Non cooperative games applied to nuclear safeguards

International Nuclear Information System (INIS)

Goutal, P.

1997-01-01

This study presents the utilization of the non cooperative games in the nuclear safeguards. In order to dissuade from possible diversions of nuclear materials, an inspector has to realize a certain number of inspections in a nuclear installation. The inspector has to minimize the detection time of a diversion and the diverter has to maximize this time. A software, JADIS, is realized to obtain optimum inspection strategy for a great number of periods. Another game is studied: the infiltration game. An infiltration agent has to brake into the installation without being headed off. (A.L.B.)

Expanding Kenya's protected areas under the Convention on Biological Diversity to maximize coverage of plant diversity.

Science.gov (United States)

Scherer, Laura; Curran, Michael; Alvarez, Miguel

2017-04-01

Biodiversity is highly valuable and critically threatened by anthropogenic degradation of the natural environment. In response, governments have pledged enhanced protected-area coverage, which requires scarce biological data to identify conservation priorities. To assist this effort, we mapped conservation priorities in Kenya based on maximizing alpha (species richness) and beta diversity (species turnover) of plant communities while minimizing economic costs. We used plant-cover percentages from vegetation surveys of over 2000 plots to build separate models for each type of diversity. Opportunity and management costs were based on literature data and interviews with conservation organizations. Species richness was predicted to be highest in a belt from Lake Turkana through Mount Kenya and in a belt parallel to the coast, and species turnover was predicted to be highest in western Kenya and along the coast. Our results suggest the expanding reserve network should focus on the coast and northeastern provinces of Kenya, where new biological surveys would also fill biological data gaps. Meeting the Convention on Biological Diversity target of 17% terrestrial coverage by 2020 would increase representation of Kenya's plant communities by 75%. However, this would require about 50 times more funds than Kenya has received thus far from the Global Environment Facility. © 2016 Society for Conservation Biology.

Exponentially Enhanced Light-Matter Interaction, Cooperativities, and Steady-State Entanglement Using Parametric Amplification

Science.gov (United States)

Qin, Wei; Miranowicz, Adam; Li, Peng-Bo; Lü, Xin-You; You, J. Q.; Nori, Franco

2018-03-01

We propose an experimentally feasible method for enhancing the atom-field coupling as well as the ratio between this coupling and dissipation (i.e., cooperativity) in an optical cavity. It exploits optical parametric amplification to exponentially enhance the atom-cavity interaction and, hence, the cooperativity of the system, with the squeezing-induced noise being completely eliminated. Consequently, the atom-cavity system can be driven from the weak-coupling regime to the strong-coupling regime for modest squeezing parameters, and even can achieve an effective cooperativity much larger than 100. Based on this, we further demonstrate the generation of steady-state nearly maximal quantum entanglement. The resulting entanglement infidelity (which quantifies the deviation of the actual state from a maximally entangled state) is exponentially smaller than the lower bound on the infidelities obtained in other dissipative entanglement preparations without applying squeezing. In principle, we can make an arbitrarily small infidelity. Our generic method for enhancing atom-cavity interaction and cooperativities can be implemented in a wide range of physical systems, and it can provide diverse applications for quantum information processing.

Cooperation, but not competition, improves 4-year-old children's reasoning about others' diverse desires.

Science.gov (United States)

Jin, Xinyi; Li, Pengchao; He, Jie; Shen, Mowei

2017-05-01

Three experiments examined whether cooperation or competition affects 4-year-old children's reasoning about other people's desires-which differed from their own-in a gift selection task. Experiment 1 (N=72) found that children's performance in selecting an adult-preferred gift for an adult experimenter was enhanced by a short period of preceding cooperative, but not competitive or individualistic, play with the experimenter. Experiment 2 (N=24) ruled out the alternative explanation that children resisted satisfying their opponent after competition. Experiment 3 (N=48) replicated the cooperation advantage in selecting a gift for someone else, indicating that children's understanding of diverse desires was generally improved by cooperation but not competition. These findings support the constructivist view of social development and highlight the advantage of cooperation. Copyright © 2016 Elsevier Inc. All rights reserved.

On the relative advantage of cooperatives

DEFF Research Database (Denmark)

Albæk, Svend; Schultz, Christian

1998-01-01

We show that the fact that farmers in a cooperative individually decide how much to supply to the cooperative may serve as a commitment device for credibly (and profitably) gaining market share in competition with a profit maximizing firm......We show that the fact that farmers in a cooperative individually decide how much to supply to the cooperative may serve as a commitment device for credibly (and profitably) gaining market share in competition with a profit maximizing firm...

Analysis and Construction of Full-Diversity Joint Network-LDPC Codes for Cooperative Communications

Directory of Open Access Journals (Sweden)

Capirone Daniele

2010-01-01

Full Text Available Transmit diversity is necessary in harsh environments to reduce the required transmit power for achieving a given error performance at a certain transmission rate. In networks, cooperative communication is a well-known technique to yield transmit diversity and network coding can increase the spectral efficiency. These two techniques can be combined to achieve a double diversity order for a maximum coding rate on the Multiple-Access Relay Channel (MARC, where two sources share a common relay in their transmission to the destination. However, codes have to be carefully designed to obtain the intrinsic diversity offered by the MARC. This paper presents the principles to design a family of full-diversity LDPC codes with maximum rate. Simulation of the word error rate performance of the new proposed family of LDPC codes for the MARC confirms the full diversity.

Optimal Contract Design for Cooperative Relay Incentive Mechanism under Moral Hazard

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Nan Zhao

2015-01-01

Full Text Available Cooperative relay can effectively improve spectrum efficiency by exploiting the spatial diversity in the wireless networks. However, wireless nodes may acquire different network information with various users’ location and mobility, channels’ conditions, and other factors, which results in asymmetric information between the source and the relay nodes (RNs. In this paper, the relay incentive mechanism between relay nodes and the source is investigated under the asymmetric information. By modelling multiuser cooperative relay as a labour market, a contract model with moral hazard for relay incentive is proposed. To effectively incentivize the potential RNs to participate in cooperative relay, the optimization problems are formulated to maximize the source’s utility while meeting the feasible conditions under both symmetric and asymmetric information scenarios. Numerical simulation results demonstrate the effectiveness of the proposed contract design scheme for cooperative relay.

Blind cooperative diversity using distributed space-time coding in block fading channels

KAUST Repository

Tourki, Kamel

2010-08-01

Mobile users with single antennas can still take advantage of spatial diversity through cooperative space-time encoded transmission. In this paper, we consider a scheme in which a relay chooses to cooperate only if its source-relay channel is of an acceptable quality and we evaluate the usefulness of relaying when the source acts blindly and ignores the decision of the relays whether they may cooperate or not. In our study, we consider the regenerative relays in which the decisions to cooperate are based on a signal-to-noise ratio (SNR) threshold and consider the impact of the possible erroneously detected and transmitted data at the relays. We derive the end-to-end bit-error rate (BER) expression and its approximation for binary phase-shift keying modulation and look at two power allocation strategies between the source and the relays in order to minimize the end-to-end BER at the destination for high SNR. Some selected performance results show that computer simulations based results coincide well with our analytical results. © 2010 IEEE.

A simple carrier frequency offset synchronization strategy for multiple relay cooperative diversity ofdm system

International Nuclear Information System (INIS)

Mudassar, I.; Cheema, A.; Shoab, A.

2014-01-01

Cooperative Diversity Orthogonal Frequency Division Modulation (CD-OFDM) systems are very sensitive to synchronization errors. In CD-OFDM, synchronization is more complex because all cooperative nodes (CNs) have their own frequency oscillator and different channel path which results in different timing and carrier frequency offset (CFO) for each node. Consequently, each node has to be synchronized separately without affecting the synchronization process of other nodes. All CNs transmit simultaneously during cooperation phase (C-phase) and their aggregate signal is received at the destination node. A unique frequency domain (FD) preamble is proposed for each CN during C-phase that will allow simple separation of cooperative nodes. These FD multiplexed preambles make the synchronization problem identical to OFDMA uplink. OFDMA system typically uses highly complex iterative CFO estimators for uplink synchronization. However, a simple one-shot CFO estimator is proposed that uses repeated preamble of two OFDM symbol duration. The proposed method is computationally efficient because it relies on FFT operation for user separation and interference mitigation. Subsequently, time domain (TD) multiplication is used for CFO correction of each CN. Furthermore, a CD-OFDM protocol for data transmission is presented that suites the proposed estimator and harnesses spatial diversity. The proposed estimator shows good statistical results during simulations in AWGN and Rayleigh environments. During evaluation, estimator variance, mean square error and symbol error rate are used as performance measure. (author)

Amplify-and-Forward Cooperative Diversity for Green UWB-Based WBSNs

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Heba Shaban

2013-01-01

Full Text Available This paper proposes a novel green cooperative diversity technique based on suboptimal template-based ultra-wideband (UWB wireless body sensor networks (WBSNs using amplify-and-forward (AF relays. In addition, it analyzes the bit-error-rate (BER performance of the proposed nodes. The analysis is based on the moment-generating function (MGF of the total signal-to-noise ratio (SNR at the destination. It also provides an approximate value for the total SNR. The analysis studies the performance of equally correlated binary pulse position modulation (EC-BPPM assuming the sinusoidal and square suboptimal template pulses. Numerical results are provided for the performance evaluation of optimal and suboptimal template-based nodes with and without relay cooperation. Results show that one relay node provides ~23 dB performance enhancement at BER, which mitigates the effect of the nondesirable non-line-of-sight (NLOS links in WBSNs.

Converging evolution leads to near maximal junction diversity through parallel mechanisms in B and T cell receptors

Science.gov (United States)

Benichou, Jennifer I. C.; van Heijst, Jeroen W. J.; Glanville, Jacob; Louzoun, Yoram

2017-08-01

T and B cell receptor (TCR and BCR) complementarity determining region 3 (CDR3) genetic diversity is produced through multiple diversification and selection stages. Potential holes in the CDR3 repertoire were argued to be linked to immunodeficiencies and diseases. In contrast with BCRs, TCRs have practically no Dβ germline genetic diversity, and the question emerges as to whether they can produce a diverse CDR3 repertoire. In order to address the genetic diversity of the adaptive immune system, appropriate quantitative measures for diversity and large-scale sequencing are required. Such a diversity method should incorporate the complex diversification mechanisms of the adaptive immune response and the BCR and TCR loci structure. We combined large-scale sequencing and diversity measures to show that TCRs have a near maximal CDR3 genetic diversity. Specifically, TCR have a larger junctional and V germline diversity, which starts more 5‧ in Vβ than BCRs. Selection decreases the TCR repertoire diversity, but does not affect BCR repertoire. As a result, TCR is as diverse as BCR repertoire, with a biased CDR3 length toward short TCRs and long BCRs. These differences suggest parallel converging evolutionary tracks to reach the required diversity to avoid holes in the CDR3 repertoire.

A User Cooperation Stimulating Strategy Based on Cooperative Game Theory in Cooperative Relay Networks

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Ping Zhang

2009-01-01

Full Text Available This paper proposes a user cooperation stimulating strategy among rational users. The strategy is based on cooperative game theory and enacted in the context of cooperative relay networks. Using the pricing-based mechanism, the system is modeled initially with two nodes and a Base Station (BS. Within this framework, each node is treated as a rational decision maker. To this end, each node can decide whether to cooperate and how to cooperate. Cooperative game theory assists in providing an optimal system utility and provides fairness among users. Under different cooperative forwarding modes, certain questions are carefully investigated, including “what is each node's best reaction to maximize its utility?” and “what is the optimal reimbursement to encourage cooperation?” Simulation results show that the nodes benefit from the proposed cooperation stimulating strategy in terms of utility and thus justify the fairness between each user.

A User Cooperation Stimulating Strategy Based on Cooperative Game Theory in Cooperative Relay Networks

Directory of Open Access Journals (Sweden)

Jiang Fan

2009-01-01

Full Text Available This paper proposes a user cooperation stimulating strategy among rational users. The strategy is based on cooperative game theory and enacted in the context of cooperative relay networks. Using the pricing-based mechanism, the system is modeled initially with two nodes and a Base Station (BS. Within this framework, each node is treated as a rational decision maker. To this end, each node can decide whether to cooperate and how to cooperate. Cooperative game theory assists in providing an optimal system utility and provides fairness among users. Under different cooperative forwarding modes, certain questions are carefully investigated, including "what is each node's best reaction to maximize its utility?" and "what is the optimal reimbursement to encourage cooperation?" Simulation results show that the nodes benefit from the proposed cooperation stimulating strategy in terms of utility and thus justify the fairness between each user.

FLOUTING MAXIMS IN INDONESIA LAWAK KLUB CONVERSATION

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Rahmawati Sukmaningrum

2017-04-01

Full Text Available This study aims to identify the types of maxims flouted in the conversation in famous comedy show, Indonesia Lawak Club. Likewise, it also tries to reveal the speakers‘ intention of flouting the maxim in the conversation during the show. The writers use descriptive qualitative method in conducting this research. The data is taken from the dialogue of Indonesia Lawak club and then analyzed based on Grice‘s cooperative principles. The researchers read the dialogue‘s transcripts, identify the maxims, and interpret the data to find the speakers‘ intention for flouting the maxims in the communication. The results show that there are four types of maxims flouted in the dialogue. Those are maxim of quality (23%, maxim of quantity (11%, maxim of manner (31%, and maxim of relevance (35. Flouting the maxims in the conversations is intended to make the speakers feel uncomfortable with the conversation, show arrogances, show disagreement or agreement, and ridicule other speakers.

Genome-Based Studies of Marine Microorganisms to Maximize the Diversity of Natural Products Discovery for Medical Treatments

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Xin-Qing Zhao

2011-01-01

Full Text Available Marine microorganisms are rich source for natural products which play important roles in pharmaceutical industry. Over the past decade, genome-based studies of marine microorganisms have unveiled the tremendous diversity of the producers of natural products and also contributed to the efficiency of harness the strain diversity and chemical diversity, as well as the genetic diversity of marine microorganisms for the rapid discovery and generation of new natural products. In the meantime, genomic information retrieved from marine symbiotic microorganisms can also be employed for the discovery of new medical molecules from yet-unculturable microorganisms. In this paper, the recent progress in the genomic research of marine microorganisms is reviewed; new tools of genome mining as well as the advance in the activation of orphan pathways and metagenomic studies are summarized. Genome-based research of marine microorganisms will maximize the biodiscovery process and solve the problems of supply and sustainability of drug molecules for medical treatments.

Maximal Ratio Combining Using Channel Estimation in Chaos Based Pilot-Added DS-CDMA System with Antenna Diversity

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Meher Krishna Patel

2017-01-01

Full Text Available This paper presents an adaptive multiuser transceiver scheme for DS-CDMA systems in which pilot symbols are added to users’ data to estimate complex channel fading coefficients. The performance of receiver antenna diversity with maximal ratio combining (MRC technique is analyzed for imperfect channel estimation in flat fading environments. The complex fading coefficients are estimated using least mean square (LMS algorithm and these coefficients are utilized by the maximal ratio combiner for generating the decision variable. Probability of error in closed form is derived. Further, the effect of pilot signal power on bit error rate (BER and BER performance of multiplexed pilot and data signal transmission scenario are investigated. We have compared the performance of added and multiplexed pilot-data systems and concluded the advantages of both systems. The proposed CDMA technique uses the chaotic sequence as spreading sequence. Assuming proper synchronization, the computer simulation results demonstrate the better bit error rate performance in the presence of channel estimator in the chaotic based CDMA system and the receiver antenna diversity technique further improves the performance of the proposed system. Also, no channel estimator is required if there is no phase distortion to the transmitted signal.

Nonregenerative Dual-Hop Cooperative Links with Selection Diversity

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Karagiannidis George K

2006-01-01

Full Text Available The end-to-end performance of dual-hop cooperative diversity systems equipped with nonregenerative relays and a selection combining receiver at the destination terminal over independent and nonidentical Nakagami- fading channels is studied. Closed-form expressions for the cumulative distribution function and the probability density function of the end-to-end signal-to-noise ratio ( are presented, while analytical formulae are derived for the moments and the moment generating function. Using these statistical results, closed-form expressions for the outage probability are presented for both channel state information and fixed gain relays. Furthermore, for the case of fixed gain relay, the average end-to-end , the amount of fading, and the average bit error rate can be numerically evaluated. The proposed mathematical analysis is complemented by numerical examples, including the effects on the overall performance of the s unbalancing as well as the fading severity.

Maximizing the phylogenetic diversity of seed banks.

Science.gov (United States)

Griffiths, Kate E; Balding, Sharon T; Dickie, John B; Lewis, Gwilym P; Pearce, Tim R; Grenyer, Richard

2015-04-01

Ex situ conservation efforts such as those of zoos, botanical gardens, and seed banks will form a vital complement to in situ conservation actions over the coming decades. It is therefore necessary to pay the same attention to the biological diversity represented in ex situ conservation facilities as is often paid to protected-area networks. Building the phylogenetic diversity of ex situ collections will strengthen our capacity to respond to biodiversity loss. Since 2000, the Millennium Seed Bank Partnership has banked seed from 14% of the world's plant species. We assessed the taxonomic, geographic, and phylogenetic diversity of the Millennium Seed Bank collection of legumes (Leguminosae). We compared the collection with all known legume genera, their known geographic range (at country and regional levels), and a genus-level phylogeny of the legume family constructed for this study. Over half the phylogenetic diversity of legumes at the genus level was represented in the Millennium Seed Bank. However, pragmatic prioritization of species of economic importance and endangerment has led to the banking of a less-than-optimal phylogenetic diversity and prioritization of range-restricted species risks an underdispersed collection. The current state of the phylogenetic diversity of legumes in the Millennium Seed Bank could be substantially improved through the strategic banking of relatively few additional taxa. Our method draws on tools that are widely applied to in situ conservation planning, and it can be used to evaluate and improve the phylogenetic diversity of ex situ collections. © 2014 Society for Conservation Biology.

Non cooperative games applied to nuclear safeguards; Jeux non-cooperatifs finis appliques a la securite nucleaire

Energy Technology Data Exchange (ETDEWEB)

Goutal, P

1997-07-01

This study presents the utilization of the non cooperative games in the nuclear safeguards. In order to dissuade from possible diversions of nuclear materials, an inspector has to realize a certain number of inspections in a nuclear installation. The inspector has to minimize the detection time of a diversion and the diverter has to maximize this time. A software, JADIS, is realized to obtain optimum inspection strategy for a great number of periods. Another game is studied: the infiltration game. An infiltration agent has to brake into the installation without being headed off. (A.L.B.)

Optimal cooperation-trap strategies for the iterated rock-paper-scissors game.

Directory of Open Access Journals (Sweden)

Zedong Bi

Full Text Available In an iterated non-cooperative game, if all the players act to maximize their individual accumulated payoff, the system as a whole usually converges to a Nash equilibrium that poorly benefits any player. Here we show that such an undesirable destiny is avoidable in an iterated Rock-Paper-Scissors (RPS game involving two rational players, X and Y. Player X has the option of proactively adopting a cooperation-trap strategy, which enforces complete cooperation from the rational player Y and leads to a highly beneficial and maximally fair situation to both players. That maximal degree of cooperation is achievable in such a competitive system with cyclic dominance of actions may stimulate further theoretical and empirical studies on how to resolve conflicts and enhance cooperation in human societies.

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

Science.gov (United States)

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. © 2013 Society for Conservation Biology.

Maximal feeding with active prey-switching: A kill-the-winner functional response and its effect on global diversity and biogeography

Science.gov (United States)

Vallina, S. M.; Ward, B. A.; Dutkiewicz, S.; Follows, M. J.

2014-01-01

Predators' switching towards the most abundant prey is a mechanism that stabilizes population dynamics and helps overcome competitive exclusion of species in food webs. Current formulations of active prey-switching, however, display non-maximal feeding in which the predators' total ingestion decays exponentially with the number prey species (i.e. the diet breadth) even though the total prey biomass stays constant. We analyse three previously published multi-species functional responses which have either active switching or maximal feeding, but not both. We identify the cause of this apparent incompatibility and describe a kill-the-winner formulation that combines active switching with maximal feeding. Active switching is shown to be a community response in which some predators become prey-selective and the formulations with maximal or non-maximal feeding are implicitly assuming different food web configurations. Global simulations using a marine ecosystem model with 64 phytoplankton species belonging to 4 major functional groups show that the species richness and biogeography of phytoplankton are very sensitive to the choice of the functional response for grazing. The phytoplankton biogeography reflects the balance between the competitive abilities for nutrient uptake and the degree of apparent competition which occurs indirectly between species that share a common predator species. The phytoplankton diversity significantly increases when active switching is combined with maximal feeding through predator-mediated coexistence.

Hormonal mechanisms of cooperative behaviour

Science.gov (United States)

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

Third-party punishment increases cooperation in children through (misaligned) expectations and conditional cooperation.

Science.gov (United States)

Lergetporer, Philipp; Angerer, Silvia; Glätzle-Rützler, Daniela; Sutter, Matthias

2014-05-13

The human ability to establish cooperation, even in large groups of genetically unrelated strangers, depends upon the enforcement of cooperation norms. Third-party punishment is one important factor to explain high levels of cooperation among humans, although it is still somewhat disputed whether other animal species also use this mechanism for promoting cooperation. We study the effectiveness of third-party punishment to increase children's cooperative behavior in a large-scale cooperation game. Based on an experiment with 1,120 children, aged 7 to 11 y, we find that the threat of third-party punishment more than doubles cooperation rates, despite the fact that children are rarely willing to execute costly punishment. We can show that the higher cooperation levels with third-party punishment are driven by two components. First, cooperation is a rational (expected payoff-maximizing) response to incorrect beliefs about the punishment behavior of third parties. Second, cooperation is a conditionally cooperative reaction to correct beliefs that third party punishment will increase a partner's level of cooperation.

Cooperation prevails when individuals adjust their social ties.

Directory of Open Access Journals (Sweden)

Francisco C Santos

2006-10-01

Full Text Available 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

Social group utility maximization

CERN Document Server

Gong, Xiaowen; Yang, Lei; Zhang, Junshan

2014-01-01

This SpringerBrief explains how to leverage mobile users' social relationships to improve the interactions of mobile devices in mobile networks. It develops a social group utility maximization (SGUM) framework that captures diverse social ties of mobile users and diverse physical coupling of mobile devices. Key topics include random access control, power control, spectrum access, and location privacy.This brief also investigates SGUM-based power control game and random access control game, for which it establishes the socially-aware Nash equilibrium (SNE). It then examines the critical SGUM-b

Recent developments in cooperative control and optimization

CERN Document Server

Murphey, Robert; Pardalos, Panos

2004-01-01

Over the past several years, cooperative control and optimization has un­ questionably been established as one of the most important areas of research in the military sciences. Even so, cooperative control and optimization tran­ scends the military in its scope -having become quite relevant to a broad class of systems with many exciting, commercial, applications. One reason for all the excitement is that research has been so incredibly diverse -spanning many scientific and engineering disciplines. This latest volume in the Cooperative Systems book series clearly illustrates this trend towards diversity and creative thought. And no wonder, cooperative systems are among the hardest systems control science has endeavored to study, hence creative approaches to model­ ing, analysis, and synthesis are a must! The definition of cooperation itself is a slippery issue. As you will see in this and previous volumes, cooperation has been cast into many different roles and therefore has assumed many diverse meanings. P...

Discourse Analysis in Schizophrenic Patients on the Basis of Grice\\'s Cooperative Principles

Directory of Open Access Journals (Sweden)

Ma'soumeh Salmani

2008-07-01

Full Text Available Objective: The ultimate goal of this study is one of the discourse fields analysis, i.e. Grice's cooperative principles. Materials & Methods: In this comparative and case - control study, two groups of normal individuals and schizophrenic patients were selected by simple method from sample of convenience and interviewed based on the spontaneous part of Persian Aphasia Test. All the answers were analyzed with respect to the percent rate of errors in the 4 "cooperative maxims", and the errors were collected. Data were analyzed by Independent T Test, ANOVA, Kruskal Wallis and Mann Whitney. Results: There were significant differences between two groups in respect to all the Grice’s cooperative principles (P<0.001, maxim of quantity (P<0.001, maxim of relevance (P<0.001 and maxim of manner (P=0.02, but in maxim of quality there was no significant differeance (P=0.07. The mean percent of errors in the course of illness, education and age varieties were not significant. Conclusion: Schizophrenic patients have incoherence speech and this problem exists in the discourse field and social interactions, thus the patients frequently fail in observing the Gricean cooperative principles.

Cooperation, Fast and Slow: Meta-Analytic Evidence for a Theory of Social Heuristics and Self-Interested Deliberation.

Science.gov (United States)

Rand, David G

2016-09-01

Does cooperating require the inhibition of selfish urges? Or does "rational" self-interest constrain cooperative impulses? I investigated the role of intuition and deliberation in cooperation by meta-analyzing 67 studies in which cognitive-processing manipulations were applied to economic cooperation games (total N = 17,647; no indication of publication bias using Egger's test, Begg's test, or p-curve). My meta-analysis was guided by the social heuristics hypothesis, which proposes that intuition favors behavior that typically maximizes payoffs, whereas deliberation favors behavior that maximizes one's payoff in the current situation. Therefore, this theory predicts that deliberation will undermine pure cooperation (i.e., cooperation in settings where there are few future consequences for one's actions, such that cooperating is not in one's self-interest) but not strategic cooperation (i.e., cooperation in settings where cooperating can maximize one's payoff). As predicted, the meta-analysis revealed 17.3% more pure cooperation when intuition was promoted over deliberation, but no significant difference in strategic cooperation between more intuitive and more deliberative conditions. © The Author(s) 2016.

Conditional cooperation and confusion in public-goods experiments.

Science.gov (United States)

Burton-Chellew, Maxwell N; El Mouden, Claire; West, Stuart A

2016-02-02

Economic experiments are often used to study if humans altruistically value the welfare of others. A canonical result from public-good games is that humans vary in how they value the welfare of others, dividing into fair-minded conditional cooperators, who match the cooperation of others, and selfish noncooperators. However, an alternative explanation for the data are that individuals vary in their understanding of how to maximize income, with misunderstanding leading to the appearance of cooperation. We show that (i) individuals divide into the same behavioral types when playing with computers, whom they cannot be concerned with the welfare of; (ii) behavior across games with computers and humans is correlated and can be explained by variation in understanding of how to maximize income; (iii) misunderstanding correlates with higher levels of cooperation; and (iv) standard control questions do not guarantee understanding. These results cast doubt on certain experimental methods and demonstrate that a common assumption in behavioral economics experiments, that choices reveal motivations, will not necessarily hold.

Effect of initial fraction of cooperators on cooperative behavior in evolutionary prisoner's dilemma game.

Directory of Open Access Journals (Sweden)

Keizo Shigaki

Full Text Available We investigate the influence of initial fraction of cooperators on the evolution of cooperation in spatial prisoner's dilemma games. Compared with the results of heterogeneous networks, we find that there is a relatively low initial fraction of cooperators to guarantee higher equilibrium cooperative level. While this interesting phenomenon is contrary to the commonly shared knowledge that higher initial fraction of cooperators can provide better environment for the evolution of cooperation. To support our outcome, we explore the time courses of cooperation and find that the whole course can be divided into two sequent stages: enduring (END and expanding (EXP periods. At the end of END period, thought there is a limited number of cooperator clusters left for the case of low initial setup, these clusters can smoothly expand to hold the whole system in the EXP period. However, for high initial fraction of cooperators, superfluous cooperator clusters hinder their effective expansion, which induces many remaining defectors surrounding the cooperator clusters. Moreover, through intensive analysis, we also demonstrate that when the tendency of three cooperation cluster characteristics (cluster size, cluster number and cluster shape are consistent within END and EXP periods, the state that maximizes cooperation can be favored.

Bacterial Quorum Sensing Stabilizes Cooperation by Optimizing Growth Strategies.

Science.gov (United States)

Bruger, Eric L; Waters, Christopher M

2016-11-15

Communication has been suggested as a mechanism to stabilize cooperation. In bacteria, chemical communication, termed quorum sensing (QS), has been hypothesized to fill this role, and extracellular public goods are often induced by QS at high cell densities. Here we show, with the bacterium Vibrio harveyi, that QS provides strong resistance against invasion of a QS defector strain by maximizing the cellular growth rate at low cell densities while achieving maximum productivity through protease upregulation at high cell densities. In contrast, QS mutants that act as defectors or unconditional cooperators maximize either the growth rate or the growth yield, respectively, and thus are less fit than the wild-type QS strain. Our findings provide experimental evidence that regulation mediated by microbial communication can optimize growth strategies and stabilize cooperative phenotypes by preventing defector invasion, even under well-mixed conditions. This effect is due to a combination of responsiveness to environmental conditions provided by QS, lowering of competitive costs when QS is not induced, and pleiotropic constraints imposed on defectors that do not perform QS. Cooperation is a fundamental problem for evolutionary biology to explain. Conditional participation through phenotypic plasticity driven by communication is a potential solution to this dilemma. Thus, among bacteria, QS has been proposed to be a proximate stabilizing mechanism for cooperative behaviors. Here, we empirically demonstrate that QS in V. harveyi prevents cheating and subsequent invasion by nonproducing defectors by maximizing the growth rate at low cell densities and the growth yield at high cell densities, whereas an unconditional cooperator is rapidly driven to extinction by defectors. Our findings provide experimental evidence that QS regulation prevents the invasion of cooperative populations by QS defectors even under unstructured conditions, and they strongly support the role of

Do the women matter in co-operative banks’ boards?

Directory of Open Access Journals (Sweden)

Vittorio Boscia

2015-06-01

Full Text Available The topic of gender diversity is assuming greater importance not only for regulatory reasons. In credit cooperative field, the presence of gender diversity can qualify among the mutual aims and social sector should pursue. With reference to cooperative banks, the work aims to verify whether board gender diversity increases the creation of value for stakeholders, in terms of stakeholders’ global value added (shareholders, employees, customers, regulators, community and external environment. We propose an econometric approach based on OLS regression model; the econometric model adopted to test our research hypothesis take into account three dependent variables in order to measure the amount and the distribution of value created by each cooperative bank, like Global Value Added Index, HHI Index and GINI Index. Regarding the regressors in order to express the bank governance profile, the choice of variables is based on the results of the studies relating to bank governance-performance. Our model takes also into account other macro-economic control regressors. The model is tested on a sample of Italian cooperative banks. Previous studies on board gender diversity in cooperative banks are particularly limited as a result of limited information and opacity of this field. The existing studies are limited to analyses of the effects on performance of the separation between ownership and control or of the corporate and governance structures, neglecting the dynamics of gender diversity; recently, some authors have investigated the relationship between the composition of loan portfolios and the structure and membership of the boards of cooperative banks in Spain, without however considering the board gender diversity. Our work allows you to expand the knowledge on the issue of governance of cooperative banks. Our study proposes some indicators to assess the social and mutual performance of cooperative banks; it puts in evidence if board gender diversity

Use of a Cooperative to Interlock Contingencies and Balance the Commonwealth

Science.gov (United States)

Alavosius, Mark; Getting, Jim; Dagen, Joseph; Newsome, William; Hopkins, Bill

2009-01-01

Cooperatives are systems organized along key principles to balance the distribution of wealth across organizational members. The cooperative movement has an extensive history and has contributed to the design and operation of a large variety of endeavors that seek to maximize returns to a maximum number of stakeholders. While cooperatives are…

Configuration of Wireless Cooperative/Sensor Networks

National Research Council Canada - National Science Library

Shafiee, Hamid R; Maham, B; Vazifehdan, J

2008-01-01

.... When employing more than one antenna at each node of a wireless network is not applicable, cooperation diversity protocols exploit the inherent spatial diversity of relay channels by allowing mobile...

On the Impact of User Distribution on Cooperative Spectrum Sensing and Data Transmission with Multiuser Diversity

KAUST Repository

Rao, Anlei

2011-07-01

In this thesis, we investigate the independent but not identically distributed (i.n.i.d.) situations for spectrum sensing and data transmission. In particular, we derive the false-alarm probability and the detection probability of cooperative spectrum sensing with the scheme of energy fusion over i.n.i.d. Nakagami fading channels. Then, the performance of adaptive modulation with single-cell multiuser scheduling over i.n.i.d. Nakagami fading channels is analyzed. Closed-form expressions are derived for the average channel capacity, spectral efficiency, and bit-error-rate (BER) for both constant-power variable-rate and variable-power variable-rate uncoded M- ary quadrature amplitude modulation (M-QAM) schemes. In addition, we study the impact of time delay on the average BER of adaptive M-QAM. From the selected numerical results, we can see that cooperative spectrum sensing and multiuser diversity brings considerably better performance even over i.n.i.d. fading environments.

Evolutionary dynamics under interactive diversity

Science.gov (United States)

Su, Qi; Li, Aming; Wang, Long

2017-10-01

As evidenced by many cases in human societies, individuals often make different behavior decisions in different interactions, and adaptively adjust their behavior in changeable interactive scenarios. However, up to now, how such diverse interactive behavior affects cooperation dynamics has still remained unknown. Here we develop a general framework of interactive diversity, which models individuals’ separated behavior against distinct opponents and their adaptive adjustment in response to opponents’ strategies, to explore the evolution of cooperation. We find that interactive diversity enables individuals to reciprocate every single opponent, and thus sustains large-scale reciprocal interactions. Our work witnesses an impressive boost of cooperation for a notably extensive range of parameters and for all pairwise games. These results are robust against well-mixed and various networked populations, and against degree-normalized and cumulative payoff patterns. From the perspective of network dynamics, distinguished from individuals competing for nodes in most previous work, in this paper, the system evolves in the form of behavior disseminating along edges. We propose a theoretical method based on evolution of edges, which predicts well both the frequency of cooperation and the compact cooperation clusters. Our thorough investigation clarifies the positive role of interactive diversity in resolving social dilemmas and highlights the significance of understanding evolutionary dynamics from the viewpoint of edge dynamics.

Cooperative Opportunistic Pressure Based Routing for Underwater Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

Nadeem Javaid

2017-03-01

Full Text Available In this paper, three opportunistic pressure based routing techniques for underwater wireless sensor networks (UWSNs are proposed. The first one is the cooperative opportunistic pressure based routing protocol (Co-Hydrocast, second technique is the improved Hydrocast (improved-Hydrocast, and third one is the cooperative improved Hydrocast (Co-improved Hydrocast. In order to minimize lengthy routing paths between the source and the destination and to avoid void holes at the sparse networks, sensor nodes are deployed at different strategic locations. The deployment of sensor nodes at strategic locations assure the maximum monitoring of the network field. To conserve the energy consumption and minimize the number of hops, greedy algorithm is used to transmit data packets from the source to the destination. Moreover, the opportunistic routing is also exploited to avoid void regions by making backward transmissions to find reliable path towards the destination in the network. The relay cooperation mechanism is used for reliable data packet delivery, when signal to noise ratio (SNR of the received signal is not within the predefined threshold then the maximal ratio combining (MRC is used as a diversity technique to improve the SNR of the received signals at the destination. Extensive simulations validate that our schemes perform better in terms of packet delivery ratio and energy consumption than the existing technique; Hydrocast.

Cooperative Opportunistic Pressure Based Routing for Underwater Wireless Sensor Networks.

Science.gov (United States)

Javaid, Nadeem; Muhammad; Sher, Arshad; Abdul, Wadood; Niaz, Iftikhar Azim; Almogren, Ahmad; Alamri, Atif

2017-03-19

In this paper, three opportunistic pressure based routing techniques for underwater wireless sensor networks (UWSNs) are proposed. The first one is the cooperative opportunistic pressure based routing protocol (Co-Hydrocast), second technique is the improved Hydrocast (improved-Hydrocast), and third one is the cooperative improved Hydrocast (Co-improved Hydrocast). In order to minimize lengthy routing paths between the source and the destination and to avoid void holes at the sparse networks, sensor nodes are deployed at different strategic locations. The deployment of sensor nodes at strategic locations assure the maximum monitoring of the network field. To conserve the energy consumption and minimize the number of hops, greedy algorithm is used to transmit data packets from the source to the destination. Moreover, the opportunistic routing is also exploited to avoid void regions by making backward transmissions to find reliable path towards the destination in the network. The relay cooperation mechanism is used for reliable data packet delivery, when signal to noise ratio (SNR) of the received signal is not within the predefined threshold then the maximal ratio combining (MRC) is used as a diversity technique to improve the SNR of the received signals at the destination. Extensive simulations validate that our schemes perform better in terms of packet delivery ratio and energy consumption than the existing technique; Hydrocast.

On the Performance of In-Band Full-Duplex Cooperative Communications

KAUST Repository

Khafagy, Mohammad Galal

2016-06-01

block transmission with selective cooperation. Beyond the single-relay setting, the outage performance of different opportunistic full-duplex relay selection (FDRS) protocols is also evaluated under Rayleigh and Nakagami-m fading. It is shown that, with state-of-the-art adaptive self-interference cancellation techniques, FDRS can offer the same diversity order of its half-duplex rival while supporting a higher level of spectral efficiency. FDRS is also analyzed when adopted by a spectrum-sharing secondary system while the primary spectrum user imposes an additional interference constraint. Finally, buffer-aided hybrid half-/full-duplex cooperation is addressed. To maximize the end-to-end throughput, joint duplexing mode and link selection is studied where the system leverages the buffer and outage state information at the transmitters. All theoretic findings are corroborated with numerical simulations, with comparisons to existing protocols.

Maximizing policy learning in international committees

DEFF Research Database (Denmark)

Nedergaard, Peter

2007-01-01

, this article demonstrates that valuable lessons can be learned about policy learning, in practice and theoretically, by analysing the cooperation in the OMC committees. Using the Advocacy Coalition Framework as the starting point of analysis, 15 hypotheses on policy learning are tested. Among other things......, it is concluded that in order to maximize policy learning in international committees, empirical data should be made available to committees and provided by sources close to the participants (i.e. the Commission). In addition, the work in the committees should be made prestigious in order to attract well...

A Simulated Annealing method to solve a generalized maximal covering location problem

Directory of Open Access Journals (Sweden)

M. Saeed Jabalameli

2011-04-01

Full Text Available The maximal covering location problem (MCLP seeks to locate a predefined number of facilities in order to maximize the number of covered demand points. In a classical sense, MCLP has three main implicit assumptions: all or nothing coverage, individual coverage, and fixed coverage radius. By relaxing these assumptions, three classes of modelling formulations are extended: the gradual cover models, the cooperative cover models, and the variable radius models. In this paper, we develop a special form of MCLP which combines the characteristics of gradual cover models, cooperative cover models, and variable radius models. The proposed problem has many applications such as locating cell phone towers. The model is formulated as a mixed integer non-linear programming (MINLP. In addition, a simulated annealing algorithm is used to solve the resulted problem and the performance of the proposed method is evaluated with a set of randomly generated problems.

Looking for unity in diversity: human cooperative childcare in comparative perspective.

Science.gov (United States)

Burkart, Judith M; van Schaik, Carel; Griesser, Michael

2017-12-20

Humans engage in cooperative childcare, which includes some elements not found in other animals, such as the presence of post-reproductive helpers, extensive food sharing among adults and a pervasive sexual division of labour. In animals, cooperative offspring care has typically been studied in two different contexts. The first mainly involves helpers contributing care in cooperatively breeding family groups; the second context is allomaternal care in species usually not categorized as cooperative breeders (e.g. plural and communal breeders, often without male care). Comparative analyses suggest that cooperative breeding and allomaternal care in plural and communal breeders have distinct evolutionary origins, with humans fitting neither pathway entirely. Nevertheless, some critical proximate mechanisms of helping, including hormonal regulators, are likely to be shared across species. Other mechanisms may vary among species, such as social tolerance, proactive prosociality or conditional mother-infant bonding. These are presumably associated with specific details of the care system, such as whether all group members contribute, or whether mothers can potentially raise offspring alone. Thus, cooperative offspring care is seen in different contexts across animal lineages, but may nonetheless share several important psychological characteristics. We end by discussing how work on humans may play a unifying role in studying cooperative offspring care. © 2017 The Author(s).

Descriptive Analysis on Flouting and Hedging of Conversational Maxims in the “Post Grad” Movie

Directory of Open Access Journals (Sweden)

Nastiti Rokhmania

2012-11-01

Full Text Available This research is focused on analyzing flouting and hedging of conversational maxim of utterances used by the main characters in “Post Grad” movie. Conversational maxims are the rules of cooperative principle categorized into four categories; Maxim of Quality, Maxim of Quantity, Maxim of Relevance, and Maxim of Manner. If these maxims are used in conversations, the conversations can go smoothly. However, people often break the maxims overtly (flouting maxim and sometimes break the maxims secretly (hedging maxims when they make a conversation. This research is conducted using descriptive qualitative method based on the theory known as Grice’s Maxims. The data are in form of utterances used by the characters in “Post Grad” movie. The data analysis reveals some finding covering the formulated research question. The maxims are flouted when the speaker breaks some conversational maxims when using the utterances in the form of rhetorical strategies, such as tautology, metaphor, hyperbole, irony, and rhetorical question. On the other hand, conversational maxims are also hedged when the information is not totally accurate or unclearly stated but seems informative, well-founded, and relevant.

Conversational Implicature of Peanuts Comic Strip Based on Grice’s Maxim Theory

Directory of Open Access Journals (Sweden)

Muhartoyo Muhartoyo

2013-04-01

Full Text Available This article discusses about conversational implicature that occurs in Peanuts comic strips. The objectives of this study are to find out the implied meaning in the conversation between Charlie Brown with Lucy van Pelt and Lucy van Pelt with Linus van Pelt to evaluate the existence of maxim flouting and maxim violating in those conversations in relation to the four maxims such as quantity, quality, relation, and manner. Likewise, this study attempts to find out the reason for using conversational implicature in a comic strip. The writers uses a qualitative method with library research concerning to Grice’s maxim theory to analyze the conversational implicature. Based on the analysis, it can be concluded that all the comics that comprise 14 comics generate conversational implicature since all the characters breach rules of maxim. The result of this analysis shows that flouting maxim of manner has the highest occurrence of conversational implicature and the least occurrences belong to flouting maxim of relation and violating maxim of quantity. Moreover, the writers concludes that to make a successful communication ideally the speaker and the hearer to cooperate in the conversation by saying explicitly so the hearer can grasp the meaning as the goal of communication is to deliver a message to the hearer.  

Encouraging Interaction by Applying Cooperative Learning

Directory of Open Access Journals (Sweden)

González Sonia Helena

2001-08-01

Full Text Available A project was conducted in order to improve oral interaction in English by applying cooperative learning to students of seventh grade. These students have lower levels of oral production and attend Marco Fidel Suárez public school. So, I decided to choose topics related to real life and to plan a series of activities of sensitization to create stable work groups and to increase oral interaction. According to the analysis and results, I can say that cooperative work and the oral activities help the students increase oral production, express better and use a foreign language with more security. In spite of the results, I consider that cooperative learning needs more time so that it can be successful. Students must have the will to cooperate. Only when students have that good will and can work together is the potential of acquisition of knowledge maximized.

Factors that influence cooperation in networks for innovation and learning

NARCIS (Netherlands)

Sie, Rory; Bitter-Rijpkema, Marlies; Stoyanov, Slavi; Sloep, Peter

2018-01-01

Networked cooperation fails if the available partnerships remain opaque. A literature review and Delphi study uncovered the elements of a fruitful partnership. They relate to personality, diversity, cooperation, and management. Innovation networks and learning networks share the same cooperative

Interplay between cooperation-enhancing mechanisms in evolutionary games with tag-mediated interactions

Science.gov (United States)

Hadzibeganovic, Tarik; Stauffer, Dietrich; Han, Xiao-Pu

2018-04-01

Cooperation is fundamental for the long-term survival of biological, social, and technological networks. Previously, mechanisms for the enhancement of cooperation, such as network reciprocity, have largely been studied in isolation and with often inconclusive findings. Here, we present an evolutionary, multiagent-based, and spatially explicit computer model to specifically address the interactive interplay between such mechanisms. We systematically investigate the effects of phenotypic diversity, network structure, and rewards on cooperative behavior emerging in a population of reproducing artificial decision makers playing tag-mediated evolutionary games. Cooperative interactions are rewarded such that both the benefits of recipients and costs of donators are affected by the reward size. The reward size is determined by the number of cooperative acts occurring within a given reward time frame. Our computational experiments reveal that small reward frames promote unconditional cooperation in populations with both low and high diversity, whereas large reward frames lead to cycles of conditional and unconditional strategies at high but not at low diversity. Moreover, an interaction between rewards and spatial structure shows that relative to small reward frames, there is a strong difference between the frequency of conditional cooperators populating rewired versus non-rewired networks when the reward frame is large. Notably, in a less diverse population, the total number of defections is comparable across different network topologies, whereas in more diverse environments defections become more frequent in a regularly structured than in a rewired, small-world network of contacts. Acknowledging the importance of such interaction effects in social dilemmas will have inevitable consequences for the future design of cooperation-enhancing protocols in large-scale, distributed, and decentralized systems such as peer-to-peer networks.

Aspects of multiuser MIMO for cell throughput maximization

DEFF Research Database (Denmark)

Bauch, Gerhard; Tejera, Pedro; Guthy, Christian

2007-01-01

We consider a multiuser MIMO downlink scenario where the resources in time, frequency and space are allocated such that the total cell throughput is maximized. This is achieved by exploiting multiuser diversity, i.e. the physical resources are allocated to the user with the highest SNR. We assume...

Diversity Order Results for MIMO Optical Wireless Communications

KAUST Repository

Sapenov, Yerzhan

2017-09-21

An optical wireless multiple-input multiple-output (MIMO) communication system employing intensity-modulation direct-detection (IM/DD) is considered. The maximal diversity order of the channel is characterized by studying the outage probability. Then, spatial repetition coding (RC) is shown to be diversity-optimal as it achieves the channel’s maximal diversity order. This diversity order is given by a simple expression which is suitable for any channel statistics of practical interest. The results are specialized to some practical channel statistics, and numerical results are provided to verify the results.

Diversity Order Results for MIMO Optical Wireless Communications

KAUST Repository

Sapenov, Yerzhan; Chaaban, Anas; Rezki, Zouheir; Abdallah, Mohamed; Qaraqe, Khalid; Alouini, Mohamed-Slim

2017-01-01

An optical wireless multiple-input multiple-output (MIMO) communication system employing intensity-modulation direct-detection (IM/DD) is considered. The maximal diversity order of the channel is characterized by studying the outage probability. Then, spatial repetition coding (RC) is shown to be diversity-optimal as it achieves the channel’s maximal diversity order. This diversity order is given by a simple expression which is suitable for any channel statistics of practical interest. The results are specialized to some practical channel statistics, and numerical results are provided to verify the results.

Tri-maximal vs. bi-maximal neutrino mixing

International Nuclear Information System (INIS)

Scott, W.G

2000-01-01

It is argued that data from atmospheric and solar neutrino experiments point strongly to tri-maximal or bi-maximal lepton mixing. While ('optimised') bi-maximal mixing gives an excellent a posteriori fit to the data, tri-maximal mixing is an a priori hypothesis, which is not excluded, taking account of terrestrial matter effects

Planning for partnerships: Maximizing surge capacity resources through service learning.

Science.gov (United States)

Adams, Lavonne M; Reams, Paula K; Canclini, Sharon B

2015-01-01

Infectious disease outbreaks and natural or human-caused disasters can strain the community's surge capacity through sudden demand on healthcare activities. Collaborative partnerships between communities and schools of nursing have the potential to maximize resource availability to meet community needs following a disaster. This article explores how communities can work with schools of nursing to enhance surge capacity through systems thinking, integrated planning, and cooperative efforts.

Application of marginal calculation in managing a cooperative company

Directory of Open Access Journals (Sweden)

Danuta Mierzwa

2011-01-01

Full Text Available In the market economy the basic subject is a private enterprise dealing with the production of goods and services in order to maximize profit. The neoclassical microeconomics focuses on examining only these enterprises on the market, which strive to maximize profit within certain limitations in a rational way. Acc. to the act of September 1982 on the co-operative law (The Journal of Laws 1982, no 30, pos. 2010, a cooperative company belongs to a group of private enterprises. However, it is called a non-profit enterprise. Nevertheless, cooperative companies on the market are seldom confronted with capital companies. In the market economy it is a rare situation for a company not to be threatened by competition. And even if such a situation does happen, it is always connected with limited demand. Thus the following question may be asked: can a co-operative company, if it wants to become rational, utilize the marginalization theory in order to determine its general balance? The author is trying to answer this question in her article, selecting an agricultural supply co-operative for her analysis. Using the graphical method, she determines various types of optimums, at the same time stating what importance it has for the members and what position the co-perative holds on the market. In the conclusion she emphasizes that the difficulties with applying the marginalization theory in the co-operative companies are brought about by the way decisions are taken and these subjects are managed, and may be the reason why many of these enterprises are closed down.

Minefield Mapping Using Cooperative Multirobot Systems

Directory of Open Access Journals (Sweden)

Alaa Khamis

2012-01-01

Full Text Available This paper presents a team-theoretic approach to cooperative multirobot systems. The individual actions of the robots are controlled by the Belief-Desire-Intention model to endow the robots with the know-how needed to execute these actions deliberately. The cooperative behaviors between the heterogeneous robots are governed by the Team-Log theory to endow all the robots in the team with the know-how-to-cooperate and determine the team members’ commitments to each other despite their different types, properties, and goals. The proposed approach is tested for validity with the real life problem of minefield mapping. Different minefield sweeping strategies are studied to control the mobility of the mobile sweepers within the minefield in order to maximize the area coverage and improve picture compilation capability of the multirobot system.

An Enhanced Genetic Approach to Composing Cooperative Learning Groups for Multiple Grouping Criteria

Science.gov (United States)

Hwang, Gwo-Jen; Yin, Peng-Yeng; Hwang, Chi-Wei; Tsai, Chin-Chung

2008-01-01

Cooperative learning is known to be an effective educational strategy in enhancing the learning performance of students. The goal of a cooperative learning group is to maximize all members' learning efficacy. This is accomplished via promoting each other's success, through assisting, sharing, mentoring, explaining, and encouragement. To achieve…

Biological interactions and cooperative management of multiple species.

Science.gov (United States)

Jiang, Jinwei; Min, Yong; Chang, Jie; Ge, Ying

2017-01-01

Coordinated decision making and actions have become the primary solution for the overexploitation of interacting resources within ecosystems. However, the success of coordinated management is highly sensitive to biological, economic, and social conditions. Here, using a game theoretic framework and a 2-species model that considers various biological relationships (competition, predation, and mutualism), we compute cooperative (or joint) and non-cooperative (or separate) management equilibrium outcomes of the model and investigate the effects of the type and strength of the relationships. We find that cooperation does not always show superiority to non-cooperation in all biological interactions: (1) if and only if resources are involved in high-intensity predation relationships, cooperation can achieve a win-win scenario for ecosystem services and resource diversity; (2) for competitive resources, cooperation realizes higher ecosystem services by sacrificing resource diversity; and (3) for mutual resources, cooperation has no obvious advantage for either ecosystem services or resource evenness but can slightly improve resource abundance. Furthermore, by using a fishery model of the North California Current Marine Ecosystem with 63 species and seven fleets, we demonstrate that the theoretical results can be reproduced in real ecosystems. Therefore, effective ecosystem management should consider the interconnection between stakeholders' social relationship and resources' biological relationships.

Cooperative learning in 21st century

Directory of Open Access Journals (Sweden)

David W. Johnson

2014-10-01

Full Text Available The 21st century brings four important challenges in which cooperation plays a central role: (1 a rapidly increasing global interdependence that will result in increasing local diversity as well as more frequent and intense conflicts, (2 the increasing number of democracies throughout the world, (3 the need for creative entrepreneurs, and (4 the growing importance of interpersonal relationships that affect the development of personal identity. The tools for meeting these challenges include cooperative learning. In this article the nature of cooperative learning will be reviewed, the underlying theory of social interdependence will be discussed, and the results of the research on cooperative learning will be briefly reviewed. The way in which cooperative learning contributes to meeting the four challenges will then be discussed.

A Localization Based Cooperative Routing Protocol for Underwater Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

Nadeem Javaid

2017-01-01

Full Text Available Localization is one of the major aspects in underwater wireless sensor networks (UWSNs. Therefore, it is important to know the accurate position of the sensor node in large scale applications like disaster prevention, tactical surveillance, and monitoring. Due to the inefficiency of the global positioning system (GPS in UWSN, it is very difficult to localize a node in underwater environment compared to terrestrial networks. To minimize the localization error and enhance the localization coverage of the network, two routing protocols are proposed; the first one is mobile autonomous underwater vehicle (MobiL-AUV and the second one is cooperative MobiL (CO-MobiL. In MobiL-AUV, AUVs are deployed and equipped with GPS and act as reference nodes. These reference nodes are used to localize all the nonlocalized ordinary sensor nodes in order to reduce the localization error and maximize the network coverage. CO-MobiL is presented in order to improve the network throughput by using the maximal ratio combining (MRC as diversity technique which combines both signals, received from the source and received from the relay at the destination. It uses amplify-and-forward (AF mechanism to improve the signal between the source and the destination. To support our claims, extensive simulations are performed.

Firms, nonprofits, and cooperatives : A theory of organizational choice

NARCIS (Netherlands)

Herbst, Patrick; Prüfer, Jens

We formalize the difference between profit-maximizing firms, nonprofits, and cooperatives and identify optimal organizational choice in a model of quality provision. Firms provide lowest and nonprofits highest levels of quality. Efficiency, however, depends on the competitive environment, the

The evolution of cooperation on geographical networks

Science.gov (United States)

Li, Yixiao; Wang, Yi; Sheng, Jichuan

2017-11-01

We study evolutionary public goods game on geographical networks, i.e., complex networks which are located on a geographical plane. The geographical feature effects in two ways: In one way, the geographically-induced network structure influences the overall evolutionary dynamics, and, in the other way, the geographical length of an edge influences the cost when the two players at the two ends interact. For the latter effect, we design a new cost function of cooperators, which simply assumes that the longer the distance between two players, the higher cost the cooperator(s) of them have to pay. In this study, network substrates are generated by a previous spatial network model with a cost-benefit parameter controlling the network topology. Our simulations show that the greatest promotion of cooperation is achieved in the intermediate regime of the parameter, in which empirical estimates of various railway networks fall. Further, we investigate how the distribution of edges' geographical costs influences the evolutionary dynamics and consider three patterns of the distribution: an approximately-equal distribution, a diverse distribution, and a polarized distribution. For normal geographical networks which are generated using intermediate values of the cost-benefit parameter, a diverse distribution hinders the evolution of cooperation, whereas a polarized distribution lowers the threshold value of the amplification factor for cooperation in public goods game. These results are helpful for understanding the evolution of cooperation on real-world geographical networks.

Energy Efficient Authentication and Authorization for Multinode Cooperative Connectivity and Reliability

DEFF Research Database (Denmark)

Rohokale, Vandana M.

2013-01-01

their effective QoS via cooperation. The performance of wireless networks is greatly affected by some of the channel parameters such as bandwidth and power scarcity, multi-user interference, non-reliability due to signal fading, vulnerability to the attacks, etc. The cooperative diversity mechanism makes use...... of the benefits of wireless sensor network scalability in terms of cooperative resource sharing wherein multiple diversity channels are created that results into the higher transmission rates, increased throughput and coverage range, improvement in reliability and end-to-end performance and much more. Cooperative......Wireless communication is a great revolution but it still suffers from limited battery life, broken connections from multi-path fading and insufficient coverage. Simple cooperation can mak a big difference in coverage range, energy and battery life. In CWC, the active nodes may increase...

Cooperative Wireless Communications and Physical Layer Security : State of the Art

DEFF Research Database (Denmark)

Rohokale, Vandana M.; Prasad, Neeli R.; Prasad, Ramjee

2012-01-01

in the mobile equipment is not feasible due to resource constraints. Cooperative wireless communication (CWC) is the upcoming virtual MIMO technique to combat fading and achieve diversity through user cooperation. Physical layer security (PLS) is the imminent security guarantee for the cooperative communication....

Simultaneous Wireless Power Transfer and Secure Multicasting in Cooperative Decode-and-Forward Relay Networks.

Science.gov (United States)

Lee, Jong-Ho; Sohn, Illsoo; Kim, Yong-Hwa

2017-05-16

In this paper, we investigate simultaneous wireless power transfer and secure multicasting via cooperative decode-and-forward (DF) relays in the presence of multiple energy receivers and eavesdroppers. Two scenarios are considered under a total power budget: maximizing the minimum harvested energy among the energy receivers under a multicast secrecy rate constraint; and maximizing the multicast secrecy rate under a minimum harvested energy constraint. For both scenarios, we solve the transmit power allocation and relay beamformer design problems by using semidefinite relaxation and bisection technique. We present numerical results to analyze the energy harvesting and secure multicasting performances in cooperative DF relay networks.

Performance study and optimization of cooperative diversity networks with co-channel interference

KAUST Repository

Ikki, Salama Said

2014-01-01

In this paper, we investigate the effect of co-channel interference on the performance of cooperative diversity networks with amplify-and-forward (AF) relaying. We consider both conventional and opportunistic relaying. First, we obtain a tight upper-bound for the equivalent signal-to-interference-plus-noise ratio (SINR) at the destination. Subsequently, the cumulative distribution function (CDF), probability density function (PDF) and moment generating function (MGF) of the effective SINR are determined based on the upper-bound. Expressions for the error probabilities in both conventional and opportunistic relaying are derived utilizing the statistical characterization of the effective SINR. We also derive an approximate PDF of the equivalent instantaneous SINR at the destination. This leads to a simple and general asymptotic error probability expression which facilitates better insight into the effect of different system parameters on the error probability. Furthermore, we investigate the problem of optimum resource allocation in the network aiming at improving performance in the presence of resource constraints. We present numerical results that illustrate the excellent match between the analytical results and the simulation results, and the performance enhancement resulting from the proposed optimal resource allocation. © 2014 IEEE.

MMCD: Cooperative Downloading for Highway

OpenAIRE

OTA, Kaoru; DONG, Mianxiong; CHANG, Shan; ZHU, Hongzi

2015-01-01

Advances in low-power wireless communications and micro-electronics make a great impact on a transportation system and pervasive deployment of road-side units (RSU) is promising to provide drive-thru Internet to vehicular users anytime and anywhere. Downloading data packets from the RSU, however, is not always reliable because of high mobility of vehicles and high contention among vehicular users. Using inter-vehicle communication, cooperative downloading can maximize the amount of data packe...

Cooperation schemes for rate enhancement in detect-and-forward relay channels

KAUST Repository

Benjillali, Mustapha; Szczeciński, Leszek L.; Alouini, Mohamed-Slim

2010-01-01

an adaptive cooperation scheme based on the maximization of the information rate at the destination which needs to observe only the average signal-to-noise ratios of direct and relaying links. ©2010 IEEE.

Simultaneous Wireless Power Transfer and Secure Multicasting in Cooperative Decode-and-Forward Relay Networks

Science.gov (United States)

Lee, Jong-Ho; Sohn, Illsoo; Kim, Yong-Hwa

2017-01-01

In this paper, we investigate simultaneous wireless power transfer and secure multicasting via cooperative decode-and-forward (DF) relays in the presence of multiple energy receivers and eavesdroppers. Two scenarios are considered under a total power budget: maximizing the minimum harvested energy among the energy receivers under a multicast secrecy rate constraint; and maximizing the multicast secrecy rate under a minimum harvested energy constraint. For both scenarios, we solve the transmit power allocation and relay beamformer design problems by using semidefinite relaxation and bisection technique. We present numerical results to analyze the energy harvesting and secure multicasting performances in cooperative DF relay networks. PMID:28509841

Simultaneous Wireless Power Transfer and Secure Multicasting in Cooperative Decode-and-Forward Relay Networks

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Jong-Ho Lee

2017-05-01

Full Text Available In this paper, we investigate simultaneous wireless power transfer and secure multicasting via cooperative decode-and-forward (DF relays in the presence of multiple energy receivers and eavesdroppers. Two scenarios are considered under a total power budget: maximizing the minimum harvested energy among the energy receivers under a multicast secrecy rate constraint; and maximizing the multicast secrecy rate under a minimum harvested energy constraint. For both scenarios, we solve the transmit power allocation and relay beamformer design problems by using semidefinite relaxation and bisection technique. We present numerical results to analyze the energy harvesting and secure multicasting performances in cooperative DF relay networks.

Study on cooperative active sensing system

International Nuclear Information System (INIS)

Tsukune, Hideo; Kita, Nobuyuki; Hirai, Shigeoki; Kuniyoshi, Yasuo; Hara, Isao; Matsui, Toshihiro

1999-01-01

In order to realize autonomous type nuclear plant, three-dimensional geometrical modelling method, and a basic technology on information collection and processing system preparation in some nuclear basic technology developments such as 'study on system evaluation of nuclear facility furnished with artificial intelligence for nuclear power' and 'study on adaptability evaluation of information collection and processing system into autonomous type plant' had already been developed. In this study, a study on sensing system required for constructing robot groups capable of conducting autonomously traveling inspection and maintenance in large scale, complicated and diverse plant has been processed by aiming at establishment of dispersed cooperative intelligent system technology. In 1997 fiscal year, integration of cooperative visual sensing technique was attempted. And, at the same time, upgrading of individual element technology and transportation method essential to the integrated system were investigated. As a result, an operative active sensing prototype system due to transportation robot groups furnished with real time processing capacity on diverse informations by integration of cooperative active sensing technique and real time active sensing technique developed independently plural transportation robot. (G.K.)

Incentivize Spectrum Leasing in Cognitive Radio Networks by Exploiting Cooperative Retransmission

Directory of Open Access Journals (Sweden)

Xiaoyan Wang

2015-07-01

Full Text Available This paper addresses the spectrum leasing issue in cognitive radio networks by exploiting the secondary user’s cooperative retransmission. In contrast with the previous researches that focuses on cancellationbased or coding-based cooperative retransmissions, we propose a novel trading-based mechanism to facilitate the cooperative retransmission for cognitive radio networks. By utilizing the Stackelberg game model, we incentivize the otherwise non-cooperative users by maximizing their utilities in terms of transmission rates and economic profit. We analyze the existence of the unique Nash equilibrium of the game, and provide the optimal solutions with corresponding constraints. Numerical results demonstrate the efficiency of the proposed mechanism, under which the performance of the whole system could be substantially improved.

A new model in teaching undergraduate research: A collaborative approach and learning cooperatives.

Science.gov (United States)

O'Neal, Pamela V; McClellan, Lynx Carlton; Jarosinski, Judith M

2016-05-01

Forming new, innovative collaborative approaches and cooperative learning methods between universities and hospitals maximize learning for undergraduate nursing students in a research course and provide professional development for nurses on the unit. The purpose of this Collaborative Approach and Learning Cooperatives (CALC) Model is to foster working relations between faculty and hospital administrators, maximize small group learning of undergraduate nursing students, and promote onsite knowledge of evidence based care for unit nurses. A quality improvement study using the CALC Model was implemented in an undergraduate nursing research course at a southern university. Hospital administrators provided a list of clinical concerns based on national performance outcome measures. Undergraduate junior nursing student teams chose a clinical question, gathered evidence from the literature, synthesized results, demonstrated practice application, and developed practice recommendations. The student teams developed posters, which were evaluated by hospital administrators. The administrators selected several posters to display on hospital units for continuing education opportunity. This CALC Model is a systematic, calculated approach and an economically feasible plan to maximize personnel and financial resources to optimize collaboration and cooperative learning. Universities and hospital administrators, nurses, and students benefit from working together and learning from each other. Copyright © 2016 Elsevier Ltd. All rights reserved.

Stochastic heterogeneous interaction promotes cooperation in spatial prisoner's dilemma game.

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Ping Zhu

Full Text Available Previous studies mostly investigate player's cooperative behavior as affected by game time-scale or individual diversity. In this paper, by involving both time-scale and diversity simultaneously, we explore the effect of stochastic heterogeneous interaction. In our model, the occurrence of game interaction between each pair of linked player obeys a random probability, which is further described by certain distributions. Simulations on a 4-neighbor square lattice show that the cooperation level is remarkably promoted when stochastic heterogeneous interaction is considered. The results are then explained by investigating the mean payoffs, the mean boundary payoffs and the transition probabilities between cooperators and defectors. We also show some typical snapshots and evolution time series of the system. Finally, the 8-neighbor square lattice and BA scale-free network results indicate that the stochastic heterogeneous interaction can be robust against different network topologies. Our work may sharpen the understanding of the joint effect of game time-scale and individual diversity on spatial games.

Phenomenology of maximal and near-maximal lepton mixing

International Nuclear Information System (INIS)

Gonzalez-Garcia, M. C.; Pena-Garay, Carlos; Nir, Yosef; Smirnov, Alexei Yu.

2001-01-01

The possible existence of maximal or near-maximal lepton mixing constitutes an intriguing challenge for fundamental theories of flavor. We study the phenomenological consequences of maximal and near-maximal mixing of the electron neutrino with other (x=tau and/or muon) neutrinos. We describe the deviations from maximal mixing in terms of a parameter ε(equivalent to)1-2sin 2 θ ex and quantify the present experimental status for |ε| e mixing comes from solar neutrino experiments. We find that the global analysis of solar neutrino data allows maximal mixing with confidence level better than 99% for 10 -8 eV 2 ∼ 2 ∼ -7 eV 2 . In the mass ranges Δm 2 ∼>1.5x10 -5 eV 2 and 4x10 -10 eV 2 ∼ 2 ∼ -7 eV 2 the full interval |ε| e mixing in atmospheric neutrinos, supernova neutrinos, and neutrinoless double beta decay

Energy-Efficient Cooperative Techniques for Infrastructure-to-Vehicle Communications

OpenAIRE

Nguyen , Tuan-Duc; Berder , Olivier; Sentieys , Olivier

2011-01-01

International audience; In wireless distributed networks, cooperative relay and cooperative Multi-Input Multi-Output (MIMO) techniques can be used to exploit the spatial and temporal diversity gain in order to increase the performance or reduce the transmission energy consumption. The energy efficiency of cooperative MIMO and relay techniques is then very useful for the Infrastructure to Vehicle (I2V) and Infrastructure to Infrastructure (I2I) communications in Intelligent Transport Systems (I...

Evolving and Strengthening the Cooperative Approach for Agroforestry Farmers in Bangladesh: Lessons Learned from the Shimogo Cooperative in Japan

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Kazi Kamrul Islam

2018-02-01

Full Text Available Although an agro-based country, the farmers of Bangladesh do not receive significant returns from their products, due to some obstacles blocking the achievement of this ultimate goal. This study tries to identify the major challenges of the agroforestry product supply chains in Bangladesh, and offer an alternative solution through the involvement and experiences of farmer cooperatives within a Japanese cooperative model. The objectives were outfitted by two case studies, and the Bangladesh case clearly showed that the involvement of many intermediaries in agroforestry product supply chains was one of the main obstacles that stunted the outcomes of the agroforestry programs. The intermediaries have maximized their profit by buying the farmer products at low prices and selling them back at higher prices, which resulted in high marketing margins. Meanwhile, the Japanese case study had articulated that the farmer-driven cooperative approach, with its good marketing strategies and service functions, could successfully eliminate the intermediaries’ involvement in farmer products, and make a cooperative a strong economic organization. Despite a few challenges, the farmer-driven Japanese cooperative approach would be a good solution that could tackle the middleman problem, and make agroforestry a sustainable production system in Bangladesh.

Friendship-based partner switching promotes cooperation in heterogeneous populations

Science.gov (United States)

Chen, Wei; Wu, Te; Li, Zhiwu; Wang, Long

2016-02-01

The forming of human social ties tends to be with similar individuals. This study concentrates on the emergence of cooperation among heterogeneous populations. A simple model is proposed by considering the impact of interplay between the evolution of strategies and that of social partnerships on cooperation dynamics. Whenever two individuals acquire the rewards by playing prisoner's dilemma game with each other, the friendship (friendship is quantified as the weight of a link) between the two individuals deepens. Individuals can switch off the social ties with the partners who are unfriendly and rewire to similar new ones. Under this partner switching mechanism, population structure is divided into several groups and cooperation can prevail. It is observed that the frequent tendency of partner switching can lead to the enhancement of cooperative behavior under the enormous temptation to defect. Moreover, the influence of discounting the relationship between different individuals is also investigated. Meanwhile, the cooperation prevails when the adjustment of friendships mainly depends on the incomes of selected individuals rather than that of their partners. Finally, it is found that too similar population fail to maximize the cooperation and there exists a moderate similarity that can optimize cooperation.

Avian cooperative breeding: Old hypotheses and new directions.

Science.gov (United States)

Heinsohn, R G; Cockburn, A; Mulder, R A

1990-12-01

In cooperatively breeding birds, individuals that appear capable of reproducing on their own may instead assist others with their breeding efforts. Research into avian cooperative breeding has attempted to reconcile the apparent altruism of this behaviour with maximization of inclusive fitness. Most explanations of cooperative breeding have suggested that philopatry is enforced by ecological constraints, such as a shortage of resources critical to breeding. Non-dispersers may then benefit both directly and indirectly from contributing at the nest. Recent research has shown that such benefits may be sufficient to promote philopatry, without the need for ecological constraints, and emphasizes that consideration of both costs and benefits of philopatry is essential for a comprehensive approach to the problem. The growing body of data from long-term studies of different species should combine with an improved phylogenetic perspective on cooperative breeding, to provide a useful base for future comparative analyses and experimentation. Copyright © 1990. Published by Elsevier Ltd.

Power allocation for target detection in radar networks based on low probability of intercept: A cooperative game theoretical strategy

Science.gov (United States)

Shi, Chenguang; Salous, Sana; Wang, Fei; Zhou, Jianjiang

2017-08-01

Distributed radar network systems have been shown to have many unique features. Due to their advantage of signal and spatial diversities, radar networks are attractive for target detection. In practice, the netted radars in radar networks are supposed to maximize their transmit power to achieve better detection performance, which may be in contradiction with low probability of intercept (LPI). Therefore, this paper investigates the problem of adaptive power allocation for radar networks in a cooperative game-theoretic framework such that the LPI performance can be improved. Taking into consideration both the transmit power constraints and the minimum signal to interference plus noise ratio (SINR) requirement of each radar, a cooperative Nash bargaining power allocation game based on LPI is formulated, whose objective is to minimize the total transmit power by optimizing the power allocation in radar networks. First, a novel SINR-based network utility function is defined and utilized as a metric to evaluate power allocation. Then, with the well-designed network utility function, the existence and uniqueness of the Nash bargaining solution are proved analytically. Finally, an iterative Nash bargaining algorithm is developed that converges quickly to a Pareto optimal equilibrium for the cooperative game. Numerical simulations and theoretic analysis are provided to evaluate the effectiveness of the proposed algorithm.

Special Agents Can Promote Cooperation in the Population

Science.gov (United States)

Wang, Xin; Han, Jing; Han, Huawei

2011-01-01

Cooperation is ubiquitous in our real life but everyone would like to maximize her own profits. How does cooperation occur in the group of self-interested agents without centralized control? Furthermore, in a hostile scenario, for example, cooperation is unlikely to emerge. Is there any mechanism to promote cooperation if populations are given and play rules are not allowed to change? In this paper, numerical experiments show that complete population interaction is unfriendly to cooperation in the finite but end-unknown Repeated Prisoner's Dilemma (RPD). Then a mechanism called soft control is proposed to promote cooperation. According to the basic idea of soft control, a number of special agents are introduced to intervene in the evolution of cooperation. They comply with play rules in the original group so that they are always treated as normal agents. For our purpose, these special agents have their own strategies and share knowledge. The capability of the mechanism is studied under different settings. We find that soft control can promote cooperation and is robust to noise. Meanwhile simulation results demonstrate the applicability of the mechanism in other scenarios. Besides, the analytical proof also illustrates the effectiveness of soft control and validates simulation results. As a way of intervention in collective behaviors, soft control provides a possible direction for the study of reciprocal behaviors. PMID:22216202

Emotions and cooperation in economic games.

Science.gov (United States)

Haselhuhn, Michael P; Mellers, Barbara A

2005-04-01

In this paper, we examine decisions to cooperate in economic games. We investigate which payoffs give players the greatest pleasure and whether the pleasure they feel about payoffs predicts their decisions to cooperate. To do this, we modify the ultimatum and dictator games by asking players to consider a fixed set of offers and report their preferences over all offers. Players also report the pleasure they imagine feeling from each possible payoff. Results show that players differ in the extent to which they derive pleasure from fairness or greediness. They also differ in the extent to which their choices depend on what we call "strategic" and "non-strategic" pleasure. Strategic pleasure is the expected pleasure of offers, whereas non-strategic pleasure is the pleasure of accepted payoffs. Players whose pleasure primarily depends on larger payoffs tend to make fair offers in the ultimatum game and selfish offers in the dictator game. They maximize strategic pleasure in the ultimatum game and non-strategic pleasure in the dictator game. Players who derive greater pleasure from fairness tend to act fairly in both games. These players maximize non-strategic pleasure. Brain imaging studies should address the question of whether the observed differences in pleasure and preference are systematically linked to differences in neurological activation.

Diversity of neighborhoods promotes cooperation in evolutionary social dilemmas

Science.gov (United States)

Ma, Yongjuan; Lu, Jun; Shi, Lei

2017-02-01

Explaining the evolution of cooperative behavior is one of the most important and interesting problems in a myriad of disciplines, such as evolutionary biology, mathematics, statistical physics, social science and economics Up to now, there have been a great number of works aiming to this issue with the help of evolutionary game theory. However, vast majority of existing literatures simply assume that the interaction neighborhood and replacement neighborhood are symmetric, which seems inconsistent with real-world cases. In this paper, we consider the asymmetrical neighborhood: player of type A, whose factor is controlled by a parameter τ, has four interaction neighbors and four replacement neighbors, while player of type B, whose factor is controlled by a parameter 1 - τ, possess eight interaction neighbors and four replacement neighbors. By means of numerous Monte Carlo simulations, we found that middle τ can make the cooperation reach the highest level While for this finding, its robustness can be further validated in more games.

Efficient Wideband Spectrum Sensing with Maximal Spectral Efficiency for LEO Mobile Satellite Systems

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Feilong Li

2017-01-01

Full Text Available The usable satellite spectrum is becoming scarce due to static spectrum allocation policies. Cognitive radio approaches have already demonstrated their potential towards spectral efficiency for providing more spectrum access opportunities to secondary user (SU with sufficient protection to licensed primary user (PU. Hence, recent scientific literature has been focused on the tradeoff between spectrum reuse and PU protection within narrowband spectrum sensing (SS in terrestrial wireless sensing networks. However, those narrowband SS techniques investigated in the context of terrestrial CR may not be applicable for detecting wideband satellite signals. In this paper, we mainly investigate the problem of joint designing sensing time and hard fusion scheme to maximize SU spectral efficiency in the scenario of low earth orbit (LEO mobile satellite services based on wideband spectrum sensing. Compressed detection model is established to prove that there indeed exists one optimal sensing time achieving maximal spectral efficiency. Moreover, we propose novel wideband cooperative spectrum sensing (CSS framework where each SU reporting duration can be utilized for its following SU sensing. The sensing performance benefits from the novel CSS framework because the equivalent sensing time is extended by making full use of reporting slot. Furthermore, in respect of time-varying channel, the spatiotemporal CSS (ST-CSS is presented to attain space and time diversity gain simultaneously under hard decision fusion rule. Computer simulations show that the optimal sensing settings algorithm of joint optimization of sensing time, hard fusion rule and scheduling strategy achieves significant improvement in spectral efficiency. Additionally, the novel ST-CSS scheme performs much higher spectral efficiency than that of general CSS framework.

Effects of information asymmetry on cooperation in the prisoners' dilemma game

International Nuclear Information System (INIS)

Wang Xi-Peng; Wang Bing-Hong; Jiang Luo-Luo

2012-01-01

Effects of information asymmetry on cooperation in the prisoners' dilemma game are investigated. The amplitude A is introduced to describe the degree of information asymmetry. It is found that there exists an optimal value of amplitude A opt at which the fraction of cooperation reaches its maximal value. The reason lies in that cooperators on the two-dimensional grid form large clusters at A opt . In addition, the theoretical analysis in terms of the meanfield theory is used to understand this kind of phenomenon. It is confirmed that the information asymmetry plays an important role in the dynamics of the dilemma games of spatial prisoners. (general)

A spectrally efficient detect-and-forward scheme with two-tier adaptive cooperation

KAUST Repository

Benjillali, Mustapha; Szczeciński, Leszek L.; Alouini, Mohamed-Slim

2011-01-01

gainsin terms of the achievable information ratescompared to conventional DetF relaying schemes for both orthogonal and non-orthogonal source/relay transmissions. The analysis leads on to a general adaptive cooperation strategy based on the maximization

The Effectiveness of Cooperative Learning on the Reading Comprehension Skills in Turkish as a Foreign Language

Science.gov (United States)

Bolukbas, Fatma; Keskin, Funda; Polat, Mustafa

2011-01-01

Cooperative learning is a process through which students with various abilities, gender, nationalities and different level of social skills carry out their learning process by working in small groups and helping each other. Cooperative learning is a pedagogical use of small groups which enable students to maximize both their own and others'…

Attitudes of Economics and Sociology Students towards Cooperation. A Cross-Cultural Study

Directory of Open Access Journals (Sweden)

Joanna Dzionek-Kozlowska

2017-12-01

Full Text Available The impact of university education on the learners’ attitudes remains uncertain. Nevertheless, the Economics students’ unwillingness to cooperate is frequently attributed to the content of economic courses, and the theories of profit maximization. This article contributes to the discussion on students’ attitudes towards cooperation based on the survey of 341 Polish and Romanian students. Since these countries differ in terms of collectivism/individualism dimension, we focus on tracing the influence of cultures on cooperativeness. Specifically, we investigate three variables. First, the impact of culture on the willingness to cooperate, secondly, the influence of gender on collaboration, and finally, the differences in attitudes among the students of Sociology and Economics. We find significant differences between Polish and Romanian students’ attitudes towards cooperation, we also observe higher level cooperation among females than males. We detect a drop in cooperation from the first year to the subsequent years of undergraduate studies in Economics.

Diversity management in the workplace: beyond compliance

OpenAIRE

N.S. Gwele

2009-01-01

Diversity management is not a numbers game. Diversity management is a holistic and strategic intervention aimed at maximizing every individual’s potential to contribute towards the realization o f the organization’s goals through capitalizing on individual talents and differences within a diverse workforce environment. Managing interpersonal relationships within a diverse workforce environment presents a number of challenges related to changes in the social, legal and economic landscape, indi...

Essays on Cooperatives: Emergence, Retained Earnings, and Market Shares : Essays over coöperaties: Ontstaan, ingehouden winst en marktaandeel

NARCIS (Netherlands)

A. Petruchenya (Anna)

2018-01-01

markdownabstractCooperatives received significant attention in recent years as an alternative to investor-owned corporations. The objective of a cooperative to advance the interests of its member-owners is appealing from a societal perspective, particularly when comparing it with a profit-maximizing

A Novel Wireless Power Transfer-Based Weighed Clustering Cooperative Spectrum Sensing Method for Cognitive Sensor Networks.

Science.gov (United States)

Liu, Xin

2015-10-30

In a cognitive sensor network (CSN), the wastage of sensing time and energy is a challenge to cooperative spectrum sensing, when the number of cooperative cognitive nodes (CNs) becomes very large. In this paper, a novel wireless power transfer (WPT)-based weighed clustering cooperative spectrum sensing model is proposed, which divides all the CNs into several clusters, and then selects the most favorable CNs as the cluster heads and allows the common CNs to transfer the received radio frequency (RF) energy of the primary node (PN) to the cluster heads, in order to supply the electrical energy needed for sensing and cooperation. A joint resource optimization is formulated to maximize the spectrum access probability of the CSN, through jointly allocating sensing time and clustering number. According to the resource optimization results, a clustering algorithm is proposed. The simulation results have shown that compared to the traditional model, the cluster heads of the proposed model can achieve more transmission power and there exists optimal sensing time and clustering number to maximize the spectrum access probability.

A Novel Wireless Power Transfer-Based Weighed Clustering Cooperative Spectrum Sensing Method for Cognitive Sensor Networks

Directory of Open Access Journals (Sweden)

Xin Liu

2015-10-01

Full Text Available In a cognitive sensor network (CSN, the wastage of sensing time and energy is a challenge to cooperative spectrum sensing, when the number of cooperative cognitive nodes (CNs becomes very large. In this paper, a novel wireless power transfer (WPT-based weighed clustering cooperative spectrum sensing model is proposed, which divides all the CNs into several clusters, and then selects the most favorable CNs as the cluster heads and allows the common CNs to transfer the received radio frequency (RF energy of the primary node (PN to the cluster heads, in order to supply the electrical energy needed for sensing and cooperation. A joint resource optimization is formulated to maximize the spectrum access probability of the CSN, through jointly allocating sensing time and clustering number. According to the resource optimization results, a clustering algorithm is proposed. The simulation results have shown that compared to the traditional model, the cluster heads of the proposed model can achieve more transmission power and there exists optimal sensing time and clustering number to maximize the spectrum access probability.

Maximal Bell's inequality violation for non-maximal entanglement

International Nuclear Information System (INIS)

Kobayashi, M.; Khanna, F.; Mann, A.; Revzen, M.; Santana, A.

2004-01-01

Bell's inequality violation (BIQV) for correlations of polarization is studied for a product state of two two-mode squeezed vacuum (TMSV) states. The violation allowed is shown to attain its maximal limit for all values of the squeezing parameter, ζ. We show via an explicit example that a state whose entanglement is not maximal allow maximal BIQV. The Wigner function of the state is non-negative and the average value of either polarization is nil

Flouting maxim by sherlock holmes and dr. Watson in tv series Of sherlock season

Directory of Open Access Journals (Sweden)

Lina Affifatusholihah

2017-04-01

In running daily activities, people will always meet and interact with other people, and language is a medium that is used by humans to interact with each other. In a conversation or discussion, everyone should pay attention to the four maxims in order that there are no errors in communication. However, it is not uncommon that the four rules above are breached by the speakers. This is called non-observance of the maxims, and one of a non-observance of the maxims that often occurs in is flouting maxim. The aims of this paper are to describe types of maxims that are flouted by Sherlock Holmes and dr. Watson as well as to describe how the maxims are flouted in Sherlock TV series season 1. This research used qualitative descriptive method. The researcher classifies the utterances to know what kind of maxim which are flouted, categorizes those into the category based on the Grice’s theory of Cooperative Principle, namely: maxim of quantity, quality, relation and manner. The research procedure begin by searching the script in the internet, matching the utterances in the script and in film and sorting the utterances between Sherlock Holmes and dr. Watson as well observing every word or sentence which are flouted by the main characters. The findings find that all kinds of maxims are flouted by Sherlock and dr. Watson. The result of analysis shows that the maxim flouted when the speakers say something irrelevant; something roguishness or lied to hide the truth in the form of rhetorical question; the information becomes more or too informative than what is required; and something obscurity of expression, ambiguity, or unnecessary prolixity.

Robust Nash Dynamic Game Strategy for User Cooperation Energy Efficiency in Wireless Cellular Networks

Directory of Open Access Journals (Sweden)

Shuhuan Wen

2012-01-01

Full Text Available Recently, there is an emerging trend of addressing “energy efficiency” aspect of wireless communications. It has been shown that cooperating users relay each other's information to improve data rates. The energy is limited in the wireless cellular network, but the mobile users refuse to relay. This paper presents an approach that encourages user cooperation in order to improve the energy efficiency. The game theory is an efficient method to solve such conflicts. We present a cellular framework in which two mobile users, who desire to communicate with a common base station, may cooperate via decode-and-forward relaying. In the case of imperfect information assumption, cooperative Nash dynamic game is used between the two users' cooperation to tackle the decision making problems: whether to cooperate and how to cooperate in wireless networks. The scheme based on “cooperative game theory” can achieve general pareto-optimal performance for cooperative games, and thus, maximize the entire system payoff while maintaining fairness.

Social capital: its role in cooperation dilemmas and the coordination of actions

Directory of Open Access Journals (Sweden)

René Millán

2015-05-01

Full Text Available This work sustains the thesis that the concept of social capital must be understood as an element that helps to solve dilemmas of collective action. The concept is theoretically and in practice useful as it can be related to social cooperation problems. To sustain that statement, I present first the problem of cooperation as a dilemma between individual interest —or maximization strategies— and collective action. It is sustained that social capital confirms that, contrary to game theory, cooperate is rational and convenient. Then, it is established how it is conceived the relationship between social capital and cooperation in Coleman, Putnam and Ostrom. It is stressed the formation of incentives to overcome dilemmas of collective action. Finally, I develop a criticism to the critics made to social capital in order to establish its possibilities in generalizing social cooperation.

Cooperation schemes for rate enhancement in detect-and-forward relay channels

KAUST Repository

Benjillali, Mustapha

2010-05-01

To improve the spectral efficiency of "Detect-and-Forward" (DetF) half-duplex relaying in fading channels, we propose a cooperation scheme where the relay uses a modulation whose order is higher than the one at the source. In a new common framework, we show that the proposed scheme offers considerable gains - in terms of achievable information rates - compared to the conventional DetF relaying schemes for both orthogonal and non-orthogonal source/relay cooperation. This allows us to propose an adaptive cooperation scheme based on the maximization of the information rate at the destination which needs to observe only the average signal-to-noise ratios of direct and relaying links. ©2010 IEEE.

Impacts of extension access and cooperative membership on technology adoption and household welfare.

Science.gov (United States)

Wossen, Tesfamicheal; Abdoulaye, Tahirou; Alene, Arega; Haile, Mekbib G; Feleke, Shiferaw; Olanrewaju, Adetunji; Manyong, Victor

2017-08-01

This paper examines the impacts of access to extension services and cooperative membership on technology adoption, asset ownership and poverty using household-level data from rural Nigeria. Using different matching techniques and endogenous switching regression approach, we find that both extension access and cooperative membership have a positive and statistically significant effect on technology adoption and household welfare. Moreover, we find that both extension access and cooperative membership have heterogeneous impacts. In particular, we find evidence of a positive selection as the average treatment effects of extension access and cooperative membership are higher for farmers with the highest propensity to access extension and cooperative services. The impact of extension services on poverty reduction and of cooperatives on technology adoption is significantly stronger for smallholders with access to formal credit than for those without access. This implies that expanding rural financial markets can maximize the potential positive impacts of extension and cooperative services on farmers' productivity and welfare.

Maximizing and customer loyalty: Are maximizers less loyal?

Directory of Open Access Journals (Sweden)

Linda Lai

2011-06-01

Full Text Available Despite their efforts to choose the best of all available solutions, maximizers seem to be more inclined than satisficers to regret their choices and to experience post-decisional dissonance. Maximizers may therefore be expected to change their decisions more frequently and hence exhibit lower customer loyalty to providers of products and services compared to satisficers. Findings from the study reported here (N = 1978 support this prediction. Maximizers reported significantly higher intentions to switch to another service provider (television provider than satisficers. Maximizers' intentions to switch appear to be intensified and mediated by higher proneness to regret, increased desire to discuss relevant choices with others, higher levels of perceived knowledge of alternatives, and higher ego involvement in the end product, compared to satisficers. Opportunities for future research are suggested.

A coalition formation game for transmitter cooperation in OFDMA uplink communications

KAUST Repository

Chelli, Ali; Tembine, Hamidou; Alouini, Mohamed-Slim

2014-01-01

the nodes is modelled using coalitional game theory. In this game, each coalition tries to maximize its utility in terms of rate. In the absence of cooperation cost, it can be shown that the grand coalition is sum-rate optimal and stable, i.e., the mobile

Prosocial preferences do not explain human cooperation in public-goods games.

Science.gov (United States)

Burton-Chellew, Maxwell N; West, Stuart A

2013-01-02

It has become an accepted paradigm that humans have "prosocial preferences" that lead to higher levels of cooperation than those that would maximize their personal financial gain. However, the existence of prosocial preferences has been inferred post hoc from the results of economic games, rather than with direct experimental tests. Here, we test how behavior in a public-goods game is influenced by knowledge of the consequences of actions for other players. We found that (i) individuals cooperate at similar levels, even when they are not informed that their behavior benefits others; (ii) an increased awareness of how cooperation benefits others leads to a reduction, rather than an increase, in the level of cooperation; and (iii) cooperation can be either lower or higher than expected, depending on experimental design. Overall, these results contradict the suggested role of the prosocial preferences hypothesis and show how the complexity of human behavior can lead to misleading conclusions from controlled laboratory experiments.

Diversity as strategy.

Science.gov (United States)

Thomas, David A

2004-09-01

IBM's turnaround in the last decade is an impressive and well-documented business story. But behind that success is a less told people story, which explains how the corporation dramatically altered its already diverse composition and created millions of dollars in new business. By the time Lou Gerstner took the helm in 1993, IBM had a long history of progressive management when it came to civil rights and equal-opportunity employment. But Gerstner felt IBM wasn't taking full advantage of a diverse market for talent, nor was it maximizing the potential of its diverse customer and employee base. So in 1995, he launched a diversity task force initiative to uncover and understand differences among people within the organization and find ways to appeal to an even broader set of employees and customers. Gerstner established a task force for each of eight constituencies: Asians; blacks; the gay, lesbian, bisexual, transgendered community; Hispanics; white men; Native Americans; people with disabilities; and women. He asked the task forces to research four questions: What does your constituency need to feel welcome and valued at IBM? What can the corporation do, in partnership with your group, to maximize your constituency's productivity? What can the corporation do to influence your constituency's buying decisions so that IBM is seen as a preferred solution provider? And with which external organizations should IBM form relationships to better understand the needs of your constituency? The answers to these questions became the basis for IBM's diversity strategy. Thomas stresses that four factors are key to implementing any major change initiative: strong support from company leaders, an employee base that is fully engaged with the initiative, management practices that are integrated and aligned with the effort, and a strong and well-articulated business case for action. All four elements have helped IBM make diversity a key corporate strategy tied to real growth.

An Energy-Efficient Scheme for Multirelay Cooperative Networks with Energy Harvesting

Directory of Open Access Journals (Sweden)

Dingcheng Yang

2016-01-01

Full Text Available This study investigates an energy-efficient scheme in multirelay cooperative networks with energy harvesting where multiple sessions need to communicate with each other via the relay node. A two-step optimal method is proposed which maximizes the system energy efficiency, while taking into account the receiver circuit energy consumption. Firstly, the optimal power allocation for relay nodes is determined to maximize the system throughput; this is based on directional water-filling algorithm. Secondly, using quantum particle swarm optimization (QPSO, a joint relay node selection and session grouping optimization is proposed. With this algorithm, sessions can be classified into multiple groups that are assisted by the specific relay node with the maximum energy efficiency. This approach leads to a better global optimization in searching ability and efficiency. Simulation results show that the proposed scheme can improve the energy efficiency effectively compared with direct transmission and opportunistic relay-selected cooperative transmission.

Maximizing policy learning in international committees

DEFF Research Database (Denmark)

Nedergaard, Peter

2007-01-01

, this article demonstrates that valuable lessons can be learned about policy learning, in practice and theoretically, by analysing the cooperation in the OMC committees. Using the Advocacy Coalition Framework as the starting point of analysis, 15 hypotheses on policy learning are tested. Among other things......In the voluminous literature on the European Union's open method of coordination (OMC), no one has hitherto analysed on the basis of scholarly examination the question of what contributes to the learning processes in the OMC committees. On the basis of a questionnaire sent to all participants......, it is concluded that in order to maximize policy learning in international committees, empirical data should be made available to committees and provided by sources close to the participants (i.e. the Commission). In addition, the work in the committees should be made prestigious in order to attract well...

Cooperation: the foundation of improvement.

Science.gov (United States)

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.

Predicting Human Cooperation.

Directory of Open Access Journals (Sweden)

John J Nay

Full Text Available 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.

Effects of stand and inter-specific stocking on maximizing standing tree carbon stocks in the eastern United States

Science.gov (United States)

Christopher W. Woodall; Anthony W. D' Amato; John B. Bradford; Andrew O. Finley

2011-01-01

There is expanding interest in management strategies that maximize forest carbon (C) storage to mitigate increased atmospheric carbon dioxide. The tremendous tree species diversity and range of stand stocking found across the eastern United States presents a challenge for determining optimal combinations for the maximization of standing tree C storage. Using a...

Cooperation dynamics of generalized reciprocity in state-based social dilemmas

Science.gov (United States)

Stojkoski, Viktor; Utkovski, Zoran; Basnarkov, Lasko; Kocarev, Ljupco

2018-05-01

We introduce a framework for studying social dilemmas in networked societies where individuals follow a simple state-based behavioral mechanism based on generalized reciprocity, which is rooted in the principle "help anyone if helped by someone." Within this general framework, which applies to a wide range of social dilemmas including, among others, public goods, donation, and snowdrift games, we study the cooperation dynamics on a variety of complex network examples. By interpreting the studied model through the lenses of nonlinear dynamical systems, we show that cooperation through generalized reciprocity always emerges as the unique attractor in which the overall level of cooperation is maximized, while simultaneously exploitation of the participating individuals is prevented. The analysis elucidates the role of the network structure, here captured by a local centrality measure which uniquely quantifies the propensity of the network structure to cooperation by dictating the degree of cooperation displayed both at the microscopic and macroscopic level. We demonstrate the applicability of the analysis on a practical example by considering an interaction structure that couples a donation process with a public goods game.

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

Science.gov (United States)

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.

Comparison of the sensitivities of the Buehler test and the guinea pig maximization test for predictive testing of contact allergy

DEFF Research Database (Denmark)

Frankild, S; Vølund, A; Wahlberg, J E

2001-01-01

International test guidelines, such as the Organisation for Economic Cooperation and Development (OECD) guideline #406, recommend 2 guinea pig methods for testing of the contact allergenic potential of chemicals: the Guinea Pig Maximization Test (GPMT) and the Buehler test. Previous comparisons...

Partner Choice Drives the Evolution of Cooperation via Indirect Reciprocity.

Directory of Open Access Journals (Sweden)

Gilbert Roberts

Full Text Available Indirect reciprocity potentially provides an important means for generating cooperation based on helping those who help others. However, the use of 'image scores' to summarize individuals' past behaviour presents a dilemma: individuals withholding help from those of low image score harm their own reputation, yet giving to defectors erodes cooperation. Explaining how indirect reciprocity could evolve has therefore remained problematic. In all previous treatments of indirect reciprocity, individuals are assigned potential recipients and decide whether to cooperate or defect based on their reputation. A second way of achieving discrimination is through partner choice, which should enable individuals to avoid defectors. Here, I develop a model in which individuals choose to donate to anyone within their group, or to none. Whereas image scoring with random pairing produces cycles of cooperation and defection, with partner choice there is almost maximal cooperation. In contrast to image scoring with random pairing, partner choice results in almost perfect contingency, producing the correlation between giving and receiving required for cooperation. In this way, partner choice facilitates much higher and more stable levels of cooperation through image scoring than previously reported and provides a simple mechanism through which systems of helping those who help others can work.

The Perception of Cooperativeness Without Any Visual or Auditory Communication.

Science.gov (United States)

Chang, Dong-Seon; Burger, Franziska; Bülthoff, Heinrich H; de la Rosa, Stephan

2015-12-01

Perceiving social information such as the cooperativeness of another person is an important part of human interaction. But can people perceive the cooperativeness of others even without any visual or auditory information? In a novel experimental setup, we connected two people with a rope and made them accomplish a point-collecting task together while they could not see or hear each other. We observed a consistently emerging turn-taking behavior in the interactions and installed a confederate in a subsequent experiment who either minimized or maximized this behavior. Participants experienced this only through the haptic force-feedback of the rope and made evaluations about the confederate after each interaction. We found that perception of cooperativeness was significantly affected only by the manipulation of this turn-taking behavior. Gender- and size-related judgments also significantly differed. Our results suggest that people can perceive social information such as the cooperativeness of other people even in situations where possibilities for communication are minimal.

The Perception of Cooperativeness Without Any Visual or Auditory Communication

Directory of Open Access Journals (Sweden)

Dong-Seon Chang

2015-12-01

Full Text Available Perceiving social information such as the cooperativeness of another person is an important part of human interaction. But can people perceive the cooperativeness of others even without any visual or auditory information? In a novel experimental setup, we connected two people with a rope and made them accomplish a point-collecting task together while they could not see or hear each other. We observed a consistently emerging turn-taking behavior in the interactions and installed a confederate in a subsequent experiment who either minimized or maximized this behavior. Participants experienced this only through the haptic force-feedback of the rope and made evaluations about the confederate after each interaction. We found that perception of cooperativeness was significantly affected only by the manipulation of this turn-taking behavior. Gender- and size-related judgments also significantly differed. Our results suggest that people can perceive social information such as the cooperativeness of other people even in situations where possibilities for communication are minimal.

Energy-efficient power allocation of two-hop cooperative systems with imperfect channel estimation

KAUST Repository

Amin, Osama

2015-06-08

Recently, much attention has been paid to the green design of wireless communication systems using energy efficiency (EE) metrics that should capture all energy consumption sources to deliver the required data. In this paper, we formulate an accurate EE metric for cooperative two-hop systems that use the amplify-and-forward relaying scheme. Different from the existing research that assumes the availability of perfect channel state information (CSI) at the communication cooperative nodes, we assume a practical scenario, where training pilots are used to estimate the channels. The estimated CSI can be used to adapt the available resources of the proposed system in order to maximize the EE. Two estimation strategies are assumed namely disintegrated channel estimation, which assumes the availability of channel estimator at the relay, and cascaded channel estimation, where the relay is not equipped with channel estimator and only forwards the received pilot(s) in order to let the destination estimate the cooperative link. The channel estimation cost is reflected on the EE metric by including the estimation error in the signal-to-noise term and considering the energy consumption during the estimation phase. Based on the formulated EE metric, we propose an energy-aware power allocation algorithm to maximize the EE of the cooperative system with channel estimation. Furthermore, we study the impact of the estimation parameters on the optimized EE performance via simulation examples.

Impact of Base Station Cooperation on Cell Planning

Directory of Open Access Journals (Sweden)

Ian Dexter Garcia

2010-01-01

Full Text Available Base station cooperation (BSC has been identified as a key radio access technology for next-generation cellular networks such as LTE-Advanced. BSC impacts cell planning, which is the methodical selection of base station (BS sites, and BS equipment configuration for cost-effective cellular networks. In this paper, the impact of BSC on cell plan parameters (coverage, traffic, handover, and cost, as well as additional cell planning steps required for BSC are discussed. Results show that BSC maximizes its gains over noncooperation (NC in a network wherein interference from cooperating BSs is the main limitation. Locations exist where NC may produce higher throughputs, therefore dynamic or semistatic switching between BSC and NC, called fractional BSC, is recommended. Because of interference from noncooperating BSs, the gains of BSC over NC are upper bounded, and diminishes at greater intersite distances because of noise. This encourages smaller cell sizes, higher transmit powers, and dynamic clustering of cooperative BSs.

Human uniqueness-self-interest and social cooperation.

Science.gov (United States)

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.

Energy Security in Asia: Prospects for Regional Cooperation

OpenAIRE

Lucas, Nigel

2014-01-01

Three case studies illustrate some of the secondary consequences of the search for energy security and its relationship to regional trade and cooperation: the role of the People’s Republic of China, the emerging market in biofuels in Southeast Asia, and diverse feed-in tariffs for renewable energy. The three main ways regional cooperation can strengthen national policies on energy security are (i) sharing information and knowledge to create a sound evidence base for policies, (ii) agreeing on...

Interorganizational Knowledge Division Decision Model Based on Cooperative Innovation of Supply Chain System

Directory of Open Access Journals (Sweden)

Wei Zhang

2014-01-01

Full Text Available Within interorganizational cooperative innovation of construction supply chain system, the achievement of project value-adding could be reflected by several factors, such as project-based organizational effect level, and the relationship between project cooperative innovation objectives. In this paper, based on the assumption of equal cooperation between project-based organizations, we selected the knowledge cooperation between the owner and contractor in construction supply chain system as research object. From the perspective of maximizing project value-adding and the relationship of effort cost between knowledge input and innovation stage in consideration, we established the knowledge collaborative incentive model for interorganizational cooperative innovation of construction supply chain system and proposed the first-order and second-order approaches. Then we conducted the digital simulation and example analysis, its results showed that if the owner has the capability to achieve project value-adding in knowledge cooperation, he would adopt a part commissioned way. Otherwise, a fully commissioned way would be better.

Co-operation and Competition in Regional Economic Development Associated with Radioactive Waste Management

International Nuclear Information System (INIS)

Webler, Thomas

2009-01-01

Competition and co-operation appear in many different social venues. The author gives a variety of examples of co-operative behaviour in economics, politics, research, and everyday life activities such as sports. These four diverse examples illustrate the variety of forms that co-operation may take such as tacit co-operation, incremental co-operation, deep co-operation, etc. The links with the form of democracy (adversary democracy or consensual democracy) are also pointed. However, as with so many other things in life, the key is to the question of co-operation or competition is balance. Co-operation and competition are dialectical opposites. They create and maintain and define each other; they each are incomplete without the other

Principles of maximally classical and maximally realistic quantum ...

Indian Academy of Sciences (India)

Principles of maximally classical and maximally realistic quantum mechanics. S M ROY. Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400 005, India. Abstract. Recently Auberson, Mahoux, Roy and Singh have proved a long standing conjecture of Roy and Singh: In 2N-dimensional phase space, ...

Cooperation and defection at the crossroads.

Science.gov (United States)

Abramson, Guillermo; Semeshenko, Viktoriya; Iglesias, José Roberto

2013-01-01

We study a simple traffic model with a non-signalized road intersection. In this model the car arriving from the right has precedence. The vehicle dynamics far from the crossing are governed by the rules introduced by Nagel and Paczuski, which define how drivers behave when braking or accelerating. We measure the average velocity of the ensemble of cars and its flow as a function of the density of cars on the roadway. An additional set of rules is defined to describe the dynamics at the intersection assuming a fraction of drivers that do not obey the rule of precedence. This problem is treated within a game-theory framework, where the drivers that obey the rule are cooperators and those who ignore it are defectors. We study the consequences of these behaviors as a function of the fraction of cooperators and defectors. The results show that cooperation is the best strategy because it maximizes the flow of vehicles and minimizes the number of accidents. A rather paradoxical effect is observed: for any percentage of defectors the number of accidents is larger when the density of cars is low because of the higher average velocity.

Group penalty on the evolution of cooperation in spatial public goods games

International Nuclear Information System (INIS)

Zhang, Chunyan; Zhang, Jianlei; Xie, Guangming; Wang, Long

2010-01-01

We study the evolution of cooperation in spatial public goods games, whereby a coevolutionary rule is introduced that aims to integrate group penalty into the framework of evolutionary games. Existing groups are deleted whenever the collective gains of the focal individuals are less than a deletion threshold value. Meanwhile, newcomers are added after each game iteration to maintain the fixed population size. The networking effect is also studied via four representative interaction networks which are associated with the population structure. We conclude that the cooperation level has a strong dependence on the deletion threshold, and the suitable value range of the deletion threshold which is associated with the maximal cooperation frequency has been found. Simulation results also show that optimum values of the deletion threshold can still warrant the most potent promotion of cooperation, irrespective of which of the four topologies is applied

Profit maximization mitigates competition

DEFF Research Database (Denmark)

Dierker, Egbert; Grodal, Birgit

1996-01-01

We consider oligopolistic markets in which the notion of shareholders' utility is well-defined and compare the Bertrand-Nash equilibria in case of utility maximization with those under the usual profit maximization hypothesis. Our main result states that profit maximization leads to less price...... competition than utility maximization. Since profit maximization tends to raise prices, it may be regarded as beneficial for the owners as a whole. Moreover, if profit maximization is a good proxy for utility maximization, then there is no need for a general equilibrium analysis that takes the distribution...... of profits among consumers fully into account and partial equilibrium analysis suffices...

Implications of maximal Jarlskog invariant and maximal CP violation

International Nuclear Information System (INIS)

Rodriguez-Jauregui, E.; Universidad Nacional Autonoma de Mexico

2001-04-01

We argue here why CP violating phase Φ in the quark mixing matrix is maximal, that is, Φ=90 . In the Standard Model CP violation is related to the Jarlskog invariant J, which can be obtained from non commuting Hermitian mass matrices. In this article we derive the conditions to have Hermitian mass matrices which give maximal Jarlskog invariant J and maximal CP violating phase Φ. We find that all squared moduli of the quark mixing elements have a singular point when the CP violation phase Φ takes the value Φ=90 . This special feature of the Jarlskog invariant J and the quark mixing matrix is a clear and precise indication that CP violating Phase Φ is maximal in order to let nature treat democratically all of the quark mixing matrix moduli. (orig.)

Probabilistic interconnection between interdependent networks promotes cooperation in the public goods game

International Nuclear Information System (INIS)

Wang, Baokui; Chen, Xiaojie; Wang, Long

2012-01-01

Most previous works study the evolution of cooperation in a structured population by commonly employing an isolated single network. However, realistic systems are composed of many interdependent networks coupled with each other, rather than an isolated single one. In this paper, we consider a system including two interacting networks with the same size, entangled with each other by the introduction of probabilistic interconnections. We introduce the public goods game into such a system, and study how the probabilistic interconnection influences the evolution of cooperation of the whole system and the coupling effect between two layers of interdependent networks. Simulation results show that there exists an intermediate region of interconnection probability leading to the maximum cooperation level in the whole system. Interestingly, we find that at the optimal interconnection probability the fraction of internal links between cooperators in two layers is maximal. Also, even if initially there are no cooperators in one layer of interdependent networks, cooperation can still be promoted by probabilistic interconnection, and the cooperation levels in both layers can more easily reach an agreement at the intermediate interconnection probability. Our results may be helpful in understanding cooperative behavior in some realistic interdependent networks and thus highlight the importance of probabilistic interconnection on the evolution of cooperation. (paper)

Cooperative Detection for Primary User in Cognitive Radio Networks

Directory of Open Access Journals (Sweden)

Zhu Jia

2009-01-01

Full Text Available We propose two novel cooperative detection schemes based on the AF (Amplify and Forward and DF (Decode and Forward protocols to achieve spatial diversity gains for cognitive radio networks, which are referred to as the AF-CDS, (AF-based Cooperative Detection Scheme and DF-CDS (DF-based Cooperative Detection Scheme, respectively. Closed-form expressions of detection probabilities for the noncooperation scheme, AND-CDS (AND-based Cooperative Detection Scheme, AF-CDS and DF-CDS, are derived over Rayleigh fading channels. Also, we analyze the overall agility for the proposed cooperative detection schemes and show that our schemes can further reduce the detection time. In addition, we compare the DF-CDS with the AF-CDS in terms of detection probability and agility gain, depicting the advantage of DF-CDS at low SNR region and high false alarm probability region.

Cooperative HARQ Assisted NOMA Scheme in Large-scale D2D Networks

KAUST Repository

Shi, Zheng

2017-07-13

This paper develops an interference aware design for cooperative hybrid automatic repeat request (HARQ) assisted non-orthogonal multiple access (NOMA) scheme for large-scale device-to-device (D2D) networks. Specifically, interference aware rate selection and power allocation are considered to maximize long term average throughput (LTAT) and area spectral efficiency (ASE). The design framework is based on stochastic geometry that jointly accounts for the spatial interference correlation at the NOMA receivers as well as the temporal interference correlation across HARQ transmissions. It is found that ignoring the effect of the aggregate interference, or overlooking the spatial and temporal correlation in interference, highly overestimates the NOMA performance and produces misleading design insights. An interference oblivious selection for the power and/or transmission rates leads to violating the network outage constraints. To this end, the results demonstrate the effectiveness of NOMA transmission and manifest the importance of the cooperative HARQ to combat the negative effect of the network aggregate interference. For instance, comparing to the non-cooperative HARQ assisted NOMA, the proposed scheme can yield an outage probability reduction by $32$%. Furthermore, an interference aware optimal design that maximizes the LTAT given outage constraints leads to $47$% throughput improvement over HARQ-assisted orthogonal multiple access (OMA) scheme.

Formation Control of the MAXIM L2 Libration Orbit Mission

Science.gov (United States)

Folta, David; Hartman, Kate; Howell, Kathleen; Marchand, Belinda

2004-01-01

The Micro-Arcsecond X-ray Imaging Mission (MAXIM), a proposed concept for the Structure and Evolution of the Universe (SEU) Black Hole Imager mission, is designed to make a ten million-fold improvement in X-ray image clarity of celestial objects by providing better than 0.1 micro-arcsecond imaging. Currently the mission architecture comprises 25 spacecraft, 24 as optics modules and one as the detector, which will form sparse sub-apertures of a grazing incidence X-ray interferometer covering the 0.3-10 keV bandpass. This formation must allow for long duration continuous science observations and also for reconfiguration that permits re-pointing of the formation. To achieve these mission goals, the formation is required to cooperatively point at desired targets. Once pointed, the individual elements of the MAXIM formation must remain stable, maintaining their relative positions and attitudes below a critical threshold. These pointing and formation stability requirements impact the control and design of the formation. In this paper, we provide analysis of control efforts that are dependent upon the stability and the configuration and dimensions of the MAXIM formation. We emphasize the utilization of natural motions in the Lagrangian regions to minimize the control efforts and we address continuous control via input feedback linearization (IFL). Results provide control cost, configuration options, and capabilities as guidelines for the development of this complex mission.

Interlibrary cooperation: from ILL to IAIMS and beyond.

Science.gov (United States)

Riordan, M L; Perry, G J

1999-07-01

A recent solicitation over the MEDLIB-L e-mail discussion list revealed over thirty diverse examples of hospital library-based interlibrary cooperative initiatives currently underway. Many are familiar and have been featured in the professional literature. Most go unreported and unrecognized however, comprising invisible resource-sharing infrastructures that hospital librarians painstakingly piece together in order to provide their clients with expanded service options. This paper, drawing from the MEDLIB-L survey as well as descriptions in the published literature, provides a broad overview of such recent interlibrary cooperative efforts. Examples include interlibrary loan networks, collective purchasing initiatives, holder-of-record or union catalog access agreements, arrangements to provide e-mail and Internet access, and consortia to share electronic resources. Examples were chosen based on the initiatives' diversity of participants, and represent a wide range of locations across the United States. Such initiatives focus on local, statewide, or regional collaboration, and several involve partnerships between academic medical center libraries and regional hospital libraries. An early example of a hospital-based interlibrary cooperative IAIMS effort is described, pointing to future possibilities involving the Internet and regional hospital system intranets.

Capacity limits introduced by data fusion on cooperative spectrum sensing under correlated environments

DEFF Research Database (Denmark)

Pratas, Nuno; Marchetti, Nicola; Rodrigues, Antonio

2010-01-01

spectrum sensing scheme, by measuring the perceived capacity limits introduced by the use of data fusion on cooperative sensing schemes. The analysis is supported by evaluation metrics which account for the perceived capacity limits. The analysis is performed along the data fusion chain, comparing several...... scenarios encompassing different degree of environment correlation between the cluster nodes, number of cluster nodes and sensed channel occupation statistics. Through this study we motivate that to maximize the perceived capacity by the cooperative spectrum sensing, the use of data fusion needs...

Maximizers versus satisficers

Directory of Open Access Journals (Sweden)

Andrew M. Parker

2007-12-01

Full Text Available Our previous research suggests that people reporting a stronger desire to maximize obtain worse life outcomes (Bruine de Bruin et al., 2007. Here, we examine whether this finding may be explained by the decision-making styles of self-reported maximizers. Expanding on Schwartz et al. (2002, we find that self-reported maximizers are more likely to show problematic decision-making styles, as evidenced by self-reports of less behavioral coping, greater dependence on others when making decisions, more avoidance of decision making, and greater tendency to experience regret. Contrary to predictions, self-reported maximizers were more likely to report spontaneous decision making. However, the relationship between self-reported maximizing and worse life outcomes is largely unaffected by controls for measures of other decision-making styles, decision-making competence, and demographic variables.

A Power-Optimized Cooperative MAC Protocol for Lifetime Extension in Wireless Sensor Networks.

Science.gov (United States)

Liu, Kai; Wu, Shan; Huang, Bo; Liu, Feng; Xu, Zhen

2016-10-01

In wireless sensor networks, in order to satisfy the requirement of long working time of energy-limited nodes, we need to design an energy-efficient and lifetime-extended medium access control (MAC) protocol. In this paper, a node cooperation mechanism that one or multiple nodes with higher channel gain and sufficient residual energy help a sender relay its data packets to its recipient is employed to achieve this objective. We first propose a transmission power optimization algorithm to prolong network lifetime by optimizing the transmission powers of the sender and its cooperative nodes to maximize their minimum residual energy after their data packet transmissions. Based on it, we propose a corresponding power-optimized cooperative MAC protocol. A cooperative node contention mechanism is designed to ensure that the sender can effectively select a group of cooperative nodes with the lowest energy consumption and the best channel quality for cooperative transmissions, thus further improving the energy efficiency. Simulation results show that compared to typical MAC protocol with direct transmissions and energy-efficient cooperative MAC protocol, the proposed cooperative MAC protocol can efficiently improve the energy efficiency and extend the network lifetime.

Development of an International Electric Cooperative Initiative on Energy Efficiency

Energy Technology Data Exchange (ETDEWEB)

Paul Clark; David South

2004-05-01

NRECA conceived of the International Electric Cooperative Initiative on Energy Efficiency (IECIEE) in order to provide an ongoing means of contributing voluntary actions on greenhouse gas emissions mitigation as an integral component of its international programs and projects. This required designing the IECIEE to be integrated directly with the core interests and attributes of participating cooperatives in the U.S. and Latin America, which was the initial focus area selected for the IECIEE. In the case of NRECA International, the core interests related to promoting and strengthening the electric cooperative model, which has proved highly successful in maximizing operational efficiencies in electric power generation, distribution and retailing, as compared to government-owned entities. The approach involved three basic components: (i) establishing the IECIEE mechanism, which involved setting up a functioning organizational vehicle providing for investment, management, and emissions credit accounting; (ii) developing a portfolio of projects in countries where NRECA International could effectively implement the broader mandate of cooperative development as energy efficient suppliers and distributors of electrical energy; and (iii) conducting outreach to obtain the commitment of participants and resources from U.S. and Latin American cooperatives and partnering agencies in the development financing community.

Experimental Investigation of Cooperative Schemes on a Real-Time DSP-Based Testbed

Directory of Open Access Journals (Sweden)

Mavrokefalidis Christos

2009-01-01

Full Text Available Experimental results on the well-known cooperating relaying schemes, amplify-and-forward (AF, detect-and-forward (DF, cooperative maximum ratio combining (CMRC, and distributed space-time coding (DSTC, are presented in this paper. A novel relaying scheme named "selection relaying" (SR, in which one of two relays are selected base on path-loss, is also tested. For all schemes except AF receive antenna diversity is as an option which can be switched on or off. For DF and DSTC a feature "selective" where the relay only forwards frames with a receive SNR above 6 dB is introduced. In our measurements, all cooperative relaying schemes above increase the coverage area as compared with direct transmission. The features "antenna diversity" and "selective" improve the performance. Good performance is obtained with CMRC, DSTC, and SR.

An Energy Efficient Cooperative Hierarchical MIMO Clustering Scheme for Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

Sungyoung Lee

2011-12-01

Full Text Available In this work, we present an energy efficient hierarchical cooperative clustering scheme for wireless sensor networks. Communication cost is a crucial factor in depleting the energy of sensor nodes. In the proposed scheme, nodes cooperate to form clusters at each level of network hierarchy ensuring maximal coverage and minimal energy expenditure with relatively uniform distribution of load within the network. Performance is enhanced by cooperative multiple-input multiple-output (MIMO communication ensuring energy efficiency for WSN deployments over large geographical areas. We test our scheme using TOSSIM and compare the proposed scheme with cooperative multiple-input multiple-output (CMIMO clustering scheme and traditional multihop Single-Input-Single-Output (SISO routing approach. Performance is evaluated on the basis of number of clusters, number of hops, energy consumption and network lifetime. Experimental results show significant energy conservation and increase in network lifetime as compared to existing schemes.

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

Science.gov (United States)

Aktipis, C. Athena

2011-01-01

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. PMID:21666771

Interregional Cooperation Within Integration Processes in the Union State of Russia and Belarus

Directory of Open Access Journals (Sweden)

Ruslan Agarunovich Abramov

2016-12-01

Full Text Available The article deals with interregional cooperation of the Russian Federation and the Republic of Belarus in the spheres of trade, investment, industrial cooperation, education, science, culture, medicine and travel industry as a part of forming of The Eurasian Economic Space. Basing of the analysis of Russian and Belarusian regions’ experience the authors reveal the main problems of such cooperation. For example, it is shown that the major obstacle to making contacts between regions of the Union State is imperfection of federative and unitary structure, so there’s a need to enhance the role of supranational institutions and mechanisms for determining the interregional policy. It is proved that current contacts are geographically diversified. The authors give their recommendations to develop foundations for cooperation in innovative sector of economy. Identified prospects of development of interregional cooperation can be applied to the activities of legislative and executive authorities of the Union State as well as governmental bodies of Russian and Belarusian regions for maximizing their investment potential

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

Directory of Open Access Journals (Sweden)

Zhang Xing

2009-01-01

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

Developing maximal neuromuscular power: Part 1--biological basis of maximal power production.

Science.gov (United States)

Cormie, Prue; McGuigan, Michael R; Newton, Robert U

2011-01-01

This series of reviews focuses on the most important neuromuscular function in many sport performances, the ability to generate maximal muscular power. Part 1 focuses on the factors that affect maximal power production, while part 2, which will follow in a forthcoming edition of Sports Medicine, explores the practical application of these findings by reviewing the scientific literature relevant to the development of training programmes that most effectively enhance maximal power production. The ability of the neuromuscular system to generate maximal power is affected by a range of interrelated factors. Maximal muscular power is defined and limited by the force-velocity relationship and affected by the length-tension relationship. The ability to generate maximal power is influenced by the type of muscle action involved and, in particular, the time available to develop force, storage and utilization of elastic energy, interactions of contractile and elastic elements, potentiation of contractile and elastic filaments as well as stretch reflexes. Furthermore, maximal power production is influenced by morphological factors including fibre type contribution to whole muscle area, muscle architectural features and tendon properties as well as neural factors including motor unit recruitment, firing frequency, synchronization and inter-muscular coordination. In addition, acute changes in the muscle environment (i.e. alterations resulting from fatigue, changes in hormone milieu and muscle temperature) impact the ability to generate maximal power. Resistance training has been shown to impact each of these neuromuscular factors in quite specific ways. Therefore, an understanding of the biological basis of maximal power production is essential for developing training programmes that effectively enhance maximal power production in the human.

Evaluating β Diversity as a Surrogate for Species Representation at Fine Scale.

Directory of Open Access Journals (Sweden)

Paul Beier

Full Text Available Species turnover or β diversity is a conceptually attractive surrogate for conservation planning. However, there has been only 1 attempt to determine how well sites selected to maximize β diversity represent species, and that test was done at a scale too coarse (2,500 km2 sites to inform most conservation decisions. We used 8 plant datasets, 3 bird datasets, and 1 mammal dataset to evaluate whether sites selected to span β diversity will efficiently represent species at finer scale (sites sizes < 1 ha to 625 km2. We used ordinations to characterize dissimilarity in species assemblages (β diversity among plots (inventory data or among grid cells (atlas data. We then selected sites to maximize β diversity and used the Species Accumulation Index, SAI, to evaluate how efficiently the surrogate (selecting sites for maximum β diversity represented species in the same taxon. Across all 12 datasets, sites selected for maximum β diversity represented species with a median efficiency of 24% (i.e., the surrogate was 24% more effective than random selection of sites, and an interquartile range of 4% to 41% efficiency. β diversity was a better surrogate for bird datasets than for plant datasets, and for atlas datasets with 10-km to 14-km grid cells than for atlas datasets with 25-km grid cells. We conclude that β diversity is more than a mere descriptor of how species are distributed on the landscape; in particular β diversity might be useful to maximize the complementarity of a set of sites. Because we tested only within-taxon surrogacy, our results do not prove that β diversity is useful for conservation planning. But our results do justify further investigation to identify the circumstances in which β diversity performs well, and to evaluate it as a cross-taxon surrogate.

Translucent Players: Explaining Cooperative Behavior in Social Dilemmas

Directory of Open Access Journals (Sweden)

Valerio Capraro

2016-06-01

Full Text Available In the last few decades, numerous experiments have shown that humans do not always behave so as to maximize their material payoff. Cooperative behavior when non-cooperation is a dominant strategy (with respect to the material payoffs is particularly puzzling. Here we propose a novel approach to explain cooperation, assuming what Halpern and Pass call translucent players. Typically, players are assumed to be opaque, in the sense that a deviation by one player in a normal-form game does not affect the strategies used by other players. But a player may believe that if he switches from one strategy to another, the fact that he chooses to switch may be visible to the other players. For example, if he chooses to defect in Prisoner's Dilemma, the other player may sense his guilt. We show that by assuming translucent players, we can recover many of the regularities observed in human behavior in well-studied games such as Prisoner's Dilemma, Traveler's Dilemma, Bertrand Competition, and the Public Goods game.

A spectrally efficient detect-and-forward scheme with two-tier adaptive cooperation

KAUST Repository

Benjillali, Mustapha

2011-09-01

We propose a simple relay-based adaptive cooperation scheme to improve the spectral efficiency of "Detect-and-Forward" (DetF) half-duplex relaying in fading channels. In a new common framework, we show that the proposed scheme offers considerable gainsin terms of the achievable information ratescompared to conventional DetF relaying schemes for both orthogonal and non-orthogonal source/relay transmissions. The analysis leads on to a general adaptive cooperation strategy based on the maximization of information rates at the destination which needs to observe only the average signal-to-noise ratios of the links. © 2006 IEEE.

Managing diversity : How leaders' multiculturalism and colorblindness affect work group functioning

NARCIS (Netherlands)

Meeussen, Loes; Otten, Sabine; Phalet, Karen

Workforces are becoming increasingly diverse and leaders face the challenge of managing their groups to minimize costs and maximize benefits of diversity. This paper investigates how leaders' multiculturalism and colorblindness affect cultural minority and majority members' experiences of

Evolution of interactions and cooperation in the spatial prisoner's dilemma game.

Directory of Open Access Journals (Sweden)

Chunyan Zhang

Full Text Available We study the evolution of cooperation in the spatial prisoner's dilemma game where players are allowed to establish new interactions with others. By employing a simple coevolutionary rule entailing only two crucial parameters, we find that different selection criteria for the new interaction partners as well as their number vitally affect the outcome of the game. The resolution of the social dilemma is most probable if the selection favors more successful players and if their maximally attainable number is restricted. While the preferential selection of the best players promotes cooperation irrespective of game parametrization, the optimal number of new interactions depends somewhat on the temptation to defect. Our findings reveal that the "making of new friends" may be an important activity for the successful evolution of cooperation, but also that partners must be selected carefully and their number limited.

Microsatellite markers suggest high genetic diversity in an urban ...

Indian Academy of Sciences (India)

FRANCISCO MORINHA

diversity in an urban population of Cooper's hawks (Accipiter cooperii). J. Genet. 95, e19–e24. ... high quality habitat for this species (Boggie and Mannan. 2014) and the rapid ... The high densities of birds in urban populations can result in the ..... comparing urban and rural Cooper's hawk populations are mandatory to ...

Spatial prisoner's dilemma games with increasing neighborhood size and individual diversity on two interdependent lattices

Energy Technology Data Exchange (ETDEWEB)

Meng, Xiao-Kun [Tianjin Key Laboratory of Intelligence Computing and Novel Software Technology, Tianjin University of Technology, Tianjin 300384 (China); Key Laboratory of Computer Vision and System (Ministry of Education), Tianjin University of Technology, Tianjin 300384 (China); Xia, Cheng-Yi, E-mail: xialooking@163.com [Tianjin Key Laboratory of Intelligence Computing and Novel Software Technology, Tianjin University of Technology, Tianjin 300384 (China); Key Laboratory of Computer Vision and System (Ministry of Education), Tianjin University of Technology, Tianjin 300384 (China); Gao, Zhong-Ke [School of Electrical Engineering and Automation, Tianjin University, Tianjin 300072 (China); Wang, Li; Sun, Shi-Wen [Tianjin Key Laboratory of Intelligence Computing and Novel Software Technology, Tianjin University of Technology, Tianjin 300384 (China); Key Laboratory of Computer Vision and System (Ministry of Education), Tianjin University of Technology, Tianjin 300384 (China)

2015-04-03

Highlights: • A novel PDG model with individual diversity and utility interdependency is proposed. • Diversity can be represented by players with different strategy spreading abilities. • Interdependency is implemented by the payoff correlation between two lattices. • Cooperation can be remarkably promoted by combining these two kinds of mechanisms. - Abstract: We present an improved spatial prisoner's dilemma game model which simultaneously considers the individual diversity and increasing neighborhood size on two interdependent lattices. By dividing the players into influential and non-influential ones, we can discuss the impact of individual diversity on the cooperative behaviors. Meanwhile, we implement the utility interdependency by integrating the payoff correlations between two lattices. Extensive simulations indicate that the optimal density of influential players exists for the cooperation to be promoted, and can be further facilitated through the utility coupling. Current results are beneficial to understanding the origin of cooperation among selfish agents among realistic scenarios.

Spatial prisoner's dilemma games with increasing neighborhood size and individual diversity on two interdependent lattices

International Nuclear Information System (INIS)

Meng, Xiao-Kun; Xia, Cheng-Yi; Gao, Zhong-Ke; Wang, Li; Sun, Shi-Wen

2015-01-01

Highlights: • A novel PDG model with individual diversity and utility interdependency is proposed. • Diversity can be represented by players with different strategy spreading abilities. • Interdependency is implemented by the payoff correlation between two lattices. • Cooperation can be remarkably promoted by combining these two kinds of mechanisms. - Abstract: We present an improved spatial prisoner's dilemma game model which simultaneously considers the individual diversity and increasing neighborhood size on two interdependent lattices. By dividing the players into influential and non-influential ones, we can discuss the impact of individual diversity on the cooperative behaviors. Meanwhile, we implement the utility interdependency by integrating the payoff correlations between two lattices. Extensive simulations indicate that the optimal density of influential players exists for the cooperation to be promoted, and can be further facilitated through the utility coupling. Current results are beneficial to understanding the origin of cooperation among selfish agents among realistic scenarios

Throughput maximization for buffer-aided hybrid half-/full-duplex relaying with self-interference

KAUST Repository

Khafagy, Mohammad Galal

2015-06-01

In this work, we consider a two-hop cooperative setting where a source communicates with a destination through an intermediate relay node with a buffer. Unlike the existing body of work on buffer-aided half-duplex relaying, we consider a hybrid half-/full-duplex relaying scenario with loopback interference in the full-duplex mode. Depending on the channel outage and buffer states that are assumed available at the transmitters, the source and relay may either transmit simultaneously or revert to orthogonal transmission. Specifically, a joint source/relay scheduling and relaying mode selection mechanism is proposed to maximize the end-to-end throughput. The throughput maximization problem is converted to a linear program where the exact global optimal solution is efficiently obtained via standard convex/linear numerical optimization tools. Finally, the theoretical findings are corroborated with event-based simulations to provide the necessary performance validation.

Perception without self-matching in conditional tag based cooperation.

Science.gov (United States)

McAvity, David M; Bristow, Tristen; Bunker, Eric; Dreyer, Alex

2013-09-21

We consider a model for the evolution of cooperation in a population where individuals may have one of a number of different heritable and distinguishable markers or tags. Individuals interact with each of their neighbors on a square lattice by either cooperating by donating some benefit at a cost to themselves or defecting by doing nothing. The decision to cooperate or defect is contingent on each individual's perception of its interacting partner's tag. Unlike in other tag-based models individuals do not compare their own tag to that of their interaction partner. That is, there is no self-matching. When perception is perfect the cooperation rate is substantially higher than in the usual spatial prisoner's dilemma game when the cost of cooperation is high. The enhancement in cooperation is positively correlated with the number of different tags. The more diverse a population is the more cooperative it becomes. When individuals start with an inability to perceive tags the population evolves to a state where individuals gain at least partial perception. With some reproduction mechanisms perfect perception evolves, but with others the ability to perceive tags is imperfect. We find that perception of tags evolves to lower levels when the cost of cooperation is higher. Copyright © 2013 Elsevier Ltd. All rights reserved.

On the ARQ protocols over the Z-interference channels: Diversity-multiplexing-delay tradeoff

KAUST Repository

Nafea, Mohamed S.; Hamza, D.; Seddik, Karim G.; Nafie, Mohamed; Gamal, Hesham El

2012-01-01

We characterize the achievable three-dimensional tradeoff between diversity, multiplexing, and delay of the single antenna Automatic Retransmission reQuest (ARQ) Z-interference channel. Non-cooperative and cooperative ARQ protocols are adopted under

Divide and conquer: intermediate levels of population fragmentation maximize cultural accumulation.

Science.gov (United States)

Derex, Maxime; Perreault, Charles; Boyd, Robert

2018-04-05

Identifying the determinants of cumulative cultural evolution is a key issue in the interdisciplinary field of cultural evolution. A widely held view is that large and well-connected social networks facilitate cumulative cultural evolution because they promote the spread of useful cultural traits and prevent the loss of cultural knowledge through factors such as drift. This view stems from models that focus on the transmission of cultural information, without considering how new cultural traits actually arise. In this paper, we review the literature from various fields that suggest that, under some circumstances, increased connectedness can decrease cultural diversity and reduce innovation rates. Incorporating this idea into an agent-based model, we explore the effect of population fragmentation on cumulative culture and show that, for a given population size, there exists an intermediate level of population fragmentation that maximizes the rate of cumulative cultural evolution. This result is explained by the fact that fully connected, non-fragmented populations are able to maintain complex cultural traits but produce insufficient variation and so lack the cultural diversity required to produce highly complex cultural traits. Conversely, highly fragmented populations produce a variety of cultural traits but cannot maintain complex ones. In populations with intermediate levels of fragmentation, cultural loss and cultural diversity are balanced in a way that maximizes cultural complexity. Our results suggest that population structure needs to be taken into account when investigating the relationship between demography and cumulative culture.This article is part of the theme issue 'Bridging cultural gaps: interdisciplinary studies in human cultural evolution'. © 2018 The Author(s).

Maximizers versus satisficers

OpenAIRE

Andrew M. Parker; Wandi Bruine de Bruin; Baruch Fischhoff

2007-01-01

Our previous research suggests that people reporting a stronger desire to maximize obtain worse life outcomes (Bruine de Bruin et al., 2007). Here, we examine whether this finding may be explained by the decision-making styles of self-reported maximizers. Expanding on Schwartz et al. (2002), we find that self-reported maximizers are more likely to show problematic decision-making styles, as evidenced by self-reports of less behavioral coping, greater dependence on others when making decisions...

Cooperative heat transfer and ground coupled storage system

Science.gov (United States)

Metz, P.D.

A cooperative heat transfer and ground coupled storage system wherein collected solar heat energy is ground stored and permitted to radiate into the adjacent ground for storage therein over an extended period of time when such heat energy is seasonally maximally available. Thereafter, when said heat energy is seasonally minimally available and has propagated through the adjacent ground a substantial distance, the stored heat energy may be retrieved by a circumferentially arranged heat transfer means having a high rate of heat transfer.

Divergences in maximal supersymmetric Yang-Mills theories in diverse dimensions

International Nuclear Information System (INIS)

Bork, L.V.; Kazakov, D.I.; Kompaniets, M.V.; Tolkachev, D.M.; Vlasenko, D.E.

2015-01-01

The main aim of this paper is to study the scattering amplitudes in gauge field theories with maximal supersymmetry in dimensions D=6,8 and 10. We perform a systematic study of the leading ultraviolet divergences using the spinor helicity and on-shell momentum superspace framework. In D=6 the first divergences start at 3 loops and we calculate them up to 5 loops, in D=8,10 the first divergences start at 1 loop and we calculate them up to 4 loops. The leading divergences in a given order are the polynomials of Mandelstam variables. To be on the safe side, we check our analytical calculations by numerical ones applying the alpha-representation and the dedicated routines. Then we derive an analog of the RG equations for the leading pole that allows us to get the recursive relations and construct the generating procedure to obtain the polynomials at any order of perturbation theory (PT). At last, we make an attempt to sum the PT series and derive the differential equation for the infinite sum. This equation possesses a fixed point which might be stable or unstable depending on the kinematics. Some consequences of these fixed points are discussed.

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

Directory of Open Access Journals (Sweden)

Peng Lu

Full Text Available 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.

Neglecting the Maxim of Manner: How Readers Understand New Anglicisms Used in the Serbian Print Media

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Olga Panić-Kavgić

2017-06-01

Full Text Available The paper deals with the reception of new anglicisms by native speakers of Serbian, from semantic and pragmatic viewpoints, through theoretical and empirical observations. The main goal of the paper is to demonstrate to what extent and in what ways speakers understand anglicisms which they regularly encounter in Serbian daily newspapers and weekly magazines. It is through Grice's Cooperative Principle that the relationship between the journalist and the reader is examined and described. The conclusions are based on an analysis of the results of a large-scale research project conducted on a representative sample of native speakers who constitute the target readership of the selected newspapers and magazines. The research tool – an extensive written questionnaire – was created on the basis of a large corpus of anglicisms extracted from non-specialist daily and weekly press. The results of the analysis corroborate the initial hypothesis that there are varying degrees of noise in the communication channel between the journalist and reader, and that the journalist does not adhere to the Cooperative Principle. The way in which one of its maxims is regularly disregarded cannot fit into the existing classification and displays characteristics of a new category here termed ‘neglecting the maxim of manner’.

GENETIC DIVERSITY IN CZECH HAFLINGER HORSES

Directory of Open Access Journals (Sweden)

Luboš Vostrý

2015-09-01

Full Text Available The Haflinger as a small moutain horse breed originated from the South Tyrol district as a cross of Alpen Mountain breeds with Araber. This breed was expanding to Czech Republic during the last 25 years. The aim of this study was to analyse genetic diversity within the population using microsatellite markers. A total of 95 alleles have been detected. The highest frequency 88.18% showed allele 101 (HTG 6. The heterosigosity varied from 0.25 (HTG 6 to 0.84 (VHL 20, genetic diversity reached 0.6–0.8. The heterozygosity of the whole population studied is FIS= -0.013. The average effective number of allele per locus was 2.93 with standard deviation 1.54, with minimal and maximal level 1.30 and 7.83, respectively. Average polymorphism information content per locus was 0.608 with standard derivation 0.146, with minimal and maximal level 0.208 and 0.824, respectively. The results showed that breeding program of Czech Haflinger is optimal, including optimized mating strategies. The diversity of the population Czech Haflinger, based on a small number of microsatellites, seems to be sufficient.

Deciphering the Sox-Oct partner code by quantitative cooperativity measurements.

Science.gov (United States)

Ng, Calista K L; Li, Noel X; Chee, Sheena; Prabhakar, Shyam; Kolatkar, Prasanna R; Jauch, Ralf

2012-06-01

Several Sox-Oct transcription factor (TF) combinations have been shown to cooperate on diverse enhancers to determine cell fates. Here, we developed a method to quantify biochemically the Sox-Oct cooperation and assessed the pairing of the high-mobility group (HMG) domains of 11 Sox TFs with Oct4 on a series of composite DNA elements. This way, we clustered Sox proteins according to their dimerization preferences illustrating that Sox HMG domains evolved different propensities to cooperate with Oct4. Sox2, Sox14, Sox21 and Sox15 strongly cooperate on the canonical element but compete with Oct4 on a recently discovered compressed element. Sry also cooperates on the canonical element but binds additively to the compressed element. In contrast, Sox17 and Sox4 cooperate more strongly on the compressed than on the canonical element. Sox5 and Sox18 show some cooperation on both elements, whereas Sox8 and Sox9 compete on both elements. Testing rationally mutated Sox proteins combined with structural modeling highlights critical amino acids for differential Sox-Oct4 partnerships and demonstrates that the cooperativity correlates with the efficiency in producing induced pluripotent stem cells. Our results suggest selective Sox-Oct partnerships in genome regulation and provide a toolset to study protein cooperation on DNA.

On the ARQ protocols over the Z-interference channels: Diversity-multiplexing-delay tradeoff

KAUST Repository

Nafea, Mohamed S.

2012-07-01

We characterize the achievable three-dimensional tradeoff between diversity, multiplexing, and delay of the single antenna Automatic Retransmission reQuest (ARQ) Z-interference channel. Non-cooperative and cooperative ARQ protocols are adopted under these assumptions. Considering no cooperation exists, we study the achievable tradeoff of the fixed-power split Han-Kobayashi (HK) approach. Interestingly, we demonstrate that if the second user transmits the common part only of its message in the event of its successful decoding and a decoding failure at the first user, communication is improved over that achieved by keeping or stopping the transmission of both the common and private messages. Under cooperation, two special cases of the HK are considered for static and dynamic decoders. The difference between the two decoders lies in the ability of the latter to dynamically choose which HK special-case decoding to apply. Cooperation is shown to dramatically increase the achievable first user diversity. © 2012 IEEE.

Cooperative HARQ Assisted NOMA Scheme in Large-scale D2D Networks

KAUST Repository

Shi, Zheng; Ma, Shaodan; Elsawy, Hesham; Yang, Guanghua; Alouini, Mohamed-Slim

2017-01-01

spatial and temporal correlation in interference, highly overestimates the NOMA performance and produces misleading design insights. An interference oblivious selection for the power and/or transmission rates leads to violating the network outage constraints. To this end, the results demonstrate the effectiveness of NOMA transmission and manifest the importance of the cooperative HARQ to combat the negative effect of the network aggregate interference. For instance, comparing to the non-cooperative HARQ assisted NOMA, the proposed scheme can yield an outage probability reduction by $32$%. Furthermore, an interference aware optimal design that maximizes the LTAT given outage constraints leads to $47$% throughput improvement over HARQ-assisted orthogonal multiple access (OMA) scheme.

Diversity of Poissonian populations.

Science.gov (United States)

Eliazar, Iddo I; Sokolov, Igor M

2010-01-01

Populations represented by collections of points scattered randomly on the real line are ubiquitous in science and engineering. The statistical modeling of such populations leads naturally to Poissonian populations-Poisson processes on the real line with a distinguished maximal point. Poissonian populations are infinite objects underlying key issues in statistical physics, probability theory, and random fractals. Due to their infiniteness, measuring the diversity of Poissonian populations depends on the lower-bound cut-off applied. This research characterizes the classes of Poissonian populations whose diversities are invariant with respect to the cut-off level applied and establishes an elemental connection between these classes and extreme-value theory. The measures of diversity considered are variance and dispersion, Simpson's index and inverse participation ratio, Shannon's entropy and Rényi's entropy, and Gini's index.

[International cooperation at Public Health: proposals to a debate].

Science.gov (United States)

Loyola, Maria Andréa; Corrêa, Marilena Cordeiro Dias Villela; Guimarães, Eduardo Ribas De Biase

2010-07-01

In the available literature, there is no study devoted to international cooperation in public health. This paper aims to partly fill this gap, raising and examining the state of art in this area as well as how it interferes in the evaluation of post-graduate programs. The study used secondary data available at CAPES "Indicators Journals", during the years of 1998 to 2006. It also analyzes foreign scholarships and special programs of cooperation of CAPES from 2005 to 2009 through a quantitative descriptive methodology. It shows that international cooperation in the area is relatively developed in a variety of themes and diverse partnerships, focusing in the United States. It is observed a positive correlation between the number of international cooperation and a high-concept program into the evaluation of CAPES, the last triennium of evaluation. The sub-areas where there is more cooperation are, in order: epidemiology; planning, and others. There is a variety of institutions, themes and subareas involved in international cooperation that could be a positive indicator in the evaluation, but as far as was possible to infer, no significant correlation in this direction was found.

Working Capital Management of SriLakshminarayana Cooperative Urban Bank Ltd.,Tiruvarur

OpenAIRE

Nagarajapillai, Ramu

2007-01-01

In fact, under the new competitive pressures in Urban Cooperative Banks (UCBs) to enhance their overall efficiency pose serious challenges. Since the operational efficiency of the UCB is crucial in ensuring adequate and timely flow of credit to urban and semi-urban people for diverse purposes, intensive observation on their performance deserves serious consideration. In this context, present study examined management of resources of the Sri Lakshminarayana Cooperative Urban Bank Ltd. (SLNCUB)...

Entropy maximization

Indian Academy of Sciences (India)

Abstract. It is shown that (i) every probability density is the unique maximizer of relative entropy in an appropriate class and (ii) in the class of all pdf f that satisfy. ∫ fhi dμ = λi for i = 1, 2,...,...k the maximizer of entropy is an f0 that is pro- portional to exp(. ∑ ci hi ) for some choice of ci . An extension of this to a continuum of.

Promotion of technical cooperation in the field of energy

Energy Technology Data Exchange (ETDEWEB)

Yu, Jung Kyung; Jung, Duk Yung; Suh, Seong Seog; Park, Myung Nam; Kim, Young Mi; Cho, Moo Kyung [Korea Inst. of Energy Research, Taejon (Korea, Republic of)

1995-12-01

This study aims to improve the quality of human resources and the capability of research and development through the promotion of technical cooperation with foreign energy organizations possessing advanced technologies, and at the same time to contribute to internationalizing energy technology through the active involvement in multilateral technical cooperation programs with international organizations. To attain these aims, practical cooperative relations has been strengthened with 34 organizations from 11 countries including 6 organizations with which new cooperative agreements has been concluded in 1995 from the USA, Australia, China, and Russia, through the promotion of the continuous exchange of information and personnel, and international joint projects. And also the positive participation in technical cooperation programs and research projects organized or sponsored by APEC, IEA, UNDP, UNESCO, WEC has been made. In addition, for the improvement in research capability, 200 researchers has been dispatched abroad for the presentation of papers, of for the discussion of joint research projects, and 30 foreign experts through diverse overseas personnel exchange programs including Brain Pool Program were invited for the contribution of advancing research projects. (author). 8 figs., 15 tabs.

Multifaceted diversity-area relationships reveal global hotspots of mammalian species, trait and lineage diversity.

Science.gov (United States)

Mazel, Florent; Guilhaumon, François; Mouquet, Nicolas; Devictor, Vincent; Gravel, Dominique; Renaud, Julien; Cianciaruso, Marcus Vinicius; Loyola, Rafael Dias; Diniz-Filho, José Alexandre Felizola; Mouillot, David; Thuiller, Wilfried

2014-08-01

To define biome-scale hotspots of phylogenetic and functional mammalian biodiversity (PD and FD, respectively) and compare them to 'classical' hotspots based on species richness (SR) only. Global. SR, PD & FD were computed for 782 terrestrial ecoregions using distribution ranges of 4616 mammalian species. We used a set of comprehensive diversity indices unified by a recent framework that incorporates the species relative coverage in each ecoregion. We build large-scale multifaceted diversity-area relationships to rank ecoregions according to their levels of biodiversity while accounting for the effect of area on each diversity facet. Finally we defined hotspots as the top-ranked ecoregions. While ignoring species relative coverage led to a relative good congruence between biome top ranked SR, PD and FD hotspots, ecoregions harboring a rich and abundantly represented evolutionary history and functional diversity did not match with top ranked ecoregions defined by species richness. More importantly PD and FD hotspots showed important spatial mismatches. We also found that FD and PD generally reached their maximum values faster than species richness as a function of area. The fact that PD/FD reach faster their maximal value than SR may suggest that the two former facets might be less vulnerable to habitat loss than the latter. While this point is expected, it is the first time that it is quantified at global scale and should have important consequences in conservation. Incorporating species relative coverage into the delineation of multifaceted hotspots of diversity lead to weak congruence between SR, PD and FD hotspots. This means that maximizing species number may fail at preserving those nodes (in the phylogenetic or functional tree) that are relatively abundant in the ecoregion. As a consequence it may be of prime importance to adopt a multifaceted biodiversity perspective to inform conservation strategies at global scale.

A New Algorithm to Create Balanced Teams Promoting More Diversity

Science.gov (United States)

Dias, Teresa Galvão; Borges, José

2017-01-01

The problem of assigning students to teams can be described as maximising their profiles diversity within teams while minimising the differences among teams. This problem is commonly known as the maximally diverse grouping problem and it is usually formulated as maximising the sum of the pairwise distances among students within teams. We propose…

Entropy Maximization

Indian Academy of Sciences (India)

It is shown that (i) every probability density is the unique maximizer of relative entropy in an appropriate class and (ii) in the class of all pdf that satisfy ∫ f h i d = i for i = 1 , 2 , … , … k the maximizer of entropy is an f 0 that is proportional to exp ⁡ ( ∑ c i h i ) for some choice of c i . An extension of this to a continuum of ...

Carbon tariffs and cooperative outcomes

International Nuclear Information System (INIS)

Eyland, Terry; Zaccour, Georges

2014-01-01

In the absence of an international environmental agreement (IEA) on climate change, a country may be reluctant to unilaterally implement environmental actions, as this may lead to the relocation of firms to other, lax-on-pollution countries. To avoid this problem, while still taking care of the environment, a country may impose a carbon tariff that adjusts for the differences between its own carbon tax and the other country's tax. We consider two countries with a representative firm in each one, and characterize and contrast the equilibrium strategies and outcomes in three scenarios. In the first (benchmark) scenario, in a first stage the regulators in the two countries determine the carbon taxes noncooperatively, and in a second stage, the firms compete à la Cournot. In the second scenario, the regulators cooperate in determining the carbon taxes, while the firms still play a noncooperative Cournot game. In the third scenario, we add another player, e.g., the World Trade Organization, which announced a border tax in a prior stage; the game is then played as in the first scenario. Our two major results are (i) a border-tax adjustment (BTA) mimics quite well the cooperative solution in setting the carbon taxes as in scenario two. This means that a BTA may be a way around the lack of enthusiasm for an IEA. (ii) All of our simulations show that a partial correction of the difference in taxes is sufficient to maximize total welfare. In short, the conclusion is that a BTA may be used as a credible threat to achieve an outcome that is very close to the cooperative outcome. - Highlights: • One of the first studies to consider border-tax adjustment in a strategic context. • Border-tax adjustment can lead to an optimal outcome, in cooperative sense. • Optimal outcome is achieved with partial tax adjustment

Differences and implications in biogeochemistry from maximizing entropy production locally versus globally

Directory of Open Access Journals (Sweden)

J. J. Vallino

2011-06-01

Full Text Available In this manuscript we investigate the use of the maximum entropy production (MEP principle for modeling biogeochemical processes that are catalyzed by living systems. Because of novelties introduced by the MEP approach, many questions need to be answered and techniques developed in the application of MEP to describe biological systems that are responsible for energy and mass transformations on a planetary scale. In previous work we introduce the importance of integrating entropy production over time to distinguish abiotic from biotic processes under transient conditions. Here we investigate the ramifications of modeling biological systems involving one or more spatial dimensions. When modeling systems over space, entropy production can be maximized either locally at each point in space asynchronously or globally over the system domain synchronously. We use a simple two-box model inspired by two-layer ocean models to illustrate the differences in local versus global entropy maximization. Synthesis and oxidation of biological structure is modeled using two autocatalytic reactions that account for changes in community kinetics using a single parameter each. Our results show that entropy production can be increased if maximized over the system domain rather than locally, which has important implications regarding how biological systems organize and supports the hypothesis for multiple levels of selection and cooperation in biology for the dissipation of free energy.

Social norm complexity and past reputations in the evolution of cooperation.

Science.gov (United States)

Santos, Fernando P; Santos, Francisco C; Pacheco, Jorge M

2018-03-07

Indirect reciprocity is the most elaborate and cognitively demanding of all known cooperation mechanisms, and is the most specifically human because it involves reputation and status. By helping someone, individuals may increase their reputation, which may change the predisposition of others to help them in future. The revision of an individual's reputation depends on the social norms that establish what characterizes a good or bad action and thus provide a basis for morality. Norms based on indirect reciprocity are often sufficiently complex that an individual's ability to follow subjective rules becomes important, even in models that disregard the past reputations of individuals, and reduce reputations to either 'good' or 'bad' and actions to binary decisions. Here we include past reputations in such a model and identify the key pattern in the associated norms that promotes cooperation. Of the norms that comply with this pattern, the one that leads to maximal cooperation (greater than 90 per cent) with minimum complexity does not discriminate on the basis of past reputation; the relative performance of this norm is particularly evident when we consider a 'complexity cost' in the decision process. This combination of high cooperation and low complexity suggests that simple moral principles can elicit cooperation even in complex environments.

Maximally incompatible quantum observables

Energy Technology Data Exchange (ETDEWEB)

Heinosaari, Teiko, E-mail: teiko.heinosaari@utu.fi [Turku Centre for Quantum Physics, Department of Physics and Astronomy, University of Turku, FI-20014 Turku (Finland); Schultz, Jussi, E-mail: jussi.schultz@gmail.com [Dipartimento di Matematica, Politecnico di Milano, Piazza Leonardo da Vinci 32, I-20133 Milano (Italy); Toigo, Alessandro, E-mail: alessandro.toigo@polimi.it [Dipartimento di Matematica, Politecnico di Milano, Piazza Leonardo da Vinci 32, I-20133 Milano (Italy); Istituto Nazionale di Fisica Nucleare, Sezione di Milano, Via Celoria 16, I-20133 Milano (Italy); Ziman, Mario, E-mail: ziman@savba.sk [RCQI, Institute of Physics, Slovak Academy of Sciences, Dúbravská cesta 9, 84511 Bratislava (Slovakia); Faculty of Informatics, Masaryk University, Botanická 68a, 60200 Brno (Czech Republic)

2014-05-01

The existence of maximally incompatible quantum observables in the sense of a minimal joint measurability region is investigated. Employing the universal quantum cloning device it is argued that only infinite dimensional quantum systems can accommodate maximal incompatibility. It is then shown that two of the most common pairs of complementary observables (position and momentum; number and phase) are maximally incompatible.

Maximally incompatible quantum observables

International Nuclear Information System (INIS)

Heinosaari, Teiko; Schultz, Jussi; Toigo, Alessandro; Ziman, Mario

2014-01-01

The existence of maximally incompatible quantum observables in the sense of a minimal joint measurability region is investigated. Employing the universal quantum cloning device it is argued that only infinite dimensional quantum systems can accommodate maximal incompatibility. It is then shown that two of the most common pairs of complementary observables (position and momentum; number and phase) are maximally incompatible.

Link adaptation algorithm for distributed coded transmissions in cooperative OFDMA systems

DEFF Research Database (Denmark)

Varga, Mihaly; Badiu, Mihai Alin; Bota, Vasile

2015-01-01

This paper proposes a link adaptation algorithm for cooperative transmissions in the down-link connection of an OFDMA-based wireless system. The algorithm aims at maximizing the spectral efficiency of a relay-aided communication link, while satisfying the block error rate constraints at both...... adaptation algorithm has linear complexity with the number of available resource blocks, while still provides a very good performance, as shown by simulation results....

Trust as commodity: social value orientation affects the neural substrates of learning to cooperate.

Science.gov (United States)

Lambert, Bruno; Declerck, Carolyn H; Emonds, Griet; Boone, Christophe

2017-04-01

Individuals differ in their motives and strategies to cooperate in social dilemmas. These differences are reflected by an individual's social value orientation: proselfs are strategic and motivated to maximize self-interest, while prosocials are more trusting and value fairness. We hypothesize that when deciding whether or not to cooperate with a random member of a defined group, proselfs, more than prosocials, adapt their decisions based on past experiences: they 'learn' instrumentally to form a base-line expectation of reciprocity. We conducted an fMRI experiment where participants (19 proselfs and 19 prosocials) played 120 sequential prisoner's dilemmas against randomly selected, anonymous and returning partners who cooperated 60% of the time. Results indicate that cooperation levels increased over time, but that the rate of learning was steeper for proselfs than for prosocials. At the neural level, caudate and precuneus activation were more pronounced for proselfs relative to prosocials, indicating a stronger reliance on instrumental learning and self-referencing to update their trust in the cooperative strategy. © The Author (2017). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

A Low-Overhead Cooperative Retransmission Scheme for IR-UWB Networks

Directory of Open Access Journals (Sweden)

Ghasem Naddafzadeh Shirazi

2008-01-01

Full Text Available The UWB unique properties such as fine ranging and immunity to small scale fading are utilized in order to exploit the multiuser diversity in UWB networks. The optimal cooperation strategies in the absence of control packet overhead are analyzed in the proactive and reactive settings. It is shown that the proposed method achieves a considerable diversity gain while minimizing the overhead of control packet exchange that is required for coordination among the relays.

Working well in a culturally diverse team.

Science.gov (United States)

Day-Calder, Mandy

2016-10-05

Cooperative working is a core part of the nursing role, and it involves respecting your colleagues' needs and values. If you are part of a diverse team, you may need to develop your cultural competence, treating everyone compassionately and respectfully.

Maximum Lateness Scheduling on Two-Person Cooperative Games with Variable Processing Times and Common Due Date

Directory of Open Access Journals (Sweden)

Peng Liu

2017-01-01

Full Text Available A new maximum lateness scheduling model in which both cooperative games and variable processing times exist simultaneously is considered in this paper. The job variable processing time is described by an increasing or a decreasing function dependent on the position of a job in the sequence. Two persons have to cooperate in order to process a set of jobs. Each of them has a single machine and their processing cost is defined as the minimum value of maximum lateness. All jobs have a common due date. The objective is to maximize the multiplication of their rational positive cooperative profits. A division of those jobs should be negotiated to yield a reasonable cooperative profit allocation scheme acceptable to them. We propose the sufficient and necessary conditions for the problems to have positive integer solution.

Some common indices of group diversity: upper boundaries.

Science.gov (United States)

Solanas, Antonio; Selvam, Rejina M; Navarro, José; Leiva, David

2012-12-01

Workgroup diversity can be conceptualized as variety, separation, or disparity. Thus, the proper operationalization of diversity depends on how a diversity dimension has been defined. Analytically, the minimal diversity must be obtained when there are no differences on an attribute among the members of a group, however maximal diversity has a different shape for each conceptualization of diversity. Previous work on diversity indexes indicated maximum values for variety (e.g., Blau's index and Teachman's index), separation (e.g., standard deviation and mean Euclidean distance), and disparity (e.g., coefficient of variation and the Gini coefficient of concentration), although these maximum values are not valid for all group characteristics (i.e., group size and group size parity) and attribute scales (i.e., number of categories). We demonstrate analytically appropriate upper boundaries for conditional diversity determined by some specific group characteristics, avoiding the bias related to absolute diversity. This will allow applied researchers to make better interpretations regarding the relationship between group diversity and group outcomes.

Parochial cooperation in nested intergroup dilemmas is reduced when it harms out-groups.

Science.gov (United States)

Aaldering, Hillie; Ten Velden, Femke S; van Kleef, Gerben A; De Dreu, Carsten K W

2018-06-01

In intergroup settings, humans often contribute to their in-group at a personal cost. Such parochial cooperation benefits the in-group and creates and fuels intergroup conflict when it simultaneously hurts out-groups. Here, we introduce a new game paradigm in which individuals can display universal cooperation (which benefits both in- and out-group) as well as parochial cooperation that does, versus does not hurt the out-group. Using this set-up, we test hypotheses derived from group selection theory, social identity, and bounded generalized reciprocity theory. Across three experiments we find, first, that individuals choose parochial over universal cooperation. Second, there was no evidence for a motive to maximize differences between in- and out-group, which is central to both group selection and social identity theory. However, fitting bounded generalized reciprocity theory, we find that individuals with a prosocial value orientation display parochial cooperation, provided that this does not harm the out-group; individualists, in contrast, display parochialism whether or not nut it hurts the out-group. Our findings were insensitive to cognitive taxation (Experiments 2-3), and emerged even when universal cooperation served social welfare more than parochialism (Experiment 3). (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Maximal combustion temperature estimation

International Nuclear Information System (INIS)

Golodova, E; Shchepakina, E

2006-01-01

This work is concerned with the phenomenon of delayed loss of stability and the estimation of the maximal temperature of safe combustion. Using the qualitative theory of singular perturbations and canard techniques we determine the maximal temperature on the trajectories located in the transition region between the slow combustion regime and the explosive one. This approach is used to estimate the maximal temperature of safe combustion in multi-phase combustion models

Developing maximal neuromuscular power: part 2 - training considerations for improving maximal power production.

Science.gov (United States)

Cormie, Prue; McGuigan, Michael R; Newton, Robert U

2011-02-01

This series of reviews focuses on the most important neuromuscular function in many sport performances: the ability to generate maximal muscular power. Part 1, published in an earlier issue of Sports Medicine, focused on the factors that affect maximal power production while part 2 explores the practical application of these findings by reviewing the scientific literature relevant to the development of training programmes that most effectively enhance maximal power production. The ability to generate maximal power during complex motor skills is of paramount importance to successful athletic performance across many sports. A crucial issue faced by scientists and coaches is the development of effective and efficient training programmes that improve maximal power production in dynamic, multi-joint movements. Such training is referred to as 'power training' for the purposes of this review. Although further research is required in order to gain a deeper understanding of the optimal training techniques for maximizing power in complex, sports-specific movements and the precise mechanisms underlying adaptation, several key conclusions can be drawn from this review. First, a fundamental relationship exists between strength and power, which dictates that an individual cannot possess a high level of power without first being relatively strong. Thus, enhancing and maintaining maximal strength is essential when considering the long-term development of power. Second, consideration of movement pattern, load and velocity specificity is essential when designing power training programmes. Ballistic, plyometric and weightlifting exercises can be used effectively as primary exercises within a power training programme that enhances maximal power. The loads applied to these exercises will depend on the specific requirements of each particular sport and the type of movement being trained. The use of ballistic exercises with loads ranging from 0% to 50% of one-repetition maximum (1RM) and

Children's use of communicative intent in the selection of cooperative partners.

Directory of Open Access Journals (Sweden)

Kristen A Dunfield

Full Text Available Within the animal kingdom, human cooperation represents an outlier. As such, there has been great interest across a number of fields in identifying the factors that support the complex and flexible variety of cooperation that is uniquely human. The ability to identify and preferentially interact with better social partners (partner choice is proposed to be a major factor in maintaining costly cooperation between individuals. Here we show that the ability to engage in flexible and effective partner choice behavior can be traced back to early childhood. Specifically, across two studies, we demonstrate that by 3 years of age, children identify effective communication as "helpful" (Experiments 1 & 2, reward good communicators with information (Experiment 1, and selectively reciprocate communication with diverse cooperative acts (Experiment 2. Taken together, these results suggest that even in early childhood, humans take advantage of cooperative benefits, while mitigating free-rider risks, through appropriate partner choice behavior.

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

Science.gov (United States)

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. Copyright © 2015 Elsevier Inc. All rights reserved.

Lionfish predators use flared fin displays to initiate cooperative hunting.

Science.gov (United States)

Lönnstedt, Oona M; Ferrari, Maud C O; Chivers, Douglas P

2014-06-01

Despite considerable study, mystery surrounds the use of signals that initiate cooperative hunting in animals. Using a labyrinth test chamber, we examined whether a lionfish, Dendrochirus zebra, would initiate cooperative hunts with piscine partners. We found that D. zebra uses a stereotyped flared fin display to alert conspecific and heterospecific lionfish species Pterois antennata to the presence of prey. Per capita success rate was significantly higher for cooperative hunters when compared with solitary ones, with hunt responders assisting hunt initiators in cornering the prey using their large extended pectoral fins. The initiators would most often take the first strike at the group of prey, but both hunters would then alternate striking at the remaining prey. Results suggest that the cooperative communication signal may be characteristic to the lionfish family, as interspecific hunters were equally coordinated and successful as intraspecific hunters. Our findings emphasize the complexity of collaborative foraging behaviours in lionfish; the turn-taking in strikes suggests that individuals do not solely try to maximize their own hunting success: instead they equally share the resources between themselves. Communicative group hunting has enabled Pteroine fish to function as highly efficient predators. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

On the Usefulness of Cooperation in N Person Games

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Mikhail Sergeevich Nikolskii

2016-01-01

Full Text Available The N person games in which each player maximizes his payoff function are considered. We have studied an interesting question for the cooperative game theory about the usefulness of uniting the N players in a union. The aim of such cooperation is for each player to get a positive increase to his guaranteed payoff. We have obtained some effective sufficient conditions under which the joining of the players in union is useful for each player. The linear case, specially, is being considered. In the second part of the paper, we have studied the question about the usefulness of cooperation of the N players in the presence of the (N+1th player, an ill-intentioned destructive player, whose whole aim is not to win but to harm each player individually, and also the union of these players, for example, global terrorism. It should be noted that the considered situation in the second part is related to A. V. Kryazhimskiy’s talk delivered in the summer of 2014. We obtain constructive conditions under which the union of the players is beneficial in this situation as well.

Social penalty promotes cooperation in a cooperative society.

Science.gov (United States)

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.

Correlates of cooperation in a one-shot high-stakes televised prisoners' dilemma.

Directory of Open Access Journals (Sweden)

Maxwell N Burton-Chellew

Full Text Available Explaining cooperation between non-relatives is a puzzle for both evolutionary biology and the social sciences. In humans, cooperation is often studied in a laboratory setting using economic games such as the prisoners' dilemma. However, such experiments are sometimes criticized for being played for low stakes and by misrepresentative student samples. Golden balls is a televised game show that uses the prisoners' dilemma, with a diverse range of participants, often playing for very large stakes. We use this non-experimental dataset to investigate the factors that influence cooperation when "playing" for considerably larger stakes than found in economic experiments. The game show has earlier stages that allow for an analysis of lying and voting decisions. We found that contestants were sensitive to the stakes involved, cooperating less when the stakes were larger in both absolute and relative terms. We also found that older contestants were more likely to cooperate, that liars received less cooperative behavior, but only if they told a certain type of lie, and that physical contact was associated with reduced cooperation, whereas laughter and promises were reliable signals or cues of cooperation, but were not necessarily detected.

Knowledge collaborative incentive based on inter-organizational cooperative innovation of project-based supply chain

Directory of Open Access Journals (Sweden)

Guangdong Wu

2013-09-01

Full Text Available Purpose: Within project-based supply chain inter-organizational cooperative innovation, the achievement of project value-adding reflects by factors such as project-based organizational effect level, the relationship between project cooperative innovation objectives etc. The purpose is to provide a reliable reference for the contractor reasonably allocate the effect level and resources between the knowledge input and innovation stage and realize the knowledge collaboration for project-based supply chain. Design/methodology/approach: Based on the assumption of equal cooperation between project-based organizations, from the view of maximizing project value-adding and the relationship of effect cost between knowledge input and innovation stage in consideration, the knowledge collaborative incentive model for project-based supply chain inter-organizational cooperative innovation was established, and solved through the first-order and second-order approach, then the digital simulation and example analysis were presented. Findings: The results show that, the project management enterprise resorted to adjust project knowledge collaboration incentive intensity and implemented knowledge input-innovation coordinative incentive strategy, not only could achieve project value-adding maximization, but also could realize net earnings Pareto improvement between project management enterprise and contractor. Research limitations/implications: To simplify the knowledge flow among project-based organizations, the knowledge flow in the model hypothesis is presented as knowledge input and knowledge innovation stage, thus it may affect the final analysis results. Originality/value: In construction project practice, knowledge is become more and more important to achieve project value-adding. The research can provide a theoretical guideline for the project-based organizations, such as the contractor, the owner, especially how to utilize their core knowledge.

Maximizing work integration in job placement of individuals facing mental health problems: Supervisor experiences.

Science.gov (United States)

Skarpaas, Lisebet Skeie; Ramvi, Ellen; Løvereide, Lise; Aas, Randi Wågø

2015-01-01

Many people confronting mental health problems are excluded from participation in paid work. Supervisor engagement is essential for successful job placement. To elicit supervisor perspectives on the challenges involved in fostering integration to support individuals with mental health problems (trainees) in their job placement at ordinary companies. Explorative, qualitative designed study with a phenomenological approach, based on semi-structured interviews with 15 supervisors involved in job placements for a total of 105 trainees (mean 7, min-max. 1-30, SD 8). Data were analysed using qualitative content analysis. Superviors experience two interrelated dilemmas concerning knowledge of the trainee and degree of preferential treatment. Challenges to obtaining successful integration were; motivational: 1) Supervisors previous experience with trainees encourages future engagement, 2) Developing a realistic picture of the situation, and 3) Disclosure and knowledge of mental health problems, and continuity challenges: 4) Sustaining trainee cooperation throughout the placement process, 5) Building and maintaining a good relationship between supervisor and trainee, and 6) Ensuring continuous cooperation with the social security system and other stakeholders. Supervisors experience relational dilemmas regarding pre-judgment, privacy and equality. Job placement seem to be maximized when the stakeholders are motivated and recognize that cooperation must be a continuous process.

Multiuser hybrid switched-selection diversity systems

KAUST Repository

Shaqfeh, Mohammad

2011-09-01

A new multiuser scheduling scheme is proposed and analyzed in this paper. The proposed system combines features of conventional full-feedback selection-based diversity systems and reduced-feedback switch-based diversity systems. The new hybrid system provides flexibility in trading-off the channel information feedback overhead with the prospected multiuser diversity gains. The users are clustered into groups, and the users\\' groups are ordered into a sequence. Per-group feedback thresholds are used and optimized to maximize the system overall achievable rate. The proposed hybrid system applies switched diversity criterion to choose one of the groups, and a selection criterion to decide the user to be scheduled from the chosen group. Numerical results demonstrate that the system capacity increases as the number of users per group increases, but at the cost of more required feedback messages. © 2011 IEEE.

Understanding the diversity of cooperation on innovation across countries: multilevel evidence from Europe

Czech Academy of Sciences Publication Activity Database

Srholec, Martin

2015-01-01

Roč. 24, 1-2 (2015), s. 159-182 ISSN 1043-8599 R&D Projects: GA ČR GAP402/10/2310 Institutional support: RVO:67985998 Keywords : innovation * cooperation * multilevel model Subject RIV: AH - Economics

AUC-Maximizing Ensembles through Metalearning.

Science.gov (United States)

LeDell, Erin; van der Laan, Mark J; Petersen, Maya

2016-05-01

Area Under the ROC Curve (AUC) is often used to measure the performance of an estimator in binary classification problems. An AUC-maximizing classifier can have significant advantages in cases where ranking correctness is valued or if the outcome is rare. In a Super Learner ensemble, maximization of the AUC can be achieved by the use of an AUC-maximining metalearning algorithm. We discuss an implementation of an AUC-maximization technique that is formulated as a nonlinear optimization problem. We also evaluate the effectiveness of a large number of different nonlinear optimization algorithms to maximize the cross-validated AUC of the ensemble fit. The results provide evidence that AUC-maximizing metalearners can, and often do, out-perform non-AUC-maximizing metalearning methods, with respect to ensemble AUC. The results also demonstrate that as the level of imbalance in the training data increases, the Super Learner ensemble outperforms the top base algorithm by a larger degree.

Management Strategies in Multinational PricewaterhouseCoopers Romania

Directory of Open Access Journals (Sweden)

Norina Popovici

2011-05-01

Full Text Available This paper presents and analyzes the key strategies that underpin multinational firms acting in this global environment. The paper underlines the importance of strategy, in the current economic context, for a complex company such as PriceWaterhouse Coopers. After a laborious documentation, theoretical and practical, the paper presents the main strategic options which ensure the business development in the context of globalization. Due to complexity of work carried out by PricewaterhouseCoopers, due to a developed organizational structure and the large number of employees , the need for the strategy is " vital " for achieve the desired performance . In the past 10 years, PriceWaterhouse Coopers turned its global work on expanding the network size and diversity of services offered. Challenges and opportunities of today require a new strategic vision. Therefore, PriceWaterhouse Coopers calls for integrating the concept of sustainability as a management philosophy. In this context, which shapes the economy based on knowledge, management is a science which, through instruments such as corporate social responsibility, coaching procces, attracting talents, can help businesses to develop, diversify or to survive. The research of this company that led to the application of these tools work in Romanian companies, depending on the particular circumstances.

[Potential of cooperative learning in project development : Relevance of cooperative participation procedure for the further development of generation-appropriate accomodation in structurally weak rural areas].

Science.gov (United States)

Kaufmann, Gerd; Frankenberg, Olga; Sommer, Ralf-Rüdiger; Jost, Annemarie

2017-04-01

A joint initiative of existing senior care organizations, the municipality of Meyenburg and the state of Brandenburg was further developed by affiliation of an institute of the Brandenburg University of Technology Cottbus-Senftenberg (ABV) in cooperation with members of the architecture and social work departments in 2014. A cooperative process between different players was central to create an appropriate structure of services for this region. Cooperative projects are necessary to establish new forms of generation-appropriate living and care concepts in rural areas. Cooperative learning methods are needed to develop new forms of generation-appropriate living and care concepts in rural areas, which take the diversity of elderly people, the rural context, intergenerational residential arrangements and affordable accommodation that meets the requirements of the social security system into account. Furthermore, the project had to reflect the recent developments of the German care insurance. The article describes the participatory methods, the coordination process and the resulting concept.

International co-operation: a condition for further development of nuclear power

International Nuclear Information System (INIS)

Quenet, P.

1994-01-01

For two main reasons, loss of confidence in nuclear energy and loss of competitiveness, nuclear programmes are in recession, although the very high level of safety and reliability of NPP operation. Efficient co-operation among nuclear operators world wide in order to reach the highest possible standard everywhere. The mission of WANO is to maximize the safety and reliability of the operation of NPPs by exchanging information and encouraging comparison, emulation and communication among its members. (author)

Near-Optimal Resource Allocation in Cooperative Cellular Networks Using Genetic Algorithms

OpenAIRE

Luo, Zihan; Armour, Simon; McGeehan, Joe

2015-01-01

This paper shows how a genetic algorithm can be used as a method of obtaining the near-optimal solution of the resource block scheduling problem in a cooperative cellular network. An exhaustive search is initially implementedto guarantee that the optimal result, in terms of maximizing the bandwidth efficiency of the overall network, is found, and then the genetic algorithm with the properly selected termination conditions is used in the same network. The simulation results show that the genet...

On Building a Diverse Democracy: Justice and Identity in the Twenty-First Century

Science.gov (United States)

Patel, Eboo

2017-01-01

Passionate about making interfaith cooperation the social norm in a highly diverse religious world landscape, Eboo Patel is founder and president of Interfaith Youth Core. The organization brings together young people of different religious and moral traditions for cooperative service and dialogue around shared values. In this article, which is…

Is CP violation maximal

International Nuclear Information System (INIS)

Gronau, M.

1984-01-01

Two ambiguities are noted in the definition of the concept of maximal CP violation. The phase convention ambiguity is overcome by introducing a CP violating phase in the quark mixing matrix U which is invariant under rephasing transformations. The second ambiguity, related to the parametrization of U, is resolved by finding a single empirically viable definition of maximal CP violation when assuming that U does not single out one generation. Considerable improvement in the calculation of nonleptonic weak amplitudes is required to test the conjecture of maximal CP violation. 21 references

Shareholder, stakeholder-owner or broad stakeholder maximization

OpenAIRE

Mygind, Niels

2004-01-01

With reference to the discussion about shareholder versus stakeholder maximization it is argued that the normal type of maximization is in fact stakeholder-owner maxi-mization. This means maximization of the sum of the value of the shares and stake-holder benefits belonging to the dominating stakeholder-owner. Maximization of shareholder value is a special case of owner-maximization, and only under quite re-strictive assumptions shareholder maximization is larger or equal to stakeholder-owner...

Integrated Modeling of Solutions in the System of Distributing Logistics of a Fruit and Vegetable Cooperative

Directory of Open Access Journals (Sweden)

Oleksandr Velychko

2014-12-01

Full Text Available A mechanism of preparing rationalistic solutions in the system of distributing logistics of a fruit and vegetable cooperative has been studied considering possible alternatives and existing limitations. Belonging of separate operations of the fruit and vegetable cooperative to technological, logistical or marketing business processes has been identified. Expediency of the integrated use of logistical concept DRP, decision tree method and linear programming in management of the cooperative has been grounded. The model for preparing decisions on organizing sales of vegetables and fruit which is focused on minimization of costs of cooperative services and maximization of profits for members of the cooperation has been developed. The necessity to consider integrated model of differentiation on levels of post gathering processing and logistical service has been revealed. Methodology of representation in the economical-mathematical model of probabilities in the tree of decisions concerning the expected amount of sales and margin for members of the cooperative using different channels has been processed. A formula which enables scientists to describe limitations in linear programming concerning critical duration of providing harvest of vegetables and fruit after gathering towards a customer has been suggested.

Assessment of genetic diversity and variation of acer mono max seedlings after spaceflight

International Nuclear Information System (INIS)

Long, C.; Li, Y.; Zhang, Y.; Yang, M.

2015-01-01

Genetic diversity and variation of Acer Mono Maxim seedlings sampled from space-mutated (sm) populations were compared to seedlings from parallel control (ck) ones using molecular markers. RAMP analysis showed that the percentage of polymorphic band, Shannon diversity index and Nei gene diversity index of the space-mutated populations were higher than those of the control ones, which indicated that genetic variation increased after spaceflight in populations of Acer Mono Maxim. By using un-weighted pair group method with arithmetic mean (UPGMA) method, three space-mutated repeats (populations) were clustered together, and control groups clustered separately, which further indicated that there was difference between the space-mutated ones and the control ones, which may be caused by space mutation. Further analysis of genomic inconsistency between the root and leaf samples from the same tree showed that a total variation rate of 6.3% and 1.7% were obtained in ten space-mutated individuals by using RAMP and SSR markers, respectively, however, the variation rate was zero in control ones. It provided that space mutation may be caused the individual variation of Acer Mono Maxim. (author)

Numerical Simulations of Spread Characteristics of Toxic Cyanide in the Danjiangkou Reservoir in China under the Effects of Dam Cooperation

Directory of Open Access Journals (Sweden)

Libin Chen

2014-01-01

Full Text Available Many accidents of releasing toxic pollutants into surface water happen each year in the world. It is believed that dam cooperation can affect flow field in reservoir and then can be applied to avoiding and reducing spread speed of toxic pollutants to drinking water intake mouth. However, few studies investigated the effects of dam cooperation on the spread characteristics of toxic pollutants in reservoir, especially the source reservoir for water diversion with more than one dam. The Danjiangkou Reservoir is the source reservoir of the China’ South-to-North Water Diversion Middle Route Project. The human activities are active within this reservoir basin and cyanide-releasing accident once happened in upstream inflow. In order to simulate the spread characteristics of cyanide in the reservoir in the condition of dam cooperation, a three-dimensional water quality model based on the Environmental Fluid Dynamics Code (EFDC has been built and put into practice. The results indicated that cooperation of two dams of the Danjiangkou Reservoir could be applied to avoiding and reducing the spread speed of toxic cyanide in the reservoir directing to the water intake mouth for water diversions.

Task-oriented maximally entangled states

International Nuclear Information System (INIS)

Agrawal, Pankaj; Pradhan, B

2010-01-01

We introduce the notion of a task-oriented maximally entangled state (TMES). This notion depends on the task for which a quantum state is used as the resource. TMESs are the states that can be used to carry out the task maximally. This concept may be more useful than that of a general maximally entangled state in the case of a multipartite system. We illustrate this idea by giving an operational definition of maximally entangled states on the basis of communication tasks of teleportation and superdense coding. We also give examples and a procedure to obtain such TMESs for n-qubit systems.

Sixteen Years of International Co-operation. The OECD/NEA Co-operative Programme on Decommissioning

International Nuclear Information System (INIS)

Menon, S.; Valencia, L.

2002-01-01

The Co-operative Programme on Decommissioning under the administration of the Radioactive Waste Management Committee of the OECD Nuclear Energy Agency (NEA) has recently completed sixteen years of operation. The Programme, which is essentially an information exchange programme between decommissioning projects, came into being in 1985. It has grown from an initial 10 decommissioning projects from 7 countries to 39 projects from 14 countries today. From purely information exchange to start with, the Programme has, in later years, been functioning as a voice for the collective expression of views of the implementers of nuclear decommissioning. During the first sixteen years of the operation of the Co-operative Programme, nuclear decommissioning has grown from local specialist activities within projects to a competitive commercial industry. By the dismantling and release from regulatory control of over a dozen diverse nuclear facilities, the Programme has been able to demonstrate in practice, that nuclear decommissioning can be performed safely both for the workers and the public, and that this can be done at reasonable costs in an environmentally friendly fashion. During the recent years, discussions and work within the Co-operative Programme, specially within some of the Task Groups, have had/are having effects and repercussions not just in the field of nuclear decommissioning, but can possibly affect activities and regulations in other industries. This paper describes how the Programme and its activities and procedures have evolved over the years and indicate the directions of developments in the organization and execution of decommissioning projects. Finally, it gives a brief overview of the achievements of the Cooperative Programme and visualizes future developments in the field of nuclear decommissioning

Organizational structure and leadership styles in Savings and Credit Cooperatives of Pichincha

Directory of Open Access Journals (Sweden)

Sandra Patricia Galarza Torres

2017-07-01

Full Text Available Leadership studies are of great interest to organizations and management scientists, because of the diversity of theories and models that have been perfected over time. The objective of this research is to qualitatively determine the leadership styles used by the managers of the Savings and Credit Cooperatives of Pichincha province, and to relate them to the organizational structures through which these institutions operate. The methodology was based on the application of surveys to managers of 60 cooperatives, taking as reference the variables raised by Bass and Avolio in their "Multifactorial Questionnaire on MLQ Leadership" and the organizational structure was obtained by another methodologies. It is concluded that in the cooperatives studied the styles used by managers are: transactional, transformational and Laissez Faire, the latter being the predominant in the organizational structures of cooperatives.

Optimal Modality Selection for Cooperative Human-Robot Task Completion.

Science.gov (United States)

Jacob, Mithun George; Wachs, Juan P

2016-12-01

Human-robot cooperation in complex environments must be fast, accurate, and resilient. This requires efficient communication channels where robots need to assimilate information using a plethora of verbal and nonverbal modalities such as hand gestures, speech, and gaze. However, even though hybrid human-robot communication frameworks and multimodal communication have been studied, a systematic methodology for designing multimodal interfaces does not exist. This paper addresses the gap by proposing a novel methodology to generate multimodal lexicons which maximizes multiple performance metrics over a wide range of communication modalities (i.e., lexicons). The metrics are obtained through a mixture of simulation and real-world experiments. The methodology is tested in a surgical setting where a robot cooperates with a surgeon to complete a mock abdominal incision and closure task by delivering surgical instruments. Experimental results show that predicted optimal lexicons significantly outperform predicted suboptimal lexicons (p human-robot collision) and the differences in the lexicons are analyzed.

An interactive cooperation model for neighboring virtual power plants

International Nuclear Information System (INIS)

Shabanzadeh, Morteza; Sheikh-El-Eslami, Mohammad-Kazem; Haghifam, Mahmoud-Reza

2017-01-01

Highlights: •The trading strategies of a VPP in cooperation with its neighboring VPPs are addressed. •A portfolio of inter-regional contracts is considered to model this cooperation scheme. •A novel mathematical formulation for possible inadvertent transactions is provided. •A two-stage stochastic programming approach is applied to characterize the uncertainty. •Two efficient risk measures, SSD and CVaR, are implemented in the VPP decision-making problem. -- Abstract: Future distribution systems will accommodate an increasing share of distributed energy resources (DERs). Facing with this new reality, virtual power plants (VPPs) play a key role to aggregate DERs with the aim of facilitating their involvement in wholesale electricity markets. In this paper, the trading strategies of a VPP in cooperation with its neighboring VPPs are addressed. Toward this aim, a portfolio of inter-regional contracts is considered to model this cooperation and maximize the energy trade opportunities of the VPP within a medium-term horizon. To hedge against profit variability caused by market price uncertainties, two efficient risk management approaches are also implemented in the VPP decision-making problem based on the concepts of conditional value at risk (CVaR) and second-order stochastic dominance constraints (SSD). The resulting models are formulated as mixed-integer linear programming (MILP) problems that can be solved using off-the-shelf software packages. The efficiency of the proposed risk-hedging models is analyzed through a detailed case study, and thereby relevant conclusions are drawn.

Group size adjustment to ecological demand in a cooperative breeder.

Science.gov (United States)

Zöttl, Markus; Frommen, Joachim G; Taborsky, Michael

2013-04-07

Environmental factors can determine which group size will maximize the fitness of group members. This is particularly important in cooperative breeders, where group members often serve different purposes. Experimental studies are yet lacking to check whether ecologically mediated need for help will change the propensity of dominant group members to accept immigrants. Here, we manipulated the perceived risk of predation for dominant breeders of the cooperatively breeding cichlid fish Neolamprologus pulcher to test their response to unrelated and previously unknown immigrants. Potential immigrants were more readily accepted if groups were exposed to fish predators or egg predators than to herbivorous fish or control situations lacking predation risk. Our data are consistent with both risk dilution and helping effects. Egg predators were presented before spawning, which might suggest that the fish adjust acceptance rates also to a potential future threat. Dominant group members of N. pulcher apparently consider both present and future need of help based on ecological demand. This suggests that acceptance of immigrants and, more generally, tolerance of group members on demand could be a widespread response to ecological conditions in cooperatively breeding animals.

Complex Cooperative Strategies in Group-Territorial African Lions

Science.gov (United States)

Heinsohn, Robert; Packer, Craig

1995-09-01

Female lions (Panthera leo) showed persistent individual differences in the extent to which they participated in group-territorial conflict. When intergroup encounters were simulated by playback of aggressive vocalizations, some individuals consistently led the approach to the recorded intruder, whereas others lagged behind and avoided the risks of fighting. The lead females recognized that certain companions were laggards but failed to punish them, which suggests that cooperation is not maintained by reciprocity. Modification of the "odds" in these encounters revealed that some females joined the group response when they were most needed, whereas other lagged even farther behind. The complexity of these responses emphasizes the great diversity of individual behavior in this species and the inadequacy of current theory to explain cooperation in large groups.

VIOLATION OF CONVERSATION MAXIM ON TV ADVERTISEMENTS

Directory of Open Access Journals (Sweden)

Desak Putu Eka Pratiwi

2015-07-01

Full Text Available Maxim is a principle that must be obeyed by all participants textually and interpersonally in order to have a smooth communication process. Conversation maxim is divided into four namely maxim of quality, maxim of quantity, maxim of relevance, and maxim of manner of speaking. Violation of the maxim may occur in a conversation in which the information the speaker has is not delivered well to his speaking partner. Violation of the maxim in a conversation will result in an awkward impression. The example of violation is the given information that is redundant, untrue, irrelevant, or convoluted. Advertisers often deliberately violate the maxim to create unique and controversial advertisements. This study aims to examine the violation of maxims in conversations of TV ads. The source of data in this research is food advertisements aired on TV media. Documentation and observation methods are applied to obtain qualitative data. The theory used in this study is a maxim theory proposed by Grice (1975. The results of the data analysis are presented with informal method. The results of this study show an interesting fact that the violation of maxim in a conversation found in the advertisement exactly makes the advertisements very attractive and have a high value.

Finding Maximal Quasiperiodicities in Strings

DEFF Research Database (Denmark)

Brodal, Gerth Stølting; Pedersen, Christian N. S.

2000-01-01

of length n in time O(n log n) and space O(n). Our algorithm uses the suffix tree as the fundamental data structure combined with efficient methods for merging and performing multiple searches in search trees. Besides finding all maximal quasiperiodic substrings, our algorithm also marks the nodes......Apostolico and Ehrenfeucht defined the notion of a maximal quasiperiodic substring and gave an algorithm that finds all maximal quasiperiodic substrings in a string of length n in time O(n log2 n). In this paper we give an algorithm that finds all maximal quasiperiodic substrings in a string...... in the suffix tree that have a superprimitive path-label....

Can Higher Education Meet the Needs of an Increasingly Diverse and Global Society? Campus Diversity and Cross-Cultural Workforce Competencies

Science.gov (United States)

Jayakumar, Uma M.

2008-01-01

In this article, Uma Jayakumar investigates the relationship between white individuals' exposure to racial diversity during college and their postcollege cross-cultural workforce competencies. Using survey data from the Cooperative Institutional Research Program, housed in the Higher Education Research Institute at the University of California at…

The intermediate disturbance hypothesis applies to tropical forests, but disturbance contributes little to tree diversity

NARCIS (Netherlands)

Bongers, F.; Poorter, L.; Hawthorne, W.D.; Sheil, D.

2009-01-01

The intermediate disturbance hypothesis (IDH) predicts local species diversity to be maximal at an intermediate level of disturbance. Developed to explain species maintenance and diversity patterns in species-rich ecosystems such as tropical forests, tests of IDH in tropical forest remain scarce,

Enhanced Cooperation - the New Trend of the EU Development

Directory of Open Access Journals (Sweden)

Lyudmila O. Babynina

2014-01-01

Full Text Available The article is dedicated to implementation of the enhanced cooperation in the EU. Actually two such projects are шn progress (the law applicable to divorce and legal separation and unitary patent protection and other two are under discussionffmandai transaction tax and European Public Prosecutor's Office. Active use of the enhanced cooperation recently shows that such kind of the promoting integration is more and more required in the EU. However its implementation can jeopardize the principles of the EU functioning and undermine the status of the institutions in the integration process. This mechanism can also be used in order to exclude the discordant states from integration process instead of traditional search of compromises. This argument is based on analysis of the implementation conditions of the project on the unitary patent protection. At the same time the projects of the enhanced cooperation obviously make the interaction in different spheres more efficient. In addition they can be used for testing the new types of cooperation. That's why the search for an optimal balance between promotion integration through the mechanism of enhanced cooperation and preserving the unity of the EU should be considered as main goal by participants of the integration process. Otherwise the gradual separation on the vanguard group may lead to EU division. Nevertheless taking into consideration enlargement of the EU and its diversity, the enhanced cooperation Should be used onlyas "extreme measure".

Shareholder, stakeholder-owner or broad stakeholder maximization

DEFF Research Database (Denmark)

Mygind, Niels

2004-01-01

With reference to the discussion about shareholder versus stakeholder maximization it is argued that the normal type of maximization is in fact stakeholder-owner maxi-mization. This means maximization of the sum of the value of the shares and stake-holder benefits belonging to the dominating...... including the shareholders of a company. Although it may be the ultimate goal for Corporate Social Responsibility to achieve this kind of maximization, broad stakeholder maximization is quite difficult to give a precise definition. There is no one-dimensional measure to add different stakeholder benefits...... not traded on the mar-ket, and therefore there is no possibility for practical application. Broad stakeholder maximization instead in practical applications becomes satisfying certain stakeholder demands, so that the practical application will be stakeholder-owner maximization un-der constraints defined...

On the maximal superalgebras of supersymmetric backgrounds

International Nuclear Information System (INIS)

Figueroa-O'Farrill, Jose; Hackett-Jones, Emily; Moutsopoulos, George; Simon, Joan

2009-01-01

In this paper we give a precise definition of the notion of a maximal superalgebra of certain types of supersymmetric supergravity backgrounds, including the Freund-Rubin backgrounds, and propose a geometric construction extending the well-known construction of its Killing superalgebra. We determine the structure of maximal Lie superalgebras and show that there is a finite number of isomorphism classes, all related via contractions from an orthosymplectic Lie superalgebra. We use the structure theory to show that maximally supersymmetric waves do not possess such a maximal superalgebra, but that the maximally supersymmetric Freund-Rubin backgrounds do. We perform the explicit geometric construction of the maximal superalgebra of AdS 4 X S 7 and find that it is isomorphic to osp(1|32). We propose an algebraic construction of the maximal superalgebra of any background asymptotic to AdS 4 X S 7 and we test this proposal by computing the maximal superalgebra of the M2-brane in its two maximally supersymmetric limits, finding agreement.

Stakeholder cooperation in implementation of the sustainable development concept: Montenegrin tourist destinations

Directory of Open Access Journals (Sweden)

Ljiljana Pjerotic

2017-06-01

Full Text Available The importance of involving diverse stakeholders in tourism planning is receiving growing recognition. Tourism destination planning is a complex process, due to the existence of a wide variety of stakeholders with a wide range of opinions, multiple problem visions and different interests. Despite the complexity of the planning process one feature acknowledged for successful destination management planning is high level of stakeholder cooperation. The paper examines the level of stakeholder cooperation on the specific example of the sustainable development concept implementation in Montenegrin tourism. It starts with two hypotheses: first, the development level of instruments for managing tourist destination depends on stakeholder cooperation level in a particular destination, and second, implementation of the sustainable development concept is positively correlated with the development of instruments for managing tourist destination. The results have indicated poor implementation of tourism development plans and low level of stakeholder cooperation.

To cooperate or not to cooperate

DEFF Research Database (Denmark)

Wessels, Josepha Ivanka

To Cooperate or not to Cooperate...? discusses results of a research project to study the rehabilitation of 1500-year old water tunnels, so called "qanats", in Syria. Communities all over the world are using traditional technologies to extract drinkingwater, irrigate their lands and feed...... their livestock. But these often sustainable and ancient ways to make use of groundwater are in rapid decline worldwide. A research project started in 1999 to study the rehabilitation of 1500-year old water tunnels called "qanats"in Syria. To Cooperate or not to Cooperate...? discusses results and outcomes...

Cultural diversity and work-group performance : Detecting the rules

NARCIS (Netherlands)

Girndt, T.

2000-01-01

With greater levels of international cooperation, work-groups are increasingly composed of members from different cultures. These groups often suffer from communication problems; however, research suggests that they also benefit from their members cultural diversity and generate higher ranges of

International pollution control: Cooperative versus noncooperative strategies

International Nuclear Information System (INIS)

Dockner, E.J.; Van Long, N.

1993-01-01

International pollution control involving two neighboring countries is modeled as a simple two-player dynamic game. Each country produces a good that is consumed by domestic households. Production of each consumption good results in emissions of pollutants. Households in each country derive utility from the consumption of the domestically produced good but incur costs through the total stock of pollution (stock externality). In this setting we characterize cooperative as well as noncooperative pollution control strategies of the governments of the two countries that maximize the discounted stream of net benefits of a representative consumer. It turns out that when the governments are restricted to use linear strategies noncooperative behavior results in overall losses for both countries. If, on the contrary, governments use nonlinear Markov-perfect strategies and the discount rate is small enough a Pareto-efficient steady-state pollution stock can be supported as a differentiable subgame-perfect equilibrium. Thus, the emergence of first-best solutions (cooperative outcomes) does not require any institutional arrangements (threats, retaliation, etc.) but can be brought about through the use of nonlinear Markov-perfect equilibrium strategies. 20 refs., 1 tab

A game theoretical approach for cooperative environmentally friendly cellular networks powered by the smart grid

KAUST Repository

Ghazzai, Hakim

2014-11-01

This paper investigates the collaboration between multiple mobile operators to optimize the energy efficiency of cellular networks, maximize their profits or achieve or tradeoff between both objectives. Mobile operators cooperate together by eliminating redundant base stations (BSs) using a low complexity algorithm that aims to maximize their objective functions subject to a quality of service constraint. The problem is modeled as a two-level Stackelberg game: a mobile operator level and a smart grid level. Indeed, in our framework, we assume that cellular networks are powered by multiple energy providers existing in the smart grid characterized by different pollutant levels in addition to renewable energy source deployed in BS sites. The objective is to find the best active BS combination and the optimal procurement decision needed to the network operation during collaboration by considering electricity real-time pricing. Our study includes the daily traffic variation in addition to the daily green energy availability. Our simulation results show a significant saving in terms of CO2 emissions compared to the non-collaboration case and that cooperative mobile operators exploiting renewables are more awarded than traditional operators. © 2014 IEEE.

Maximally multipartite entangled states

Science.gov (United States)

Facchi, Paolo; Florio, Giuseppe; Parisi, Giorgio; Pascazio, Saverio

2008-06-01

We introduce the notion of maximally multipartite entangled states of n qubits as a generalization of the bipartite case. These pure states have a bipartite entanglement that does not depend on the bipartition and is maximal for all possible bipartitions. They are solutions of a minimization problem. Examples for small n are investigated, both analytically and numerically.

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

Science.gov (United States)

2010-03-05

... DEPARTMENT OF LABOR Employment and Training Administration [TA-W-71,602] Cooper Tools--Sumter, Cooper Tools Divisions, a Subsidiary of Cooper Industries, Inc., Including On-Site Leased Workers From... January 26, 2010, applicable to workers of Cooper Tools--Sumter, Cooper Tools Division, a subsidiary of...

Maximally Symmetric Composite Higgs Models.

Science.gov (United States)

Csáki, Csaba; Ma, Teng; Shu, Jing

2017-09-29

Maximal symmetry is a novel tool for composite pseudo Goldstone boson Higgs models: it is a remnant of an enhanced global symmetry of the composite fermion sector involving a twisting with the Higgs field. Maximal symmetry has far-reaching consequences: it ensures that the Higgs potential is finite and fully calculable, and also minimizes the tuning. We present a detailed analysis of the maximally symmetric SO(5)/SO(4) model and comment on its observational consequences.

The coevolution of long-term pair bonds and cooperation.

Science.gov (United States)

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. © 2013 The Authors. Journal of Evolutionary Biology © 2013 European Society For Evolutionary Biology.

Maximal quantum Fisher information matrix

International Nuclear Information System (INIS)

Chen, Yu; Yuan, Haidong

2017-01-01

We study the existence of the maximal quantum Fisher information matrix in the multi-parameter quantum estimation, which bounds the ultimate precision limit. We show that when the maximal quantum Fisher information matrix exists, it can be directly obtained from the underlying dynamics. Examples are then provided to demonstrate the usefulness of the maximal quantum Fisher information matrix by deriving various trade-off relations in multi-parameter quantum estimation and obtaining the bounds for the scalings of the precision limit. (paper)

Understanding Violations of Gricean Maxims in Preschoolers and Adults

Directory of Open Access Journals (Sweden)

Mako eOkanda

2015-07-01

Full Text Available This study used a revised Conversational Violations Test to examine Gricean maxim violations in 4- to 6-year-old Japanese children and adults. Participants’ understanding of the following maxims was assessed: be informative (first maxim of quantity, avoid redundancy (second maxim of quantity, be truthful (maxim of quality, be relevant (maxim of relation, avoid ambiguity (second maxim of manner, and be polite (maxim of politeness. Sensitivity to violations of Gricean maxims increased with age: 4-year-olds’ understanding of maxims was near chance, 5-year-olds understood some maxims (first maxim of quantity and maxims of quality, relation, and manner, and 6-year-olds and adults understood all maxims. Preschoolers acquired the maxim of relation first and had the greatest difficulty understanding the second maxim of quantity. Children and adults differed in their comprehension of the maxim of politeness. The development of the pragmatic understanding of Gricean maxims and implications for the construction of developmental tasks from early childhood to adulthood are discussed.

A cooperative reduction model for regional air pollution control in China that considers adverse health effects and pollutant reduction costs.

Science.gov (United States)

Xie, Yujing; Zhao, Laijun; Xue, Jian; Hu, Qingmi; Xu, Xiang; Wang, Hongbo

2016-12-15

How to effectively control severe regional air pollution has become a focus of global concern recently. The non-cooperative reduction model (NCRM) is still the main air pollution control pattern in China, but it is both ineffective and costly, because each province must independently fight air pollution. Thus, we proposed a cooperative reduction model (CRM), with the goal of maximizing the reduction in adverse health effects (AHEs) at the lowest cost by encouraging neighboring areas to jointly control air pollution. CRM has two parts: a model of optimal pollutant removal rates using two optimization objectives (maximizing the reduction in AHEs and minimizing pollutant reduction cost) while meeting the regional pollution control targets set by the central government, and a model that allocates the cooperation benefits (i.e., health improvement and cost reduction) among the participants according to their contributions using the Shapley value method. We applied CRM to the case of sulfur dioxide (SO 2 ) reduction in Yangtze River Delta region. Based on data from 2003 to 2013, and using mortality due to respiratory and cardiovascular diseases as the health endpoints, CRM saves 437 more lives than NCRM, amounting to 12.1% of the reduction under NCRM. CRM also reduced costs by US $65.8×10 6 compared with NCRM, which is 5.2% of the total cost of NCRM. Thus, CRM performs significantly better than NCRM. Each province obtains significant benefits from cooperation, which can motivate them to actively cooperate in the long term. A sensitivity analysis was performed to quantify the effects of parameter values on the cooperation benefits. Results shown that the CRM is not sensitive to the changes in each province's pollutant carrying capacity and the minimum pollutant removal capacity, but sensitive to the maximum pollutant reduction capacity. Moreover, higher cooperation benefits will be generated when a province's maximum pollutant reduction capacity increases. Copyright �

Cooperation, psychological game theory, and limitations of rationality in social interaction.

Science.gov (United States)

Colman, Andrew M

2003-04-01

Rational choice theory enjoys unprecedented popularity and influence in the behavioral and social sciences, but it generates intractable problems when applied to socially interactive decisions. In individual decisions, instrumental rationality is defined in terms of expected utility maximization. This becomes problematic in interactive decisions, when individuals have only partial control over the outcomes, because expected utility maximization is undefined in the absence of assumptions about how the other participants will behave. Game theory therefore incorporates not only rationality but also common knowledge assumptions, enabling players to anticipate their co-players' strategies. Under these assumptions, disparate anomalies emerge. Instrumental rationality, conventionally interpreted, fails to explain intuitively obvious features of human interaction, yields predictions starkly at variance with experimental findings, and breaks down completely in certain cases. In particular, focal point selection in pure coordination games is inexplicable, though it is easily achieved in practice; the intuitively compelling payoff-dominance principle lacks rational justification; rationality in social dilemmas is self-defeating; a key solution concept for cooperative coalition games is frequently inapplicable; and rational choice in certain sequential games generates contradictions. In experiments, human players behave more cooperatively and receive higher payoffs than strict rationality would permit. Orthodox conceptions of rationality are evidently internally deficient and inadequate for explaining human interaction. Psychological game theory, based on nonstandard assumptions, is required to solve these problems, and some suggestions along these lines have already been put forward.

BICM-based cooperative communication systems with relay selection: Constellation and multiplexer design

KAUST Repository

Malik, Muhammad Talha

2014-09-01

We propose a new bit-interleaved coded modulation (BICM)-based cooperative communication system where different BICM modules can be optimized jointly considering the average signal to noise ratios of the direct and the two-hop Rayleigh fading channels. As such, the full benefit of BICM can be exploited in the context of cooperative communication. Our design considers cooperative communication systems with so called max-min relay selection scheme that has no loss in performance in terms of diversity- multiplexing trade off in orthogonal cooperation. The presented numerical results for rate 1/2 convolutional code with 8-ary pulse amplitude modulation equivalently 64-ary quadrature amplitude modulation show that the proposed design can offer gains up to 1.4 dB over the traditional BICM design for a target bit error rate of 10-6. Moreover the results show that the amount of gain depends on the relays\\' positions and increases with the number of relays available for selection.

Effects of ethnicity on the relationship between vertical jump and maximal power on a cycle ergometer

Directory of Open Access Journals (Sweden)

Rouis Majdi

2016-06-01

Full Text Available The aim of this study was to verify the impact of ethnicity on the maximal power-vertical jump relationship. Thirty-one healthy males, sixteen Caucasian (age: 26.3 ± 3.5 years; body height: 179.1 ± 5.5 cm; body mass: 78.1 ± 9.8 kg and fifteen Afro-Caribbean (age: 24.4 ±2.6 years; body height: 178.9 ± 5.5 cm; body mass: 77.1 ± 10.3 kg completed three sessions during which vertical jump height and maximal power of lower limbs were measured. The results showed that the values of vertical jump height and maximal power were higher for Afro-Caribbean participants (62.92 ± 6.7 cm and 14.70 ± 1.75 W∙kg-1 than for Caucasian ones (52.92 ± 4.4 cm and 12.75 ± 1.36 W∙kg-1. Moreover, very high reliability indices were obtained on vertical jump (e.g. 0.95 < ICC < 0.98 and maximal power performance (e.g. 0.75 < ICC < 0.97. However, multiple linear regression analysis showed that, for a given value of maximal power, the Afro-Caribbean participants jumped 8 cm higher than the Caucasians. Together, these results confirmed that ethnicity impacted the maximal power-vertical jump relationship over three sessions. In the current context of cultural diversity, the use of vertical jump performance as a predictor of muscular power should be considered with caution when dealing with populations of different ethnic origins.

Thoughts on the International Cooperation and Exchanges of Chinese Research Universities

Science.gov (United States)

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…

Algebraic Number Precoded OFDM Transmission for Asynchronous Cooperative Multirelay Networks

Directory of Open Access Journals (Sweden)

Hua Jiang

2014-01-01

Full Text Available This paper proposes a space-time block coding (STBC transmission scheme for asynchronous cooperative systems. By combination of rotated complex constellations and Hadamard transform, these constructed codes are capable of achieving full cooperative diversity with the analysis of the pairwise error probability (PEP. Due to the asynchronous characteristic of cooperative systems, orthogonal frequency division multiplexing (OFDM technique with cyclic prefix (CP is adopted for combating timing delays from relay nodes. The total transmit power across the entire network is fixed and appropriate power allocation can be implemented to optimize the network performance. The relay nodes do not require decoding and demodulation operation, resulting in a low complexity. Besides, there is no delay for forwarding the OFDM symbols to the destination node. At the destination node the received signals have the corresponding STBC structure on each subcarrier. In order to reduce the decoding complexity, the sphere decoder is implemented for fast data decoding. Bit error rate (BER performance demonstrates the effectiveness of the proposed scheme.

On maximal massive 3D supergravity

OpenAIRE

Bergshoeff , Eric A; Hohm , Olaf; Rosseel , Jan; Townsend , Paul K

2010-01-01

ABSTRACT We construct, at the linearized level, the three-dimensional (3D) N = 4 supersymmetric " general massive supergravity " and the maximally supersymmetric N = 8 " new massive supergravity ". We also construct the maximally supersymmetric linearized N = 7 topologically massive supergravity, although we expect N = 6 to be maximal at the non-linear level. (Bergshoeff, Eric A) (Hohm, Olaf) (Rosseel, Jan) P.K.Townsend@da...

Turning Diversity into Competitive Advantage: A Case Study of Managing Diversity in the United States of America

Directory of Open Access Journals (Sweden)

Eddy M. Sutanto

2009-01-01

Full Text Available Esty, Griffin, and Hirsch (1995 state that today’s workforce is truly a mosaic of different races, ages, genders, ethnic groups, religions, and lifestyles. As a manager or a supervisor, it is your job to make sure that the desperate pieces of a mosaic fit together in a harmonious, coordinated way, maximally utilizing the talents and abilities of each employee. If skillfully managed, this diversity can bring a competitive advantage to an organization. If not, however, the bottom line can be negatively affected, and the work environment can become unwelcoming. Dealing with a diverse work group is new terrain for most managers and supervisors. The United States rose to the top using a-one-size-fits-all approach to managing employees. This work in past because, historically, most of the work force was white, and male. This has all changed. The following parts will clearly provide a description about diversity, changes in the United States work force, challenges and opportunities of the changes for organizations, and how managers and supervisors as front liners deal with diversity and to turn diversity into a competitive advantage.

Ethnic Forces in Collective Action: Diversity, Dominance, and Irrigation in Tamil Nadu

Directory of Open Access Journals (Sweden)

Timothy M. Waring

2011-12-01

Full Text Available Mounting evidence suggests that ethnic interactions damage cooperation in the provision of public goods, yet very few studies of collective action in common pool resource management have found strong evidence for the effects of ethnic diversity. Research on both public goods and common pool resource management that does find negative ethnic effects on cooperation tend to ignore the importance of interethnic relationships, particularly ethnic inequality, stratification, or dominance. This study presents data from agricultural villages in Tamil Nadu's Palani Hills to test the importance of a range of ethnic effects using caste interactions in a traditional irrigation system. I provide corroborating evidence of a negative cooperative effect of ethnic diversity, but also demonstrate that factors of ethnic dominance such as hierarchical stratification and demographic dominance strongly determine outcomes in collective irrigation management. I argue that the most important measure of equity, irrigation access, is socially, technologically, and institutionally embedded, and demonstrate that the distribution of irrigation channels is explained by measures of inequality, such as wealth inequality, Dalit status, and demographic dominance.

Inclusive fitness maximization: An axiomatic approach.

Science.gov (United States)

Okasha, Samir; Weymark, John A; Bossert, Walter

2014-06-07

Kin selection theorists argue that evolution in social contexts will lead organisms to behave as if maximizing their inclusive, as opposed to personal, fitness. The inclusive fitness concept allows biologists to treat organisms as akin to rational agents seeking to maximize a utility function. Here we develop this idea and place it on a firm footing by employing a standard decision-theoretic methodology. We show how the principle of inclusive fitness maximization and a related principle of quasi-inclusive fitness maximization can be derived from axioms on an individual׳s 'as if preferences' (binary choices) for the case in which phenotypic effects are additive. Our results help integrate evolutionary theory and rational choice theory, help draw out the behavioural implications of inclusive fitness maximization, and point to a possible way in which evolution could lead organisms to implement it. Copyright © 2014 Elsevier Ltd. All rights reserved.

Functional & phylogenetic diversity of copepod communities

Science.gov (United States)

Benedetti, F.; Ayata, S. D.; Blanco-Bercial, L.; Cornils, A.; Guilhaumon, F.

2016-02-01

The diversity of natural communities is classically estimated through species identification (taxonomic diversity) but can also be estimated from the ecological functions performed by the species (functional diversity), or from the phylogenetic relationships among them (phylogenetic diversity). Estimating functional diversity requires the definition of specific functional traits, i.e., phenotypic characteristics that impact fitness and are relevant to ecosystem functioning. Estimating phylogenetic diversity requires the description of phylogenetic relationships, for instance by using molecular tools. In the present study, we focused on the functional and phylogenetic diversity of copepod surface communities in the Mediterranean Sea. First, we implemented a specific trait database for the most commonly-sampled and abundant copepod species of the Mediterranean Sea. Our database includes 191 species, described by seven traits encompassing diverse ecological functions: minimal and maximal body length, trophic group, feeding type, spawning strategy, diel vertical migration and vertical habitat. Clustering analysis in the functional trait space revealed that Mediterranean copepods can be gathered into groups that have different ecological roles. Second, we reconstructed a phylogenetic tree using the available sequences of 18S rRNA. Our tree included 154 of the analyzed Mediterranean copepod species. We used these two datasets to describe the functional and phylogenetic diversity of copepod surface communities in the Mediterranean Sea. The replacement component (turn-over) and the species richness difference component (nestedness) of the beta diversity indices were identified. Finally, by comparing various and complementary aspects of plankton diversity (taxonomic, functional, and phylogenetic diversity) we were able to gain a better understanding of the relationships among the zooplankton community, biodiversity, ecosystem function, and environmental forcing.

Book Review: Diversity in European Marketing

OpenAIRE

Hana Machková

2012-01-01

The case book “Diversity in European Marketing” is the result of the scientific cooperation of the CEMS Marketing Faculty Group. Prestigious Central European Universities - Corvinius University of Budapest and University of Economic, Prague - are members of CEMS - the Global Alliance in Management Education of 26 leading business schools and 70 multinational companies. Four authors from these two Universities share in this book their experience of Central European Marketing specifics.

International cooperation

International Nuclear Information System (INIS)

2008-01-01

In this chapter international cooperation of the Division for Radiation Safety, NPP Decommissioning and Radwaste Management of the VUJE, a. s. is presented. Very important is cooperation with the International Atomic Energy Agency. This cooperation has various forms - national and regional projects of technical cooperation, coordinated research activities, participation of our experts in preparation of the IAEA documentation etc.

How diverse are diversity assessment methods? A comparative analysis and benchmarking of molecular descriptor space.

Science.gov (United States)

Koutsoukas, Alexios; Paricharak, Shardul; Galloway, Warren R J D; Spring, David R; Ijzerman, Adriaan P; Glen, Robert C; Marcus, David; Bender, Andreas

2014-01-27

Chemical diversity is a widely applied approach to select structurally diverse subsets of molecules, often with the objective of maximizing the number of hits in biological screening. While many methods exist in the area, few systematic comparisons using current descriptors in particular with the objective of assessing diversity in bioactivity space have been published, and this shortage is what the current study is aiming to address. In this work, 13 widely used molecular descriptors were compared, including fingerprint-based descriptors (ECFP4, FCFP4, MACCS keys), pharmacophore-based descriptors (TAT, TAD, TGT, TGD, GpiDAPH3), shape-based descriptors (rapid overlay of chemical structures (ROCS) and principal moments of inertia (PMI)), a connectivity-matrix-based descriptor (BCUT), physicochemical-property-based descriptors (prop2D), and a more recently introduced molecular descriptor type (namely, "Bayes Affinity Fingerprints"). We assessed both the similar behavior of the descriptors in assessing the diversity of chemical libraries, and their ability to select compounds from libraries that are diverse in bioactivity space, which is a property of much practical relevance in screening library design. This is particularly evident, given that many future targets to be screened are not known in advance, but that the library should still maximize the likelihood of containing bioactive matter also for future screening campaigns. Overall, our results showed that descriptors based on atom topology (i.e., fingerprint-based descriptors and pharmacophore-based descriptors) correlate well in rank-ordering compounds, both within and between descriptor types. On the other hand, shape-based descriptors such as ROCS and PMI showed weak correlation with the other descriptors utilized in this study, demonstrating significantly different behavior. We then applied eight of the molecular descriptors compared in this study to sample a diverse subset of sample compounds (4%) from an

Developments in cooperative learning: review of research

Directory of Open Access Journals (Sweden)

Robyn M. Gillies

2014-10-01

Full Text Available Cooperative learning, where students work in small groups to accomplish shared goals, is widely recognized as a teaching strategy that promotes learning and socialization among students from kindergarten through college and across different subject domains. It has been used successfully to promote reading and writing achievements, understanding and conceptual development in science classes, problem-solving in mathematics, and higher-order thinking and learning to name just a few. It has been shown to enhance students' willingness to work cooperatively and productively with others with diverse learning and adjustment needs and to enhance intergroup relations with those from culturally and ethnically different backgrounds. It has also been used as a teaching strategy to assist students to manage conflict and to help students identified as bullies learn appropriate interpersonal skills. In fact, it has been argued that cooperative learning experiences are crucial to preventing and alleviating many of the social problems related to children, adolescents, and young adults. There is no doubt that the benefits attributed to cooperative learning are widespread and numerous and it is the apparent success of this approach to learning that has led to it being acclaimed as one of the greatest educational innovations of recent times. The purpose of this paper is not only to review developments in research on cooperative learning but also to examine the factors that mediate and moderate its success. In particular, the review focuses on the types of student and teacher interactions generated and the key role talk plays in developing student thinking and learning, albeit through the expression of contrasting opinions or constructed shared meaning. The intention is to provide additional insights on how teachers can effectively utilize this pedagogical approach to teaching and learning in their classrooms.

Asia-Europe cooperation on energy security an overview of options and challenges

Energy Technology Data Exchange (ETDEWEB)

Nicolas, F.; Godement, F.; Yakushiji, T

2005-07-01

Asian and European economies are major players on the international energy markets. Because of broad similarities in the energy situation in both regions, and also because of some existing major differences, there is definitely scope for joint discussions and cooperation on energy issues between the countries of the two regions, despite possible competing interests. This document aims at examining the conditions for this possible cooperation, as well as the major incentives and obstacles. After a brief reminder on the notion of energy security, a first section provides a synthesis of the energy situation and outlook in the two regions. The next section focuses more specifically on energy security issues and policies, emphasizing the diversity of strategies followed in the two regions. The last section concludes by sketching possible avenues for cooperation on energy issues between countries of the two regions.

Asia-Europe cooperation on energy security an overview of options and challenges

International Nuclear Information System (INIS)

Nicolas, F.; Godement, F.; Yakushiji, T.

2005-01-01

Asian and European economies are major players on the international energy markets. Because of broad similarities in the energy situation in both regions, and also because of some existing major differences, there is definitely scope for joint discussions and cooperation on energy issues between the countries of the two regions, despite possible competing interests. This document aims at examining the conditions for this possible cooperation, as well as the major incentives and obstacles. After a brief reminder on the notion of energy security, a first section provides a synthesis of the energy situation and outlook in the two regions. The next section focuses more specifically on energy security issues and policies, emphasizing the diversity of strategies followed in the two regions. The last section concludes by sketching possible avenues for cooperation on energy issues between countries of the two regions

Maximal Entanglement in High Energy Physics

Directory of Open Access Journals (Sweden)

Alba Cervera-Lierta, José I. Latorre, Juan Rojo, Luca Rottoli

2017-11-01

Full Text Available We analyze how maximal entanglement is generated at the fundamental level in QED by studying correlations between helicity states in tree-level scattering processes at high energy. We demonstrate that two mechanisms for the generation of maximal entanglement are at work: i $s$-channel processes where the virtual photon carries equal overlaps of the helicities of the final state particles, and ii the indistinguishable superposition between $t$- and $u$-channels. We then study whether requiring maximal entanglement constrains the coupling structure of QED and the weak interactions. In the case of photon-electron interactions unconstrained by gauge symmetry, we show how this requirement allows reproducing QED. For $Z$-mediated weak scattering, the maximal entanglement principle leads to non-trivial predictions for the value of the weak mixing angle $\\theta_W$. Our results are a first step towards understanding the connections between maximal entanglement and the fundamental symmetries of high-energy physics.

Supporting Diverse Young Adolescents: Cooperative Grouping in Inclusive Middle-Level Settings

Science.gov (United States)

Miller, Nicole C.; McKissick, Bethany R.; Ivy, Jessica T.; Moser, Kelly

2017-01-01

The middle level classroom presents unique challenges to educators who strive to provide opportunities that acknowledge learner diversity in terms of social, cognitive, physical, and emotional development. This is confounded even further within inclusive middle-school classrooms where the responsibility to differentiate instruction is even more…

Maximal Inequalities for Dependent Random Variables

DEFF Research Database (Denmark)

Hoffmann-Jorgensen, Jorgen

2016-01-01

Maximal inequalities play a crucial role in many probabilistic limit theorem; for instance, the law of large numbers, the law of the iterated logarithm, the martingale limit theorem and the central limit theorem. Let X-1, X-2,... be random variables with partial sums S-k = X-1 + ... + X-k. Then a......Maximal inequalities play a crucial role in many probabilistic limit theorem; for instance, the law of large numbers, the law of the iterated logarithm, the martingale limit theorem and the central limit theorem. Let X-1, X-2,... be random variables with partial sums S-k = X-1 + ... + X......-k. Then a maximal inequality gives conditions ensuring that the maximal partial sum M-n = max(1) (...

An ethical justification of profit maximization

DEFF Research Database (Denmark)

Koch, Carsten Allan

2010-01-01

In much of the literature on business ethics and corporate social responsibility, it is more or less taken for granted that attempts to maximize profits are inherently unethical. The purpose of this paper is to investigate whether an ethical argument can be given in support of profit maximizing...... behaviour. It is argued that some form of consequential ethics must be applied, and that both profit seeking and profit maximization can be defended from a rule-consequential point of view. It is noted, however, that the result does not apply unconditionally, but requires that certain form of profit (and...... utility) maximizing actions are ruled out, e.g., by behavioural norms or formal institutions....

Reallocation of water in the state of New Mexico based on cooperative game theory

Science.gov (United States)

Rouhi Rad, M.

2011-12-01

Water allocation models often aim to maximize net benefits in the river basin based on the water rights, thus there is no motivation to use water efficiently by the users with lower marginal value for water. Water markets not only could help increase the net benefits over the basin but also will encourage the stakeholders to save the water and use it in transfer markets and increase their income. This issue can be viewed as a game in which stakeholders can play non-cooperatively and try to increase their own benefits using the amount of water assigned to them or they could cooperate and make coalitions in order to increase the total benefits in the coalition and the whole basin. The aim of this study is to reallocate the water based on cooperation among different stakeholders, namely agricultural, municipal and industrial and environmental, in the Upper Rio Grande river basin in the state of New Mexico in order to increase efficiency, sustainability and equity of water distribution in the basin using different game theory schemes such as Nucleolus and the Shapley Value.

A Novel Optimal Joint Resource Allocation Method in Cooperative Multicarrier Networks: Theory and Practice

Directory of Open Access Journals (Sweden)

Yuan Gao

2016-04-01

Full Text Available With the increasing demands for better transmission speed and robust quality of service (QoS, the capacity constrained backhaul gradually becomes a bottleneck in cooperative wireless networks, e.g., in the Internet of Things (IoT scenario in joint processing mode of LTE-Advanced Pro. This paper focuses on resource allocation within capacity constrained backhaul in uplink cooperative wireless networks, where two base stations (BSs equipped with single antennae serve multiple single-antennae users via multi-carrier transmission mode. In this work, we propose a novel cooperative transmission scheme based on compress-and-forward with user pairing to solve the joint mixed integer programming problem. To maximize the system capacity under the limited backhaul, we formulate the joint optimization problem of user sorting, subcarrier mapping and backhaul resource sharing among different pairs (subcarriers for users. A novel robust and efficient centralized algorithm based on alternating optimization strategy and perfect mapping is proposed. Simulations show that our novel method can improve the system capacity significantly under the constraint of the backhaul resource compared with the blind alternatives.

Optimal distribution of incentives for public cooperation in heterogeneous interaction environments

Directory of Open Access Journals (Sweden)

Xiaojie eChen

2014-07-01

Full Text Available In the framework of evolutionary games with institutional reciprocity, limited incentives are at disposal for rewarding cooperators and punishing defectors. In the simplest case, it can be assumed that, depending on their strategies, all players receive equal incentives from the common pool. The question arises, however, what is the optimal distribution of institutional incentives? How should we best reward and punish individuals for cooperation to thrive? We study this problem for the public goods game on a scale-free network. We show that if the synergetic effects of group interactions are weak, the level of cooperation in the population can be maximized simply by adopting the simplest ''equal distribution'' scheme. If synergetic effects are strong, however, it is best to reward high-degree nodes more than low-degree nodes. These distribution schemes for institutional rewards are independent of payoff normalization. For institutional punishment, however, the same optimization problem is more complex, and its solution depends on whether absolute or degree-normalized payoffs are used. We find that degree-normalized payoffs require high-degree nodes be punished more lenient than low-degree nodes. Conversely, if absolute payoffs count, then high-degree nodes should be punished stronger than low-degree nodes.

Complementary Variety: When Can Cooperation in Uncertain Environments Outperform Competitive Selection?

Directory of Open Access Journals (Sweden)

Martin Hilbert

2017-01-01

Full Text Available Evolving biological and socioeconomic populations can sometimes increase their growth rate by cooperatively redistributing resources among their members. In unchanging environments, this simply comes down to reallocating resources to fitter types. In uncertain and fluctuating environments, cooperation cannot always outperform blind competitive selection. When can it? The conditions depend on the particular shape of the fitness landscape. The article derives a single measure that quantifies by how much an intervention in stochastic environments can possibly outperform the blind forces of natural selection. It is a multivariate and multilevel measure that essentially quantifies the amount of complementary variety between different population types and environmental states. The more complementary the fitness of types in different environmental states, the proportionally larger the potential benefit of strategic cooperation over competitive selection. With complementary variety, holding population shares constant will always outperform natural and market selection (including bet-hedging, portfolio management, and stochastic switching. The result can be used both to determine the acceptable cost of learning the details of a fitness landscape and to design multilevel classification systems of population types and environmental states that maximize population growth. Two empirical cases are explored, one from the evolving economy and the other one from migrating birds.

Reducing Ambulance Diversion at Hospital and Regional Levels: Systemic Review of Insights from Simulation Models

Directory of Open Access Journals (Sweden)

M Kit Delgado

2013-09-01

Full Text Available Introduction: Optimal solutions for reducing diversion without worsening emergency department (ED crowding are unclear. We performed a systematic review of published simulation studies to identify: 1 the tradeoff between ambulance diversion and ED wait times; 2 the predicted impact of patient flow interventions on reducing diversion; and 3 the optimal regional strategy for reducing diversion.Methods: Data Sources: Systematic review of articles using MEDLINE, Inspec, Scopus. Additional studies identified through bibliography review, Google Scholar, and scientific conference proceedings. Study Selection: Only simulations modeling ambulance diversion as a result of ED crowding or inpatient capacity problems were included. Data extraction: Independent extraction by two authors using predefined data fields.Results: We identified 5,116 potentially relevant records; 10 studies met inclusion criteria. In models that quantified the relationship between ED throughput times and diversion, diversion was found to only minimally improve ED waiting room times. Adding holding units for inpatient boarders and ED-based fast tracks, improving lab turnaround times, and smoothing elective surgery caseloads were found to reduce diversion considerably. While two models found a cooperative agreement between hospitals is necessary to prevent defensive diversion behavior by a hospital when a nearby hospital goes on diversion, one model found there may be more optimal solutions for reducing region wide wait times than a regional ban on diversion.Conclusion: Smoothing elective surgery caseloads, adding ED fast tracks as well as holding units for inpatient boarders, improving ED lab turnaround times, and implementing regional cooperative agreements among hospitals. [West J Emerg Med. 2013;14(5:489-498.

Evolution of cooperation: combining kin selection and reciprocal altruism into matrix games with social dilemmas.

Directory of Open Access Journals (Sweden)

Som B Ale

Full Text Available Darwinian selection should preclude cooperation from evolving; yet cooperation is widespread among organisms. We show how kin selection and reciprocal altruism can promote cooperation in diverse 2×2 matrix games (prisoner's dilemma, snowdrift, and hawk-dove. We visualize kin selection as non-random interactions with like-strategies interacting more than by chance. Reciprocal altruism emerges from iterated games where players have some likelihood of knowing the identity of other players. This perspective allows us to combine kin selection and reciprocal altruism into a general matrix game model. Both mechanisms operating together should influence the evolution of cooperation. In the absence of kin selection, reciprocal altruism may be an evolutionarily stable strategy but is unable to invade a population of non-co-operators. Similarly, it may take a high degree of relatedness to permit cooperation to supplant non-cooperation. Together, a little bit of reciprocal altruism can, however, greatly reduce the threshold at which kin selection promotes cooperation, and vice-versa. To properly frame applications and tests of cooperation, empiricists should consider kin selection and reciprocal altruism together rather than as alternatives, and they should be applied to a broader class of social dilemmas than just the prisoner's dilemma.

Non-cooperative game theory in biology and cooperative reasoning in humans.

Science.gov (United States)

Kabalak, Alihan; Smirnova, Elena; Jost, Jürgen

2015-06-01

The readiness for spontaneous cooperation together with the assumptions that others share this cooperativity has been identified as a fundamental feature that distinguishes humans from other animals, including the great apes. At the same time, cooperativity presents an evolutionary puzzle because non-cooperators do better in a group of cooperators. We develop here an analysis of the process leading to cooperation in terms of rationality concepts, game theory and epistemic logic. We are, however, not attempting to reconstruct the actual evolutionary process. We rather want to provide the logical structure underlying cooperation in order to understand why cooperation is possible and what kind of reasoning and beliefs would lead to cooperative decision-making. Game theory depends on an underlying common belief in non-cooperative rationality of the players, and cooperativity similarly can utilize a common belief in cooperative rationality as its basis. We suggest a weaker concept of rational decision-making in games that encompasses both types of decision-making. We build this up in stages, starting from simple optimization, then using anticipation of the reaction of others, to finally arrive at reflexive and cooperative reasoning. While each stage is more difficult than the preceding, importantly, we also identify a reduction of complexity achieved by the consistent application of higher stage reasoning.

Designing for cooperation - cooperating in design

DEFF Research Database (Denmark)

Kyng, Morten

1991-01-01

This article will discuss how to design computer applications that enhance the quality of work and products, and will relate the discussion to current themes in the field of Computer-Supported Cooperative Work (CSCW). Cooperation is a key element of computer use and work practice, yet here...... a specific "CSCW approach is not taken." Instead the focus is cooperation as an important aspect of work that should be integrated into most computer support efforts in order to develop successful computer support, however, other aspects such as power, conflict and control must also be considered....

Cooperative Antibiotic Resistance in a Multi-Drug Environment

Science.gov (United States)

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.

Capital Accumulation in a Region. Cooperatives Versus Foreign Direct Investments

Directory of Open Access Journals (Sweden)

Zimnoch Krystyna

2016-09-01

Full Text Available The main aim of this article is to demonstrate the ability of cooperatives to create internal resources of a region through foreign direct investments and the creation of financial, physical, human, and social capital. It concerns the comparing and emphasizing of the stability of resources created in a region by these forms of action. In order to demonstrate the stability of internal resources of a region, generated through foreign direct investment, a research was conducted involving the analysis of the rankings of the largest foreign investors in Poland, statistical data from the Central Statistical Office and the NBP, showing the inflow and outflow of FDIs, the number of companies with foreign capital participation, and the number of people working in them. In addition, a case study was used for the regions where the investments have been withdrawn, showing the importance of cooperatives for the stabilization of the potential of the regions. The study shows that the transfer of FDIs is always guided by the maximization of profit, tax optimization of a location, and the native currency exchange rate fluctuations. The following consequences of withdrawal have no significance to foreign investors but affect the regions: the increase in the unemployment rate, the reduction in the income of local residents, the increase in debt, the acquisition of real estate purchased on credit. The case study shows that cooperative enterprises can replace foreign capital in the region, ensuring the stability and durability of its internal resources. The concepts and strategies for regional development should focus on cooperatives as a way to create the internal resources of a region, which are seen as the current development source. Co-operatives can prevent the leaching of resources and backwash effects. The economic policy must ensure the equal treatment of all of the entities investing in the region. Currently, Poland gives the priority to foreign investors

Volunteering as Red Queen Mechanism for Cooperation in Public Goods Games

Science.gov (United States)

Hauert, Christoph; De Monte, Silvia; Hofbauer, Josef; Sigmund, Karl

2002-05-01

The evolution of cooperation among nonrelated individuals is one of the fundamental problems in biology and social sciences. Reciprocal altruism fails to provide a solution if interactions are not repeated often enough or groups are too large. Punishment and reward can be very effective but require that defectors can be traced and identified. Here we present a simple but effective mechanism operating under full anonymity. Optional participation can foil exploiters and overcome the social dilemma. In voluntary public goods interactions, cooperators and defectors will coexist. We show that this result holds under very diverse assumptions on population structure and adaptation mechanisms, leading usually not to an equilibrium but to an unending cycle of adjustments (a Red Queen type of evolution). Thus, voluntary participation offers an escape hatch out of some social traps. Cooperation can subsist in sizable groups even if interactions are not repeated, defectors remain anonymous, players have no memory, and assortment is purely random.

A new approach towards the enhancement of northeast Asian economic cooperation

Directory of Open Access Journals (Sweden)

Chang-Jae Lee

1999-09-01

Full Text Available This study proposes the formation of the Northeast Asian Economic Cooperation Council (NAECC to discuss comprehensive economic cooperation and major economic issues between Korea, Japan and China. In order to meet the challenge of risign regionalism and to prevent another Asian economic crisis, it is imperative for the central governments of the region to involve themselves more actively in Northeast Asian Economic Cooperation. Given the diversity of Northeast Asian countries, it seems to be more realistic to vegin with the central governments of the three major countries in terms of economic size. However, even amongst these three countries, the prospects for reaching a regional trade agreement such as the North American Free Trade Agreement (NAFTA, let alone a more advanced economic integration type like the EU, are quite dim in the foreseeable future. Thus, Korea, Japan and China must try to get as many benefits of economic integration as possible through a non-traditional approach.

Inclusive Fitness Maximization:An Axiomatic Approach

OpenAIRE

Okasha, Samir; Weymark, John; Bossert, Walter

2014-01-01

Kin selection theorists argue that evolution in social contexts will lead organisms to behave as if maximizing their inclusive, as opposed to personal, fitness. The inclusive fitness concept allows biologists to treat organisms as akin to rational agents seeking to maximize a utility function. Here we develop this idea and place it on a firm footing by employing a standard decision-theoretic methodology. We show how the principle of inclusive fitness maximization and a related principle of qu...

Coalition Formation and Spectrum Sharing of Cooperative Spectrum Sensing Participants.

Science.gov (United States)

Zhensheng Jiang; Wei Yuan; Leung, Henry; Xinge You; Qi Zheng

2017-05-01

In cognitive radio networks, self-interested secondary users (SUs) desire to maximize their own throughput. They compete with each other for transmit time once the absence of primary users (PUs) is detected. To satisfy the requirement of PU protection, on the other hand, they have to form some coalitions and cooperate to conduct spectrum sensing. Such dilemma of SUs between competition and cooperation motivates us to study two interesting issues: 1) how to appropriately form some coalitions for cooperative spectrum sensing (CSS) and 2) how to share transmit time among SUs. We jointly consider these two issues, and propose a noncooperative game model with 2-D strategies. The first dimension determines coalition formation, and the second indicates transmit time allocation. Considering the complexity of solving this game, we decompose the game into two more tractable ones: one deals with the formation of CSS coalitions, and the other focuses on the allocation of transmit time. We characterize the Nash equilibria (NEs) of both games, and show that the combination of these two NEs corresponds to the NE of the original game. We also develop a distributed algorithm to achieve a desirable NE of the original game. When this NE is achieved, the SUs obtain a Dhp-stable coalition structure and a fair transmit time allocation. Numerical results verify our analyses, and demonstrate the effectiveness of our algorithm.

Does mental exertion alter maximal muscle activation?

Directory of Open Access Journals (Sweden)

Vianney eRozand

2014-09-01

Full Text Available Mental exertion is known to impair endurance performance, but its effects on neuromuscular function remain unclear. The purpose of this study was to test the hypothesis that mental exertion reduces torque and muscle activation during intermittent maximal voluntary contractions of the knee extensors. Ten subjects performed in a randomized order three separate mental exertion conditions lasting 27 minutes each: i high mental exertion (incongruent Stroop task, ii moderate mental exertion (congruent Stroop task, iii low mental exertion (watching a movie. In each condition, mental exertion was combined with ten intermittent maximal voluntary contractions of the knee extensor muscles (one maximal voluntary contraction every 3 minutes. Neuromuscular function was assessed using electrical nerve stimulation. Maximal voluntary torque, maximal muscle activation and other neuromuscular parameters were similar across mental exertion conditions and did not change over time. These findings suggest that mental exertion does not affect neuromuscular function during intermittent maximal voluntary contractions of the knee extensors.

Annotated Bibliography of Diversity Research Issues in the Navy and U. S. Military

National Research Council Canada - National Science Library

Burress, Landrus; Uriell, Zannette A; Kee, Amanda R; Rosenfeld, Paul; Alderton, David L

2008-01-01

... and parenthood in the Navy. Recently, top Navy leadership has expressed support for an encompassing diversity framework to guide Navy policy in these areas with the goals being to maximize teamwork and productivity so as to...

Enhancing social skills through cooperative learning

Directory of Open Access Journals (Sweden)

M J Booysen

2008-04-01

Full Text Available The National Curriculum Statement of South Africa envisages qualified and competent teachers to deal with the diversity of learners and their needs in the classroom. One of the needs refers to all learners (Gr R-12 who need to acquire the necessary social skills to enable them to work effectively with others as members of a team, group, organization and community. These skills refer inter alia to: learning to work with others, listening to others, giving attention, asking clarifying questions, learning how to evaluate, and to praise others, handling conflict, reflecting on group work and allowing all group members to participate. The most obvious place to deal purposefully with the development of social skills is the classroom. This implies that alternative ways and methods of teaching must be introduced to develop the necessary social skills. This article reports on the findings obtained from a combined quantitative and qualitative study that set out to determine the levels of social competence achieved by a group of Grade 2 learners, and the possible association of a cooperative teaching and learning intervention programme for enhancing the social skills of these learners. The results revealed the latent potential of cooperative learning to enhance the social skills of Grade 2 learners. The significance of this research lies in the contribution it makes to establish the social competence of a group of Grade 2 learners and to determine the possibilities for enhancing their social skills through cooperative learning.

DEADS: Depth and Energy Aware Dominating Set Based Algorithm for Cooperative Routing along with Sink Mobility in Underwater WSNs

Directory of Open Access Journals (Sweden)

Amara Umar

2015-06-01

Full Text Available Performance enhancement of Underwater Wireless Sensor Networks (UWSNs in terms of throughput maximization, energy conservation and Bit Error Rate (BER minimization is a potential research area. However, limited available bandwidth, high propagation delay, highly dynamic network topology, and high error probability leads to performance degradation in these networks. In this regard, many cooperative communication protocols have been developed that either investigate the physical layer or the Medium Access Control (MAC layer, however, the network layer is still unexplored. More specifically, cooperative routing has not yet been jointly considered with sink mobility. Therefore, this paper aims to enhance the network reliability and efficiency via dominating set based cooperative routing and sink mobility. The proposed work is validated via simulations which show relatively improved performance of our proposed work in terms the selected performance metrics.

On maximal surfaces in asymptotically flat space-times

International Nuclear Information System (INIS)

Bartnik, R.; Chrusciel, P.T.; O Murchadha, N.

1990-01-01

Existence of maximal and 'almost maximal' hypersurfaces in asymptotically flat space-times is established under boundary conditions weaker than those considered previously. We show in particular that every vacuum evolution of asymptotically flat data for Einstein equations can be foliated by slices maximal outside a spatially compact set and that every (strictly) stationary asymptotically flat space-time can be foliated by maximal hypersurfaces. Amongst other uniqueness results, we show that maximal hypersurface can be used to 'partially fix' an asymptotic Poincare group. (orig.)

Insulin resistance and maximal oxygen uptake

DEFF Research Database (Denmark)

Seibaek, Marie; Vestergaard, Henrik; Burchardt, Hans

2003-01-01

BACKGROUND: Type 2 diabetes, coronary atherosclerosis, and physical fitness all correlate with insulin resistance, but the relative importance of each component is unknown. HYPOTHESIS: This study was undertaken to determine the relationship between insulin resistance, maximal oxygen uptake......, and the presence of either diabetes or ischemic heart disease. METHODS: The study population comprised 33 patients with and without diabetes and ischemic heart disease. Insulin resistance was measured by a hyperinsulinemic euglycemic clamp; maximal oxygen uptake was measured during a bicycle exercise test. RESULTS......: There was a strong correlation between maximal oxygen uptake and insulin-stimulated glucose uptake (r = 0.7, p = 0.001), and maximal oxygen uptake was the only factor of importance for determining insulin sensitivity in a model, which also included the presence of diabetes and ischemic heart disease. CONCLUSION...

POLITENESS MAXIM OF MAIN CHARACTER IN SECRET FORGIVEN

Directory of Open Access Journals (Sweden)

Sang Ayu Isnu Maharani

2017-06-01

Full Text Available Maxim of Politeness is an interesting subject to be discussed, since politeness has been criticized from our childhood. We are obliques to be polite to anyone either in speaking or in acting. Somehow we are manage to show politeness in our spoken expression though our intention might be not so polite. For example we must appriciate others opinion although we feel objection toward the opinion. In this article the analysis of politeness is based on maxim proposes by Leech. He proposed six types of politeness maxim. The discussion shows that the main character (Kristen and Kami use all types of maxim in their conversation. The most commonly used are approbation maxim and agreement maxim

Performance analysis of selective cooperation in underlay cognitive networks over Rayleigh channels

KAUST Repository

Hussain, Syed Imtiaz

2011-06-01

Underlay cognitive networks should follow strict interference thresholds to operate in parallel with primary networks. This constraint limits their transmission power and eventually the area of coverage. Therefore, it is very likely that the underlay networks will make use of relays to transmit signals to the distant secondary users. In this paper, we propose a secondary relay selection scheme which maximizes the end-to-end signal to noise ratio (SNR) for the secondary link while keeping the interference levels to the primary network below a certain threshold. We derive closed form expressions for the probability density function (PDF) of the SNR at the secondary destination, average bit error probability and outage probability. Analytical results are verified through simulations which also give insight about the benefits and tradeoffs of the selective cooperation in underlay cognitive networks. It is shown that, in contrast to non-cognitive selective cooperation, this scheme performs better in low SNR region for cognitive networks. © 2011 IEEE.

Learning to Cooperate: The Evolution of Social Rewards in Repeated Interactions.

Science.gov (United States)

Dridi, Slimane; Akçay, Erol

2018-01-01

Understanding the behavioral and psychological mechanisms underlying social behaviors is one of the major goals of social evolutionary theory. In particular, a persistent question about animal cooperation is to what extent it is supported by other-regarding preferences-the motivation to increase the welfare of others. In many situations, animals adjust their behaviors through learning by responding to the rewards they experience as a consequence of their actions. Therefore, we may ask whether learning in social situations can be driven by evolved other-regarding rewards. Here we develop a mathematical model in order to ask whether the mere act of cooperating with a social partner will evolve to be inherently rewarding. Individuals interact repeatedly in pairs and adjust their behaviors through reinforcement learning. We assume that individuals associate with each game outcome an internal reward value. These perceived rewards are genetically evolving traits. We find that conditionally cooperative rewards that value mutual cooperation positively but the sucker's outcome negatively tend to be evolutionarily stable. Purely other-regarding rewards can evolve only under special parameter combinations. On the other hand, selfish rewards that always lead to pure defection are also evolutionarily successful. These findings are consistent with empirical observations showing that humans tend to display conditionally cooperative behavior and also exhibit a diversity of preferences. Our model also demonstrates the need to further integrate multiple levels of biological causation of behavior.

A unified MGF-based capacity analysis of diversity combiners over generalized fading channels

KAUST Repository

Yilmaz, Ferkan; Alouini, Mohamed-Slim

2012-01-01

Unified exact ergodic capacity results for L-branch coherent diversity combiners including equal-gain combining (EGC) and maximal-ratio combining (MRC) are not known. This paper develops a novel generic framework for the capacity analysis of L-branch

Performance Analysis of Reuse Distance in Cooperative Broadcasting

Directory of Open Access Journals (Sweden)

Jimmi Grönkvist

2016-01-01

Full Text Available Cooperative broadcasting is a promising technique for robust broadcast with low overhead and delay in mobile ad hoc networks. The technique is attractive for mission-oriented mobile communication, where a majority of the traffic is of broadcast nature. In cooperative broadcasting, all nodes simultaneously retransmit packets. The receiver utilizes cooperative diversity in the simultaneously received signals. The retransmissions continue until all nodes are reached. After the packet has traveled a specific number of hops out from the source, denoted as reuse distance, the source node transmits a new broadcast packet in the time slot used for the previous broadcast packet. If the reuse distance is too small, interference causes packet loss in intermediate nodes. In the literature, a reuse distance of three is common. With an analysis based on a realistic interference model and real terrain data, we show that a reuse distance of at least four is necessary to avoid packet loss in sparsely connected networks, especially for high spectral efficiencies. For frequency hopping, widely used in military systems, we propose a novel method. This method almost eliminates interference for a reuse distance of three, increasing the throughput by 33% compared to systems with a reuse distance of four.

Cross-border Co-operation and Policy Networks in West Africa

DEFF Research Database (Denmark)

Trémolières, Marie; Walther, Olivier

This publication examines how policy actors involved in cross-border co-operation contribute to the regional integration process in West Africa. It uses a pioneering methodology, known as social network analysis, to visualise the formal and informal relationships between actors involved in cross...... West Africa to develop cross-border initiatives in a number of ways. Combining these two analyses with the perceptions of regional policy makers as to which border areas they consider as priorities for regional integration, the publication concludes with the analytical foundations for more effective......-border policy networks, showing that borders have notable and diverse impacts on exchanges of information and the relative power of networks. The report then analyses a range of regional indicators of co-operation potential, visually demonstrating that borders can also affect the ability of sub-regions within...

Physical Layer Security for Cooperative Relaying Over Generalized-K Fading Channels

KAUST Repository

Wu, Ling; Yang, Liang; Chen, Jianchao; Alouini, Mohamed-Slim

2018-01-01

In this letter, we analyze the secrecy performance for a cooperative diversity system with amplify-and-forward (AF) over generalized-K fading channels. More specifically, some lower bounds on the secrecy performance, such as secure outage probability (SOP), average secrecy capacity (ASC), and strictly positive secrecy capacity (SPSC), are derived in closed-form. Finally, we provide simulation results to verify the accuracy of our analytical results.

Physical Layer Security for Cooperative Relaying Over Generalized-K Fading Channels

KAUST Repository

Wu, Ling

2018-02-02

In this letter, we analyze the secrecy performance for a cooperative diversity system with amplify-and-forward (AF) over generalized-K fading channels. More specifically, some lower bounds on the secrecy performance, such as secure outage probability (SOP), average secrecy capacity (ASC), and strictly positive secrecy capacity (SPSC), are derived in closed-form. Finally, we provide simulation results to verify the accuracy of our analytical results.

Natural maximal νμ-ντ mixing

International Nuclear Information System (INIS)

Wetterich, C.

1999-01-01

The naturalness of maximal mixing between myon- and tau-neutrinos is investigated. A spontaneously broken nonabelian generation symmetry can explain a small parameter which governs the deviation from maximal mixing. In many cases all three neutrino masses are almost degenerate. Maximal ν μ -ν τ -mixing suggests that the leading contribution to the light neutrino masses arises from the expectation value of a heavy weak triplet rather than from the seesaw mechanism. In this scenario the deviation from maximal mixing is predicted to be less than about 1%. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

Gaussian maximally multipartite-entangled states

Science.gov (United States)

Facchi, Paolo; Florio, Giuseppe; Lupo, Cosmo; Mancini, Stefano; Pascazio, Saverio

2009-12-01

We study maximally multipartite-entangled states in the context of Gaussian continuous variable quantum systems. By considering multimode Gaussian states with constrained energy, we show that perfect maximally multipartite-entangled states, which exhibit the maximum amount of bipartite entanglement for all bipartitions, only exist for systems containing n=2 or 3 modes. We further numerically investigate the structure of these states and their frustration for n≤7 .

Gaussian maximally multipartite-entangled states

International Nuclear Information System (INIS)

Facchi, Paolo; Florio, Giuseppe; Pascazio, Saverio; Lupo, Cosmo; Mancini, Stefano

2009-01-01

We study maximally multipartite-entangled states in the context of Gaussian continuous variable quantum systems. By considering multimode Gaussian states with constrained energy, we show that perfect maximally multipartite-entangled states, which exhibit the maximum amount of bipartite entanglement for all bipartitions, only exist for systems containing n=2 or 3 modes. We further numerically investigate the structure of these states and their frustration for n≤7.

Utility maximization and mode of payment

NARCIS (Netherlands)

Koning, R.H.; Ridder, G.; Heijmans, R.D.H.; Pollock, D.S.G.; Satorra, A.

2000-01-01

The implications of stochastic utility maximization in a model of choice of payment are examined. Three types of compatibility with utility maximization are distinguished: global compatibility, local compatibility on an interval, and local compatibility on a finite set of points. Keywords:

International cooperation

International Nuclear Information System (INIS)

1996-01-01

In 1995, Nuclear Regulatory Authority of the Slovak Republic (NRA SR) ensured foreign cooperation particularly in the frame of the Slovak Republic is membership in the IAEA, as well as cooperation with the Nuclear Energy Agency of the Organization for Economic Cooperation and Development (OECD NEA), cooperation with European Union in the frame of PHARE programmes, and intergovernmental cooperation and cooperation among nuclear regulatory authorities. With respect to an international importance, prestige and a wide-scope possibilities of a technical assistance , either a direct one (expert assessments, technology supplies, work placement, scientific trips, training courses) or indirect one (participation at various conferences, seminars, technical committees, etc), the most important cooperation with the IAEA in Vienna. In 1994, the Slovak Republic, was elected to the Board Governors, the represent the group of Eastern European countries. The Slovak Government entrusted the NRA SR's Chairman with representing the Slovak Republic in the Board of Governors. Owing to a good name of Slovakia was elected to the one of two Vice-Chairmen of the Board of Governors at the 882-nd session on the Board. IAEA approved and developed 8 national projects for Slovakia in 1995. Generally, IAEA is contracting scientific contracts with research institutes, nuclear power plants and other organizations. Slovak organizations used these contracts as complementary funding of their tasks. In 1995, there were 12 scientific contracts in progress, or approved respectively. Other international activities of the NRA SR, international co-operations as well as foreign affairs are reported

Diversion of drugs within health care facilities, a multiple-victim crime: patterns of diversion, scope, consequences, detection, and prevention.

Science.gov (United States)

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

2012-07-01

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. Copyright © 2012 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

ENTNEA: A concept for enhancing regional atomic energy cooperation for securing nuclear transparency in northeast Asia

Energy Technology Data Exchange (ETDEWEB)

Shin, S. T. [Korea Institute for Defence Analyses, Seoul (Korea)

2000-11-01

Nuclear energy continues to be a strong and growing component of economic development in Northeast Asia. A broad range of nuclear energy systems already exists across the region and vigorous growth is projected. Associated with these capabilities and plans are various concerns about operational safety, environmental protection, and accumulation of spent fuel and other nuclear materials. We consider cooperative measures that might address these concerns. The confidence building measures suggested here center on the sharing of information to lessen concerns about nuclear activities or to solve technical problems. These activities are encompassed by an Enhanced Nuclear Transparency in Northeast Asia (ENTNEA) concept that would be composed of near-term, information-sharing activities and an eventual regional institution. The near-term activities would address specific concerns and build a tradition of cooperation; examples include radiation measurements for public safety and emergency response, demonstration of safe operations at facilities and in transportation, and material security in the back end of the fuel cycle. Linkages to existing efforts and organizations would be sought to maximize the benefits of cooperation. In the longer term, the new cooperative tradition might evolve into an ENTNEA institution. In institutional form, ENTNEA could combine the near-term activities and new cooperative activities, which might require an institutional basis, for the mutual benefit and security of regional parties. 28 refs., 23 figs., 5 tabs. (Author)

Opportunistic Energy-Aware Amplify-and-Forward Cooperative Systems with Imperfect CSI

KAUST Repository

Amin, Osama

2015-07-29

Recently, much attention has been paid to the green design of wireless communication systems using energy efficiency (EE) metrics that should capture all energy consumption sources to deliver the required data. In this paper, we design an energyefficient relay assisted communication system based on estimated channel state information (CSI). It employs amplify-andforward relaying and switches between different communication schemes, which are known as direct-transmission, two-hop and cooperative-transmission schemes, using the estimated CSI in order to maximize the EE. Two estimation strategies are assumed, namely disintegrated channel estimation and cascaded channel estimation. To formulate an accurate EE metric for the proposed opportunistic amplify-and-forward system, the channel estimation cost is reflected on the EE metric by including its impact in the signal-to-noise ratio term and in the energy consumption during the channels estimation phase. Based on the formulated EE metric, we propose an adaptive power allocation algorithm to maximize the EE of the proposed opportunistic amplify-andforward system with channel estimation. Furthermore, we study the impact of the estimation parameters on the proposed system via simulation examples.

Developing core collections to optimize the management and the exploitation of diversity of the coffee Coffea canephora.

Science.gov (United States)

Leroy, Thierry; De Bellis, Fabien; Legnate, Hyacinthe; Musoli, Pascal; Kalonji, Adrien; Loor Solórzano, Rey Gastón; Cubry, Philippe

2014-06-01

The management of diversity for conservation and breeding is of great importance for all plant species and is particularly true in perennial species, such as the coffee Coffea canephora. This species exhibits a large genetic and phenotypic diversity with six different diversity groups. Large field collections are available in the Ivory Coast, Uganda and other Asian, American and African countries but are very expensive and time consuming to establish and maintain in large areas. We propose to improve coffee germplasm management through the construction of genetic core collections derived from a set of 565 accessions that are characterized with 13 microsatellite markers. Core collections of 12, 24 and 48 accessions were defined using two methods aimed to maximize the allelic diversity (Maximization strategy) or genetic distance (Maximum-Length Sub-Tree method). A composite core collection of 77 accessions is proposed for both objectives of an optimal management of diversity and breeding. This core collection presents a gene diversity value of 0.8 and exhibits the totality of the major alleles (i.e., 184) that are present in the initial set. The seven proposed core collections constitute a valuable tool for diversity management and a foundation for breeding programs. The use of these collections for collection management in research centers and breeding perspectives for coffee improvement are discussed.

Activity versus outcome maximization in time management.

Science.gov (United States)

Malkoc, Selin A; Tonietto, Gabriela N

2018-04-30

Feeling time-pressed has become ubiquitous. Time management strategies have emerged to help individuals fit in more of their desired and necessary activities. We provide a review of these strategies. In doing so, we distinguish between two, often competing, motives people have in managing their time: activity maximization and outcome maximization. The emerging literature points to an important dilemma: a given strategy that maximizes the number of activities might be detrimental to outcome maximization. We discuss such factors that might hinder performance in work tasks and enjoyment in leisure tasks. Finally, we provide theoretically grounded recommendations that can help balance these two important goals in time management. Published by Elsevier Ltd.

Birth order and preschool children's cooperative abilities: A within-family analysis.

Science.gov (United States)

Prime, Heather; Plamondon, André; Jenkins, Jennifer M

2017-09-01

There is evidence for a laterborn sibling advantage in some social skills, although this has not been investigated in children's early capacities for cooperation. Using a within-family design, this study compared firstborn and laterborn (i.e., middle and youngest) siblings on their cooperative abilities when they were aged around 3 years. Further, the study investigated whether the association between children's birth order and cooperative abilities was dependent on the prosocial behaviour of other siblings in the home. The sample included 288 ethnically and sociodemographically diverse children clustered within 144 families. Cooperation was directly assessed using a problem-solving paradigm requiring two simultaneous and complementary actions of the child and adult tester to achieve a joint goal. Parents reported on the prosocial behaviour of up to four siblings in the home. Results of a multilevel analysis indicated that youngest children were more advanced in their cooperative abilities, compared to firstborn children, irrespective of their siblings' prosociality. Middle children, in contrast, were only advantaged over firstborn children if their siblings showed high levels of prosociality. The analysis accounted for a number of potential family-wide confounds, providing evidence that this is a child-specific effect related to birth order. Findings are discussed from a social constructivist perspective with an emphasis on the sibling relationship as a context for cooperative interactions that facilitate sociocognitive development. Statement of contribution What is already known on this subject? There are individual differences in children's early capacities for cooperation. Children's early cooperation has not been considered in relation to birth order and/or sibling interaction quality. What does this study add? Youngest children are advantaged in their cooperation as compared to firstborn children. Middle children are also advantaged, but only if their

Strengthening the infrastructure for RI applications in cooperation with the IAEA

Energy Technology Data Exchange (ETDEWEB)

Park, Kyung Bae; Hong, Young Don; Kim, Seung Yun; Kim, Kyoung Pyo; Lee, Jeong Kong

2000-12-01

The future direction for nuclear cooperation should be implemented with the aim of enhancing the status of Korea within the international society as well as carrying out the established national nuclear policy goal. Strategies for implementing cooperation with the IAEA were described into four separate parts; 'strategies for strengthening cooperation in general areas', 'strategies for implementing IAEA technical cooperation programs', 'strategies for implementing IAEA CRP programs' and 'Strategies for effective participation in the area of radiation and RI application'. As for strategies for implementing IAEA technical cooperation programs, i) expanding domestic personnel's entering into the IAEA ii) establishment of a liaison office for support of IAEA technical cooperation iii) expanding domestic experts entering into member of consultation group for a director-general of the IAEA and more participation in the international meetings iv) cooperation with IAEA's Seibersdorf Laboratories. For the strengthening of IAEA technical cooperation, strategies for effective implementation of technical cooperation programs such as i) strengthening role of national TC liaison officer ii) strengthening application of Model Project concept iii) Implementing End-user oriented programs iv) Establishment of measure to increase the TC implementation rate v) hosting of fellowship, scientific visitors, support for expert mission, were presented. Strategies for expanding domestic participation in the IAEA technical cooperation programs were also described for producing the benefits from implementing the IAEA technical cooperation programs. As for strategies for implementing the IAEA CRP programs, i) measures for active participation in the IAEA CRP programs and ii) measures for gradual participation in the IAEA CRP programs were separately described. To maximize the utilization of HANARO, a multi-purpose research reactor, the on

Strengthening the infrastructure for RI applications in cooperation with the IAEA

International Nuclear Information System (INIS)

Park, Kyung Bae; Hong, Young Don; Kim, Seung Yun; Kim, Kyoung Pyo; Lee, Jeong Kong

2000-12-01

The future direction for nuclear cooperation should be implemented with the aim of enhancing the status of Korea within the international society as well as carrying out the established national nuclear policy goal. Strategies for implementing cooperation with the IAEA were described into four separate parts; 'strategies for strengthening cooperation in general areas', 'strategies for implementing IAEA technical cooperation programs', 'strategies for implementing IAEA CRP programs' and 'Strategies for effective participation in the area of radiation and RI application'. As for strategies for implementing IAEA technical cooperation programs, i) expanding domestic personnel's entering into the IAEA ii) establishment of a liaison office for support of IAEA technical cooperation iii) expanding domestic experts entering into member of consultation group for a director-general of the IAEA and more participation in the international meetings iv) cooperation with IAEA's Seibersdorf Laboratories. For the strengthening of IAEA technical cooperation, strategies for effective implementation of technical cooperation programs such as i) strengthening role of national TC liaison officer ii) strengthening application of Model Project concept iii) Implementing End-user oriented programs iv) Establishment of measure to increase the TC implementation rate v) hosting of fellowship, scientific visitors, support for expert mission, were presented. Strategies for expanding domestic participation in the IAEA technical cooperation programs were also described for producing the benefits from implementing the IAEA technical cooperation programs. As for strategies for implementing the IAEA CRP programs, i) measures for active participation in the IAEA CRP programs and ii) measures for gradual participation in the IAEA CRP programs were separately described. To maximize the utilization of HANARO, a multi-purpose research reactor, the on-going development and development project are actively

Technical Co-operation Report for 1996. Report by the Director General

International Nuclear Information System (INIS)

1997-01-01

The Agency's Technical Cooperation (TC) Programme made further progress during 1996 in implementing recent initiatives to strengthen efficiency and effectiveness. These initiatives seek to maximize the developmental contribution of counterpart institutions by emphasizing the management of technology to solve social and economic problems. The new direction has been embodied in the term ''Partners in Development''. The Partners in Development approach is reflected in last year's Report to the Board of Governors and the General Conference on Strengthening of the Agency's Technical Co-operation Activities, which provided an update on ongoing activities and elaborated new initiatives. The 1995 Technical Cooperation Report focused on the progress in implementing these initiatives. Next year, the Secretariat plans to combine the TC Report with the Report on Strengthening of the Agency's Technical Co-operation Activities in order to improve the clarity, consistency and economy of these presentations. Establishing a development partnership with Member States is the central goal of a new Strategy for TC. The refinement of this strategy required considerable effort during 1996, when the process first began to define objectives, targets and the means of accomplishing them. Alongside internal consultations, the role of SAGTAC became instrumental in reaching consensus on the main elements of the strategy. Future efforts include the formulation of implementation plans for the strategy. Once completed, the strategy will be presented to the TACC and Board in 1997. Reflecting these developments, section A of this Report presents the basic features of the TC Strategy, and the approach to be taken to achieve its objectives. The Strategy addresses among others the recommendations contained in resolution GC(40)/RES/13 on the Strengthening of Technical Co-operation: activities to improve the scientific and technological capabilities of developing countries; to achieve sustainable

Cooperative joint precoding in a downlink cellular system with shared relay: Design and performance evaluation

KAUST Repository

Kwon, JaeWoo; Park, Kihong; Ko, Youngchai; Yang, Hongchuan

2012-01-01

In this paper, we investigate a relay enhanced cellular system, where a relay station is located in the overlap area served by two base stations. We propose cooperative joint precoding schemes for the downlink transmission of such relay enhanced cellular system to maximize the system capacity while minimizing the interference at both the relay station and the mobile stations. We formulate the optimization problems to maximize the system capacity and design the multiuser precoding vectors at each base station and the relay station. We quantify the ergodic rate performance of the proposed multiuser precoding schemes through statistical analysis. The extensively derived ergodic expressions will facilitate the accurate performance evaluation of the proposed transmission schemes. Numerical results show that the proposed schemes can effectively cancel the interference and improve the sum rate and the outage performance for cell edge users. © 2002-2012 IEEE.

Cooperative joint precoding in a downlink cellular system with shared relay: Design and performance evaluation

KAUST Repository

Kwon, JaeWoo

2012-10-01

In this paper, we investigate a relay enhanced cellular system, where a relay station is located in the overlap area served by two base stations. We propose cooperative joint precoding schemes for the downlink transmission of such relay enhanced cellular system to maximize the system capacity while minimizing the interference at both the relay station and the mobile stations. We formulate the optimization problems to maximize the system capacity and design the multiuser precoding vectors at each base station and the relay station. We quantify the ergodic rate performance of the proposed multiuser precoding schemes through statistical analysis. The extensively derived ergodic expressions will facilitate the accurate performance evaluation of the proposed transmission schemes. Numerical results show that the proposed schemes can effectively cancel the interference and improve the sum rate and the outage performance for cell edge users. © 2002-2012 IEEE.

Multicell Cooperation for LTE-Advanced Heterogeneous Network Scenarios

DEFF Research Database (Denmark)

Soret, Beatriz; Wang, Hua; Rosa, Claudio

2013-01-01

In this article we present two promising practical use cases for simple multicell cooperation for LTE-Advanced heterogeneous network (HetNet) scenarios with macro and small cells. For co-channel deployment cases, we recommend the use of enhanced inter-cell interference coordination (e......ICIC) to mitigate cross-tier interference and ensure sufficient offload of users from macro to small cells. It is shown how the eICIC benefit is maximized by using a distributed inter-base station control framework for dynamic adjustment of essential parameters. Secondly, for scenarios where macro and small cells...... are deployed at different carriers an efficient use of the fragmented spectrum can be achieved by using collaborative inter-site carrier aggregation. In addition to distributed coordination/collaboration between base station nodes, the importance of explicit terminal assistance is highlighted. Comprehensive...

International cooperation

International Nuclear Information System (INIS)

Prieto, F.E.

1984-01-01

It looks doubtless that the need for an international cooperation to solve the worldwide energy problems is already a concern of individuals, institutions, and governments. This is an improvement. But there is something lacking. The author refers to the Atoms for Peace speech, the origin of the IAEA and of the subsequent spreading of the nuclear option. He also refers back to the call made by the Mexican government for a worldwide energy cooperation. He stresses the need for governments to cooperate, so that this international cooperation on energy can be put into operation for the benefit of mankind

A game theoretical approach for cooperative green mobile operators under roaming price consideration

KAUST Repository

Ghazzai, Hakim

2015-09-11

In this paper, we investigate the performance of a green mobile operator collaborating with other traditional mobile operators. Its goal is to minimize its CO2 emissions, maximize its profit or achieve or tradeoff between both objectives by offloading its users to neighbor networks and exploiting renewable energies. On the other hand, traditional mobile operators aim to maximize their profits by attracting the maximum number of roamed users. The problem is modeled as a two-level Stackelberg game and its equilibrium is derived. A green mobile operator level that determines how many users per each base station to offload to each neighbor network, and a non-green mobile operator level where operators focus on finding the optimal roaming price. Our simulation results show a significant saving in terms of CO2 emissions compared to the non-cooperation case and that roaming decision depends essentially on the availability of renewable energy in base station sites. © 2015 IEEE.

Cooperation for a competitive position: The impact of hospital cooperation behavior on organizational performance.

Science.gov (United States)

Büchner, Vera Antonia; Hinz, Vera; Schreyögg, Jonas

2015-01-01

Several public policy initiatives, particularly those involving managed care, aim to enhance cooperation between partners in the health care sector because it is expected that such cooperation will reduce costs and generate additional revenue. However, empirical evidence regarding the effects of cooperation on hospital performance is scarce, particularly with respect to creating a comprehensive measure of cooperation behavior. The aim of this study is to investigate the impact of hospital cooperation behavior on organizational performance. We differentiate between horizontal and vertical cooperation using two alternative measures-cooperation depth and cooperation breadth-and include the interaction effects between both cooperation directions. Data are derived from a survey of German hospitals and combined with objective performance information from annual financial statements. Generalized linear regression models are used. The study findings provide insight into the nature of hospitals' cooperation behavior. In particular, we show that there are negative synergies between horizontal administrative cooperation behavior and vertical cooperation behavior. Whereas the depth and breadth of horizontal administrative cooperation positively affect financial performance (when there is no vertical cooperation), vertical cooperation positively affects financial performance (when there is no horizontal administrative cooperation) only when cooperation is broad (rather than deep). Horizontal cooperation is generally more effective than vertical cooperation at improving financial performance. Hospital managers should consider the negative interaction effect when making decisions about whether to recommend a cooperative relationship in a horizontal or vertical direction. In addition, managers should be aware of the limited financial benefit of cooperation behavior.

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

Science.gov (United States)

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…

Maximizing Entropy over Markov Processes

DEFF Research Database (Denmark)

Biondi, Fabrizio; Legay, Axel; Nielsen, Bo Friis

2013-01-01

The channel capacity of a deterministic system with confidential data is an upper bound on the amount of bits of data an attacker can learn from the system. We encode all possible attacks to a system using a probabilistic specification, an Interval Markov Chain. Then the channel capacity...... as a reward function, a polynomial algorithm to verify the existence of an system maximizing entropy among those respecting a specification, a procedure for the maximization of reward functions over Interval Markov Chains and its application to synthesize an implementation maximizing entropy. We show how...... to use Interval Markov Chains to model abstractions of deterministic systems with confidential data, and use the above results to compute their channel capacity. These results are a foundation for ongoing work on computing channel capacity for abstractions of programs derived from code....

Maximizing entropy over Markov processes

DEFF Research Database (Denmark)

Biondi, Fabrizio; Legay, Axel; Nielsen, Bo Friis

2014-01-01

The channel capacity of a deterministic system with confidential data is an upper bound on the amount of bits of data an attacker can learn from the system. We encode all possible attacks to a system using a probabilistic specification, an Interval Markov Chain. Then the channel capacity...... as a reward function, a polynomial algorithm to verify the existence of a system maximizing entropy among those respecting a specification, a procedure for the maximization of reward functions over Interval Markov Chains and its application to synthesize an implementation maximizing entropy. We show how...... to use Interval Markov Chains to model abstractions of deterministic systems with confidential data, and use the above results to compute their channel capacity. These results are a foundation for ongoing work on computing channel capacity for abstractions of programs derived from code. © 2014 Elsevier...

Go High or Go Low? Adaptive Evolution of High and Low Relatedness Societies in Social Hymenoptera

Directory of Open Access Journals (Sweden)

Peter Nonacs

2017-08-01

Full Text Available Cooperative groups can increase fitness either by helping kin or interacting with unlike individuals to produce social heterosis. They cannot, however, simultaneously maximize both benefits. This tradeoff between nepotism and diversity is modeled using Hamilton's rule (rb–c > 0, by allowing benefit and cost to be dynamic functions of relatedness (i.e., social heterosis predicts b and c depend on r. Simulations show that evolutionary outcomes tend to maximize either nepotism (with high genetic relatedness, or social heterosis (with low relatedness rather than produce an intermediate outcome. Although genetic diversity can arise through multiple mating, a second possible mechanism—the exchanging of individuals across groups—is similarly effective. Such worker “drifting” is common in many species of social Hymenoptera and may be a form of indirect reciprocity. Drifting individuals increase an unrelated group's productivity by enhancing its genetic diversity, with this effect being reciprocated by other unrelated drifters entering their natal group. The benefits from social heterosis and indirect reciprocity are robust against cheating and show that it is possible to evolve stable cooperation between individuals that are genetically distant or unrelated. As drifting becomes more prevalent colony boundaries may become weakly discriminated, which may predispose toward the evolution of unicoloniality in some species.

HEALTH INSURANCE: CONTRIBUTIONS AND REIMBURSEMENT MAXIMAL

CERN Document Server

HR Division

2000-01-01

Affected by both the salary adjustment index on 1.1.2000 and the evolution of the staff members and fellows population, the average reference salary, which is used as an index for fixed contributions and reimbursement maximal, has changed significantly. An adjustment of the amounts of the reimbursement maximal and the fixed contributions is therefore necessary, as from 1 January 2000.Reimbursement maximalThe revised reimbursement maximal will appear on the leaflet summarising the benefits for the year 2000, which will soon be available from the divisional secretariats and from the AUSTRIA office at CERN.Fixed contributionsThe fixed contributions, applicable to some categories of voluntarily insured persons, are set as follows (amounts in CHF for monthly contributions):voluntarily insured member of the personnel, with complete coverage:815,- (was 803,- in 1999)voluntarily insured member of the personnel, with reduced coverage:407,- (was 402,- in 1999)voluntarily insured no longer dependent child:326,- (was 321...

Choosing the cooperative option

Energy Technology Data Exchange (ETDEWEB)

English, G. (National Rural Electric Cooperative Association (United States))

1999-06-01

Cooperatives do not ask to be exempted from the law. They do ask that laws and regulations be designed to allow them to meet the needs of their consumer-owners in accordance with cooperative principles, at a time that the marginal consumers being abandoned by for-profit utilities may be ready to gravitate toward cooperatives. The cooperative principles are worth reviewing because they explain the focus on the consumer and the cooperative concept of service: cooperatives are voluntary organizations, open to all persons able to use their services and willing to accept the responsibilities of membership; cooperatives are democratic organizations controlled by their members, who actively participate in setting policies and making decisions, the elected representatives are accountable to the membership; members contribute equitably to, and democratically control, the capital of their cooperative; cooperatives are autonomous, self-help organizations controlled by their members, if they enter into agreements with other organizations, including governments, they do so on terms that ensure democratic control by their members and maintain their cooperative autonomy; cooperatives provide education and training for their members, elected representatives, managers, and employees so they can contribute effectively to the development of their cooperatives, they inform the general public, particularly young people and opinion leaders, about the nature and benefits of cooperation; cooperatives serve their members most effectively and strength the cooperative movement by working together through local, national, regional, and international structures; and while focusing on member needs, cooperatives work for the sustainable development of their communities through policies accepted by their members.

Determination of a Screening Metric for High Diversity DNA Libraries.

Science.gov (United States)

Guido, Nicholas J; Handerson, Steven; Joseph, Elaine M; Leake, Devin; Kung, Li A

2016-01-01

The fields of antibody engineering, enzyme optimization and pathway construction rely increasingly on screening complex variant DNA libraries. These highly diverse libraries allow researchers to sample a maximized sequence space; and therefore, more rapidly identify proteins with significantly improved activity. The current state of the art in synthetic biology allows for libraries with billions of variants, pushing the limits of researchers' ability to qualify libraries for screening by measuring the traditional quality metrics of fidelity and diversity of variants. Instead, when screening variant libraries, researchers typically use a generic, and often insufficient, oversampling rate based on a common rule-of-thumb. We have developed methods to calculate a library-specific oversampling metric, based on fidelity, diversity, and representation of variants, which informs researchers, prior to screening the library, of the amount of oversampling required to ensure that the desired fraction of variant molecules will be sampled. To derive this oversampling metric, we developed a novel alignment tool to efficiently measure frequency counts of individual nucleotide variant positions using next-generation sequencing data. Next, we apply a method based on the "coupon collector" probability theory to construct a curve of upper bound estimates of the sampling size required for any desired variant coverage. The calculated oversampling metric will guide researchers to maximize their efficiency in using highly variant libraries.

Determination of a Screening Metric for High Diversity DNA Libraries.

Directory of Open Access Journals (Sweden)

Nicholas J Guido

Full Text Available The fields of antibody engineering, enzyme optimization and pathway construction rely increasingly on screening complex variant DNA libraries. These highly diverse libraries allow researchers to sample a maximized sequence space; and therefore, more rapidly identify proteins with significantly improved activity. The current state of the art in synthetic biology allows for libraries with billions of variants, pushing the limits of researchers' ability to qualify libraries for screening by measuring the traditional quality metrics of fidelity and diversity of variants. Instead, when screening variant libraries, researchers typically use a generic, and often insufficient, oversampling rate based on a common rule-of-thumb. We have developed methods to calculate a library-specific oversampling metric, based on fidelity, diversity, and representation of variants, which informs researchers, prior to screening the library, of the amount of oversampling required to ensure that the desired fraction of variant molecules will be sampled. To derive this oversampling metric, we developed a novel alignment tool to efficiently measure frequency counts of individual nucleotide variant positions using next-generation sequencing data. Next, we apply a method based on the "coupon collector" probability theory to construct a curve of upper bound estimates of the sampling size required for any desired variant coverage. The calculated oversampling metric will guide researchers to maximize their efficiency in using highly variant libraries.

On the maximal diphoton width

CERN Document Server

Salvio, Alberto; Strumia, Alessandro; Urbano, Alfredo

2016-01-01

Motivated by the 750 GeV diphoton excess found at LHC, we compute the maximal width into $\\gamma\\gamma$ that a neutral scalar can acquire through a loop of charged fermions or scalars as function of the maximal scale at which the theory holds, taking into account vacuum (meta)stability bounds. We show how an extra gauge symmetry can qualitatively weaken such bounds, and explore collider probes and connections with Dark Matter.

Exploiting Multi-user Diversity and Multi-hop Diversity in Dual-hop Broadcast Channels

KAUST Repository

Zafar, Ammar

2013-05-21

We propose joint user-and-hop scheduling over dual-hop block-fading broadcast channels in order to exploit multi-user diversity gains and multi-hop diversity gains all together. To achieve this objective, the first and second hops are scheduled opportunistically based on the channel state information. The joint scheduling problem is formulated as maximizing the weighted sum of the long term achievable rates of the users under a stability constraint, which means that in the long term the rate received by the relay should equal the rate transmitted by it, in addition to power constraints. We show that this problem is equivalent to a single-hop broadcast channel by treating the source as a virtual user with an optimal weight that maintains the stability constraint. We show how to obtain the source weight either off-line based on channel statistics or on real-time based on channel measurements. Furthermore, we consider special cases including the maximum sum-rate scheduler and the proportional fair scheduler. We also show how to extend the scheme into one that allows multiple user scheduling via superposition coding with successive decoding. Numerical results demonstrate that our proposed joint scheduling scheme enlarges the rate region as compared to scheduling schemes that exploit the diversity gains partially.

International co-operation

International Nuclear Information System (INIS)

1998-01-01

In this part the are reviewed: Co-operation with IAEA; Participation of the Slovakia on the 41 st session of the General Conference; The comprehensive Nuclear-Test-Ban Treaty Organization; Co-operation with the Organization for Economic Co-operation and Development; co-operation with the European Commission; Fulfillment of obligations resulting from the international contracting documents

Energy Profile and Perspectives on Northeast Asian Energy Co-operation of North Korea

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-06-01

Energy policy of North Korea is basically based on the 'Principle of Self-reliance'. Throughout the active development of domestic energy sources, North Korea try to maximize the energy self-reliance as well as to minimize the outflow of currency for the import of energy. But, the 'Principle of Self-reliance' of energy sector brought about the excess dependency on coal and hydro, and eventually causes the contraction of oil and natural gas consumption. This kind of adverse reaction of the 'Principle of Self-reliance' is the major reason of overall weakness of national-wide economic system. It is not known actually what kinds of perspectives North Korea has on the Northeast Asian energy cooperation. But, it can be said that Northeast Asian energy cooperation can be the best chance for North Korea to solve current energy crisis and to transfer the economic system to capitalism for the recovery of national economy. 19 refs., 4 figs., 9 tabs.

Diversity management in the workplace: beyond compliance

Directory of Open Access Journals (Sweden)

N.S. Gwele

2009-09-01

Full Text Available Diversity management is not a numbers game. Diversity management is a holistic and strategic intervention aimed at maximizing every individual’s potential to contribute towards the realization o f the organization’s goals through capitalizing on individual talents and differences within a diverse workforce environment. Managing interpersonal relationships within a diverse workforce environment presents a number of challenges related to changes in the social, legal and economic landscape, individual expectations and values as well as the inevitable change in organizational culture (Chartered Institute of Personnel and Development 2005: 1-7. Whether or not organizations are effective in managing diversity is a function of senior managements’ commitment, and the perceived centrality of diversity management by all those who populate the institution’s workspace. Above all it should be clear to all employees, irrespective of race, gender, or vocational/professional status, that each and every one of them has something of value to contribute towards the realization of the institution’s mission and goals. It is crucial to determine clear and manageable success indicators, focusing not only on compliance with legal obligations to include and/or increase the number of employees from the underrepresented and designated groups, but also on strategic intervention strategies to be used to promote and nurture individual talent and potential toward the realization of both individual aspirations and organizational goals re-quality patient outcomes.

Mechanisms and dynamics of cooperation and competition emergence in complex networked systems

Science.gov (United States)

Gianetto, David A.

Cooperative behavior is a pervasive phenomenon in human interactions and yet how it can evolve and become established, through the selfish process of natural selection, is an enduring puzzle. These behaviors emerge when agents interact in a structured manner; even so, the key structural factors that affect cooperation are not well understood. Moreover, the literature often considers cooperation a single attribute of primitive agents who do not react to environmental changes but real-world actors are more perceptive. The present work moves beyond these assumptions by evolving more realistic game participants, with memories of the past, on complex networks. Agents play repeated games with a three-part Markovian strategy that allows us to separate the cooperation phenomenon into trust, reciprocity, and forgiveness characteristics. Our results show that networks matter most when agents gain the most by acting in a selfish manner, irrespective of how much they may lose by cooperating; since the context provided by neighborhoods inhibits greedy impulses that agents otherwise succumb to in isolation. Network modularity is the most important driver of cooperation emergence in these high-stakes games. However, modularity fails to tell the complete story. Modular scale-free graphs impede cooperation when close coordination is required, partially due to the acyclic nature of scale-free network models. To achieve the highest cooperation in diverse social conditions, both high modularity, low connectivity within modules, and a rich network of long cycles become important. With these findings in hand, we study the influence of networks on coordination and competition within the federal health care insurance exchange. In this applied study, we show that systemic health care coordination is encouraged by the emergent insurance network. The network helps underpin the viability of the exchange and provides an environment of stronger competition once a critical-mass of insurers have

GPs' experiences with out-of-hours GP cooperatives: a survey study from the Netherlands.

Science.gov (United States)

Smits, Marleen; Keizer, Ellen; Huibers, Linda; Giesen, Paul

2014-09-01

Out-of-hours primary care has been provided by general practitioner (GP) cooperatives since the year 2000 in the Netherlands. Early studies in countries with similar organizational structures showed positive GP experiences. However, nowadays it is said that GPs experience a high workload at the cooperative and that they outsource a considerable part of their shifts. To examine positive and negative experiences of GPs providing out-of-hours primary care, and the frequency and reasons for outsourcing shifts. A cross-sectional observational survey among 688 GPs connected to six GP cooperatives in the Netherlands, using a web-based questionnaire. The response was 55% (n = 378). The main reasons for working in GP cooperatives were to retain registration as GP (79%) and remain experienced in acute care (74%). GPs considered the peak hours (81%) and the high number of patients (73%) as the most negative aspects. Most GPs chose to provide the out-of-hours shifts themselves: 85% outsourced maximally 25% of their shifts. The percentage of outsourced shifts increased with age. Main reasons for outsourcing were the desire to have more private time (76%); the high workload in daytime practice (71%); and less the workload during out-of-hours (46%). GPs are motivated to work in out-of-hours GP cooperatives, and they outsource few shifts. GPs consider the peak load and the large number of (non-urgent) help requests as the most negative aspects. To motivate and involve GPs for 7 × 24-h primary care, it is important to set limits on their workload.

Exact performance of cooperative spectrum sensing for cognitive radios with quantized information under imperfect reporting channels

KAUST Repository

Ben Ghorbel, Mahdi

2013-09-01

Spectrum sensing is the first and main step for cognitive radio systems to achieve an efficient use of the spectrum. Cooperation among cognitive radio users is a technique employed to improve the sensing performance by exploiting the diversity between the sensing channels to overcome the fading and shadowing effects which allows reduction of miss-detection and false alarm probabilities. Information can be exchanged between cooperating users in different formats from the binary hard information to the full soft information. Quantized information has shown its efficiency as a trade-off between binary hard and full soft for other cooperative schemes, in this paper, we investigate the use of quantized information between cooperating cognitive users. We derive closed-form expressions of the cooperative average false alarm and detection probabilities over fading channels for a generalized system model with not necessarily identical average sensing Signal-to-Noise Ratio (SNR) and imperfect reporting channels. Numerical simulations allow us to conclude a tradeoff between the quantization size and the reporting energy in order to achieve the optimal cooperative error probability. Copyright © 2013 by the Institute of Electrical and Electronic Engineers, Inc.

HSF and Msn2/4p can exclusively or cooperatively activate the yeast HSP104 gene.

Science.gov (United States)

Grably, Melanie R; Stanhill, Ariel; Tell, Osnat; Engelberg, David

2002-04-01

In an effort to understand how an accurate level of stress-specific expression is obtained, we studied the promoter of the yeast HSP104 gene. Through 5' deletions, we defined a 334 bp fragment upstream of the first coding AUG as sufficient and essential for maximal basal activity and a 260 bp fragment as sufficient and essential for heat shock responsiveness. These sequences contain heat shock elements (HSEs) and stress response elements (STREs) that cooperate to achieve maximal inducible expression. However, in the absence of one set of factors (e.g. in msn2Deltamsn4Delta cells) proper induction is obtained exclusively through HSEs. We also show that HSP104 is constitutively derepressed in ras2Delta cells. This derepression is achieved exclusively through activation of STREs, with no role for HSEs. Strikingly, in ras2Deltamsn2Deltamsn4Delta cells the HSP104 promoter is also derepressed, but in this strain derepression is mediated through HSEs, showing the flexibility and adaptation of the promoter. Thus, appropriate transcription of HSP104 is usually obtained through cooperation between the Msn2/4/STRE and the HSF/ HSE systems, but each factor could activate the promoter alone, backing up the other. Transcription control of HSP104 is adaptive and robust, ensuring proper expression under extreme conditions and in various mutants.

Pervasive Selection for Cooperative Cross-Feeding in Bacterial Communities.

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Sebastian Germerodt

2016-06-01

Full Text Available 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.

Fostering group identification and creativity in diverse groups: the role of individuation and self-verification.

Science.gov (United States)

Swann, William B; Kwan, Virginia S Y; Polzer, Jeffrey T; Milton, Laurie P

2003-11-01

A longitudinal study examined the interplay of identity negotiation processes and diversity in small groups of master's of business administration (MBA) students. When perceivers formed relatively positive impressions of other group members, higher diversity predicted more individuation of targets. When perceivers formed relatively neutral impressions of other group members, however, higher diversity predicted less individuation of targets. Individuation at the outset of the semester predicted self-verification effects several weeks later, and self-verification, in turn, predicted group identification and creative task performance. The authors conclude that contrary to self-categorization theory, fostering individuation and self-verification in diverse groups may maximize group identification and productivity.

Sorting and sustaining cooperation

DEFF Research Database (Denmark)

Vikander, Nick

2013-01-01

This paper looks at cooperation in teams where some people are selfish and others are conditional cooperators, and where lay-offs will occur at a fixed future date. I show that the best way to sustain cooperation prior to the lay-offs is often in a sorting equilibrium, where conditional cooperators...... can identify and then work with one another. Changes to parameters that would seem to make cooperation more attractive, such as an increase in the discount factor or the fraction of conditional cooperators, can reduce equilibrium cooperation if they decrease a selfish player's incentive to sort....

Egalitarism of the prenucleolus for cooperative games

Energy Technology Data Exchange (ETDEWEB)

Driessen, T.

1994-12-31

The prenucleolus is a well-known solution concept for cooperative games in characteristic function form which is always contained in the prekernel. In fact, the prenucleolus concept is based on the idea of excess. The current paper examines the set of efficient payoff vectors in an n person game which attain their maximal excesses at the (n {minus} 2)-person coalitions. It is established that, under a certain condition on the worth of (n {minus} 2)-person coalitions in the n-person game, the intersection of the relevant set with the prekernel is either empty or a singleton. A description of that single point is provided in terms of the egalitarian division of the remaining total worth, given that each player is already paid a special kind of an average of the player`s contributions with respect to (n {minus} 2)-person coalitions. The latter division rule is called the egalitarian non-average contribution (ENAC)-method. The main purpose of the paper is to present conditions on the game to guarantee that the ENAC-method agrees with the prenucleolus concept. The main sufficient condition expresses that the maximal excesses at the ENAC solution in the n-person game are determined by the (n {minus} 2)-person coalitions. A reformulation of the main sufficient condition in terms of the data of the game itself is added. Finally three types of conditions which are stronger than the main sufficient condition, are listed.

Energy Cooperation in Ultradense Network Powered by Renewable Energy Based on Cluster and Learning Strategy

Directory of Open Access Journals (Sweden)

Chunhong Duo

2017-01-01

Full Text Available A new method about renewable energy cooperation among small base stations (SBSs is proposed, which is for maximizing the energy efficiency in ultradense network (UDN. In UDN each SBS is equipped with energy harvesting (EH unit, and the energy arrival times are modeled as a Poisson counting process. Firstly, SBSs of large traffic demands are selected as the clustering centers, and then all SBSs are clustered using dynamic k-means algorithm. Secondly, SBSs coordinate their renewable energy within each formed cluster. The process of energy cooperation among SBSs is considered as Markov decision process. Q-learning algorithm is utilized to optimize energy cooperation. In the algorithm there are four different actions and their corresponding reward functions. Q-learning explores the action as much as possible and predicts better action by calculating reward. In addition, ε greedy policy is used to ensure the algorithm convergence. Finally, simulation results show that the new method reduces data dimension and improves calculation speed, which furthermore improves the utilization of renewable energy and promotes the performance of UDN. Through online optimization, the proposed method can significantly improve the energy utilization rate and data transmission rate.

The Role of Vietnam in The ASEAN Regional Security Cooperation: From Mechanism Construction to Dispute Settlement

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Li Chunxia

2016-12-01

Full Text Available In the context of the integration of ASEAN, Vietnam recognized that the strategic role of ASEAN is in its diplomacy. At the same time, to further improve the status in the region and in the international community, Vietnam has actively been participating in ASEAN affairs. Vietnam not only promoted the integration process of ASEAN, but also promoted the political security cooperation of ASEAN, in which Vietnam has advantages and wants to play a leading role. On the one hand, Vietnam promotes the construction of political security cooperation mechanisms, such as ARF, ADMM+, and so on; on the other hand, Vietnam took the South China Sea as a common concern, actively appeals for a common ASEAN position, to maximize its own benefit. Vietnam will further enhance and consolidate its status and role in ASEAN in the future.

Cooperatives as Entrants

OpenAIRE

Richard J. Sexton; Terri A. Sexton

1987-01-01

A potential shortcoming of game-theoretic models in industrial organization is their failure to consider consumers as players. We introduce a customer coalition --- a cooperative -- as a potential entrant and compare the cooperative entry threat with that posed by the usual for-profit entrant. We identify four fundamental distinctions between cooperative and for-profit entrants and demonstrate that the strategic interplay between a cooperative and an incumbent firm may differ markedly from th...

The Cooperatives of Second Degree in the Cuban Agricultural System and the paper of the Marketing of Relationship

Directory of Open Access Journals (Sweden)

Juan Carlos Prego Regalado

2015-12-01

Full Text Available The cooperative movement in Cuba extends quickly to diverse sectors of the national economy and he/she consolidates in the agricultural sector with a great impact in the society, it will demand it the constitution of cooperative of second degree, with the purpose of elevating the integration of the productive chains of the agricultural system. The present work has for objective to deepen in the paper of the cooperatives of second degree in the Cuban agricultural system, as well as in the relationship marketing like a tool that it stimulates the articulation of the bond among the cooperatives of first and second degree with attachment to the principles of the cooperativism and moderated to the characteristics, conditions and peculiarities in the context of the process of Bring up to date of the Cuban Economic Pattern.

A Criterion to Identify Maximally Entangled Four-Qubit State

International Nuclear Information System (INIS)

Zha Xinwei; Song Haiyang; Feng Feng

2011-01-01

Paolo Facchi, et al. [Phys. Rev. A 77 (2008) 060304(R)] presented a maximally multipartite entangled state (MMES). Here, we give a criterion for the identification of maximally entangled four-qubit states. Using this criterion, we not only identify some existing maximally entangled four-qubit states in the literature, but also find several new maximally entangled four-qubit states as well. (general)

Environmental monitoring and cooperative resource management at the WIPP site

International Nuclear Information System (INIS)

1992-01-01

This poster session by the Environmental Monitoring Section of the US DOE Waste Isolation Pilot Plant is to demonstrate that the DOE is committed to sound environmental management. This WIPP poster session demonstrates radiological as well as nonradiological environmental monitoring activities conducted routinely at the WIPP. And how data collected prior to the WIPP being operational is used to establish a preoperational baseline for environmental studies in which the samples collected during the operational phase will be compared. Cooperative Resource Management is a relatively new concept for governments agencies. It allows two or more agencies the ability to jointly share in funding a program or project and yet both agencies can benefit from the outcome. These programs are usually a biological type study. The WIPP cooperative agreement between the US BLM, DOE and its contractors is to continue the ongoing documentation of the diversity of the Chihuahuan desert

The knowledge absorptive capacity to improve the cooperation and innovation in the firm

Directory of Open Access Journals (Sweden)

Lourdes Saiz

2018-04-01

Full Text Available Purpose: The purpose of this paper is to study the absorptive capacity types in the knowledge management literature and aims to understand how companies can strength their contexts of cooperation in order to innovate. Design/methodology/approach: A balanced panel of 1,220 firms that respond to the Survey of Business Strategies for a three-year period was used, which represents a total of 3,660 observations.   Findings: The justification of absorptive capacity typology for an innovation efficiency process. The influence of the potential and realized absorptive capacity on new products is significant and causes effects on internal research and development in diverse way. The impact of the joint ventures, suppliers’ cooperation and customers’ cooperation are significant on absorptive capacity. Research limitations/implications: It would be interesting to extend the research to another innovation metrics as new organizational methods, new processes, new designs or new methods in the use of sales channels. Practical implications: The agreement of cooperation activities constitutes an important decision for the firm’s innovation. Companies must be conscious that while suppliers and customers’ cooperation are relevant cooperation actions to increase the internal research and development, joint ventures and customers’ cooperation are significant to the growth of the new products. Social implications: The types of absorptive capacity and internal research and development serve as mediating mechanisms between cooperative activities and innovative performance. Originality/value: This paper advances the literature on absorptive capacity by showing how firms use their positions of technological vigilance and management to form their capabilities, and subsequently, to enhance innovation outcomes. This study considers it is necessary to analyze the typology of the absorptive capacity that can allow managers to understand an innovation efficiency

Alternative vision or utopian fantasy? Cooperation, empowerment and women's cooperative development in India.

Science.gov (United States)

Mayoux, L

1995-01-01

The discussion addresses the costs and benefits of working in cooperatives in India, imposed participation, methods for increasing incomes, preconceived models, the importance of meeting the actual needs of women, and participatory options. This author evaluated 10 producer cooperatives in West Bengal, Karnataka, and Tamil Nadu during 1984-92. It is argued that more discussion is needed on how ideals of cooperation and empowerment of women can occur simultaneous with the context in which cooperatives must operate. The ten study cooperatives were all officially registered cooperatives. Cooperatives varied in size, organizational structure, and forms of support. Four were determined to be successful in economic and participatory terms. Three were successful because of the efforts of the women themselves. All three cases were based on earning goals that were higher than the women could have achieved on their own. Six failed in terms of participatory decision making and cooperative operations. Lack of sufficient support and/or excessive bureaucratic red tape were involved in the six failures, but to varying degrees. Type of support and means of implementation were important in the six failures. All women used cooperatives as a means of increasing income. Participation rules were imposed by outside agencies. Women were given "cooperative" training. Disputes occurred because women selected to power positions were powerful leaders outside the cooperative. Consensus was difficult to reach. There were conflicts of interest between different departments. Quality control was made difficult by women's inability to provide discipline. Personal conflicts from outside were carried on within the cooperative. Incomes could be improved by training women in local marketing and networking, insuring adequate resources and capital, and providing savings schemes. Gender inequalities were a key factor limiting income for women, but cooperatives did not address this issue. Gains for women

Grouped to Achieve: Are There Benefits to Assigning Students to Heterogeneous Cooperative Learning Groups Based on Pre-Test Scores?

Science.gov (United States)

Werth, Arman Karl

Cooperative learning has been one of the most widely used instructional practices around the world since the early 1980's. Small learning groups have been in existence since the beginning of the human race. These groups have grown in their variance and complexity overtime. Classrooms are getting more diverse every year and instructors need a way to take advantage of this diversity to improve learning. The purpose of this study was to see if heterogeneous cooperative learning groups based on student achievement can be used as a differentiated instructional strategy to increase students' ability to demonstrate knowledge of science concepts and ability to do engineering design. This study includes two different groups made up of two different middle school science classrooms of 25-30 students. These students were given an engineering design problem to solve within cooperative learning groups. One class was put into heterogeneous cooperative learning groups based on student's pre-test scores. The other class was grouped based on random assignment. The study measured the difference between each class's pre-post gains, student's responses to a group interaction form and interview questions addressing their perceptions of the makeup of their groups. The findings of the study were that there was no significant difference between learning gains for the treatment and comparison groups. There was a significant difference between the treatment and comparison groups in student perceptions of their group's ability to stay on task and manage their time efficiently. Both the comparison and treatment groups had a positive perception of the composition of their cooperative learning groups.

Vacua of maximal gauged D=3 supergravities

International Nuclear Information System (INIS)

Fischbacher, T; Nicolai, H; Samtleben, H

2002-01-01

We analyse the scalar potentials of maximal gauged three-dimensional supergravities which reveal a surprisingly rich structure. In contrast to maximal supergravities in dimensions D≥4, all these theories possess a maximally supersymmetric (N=16) ground state with negative cosmological constant Λ 2 gauged theory, whose maximally supersymmetric groundstate has Λ = 0. We compute the mass spectra of bosonic and fermionic fluctuations around these vacua and identify the unitary irreducible representations of the relevant background (super)isometry groups to which they belong. In addition, we find several stationary points which are not maximally supersymmetric, and determine their complete mass spectra as well. In particular, we show that there are analogues of all stationary points found in higher dimensions, among them are de Sitter (dS) vacua in the theories with noncompact gauge groups SO(5, 3) 2 and SO(4, 4) 2 , as well as anti-de Sitter (AdS) vacua in the compact gauged theory preserving 1/4 and 1/8 of the supersymmetries. All the dS vacua have tachyonic instabilities, whereas there do exist nonsupersymmetric AdS vacua which are stable, again in contrast to the D≥4 theories

[Cooperation, Job Satisfaction and Burn Out - Sustainability in Outpatient Mental Health Care among Medical Specialists in Germany].

Science.gov (United States)

Baumgardt, Johanna; Moock, Jörn; Rössler, Wulf; Kawohl, Wolfram

2017-04-01

Objective Cooperation, job satisfaction, and burn out risk are indicators of sustainability in mental health services. Thus they were assessed among registered medical specialists in outpatient mental health care in Germany. Method A postal survey consisting of three questionnaires about cooperation, job satisfaction, and burnout was carried out among all registered medical specialists in outpatient mental health care in Germany (n = 4,430). Results 14.1 % (n = 626) of the specialists responded to the survey. Quality and quantity of cooperation regarding mental health care services were rated diverse, job satisfaction was assessed medium to high, and burnout risk was low to medium. Higher job satisfaction correlated with good quality of cooperation, fewer years of practice, fewer patients' chronically ill, more patients who as well seek psychotherapy, and less time spent on cooperation. Low burn out risk correlated with good quality of cooperation, higher age, single practice setting and a higher amount of patients who as well seek psychotherapy. Conclusion Quality and quantity of cooperation in outpatient mental health care - especially regarding community mental health care institutions - should be fostered. Aspects to be considered to reinforce job satisfaction and minimize burn out risk are age, years of practice, quality and quantity of cooperation, practice setting, and the mixture of patients. © Georg Thieme Verlag KG Stuttgart · New York.

Monogamy and high relatedness do not preferentially favor the evolution of cooperation

Directory of Open Access Journals (Sweden)

Nonacs Peter

2011-03-01

Full Text Available Abstract Background Phylogenetic analyses strongly associate nonsocial ancestors of cooperatively-breeding or eusocial species with monogamy. Because monogamy creates high-relatedness family groups, kin selection has been concluded to drive the evolution of cooperative breeding (i.e., the monogamy hypothesis. Although kin selection is criticized as inappropriate for modeling and predicting the evolution of cooperation, there are no examples where specific inclusive fitness-based predictions are intrinsically wrong. The monogamy hypothesis may be the first case of such a flawed calculation. Results A simulation model mutated helping alleles into non-cooperative populations where females mated either once or multiply. Although multiple mating produces sibling broods of lower relatedness, it also increases the likelihood that one offspring will adopt a helper role. Examining this tradeoff showed that under a wide range of conditions polygamy, rather than monogamy, allowed helping to spread more rapidly through populations. Further simulations with mating strategies as heritable traits confirmed that multiple-mating is selectively advantageous. Although cooperation evolves similarly regardless of whether dependent young are close or more distant kin, it does not evolve if they are unrelated. Conclusions The solitary ancestral species to cooperative breeders may have been predominantly monogamous, but it cannot be concluded that monogamy is a predisposing state for the evolution of helping behavior. Monogamy may simply be coincidental to other more important life history characteristics such as nest defense or sequential provisioning of offspring. The differing predictive outcome from a gene-based model also supports arguments that inclusive fitness formulations poorly model some evolutionary questions. Nevertheless, cooperation only evolves when benefits are provided for kin: helping alleles did not increase in frequency in the absence of potential

Teleworking through cooperation

Directory of Open Access Journals (Sweden)

Dario Minervini

2006-07-01

Full Text Available La diffusion des TIC a des effets majeurs sur la société et sur l’économie. L’effet des nouvelles technologies sur le travail est évident dans les transformations de l’organisation du travail et des pratiques dans les organisations. Le télétravail est un bon exemple de ces nouvelles pratiques. Le présent texte expose les résultats d’un projet de recherche récemment mené sur le télétravail. Contrairement à l’approche qui présente un modèle d’avantages pour les acteurs économiques et sociaux, notre hypothèse est que le schème dialogique est lié aux nouvelles technologies et que la coopération est une dimension importante du télétravail. Dans notre étude, la coopération est observée à la fois dans les relations sociales entre employeurs et employés, et dans l’institutionnalisation de relations entre managers et syndicats. Bien que les deux formes de coopération, appelées ici coopération sociale et coopération institutionnelle, soient souvent considérées comme des prérequis aux « meilleures pratiques » en matière de nouvelles organisations du travail, nos études de cas montrent que la coopération n’est pas toujours au rendez-vous, ce qui rend difficile la mise en place des pratiques de télétravail. Nous discutons des résultats de diverses études de cas dans l’industrie et les services en nous centrant sur les relations de coopération et ce, afin de contribuer au débat sociologique sur le télétravail.The diffusion of ICT has massive effects on society and economy. The impact of the new technologies on work is apparent in new ways of organizing work and in new practices introduced in organizations. Telework is one good example within these. In this paper, we present the results of a recent research project on telework, in which we have been engaged. Differently from the approach referring to a model of benefits for economic and social actors, our hypothesis is that the dialogical

Sex differences in autonomic function following maximal exercise.

Science.gov (United States)

Kappus, Rebecca M; Ranadive, Sushant M; Yan, Huimin; Lane-Cordova, Abbi D; Cook, Marc D; Sun, Peng; Harvey, I Shevon; Wilund, Kenneth R; Woods, Jeffrey A; Fernhall, Bo

2015-01-01

Heart rate variability (HRV), blood pressure variability, (BPV) and heart rate recovery (HRR) are measures that provide insight regarding autonomic function. Maximal exercise can affect autonomic function, and it is unknown if there are sex differences in autonomic recovery following exercise. Therefore, the purpose of this study was to determine sex differences in several measures of autonomic function and the response following maximal exercise. Seventy-one (31 males and 40 females) healthy, nonsmoking, sedentary normotensive subjects between the ages of 18 and 35 underwent measurements of HRV and BPV at rest and following a maximal exercise bout. HRR was measured at minute one and two following maximal exercise. Males have significantly greater HRR following maximal exercise at both minute one and two; however, the significance between sexes was eliminated when controlling for VO2 peak. Males had significantly higher resting BPV-low-frequency (LF) values compared to females and did not significantly change following exercise, whereas females had significantly increased BPV-LF values following acute maximal exercise. Although males and females exhibited a significant decrease in both HRV-LF and HRV-high frequency (HF) with exercise, females had significantly higher HRV-HF values following exercise. Males had a significantly higher HRV-LF/HF ratio at rest; however, both males and females significantly increased their HRV-LF/HF ratio following exercise. Pre-menopausal females exhibit a cardioprotective autonomic profile compared to age-matched males due to lower resting sympathetic activity and faster vagal reactivation following maximal exercise. Acute maximal exercise is a sufficient autonomic stressor to demonstrate sex differences in the critical post-exercise recovery period.

Restoring lepidopteran diversity in a tropical dry forest: relative importance of restoration treatment, tree identity and predator pressure

Directory of Open Access Journals (Sweden)

Lizet Solis-Gabriel

2017-05-01

Full Text Available Tropical dry forests (TDFs have been widely transformed by human activities worldwide and the ecosystem services they provide are diminishing. There has been an urgent call for conservation and restoration of the degraded lands previously occupied by TDFs. Restoration experiences aim to recover species diversity and ecological functions. Different restoration strategies have been used to maximize plant performance including weeding, planting or using artificial mulching. In this investigation, we evaluated whether different restoration practices influence animal arrival and the reestablishment of biotic interactions. We particularly evaluated lepidopteran larvae diversity and caterpillar predation on plants established under different restoration treatments (mulching, weeding and control in the Pacific West Coast of México. This study corroborated the importance of plant host identity for lepidopteran presence in a particular area. Lepidopteran diversity and herbivory rates were not affected by the restoration treatment but they were related to tree species. In contrast, caterpillar predation marks were affected by restoration treatment, with a greater number of predation marks in control plots, while caterpillar predation marks among plant species were not significantly different. This study highlights the importance of considering the introduction of high plant species diversity when planning TDF restoration to maximize lepidopteran diversity and ecosystem functioning.

Restoring lepidopteran diversity in a tropical dry forest: relative importance of restoration treatment, tree identity and predator pressure.

Science.gov (United States)

Solis-Gabriel, Lizet; Mendoza-Arroyo, Wendy; Boege, Karina; Del-Val, Ek

2017-01-01

Tropical dry forests (TDFs) have been widely transformed by human activities worldwide and the ecosystem services they provide are diminishing. There has been an urgent call for conservation and restoration of the degraded lands previously occupied by TDFs. Restoration experiences aim to recover species diversity and ecological functions. Different restoration strategies have been used to maximize plant performance including weeding, planting or using artificial mulching. In this investigation, we evaluated whether different restoration practices influence animal arrival and the reestablishment of biotic interactions. We particularly evaluated lepidopteran larvae diversity and caterpillar predation on plants established under different restoration treatments (mulching, weeding and control) in the Pacific West Coast of México. This study corroborated the importance of plant host identity for lepidopteran presence in a particular area. Lepidopteran diversity and herbivory rates were not affected by the restoration treatment but they were related to tree species. In contrast, caterpillar predation marks were affected by restoration treatment, with a greater number of predation marks in control plots, while caterpillar predation marks among plant species were not significantly different. This study highlights the importance of considering the introduction of high plant species diversity when planning TDF restoration to maximize lepidopteran diversity and ecosystem functioning.

Eccentric exercise decreases maximal insulin action in humans

DEFF Research Database (Denmark)

Asp, Svend; Daugaard, J R; Kristiansen, S

1996-01-01

subjects participated in two euglycaemic clamps, performed in random order. One clamp was preceded 2 days earlier by one-legged eccentric exercise (post-eccentric exercise clamp (PEC)) and one was without the prior exercise (control clamp (CC)). 2. During PEC the maximal insulin-stimulated glucose uptake...... for all three clamp steps used (P maximal activity of glycogen synthase was identical in the two thighs for all clamp steps. 3. The glucose infusion rate (GIR......) necessary to maintain euglycaemia during maximal insulin stimulation was lower during PEC compared with CC (15.7%, 81.3 +/- 3.2 vs. 96.4 +/- 8.8 mumol kg-1 min-1, P maximal...

Parameter Diversity Induced Multiple Spatial Coherence Resonances and Spiral Waves in Neuronal Network with and Without Noise

International Nuclear Information System (INIS)

Li Yuye; Jia Bing; Gu Huaguang; An Shucheng

2012-01-01

Diversity in the neurons and noise are inevitable in the real neuronal network. In this paper, parameter diversity induced spiral waves and multiple spatial coherence resonances in a two-dimensional neuronal network without or with noise are simulated. The relationship between the multiple resonances and the multiple transitions between patterns of spiral waves are identified. The coherence degrees induced by the diversity are suppressed when noise is introduced and noise density is increased. The results suggest that natural nervous system might profit from both parameter diversity and noise, provided a possible approach to control formation and transition of spiral wave by the cooperation between the diversity and noise. (general)

Differential Experiences of Women and Minority Engineering Students in a Cooperative Education Program

Science.gov (United States)

Fifolt, Matthew M.; Abbott, Gypsy

Although slight gains have been made in attracting women and minority students to the field of engineering, the differences are not great enough to meet current economic demands [National Academy of Sciences (2007). Rising above the gathering storm: Energizing and employing America for a brighter economic future, Washington, DC: National Academies Press]. Therefore, it has become imperative that colleges and universities increase efforts to both recruit and retain these students who express interest in the STEM fields [National Science Foundation (2006), Women, minorities, and persons with disabilities in science and engineering, NSF 4-311, Arlington, VA: NSF]. In engineering, one promising venue for students to gain professional experience as part of their undergraduate training is through cooperative education (co-op). However, there is a dearth of information in the research literature regarding how co-op programs can be structured to address the needs of diverse students. There is consensus, however, about one aspect of addressing the needs of diverse students, namely, mentoring and role models are key strategies for success. In this study, a mixed methods design was used to examine students' perceptions of mentoring in a cooperative education program in a southeastern university. Using Noe's [Noe, R. (1988). An investigation of the determinants of successful assigned mentoring relationships. Personnel Psychology, 1, 457-479] mentoring functions scales, which described psychosocial and career-related support, research findings indicated a statistically significant difference between gender and the psychosocial aspect of mentoring. Analysis of the qualitative data further confirmed differences in cooperative education experiences with respect to both gender and ethnicity.

Maximize x(a - x)

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Lange, L. H.

1974-01-01

Five different methods for determining the maximizing condition for x(a - x) are presented. Included is the ancient Greek version and a method attributed to Fermat. None of the proofs use calculus. (LS)

International co-operation

International Nuclear Information System (INIS)

Klinda, J.; Lieskovska, Z.

1998-01-01

Within the Union Nations (UN) framework, the Slovak Republic participated in following activities on environment protection co-operation: UN European Economic Commission, UN Industrial Development Organization, UN Development Programme, UN Human Habitat Organization, UN Environment Programme, and UN Commission on Sustainable Development. Relevant activities of the Slovak Republic in these co-operations as well as in European Union and OECD activities are reviewed. International conventions and other forms of multilateral co-operation, bilateral co-operation, and international programmes and projects in which the Slovak Republic took participate are presented

Effect of heterogeneous investments on the evolution of cooperation in spatial public goods game.

Science.gov (United States)

Huang, Keke; Wang, Tao; Cheng, Yuan; Zheng, Xiaoping

2015-01-01

Understanding the emergence of cooperation in spatial public goods game remains a grand challenge across disciplines. In most previous studies, it is assumed that the investments of all the cooperators are identical, and often equal to 1. However, it is worth mentioning that players are diverse and heterogeneous when choosing actions in the rapidly developing modern society and researchers have shown more interest to the heterogeneity of players recently. For modeling the heterogeneous players without loss of generality, it is assumed in this work that the investment of a cooperator is a random variable with uniform distribution, the mean value of which is equal to 1. The results of extensive numerical simulations convincingly indicate that heterogeneous investments can promote cooperation. Specifically, a large value of the variance of the random variable can decrease the two critical values for the result of behavioral evolution effectively. Moreover, the larger the variance is, the better the promotion effect will be. In addition, this article has discussed the impact of heterogeneous investments when the coevolution of both strategy and investment is taken into account. Comparing the promotion effect of coevolution of strategy and investment with that of strategy imitation only, we can conclude that the coevolution of strategy and investment decreases the asymptotic fraction of cooperators by weakening the heterogeneity of investments, which further demonstrates that heterogeneous investments can promote cooperation in spatial public goods game.

A novel ergodic capacity analysis of diversity combining and multihop transmission systems over generalized composite fading channels

KAUST Repository

Yilmaz, Ferkan

2012-06-01

Ergodic capacity is an important performance measure associated with reliable communication at the highest rate at which information can be sent over the channel with a negligible probability of error. In the shadow of this definition, diversity receivers (such as selection combining, equal-gain combining and maximal-ratio combining) and transmission techniques (such as cascaded fading channels, amplify-and-forward multihop transmission) are deployed in mitigating various performance impairing effects such as fading and shadowing in digital radio communication links. However, the exact analysis of ergodic capacity is in general not always possible for all of these forms of diversity receivers and transmission techniques over generalized composite fading environments due to it\\'s mathematical intractability. In the literature, published papers concerning the exact analysis of ergodic capacity have been therefore scarce (i.e., only [1] and [2]) when compared to those concerning the exact analysis of average symbol error probability. In addition, they are essentially targeting to the ergodic capacity of the maximal ratio combining diversity receivers and are not readily applicable to the capacity analysis of the other diversity combiners / transmission techniques. In this paper, we propose a novel moment generating function-based approach for the exact ergodic capacity analysis of both diversity receivers and transmission techniques over generalized composite fading environments. As such, we demonstrate how to simultaneously treat the ergodic capacity analysis of all forms of both diversity receivers and multihop transmission techniques. © 2012 IEEE.

Cooperatives between truth and validity

Directory of Open Access Journals (Sweden)

Guilherme Krueger

2014-12-01

Full Text Available The current declaration of the International Cooperative Alliance on cooperative identity since its 1995 Centennial Conference (which was held in Manchester makes no distinction between cooperation and cooperative. The lack of distinction between cooperation and cooperative has caused the Decennial Cooperative Action Plan to define cooperatives as a form, while their materiality is regarded as managerial: a business (activity under a cooperative form. An identity that is close to us cannot be reduced to form, without this being a problem. Therefore, the value underlying this identity —cooperation— must have a substantial basis, even if it is idealised, if it is to affect us.Received: 27.03.2014Accepted: 12.05.2014

Aspects of Sustainability: Cooperation, Job Satisfaction, and Burnout among Swiss Psychiatrists.

Science.gov (United States)

Baumgardt, Johanna; Moock, Jörn; Rössler, Wulf; Kawohl, Wolfram

2015-01-01

Greater sustainability in mental health services is frequently demanded but seldom analyzed. Levels of cooperation, job satisfaction, and burnout are indicators of social sustainability in this field and are of particular importance to medical staff. Because registered psychiatrists play a central role, we assessed the status quo and interactions between these three factors among registered psychiatrists in Switzerland. A postal survey with three standardized questionnaires about cooperation, job satisfaction, and burnout was conducted among all registered psychiatrists in the German-speaking part of Switzerland (n = 1485). Addresses were provided by the Swiss Medical Association. Response rate was 23.7% (n = 352), yielding a largely male sample (62.8%; n = 218) aged 55.5 ± 8.7 years old. Quantity (47 ± 56.2 contacts over 3 months) and duration (91.1 ± 101.6 min per week) of cooperation was found to be diverse depending on the stakeholder. Quality of cooperation was greatest in general practitioners (81.5%) while it was worst in community mental health providers (54.9%). Overall job satisfaction was assessed rather high (3.7 ± 0.8), and burnout rates were below crucial values (Emotional Exhaustion, 2.9 ± 0.8; Depersonalization, 1.9 ± 0.5). Both were positively influenced by cooperation. The strongest correlation was found between job satisfaction and burnout, and both had significant inverse relationships in all dimensions. To foster sustainability in outpatient mental health care regarding cooperation, job satisfaction, and burnout, personal aspects such and age or years of registration, organizational aspects, such as networking and practice setting, as wells as supportive aspects such as psychotherapy, and self-help groups, must be considered. Quality of cooperation should be reinforced in particular. Because Integrated and Managed Care models cover several of these factors, the models should be more strongly

Conflictual cooperation

DEFF Research Database (Denmark)

Axel, Erik

2011-01-01

, cooperation appeared as the continuous reworking of contradictions in the local arrangement of societal con- ditions. Subjects were distributed and distributed themselves according to social privileges, resources, and dilemmas in cooperation. Here, the subjects’ activities and understandings took form from...

Cooperative Monitoring Center Occasional Paper/12: ENTNEA: A Concept for Enhancing Nuclear Transparency for Confidence Building in Northeast Asia

International Nuclear Information System (INIS)

Nam, Man-Kwon; Shin, Sung-Tack

1999-01-01

Nuclear energy continues to be a strong and growing component of economic development in Northeast Asia. A broad range of nuclear energy systems already exists across the region and vigorous growth is projected. Associated with these capabilities and plans are various concerns about operational safety, environmental protection, and accumulation of spent fuel and other nuclear materials. We consider cooperative measures that might address these concerns. The confidence building measures suggested here center on the sharing of information to lessen concerns about nuclear activities or to solve technical problems. These activities are encompassed by an Enhanced Nuclear Transparency in Northeast Asia (ENTNEA) concept that would be composed of near-term, information-sharing activities and an eventual regional institution. The near-term activities would address specific concerns and build a tradition of cooperation; examples include radiation measurements for public safety and emergency response, demonstration of safe operations at facilities and in transportation, and material security in the back end of the fuel cycle. Linkages to existing efforts and organizations would be sought to maximize the benefits of cooperation. In the longer term, the new cooperative tradition might evolve into an ENTNEA institution. In institutional form, ENTNEA could combine the near-term activities and new cooperative activities, which might require an institutional basis, for the mutual benefit and security of regional parties

Pillars of peace: The evolution of nuclear technical cooperation

International Nuclear Information System (INIS)

Cetto, A.M.

2003-01-01

The twentieth century witnessed unprecedented scientific and technological progress, unfortunately paralleled by the development of weapons of mass destruction. And with this progress came an incredible amount of responsibility for scientists and governments. The creation of the IAEA and its technical cooperation programme brought together scientists and governments to use nuclear technology for the 'peaceful pursuits of mankind'. The programme supports application of nuclear techniques to solve socio-economic and human development problems in areas as diverse as agriculture, health, natural resource management, and radiation protection. Fifty years after President Eisenhower's famous 'Atoms for Peace' speech, the IAEA technical cooperation programme provides more than $70 million worth of experts, training, and procurement services each year to approximately 75% of its 137 Member States. But as development budgets shrink, the programme is seeking to make more meaningful use of resources at hand (national capacities, regional resources, development partners and the voluntary Technical Cooperation Fund), targeting specific problems of Member States and partnering with other sustainable development organizations. At the same time, efforts continue to overcome the past legacy that necessitated the 'Atoms for Peace' proposal in the first place. Even as development challenges are addressed, the IAEA, its partners and governments face other challenges along the way, including public opinion for a technology that had a devastating global introduction

Diversity in research projects - A key to success?

Science.gov (United States)

Henkel, Daniela; Eisenhauer, Anton; Taubner, Isabelle

2017-04-01

According to demographers, psychologists, sociologists and economists diverse groups, which are groups of different race, ethnicity, gender and sexual orientation, are more innovative than homogeneous groups. This is also true for groups working together in research collaborations and international cooperation involving a culturally and functionally diverse mix of individuals who have to be integrated into an effective unit - a project team. If the goal is scientific excellence, diversity should be an essential ingredient to conduct science on high level productivity, quality and innovation. Effective teamwork is a key to project success and prime responsibilities of the project manager. Therefore, the project manager has to take into consideration different characteristics such as cultures, languages, and different values related to individual project partners. Here we show how diversity can affect the performance of a research project. Furthermore, the presentation indicates skills and abilities which are required for the management in order to deal also with the challenges of diversity in research projects. The presentation is based on insights experienced in the context of an Innovative Training Network (ITN) project within Marie Skłodowska-Curie Actions of the European HORIZON 2020 program and TRION a Collaborative Research Project in the Framework of the Trilateral Program of the German Research Foundation.

COOPERATION BETWEEN INSTITUTIONS OF PUBLIC ORDER AND SAFETY FROM BIHOR (ROMANIA AND HAJDU-BIHAR (HUNGARY: A CASE STUDY

Directory of Open Access Journals (Sweden)

Bucur Catalin-Adrian

2012-07-01

Full Text Available The forms and degree of cooperation between public order and safety on both sides of the border took on different forms from country to country, from one region to another. Some countries have a very extensive inter-institutional cooperation and substantial, while in other countries relations are characterized by a deep division, competition and lack of communication. To understand existing forms of cooperation, and how best practices can be transferred to some Member States it is necessary to understand the existing diversity across the European Union. This paper focuses on presenting several cooperation projects with direct reference to public order and safety activities implemented in Bihor - Hajdu-Bihar euroregion, within the CBC Programme Hungary-Romania 2004 and especially the project "Mirror network for operative and operational data trasfer", a joint project of cooperation in the public order and safety in Bihor - Hajdu-Bihar Euroregion. This paper is part of the doctoral thesis on Integrate perspective on companies sector, coordinated by professor Ph.D. Alina Bn#259;dulescu from University of Oradea, Faculty of Economics.

Utility Maximization in Nonconvex Wireless Systems

CERN Document Server

Brehmer, Johannes

2012-01-01

This monograph formulates a framework for modeling and solving utility maximization problems in nonconvex wireless systems. First, a model for utility optimization in wireless systems is defined. The model is general enough to encompass a wide array of system configurations and performance objectives. Based on the general model, a set of methods for solving utility maximization problems is developed. The development is based on a careful examination of the properties that are required for the application of each method. The focus is on problems whose initial formulation does not allow for a solution by standard convex methods. Solution approaches that take into account the nonconvexities inherent to wireless systems are discussed in detail. The monograph concludes with two case studies that demonstrate the application of the proposed framework to utility maximization in multi-antenna broadcast channels.

Fairness-Aware Energy-Efficient Resource Allocation for AF Co-Operative OFDMA Networks

KAUST Repository

Bedeer, Ebrahim

2015-09-23

In this paper, we adopt an energy-efficiency (EE) metric, named worst-EE, that is suitable for EE fairness optimization in the uplink transmission of amplify-and-forward (AF) cooperative orthogonal frequency division multiple access (OFDMA) networks. More specifically, we assign subcarriers and allocate powers for mobile and relay stations in order to maximize the worst-EE, i.e., to maximize the EE of the mobile station (MS) with the lowest EE value, subject to MSs transmit power, relay station (RS) transmit power, and MSs quality-of-service (QoS) constraints. The formulated primal max-min optimization problem is nonconvex fractional mixed integer nonlinear program, i.e., NP-hard to solve. We provide a novel optimization framework that studies the structure of the primal problem and prove that the dual min-max optimization problem attains the same optimal solution of the primal problem. Additionally, we propose a modified Dinkelbach algorithm, named dual Dinkelbach, to achieve the optimal solution of the dual problem in a polynomial time complexity. We further exploit the structure of the obtained optimal solution and develop a low complexity suboptimal heuristic. Numerical results show the effectiveness of the proposed algorithm to improve the network performance in terms of fairness between MSs, worst-EE, and average network transmission rate when compared to traditional schemes that maximize the EE of the whole network. Presented results also show that the suboptimal heuristic balances the achieved performance and the computational complexity.

Fairness-Aware Energy-Efficient Resource Allocation for AF Co-Operative OFDMA Networks

KAUST Repository

Bedeer, Ebrahim; Alorainy, Abdulaziz; Hossain, Md. Jahangir; Amin, Osama; Alouini, Mohamed-Slim

2015-01-01

In this paper, we adopt an energy-efficiency (EE) metric, named worst-EE, that is suitable for EE fairness optimization in the uplink transmission of amplify-and-forward (AF) cooperative orthogonal frequency division multiple access (OFDMA) networks. More specifically, we assign subcarriers and allocate powers for mobile and relay stations in order to maximize the worst-EE, i.e., to maximize the EE of the mobile station (MS) with the lowest EE value, subject to MSs transmit power, relay station (RS) transmit power, and MSs quality-of-service (QoS) constraints. The formulated primal max-min optimization problem is nonconvex fractional mixed integer nonlinear program, i.e., NP-hard to solve. We provide a novel optimization framework that studies the structure of the primal problem and prove that the dual min-max optimization problem attains the same optimal solution of the primal problem. Additionally, we propose a modified Dinkelbach algorithm, named dual Dinkelbach, to achieve the optimal solution of the dual problem in a polynomial time complexity. We further exploit the structure of the obtained optimal solution and develop a low complexity suboptimal heuristic. Numerical results show the effectiveness of the proposed algorithm to improve the network performance in terms of fairness between MSs, worst-EE, and average network transmission rate when compared to traditional schemes that maximize the EE of the whole network. Presented results also show that the suboptimal heuristic balances the achieved performance and the computational complexity.

When cooperation begets cooperation: the role of key individuals in galvanizing support.

Science.gov (United States)

McAuliffe, Katherine; Wrangham, Richard; Glowacki, Luke; Russell, Andrew F

2015-12-05

Life abounds with examples of conspecifics actively cooperating to a common end, despite conflicts of interest being expected concerning how much each individual should contribute. Mathematical models typically find that such conflict can be resolved by partial-response strategies, leading investors to contribute relatively equitably. Using a case study approach, we show that such model expectations can be contradicted in at least four disparate contexts: (i) bi-parental care; (ii) cooperative breeding; (iii) cooperative hunting; and (iv) human cooperation. We highlight that: (a) marked variation in contributions is commonplace; and (b) individuals can often respond positively rather than negatively to the contributions of others. Existing models have surprisingly limited power in explaining these phenomena. Here, we propose that, although among-individual variation in cooperative contributions will be influenced by differential costs and benefits, there is likely to be a strong genetic or epigenetic component. We then suggest that selection can maintain high investors (key individuals) when their contributions promote support by increasing the benefits and/or reducing the costs for others. Our intentions are to raise awareness in--and provide testable hypotheses of--two of the most poorly understood, yet integral, questions regarding cooperative ventures: why do individuals vary in their contributions and when does cooperation beget cooperation? © 2015 The Author(s).

Parity-Check Network Coding for Multiple Access Relay Channel in Wireless Sensor Cooperative Communications

Directory of Open Access Journals (Sweden)

Du Bing

2010-01-01

Full Text Available A recently developed theory suggests that network coding is a generalization of source coding and channel coding and thus yields a significant performance improvement in terms of throughput and spatial diversity. This paper proposes a cooperative design of a parity-check network coding scheme in the context of a two-source multiple access relay channel (MARC model, a common compact model in hierarchical wireless sensor networks (WSNs. The scheme uses Low-Density Parity-Check (LDPC as the surrogate to build up a layered structure which encapsulates the multiple constituent LDPC codes in the source and relay nodes. Specifically, the relay node decodes the messages from two sources, which are used to generate extra parity-check bits by a random network coding procedure to fill up the rate gap between Source-Relay and Source-Destination transmissions. Then, we derived the key algebraic relationships among multidimensional LDPC constituent codes as one of the constraints for code profile optimization. These extra check bits are sent to the destination to realize a cooperative diversity as well as to approach MARC decode-and-forward (DF capacity.

An fMRI study of joint action – varying levels of cooperation correlates with activity in sensorimotor control, but not mentalization, networks

Directory of Open Access Journals (Sweden)

Thierry eChaminade

2012-06-01

Full Text Available As social agents, humans continuously interact with with the people around them. Here, motor cooperation was investigated by designing a situation in which pairs of participants, one being scanned with fMRI, controlled jointly a visually presented object with joystick movements. The object oscillated dynamically along two dimensions, shades of pink and width of gratings, corresponding to the two cardinal directions of joystick movements. While the overall control of each participant on the object was kept constant, the amount of cooperation along the two dimensions varied along four levels, from no (each participant controlled exclusively one dimension to full (each participant controlled half of each dimension cooperation. Increasing cooperation correlated with BOLD signal in the left parietal operculum and anterior cingulate cortex, while decreasing cooperation correlated with activity in the right inferior frontal and superior temporal gyri, in the intraparietal sulci and inferior temporal gyrii bilaterally, and in the dorsomedial prefrontal cortex. As joint control improved with the level of cooperation, we assessed the brain responses correlating with joint performance, and found that activity in most of the areas associated with levels of cooperation also correlated with the joint performance. The only brain area found exclusively in the negative correlation with cooperation was within the posterior region of the rostral medial frontal cortex, involved in the monitoring of action outcome. We therefore propose that this region responds to the predictability of visual feedback given the motor commands, which is maximal when participants do not cooperate as they fully control one dimension. Our results therefore indicate that, in the current experimental paradigm, the level of cooperation affects sensorimotor processing, but not mentalizing. Altogether, humans do not need to have access to others’ intentional states to cooperate on a joint

Effect of playing violent video games cooperatively or competitively on subsequent cooperative behavior.

Science.gov (United States)

Ewoldsen, David R; Eno, Cassie A; Okdie, Bradley M; Velez, John A; Guadagno, Rosanna E; DeCoster, Jamie

2012-05-01

Research on video games has yielded consistent findings that violent video games increase aggression and decrease prosocial behavior. However, these studies typically examined single-player games. Of interest is the effect of cooperative play in a violent video game on subsequent cooperative or competitive behavior. Participants played Halo II (a first-person shooter game) cooperatively or competitively and then completed a modified prisoner's dilemma task to assess competitive and cooperative behavior. Compared with the competitive play conditions, players in the cooperative condition engaged in more tit-for-tat behaviors-a pattern of behavior that typically precedes cooperative behavior. The social context of game play influenced subsequent behavior more than the content of the game that was played.

Aging and loss decision making: increased risk aversion and decreased use of maximizing information, with correlated rationality and value maximization.

Science.gov (United States)

Kurnianingsih, Yoanna A; Sim, Sam K Y; Chee, Michael W L; Mullette-Gillman, O'Dhaniel A

2015-01-01

We investigated how adult aging specifically alters economic decision-making, focusing on examining alterations in uncertainty preferences (willingness to gamble) and choice strategies (what gamble information influences choices) within both the gains and losses domains. Within each domain, participants chose between certain monetary outcomes and gambles with uncertain outcomes. We examined preferences by quantifying how uncertainty modulates choice behavior as if altering the subjective valuation of gambles. We explored age-related preferences for two types of uncertainty, risk, and ambiguity. Additionally, we explored how aging may alter what information participants utilize to make their choices by comparing the relative utilization of maximizing and satisficing information types through a choice strategy metric. Maximizing information was the ratio of the expected value of the two options, while satisficing information was the probability of winning. We found age-related alterations of economic preferences within the losses domain, but no alterations within the gains domain. Older adults (OA; 61-80 years old) were significantly more uncertainty averse for both risky and ambiguous choices. OA also exhibited choice strategies with decreased use of maximizing information. Within OA, we found a significant correlation between risk preferences and choice strategy. This linkage between preferences and strategy appears to derive from a convergence to risk neutrality driven by greater use of the effortful maximizing strategy. As utility maximization and value maximization intersect at risk neutrality, this result suggests that OA are exhibiting a relationship between enhanced rationality and enhanced value maximization. While there was variability in economic decision-making measures within OA, these individual differences were unrelated to variability within examined measures of cognitive ability. Our results demonstrate that aging alters economic decision-making for

Aging and loss decision making: increased risk aversion and decreased use of maximizing information, with correlated rationality and value maximization

Directory of Open Access Journals (Sweden)

Yoanna Arlina Kurnianingsih

2015-05-01

Full Text Available We investigated how adult aging specifically alters economic decision-making, focusing on examining alterations in uncertainty preferences (willingness to gamble and choice strategies (what gamble information influences choices within both the gains and losses domains. Within each domain, participants chose between certain monetary outcomes and gambles with uncertain outcomes. We examined preferences by quantifying how uncertainty modulates choice behavior as if altering the subjective valuation of gambles. We explored age-related preferences for two types of uncertainty, risk and ambiguity. Additionally, we explored how aging may alter what information participants utilize to make their choices by comparing the relative utilization of maximizing and satisficing information types through a choice strategy metric. Maximizing information was the ratio of the expected value of the two options, while satisficing information was the probability of winning.We found age-related alterations of economic preferences within the losses domain, but no alterations within the gains domain. Older adults (OA; 61 to 80 years old were significantly more uncertainty averse for both risky and ambiguous choices. OA also exhibited choice strategies with decreased use of maximizing information. Within OA, we found a significant correlation between risk preferences and choice strategy. This linkage between preferences and strategy appears to derive from a convergence to risk neutrality driven by greater use of the effortful maximizing strategy. As utility maximization and value maximization intersect at risk neutrality, this result suggests that OA are exhibiting a relationship between enhanced rationality and enhanced value maximization. While there was variability in economic decision-making measures within OA, these individual differences were unrelated to variability within examined measures of cognitive ability. Our results demonstrate that aging alters economic

Performing Ecosystem Services at Mud Flats in Seocheon, Korea: Using Q Methodology for Cooperative Decision Making

Directory of Open Access Journals (Sweden)

Jae-Hyuck Lee

2017-05-01

Full Text Available The concept of ecosystem services, which are the direct and indirect benefits of nature to humans, has been established as a supporting tool to increase the efficiency in decision-making regarding environmental planning. However, preceding studies on decision-making in relation to ecosystem services have been limited to identifying differences in perception, whereas few studies have reported cooperative alternatives. Therefore, this study aimed to present a method for cooperative decision-making among ecosystem service stakeholders using Q methodology. The results showed three perspectives on ecosystem services of small mud flat areas: ecological function, ecotourism, and human activity. The perspectives on cultural services and regulating services were diverse, whereas those on supporting services were similar. Thus, supporting services were considered crucial for the cooperative assessment and management of small mud flat ecosystems as well as for the scientific evaluation of regulating services. Furthermore, this study identified practical implementation measures to increase production through land management, to manufacture related souvenirs, and to link them to ecotourism. Overall, our results demonstrated the ideal process of cooperative decision-making to improve ecosystem services.

Proto-cooperation

DEFF Research Database (Denmark)

Herbert-Read, James E; Romanczuk, Pawel; Krause, Stefan

2016-01-01

beneficial if the cost of attacking is high, and only then when waiting times are short. Our findings provide evidence that cooperative benefits can be realized through the facilitative effects of individuals' hunting actions without spatial coordination of attacks. Such 'proto-cooperation' may be the pre...

Cooperating to learn teaching to cooperate: adviser processes for program implement CA/AC

Directory of Open Access Journals (Sweden)

José Ramón LAGO

2011-11-01

Full Text Available The aim of this paper is present some results of advise strategy to introduce cooperative learning from the «Cooperating to Learn/ Learning to Cooperate» CL/LC Programme. The first part situates the research project and the research objective focused on how introduction of CL/LC program through a process of advice facilitates permanent improvements to the inclusion of students. In the second we analyzed the phases and tasks of an adviser process for the introduction of cooperative learning and three stages to build on cooperative learning in school: the introduction, generalization and consolidation. The third part is the central part. We describe five process of adviser to implement cooperative learning which we can observe different degrees and modalities of collaboration between teachers and counselors and between teachers. Is possible the first step of a network centers to work cooperatively.

Maximally Informative Observables and Categorical Perception

OpenAIRE

Tsiang, Elaine

2012-01-01

We formulate the problem of perception in the framework of information theory, and prove that categorical perception is equivalent to the existence of an observable that has the maximum possible information on the target of perception. We call such an observable maximally informative. Regardless whether categorical perception is real, maximally informative observables can form the basis of a theory of perception. We conclude with the implications of such a theory for the problem of speech per...

Sustainable rural development and cross-border cooperation

Directory of Open Access Journals (Sweden)

Stojanović Žaklina

2009-01-01

Full Text Available The concept of sustainable rural development comprises three aspects - social, economical and ecological. They are supposed to act in synergy, but, at the same time, these aspects are supposed to be competitive. Agriculture, as a traditional activity of rural economy, contributes to the sustainable development of rural areas only if there is an adequate resources management. If not, there will be a significant degradation of rural environment. These are the reasons why sustainable agriculture development is emphasized since it maximizes productivity and minimizes negative effects on nature and human resources. In this context, one should observe the connection between agriculture and tourism existing in the EU, where the application of sustainable agricultural development concept produces external effects connected to biodiversity protection and environment in rural areas. These become a good foundation for the development of rural and ecotourism. EU enlargement induced diversification of support programmes that EU gives to the candidate countries, as well as to those who are just entering the process of stabilization and association to the EU. Through cross-border cooperation projects, many goals can be accomplished, among which aspiration for promotion of sustainable economical and social development in border regions is one of the leading. Knowing that these regions are usually passive and underdeveloped, the projects of cross-border cooperation could induce development of those activities in local economy, which could bring better living conditions and economic prosperity on the one hand, and protection of environment on the other. Examples of this kind of projects in Serbia can usually be found in rural and ecotourism development.

Performance analysis of best relay selection scheme for amplify-and-forward cooperative networks in identical Nakagami-m channels

KAUST Repository

Hussain, Syed Imtiaz

2010-06-01

In cooperative communication networks, the use of multiple relays between the source and the destination was proposed to increase the diversity gain. Since the source and all the relays must transmit on orthogonal channels, multiple relay cooperation is considered inefficient in terms of channel resources and bandwidth utilization. To overcome this problem, the concept of best relay selection was recently proposed. In this paper, we analyze the performance of the best relay selection scheme for a cooperative network with multiple relays operating in amplify-and-forward (AF) mode over identical Nakagami-m channels using exact source-relay-destination signal to noise ratio (SNR) expression. We derive accurate closed form expressions for various system parameters including probability density function (pdf) of end-to-end SNR, average output SNR, average probability of bit error and average channel capacity. T he analytical results are verified through extensive simulations. It is shown that the best relay selection scheme performs better than the regular all relay cooperation.

Cooperative Trust Games

Science.gov (United States)

2013-01-01

the more widely recognized competitive (non-cooperative) game theory. Cooperative game theory focuses on what groups of self-interested agents can...provides immediate justification for using non-cooperative game theory as the basis for modeling the purely competitive agents. 2.4. Superadditive...the competitive and altruistic contributions of the subset team. Definition: Given a payoff function ( ) in a subset team game , the total marginal

Cooperative strategies European perspectives

CERN Document Server

Killing, J Peter

1997-01-01

Cooperative Strategies: European Perspectives is one of three geographically targeted volumes in which the contributors present the most current research on topics such as advances in theories of cooperative strategies, the formation of cooperative alliances, the dynamics of partner relationships, and the role of information and knowledge in cooperative alliances. Blending conceptual insights with empirical analyses, the contributors highlight commonalities and differences across national, cultural, and trade zones. The chapters in this volume are anchored in a wide set of theoretical approaches, conceptual frameworks, and models, illustrating how rich the area of cooperative strategies is for scholarly inquiry.

Maximally Entangled Multipartite States: A Brief Survey

International Nuclear Information System (INIS)

Enríquez, M; Wintrowicz, I; Życzkowski, K

2016-01-01

The problem of identifying maximally entangled quantum states of a composite quantum systems is analyzed. We review some states of multipartite systems distinguished with respect to certain measures of quantum entanglement. Numerical results obtained for 4-qubit pure states illustrate the fact that the notion of maximally entangled state depends on the measure used. (paper)

Corporate Social Responsibility and Profit Maximizing Behaviour

OpenAIRE

Becchetti, Leonardo; Giallonardo, Luisa; Tessitore, Maria Elisabetta

2005-01-01

We examine the behavior of a profit maximizing monopolist in a horizontal differentiation model in which consumers differ in their degree of social responsibility (SR) and consumers SR is dynamically influenced by habit persistence. The model outlines parametric conditions under which (consumer driven) corporate social responsibility is an optimal choice compatible with profit maximizing behavior.

COOPERATION BETWEEN TEACHERS WITH LIBRARIAN SERVICE OF IN HIKMAH TELADAN ELEMENTARY SCHOOL

Directory of Open Access Journals (Sweden)

Selly Setiani

2017-02-01

Full Text Available Abstrak. Perpustakaan merupakan bagian integral dilingkungan sekolah, oleh karena itu perlu adanya kerjasama dalam memaksimalkan potensi layanan perpustakaan sekolah. Penelitian ini dilakukan untuk menemukan jawaban dari rumusan kerjasama antara guru dengan pustakawan dalam layanan perpustakaan sekolah di Perpustakaan SD Hikmah Teladan. Selain dari itu untuk mengetahui bentuk kerjasama dalam layanan perpustakaan sekolah dan untuk mengetahui kriteria layanan perpustakaan sekolah. Penelitian ini menggunakan pendekatan kualitatif dengan metode deskriptif. Teknik yang digunakan untuk pengambilan sampel yaitu teknik purposive sampling. Teknik pengumpulan data dilakukan dengan cara wawancara, observasi dan studi dokumentasi. Teknik pengolahan data dilakukan dengan cara reduksi data, analisis data dan penarikan kesimpulan. Hasil penelitian menunjukan bahwa terdapat kerjasama antara guru dengan pustakawan dalam layanan perpustakaan sekolah. kerjasama penting untuk dilakukan guna mengoptimalkan potensi layanan perpustakaan sekolah. kerjasama yang dilakukan yaitu dalam bentuk pelaksanaan program kegiatan perpustakaan, pembinaan minat baca, promosi perpustakaan dan pembinaan koleksi. Perpustakaan SD Hikmah Teladan sebagai perpustakaan sekolah perlu melakukan kerjasama dengan berbagai pihak secara terus menerus dalam layanan perpustakaan sekolah. Kata kunci: kerjasama guru dengan pustakawan, layanan perpustakaan, pustakawan sekolah Abstract. The library is an integral part of the school environment, therefore the need for cooperation in maximizing the potential of school library services. This research is done to find the answer from the formula of cooperation between teachers and librarians in the school library services in elementary school libraries Hikmah Teladan. Aside from that to determine the form of cooperation in the school library services and to determine the criteria for school library services, theoretically and practically expected results of

Cooperatives management evaluation of four Savings and Credit Cooperatives of Quito, Ecuador

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Richard Joel Alba Caluguillin

2017-07-01

Full Text Available The administrative management in cooperative enterprises develops in each of the stages of the administrative process of the traditional companies, which are planning, organization, direction and control, with the only difference that the savings and credit cooperatives comply with cooperative principles and values such as mutual aid, social responsibility, democracy, equality, equity and solidarity. The objective of this research was to evaluate the process of administrative management in four selected savings and credit cooperatives from Quito city, Ecuador, were applied theoretical and empirical methods of research. From the empirical point of view, a survey was applied getting results from this process. In general, in the cooperatives evaluated, it was recognized the importance of comprehensive management, strategic planning, motivation as a key element for good job performance, the effectiveness of formal communication channels and other aspects inherent in administrative management, although there are certain deficiencies that limit the results of the cooperative activity.

Seasonality in molecular and cytometric diversity of marine bacterioplankton: the reshuffling of bacterial taxa by vertical mixing

KAUST Repository

Garcí a, Francisca C.; Alonso-Sá ez, Laura; Moran, Xose Anxelu G.; Ló pez-Urrutia, Á ngel

2015-01-01

were significantly correlated in samples from a 3.5-year monthly time-series. Both methods showed a consistent cyclical pattern in the diversity of surface bacterial communities with maximal values in winter. The analysis of the highly resolved flow

Inertia in Cooperative Remodeling

OpenAIRE

Nilsson, Jerker

1997-01-01

Which organization model is appropriate for a cooperative enterprise depends on the prerequisites in its business environment. When conditions are changing, the firm must adapt itself. The entry of Sweden, Finland, and Austria into the European Union led to radical changes for agricultural cooperation, especially for Swedish cooperatives since agricultural policy was not allowed a transitional period. After two years, Swedish cooperatives have still not adapted their organization model despit...

Self-organization in a diversity induced thermodynamics.

Science.gov (United States)

Scirè, Alessandro; Annovazzi-Lodi, Valerio

2017-01-01

In this work we show how global self-organized patterns can come out of a disordered ensemble of point oscillators, as a result of a deterministic, and not of a random, cooperative process. The resulting system dynamics has many characteristics of classical thermodynamics. To this end, a modified Kuramoto model is introduced, by including Euclidean degrees of freedom and particle polarity. The standard deviation of the frequency distribution is the disorder parameter, diversity, acting as temperature, which is both a source of motion and of disorder. For zero and low diversity, robust static phase-synchronized patterns (crystals) appear, and the problem reverts to a generic dissipative many-body problem. From small to moderate diversity crystals display vibrations followed by structure disintegration in a competition of smaller dynamic patterns, internally synchronized, each of which is capable to manage its internal diversity. In this process a huge variety of self-organized dynamic shapes is formed. Such patterns can be seen again as (more complex) oscillators, where the same description can be applied in turn, renormalizing the problem to a bigger scale, opening the possibility of pattern evolution. The interaction functions are kept local because our idea is to build a system able to produce global patterns when its constituents only interact at the bond scale. By further increasing the oscillator diversity, the dynamics becomes erratic, dynamic patterns show short lifetime, and finally disappear for high diversity. Results are neither qualitatively dependent on the specific choice of the interaction functions nor on the shape of the probability function assumed for the frequencies. The system shows a phase transition and a critical behaviour for a specific value of diversity.

Guinea pig maximization test

DEFF Research Database (Denmark)

Andersen, Klaus Ejner

1985-01-01

Guinea pig maximization tests (GPMT) with chlorocresol were performed to ascertain whether the sensitization rate was affected by minor changes in the Freund's complete adjuvant (FCA) emulsion used. Three types of emulsion were evaluated: the oil phase was mixed with propylene glycol, saline...

Cooperation and cheating in microbes

Science.gov (United States)

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.

The cooperative economy of food: Implications for human life history and physiology.

Science.gov (United States)

Kramer, Karen L

2018-04-06

The human diet has undergone substantial modifications since the emergence of modern humans and varies considerably in today's traditional societies. Despite these changes and cross-cultural differences, the human diet can be characterized by several common elements. These include diverse, high quality foods, technological complexity to acquire and process food, and the establishment of home bases for storage, processing and consumption. Together these aspects of the human diet challenge any one individual to independently meet all of his or her daily caloric needs. Humans solve this challenge through food sharing, labor exchange and the division of labor. The cooperative nature of the human diet is associated with many downstream effects on our life history and physiology. This paper overviews the constellation of traits that likely led to a cooperative economy of food, and draws on ethnographic examples to illustrate its effects on human life history and physiology. Two detailed examples using body composition, time allocation and food acquisition data show how cooperation among Savanna Pumé hunter-gatherers affects activity levels, sexual dimorphism in body fat, maturational pace and age at first birth. Copyright © 2018. Published by Elsevier Inc.

Gradient Dynamics and Entropy Production Maximization

Science.gov (United States)

Janečka, Adam; Pavelka, Michal

2018-01-01

We compare two methods for modeling dissipative processes, namely gradient dynamics and entropy production maximization. Both methods require similar physical inputs-how energy (or entropy) is stored and how it is dissipated. Gradient dynamics describes irreversible evolution by means of dissipation potential and entropy, it automatically satisfies Onsager reciprocal relations as well as their nonlinear generalization (Maxwell-Onsager relations), and it has statistical interpretation. Entropy production maximization is based on knowledge of free energy (or another thermodynamic potential) and entropy production. It also leads to the linear Onsager reciprocal relations and it has proven successful in thermodynamics of complex materials. Both methods are thermodynamically sound as they ensure approach to equilibrium, and we compare them and discuss their advantages and shortcomings. In particular, conditions under which the two approaches coincide and are capable of providing the same constitutive relations are identified. Besides, a commonly used but not often mentioned step in the entropy production maximization is pinpointed and the condition of incompressibility is incorporated into gradient dynamics.

On Maximal Non-Disjoint Families of Subsets

Directory of Open Access Journals (Sweden)

Yu. A. Zuev

2017-01-01

Full Text Available The paper studies maximal non-disjoint families of subsets of a finite set. Non-disjointness means that any two subsets of a family have a nonempty intersection. The maximality is expressed by the fact that adding a new subset to the family cannot increase its power without violating a non-disjointness condition. Studying the properties of such families is an important section of the extreme theory of sets. Along with purely combinatorial interest, the problems considered here play an important role in informatics, anti-noise coding, and cryptography.In 1961 this problem saw the light of day in the Erdos, Ko and Rado paper, which established a maximum power of the non-disjoint family of subsets of equal power. In 1974 the Erdos and Claytman publication estimated the number of maximal non-disjoint families of subsets without involving the equality of their power. These authors failed to establish an asymptotics of the logarithm of the number of such families when the power of a basic finite set tends to infinity. However, they suggested such an asymptotics as a hypothesis. A.D. Korshunov in two publications in 2003 and 2005 established the asymptotics for the number of non-disjoint families of the subsets of arbitrary powers without maximality condition of these families.The basis for the approach used in the paper to study the families of subsets is their description in the language of Boolean functions. A one-to-one correspondence between a family of subsets and a Boolean function is established by the fact that the characteristic vectors of subsets of a family are considered to be the unit sets of a Boolean function. The main theoretical result of the paper is that the maximal non-disjoint families are in one-to-one correspondence with the monotonic self-dual Boolean functions. When estimating the number of maximal non-disjoint families, this allowed us to use the result of A.A. Sapozhenko, who established the asymptotics of the number of the

Inquiry in bibliography some of the bustan`s maxim

Directory of Open Access Journals (Sweden)

sajjad rahmatian

2016-12-01

Full Text Available Sa`di is on of those poets who`s has placed a special position to preaching and guiding the people and among his works, allocated throughout the text of bustan to advice and maxim on legal and ethical various subjects. Surely, sa`di on the way of to compose this work and expression of its moral point, direct or indirect have been affected by some previous sources and possibly using their content. The main purpose of this article is that the pay review of basis and sources of bustan`s maxims and show that sa`di when expression the maxims of this work has been affected by which of the texts and works. For this purpose is tried to with search and research on the resources that have been allocated more or less to the aphorisms, to discover and extract traces of influence sa`di from their moral and didactic content. From the most important the finding of this study can be mentioned that indirect effect of some pahlavi books of maxim (like maxims of azarbad marespandan and bozorgmehr book of maxim and also noted sa`di directly influenced of moral and ethical works of poets and writers before him, and of this, sa`di`s influence from abo- shakur balkhi maxims, ferdowsi and keikavus is remarkable and noteworthy.

Can monkeys make investments based on maximized pay-off?

Directory of Open Access Journals (Sweden)

Sophie Steelandt

2011-03-01

Full Text Available Animals can maximize benefits but it is not known if they adjust their investment according to expected pay-offs. We investigated whether monkeys can use different investment strategies in an exchange task. We tested eight capuchin monkeys (Cebus apella and thirteen macaques (Macaca fascicularis, Macaca tonkeana in an experiment where they could adapt their investment to the food amounts proposed by two different experimenters. One, the doubling partner, returned a reward that was twice the amount given by the subject, whereas the other, the fixed partner, always returned a constant amount regardless of the amount given. To maximize pay-offs, subjects should invest a maximal amount with the first partner and a minimal amount with the second. When tested with the fixed partner only, one third of monkeys learned to remove a maximal amount of food for immediate consumption before investing a minimal one. With both partners, most subjects failed to maximize pay-offs by using different decision rules with each partner' quality. A single Tonkean macaque succeeded in investing a maximal amount to one experimenter and a minimal amount to the other. The fact that only one of over 21 subjects learned to maximize benefits in adapting investment according to experimenters' quality indicates that such a task is difficult for monkeys, albeit not impossible.

Maximal lattice free bodies, test sets and the Frobenius problem

DEFF Research Database (Denmark)

Jensen, Anders Nedergaard; Lauritzen, Niels; Roune, Bjarke Hammersholt

Maximal lattice free bodies are maximal polytopes without interior integral points. Scarf initiated the study of maximal lattice free bodies relative to the facet normals in a fixed matrix. In this paper we give an efficient algorithm for computing the maximal lattice free bodies of an integral m...... method is inspired by the novel algorithm by Einstein, Lichtblau, Strzebonski and Wagon and the Groebner basis approach by Roune....

Disk Density Tuning of a Maximal Random Packing.

Science.gov (United States)

Ebeida, Mohamed S; Rushdi, Ahmad A; Awad, Muhammad A; Mahmoud, Ahmed H; Yan, Dong-Ming; English, Shawn A; Owens, John D; Bajaj, Chandrajit L; Mitchell, Scott A

2016-08-01

We introduce an algorithmic framework for tuning the spatial density of disks in a maximal random packing, without changing the sizing function or radii of disks. Starting from any maximal random packing such as a Maximal Poisson-disk Sampling (MPS), we iteratively relocate, inject (add), or eject (remove) disks, using a set of three successively more-aggressive local operations. We may achieve a user-defined density, either more dense or more sparse, almost up to the theoretical structured limits. The tuned samples are conflict-free, retain coverage maximality, and, except in the extremes, retain the blue noise randomness properties of the input. We change the density of the packing one disk at a time, maintaining the minimum disk separation distance and the maximum domain coverage distance required of any maximal packing. These properties are local, and we can handle spatially-varying sizing functions. Using fewer points to satisfy a sizing function improves the efficiency of some applications. We apply the framework to improve the quality of meshes, removing non-obtuse angles; and to more accurately model fiber reinforced polymers for elastic and failure simulations.

Cooperating for assisting intelligently operators

International Nuclear Information System (INIS)

Brezillon, P.; Cases, E.; CEA Centre d'Etudes de la Vallee du Rhone, 30 - Marcoule

1995-01-01

We are in the process of an intelligent cooperative system in a nuclear plant application. The system must cooperate with an operator who accomplishes a task of supervision of a real-world process. We point out in the paper that a cooperation between a cooperative system and an operator has two modes: a waking state and a participating state. During the waking state, the system observes the operator's behavior and the consequences on the process. During the participation state, the cooperative system builds jointly with the user a solution to the problem. In our approach, the cooperation depends on the system capabilities to explain, to incrementally acquire knowledge and to make explicit the context of the cooperation. We develop these ideas in the framework of the design of the cooperative system in the nuclear plant. (authors). 22 refs., 1 fig

Cooperative Fuzzy Games Approach to Setting Target Levels of ECs in Quality Function Deployment

Directory of Open Access Journals (Sweden)

Zhihui Yang

2014-01-01

Full Text Available Quality function deployment (QFD can provide a means of translating customer requirements (CRs into engineering characteristics (ECs for each stage of product development and production. The main objective of QFD-based product planning is to determine the target levels of ECs for a new product or service. QFD is a breakthrough tool which can effectively reduce the gap between CRs and a new product/service. Even though there are conflicts among some ECs, the objective of developing new product is to maximize the overall customer satisfaction. Therefore, there may be room for cooperation among ECs. A cooperative game framework combined with fuzzy set theory is developed to determine the target levels of the ECs in QFD. The key to develop the model is the formulation of the bargaining function. In the proposed methodology, the players are viewed as the membership functions of ECs to formulate the bargaining function. The solution for the proposed model is Pareto-optimal. An illustrated example is cited to demonstrate the application and performance of the proposed approach.

Cooperative fuzzy games approach to setting target levels of ECs in quality function deployment.

Science.gov (United States)

Yang, Zhihui; Chen, Yizeng; Yin, Yunqiang

2014-01-01

Quality function deployment (QFD) can provide a means of translating customer requirements (CRs) into engineering characteristics (ECs) for each stage of product development and production. The main objective of QFD-based product planning is to determine the target levels of ECs for a new product or service. QFD is a breakthrough tool which can effectively reduce the gap between CRs and a new product/service. Even though there are conflicts among some ECs, the objective of developing new product is to maximize the overall customer satisfaction. Therefore, there may be room for cooperation among ECs. A cooperative game framework combined with fuzzy set theory is developed to determine the target levels of the ECs in QFD. The key to develop the model is the formulation of the bargaining function. In the proposed methodology, the players are viewed as the membership functions of ECs to formulate the bargaining function. The solution for the proposed model is Pareto-optimal. An illustrated example is cited to demonstrate the application and performance of the proposed approach.

An information maximization model of eye movements

Science.gov (United States)

Renninger, Laura Walker; Coughlan, James; Verghese, Preeti; Malik, Jitendra

2005-01-01

We propose a sequential information maximization model as a general strategy for programming eye movements. The model reconstructs high-resolution visual information from a sequence of fixations, taking into account the fall-off in resolution from the fovea to the periphery. From this framework we get a simple rule for predicting fixation sequences: after each fixation, fixate next at the location that minimizes uncertainty (maximizes information) about the stimulus. By comparing our model performance to human eye movement data and to predictions from a saliency and random model, we demonstrate that our model is best at predicting fixation locations. Modeling additional biological constraints will improve the prediction of fixation sequences. Our results suggest that information maximization is a useful principle for programming eye movements.

Cooperation in wireless networks principles and applications : real egoistic behavior is to cooperate!

CERN Document Server

Fitzek, Frank HP

2006-01-01

Covers the underlying principles of cooperative techniques as well as several applications demonstrating the use of such techniques in practical systems. This book also summarizes the strength of cooperation for wireless communication systems, motivating the use of cooperative techniques.

On the way towards a generalized entropy maximization procedure

International Nuclear Information System (INIS)

Bagci, G. Baris; Tirnakli, Ugur

2009-01-01

We propose a generalized entropy maximization procedure, which takes into account the generalized averaging procedures and information gain definitions underlying the generalized entropies. This novel generalized procedure is then applied to Renyi and Tsallis entropies. The generalized entropy maximization procedure for Renyi entropies results in the exponential stationary distribution asymptotically for q element of (0,1] in contrast to the stationary distribution of the inverse power law obtained through the ordinary entropy maximization procedure. Another result of the generalized entropy maximization procedure is that one can naturally obtain all the possible stationary distributions associated with the Tsallis entropies by employing either ordinary or q-generalized Fourier transforms in the averaging procedure.

Violating Bell inequalities maximally for two d-dimensional systems

International Nuclear Information System (INIS)

Chen Jingling; Wu Chunfeng; Oh, C. H.; Kwek, L. C.; Ge Molin

2006-01-01

We show the maximal violation of Bell inequalities for two d-dimensional systems by using the method of the Bell operator. The maximal violation corresponds to the maximal eigenvalue of the Bell operator matrix. The eigenvectors corresponding to these eigenvalues are described by asymmetric entangled states. We estimate the maximum value of the eigenvalue for large dimension. A family of elegant entangled states |Ψ> app that violate Bell inequality more strongly than the maximally entangled state but are somewhat close to these eigenvectors is presented. These approximate states can potentially be useful for quantum cryptography as well as many other important fields of quantum information

Social heuristics shape intuitive cooperation.

Science.gov (United States)

Rand, David G; Peysakhovich, Alexander; Kraft-Todd, Gordon T; Newman, George E; Wurzbacher, Owen; Nowak, Martin A; Greene, Joshua D

2014-04-22

Cooperation is central to human societies. Yet relatively little is known about the cognitive underpinnings of cooperative decision making. Does cooperation require deliberate self-restraint? Or is spontaneous prosociality reined in by calculating self-interest? Here we present a theory of why (and for whom) intuition favors cooperation: cooperation is typically advantageous in everyday life, leading to the formation of generalized cooperative intuitions. Deliberation, by contrast, adjusts behaviour towards the optimum for a given situation. Thus, in one-shot anonymous interactions where selfishness is optimal, intuitive responses tend to be more cooperative than deliberative responses. We test this 'social heuristics hypothesis' by aggregating across every cooperation experiment using time pressure that we conducted over a 2-year period (15 studies and 6,910 decisions), as well as performing a novel time pressure experiment. Doing so demonstrates a positive average effect of time pressure on cooperation. We also find substantial variation in this effect, and show that this variation is partly explained by previous experience with one-shot lab experiments.

Cooperative games and network structures

NARCIS (Netherlands)

Musegaas, Marieke

2017-01-01

This thesis covers various research topics involving cooperative game theory, a mathematical tool to analyze the cooperative behavior within a group of players. The focus is mainly on interrelations between operations research and cooperative game theory by analyzing specific types of cooperative

Error-rate performance analysis of cooperative OFDMA system with decode-and-forward relaying

KAUST Repository

Fareed, Muhammad Mehboob; Uysal, Murat; Tsiftsis, Theodoros A.

2014-01-01

In this paper, we investigate the performance of a cooperative orthogonal frequency-division multiple-access (OFDMA) system with decode-and-forward (DaF) relaying. Specifically, we derive a closed-form approximate symbol-error-rate expression and analyze the achievable diversity orders. Depending on the relay location, a diversity order up to (LSkD + 1) + σ M m = 1 min(LSkRm + 1, LR mD + 1) is available, where M is the number of relays, and LS kD + 1, LSkRm + 1, and LRmD + 1 are the lengths of channel impulse responses of source-to-destination, source-to- mth relay, and mth relay-to-destination links, respectively. Monte Carlo simulation results are also presented to confirm the analytical findings. © 2013 IEEE.

Error-rate performance analysis of cooperative OFDMA system with decode-and-forward relaying

KAUST Repository

Fareed, Muhammad Mehboob

2014-06-01

In this paper, we investigate the performance of a cooperative orthogonal frequency-division multiple-access (OFDMA) system with decode-and-forward (DaF) relaying. Specifically, we derive a closed-form approximate symbol-error-rate expression and analyze the achievable diversity orders. Depending on the relay location, a diversity order up to (LSkD + 1) + σ M m = 1 min(LSkRm + 1, LR mD + 1) is available, where M is the number of relays, and LS kD + 1, LSkRm + 1, and LRmD + 1 are the lengths of channel impulse responses of source-to-destination, source-to- mth relay, and mth relay-to-destination links, respectively. Monte Carlo simulation results are also presented to confirm the analytical findings. © 2013 IEEE.

What drives cooperative breeding?

Directory of Open Access Journals (Sweden)

Walter D Koenig

2017-06-01

Full Text Available Cooperative breeding, in which more than a pair of conspecifics cooperate to raise young at a single nest or brood, is widespread among vertebrates but highly variable in its geographic distribution. Particularly vexing has been identifying the ecological correlates of this phenomenon, which has been suggested to be favored in populations inhabiting both relatively stable, productive environments and in populations living under highly variable and unpredictable conditions. Griesser et al. provide a novel approach to this problem, performing a phylogenetic analysis indicating that family living is an intermediate step between nonsocial and cooperative breeding birds. They then examine the ecological and climatic conditions associated with these different social systems, concluding that cooperative breeding emerges when family living is favored in highly productive environments, followed secondarily by selection for cooperative breeding when environmental conditions deteriorate and within-year variability increases. Combined with recent work addressing the fitness consequences of cooperative breeding, Griesser et al.'s contribution stands to move the field forward by demonstrating that the evolution of complex adaptations such as cooperative breeding may only be understood when each of the steps leading to it are identified and carefully integrated.

Cooperation in Construction:

DEFF Research Database (Denmark)

Vogelius, Peter; Storgaard, Kresten

2016-01-01

The study presents a building project executed by a major Danish construction company, where cooperation and its staging were essential for achieving high productivity and competitiveness. The form of this cooperation is the main theme for the article. The contractor actively changed the communic......The study presents a building project executed by a major Danish construction company, where cooperation and its staging were essential for achieving high productivity and competitiveness. The form of this cooperation is the main theme for the article. The contractor actively changed...... the companies in the case can be understood as possessing a social capital which is enforced and united by initiatives of the main contractor. The social capital was built up and maintained through the actual constitution of cooperation already in the initial phase of bidding before the building process....... The management logic of the main contractor is interpreted as based on a sociology-inspired understanding focusing on norms and social values rather than on contractual (law) and functional (engineering) logic, which had hitherto been prevalent in Danish construction management....

Real-time topic-aware influence maximization using preprocessing.

Science.gov (United States)

Chen, Wei; Lin, Tian; Yang, Cheng

2016-01-01

Influence maximization is the task of finding a set of seed nodes in a social network such that the influence spread of these seed nodes based on certain influence diffusion model is maximized. Topic-aware influence diffusion models have been recently proposed to address the issue that influence between a pair of users are often topic-dependent and information, ideas, innovations etc. being propagated in networks are typically mixtures of topics. In this paper, we focus on the topic-aware influence maximization task. In particular, we study preprocessing methods to avoid redoing influence maximization for each mixture from scratch. We explore two preprocessing algorithms with theoretical justifications. Our empirical results on data obtained in a couple of existing studies demonstrate that one of our algorithms stands out as a strong candidate providing microsecond online response time and competitive influence spread, with reasonable preprocessing effort.

The sound of cooperation: Musical influences on cooperative behavior.

Science.gov (United States)

Kniffin, Kevin M; Yan, Jubo; Wansink, Brian; Schulze, William D

2017-03-01

Music as an environmental aspect of professional workplaces has been closely studied with respect to consumer behavior while sparse attention has been given to its relevance for employee behavior. In this article, we focus on the influence of music upon cooperative behavior within decision-making groups. Based on results from two extended 20-round public goods experiments, we find that happy music significantly and positively influences cooperative behavior. We also find a significant positive association between mood and cooperative behavior. Consequently, while our studies provide partial support for the relevance of affect in relation to cooperation within groups, we also show an independently important function of happy music that fits with a theory of synchronous and rhythmic activity as a social lubricant. More generally, our findings indicate that music and perhaps other atmospheric variables that are designed to prime consumer behavior might have comparably important effects for employees and consequently warrant closer investigation. Copyright © 2016 The Authors Journal of Organizational Behavior Published by John Wiley & Sons Ltd.

“Diversity within Diversity” - Exploring Connections between Community, Participation and Citizenship

Directory of Open Access Journals (Sweden)

Pedro D. Ferreira

2012-09-01

Full Text Available Even if recently the notions of citizenship and community have become buzzwords of very positive connotation, significant tensions underlie any ofthem: between homogeneity and difference, belonging and diversity,inclusion and exclusion and, more recently, between freedom and security.Real communities are places of cooperation and mutual recognition as muchas they are places of inevitable conflict, social control and exclusion.Following an ecological and contextual perspective, and a relationaldefinition of community, concepts such as sense of community and socialcapital are explored. An analysis of citizen’s participation in theircommunities illustrates significant dimensions of participation: power,dialogue, initiative, formality, pluralism and time. The discussion considershow these dimensions might contribute to making community organizationsturn into 'schools of democracy' (de Tocqueville 2000, and illustrates thispotential with young migrants, as long as the diversity of diverse migrantgroups is not only recognized but furthered.

The role of leadership in creating a diversity-sensitive organization.

Science.gov (United States)

Dreachslin, Janice L

2007-01-01

The opportunity for personal growth that a focus on DSO development offers leaders is compelling, as it provides and requires new experiences and new ideas. Seasoned healthcare executives and their organizations are offered the opportunity for renewal-to see things in a new light and experience the organization, the service area, and each other differently. Researchers at the Gallup Organization, based on studies of more than 50,000 leaders in diverse industries, have identified the following seven demands of leadership: visioning, maximizing values, challenging experiences, mentoring, building a constituency, making sense of experience, and knowing one's self (Conchie 2004). To meet these demands with courage and conviction in the context of diversity is, perhaps, the ultimate healthcare leadership challenge in the foreseeable future.

Transnational Research Co-operation: Opportunities and Challenges for transnational research co-operation

DEFF Research Database (Denmark)

of the NGOs have a lot of international experience (mainly in Denmark and Germany) as partners in different co-operation projects. Almost all the NGOs have recognized the important role of the scientific information in their activity. NGOs also feel the need for an easy access to required information...... for transnational co-operation like: an investigation/project concerning the driving forces behind urban development,or a co-operation in the field of wastewater reuse and minimization of wastewater loads and discharge, or a service page (internet) to search for potential partners. The governmental institutions...... in order to improve transnational cooperation are identified to be: • Search for national/international project partners • Access to existent co-operation projects or networks • Develop in common project proposals on themes requested by community groups • Exchange information/good operational practices...

Cardiorespiratory Coordination in Repeated Maximal Exercise

Directory of Open Access Journals (Sweden)

Sergi Garcia-Retortillo

2017-06-01

Full Text Available Increases in cardiorespiratory coordination (CRC after training with no differences in performance and physiological variables have recently been reported using a principal component analysis approach. However, no research has yet evaluated the short-term effects of exercise on CRC. The aim of this study was to delineate the behavior of CRC under different physiological initial conditions produced by repeated maximal exercises. Fifteen participants performed 2 consecutive graded and maximal cycling tests. Test 1 was performed without any previous exercise, and Test 2 6 min after Test 1. Both tests started at 0 W and the workload was increased by 25 W/min in males and 20 W/min in females, until they were not able to maintain the prescribed cycling frequency of 70 rpm for more than 5 consecutive seconds. A principal component (PC analysis of selected cardiovascular and cardiorespiratory variables (expired fraction of O2, expired fraction of CO2, ventilation, systolic blood pressure, diastolic blood pressure, and heart rate was performed to evaluate the CRC defined by the number of PCs in both tests. In order to quantify the degree of coordination, the information entropy was calculated and the eigenvalues of the first PC (PC1 were compared between tests. Although no significant differences were found between the tests with respect to the performed maximal workload (Wmax, maximal oxygen consumption (VO2 max, or ventilatory threshold (VT, an increase in the number of PCs and/or a decrease of eigenvalues of PC1 (t = 2.95; p = 0.01; d = 1.08 was found in Test 2 compared to Test 1. Moreover, entropy was significantly higher (Z = 2.33; p = 0.02; d = 1.43 in the last test. In conclusion, despite the fact that no significant differences were observed in the conventionally explored maximal performance and physiological variables (Wmax, VO2 max, and VT between tests, a reduction of CRC was observed in Test 2. These results emphasize the interest of CRC

Research on Cooperation Strategy of Enterprises’ Quality and Safety in Food Supply Chain

Directory of Open Access Journals (Sweden)

Jining Wang

2015-01-01

Full Text Available In order to prevent and control risk factors which harm the quality and safety of the food supply chain effectively and reduce the probability of food safety incidents, this paper investigated on some problems of the upstream and downstream enterprises of the food supply chain under the three different forms of cooperation based on the neoclassic economics and game theory method. These problems include the effectiveness of the quality and safety efforts, the profits, the effect of the losses that the food safety incidents caused on the quality efforts’ efficacy, and the social welfare comparison. Meanwhile, we constructed evolutionary game model to analyze the macro and micro factors that influenced the cooperation strategy and demonstrated the effect of diversity of decision-making parameters on evolution results based on numerical simulation. By the theoretical and simulation analysis, we found that (1 the quality efforts’ efficacy, the profits, the sensitivity coefficient of the quality efforts efficiency to the losses, and the social welfare without thinking about the externality all met their maximum under the full cooperation situation; (2 strengthening supervision over the source of the food supply chain can reduce the probability of food safety incidents; (3 macro and micro environment will be the important basis for companies’ decision-making on cooperation strategy in the food supply chain.

El culto de Maximón en Guatemala

OpenAIRE

Pédron‑Colombani, Sylvie

2009-01-01

Este artículo se enfoca en la figura de Maximón, deidad sincrética de Guatemala, en un contexto de desplazamiento de la religión católica popular por parte de las iglesias protestantes. Esta divinidad híbrida a la cual se agregan santos católicos como Judas Iscariote o el dios maya Mam, permite la apropiación de Maximón por segmentos diferenciados de la población (tanto indígena como mestiza). Permite igualmente ser símbolo de protestas sociales enmascaradas cuando se asocia Maximón con figur...

Self-consistent collective-coordinate method for ''maximally-decoupled'' collective subspace and its boson mapping: Quantum theory of ''maximally-decoupled'' collective motion

International Nuclear Information System (INIS)

Marumori, T.; Sakata, F.; Maskawa, T.; Une, T.; Hashimoto, Y.

1983-01-01

The main purpose of this paper is to develop a full quantum theory, which is capable by itself of determining a ''maximally-decoupled'' collective motion. The paper is divided into two parts. In the first part, the motivation and basic idea of the theory are explained, and the ''maximal-decoupling condition'' on the collective motion is formulated within the framework of the time-dependent Hartree-Fock theory, in a general form called the invariance principle of the (time-dependent) Schrodinger equation. In the second part, it is shown that when the author positively utilize the invariance principle, we can construct a full quantum theory of the ''maximally-decoupled'' collective motion. This quantum theory is shown to be a generalization of the kinematical boson-mapping theories so far developed, in such a way that the dynamical ''maximal-decoupling condition'' on the collective motion is automatically satisfied

Real-time control strategy to maximize hybrid electric vehicle powertrain efficiency

International Nuclear Information System (INIS)

Shabbir, Wassif; Evangelou, Simos A.

2014-01-01

Highlights: • An off-line local control is proposed for real-time HEV energy management. • Powertrain efficiencies are studied to produce a unified objective function. • Penalty function is designed to ensure charge sustaining operation. • Implementation by storing optimal power share in a two-dimensional control map. • Proposed control improved fuel economy by up to 20% compared to conventional control. - Abstract: The proposed supervisory control system (SCS) uses a control map to maximize the powertrain efficiency of a hybrid electric vehicle (HEV) in real-time. The paper presents the methodology and structure of the control, including a novel, comprehensive and unified expression for the overall powertrain efficiency that considers the engine-generator set and the battery in depth as well as the power electronics. A control map is then produced with instructions for the optimal power share between the engine branch and battery branch of the vehicle such that the powertrain efficiency is maximized. This map is computed off-line and can thereafter be operated in real-time at very low computational cost. A charge sustaining factor is also developed and introduced to ensure the SCS operates the vehicle within desired SOC bounds. This SCS is then tested and benchmarked against two conventional control strategies in a high-fidelity vehicle model, representing a series HEV. Extensive simulation results are presented for repeated cycles of a diverse range of standard driving cycles, showing significant improvements in fuel economy (up to 20%) and less aggressive use of the battery

Cooperative Monitoring Center Occasional Paper/8: Cooperative Border Security for Jordan: Assessment and Options

Energy Technology Data Exchange (ETDEWEB)

Qojas, M.

1999-03-01

This document is an analysis of options for unilateral and cooperative action to improve the security of Jordan's borders. Sections describe the current political, economic, and social interactions along Jordan's borders. Next, the document discusses border security strategy for cooperation among neighboring countries and the adoption of confidence-building measures. A practical cooperative monitoring system would consist of hardware for early warning, command and control, communications, and transportation. Technical solutions can expand opportunities for the detection and identification of intruders. Sensors (such as seismic, break-wire, pressure-sensing, etc.) can warn border security forces of intrusion and contribute to the identification of the intrusion and help formulate the response. This document describes conceptual options for cooperation, offering three scenarios that relate to three hypothetical levels (low, medium, and high) of cooperation. Potential cooperative efforts under a low cooperation scenario could include information exchanges on military equipment and schedules to prevent misunderstandings and the establishment of protocols for handling emergency situations or unusual circumstances. Measures under a medium cooperation scenario could include establishing joint monitoring groups for better communications, with hot lines and scheduled meetings. The high cooperation scenario describes coordinated responses, joint border patrols, and sharing border intrusion information. Finally, the document lists recommendations for organizational, technical, and operational initiatives that could be applicable to the current situation.

The intermediate disturbance hypothesis applies to tropical forests, but disturbance contributes little to tree diversity.

Science.gov (United States)

Bongers, Frans; Poorter, Lourens; Hawthorne, William D; Sheil, Douglas

2009-08-01

The intermediate disturbance hypothesis (IDH) predicts local species diversity to be maximal at an intermediate level of disturbance. Developed to explain species maintenance and diversity patterns in species-rich ecosystems such as tropical forests, tests of IDH in tropical forest remain scarce, small-scale and contentious. We use an unprecedented large-scale dataset (2504 one-hectare plots and 331,567 trees) to examine whether IDH explains tree diversity variation within wet, moist and dry tropical forests, and we analyse the underlying mechanism by determining responses within functional species groups. We find that disturbance explains more variation in diversity of dry than wet tropical forests. Pioneer species numbers increase with disturbance, shade-tolerant species decrease and intermediate species are indifferent. While diversity indeed peaks at intermediate disturbance levels little variation is explained outside dry forests, and disturbance is less important for species richness patterns in wet tropical rain forests than previously thought.

A test of vertical economies for non-vertically integrated firms: The case of rural electric cooperatives

International Nuclear Information System (INIS)

Greer, Monica L.

2008-01-01

This paper seeks to evaluate unrealized economies of vertical integration for rural electric cooperatives. Given the well-established network economies that are inherent in the generation, transmission, and distribution of electricity, the coops long-standing choice of market structure is questionable (especially if their strategy is welfare maximization). Organized as either generation-and-transmission or distribution-only, the traditional measures of vertical economies will not work. Thus, I have devised an alternative method by which to measure such economies and find that, on average, cost savings in excess of 39% could have been realized had the coops adopted a vertically integrated structure. (author)

Patterns of cooperation: fairness and coordination in networks of interacting agents

Science.gov (United States)

Do, Anne-Ly; Rudolf, Lars; Gross, Thilo

2010-06-01

We study the self-assembly of a complex network of collaborations among self-interested agents. The agents can maintain different levels of cooperation with different partners. Further, they continuously, selectively and independently adapt the amount of resources allocated to each of their collaborations in order to maximize the obtained payoff. We show analytically that the system approaches a state in which the agents make identical investments, and links produce identical benefits. Despite this high degree of social coordination, some agents manage to secure privileged topological positions in the network, enabling them to extract high payoffs. Our analytical investigations provide a rationale for the emergence of unidirectional non-reciprocal collaborations and different responses to the withdrawal of a partner from an interaction that have been reported in the psychological literature.

Maximizing Conservation and Production with Intensive Forest Management: It's All About Location

Science.gov (United States)

Tittler, Rebecca; Filotas, Élise; Kroese, Jasmin; Messier, Christian

2015-11-01

Functional zoning has been suggested as a way to balance the needs of a viable forest industry with those of healthy ecosystems. Under this system, part of the forest is set aside for protected areas, counterbalanced by intensive and extensive management of the rest of the forest. Studies indicate this may provide adequate timber while minimizing road construction and favoring the development of large mature and old stands. However, it is unclear how the spatial arrangement of intensive management areas may affect the success of this zoning. Should these areas be agglomerated or dispersed throughout the forest landscape? Should managers prioritize (a) proximity to existing roads, (b) distance from protected areas, or (c) site-specific productivity? We use a spatially explicit landscape simulation model to examine the effects of different spatial scenarios on landscape structure, connectivity for native forest wildlife, stand diversity, harvest volume, and road construction: (1) random placement of intensive management areas, and (2-8) all possible combinations of rules (a)-(c). Results favor the agglomeration of intensive management areas. For most wildlife species, connectivity was the highest when intensive management was far from the protected areas. This scenario also resulted in relatively high harvest volumes. Maximizing distance of intensive management areas from protected areas may therefore be the best way to maximize the benefits of intensive management areas while minimizing their potentially negative effects on forest structure and biodiversity.

The story of technical cooperation

International Nuclear Information System (INIS)

Park, Yang Taek

1989-09-01

This book gives descriptions of technical cooperation, which is about why does technology transfer?, process of technology transfer with model, decisive cause and cooperation of technology transfer, cost and effect of technology transfer, historical experience of technology transfer, cases of technology transfer by field such as rubber tire, medicine and computer industry and automobile industry, technology transfer process and present condition of technical cooperation, and strategy for rising of technical cooperation : selection of technology for object of cooperation and development of human resources.

High frequency of extra-pair paternity in an urban population of Cooper's Hawks

Science.gov (United States)

Rosenfield, Robert N.; Sonsthagen, Sarah A.; Stout, William C.; Talbot, Sandra L.

2015-01-01

Raptors exhibit some of the highest rates of intra-pair copulations among birds, perhaps in an attempt by males to reduce the risk of being cuckolded. Indeed, the frequency of extra-pair fertilizations reported in studies of raptors to date is relatively low (0-11.2%). Socially monogamous Cooper's Hawks (Accipiter cooperii) exhibit one of the highest copulation rates among birds, yet there are no published accounts of extra-pair copulations (or paternity). We studied a population of Cooper's Hawks in Milwaukee, Wisconsin, during three breeding seasons (2003, 2004, and 2007), examining the possible effects of age (1 yr old vs. ≥ 2 yr old), adult mass, and brood size on the frequency of extra-pair paternity (EPP). We found that 19.3% of nestlings (N = 27/140) were extra-pair young (EPY), and 34% of all broods (N = 15/44) had at least one EPY. The sires of the EPY in our study were identified for only two broods, suggesting that floater males may have engaged in extra-pair copulations with territorial females. We found that brood size was a good predictor of the occurrence of EPP (EPP) in nests, but adult mass and female age were not. To our knowledge, these possible correlates of the occurrence of EPP in raptors had not previously been investigated. Male Cooper's Hawks provide food for females during the pre-nesting period, and delivery of food is, in contrast to other raptor species, typically followed by copulation. Thus, one possible explanation of the relatively high rates of EPP in our study is that females might accept or even solicit extra-pair copulations from males other than their mates as a means of maximizing energy intake for egg production. Such behavior might be particularly likely in our study area, i.e., a food-rich urban setting with a high breeding density of Cooper's Hawks.

Approaches to Building Teacher-Parent Cooperation

Directory of Open Access Journals (Sweden)

Franc Cankar

2012-01-01

Full Text Available The purpose of this study was to explore the areas of cooperation inwhich parent and teacher expectations were the same and where they differed. Data were obtained from a sample of 55 randomly selected primary schools. We analyzed school-to home communications, parentalinfluence on school decisions, and parent involvement in different school activities. At the same time, we also explored building cooperation among the teachers, students, and their parents, within the framework of the program ‘Reading and Conversation’. The findings indicated that the third- and ninth- grade lead teachers were mostly in agreement about the importance of parent involvement and as such represented a fairly homogenous group. The third-grade lead teachers were more open about actual involvement of parents in instruction than their ninth-grade colleagues, who were more cautious and restrained. In contrast to the lead teachers who represented a relatively narrow professional group, parents’ views were much more diverse. Parental education was the best predictor of their readiness to become involved in the life and work of their children’s school. Whether the area in which the families lived was urban or suburban did not make any difference. The evaluation of the one-year ‘Reading and Conversation’ programme revealed increases in parents’motivation to collaborate with the school as a consequence of the program’s approach to work, as well as improvement in mutual relationships and dialogue.

Game Theoretic Analysis of Cooperative Message Forwarding in Opportunistic Mobile Networks.

Science.gov (United States)

Pal, Sujata; Saha, Barun Kumar; Misra, Sudip

2017-12-01

In cooperative communication, a set of players forming a coalition ensures communal behavior among themselves by helping one another in message forwarding. Opportunistic mobile networks (OMNs) require multihop communications for transferring messages from the source to the destination nodes. However, noncooperative nodes only forward their own messages to others, and drop others' messages upon receiving them. So, the message delivery overhead increases in OMN. For minimizing the overhead and maximizing the delivery rate, we propose two coalition-based cooperative schemes: 1) simple coalition formation (SCF) and 2) overlapping coalition formation (OCF) game. In SCF, we consider the presence of a central information center, whereas OCF is a fully distributed scheme. In SCF, coalitions are disjoint, whereas in OCF, a node may be the member of multiple coalitions at the same time. All nodes in a coalition help each other cooperatively by forwarding group messages to the intermediate or destination nodes. The goal of the nodes is to achieve high success rate in delivering messages. The proposed SCF scheme is cohesive, in which disjoint coalitions always combine to form grand coalition. In OCF, a node reaches a stable grand coalition when all the nodes of the OMN are members of overlapping coalition of the node. No node gains by deviating from the grand coalition in SCF and OCF. Simulation results based on synthetic mobility model and real-life traces show that the message delivery ratio of OMNs increase by up to 67%, as compared to the noncooperative scenario. Moreover, the message overhead ratio using the proposed coalition-based schemes reduces by up to about (1/3)rd of that of the noncooperative communication scheme.

Assessment of the Maximal Split-Half Coefficient to Estimate Reliability

Science.gov (United States)

Thompson, Barry L.; Green, Samuel B.; Yang, Yanyun

2010-01-01

The maximal split-half coefficient is computed by calculating all possible split-half reliability estimates for a scale and then choosing the maximal value as the reliability estimate. Osburn compared the maximal split-half coefficient with 10 other internal consistency estimates of reliability and concluded that it yielded the most consistently…

What is a cooperative?

Science.gov (United States)

Kimberly Zeuli

2006-01-01

Groups of individuals throughout time have worked together in pursuit of common goals. The earliest forms of hunting and agriculture required a great deal of cooperation among humans. Although the word "cooperative" can be applied to many different types of group activities, in this publication it refers to a formal business model. Cooperative businesses are...

Which Individuals To Choose To Update the Reference Population? Minimizing the Loss of Genetic Diversity in Animal Genomic Selection Programs

Directory of Open Access Journals (Sweden)

Sonia E. Eynard

2018-01-01

Full Text Available Genomic selection (GS is commonly used in livestock and increasingly in plant breeding. Relying on phenotypes and genotypes of a reference population, GS allows performance prediction for young individuals having only genotypes. This is expected to achieve fast high genetic gain but with a potential loss of genetic diversity. Existing methods to conserve genetic diversity depend mostly on the choice of the breeding individuals. In this study, we propose a modification of the reference population composition to mitigate diversity loss. Since the high cost of phenotyping is the limiting factor for GS, our findings are of major economic interest. This study aims to answer the following questions: how would decisions on the reference population affect the breeding population, and how to best select individuals to update the reference population and balance maximizing genetic gain and minimizing loss of genetic diversity? We investigated three updating strategies for the reference population: random, truncation, and optimal contribution (OC strategies. OC maximizes genetic merit for a fixed loss of genetic diversity. A French Montbéliarde dairy cattle population with 50K SNP chip genotypes and simulations over 10 generations were used to compare these different strategies using milk production as the trait of interest. Candidates were selected to update the reference population. Prediction bias and both genetic merit and diversity were measured. Changes in the reference population composition slightly affected the breeding population. Optimal contribution strategy appeared to be an acceptable compromise to maintain both genetic gain and diversity in the reference and the breeding populations.

Which Individuals To Choose To Update the Reference Population? Minimizing the Loss of Genetic Diversity in Animal Genomic Selection Programs.

Science.gov (United States)

Eynard, Sonia E; Croiseau, Pascal; Laloë, Denis; Fritz, Sebastien; Calus, Mario P L; Restoux, Gwendal

2018-01-04

Genomic selection (GS) is commonly used in livestock and increasingly in plant breeding. Relying on phenotypes and genotypes of a reference population, GS allows performance prediction for young individuals having only genotypes. This is expected to achieve fast high genetic gain but with a potential loss of genetic diversity. Existing methods to conserve genetic diversity depend mostly on the choice of the breeding individuals. In this study, we propose a modification of the reference population composition to mitigate diversity loss. Since the high cost of phenotyping is the limiting factor for GS, our findings are of major economic interest. This study aims to answer the following questions: how would decisions on the reference population affect the breeding population, and how to best select individuals to update the reference population and balance maximizing genetic gain and minimizing loss of genetic diversity? We investigated three updating strategies for the reference population: random, truncation, and optimal contribution (OC) strategies. OC maximizes genetic merit for a fixed loss of genetic diversity. A French Montbéliarde dairy cattle population with 50K SNP chip genotypes and simulations over 10 generations were used to compare these different strategies using milk production as the trait of interest. Candidates were selected to update the reference population. Prediction bias and both genetic merit and diversity were measured. Changes in the reference population composition slightly affected the breeding population. Optimal contribution strategy appeared to be an acceptable compromise to maintain both genetic gain and diversity in the reference and the breeding populations. Copyright © 2018 Eynard et al.

Learning curves for mutual information maximization

International Nuclear Information System (INIS)

Urbanczik, R.

2003-01-01

An unsupervised learning procedure based on maximizing the mutual information between the outputs of two networks receiving different but statistically dependent inputs is analyzed [S. Becker and G. Hinton, Nature (London) 355, 161 (1992)]. For a generic data model, I show that in the large sample limit the structure in the data is recognized by mutual information maximization. For a more restricted model, where the networks are similar to perceptrons, I calculate the learning curves for zero-temperature Gibbs learning. These show that convergence can be rather slow, and a way of regularizing the procedure is considered

Maximizing potential for impact: Measuring and addressing issues of sharing and diversion in MAM management programs

International Nuclear Information System (INIS)

Rogers, Beatrice; Webb, Patrick; Marcus, Shelley; Maganga, Gray; Ashong, Joseph; Jayson, Lauren

2014-01-01

Programs to prevent and treat moderate acute malnutrition (MAM) commonly depend on providing supplementary foods to children. The Prevention of Malnutrition in Children Under Two Years of Age (PM2A) approach recommends providing nutritional supplements to pregnant and lactating women and to children six months to two years; some treatment programs reach older children and may provide family rations. Typically, the supplements used in such programs are variants of corn-soy blend (CSB), a micronutrient-enhanced blended food cooked as porridge, sometimes mixed with oil, or a lipid-based nutritional supplement (LNS). A comprehensive review of USAID-supported programs found that the size of the CSB ration targeting children ranged from 17.5g to 400g/ day; one reason for this disparity was differing assumptions about sharing of supplementary food, from none to equal sharing among all household members. WFP bases its ration calculation on the presumed need to provide twice the ration intended for the target child, to account for sharing. Expectations of sharing are thus a critical determinant of the amount of food needed to ensure that the target child receives an effective dose. Little empirical information is available about sharing supplementary foods, and the majority of such studies have appeared in the non-refereed literature. What literature exists suggests that sharing of supplementary food, at least among children in the household, is the norm. There is little evidence that one type of food is more likely to be shared than another (e.g., that LNS shows different patterns of sharing from CSB variants or that the CSBs vary), and little systematic evidence concerning their perception as a food or a medical treatment (or both). Factors affecting the degree of sharing or diversion of the supplement may include household composition, food insecurity, effectiveness of social and behavioural communication, mother’s involvement in child feeding, child age, desirability

Breakdown of maximality conjecture in continuous phase transitions

International Nuclear Information System (INIS)

Mukamel, D.; Jaric, M.V.

1983-04-01

A Landau-Ginzburg-Wilson model associated with a single irreducible representation which exhibits an ordered phase whose symmetry group is not a maximal isotropy subgroup of the symmetry group of the disordered phase is constructed. This example disproves the maximality conjecture suggested in numerous previous studies. Below the (continuous) transition, the order parameter points along a direction which varies with the temperature and with the other parameters which define the model. An extension of the maximality conjecture to reducible representations was postulated in the context of Higgs symmetry breaking mechanism. Our model can also be extended to provide a counter example in these cases. (author)

Maximizers versus satisficers: Decision-making styles, competence, and outcomes

OpenAIRE

Andrew M. Parker; Wändi Bruine de Bruin; Baruch Fischhoff

2007-01-01

Our previous research suggests that people reporting a stronger desire to maximize obtain worse life outcomes (Bruine de Bruin et al., 2007). Here, we examine whether this finding may be explained by the decision-making styles of self-reported maximizers. Expanding on Schwartz et al.\\ (2002), we find that self-reported maximizers are more likely to show problematic decision-making styles, as evidenced by self-reports of less behavioral coping, greater dependence on others when making decision...

IMNN: Information Maximizing Neural Networks

Science.gov (United States)

Charnock, Tom; Lavaux, Guilhem; Wandelt, Benjamin D.

2018-04-01

This software trains artificial neural networks to find non-linear functionals of data that maximize Fisher information: information maximizing neural networks (IMNNs). As compressing large data sets vastly simplifies both frequentist and Bayesian inference, important information may be inadvertently missed. Likelihood-free inference based on automatically derived IMNN summaries produces summaries that are good approximations to sufficient statistics. IMNNs are robustly capable of automatically finding optimal, non-linear summaries of the data even in cases where linear compression fails: inferring the variance of Gaussian signal in the presence of noise, inferring cosmological parameters from mock simulations of the Lyman-α forest in quasar spectra, and inferring frequency-domain parameters from LISA-like detections of gravitational waveforms. In this final case, the IMNN summary outperforms linear data compression by avoiding the introduction of spurious likelihood maxima.

Neutrino mass textures with maximal CP violation

International Nuclear Information System (INIS)

Aizawa, Ichiro; Kitabayashi, Teruyuki; Yasue, Masaki

2005-01-01

We show three types of neutrino mass textures, which give maximal CP violation as well as maximal atmospheric neutrino mixing. These textures are described by six real mass parameters: one specified by two complex flavor neutrino masses and two constrained ones and the others specified by three complex flavor neutrino masses. In each texture, we calculate mixing angles and masses, which are consistent with observed data, as well as Majorana CP phases

Scandinavian Cooperative Advantage

DEFF Research Database (Denmark)

Strand, Robert; Freeman, R. Edward

2015-01-01

. We conclude by endorsing the expression “Scandinavian cooperative advantage” in an effort to draw attention to the Scandinavian context and encourage the field of strategic management to shift its focus from achieving a competitive advantage toward achieving a cooperative advantage....

Milk marketing under cooperative and non-cooperative marketing channels: Evidence from west Bengal

Directory of Open Access Journals (Sweden)

Sarker Debnarayan

2010-01-01

Full Text Available The present study is an attempt to empirically investigate the price spread, marketing costs, marketing margins, marketing efficiency, and profit efficiency among market middlemen under cooperative and non-cooperative marketing channels in the domestic trade market of liquid milk in West Bengal. One of the important findings of this study is that, although the inter-market (and intramarket price variation for liquid milk under the cooperative marketing agency in not far from uniformity, and all marketing agencies under cooperative channels receive much lower abnormal profit per unit of milk as compared with non-cooperative channels, the former fails to provide much economic benefit, either to the producer or to the consumer, because of the burden of much higher fixed cost per unit of liquid milk.

Animal ecosystem engineers modulate the diversity-invasibility relationship.

Directory of Open Access Journals (Sweden)

Nico Eisenhauer

Full Text Available Invasions of natural communities by non-indigenous species are currently rated as one of the most important global-scale threats to biodiversity. Biodiversity itself is known to reduce invasions and increase stability. Disturbances by ecosystem engineers affect the distribution, establishment, and abundance of species but this has been ignored in studies on diversity-invasibility relationships.We determined natural plant invasion into 46 plots varying in the number of plant species (1, 4, and 16 and plant functional groups (1, 2, 3, and 4 for three years beginning two years after the establishment of the Jena Experiment. We sampled subplots where earthworms were artificially added and others where earthworm abundance was reduced. We also performed a seed-dummy experiment to investigate the role of earthworms as secondary seed dispersers along a plant diversity gradient. Horizontal dispersal and burial of seed dummies were significantly reduced in subplots where earthworms were reduced in abundance. Seed dispersal by earthworms decreased with increasing plant species richness and presence of grasses but increased in presence of small herbs. These results suggest that dense vegetation inhibits the surface activity of earthworms. Further, there was a positive relationship between the number of earthworms and the number and diversity of invasive plants. Hence, earthworms decreased the stability of grassland communities against plant invasion.Invasibility decreased and stability increased with increasing plant diversity and, most remarkably, earthworms modulated the diversity-invasibility relationship. While the impacts of earthworms were unimportant in low diverse (low earthworm densities and high diverse (high floral structural complexity plant communities, earthworms decreased the stability of intermediate diverse plant communities against plant invasion. Overall, the results document that fundamental processes in plant communities like plant seed

Comparison of changes in the mobility of the pelvic floor muscle on during the abdominal drawing-in maneuver, maximal expiration, and pelvic floor muscle maximal contraction

OpenAIRE

Jung, Halim; Jung, Sangwoo; Joo, Sunghee; Song, Changho

2016-01-01

[Purpose] The purpose of this study was to compare changes in the mobility of the pelvic floor muscle during the abdominal drawing-in maneuver, maximal expiration, and pelvic floor muscle maximal contraction. [Subjects] Thirty healthy adults participated in this study (15 men and 15 women). [Methods] All participants performed a bridge exercise and abdominal curl-up during the abdominal drawing-in maneuver, maximal expiration, and pelvic floor muscle maximal contraction. Pelvic floor mobility...

Group Cooperation without Group Selection: Modest Punishment Can Recruit Much Cooperation.

Science.gov (United States)

Krasnow, Max M; Delton, Andrew W; Cosmides, Leda; Tooby, John

2015-01-01

Humans everywhere cooperate in groups to achieve benefits not attainable by individuals. Individual effort is often not automatically tied to a proportionate share of group benefits. This decoupling allows for free-riding, a strategy that (absent countermeasures) outcompetes cooperation. Empirically and formally, punishment potentially solves the evolutionary puzzle of group cooperation. Nevertheless, standard analyses appear to show that punishment alone is insufficient, because second-order free riders (those who cooperate but do not punish) can be shown to outcompete punishers. Consequently, many have concluded that other processes, such as cultural or genetic group selection, are required. Here, we present a series of agent-based simulations that show that group cooperation sustained by punishment easily evolves by individual selection when you introduce into standard models more biologically plausible assumptions about the social ecology and psychology of ancestral humans. We relax three unrealistic assumptions of past models. First, past models assume all punishers must punish every act of free riding in their group. We instead allow punishment to be probabilistic, meaning punishers can evolve to only punish some free riders some of the time. This drastically lowers the cost of punishment as group size increases. Second, most models unrealistically do not allow punishment to recruit labor; punishment merely reduces the punished agent's fitness. We instead realistically allow punished free riders to cooperate in the future to avoid punishment. Third, past models usually restrict agents to interact in a single group their entire lives. We instead introduce realistic social ecologies in which agents participate in multiple, partially overlapping groups. Because of this, punitive tendencies are more expressed and therefore more exposed to natural selection. These three moves toward greater model realism reveal that punishment and cooperation easily evolve by

Group Cooperation without Group Selection: Modest Punishment Can Recruit Much Cooperation.

Directory of Open Access Journals (Sweden)

Max M Krasnow

Full Text Available Humans everywhere cooperate in groups to achieve benefits not attainable by individuals. Individual effort is often not automatically tied to a proportionate share of group benefits. This decoupling allows for free-riding, a strategy that (absent countermeasures outcompetes cooperation. Empirically and formally, punishment potentially solves the evolutionary puzzle of group cooperation. Nevertheless, standard analyses appear to show that punishment alone is insufficient, because second-order free riders (those who cooperate but do not punish can be shown to outcompete punishers. Consequently, many have concluded that other processes, such as cultural or genetic group selection, are required. Here, we present a series of agent-based simulations that show that group cooperation sustained by punishment easily evolves by individual selection when you introduce into standard models more biologically plausible assumptions about the social ecology and psychology of ancestral humans. We relax three unrealistic assumptions of past models. First, past models assume all punishers must punish every act of free riding in their group. We instead allow punishment to be probabilistic, meaning punishers can evolve to only punish some free riders some of the time. This drastically lowers the cost of punishment as group size increases. Second, most models unrealistically do not allow punishment to recruit labor; punishment merely reduces the punished agent's fitness. We instead realistically allow punished free riders to cooperate in the future to avoid punishment. Third, past models usually restrict agents to interact in a single group their entire lives. We instead introduce realistic social ecologies in which agents participate in multiple, partially overlapping groups. Because of this, punitive tendencies are more expressed and therefore more exposed to natural selection. These three moves toward greater model realism reveal that punishment and cooperation

Spontaneous cooperation for prosocials, but not for proselfs: Social value orientation moderates spontaneous cooperation behavior

Science.gov (United States)

Mischkowski, Dorothee; Glöckner, Andreas

2016-01-01

Cooperation is essential for the success of societies and there is an ongoing debate whether individuals have therefore developed a general spontaneous tendency to cooperate or not. Findings that cooperative behavior is related to shorter decision times provide support for the spontaneous cooperation effect, although contrary results have also been reported. We show that cooperative behavior is better described as person × situation interaction, in that there is a spontaneous cooperation effect for prosocial but not for proself persons. In three studies, one involving population representative samples from the US and Germany, we found that cooperation in a public good game is dependent on an interaction between individuals’ social value orientation and decision time. Increasing deliberation about the dilemma situation does not affect persons that are selfish to begin with, but it is related to decreasing cooperation for prosocial persons that gain positive utility from outcomes of others and score high on the related general personality trait honesty/humility. Our results demonstrate that the spontaneous cooperation hypothesis has to be qualified in that it is limited to persons with a specific personality and social values. Furthermore, they allow reconciling conflicting previous findings by identifying an important moderator for the effect. PMID:26876773

Extending the Cooperative Phenotype: Assessing the Stability of Cooperation across Countries.

Science.gov (United States)

Reigstad, Amanda G; Strømland, Eirik A; Tinghög, Gustav

2017-01-01

This paper studies whether individual cooperation is stable across settings and over time. Involving more than 7,000 subjects on two different continents, this study documents positive correlation in cooperative behavior across economic games in Norway, Sweden, Austria, and the United States. The game measures also correlate with a tendency to make deontological judgments in moral dilemmas, and display of general trust toward strangers. Using time-variation in the data, we test whether temporal stability of behavior is similar in the United States and Norway, and find similar stability estimates for both the American and Norwegian samples. The findings here provide further evidence of the existence of a stable behavioral inclination toward prosociality - a "cooperative phenotype," as it has recently been termed. Also in line with previous research, we find that punishment and cooperation seem to be uncorrelated.

Excited cooper pairs

Energy Technology Data Exchange (ETDEWEB)

Lopez-Arrietea, M. G.; Solis, M. A.; De Llano, M. [Universidad Nacional Autonoma de Mexico, Mexico, D.F (Mexico)

2001-02-01

Excited cooper pairs formed in a many-fermion system are those with nonzero total center-of mass momentum (CMM). They are normally neglected in the standard Bardeen-Cooper-Schrieffer (BCS) theory of superconductivity for being too few compared with zero CMM pairs. However, a Bose-Einstein condensation picture requires both zero and nonzero CMM pairs. Assuming a BCS model interaction between fermions we determine the populations for all CMM values of Cooper pairs by actually calculating the number of nonzero-CMM pairs relative to that of zero-CMM ones in both 2D and 3D. Although this ratio decreases rapidly with CMM, the number of Cooper pairs for any specific CMM less than the maximum (or breakup of the pair) momentum turns out to be typically larger than about 95% of those with zero-CMM at zero temperature T. Even at T {approx}100 K this fraction en 2D is still as large as about 70% for typical quasi-2D cuprate superconductor parameters. [Spanish] Los pares de cooper excitados formados en un sistema de muchos electrones, son aquellos con momentos de centro de masa (CMM) diferente de cero. Normalmente estos no son tomados en cuenta en la teoria estandar de la superconductividad de Bardeen-Cooper-Schrieffer (BCS) al suponer que su numero es muy pequeno comparados con los pares de centro de masa igual a cero. Sin embargo, un esquema de condensacion Bose-Einstein requiere de ambos pares, con CMM cero y diferente de cero. Asumiendo una interaccion modelo BCS entre los fermiones, determinamos la poblacion de pares cooper con cada uno de todos los posibles valores del CMM calculando el numero de pares con momentos de centro de masa diferente de cero relativo a los pares de CMM igual a cero, en 2D y 3D. Aunque esta razon decrece rapidamente con el CMM, el numero de pares de cooper para cualquier CMM especifico menor que el momento maximo (o rompimiento de par) es tipicamente mas grande que el 95% de aquellos con CMM cero. Aun a T {approx}100 K esta fraccion en 2D es

Boosting Female Ambition: How College Diversity Impacts Graduate Degree Aspirations of Women. ASHE Annual Meeting Paper.

Science.gov (United States)

Tsui, Lisa

In seeking to expand research on the actual effects of diversity on college students, this study investigated whether various multi-cultural and feminism-related variables at the individual, peer, and institutional levels significantly influenced educational degree ambitions among women. The study used data from the Cooperative Institutional…

Threshold-Based Relay Selection for Detect-and-Forward Relaying in Cooperative Wireless Networks

Directory of Open Access Journals (Sweden)

Fan Yijia

2010-01-01

Full Text Available This paper studies two-hop cooperative demodulate-and-forward relaying using multiple relays in wireless networks. A threshold based relay selection scheme is considered, in which the reliable relays are determined by comparing source-relay SNR to a threshold, and one of the reliable relays is selected by the destination based on relay-destination SNR. The exact bit error rate of this scheme is derived, and a simple threshold function is proposed. It is shown that the network achieves full diversity order ( under the proposed threshold, where is the number of relays in the network. Unlike some other full diversity achieving protocols in the literature, the requirement that the instantaneous/average SNRs of the source-relay links be known at the destination is eliminated using the appropriate SNR threshold.

R&D Cooperation and Knowledge Spillover Effects for Sustainable Business Innovation in the Chemical Industry

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Petr Hájek

2018-04-01

Full Text Available This paper investigates the influence of research and development (R&D cooperation on the creation of spillover effects for sustainable firms in the chemical industry. We explore the evidence for the origin of knowledge spillovers derived from cooperation amongst firms and universities and R&D organizations as well as to test the influence of internal/external financial support on these effects. The results confirm that when firms acquire knowledge from internal sources, this leads to increased innovation and sustainable performance. We have proved that internal expenditure results in increased internal knowledge spillovers. These findings may be specific for Central and Eastern (CEE transition countries, indicating their efforts to build path-dependent structures based on knowledge institutions and businesses as well as knowledge networks. However, this study also provides a more “global” contribution to the knowledge spillover effect theory. It shows that a firm’s cooperation both with universities and with other firms promotes different types of knowledge spillovers and can affect diverse modes of sustainable activities in innovation.

International co-operation

International Nuclear Information System (INIS)

1997-01-01

In 1996, Nuclear Regulatory Authority of the Slovak Republic (NRA SR) ensured the Slovak Republic (SR) obligations with relation to the international agreements and with the SR membership in the IAEA.International co-operation has been ensured on the basis of the bilateral international agreements. With the Ministry of Foreign Affairs co-operation, the SR fulfilled its financial obligations to this organization in due time and in the full scope. Representing Central and Eastern Europe interest in the Board of Governors, the SR participation in the highest executive in the highest executive authority was finished in 1996.The Board of Governors Vice-chairman position was executed by NRA SR Chairman. 5 national and 6 regional technical co-operation and assistance projects were realized in 1996. 12 organizations participated in these projects and accordingly 104 experts took part in training programmes, scientific visits or as the mission members abroad. Besides, Slovak experts participated at work of technical advisory and consultation groups with the significant assistance. In the framework of IAEA co-operation, the SR was visited by 11 expert missions formed by 28 experts from 19 countries including IAEA. Slovak organizations, namely institutes of the Academy of Sciences, Slovak research centres and universities participated in IAEA scientific and research activities through NRA SR. 15 scientific contracts in total were approved and realized and these contracts are utilized as supplementary financing of the own scientific and research projects. Other international co-operation and regional co-operation activities of the NRA SR in 1996 are reviewed

Maximally-localized position, Euclidean path-integral, and thermodynamics in GUP quantum mechanics

Science.gov (United States)

Bernardo, Reginald Christian S.; Esguerra, Jose Perico H.

2018-04-01

In dealing with quantum mechanics at very high energies, it is essential to adapt to a quasiposition representation using the maximally-localized states because of the generalized uncertainty principle. In this paper, we look at maximally-localized states as eigenstates of the operator ξ = X + iβP that we refer to as the maximally-localized position. We calculate the overlap between maximally-localized states and show that the identity operator can be expressed in terms of the maximally-localized states. Furthermore, we show that the maximally-localized position is diagonal in momentum-space and that the maximally-localized position and its adjoint satisfy commutation and anti-commutation relations reminiscent of the harmonic oscillator commutation and anti-commutation relations. As application, we use the maximally-localized position in developing the Euclidean path-integral and introduce the compact form of the propagator for maximal localization. The free particle momentum-space propagator and the propagator for maximal localization are analytically evaluated up to quadratic-order in β. Finally, we obtain a path-integral expression for the partition function of a thermodynamic system using the maximally-localized states. The partition function of a gas of noninteracting particles is evaluated. At temperatures exceeding the Planck energy, we obtain the gas' maximum internal energy N / 2 β and recover the zero heat capacity of an ideal gas.

Why firms should not always maximize profits

OpenAIRE

Kolstad, Ivar

2006-01-01

Though corporate social responsibility (CSR) is on the agenda of most major corporations, corporate executives still largely support the view that corporations should maximize the returns to their owners. There are two lines of defence for this position. One is the Friedmanian view that maximizing owner returns is the corporate social responsibility of corporations. The other is a position voiced by many executives, that CSR and profits go together. This paper argues that the first position i...