OFDM) systems. To test the application, a simple genetic algorithm was implemented in MATLAB language. With the goal of minimizing the overall transmit power while ensuring the fulfillment of each user's rate and bit error rate (BER) requirements, the proposed algorithm acquires the needed allocation through genetic search. The simulations were tested for BER 0.1 to 0.00001, data rate of 256 bit per OFDM block and chromosome length of 128. The results show that genetic algorithm outperforms the results in [3] in subcarrier allocation. The convergence of GA model with 8 users and 128 subcarriers performs better in power requirement compared to that in [4] but converges more slowly.

  4. Near-Optimal Multi-user Greedy Bit-Loading for Digital Subscriber Lines

    NASA Astrophysics Data System (ADS)

    McKinley, Alastair; Marshall, Alan

    This work presents a new algorithm for Dynamic Spectrum Management (DSM) in Digital Subscriber Lines. Previous approaches have achieved high performance by attempting to directly solve or approximate the multiuser spectrum optimisation problem. These methods suffer from a high or intractable computational complexity for even a moderate number of DSL lines. A new method is proposed which is a heuristic extension of the single user greedy algorithm applied to the multi-user case. The new algorithm incorporates a novel cost function that penalises crosstalk as well as considering the usefulness of a tone. Previous work has proved the performance of the new algorithm in simple 2-user scenarios. In this work we present new results which demonstrate the performance of the algorithm in larger DSL bundles. Simulation results are presented and it is shown that the new method achieves results within a few percent of the optimal solution for these scenarios.

  5. Multi-user quantum key distribution with collective eavesdropping detection over collective-noise channels

    NASA Astrophysics Data System (ADS)

    Huang, Wei; Wen, Qiao-Yan; Liu, Bin; Gao, Fei

    2015-07-01

    A multi-user quantum key distribution protocol is proposed with single particles and the collective eavesdropping detection strategy on a star network. By utilizing this protocol, any two users of the network can accomplish quantum key distribution with the help of a serving center. Due to the utilization of the collective eavesdropping detection strategy, the users of the protocol just need to have the ability of performing certain unitary operations. Furthermore, we present three fault-tolerant versions of the proposed protocol, which can combat with the errors over different collective-noise channels. The security of all the proposed protocols is guaranteed by the theorems on quantum operation discrimination. Project supported by the National Natural Science Foundation of China (Grant Nos. 61272057, 61170270, and 61309029), Beijing Higher Education Young Elite Teacher Project, China (Grant Nos. YETP0475 and YETP0477), and BUPT Excellent Ph.D. Students Foundation, China (Grant No. CX201441).

  6. Interaction Design and Usability of Learning Spaces in 3D Multi-user Virtual Worlds

    NASA Astrophysics Data System (ADS)

    Minocha, Shailey; Reeves, Ahmad John

    Three-dimensional virtual worlds are multimedia, simulated environments, often managed over the Web, which users can 'inhabit' and interact via their own graphical, self-representations known as 'avatars'. 3D virtual worlds are being used in many applications: education/training, gaming, social networking, marketing and commerce. Second Life is the most widely used 3D virtual world in education. However, problems associated with usability, navigation and way finding in 3D virtual worlds may impact on student learning and engagement. Based on empirical investigations of learning spaces in Second Life, this paper presents design guidelines to improve the usability and ease of navigation in 3D spaces. Methods of data collection include semi-structured interviews with Second Life students, educators and designers. The findings have revealed that design principles from the fields of urban planning, Human- Computer Interaction, Web usability, geography and psychology can influence the design of spaces in 3D multi-user virtual environments.

  7. The theory research of multi-user quantum access network with Measurement Device Independent quantum key distribution

    NASA Astrophysics Data System (ADS)

    Ji, Yi-Ming; Li, Yun-Xia; Shi, Lei; Meng, Wen; Cui, Shu-Min; Xu, Zhen-Yu

    2015-10-01

    Quantum access network can't guarantee the absolute security of multi-user detector and eavesdropper can get access to key information through time-shift attack and other ways. Measurement-device-independent quantum key distribution is immune from all the detection attacks, and accomplishes the safe sharing of quantum key. In this paper, that Measurement-device-independent quantum key distribution is used in the application of multi-user quantum access to the network is on the research. By adopting time-division multiplexing technology to achieve the sharing of multiuser detector, the system structure is simplified and the security of quantum key sharing is acquired.

  8. Staffing Strategies for a More Diverse Workforce: Case Examples from Cornell Cooperative Extension.

    ERIC Educational Resources Information Center

    Grogan, Soneeta; Eshelman, Barbara

    1998-01-01

    Organizational culture change is required to address diversity. The first step is changing behavior regarding inclusive staff recruitment and retention strategies. Preparing the workplace to support staff from diverse backgrounds is essential. (SK)

  9. Local packing modulates diversity of iron pathways and cooperative behavior in eukaryotic and prokaryotic ferritins.

    PubMed

    Ruvinsky, Anatoly M; Vakser, Ilya A; Rivera, Mario

    2014-03-21

    Ferritin-like molecules show a remarkable combination of the evolutionary conserved activity of iron uptake and release that engage different pores in the conserved ferritin shell. It was hypothesized that pore selection and iron traffic depend on dynamic allostery with no conformational changes in the backbone. In this study, we detect the allosteric networks in Pseudomonas aeruginosa bacterioferritin (BfrB), bacterial ferritin (FtnA), and bullfrog M and L ferritins (Ftns) by a network-weaving algorithm (NWA) that passes threads of an allosteric network through highly correlated residues using hierarchical clustering. The residue-residue correlations are calculated in the packing-on elastic network model that introduces atom packing into the common packing-off model. Applying NWA revealed that each of the molecules has an extended allosteric network mostly buried inside the ferritin shell. The structure of the networks is consistent with experimental observations of iron transport: The allosteric networks in BfrB and FtnA connect the ferroxidase center with the 4-fold pores and B-pores, leaving the 3-fold pores unengaged. In contrast, the allosteric network directly links the 3-fold pores with the 4-fold pores in M and L Ftns. The majority of the network residues are either on the inner surface or buried inside the subunit fold or at the subunit interfaces. We hypothesize that the ferritin structures evolved in a way to limit the influence of functionally unrelated events in the cytoplasm on the allosteric network to maintain stability of the translocation mechanisms. We showed that the residue-residue correlations and the resultant long-range cooperativity depend on the ferritin shell packing, which, in turn, depends on protein sequence composition. Switching from the packing-on to the packing-off model reduces correlations by 35%-38% so that no allosteric network can be found. The influence of the side-chain packing on the allosteric networks explains the

  10. Local packing modulates diversity of iron pathways and cooperative behavior in eukaryotic and prokaryotic ferritins

    SciTech Connect

    Ruvinsky, Anatoly M.; Vakser, Ilya A.; Rivera, Mario

    2014-03-21

    Ferritin-like molecules show a remarkable combination of the evolutionary conserved activity of iron uptake and release that engage different pores in the conserved ferritin shell. It was hypothesized that pore selection and iron traffic depend on dynamic allostery with no conformational changes in the backbone. In this study, we detect the allosteric networks in Pseudomonas aeruginosa bacterioferritin (BfrB), bacterial ferritin (FtnA), and bullfrog M and L ferritins (Ftns) by a network-weaving algorithm (NWA) that passes threads of an allosteric network through highly correlated residues using hierarchical clustering. The residue-residue correlations are calculated in the packing-on elastic network model that introduces atom packing into the common packing-off model. Applying NWA revealed that each of the molecules has an extended allosteric network mostly buried inside the ferritin shell. The structure of the networks is consistent with experimental observations of iron transport: The allosteric networks in BfrB and FtnA connect the ferroxidase center with the 4-fold pores and B-pores, leaving the 3-fold pores unengaged. In contrast, the allosteric network directly links the 3-fold pores with the 4-fold pores in M and L Ftns. The majority of the network residues are either on the inner surface or buried inside the subunit fold or at the subunit interfaces. We hypothesize that the ferritin structures evolved in a way to limit the influence of functionally unrelated events in the cytoplasm on the allosteric network to maintain stability of the translocation mechanisms. We showed that the residue-residue correlations and the resultant long-range cooperativity depend on the ferritin shell packing, which, in turn, depends on protein sequence composition. Switching from the packing-on to the packing-off model reduces correlations by 35%–38% so that no allosteric network can be found. The influence of the side-chain packing on the allosteric networks explains the

  11. Diverse strategy-learning styles promote cooperation in evolutionary spatial prisoner's dilemma game

    NASA Astrophysics Data System (ADS)

    Liu, Run-Ran; Jia, Chun-Xiao; Rong, Zhihai

    2015-11-01

    Observational learning and practice learning are two important learning styles and play important roles in our information acquisition. In this paper, we study a spacial evolutionary prisoner's dilemma game, where players can choose the observational learning rule or the practice learning rule when updating their strategies. In the proposed model, we use a parameter p controlling the preference of players choosing the observational learning rule, and found that there exists an optimal value of p leading to the highest cooperation level, which indicates that the cooperation can be promoted by these two learning rules collaboratively and one single learning rule is not favor the promotion of cooperation. By analysing the dynamical behavior of the system, we find that the observational learning rule can make the players residing on cooperative clusters more easily realize the bad sequence of mutual defection. However, a too high observational learning probability suppresses the players to form compact cooperative clusters. Our results highlight the importance of a strategy-updating rule, more importantly, the observational learning rule in the evolutionary cooperation.

  12. Deciding to Cooperate in Northern Ghana: Trust as an Evolutionary Constraint Across Cultural Diversity.

    PubMed

    Acedo-Carmona, Cristina; Gomila, Antoni

    2015-11-27

    The upper-east and northern regions of Ghana offers a unique opportunity to study the influence of evolutionary social dynamics in making cooperation possible, despite cultural differences. These regions are occupied by several distinct ethnic groups, in interaction, such as the Kussasi, Mamprusi, Bimoba, Konkomba, and Fulani. We will report our fieldwork related to how cooperation takes places there, both within each group and among people from the different groups. Methods included personal networks of cooperation (ego networks), interviews and analysis of group contexts. The most important result is that, while each ethnic group may differ in terms of family and clan structure, a similar pattern can be found in all of them, of cooperation structured around small groups of trust-based close relationships. The study suggests that habitual decisions about cooperation are not strategic or self-interested, but instead are based on unconscious processes sustained by the emotional bonds of trust. These kind of emotional bonds are claimed to be relevant from an evolutionary point of view.

  13. An Architecture For Shared Multi-User Client Rendering Of Massive Geodatasets

    NASA Astrophysics Data System (ADS)

    Al-Naser, A.; Brooke, J.; Rasheed, M.; Irving, D. H.

    2012-12-01

    We are developing a novel data-centric visualization architecture to allow interactive exploration of geophysical data. Our method allows multiple users to collaborate in a lightweight, loosely-coupled and highly scalable environment. We choose 3D seismic data for our case study. Existing visualization solutions for data exploratory tasks are mainly application-centric rather than data-centric. They typically store large datasets on users' local machines for fast access. Additionally, data objects that are the focus of study, e.g. seismic surveys and interpreted geological features, are managed as objects that are independent of the primary data. Thus multi-user collaborations where different users visually share their geological interpretations are handled inefficiently since objects from each interpretation are stored as independent discrete objects. These objects may be stored separately from the primary data, e.g. on local disks, ensuring a coherent multi-user view is difficult. Our visual analytic method places a central data structure built on a Massively Parallel Processing (MPP) relational database at the heart of the visualization architecture. This structure allows us to develop the following efficient methods for data retrieval and display: -global hashing for spatial reference on all datasets -interpretation tagging which accumulate user interpretation into the database -multi-user concurrent access allowing parallel multi-threading queries In our data structure, data elements are indexed on their geolocations by a hashing algorithm. The hashing algorithm determines the location of the required row through hashing functions without a construction or any storage complexity. This is unlike other conventional indexing algorithms such as bitmapping or tree-based methods where construction and storage (of the index table) complexity varies between O(n) and O(n log n) where n is the size of the dataset. Also, we replace the geometric objects formed as a

  14. Inspiring Equal Contribution and Opportunity in a 3D Multi-User Virtual Environment: Bringing Together Men Gamers and Women Non-Gamers in Second Life[R

    ERIC Educational Resources Information Center

    deNoyelles, Aimee; Seo, Kay Kyeong-Ju

    2012-01-01

    A 3D multi-user virtual environment holds promise to support and enhance student online learning communities due to its ability to promote global synchronous interaction and collaboration, rich multisensory experience and expression, and elaborate design capabilities. Second Life[R], a multi-user virtual environment intended for adult users 18 and…

  15. Disorder transitions and conformational diversity cooperatively modulate biological function in proteins.

    PubMed

    Zea, Diego Javier; Monzon, Alexander Miguel; Gonzalez, Claudia; Fornasari, María Silvina; Tosatto, Silvio C E; Parisi, Gustavo

    2016-06-01

    Structural differences between conformers sustain protein biological function. Here, we studied in a large dataset of 745 intrinsically disordered proteins, how ordered-disordered transitions modulate structural differences between conformers as derived from crystallographic data. We found that almost 50% of the proteins studied show no transitions and have low conformational diversity while the rest show transitions and a higher conformational diversity. In this last subset, 60% of the proteins become more ordered after ligand binding, while 40% more disordered. As protein conformational diversity is inherently connected with protein function our analysis suggests differences in structure-function relationships related to order-disorder transitions.

  16. Promotion of cooperation due to diversity of players in the spatial public goods game with increasing neighborhood size

    NASA Astrophysics Data System (ADS)

    Zhu, Cheng-jie; Sun, Shi-wen; Wang, Li; Ding, Shuai; Wang, Juan; Xia, Cheng-yi

    2014-07-01

    It is well-known that individual diversity is a typical feature within the collective population. To model this kind of characteristics, we propose an evolutionary model of public goods game with two types of players (named as A and B), where players are located on the sites of a square lattice satisfying the periodic boundary conditions. The evolution of the strategy distribution is governed by iterated strategy adoption from a randomly selected neighbor with a probability, which not only depends on the payoff difference between players, but also on the type of the neighbor. For B-type agents, we pose a pre-factor (0cooperators characterizing the promotion of cooperation. Current findings are of utmost importance for us to understand the evolution of cooperation under many real-world circumstances, such as the natural, biological, economic and even social systems.

  17. Exploring the Use of Individualized, Reflective Guidance In an Educational Multi-User Virtual Environment

    NASA Astrophysics Data System (ADS)

    Nelson, Brian C.

    2007-02-01

    This study examines the patterns of use and potential impact of individualized, reflective guidance in an educational Multi-User Virtual Environment (MUVE). A guidance system embedded within a MUVE-based scientific inquiry curriculum was implemented with a sample of middle school students in an exploratory study investigating (a) whether access to the guidance system was associated with improved learning, (b) whether students viewing more guidance messages saw greater improvement on content tests than those viewing less, and (c) whether there were any differences in guidance use among boys and girls. Initial experimental findings showed that basic access to individualized guidance used with a MUVE had no measurable impact on learning. However, post-hoc exploratory analyses indicated that increased use of the system among those with access to it was positively associated with content test score gains. In addition, differences were found in overall learning outcomes by gender and in patterns of guidance use by boys and girls, with girls outperforming boys across a spectrum of guidance system use. Based on these exploratory findings, the paper suggests design guidelines for the development of guidance systems embedded in MUVEs and outlines directions for further research.

  18. Multi-user satellite communications system using an innovative compressive receiver

    NASA Technical Reports Server (NTRS)

    Staples, Edward J.

    1992-01-01

    There is a need for an onboard simultaneous multi-channel demodulation system for a satellite communications system. Studies indicate that Convolve Multiply Convolve (CMC) filtering with surface acoustic wave (SAW) dispersive delay lines will eliminate the necessity of onboard satellite channelized filters of complex fourier transform processors. The reason for choosing the CMC technique is its ability to perform Fourier transformations in a shorter time with less space and power consumption than digital Fourier transform processors. Each ground terminal in this multi-users communications system is remotely located and operates independently; hence, a method of synchronizing the transmission of these users is presented which utilizes the existing Global Positioning System (GPS) system. Each ground user is equipped with a low cost ground terminal that has a synchronization subsystem attached to it. The system design of an onboard Multi-channel Receiver and Demodulator utilizes Quadrature Phase Shift Keying (QPSK) as the modulation technique. This technique provides the best figure of merit, i.e., the lowest transmitter power requirement per communication channel.

  19. Multi-Objective Multi-User Scheduling for Space Science Missions

    NASA Technical Reports Server (NTRS)

    Johnston, Mark D.; Giuliano, Mark

    2010-01-01

    We have developed an architecture called MUSE (Multi-User Scheduling Environment) to enable the integration of multi-objective evolutionary algorithms with existing domain planning and scheduling tools. Our approach is intended to make it possible to re-use existing software, while obtaining the advantages of multi-objective optimization algorithms. This approach enables multiple participants to actively engage in the optimization process, each representing one or more objectives in the optimization problem. As initial applications, we apply our approach to scheduling the James Webb Space Telescope, where three objectives are modeled: minimizing wasted time, minimizing the number of observations that miss their last planning opportunity in a year, and minimizing the (vector) build up of angular momentum that would necessitate the use of mission critical propellant to dump the momentum. As a second application area, we model aspects of the Cassini science planning process, including the trade-off between collecting data (subject to onboard recorder capacity) and transmitting saved data to Earth. A third mission application is that of scheduling the Cluster 4-spacecraft constellation plasma experiment. In this paper we describe our overall architecture and our adaptations for these different application domains. We also describe our plans for applying this approach to other science mission planning and scheduling problems in the future.

  20. NENIMF: Northeast National Ion Microprobe Facility - A Multi-User Facility for SIMS Microanalysis

    NASA Astrophysics Data System (ADS)

    Layne, G. D.; Shimizu, N.

    2002-12-01

    The MIT-Brown-Harvard Regional Ion Microprobe Facility was one of the earliest multi-user facilities enabled by Dan Weill's Instrumentation and Facilities Program - and began with the delivery of a Cameca IMS 3f ion microprobe to MIT in 1978. The Northeast National Ion Microprobe Facility (NENIMF) is the direct descendant of this original facility. Now housed at WHOI, the facility incorporates both the original IMS 3f, and a new generation, high transmission-high resolution instrument - the Cameca IMS 1270. Purchased with support from NSF, and from a consortium of academic institutions in the Northeast (The American Museum of Natural History, Brown University, The Lamont-Doherty Earth Observatory, MIT, Rensselaer Polytechnic Institute, WHOI) - this latest instrument was delivered and installed during 1996. NENIMF continues to be supported by NSF EAR I&F as a multi-user facility for geochemical research. Work at NENIMF has extended the original design strength of the IMS 1270 for microanalytical U-Pb zircon geochronology to a wide variety of novel and improved techniques for geochemical research. Isotope microanalysis for studies in volcanology and petrology is currently the largest single component of facility activity. This includes the direct measurement of Pb isotopes in melt inclusions, an application developed at NENIMF, which is making an increasingly significant contribution to our understanding of basalt petrogenesis. This same technique has also been extended to the determination of Pb isotopes in detrital feldspar grains, for the study of sedimentary provenance and tectonics of the Himalayas and other terrains. The determination of δ11B in volcanic melt inclusions has also proven to be a powerful tool in the modeling of subduction-related magmatism. The recent development of δ34S and δ37Cl determination in glasses is being applied to studies of the behavior of these volatile elements in both natural and experimental systems. Other recent undertakings

  1. Simultaneous injection of stable and radioactive ions into upgraded multi-user atlas

    NASA Astrophysics Data System (ADS)

    Perry, Amichay

    Argonne Tandem Linac Accelerator System (ATLAS) is a Department of Energy (DOE) national user research facility, located at Argonne National Laboratory (ANL). Presently, Radioactive Ion Beams (RIBs) produced in the Californium Rare Isotope Breeder Upgrade (CARIBU) facility are charge bred in an Electron Cyclotron Resonance (ECR) charge breeder prior to post acceleration in ATLAS. A new state of the art Electron Beam Ion Source charge breeder, the CARIBU-EBIS charge breeder, has been developed (not in the scope of the work presented here) at ANL to replace the existing ECR charge breeder for charge breeding RIBs generated in CARIBU. The CARIBU-EBIS charge breeder is now in the final stages of offline at the Accelerator Development Test Facility (ADTF). A significant part of the commissioning effort has been devoted to testing the source by breeding singly-charged cesium ions injected from a surface ionization source. Characterization of the CARIBU-EBIS performance has been accomplished through a comparison between the measured properties of extracted beams and simulation results. Following its offline commissioning, CARIBU-EBIS will be relocated to its permanent location in ATLAS. An electrostatic transport line has been designed to transport RIBs from CARIBU and inject them into CARIBU-EBIS. In addition, modifications to the existing ATLAS Low Energy Beam Transport (LEBT) were required in order to transport the charge bred RIBs from CARIBU-EBIS to ATLAS. A proposal for upgrading ATLAS to a multi-user facility has been explored as well. In this context, beam dynamics simulations show that further modifications to the ATLAS LEBT will enable the simultaneous injection and acceleration of RIBs and stable beams in ATLAS. Furthermore, a novel technique proposed by Ostroumov et al. will allow for the acceleration of multiple charge states from CARIBU-EBIS, thereby increasing the intensity of available RIBs by up to 60%.

  2. Capacitive micromachined ultrasonic transducers using commercial multi-user MUMPs process: capability and limitations.

    PubMed

    Liu, Jessica; Oakley, Clyde; Shandas, Robin

    2009-12-01

    The objective of this work is to construct capacitive micromachined ultrasound transducers (cMUTs) using multi-user microelectromechanical systems (MEMS) processess (MUMPs) and to analyze the capability of this process relative to the customized processes commonly in use. The MUMPs process has the advantages of low cost and accessibility to general users since it is not necessary to have access to customized fabrication capability such as wafer-bonding and sacrificial release processes. While other researchers have reported fabricating cMUTs using the MUMPs process none has reported the limitations in the process that arise due to the use of standard design rules that place limitations on the material thicknesses, gap thicknesses, and materials that may be used. In this paper we explain these limitations, and analyze the capabilities using 1D modeling, Finite Element Analysis, and experimental devices. We show that one of the limitations is that collapse voltage and center frequency can not be controlled independently. However, center frequencies up to 9 MHz can be achieved with collapse voltages of less than 200 V making such devices suitable for medical and non-destructive evaluation imaging applications. Since the membrane and base electrodes are made of polysilicon, there is a larger series resistance than that resulting from processes that use metal electrodes. We show that the series resistance is not a significant problem. The conductive polysilicon can also destroy the cMUT if the top membrane is pulled in the bottom. As a solution we propose the application of an additional dielectric layer. Finally we demonstrate a device built with a novel beam construction that produces transmitted pressure pulse into air with 6% bandwidth and agrees reasonably well with the 1D model. We conclude that cMUTs made with MUMPs process have some limitations that are not present in customized processes. However, these limitations may be overcome with the proper design

  3. Trends in the salience of data collected in a multi user virtual environment: An exploratory study

    NASA Astrophysics Data System (ADS)

    Tutwiler, M. Shane

    In this study, by exploring patterns in the degree of physical salience of the data the students collected, I investigated the relationship between the level of students' tendency to frame explanations in terms of complex patterns and evidence of how they attend to and select data in support of their developing understandings of causal relationships. I accomplished this by analyzing longitudinal data collected as part of a larger study of 143 7th grade students (clustered within 36 teams, 5 teachers, and 2 schools in the same Northeastern school district) as they navigated and collected data in an ecosystems-based multi-user virtual environment curriculum known as the EcoMUVE Pond module (Metcalf, Kamarainen, Tutwiler, Grotzer, Dede, 2011) . Using individual growth modeling (Singer & Willett, 2003) I found no direct link between student pre-intervention tendency to offer explanations containing complex causal components and patterns of physical salience-driven data collection (average physical salience level, number of low physical salience data points collected, and proportion of low physical salience data points collected), though prior science content knowledge did affect the initial status and rate of change of outcomes in the average physical salience level and proportion of low physical salience data collected over time. The findings of this study suggest two issues for consideration about the use of MUVEs to study student data collection behaviors in complex spaces. Firstly, the structure of the curriculum in which the MUVE is embedded might have a direct effect on what types of data students choose to collect. This undercuts our ability to make inferences about student-driven decisions to collect specific types of data, and suggests that a more open-ended curricular model might be better suited to this type of inquiry. Secondly, differences between teachers' choices in how to facilitate the units likely contribute to the variance in student data collection

  4. Immune Tolerance Maintained by Cooperative Interactions between T Cells and Antigen Presenting Cells Shapes a Diverse TCR Repertoire.

    PubMed

    Best, Katharine; Chain, Benny; Watkins, Chris

    2015-01-01

    The T cell population in an individual needs to avoid harmful activation by self peptides while maintaining the ability to respond to an unknown set of foreign peptides. This property is acquired by a combination of thymic and extra-thymic mechanisms. We extend current models for the development of self/non-self discrimination to consider the acquisition of self-tolerance as an emergent system level property of the overall T cell receptor repertoire. We propose that tolerance is established at the level of the antigen presenting cell/T cell cluster, which facilitates and integrates cooperative interactions between T cells of different specificities. The threshold for self-reactivity is therefore imposed at a population level, and not at the level of the individual T cell/antigen encounter. Mathematically, the model can be formulated as a linear programing optimization problem that can be implemented as a multiplicative update algorithm, which shows a rapid convergence to a stable state. The model constrains self-reactivity within a predefined threshold, but maintains repertoire diversity and cross reactivity which are key characteristics of human T cell immunity. We show further that the size of individual clones in the model repertoire becomes heterogeneous, and that new clones can establish themselves even when the repertoire has stabilized. Our study combines the salient features of the "danger" model of self/non-self discrimination with the concepts of quorum sensing, and extends repertoire generation models to encompass the establishment of tolerance. Furthermore, the dynamic and continuous repertoire reshaping, which underlies tolerance in this model, suggests opportunities for therapeutic intervention to achieve long-term tolerance following transplantation. PMID:26300880

  5. Performance of a novel LED lamp arrangement to reduce SNR fluctuation for multi-user visible light communication systems.

    PubMed

    Wang, Zixiong; Yu, Changyuan; Zhong, Wen-De; Chen, Jian; Chen, Wei

    2012-02-13

    This paper investigates the performance of our recently proposed LED lamp arrangement to reduce the SNR fluctuation from different locations in the room for multi-user visible light communications. The LED lamp arrangement consists of 4 LED lamps positioned in the corners and 12 LED lamps spread evenly on a circle. Our studies show that the SNR fluctuation under such a LED lamp arrangement is reduced from 14.5 dB to 0.9 dB, which guarantees that users can obtain almost identical communication quality, regardless of their locations. After time domain zero-forcing (ZF) equalization, the BER performances and channel capacities of 100-Mbit/s and 200-Mbit/s bipolar on-off-keying (OOK) signal with most significant inter-symbol interference (ISI) are very close to that of the channel without any ISI caused by this LED lamp arrangement.

  6. Heavy-tailed distribution of the SSH Brute-force attack duration in a multi-user environment

    NASA Astrophysics Data System (ADS)

    Lee, Jae-Kook; Kim, Sung-Jun; Park, Chan Yeol; Hong, Taeyoung; Chae, Huiseung

    2016-07-01

    Quite a number of cyber-attacks to be place against supercomputers that provide highperformance computing (HPC) services to public researcher. Particularly, although the secure shell protocol (SSH) brute-force attack is one of the traditional attack methods, it is still being used. Because stealth attacks that feign regular access may occur, they are even harder to detect. In this paper, we introduce methods to detect SSH brute-force attacks by analyzing the server's unsuccessful access logs and the firewall's drop events in a multi-user environment. Then, we analyze the durations of the SSH brute-force attacks that are detected by applying these methods. The results of an analysis of about 10 thousands attack source IP addresses show that the behaviors of abnormal users using SSH brute-force attacks are based on human dynamic characteristics of a typical heavy-tailed distribution.

  7. Andragogical Characteristics and Expectations of University of Hawai'i Adult Learners in a 3D Multi-User Virtual Environment

    ERIC Educational Resources Information Center

    Meeder, Rebecca L.

    2012-01-01

    The purpose of this study was to discover which andragogical characteristics and expectations of adult learners manifested themselves in the three-dimensional, multi-user virtual environment known as Second Life. This digital ethnographic study focused specifically on adult students within the University of Hawai'i Second Life group and their…

  8. School Exchanges: Cultural Diversity, Conflict and Cooperation. Report of the Conference (7th, Dubrovnik, Croatia, September 11-15, 1996).

    ERIC Educational Resources Information Center

    Council for Cultural Cooperation, Strasbourg (France).

    The Council of Europe was founded in 1949 to achieve greater unity among European parliamentary democracies. The Council for Cultural Co-operation (CDCC) is responsible for the Council of Education's work on education, culture, and sport. This publication contains proceedings of the CDCC Conference of the Network on School Links and Exchangers.…

  9. Performance of Multi-User Transmitter Pre-Processing Assisted Multi-Cell IDMA System for Downlink Transmission

    NASA Astrophysics Data System (ADS)

    Partibane, B.; Nagarajan, V.; Vishvaksenan, K. S.; Kalidoss, R.

    2015-06-01

    In this paper, we present the performance of multi-user transmitter pre-processing (MUTP) assisted coded-interleave division multiple access (IDMA) system over correlated frequency-selective channels for downlink communication. We realize MUTP using singular value decomposition (SVD) technique, which exploits the channel state information (CSI) of all the active users that is acquired via feedback channels. We consider the MUTP technique to alleviate the effects of co-channel interference (CCI) and multiple access interference (MAI). To be specific, we estimate the CSI using least square error (LSE) algorithm at each of the mobile stations (MSs) and perform vector quantization using Lloyd's algorithm, and feedback the bits that represents the quantized magnitudes and phases to the base station (BS) through the dedicated low rate noisy channel. Finally we recover the quantized bits at the BS to formulate the pre-processing matrix. The performance of MUTP aided IDMA systems are evaluated for five types of delay spread distributions pertaining to long-term evolution (LTE) and Stanford University Interim (SUI) channel models. We also compare the performance of MUTP with minimum mean square error (MMSE) detector for the coded IDMA system. The considered TP scheme alleviates the effects of CCI with less complex signal detection at the MSs when compared to MMSE detector. Further, our simulation results reveal that SVD-based MUTP assisted coded IDMA system outperforms the MMSE detector in terms of achievable bit error rate (BER) with low signal-to-noise ratio (SNR) requirement by mitigating the effects of CCI and MAI.

  10. Bidirectional and Multi-User Telerehabilitation System: Clinical Effect on Balance, Functional Activity, and Satisfaction in Patients with Chronic Stroke Living in Long-Term Care Facilities

    PubMed Central

    Lin, Kwan-Hwa; Chen, Chin-Hsing; Chen, You-Yin; Huang, Wen-Tzeng; Lai, Jin-Shin; Yu, Shang-Ming; Chang, Yuan-Jen

    2014-01-01

    Background The application of internet technology for telerehabilitation in patients with stroke has developed rapidly. Objective The current study aimed to evaluate the effect of a bidirectional and multi-user telerehabilitation system on balance and satisfaction in patients with chronic stroke living in long-term care facilities (LTCFs). Method This pilot study used a multi-site, blocked randomization design. Twenty-four participants from three LTCFs were recruited, and the participants were randomly assigned into the telerehabilitation (Tele) and conventional therapy (Conv) groups within each LTCF. Tele group received telerehabilitation but the Conv group received conventional therapy with two persons in each group for three sessions per week and for four weeks. The outcome measures included Berg Balance Scale (BBS), Barthel Index (BI), and the telerehabilitation satisfaction of the participants. Setting A telerehabilitation system included “therapist end” in a laboratory, and the “client end” in LTCFs. The conventional therapy was conducted in LTCFs. Results Training programs conducted for both the Tele and Conv groups showed significant effects within groups on the participant BBS as well as the total and self-care scores of BI. No significant difference between groups could be demonstrated. The satisfaction of participants between the Tele and the Conv groups also did not show significant difference. Conclusions This pilot study indicated that the multi-user telerehabilitation program is feasible for improving the balance and functional activity similar to conventional therapy in patients with chronic stroke living in LTCFs. PMID:25019632

  11. Diversity of Aerosol Optical Thickness in analysis and forecasting modes of the models from the International Cooperative for Aerosol Prediction Multi-Model Ensemble (ICAP-MME)

    NASA Astrophysics Data System (ADS)

    Lynch, P.

    2014-12-01

    With the emergence of global aerosol models intended for operational forecasting use at global numerical weather prediction (NWP) centers, the International Cooperative for Aerosol Prediction (ICAP) was founded in 2010. One of the objectives of ICAP is to develop a global multi-model aerosol forecasting ensemble (ICAP-MME) for operational and basic research use. To increase the accuracy of aerosol forecasts, several of the NWP centers have incorporated assimilation of satellite and/or ground-based observations of aerosol optical thickness (AOT), the most widely available and evaluated aerosol parameter. The ICAP models are independent in their underlying meteorology, as well as aerosol sources, sinks, microphysics and chemistry. The diversity of aerosol representations in the aerosol forecast models results in differences in AOT. In addition, for models that include AOT assimilations, the diversity in assimilation methodology, the observed AOT data to be assimilated, and the pre-assimilation treatments of input data also leads to differences in the AOT analyses. Drawing from members of the ICAP latest generation of quasi-operational aerosol models, five day AOT forecasts and AOT analyses are analyzed from four multi-species models which have AOT assimilations: ECMWF, JMA, NASA GSFC/GMAO, and NRL/FNMOC. For forecast mode only, we also include the dust products from NOAA NGAC, BSC, and UK Met office in our analysis leading to a total of 7 dust models. AOT at 550nm from all models are validated at regionally representative Aerosol Robotic Network (AERONET) sites and a data assimilation grade multi-satellite aerosol analysis. These analyses are also compared with the recently developed AOT reanalysis at NRL. Here we will present the basic verification characteristics of the ICAP-MME, and identify regions of diversity between model analyses and forecasts. Notably, as in many other ensemble environments, the multi model ensemble consensus mean outperforms all of the

  12. The Effect of the Use of the 3-D Multi-User Virtual Environment "Second Life" on Student Motivation and Language Proficiency in Courses of Spanish as a Foreign Language

    ERIC Educational Resources Information Center

    Pares-Toral, Maria T.

    2013-01-01

    The ever increasing popularity of virtual worlds, also known as 3-D multi-user virtual environments (MUVEs) or simply virtual worlds provides language instructors with a new tool they can exploit in their courses. For now, "Second Life" is one of the most popular MUVEs used for teaching and learning, and although "Second Life"…

  13. Synthetic Yeast Cooperation

    NASA Astrophysics Data System (ADS)

    Shou, Wenying; Burton, Justin

    2010-03-01

    Cooperation is wide-spread and has been postulated to drive major transitions in evolution. However, Darwinian selection favors ``cheaters'' that consume benefits without paying a fair cost. How did cooperation evolve against the threat of cheaters? To investigate the evolutionary trajectories of cooperation, we created a genetically tractable system that can be observed as it evolves from inception. The system consists of two engineered yeast strains -- a red-fluorescent strain that requires adenine and releases lysine and a yellow-fluorescent strain that requires lysine and releases adenine. Cells that consume but not supply metabolites would be cheaters. From the properties of two cooperating strains, we calculated and experimentally verified the minimal initial cell densities required for the viability of the cooperative system in the absence of exogenously added adenine and lysine. Strikingly, evolved cooperative systems were viable at 100-fold lower initial cell densities than their ancestors. We are investigating the nature and diversity of pro-cooperation changes, the dynamics of cooperator-cheater cocultures, and the effects of spatial environment on cooperation and cheating.

  14. Cooperative Poetry.

    ERIC Educational Resources Information Center

    McEwen, Pam

    1989-01-01

    Describes "cooperative poetry," a group poetry-writing exercise combining brainstorming, rehearsing, choral reading, assisted reading, memorization, sequencing, and vocabulary development, as well as providing an opportunity for group cooperation. (MM)

  15. Multi-user investigation organizer

    NASA Technical Reports Server (NTRS)

    Keller, Richard M. (Inventor); Panontin, Tina L. (Inventor); Carvalho, Robert E. (Inventor); Sturken, Ian (Inventor); Williams, James F. (Inventor); Wolfe, Shawn R. (Inventor); Gawdiak, Yuri O. (Inventor)

    2009-01-01

    A system that allows a team of geographically dispersed users to collaboratively analyze a mishap event. The system includes a reconfigurable ontology, including instances that are related to and characterize the mishap, a semantic network that receives, indexes and stores, for retrieval, viewing and editing, the instances and links between the instances, a network browser interface for retrieving and viewing screens that present the instances and links to other instances and that allow editing thereof, and a rule-based inference engine, including a collection of rules associated with establishment of links between the instances. A possible conclusion arising from analysis of the mishap event may be characterized as one or more of: not a credible conclusion; an unlikely conclusion; a credible conclusion; conclusion needs analysis; conclusion needs supporting data; conclusion proposed to be closed; and an un-reviewed conclusion.

  16. The Multi-User Droplet Combustion Apparatus: the Development and Integration Concept for Droplet Combustion Payloads in the Fluids and Combustion Facility Combustion Integrated Rack

    NASA Astrophysics Data System (ADS)

    Myhre, C. A.

    2002-01-01

    The Multi-user Droplet Combustion Apparatus (MDCA) is a multi-user facility designed to accommodate four different droplet combustion science experiments. The MDCA will conduct experiments using the Combustion Integrated Rack (CIR) of the NASA Glenn Research Center's Fluids and Combustion Facility (FCF). The payload is planned for the International Space Station. The MDCA, in conjunction with the CIR, will allow for cost effective extended access to the microgravity environment, not possible on previous space flights. It is currently in the Engineering Model build phase with a planned flight launch with CIR in 2004. This paper provides an overview of the capabilities and development status of the MDCA. The MDCA contains the hardware and software required to conduct unique droplet combustion experiments in space. It consists of a Chamber Insert Assembly, an Avionics Package, and a multiple array of diagnostics. Its modular approach permits on-orbit changes for accommodating different fuels, fuel flow rates, soot sampling mechanisms, and varying droplet support and translation mechanisms to accommodate multiple investigations. Unique diagnostic measurement capabilities for each investigation are also provided. Additional hardware provided by the CIR facility includes the structural support, a combustion chamber, utilities for the avionics and diagnostic packages, and the fuel mixing capability for PI specific combustion chamber environments. Common diagnostics provided by the CIR will also be utilized by the MDCA. Single combustible fuel droplets of varying sizes, freely deployed or supported by a tether are planned for study using the MDCA. Such research supports how liquid-fuel-droplets ignite, spread, and extinguish under quiescent microgravity conditions. This understanding will help us develop more efficient energy production and propulsion systems on Earth and in space, deal better with combustion generated pollution, and address fire hazards associated with

  17. Cooperative Education.

    ERIC Educational Resources Information Center

    Office of Education (DHEW), Washington, DC.

    Cooperative education programs, a nontraditional blending of practice and theory, have become an important feature of current higher education. Some educators estimate that by 1984 half of the higher education institutions in the United States will have developed some form of cooperative education. The Federal government's recent involvement in…

  18. Hormonal mechanisms of cooperative behaviour

    PubMed Central

    Soares, Marta C.; Bshary, Redouan; Fusani, Leonida; Goymann, Wolfgang; Hau, Michaela; Hirschenhauser, Katharina; Oliveira, Rui F.

    2010-01-01

    Research on the diversity, evolution and stability of cooperative behaviour has generated a considerable body of work. As concepts simplify the real world, theoretical solutions are typically also simple. Real behaviour, in contrast, is often much more diverse. Such diversity, which is increasingly acknowledged to help in stabilizing cooperative outcomes, warrants detailed research about the proximate mechanisms underlying decision-making. Our aim here is to focus on the potential role of neuroendocrine mechanisms on the regulation of the expression of cooperative behaviour in vertebrates. We first provide a brief introduction into the neuroendocrine basis of social behaviour. We then evaluate how hormones may influence known cognitive modules that are involved in decision-making processes that may lead to cooperative behaviour. Based on this evaluation, we will discuss specific examples of how hormones may contribute to the variability of cooperative behaviour at three different levels: (i) within an individual; (ii) between individuals and (iii) between species. We hope that these ideas spur increased research on the behavioural endocrinology of cooperation. PMID:20679116

  19. Religious Diversity in the Schools.

    ERIC Educational Resources Information Center

    Michel, George J.; Smith, William Gause; Vickers, Dianne Koenig; Brown, Elsie

    This document contains four papers that address constitutional issues of religious diversity in the schools. The first paper, "Religious Diversity in the Schools--The Overview" (George J. Michel), provides an overview of religious diversity in American public schools, with a focus on the long history of cooperation with Christian churches. It…

  20. Predicting Human Cooperation.

    PubMed

    Nay, John J; Vorobeychik, Yevgeniy

    2016-01-01

    The Prisoner's Dilemma has been a subject of extensive research due to its importance in understanding the ever-present tension between individual self-interest and social benefit. A strictly dominant strategy in a Prisoner's Dilemma (defection), when played by both players, is mutually harmful. Repetition of the Prisoner's Dilemma can give rise to cooperation as an equilibrium, but defection is as well, and this ambiguity is difficult to resolve. The numerous behavioral experiments investigating the Prisoner's Dilemma highlight that players often cooperate, but the level of cooperation varies significantly with the specifics of the experimental predicament. We present the first computational model of human behavior in repeated Prisoner's Dilemma games that unifies the diversity of experimental observations in a systematic and quantitatively reliable manner. Our model relies on data we integrated from many experiments, comprising 168,386 individual decisions. The model is composed of two pieces: the first predicts the first-period action using solely the structural game parameters, while the second predicts dynamic actions using both game parameters and history of play. Our model is successful not merely at fitting the data, but in predicting behavior at multiple scales in experimental designs not used for calibration, using only information about the game structure. We demonstrate the power of our approach through a simulation analysis revealing how to best promote human cooperation. PMID:27171417

  1. Predicting Human Cooperation

    PubMed Central

    Nay, John J.; Vorobeychik, Yevgeniy

    2016-01-01

    The Prisoner’s Dilemma has been a subject of extensive research due to its importance in understanding the ever-present tension between individual self-interest and social benefit. A strictly dominant strategy in a Prisoner’s Dilemma (defection), when played by both players, is mutually harmful. Repetition of the Prisoner’s Dilemma can give rise to cooperation as an equilibrium, but defection is as well, and this ambiguity is difficult to resolve. The numerous behavioral experiments investigating the Prisoner’s Dilemma highlight that players often cooperate, but the level of cooperation varies significantly with the specifics of the experimental predicament. We present the first computational model of human behavior in repeated Prisoner’s Dilemma games that unifies the diversity of experimental observations in a systematic and quantitatively reliable manner. Our model relies on data we integrated from many experiments, comprising 168,386 individual decisions. The model is composed of two pieces: the first predicts the first-period action using solely the structural game parameters, while the second predicts dynamic actions using both game parameters and history of play. Our model is successful not merely at fitting the data, but in predicting behavior at multiple scales in experimental designs not used for calibration, using only information about the game structure. We demonstrate the power of our approach through a simulation analysis revealing how to best promote human cooperation. PMID:27171417

  2. Teacher Cooperatives

    ERIC Educational Resources Information Center

    Hawkins, Beth

    2009-01-01

    Twenty years ago, when the late Albert Shanker endorsed the notion of innovative schools operating outside conventional district bureaucracies, his aim was to put teachers at the helm. Today there are nearly 80 teacher-governed charter schools around the country. Although most are legally constituted as worker cooperatives, they better resemble…

  3. Cooperative Education.

    ERIC Educational Resources Information Center

    Brown, Robert L.

    Cooperative education involves on-campus instruction and off-campus work experience. These programs can be referred to as work study, field work, or work experience. The student has the advantage of applying his knowledge in a work situation; the college gains financial benefits; and the employer has the opportunity to influence the student to…

  4. Cooperative Learning.

    ERIC Educational Resources Information Center

    Slavin, Robert E.

    1980-01-01

    Small-group cooperative learning methods have improved achievement, low and high level cognitive learning, race relations and mutual student concern. Most of the research focuses on four approaches: Teams Games Tournament (DeVries), Student Teams Achievement Divisions (Slavin), Jigsaw (Aronson) and Small Group Teaching (Sharan). (Author/CP)

  5. The Worker's Cooperative = Cooperativas de Trabajadores Duenos.

    ERIC Educational Resources Information Center

    Hernandez, Mayra Lee

    Written in Spanish and English (on facing pages), this manual is a practical guide for those interested in forming a worker-owned cooperative. It includes examples based on the personal experience of teaching about cooperativism and worker-owned cooperatives to a group of construction workers with diverse levels of education; vocabulary and…

  6. Cooperative pulses

    NASA Astrophysics Data System (ADS)

    Braun, Michael; Glaser, Steffen J.

    2010-11-01

    We introduce the concept of cooperative (COOP) pulses which are designed to compensate each other's imperfections. In multi-scan experiments, COOP pulses can cancel undesired signal contributions, complementing and generalizing phase cycles. COOP pulses can be efficiently optimized using an extended version of the optimal-control-based gradient ascent pulse engineering (GRAPE) algorithm. The advantage of the COOP approach is experimentally demonstrated for broadband and band-selective pulses.

  7. International cooperation.

    PubMed

    1999-04-01

    As the most densely populated country in the world, China actively conducts international exchanges and cooperation. It takes every opportunity to publicize its family planning policies and practices during international forums. Moreover, the country's State Family Planning Commission has been collaborating with the United Nations Population Fund in implementing health and family planning programs. This program covers public awareness campaigns, technical services, sex education for the youth, and social marketing. For years, China has also been cooperating with WHO in the area of family planning and reproductive health, and has established partnership with the Japanese Organization for International Cooperation in Family Planning. In addition, the State Family Planning Commission has worked with the Public Media Center of the US as well as with the Rockefeller Foundation and Ford Foundation in introducing "contraceptive methods by informed choice" and "male participation in family planning" in the rural areas of the country. China has also worked closely with many other developing countries on population issues. In October 1998, China collaborated with the Partners in Population and Development for a reporting mission that was attended by journalists from 11 countries.

  8. The FUS3 MAPK signaling pathway of the citrus pathogen Alternaria alternata functions independently or cooperatively with the fungal redox-responsive AP1 regulator for diverse developmental, physiological and pathogenic processes.

    PubMed

    Lin, Ching-Hsuan; Yang, Siwy Ling; Wang, Nan-Yi; Chung, Kuang-Ren

    2010-04-01

    Alternaria alternata, the fungus that causes citrus brown spot, invades its hosts primarily through the production and action of a host-selective ACT toxin that kills citrus cells prior to invasion. In this study, we show that, in the tangerine pathotype of A. alternata, a mitogen-activated protein kinase (MAPK)-mediated signaling pathway governs a number of biological functions, either separately or in a cooperative manner, with the AaAP1 gene encoding a transcription regulator. The reported MAPK is encoded by the AaFUS3 gene, which we show to be necessary for conidial development, resistance to copper fungicides, melanin biosynthesis, and particularly, for elaboration of the penetration process. In contrast, AaFUS3 negatively controls salt tolerance and production of several hydrolytic enzymes. AaFUS3 has no apparent role in the biosynthesis of host-selective toxin or in resistance to oxidative stress. Both AaAP1 and AaFUS3 are required for fungal resistance to 2,3,5-triiodobenzoic acid (TIBA), 2-chloro-5-hydroxypyridine (CHP), diethyl maleate (DEM), and many pyridine-containing compounds. A strain with mutations in both AaAP1 and AaFUS3 displayed an increased sensitivity to these compounds. Expression of the AaAP1 and AaFUS3 genes and phosphorylation of AaFUS3 were also induced by CHP, DEM, or TIBA. Expression of two genes coding for a putative MFS transporter was coordinately regulated by AaAP1 and AaFUS3. The AaAP1::sGFP (synthetic green fluorescent protein) fusion protein became localized in the nucleus in response to CHP or TIBA. Inactivation of the AaAP1 gene, however, promoted phosphorylation of AaFUS3. Taken together, our results indicate that A. alternata utilizes specialized or synergistic regulatory interactions between the AP1 and MAPK signaling pathways for diverse physiological functions.

  9. Cooperation: the foundation of improvement.

    PubMed

    Clemmer, T P; Spuhler, V J; Berwick, D M; Nolan, T W

    1998-06-15

    Cooperation--working together to produce mutual benefit or attain a common purpose--is almost inseparable from the quest for improvement. Although the case for cooperation can be made on ethical grounds, neither the motivation for nor the effects of cooperation need to be interpreted solely in terms of altruism. Cooperation can be a shrewd and pragmatic strategy for accomplishing personal goals in an interdependent system. Earlier papers in this series have explored the conceptual roots of modern approaches to improvement, which lie in systems theory. To improve systems, we must usually attend first and foremost to interactions. Among humans, "better interaction" is almost synonymous with "better cooperation." Physicians have ample opportunities and, indeed, an obligation to cooperate with other physicians in the same or different specialties, with nurses and other clinical workers, with administrators, and with patients and families. Many intellectual disciplines have made cooperation an object of study. These include anthropology; social psychology; genetics; biology; mathematics; game theory; linguistics; operations research; economics; and, of course, moral and rational philosophy. Scientifically grounded methods to enhance cooperation include developing a shared purpose; creating an open, safe environment; including all who share a common purpose and encouraging diverse viewpoints; negotiating agreement; and insisting on fairness and equity in the application of rules. These methods apply at the organizational level and at the level of the individual physician. This paper describes the application of these methods at the organizational level and focuses on one especially successful example of system-level cooperation in a care delivery site where interactions matter a great deal: the modern intensive care unit. PMID:9625663

  10. Infusing Cooperative Learning into an EFL Classroom

    ERIC Educational Resources Information Center

    Tuan, Luu Trong

    2010-01-01

    This study sought to investigate student diversities in terms of learning styles and linguistic competence, and the extent to which students change as regards participation, interaction and achievement through Cooperative Learning activities embracing their diversities. 77 first-year EFL students from from the two reading classes, one treated as…

  11. Diverse Thinking about Diversity

    ERIC Educational Resources Information Center

    Kaplan, Sandra N.

    2013-01-01

    This article focuses on the concept of diversity in educational decision making. It is noted that the differences that distinguish the needs, interests and abilities are identified by educators. It lists misconceptions resulting from not attending to within-group diversity, and states that a "loss of self" for individual members of…

  12. Plant cooperation

    PubMed Central

    Dudley, Susan A.

    2015-01-01

    The study of plant behaviour will be aided by conceptual approaches and terminology for cooperation, altruism and helping. The plant literature has a rich discussion of helping between species while the animal literature has an extensive and somewhat contentious discussion of within-species helping. Here, I identify and synthesize concepts, terminology and some practical methodology for speaking about helping in plant populations and measuring the costs and benefits. I use Lehmann and Keller's (2006) classification scheme for animal helping and McIntire and Fajardo's (2014) synthesis of facilitation to provide starting points for classifying the mechanisms of how and why organisms help each other. Contextual theory is discussed as a mechanism for understanding and measuring the fitness consequences of helping. I synthesize helping into four categories. The act of helping can be costly to the helper. If the helper gains indirect fitness by helping relatives but loses direct fitness, this is altruism, and it only occurs within species. Helpers can exchange costly help, which is called mutualism when between species, and reciprocation when within a species. The act of helping can directly benefit the helper as well as the recipient, either as an epiphenomenon resulting from behaviours under natural selection for other reasons, or because the helper is creating a mutual benefit, such as satiating predators or supporting a mutualism. Facilitation between species by stress amelioration, creation of novel ecosystems and habitat complexity often meets the definition of epiphenomenon helping. Within species, this kind of helping is called by-product mutualism. If the helping is under selection to create a mutual benefit shared by others, between species this is facilitation with service sharing or access to resources and within species, direct benefits by mutual benefits. These classifications provide a clear starting point for addressing the subject of helping behaviours

  13. Plant cooperation.

    PubMed

    Dudley, Susan A

    2015-01-01

    The study of plant behaviour will be aided by conceptual approaches and terminology for cooperation, altruism and helping. The plant literature has a rich discussion of helping between species while the animal literature has an extensive and somewhat contentious discussion of within-species helping. Here, I identify and synthesize concepts, terminology and some practical methodology for speaking about helping in plant populations and measuring the costs and benefits. I use Lehmann and Keller's (2006) classification scheme for animal helping and McIntire and Fajardo's (2014) synthesis of facilitation to provide starting points for classifying the mechanisms of how and why organisms help each other. Contextual theory is discussed as a mechanism for understanding and measuring the fitness consequences of helping. I synthesize helping into four categories. The act of helping can be costly to the helper. If the helper gains indirect fitness by helping relatives but loses direct fitness, this is altruism, and it only occurs within species. Helpers can exchange costly help, which is called mutualism when between species, and reciprocation when within a species. The act of helping can directly benefit the helper as well as the recipient, either as an epiphenomenon resulting from behaviours under natural selection for other reasons, or because the helper is creating a mutual benefit, such as satiating predators or supporting a mutualism. Facilitation between species by stress amelioration, creation of novel ecosystems and habitat complexity often meets the definition of epiphenomenon helping. Within species, this kind of helping is called by-product mutualism. If the helping is under selection to create a mutual benefit shared by others, between species this is facilitation with service sharing or access to resources and within species, direct benefits by mutual benefits. These classifications provide a clear starting point for addressing the subject of helping behaviours

  14. PREFACE: Cooperative dynamics Cooperative dynamics

    NASA Astrophysics Data System (ADS)

    Gov, Nir

    2011-09-01

    The dynamics within living cells are dominated by non-equilibrium processes that consume chemical energy (usually in the form of ATP, adenosine triphosphate) and convert it into mechanical forces and motion. The mechanisms that allow this conversion process are mostly driven by the components of the cytoskeleton: (i) directed (polar) polymerization of filaments (either actin or microtubules) and (ii) molecular motors. The forces and motions produced by these two components of the cytoskeleton give rise to the formation of cellular shapes, and drive the intracellular transport and organization. It is clear that these systems present a multi-scale challenge, from the physics of the molecular processes to the organization of many interacting units. Understanding the physical nature of these systems will have a large impact on many fundamental problems in biology and break new grounds in the field of non-equilibrium physics. This field of research has seen a rapid development over the last ten years. Activities in this area range from theoretical and experimental work on the underlying fundamental (bio)physics at the single-molecule level, to investigations (in vivo and in vitro) of the dynamics and patterns of macroscopic pieces of 'living matter'. In this special issue we have gathered contributions that span the whole spectrum of length- and complexity-scales in this field. Some of the works demonstrate how active forces self-organize within the polymerizing cytoskeleton, on the level of cooperative cargo transport via motors or due to active fluxes at the cell membrane. On a larger scale, it is shown that polar filaments coupled to molecular motors give rise to a huge variety of surprising dynamics and patterns: spontaneously looping rings of gliding microtubules, and emergent phases of self-organized filaments and motors in different geometries. All of these articles share the common feature of being out-of-equilibrium, driven by metabolism. As demonstrated here

  15. High resolution time of arrival estimation for a cooperative sensor system

    NASA Astrophysics Data System (ADS)

    Morhart, C.; Biebl, E. M.

    2010-09-01

    Distance resolution of cooperative sensors is limited by the signal bandwidth. For the transmission mainly lower frequency bands are used which are more narrowband than classical radar frequencies. To compensate this resolution problem the combination of a pseudo-noise coded pulse compression system with superresolution time of arrival estimation is proposed. Coded pulsecompression allows secure and fast distance measurement in multi-user scenarios which can easily be adapted for data transmission purposes (Morhart and Biebl, 2009). Due to the lack of available signal bandwidth the measurement accuracy degrades especially in multipath scenarios. Superresolution time of arrival algorithms can improve this behaviour by estimating the channel impulse response out of a band-limited channel view. For the given test system the implementation of a MUSIC algorithm permitted a two times better distance resolution as the standard pulse compression.

  16. Complex Instruction: Equity in Cooperative Learning Classrooms.

    ERIC Educational Resources Information Center

    Cohen, Elizabeth G.; Lotan, Rachel A.; Scarloss, Beth A.; Arellano, Adele R.

    1999-01-01

    Discusses two dimensions of equity within small-group learning--access and equitable relations--describing complex instruction (CI) as an approach that lets educators address these issues. CI teachers use cooperative learning to teach at high academic levels in diverse classrooms. The paper describes CI in action, achievement results in CI…

  17. Implementing Cooperative Learning Methods.

    ERIC Educational Resources Information Center

    Lyons, Paul R.

    This paper identifies the bases and rationale for the concept of cooperative learning; describes the dynamics of the cooperative learning approach; and proposes methods that college faculty can use to enhance student motivation and learning. Cooperative learning is defined and is reported to have positive effects on student achievement, human…

  18. Advising People about Cooperatives.

    ERIC Educational Resources Information Center

    Kirkman, C. H., Jr.; Mohn, Paul O.

    This document provides background and references for educational programs on cooperatives. Seven major topics are covered: Cooperatives Are Distinctive Business Corporations, Types of Cooperatives (such as agricultural, credit, housing, crafts, health, memorial association, fishing, forestry, recreation, labor, buying clubs, consumer, student, and…

  19. Learning to Learn Cooperatively

    ERIC Educational Resources Information Center

    Byrd, Anne Hammond

    2009-01-01

    Cooperative learning, put quite simply, is a type of instruction whereby students work together in small groups to achieve a common goal. Cooperative learning has become increasingly popular as a feature of Communicative Language Teaching (CLT) with benefits that include increased student interest due to the quick pace of cooperative tasks,…

  20. Cooperative Agreements Study Report.

    ERIC Educational Resources Information Center

    Lawton, R. E.; Magruder, D.

    During the 1983 meeting of the Florida Legislature, action was taken to begin a systematic study of the level of cooperation between the Florida public schools K-12 program and the community and junior colleges. The goals and objectives of the Cooperative Agreements Study were to review and compile a list of the cooperative agreements and identify…

  1. Exploring cooperation and competition using agent-based modeling

    PubMed Central

    Elliott, Euel; Kiel, L. Douglas

    2002-01-01

    Agent-based modeling enhances our capacity to model competitive and cooperative behaviors at both the individual and group levels of analysis. Models presented in these proceedings produce consistent results regarding the relative fragility of cooperative regimes among agents operating under diverse rules. These studies also show how competition and cooperation may generate change at both the group and societal level. Agent-based simulation of competitive and cooperative behaviors may reveal the greatest payoff to social science research of all agent-based modeling efforts because of the need to better understand the dynamics of these behaviors in an increasingly interconnected world. PMID:12011396

  2. The Civic Relevance of Interfaith Cooperation for Colleges and Universities

    ERIC Educational Resources Information Center

    Patel, Eboo; Meyer, Cassie

    2011-01-01

    As tensions around religious diversity escalate in America, there is an increased realization that interfaith cooperation has broad civic relevance. In this realization, there is an opportunity for American colleges and universities to play a leadership role in constructively engaging religious diversity. The authors of this article explore the…

  3. Making Cultural Diversity Work in Suburban Georgia.

    ERIC Educational Resources Information Center

    Mahon, J. Patrick

    1997-01-01

    Captures the cooperative spirit of a suburban Georgia high school with 2,000 highly mobile students from 60 countries and speaking over 30 different languages. Staff work to counter stereotypical assumptions and use diversity as a positive resource for learning and promotion of individual excellence. Diversity-management strategies related to…

  4. Rethinking Diversity.

    ERIC Educational Resources Information Center

    Gordon, Jack

    1992-01-01

    Managing diversity is about coping with unassimilated differences, about building systems and a culture that unite different people in a common pursuit without undermining their diversity. The goal of diversity training is a high performance organization rather than a climate in which no one's feathers are ruffled. (SK)

  5. Introduction to "Interfaith Cooperation on Campus": Interfaith Cooperation as an Institution-Wide Priority

    ERIC Educational Resources Information Center

    Patel, Eboo; Meyer, Cassie

    2011-01-01

    As an introduction to a new column focusing on interfaith cooperation on campus, the authors suggest a framework for engaging religious diversity on campus based on institution-wide vision and collaboration across levels of the campus "ecology" that lead to measurable student and campus outcomes. This framework takes into consideration how other…

  6. Cooperation Among Theorem Provers

    NASA Technical Reports Server (NTRS)

    Waldinger, Richard J.

    1998-01-01

    This is a final report, which supports NASA's PECSEE (Persistent Cognizant Software Engineering Environment) effort and complements the Kestrel Institute project "Inference System Integration via Logic Morphism". The ultimate purpose of the project is to develop a superior logical inference mechanism by combining the diverse abilities of multiple cooperating theorem provers. In many years of research, a number of powerful theorem-proving systems have arisen with differing capabilities and strengths. Resolution theorem provers (such as Kestrel's KITP or SRI's, SNARK) deal with first-order logic with equality but not the principle of mathematical induction. The Boyer-Moore theorem prover excels at proof by induction but cannot deal with full first-order logic. Both are highly automated but cannot accept user guidance easily. The PVS system (from SRI) in only automatic within decidable theories, but it has well-designed interactive capabilities: furthermore, it includes higher-order logic, not just first-order logic. The NuPRL system from Cornell University and the STeP system from Stanford University have facilities for constructive logic and temporal logic, respectively - both are interactive. It is often suggested - for example, in the anonymous "QED Manifesto"-that we should pool the resources of all these theorem provers into a single system, so that the strengths of one can compensate for the weaknesses of others, and so that effort will not be duplicated. However, there is no straightforward way of doing this, because each system relies on its own language and logic for its success. Thus. SNARK uses ordinary first-order logic with equality, PVS uses higher-order logic. and NuPRL uses constructive logic. The purpose of this project, and the companion project at Kestrel, has been to use the category-theoretic notion of logic morphism to combine systems with different logics and languages. Kestrel's SPECWARE system has been the vehicle for the implementation.

  7. Regional Renewable Energy Cooperatives

    NASA Astrophysics Data System (ADS)

    Hazendonk, P.; Brown, M. B.; Byrne, J. M.; Harrison, T.; Mueller, R.; Peacock, K.; Usher, J.; Yalamova, R.; Kroebel, R.; Larsen, J.; McNaughton, R.

    2014-12-01

    We are building a multidisciplinary research program linking researchers in agriculture, business, earth science, engineering, humanities and social science. Our goal is to match renewable energy supply and reformed energy demands. The program will be focused on (i) understanding and modifying energy demand, (ii) design and implementation of diverse renewable energy networks. Geomatics technology will be used to map existing energy and waste flows on a neighbourhood, municipal, and regional level. Optimal sites and combinations of sites for solar and wind electrical generation (ridges, rooftops, valley walls) will be identified. Geomatics based site and grid analyses will identify best locations for energy production based on efficient production and connectivity to regional grids and transportation. Design of networks for utilization of waste streams of heat, water, animal and human waste for energy production will be investigated. Agriculture, cities and industry produce many waste streams that are not well utilized. Therefore, establishing a renewable energy resource mapping and planning program for electrical generation, waste heat and energy recovery, biomass collection, and biochar, biodiesel and syngas production is critical to regional energy optimization. Electrical storage and demand management are two priorities that will be investigated. Regional scale cooperatives may use electric vehicle batteries and innovations such as pump storage and concentrated solar molten salt heat storage for steam turbine electrical generation. Energy demand management is poorly explored in Canada and elsewhere - our homes and businesses operate on an unrestricted demand. Simple monitoring and energy demand-ranking software can easily reduce peaks demands and move lower ranked uses to non-peak periods, thereby reducing the grid size needed to meet peak demands. Peak demand strains the current energy grid capacity and often requires demand balancing projects and

  8. Culture and cooperation in a spatial public goods game

    NASA Astrophysics Data System (ADS)

    Stivala, Alex; Kashima, Yoshihisa; Kirley, Michael

    2016-09-01

    We study the coevolution of culture and cooperation by combining the Axelrod model of cultural dissemination with a spatial public goods game, incorporating both noise and social influence. Both participation and cooperation in public goods games are conditional on cultural similarity. We find that a larger "scope of cultural possibilities" in the model leads to the survival of cooperation, when noise is not present, and a higher probability of a multicultural state evolving, for low noise rates. High noise rates, however, lead to both rapid extinction of cooperation and collapse into cultural "anomie," in which stable cultural regions fail to form. These results suggest that cultural diversity can actually be beneficial for the evolution of cooperation, but that cultural information needs to be transmitted accurately in order to maintain both coherent cultural groups and cooperation.

  9. Futures for energy cooperatives

    SciTech Connect

    1981-01-01

    A listing of Federal agencies and programs with potential funding for community-scale cooperatives using conservation measures and solar technologies is presented in Section 1. Section 2 presents profiles of existing community energy cooperatives describing their location, history, membership, services, sources of finance and technical assistance. A condensed summary from a recent conference on Energy Cooperatives featuring notes on co-op members' experiences, problems, and opportunities is presented in Section 3. Section 4 lists contacts for additional information. A National Consumer Cooperative Bank Load Application is shown in the appendix.

  10. DS-CDMA satellite diversity reception for personal satellite communication: Downlink performance analysis

    NASA Technical Reports Server (NTRS)

    DeGaudenzi, Riccardo; Giannetti, Filippo

    1995-01-01

    The downlink of a satellite-mobile personal communication system employing power-controlled Direct Sequence Code Division Multiple Access (DS-CDMA) and exploiting satellite-diversity is analyzed and its performance compared with a more traditional communication system utilizing single satellite reception. The analytical model developed has been thoroughly validated by means of extensive Monte Carlo computer simulations. It is shown how the capacity gain provided by diversity reception shrinks considerably in the presence of increasing traffic or in the case of light shadowing conditions. Moreover, the quantitative results tend to indicate that to combat system capacity reduction due to intra-system interference, no more than two satellites shall be active over the same region. To achieve higher system capacity, differently from terrestrial cellular systems, Multi-User Detection (MUD) techniques are likely to be required in the mobile user terminal, thus considerably increasing its complexity.

  11. Educational Cooperatives. PREP-23

    ERIC Educational Resources Information Center

    National Center for Educational Communication (DHEW/OE), Washington, DC.

    Dr. Larry W. Hughes and Dr. C. M. Achilles of the University of Tennessee, Knoxville, conducted a national survey for the Office of Education on educational cooperatives--studying and reporting on the nature and kind of cooperative endeavors, their organization, governance, financial arrangements, services, and personnel. Their study focused upon…

  12. Making Cooperative Learning Powerful

    ERIC Educational Resources Information Center

    Slavin, Robert E.

    2014-01-01

    Just about everyone loves the "idea" of cooperative learning, children working productively and excitedly in groups, everyone getting along and enthusiastically helping one another learn. This article presents five strategies that teachers can use to get the greatest benefit possible from cooperative learning and ensure that…

  13. Cooperative Science Lesson Plans.

    ERIC Educational Resources Information Center

    Cooperative Learning, 1991

    1991-01-01

    Offers several elementary level cooperative science lesson plans. The article includes a recipe for cooperative class learning, instructions for making a compost pile, directions for finding evidence of energy, experiments in math and science using oranges to test density, and discussions of buoyancy using eggs. (SM)

  14. Montana Cooperative Education Handbook.

    ERIC Educational Resources Information Center

    Harris, Ron, Ed.

    This revised handbook was developed to help teachers and administrators in Montana conduct cooperative education programs. The handbook is organized in 13 sections. In narrative style, the first 11 sections cover the following topics: introduction to cooperative education, advisory committees, related instruction, coordination of activities,…

  15. Cooperative Vocational Education Programs.

    ERIC Educational Resources Information Center

    Bureau of Adult, Vocational, and Technical Education (DHEW/OE), Washington, DC. Div. of Vocational and Technical Education.

    Cooperative education, said to be a "sleeping giant" in vocational education, received special authorization in Public Law 90 576 and was made a priority in vocational education. This publication summarizes information to assist the states in planning development of cooperative vocational education: definitions, funding sources, program content,…

  16. Evaluating Cooperative Education Programs.

    ERIC Educational Resources Information Center

    Alvir, Howard P.

    This document defines cooperative education as any form of occupational or professional activity that required the cooperation of both school and the labor market. In some cases, this might be the school and industry or business. In this process, evaluation is defined as the improvement of learner success through measurement of program components.…

  17. Cooperative Learning Strategies.

    ERIC Educational Resources Information Center

    Barnes, Buckley; O'Farrell, Gail

    1990-01-01

    Presents essential characteristics and types of cooperative learning strategies for use in elementary social studies. Outlines exercises for forming teams and building team spirit. Points out such methods promote group interdependence and student responsibility for learning and teaching others. Highlights two cooperative group strategies, Jigsaw…

  18. The cooperative brain.

    PubMed

    Stallen, Mirre; Sanfey, Alan G

    2013-06-01

    Cooperation is essential for the functioning of human societies. To better understand how cooperation both succeeds and fails, recent research in cognitive neuroscience has begun to explore novel paradigms to examine how cooperative mechanisms may be encoded in the brain. By combining functional neuroimaging techniques with simple but realistic tasks adapted from experimental economics, this approach allows for the discrimination and modeling of processes that are important in cooperative behavior. Here, we review evidence demonstrating that many of the processes underlying cooperation overlap with rather fundamental brain mechanisms, such as, for example, those involved in reward, punishment and learning. In addition, we review how social expectations induced by an interactive context and the experience of social emotions may influence cooperation and its associated underlying neural circuitry, and we describe factors that appear important for generating cooperation, such as the provision of incentives. These findings illustrate how cognitive neuroscience can contribute to the development of more accurate, brain-based, models of cooperative decision making.

  19. The cooperative brain.

    PubMed

    Stallen, Mirre; Sanfey, Alan G

    2013-06-01

    Cooperation is essential for the functioning of human societies. To better understand how cooperation both succeeds and fails, recent research in cognitive neuroscience has begun to explore novel paradigms to examine how cooperative mechanisms may be encoded in the brain. By combining functional neuroimaging techniques with simple but realistic tasks adapted from experimental economics, this approach allows for the discrimination and modeling of processes that are important in cooperative behavior. Here, we review evidence demonstrating that many of the processes underlying cooperation overlap with rather fundamental brain mechanisms, such as, for example, those involved in reward, punishment and learning. In addition, we review how social expectations induced by an interactive context and the experience of social emotions may influence cooperation and its associated underlying neural circuitry, and we describe factors that appear important for generating cooperation, such as the provision of incentives. These findings illustrate how cognitive neuroscience can contribute to the development of more accurate, brain-based, models of cooperative decision making. PMID:23300215

  20. Managing Cooperative Education.

    ERIC Educational Resources Information Center

    National Child Labor Committee, New York, NY.

    This manual presents concepts, tools, and techniques that are useful in the management of cooperative education programs at the state department of education, school district, and secondary school levels. Section I is a general discussion of the management role in cooperative education. In section II focus is on the nature of the internal and…

  1. Readings in Cooperative Education.

    ERIC Educational Resources Information Center

    Leventhal, Jerome I.

    Twenty-three journal articles on cooperative education were selected in a review of the literature by two Temple University graduate classes in the fall of 1975 and the spring of 1976 for those interested in the role of coordinating cooperative education programs. The journal readings consist of articles on theory/planning (6), implementation…

  2. Helping Children Cooperate

    ERIC Educational Resources Information Center

    Pica, Rae

    2011-01-01

    There are occasions in life when the competitive process is appropriate. But when people consider the relationships in their lives--with friends, family members, coworkers, and the larger community--they realize the value of cooperation. When adults give children the chance to cooperate, to work together toward a solution or a common goal like…

  3. Culture and cooperation

    PubMed Central

    Gächter, Simon; Herrmann, Benedikt; Thöni, Christian

    2010-01-01

    Does the cultural background influence the success with which genetically unrelated individuals cooperate in social dilemma situations? In this paper, we provide an answer by analysing the data of Herrmann et al. (2008a), who studied cooperation and punishment in 16 subject pools from six different world cultures (as classified by Inglehart & Baker (2000)). We use analysis of variance to disentangle the importance of cultural background relative to individual heterogeneity and group-level differences in cooperation. We find that culture has a substantial influence on the extent of cooperation, in addition to individual heterogeneity and group-level differences identified by previous research. The significance of this result is that cultural background has a substantial influence on cooperation in otherwise identical environments. This is particularly true in the presence of punishment opportunities. PMID:20679109

  4. Culture and cooperation.

    PubMed

    Gächter, Simon; Herrmann, Benedikt; Thöni, Christian

    2010-09-12

    Does the cultural background influence the success with which genetically unrelated individuals cooperate in social dilemma situations? In this paper, we provide an answer by analysing the data of Herrmann et al. (2008a), who studied cooperation and punishment in 16 subject pools from six different world cultures (as classified by Inglehart & Baker (2000)). We use analysis of variance to disentangle the importance of cultural background relative to individual heterogeneity and group-level differences in cooperation. We find that culture has a substantial influence on the extent of cooperation, in addition to individual heterogeneity and group-level differences identified by previous research. The significance of this result is that cultural background has a substantial influence on cooperation in otherwise identical environments. This is particularly true in the presence of punishment opportunities.

  5. Honoring Religion as a Source of Diversity and Unity

    ERIC Educational Resources Information Center

    Monsma, Stephen V.

    2005-01-01

    Unity without diversity is, at best, boring, and at worse, totalitarian. Diversity without unity constantly threatens to degenerate, at best, into tensions and failures at cooperation and, at worst, into genocide. The sources of diversity in the United States are many. Racial and ethnic differences as well as differences based on national origins,…

  6. Persistent cooperators in nature.

    PubMed

    Liu, Xinsheng; Guo, Wanlin

    2010-12-21

    The evolution and maintenance of cooperation fascinated researchers for several decades. Recently, theoretical models and experimental evidence show that costly punishment may facilitate cooperation in human societies. The puzzle how the costly punishment behaviour evolves can be solved under voluntary participation. Could the punishers emerge if participation is compulsory? Is the punishment inevitably a selfish behaviour or an altruistic behaviour? The motivations behind punishment are still an enigma. Based on public goods interactions, we present a model in which just a certain portion of the public good is divided equally among all members. The other portion is distributed to contributors when paying a second cost. The contributors who are willing to pay a second cost are called the persistent cooperators (PC), indicating their desire to retrieve the proportion of the payoff derived from their own contributions with persistent efforts. We show that the persistent cooperators can be costly punishers, which may account for the origin of human costly punishment behaviour under compulsory participation. In this sense our models may show theoretically that the original motivation behind punishment is to retrieve deserved payoff from their own contributions, a selfish incentive. But the persistent cooperators can also flourish or dominate the population in other situations. We list many real examples in which contributors are the persistent cooperators, and they benefit. This indicates a simple norm promoting cooperation: contributing more and gaining more.

  7. Globalization and human cooperation.

    PubMed

    Buchan, Nancy R; Grimalda, Gianluca; Wilson, Rick; Brewer, Marilynn; Fatas, Enrique; Foddy, Margaret

    2009-03-17

    Globalization magnifies the problems that affect all people and that require large-scale human cooperation, for example, the overharvesting of natural resources and human-induced global warming. However, what does globalization imply for the cooperation needed to address such global social dilemmas? Two competing hypotheses are offered. One hypothesis is that globalization prompts reactionary movements that reinforce parochial distinctions among people. Large-scale cooperation then focuses on favoring one's own ethnic, racial, or language group. The alternative hypothesis suggests that globalization strengthens cosmopolitan attitudes by weakening the relevance of ethnicity, locality, or nationhood as sources of identification. In essence, globalization, the increasing interconnectedness of people worldwide, broadens the group boundaries within which individuals perceive they belong. We test these hypotheses by measuring globalization at both the country and individual levels and analyzing the relationship between globalization and individual cooperation with distal others in multilevel sequential cooperation experiments in which players can contribute to individual, local, and/or global accounts. Our samples were drawn from the general populations of the United States, Italy, Russia, Argentina, South Africa, and Iran. We find that as country and individual levels of globalization increase, so too does individual cooperation at the global level vis-à-vis the local level. In essence, "globalized" individuals draw broader group boundaries than others, eschewing parochial motivations in favor of cosmopolitan ones. Globalization may thus be fundamental in shaping contemporary large-scale cooperation and may be a positive force toward the provision of global public goods. PMID:19255433

  8. Network modularity promotes cooperation.

    PubMed

    Marcoux, Marianne; Lusseau, David

    2013-05-01

    Cooperation in animals and humans is widely observed even if evolutionary biology theories predict the evolution of selfish individuals. Previous game theory models have shown that cooperation can evolve when the game takes place in a structured population such as a social network because it limits interactions between individuals. Modularity, the natural division of a network into groups, is a key characteristic of all social networks but the influence of this crucial social feature on the evolution of cooperation has never been investigated. Here, we provide novel pieces of evidence that network modularity promotes the evolution of cooperation in 2-person prisoner's dilemma games. By simulating games on social networks of different structures, we show that modularity shapes interactions between individuals favouring the evolution of cooperation. Modularity provides a simple mechanism for the evolution of cooperation without having to invoke complicated mechanisms such as reputation or punishment, or requiring genetic similarity among individuals. Thus, cooperation can evolve over wider social contexts than previously reported.

  9. Globalization and human cooperation.

    PubMed

    Buchan, Nancy R; Grimalda, Gianluca; Wilson, Rick; Brewer, Marilynn; Fatas, Enrique; Foddy, Margaret

    2009-03-17

    Globalization magnifies the problems that affect all people and that require large-scale human cooperation, for example, the overharvesting of natural resources and human-induced global warming. However, what does globalization imply for the cooperation needed to address such global social dilemmas? Two competing hypotheses are offered. One hypothesis is that globalization prompts reactionary movements that reinforce parochial distinctions among people. Large-scale cooperation then focuses on favoring one's own ethnic, racial, or language group. The alternative hypothesis suggests that globalization strengthens cosmopolitan attitudes by weakening the relevance of ethnicity, locality, or nationhood as sources of identification. In essence, globalization, the increasing interconnectedness of people worldwide, broadens the group boundaries within which individuals perceive they belong. We test these hypotheses by measuring globalization at both the country and individual levels and analyzing the relationship between globalization and individual cooperation with distal others in multilevel sequential cooperation experiments in which players can contribute to individual, local, and/or global accounts. Our samples were drawn from the general populations of the United States, Italy, Russia, Argentina, South Africa, and Iran. We find that as country and individual levels of globalization increase, so too does individual cooperation at the global level vis-à-vis the local level. In essence, "globalized" individuals draw broader group boundaries than others, eschewing parochial motivations in favor of cosmopolitan ones. Globalization may thus be fundamental in shaping contemporary large-scale cooperation and may be a positive force toward the provision of global public goods.

  10. Cooperative Learning Strategies.

    ERIC Educational Resources Information Center

    Pratt, Sandra

    2003-01-01

    Describes the effectiveness of cooperative learning on discipline problems, interdependence between students, and teacher-student interactions. Explains how to group students and introduces a laboratory activity on covalent and ionic bonds. (YDS)

  11. Cooperative processing data bases

    NASA Technical Reports Server (NTRS)

    Hasta, Juzar

    1991-01-01

    Cooperative processing for the 1990's using client-server technology is addressed. The main theme is concepts of downsizing from mainframes and minicomputers to workstations on a local area network (LAN). This document is presented in view graph form.

  12. Cooperative Education: Industry Involvement.

    ERIC Educational Resources Information Center

    Davies, Geoffrey; McClelland, Alan L.

    1980-01-01

    Contains information from three large chemical companies having a long-standing interest in cooperative education with chemistry students. Questions and answers are provided for specific information regarding DuPont, 3M, and Dow Chemical. (CS)

  13. How Myxobacteria Cooperate.

    PubMed

    Cao, Pengbo; Dey, Arup; Vassallo, Christopher N; Wall, Daniel

    2015-11-20

    Prokaryotes often reside in groups where a high degree of relatedness has allowed the evolution of cooperative behaviors. However, very few bacteria or archaea have made the successful transition from unicellular to obligate multicellular life. A notable exception is the myxobacteria, in which cells cooperate to perform group functions highlighted by fruiting body development, an obligate multicellular function. Like all multicellular organisms, myxobacteria face challenges in how to organize and maintain multicellularity. These challenges include maintaining population homeostasis, carrying out tissue repair and regulating the behavior of non-cooperators. Here, we describe the major cooperative behaviors that myxobacteria use: motility, predation and development. In addition, this review emphasizes recent discoveries in the social behavior of outer membrane exchange, wherein kin share outer membrane contents. Finally, we review evidence that outer membrane exchange may be involved in regulating population homeostasis, thus serving as a social tool for myxobacteria to make the cyclic transitions from unicellular to multicellular states. PMID:26254571

  14. Cooperative Education Abroad.

    ERIC Educational Resources Information Center

    Knowles, Asa S.

    1978-01-01

    Although cooperative education may be uniquely American, other nations place great importance on relating work and education. Types of programs, calendars and schedules are reviewed, and global patterns are described. (Author/LBH)

  15. Cooperative Learning in Statistics.

    ERIC Educational Resources Information Center

    Keeler, Carolyn M.; And Others

    1994-01-01

    Formal use of cooperative learning techniques proved effective in improving student performance and retention in a freshman level statistics course. Lectures interspersed with group activities proved effective in increasing conceptual understanding and overall class performance. (11 references) (Author)

  16. Cooperating mobile robots

    DOEpatents

    Harrington, John J.; Eskridge, Steven E.; Hurtado, John E.; Byrne, Raymond H.

    2004-02-03

    A miniature mobile robot provides a relatively inexpensive mobile robot. A mobile robot for searching an area provides a way for multiple mobile robots in cooperating teams. A robotic system with a team of mobile robots communicating information among each other provides a way to locate a source in cooperation. A mobile robot with a sensor, a communication system, and a processor, provides a way to execute a strategy for searching an area.

  17. Social Stratification and Cooperative Behavior in Spatial Prisoners' Dilemma Games

    PubMed Central

    Lu, Peng; Zheng, Xiaoping

    2015-01-01

    It has been a long-lasting pursuit to promote cooperation, and this study aims to promote cooperation via the combination of social stratification and the spatial prisoners’ dilemma game. It is previously assumed that agents share the identical payoff matrix, but the stratification or diversity exists and exerts influences in real societies. Thus, two additional classes, elites and scoundrels, derive from and coexist with the existing class, commons. Three classes have different payoff matrices. We construct a model where agents play the prisoners’ dilemma game with neighbors. It indicates that stratification and temptation jointly influence cooperation. Temptation permanently reduces cooperation; elites play a positive role in promoting cooperation while scoundrels undermine it. As the temptation getting larger and larger, elites play a more and more positive and critical role while scoundrels’ negative effect becomes weaker and weaker, and it is more obvious when temptation goes beyond its threshold. PMID:26173029

  18. Social Stratification and Cooperative Behavior in Spatial Prisoners' Dilemma Games.

    PubMed

    Lu, Peng; Zheng, Xiaoping

    2015-01-01

    It has been a long-lasting pursuit to promote cooperation, and this study aims to promote cooperation via the combination of social stratification and the spatial prisoners' dilemma game. It is previously assumed that agents share the identical payoff matrix, but the stratification or diversity exists and exerts influences in real societies. Thus, two additional classes, elites and scoundrels, derive from and coexist with the existing class, commons. Three classes have different payoff matrices. We construct a model where agents play the prisoners' dilemma game with neighbors. It indicates that stratification and temptation jointly influence cooperation. Temptation permanently reduces cooperation; elites play a positive role in promoting cooperation while scoundrels undermine it. As the temptation getting larger and larger, elites play a more and more positive and critical role while scoundrels' negative effect becomes weaker and weaker, and it is more obvious when temptation goes beyond its threshold. PMID:26173029

  19. Social Stratification and Cooperative Behavior in Spatial Prisoners' Dilemma Games.

    PubMed

    Lu, Peng; Zheng, Xiaoping

    2015-01-01

    It has been a long-lasting pursuit to promote cooperation, and this study aims to promote cooperation via the combination of social stratification and the spatial prisoners' dilemma game. It is previously assumed that agents share the identical payoff matrix, but the stratification or diversity exists and exerts influences in real societies. Thus, two additional classes, elites and scoundrels, derive from and coexist with the existing class, commons. Three classes have different payoff matrices. We construct a model where agents play the prisoners' dilemma game with neighbors. It indicates that stratification and temptation jointly influence cooperation. Temptation permanently reduces cooperation; elites play a positive role in promoting cooperation while scoundrels undermine it. As the temptation getting larger and larger, elites play a more and more positive and critical role while scoundrels' negative effect becomes weaker and weaker, and it is more obvious when temptation goes beyond its threshold.

  20. Supramolecular assemblies of tetrafluoroterephthalic acid and N-heterocycles via various strong hydrogen bonds and weak Csbnd H⋯F interactions: Synthons cooperation, robust motifs and structural diversity

    NASA Astrophysics Data System (ADS)

    Hu, Yanjing; Hu, Hanbin; Li, Yingying; Chen, Ruixin; Yang, Yu; Wang, Lei

    2016-10-01

    A series of organic solid states including three salts, two co-crystals, and three hydrates based on tetrafluoroterephthalic acid (H2tfBDC) and N-bearing ligands (2,4-(1H,3H)-pyrimidine dione (PID), 2,4-dihydroxy-6-methyl pyrimidine (DHMPI), 2-amino-4,6-dimethyl pyrimidine (ADMPI), 2-amino-4,6-dimenthoxy pyrimidine (ADMOPI), 5,6-dimenthyl benzimidazole (DMBI), 2-aminobenzimidazole (ABI), 3,5-dimethyl pyrazole (DMP), and 3-cyanopyridine (3-CNpy)), namely, [(PID)2·(H2tfBDC)] (1), [(DHMPI)2·(H2tfBDC)] (2), [(H-ADMPI+)2·(tfBDC2-)·2(H2O)] (3), [(H-ADMOPI+)2·(tfBDC2-)·(H2O)] (4), [(H-DMBI+)2·(tfBDC2-)·2(H2O)] (5), [(H-ABI+)2·(tfBDC2-)] (6), [(H-DMP+)·(HtfBDC-)] (7), and [(H-3-CNpy+)·(HtfBDC-)] (8), were synthesized by solvent evaporation method. Crystal structures analyses show that the F atom of the H2tfBDC participates in multiple Csbnd H⋯F hydrogen bond formations, producing different supramolecular synthons. The weak hydrogen bonding Csbnd H⋯F and Nsbnd H⋯F play an important part in constructing the diversity structures 2-8, except in crystal 1. In complexes 1-3, they present the same synthon R22(8) with different N-heterocyclic compounds, which may show the strategy in constructing the supramolecular. Meanwhile, the complex 3 exhibits a 2D layer, and the independent molecules of water exist in the adjacent layers. In complexes 4 and 5, the water molecules connect the neighboring layers to form 3D network by strong Osbnd H⋯O hydrogen bonding. These crystals 1-8 were fully characterized by single-crystal X-ray crystallography, elemental analysis, infrared spectroscopy (IR), and thermogravimetric analysis (TGA).

  1. Theme: Supporting Professional Diversity.

    ERIC Educational Resources Information Center

    Moore, Eddie A.; And Others

    1994-01-01

    Includes "Supporting Diversity" (Moore); "Reflections on the Need for Diversity" (Bowen); "Understanding Impediments to Diversity in Agricultural Education" (Whent); "Mentoring Diverse Populations" (Jones); "Supporting Diversity: An Unfinished Agenda" (Moore); "Professorial Roles in Supporting Diversity in Teaching, Research, and University…

  2. International Cooperation at NASA

    NASA Astrophysics Data System (ADS)

    Tawney, Timothy; Feldstein, Karen

    International cooperation is a cornerstone principle of NASA’s activities, especially within the activities of the Science Mission Directorate. Nearly two thirds of the flight missions in which NASA leads or participates involve international cooperation. Numerous ground based activities also rely on international cooperation, whether because of unique expertise, unique geography, or the need for a global response. Going forward, in an era of tighter budgets and a more integrated global perspective, NASA and the rest of the space agencies around the world will be forced to work more closely together, in a broader array of activities than ever before, in order to be able to afford to push the boundaries of space exploration. The goal of this presentation is to provide an overview of NASA’s current international science cooperative activities. It will include a discussion of why NASA conducts international cooperation and look at the mechanisms through which international cooperation can occur at NASA, including peer-to-peer development of relationships. It will also discuss some of the limiting factors of international cooperation, such as export control, and ways in which to manage those constraints. Finally, the presentation would look at some of the present examples where NASA is working to increase international cooperation and improve coordination. Case studies will be used to demonstrate these mechanisms and concepts. For example, NASA continues to participate in international coordination groups such as the International Mars Exploration Working Group (IMEWG) and International Space Exploration Coordination Group (ISECG), but is expanding into new areas as well. NASA is one of the leaders in expanding and improving international coordination in the area of Near-Earth Object detection, characterization, and mitigation. Having participated in the first meetings of such groups as the International Asteroid Warning Network (IAWN) and Space Missions Planning

  3. Cooper Pair Insulators

    NASA Astrophysics Data System (ADS)

    Valles, James

    One of the recent advances in the field of the Superconductor to Insulator Transition (SIT) has been the discovery and characterization of the Cooper Pair Insulator phase. This bosonic insulator, which consists of localized Cooper pairs, exhibits activated transport and a giant magneto-resistance peak. These features differ markedly from the weakly localized transport that emerges as pairs break at a ``fermionic'' SIT. I will describe how our experiments on films nano-patterned with a nearly triangular array of holes have enabled us to 1) distinguish bosonic insulators from fermionic insulators, 2) show that Cooper pairs, rather than quasi-particles dominate the transport in the Cooper Pair insulator phase, 3) demonstrate that very weak, sub nano-meter thickness inhomogeneities control whether a bosonic or fermionic insulator forms at an SIT and 4) reveal that Cooper pairs disintegrate rather than becoming more tightly bound deep in the localized phase. We have also developed a method, using a magnetic field, to tune flux disorder reversibly in these films. I will present our latest results on the influence of magnetic flux disorder and random gauge fields on phenomena near bosonic SITs. This work was performed in collaboration with M. D. Stewart, Jr., Hung Q. Nguyen, Shawna M. Hollen, Jimmy Joy, Xue Zhang, Gustavo Fernandez, Jeffrey Shainline and Jimmy Xu. It was supported by NSF Grants DMR 1307290 and DMR-0907357.

  4. Cooper Pairs in Insulators?!

    SciTech Connect

    James Valles

    2008-07-23

    Nearly 50 years elapsed between the discovery of superconductivity and the emergence of the microscopic theory describing this zero resistance state. The explanation required a novel phase of matter in which conduction electrons joined in weakly bound pairs and condensed with other pairs into a single quantum state. Surprisingly, this Cooper pair formation has also been invoked to account for recently uncovered high-resistance or insulating phases of matter. To address this possibility, we have used nanotechnology to create an insulating system that we can probe directly for Cooper pairs. I will present the evidence that Cooper pairs exist and dominate the electrical transport in these insulators and I will discuss how these findings provide new insight into superconductor to insulator quantum phase transitions. 

  5. Cooper Pairs in Insulators?!

    ScienceCinema

    James Valles

    2016-07-12

    Nearly 50 years elapsed between the discovery of superconductivity and the emergence of the microscopic theory describing this zero resistance state. The explanation required a novel phase of matter in which conduction electrons joined in weakly bound pairs and condensed with other pairs into a single quantum state. Surprisingly, this Cooper pair formation has also been invoked to account for recently uncovered high-resistance or insulating phases of matter. To address this possibility, we have used nanotechnology to create an insulating system that we can probe directly for Cooper pairs. I will present the evidence that Cooper pairs exist and dominate the electrical transport in these insulators and I will discuss how these findings provide new insight into superconductor to insulator quantum phase transitions. 

  6. Neural basis of conditional cooperation.

    PubMed

    Suzuki, Shinsuke; Niki, Kazuhisa; Fujisaki, Syoken; Akiyama, Eizo

    2011-06-01

    Cooperation among genetically unrelated individuals is a fundamental aspect of society, but it has been a longstanding puzzle in biological and social sciences. Recently, theoretical studies in biology and economics showed that conditional cooperation-cooperating only with those who have exhibited cooperative behavior-can spread over a society. Furthermore, experimental studies in psychology demonstrated that people are actually conditional cooperators. In this study, we used functional magnetic resonance imaging to investigate the neural system underlying conditional cooperation by scanning participants during interaction with cooperative, neutral and non-cooperative opponents in prisoner's dilemma games. The results showed that: (i) participants cooperated more frequently with both cooperative and neutral opponents than with non-cooperative opponents; and (ii) a brain area related to cognitive inhibition of pre-potent responses (right dorsolateral prefrontal cortex) showed greater activation, especially when participants confronted non-cooperative opponents. Consequently, we suggest that cognitive inhibition of the motivation to cooperate with non-cooperators drives the conditional behavior.

  7. Social penalty promotes cooperation in a cooperative society.

    PubMed

    Ito, Hiromu; Yoshimura, Jin

    2015-01-01

    Why cooperation is well developed in human society is an unsolved question in biological and human sciences. Vast studies in game theory have revealed that in non-cooperative games selfish behavior generally dominates over cooperation and cooperation can be evolved only under very limited conditions. These studies ask the origin of cooperation; whether cooperation can evolve in a group of selfish individuals. In this paper, instead of asking the origin of cooperation, we consider the enhancement of cooperation in a small already cooperative society. We ask whether cooperative behavior is further promoted in a small cooperative society in which social penalty is devised. We analyze hawk-dove game and prisoner's dilemma introducing social penalty. We then expand it for non-cooperative games in general. The results indicate that cooperation is universally favored if penalty is further imposed. We discuss the current result in terms of the moral, laws, rules and regulations in a society, e.g., criminology and traffic violation. PMID:26238521

  8. Social penalty promotes cooperation in a cooperative society.

    PubMed

    Ito, Hiromu; Yoshimura, Jin

    2015-08-04

    Why cooperation is well developed in human society is an unsolved question in biological and human sciences. Vast studies in game theory have revealed that in non-cooperative games selfish behavior generally dominates over cooperation and cooperation can be evolved only under very limited conditions. These studies ask the origin of cooperation; whether cooperation can evolve in a group of selfish individuals. In this paper, instead of asking the origin of cooperation, we consider the enhancement of cooperation in a small already cooperative society. We ask whether cooperative behavior is further promoted in a small cooperative society in which social penalty is devised. We analyze hawk-dove game and prisoner's dilemma introducing social penalty. We then expand it for non-cooperative games in general. The results indicate that cooperation is universally favored if penalty is further imposed. We discuss the current result in terms of the moral, laws, rules and regulations in a society, e.g., criminology and traffic violation.

  9. Social penalty promotes cooperation in a cooperative society

    PubMed Central

    Ito, Hiromu; Yoshimura, Jin

    2015-01-01

    Why cooperation is well developed in human society is an unsolved question in biological and human sciences. Vast studies in game theory have revealed that in non-cooperative games selfish behavior generally dominates over cooperation and cooperation can be evolved only under very limited conditions. These studies ask the origin of cooperation; whether cooperation can evolve in a group of selfish individuals. In this paper, instead of asking the origin of cooperation, we consider the enhancement of cooperation in a small already cooperative society. We ask whether cooperative behavior is further promoted in a small cooperative society in which social penalty is devised. We analyze hawk-dove game and prisoner’s dilemma introducing social penalty. We then expand it for non-cooperative games in general. The results indicate that cooperation is universally favored if penalty is further imposed. We discuss the current result in terms of the moral, laws, rules and regulations in a society, e.g., criminology and traffic violation. PMID:26238521

  10. Generational diversity.

    PubMed

    Kramer, Linda W

    2010-01-01

    Generational diversity has proven challenges for nurse leaders, and generational values may influence ideas about work and career planning. This article discusses generational gaps, influencing factors and support, and the various generational groups present in today's workplace as well as the consequences of need addressing these issues. The article ends with a discussion of possible solutions.

  11. Generational diversity.

    PubMed

    Kramer, Linda W

    2010-01-01

    Generational diversity has proven challenges for nurse leaders, and generational values may influence ideas about work and career planning. This article discusses generational gaps, influencing factors and support, and the various generational groups present in today's workplace as well as the consequences of need addressing these issues. The article ends with a discussion of possible solutions. PMID:20395729

  12. Diversity Trailblazer

    ERIC Educational Resources Information Center

    Stuart, Reginald

    2012-01-01

    When Dr. Kumea Shorter-Gooden took on her newly created job this month at the University of Maryland's flagship College Park campus, she assumed a challenge at the school with a lot riding on her shoulders--helping the University of Maryland strengthen its diversity efforts and, thus, its relevance to the state in the future and standing among the…

  13. PLANT DIVERSITY

    EPA Science Inventory

    Habitat change statistics and species-area curves were used to estimate the effects of alternative future scenarios for agriculture on plant diversity in Iowa farmlands. Study areas were two watersheds in central Iowa of about 50 and 90 square kilometers, respectively. Future s...

  14. The Power of Cooperation

    ERIC Educational Resources Information Center

    Nevin, John A.

    2010-01-01

    In "The Power of Cooperation," Tony Nevin tells how the townspeople of Martha's Vineyard, Massachusetts, are attempting to replicate a successful alternative-energy project in Samso, Denmark, where thinking about ways to reduce fossil-fuel use "became a kind of sport." Nevin says that thinking and acting locally helps people to identify and pursue…

  15. Cooperative Education. Final Report.

    ERIC Educational Resources Information Center

    Stauber, Dick T.

    In order to investigate the feasibility of adding a cooperative education option to the curricular offerings of Moraine Park Technical Institute (MPTI), interviews were conducted with randomly selected representatives of 12 industries and 17 employers in the marketing and merchandising businesses located in the MPTI service area. In addition,…

  16. Superpower cooperation often overlooked

    SciTech Connect

    Jamgotch, N. Jr.

    1986-02-01

    At the conclusion of the Geneva summit in November 1985, President Reagan and General Secretary Gorbachev signed an Agreement on Contacts and Exchanges in Scientific, Educational, and Cultural Fields. Since details of the agreements must still be worked out, it remains to be seen whether these statements signal a new era of US-Soviet cooperation. Still, the lack of media or even official attention to these broad areas of agreement repeats a pattern that has contributed to the continuing pervasive hostility and mistrust between the two nations. There are understandable reasons for the tendency to concentrate on conflict and crises rather than cooperation. While a cooperative agreement may be noted by an occasional news story, it is outshone be the more flash newsworthiness of political confrontation. The author points to the considerable successes of past US/USSR wide-ranging agreements, and notes that cooperative activities must be reported and analyzed more fully to counteract distrust and to overcome outmoded ideologies. 6 references.

  17. Cooperative Mobile Sensing Networks

    SciTech Connect

    Roberts, R S; Kent, C A; Jones, E D; Cunningham, C T; Armstrong, G W

    2003-02-10

    A cooperative control architecture is presented that allows a fleet of Unmanned Air Vehicles (UAVs) to collect data in a parallel, coordinated and optimal manner. The architecture is designed to react to a set of unpredictable events thereby allowing data collection to continue in an optimal manner.

  18. Combat or Cooperation?

    ERIC Educational Resources Information Center

    Tate, Thomas F.; Copas, Randall L.

    2010-01-01

    The best intentioned efforts of adults are often sabotaged by coercive climates of bullying among peers and conflict with adults. The solution is to create cultures where youth cooperate with authority and treat one another with respect. In this article, the authors stress the task of the staff to create a condition in which students see more…

  19. Cooperative Learning and Teaching

    ERIC Educational Resources Information Center

    Jacobs, G. M.; Kimura, H.

    2013-01-01

    In and out of the classroom, life would be unthinkable without interacting with fellow humans. This book urges more cooperative and group activities in the English language classroom for all the advantages: students use the target language more, help each other with comprehension, receive attention from peers as well as the teacher, are motivated…

  20. International Cooperation in Engineering.

    ERIC Educational Resources Information Center

    Willenbrock, F. Karl

    1987-01-01

    Reports on a study by the National Academy of Engineering (NAE) into various relationships in engineering that the United States has with countries that have comparable or superior levels of technology. Discusses competition, cooperation, information flow, symmetry, language and cultural barriers, research opportunities, and professional…

  1. Cooper Egressing 'Faith 7'

    NASA Technical Reports Server (NTRS)

    1963-01-01

    Astronaut L. Gordon Cooper is assisted in backing out of his Mecury capsule 'Faith 7' after a 600,000 mile, 22.9 orbit journey around the Earth. He elected to remain in the spacecraft until it was hoisted to the deck of the Kearsarge, as did Astronaut Walter Schirra during the previous mission.

  2. To Cooperate or Not to Cooperate: Why Behavioural Mechanisms Matter

    PubMed Central

    2016-01-01

    Mutualistic cooperation often requires multiple individuals to behave in a coordinated fashion. Hence, while the evolutionary stability of mutualistic cooperation poses no particular theoretical difficulty, its evolutionary emergence faces a chicken and egg problem: an individual cannot benefit from cooperating unless other individuals already do so. Here, we use evolutionary robotic simulations to study the consequences of this problem for the evolution of cooperation. In contrast with standard game-theoretic results, we find that the transition from solitary to cooperative strategies is very unlikely, whether interacting individuals are genetically related (cooperation evolves in 20% of all simulations) or unrelated (only 3% of all simulations). We also observe that successful cooperation between individuals requires the evolution of a specific and rather complex behaviour. This behavioural complexity creates a large fitness valley between solitary and cooperative strategies, making the evolutionary transition difficult. These results reveal the need for research on biological mechanisms which may facilitate this transition. PMID:27148874

  3. Twelve Propositions on Diversity in Higher Education

    ERIC Educational Resources Information Center

    Codling, Andrew; Meek, Lynn V.

    2006-01-01

    This paper explores the relationship between the diversity within a higher education system and five key factors, namely: the environment, policy intervention, funding, competition and co-operation, and ranking. The exploration is based on the extent to which higher education systems, particularly those of Australia and New Zealand, have…

  4. [Social cooperatives in Italy].

    PubMed

    Villotti, P; Zaniboni, S; Fraccaroli, F

    2014-06-01

    This paper describes the role of social cooperatives in Italy as a type of economic, non-profit organization and their role in contributing to the economic and social growth of the country. The purpose of this paper is to learn more about the experience of the Italian social cooperatives in promoting the work integration process of disadvantaged workers, especially those suffering from mental disorders, from a theoretical and an empirical point of view. Social enterprise is the most popular and consolidated legal and organizational model for social enterprises in Italy, introduced by Law 381/91. Developed during the early 1980s, and formally recognized by law in the early 1990s, social cooperatives aim at pursuing the general interest of the community to promote the human needs and social inclusion of citizens. They are orientated towards aims that go beyond the interest of the business owners, the primary beneficiary of their activities is the community, or groups of disadvantaged people. In Italy, Law 381/91 distinguishes between two categories of social cooperatives, those producing goods of social utility, such as culture, welfare and educational services (A-type), and those providing economic activities for the integration of disadvantaged people into employment (B-type). The main purpose of B-type social cooperatives is to integrate disadvantaged people into the open labour market. This goal is reached after a period of training and working experience inside the firm, during which the staff works to improve both the social and professional abilities of disadvantaged people. During the years, B-type social co-ops acquired a particular relevance in the care of people with mental disorders by offering them with job opportunities. Having a job is central in the recovery process of people suffering from mental diseases, meaning that B-type social co-ops in Italy play an important rehabilitative and integrative role for this vulnerable population of workers. The

  5. [Social cooperatives in Italy].

    PubMed

    Villotti, P; Zaniboni, S; Fraccaroli, F

    2014-06-01

    This paper describes the role of social cooperatives in Italy as a type of economic, non-profit organization and their role in contributing to the economic and social growth of the country. The purpose of this paper is to learn more about the experience of the Italian social cooperatives in promoting the work integration process of disadvantaged workers, especially those suffering from mental disorders, from a theoretical and an empirical point of view. Social enterprise is the most popular and consolidated legal and organizational model for social enterprises in Italy, introduced by Law 381/91. Developed during the early 1980s, and formally recognized by law in the early 1990s, social cooperatives aim at pursuing the general interest of the community to promote the human needs and social inclusion of citizens. They are orientated towards aims that go beyond the interest of the business owners, the primary beneficiary of their activities is the community, or groups of disadvantaged people. In Italy, Law 381/91 distinguishes between two categories of social cooperatives, those producing goods of social utility, such as culture, welfare and educational services (A-type), and those providing economic activities for the integration of disadvantaged people into employment (B-type). The main purpose of B-type social cooperatives is to integrate disadvantaged people into the open labour market. This goal is reached after a period of training and working experience inside the firm, during which the staff works to improve both the social and professional abilities of disadvantaged people. During the years, B-type social co-ops acquired a particular relevance in the care of people with mental disorders by offering them with job opportunities. Having a job is central in the recovery process of people suffering from mental diseases, meaning that B-type social co-ops in Italy play an important rehabilitative and integrative role for this vulnerable population of workers. The

  6. Neural basis of conditional cooperation

    PubMed Central

    Niki, Kazuhisa; Fujisaki, Syoken; Akiyama, Eizo

    2011-01-01

    Cooperation among genetically unrelated individuals is a fundamental aspect of society, but it has been a longstanding puzzle in biological and social sciences. Recently, theoretical studies in biology and economics showed that conditional cooperation—cooperating only with those who have exhibited cooperative behavior—can spread over a society. Furthermore, experimental studies in psychology demonstrated that people are actually conditional cooperators. In this study, we used functional magnetic resonance imaging to investigate the neural system underlying conditional cooperation by scanning participants during interaction with cooperative, neutral and non-cooperative opponents in prisoner's dilemma games. The results showed that: (i) participants cooperated more frequently with both cooperative and neutral opponents than with non-cooperative opponents; and (ii) a brain area related to cognitive inhibition of pre-potent responses (right dorsolateral prefrontal cortex) showed greater activation, especially when participants confronted non-cooperative opponents. Consequently, we suggest that cognitive inhibition of the motivation to cooperate with non-cooperators drives the conditional behavior. PMID:20501484

  7. A Course of Study in Cooperation and Cooperatives.

    ERIC Educational Resources Information Center

    Bjoraker, Walter T., Ed.

    Designed for teachers with limited experience in cooperatives, this course of study was prepared by seminar students for use in high school or adult education programs, and emphasizes the principles of cooperation, the operation and management of cooperatives, and the communication required for their effective functioning. Units requiring a total…

  8. Cooperation and cheating in microbes

    NASA Astrophysics Data System (ADS)

    Gore, Jeff

    2011-03-01

    Understanding the cooperative and competitive dynamics within and between species is a central challenge in evolutionary biology. Microbial model systems represent a unique opportunity to experimentally test fundamental theories regarding the evolution of cooperative behaviors. In this talk I will describe our experiments probing cooperation in microbes. In particular, I will compare the cooperative growth of yeast in sucrose and the cooperative inactivation of antibiotics by bacteria. In both cases we find that cheater strains---which don't contribute to the public welfare---are able to take advantage of the cooperator strains. However, this ability of cheaters to out-compete cooperators occurs only when cheaters are present at low frequency, thus leading to steady-state coexistence. These microbial experiments provide fresh insight into the evolutionary origin of cooperation.

  9. Cultural Diversity in Classrooms: What Teachers Need To Know.

    ERIC Educational Resources Information Center

    Sandhu, Daya Singh

    This paper emphasizes the significance of cultural diversity in American schools and its implications for the teaching and learning processes. Also highlighted is the importance of the realization that diversity is what makes the United States unique. The paper discusses the cultural dynamics of clashes and conflicts as well as of cooperation and…

  10. Managing diversity.

    PubMed

    Wagner, M

    1991-09-30

    One look at projections for the U.S. work force through the year 2000 shows why healthcare administrators will be facing some new challenges. With the majority of new workers belonging to minority groups, "managing diversity" has become the newest catch phrase as executives work to reduce tensions resulting from race, gender or culture-based differences among workers, while also learning to understand and value those differences.

  11. An Odyssey into Cooperative Learning.

    ERIC Educational Resources Information Center

    Lemke, Thomas L.; Basile, Carole

    1997-01-01

    An experiment using cooperative learning in a introductory pharmacy course in medicinal chemistry revealed general acceptance of the cooperative learning approach by students, and some perceived advantages for both students and teachers. Although quantitative evidence supporting superiority of the cooperative learning approach was not found,…

  12. Cooperative Learning for LEP Students.

    ERIC Educational Resources Information Center

    Calderon, Margarita

    1989-01-01

    Substantial evidence suggests that students working together in small cooperative groups can master material better than students working on their own, and that cooperative learning structures higher self-esteem and learning motivation. Cooperative learning (CL) has been proposed for use with language minority children, as well as with other…

  13. Enlightening Advantages of Cooperative Learning

    ERIC Educational Resources Information Center

    Faryadi, Qais

    2007-01-01

    This appraisal discusses the notion that cooperative learning enhances learners' emotional and social performance. It also observes the perception that cooperative learning dramatically improves students' academic accomplishment. This review also examines the definition of cooperative learning and attempts to define it through the lens of renowned…

  14. Communication in Cooperative Learning Groups.

    ERIC Educational Resources Information Center

    Kalkowski, Page

    This study explores aspects of the hypothesis that communication in cooperative learning groups mediates effects of cooperative learning. The study develops a taxonomy of the cooperative communications of groups of predominantly Anglo and Hispanic elementary school students attending a public school where teachers were being trained to implement…

  15. Cooperative Learning in Elementary Schools

    ERIC Educational Resources Information Center

    Slavin, Robert E.

    2015-01-01

    Cooperative learning refers to instructional methods in which students work in small groups to help each other learn. Although cooperative learning methods are used for different age groups, they are particularly popular in elementary (primary) schools. This article discusses methods and theoretical perspectives on cooperative learning for the…

  16. Cooperative Learning: Developments in Research

    ERIC Educational Resources Information Center

    Gillies, Robyn M.

    2014-01-01

    Cooperative learning is widely recognized as a pedagogical practice that promotes socialization and learning among students from kindergarten through to college level and across different subject areas. Cooperative learning involves students working together to achieve common goals or complete group tasks. Interest in cooperative learning has…

  17. International Cooperation: A Positive Response.

    ERIC Educational Resources Information Center

    Soria, Oscar

    Conditions for developing international university cooperation are identified, along with stages of international cooperation in education. Guidelines to promote cooperation are provided. The dominant focus and new role of universities has become problem-solving and community development, as distinct from the previous institutional-building…

  18. Diversity in human behavioral ecology.

    PubMed

    Hames, Raymond

    2014-12-01

    As befitting an evolutionary approach to the study of human behavior, the papers in this special issue of Human Nature cover a diversity of topics in modern and traditional societies. They include the goals of hunting in foraging societies, social bias, cooperative breeding, the impact of war on women, leadership, and social mobility. In combination these contributions demonstrate the utility of selectionist's thinking on a wide variety of topics. While many of the contributions employ standard evolutionary biological approaches such as kin selection, cooperative breeding and the Trivers-Willard model, others examine important human issues such as the problems of trust, the cost of war to women, the characteristics of leaders, and what might be called honest or rule-bound fights. One striking feature of many of the contributions is a novel reexamination of traditional research questions from an evolutionary perspective.

  19. Cognitive diversity and moral enhancement.

    PubMed

    Gyngell, Chris; Easteal, Simon

    2015-01-01

    One debate in contemporary bioethics centers on whether the development of cognitive enhancement technologies (CETs) will hasten the need for moral enhancement. In this article we provide a new argument in favor of pursuing these enhancement technologies together. The widespread availability of CETs will likely increase population-level cognitive diversity. Different people will choose to enhance different aspects of their cognition, and some won't enhance themselves at all. Although this has the potential to be beneficial for society, it could also result in harms as people become more different from one another. Aspects of our moral psychology make it difficult for people to cooperate and coordinate actions with those who are very different from themselves. These moral failings could be targeted by moral enhancement technologies, which may improve cooperation among individuals. Moral enhancement technologies will therefore help society maximize the benefits, and reduce the costs, associated with widespread access to cognitive enhancements.

  20. Diversity in human behavioral ecology.

    PubMed

    Hames, Raymond

    2014-12-01

    As befitting an evolutionary approach to the study of human behavior, the papers in this special issue of Human Nature cover a diversity of topics in modern and traditional societies. They include the goals of hunting in foraging societies, social bias, cooperative breeding, the impact of war on women, leadership, and social mobility. In combination these contributions demonstrate the utility of selectionist's thinking on a wide variety of topics. While many of the contributions employ standard evolutionary biological approaches such as kin selection, cooperative breeding and the Trivers-Willard model, others examine important human issues such as the problems of trust, the cost of war to women, the characteristics of leaders, and what might be called honest or rule-bound fights. One striking feature of many of the contributions is a novel reexamination of traditional research questions from an evolutionary perspective. PMID:25277060

  1. Cooperative transport in nanochannels.

    PubMed

    Bauer, Wolfgang R; Nadler, Walter

    2013-07-01

    Channel transport of different species of particles is viewed usually only in terms of competition and selectivity. In this paper we show that transport of one species may be promoted by the presence of another and that both may even mutually cooperate. We investigate a discretized Markovian model of nanochannel transport via in-channel sites, allowing for the simultaneous transport of several different species of particles; interaction between transported particles is included via the condition of single occupancy on a channel site. By numerically solving the model exactly, particularly an analysis of situations of crowding in the channel is possible and we observe three situations: mutual cooperation, promotion of one species at the cost of the other, and mutual competition. The physical situation has a strong nonequilibrium character as Onsager's relations on coupled flows do not hold.

  2. Cooperative photoredox catalysis.

    PubMed

    Lang, Xianjun; Zhao, Jincai; Chen, Xiaodong

    2016-05-31

    Visible-light photoredox catalysis has been experiencing a renaissance in response to topical interest in renewable energy and green chemistry. The latest progress in this area indicates that cooperation between photoredox catalysis and other domains of catalysis could provide effective results. Thus, we advance the concept of cooperative photoredox catalysis for organic transformations. It is important to note that this concept can bridge the gap between visible-light photoredox catalysis and other types of redox catalysis such as transition-metal catalysis, biocatalysis or electrocatalysis. In doing so, one can take advantage of the best of both worlds in establishing organic synthesis with visible-light-induced redox reaction as a crucial step. PMID:27094803

  3. Squaring cooperative binding circles

    PubMed Central

    Deutman, Alexander B. C.; Monnereau, Cyrille; Moalin, Mohamed; Coumans, Ruud G. E.; Veling, Nico; Coenen, Michiel; Smits, Jan M. M.; de Gelder, René; Elemans, Johannes A. A. W.; Ercolani, Gianfranco; Nolte, Roeland J. M.; Rowan, Alan E.

    2009-01-01

    The cooperative binding effects of viologens and pyridines to a synthetic bivalent porphyrin receptor are used as a model system to study how the magnitudes of these effects relate to the experimentally obtained values. The full thermodynamic and kinetic circles concerning both activation and inhibition of the cage of the receptor for the binding of viologens were measured and evaluated. The results strongly emphasize the apparent character of measured binding and rate constants, in which the fractional saturation of receptors with other guests is linearly expressed in these constants. The presented method can be used as a simple tool to better analyze and comprehend the experimentally observed kinetics and thermodynamics of natural and artificial cooperative systems. PMID:19470643

  4. Cooperation in space

    NASA Technical Reports Server (NTRS)

    Guastaferro, A.

    1992-01-01

    The topics from the Technical Interchange Meeting for the NASA Space Exploration Initiative are presented in viewgraph form. The objective is to share a perspective of a cost-effective cooperation management structure of NASA and industry as we move towards the 21st century and the national commitment to continue our exploration in space with humans. Some of the topics covered include a personal background, today's culture, new approaches, congressional oversight, programmatic impact, and recommendations.

  5. Automated Cooperative Trajectories

    NASA Technical Reports Server (NTRS)

    Hanson, Curt; Pahle, Joseph; Brown, Nelson

    2015-01-01

    This presentation is an overview of the Automated Cooperative Trajectories project. An introduction to the phenomena of wake vortices is given, along with a summary of past research into the possibility of extracting energy from the wake by flying close parallel trajectories. Challenges and barriers to adoption of civilian automatic wake surfing technology are identified. A hardware-in-the-loop simulation is described that will support future research. Finally, a roadmap for future research and technology transition is proposed.

  6. Cooperativity in Tetrel Bonds.

    PubMed

    Marín-Luna, Marta; Alkorta, Ibon; Elguero, José

    2016-02-01

    A theoretical study of the cooperativity in linear chains of (H3SiCN)n and (H3SiNC)n complexes connected by tetrel bonds has been carried out by means of MP2 and CCSD(T) computational methods. In all cases, a favorable cooperativity is observed, especially in some of the largest linear chains of (H3SiNC)n, where the effect is so large that the SiH3 group is almost equidistant to the two surrounding CN groups and it becomes planar. In addition, the combination of tetrel bonds with other weak interactions (halogen, chalcogen, pnicogen, triel, beryllium, lithium, and hydrogen bond) has been explored using ternary complexes, (H3SiCN)2:XY and (H3SiNC)2:XY. In all cases, positive cooperativity is obtained, especially in the (H3SiNC)2:ClF and (H3SiNC)2:SHF ternary complexes, where, respectively, halogen and chalcogen shared complexes are formed. PMID:26756083

  7. Hydrodynamics of Bacterial Cooperation

    NASA Astrophysics Data System (ADS)

    Petroff, A.; Libchaber, A.

    2012-12-01

    Over the course of the last several decades, the study of microbial communities has identified countless examples of cooperation between microorganisms. Generally—as in the case of quorum sensing—cooperation is coordinated by a chemical signal that diffuses through the community. Less well understood is a second class of cooperation that is mediated through physical interactions between individuals. To better understand how the bacteria use hydrodynamics to manipulate their environment and coordinate their actions, we study the sulfur-oxidizing bacterium Thiovulum majus. These bacteria live in the diffusive boundary layer just above the muddy bottoms of ponds. As buried organic material decays, sulfide diffuses out of the mud. Oxygen from the pond diffuses into the boundary layer from above. These bacteria form communities—called veils— which are able to transport nutrients through the boundary layer faster than diffusion, thereby increasing their metabolic rate. In these communities, bacteria attach to surfaces and swim in place. As millions of bacteria beat their flagella, the community induces a macroscopic fluid flow, which mix the boundary layer. Here we present experimental observations and mathematical models that elucidate the hydrodynamics linking the behavior of an individual bacterium to the collective dynamics of the community. We begin by characterizing the flow of water around an individual bacterium swimming in place. We then discuss the flow of water and nutrients around a small number of individuals. Finally, we present observations and models detailing the macroscopic dynamics of a Thiovulum veil.

  8. 75 FR 10319 - Cooper Tools-Sumter, Cooper Tools Divisions, a Subsidiary of Cooper Industries, Inc., Including...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-05

    ... published in the Federal Register on September 21, 2006 (71 FR 55216). In order to avoid an overlap in... Employment and Training Administration Cooper Tools--Sumter, Cooper Tools Divisions, a Subsidiary of Cooper... workers of Cooper Tools--Sumter, Cooper Tools Division, a subsidiary of Cooper Industries, Inc.,...

  9. Valuing Diversity

    PubMed Central

    Fryer, Roland G.; Loury, Glenn C.

    2014-01-01

    This paper explores the economics of diversity-enhancing policies. A model is proposed in which heterogeneous agents, distinguished by skill level and social identity, purchase productive opportunities in a competitive market. We analyze policies designed to raise the status of a disadvantaged identity group. When agent identity is contractible, efficient policy grants preferred access to slots but offers no direct assistance for acquiring skills. When identity is not contractible, efficient policy provides universal subsidies to skill development when the fraction of the disadvantaged group at the skill development margin is larger than their share at the slot assignment margin. PMID:25525280

  10. Evolution of cooperation among tumor cells.

    PubMed

    Axelrod, Robert; Axelrod, David E; Pienta, Kenneth J

    2006-09-01

    The evolution of cooperation has a well established theoretical framework based on game theory. This approach has made valuable contributions to a wide variety of disciplines, including political science, economics, and evolutionary biology. Existing cancer theory suggests that individual clones of cancer cells evolve independently from one another, acquiring all of the genetic traits or hallmarks necessary to form a malignant tumor. It is also now recognized that tumors are heterotypic, with cancer cells interacting with normal stromal cells within the tissue microenvironment, including endothelial, stromal, and nerve cells. This tumor cell-stromal cell interaction in itself is a form of commensalism, because it has been demonstrated that these nonmalignant cells support and even enable tumor growth. Here, we add to this theory by regarding tumor cells as game players whose interactions help to determine their Darwinian fitness. We marshal evidence that tumor cells overcome certain host defenses by means of diffusible products. Our original contribution is to raise the possibility that two nearby cells can protect each other from a set of host defenses that neither could survive alone. Cooperation can evolve as by-product mutualism among genetically diverse tumor cells. Our hypothesis supplements, but does not supplant, the traditional view of carcinogenesis in which one clonal population of cells develops all of the necessary genetic traits independently to form a tumor. Cooperation through the sharing of diffusible products raises new questions about tumorigenesis and has implications for understanding observed phenomena, designing new experiments, and developing new therapeutic approaches.

  11. How is human cooperation different?

    PubMed Central

    Melis, Alicia P.; Semmann, Dirk

    2010-01-01

    Although cooperation is a widespread phenomenon in nature, human cooperation exceeds that of all other species with regard to the scale and range of cooperative activities. Here we review and discuss differences between humans and non-humans in the strategies employed to maintain cooperation and control free-riders. We distinguish forms of cooperative behaviour based on their influence on the immediate payoffs of actor and recipient. If the actor has immediate costs and only the recipient obtains immediate benefits, we term this investment. If the behaviour has immediate positive effects for both actor and recipient, we call this a self-serving mutually beneficial behaviour or mutual cooperation. We argue that humans, in contrast to all other species, employ a wider range of enforcement mechanisms, which allow higher levels of cooperation to evolve and stabilize among unrelated individuals and in large groups. We also discuss proximate mechanisms underlying cooperative behaviour and focus on our experimental work with humans and our closest primate relatives. Differences in the proximate mechanisms also seem to contribute to explaining humans' greater ability to cooperate and enforce cooperation. PMID:20679110

  12. Cooperativity in beryllium bonds.

    PubMed

    Alkorta, Ibon; Elguero, José; Yáñez, Manuel; Mó, Otilia

    2014-03-01

    A theoretical study of the beryllium bonded clusters of the (iminomethyl)beryllium hydride and (iminomethyl)beryllium fluoride [HC(BeX)=NH, X = H, F] molecules has been carried out at the B3LYP/6-311++G(3df,2p) level of theory. Linear and cyclic clusters have been characterized up to the decamer. The geometric, energetic, electronic and NMR properties of the clusters clearly indicate positive cooperativity. The evolution of the molecular properties, as the size of the cluster increases, is similar to those reported in polymers held together by hydrogen bonds.

  13. CLEW: A Cooperative Learning Environment for the Web.

    ERIC Educational Resources Information Center

    Ribeiro, Marcelo Blois; Noya, Ricardo Choren; Fuks, Hugo

    This paper outlines CLEW (collaborative learning environment for the Web). The project combines MUD (Multi-User Dimension), workflow, VRML (Virtual Reality Modeling Language) and educational concepts like constructivism in a learning environment where students actively participate in the learning process. The MUD shapes the environment structure.…

  14. Adaptation to a new environment allows cooperators to purge cheaters stochastically.

    PubMed

    Waite, Adam James; Shou, Wenying

    2012-11-20

    Cooperation via production of common goods is found in diverse life forms ranging from viruses to social animals. However, natural selection predicts a "tragedy of the commons": Cheaters, benefiting from without producing costly common goods, are more fit than cooperators and should destroy cooperation. In an attempt to discover novel mechanisms of cheater control, we eliminated known ones using a yeast cooperator-cheater system engineered to supply or exploit essential nutrients. Surprisingly, although less fit than cheaters, cooperators quickly dominated a fraction of cocultures. Cooperators isolated from these cocultures were superior to the cheater isolates they had been cocultured with, even though these cheaters were superior to ancestral cooperators. Resequencing and phenotypic analyses revealed that evolved cooperators and cheaters all harbored mutations adaptive to the nutrient-limited cooperative environment, allowing growth at a much lower concentration of nutrient than their ancestors. Even after the initial round of adaptation, evolved cooperators still stochastically dominated cheaters derived from them. We propose the "adaptive race" model: If during adaptation to an environment, the fitness gain of cooperators exceeds that of cheaters by at least the fitness cost of cooperation, the tragedy of the commons can be averted. Although cooperators and cheaters sample from the same pool of adaptive mutations, this symmetry is soon broken: The best cooperators purge cheaters and continue to grow, whereas the best cheaters cause rapid self-extinction. We speculate that adaptation to changing environments may contribute to the persistence of cooperative systems before the appearance of more sophisticated mechanisms of cheater control. PMID:23091010

  15. Cooperation, conformity, and the coevolutionary problem of trait associations.

    PubMed

    Van Cleve, Jeremy

    2016-05-01

    In large scale social systems, coordinated or cooperative outcomes become difficult because encounters between kin or repeated encounters between friends are infrequent. Even punishment of noncooperators does not entirely alleviate the dilemma. One important mechanism for achieving cooperative outcomes in such social systems is conformist bias where individuals copy the behavior performed by the majority of their group mates. Conformist bias enhances group competition by both stabilizing behaviors within groups and increasing variance between groups. Due to this group competition effect, conformist bias is thought to have been an important driver of human social complexity and cultural diversity. However, conformist bias only evolves indirectly through associations with other traits, and I show that such associations are more difficult to obtain than previously expected. Specifically, I show that initial measures of population structure must be strong in order for a strong association between conformist bias and cooperative behaviors (cooperation and costly punishment) to evolve and for these traits to reach high frequencies. Additionally, the required initial level of association does not evolve de novo in simulations run over long timescales. This suggests that the coevolution of cooperative behaviors and conformist bias alone may not explain the high levels of cooperation within human groups, though conformist bias may still play an important role in combination with other social and demographic forces. PMID:26907203

  16. The evolution of cooperation within the gut microbiota.

    PubMed

    Rakoff-Nahoum, Seth; Foster, Kevin R; Comstock, Laurie E

    2016-04-25

    Cooperative phenotypes are considered central to the functioning of microbial communities in many contexts, including communication via quorum sensing, biofilm formation, antibiotic resistance, and pathogenesis. The human intestine houses a dense and diverse microbial community critical to health, yet we know little about cooperation within this important ecosystem. Here we test experimentally for evolved cooperation within the Bacteroidales, the dominant Gram-negative bacteria of the human intestine. We show that during growth on certain dietary polysaccharides, the model member Bacteroides thetaiotaomicron exhibits only limited cooperation. Although this organism digests these polysaccharides extracellularly, mutants lacking this ability are outcompeted. In contrast, we discovered a dedicated cross-feeding enzyme system in the prominent gut symbiont Bacteroides ovatus, which digests polysaccharide at a cost to itself but at a benefit to another species. Using in vitro systems and gnotobiotic mouse colonization models, we find that extracellular digestion of inulin increases the fitness of B. ovatus owing to reciprocal benefits when it feeds other gut species such as Bacteroides vulgatus. This is a rare example of naturally-evolved cooperation between microbial species. Our study reveals both the complexity and importance of cooperative phenotypes within the mammalian intestinal microbiota.

  17. The evolution of cooperation within the gut microbiota

    PubMed Central

    Rakoff-Nahoum, Seth; Foster, Kevin R.; Comstock, Laurie E.

    2016-01-01

    Cooperative phenotypes are considered central to the functioning of microbial communities in many contexts, including communication via quorum sensing, biofilm formation, antibiotic resistance, and pathogenesis1-5. The human intestine houses a dense and diverse microbial community critical to health1,2,4-9, yet we know little about cooperation within this important ecosystem. Here we experimentally test for evolved cooperation within the Bacteroidales, the dominant Gram-negative bacteria of the human intestine. We show that during growth on certain dietary polysaccharides, the model member Bacteroides thetaiotaomicron exhibits only limited cooperation. Although this organism digests these polysaccharides extracellularly, mutants lacking this ability are outcompeted. In contrast, we discovered a dedicated cross-feeding enzyme system in the prominent gut symbiont Bacteroides ovatus, which digests polysaccharide at a cost to itself but at a benefit to another species. Using in vitro systems and gnotobiotic mouse colonization models, we find that extracellular digestion of inulin increases the fitness of B.ovatus due to reciprocal benefits when it feeds other gut species such as Bacteroides vulgatus. This is a rare example of naturally-evolved cooperation between microbial species. Our study reveals both the complexity and importance of cooperative phenotypes within the mammalian intestinal microbiota. PMID:27111508

  18. Cooperation, conformity, and the coevolutionary problem of trait associations.

    PubMed

    Van Cleve, Jeremy

    2016-05-01

    In large scale social systems, coordinated or cooperative outcomes become difficult because encounters between kin or repeated encounters between friends are infrequent. Even punishment of noncooperators does not entirely alleviate the dilemma. One important mechanism for achieving cooperative outcomes in such social systems is conformist bias where individuals copy the behavior performed by the majority of their group mates. Conformist bias enhances group competition by both stabilizing behaviors within groups and increasing variance between groups. Due to this group competition effect, conformist bias is thought to have been an important driver of human social complexity and cultural diversity. However, conformist bias only evolves indirectly through associations with other traits, and I show that such associations are more difficult to obtain than previously expected. Specifically, I show that initial measures of population structure must be strong in order for a strong association between conformist bias and cooperative behaviors (cooperation and costly punishment) to evolve and for these traits to reach high frequencies. Additionally, the required initial level of association does not evolve de novo in simulations run over long timescales. This suggests that the coevolution of cooperative behaviors and conformist bias alone may not explain the high levels of cooperation within human groups, though conformist bias may still play an important role in combination with other social and demographic forces.

  19. The evolution of cooperation within the gut microbiota.

    PubMed

    Rakoff-Nahoum, Seth; Foster, Kevin R; Comstock, Laurie E

    2016-05-12

    Cooperative phenotypes are considered central to the functioning of microbial communities in many contexts, including communication via quorum sensing, biofilm formation, antibiotic resistance, and pathogenesis. The human intestine houses a dense and diverse microbial community critical to health, yet we know little about cooperation within this important ecosystem. Here we test experimentally for evolved cooperation within the Bacteroidales, the dominant Gram-negative bacteria of the human intestine. We show that during growth on certain dietary polysaccharides, the model member Bacteroides thetaiotaomicron exhibits only limited cooperation. Although this organism digests these polysaccharides extracellularly, mutants lacking this ability are outcompeted. In contrast, we discovered a dedicated cross-feeding enzyme system in the prominent gut symbiont Bacteroides ovatus, which digests polysaccharide at a cost to itself but at a benefit to another species. Using in vitro systems and gnotobiotic mouse colonization models, we find that extracellular digestion of inulin increases the fitness of B. ovatus owing to reciprocal benefits when it feeds other gut species such as Bacteroides vulgatus. This is a rare example of naturally-evolved cooperation between microbial species. Our study reveals both the complexity and importance of cooperative phenotypes within the mammalian intestinal microbiota. PMID:27111508

  20. Network Modularity is essential for evolution of cooperation under uncertainty

    PubMed Central

    Gianetto, David A.; Heydari, Babak

    2015-01-01

    Cooperative behavior, which pervades nature, can be significantly enhanced when agents interact in a structured rather than random way; however, the key structural factors that affect cooperation are not well understood. Moreover, the role structure plays with cooperation has largely been studied through observing overall cooperation rather than the underlying components that together shape cooperative behavior. In this paper we address these two problems by first applying evolutionary games to a wide range of networks, where agents play the Prisoner's Dilemma with a three-component stochastic strategy, and then analyzing agent-based simulation results using principal component analysis. With these methods we study the evolution of trust, reciprocity and forgiveness as a function of several structural parameters. This work demonstrates that community structure, represented by network modularity, among all the tested structural parameters, has the most significant impact on the emergence of cooperative behavior, with forgiveness showing the largest sensitivity to community structure. We also show that increased community structure reduces the dispersion of trust and forgiveness, thereby reducing the network-level uncertainties for these two components; graph transitivity and degree also significantly influence the evolutionary dynamics of the population and the diversity of strategies at equilibrium. PMID:25849737

  1. Network Modularity is essential for evolution of cooperation under uncertainty

    NASA Astrophysics Data System (ADS)

    Gianetto, David A.; Heydari, Babak

    2015-04-01

    Cooperative behavior, which pervades nature, can be significantly enhanced when agents interact in a structured rather than random way; however, the key structural factors that affect cooperation are not well understood. Moreover, the role structure plays with cooperation has largely been studied through observing overall cooperation rather than the underlying components that together shape cooperative behavior. In this paper we address these two problems by first applying evolutionary games to a wide range of networks, where agents play the Prisoner's Dilemma with a three-component stochastic strategy, and then analyzing agent-based simulation results using principal component analysis. With these methods we study the evolution of trust, reciprocity and forgiveness as a function of several structural parameters. This work demonstrates that community structure, represented by network modularity, among all the tested structural parameters, has the most significant impact on the emergence of cooperative behavior, with forgiveness showing the largest sensitivity to community structure. We also show that increased community structure reduces the dispersion of trust and forgiveness, thereby reducing the network-level uncertainties for these two components; graph transitivity and degree also significantly influence the evolutionary dynamics of the population and the diversity of strategies at equilibrium.

  2. Network Modularity is essential for evolution of cooperation under uncertainty.

    PubMed

    Gianetto, David A; Heydari, Babak

    2015-01-01

    Cooperative behavior, which pervades nature, can be significantly enhanced when agents interact in a structured rather than random way; however, the key structural factors that affect cooperation are not well understood. Moreover, the role structure plays with cooperation has largely been studied through observing overall cooperation rather than the underlying components that together shape cooperative behavior. In this paper we address these two problems by first applying evolutionary games to a wide range of networks, where agents play the Prisoner's Dilemma with a three-component stochastic strategy, and then analyzing agent-based simulation results using principal component analysis. With these methods we study the evolution of trust, reciprocity and forgiveness as a function of several structural parameters. This work demonstrates that community structure, represented by network modularity, among all the tested structural parameters, has the most significant impact on the emergence of cooperative behavior, with forgiveness showing the largest sensitivity to community structure. We also show that increased community structure reduces the dispersion of trust and forgiveness, thereby reducing the network-level uncertainties for these two components; graph transitivity and degree also significantly influence the evolutionary dynamics of the population and the diversity of strategies at equilibrium. PMID:25849737

  3. Mir Cooperative Solar Array

    NASA Technical Reports Server (NTRS)

    Skor, Mike; Hoffman, Dave J.

    1997-01-01

    The Mir Cooperative Solar Array (MCSA), produced jointly by the United States and Russia, was deployed on the Mir Russian space station on May 25, 1996. The MCSA is a photovoltaic electrical power system that can generate up to 6 kW. The power from the MCSA is needed to extend Mir's lifetime and to support experiments conducted there by visiting U.S. astronauts. The MCSA was brought to Mir via the Space Shuttle Atlantis on the STS-74 mission, launched November 12, 1995. This cooperative venture combined the best technology of both countries: the United States provided high-efficiency, lightweight photovoltaic panel modules, whereas Russia provided the array structure and deployment mechanism. Technology developed in the Space Station Freedom Program, and now being used in the International Space Station, was used to develop MCSA's photovoltaic panel. Performance data obtained from MCSA operation on Mir will help engineers better understand the performance of the photovoltaic panel modules in orbit. This information will be used to more accurately predict the performance of the International Space Station solar arrays. Managed by the NASA Lewis Research Center for NASA's International Space Station Program Office in Houston, Texas, the MCSA Project was completed on time and under budget despite a very aggressive schedule.

  4. Optical Circuitry Cooperative

    NASA Astrophysics Data System (ADS)

    Gibbs, H. M.; Gibson, U.; Peyghambarian, N.; Sarid, D.; Stegeman, G.

    1985-01-01

    An Optical Circuitry Cooperative (OCC) has been formed as an NSF cooperative research center in which six or more companies contribute financial support; NSF provides support which declines to zero in five years. Companies benefit from a center by early access to research results, leverage for their research dollars, participation in research selection, and improved relations with faculty and students. The university receives support for a major research program that increases its research capability, provides reasonably stable funding, and opens more opportunities for graduate students. The potential of optical circuitry has been discussed for many years, but the excitement is growing rapidly on the strength of the success of optical fibers for optical transmission, the generation of subpicosecond opitcal pulses, and the development of promising optical logic elements, such as optical bistable devices. And yet, much research remains to be done to discover the best nonlinear optical materials and fabrication techniques. OCC will perform research to provide a data base to allow the development of optical circuitry devices. The areas encompassed by OCC include all-optical logic, picosecond decision-making, guided-wave preprocessors, opti-cal interconnects within computers (both fiber and whole-array imaging), optical storage, and optical computer architecture and devices.

  5. Cooperative nonproliferation activities

    SciTech Connect

    Ystesund, K.; Furaus, J.; Lucero, R.

    1997-08-01

    Sandia National Laboratories (SNL) under DOE sponsorship is engaged in nuclear nonproliferation activities with the Power Reactor and Nuclear Fuel Development Corporation (PNC) of Japan. From 1995 to the present SNL and PNC have been participating in a cooperative project to implement and assess the use of remote monitoring to achieve nuclear nonproliferation objectives. Implementation of remote monitoring at the PNC Joyo facility took place during 1996 and continues to date. An International Fellowship began in the Fall of 1995 and has complemented the nonproliferation study. Plans are underway to extend the Fellowship and to upgrade the existing Remote Monitoring System to include another area at the Joyo facility. SNL and PNC are currently exploring the possibility of exchanging experts with the objective of promoting regional confidence building in Northeast Asia, possibly using some of the same remote monitoring technologies. This paper will provide an overview of these activities and report on the status of cooperative nonproliferation activities being conducted by PNC and SNL.

  6. Resource heterogeneity can facilitate cooperation.

    PubMed

    Kun, Ádám; Dieckmann, Ulf

    2013-01-01

    Although social structure is known to promote cooperation, by locally exposing selfish agents to their own deeds, studies to date assumed that all agents have access to the same level of resources. This is clearly unrealistic. Here we find that cooperation can be maintained when some agents have access to more resources than others. Cooperation can then emerge even in populations in which the temptation to defect is so strong that players would act fully selfishly if their resources were distributed uniformly. Resource heterogeneity can thus be crucial for the emergence and maintenance of cooperation. We also show that resource heterogeneity can hinder cooperation once the temptation to defect is significantly lowered. In all cases, the level of cooperation can be maximized by managing resource heterogeneity.

  7. Mechanisms for similarity based cooperation

    NASA Astrophysics Data System (ADS)

    Traulsen, A.

    2008-06-01

    Cooperation based on similarity has been discussed since Richard Dawkins introduced the term “green beard” effect. In these models, individuals cooperate based on an aribtrary signal (or tag) such as the famous green beard. Here, two different models for such tag based cooperation are analysed. As neutral drift is important in both models, a finite population framework is applied. The first model, which we term “cooperative tags” considers a situation in which groups of cooperators are formed by some joint signal. Defectors adopting the signal and exploiting the group can lead to a breakdown of cooperation. In this case, conditions are derived under which the average abundance of the more cooperative strategy exceeds 50%. The second model considers a situation in which individuals start defecting towards others that are not similar to them. This situation is termed “defective tags”. It is shown that in this case, individuals using tags to cooperate exclusively with their own kind dominate over unconditional cooperators.

  8. Is cooperation viable in mobile organisms? Simple Walk Away rule favors the evolution of cooperation in groups.

    PubMed

    Aktipis, C Athena

    2011-07-01

    The evolution of cooperation through partner choice mechanisms is often thought to involve relatively complex cognitive abilities. Using agent-based simulations I model a simple partner choice rule, the 'Walk Away' rule, where individuals stay in groups that provide higher returns (by virtue of having more cooperators), and 'Walk Away' from groups providing low returns. Implementing this conditional movement rule in a public goods game leads to a number of interesting findings: 1) cooperators have a selective advantage when thresholds are high, corresponding to low tolerance for defectors, 2) high thresholds lead to high initial rates of movement and low final rates of movement (after selection), and 3) as cooperation is selected, the population undergoes a spatial transition from high migration (and a many small and ephemeral groups) to low migration (and large and stable groups). These results suggest that the very simple 'Walk Away' rule of leaving uncooperative groups can favor the evolution of cooperation, and that cooperation can evolve in populations in which individuals are able to move in response to local social conditions. A diverse array of organisms are able to leave degraded physical or social environments. The ubiquitous nature of conditional movement suggests that 'Walk Away' dynamics may play an important role in the evolution of social behavior in both cognitively complex and cognitively simple organisms.

  9. Diversified Cooperative Training. Diversified Cooperative Health Occupations. Manual of Operation.

    ERIC Educational Resources Information Center

    Ohio State Dept. of Education, Columbus. Div. of Vocational and Adult Education.

    This manual is designed to assist school personnel, employers, parents/guardians, and students in understanding the policies and procedures required to operate effective diversified cooperative training (DCT) and diversified cooperative health occupations (DCHO) programs. Chapter I describes DCT/DCHO programs, their structure, types of program…

  10. Cooperative Cataloging: LC Promotes Cooperation at Asian Materials Seminar.

    ERIC Educational Resources Information Center

    Fineberg, Gail

    1998-01-01

    Discusses the Asian Materials Cataloging Seminar that the Library of Congress sponsored to promote the benefits of cooperative cataloging. Highlights include the Program for Cooperative Cataloging (PCC); high-quality, standardized, core-level cataloging records for Asian materials; name authority and subject authority programs; and the CONSER…

  11. Cooperation Prevails When Individuals Adjust Their Social Ties

    PubMed Central

    Santos, Francisco C; Pacheco, Jorge M; Lenaerts, Tom

    2006-01-01

    Conventional evolutionary game theory predicts that natural selection favours the selfish and strong even though cooperative interactions thrive at all levels of organization in living systems. Recent investigations demonstrated that a limiting factor for the evolution of cooperative interactions is the way in which they are organized, cooperators becoming evolutionarily competitive whenever individuals are constrained to interact with few others along the edges of networks with low average connectivity. Despite this insight, the conundrum of cooperation remains since recent empirical data shows that real networks exhibit typically high average connectivity and associated single-to-broad–scale heterogeneity. Here, a computational model is constructed in which individuals are able to self-organize both their strategy and their social ties throughout evolution, based exclusively on their self-interest. We show that the entangled evolution of individual strategy and network structure constitutes a key mechanism for the sustainability of cooperation in social networks. For a given average connectivity of the population, there is a critical value for the ratio W between the time scales associated with the evolution of strategy and of structure above which cooperators wipe out defectors. Moreover, the emerging social networks exhibit an overall heterogeneity that accounts very well for the diversity of patterns recently found in acquired data on social networks. Finally, heterogeneity is found to become maximal when W reaches its critical value. These results show that simple topological dynamics reflecting the individual capacity for self-organization of social ties can produce realistic networks of high average connectivity with associated single-to-broad–scale heterogeneity. On the other hand, they show that cooperation cannot evolve as a result of “social viscosity” alone in heterogeneous networks with high average connectivity, requiring the additional

  12. Cooperation prevails when individuals adjust their social ties.

    PubMed

    Santos, Francisco C; Pacheco, Jorge M; Lenaerts, Tom

    2006-10-20

    Conventional evolutionary game theory predicts that natural selection favours the selfish and strong even though cooperative interactions thrive at all levels of organization in living systems. Recent investigations demonstrated that a limiting factor for the evolution of cooperative interactions is the way in which they are organized, cooperators becoming evolutionarily competitive whenever individuals are constrained to interact with few others along the edges of networks with low average connectivity. Despite this insight, the conundrum of cooperation remains since recent empirical data shows that real networks exhibit typically high average connectivity and associated single-to-broad-scale heterogeneity. Here, a computational model is constructed in which individuals are able to self-organize both their strategy and their social ties throughout evolution, based exclusively on their self-interest. We show that the entangled evolution of individual strategy and network structure constitutes a key mechanism for the sustainability of cooperation in social networks. For a given average connectivity of the population, there is a critical value for the ratio W between the time scales associated with the evolution of strategy and of structure above which cooperators wipe out defectors. Moreover, the emerging social networks exhibit an overall heterogeneity that accounts very well for the diversity of patterns recently found in acquired data on social networks. Finally, heterogeneity is found to become maximal when W reaches its critical value. These results show that simple topological dynamics reflecting the individual capacity for self-organization of social ties can produce realistic networks of high average connectivity with associated single-to-broad-scale heterogeneity. On the other hand, they show that cooperation cannot evolve as a result of "social viscosity" alone in heterogeneous networks with high average connectivity, requiring the additional mechanism of

  13. Cooperative phenomena in swarms

    SciTech Connect

    Millonas, M.M.

    1992-12-01

    A model of the cooperative behavior of a large number of locally acting organisms is proposed. The space in which the organisms move is discretized, and is modeled by a lattice of nodes, or cells. Each cell has a specified volume, and is connected to other cells in the space in a definite way. Organisms move probabilistically between local cells in this space, but with weights dependent on local morphogenic substances, or morphogens. The morphogens are in turn are effected by the passage of an organism. The evolution of the morphogens, and the corresponding flow of the organisms constitutes the collective behavior of the group. The generic properties of such systems are analyzed, and a number of results are obtained. The model has various types of phase transitions and self-organizing properties controlled both by the level of the noise, and other parameters.

  14. Cooperative phenomena in swarms

    SciTech Connect

    Millonas, M.M.

    1992-01-01

    A model of the cooperative behavior of a large number of locally acting organisms is proposed. The space in which the organisms move is discretized, and is modeled by a lattice of nodes, or cells. Each cell has a specified volume, and is connected to other cells in the space in a definite way. Organisms move probabilistically between local cells in this space, but with weights dependent on local morphogenic substances, or morphogens. The morphogens are in turn are effected by the passage of an organism. The evolution of the morphogens, and the corresponding flow of the organisms constitutes the collective behavior of the group. The generic properties of such systems are analyzed, and a number of results are obtained. The model has various types of phase transitions and self-organizing properties controlled both by the level of the noise, and other parameters.

  15. Cooperative runtime monitoring

    NASA Astrophysics Data System (ADS)

    Hallé, Sylvain

    2013-11-01

    Requirements on message-based interactions can be formalised as an interface contract that specifies constraints on the sequence of possible messages that can be exchanged by multiple parties. At runtime, each peer can monitor incoming messages and check that the contract is correctly being followed by their respective senders. We introduce cooperative runtime monitoring, where a recipient 'delegates' its monitoring task to the sender, which is required to provide evidence that the message it sends complies with the contract. In turn, this evidence can be quickly checked by the recipient, which is then guaranteed of the sender's compliance to the contract without doing the monitoring computation by itself. A particular application of this concept is shown on web services, where service providers can monitor and enforce contract compliance of third-party clients at a small cost on the server side, while avoiding to certify or digitally sign them.

  16. Allostery and cooperativity revisited

    PubMed Central

    Cui, Qiang; Karplus, Martin

    2008-01-01

    Although phenomenlogical models that account for cooperativity in allosteric systems date back to the early and mid-60's (e.g., the KNF and MWC models), there is resurgent interest in the topic due to the recent experimental and computational studies that attempted to reveal, at an atomistic level, how allostery actually works. In this review, using systems for which atomistic simulations have been carried out in our groups as examples, we describe the current understanding of allostery, how the mechanisms go beyond the classical MWC/Pauling-KNF descriptions, and point out that the “new view” of allostery, emphasizing “population shifts,” is, in fact, an “old view.” The presentation offers not only an up-to-date description of allostery from a theoretical/computational perspective, but also helps to resolve several outstanding issues concerning allostery. PMID:18560010

  17. Diverse Classrooms, Diverse Curriculum, Diverse Complications: Three Teacher Perspectives

    ERIC Educational Resources Information Center

    Ungemah, Lori D.

    2015-01-01

    Racial, ethnic, linguistic, and religious diversity continues to increase in classrooms. Many call for a more diverse curriculum, but curricular diversity brings its own challenges to both teachers and students. These three vignettes are drawn from my ethnographic data at Atlantic High School in Brooklyn, New York, where I worked for ten years as…

  18. Cooperation and Coordination Between Fuzzy Reinforcement Learning Agents in Continuous State Partially Observable Markov Decision Processes

    NASA Technical Reports Server (NTRS)

    Berenji, Hamid R.; Vengerov, David

    1999-01-01

    Successful operations of future multi-agent intelligent systems require efficient cooperation schemes between agents sharing learning experiences. We consider a pseudo-realistic world in which one or more opportunities appear and disappear in random locations. Agents use fuzzy reinforcement learning to learn which opportunities are most worthy of pursuing based on their promise rewards, expected lifetimes, path lengths and expected path costs. We show that this world is partially observable because the history of an agent influences the distribution of its future states. We consider a cooperation mechanism in which agents share experience by using and-updating one joint behavior policy. We also implement a coordination mechanism for allocating opportunities to different agents in the same world. Our results demonstrate that K cooperative agents each learning in a separate world over N time steps outperform K independent agents each learning in a separate world over K*N time steps, with this result becoming more pronounced as the degree of partial observability in the environment increases. We also show that cooperation between agents learning in the same world decreases performance with respect to independent agents. Since cooperation reduces diversity between agents, we conclude that diversity is a key parameter in the trade off between maximizing utility from cooperation when diversity is low and maximizing utility from competitive coordination when diversity is high.

  19. Adaptation to a new environment allows cooperators to purge cheaters stochastically

    PubMed Central

    Waite, Adam James; Shou, Wenying

    2012-01-01

    Cooperation via production of common goods is found in diverse life forms ranging from viruses to social animals. However, natural selection predicts a “tragedy of the commons”: Cheaters, benefiting from without producing costly common goods, are more fit than cooperators and should destroy cooperation. In an attempt to discover novel mechanisms of cheater control, we eliminated known ones using a yeast cooperator–cheater system engineered to supply or exploit essential nutrients. Surprisingly, although less fit than cheaters, cooperators quickly dominated a fraction of cocultures. Cooperators isolated from these cocultures were superior to the cheater isolates they had been cocultured with, even though these cheaters were superior to ancestral cooperators. Resequencing and phenotypic analyses revealed that evolved cooperators and cheaters all harbored mutations adaptive to the nutrient-limited cooperative environment, allowing growth at a much lower concentration of nutrient than their ancestors. Even after the initial round of adaptation, evolved cooperators still stochastically dominated cheaters derived from them. We propose the “adaptive race” model: If during adaptation to an environment, the fitness gain of cooperators exceeds that of cheaters by at least the fitness cost of cooperation, the tragedy of the commons can be averted. Although cooperators and cheaters sample from the same pool of adaptive mutations, this symmetry is soon broken: The best cooperators purge cheaters and continue to grow, whereas the best cheaters cause rapid self-extinction. We speculate that adaptation to changing environments may contribute to the persistence of cooperative systems before the appearance of more sophisticated mechanisms of cheater control. PMID:23091010

  20. Enhancement of cooperation in prisoner’s dilemma game on weighted lattices

    NASA Astrophysics Data System (ADS)

    Xia, Cheng-yi; Ma, Zhi-qin; Wang, Yi-ling; Wang, Jin-song; Chen, Zeng-qiang

    2011-11-01

    We introduce the vertex weight into the spatial prisoners’ dilemma game to investigate the evolution of cooperation. Each player on a square lattice is assigned to a particular weight followed by three types of distributions, which include the exponential, power-law and uniform ones. Compared with the traditional version, we find that the cooperation level is markedly enhanced under the weighted square lattice. For most ranges of b, the highest cooperation level can be obtained under the uniform distribution, while power-law distribution usually leads to the lowest cooperation. The distributed weight can produce a heavy heterogeneity among the individuals’ payoff, some cooperators with higher weight will foster the cooperative clusters and even spread the cooperation strategy around the clusters, while defectors have no such advantages. In addition, we still investigate the impact of the amplitude of undulation of weight distribution on the cooperation, and the non-monotonic behavior about b is observed. Finally, the influence of noise on the cooperation is also studied for these types of distribution of weight. To some extent, our weighted scheme can characterize the difference or diversity of players, which will be beneficial to further understand the role of individuals during the evolution of cooperation.

  1. Biliopancreatic diversion.

    PubMed

    Scopinaro, N; Adami, G F; Marinari, G M; Gianetta, E; Traverso, E; Friedman, D; Camerini, G; Baschieri, G; Simonelli, A

    1998-09-01

    Biliopancreatic diversion (BPD) has made reacceptable the malabsorptive approach to the surgical treatment of obesity. The procedure, in a series of 2241 patients operated on during a 21-year period, caused a mean permanent reduction of about 75% of the initial excess weight. The indefinite weight maintenance appears to be due to the existence of a threshold absorption capacity for fat and starch, and thus energy, and the weight loss is partly due to increased resting energy expenditure. Beneficial effects other than those consequent to weight loss or reduced nutrient absorption included permanent normalization of serum glucose and cholesterol without any medication and on totally free diet in 100% of cases, both phenomena being due to a specific action of the operation. Operative mortality was less than 0.5%. Specific late complications included anemia, less than 5% with adequate iron or folate supplementation (or both); stomal ulcer, reduced to 3.2% by oral H2-blocker prophylaxis; bone demineralization, increasing up to the fourth year and tending to decrease thereafter, with need of calcium and vitamin D supplementation; neurologic complications, totally avoidable by prompt vitamin B administration to patients at risk; protein malnutrition, which was reduced to a minimum of 3% with 1.3% recurrence, in exchange with a smaller weight loss, by adapting the volume of the gastric remnant and the length of the alimentary limb to the patient's individual characteristics. It is concluded that the correct use of BPD, based on the knowledge of its mechanisms of action, can make the procedure an effective, safe one in all hands.

  2. Cooperative Education in Outdoor Education

    ERIC Educational Resources Information Center

    Martin, Andy; Flemming, Jenny

    2010-01-01

    Cooperative education is a structured experiential education strategy integrating classroom studies with work place learning. The purpose of this paper is to evaluate how a cooperative education model can be included within an outdoor education undergraduate degree to develop reflective practitioners and to enhance graduate capabilities. Document…

  3. Cooperative Learning in Elementary Schools.

    ERIC Educational Resources Information Center

    Hadderman, Margaret

    1992-01-01

    Cooperative learning is being recommended as a solution for numerous education problems, from enhancing disadvantaged children's self-esteem to ensuring academic success for all students. Cooperative learning has great potential as a supplement or alternative to traditional teaching methods when students are adequately socialized and motivated.…

  4. Cooperative Learning for Remedial Students.

    ERIC Educational Resources Information Center

    Stiers, Darlene

    1989-01-01

    Offers cooperative learning instructional techniques for teaching the historical novel "The Root Cellar" in a remedial reading classroom. Recommends cooperative learning as a means through which the student can succeed academically while developing interpersonal skills. Suggests that the lesson can be adapted to match the ability level of…

  5. International Cooperation in Distance Education.

    ERIC Educational Resources Information Center

    John, Magnus

    This paper addresses some of the general issues of international cooperation within the context of distance education. Examples of the types of international cooperation are introduced in order to explain some of the pitfalls that can occur when coordinating organizations on an international level. Extensive discussion is undertaken concerning…

  6. Cooperative Learning in Communication Courses.

    ERIC Educational Resources Information Center

    Lynch, Patricia L.; And Others

    This paper presents 14 cooperative learning lesson plans and related handouts suitable for use in communication courses. The paper begins with 8 handouts that deal with objectives; criteria; differences between the old paradigm and the new paradigm based on cooperative learning; positive interdependences; group differences between cooperative…

  7. Cooperative Education for the Future.

    ERIC Educational Resources Information Center

    Hall, James W.

    1999-01-01

    Cooperative education must move into a new era of radically different, technology-driven environments in which work and study are blurred. Characteristics of a new cooperative education include (1) simultaneous study and work; (2) co-op integrated into courses; (3) faculty as consultants on co-op opportunities; (4) change in financial remuneration…

  8. Peter Cooper, the Workingman's Advocate.

    ERIC Educational Resources Information Center

    Alemanne, Nicholas

    1985-01-01

    During the 19th century, America was transformed from an agrarian to an urban-industrial society. America became divided into a nation of rich and poor. Peter Cooper assumed the role of a reformer and became the spokesman for the poor. Cooper's reform efforts and his views on unions are discussed. (RM)

  9. Cooperative processes in image segmentation

    NASA Technical Reports Server (NTRS)

    Davis, L. S.

    1982-01-01

    Research into the role of cooperative, or relaxation, processes in image segmentation is surveyed. Cooperative processes can be employed at several levels of the segmentation process as a preprocessing enhancement step, during supervised or unsupervised pixel classification and, finally, for the interpretation of image segments based on segment properties and relations.

  10. Cooperative answers in database systems

    NASA Technical Reports Server (NTRS)

    Gaasterland, Terry; Godfrey, Parke; Minker, Jack; Novik, Lev

    1993-01-01

    A major concern of researchers who seek to improve human-computer communication involves how to move beyond literal interpretations of queries to a level of responsiveness that takes the user's misconceptions, expectations, desires, and interests into consideration. At Maryland, we are investigating how to better meet a user's needs within the framework of the cooperative answering system of Gal and Minker. We have been exploring how to use semantic information about the database to formulate coherent and informative answers. The work has two main thrusts: (1) the construction of a logic formula which embodies the content of a cooperative answer; and (2) the presentation of the logic formula to the user in a natural language form. The information that is available in a deductive database system for building cooperative answers includes integrity constraints, user constraints, the search tree for answers to the query, and false presuppositions that are present in the query. The basic cooperative answering theory of Gal and Minker forms the foundation of a cooperative answering system that integrates the new construction and presentation methods. This paper provides an overview of the cooperative answering strategies used in the CARMIN cooperative answering system, an ongoing research effort at Maryland. Section 2 gives some useful background definitions. Section 3 describes techniques for collecting cooperative logical formulae. Section 4 discusses which natural language generation techniques are useful for presenting the logic formula in natural language text. Section 5 presents a diagram of the system.

  11. Cooperative Education. Instructor Coordinator's Manual.

    ERIC Educational Resources Information Center

    Farrow, Shirley

    Designed to provide an introduction to North Lake College's (NLC's) Cooperative Education Program, this manual contains information for the instructor/coordinator regarding the Dallas County Community College District's co-op policies and NLC's operational procedures and forms. First, section 1 defines cooperative education, states NLC's…

  12. Automotive Technician Educational Cooperative Program.

    ERIC Educational Resources Information Center

    Verbeck, Bill

    1998-01-01

    The Automotive Technician Educational Cooperative (ATEC), the premier applied-technology program at Truckee Meadows Community College (Sparks, Nevada), exemplifies what can be accomplished through leadership, cooperation, and dedication of a qualified faculty committed to designing and implementing a program based on standards. (JOW)

  13. Generation Z, Meet Cooperative Learning

    ERIC Educational Resources Information Center

    Igel, Charles; Urquhart, Vicki

    2012-01-01

    Today's Generation Z teens need to develop teamwork and social learning skills to be successful in the 21st century workplace. Teachers can help students develop these skills and enhance academic achievement by implementing cooperative learning strategies. Three key principles for successful cooperative learning are discussed. (Contains 1 figure.)

  14. Cooperative Learning and Teacher Education.

    ERIC Educational Resources Information Center

    Veenman, Simon; van Benthum, Niek; Bootsma, Dolly; van Dieren, Jildau; van der Kemp, Nicole

    2002-01-01

    Examined the implementation effects of a course on cooperative learning for Dutch student teachers. Data from surveys, pre- and post-course observations, and comparison of treatment of control groups indicated the course was effective in teaching participants to implement cooperative learning. The course positively affected the engagement rates of…

  15. Cooperation in Diffusive Spatial Games

    NASA Astrophysics Data System (ADS)

    Vainstein, Mendeli H.; Silva, Ana T. C.; Arenzon, Jeferson J.

    2007-05-01

    Random diffusion is shown to be an important mechanism on fostering cooperative behavior among simple agents (memoryless, unconditional cooperators or defectors) living on a spatially structured environment. In particular, under the Prisoner's Dilemma framework, when allowing the agents to move with the simple "always-move" rule, we find that cooperative behavior is not only possible but may even be enhanced. In addition, for a broad range of densities, mobile cooperators can more easily invade a population of mobile defectors, when compared with the fully viscous, immobile case. Thus, such simple mobility pattern may have played a fundamental role both in the onset and development of cooperative behavior, paving the way to more complex, individual and group, motility rules.

  16. Communications processor speeds Unix-based multi-user system

    SciTech Connect

    Pickard, M.

    1983-03-01

    Handling the many interrupts and disk accesses involved in a multiuser, multitasking environment presents a problem for Unix-based systems. The Plexus computers Inc.'s P/40 takes a multiprocessor approach, distributing tasks such as controlling high- and low-speed to outboard processors. By giving these processors their own memory and a direct-memory-access channel, they can handle most interrupts. The key component to this approach is the intelligent peripheral processor, which, along with intelligent peripheral controllers and a memory-control unit, frees the main processor to manage heavy computing loads.

  17. Quantum cryptography on multi-user network architectures

    NASA Astrophysics Data System (ADS)

    Kumavor, Patrick D.; Beal, Alan C.; Yelin, Susanne; Donkor, Eric; Wang, Bing C.

    2006-05-01

    Quantum cryptography applies the uncertainty principle and the no-cloning theorem to allow to parties to share a secret key over an ultra-secure link. Present quantum cryptography technologies provide encryption key distribution only between two users. However, practical implementations of encryption key distribution schemes require establishing secure quantum communications amongst multiple users. This paper looks at some of the advantages and drawbacks of some common network topologies that could be used in sending cryptographic keys across a network consisting of multiple users. These topologies are the star, ring, and bus networks. Their performances are compared and analyzed using quantum bit error rate analysis. The paper also presents an experimental demonstration of a six-user quantum key distribution network implemented on a bus topology.

  18. A Multi-User Remote Academic Laboratory System

    ERIC Educational Resources Information Center

    Barrios, Arquimedes; Panche, Stifen; Duque, Mauricio; Grisales, Victor H.; Prieto, Flavio; Villa, Jose L.; Chevrel, Philippe; Canu, Michael

    2013-01-01

    This article describes the development, implementation and preliminary operation assessment of Multiuser Network Architecture to integrate a number of Remote Academic Laboratories for educational purposes on automatic control. Through the Internet, real processes or physical experiments conducted at the control engineering laboratories of four…

  19. Adaptive strategy for multi-user robotic rehabilitation games.

    PubMed

    Caurin, Glauco A P; Siqueira, Adriano A G; Andrade, Kleber O; Joaquim, Ricardo C; Krebs, Hermano I

    2011-01-01

    In this paper, we discuss a strategy for the adaptation of the "difficulty level" in games intended to include motor planning during robotic rehabilitation. We consider concurrently the motivation of the user and his/her performance in a Pong game. User motivation is classified in three levels (not motivated, well motivated and overloaded). User performance is measured as a combination of knowledge of results--achieved goals and score points in the game--and knowledge of performance--joint displacement, speed, aiming, user work, etc. Initial results of a pilot test with unimpaired healthy young volunteers are also presented showing a tendency for individualization of the parameter values.

  20. Multi-User Virtual Environments Fostering Collaboration in Formal Education

    ERIC Educational Resources Information Center

    Di Blas, Nicoletta; Paolini, Paolo

    2014-01-01

    This paper is about how serious games based on MUVEs in formal education can foster collaboration. More specifically, it is about a large case-study with four different programs which took place from 2002 to 2009 and involved more than 9,000 students, aged between 12 and 18, from various nations (18 European countries, Israel and the USA). These…

  1. MOOsburg: Multi-User Domain Support for a Community Network.

    ERIC Educational Resources Information Center

    Carroll, John M.; Rosson, Mary Beth; Isenhour, Philip L.; Van Metre, Christina; Schafer, Wendy A.; Ganoe, Craig H.

    2001-01-01

    Explains MOOsburg, a community-oriented MOO that models the geography of the town of Blacksburg, Virginia and is designed to be used by local residents. Highlights include the software architecture; client-server communication; spatial database; user interface; interaction; map-based navigation; application development; and future plans. (LRW)

  2. Mobile Applications and Multi-User Virtual Reality Simulations

    NASA Technical Reports Server (NTRS)

    Gordillo, Orlando Enrique

    2016-01-01

    This is my third internship with NASA and my second one at the Johnson Space Center. I work within the engineering directorate in ER7 (Software Robotics and Simulations Division) at a graphics lab called IGOAL. We are a very well-rounded lab because we have dedicated software developers and dedicated 3D artist, and when you combine the two, what you get is the ability to create many different things such as interactive simulations, 3D models, animations, and mobile applications.

  3. Adaptive strategy for multi-user robotic rehabilitation games.

    PubMed

    Caurin, Glauco A P; Siqueira, Adriano A G; Andrade, Kleber O; Joaquim, Ricardo C; Krebs, Hermano I

    2011-01-01

    In this paper, we discuss a strategy for the adaptation of the "difficulty level" in games intended to include motor planning during robotic rehabilitation. We consider concurrently the motivation of the user and his/her performance in a Pong game. User motivation is classified in three levels (not motivated, well motivated and overloaded). User performance is measured as a combination of knowledge of results--achieved goals and score points in the game--and knowledge of performance--joint displacement, speed, aiming, user work, etc. Initial results of a pilot test with unimpaired healthy young volunteers are also presented showing a tendency for individualization of the parameter values. PMID:22254578

  4. Automatic Bluetooth testing for mobile multi-user applications

    NASA Astrophysics Data System (ADS)

    Luck, Dennis; Hörning, Henrik; Edlich, Stefan

    2008-02-01

    In this paper we present a simple approach for the development of multiuser and multimedia applications based on Bluetooth. One main obstacle for Bluetooth synchronization of mobile applications is the lack of a complete specification implementation. Nowadays these applications must be on market as fast as possible. Hence, developers must be able to test several dozens of mobile devices for their Bluetooth capability. And surprisingly, the capabilities differ not only between the Bluetooth specification 1.0 and 2.0. The current development was triggered by the development of mass applications as mobile multiuser games (e.g. Tetris). Our Application can be distributed on several mobile phones. If started, the Bluetooth applications try to connect each other and automatically start to detect device capabilities. These capabilities will be gathered and distributed to a server. The server performs statistical investigations and aggregates them to be presented as a report. The result is a faster development regarding mobile communications.

  5. Latest developments in a multi-user 3D display

    NASA Astrophysics Data System (ADS)

    Surman, Phil; Sexton, Ian; Bates, Richard; Lee, Wing Kai; Hopf, Klaus; Koukoulas, Triantaffilos

    2005-11-01

    De Montfort University, in conjunction with the Heinrich Hertz Institute, is developing a 3D display that is targeted specifically at the television market. It is capable of supplying 3D to several viewers who do not have to wear special glasses, and who are able to move freely over a room-sized area. The display consists of a single liquid crystal display that presents the same stereo pair to every viewer by employing spatial multiplexing. This presents a stereo pair on alternate pixel rows, with the conventional backlight replaced by novel steering optics controlled by the output of a head position tracker. Illumination is achieved using arrays of coaxial optical elements in conjunction with high-density white light emitting diode arrays. The operation of the steering and multiplexing optics in the prototype display are explained. The results obtained from a prototype built under the European Union-funded ATTEST 3D television project are described. The performance of this model was not optimum, but was sufficient to prove that the principle of operation is viable for a 3D television display. A second prototype, incorporating improvements based on experience gained, is currently under construction and this is also described. The prototype is capable of being developed into a display appropriate for a production model that will enable 3D television to come to market within the next ten years. With the current widespread usage of flat panel displays it is likely that customer preference will be for a hang-on-the-wall 3D display, and this challenge will be met by reconfiguring the optics and incorporating novel optical addressing techniques.

  6. Optical disk jukebox performance in multi-user applications

    NASA Astrophysics Data System (ADS)

    Hauser, Susan E.; Roy, Gautam; Thoma, George R.

    1994-10-01

    The Lister Hill National Center for Biomedical Communications, a research and development division of the National Library of Medicine, is evaluating an optical disk jukebox as a digital image store to support prototype systems for image distribution over the Internet. This paper summarizes a study undertaken to determine the performance characteristics of the jukebox to support multiple image databases simultaneously accessed by multiple users. A motivation for this investigation is the need to provide users access to digitized images of medical documents and radiographs.

  7. The Chief Diversity Officer

    ERIC Educational Resources Information Center

    Williams, Damon; Wade-Golden, Katrina

    2007-01-01

    Numerous institutions are moving toward the chief diversity officer model of leading and managing diversity in higher education. These officers carry formal administrative titles and ranks that range from vice president for institutional diversity to associate vice chancellor for diversity and climate and dean of diversity and academic engagement.…

  8. HUMAN MACHINE COOPERATIVE TELEROBOTICS

    SciTech Connect

    William R. Hamel; Spivey Douglass; Sewoong Kim; Pamela Murray; Yang Shou; Sriram Sridharan; Ge Zhang; Scott Thayer; Rajiv V. Dubey

    2003-06-30

    described as Human Machine Cooperative Telerobotics (HMCTR). The HMCTR combines the telerobot with robotic control techniques to improve the system efficiency and reliability in teleoperation mode. In this topical report, the control strategy, configuration and experimental results of Human Machines Cooperative Telerobotics (HMCTR), which modifies and limits the commands of human operator to follow the predefined constraints in the teleoperation mode, is described. The current implementation is a laboratory-scale system that will be incorporated into an engineering-scale system at the Oak Ridge National Laboratory in the future.

  9. 32 CFR 37.1260 - Cooperative agreement.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... REGULATIONS TECHNOLOGY INVESTMENT AGREEMENTS Definitions of Terms Used in This Part § 37.1260 Cooperative... the cooperative agreement. The term does not include “cooperative research and development...

  10. Different axes of environmental variation explain the presence versus extent of cooperative nest founding associations in Polistes paper wasps

    PubMed Central

    Sheehan, Michael J; Botero, Carlos A; Hendry, Tory A; Sedio, Brian E; Jandt, Jennifer M.; Weiner, Susan; Toth, Amy L; Tibbetts, Elizabeth A

    2015-01-01

    Ecological constraints on independent breeding are recognized as major drivers of cooperative breeding across diverse lineages. How the prevalence and degree of cooperative breeding relates to ecological variation remains unresolved. Using a large dataset on cooperative nesting in Polistes wasps we demonstrate that different aspects of cooperative breeding are likely to be driven by different aspects of climate. Whether or not a species forms cooperative groups is associated with greater short-term temperature fluctuations. In contrast, the number of cooperative foundresses increases in more benign environments with warmer, wetter conditions. The same dataset reveals that intraspecific responses to climate variation do not mirror genus-wide trends and instead are highly heterogeneous among species. Collectively these data suggest that the ecological drivers that lead to the origin or loss of cooperation are different from those that influence the extent of its expression within populations. PMID:26248800

  11. Different axes of environmental variation explain the presence vs. extent of cooperative nest founding associations in Polistes paper wasps.

    PubMed

    Sheehan, Michael J; Botero, Carlos A; Hendry, Tory A; Sedio, Brian E; Jandt, Jennifer M; Weiner, Susan; Toth, Amy L; Tibbetts, Elizabeth A

    2015-10-01

    Ecological constraints on independent breeding are recognised as major drivers of cooperative breeding across diverse lineages. How the prevalence and degree of cooperative breeding relates to ecological variation remains unresolved. Using a large data set of cooperative nesting in Polistes wasps we demonstrate that different aspects of cooperative breeding are likely to be driven by different aspects of climate. Whether or not a species forms cooperative groups is associated with greater short-term temperature fluctuations. In contrast, the number of cooperative foundresses increases in more benign environments with warmer, wetter conditions. The same data set reveals that intraspecific responses to climate variation do not mirror genus-wide trends and instead are highly heterogeneous among species. Collectively these data suggest that the ecological drivers that lead to the origin or loss of cooperation are different from those that influence the extent of its expression within populations.

  12. Laparoscopic endoscopic cooperative surgery.

    PubMed

    Hiki, Naoki; Nunobe, Souya; Matsuda, Tatsuo; Hirasawa, Toshiaki; Yamamoto, Yorimasa; Yamaguchi, Toshiharu

    2015-01-01

    Laparoscopic and endoscopic cooperative surgery (LECS) is a newly developed concept for tumor dissection of the gastrointestinal tract that was first investigated for local resection of gastric gastrointestinal stromal tumors (GIST). The first reported version of LECS for GIST has been named 'classical LECS' to distinguish it from other modified LECS procedures, such as inverted LECS, a combination of laparoscopic and endoscopic approaches to neoplasia with a non-exposure technique (CLEAN-NET), and non-exposed endoscopic wall-inversion surgery (NEWS). These modified LECS procedures were developed for dissection of malignant tumors which may seed tumor cells into the abdominal cavity. While these LECS-related procedures might prevent tumor seeding, their application is limited by several factors, such as tumor size, location and technical difficulty. Currently, classical LECS is a safe and useful procedure for gastric submucosal tumors without mucosal defects, independent of tumor location, such as proximity to the esophagogastric junction or pyloric ring. For future applications of LECS-related procedures for other malignant diseases with mucosal lesions such as GIST with mucosal defects and gastric cancer, some improvements in the techniques are needed.

  13. The coevolution of long-term pair bonds and cooperation.

    PubMed

    Song, Z; Feldman, M W

    2013-05-01

    The evolution of social traits may not only depend on but also change the social structure of the population. In particular, the evolution of pairwise cooperation, such as biparental care, depends on the pair-matching distribution of the population, and the latter often emerges as a collective outcome of individual pair-bonding traits, which are also under selection. Here, we develop an analytical model and individual-based simulations to study the coevolution of long-term pair bonds and cooperation in parental care, where partners play a Snowdrift game in each breeding season. We illustrate that long-term pair bonds may coevolve with cooperation when bonding cost is below a threshold. As long-term pair bonds lead to assortative interactions through pair-matching dynamics, they may promote the prevalence of cooperation. In addition to the pay-off matrix of a single game, the evolutionarily stable equilibrium also depends on bonding cost and accidental divorce rate, and it is determined by a form of balancing selection because the benefit from pair-bond maintenance diminishes as the frequency of cooperators increases. Our findings highlight the importance of ecological factors affecting social bonding cost and stability in understanding the coevolution of social behaviour and social structures, which may lead to the diversity of biological social systems. PMID:23496797

  14. The Hard Problem of Cooperation

    PubMed Central

    Eriksson, Kimmo; Strimling, Pontus

    2012-01-01

    Based on individual variation in cooperative inclinations, we define the “hard problem of cooperation” as that of achieving high levels of cooperation in a group of non-cooperative types. Can the hard problem be solved by institutions with monitoring and sanctions? In a laboratory experiment we find that the answer is affirmative if the institution is imposed on the group but negative if development of the institution is left to the group to vote on. In the experiment, participants were divided into groups of either cooperative types or non-cooperative types depending on their behavior in a public goods game. In these homogeneous groups they repeatedly played a public goods game regulated by an institution that incorporated several of the key properties identified by Ostrom: operational rules, monitoring, rewards, punishments, and (in one condition) change of rules. When change of rules was not possible and punishments were set to be high, groups of both types generally abided by operational rules demanding high contributions to the common good, and thereby achieved high levels of payoffs. Under less severe rules, both types of groups did worse but non-cooperative types did worst. Thus, non-cooperative groups profited the most from being governed by an institution demanding high contributions and employing high punishments. Nevertheless, in a condition where change of rules through voting was made possible, development of the institution in this direction was more often voted down in groups of non-cooperative types. We discuss the relevance of the hard problem and fit our results into a bigger picture of institutional and individual determinants of cooperative behavior. PMID:22792282

  15. Exploring Reputation-Based Cooperation:

    NASA Astrophysics Data System (ADS)

    Vilone, Daniele; Giardini, Francesca; Paolucci, Mario

    In dyadic models of indirect reciprocity, the receivers' history of giving has a significant impact on the donor's decision. When the interaction involves more than two agents things become more complicated, and in large groups cooperation can hardly emerge. In this work we use a Public Goods Game to investigate whether publicly available reputation scores may support the evolution of cooperation and whether this is affected by the kind of network structure adopted. Moreover, if agents interact on a bipartite graph with partner selection, cooperation can quickly thrive in large groups.

  16. Dare To Be You: A Diversion Program for First Time Juvenile Offenders.

    ERIC Educational Resources Information Center

    Vail, Ann; Nest, Judy

    This document notes that community-based organizations such as the Cooperative Extension Service have joined the efforts to reduce juvenile delinquency through juvenile diversion programs. It then describes the "Dare to be You" program that was developed by the Colorado Cooperative Extension System. The six objectives of the program delineated in…

  17. Cooperative robotic sentry vehicles

    NASA Astrophysics Data System (ADS)

    Feddema, John T.; Lewis, Christopher L.; Klarer, Paul; Eisler, G. R.; Caprihan, Rahul

    1999-08-01

    As part of a project for the Defense Advanced Research Projects Agency, Sandia National Laboratories' Intelligent Systems and Robotics Center is developing and testing the feasibility of a cooperative team of robotic sentry vehicles to guard a perimeter and to perform a surround task. This paper describes on-going activities in the development of these robotic sentry vehicles. To date, we have developed a robotic perimeter detection system which consists of eight 'Roving All Terrain Lunar Explorer Rovers' (RATLER), a laptop-based base-station, and several Miniature Intrusion Detection Sensors (MIDS). A radio frequency receiver on each of the RATLER vehicles alerts the sentry vehicles of alarms from the hidden MIDS. When an alarm is received, each vehicle decides whether it should investigate the alarm based on the proximity of itself and the other vehicles to the alarm. As one vehicle attends an alarm, the other vehicles adjust their position around the perimeter to better prepare for another alarm. For the surround task, both potential field and A* search path planners have been added to the base-station and vehicles. At the base-station, the operator specifies goal and exclusion regions on a GIS map. The path planner generates vehicles paths that are previewed by the operator. Once the operator has validated the path, the appropriate information is downloaded t the vehicles. For the potential field path planner, the polygons and line segments that represent the obstacles and goals are downloaded to the vehicles, instead of the simulated paths. On board the vehicles, the same potential field path planner generates the path except that it uses the true location of itself and the nearest neighboring vehicle. For the A* path planner, the actual path is downloaded to the vehicles because of limited on-board computational power.

  18. [Aware and cooperative reduction].

    PubMed

    Tambone, V; Ghilardi, G

    2012-01-01

    The aim of this work is to address the question of reduction in the scientific method, to evaluate its legitimacy as well as its pro and contra from an epistemological point of view. In the first paragraph we classify some kinds of reductionism, analysing their presuppositions and epistemological status and showing some examples of scientific reduction. The presentation includes a classificatory table that shows some of the different forms of biological reductionism. In the second paragraph we study the epistemology of science starting from its modern beginning: the Vienna Circle, focusing on the meaning of methodological reductionism. What did it mean for science to define itself mainly as method, which effects did this new concept of science have on methodology and what kind of problems did this movement bring about. In the third paragraph we examine the reactions triggered by methodological reductionism, we analyze the theoretical consistency of these answers, trying to offer a balanced view. We show how complexity can be seen as a paradigm of the anti-reductionism effort, and we study its epistemological basis. In the fourth paragraph we outline our operative proposal: the reduction that is both aware and cooperative. We point out the main reasons why science cannot avoid being reductive in some way, and therefore how we need to deal with this feature in order to prevent it to degenerate into reductionism. We show some examples of this new proposal taken from the practical realm and from literature, where it is possible to discern the spirit of this alternative methodology. PMID:22964706

  19. International cooperation in space transportation: Results of the AIAA Hawaii conference

    NASA Astrophysics Data System (ADS)

    Egan, J.

    In 1992, the International Committee of the AIAA sponsored a workshop in Hawaii entitled 'International Space Cooperation: Learning form the Past, Planning for the Future' which attempted to understand how the recent dramatic changes in the world situation might impact future international cooperation in space. This workshop formed the basis for a second workshop, also in Hawaii, entitled 'International Space Cooperation: Getting Serious about How' in December 1994. The second workshop built on the past findings and was designed to formulate approaches on how to make international cooperation work for a number of international space activities. A distinguished group of 65 experts from fifteen countries were organized into five working groups within the larger workshop to address five diverse areas: Global Space Systems Services, International Space Cooperation for Peacekeeping, Cooperative Human and Robotic Exploration of Space, International Cooperation in Space Transportation, and Solar Power to Earth dealing with near and longer term space projects where international cooperation might play a part. Work was conducted in both working group sessions and plenary sessions to stimulate and encourage the greatest exchange of ideas among the participants as possible. A report on the entire workship is available from the AIAA. The purpose of this paper is to report on the results of the International Cooperation in Space Transporation topic.

  20. Cooperative strings and glassy interfaces.

    PubMed

    Salez, Thomas; Salez, Justin; Dalnoki-Veress, Kari; Raphaël, Elie; Forrest, James A

    2015-07-01

    We introduce a minimal theory of glass formation based on the ideas of molecular crowding and resultant string-like cooperative rearrangement, and address the effects of free interfaces. In the bulk case, we obtain a scaling expression for the number of particles taking part in cooperative strings, and we recover the Adam-Gibbs description of glassy dynamics. Then, by including thermal dilatation, the Vogel-Fulcher-Tammann relation is derived. Moreover, the random and string-like characters of the cooperative rearrangement allow us to predict a temperature-dependent expression for the cooperative length ξ of bulk relaxation. Finally, we explore the influence of sample boundaries when the system size becomes comparable to ξ. The theory is in agreement with measurements of the glass-transition temperature of thin polymer films, and allows quantification of the temperature-dependent thickness hm of the interfacial mobile layer. PMID:26100908

  1. Interorganizational Cooperation: Why and How?

    ERIC Educational Resources Information Center

    Beder, Hal

    1984-01-01

    Describes characteristics of continuing education agencies (resource and organizational insecurity, need for flexibility, autonomy), type of cooperation (cosponsorship, referral, donation, coordination), essential resources (money, learners, staff, information, domain, power), hidden costs (time, dislocation, goal dislocation, goal displacement,…

  2. Cooperative strings and glassy interfaces.

    PubMed

    Salez, Thomas; Salez, Justin; Dalnoki-Veress, Kari; Raphaël, Elie; Forrest, James A

    2015-07-01

    We introduce a minimal theory of glass formation based on the ideas of molecular crowding and resultant string-like cooperative rearrangement, and address the effects of free interfaces. In the bulk case, we obtain a scaling expression for the number of particles taking part in cooperative strings, and we recover the Adam-Gibbs description of glassy dynamics. Then, by including thermal dilatation, the Vogel-Fulcher-Tammann relation is derived. Moreover, the random and string-like characters of the cooperative rearrangement allow us to predict a temperature-dependent expression for the cooperative length ξ of bulk relaxation. Finally, we explore the influence of sample boundaries when the system size becomes comparable to ξ. The theory is in agreement with measurements of the glass-transition temperature of thin polymer films, and allows quantification of the temperature-dependent thickness hm of the interfacial mobile layer.

  3. Future Directions in Cooperative Education.

    ERIC Educational Resources Information Center

    Leventhal, Jerome

    1996-01-01

    Current trends influencing cooperative education include the Workforce Development Act, the school-to-work career paths approach, use of multiple intelligences research in the classroom, and action research to improve program development. (SK)

  4. The Paradoxes of Library Cooperation

    ERIC Educational Resources Information Center

    Dougherty, Richard M.; And Others

    1972-01-01

    Besides the main article by Richard Dougherty, this mini-symposium on library cooperation contains commentaries by Ralph Blasingame, Thomas J. Galvin, Ellsworth Mason, John F. Anderson and Robert S. Ake. (18 references) (NH)

  5. Cooperative binding: a multiple personality.

    PubMed

    Martini, Johannes W R; Diambra, Luis; Habeck, Michael

    2016-06-01

    Cooperative binding has been described in many publications and has been related to or defined by several different properties of the binding behavior of the ligand to the target molecule. In addition to the commonly used Hill coefficient, other characteristics such as a sigmoidal shape of the overall titration curve in a linear plot, a change of ligand affinity of the other binding sites when a site of the target molecule becomes occupied, or complex roots of the binding polynomial have been used to define or to quantify cooperative binding. In this work, we analyze how the different properties are related in the most general model for binding curves based on the grand canonical partition function and present several examples which highlight differences between the cooperativity characterizing properties which are discussed. Our results mainly show that among the presented definitions there are not two which fully coincide. Moreover, this work poses the question whether it can make sense to distinguish between positive and negative cooperativity based on the macroscopic binding isotherm only. This article shall emphasize that scientists who investigate cooperative effects in biological systems could help avoiding misunderstandings by stating clearly which kind of cooperativity they discuss.

  6. How feeling betrayed affects cooperation.

    PubMed

    Ramazi, Pouria; Hessel, Jop; Cao, Ming

    2015-01-01

    For a population of interacting self-interested agents, we study how the average cooperation level is affected by some individuals' feelings of being betrayed and guilt. We quantify these feelings as adjusted payoffs in asymmetric games, where for different emotions, the payoff matrix takes the structure of that of either a prisoner's dilemma or a snowdrift game. Then we analyze the evolution of cooperation in a well-mixed population of agents, each of whom is associated with such a payoff matrix. At each time-step, an agent is randomly chosen from the population to update her strategy based on the myopic best-response update rule. According to the simulations, decreasing the feeling of being betrayed in a portion of agents does not necessarily increase the level of cooperation in the population. However, this resistance of the population against low-betrayal-level agents is effective only up to some extend that is explicitly determined by the payoff matrices and the number of agents associated with these matrices. Two other models are also considered where the betrayal factor of an agent fluctuates as a function of the number of cooperators and defectors that she encounters. Unstable behaviors are observed for the level of cooperation in these cases; however, we show that one can tune the parameters in the function to make the whole population become cooperative or defective. PMID:25922933

  7. Human uniqueness-self-interest and social cooperation.

    PubMed

    Okada, Daijiro; Bingham, Paul M

    2008-07-21

    Humans are unique among all species of terrestrial history in both ecological dominance and individual properties. Many, or perhaps all, of the unique elements of this nonpareil status can be plausibly interpreted as evolutionary and strategic elements and consequences of the unprecedented intensity and scale of our social cooperation. Convincing explanation of this unique human social adaptation remains a central, unmet challenge to the scientific enterprise. We develop a hypothesis for the ancestral origin of expanded cooperative social behavior. Specifically, we present a game theoretic analysis demonstrating that a specific pattern of expanded social cooperation between conspecific individuals with conflicts of interest (including non-kin) can be strategically viable, but only in animals that possess a highly unusual capacity for conspecific violence (credible threat) having very specific properties that dramatically reduce the costs of coercive violence. The resulting reduced costs allow preemptive or compensated coercion to be an instantaneously self-interested behavior under diverse circumstances rather than in rare, idiosyncratic circumstances as in actors (animals) who do not have access to inexpensive coercive threat. Humans are apparently unique among terrestrial organisms in having evolved conspecific coercive capabilities that fulfill these stringent requirements. Thus, our results support the proposal that access to a novel capacity for projection of coercive threat might represent the essential initiating event for the evolution of a human-like pattern of social cooperation and the subsequent evolution of the diverse features of human uniqueness. Empirical evidence indicates that these constraints were, in fact, met only in our evolutionary lineage. The logic for the emergence of uniquely human cooperation suggested by our analysis apparently accounts simply for the human fossil record. PMID:18462758

  8. 10 CFR 745.114 - Cooperative research.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Cooperative research. 745.114 Section 745.114 Energy DEPARTMENT OF ENERGY PROTECTION OF HUMAN SUBJECTS § 745.114 Cooperative research. Cooperative research... of cooperative research projects, each institution is responsible for safeguarding the rights...

  9. 45 CFR 690.114 - Cooperative research.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 45 Public Welfare 3 2010-10-01 2010-10-01 false Cooperative research. 690.114 Section 690.114... OF HUMAN SUBJECTS § 690.114 Cooperative research. Cooperative research projects are those projects covered by this policy which involve more than one institution. In the conduct of cooperative...

  10. 15 CFR 27.114 - Cooperative research.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 15 Commerce and Foreign Trade 1 2010-01-01 2010-01-01 false Cooperative research. 27.114 Section... § 27.114 Cooperative research. Cooperative research projects are those projects covered by this policy which involve more than one institution. In the conduct of cooperative research projects,...

  11. 16 CFR 1028.114 - Cooperative research.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Cooperative research. 1028.114 Section 1028... § 1028.114 Cooperative research. Cooperative research projects are those projects covered by this policy which involve more than one institution. In the conduct of cooperative research projects,...

  12. 28 CFR 46.114 - Cooperative research.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Cooperative research. 46.114 Section 46... Cooperative research. Cooperative research projects are those projects covered by this policy which involve more than one institution. In the conduct of cooperative research projects, each institution...

  13. 32 CFR 219.114 - Cooperative research.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 2 2010-07-01 2010-07-01 false Cooperative research. 219.114 Section 219.114...) MISCELLANEOUS PROTECTION OF HUMAN SUBJECTS § 219.114 Cooperative research. Cooperative research projects are... cooperative research projects, each institution is responsible for safeguarding the rights and welfare...

  14. 38 CFR 16.114 - Cooperative research.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Cooperative research. 16... OF HUMAN SUBJECTS § 16.114 Cooperative research. Cooperative research projects are those projects covered by this policy which involve more than one institution. In the conduct of cooperative...

  15. 32 CFR 219.114 - Cooperative research.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 2 2013-07-01 2013-07-01 false Cooperative research. 219.114 Section 219.114...) MISCELLANEOUS PROTECTION OF HUMAN SUBJECTS § 219.114 Cooperative research. Cooperative research projects are... cooperative research projects, each institution is responsible for safeguarding the rights and welfare...

  16. 10 CFR 745.114 - Cooperative research.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 4 2013-01-01 2013-01-01 false Cooperative research. 745.114 Section 745.114 Energy DEPARTMENT OF ENERGY PROTECTION OF HUMAN SUBJECTS § 745.114 Cooperative research. Cooperative research... of cooperative research projects, each institution is responsible for safeguarding the rights...

  17. 15 CFR 27.114 - Cooperative research.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 15 Commerce and Foreign Trade 1 2014-01-01 2014-01-01 false Cooperative research. 27.114 Section... § 27.114 Cooperative research. Cooperative research projects are those projects covered by this policy which involve more than one institution. In the conduct of cooperative research projects,...

  18. 15 CFR 27.114 - Cooperative research.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 15 Commerce and Foreign Trade 1 2013-01-01 2013-01-01 false Cooperative research. 27.114 Section... § 27.114 Cooperative research. Cooperative research projects are those projects covered by this policy which involve more than one institution. In the conduct of cooperative research projects,...

  19. 16 CFR 1028.114 - Cooperative research.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 16 Commercial Practices 2 2014-01-01 2014-01-01 false Cooperative research. 1028.114 Section 1028... § 1028.114 Cooperative research. Cooperative research projects are those projects covered by this policy which involve more than one institution. In the conduct of cooperative research projects,...

  20. 16 CFR 1028.114 - Cooperative research.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 16 Commercial Practices 2 2013-01-01 2013-01-01 false Cooperative research. 1028.114 Section 1028... § 1028.114 Cooperative research. Cooperative research projects are those projects covered by this policy which involve more than one institution. In the conduct of cooperative research projects,...

  1. 32 CFR 219.114 - Cooperative research.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 2 2012-07-01 2012-07-01 false Cooperative research. 219.114 Section 219.114...) MISCELLANEOUS PROTECTION OF HUMAN SUBJECTS § 219.114 Cooperative research. Cooperative research projects are... cooperative research projects, each institution is responsible for safeguarding the rights and welfare...

  2. 38 CFR 16.114 - Cooperative research.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2013-07-01 2013-07-01 false Cooperative research. 16... OF HUMAN SUBJECTS § 16.114 Cooperative research. Cooperative research projects are those projects covered by this policy which involve more than one institution. In the conduct of cooperative...

  3. 28 CFR 46.114 - Cooperative research.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 28 Judicial Administration 2 2013-07-01 2013-07-01 false Cooperative research. 46.114 Section 46... Cooperative research. Cooperative research projects are those projects covered by this policy which involve more than one institution. In the conduct of cooperative research projects, each institution...

  4. 28 CFR 46.114 - Cooperative research.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 28 Judicial Administration 2 2012-07-01 2012-07-01 false Cooperative research. 46.114 Section 46... Cooperative research. Cooperative research projects are those projects covered by this policy which involve more than one institution. In the conduct of cooperative research projects, each institution...

  5. 32 CFR 219.114 - Cooperative research.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 2 2014-07-01 2014-07-01 false Cooperative research. 219.114 Section 219.114...) MISCELLANEOUS PROTECTION OF HUMAN SUBJECTS § 219.114 Cooperative research. Cooperative research projects are... cooperative research projects, each institution is responsible for safeguarding the rights and welfare...

  6. 38 CFR 16.114 - Cooperative research.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2014-07-01 2014-07-01 false Cooperative research. 16... OF HUMAN SUBJECTS § 16.114 Cooperative research. Cooperative research projects are those projects covered by this policy which involve more than one institution. In the conduct of cooperative...

  7. 45 CFR 690.114 - Cooperative research.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 45 Public Welfare 3 2014-10-01 2014-10-01 false Cooperative research. 690.114 Section 690.114... OF HUMAN SUBJECTS § 690.114 Cooperative research. Cooperative research projects are those projects covered by this policy which involve more than one institution. In the conduct of cooperative...

  8. 45 CFR 690.114 - Cooperative research.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 45 Public Welfare 3 2012-10-01 2012-10-01 false Cooperative research. 690.114 Section 690.114... OF HUMAN SUBJECTS § 690.114 Cooperative research. Cooperative research projects are those projects covered by this policy which involve more than one institution. In the conduct of cooperative...

  9. 10 CFR 745.114 - Cooperative research.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 4 2014-01-01 2014-01-01 false Cooperative research. 745.114 Section 745.114 Energy DEPARTMENT OF ENERGY PROTECTION OF HUMAN SUBJECTS § 745.114 Cooperative research. Cooperative research... of cooperative research projects, each institution is responsible for safeguarding the rights...

  10. 10 CFR 745.114 - Cooperative research.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 4 2012-01-01 2012-01-01 false Cooperative research. 745.114 Section 745.114 Energy DEPARTMENT OF ENERGY PROTECTION OF HUMAN SUBJECTS § 745.114 Cooperative research. Cooperative research... of cooperative research projects, each institution is responsible for safeguarding the rights...

  11. 15 CFR 27.114 - Cooperative research.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 15 Commerce and Foreign Trade 1 2012-01-01 2012-01-01 false Cooperative research. 27.114 Section... § 27.114 Cooperative research. Cooperative research projects are those projects covered by this policy which involve more than one institution. In the conduct of cooperative research projects,...

  12. 38 CFR 16.114 - Cooperative research.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2012-07-01 2012-07-01 false Cooperative research. 16... OF HUMAN SUBJECTS § 16.114 Cooperative research. Cooperative research projects are those projects covered by this policy which involve more than one institution. In the conduct of cooperative...

  13. 45 CFR 690.114 - Cooperative research.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 45 Public Welfare 3 2013-10-01 2013-10-01 false Cooperative research. 690.114 Section 690.114... OF HUMAN SUBJECTS § 690.114 Cooperative research. Cooperative research projects are those projects covered by this policy which involve more than one institution. In the conduct of cooperative...

  14. 28 CFR 46.114 - Cooperative research.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 28 Judicial Administration 2 2014-07-01 2014-07-01 false Cooperative research. 46.114 Section 46... Cooperative research. Cooperative research projects are those projects covered by this policy which involve more than one institution. In the conduct of cooperative research projects, each institution...

  15. 16 CFR 1028.114 - Cooperative research.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 16 Commercial Practices 2 2012-01-01 2012-01-01 false Cooperative research. 1028.114 Section 1028... § 1028.114 Cooperative research. Cooperative research projects are those projects covered by this policy which involve more than one institution. In the conduct of cooperative research projects,...

  16. 38 CFR 16.114 - Cooperative research.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2011-07-01 2011-07-01 false Cooperative research. 16... OF HUMAN SUBJECTS § 16.114 Cooperative research. Cooperative research projects are those projects covered by this policy which involve more than one institution. In the conduct of cooperative...

  17. 28 CFR 46.114 - Cooperative research.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 28 Judicial Administration 2 2011-07-01 2011-07-01 false Cooperative research. 46.114 Section 46... Cooperative research. Cooperative research projects are those projects covered by this policy which involve more than one institution. In the conduct of cooperative research projects, each institution...

  18. 16 CFR 1028.114 - Cooperative research.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 16 Commercial Practices 2 2011-01-01 2011-01-01 false Cooperative research. 1028.114 Section 1028... § 1028.114 Cooperative research. Cooperative research projects are those projects covered by this policy which involve more than one institution. In the conduct of cooperative research projects,...

  19. 32 CFR 219.114 - Cooperative research.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 2 2011-07-01 2011-07-01 false Cooperative research. 219.114 Section 219.114...) MISCELLANEOUS PROTECTION OF HUMAN SUBJECTS § 219.114 Cooperative research. Cooperative research projects are... cooperative research projects, each institution is responsible for safeguarding the rights and welfare...

  20. 10 CFR 745.114 - Cooperative research.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 4 2011-01-01 2011-01-01 false Cooperative research. 745.114 Section 745.114 Energy DEPARTMENT OF ENERGY PROTECTION OF HUMAN SUBJECTS § 745.114 Cooperative research. Cooperative research... of cooperative research projects, each institution is responsible for safeguarding the rights...

  1. 15 CFR 27.114 - Cooperative research.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 15 Commerce and Foreign Trade 1 2011-01-01 2011-01-01 false Cooperative research. 27.114 Section... § 27.114 Cooperative research. Cooperative research projects are those projects covered by this policy which involve more than one institution. In the conduct of cooperative research projects,...

  2. 36 CFR 212.3 - Cooperative work.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 2 2014-07-01 2014-07-01 false Cooperative work. 212.3... MANAGEMENT Administration of the Forest Transportation System § 212.3 Cooperative work. (a) Cooperative... for expenditure from the appropriation “Cooperative Work, Forest Service.” If a State, county or...

  3. 36 CFR 212.3 - Cooperative work.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 36 Parks, Forests, and Public Property 2 2013-07-01 2013-07-01 false Cooperative work. 212.3... MANAGEMENT Administration of the Forest Transportation System § 212.3 Cooperative work. (a) Cooperative... for expenditure from the appropriation “Cooperative Work, Forest Service.” If a State, county or...

  4. 36 CFR 212.3 - Cooperative work.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 36 Parks, Forests, and Public Property 2 2011-07-01 2011-07-01 false Cooperative work. 212.3... MANAGEMENT Administration of the Forest Transportation System § 212.3 Cooperative work. (a) Cooperative... for expenditure from the appropriation “Cooperative Work, Forest Service.” If a State, county or...

  5. 36 CFR 212.3 - Cooperative work.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 2 2010-07-01 2010-07-01 false Cooperative work. 212.3... MANAGEMENT Administration of the Forest Transportation System § 212.3 Cooperative work. (a) Cooperative... for expenditure from the appropriation “Cooperative Work, Forest Service.” If a State, county or...

  6. 36 CFR 212.3 - Cooperative work.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 36 Parks, Forests, and Public Property 2 2012-07-01 2012-07-01 false Cooperative work. 212.3... MANAGEMENT Administration of the Forest Transportation System § 212.3 Cooperative work. (a) Cooperative... for expenditure from the appropriation “Cooperative Work, Forest Service.” If a State, county or...

  7. 7 CFR 1000.18 - Cooperative association.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 9 2011-01-01 2011-01-01 false Cooperative association. 1000.18 Section 1000.18... Definitions § 1000.18 Cooperative association. Cooperative association means any cooperative marketing association of producers which the Secretary determines is qualified under the provisions of the...

  8. 7 CFR 1150.119 - Cooperative association.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 9 2011-01-01 2011-01-01 false Cooperative association. 1150.119 Section 1150.119... Order Definitions § 1150.119 Cooperative association. Cooperative association means any cooperative marketing association of producers which is organized under the provisions of the Act of Congress...

  9. 7 CFR 1000.18 - Cooperative association.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Cooperative association. 1000.18 Section 1000.18... Definitions § 1000.18 Cooperative association. Cooperative association means any cooperative marketing association of producers which the Secretary determines is qualified under the provisions of the...

  10. 7 CFR 1150.119 - Cooperative association.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Cooperative association. 1150.119 Section 1150.119... Order Definitions § 1150.119 Cooperative association. Cooperative association means any cooperative marketing association of producers which is organized under the provisions of the Act of Congress...

  11. 43 CFR 418.18 - Diversions at Derby Dam.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Dam must be managed to maintain minimum terminal flow to Lahontan Reservoir or the Carson River except... achieve an average terminal flow of 20 cfs or less during times when diversions to Lahontan Reservoir are... releases from Stampede Reservoir and other reservoirs, in cooperation with the Federal Water Master,...

  12. The Positive Educational Effects of Racial Diversity on Campus.

    ERIC Educational Resources Information Center

    Chang, Mitchell J.

    This study examined links between racial diversity on college campuses and positive educational outcomes. Data came from the Cooperative Institutional Research Program database, a longitudinal set of student and faculty surveys and research that assessed the impact of college on students. This study used data from a 1985 freshman survey and the…

  13. Population dynamics of obligate cooperators

    PubMed Central

    Courchamp, F.; Grenfell, B.; Clutton-Brock, T.

    1999-01-01

    Obligate cooperative breeding species demonstrate a high rate of group extinction, which may be due to the existence of a critical number of helpers below which the group cannot subsist. Through a simple model, we study the population dynamics of obligate cooperative breeding species, taking into account the existence of a lower threshold below which the instantaneous growth rate becomes negative. The model successively incorporates (i) a distinction between species that need helpers for reproduction, survival or both, (ii) the existence of a migration rate accounting for dispersal, and (iii) stochastic mortality to simulate the effects of random catastrophic events. Our results suggest that the need for a minimum number of helpers increases the risk of extinction for obligate cooperative breeding species. The constraint imposed by this threshold is higher when helpers are needed for reproduction only or for both reproduction and survival. By driving them below this lower threshold, stochastic mortality of lower amplitude and/or lower frequency than for non-cooperative breeders may be sufficient to cause the extinction of obligate cooperative breeding groups. Migration may have a buffering effect only for groups where immigration is higher than emigration; otherwise (when immigrants from nearby groups are not available) it lowers the difference between actual group size and critical threshold, thereby constituting a higher constraint.

  14. The Globalization of Cooperative Groups.

    PubMed

    Valdivieso, Manuel; Corn, Benjamin W; Dancey, Janet E; Wickerham, D Lawrence; Horvath, L Elise; Perez, Edith A; Urton, Alison; Cronin, Walter M; Field, Erica; Lackey, Evonne; Blanke, Charles D

    2015-10-01

    The National Cancer Institute (NCI)-supported adult cooperative oncology research groups (now officially Network groups) have a longstanding history of participating in international collaborations throughout the world. Most frequently, the US-based cooperative groups work reciprocally with the Canadian national adult cancer clinical trial group, NCIC CTG (previously the National Cancer Institute of Canada Clinical Trials Group). Thus, Canada is the largest contributor to cooperative groups based in the United States, and vice versa. Although international collaborations have many benefits, they are most frequently utilized to enhance patient accrual to large phase III trials originating in the United States or Canada. Within the cooperative group setting, adequate attention has not been given to the study of cancers that are unique to countries outside the United States and Canada, such as those frequently associated with infections in Latin America, Asia, and Africa. Global collaborations are limited by a number of barriers, some of which are unique to the countries involved, while others are related to financial support and to US policies that restrict drug distribution outside the United States. This article serves to detail the cooperative group experience in international research and describe how international collaboration in cancer clinical trials is a promising and important area that requires greater consideration in the future. PMID:26433551

  15. The Globalization of Cooperative Groups.

    PubMed

    Valdivieso, Manuel; Corn, Benjamin W; Dancey, Janet E; Wickerham, D Lawrence; Horvath, L Elise; Perez, Edith A; Urton, Alison; Cronin, Walter M; Field, Erica; Lackey, Evonne; Blanke, Charles D

    2015-10-01

    The National Cancer Institute (NCI)-supported adult cooperative oncology research groups (now officially Network groups) have a longstanding history of participating in international collaborations throughout the world. Most frequently, the US-based cooperative groups work reciprocally with the Canadian national adult cancer clinical trial group, NCIC CTG (previously the National Cancer Institute of Canada Clinical Trials Group). Thus, Canada is the largest contributor to cooperative groups based in the United States, and vice versa. Although international collaborations have many benefits, they are most frequently utilized to enhance patient accrual to large phase III trials originating in the United States or Canada. Within the cooperative group setting, adequate attention has not been given to the study of cancers that are unique to countries outside the United States and Canada, such as those frequently associated with infections in Latin America, Asia, and Africa. Global collaborations are limited by a number of barriers, some of which are unique to the countries involved, while others are related to financial support and to US policies that restrict drug distribution outside the United States. This article serves to detail the cooperative group experience in international research and describe how international collaboration in cancer clinical trials is a promising and important area that requires greater consideration in the future.

  16. The Globalization of Cooperative Groups

    PubMed Central

    Valdivieso, Manuel; Corn, Benjamin W.; Dancey, Janet E.; Wickerham, D. Lawrence; Horvath, L. Elise; Perez, Edith A.; Urton, Alison; Cronin, Walter M.; Field, Erica; Lackey, Evonne; Blanke, Charles D.

    2015-01-01

    The National Cancer Institute-supported adult cooperative oncology research groups (now officially Network groups) have a long-standing history of participating in international collaborations throughout the world. Most frequently, the U.S. based cooperative groups work reciprocally with the Canadian national adult cancer clinical trial group, NCIC CTG (previously the National Cancer Institute of Canada Clinical Trials Group). Thus, Canada is the largest contributor to cooperative groups based in the U.S., and vice versa. Although international collaborations have many benefits, they are most frequently utilized to enhance patient accrual to large phase III trials originating in the U.S. or Canada. Within the cooperative group setting, adequate attention has not been given to the study of cancers that are unique to countries outside the U.S. and Canada, such as those frequently associated with infections in Latin America, Asia and Africa. Global collaborations are limited by a number of barriers, some of which are unique to the countries involved, while others are related to financial support and to U.S. policies that restrict drug distribution outside the U.S. This manuscript serves to detail the cooperative group experience in international research and describe how international collaboration in cancer clinical trials is a promising and important area that requires greater consideration in the future. PMID:26433551

  17. Capturing the Diversity in Lexical Diversity

    ERIC Educational Resources Information Center

    Jarvis, Scott

    2013-01-01

    The range, variety, or diversity of words found in learners' language use is believed to reflect the complexity of their vocabulary knowledge as well as the level of their language proficiency. Many indices of lexical diversity have been proposed, most of which involve statistical relationships between types and tokens, and which ultimately…

  18. Diversity Statements: How Faculty Applicants Address Diversity

    ERIC Educational Resources Information Center

    Schmaling, Karen B.; Trevino, Amira Y.; Lind, Justin R.; Blume, Arthur W.; Baker, Dana L.

    2015-01-01

    The purpose of the present study was to examine application materials for assistant professor positions in 3 academic disciplines. Applicants were asked to write a diversity statement describing how they would advance diversity through their research, teaching, and service. The sample included application materials submitted by 191 candidates for…

  19. Does Staff Diversity Imply Openness to Diversity?

    ERIC Educational Resources Information Center

    Lauring, Jakob; Selmer, Jan

    2013-01-01

    Purpose: Post-secondary educational organizations are currently some of the most diverse settings to be found. However, few educational studies have dealt with staff diversity and hardly any has looked outside the USA. The purpose of this paper is to present a study of members of international university departments in Denmark. The authors set out…

  20. Distributed Relay Selection for MIMO-SDM Cooperative Networks

    NASA Astrophysics Data System (ADS)

    Tran, Xuan Nam; Nguyen, Vinh Hanh; Bui, Thanh Tam; Dinh, The Cuong; Karasawa, Yoshio

    In this paper, we consider an amplify-and-forward cooperative wireless network in which network nodes use multiple input multiple output (MIMO) spatial division multiplexing (SDM) to communicate with one another. We examine the problem of distributed cooperative relay selection and signal combining at the destination. First, we propose three distributed relay selection algorithms based on the maximum channel gains, the maximum harmonic mean of the channel gains, and the minimum mean squared error (MSE) of the signal estimation. Second, we propose a minimum mean square error (MMSE) signal combining scheme which jointly serves as the optimal signal combiner and interference canceler. It is shown that the MSE selection together with the MMSE combining achieves the maximal diversity gain. We also show that in MIMO-SDM cooperative networks increasing the number of candidate nodes does not help to improve the BER performance as opposed to the cooperative networks where each node is equipped with only single antenna. A practical approach to implementation of the combiner based on the current wireless access network protocols will also be presented.

  1. Cooperation, quorum sensing, and evolution of virulence in Staphylococcus aureus.

    PubMed

    Pollitt, Eric J G; West, Stuart A; Crusz, Shanika A; Burton-Chellew, Maxwell N; Diggle, Stephen P

    2014-03-01

    The virulence and fitness in vivo of the major human pathogen Staphylococcus aureus are associated with a cell-to-cell signaling mechanism known as quorum sensing (QS). QS coordinates the production of virulence factors via the production and sensing of autoinducing peptide (AIP) signal molecules by the agr locus. Here we show, in a wax moth larva virulence model, that (i) QS in S. aureus is a cooperative social trait that provides a benefit to the local population of cells, (ii) agr mutants, which do not produce or respond to QS signal, are able to exploit the benefits provided by the QS of others ("cheat"), allowing them to increase in frequency when in mixed populations with cooperators, (iii) these social interactions between cells determine virulence, with the host mortality rate being negatively correlated to the percentage of agr mutants ("cheats") in a population, and (iv) a higher within-host relatedness (lower strain diversity) selects for QS and hence higher virulence. Our results provide an explanation for why agr mutants show reduced virulence in animal models but can be isolated from infections of humans. More generally, by providing the first evidence that QS is a cooperative social behavior in a Gram-positive bacterium, our results suggest convergent, and potentially widespread, evolution for signaling to coordinate cooperation in bacteria. PMID:24343650

  2. Cooperative mission execution and planning

    NASA Astrophysics Data System (ADS)

    Flann, Nicholas S.; Saunders, Kevin S.; Pells, Larry

    1998-08-01

    Utilizing multiple cooperating autonomous vehicles to perform tasks enhances robustness and efficiency over the use of a single vehicle. Furthermore, because autonomous vehicles can be controlled precisely and their status known accurately in real time, new types of cooperative behaviors are possible. This paper presents a working system called MEPS that plans and executes missions for multiple autonomous vehicles in large structured environments. Two generic spatial tasks are supported, to sweep an area and to visit a location while activating on-board equipment. Tasks can be entered both initially by the user and dynamically during mission execution by both users and vehicles. Sensor data and task achievement data is shared among the vehicles enabling them to cooperatively adapt to changing environmental, vehicle and tasks conditions. The system has been successfully applied to control ATV and micro-robotic vehicles in precision agriculture and waste-site characterization environments.

  3. Cooperative program for Asian pediatricians.

    PubMed

    Sakakihara, Y; Nakamura, Y

    1993-12-01

    The Cooperative Program for Asian Pediatricians (CPAP) is a non-government organization established in 1989 to promote mutual understanding and friendship among young pediatricians in Asian countries. Unlike other government programs and non-government organizations, CPAP is solely facilitating mutual relationships among young inexperienced pediatricians who would otherwise have no chance to travel overseas. It has been funded by donations from members of the alumni association of the Department of Pediatrics at the University of Tokyo and many private companies and individuals. The Cooperative Program for Asian Pediatricians has so far invited 36 Asian pediatricians from 11 countries. By constructing a human network among Asian pediatricians, it is hoped that CPAP will contribute to making international cooperation in the Asian region easier and smoother.

  4. Fashion, Cooperation, and Social Interactions

    PubMed Central

    Cao, Zhigang; Gao, Haoyu; Qu, Xinglong; Yang, Mingmin; Yang, Xiaoguang

    2013-01-01

    Fashion plays such a crucial rule in the evolution of culture and society that it is regarded as a second nature to the human being. Also, its impact on economy is quite nontrivial. On what is fashionable, interestingly, there are two viewpoints that are both extremely widespread but almost opposite: conformists think that what is popular is fashionable, while rebels believe that being different is the essence. Fashion color is fashionable in the first sense, and Lady Gaga in the second. We investigate a model where the population consists of the afore-mentioned two groups of people that are located on social networks (a spatial cellular automata network and small-world networks). This model captures two fundamental kinds of social interactions (coordination and anti-coordination) simultaneously, and also has its own interest to game theory: it is a hybrid model of pure competition and pure cooperation. This is true because when a conformist meets a rebel, they play the zero sum matching pennies game, which is pure competition. When two conformists (rebels) meet, they play the (anti-) coordination game, which is pure cooperation. Simulation shows that simple social interactions greatly promote cooperation: in most cases people can reach an extraordinarily high level of cooperation, through a selfish, myopic, naive, and local interacting dynamic (the best response dynamic). We find that degree of synchronization also plays a critical role, but mostly on the negative side. Four indices, namely cooperation degree, average satisfaction degree, equilibrium ratio and complete ratio, are defined and applied to measure people’s cooperation levels from various angles. Phase transition, as well as emergence of many interesting geographic patterns in the cellular automata network, is also observed. PMID:23382799

  5. Fashion, cooperation, and social interactions.

    PubMed

    Cao, Zhigang; Gao, Haoyu; Qu, Xinglong; Yang, Mingmin; Yang, Xiaoguang

    2013-01-01

    Fashion plays such a crucial rule in the evolution of culture and society that it is regarded as a second nature to the human being. Also, its impact on economy is quite nontrivial. On what is fashionable, interestingly, there are two viewpoints that are both extremely widespread but almost opposite: conformists think that what is popular is fashionable, while rebels believe that being different is the essence. Fashion color is fashionable in the first sense, and Lady Gaga in the second. We investigate a model where the population consists of the afore-mentioned two groups of people that are located on social networks (a spatial cellular automata network and small-world networks). This model captures two fundamental kinds of social interactions (coordination and anti-coordination) simultaneously, and also has its own interest to game theory: it is a hybrid model of pure competition and pure cooperation. This is true because when a conformist meets a rebel, they play the zero sum matching pennies game, which is pure competition. When two conformists (rebels) meet, they play the (anti-) coordination game, which is pure cooperation. Simulation shows that simple social interactions greatly promote cooperation: in most cases people can reach an extraordinarily high level of cooperation, through a selfish, myopic, naive, and local interacting dynamic (the best response dynamic). We find that degree of synchronization also plays a critical role, but mostly on the negative side. Four indices, namely cooperation degree, average satisfaction degree, equilibrium ratio and complete ratio, are defined and applied to measure people's cooperation levels from various angles. Phase transition, as well as emergence of many interesting geographic patterns in the cellular automata network, is also observed. PMID:23382799

  6. Fashion, cooperation, and social interactions.

    PubMed

    Cao, Zhigang; Gao, Haoyu; Qu, Xinglong; Yang, Mingmin; Yang, Xiaoguang

    2013-01-01

    Fashion plays such a crucial rule in the evolution of culture and society that it is regarded as a second nature to the human being. Also, its impact on economy is quite nontrivial. On what is fashionable, interestingly, there are two viewpoints that are both extremely widespread but almost opposite: conformists think that what is popular is fashionable, while rebels believe that being different is the essence. Fashion color is fashionable in the first sense, and Lady Gaga in the second. We investigate a model where the population consists of the afore-mentioned two groups of people that are located on social networks (a spatial cellular automata network and small-world networks). This model captures two fundamental kinds of social interactions (coordination and anti-coordination) simultaneously, and also has its own interest to game theory: it is a hybrid model of pure competition and pure cooperation. This is true because when a conformist meets a rebel, they play the zero sum matching pennies game, which is pure competition. When two conformists (rebels) meet, they play the (anti-) coordination game, which is pure cooperation. Simulation shows that simple social interactions greatly promote cooperation: in most cases people can reach an extraordinarily high level of cooperation, through a selfish, myopic, naive, and local interacting dynamic (the best response dynamic). We find that degree of synchronization also plays a critical role, but mostly on the negative side. Four indices, namely cooperation degree, average satisfaction degree, equilibrium ratio and complete ratio, are defined and applied to measure people's cooperation levels from various angles. Phase transition, as well as emergence of many interesting geographic patterns in the cellular automata network, is also observed.

  7. Precision Manipulation with Cooperative Robots

    NASA Technical Reports Server (NTRS)

    Stroupe, Ashley; Huntsberger, Terry; Okon, Avi; Aghzarian, Hrand

    2005-01-01

    This work addresses several challenges of cooperative transportThis work addresses several challenges of cooperative transport and precision manipulation. Precision manipulation requires a rigid grasp, which places a hard constraint on the relative rover formation that must be accommodated, even though the rovers cannot directly observe their relative poses. Additionally, rovers must jointly select appropriate actions based on all available sensor information. Lastly, rovers cannot act on independent sensor information, but must fuse information to move jointly; the methods for fusing information must be determined.

  8. Co-Operative Education or Co-Operative Placement?

    ERIC Educational Resources Information Center

    Dickson, C. R.

    The Co-operative Education Department at Mohawk College is designed to extend the academic learning process into the workplace through on-the-job learning experiences which enhance the students' vocational maturation and personal development, and are integrated with the learning objectives of the program. The department offers paid, supervised…

  9. Bridging the Gap: Teachers Cooperating Together to Implement Cooperative Learning

    ERIC Educational Resources Information Center

    Jolliffe, Wendy

    2015-01-01

    Cooperative learning (CL), in spite of extensive research and documented benefits, is not widely used in England. A review of the literature shows that it requires a staged and sustained approach to implementation, which has led to a gap between its potential and actual use. The case study cited here provides one example of bridging that gap…

  10. HANDBOOK FOR DIVERSIFIED COOPERATIVE TRAINING. DISTRIBUTIVE, COOPERATIVE, AND BUSINESS EDUCATION.

    ERIC Educational Resources Information Center

    LOWMAN, C.L.

    THIS HANDBOOK WAS WRITTEN TO AID THE SCHOOL ADMINISTRATOR AND COORDINATOR IN ESTABLISHING AND OPERATING A DIVERSIFIED COOPERATIVE TRAINING (DCT) PROGRAM. THE DCT PROGRAM INVOLVES THE TRAINING OF HIGH SCHOOL STUDENTS IN THREE GENERAL OCCUPATIONAL GROUPS--TRADE AND INDUSTRIAL, DISTRIBUTIVE, AND OFFICE OCCUPATIONS. IF SPECIALIZED PROGRAMS IN…

  11. Diversity begets diversity? The effects of board composition on the appointment and success of women CEOs.

    PubMed

    Cook, Alison; Glass, Christy

    2015-09-01

    Previous research on the effects of leadership diversity on firm outcomes has produced inconsistent and inconclusive findings. While some scholars argue that diversity increases organizational equity and enhances performance, others argue that diversity increases conflict, reduces cooperation and harms performance. This study tests the impact of a variety of compositional factors on firm outcomes. Specifically, we analyze whether and how board composition affects the advancement and mobility of women CEOs and firm performance. Our analysis relies on a unique data set of all Chief Executive Officers (CEOs) and Board of Directors (BODs) in Fortune 500 companies over a ten-year period. We find a marginally significant positive relationship between board diversity and the likelihood of a woman being appointed CEO. We further find that board diversity significantly and positively influences the post-promotion success of women CEOs. Our findings suggest that board composition is critical for the appointment and success of women CEOs, and increasing board diversity should be central to any organizational diversity efforts. PMID:26188443

  12. Cooperative Antibiotic Resistance in a Multi-Drug Environment

    NASA Astrophysics Data System (ADS)

    Yurtsev, Eugene; Dai, Lei; Gore, Jeff

    2013-03-01

    The emergence of antibiotic resistance in bacteria is a significant health concern. A frequent mechanism of antibiotic resistance involves the production of an enzyme which inactivates the antibiotic. By inactivating the antibiotic, resistant cells can ``share'' their resistance with other cells in the bacterial population, suggesting that it may be possible to observe cooperation between strains that inactivate different antibiotics. Here, we experimentally track the population dynamics of two E. coli strains in the presence of two different antibiotics. We find that together the strains are able to grow in antibiotic concentrations that inhibit growth of either of the strains individually. We observe that even when there is stable coexistence between the two strains, the population size of each strain can undergo large oscillations. We expect that our results will provide insight into the evolution of antibiotic resistance and the evolutionary origin of phenotypic diversity and cooperative behaviors.

  13. The evolutionary origin of cooperators and defectors.

    PubMed

    Doebeli, Michael; Hauert, Christoph; Killingback, Timothy

    2004-10-29

    Coexistence of cooperators and defectors is common in nature, yet the evolutionary origin of such social diversification is unclear. Many models have been studied on the basis of the assumption that benefits of cooperative acts only accrue to others. Here, we analyze the continuous snowdrift game, in which cooperative investments are costly but yield benefits to others as well as to the cooperator. Adaptive dynamics of investment levels often result in evolutionary diversification from initially uniform populations to a stable state in which cooperators making large investments coexist with defectors who invest very little. Thus, when individuals benefit from their own actions, large asymmetries in cooperative investments can evolve.

  14. Five Rules for the Evolution of Cooperation

    NASA Astrophysics Data System (ADS)

    Nowak, Martin A.

    2006-12-01

    Cooperation is needed for evolution to construct new levels of organization. Genomes, cells, multicellular organisms, social insects, and human society are all based on cooperation. Cooperation means that selfish replicators forgo some of their reproductive potential to help one another. But natural selection implies competition and therefore opposes cooperation unless a specific mechanism is at work. Here I discuss five mechanisms for the evolution of cooperation: kin selection, direct reciprocity, indirect reciprocity, network reciprocity, and group selection. For each mechanism, a simple rule is derived that specifies whether natural selection can lead to cooperation.

  15. Education Cooperation for Tangible Results.

    ERIC Educational Resources Information Center

    Ritzen, Jozef M.

    2003-01-01

    Describes how development cooperation can help achieve developmental education goals, noting the impact of education on cultural, social, and material prosperity in later life, and discussing how quality education is the gateway to participation in society and better wages. The article examines challenges to quality education in developing…

  16. Cooperative Education: Lessons from Japan.

    ERIC Educational Resources Information Center

    Baris-Sanders, Marcia

    1997-01-01

    By using group activities for learning, cooperative student effort for school events, and peer pressure for classroom discipline, Japanese teachers involve and empower their students. While American students feel that classrooms are teachers' sacred ground, Japanese students appropriate them as their rightful community. Instead of stressing…

  17. Building Relationships through Cooperative Learning

    ERIC Educational Resources Information Center

    Bullard, Julie; Bullock, Janis R.

    2004-01-01

    Based upon several years of team-teaching intensive early childhood education courses, the authors discuss their experiences of building teacher-learner relationships through cooperative and collaborative learning. After witnessing significant conflict occurring within groups over the years, the authors began to investigate, discuss and integrate…

  18. Cooperative Program (Educable Mentally Retarded).

    ERIC Educational Resources Information Center

    Mississippi State Dept. of Education, Jackson. Div. of Instruction.

    Designed for the educable mentally handicapped youth at the secondary level, the cooperative vocational rehabilitation-special education plan in Mississippi is presented. Objectives, activities, and materials are suggested in the areas of vocational training, arithmetic, language arts, social studies, health and safety, recreation, physical…

  19. Facilitating Inter-District Cooperation.

    ERIC Educational Resources Information Center

    Schmidt, Gene L.

    After an introductory section which points out that the responsibility of small and rural schools is to provide all children with a quality education, and that Boards of Education must decide what is best for all children in the community, the paper briefly describes 16 exemplary programs involving cooperation between school districts. The…

  20. Studying Japan: The Cooperative Way.

    ERIC Educational Resources Information Center

    Hilke, Eileen

    1990-01-01

    Designs an elementary level social studies unit with the focus on Japan. Provides sample units of cooperative learning group projects. Suggests integrating mathematics, language arts, economics, fine arts, and science. Lists resources for obtaining more information and materials about Japan. (NL)

  1. Transparency in Cooperative Online Education

    ERIC Educational Resources Information Center

    Dalsgaard, Christian; Paulsen, Morten Flate

    2009-01-01

    The purpose of this article is to discuss the following question: What is the potential of social networking within cooperative online education? Social networking does not necessarily involve communication, dialogue, or collaboration. Instead, the authors argue that "transparency" is a unique feature of social networking services. Transparency…

  2. The Rhetorical Arts of Cooperation

    ERIC Educational Resources Information Center

    Fahnestock, Jeanne

    2013-01-01

    Human social evolution depends in part on using language persuasively to secure cooperation. Rhetoric emerged in the West over two thousand years ago as a deliberate cultural construction. Though often misunderstood today, rhetoric is fundamental in general education programs that teach students how knowledge is forged in agreement and applied.…

  3. Competitive Cooperation: The Iceberg Profile.

    ERIC Educational Resources Information Center

    Vaughan, Jerry L.

    Competitive athletes' scores on the Profile of Mood States (POMS) test create an iceberg-like pattern known as the "Iceberg Profile." Their scores for tension, depression, anger, fatigue, and confusion are low while their scores on vigor juts upward creating the "Iceberg Profile." Persons in a cooperative relationship are often competing against…

  4. What Makes Cooperative Learning Work.

    ERIC Educational Resources Information Center

    Johnson, David W.; Johnson, Roger T.

    This paper gives an introduction to cooperative learning (CL), providing a definition of what it is and is not (pseudo-learning groups, traditional classroom learning groups), discussing basic principles, describing two basic types of CL (formal and informal), and listing the benefits of CL suggested by previous research. In order to understand…

  5. Cooper, Labov, Larry and Charles.

    ERIC Educational Resources Information Center

    Winch, Christopher

    1985-01-01

    Research by Labov dealing with everyday speech and its relation to thinking and reasoning is critiqued, and Cooper's detailed criticism of Labov's research is discussed. Researchers should pay attention to actual speech in settings that are natural, rather than using only quantitative abstractions from artificial and restricted verbal encounters.…

  6. Marketing Cooperative Education. A Workshop.

    ERIC Educational Resources Information Center

    Mosser, John W.; Rea, Peter J.

    This document is a guide for a workshop on marketing college cooperative education programs. The guide takes the reader/workshop participant through the marketing process, from defining needs and resources to planning a marketing campaign, implementing it, and evaluating its success. Samples and sources also are provided. Topics covered in the…

  7. Astronaut Gordon Cooper After Recovery

    NASA Technical Reports Server (NTRS)

    1963-01-01

    Astronaut Gordon Cooper leaves the Faith 7 (MA-9) spacecraft after a successful recovery operation. The MA-9 mission, the last flight of the Mercury Project, was launched on May 15, 1963, orbited the Earth 22 times, and lasted for 1-1/2 days.

  8. Interlibrary Cooperation and Resource Sharing.

    ERIC Educational Resources Information Center

    Kittel, Dorothy

    Based on fiscal year 1986 annual reports from 48 states, Guam, Puerto Rico, and the Virgin Islands, this report describes interlibrary cooperation and resource sharing activities supported by the Library Services and Construction Act (LSCA), Title III, funds. In response to the 1984 amendment to Title III (which required each state to include in…

  9. Interlibrary Cooperation and Resource Sharing.

    ERIC Educational Resources Information Center

    Kittel, Dorothy

    Based on fiscal year 1985 annual reports from 48 states, this report describes interlibrary cooperation and resource-sharing activities supported by Library Services and Construction Act (LSCA), Title III, funds during 1985. A summary of types of activities reported includes the establishment, maintenance, and expansion of communication networks…

  10. Ability Grouping and Cooperative Learning.

    ERIC Educational Resources Information Center

    1994

    This collection of articles is intended to demonstrate that there is solid research to justify both ability grouping and cooperative learning with gifted students and that each approach should be used judiciously to address particular student needs. Introductory material describes the philosophy and program policy of the Center for Talented Youth…

  11. Invitational Education at Cooper Elementary

    ERIC Educational Resources Information Center

    Kalec, Ann W.

    2004-01-01

    In the summer of 1998, this author was appointed Principal at Cooper Elementary, one of 21 elementary schools in the Livonia Public Schools' district, the 5th largest district in the state of Michigan. Like many first-year principals, she was full of fresh ideas, lofty goals and endless enthusiasm to inspire students, staff and parents. Her…

  12. Evolution of cooperation without reciprocity

    NASA Astrophysics Data System (ADS)

    Riolo, Rick L.; Cohen, Michael D.; Axelrod, Robert

    2001-11-01

    A long-standing problem in biological and social sciences is to understand the conditions required for the emergence and maintenance of cooperation in evolving populations. For many situations, kin selection is an adequate explanation, although kin-recognition may still be a problem. Explanations of cooperation between non-kin include continuing interactions that provide a shadow of the future (that is, the expectation of an ongoing relationship) that can sustain reciprocity, possibly supported by mechanisms to bias interactions such as embedding the agents in a two-dimensional space or other context-preserving networks. Another explanation, indirect reciprocity, applies when benevolence to one agent increases the chance of receiving help from others. Here we use computer simulations to show that cooperation can arise when agents donate to others who are sufficiently similar to themselves in some arbitrary characteristic. Such a characteristic, or `tag', can be a marking, display, or other observable trait. Tag-based donation can lead to the emergence of cooperation among agents who have only rudimentary ability to detect environmental signals and, unlike models of direct or indirect reciprocity, no memory of past encounters is required.

  13. Creating and Sustaining Interfaith Cooperation on Christian Campuses: Tools and Challenges

    ERIC Educational Resources Information Center

    Basham, Katie; Hughes, Megan

    2012-01-01

    How can Christian colleges and universities promote interfaith cooperation on their campuses while remaining true to their particular theological orientations? The authors explore why Christian colleges are uniquely situated to positively engage religious diversity and offer best practices for interfaith work in a Christian college context from…

  14. Realizing Conflict, Negotiation, and Cooperation Concepts in the Context of International Water Courses

    ERIC Educational Resources Information Center

    Dinar, Ariel; McKinney, Daene

    2010-01-01

    In this paper we offer a negotiation and cooperative game theory application to international water in the classroom. A simulation game was developed for the Aral Sea water dispute as part of a textbook prepared for teaching a diverse group of students a graduate-level International Water course. A condensed version of the Aral Sea Basin water…

  15. High School Economics, Cooperative Learning, and the End-of-Course-Test--A Case Study

    ERIC Educational Resources Information Center

    Beavers, Sharon

    2011-01-01

    The primary purpose of this twelve-week case study was to explore the use of a cooperative learning strategy with small groups of students in a 12th-grade economics class as diverse learners prepared for tests. The complete case study was based on observations of students, student surveys, focus group interviews, and interviews with educators at…

  16. Thoughts on the International Cooperation and Exchanges of Chinese Research Universities

    ERIC Educational Resources Information Center

    Lu, Jiang-bin

    2009-01-01

    More prominent in the 21st century than ever are the internationalization of the competition for talents, the globalization of their mobility, and the diversity of the demand for them. This article analyzes the major features and content of the international cooperation and exchanges, and further discusses their tactics and measures in the process…

  17. Theoretical Framework for Cooperative Participatory Action Research (CPAR) in a Multicultural Campus: The Social Drama Model

    ERIC Educational Resources Information Center

    Hertz-Lazarowitz, Rachel; Zelniker, Tamar; Azaiza, Faisal

    2010-01-01

    This paper describes a long-term research seminar, developed in 2001 by Hertz-Lazarowitz at the University of Haifa (UH). The goal of the seminar was to involve students in a meaningful, experiential and cooperative-interactive learning environment, based on topics relevant to their development as individuals coming from diverse collectives to the…

  18. Unity in Diversity.

    ERIC Educational Resources Information Center

    Purves, Alan C.

    The cultural diversities of peoples and dialects in the United States have brought a richness to the English language that has made it one of the most supple of all the languages in the world. In addition to the diversity in the language are the diversities in literature, technology, nationality, politics, and styles of teaching. Teachers of…

  19. Multilevel and Diverse Classrooms

    ERIC Educational Resources Information Center

    Baurain, Bradley, Ed.; Ha, Phan Le, Ed.

    2010-01-01

    The benefits and advantages of classroom practices incorporating unity-in-diversity and diversity-in-unity are what "Multilevel and Diverse Classrooms" is all about. Multilevel classrooms--also known as mixed-ability or heterogeneous classrooms--are a fact of life in ESOL programs around the world. These classrooms are often not only multilevel…

  20. Leadership and Diversity

    ERIC Educational Resources Information Center

    Coleman, Marianne

    2012-01-01

    As part of the special edition recognizing the 40th anniversary of "Educational Management Administration & Leadership" this article reviews the coverage of leadership and diversity issues in the journal. The majority of articles concerning diversity have focused on gender, with attention turning to the wider concept of diversity since the year…

  1. Managing Generational Diversity

    ERIC Educational Resources Information Center

    O'Donovan, Eamonn

    2009-01-01

    Many school leaders have explored the issue of diversity when it comes to students, teachers and staff. Their focus typically has been on gender and ethnicity. However, generational diversity, an area of diversity that warrants serious consideration, has received less attention. Generational intelligence is important today for two reasons. First…

  2. Insights on Diversity.

    ERIC Educational Resources Information Center

    Bloom, Carol, Ed.; And Others

    This state-of-the-art report presents a series of essays on the topic of diversity. Essays include: (1) "Committing to Diversity" (George L. Mehaffy); (2) "Serving the Community by Serving Our Members" (Michael P. Wolfe); (3) "How Diversity Matters" (Asa G. Hilliard, III); (4) "A Prerequisite to Teaching Multiculturally" (Mary Louise Gomez); (5)…

  3. BioDiversity.

    ERIC Educational Resources Information Center

    Wilson, E. O., Ed.; Peter, Frances M., Ed.

    The diversity of life forms is one of the greatest wonders of the planet earth. The biosphere is an intricate tapestry of interwoven life forms. This book offers an overall view of this biological diversity and carries an urgent warning about the rapid alteration and destruction of the environments that have fostered the diversity of life forms…

  4. Promotion of cooperation induced by nonuniform payoff allocation in spatial public goods game

    NASA Astrophysics Data System (ADS)

    Peng, D.; Yang, H.-X.; Wang, W.-X.; Chen, G. R.; Wang, B.-H.

    2010-02-01

    A nonuniform payoff allocation mechanism is proposed for spatial public goods games where individuals are nodes on a scale-free network. Each individual is assigned a weight ki α, where ki is the degree of individual i and α is an adjustable parameter that controls the degree of diversity in individuals’ profits. During the evolution progress, the allocation of payoff on individual i is assumed to be proportional to its weight. Individuals synchronously update their strategies according to the stochastic rule with a fixed noise level. It is found that there exists an optimal value of α which yields the highest level of cooperation. Other pertinent quantities, including the payoff and the probability of finding a node playing as cooperator versus the degree, are also investigated computationally and analytically. Our results suggest that a suitable degree of diversity among individuals can promote the emergence of cooperation.

  5. Defectors Can Create Conditions That Rescue Cooperation

    PubMed Central

    Waite, Adam James; Cannistra, Caroline; Shou, Wenying

    2015-01-01

    Cooperation based on the production of costly common goods is observed throughout nature. This is puzzling, as cooperation is vulnerable to exploitation by defectors which enjoy a fitness advantage by consuming the common good without contributing fairly. Depletion of the common good can lead to population collapse and the destruction of cooperation. However, population collapse implies small population size, which, in a structured population, is known to favor cooperation. This happens because small population size increases variability in cooperator frequency across different locations. Since individuals in cooperator-dominated locations (which are most likely cooperators) will grow more than those in defector-dominated locations (which are most likely defectors), cooperators can outgrow defectors globally despite defectors outgrowing cooperators in each location. This raises the possibility that defectors can lead to conditions that sometimes rescue cooperation from defector-induced destruction. We demonstrate multiple mechanisms through which this can occur, using an individual-based approach to model stochastic birth, death, migration, and mutation events. First, during defector-induced population collapse, defectors occasionally go extinct before cooperators by chance, which allows cooperators to grow. Second, empty locations, either preexisting or created by defector-induced population extinction, can favor cooperation because they allow cooperator but not defector migrants to grow. These factors lead to the counterintuitive result that the initial presence of defectors sometimes allows better survival of cooperation compared to when defectors are initially absent. Finally, we find that resource limitation, inducible by defectors, can select for mutations adaptive to resource limitation. When these mutations are initially present at low levels or continuously generated at a moderate rate, they can favor cooperation by further reducing local population size

  6. The evolution of cooperation in asymmetric systems.

    PubMed

    Wang, RuiWu; Shi, Lei

    2010-01-01

    Explaining "Tragedy of the Commons" of evolution of cooperation remains one of the greatest problems for both biology and social science. Asymmetrical interaction, which is one of the most important characteristics of cooperative system, has not been sufficiently considered in the existing models of the evolution of cooperation. Considering the inequality in the number and payoff between the cooperative actors and recipients in cooperation systems, discriminative density-dependent interference competition will occur in limited dispersal systems. Our model and simulation show that the local but not the global stability of a cooperative interaction can be maintained if the utilization of common resource remains unsaturated, which can be achieved by density-dependent restraint or competition among the cooperative actors. More intense density dependent interference competition among the cooperative actors and the ready availability of the common resource, with a higher intrinsic contribution ratio of a cooperative actor to the recipient, will increase the probability of cooperation. The cooperation between the recipient and the cooperative actors can be transformed into conflict and, it oscillates chaotically with variations of the affecting factors under different environmental or ecological conditions. The higher initial relatedness (i.e. similar to kin or reciprocity relatedness), which is equivalent to intrinsic contribution ratio of a cooperative actor to the recipient, can be selected for by penalizing less cooperative or cheating actors but rewarding cooperative individuals in asymmetric systems. The initial relatedness is a pivot but not the aim of evolution of cooperation. This explains well the direct conflict observed in almost all cooperative systems.

  7. Work group diversity.

    PubMed

    van Knippenberg, Daan; Schippers, Michaéla C

    2007-01-01

    Work group diversity, the degree to which there are differences between group members, may affect group process and performance positively as well as negatively. Much is still unclear about the effects of diversity, however. We review the 1997-2005 literature on work group diversity to assess the state of the art and to identify key issues for future research. This review points to the need for more complex conceptualizations of diversity, as well as to the need for more empirical attention to the processes that are assumed to underlie the effects of diversity on group process and performance and to the contingency factors of these processes.

  8. Work group diversity.

    PubMed

    van Knippenberg, Daan; Schippers, Michaéla C

    2007-01-01

    Work group diversity, the degree to which there are differences between group members, may affect group process and performance positively as well as negatively. Much is still unclear about the effects of diversity, however. We review the 1997-2005 literature on work group diversity to assess the state of the art and to identify key issues for future research. This review points to the need for more complex conceptualizations of diversity, as well as to the need for more empirical attention to the processes that are assumed to underlie the effects of diversity on group process and performance and to the contingency factors of these processes. PMID:16903805

  9. Helping solve Georgia's water problems - the USGS Cooperative Water Program

    USGS Publications Warehouse

    Clarke, John S.

    2006-01-01

    The U.S. Geological Survey (USGS) addresses a wide variety of water issues in the State of Georgia through the Cooperative Water Program (CWP). As the primary Federal science agency for water-resource information, the USGS monitors the quantity and quality of water in the Nation's rivers and aquifers, assesses the sources and fate of contaminants in aquatic systems, collects and analyzes data on aquatic ecosystems, develops tools to improve the application of hydrologic information, and ensures that its information and tools are available to all potential users. This broad, diverse mission cannot be accomplished effectively without the contributions of the CWP.

  10. From quorum to cooperation: lessons from bacterial sociality for evolutionary theory.

    PubMed

    Lyon, Pamela

    2007-12-01

    The study of cooperation and altruism, almost since its inception, has been carried out without reference to the most numerous, diverse and very possibly most cooperative domain of life on the planet: bacteria. This is starting to change, for good reason. Far from being clonal loners, bacteria are highly social creatures capable of astonishingly complex collective behaviour that is mediated, as it is in colonial insects, by chemical communication. The article discusses recent experiments that explore different facets of current theories of the evolution and maintenance of cooperation using bacterial models. Not only do bacteria hold great promise as experimentally tractable, rapidly evolving systems for testing hypotheses, bacterial experiments have already raised interesting questions about the assumptions on which our current understanding of cooperation and altruism rests.

  11. Cooperation between distinct viral variants promotes growth of H3N2 influenza in cell culture.

    PubMed

    Xue, Katherine S; Hooper, Kathryn A; Ollodart, Anja R; Dingens, Adam S; Bloom, Jesse D

    2016-01-01

    RNA viruses rapidly diversify into quasispecies of related genotypes. This genetic diversity has long been known to facilitate adaptation, but recent studies have suggested that cooperation between variants might also increase population fitness. Here, we demonstrate strong cooperation between two H3N2 influenza variants that differ by a single mutation at residue 151 in neuraminidase, which normally mediates viral exit from host cells. Residue 151 is often annotated as an ambiguous amino acid in sequenced isolates, indicating mixed viral populations. We show that mixed populations grow better than either variant alone in cell culture. Pure populations of either variant generate the other through mutation and then stably maintain a mix of the two genotypes. We suggest that cooperation arises because mixed populations combine one variant's proficiency at cell entry with the other's proficiency at cell exit. Our work demonstrates a specific cooperative interaction between defined variants in a viral quasispecies. PMID:26978794

  12. Cooperative Planning in Action: The Washington Experiment

    ERIC Educational Resources Information Center

    Gell, Marilyn

    1976-01-01

    Library cooperation in the Metropolitan Washington area is described, along with its problems and successes, and the significant role special libraries can play in an ambitious intertype library cooperative. (Author/PF)

  13. The virtual cooperation platform in enterprise and supplier cooperation models.

    PubMed

    Chang, Che-Wei; Wu, Cheng-Ru; Liao, Chia-Chun

    2010-08-01

    Abstract This study examines the use of the virtual enterprise network supplier supply-chain model of business behavior in creating synergies of cooperation. To explore virtual network behavior, it evaluates 60 samples, taken from of a few supply chains, and 17 items meeting certain behavioral criteria. Such an analysis may help to reduce costs and processing time effectively, as well as promote effective communication. Furthermore, the study of behavior in this electronic setting is a reliable and useful assessment method. PMID:20649447

  14. Collective cell guidance by cooperative intercellular forces

    PubMed Central

    Tambe, Dhananjay T.; Hardin, C. Corey; Angelini, Thomas E.; Rajendran, Kavitha; Park, Chan Young; Serra-Picamal, Xavier; Zhou, Enhua H.; Zaman, Muhammad H.; Butler, James P.; Weitz, David A.; Fredberg, Jeffrey J.; Trepat, Xavier

    2011-01-01

    Cells comprising a tissue migrate as part of a collective. How collective processes are coordinated over large multi-cellular assemblies has remained unclear, however, because mechanical stresses exerted at cell-cell junctions have not been accessible experimentally. We report here maps of these stresses within and between cells comprising a monolayer. Within the cell sheet there arise unanticipated fluctuations of mechanical stress that are severe, emerge spontaneously, and ripple across the monolayer. This stress landscape becomes increasingly rugged, sluggish, and cooperative with increasing system density. Within that landscape, local cellular migrations follow local orientations of maximal principal stress. Migrations of both endothelial and epithelial monolayers conform to this behavior, as do breast cancer cell lines before but not after the epithelial-mesenchymal transition. Collective migration in these diverse systems is seen to be governed by a simple but unifying physiological principle: neighboring cells join forces to transmit appreciable normal stress across the cell-cell junction, but migrate along orientations of minimal intercellular shear stress. PMID:21602808

  15. 34 CFR 84.620 - Cooperative agreement.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 34 Education 1 2010-07-01 2010-07-01 false Cooperative agreement. 84.620 Section 84.620 Education Office of the Secretary, Department of Education GOVERNMENTWIDE REQUIREMENTS FOR DRUG-FREE WORKPLACE (FINANCIAL ASSISTANCE) Definitions § 84.620 Cooperative agreement. Cooperative agreement means an award...

  16. 40 CFR 1501.6 - Cooperating agencies.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 33 2011-07-01 2011-07-01 false Cooperating agencies. 1501.6 Section 1501.6 Protection of Environment COUNCIL ON ENVIRONMENTAL QUALITY NEPA AND AGENCY PLANNING § 1501.6 Cooperating agencies. The purpose of this section is to emphasize agency cooperation early in the NEPA...

  17. 49 CFR 11.114 - Cooperative research.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false Cooperative research. 11.114 Section 11.114... research. Cooperative research projects are those projects covered by this policy which involve more than one institution. In the conduct of cooperative research projects, each institution is responsible...

  18. 22 CFR 225.114 - Cooperative research.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Cooperative research. 225.114 Section 225.114... research. Cooperative research projects are those projects covered by this policy which involve more than one institution. In the conduct of cooperative research projects, each institution is responsible...

  19. 34 CFR 97.114 - Cooperative research.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 34 Education 1 2010-07-01 2010-07-01 false Cooperative research. 97.114 Section 97.114 Education... Protection of Human Subjects (Basic ED Policy for Protection of Human Research Subjects) § 97.114 Cooperative research. Cooperative research projects are those projects covered by this policy which involve more...

  20. 7 CFR 1c.114 - Cooperative research.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 1 2010-01-01 2010-01-01 false Cooperative research. 1c.114 Section 1c.114 Agriculture Office of the Secretary of Agriculture PROTECTION OF HUMAN SUBJECTS § 1c.114 Cooperative research. Cooperative research projects are those projects covered by this policy which involve more than...

  1. 22 CFR 225.114 - Cooperative research.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 22 Foreign Relations 1 2014-04-01 2014-04-01 false Cooperative research. 225.114 Section 225.114... research. Cooperative research projects are those projects covered by this policy which involve more than one institution. In the conduct of cooperative research projects, each institution is responsible...

  2. 45 CFR 46.114 - Cooperative research.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 45 Public Welfare 1 2012-10-01 2012-10-01 false Cooperative research. 46.114 Section 46.114 Public... HHS Policy for Protection of Human Research Subjects § 46.114 Cooperative research. Cooperative research projects are those projects covered by this policy which involve more than one institution. In...

  3. 49 CFR 11.114 - Cooperative research.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 1 2013-10-01 2013-10-01 false Cooperative research. 11.114 Section 11.114... research. Cooperative research projects are those projects covered by this policy which involve more than one institution. In the conduct of cooperative research projects, each institution is responsible...

  4. 49 CFR 11.114 - Cooperative research.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 1 2014-10-01 2014-10-01 false Cooperative research. 11.114 Section 11.114... research. Cooperative research projects are those projects covered by this policy which involve more than one institution. In the conduct of cooperative research projects, each institution is responsible...

  5. 22 CFR 225.114 - Cooperative research.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 22 Foreign Relations 1 2012-04-01 2012-04-01 false Cooperative research. 225.114 Section 225.114... research. Cooperative research projects are those projects covered by this policy which involve more than one institution. In the conduct of cooperative research projects, each institution is responsible...

  6. 40 CFR 26.114 - Cooperative research.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 1 2013-07-01 2013-07-01 false Cooperative research. 26.114 Section 26... Basic EPA Policy for Protection of Subjects in Human Research Conducted or Supported by EPA § 26.114 Cooperative research. Cooperative research projects are those projects covered by this policy which...

  7. 49 CFR 11.114 - Cooperative research.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 1 2012-10-01 2012-10-01 false Cooperative research. 11.114 Section 11.114... research. Cooperative research projects are those projects covered by this policy which involve more than one institution. In the conduct of cooperative research projects, each institution is responsible...

  8. 40 CFR 26.114 - Cooperative research.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 1 2012-07-01 2012-07-01 false Cooperative research. 26.114 Section 26... Basic EPA Policy for Protection of Subjects in Human Research Conducted or Supported by EPA § 26.114 Cooperative research. Cooperative research projects are those projects covered by this policy which...

  9. 34 CFR 97.114 - Cooperative research.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 34 Education 1 2012-07-01 2012-07-01 false Cooperative research. 97.114 Section 97.114 Education... Protection of Human Subjects (Basic ED Policy for Protection of Human Research Subjects) § 97.114 Cooperative research. Cooperative research projects are those projects covered by this policy which involve more...

  10. 7 CFR 1c.114 - Cooperative research.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 1 2013-01-01 2013-01-01 false Cooperative research. 1c.114 Section 1c.114 Agriculture Office of the Secretary of Agriculture PROTECTION OF HUMAN SUBJECTS § 1c.114 Cooperative research. Cooperative research projects are those projects covered by this policy which involve more than...

  11. 7 CFR 1c.114 - Cooperative research.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 1 2012-01-01 2012-01-01 false Cooperative research. 1c.114 Section 1c.114 Agriculture Office of the Secretary of Agriculture PROTECTION OF HUMAN SUBJECTS § 1c.114 Cooperative research. Cooperative research projects are those projects covered by this policy which involve more than...

  12. 34 CFR 97.114 - Cooperative research.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 34 Education 1 2014-07-01 2014-07-01 false Cooperative research. 97.114 Section 97.114 Education... Protection of Human Subjects (Basic ED Policy for Protection of Human Research Subjects) § 97.114 Cooperative research. Cooperative research projects are those projects covered by this policy which involve more...

  13. 45 CFR 46.114 - Cooperative research.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 45 Public Welfare 1 2013-10-01 2013-10-01 false Cooperative research. 46.114 Section 46.114 Public... HHS Policy for Protection of Human Research Subjects § 46.114 Cooperative research. Cooperative research projects are those projects covered by this policy which involve more than one institution. In...

  14. 34 CFR 97.114 - Cooperative research.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 34 Education 1 2013-07-01 2013-07-01 false Cooperative research. 97.114 Section 97.114 Education... Protection of Human Subjects (Basic ED Policy for Protection of Human Research Subjects) § 97.114 Cooperative research. Cooperative research projects are those projects covered by this policy which involve more...

  15. 22 CFR 225.114 - Cooperative research.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 22 Foreign Relations 1 2013-04-01 2013-04-01 false Cooperative research. 225.114 Section 225.114... research. Cooperative research projects are those projects covered by this policy which involve more than one institution. In the conduct of cooperative research projects, each institution is responsible...

  16. 7 CFR 1c.114 - Cooperative research.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 1 2014-01-01 2014-01-01 false Cooperative research. 1c.114 Section 1c.114 Agriculture Office of the Secretary of Agriculture PROTECTION OF HUMAN SUBJECTS § 1c.114 Cooperative research. Cooperative research projects are those projects covered by this policy which involve more than...

  17. 40 CFR 26.114 - Cooperative research.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 1 2014-07-01 2014-07-01 false Cooperative research. 26.114 Section 26... Basic EPA Policy for Protection of Subjects in Human Research Conducted or Supported by EPA § 26.114 Cooperative research. Cooperative research projects are those projects covered by this policy which...

  18. 45 CFR 46.114 - Cooperative research.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 45 Public Welfare 1 2014-10-01 2014-10-01 false Cooperative research. 46.114 Section 46.114 Public... HHS Policy for Protection of Human Research Subjects § 46.114 Cooperative research. Cooperative research projects are those projects covered by this policy which involve more than one institution. In...

  19. 14 CFR 1230.114 - Cooperative research.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 5 2011-01-01 2010-01-01 true Cooperative research. 1230.114 Section 1230.114 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION PROTECTION OF HUMAN SUBJECTS § 1230.114 Cooperative research. Cooperative research projects are those projects covered by this...

  20. 14 CFR 1230.114 - Cooperative research.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 5 2012-01-01 2012-01-01 false Cooperative research. 1230.114 Section 1230.114 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION PROTECTION OF HUMAN SUBJECTS § 1230.114 Cooperative research. Cooperative research projects are those projects covered by this...

  1. 14 CFR 1230.114 - Cooperative research.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 5 2013-01-01 2013-01-01 false Cooperative research. 1230.114 Section 1230.114 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION PROTECTION OF HUMAN SUBJECTS § 1230.114 Cooperative research. Cooperative research projects are those projects covered by this...

  2. Cooperative Learning and Outdoor/Environmental Education.

    ERIC Educational Resources Information Center

    Knapp, Clifford E., Ed.

    1986-01-01

    This newsletter contains 14 items on cooperative learning and outdoor education, with a particular focus on environmental education and ecology. "Cooperative Teaching/Learning Strategies and Objectives in Outdoor/Environmental Education" by Clifford E. Knapp is about cooperative teaching and learning strategies in outdoor education and emphasizes…

  3. 7 CFR 1c.114 - Cooperative research.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 1 2011-01-01 2011-01-01 false Cooperative research. 1c.114 Section 1c.114 Agriculture Office of the Secretary of Agriculture PROTECTION OF HUMAN SUBJECTS § 1c.114 Cooperative research. Cooperative research projects are those projects covered by this policy which involve more than...

  4. 34 CFR 97.114 - Cooperative research.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 34 Education 1 2011-07-01 2011-07-01 false Cooperative research. 97.114 Section 97.114 Education... Protection of Human Subjects (Basic ED Policy for Protection of Human Research Subjects) § 97.114 Cooperative research. Cooperative research projects are those projects covered by this policy which involve more...

  5. 22 CFR 225.114 - Cooperative research.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 22 Foreign Relations 1 2011-04-01 2011-04-01 false Cooperative research. 225.114 Section 225.114... research. Cooperative research projects are those projects covered by this policy which involve more than one institution. In the conduct of cooperative research projects, each institution is responsible...

  6. 49 CFR 11.114 - Cooperative research.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 1 2011-10-01 2011-10-01 false Cooperative research. 11.114 Section 11.114... research. Cooperative research projects are those projects covered by this policy which involve more than one institution. In the conduct of cooperative research projects, each institution is responsible...

  7. 7 CFR 1.76 - Department cooperation.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 1 2014-01-01 2014-01-01 false Department cooperation. 1.76 Section 1.76 Agriculture Office of the Secretary of Agriculture ADMINISTRATIVE REGULATIONS Cooperative Production of Television... Department will check and work with the cooperators to arrange shooting schedules in order to...

  8. 7 CFR 1.76 - Department cooperation.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 1 2013-01-01 2013-01-01 false Department cooperation. 1.76 Section 1.76 Agriculture Office of the Secretary of Agriculture ADMINISTRATIVE REGULATIONS Cooperative Production of Television... Department will check and work with the cooperators to arrange shooting schedules in order to...

  9. Preschool-Home Cooperation in Change

    ERIC Educational Resources Information Center

    Sandberg, Anette; Vuorinen, Tuula

    2008-01-01

    The purpose of this study is to bring forth preschool teachers' and parents' views on both established and future forms of cooperation between the preschool and home. The empirical sample is based on both individual and focus-group interviews. Results show that cooperation mainly revolves around the individual child. The form of cooperation that…

  10. 38 CFR 21.4151 - Cooperation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 2 2010-07-01 2010-07-01 false Cooperation. 21.4151... Agencies § 21.4151 Cooperation. (a) The Department of Veterans Affairs and the State approving agencies..., the cooperation of the Department of Veterans Affairs and the State approving agencies is...

  11. 15 CFR 922.187 - Interagency Cooperation.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 15 Commerce and Foreign Trade 3 2010-01-01 2010-01-01 false Interagency Cooperation. 922.187... Sanctuary § 922.187 Interagency Cooperation. Under section 304(d) of the NMSA, Federal agency actions... cooperation procedures required by other statutes, such as the ESA. The Director will attempt to...

  12. 20 CFR 616.3 - Interstate cooperation.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Interstate cooperation. 616.3 Section 616.3 Employees' Benefits EMPLOYMENT AND TRAINING ADMINISTRATION, DEPARTMENT OF LABOR INTERSTATE ARRANGEMENT FOR COMBINING EMPLOYMENT AND WAGES § 616.3 Interstate cooperation. Each State agency will cooperate with...

  13. Activities for Science: Cooperative Learning Lessons (Challenging).

    ERIC Educational Resources Information Center

    Jasmine, Grace; Jasmine, Julia

    This book is designed to help advanced elementary students learn science skills while actively engaged in cooperative activities based on the earth sciences and natural disasters. The first section explains how to make cooperative learning a part of the curriculum and includes an overview, instructions and activities to bring cooperative learning…

  14. Culture, Cooperation, and the General Welfare

    ERIC Educational Resources Information Center

    Berigan, Nick; Irwin, Kyle

    2011-01-01

    Solutions to social dilemmas require cooperation. Given that there are commonly multiple avenues for cooperation, sometimes social dilemmas require coordination of strategies in addition to sufficient cooperation to be successful. This study examines one social dilemma where such coordination is necessary: supporting the general welfare. Using…

  15. 10 CFR 607.620 - Cooperative agreement.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Cooperative agreement. 607.620 Section 607.620 Energy DEPARTMENT OF ENERGY (CONTINUED) ASSISTANCE REGULATIONS GOVERNMENTWIDE REQUIREMENTS FOR DRUG-FREE WORKPLACE (FINANCIAL ASSISTANCE) Definitions § 607.620 Cooperative agreement. Cooperative agreement means an award...

  16. 7 CFR 611.2 - Cooperative relationships.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ..., DEPARTMENT OF AGRICULTURE CONSERVATION OPERATIONS SOIL SURVEYS General § 611.2 Cooperative relationships. (a) Soil surveys on nonfederal lands are carried out cooperatively with State agricultural experiment... setting forth guidelines for actions to be taken by each cooperating party in the performance of...

  17. 7 CFR 611.2 - Cooperative relationships.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., DEPARTMENT OF AGRICULTURE CONSERVATION OPERATIONS SOIL SURVEYS General § 611.2 Cooperative relationships. (a) Soil surveys on nonfederal lands are carried out cooperatively with State agricultural experiment... setting forth guidelines for actions to be taken by each cooperating party in the performance of...

  18. 7 CFR 611.2 - Cooperative relationships.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ..., DEPARTMENT OF AGRICULTURE CONSERVATION OPERATIONS SOIL SURVEYS General § 611.2 Cooperative relationships. (a) Soil surveys on nonfederal lands are carried out cooperatively with State agricultural experiment... setting forth guidelines for actions to be taken by each cooperating party in the performance of...

  19. 7 CFR 611.2 - Cooperative relationships.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., DEPARTMENT OF AGRICULTURE CONSERVATION OPERATIONS SOIL SURVEYS General § 611.2 Cooperative relationships. (a) Soil surveys on nonfederal lands are carried out cooperatively with State agricultural experiment... setting forth guidelines for actions to be taken by each cooperating party in the performance of...

  20. 7 CFR 611.2 - Cooperative relationships.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ..., DEPARTMENT OF AGRICULTURE CONSERVATION OPERATIONS SOIL SURVEYS General § 611.2 Cooperative relationships. (a) Soil surveys on nonfederal lands are carried out cooperatively with State agricultural experiment... setting forth guidelines for actions to be taken by each cooperating party in the performance of...

  1. Keeping a Dream Alive: Cooper Union Library.

    ERIC Educational Resources Information Center

    Iwan, Irene

    1984-01-01

    Profiles the Cooper Union Library, a private academic library specializing in architecture, art, and engineering that celebrated its 125th anniversary in fall 1984. Highlights include a biographical sketch of the college's founder, Peter Cooper; construction of the building; curriculum changes; library services and materials; and cooperative and…

  2. 7 CFR 1.76 - Department cooperation.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 1 2012-01-01 2012-01-01 false Department cooperation. 1.76 Section 1.76 Agriculture Office of the Secretary of Agriculture ADMINISTRATIVE REGULATIONS Cooperative Production of Television Films § 1.76 Department cooperation. When the producer agrees to meet the above stipulations to...

  3. 45 CFR 690.114 - Cooperative research.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 45 Public Welfare 3 2011-10-01 2011-10-01 false Cooperative research. 690.114 Section 690.114 Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION PROTECTION OF HUMAN SUBJECTS § 690.114 Cooperative research. Cooperative research projects are those...

  4. Labor-Management Cooperation: The American Experience.

    ERIC Educational Resources Information Center

    Siegel, Irving H.; Weinberg, Edgar

    This book examines the wide range of opportunities, the attendant problems, and the potential benefits of labor-management cooperation. Cooperative arrangements are considered at different economic levels, and 65 cases are discussed. The first of 10 chapters sets up a conceptual framework for the review of American experience in cooperation.…

  5. 14 CFR 1230.114 - Cooperative research.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 5 2010-01-01 2010-01-01 false Cooperative research. 1230.114 Section 1230.114 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION PROTECTION OF HUMAN SUBJECTS § 1230.114 Cooperative research. Cooperative research projects are those projects covered by this...

  6. Cooperative Learning and Elementary Social Studies.

    ERIC Educational Resources Information Center

    Guyton, Edith

    1991-01-01

    Argues that cooperative learning is useful in elementary social studies instruction. Identifies positive interdependence, student interaction, individual accountability for mastering material, and appropriate interpersonal and small group skills as essential elements of cooperative learning. Suggests that cooperative learning can help teach social…

  7. Keys to Cooperative Education Programs. Volume I.

    ERIC Educational Resources Information Center

    National Child Labor Committee, New York, NY.

    This first volume of a two-volume manual provides a structure for the analysis of the design of cooperative education and the implementation of the design in terms of the 49 key elements of cooperative education. It is intended for use by persons responsible for cooperative education at state and local levels. Volume I contains the introduction…

  8. 1 CFR 8.7 - Agency cooperation.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 1 General Provisions 1 2013-01-01 2012-01-01 true Agency cooperation. 8.7 Section 8.7 General Provisions ADMINISTRATIVE COMMITTEE OF THE FEDERAL REGISTER SPECIAL EDITIONS OF THE FEDERAL REGISTER CODE OF FEDERAL REGULATIONS § 8.7 Agency cooperation. Each agency shall cooperate in keeping publication of...

  9. 1 CFR 8.7 - Agency cooperation.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 1 General Provisions 1 2012-01-01 2012-01-01 false Agency cooperation. 8.7 Section 8.7 General Provisions ADMINISTRATIVE COMMITTEE OF THE FEDERAL REGISTER SPECIAL EDITIONS OF THE FEDERAL REGISTER CODE OF FEDERAL REGULATIONS § 8.7 Agency cooperation. Each agency shall cooperate in keeping publication of...

  10. 1 CFR 8.7 - Agency cooperation.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 1 General Provisions 1 2014-01-01 2012-01-01 true Agency cooperation. 8.7 Section 8.7 General Provisions ADMINISTRATIVE COMMITTEE OF THE FEDERAL REGISTER SPECIAL EDITIONS OF THE FEDERAL REGISTER CODE OF FEDERAL REGULATIONS § 8.7 Agency cooperation. Each agency shall cooperate in keeping publication of...

  11. 40 CFR 26.114 - Cooperative research.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Basic EPA Policy for Protection of Subjects in Human Research Conducted or Supported by EPA § 26.114 Cooperative research. Cooperative research projects are those projects covered by this policy which involve... 40 Protection of Environment 1 2011-07-01 2011-07-01 false Cooperative research. 26.114 Section...

  12. 40 CFR 26.114 - Cooperative research.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Basic EPA Policy for Protection of Subjects in Human Research Conducted or Supported by EPA § 26.114 Cooperative research. Cooperative research projects are those projects covered by this policy which involve... 40 Protection of Environment 1 2010-07-01 2010-07-01 false Cooperative research. 26.114 Section...

  13. 42 CFR 411.23 - Beneficiary's cooperation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 2 2010-10-01 2010-10-01 false Beneficiary's cooperation. 411.23 Section 411.23... Medicare Payment: General Provisions § 411.23 Beneficiary's cooperation. (a) If CMS takes action to recover conditional payments, the beneficiary must cooperate in the action. (b) If CMS's recovery action...

  14. 76 FR 34692 - Inside Passage Electric Cooperative

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-14

    ... Energy Regulatory Commission Inside Passage Electric Cooperative Notice of Preliminary Permit Application..., 2011, and supplemented on May 18, 2011, the Inside Passage Electric Cooperative filed an application.... Applicant Contact: Mr. Peter A. Bibb, Operations Manager, Inside Passage Electric Cooperative, P.O....

  15. Report: National Conference on Cooperative Education.

    ERIC Educational Resources Information Center

    Bureau of Occupational and Adult Education (DHEW/OE), Washington, DC. Div. of Vocational and Technical Education.

    The conference report on cooperative vocational education contains four main sections. The first, background papers, contains three papers: Education in a Changing Society, Carl H. Madden; A Prospectus for Cooperative Vocational Education, William F. Pierce; and Critical Issues in Cooperative Vocational Education, Robert M. Worthington. The second…

  16. Co-Operative Language Learning: What's News?

    ERIC Educational Resources Information Center

    Rodgers, Ted

    This discussion of cooperative second language learning describes the approach in terms of response to three questions: WHO? WHAT? and WHY? The first section "WHO: Major Directors and Actors," chronicles the evolution of cooperative learning in general and cooperative language learning in particular, citing some specific methods and the…

  17. Cooperation in defence against a predator.

    PubMed

    Garay, József

    2009-03-01

    The origin and the evolutionary stability of cooperation between unrelated individuals is one of the key problems of evolutionary biology. In this paper, a cooperative defence game against a predator is introduced which is based on Hamilton's selfish herd theory and Eshel's survival game models. Cooperation is altruistic in the sense that the individual, which is not the target of the predator, helps the members of the group attacked by the predator and during defensive action the helper individual may also die in any attack. In order to decrease the long term predation risk, this individual has to carry out a high risk action. Here I show that this kind of cooperative behaviour can evolve in small groups. The reason for the emergence of cooperation is that if the predator does not kill a mate of a cooperative individual, then the survival probability of the cooperative individual will increase in two cases. If the mate is non-cooperative, then-according to the dilution effect, the predator confusion effect and the higher predator vigilance-the survival probability of the cooperative individual increases. The second case is when the mate is cooperative, because a cooperative individual has a further gain, the active help in defence during further predator attacks. Thus, if an individual can increase the survival rate of its mates (no matter whether the mate is cooperative or not), then its own predation risk will decrease.

  18. 28 CFR 83.620 - Cooperative agreement.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Cooperative agreement. 83.620 Section 83.620 Judicial Administration DEPARTMENT OF JUSTICE (CONTINUED) GOVERNMENT-WIDE REQUIREMENTS FOR DRUG-FREE WORKPLACE (GRANTS) Definitions § 83.620 Cooperative agreement. Cooperative agreement means...

  19. 7 CFR 1220.107 - Cooperator organization.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 10 2013-01-01 2013-01-01 false Cooperator organization. 1220.107 Section 1220.107... CONSUMER INFORMATION Soybean Promotion and Research Order Definitions § 1220.107 Cooperator organization. The term Cooperator Organization means the American Soybean Association, or any successor...

  20. 7 CFR 1220.107 - Cooperator organization.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 10 2012-01-01 2012-01-01 false Cooperator organization. 1220.107 Section 1220.107... CONSUMER INFORMATION Soybean Promotion and Research Order Definitions § 1220.107 Cooperator organization. The term Cooperator Organization means the American Soybean Association, or any successor...

  1. 7 CFR 1220.107 - Cooperator organization.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 10 2014-01-01 2014-01-01 false Cooperator organization. 1220.107 Section 1220.107... CONSUMER INFORMATION Soybean Promotion and Research Order Definitions § 1220.107 Cooperator organization. The term Cooperator Organization means the American Soybean Association, or any successor...

  2. 7 CFR 1220.107 - Cooperator organization.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Cooperator organization. 1220.107 Section 1220.107... CONSUMER INFORMATION Soybean Promotion and Research Order Definitions § 1220.107 Cooperator organization. The term Cooperator Organization means the American Soybean Association, or any successor...

  3. 7 CFR 1220.107 - Cooperator organization.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 10 2011-01-01 2011-01-01 false Cooperator organization. 1220.107 Section 1220.107... CONSUMER INFORMATION Soybean Promotion and Research Order Definitions § 1220.107 Cooperator organization. The term Cooperator Organization means the American Soybean Association, or any successor...

  4. 7 CFR 1.76 - Department cooperation.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 1 2010-01-01 2010-01-01 false Department cooperation. 1.76 Section 1.76 Agriculture Office of the Secretary of Agriculture ADMINISTRATIVE REGULATIONS Cooperative Production of Television Films § 1.76 Department cooperation. When the producer agrees to meet the above stipulations to...

  5. 42 CFR 411.23 - Beneficiary's cooperation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 2 2011-10-01 2011-10-01 false Beneficiary's cooperation. 411.23 Section 411.23... Medicare Payment: General Provisions § 411.23 Beneficiary's cooperation. (a) If CMS takes action to recover conditional payments, the beneficiary must cooperate in the action. (b) If CMS's recovery action...

  6. 7 CFR 1.76 - Department cooperation.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 1 2011-01-01 2011-01-01 false Department cooperation. 1.76 Section 1.76 Agriculture Office of the Secretary of Agriculture ADMINISTRATIVE REGULATIONS Cooperative Production of Television Films § 1.76 Department cooperation. When the producer agrees to meet the above stipulations to...

  7. 1 CFR 8.7 - Agency cooperation.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 1 General Provisions 1 2011-01-01 2011-01-01 false Agency cooperation. 8.7 Section 8.7 General Provisions ADMINISTRATIVE COMMITTEE OF THE FEDERAL REGISTER SPECIAL EDITIONS OF THE FEDERAL REGISTER CODE OF FEDERAL REGULATIONS § 8.7 Agency cooperation. Each agency shall cooperate in keeping publication of...

  8. 1 CFR 8.7 - Agency cooperation.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 1 General Provisions 1 2010-01-01 2010-01-01 false Agency cooperation. 8.7 Section 8.7 General Provisions ADMINISTRATIVE COMMITTEE OF THE FEDERAL REGISTER SPECIAL EDITIONS OF THE FEDERAL REGISTER CODE OF FEDERAL REGULATIONS § 8.7 Agency cooperation. Each agency shall cooperate in keeping publication of...

  9. 29 CFR 1607.8 - Cooperative studies.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 4 2014-07-01 2014-07-01 false Cooperative studies. 1607.8 Section 1607.8 Labor... EMPLOYEE SELECTION PROCEDURES (1978) General Principles § 1607.8 Cooperative studies. A. Encouragement of cooperative studies. The agencies issuing these guidelines encourage employers, labor organizations,...

  10. 29 CFR 1607.8 - Cooperative studies.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 4 2010-07-01 2010-07-01 false Cooperative studies. 1607.8 Section 1607.8 Labor... EMPLOYEE SELECTION PROCEDURES (1978) General Principles § 1607.8 Cooperative studies. A. Encouragement of cooperative studies. The agencies issuing these guidelines encourage employers, labor organizations,...

  11. 29 CFR 1607.8 - Cooperative studies.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 4 2011-07-01 2011-07-01 false Cooperative studies. 1607.8 Section 1607.8 Labor... EMPLOYEE SELECTION PROCEDURES (1978) General Principles § 1607.8 Cooperative studies. A. Encouragement of cooperative studies. The agencies issuing these guidelines encourage employers, labor organizations,...

  12. 29 CFR 1607.8 - Cooperative studies.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 4 2012-07-01 2012-07-01 false Cooperative studies. 1607.8 Section 1607.8 Labor... EMPLOYEE SELECTION PROCEDURES (1978) General Principles § 1607.8 Cooperative studies. A. Encouragement of cooperative studies. The agencies issuing these guidelines encourage employers, labor organizations,...

  13. 29 CFR 1607.8 - Cooperative studies.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 4 2013-07-01 2013-07-01 false Cooperative studies. 1607.8 Section 1607.8 Labor... EMPLOYEE SELECTION PROCEDURES (1978) General Principles § 1607.8 Cooperative studies. A. Encouragement of cooperative studies. The agencies issuing these guidelines encourage employers, labor organizations,...

  14. Cooperative Game Theoretic Models for Decision-Making in Contexts of Library Cooperation.

    ERIC Educational Resources Information Center

    Hayes, Robert M.

    2003-01-01

    Presents a brief summary of Cooperative Economic Game Theory, followed by a summary of specific measures identified by Nash, Shapley, and Harsanyi. Reviews contexts in which negotiation and cooperation among libraries is of special economic importance, and for two of these contexts-cooperative acquisitions and cooperative automation-illustrates…

  15. Brain theory and cooperative computation.

    PubMed

    Arbib, M A

    1985-01-01

    "Top-down" brain theory, based upon functional analysis of cognitive processes in terms of interacting schemas, is distinguished from "bottom-up" brain theory based on analysis of the dynamics of neural nets. "Cooperative computation" is proposed as the style of interaction of neural subsystems at various levels. Perceptual schemas are introduced as the building blocks for the representation of the perceived environment, and motor schemas serve as control systems to be coordinated into programs for the control of movement. A cooperative computation view of the design of machine vision systems is exemplified both by an algorithm for computing optic flow which offers interesting insights into the evolution of hierarchical neural structures, and by an analysis of knowledge representation for machine interpretation of visual scenes. The interaction between top-down analysis and detailed neural modelling is illustrated by the study of visuomotor coordination in frogs and toads.

  16. Cooperative epidemics on multiplex networks

    NASA Astrophysics Data System (ADS)

    Azimi-Tafreshi, N.

    2016-04-01

    The spread of one disease, in some cases, can stimulate the spreading of another infectious disease. Here, we treat analytically a symmetric coinfection model for spreading of two diseases on a two-layer multiplex network. We allow layer overlapping, but we assume that each layer is random and locally loopless. Infection with one of the diseases increases the probability of getting infected with the other. Using the generating function method, we calculate exactly the fraction of individuals infected with both diseases (so-called coinfected clusters) in the stationary state, as well as the epidemic spreading thresholds and the phase diagram of the model. With increasing cooperation, we observe a tricritical point and the type of transition changes from continuous to hybrid. Finally, we compare the coinfected clusters in the case of cooperating diseases with the so-called "viable" clusters in networks with dependencies.

  17. Flux Quantization Without Cooper Pairs

    NASA Astrophysics Data System (ADS)

    Kadin, Alan

    2013-03-01

    It is universally accepted that the superconducting flux quantum h/2e requires the existence of a phase-coherent macroscopic wave function of Cooper pairs, each with charge 2e. On the contrary, we assert that flux quantization can be better understood in terms of single-electron quantum states, localized on the scale of the coherence length and organized into a real-space phase-antiphase structure. This packing configuration is consistent with the Pauli exclusion principle for single-electron states, maintains long-range phase coherence, and is compatible with much of the BCS formalism. This also accounts for h/2e in the Josephson effect, without Cooper pairs. Experimental evidence for this alternative picture may be found in deviations from h/2e in loops and devices much smaller than the coherence length. A similar phase-antiphase structure may also account for superfluids, without the need for boson condensation.

  18. Punishment and cooperation in nature.

    PubMed

    Raihani, Nichola J; Thornton, Alex; Bshary, Redouan

    2012-05-01

    Humans use punishment to promote cooperation in laboratory experiments but evidence that punishment plays a similar role in non-human animals is comparatively rare. In this article, we examine why this may be the case by reviewing evidence from both laboratory experiments on humans and ecologically relevant studies on non-human animals. Generally, punishment appears to be most probable if players differ in strength or strategic options. Although these conditions are common in nature, punishment (unlike other forms of aggression) involves immediate payoff reductions to both punisher and target, with net benefits to punishers contingent on cheats behaving more cooperatively in future interactions. In many cases, aggression yielding immediate benefits may suffice to deter cheats and might explain the relative scarcity of punishment in nature. PMID:22284810

  19. Assessment of a cooperative workstation.

    PubMed Central

    Beuscart, R. J.; Molenda, S.; Souf, N.; Foucher, C.; Beuscart-Zephir, M. C.

    1996-01-01

    Groupware and new Information Technologies have now made it possible for people in different places to work together in synchronous cooperation. Very often, designers of this new type of software are not provided with a model of the common workspace, which is prejudicial to software development and its acceptance by potential users. The authors take the example of a task of medical co-diagnosis, using a multi-media communication workstation. Synchronous cooperative work is made possible by using local ETHERNET or public ISDN Networks. A detailed ergonomic task analysis studies the cognitive functioning of the physicians involved, compares their behaviour in the normal and the mediatized situations, and leads to an interpretation of the likely causes for success or failure of CSCW tools. PMID:8947764

  20. Shame and honour drive cooperation.

    PubMed

    Jacquet, Jennifer; Hauert, Christoph; Traulsen, Arne; Milinski, Manfred

    2011-12-23

    Can the threat of being shamed or the prospect of being honoured lead to greater cooperation? We test this hypothesis with anonymous six-player public goods experiments, an experimental paradigm used to investigate problems related to overusing common resources. We instructed the players that the two individuals who were least generous after 10 rounds would be exposed to the group. As the natural antithesis, we also test the effects of honour by revealing the identities of the two players who were most generous. The non-monetary, reputational effects induced by shame and honour each led to approximately 50 per cent higher donations to the public good when compared with the control, demonstrating that both shame and honour can drive cooperation and can help alleviate the tragedy of the commons. PMID:21632623

  1. Rural electric cooperatives IRP survey

    SciTech Connect

    Garrick, C.

    1995-11-01

    This report summarizes the integrated resource planning (IRP) practices of US rural electric cooperatives and the IRP policies which influence these practices. It was prepared by the National Renewable Energy Laboratory (NREL) and its subcontractor Garrick and Associates to assist the US Department of Energy (DOE) in satisfying the reporting requirements of Title 1, Subtitle B, Section 111(e)(3) of the Energy Policy Act of 1992 (EPAct), which states: (e) Report--Not later than 2 years after the date of the enactment of this Act, the Secretary (of the US Department of Energy) shall transmit a report to the President and to the Congress containing--(the findings from several surveys and evaluations, including:); (3) a survey of practices and policies under which electric cooperatives prepare IRPs, submit such plans to REA, and the extent to which such integrated resource planning is reflected in rates charged to customers.

  2. NASA/University Technology Cooperation

    NASA Technical Reports Server (NTRS)

    1990-01-01

    NASA is extensively engaged in cooperative technology development efforts with the nation's research universities. An example of NASA/university cooperation is the work of the Space Technology Center at the University of Kansas (KU) and the KU Center for Research, Inc. (CRINC). Directed by Professor Bill G. Barr, the Space Technology Center is one of 27 interdisciplinary centers established as part of a NASA plan to set up a network of advanced facilities across the nation. Since 1981 CRINC has been involved in a technology transfer program supported by the NASA Technology Utilization Division and by industry. The objective of the technology transfer program is to encourage industrial innovation through utilization of NASA technology through improved industry/university cooperation. At KU, research is conducted by the Industrial Innovation Laboratory and the Computer Integrated Manufacturing Laboratory which utilize graduate students in engineering and computer science as research assistants. A new project of the Space Technology Center is one designed to advance NASA objectives in "augmented telerobotics." A telerobot is programmed to respond to commands from a human operator, or to mimic the movements of its human operator. The project is being conducted under the guidance of Langley Research Center.

  3. Cooperative Transmembrane Penetration of Nanoparticles

    PubMed Central

    Zhang, Haizhen; Ji, Qiuju; Huang, Changjin; Zhang, Sulin; Yuan, Bing; Yang, Kai; Ma, Yu-qiang

    2015-01-01

    Physical penetration of lipid bilayer membranes presents an alternative pathway for cellular delivery of nanoparticles (NPs) besides endocytosis. NPs delivered through this pathway could reach the cytoplasm, thereby opening the possibility of organelle-specific targeting. Herein we perform dissipative particle dynamics simulations to elucidate the transmembrane penetration mechanisms of multiple NPs. Our simulations demonstrate that NPs’ translocation proceeds in a cooperative manner, where the interplay of the quantity and surface chemistry of the NPs regulates the translocation efficiency. For NPs with hydrophilic surfaces, the increase of particle quantity facilitates penetration, while for NPs with partly or totally hydrophobic surfaces, the opposite highly possibly holds. Moreover, a set of interesting cooperative ways, such as aggregation, aggregation-dispersion, and aggregation-dispersion-reaggregation of the NPs, are observed during the penetration process. We find that the penetration behaviors of multiple NPs are mostly dominated by the changes of the NP-membrane force components in the membrane plane direction, in addition to that in the penetration direction, suggesting a different interaction mechanism between the multiple NPs and the membrane compared with the one-NP case. These results provide a fundamental understanding in the underlying mechanisms of cooperative penetration of NPs, and shed light on the NP-based drug and gene delivery. PMID:26013284

  4. Cooperation and age structure in spatial games.

    PubMed

    Wang, Zhen; Wang, Zhen; Zhu, Xiaodan; Arenzon, Jeferson J

    2012-01-01

    We study the evolution of cooperation in evolutionary spatial games when the payoff correlates with the increasing age of players (the level of correlation is set through a single parameter, α). The demographic heterogeneous age distribution, directly affecting the outcome of the game, is thus shown to be responsible for enhancing the cooperative behavior in the population. In particular, moderate values of α allow cooperators not only to survive but to outcompete defectors, even when the temptation to defect is large and the ageless, standard α=0 model does not sustain cooperation. The interplay between age structure and noise is also considered, and we obtain the conditions for optimal levels of cooperation.

  5. Managing diversity in hospitals.

    PubMed

    Schwartz, R H; Sullivan, D B

    1993-01-01

    Hospital work force diversity, although potentially a source of creativity and improved problem solving, is often a source of political strife and the mistreatment of people based on their identification with one or another of the diverse groups that are employed in hospitals. Factors linked to these phenomena are discussed and are the basis for suggestions about how administrators can deal with the organizational pathologies that are often associated with unmanaged work force diversity.

  6. Benevolent Characteristics Promote Cooperative Behaviour among Humans

    PubMed Central

    Mylona, Kalliopi; Niblo, Graham A.

    2014-01-01

    Cooperation is fundamental to the evolution of human society. We regularly observe cooperative behaviour in everyday life and in controlled experiments with anonymous people, even though standard economic models predict that they should deviate from the collective interest and act so as to maximise their own individual payoff. However, there is typically heterogeneity across subjects: some may cooperate, while others may not. Since individual factors promoting cooperation could be used by institutions to indirectly prime cooperation, this heterogeneity raises the important question of who these cooperators are. We have conducted a series of experiments to study whether benevolence, defined as a unilateral act of paying a cost to increase the welfare of someone else beyond one's own, is related to cooperation in a subsequent one-shot anonymous Prisoner's dilemma. Contrary to the predictions of the widely used inequity aversion models, we find that benevolence does exist and a large majority of people behave this way. We also find benevolence to be correlated with cooperative behaviour. Finally, we show a causal link between benevolence and cooperation: priming people to think positively about benevolent behaviour makes them significantly more cooperative than priming them to think malevolently. Thus benevolent people exist and cooperate more. PMID:25140707

  7. Between-group competition and human cooperation.

    PubMed

    Puurtinen, Mikael; Mappes, Tapio

    2009-01-22

    A distinctive feature of human behaviour is the widespread occurrence of cooperation among unrelated individuals. Explaining the maintenance of costly within-group cooperation is a challenge because the incentive to free ride on the efforts of other group members is expected to lead to decay of cooperation. However, the costs of cooperation can be diminished or overcome when there is competition at a higher level of organizational hierarchy. Here we show that competition between groups resolves the paradigmatic 'public goods' social dilemma and increases within-group cooperation and overall productivity. Further, group competition intensifies the moral emotions of anger and guilt associated with violations of the cooperative norm. The results suggest an important role for group conflict in the evolution of human cooperation and moral emotions.

  8. Evolution of Cooperation in Public Goods Games

    NASA Astrophysics Data System (ADS)

    Xia, Cheng-Yi; Zhang, Juan-Juan; Wang, Yi-Ling; Wang, Jin-Song

    2011-10-01

    We investigate the evolution of cooperation with evolutionary public goods games based on finite populations, where four pure strategies: cooperators, defectors, punishers and loners who are unwilling to participate are considered. By adopting approximate best response dynamics, we show that the magnitude of rationality not only quantitatively explains the experiment results in [Nature (London) 425 (2003) 390], but also it will heavily influence the evolution of cooperation. Compared with previous results of infinite populations, which result in two equilibriums, we show that there merely exists a special equilibrium and the relevant high value of bounded rationality will sustain cooperation. In addition, we characterize that loner's payoff plays an active role in the maintenance of cooperation, which will only be warranted for the low and moderate values of loner's payoff. It thus indicates the effects of rationality and loner's payoff will influence the cooperation. Finally, we highlight the important result that the introduction of voluntary participation and punishment will facilitate cooperation greatly.

  9. Evolution of cooperation among mobile agents

    NASA Astrophysics Data System (ADS)

    Chen, Zhuo; Gao, Jianxi; Cai, Yunze; Xu, Xiaoming

    2011-05-01

    We study the effects of mobility on the evolution of cooperation among mobile players, which imitate collective motion of biological flocks and interact with neighbors within a prescribed radius R. Adopting the the prisoner’s dilemma game and the snowdrift game as metaphors, we find that cooperation can be maintained and even enhanced for low velocities and small payoff parameters, when compared with the case that all agents do not move. But such enhancement of cooperation is largely determined by the value of R, and for modest values of R, there is an optimal value of velocity to induce the maximum cooperation level. Besides, we find that intermediate values of R or initial population densities are most favorable for cooperation, when the velocity is fixed. Depending on the payoff parameters, the system can reach an absorbing state of cooperation when the snowdrift game is played. Our findings may help understanding the relations between individual mobility and cooperative behavior in social systems.

  10. Pervasive Selection for Cooperative Cross-Feeding in Bacterial Communities

    PubMed Central

    Germerodt, Sebastian; Bohl, Katrin; Pande, Samay; Schröter, Anja; Kaleta, Christoph; Kost, Christian

    2016-01-01

    Bacterial communities are taxonomically highly diverse, yet the mechanisms that maintain this diversity remain poorly understood. We hypothesized that an obligate and mutual exchange of metabolites, as is very common among bacterial cells, could stabilize different genotypes within microbial communities. To test this, we developed a cellular automaton to model interactions among six empirically characterized genotypes that differ in their ability and propensity to produce amino acids. By systematically varying intrinsic (i.e. benefit-to-cost ratio) and extrinsic parameters (i.e. metabolite diffusion level, environmental amino acid availability), we show that obligate cross-feeding of essential metabolites is selected for under a broad range of conditions. In spatially structured environments, positive assortment among cross-feeders resulted in the formation of cooperative clusters, which limited exploitation by non-producing auxotrophs, yet allowed them to persist at the clusters’ periphery. Strikingly, cross-feeding helped to maintain genotypic diversity within populations, while amino acid supplementation to the environment decoupled obligate interactions and favored auxotrophic cells that saved amino acid production costs over metabolically autonomous prototrophs. Together, our results suggest that spatially structured environments and limited nutrient availabilities should facilitate the evolution of metabolic interactions, which can help to maintain genotypic diversity within natural microbial populations. PMID:27314840

  11. Pervasive Selection for Cooperative Cross-Feeding in Bacterial Communities.

    PubMed

    Germerodt, Sebastian; Bohl, Katrin; Lück, Anja; Pande, Samay; Schröter, Anja; Kaleta, Christoph; Schuster, Stefan; Kost, Christian

    2016-06-01

    Bacterial communities are taxonomically highly diverse, yet the mechanisms that maintain this diversity remain poorly understood. We hypothesized that an obligate and mutual exchange of metabolites, as is very common among bacterial cells, could stabilize different genotypes within microbial communities. To test this, we developed a cellular automaton to model interactions among six empirically characterized genotypes that differ in their ability and propensity to produce amino acids. By systematically varying intrinsic (i.e. benefit-to-cost ratio) and extrinsic parameters (i.e. metabolite diffusion level, environmental amino acid availability), we show that obligate cross-feeding of essential metabolites is selected for under a broad range of conditions. In spatially structured environments, positive assortment among cross-feeders resulted in the formation of cooperative clusters, which limited exploitation by non-producing auxotrophs, yet allowed them to persist at the clusters' periphery. Strikingly, cross-feeding helped to maintain genotypic diversity within populations, while amino acid supplementation to the environment decoupled obligate interactions and favored auxotrophic cells that saved amino acid production costs over metabolically autonomous prototrophs. Together, our results suggest that spatially structured environments and limited nutrient availabilities should facilitate the evolution of metabolic interactions, which can help to maintain genotypic diversity within natural microbial populations. PMID:27314840

  12. Diversion of Drugs Within Health Care Facilities, a Multiple-Victim Crime: Patterns of Diversion, Scope, Consequences, Detection, and Prevention

    PubMed Central

    Berge, Keith H.; Dillon, Kevin R.; Sikkink, Karen M.; Taylor, Timothy K.; Lanier, William L.

    2012-01-01

    Mayo Clinic has been involved in an ongoing effort to prevent the diversion of controlled substances from the workplace and to rapidly identify and respond when such diversion is detected. These efforts have found that diversion of controlled substances is not uncommon and can result in substantial risk not only to the individual who is diverting the drugs but also to patients, co-workers, and employers. We believe that all health care facilities should have systems in place to deter controlled substance diversion and to promptly identify diversion and intervene when it is occurring. Such systems are multifaceted and require close cooperation between multiple stakeholders including, but not limited to, departments of pharmacy, safety and security, anesthesiology, nursing, legal counsel, and human resources. Ideally, there should be a broad-based appreciation of the dangers that diversion creates not only for patients but also for all employees of health care facilities, because diversion can occur at any point along a long supply chain. All health care workers must be vigilant for signs of possible diversion and must be aware of how to engage a preexisting group with expertise in investigating possible diversions. In addition, clear policies and procedures should be in place for dealing with such investigations and for managing the many possible outcomes of a confirmed diversion. This article provides an overview of the multiple types of risk that result from drug diversion from health care facilities. Further, we describe a system developed at Mayo Clinic for evaluating episodes of potential drug diversion and for taking action once diversion is confirmed. PMID:22766087

  13. Population heterogeneity promotes a preference for blind cooperation

    NASA Astrophysics Data System (ADS)

    Perez-Escudero, Alfonso; Friedman, Jonathan; Gore, Jeff

    Game theory--and common sense--recommend to carefully weigh costs and benefits before deciding on a course of action. Yet we often disapprove of people who do so, even when their actual decision benefits us. For example, we prefer people who directly agree to do us a favor over those who agree only after securing enough information to ensure that the favor will not be too costly. Why should we care about how people make their decisions, rather than just focus on the decisions themselves? Hoffman et al. (2015) have shown that such aversion to information gathering may be beneficial when it is strong enough to increase the level of cooperation. Here we show that the same type of aversion arises in heterogeneous populations, but for a different reason: individuals who seek additional information may reveal themselves to be undesirable partners, since they are less likely to cooperate in the future when conditions change. Aversion to information gathering thus facilitates preferential interactions with blind cooperators, who are more favorable partners. Due to this new mechanism the prevalence of such aversion rapidly increases with population diversity, because partner discrimination is more useful in populations which harbor partners of a more varied quality. We gratefully acknowledge funding from the Paul G. Allen Family Foundation, EMBO and Human Frontier Science Program.

  14. To cooperate or to defect? Altruism and reputation

    NASA Astrophysics Data System (ADS)

    Kułakowski, Krzysztof; Gawroński, Przemysław

    2009-09-01

    The basic difficulty in cooperation theory is to justify the cooperation. Here we propose a new approach, where players are driven by their altruism to cooperate or not. The probability of cooperation depends also on the co-player’s reputation. We find that players with positive altruism cooperate and meet cooperation. In this approach, payoffs are not relevant.

  15. The cooperative research unit program and wildlife education: Historic development, future challenges

    USGS Publications Warehouse

    Bissonette, J.A.; Loftin, C.S.; Leslie, David M.; Nordstrom, L.A.; Fleming, W.J.

    2000-01-01

    In 1932, J. N. 'Ding' Darling proposed a 3-year tripartite arrangement between the Iowa Fish and Game Commission, Iowa State University, and himself to establish the first Cooperative Wildlife Research Unit. Three years later, the Cooperative Wildlife Research Unit Program was broadened to include 9 land-grant colleges representing recognized ecoregions in the United States. In 1960, the Units were given statutory recognition by Public Law 86-686 that also included provision for establishing Cooperative Fishery Units. The Cooperative Research Unit idea has evolved to 39 Units in 2000. Today, the main cooperators of the Unit program are the land-grant university, the state fish and game or conservation agency, the U.S. Geological Survey, and the Wildlife Management Institute. The Cooperative Units mission, as stated in Public Law 86-686, remains: 'To facilitate cooperation between the Federal Government, colleges and universities, and private organizations for cooperative unit programs of research and education relating to fish and wildlife and for other purposes.' Graduate research and education continue to be the program's primary missions. In any given year >600 graduate and post-graduate students are involved. Post-graduate employment of Unit-afffiliated students is >90%. Perhaps the primary benefit to the education process is the Units' formal connection to the state cooperator and to their federal agency that might not otherwise be available to university faculty and students. Units are conduits to state and federal funding for research projects conducted by university faculty and students. The CRU program is well positioned to educate a multitalented, ethnically diverse cadre of graduate students who will be prepared not only for their first professional job but also for their career by having been instilled with a desire for life-long professional accomplishment.

  16. Teaching Diverse Learners. Diversities in the Classroom.

    ERIC Educational Resources Information Center

    Glazer, Susan Mandel

    1996-01-01

    Describes "diverse" as a socially acceptable term for both gifted children and at-risk children. Recommends describing children's specific behavior to create a more definitive picture. Includes example of observation of a "dysgraphic" child and the specific behaviors expressed, suggesting that results of observation can yield ideas about…

  17. Assessing Diverse Populations.

    ERIC Educational Resources Information Center

    Lee, Courtland C.

    This keynote address begins with examples that underscore how profoundly the issues of multiculturalism and diversity impact the consciousness of society at the end of the 20th century. Changes in assessment that can lead to assessment for change in a culturally diverse society are based on the ideas that "assessment as a process must be…

  18. Diversity in Leadership

    ERIC Educational Resources Information Center

    Beer, Janet

    2015-01-01

    This paper presents a lecture given at the 17th Annual Lecture of the Association of University Administrators (AUA). The subject of the lecture is equality and diversity in higher education (HE) leadership, or possibly the absence of equality and diversity. The author focuses on what can be done to ensure that capable women enter HE leadership…

  19. Diversity at Work.

    ERIC Educational Resources Information Center

    Sabo, Sandra R.

    2000-01-01

    Diversity in the workplace goes beyond racial, ethnic, and cultural backgrounds. It extends to those with disabilities of all types and older workers. Students must be able to acknowledge and appreciate peoples' differences and educators must integrate diversity into the classroom. (JOW)

  20. Diversity in the Workplace.

    ERIC Educational Resources Information Center

    1996

    This document contains three papers presented at a symposium on diversity in the workplace moderated by Sandra Johnson at the 1996 conference of the Academy of Human Resource Development (AHRD). "Diversity and Development: An Assessment of Equal Opportunities and the Role of HRD in the Police Service" (Rashmi Biswas, Penny Dick) examines aspects…