Individualism and Collectivism in Trade Agents (extended abstract)

NARCIS (Netherlands)

Hofstede, G.J.; Jonker, C.M.; Verwaart, T.

2008-01-01

This paper was originally presented at IEA/AIE 2008 [1]. The current paper is an extended abstract for presentation at BNAIC 2008. Agent-Based Modeling can contribute to the understanding of international trade processes. Models for the effects of culture and cultural differences on agent behavior

A water market simulator considering pair-wise trades between agents

Science.gov (United States)

Huskova, I.; Erfani, T.; Harou, J. J.

2012-04-01

In many basins in England no further water abstraction licences are available. Trading water between water rights holders has been recognized as a potentially effective and economically efficient strategy to mitigate increasing scarcity. A screening tool that could assess the potential for trade through realistic simulation of individual water rights holders would help assess the solution's potential contribution to local water management. We propose an optimisation-driven water market simulator that predicts pair-wise trade in a catchment and represents its interaction with natural hydrology and engineered infrastructure. A model is used to emulate licence-holders' willingness to engage in short-term trade transactions. In their simplest form agents are represented using an economic benefit function. The working hypothesis is that trading behaviour can be partially predicted based on differences in marginal values of water over space and time and estimates of transaction costs on pair-wise trades. We discuss the further possibility of embedding rules, norms and preferences of the different water user sectors to more realistically represent the behaviours, motives and constraints of individual licence holders. The potential benefits and limitations of such a social simulation (agent-based) approach is contrasted with our simulator where agents are driven by economic optimization. A case study based on the Dove River Basin (UK) demonstrates model inputs and outputs. The ability of the model to suggest impacts of water rights policy reforms on trading is discussed.

Research of negotiation in network trade system based on multi-agent

Science.gov (United States)

Cai, Jun; Wang, Guozheng; Wu, Haiyan

2009-07-01

A construction and implementation technology of network trade based on multi-agent is described in this paper. First, we researched the technology of multi-agent, then we discussed the consumer's behaviors and the negotiation between purchaser and bargainer which emerges in the traditional business mode and analysed the key technology to implement the network trade system. Finally, we implement the system.

Trusted intermediating agents in electronic trade networks

NARCIS (Netherlands)

T.B. Klos (Tomas); F. Alkemade (Floortje)

2005-01-01

htmlabstract Electronic commerce and trading of information goods significantly impact the role of intermediaries: consumers can bypass intermediating agents by forming direct links to producers. One reason that traditional intermediaries can still make a profit, is that they have more knowledge of

A Cross-Cultural Multi-agent Model of Opportunism in Trade

Science.gov (United States)

Hofstede, Gert Jan; Jonker, Catholijn M.; Verwaart, Tim

According to transaction cost economics, contracts are always incomplete and offer opportunities to defect. Some level of trust is a sine qua non for trade. If the seller is better informed about product quality than the buyer, the buyer has to rely on information the seller provides or has to check the information by testing the product or tracing the supply chain processes, thus incurring extra transaction cost. An opportunistic seller who assumes the buyer to trust, may deliver a lower quality product than agreed upon. In human decisions to deceive and to show trust or distrust, issues like mutual expectations, shame, self-esteem, personality, and reputation are involved. These factors depend in part on traders' cultural background. This paper proposes an agent model of deceit and trust and describes a multi-agent simulation where trading agents are differentiated according to Hofstede's dimensions of national culture. Simulations of USA and Dutch trading situations are compared.

OntoTrader: An Ontological Web Trading Agent Approach for Environmental Information Retrieval

Directory of Open Access Journals (Sweden)

Luis Iribarne

2014-01-01

Full Text Available Modern Web-based Information Systems (WIS are becoming increasingly necessary to provide support for users who are in different places with different types of information, by facilitating their access to the information, decision making, workgroups, and so forth. Design of these systems requires the use of standardized methods and techniques that enable a common vocabulary to be defined to represent the underlying knowledge. Thus, mediation elements such as traders enrich the interoperability of web components in open distributed systems. These traders must operate with other third-party traders and/or agents in the system, which must also use a common vocabulary for communication between them. This paper presents the OntoTrader architecture, an Ontological Web Trading agent based on the OMG ODP trading standard. It also presents the ontology needed by some system agents to communicate with the trading agent and the behavioral framework for the SOLERES OntoTrader agent, an Environmental Management Information System (EMIS. This framework implements a “Query-Searching/Recovering-Response” information retrieval model using a trading service, SPARQL notation, and the JADE platform. The paper also presents reflection, delegation and, federation mediation models and describes formalization, an experimental testing environment in three scenarios, and a tool which allows our proposal to be evaluated and validated.

Agente adaptable y aprendizaje

Directory of Open Access Journals (Sweden)

Arturo Angel Lara Rivero

2013-05-01

Full Text Available En este trabajo se contrasta el concepto de agente programado con el de agente complejo adaptable, se presenta una nueva visión ligada al aprendizaje y la estructura del agente. La imagen del agente se analiza considerando los modelos internos, la práctica, el concepto de rutina y la influencia en su comportamiento, y la importancia del aprendizaje ex ante y ex post. Por último se muestra que la resolución de problemas está sujeta a restricciones del agente y se describen las formas de explorar el espacio de soluciones mediante tres tipos de exploración: exhaustiva, aleatoria y selectiva.

Applying Maxi-adjustment to Adaptive Information Filtering Agents

OpenAIRE

Lau, Raymond; ter Hofstede, Arthur H. M.; Bruza, Peter D.

2000-01-01

Learning and adaptation is a fundamental property of intelligent agents. In the context of adaptive information filtering, a filtering agent's beliefs about a user's information needs have to be revised regularly with reference to the user's most current information preferences. This learning and adaptation process is essential for maintaining the agent's filtering performance. The AGM belief revision paradigm provides a rigorous foundation for modelling rational and minimal changes to an age...

Adaptive hierarchical multi-agent organizations

NARCIS (Netherlands)

Ghijsen, M.; Jansweijer, W.N.H.; Wielinga, B.J.; Babuška, R.; Groen, F.C.A.

2010-01-01

In this chapter, we discuss the design of adaptive hierarchical organizations for multi-agent systems (MAS). Hierarchical organizations have a number of advantages such as their ability to handle complex problems and their scalability to large organizations. By introducing adaptivity in the

Trade in water and commodities as adaptations to global change

Science.gov (United States)

Lammers, R. B.; Hertel, T. W.; Prousevitch, A.; Baldos, U. L. C.; Frolking, S. E.; Liu, J.; Grogan, D. S.

2015-12-01

The human capacity for altering the water cycle has been well documented and given the expected change due to population, income growth, biofuels, climate, and associated land use change, there remains great uncertainty in both the degree of increased pressure on land and water resources and in our ability to adapt to these changes. Alleviating regional shortages in water supply can be carried out in a spatial hierarchy through i) direct trade of water between all regions, ii) development of infrastructure to improve water availability within regions (e.g. impounding rivers), iii) via inter-basin hydrological transfer between neighboring regions and, iv) via virtual water trade. These adaptation strategies can be managed via market trade in water and commodities to identify those strategies most likely to be adopted. This work combines the physically-based University of New Hampshire Water Balance Model (WBM) with the macro-scale Purdue University Simplified International Model of agricultural Prices Land use and the Environment (SIMPLE) to explore the interaction of supply and demand for fresh water globally. In this work we use a newly developed grid cell-based version of SIMPLE to achieve a more direct connection between the two modeling paradigms of physically-based models with optimization-driven approaches characteristic of economic models. We explore questions related to the global and regional impact of water scarcity and water surplus on the ability of regions to adapt to future change. Allowing for a variety of adaptation strategies such as direct trade of water and expanding the built water infrastructure, as well as indirect trade in commodities, will reduce overall global water stress and, in some regions, significantly reduce their vulnerability to these future changes.

Fault-Tolerant Consensus of Multi-Agent System With Distributed Adaptive Protocol.

Science.gov (United States)

Chen, Shun; Ho, Daniel W C; Li, Lulu; Liu, Ming

2015-10-01

In this paper, fault-tolerant consensus in multi-agent system using distributed adaptive protocol is investigated. Firstly, distributed adaptive online updating strategies for some parameters are proposed based on local information of the network structure. Then, under the online updating parameters, a distributed adaptive protocol is developed to compensate the fault effects and the uncertainty effects in the leaderless multi-agent system. Based on the local state information of neighboring agents, a distributed updating protocol gain is developed which leads to a fully distributed continuous adaptive fault-tolerant consensus protocol design for the leaderless multi-agent system. Furthermore, a distributed fault-tolerant leader-follower consensus protocol for multi-agent system is constructed by the proposed adaptive method. Finally, a simulation example is given to illustrate the effectiveness of the theoretical analysis.

Dynamic electronic institutions in agent oriented cloud robotic systems.

Science.gov (United States)

Nagrath, Vineet; Morel, Olivier; Malik, Aamir; Saad, Naufal; Meriaudeau, Fabrice

2015-01-01

The dot-com bubble bursted in the year 2000 followed by a swift movement towards resource virtualization and cloud computing business model. Cloud computing emerged not as new form of computing or network technology but a mere remoulding of existing technologies to suit a new business model. Cloud robotics is understood as adaptation of cloud computing ideas for robotic applications. Current efforts in cloud robotics stress upon developing robots that utilize computing and service infrastructure of the cloud, without debating on the underlying business model. HTM5 is an OMG's MDA based Meta-model for agent oriented development of cloud robotic systems. The trade-view of HTM5 promotes peer-to-peer trade amongst software agents. HTM5 agents represent various cloud entities and implement their business logic on cloud interactions. Trade in a peer-to-peer cloud robotic system is based on relationships and contracts amongst several agent subsets. Electronic Institutions are associations of heterogeneous intelligent agents which interact with each other following predefined norms. In Dynamic Electronic Institutions, the process of formation, reformation and dissolution of institutions is automated leading to run time adaptations in groups of agents. DEIs in agent oriented cloud robotic ecosystems bring order and group intellect. This article presents DEI implementations through HTM5 methodology.

Adapting Price Predictions in TAC SCM

Science.gov (United States)

Pardoe, David; Stone, Peter

In agent-based markets, adapting to the behavior of other agents is often necessary for success. When it is not possible to directly model individual competitors, an agent may instead model and adapt to the market conditions that result from competitor behavior. Such an agent could still benefit from reasoning about specific competitor strategies by considering how various combinations of these strategies would impact the conditions being modeled. We present an application of such an approach to a specific prediction problem faced by the agent TacTex-06 in the Trading Agent Competition's Supply Chain Management scenario (TAC SCM).

Connection adaption for control of networked mobile chaotic agents.

Science.gov (United States)

Zhou, Jie; Zou, Yong; Guan, Shuguang; Liu, Zonghua; Xiao, Gaoxi; Boccaletti, S

2017-11-22

In this paper, we propose a strategy for the control of mobile chaotic oscillators by adaptively rewiring connections between nearby agents with local information. In contrast to the dominant adaptive control schemes where coupling strength is adjusted continuously according to the states of the oscillators, our method does not request adaption of coupling strength. As the resulting interaction structure generated by this proposed strategy is strongly related to unidirectional chains, by investigating synchronization property of unidirectional chains, we reveal that there exists a certain coupling range in which the agents could be controlled regardless of the length of the chain. This feature enables the adaptive strategy to control the mobile oscillators regardless of their moving speed. Compared with existing adaptive control strategies for networked mobile agents, our proposed strategy is simpler for implementation where the resulting interaction networks are kept unweighted at all time.

Smart swarms of bacteria-inspired agents with performance adaptable interactions.

Directory of Open Access Journals (Sweden)

Adi Shklarsh

2011-09-01

Full Text Available Collective navigation and swarming have been studied in animal groups, such as fish schools, bird flocks, bacteria, and slime molds. Computer modeling has shown that collective behavior of simple agents can result from simple interactions between the agents, which include short range repulsion, intermediate range alignment, and long range attraction. Here we study collective navigation of bacteria-inspired smart agents in complex terrains, with adaptive interactions that depend on performance. More specifically, each agent adjusts its interactions with the other agents according to its local environment--by decreasing the peers' influence while navigating in a beneficial direction, and increasing it otherwise. We show that inclusion of such performance dependent adaptable interactions significantly improves the collective swarming performance, leading to highly efficient navigation, especially in complex terrains. Notably, to afford such adaptable interactions, each modeled agent requires only simple computational capabilities with short-term memory, which can easily be implemented in simple swarming robots.

Smart swarms of bacteria-inspired agents with performance adaptable interactions.

Science.gov (United States)

Shklarsh, Adi; Ariel, Gil; Schneidman, Elad; Ben-Jacob, Eshel

2011-09-01

Collective navigation and swarming have been studied in animal groups, such as fish schools, bird flocks, bacteria, and slime molds. Computer modeling has shown that collective behavior of simple agents can result from simple interactions between the agents, which include short range repulsion, intermediate range alignment, and long range attraction. Here we study collective navigation of bacteria-inspired smart agents in complex terrains, with adaptive interactions that depend on performance. More specifically, each agent adjusts its interactions with the other agents according to its local environment--by decreasing the peers' influence while navigating in a beneficial direction, and increasing it otherwise. We show that inclusion of such performance dependent adaptable interactions significantly improves the collective swarming performance, leading to highly efficient navigation, especially in complex terrains. Notably, to afford such adaptable interactions, each modeled agent requires only simple computational capabilities with short-term memory, which can easily be implemented in simple swarming robots.

Agent-based model with asymmetric trading and herding for complex financial systems.

Science.gov (United States)

Chen, Jun-Jie; Zheng, Bo; Tan, Lei

2013-01-01

For complex financial systems, the negative and positive return-volatility correlations, i.e., the so-called leverage and anti-leverage effects, are particularly important for the understanding of the price dynamics. However, the microscopic origination of the leverage and anti-leverage effects is still not understood, and how to produce these effects in agent-based modeling remains open. On the other hand, in constructing microscopic models, it is a promising conception to determine model parameters from empirical data rather than from statistical fitting of the results. To study the microscopic origination of the return-volatility correlation in financial systems, we take into account the individual and collective behaviors of investors in real markets, and construct an agent-based model. The agents are linked with each other and trade in groups, and particularly, two novel microscopic mechanisms, i.e., investors' asymmetric trading and herding in bull and bear markets, are introduced. Further, we propose effective methods to determine the key parameters in our model from historical market data. With the model parameters determined for six representative stock-market indices in the world, respectively, we obtain the corresponding leverage or anti-leverage effect from the simulation, and the effect is in agreement with the empirical one on amplitude and duration. At the same time, our model produces other features of the real markets, such as the fat-tail distribution of returns and the long-term correlation of volatilities. We reveal that for the leverage and anti-leverage effects, both the investors' asymmetric trading and herding are essential generation mechanisms. Among the six markets, however, the investors' trading is approximately symmetric for the five markets which exhibit the leverage effect, thus contributing very little. These two microscopic mechanisms and the methods for the determination of the key parameters can be applied to other complex

Is It Possible To Use Intelligent Systems To Design A Profitable Foreign Exchange Trading Agent?

OpenAIRE

Julian, Pomfret-Pudelsky

2009-01-01

In this paper, a trading agent is developed using a basket of intelligent systems with the goal of trading the GBPUSD currency pair profitably in the Foreign Exchange market. The basket of intelligent system consists of two regression models: a radial basis neural network and a TSK-fuzzy inference system; and three classification models: k-nearest neighbour, support vector machine and a decision tree. The trading strategy combines the predictions of each model using a Kalman-type filter to...

An innovative cross-sectoral method for implementation of trade-off adaptation strategy assessment under climate change

Science.gov (United States)

Tsao, Jung-Hsuan; Tung, Ching-Pin; Liu, Tzu-Ming

2014-05-01

Climate change will increase sharp risks to the water and food supply in coming decades. Although impact assessment and adaptation evaluation has been discussed a lot in recent years, the importance of adaptation implement should not be ignored. In Taiwan, and elsewhere, fallow is an option of adaptation strategy under climate change. Fallow would improve the water scarcity of domestic use, but the food security might be threatened. The trade-off effects of adaptation actions are just like the side effects of medicine which cannot be avoided. Thus, managing water resources with an integrated approach will be urgent. This study aims to establish a cross-sectoral framework for implementation the trade-off adaptation strategy. Not only fallow, but also other trade-off strategy like increasing the percentage of national grain self-sufficiency would be analyzed by a rational decision process. The recent percentage of grain self-sufficiency in Taiwan is around 32, which was decreasing from 53 thirty years ago. Yet, the goal of increasing grain self-sufficiency means much more water must be used in agriculture. In that way, domestic users may face the water shortage situation. Considering the conflicts between water supply and food security, the concepts from integrative negotiation are appropriate to apply. The implementation of trade-off adaptation strategies needs to start by quantifying the utility of water supply and food security were be quantified. Next, each side's bottom line can be found by BATNA (Best Alternative to a Negotiated Agreement) and ZOPA (Zone of Possible Agreement). ZOPA provides the entire possible outcomes, and BATNA ensures the efficiency of adaptation actions by moving along with Pareto frontier. Therefore, the optimal percentage of fallow and grain self-sufficiency can be determined. Furthermore, BATNA also provides the pathway step by step which can be a guideline of adaptation strategies. This framework allows analysts and stakeholder to

Agent-based model with asymmetric trading and herding for complex financial systems.

Directory of Open Access Journals (Sweden)

Jun-Jie Chen

Full Text Available BACKGROUND: For complex financial systems, the negative and positive return-volatility correlations, i.e., the so-called leverage and anti-leverage effects, are particularly important for the understanding of the price dynamics. However, the microscopic origination of the leverage and anti-leverage effects is still not understood, and how to produce these effects in agent-based modeling remains open. On the other hand, in constructing microscopic models, it is a promising conception to determine model parameters from empirical data rather than from statistical fitting of the results. METHODS: To study the microscopic origination of the return-volatility correlation in financial systems, we take into account the individual and collective behaviors of investors in real markets, and construct an agent-based model. The agents are linked with each other and trade in groups, and particularly, two novel microscopic mechanisms, i.e., investors' asymmetric trading and herding in bull and bear markets, are introduced. Further, we propose effective methods to determine the key parameters in our model from historical market data. RESULTS: With the model parameters determined for six representative stock-market indices in the world, respectively, we obtain the corresponding leverage or anti-leverage effect from the simulation, and the effect is in agreement with the empirical one on amplitude and duration. At the same time, our model produces other features of the real markets, such as the fat-tail distribution of returns and the long-term correlation of volatilities. CONCLUSIONS: We reveal that for the leverage and anti-leverage effects, both the investors' asymmetric trading and herding are essential generation mechanisms. Among the six markets, however, the investors' trading is approximately symmetric for the five markets which exhibit the leverage effect, thus contributing very little. These two microscopic mechanisms and the methods for the

Adaptive Synchronization for Heterogeneous Multi-Agent Systems with Switching Topologies

Directory of Open Access Journals (Sweden)

Muhammad Ridho Rosa

2018-02-01

Full Text Available This work provides a multi-agent extension of output-feedback model reference adaptive control (MRAC, designed to synchronize a network of heterogeneous uncertain agents. The implementation of this scheme is based on multi-agent matching conditions. The practical advantage of the proposed MRAC is the possibility of handling the case of the unknown dynamics of the agents only by using the output and the control input of its neighbors. In addition, it is reasonable to consider the case when the communication topology is time-varying. In this work, the time-varying communication leads to a switching control structure that depends on the number of the predecessor of the agents. By using the switching control structure to handle the time-varying topologies, we show that synchronization can be achieved. The multi-agent adaptive switching controller is first analyzed, and numerical simulations based on formation control of simplifier quadcopter dynamics are provided.

The highly intelligent virtual agents for modeling financial markets

Science.gov (United States)

Yang, G.; Chen, Y.; Huang, J. P.

2016-02-01

Researchers have borrowed many theories from statistical physics, like ensemble, Ising model, etc., to study complex adaptive systems through agent-based modeling. However, one fundamental difference between entities (such as spins) in physics and micro-units in complex adaptive systems is that the latter are usually with high intelligence, such as investors in financial markets. Although highly intelligent virtual agents are essential for agent-based modeling to play a full role in the study of complex adaptive systems, how to create such agents is still an open question. Hence, we propose three principles for designing high artificial intelligence in financial markets and then build a specific class of agents called iAgents based on these three principles. Finally, we evaluate the intelligence of iAgents through virtual index trading in two different stock markets. For comparison, we also include three other types of agents in this contest, namely, random traders, agents from the wealth game (modified on the famous minority game), and agents from an upgraded wealth game. As a result, iAgents perform the best, which gives a well support for the three principles. This work offers a general framework for the further development of agent-based modeling for various kinds of complex adaptive systems.

Carbon emissions trading scheme exploration in China: A multi-agent-based model

International Nuclear Information System (INIS)

Tang, Ling; Wu, Jiaqian; Yu, Lean; Bao, Qin

2015-01-01

To develop a low-carbon economy, China launched seven pilot programs for carbon emissions trading (CET) in 2011 and plans to establish a nationwide CET mechanism in 2015. This paper formulated a multi-agent-based model to investigate the impacts of different CET designs in order to find the most appropriate one for China. The proposed bottom-up model includes all main economic agents in a general equilibrium framework. The simulation results indicate that (1) CET would effectively reduce carbon emissions, with a certain negative impact on the economy, (2) as for allowance allocation, the grandfathering rule is relatively moderate, while the benchmarking rule is more aggressive, (3) as for the carbon price, when the price level in the secondary CET market is regulated to be around RMB 40 per metric ton, a satisfactory emission mitigation effect can be obtained, (4) the penalty rate is suggested to be carefully designed to balance the economy development and mitigation effect, and (5) subsidy policy for energy technology improvement can effectively reduce carbon emissions without an additional negative impact on the economy. The results also indicate that the proposed novel model is a promising tool for CET policy making and analyses. -- Highlights: •A multi-agent-based model is proposed for carbon emissions trading (CET) in China. •Three agents are included: government, firms in different sectors and households. •The impacts of CET on the economy and environment in China are analyzed. •Different CET designs are simulated to find an appropriate policy for China. •Results confirm the effectiveness of the model and give helpful insights into CET design

Carbon allowance auction design of China's emissions trading scheme: A multi-agent-based approach

International Nuclear Information System (INIS)

Tang, Ling; Wu, Jiaqian; Yu, Lean; Bao, Qin

2017-01-01

In this paper, a multi-agent-based ETS simulation model is proposed for carbon allowance auction design in China. In the proposed model, two main agents, i.e., the government (the ETS implementer) and the firms in different sectors (the ETS targets), are considered. Under the ETS policy, all agents make various decisions individually according to their own goals, and interact with each other through three main markets: the commodity market, the primary carbon auction market and the secondary carbon trading market. Different popular auction designs are introduced into the ETS formulation to offer helpful insights into China's ETS design. (1) Generally, the ETS would lead to positive effects on China's carbon mitigation and energy structure improvement, but a negative impact on economy. (2) As for auction forms, the uniform-price design is relatively moderate, while the discriminative-price design is quite aggressive in both economic damage and emissions reduction. (3) As for carbon price, the uniform-price auction might generate a slightly higher market clearing price than the discriminative-price auction, and the prices under two auction rules fluctuate about RMB 40 per metric ton. (4) As for carbon cap, the total allowances in the carbon auction market should be carefully set to well balance economic growth and mitigation effect. - Highlights: • A multi-agent-based model is proposed for China's emissions trading scheme (ETS). • Two main economic agents are included: government and firms in different sectors. • Auction-based allocation for initial carbon allowances is especially investigated. • Economic and environmental impacts of different auction designs are analyzed. • Results confirm the validity of the model and give helpful insights into ETS design.

Spiders in Motion: Demonstrating Adaptation, Structure-Function Relationships, and Trade-Offs in Invertebrates

Science.gov (United States)

Bowlin, Melissa S.; McLeer, Dorothy F.; Danielson-Francois, Anne M.

2014-01-01

Evolutionary history and structural considerations constrain all aspects of animal physiology. Constraints on invertebrate locomotion are especially straightforward for students to observe and understand. In this exercise, students use spiders to investigate the concepts of adaptation, structure-function relationships, and trade-offs. Students…

Agente adaptable, aprendizaje y estructura del ambiente: un enfoque alternativo

Directory of Open Access Journals (Sweden)

Arturo Lara Rivero

2012-06-01

Full Text Available En este trabajo se contrasta el concepto de agente programado con el de agente complejo adaptable, se presenta una nueva visión ligada al aprendizaje y la estructura del agente. La imagen del agente se analiza considerando los modelos internos, la práctica, el concepto de rutina y la influencia en su comportamiento, y la importancia del aprendizaje ex ante y ex post. Por último se muestra que la resolución de problemas está sujeta a restricciones del agente y se describen las formas de explorar el espacio de soluciones mediante tres tipos de exploración: exhaustiva, aleatoria y selectiva.

Adaptation gap hypothesis: How differences between users’ expected and perceived agent functions affect their subjective impression

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Takanori Komatsu

2011-02-01

Full Text Available We describe an “adaptation gap” that indicates the differences between the functions of artificial agents that users expect before starting their interactions and the functions they perceive after their interactions. We investigated the effect of this adaptation gap on users’ impressions of artificial agents because any variations in impression before and after the start of an interaction determines whether the user feels that this agent is worth interacting with. The results showed that positive or negative signs of the adaptation gap and subjective impression scores of agents before the experiment significantly affected the users’ final impressions of the agents.

Analyzing Katana referral hospital as a complex adaptive system: agents, interactions and adaptation to a changing environment.

Science.gov (United States)

Karemere, Hermès; Ribesse, Nathalie; Marchal, Bruno; Macq, Jean

2015-01-01

This study deals with the adaptation of Katana referral hospital in Eastern Democratic Republic of Congo in a changing environment that is affected for more than a decade by intermittent armed conflicts. His objective is to generate theoretical proposals for addressing differently the analysis of hospitals governance in the aims to assess their performance and how to improve that performance. The methodology applied approach uses a case study using mixed methods ( qualitative and quantitative) for data collection. It uses (1) hospital data to measure the output of hospitals, (2) literature review to identify among others, events and interventions recorded in the history of hospital during the study period and (3) information from individual interviews to validate the interpretation of the results of the previous two sources of data and understand the responsiveness of management team referral hospital during times of change. The study brings four theoretical propositions: (1) Interaction between key agents is a positive force driving adaptation if the actors share a same vision, (2) The strength of the interaction between agents is largely based on the nature of institutional arrangements, which in turn are shaped by the actors themselves, (3) The owner and the management team play a decisive role in the implementation of effective institutional arrangements and establishment of positive interactions between agents, (4) The analysis of recipient population's perception of health services provided allow to better tailor and adapt the health services offer to the population's needs and expectations. Research shows that it isn't enough just to provide support (financial and technical), to manage a hospital for operate and adapt to a changing environment but must still animate, considering that it is a complex adaptive system and that this animation is nothing other than the induction of a positive interaction between agents.

Impact of Carbon Quota Allocation Mechanism on Emissions Trading: An Agent-Based Simulation

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Wei Jiang

2016-08-01

Full Text Available This paper establishes an agent-based simulation system of the carbon emissions trading in accordance with the complex feature of the trading process. This system analyzes the impact of the carbon quota allocation mechanism on emissions trading for three different aspects including the amount of emissions reduction, the economic effect on the emitters, and the emissions reduction cost. Based on the data of the carbon emissions of different industries in China, several simulations were made. The results indicate that the emissions trading policy can effectively reduce carbon emissions in a perfectly competitive market. Moreover, by comparing separate quota allocation mechanisms, we obtain the result that the scheme with a small extent quota decrease in a comprehensive allocation mechanism can minimize the unit carbon emission cost. Implementing this scheme can also achieve minimal effects of carbon emissions limitation on the economy on the basis that the environment is not destroyed. However, excessive quota decrease cannot promote the emitters to reduce emission. Taking into account that several developing countries have the dual task of limiting carbon emissions and developing the economy, it is necessary to adopt a comprehensive allocation mechanism of the carbon quota and increase the initial proportion of free allocation.

Agent Based Framework Architecture for Supporting Content Adaptation for Mobile Government

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Hasan Omar Al-Sakran

2013-01-01

Full Text Available Rapid spread of smart mobile technology that supports internet access is transforming the way governments provide services to their citizens. Mobile devices have different capabilities based on the manufacturers and models. This paper proposes a new framework for adapting the content of M-government services using mobile agent technology. The framework is based on a mediation architecture that uses multiple mobile agents and XML as semi-structure mediation language. The flexibility of the mediation and XML provide an adaptive environment to stream data based on the capabilities of the device sending the query to the system.

Loss Aversion, Adaptive Beliefs, and Asset Pricing Dynamics

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Kamal Samy Selim

2015-01-01

Full Text Available We study asset pricing dynamics in artificial financial markets model. The financial market is populated with agents following two heterogeneous trading beliefs, the technical and the fundamental prediction rules. Agents switch between trading rules with respect to their past performance. The agents are loss averse over asset price fluctuations. Loss aversion behaviour depends on the past performance of the trading strategies in terms of an evolutionary fitness measure. We propose a novel application of the prospect theory to agent-based modelling, and by simulation, the effect of evolutionary fitness measure on adaptive belief system is investigated. For comparison, we study pricing dynamics of a financial market populated with chartists perceive losses and gains symmetrically. One of our contributions is validating the agent-based models using real financial data of the Egyptian Stock Exchange. We find that our framework can explain important stylized facts in financial time series, such as random walk price behaviour, bubbles and crashes, fat-tailed return distributions, power-law tails in the distribution of returns, excess volatility, volatility clustering, the absence of autocorrelation in raw returns, and the power-law autocorrelations in absolute returns. In addition to this, we find that loss aversion improves market quality and market stability.

Thermotolerant Yeast Strains Adapted by Laboratory Evolution Show Trade-Off at Ancestral Temperatures and Preadaptation to Other Stresses

DEFF Research Database (Denmark)

Caspeta, Luis; Nielsen, Jens

2015-01-01

adaptive laboratory evolution, we previously isolated seven Saccharomyces cerevisiae strains with improved growth at 40°C. Here, we show that genetic adaptations to high temperature caused a growth trade-off at ancestral temperatures, reduced cellular functions, and improved tolerance of other stresses...... in the ancestral strain. The latter is an advantageous attribute for acquiring thermotolerance and correlates with the reduction of yeast functions associated with loss of respiration capacity. This trait caused glycerol overproduction that was associated with the growth trade-off at ancestral temperatures....... In combination with altered sterol composition of cellular membranes, glycerol overproduction was also associated with yeast osmotolerance and improved tolerance of high concentrations of glucose and ethanol. Our study shows that thermal adaptation of yeast is suitable for improving yeast resistance...

Adaptive Multi-Agent Systems for Constrained Optimization

Science.gov (United States)

Macready, William; Bieniawski, Stefan; Wolpert, David H.

2004-01-01

Product Distribution (PD) theory is a new framework for analyzing and controlling distributed systems. Here we demonstrate its use for distributed stochastic optimization. First we review one motivation of PD theory, as the information-theoretic extension of conventional full-rationality game theory to the case of bounded rational agents. In this extension the equilibrium of the game is the optimizer of a Lagrangian of the (probability distribution of) the joint state of the agents. When the game in question is a team game with constraints, that equilibrium optimizes the expected value of the team game utility, subject to those constraints. The updating of the Lagrange parameters in the Lagrangian can be viewed as a form of automated annealing, that focuses the MAS more and more on the optimal pure strategy. This provides a simple way to map the solution of any constrained optimization problem onto the equilibrium of a Multi-Agent System (MAS). We present computer experiments involving both the Queen s problem and K-SAT validating the predictions of PD theory and its use for off-the-shelf distributed adaptive optimization.

A New Multi-Agent Approach to Adaptive E-Education

Science.gov (United States)

Chen, Jing; Cheng, Peng

Improving customer satisfaction degree is important in e-Education. This paper describes a new approach to adaptive e-Education taking into account the full spectrum of Web service techniques and activities. It presents a multi-agents architecture based on artificial psychology techniques, which makes the e-Education process both adaptable and dynamic, and hence up-to-date. Knowledge base techniques are used to support the e-Education process, and artificial psychology techniques to deal with user psychology, which makes the e-Education system more effective and satisfying.

An adaptive response to alkylating agents in Aspergillus nidulans.

Science.gov (United States)

Hooley, P; Shawcross, S G; Strike, P

1988-11-01

A simple method is described for demonstrating adaptation to alkylation damage in Aspergillus nidulans. One wild type, two MNNG-sensitive, and one MNNG-resistant strain all showed improvement in colony growth when challenged with MNNG following appropriate inducing pretreatments. Other alkylating agents (MMS, EMS) could also adapt mycelium to later MNNG challenge, while 4NQO and UV could not. The inducible effect was not transmissible through conidia. A standard reversion assay based upon methG proved impractical for studying mutation frequencies during alkylation treatments owing to variations in MNNG resistance amongst revertants.

Asset Prices and Trading Volume under Fixed Transactions Costs.

Science.gov (United States)

Lo, Andrew W.; Mamaysky, Harry; Wang, Jiang

2004-01-01

We propose a dynamic equilibrium model of asset prices and trading volume when agents face fixed transactions costs. We show that even small fixed costs can give rise to large "no-trade" regions for each agent's optimal trading policy. The inability to trade more frequently reduces the agents' asset demand and in equilibrium gives rise to a…

Market mood, adaptive beliefs and asset price dynamics

International Nuclear Information System (INIS)

Dieci, Roberto; Foroni, Ilaria; Gardini, Laura; He Xuezhong

2006-01-01

Empirical evidence has suggested that, facing different trading strategies and complicated decision, the proportions of agents relying on particular strategies may stay at constant level or vary over time. This paper presents a simple 'dynamic market fraction' model of two groups of traders, fundamentalists and trend followers, under a market maker scenario. Market mood and evolutionary adaption are characterized by fixed and adaptive switching fraction among two groups, respectively. Using local stability and bifurcation analysis, as well as numerical simulation, the role played by the key parameters in the market behaviour is examined. Particular attention is paid to the impact of the market fraction, determined by the fixed proportions of confident fundamentalists and trend followers, and by the proportion of adaptively rational agents, who adopt different strategies over time depending on realized profits

Intermediation in Foreign Trade: When do Exporters Rely on Intermediaries?

DEFF Research Database (Denmark)

Schröder, Philipp J.H.; Trabold, H.; Trübswetter, P.

2005-01-01

The paper explores the question of why trade intermediaries (TIs) are frequently used as agents for exports to some countries but not to others. First, we adapt a standard intra-industry trade model with variable export costs (e.g. transport) and fixed export costs (e.g. market access) to include...... a TI that is able to pool market access cost. This framework suggests explanatory factors for the TI share in a country's exports, which are largely in line with the literature. Second, we test these explanatory factors with a new data set based on French customs information. The paper finds that: (i......) higher market access costs increase the TI share, (ii) smaller export markets feature a larger TI share, (iii) network effects are important determinants of trade intermediation....

Biological trade and markets.

Science.gov (United States)

Hammerstein, Peter; Noë, Ronald

2016-02-05

Cooperation between organisms can often be understood, like trade between merchants, as a mutually beneficial exchange of services, resources or other 'commodities'. Mutual benefits alone, however, are not sufficient to explain the evolution of trade-based cooperation. First, organisms may reject a particular trade if another partner offers a better deal. Second, while human trade often entails binding contracts, non-human trade requires unwritten 'terms of contract' that 'self-stabilize' trade and prevent cheating even if all traders strive to maximize fitness. Whenever trading partners can be chosen, market-like situations arise in nature that biologists studying cooperation need to account for. The mere possibility of exerting partner choice stabilizes many forms of otherwise cheatable trade, induces competition, facilitates the evolution of specialization and often leads to intricate forms of cooperation. We discuss selected examples to illustrate these general points and review basic conceptual approaches that are important in the theory of biological trade and markets. Comparing these approaches with theory in economics, it turns out that conventional models-often called 'Walrasian' markets-are of limited relevance to biology. In contrast, early approaches to trade and markets, as found in the works of Ricardo and Cournot, contain elements of thought that have inspired useful models in biology. For example, the concept of comparative advantage has biological applications in trade, signalling and ecological competition. We also see convergence between post-Walrasian economics and biological markets. For example, both economists and biologists are studying 'principal-agent' problems with principals offering jobs to agents without being sure that the agents will do a proper job. Finally, we show that mating markets have many peculiarities not shared with conventional economic markets. Ideas from economics are useful for biologists studying cooperation but need

FRIEND: a brain-monitoring agent for adaptive and assistive systems.

Science.gov (United States)

Morris, Alexis; Ulieru, Mihaela

2012-01-01

This paper presents an architectural design for adaptive-systems agents (FRIEND) that use brain state information to make more effective decisions on behalf of a user; measuring brain context versus situational demands. These systems could be useful for alerting users to cognitive workload levels or fatigue, and could attempt to compensate for higher cognitive activity by filtering noise information. In some cases such systems could also share control of devices, such as pulling over in an automated vehicle. These aim to assist people in everyday systems to perform tasks better and be more aware of internal states. Achieving a functioning system of this sort is a challenge, involving a unification of brain- computer-interfaces, human-computer-interaction, soft-computin deliberative multi-agent systems disciplines. Until recently, these were not able to be combined into a usable platform due largely to technological limitations (e.g., size, cost, and processing speed), insufficient research on extracting behavioral states from EEG signals, and lack of low-cost wireless sensing headsets. We aim to surpass these limitations and develop control architectures for making sense of brain state in applications by realizing an agent architecture for adaptive (human-aware) technology. In this paper we present an early, high-level design towards implementing a multi-purpose brain-monitoring agent system to improve user quality of life through the assistive applications of psycho-physiological monitoring, noise-filtering, and shared system control.

Integrating adaptive behaviour in large-scale flood risk assessments: an Agent-Based Modelling approach

Science.gov (United States)

Haer, Toon; Aerts, Jeroen

2015-04-01

Between 1998 and 2009, Europe suffered over 213 major damaging floods, causing 1126 deaths, displacing around half a million people. In this period, floods caused at least 52 billion euro in insured economic losses making floods the most costly natural hazard faced in Europe. In many low-lying areas, the main strategy to cope with floods is to reduce the risk of the hazard through flood defence structures, like dikes and levees. However, it is suggested that part of the responsibility for flood protection needs to shift to households and businesses in areas at risk, and that governments and insurers can effectively stimulate the implementation of individual protective measures. However, adaptive behaviour towards flood risk reduction and the interaction between the government, insurers, and individuals has hardly been studied in large-scale flood risk assessments. In this study, an European Agent-Based Model is developed including agent representatives for the administrative stakeholders of European Member states, insurers and reinsurers markets, and individuals following complex behaviour models. The Agent-Based Modelling approach allows for an in-depth analysis of the interaction between heterogeneous autonomous agents and the resulting (non-)adaptive behaviour. Existing flood damage models are part of the European Agent-Based Model to allow for a dynamic response of both the agents and the environment to changing flood risk and protective efforts. By following an Agent-Based Modelling approach this study is a first contribution to overcome the limitations of traditional large-scale flood risk models in which the influence of individual adaptive behaviour towards flood risk reduction is often lacking.

Incentivising flood risk adaptation through risk based insurance premiums : Trade-offs between affordability and risk reduction

NARCIS (Netherlands)

Hudson, Paul F.; Botzen, W.J.W.; Feyen, L.; Aerts, Jeroen C.J.H.

2016-01-01

The financial incentives offered by the risk-based pricing of insurance can stimulate policyholder adaptation to flood risk while potentially conflicting with affordability. We examine the trade-off between risk reduction and affordability in a model of public-private flood insurance in France and

Incentivising flood risk adaptation through ris based insurance premiums: trade-offs between affordability and risk reduction

NARCIS (Netherlands)

Hudson, P.G.M.B.; Botzen, W.J.W.; Feyen, L.; Aerts, J.C.J.H.

2016-01-01

The financial incentives offered by the risk-based pricing of insurance can stimulate policyholder adaptation to flood risk while potentially conflicting with affordability. We examine the trade-off between risk reduction and affordability in a model of public-private flood insurance in France and

Adaptive trade-offs in juvenile salmonid metabolism associated with habitat partitioning between coho salmon and steelhead trout in coastal streams.

Science.gov (United States)

Van Leeuwen, Travis E; Rosenfeld, Jordan S; Richards, Jeffrey G

2011-09-01

1. Adaptive trade-offs are fundamental to the evolution of diversity and the coexistence of similar taxa and occur when complimentary combinations of traits maximize efficiency of resource exploitation or survival at different points on environmental gradients. 2. Standard metabolic rate (SMR) is a key physiological trait that reflects adaptations to baseline metabolic performance, whereas active metabolism reflects adaptations to variable metabolic output associated with performance related to foraging, predator avoidance, aggressive interactions or migratory movements. Benefits of high SMR and active metabolism may change along a resource (productivity) gradient, indicating that a trade-off exists among active metabolism, resting metabolism and energy intake. 3. We measured and compared SMR, maximal metabolic rate (MMR), aerobic scope (AS), swim performance (UCrit) and growth of juvenile hatchery and wild steelhead and coho salmon held on high- and low-food rations in order to better understand the potential significance of variation in SMR to growth, differentiation between species, and patterns of habitat use along a productivity gradient. 4. We found that differences in SMR, MMR, AS, swim performance and growth rate between steelhead trout and coho salmon were reduced in hatchery-reared fish compared with wild fish. Wild steelhead had a higher MMR, AS, swim performance and growth rate than wild coho, but adaptations between species do not appear to involve differences in SMR or to trade-off increased growth rate against lower swim performance, as commonly observed for high-growth strains. Instead, we hypothesize that wild steelhead may be trading off higher growth rate for lower food consumption efficiency, similar to strategies adopted by anadromous vs. resident brook trout and Atlantic salmon vs. brook trout. This highlights potential differences in food consumption and digestion strategies as cryptic adaptations ecologically differentiating salmonid species

Cooperative control of multi-agent systems optimal and adaptive design approaches

CERN Document Server

Lewis, Frank L; Hengster-Movric, Kristian; Das, Abhijit

2014-01-01

Task complexity, communication constraints, flexibility and energy-saving concerns are all factors that may require a group of autonomous agents to work together in a cooperative manner. Applications involving such complications include mobile robots, wireless sensor networks, unmanned aerial vehicles (UAVs), spacecraft, and so on. In such networked multi-agent scenarios, the restrictions imposed by the communication graph topology can pose severe problems in the design of cooperative feedback control systems.  Cooperative control of multi-agent systems is a challenging topic for both control theorists and practitioners and has been the subject of significant recent research. Cooperative Control of Multi-Agent Systems extends optimal control and adaptive control design methods to multi-agent systems on communication graphs.  It develops Riccati design techniques for general linear dynamics for cooperative state feedback design, cooperative observer design, and cooperative dynamic output feedback design.  B...

Distributed robust adaptive control of high order nonlinear multi agent systems.

Science.gov (United States)

Hashemi, Mahnaz; Shahgholian, Ghazanfar

2018-03-01

In this paper, a robust adaptive neural network based controller is presented for multi agent high order nonlinear systems with unknown nonlinear functions, unknown control gains and unknown actuator failures. At first, Neural Network (NN) is used to approximate the nonlinear uncertainty terms derived from the controller design procedure for the followers. Then, a novel distributed robust adaptive controller is developed by combining the backstepping method and the Dynamic Surface Control (DSC) approach. The proposed controllers are distributed in the sense that the designed controller for each follower agent only requires relative state information between itself and its neighbors. By using the Young's inequality, only few parameters need to be tuned regardless of NN nodes number. Accordingly, the problems of dimensionality curse and explosion of complexity are counteracted, simultaneously. New adaptive laws are designed by choosing the appropriate Lyapunov-Krasovskii functionals. The proposed approach proves the boundedness of all the closed-loop signals in addition to the convergence of the distributed tracking errors to a small neighborhood of the origin. Simulation results indicate that the proposed controller is effective and robust. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

Trade Services System Adaptation for Sustainable Development

Science.gov (United States)

Khrichenkov, A.; Shaufler, V.; Bannikova, L.

2017-11-01

Under market conditions, the trade services system in post-Soviet Russia, being one of the most important city infrastructures, loses its systematic and hierarchic consistency hence provoking the degradation of communicating transport systems and urban planning framework. This article describes the results of the research carried out to identify objects and object parameters that influence functioning of a locally significant trade services system. Based on the revealed consumer behaviour patterns, we propose methods to determine the optimal parameters of objects inside a locally significant trade services system.

Intermediation in Foreign Trade: When do Exporters Rely on Intermediaries?

DEFF Research Database (Denmark)

Schröder, Philipp; Trabold, Harald; Trübswetter, Parvati

2003-01-01

The paper explores theoretically and empirically why trade intermediaries (TIs) are frequently used as agents for exports to some countries but not to others. We adapt a standard intra-industry trade model with variable export costs (e.g. transport) and fixed export costs (e.g. market access......) to include a TI that is able to pool market access cost. From this framework explanatory factors for the TI share in a country's exports are derived and subsequently tested with a new data set based on French customs information. The paper finds that: (i) higher market access costs increase the TI share, (ii......) smaller export markets feature a larger TI share, (iii) the TI share is independent from variable (distance-dependent) export costs....

Adaptive architectures for resilient control of networked multiagent systems in the presence of misbehaving agents

Science.gov (United States)

Torre, Gerardo De La; Yucelen, Tansel

2018-03-01

Control algorithms of networked multiagent systems are generally computed distributively without having a centralised entity monitoring the activity of agents; and therefore, unforeseen adverse conditions such as uncertainties or attacks to the communication network and/or failure of agent-wise components can easily result in system instability and prohibit the accomplishment of system-level objectives. In this paper, we study resilient coordination of networked multiagent systems in the presence of misbehaving agents, i.e. agents that are subject to exogenous disturbances that represent a class of adverse conditions. In particular, a distributed adaptive control architecture is presented for directed and time-varying graph topologies to retrieve a desired networked multiagent system behaviour. Apart from the existing relevant literature that make specific assumptions on the graph topology and/or the fraction of misbehaving agents, we show that the considered class of adverse conditions can be mitigated by the proposed adaptive control approach that utilises a local state emulator - even if all agents are misbehaving. Illustrative numerical examples are provided to demonstrate the theoretical findings.

Adaptive, Distributed Control of Constrained Multi-Agent Systems

Science.gov (United States)

Bieniawski, Stefan; Wolpert, David H.

2004-01-01

Product Distribution (PO) theory was recently developed as a broad framework for analyzing and optimizing distributed systems. Here we demonstrate its use for adaptive distributed control of Multi-Agent Systems (MASS), i.e., for distributed stochastic optimization using MAS s. First we review one motivation of PD theory, as the information-theoretic extension of conventional full-rationality game theory to the case of bounded rational agents. In this extension the equilibrium of the game is the optimizer of a Lagrangian of the (Probability dist&&on on the joint state of the agents. When the game in question is a team game with constraints, that equilibrium optimizes the expected value of the team game utility, subject to those constraints. One common way to find that equilibrium is to have each agent run a Reinforcement Learning (E) algorithm. PD theory reveals this to be a particular type of search algorithm for minimizing the Lagrangian. Typically that algorithm i s quite inefficient. A more principled alternative is to use a variant of Newton's method to minimize the Lagrangian. Here we compare this alternative to RL-based search in three sets of computer experiments. These are the N Queen s problem and bin-packing problem from the optimization literature, and the Bar problem from the distributed RL literature. Our results confirm that the PD-theory-based approach outperforms the RL-based scheme in all three domains.

Modeling the stylized facts in finance through simple nonlinear adaptive systems

Science.gov (United States)

Hommes, Cars H.

2002-01-01

Recent work on adaptive systems for modeling financial markets is discussed. Financial markets are viewed as evolutionary systems between different, competing trading strategies. Agents are boundedly rational in the sense that they tend to follow strategies that have performed well, according to realized profits or accumulated wealth, in the recent past. Simple technical trading rules may survive evolutionary competition in a heterogeneous world where prices and beliefs co-evolve over time. Evolutionary models can explain important stylized facts, such as fat tails, clustered volatility, and long memory, of real financial series. PMID:12011401

Water Resource Impacts Embedded in the Western US Electrical Energy Trade; Current Patterns and Adaptation to Future Drought

Science.gov (United States)

Adams, E. A.; Herron, S.; Qiu, Y.; Tidwell, V. C.; Ruddell, B. L.

2013-12-01

Water resources are a key element in the global coupled natural-human (CNH) system, because they are tightly coupled with the world's social, environmental, and economic subsystems, and because water resources are under increasing pressure worldwide. A fundamental adaptive tool used especially by cities to overcome local water resource scarcity is the outsourcing of water resource impacts through substitutionary economic trade. This is generally understood as the indirect component of a water footprint, and as ';virtual water' trade. This work employs generalized CNH methods to reveal the trade in water resource impacts embedded in electrical energy within the Western US power grid, and utilizes a general equilibrium economic trade model combined with drought and demand growth constraints to estimate the future status of this trade. Trade in embedded water resource impacts currently increases total water used for electricity production in the Western US and shifts water use to more water-limited States. Extreme drought and large increases in electrical energy demand increase the need for embedded water resource impact trade, while motivating a shift to more water-efficient generation technologies and more water-abundant generating locations. Cities are the largest users of electrical energy, and in the 21st Century will outsource a larger fraction of their water resource impacts through trade. This trade exposes cities to risks associated with disruption of long-distance transmission and distant hydrological droughts.

Social strategy games in communicating trade-offs between mitigation and adaptation in cities

DEFF Research Database (Denmark)

Juhola, Sirkku; Driscoll, Patrick Arthur; Suarez, Pablo

2013-01-01

and mitigation strategies and what kinds of negative and positive synergies can be identified between them. This paper explores how social games can help people to understand the trade-offs between mitigation and adaptation measures in an urban environment and examines the possibilities of using social gaming...... as a research method. Data was collected from Denmark, Finland and the US through organized gaming sessions. The conclusion of the study is that social games are a promising method to understand complex planning problems....

Adaptive order search and tangent-weighted trade-off for motion estimation in H.264

Directory of Open Access Journals (Sweden)

Srinivas Bachu

2018-04-01

Full Text Available Motion estimation and compensation play a major role in video compression to reduce the temporal redundancies of the input videos. A variety of block search patterns have been developed for matching the blocks with reduced computational complexity, without affecting the visual quality. In this paper, block motion estimation is achieved through integrating the square as well as the hexagonal search patterns with adaptive order. The proposed algorithm is called, AOSH (Adaptive Order Square Hexagonal Search algorithm, and it finds the best matching block with a reduced number of search points. The searching function is formulated as a trade-off criterion here. Hence, the tangent-weighted function is newly developed to evaluate the matching point. The proposed AOSH search algorithm and the tangent-weighted trade-off criterion are effectively applied to the block estimation process to enhance the visual quality and the compression performance. The proposed method is validated using three videos namely, football, garden and tennis. The quantitative performance of the proposed method and the existing methods is analysed using the Structural SImilarity Index (SSIM and the Peak Signal to Noise Ratio (PSNR. The results prove that the proposed method offers good visual quality than the existing methods. Keywords: Block motion estimation, Square search, Hexagon search, H.264, Video coding

Improving efficiency in bilateral emission trading

International Nuclear Information System (INIS)

Burtraw, D.; Harrison, K.W.; Turner, P.

1998-01-01

When environmental damages from emissions are spatially nonuniform, permit trading has been modeled most often as a 'pollution offset program' in which emission permits are traded between agents, subject to constraints on ambient air quality. To date the institution envisioned to implement such a program involves trading on a bilateral and sequential basis. However, simulation studies indicate that the sequence of trades may alter the outcome and undermine the cost savings from a pollution offset program. This paper identifies a design for the trading institution that tends to overcome this phenomenon and improve the efficiency of equilibria obtained in a simulation model. We model a bilateral trading process for the reduction of sulfur dioxide emissions with a stochastic description of the sequence of trades within groups of nations in Europe. When trading takes place between disaggregated, stylistic representations of economic enterprises, rather than between national governments, a significantly greater portion of potential savings is achieved. In fact, under most sets of assumptions, approximate first order stochastic dominance is achieved wherein the more decentralized the trading agents, the greater the expected savings from a trading program. 4 figs., 2 tabs., 31 refs

Modelling trading networks and the role of trust

Science.gov (United States)

Barrio, Rafael A.; Govezensky, Tzipe; Ruiz-Gutiérrez, Élfego; Kaski, Kimmo K.

2017-04-01

We present a simple dynamical model for describing trading interactions between agents in a social network by considering only two dynamical variables, namely money and goods or services, that are assumed conserved over the whole time span of the agents' trading transactions. A key feature of the model is that agent-to-agent transactions are governed by the price in units of money per goods, which is dynamically changing, and by a trust variable, which is related to the trading history of each agent. All agents are able to sell or buy, and the decision to do either has to do with the level of trust the buyer has in the seller, the price of the goods and the amount of money and goods at the disposal of the buyer. Here we show the results of extensive numerical calculations under various initial conditions in a random network of agents and compare the results with the available related data. In most cases the agreement between the model results and real data turns out to be fairly good, which allow us to draw some general conclusions as how different trading strategies could affect the distribution of wealth in different kinds of societies. Our calculations reveal the striking effects of trust in commercial relations, namely that trust makes trading links more robust and the wealth distribution more even as well as allows for the existence of a healthy middle class.

Man or machine? Rational trading without information about fundamentals

OpenAIRE

Rossi, Stefano; Tinn, Katrin

2014-01-01

18/09/13 MEB, Working paper, not yet pub. Systematic trading contingent on observed prices by agents uninformed about fundamentals has long been considered at odds with efficient markets populated by rational agents. In this paper we show that price-contingent trading is the equilibrium strategy of rational agents in efficient markets in which there is uncertainty about whether a large trader is informed. In this environment, knowing his own type and past trades (or lack of them) will be e...

The adaptive response of E. coli to low levels of alkylating agent

International Nuclear Information System (INIS)

Jeggo, P.; Defais, M.; Samson, L.; Schendel, P.

1978-01-01

In an attempt to characterise which gene products may be involved in the repair system induced in E. coli by growth on low levels of alkylating agent (the adaptive response) we have analysed mutants deficient in other known pathways of DNA repair for the ability to adapt to MNNG. Adaptive resistance to the killing effects of MNNG seems to require a functional DNA polymerase I whereas resistance to the mutagenic effects can occur in polymerase I deficient strains; similarly killing adaptation could not be observed in a dam3 mutant, which was nonetheless able to show mutational adaptation. These results suggest that these two parts of the adaptive response must, at least to some extent, be separable. Both adaptive responses can be seen in the absence of uvrD + uvrE + -dependent mismatch repair, DNA polymerase II activity, or recF-mediated recombination and they are not affected by decreased levels of adenyl cyclase. The data presented support our earlier conclusion that adaptive resistance to the killing and mutagenic effect of MNNG is the result of previously uncharacterised repair pathways. (orig.) [de

International Organizations and Trade

OpenAIRE

Antras, Pol

2010-01-01

The three central primitives of international trade theory are consumer preferences, factor endowments, and the production technologies that allow firms to transform factors of production into consumer goods. A limitation of traditional trade theory, however, is that the specification of technology treats the mapping between factors of production and final goods as a black box. In practice, the decisions of agents in organizations determine this mapping. Recently, international trade economis...

Cognitive Support using BDI Agent and Adaptive User Modeling

DEFF Research Database (Denmark)

Hossain, Shabbir

2012-01-01

-known framework to measure the individual health status and functioning level. The third goal is to develop an approach for supporting for users with irrational behaviour due to cognitive impairment. To deal with this challenge, a Belief, Desire and Intention (BDI) agent based approach is proposed due to its...... mentalistic characteristics, such as autonomy, adaptivity, extensibility, and human like reasoning capability. Although, BDI is unable to reason about plans, which is important for generating plans based on the current situation to handle the irrational behaviour of the user. An integration of Partially...... Observable Markov Decision Process (POMDP) in the BDI agent is proposed in this thesis to handle the irrational behaviour of the user. The fourth goal represents the implementation of the research approaches and performs validation of the system through experiments. The empirical results of the experiments...

A self-adapting herding model: The agent judge-abilities influence the dynamic behaviors

Science.gov (United States)

Dong, Linrong

2008-10-01

We propose a self-adapting herding model, in which the financial markets consist of agent clusters with different sizes and market desires. The ratio of successful exchange and merger depends on the volatility of the market and the market desires of the agent clusters. The desires are assigned in term of the wealth of the agent clusters when they merge. After an exchange, the beneficial cluster’s desire keeps on the same, the losing one’s desire is altered which is correlative with the agent judge-ability. A parameter R is given to all agents to denote the judge-ability. The numerical calculation shows that the dynamic behaviors of the market are influenced distinctly by R, which includes the exponential magnitudes of the probability distribution of sizes of the agent clusters and the volatility autocorrelation of the returns, the intensity and frequency of the volatility.

Inferring Trade Direction from Intraday Data.

OpenAIRE

Lee, Charles M C; Ready, Mark J

1991-01-01

This paper evaluates alternative methods for classifying individual trades as market buy or market sell orders using intraday trade and quote data. The authors document two potential problems with quote-based methods of trade classification: quotes may be recorded ahead of trades that triggered them, and trades inside the spread are not readily classifiable. These problems are analyzed in the context of the interaction between exchange floor agents. The authors then propose and test relativel...

Adaptively evolved yeast mutants on galactose show trade-offs in carbon utilization on glucose

DEFF Research Database (Denmark)

Hong, Kuk-Ki; Nielsen, Jens

2013-01-01

the molecular mechanisms. In this study, adaptively evolved yeast mutants with improved galactose utilization ability showed impaired glucose utilization. The molecular genetic basis of this trade-off was investigated using a systems biology approach. Transcriptional and metabolic changes resulting from...... the improvement of galactose utilization were found maintained during growth on glucose. Moreover, glucose repression related genes showed conserved expression patterns during growth on both sugars. Mutations in the RAS2 gene that were identified as beneficial for galactose utilization in evolved mutants...

Endogenous Price Bubbles in a Multi-Agent System of the Housing Market.

Science.gov (United States)

Kouwenberg, Roy; Zwinkels, Remco C J

2015-01-01

Economic history shows a large number of boom-bust cycles, with the U.S. real estate market as one of the latest examples. Classical economic models have not been able to provide a full explanation for this type of market dynamics. Therefore, we analyze home prices in the U.S. using an alternative approach, a multi-agent complex system. Instead of the classical assumptions of agent rationality and market efficiency, agents in the model are heterogeneous, adaptive, and boundedly rational. We estimate the multi-agent system with historical house prices for the U.S. market. The model fits the data well and a deterministic version of the model can endogenously produce boom-and-bust cycles on the basis of the estimated coefficients. This implies that trading between agents themselves can create major price swings in absence of fundamental news.

Endogenous Price Bubbles in a Multi-Agent System of the Housing Market.

Directory of Open Access Journals (Sweden)

Roy Kouwenberg

Full Text Available Economic history shows a large number of boom-bust cycles, with the U.S. real estate market as one of the latest examples. Classical economic models have not been able to provide a full explanation for this type of market dynamics. Therefore, we analyze home prices in the U.S. using an alternative approach, a multi-agent complex system. Instead of the classical assumptions of agent rationality and market efficiency, agents in the model are heterogeneous, adaptive, and boundedly rational. We estimate the multi-agent system with historical house prices for the U.S. market. The model fits the data well and a deterministic version of the model can endogenously produce boom-and-bust cycles on the basis of the estimated coefficients. This implies that trading between agents themselves can create major price swings in absence of fundamental news.

Endogenous Price Bubbles in a Multi-Agent System of the Housing Market

Science.gov (United States)

2015-01-01

Economic history shows a large number of boom-bust cycles, with the U.S. real estate market as one of the latest examples. Classical economic models have not been able to provide a full explanation for this type of market dynamics. Therefore, we analyze home prices in the U.S. using an alternative approach, a multi-agent complex system. Instead of the classical assumptions of agent rationality and market efficiency, agents in the model are heterogeneous, adaptive, and boundedly rational. We estimate the multi-agent system with historical house prices for the U.S. market. The model fits the data well and a deterministic version of the model can endogenously produce boom-and-bust cycles on the basis of the estimated coefficients. This implies that trading between agents themselves can create major price swings in absence of fundamental news. PMID:26107740

A detailed heterogeneous agent model for a single asset financial market with trading via an order book.

Science.gov (United States)

Mota Navarro, Roberto; Larralde, Hernán

2017-01-01

We present an agent based model of a single asset financial market that is capable of replicating most of the non-trivial statistical properties observed in real financial markets, generically referred to as stylized facts. In our model agents employ strategies inspired on those used in real markets, and a realistic trade mechanism based on a double auction order book. We study the role of the distinct types of trader on the return statistics: specifically, correlation properties (or lack thereof), volatility clustering, heavy tails, and the degree to which the distribution can be described by a log-normal. Further, by introducing the practice of "profit taking", our model is also capable of replicating the stylized fact related to an asymmetry in the distribution of losses and gains.

Molecular characterization of an adaptive response to alkylating agents in the opportunistic pathogen Aspergillus fumigatus.

Science.gov (United States)

O'Hanlon, Karen A; Margison, Geoffrey P; Hatch, Amy; Fitzpatrick, David A; Owens, Rebecca A; Doyle, Sean; Jones, Gary W

2012-09-01

An adaptive response to alkylating agents based upon the conformational change of a methylphosphotriester (MPT) DNA repair protein to a transcriptional activator has been demonstrated in a number of bacterial species, but this mechanism appears largely absent from eukaryotes. Here, we demonstrate that the human pathogen Aspergillus fumigatus elicits an adaptive response to sub-lethal doses of the mono-functional alkylating agent N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). We have identified genes that encode MPT and O(6)-alkylguanine DNA alkyltransferase (AGT) DNA repair proteins; deletions of either of these genes abolish the adaptive response and sensitize the organism to MNNG. In vitro DNA repair assays confirm the ability of MPT and AGT to repair methylphosphotriester and O(6)-methylguanine lesions respectively. In eukaryotes, the MPT protein is confined to a select group of fungal species, some of which are major mammalian and plant pathogens. The evolutionary origin of the adaptive response is bacterial and rooted within the Firmicutes phylum. Inter-kingdom horizontal gene transfer between Firmicutes and Ascomycete ancestors introduced the adaptive response into the Fungal kingdom. Our data constitute the first detailed characterization of the molecular mechanism of the adaptive response in a lower eukaryote and has applications for development of novel fungal therapeutics targeting this DNA repair system.

Molecular characterization of an adaptive response to alkylating agents in the opportunistic pathogen Aspergillus fumigatus

Science.gov (United States)

O’Hanlon, Karen A.; Margison, Geoffrey P.; Hatch, Amy; Fitzpatrick, David A.; Owens, Rebecca A.; Doyle, Sean; Jones, Gary W.

2012-01-01

An adaptive response to alkylating agents based upon the conformational change of a methylphosphotriester (MPT) DNA repair protein to a transcriptional activator has been demonstrated in a number of bacterial species, but this mechanism appears largely absent from eukaryotes. Here, we demonstrate that the human pathogen Aspergillus fumigatus elicits an adaptive response to sub-lethal doses of the mono-functional alkylating agent N-methyl-N′-nitro-N-nitrosoguanidine (MNNG). We have identified genes that encode MPT and O6-alkylguanine DNA alkyltransferase (AGT) DNA repair proteins; deletions of either of these genes abolish the adaptive response and sensitize the organism to MNNG. In vitro DNA repair assays confirm the ability of MPT and AGT to repair methylphosphotriester and O6-methylguanine lesions respectively. In eukaryotes, the MPT protein is confined to a select group of fungal species, some of which are major mammalian and plant pathogens. The evolutionary origin of the adaptive response is bacterial and rooted within the Firmicutes phylum. Inter-kingdom horizontal gene transfer between Firmicutes and Ascomycete ancestors introduced the adaptive response into the Fungal kingdom. Our data constitute the first detailed characterization of the molecular mechanism of the adaptive response in a lower eukaryote and has applications for development of novel fungal therapeutics targeting this DNA repair system. PMID:22669901

Heterogenous Agents Model with the Worst Out Algorithm

Czech Academy of Sciences Publication Activity Database

Vácha, Lukáš; Vošvrda, Miloslav

-, č. 8 (2006), s. 3-19 ISSN 1801-5999 Institutional research plan: CEZ:AV0Z10750506 Keywords : efficient market hypothesis * fractal market hypothesis * agents' investment horizons * agents' trading strategies * technical trading rules * heterogeneous agent model with stochastic memory * Worst out algorithm Subject RIV: AH - Economics

BTFS: The Border Trade Facilitation System

Energy Technology Data Exchange (ETDEWEB)

Phillips, L.R.

1999-03-18

The author demonstrates the Border Trade Facilitation System (BTFS), an agent-based bilingual e-commerce system built to expedite the regulation, control, and execution of commercial trans-border shipments during the delivery phase. The system was built to serve maquila industries at the US/Mexican border. The BTFS uses foundation technology developed here at Sandia Laboratories' Advanced Information Systems Lab (AISL), including a distributed object substrate, a general-purpose agent development framework, dynamically generated agent-human interaction via the World-Wide Web, and a collaborative agent architecture. This technology is also the substrate for the Multi-Agent Simulation Management System (MASMAS) proposed for demonstration at this conference. The BTFS executes authenticated transactions among agents performing open trading over the Internet. With the BTFS in place, one could conduct secure international transactions from any site with an Internet connection and a web browser. The BTFS is currently being evaluated for commercialization.

Are adaptation costs necessary to build up a local adaptation pattern?

NARCIS (Netherlands)

Magalhães, S.; Blanchet, E.; Egas, M.; Olivieri, I.

2009-01-01

Background: Ecological specialization is pervasive in phytophagous arthropods. In such specialization mode, limits to host range are imposed by trade-offs preventing adaptation to several hosts. The occurrence of such trade-offs is inferred by a pattern of local adaptation, i.e., a negative

Design of a Mobile Agent-Based Adaptive Communication Middleware for Federations of Critical Infrastructure Simulations

Science.gov (United States)

Görbil, Gökçe; Gelenbe, Erol

The simulation of critical infrastructures (CI) can involve the use of diverse domain specific simulators that run on geographically distant sites. These diverse simulators must then be coordinated to run concurrently in order to evaluate the performance of critical infrastructures which influence each other, especially in emergency or resource-critical situations. We therefore describe the design of an adaptive communication middleware that provides reliable and real-time one-to-one and group communications for federations of CI simulators over a wide-area network (WAN). The proposed middleware is composed of mobile agent-based peer-to-peer (P2P) overlays, called virtual networks (VNets), to enable resilient, adaptive and real-time communications over unreliable and dynamic physical networks (PNets). The autonomous software agents comprising the communication middleware monitor their performance and the underlying PNet, and dynamically adapt the P2P overlay and migrate over the PNet in order to optimize communications according to the requirements of the federation and the current conditions of the PNet. Reliable communications is provided via redundancy within the communication middleware and intelligent migration of agents over the PNet. The proposed middleware integrates security methods in order to protect the communication infrastructure against attacks and provide privacy and anonymity to the participants of the federation. Experiments with an initial version of the communication middleware over a real-life networking testbed show that promising improvements can be obtained for unicast and group communications via the agent migration capability of our middleware.

Resource Management for Real-Time Adaptive Agents

Science.gov (United States)

Welch, Lonnie; Chelberg, David; Pfarr, Barbara; Fleeman, David; Parrott, David; Tan, Zhen-Yu; Jain, Shikha; Drews, Frank; Bruggeman, Carl; Shuler, Chris

2003-01-01

Increased autonomy and automation in onboard flight systems offer numerous potential benefits, including cost reduction and greater flexibility. The existence of generic mechanisms for automation is critical for handling unanticipated science events and anomalies where limitations in traditional control software with fixed, predetermined algorithms can mean loss of science data and missed opportunities for observing important terrestrial events. We have developed such a mechanism by adding a Hierarchical Agent-based ReaLTime technology (HART) extension to our Dynamic Resource Management (DRM) middleware. Traditional DRM provides mechanisms to monitor the realtime performance of distributed applications and to move applications among processors to improve real-time performance. In the HART project we have designed and implemented a performance adaptation mechanism to improve reaktime performance. To use this mechanism, applications are developed that can run at various levels of quality. The DRM can choose a setting for the quality level of an application dynamically at run-time in order to manage satellite resource usage more effectively. A groundbased prototype of a satellite system that captures and processes images has also been developed as part of this project to be used as a benchmark for evaluating the resource management framework A significant enhancement of this generic mission-independent framework allows scientists to specify the utility, or "scientific benefit," of science observations under various conditions like cloud cover and compression method. The resource manager then uses these benefit tables to determine in redtime how to set the quality levels for applications to maximize overall system utility as defined by the scientists running the mission. We also show how maintenance functions llke health and safety data can be integrated into the utility framework. Once thls framework has been certified for missions and successfully flight tested it

The Adaptation Law for emissions trading. Part 2. A level playing field for emissions trading?

International Nuclear Information System (INIS)

Simonetti, S.

2010-01-01

To supplement, clarify and simplify the regulations for emission trading, the Amendment Act emission trading II was submitted to the Dutch Lower Chamber end of 2009. This article discusses the pending bill and comments on a number of remarkable stipulations that may be important to the market parties. First a brief overview is provided of the basic principles of emission trading and the players in the CO2 market. [nl

Trade-offs in thermal adaptation: the need for a molecular to ecological integration.

Science.gov (United States)

Pörtner, Hans O; Bennett, Albert F; Bozinovic, Francisco; Clarke, Andrew; Lardies, Marco A; Lucassen, Magnus; Pelster, Bernd; Schiemer, Fritz; Stillman, Jonathon H

2006-01-01

Through functional analyses, integrative physiology is able to link molecular biology with ecology as well as evolutionary biology and is thereby expected to provide access to the evolution of molecular, cellular, and organismic functions; the genetic basis of adaptability; and the shaping of ecological patterns. This paper compiles several exemplary studies of thermal physiology and ecology, carried out at various levels of biological organization from single genes (proteins) to ecosystems. In each of those examples, trade-offs and constraints in thermal adaptation are addressed; these trade-offs and constraints may limit species' distribution and define their level of fitness. For a more comprehensive understanding, the paper sets out to elaborate the functional and conceptual connections among these independent studies and the various organizational levels addressed. This effort illustrates the need for an overarching concept of thermal adaptation that encompasses molecular, organellar, cellular, and whole-organism information as well as the mechanistic links between fitness, ecological success, and organismal physiology. For this data, the hypothesis of oxygen- and capacity-limited thermal tolerance in animals provides such a conceptual framework and allows interpreting the mechanisms of thermal limitation of animals as relevant at the ecological level. While, ideally, evolutionary studies over multiple generations, illustrated by an example study in bacteria, are necessary to test the validity of such complex concepts and underlying hypotheses, animal physiology frequently is constrained to functional studies within one generation. Comparisons of populations in a latitudinal cline, closely related species from different climates, and ontogenetic stages from riverine clines illustrate how evolutionary information can still be gained. An understanding of temperature-dependent shifts in energy turnover, associated with adjustments in aerobic scope and performance

Asia-Pacific Research and Training Network on Trade (ARTNET ...

International Development Research Centre (IDRC) Digital Library (Canada)

During the first phase of support (102568), the Network produced a number of high quality trade policy studies, disseminated the results to policymakers and increased the capacity of research institutions - notably those in the least developed countries - to conduct trade policy ... Agent(e) responsable du CRDI. Due, Evan ...

A detailed heterogeneous agent model for a single asset financial market with trading via an order book.

Directory of Open Access Journals (Sweden)

Roberto Mota Navarro

Full Text Available We present an agent based model of a single asset financial market that is capable of replicating most of the non-trivial statistical properties observed in real financial markets, generically referred to as stylized facts. In our model agents employ strategies inspired on those used in real markets, and a realistic trade mechanism based on a double auction order book. We study the role of the distinct types of trader on the return statistics: specifically, correlation properties (or lack thereof, volatility clustering, heavy tails, and the degree to which the distribution can be described by a log-normal. Further, by introducing the practice of "profit taking", our model is also capable of replicating the stylized fact related to an asymmetry in the distribution of losses and gains.

Adaptive tracking control of leader-following linear multi-agent systems with external disturbances

Science.gov (United States)

Lin, Hanquan; Wei, Qinglai; Liu, Derong; Ma, Hongwen

2016-10-01

In this paper, the consensus problem for leader-following linear multi-agent systems with external disturbances is investigated. Brownian motions are used to describe exogenous disturbances. A distributed tracking controller based on Riccati inequalities with an adaptive law for adjusting coupling weights between neighbouring agents is designed for leader-following multi-agent systems under fixed and switching topologies. In traditional distributed static controllers, the coupling weights depend on the communication graph. However, coupling weights associated with the feedback gain matrix in our method are updated by state errors between neighbouring agents. We further present the stability analysis of leader-following multi-agent systems with stochastic disturbances under switching topology. Most traditional literature requires the graph to be connected all the time, while the communication graph is only assumed to be jointly connected in this paper. The design technique is based on Riccati inequalities and algebraic graph theory. Finally, simulations are given to show the validity of our method.

Highly adaptable triple-negative breast cancer cells as a functional model for testing anticancer agents.

Directory of Open Access Journals (Sweden)

Balraj Singh

Full Text Available A major obstacle in developing effective therapies against solid tumors stems from an inability to adequately model the rare subpopulation of panresistant cancer cells that may often drive the disease. We describe a strategy for optimally modeling highly abnormal and highly adaptable human triple-negative breast cancer cells, and evaluating therapies for their ability to eradicate such cells. To overcome the shortcomings often associated with cell culture models, we incorporated several features in our model including a selection of highly adaptable cancer cells based on their ability to survive a metabolic challenge. We have previously shown that metabolically adaptable cancer cells efficiently metastasize to multiple organs in nude mice. Here we show that the cancer cells modeled in our system feature an embryo-like gene expression and amplification of the fat mass and obesity associated gene FTO. We also provide evidence of upregulation of ZEB1 and downregulation of GRHL2 indicating increased epithelial to mesenchymal transition in metabolically adaptable cancer cells. Our results obtained with a variety of anticancer agents support the validity of the model of realistic panresistance and suggest that it could be used for developing anticancer agents that would overcome panresistance.

Adaptive learning in agents behaviour: A framework for electricity markets simulation

DEFF Research Database (Denmark)

Pinto, Tiago; Vale, Zita; Sousa, Tiago M.

2014-01-01

decision support to MASCEM's negotiating agents so that they can properly achieve their goals. ALBidS uses artificial intelligence methodologies and data analysis algorithms to provide effective adaptive learning capabilities to such negotiating entities. The main contribution is provided by a methodology...... that combines several distinct strategies to build actions proposals, so that the best can be chosen at each time, depending on the context and simulation circumstances. The choosing process includes reinforcement learning algorithms, a mechanism for negotiating contexts analysis, a mechanism for the management...... allows integrating different strategic approaches for electricity market negotiations, and choosing the most appropriate one at each time, for each different negotiation context. This methodology is integrated in ALBidS (Adaptive Learning strategic Bidding System) – a multiagent system that provides...

Smart Meter Aware Domestic Energy Trading Agents

NARCIS (Netherlands)

Capodieci, Nicola; Pagani, Giuliano Andrea; Cabri, Giacomo; Aiello, Marco

2011-01-01

The domestic energy market is changing with the increasing availability of energy micro-generating facilities. On the long run, households will have the possibility to trade energy for purchasing to and for selling from a number of different actors. We model such a futuristic scenario using software

Thermotolerant Yeast Strains Adapted by Laboratory Evolution Show Trade-Off at Ancestral Temperatures and Preadaptation to Other Stresses.

Science.gov (United States)

Caspeta, Luis; Nielsen, Jens

2015-07-21

A major challenge for the production of ethanol from biomass-derived feedstocks is to develop yeasts that can sustain growth under the variety of inhibitory conditions present in the production process, e.g., high osmolality, high ethanol titers, and/or elevated temperatures (≥ 40 °C). Using adaptive laboratory evolution, we previously isolated seven Saccharomyces cerevisiae strains with improved growth at 40 °C. Here, we show that genetic adaptations to high temperature caused a growth trade-off at ancestral temperatures, reduced cellular functions, and improved tolerance of other stresses. Thermotolerant yeast strains showed horizontal displacement of their thermal reaction norms to higher temperatures. Hence, their optimal and maximum growth temperatures increased by about 3 °C, whereas they showed a growth trade-off at temperatures below 34 °C. Computational analysis of the physical properties of proteins showed that the lethal temperature for yeast is around 49 °C, as a large fraction of the yeast proteins denature above this temperature. Our analysis also indicated that the number of functions involved in controlling the growth rate decreased in the thermotolerant strains compared with the number in the ancestral strain. The latter is an advantageous attribute for acquiring thermotolerance and correlates with the reduction of yeast functions associated with loss of respiration capacity. This trait caused glycerol overproduction that was associated with the growth trade-off at ancestral temperatures. In combination with altered sterol composition of cellular membranes, glycerol overproduction was also associated with yeast osmotolerance and improved tolerance of high concentrations of glucose and ethanol. Our study shows that thermal adaptation of yeast is suitable for improving yeast resistance to inhibitory conditions found in industrial ethanol production processes. Yeast thermotolerance can significantly reduce the production costs of biomass

Investigation of autistic traits through strategic decision-making in games with adaptive agents.

Science.gov (United States)

Craig, Alexis B; Grossman, Emily; Krichmar, Jeffrey L

2017-07-17

Autism Spectrum Disorders are characterized by difficulties in communicating and cooperating with other people. Impairment in Theory of Mind (ToM), the ability to infer what another person is thinking, may contribute to these social deficits. The present study assesses the relationship between autistic traits and decision-making in a socioeconomic game environment that measures ToM and cooperation. We quantified participant strategy during game play with computer agents that simulated aspects of ToM or fixed strategy agents with static behaviors or heuristics. Individuals with higher Autism Quotient (AQ) scores cooperated less than subjects with low AQ scores with the ToM agents. In contrast, subjects with higher AQ scores cooperated more with fixed strategy agents. Additionally, subjects with higher AQ scores spent more time than low AQ subjects signaling cooperative intent in games with fixed strategy agents while spending less time signaling cooperation with adaptive agents, indicating a preference toward systemizing behaviors in the face of uncertainty. We conclude that individuals with high levels of autistic traits are less likely to utilize ToM as a cognitive strategy, even when it is beneficial, to achieve a desired outcome.

An Agent-based Modeling of Water-Food Nexus towards Sustainable Management of Urban Water Resources

Science.gov (United States)

Esmaeili, N.; Kanta, L.

2017-12-01

Growing population, urbanization, and climate change have put tremendous stress on water systems in many regions. A shortage in water system not only affects water users of a municipality but also that of food system. About 70% of global water is withdrawn for agriculture; livestock and dairy productions are also dependent on water availability. Although researchers and policy makers have identified and emphasized the water-food (WF) nexus in recent decade, most existing WF models offer strategies to reduce trade-offs and to generate benefits without considering feedback loops and adaptations between those systems. Feedback loops between water and food system can help understand long-term behavioral trends between water users of the integrated WF system which, in turn, can help manage water resources sustainably. An Agent-based modeling approach is applied here to develop a conceptual framework of WF systems. All water users in this system are modeled as agents, who are capable of making decisions and can adapt new behavior based on inputs from other agents in a shared environment through a set of logical and mathematical rules. Residential and commercial/industrial consumers are represented as municipal agents; crop, livestock, and dairy farmers are represented as food agents; and water management officials are represented as policy agent. During the period of water shortage, policy agent will propose/impose various water conservation measures, such as adapting water-efficient technologies, banning outdoor irrigation, implementing supplemental irrigation, using recycled water for livestock/dairy production, among others. Municipal and food agents may adapt conservation strategies and will update their demand accordingly. Emergent properties of the WF nexus will arise through dynamic interactions between various actors of water and food system. This model will be implemented to a case study for resource allocation and future policy development.

Social adaptation in multi-agent model of linguistic categorization is affected by network information flow.

Science.gov (United States)

Zubek, Julian; Denkiewicz, Michał; Barański, Juliusz; Wróblewski, Przemysław; Rączaszek-Leonardi, Joanna; Plewczynski, Dariusz

2017-01-01

This paper explores how information flow properties of a network affect the formation of categories shared between individuals, who are communicating through that network. Our work is based on the established multi-agent model of the emergence of linguistic categories grounded in external environment. We study how network information propagation efficiency and the direction of information flow affect categorization by performing simulations with idealized network topologies optimizing certain network centrality measures. We measure dynamic social adaptation when either network topology or environment is subject to change during the experiment, and the system has to adapt to new conditions. We find that both decentralized network topology efficient in information propagation and the presence of central authority (information flow from the center to peripheries) are beneficial for the formation of global agreement between agents. Systems with central authority cope well with network topology change, but are less robust in the case of environment change. These findings help to understand which network properties affect processes of social adaptation. They are important to inform the debate on the advantages and disadvantages of centralized systems.

Building an adaptive agent to monitor and repair the electrical power system of an orbital satellite

Science.gov (United States)

Tecuci, Gheorghe; Hieb, Michael R.; Dybala, Tomasz

1995-01-01

Over several years we have developed a multistrategy apprenticeship learning methodology for building knowledge-based systems. Recently we have developed and applied our methodology to building intelligent agents. This methodology allows a subject matter expert to build an agent in the same way in which the expert would teach a human apprentice. The expert will give the agent specific examples of problems and solutions, explanations of these solutions, or supervise the agent as it solves new problems. During such interactions, the agent learns general rules and concepts, continuously extending and improving its knowledge base. In this paper we present initial results on applying this methodology to build an intelligent adaptive agent for monitoring and repair of the electrical power system of an orbital satellite, stressing the interaction with the expert during apprenticeship learning.

A Software Environment for an Adaptive Human-Aware Software Agent Supporting Attention-Demanding Tasks

NARCIS (Netherlands)

Bosse, T.; Memon, Z.A.; Oorburg, R.; Umair, M.; Treur, J.; de Vos, M.

2011-01-01

This paper presents a software environment providing human-aware ambient support for a human performing a task that demands substantial amounts of attention. The agent obtains human attention-awareness in an adaptive manner by use of a dynamical model of human attention, gaze sensoring by an

Equity Trading under Heterogeneity in Ambiguity

DEFF Research Database (Denmark)

Alonso, Irasema; Prado, Mauricio

-relevant, but hard-to-interpret information: a situation like that during the onset of the recent crisis in financial markets. During this episode, market participants appeared unsure of the values of a variety of assets, trading all but stopped. Ambiguity aversion, it appears to us, offers a tractable way......-participation - a drastic form of trading less - in the ambiguity-ridden market by certain agents (here we have in mind those with higher levels of ambiguity). This endogenous limited participation on the market also has implications for the relative wealth of agents in an economy. The dynamics of the wealth distribution...

Interacting agents in finance

NARCIS (Netherlands)

Hommes, C.; Durlauf, S.N.; Blume, L.E.

2008-01-01

Interacting agents in finance represent a behavioural, agent-based approach in which financial markets are viewed as complex adaptive systems consisting of many boundedly rational agents interacting through simple heterogeneous investment strategies, constantly adapting their behaviour in response

Evaluation of CO2 free electricity trading market in Japan by multi-agent simulations

International Nuclear Information System (INIS)

Sichao, Kan; Yamamoto, Hiromi; Yamaji, Kenji

2010-01-01

As of November 2008, a new market, the CO 2 free electricity market, started pilot trading within the Japan Electric Power Exchange (JEPX). The electricity in this market comes from renewable resources, nuclear or fossil thermal power with CDM credits. The demanders of the CO 2 free electricity are supposed to be the power companies with high emission rates. In this paper, we analyzed the effects of the new market by using a multi-agent based model to simulate the markets. From our simulation results, we found that the demander, under strict CO 2 emission regulations, tends to buy more electricity from the new CO 2 free market even though the price of this market is higher than that of the normal power exchange market. Suppliers with hydro or nuclear power plants only sell their electricity to the CO 2 free market, and suppliers with coal power plants also enter this market (with CDM credits). The media and peak demands in the normal market are met mainly by electricity from LNG power plants. We also compared the results from the multi-agent approach with those from the least-cost planning approach and found that the results of the two methods were similar. (author)

Heterogeneous Agents Model with the Worst Out Algorithm

Czech Academy of Sciences Publication Activity Database

Vošvrda, Miloslav; Vácha, Lukáš

I, č. 1 (2007), s. 54-66 ISSN 1802-4696 R&D Projects: GA MŠk(CZ) LC06075; GA ČR(CZ) GA402/06/0990 Grant - others:GA UK(CZ) 454/2004/A-EK/FSV Institutional research plan: CEZ:AV0Z10750506 Keywords : Efficient Market s Hypothesis * Fractal Market Hypothesis * agents' investment horizons * agents' trading strategies * technical trading rules * heterogeneous agent model with stochastic memory * Worst out Algorithm Subject RIV: AH - Economics

Adaptive pathways and coupled infrastructure: seven centuries of adaptation to water risk and the production of vulnerability in Mexico City

Directory of Open Access Journals (Sweden)

Beth Tellman

2018-03-01

Full Text Available Infrastructure development is central to the processes that abate and produce vulnerabilities in cities. Urban actors, especially those with power and authority, perceive and interpret vulnerability and decide when and how to adapt. When city managers use infrastructure to reduce urban risk in the complex, interconnected city system, new fragilities are introduced because of inherent system feedbacks. We trace the interactions between system dynamics and decision-making processes over 700 years of Mexico City's adaptations to water risks, focusing on the decision cycles of public infrastructure providers (in this case, government authorities. We bring together two lenses in examining this history: robustness-vulnerability trade-offs to explain the evolution of systemic risk dynamics mediated by feedback control, and adaptation pathways to focus on the evolution of decision cycles that motivate significant infrastructure investments. Drawing from historical accounts, archeological evidence, and original research on water, engineering, and cultural history, we examine adaptation pathways of humans settlement, water supply, and flood risk. Mexico City's history reveals insights that expand the theory of coupled infrastructure and lessons salient to contemporary urban risk management: (1 adapting by spatially externalizing risks can backfire: as cities expand, such risks become endogenous; (2 over time, adaptation pathways initiated to address specific risks may begin to intersect, creating complex trade-offs in risk management; and (3 city authorities are agents of risk production: even in the face of new exogenous risks (climate change, acknowledging and managing risks produced endogenously may prove more adaptive. History demonstrates that the very best solutions today may present critical challenges for tomorrow, and that collectively people have far more agency in and influence over the complex systems we live in than is often acknowledged.

The value and adaptation of plant uptake models in international trade of produce treated with crop protection products

DEFF Research Database (Denmark)

Kennedy, C.; Anderson, J.; Snyder, N.

2010-01-01

Crop Protection Product (CPP) national registrations and/or international trade require magnitude and decline of residue data for treated produce. These data are used to assess human dietary risk and establish legal limits (Maximum Residue Limits, MRLs) for traded produce. The ability to predict...... residues based on limited data sets affords business value by enabling informed product development decisions about the likelihood for MRL compliance for varied product use scenarios. Predicted residues can additionally support the design and conduct of time-constrained interdependent studies required...... for product registrations. While advances in predicting residues for the case of foliar applications of CPPs have been achieved, predictions for the case of soil applications of CPPs provide additional challenge. The adaptation of a newly developed dynamic model to CPP product use scenarios will be explored...

From General Game Descriptions to a Market Specification Language for General Trading Agents

Science.gov (United States)

Thielscher, Michael; Zhang, Dongmo

The idea behind General Game Playing is to build systems that, instead of being programmed for one specific task, are intelligent and flexible enough to negotiate an unknown environment solely on the basis of the rules which govern it. In this paper, we argue that this principle has the great potential to bring to a new level artificially intelligent systems in other application areas as well. Our specific interest lies in General Trading Agents, which are able to understand the rules of unknown markets and then to actively participate in them without human intervention. To this end, we extend the general Game Description Language into a language that allows to formally describe arbitrary markets in such a way that these specifications can be automatically processed by a computer. We present both syntax and a transition-based semantics for this Market Specification Language and illustrate its expressive power by presenting axiomatizations of several well-known auction types.

Resilience through adaptation.

Directory of Open Access Journals (Sweden)

Guus A Ten Broeke

Full Text Available Adaptation of agents through learning or evolution is an important component of the resilience of Complex Adaptive Systems (CAS. Without adaptation, the flexibility of such systems to cope with outside pressures would be much lower. To study the capabilities of CAS to adapt, social simulations with agent-based models (ABMs provide a helpful tool. However, the value of ABMs for studying adaptation depends on the availability of methodologies for sensitivity analysis that can quantify resilience and adaptation in ABMs. In this paper we propose a sensitivity analysis methodology that is based on comparing time-dependent probability density functions of output of ABMs with and without agent adaptation. The differences between the probability density functions are quantified by the so-called earth-mover's distance. We use this sensitivity analysis methodology to quantify the probability of occurrence of critical transitions and other long-term effects of agent adaptation. To test the potential of this new approach, it is used to analyse the resilience of an ABM of adaptive agents competing for a common-pool resource. Adaptation is shown to contribute positively to the resilience of this ABM. If adaptation proceeds sufficiently fast, it may delay or avert the collapse of this system.

Resilience through adaptation.

Science.gov (United States)

Ten Broeke, Guus A; van Voorn, George A K; Ligtenberg, Arend; Molenaar, Jaap

2017-01-01

Adaptation of agents through learning or evolution is an important component of the resilience of Complex Adaptive Systems (CAS). Without adaptation, the flexibility of such systems to cope with outside pressures would be much lower. To study the capabilities of CAS to adapt, social simulations with agent-based models (ABMs) provide a helpful tool. However, the value of ABMs for studying adaptation depends on the availability of methodologies for sensitivity analysis that can quantify resilience and adaptation in ABMs. In this paper we propose a sensitivity analysis methodology that is based on comparing time-dependent probability density functions of output of ABMs with and without agent adaptation. The differences between the probability density functions are quantified by the so-called earth-mover's distance. We use this sensitivity analysis methodology to quantify the probability of occurrence of critical transitions and other long-term effects of agent adaptation. To test the potential of this new approach, it is used to analyse the resilience of an ABM of adaptive agents competing for a common-pool resource. Adaptation is shown to contribute positively to the resilience of this ABM. If adaptation proceeds sufficiently fast, it may delay or avert the collapse of this system.

A Diversified Investment Strategy Using Autonomous Agents

Science.gov (United States)

Barbosa, Rui Pedro; Belo, Orlando

In a previously published article, we presented an architecture for implementing agents with the ability to trade autonomously in the Forex market. At the core of this architecture is an ensemble of classification and regression models that is used to predict the direction of the price of a currency pair. In this paper, we will describe a diversified investment strategy consisting of five agents which were implemented using that architecture. By simulating trades with 18 months of out-of-sample data, we will demonstrate that data mining models can produce profitable predictions, and that the trading risk can be diminished through investment diversification.

Adaptive fuzzy wavelet network control of second order multi-agent systems with unknown nonlinear dynamics.

Science.gov (United States)

Taheri, Mehdi; Sheikholeslam, Farid; Najafi, Majddedin; Zekri, Maryam

2017-07-01

In this paper, consensus problem is considered for second order multi-agent systems with unknown nonlinear dynamics under undirected graphs. A novel distributed control strategy is suggested for leaderless systems based on adaptive fuzzy wavelet networks. Adaptive fuzzy wavelet networks are employed to compensate for the effect of unknown nonlinear dynamics. Moreover, the proposed method is developed for leader following systems and leader following systems with state time delays. Lyapunov functions are applied to prove uniformly ultimately bounded stability of closed loop systems and to obtain adaptive laws. Three simulation examples are presented to illustrate the effectiveness of the proposed control algorithms. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

Trade-Offs of Escherichia coli Adaptation to an Intracellular Lifestyle in Macrophages.

Directory of Open Access Journals (Sweden)

M Azevedo

Full Text Available The bacterium Escherichia coli exhibits remarkable genomic and phenotypic variation, with some pathogenic strains having evolved to survive and even replicate in the harsh intra-macrophage environment. The rate and effects of mutations that can cause pathoadaptation are key determinants of the pace at which E. coli can colonize such niches and become pathogenic. We used experimental evolution to determine the speed and evolutionary paths undertaken by a commensal strain of E. coli when adapting to intracellular life. We estimated the acquisition of pathoadaptive mutations at a rate of 10-6 per genome per generation, resulting in the fixation of more virulent strains in less than a hundred generations. Whole genome sequencing of independently evolved clones showed that the main targets of intracellular adaptation involved loss of function mutations in genes implicated in the assembly of the lipopolysaccharide core, iron metabolism and di- and tri-peptide transport, namely rfaI, fhuA and tppB, respectively. We found a substantial amount of antagonistic pleiotropy in evolved populations, as well as metabolic trade-offs, commonly found in intracellular bacteria with reduced genome sizes. Overall, the low levels of clonal interference detected indicate that the first steps of the transition of a commensal E. coli into intracellular pathogens are dominated by a few pathoadaptive mutations with very strong effects.

Modeling Multi-Mobile Agents System Based on Coalition Signature Mechanism Using UML

Institute of Scientific and Technical Information of China (English)

SUNZhixin; HUANGHaiping; WANGRuchuan

2004-01-01

With the development of electronic commerce and agent techniques, multi-mobile agents cooperation can not only improve the efficiency of electronic business trade, but more importantly, it has a comprehensive applicative value in solving the security issues of mobile agent system. This paper firstly describes the mechanism of multi-mobile agents coalition signature aiming at the system security. Subsequently it brings forward a basic architecture of Multi-mobile agents system (MMAS) based on the design pattern of multi-mobile agents. The paper uses the diagrs_rn of UML, such as use case diagram, class diagram and sequence diagram to build the detailed model of the coalition signature and multi-mobile agents cooperation results. Through security analysis, we find that multimobile agents cooperation and interaction can solve some security problems of mobile agents in transfer, and also it can improve the efficiency of business trade. These results indicate that MMAS has a high security performance and can be widely used in E-commerce trade.

Robust adaptive fault-tolerant control for leader-follower flocking of uncertain multi-agent systems with actuator failure.

Science.gov (United States)

Yazdani, Sahar; Haeri, Mohammad

2017-11-01

In this work, we study the flocking problem of multi-agent systems with uncertain dynamics subject to actuator failure and external disturbances. By considering some standard assumptions, we propose a robust adaptive fault tolerant protocol for compensating of the actuator bias fault, the partial loss of actuator effectiveness fault, the model uncertainties, and external disturbances. Under the designed protocol, velocity convergence of agents to that of virtual leader is guaranteed while the connectivity preservation of network and collision avoidance among agents are ensured as well. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

Agent-based station for on-line diagnostics by self-adaptive laser Doppler vibrometry

Science.gov (United States)

Serafini, S.; Paone, N.; Castellini, P.

2013-12-01

A self-adaptive diagnostic system based on laser vibrometry is proposed for quality control of mechanical defects by vibration testing; it is developed for appliances at the end of an assembly line, but its characteristics are generally suited for testing most types of electromechanical products. It consists of a laser Doppler vibrometer, equipped with scanning mirrors and a camera, which implements self-adaptive bahaviour for optimizing the measurement. The system is conceived as a Quality Control Agent (QCA) and it is part of a Multi Agent System that supervises all the production line. The QCA behaviour is defined so to minimize measurement uncertainty during the on-line tests and to compensate target mis-positioning under guidance of a vision system. Best measurement conditions are reached by maximizing the amplitude of the optical Doppler beat signal (signal quality) and consequently minimize uncertainty. In this paper, the optimization strategy for measurement enhancement achieved by the down-hill algorithm (Nelder-Mead algorithm) and its effect on signal quality improvement is discussed. Tests on a washing machine in controlled operating conditions allow to evaluate the efficacy of the method; significant reduction of noise on vibration velocity spectra is observed. Results from on-line tests are presented, which demonstrate the potential of the system for industrial quality control.

Agent-based station for on-line diagnostics by self-adaptive laser Doppler vibrometry.

Science.gov (United States)

Serafini, S; Paone, N; Castellini, P

2013-12-01

A self-adaptive diagnostic system based on laser vibrometry is proposed for quality control of mechanical defects by vibration testing; it is developed for appliances at the end of an assembly line, but its characteristics are generally suited for testing most types of electromechanical products. It consists of a laser Doppler vibrometer, equipped with scanning mirrors and a camera, which implements self-adaptive bahaviour for optimizing the measurement. The system is conceived as a Quality Control Agent (QCA) and it is part of a Multi Agent System that supervises all the production line. The QCA behaviour is defined so to minimize measurement uncertainty during the on-line tests and to compensate target mis-positioning under guidance of a vision system. Best measurement conditions are reached by maximizing the amplitude of the optical Doppler beat signal (signal quality) and consequently minimize uncertainty. In this paper, the optimization strategy for measurement enhancement achieved by the down-hill algorithm (Nelder-Mead algorithm) and its effect on signal quality improvement is discussed. Tests on a washing machine in controlled operating conditions allow to evaluate the efficacy of the method; significant reduction of noise on vibration velocity spectra is observed. Results from on-line tests are presented, which demonstrate the potential of the system for industrial quality control.

Sustainable Society Formed by Unselfish Agents

Science.gov (United States)

Kikuchi, Toshiko

It has been pointed out that if the social configuration of the three relations (market, communal and obligatory relations) is not balanced, a market based society as a total system fails. Using multi-agent simulations, this paper shows that a sustainable society is formed when all three relations are integrated and function respectively. When agent trades are based on the market mechanism (i.e., agents act in their own interest and thus only market relations exist), weak agents who cannot perform transactions die. If a compulsory tax is imposed to enable all weak agents to survive (i.e., obligatory relations exist), then the fiscal deficit increases. On the other hand, if agents who have excess income undertake the unselfish action of distributing their surplus to the weak agents (i.e., communal relations exist), then trade volume increases. It is shown that the existence of unselfish agents is necessary for the realization of a sustainable society. However, the survival of all agents is difficult in a communal society. In an artificial society, for all agents survive and fiscal balance to be maintained, all three social relations need to be fully integrated. These results show that adjusting the balance of the three social relations well lead to the realization of a sustainable society.

Adaptive Load Balancing of Parallel Applications with Multi-Agent Reinforcement Learning on Heterogeneous Systems

Directory of Open Access Journals (Sweden)

Johan Parent

2004-01-01

Full Text Available We report on the improvements that can be achieved by applying machine learning techniques, in particular reinforcement learning, for the dynamic load balancing of parallel applications. The applications being considered in this paper are coarse grain data intensive applications. Such applications put high pressure on the interconnect of the hardware. Synchronization and load balancing in complex, heterogeneous networks need fast, flexible, adaptive load balancing algorithms. Viewing a parallel application as a one-state coordination game in the framework of multi-agent reinforcement learning, and by using a recently introduced multi-agent exploration technique, we are able to improve upon the classic job farming approach. The improvements are achieved with limited computation and communication overhead.

Modeling the Internet of Things, Self-Organizing and Other Complex Adaptive Communication Networks: A Cognitive Agent-Based Computing Approach.

Directory of Open Access Journals (Sweden)

Samreen Laghari

Full Text Available Computer Networks have a tendency to grow at an unprecedented scale. Modern networks involve not only computers but also a wide variety of other interconnected devices ranging from mobile phones to other household items fitted with sensors. This vision of the "Internet of Things" (IoT implies an inherent difficulty in modeling problems.It is practically impossible to implement and test all scenarios for large-scale and complex adaptive communication networks as part of Complex Adaptive Communication Networks and Environments (CACOONS. The goal of this study is to explore the use of Agent-based Modeling as part of the Cognitive Agent-based Computing (CABC framework to model a Complex communication network problem.We use Exploratory Agent-based Modeling (EABM, as part of the CABC framework, to develop an autonomous multi-agent architecture for managing carbon footprint in a corporate network. To evaluate the application of complexity in practical scenarios, we have also introduced a company-defined computer usage policy.The conducted experiments demonstrated two important results: Primarily CABC-based modeling approach such as using Agent-based Modeling can be an effective approach to modeling complex problems in the domain of IoT. Secondly, the specific problem of managing the Carbon footprint can be solved using a multiagent system approach.

Modeling the Internet of Things, Self-Organizing and Other Complex Adaptive Communication Networks: A Cognitive Agent-Based Computing Approach.

Science.gov (United States)

Laghari, Samreen; Niazi, Muaz A

2016-01-01

Computer Networks have a tendency to grow at an unprecedented scale. Modern networks involve not only computers but also a wide variety of other interconnected devices ranging from mobile phones to other household items fitted with sensors. This vision of the "Internet of Things" (IoT) implies an inherent difficulty in modeling problems. It is practically impossible to implement and test all scenarios for large-scale and complex adaptive communication networks as part of Complex Adaptive Communication Networks and Environments (CACOONS). The goal of this study is to explore the use of Agent-based Modeling as part of the Cognitive Agent-based Computing (CABC) framework to model a Complex communication network problem. We use Exploratory Agent-based Modeling (EABM), as part of the CABC framework, to develop an autonomous multi-agent architecture for managing carbon footprint in a corporate network. To evaluate the application of complexity in practical scenarios, we have also introduced a company-defined computer usage policy. The conducted experiments demonstrated two important results: Primarily CABC-based modeling approach such as using Agent-based Modeling can be an effective approach to modeling complex problems in the domain of IoT. Secondly, the specific problem of managing the Carbon footprint can be solved using a multiagent system approach.

Agent-based simulation of a financial market

Science.gov (United States)

Raberto, Marco; Cincotti, Silvano; Focardi, Sergio M.; Marchesi, Michele

2001-10-01

This paper introduces an agent-based artificial financial market in which heterogeneous agents trade one single asset through a realistic trading mechanism for price formation. Agents are initially endowed with a finite amount of cash and a given finite portfolio of assets. There is no money-creation process; the total available cash is conserved in time. In each period, agents make random buy and sell decisions that are constrained by available resources, subject to clustering, and dependent on the volatility of previous periods. The model proposed herein is able to reproduce the leptokurtic shape of the probability density of log price returns and the clustering of volatility. Implemented using extreme programming and object-oriented technology, the simulator is a flexible computational experimental facility that can find applications in both academic and industrial research projects.

Clastogenic adaption of Vicia faba root tip meristem cells after consecutive treatments with S-phase dependent and S-phase independent agents

International Nuclear Information System (INIS)

Heindorff, K.; Schubert, I.; Rieger, R.; Michaelis, A.

1987-01-01

Pretreatment of Vicia faba root tip meristems with low doses of S-phase independent clastogens, such as X-rays or bleomycin, prior to a high (challenge) dose of S-phase dependent clastogens, such as alkylating agents (TEM, Trenimon) or the pyridazine derivative MH, led to decreased challenge treatment-induced aberration frequencies, i.e., clastogenic adaptation. Using the inverse treatment sequence bleomycin and MH proved to be able to substitute for each other in provoking clastogenic (cross) adaptation while bleomycin and alkylating agents were unable to do so. The data support the assumption of inducible cellular functions that become triggered by low clastogen doses and additionally describe some particular properties of bleomycin when used for conditioning. Bleomycin proved to be capable to exert protection independent of the agent used for challenge treatment. (author)

Intelligent agents: adaptation of autonomous bimodal microsystems

Science.gov (United States)

Smith, Patrice; Terry, Theodore B.

2014-03-01

Autonomous bimodal microsystems exhibiting survivability behaviors and characteristics are able to adapt dynamically in any given environment. Equipped with a background blending exoskeleton it will have the capability to stealthily detect and observe a self-chosen viewing area while exercising some measurable form of selfpreservation by either flying or crawling away from a potential adversary. The robotic agent in this capacity activates a walk-fly algorithm, which uses a built in multi-sensor processing and navigation subsystem or algorithm for visual guidance and best walk-fly path trajectory to evade capture or annihilation. The research detailed in this paper describes the theoretical walk-fly algorithm, which broadens the scope of spatial and temporal learning, locomotion, and navigational performances based on optical flow signals necessary for flight dynamics and walking stabilities. By observing a fly's travel and avoidance behaviors; and, understanding the reverse bioengineering research efforts of others, we were able to conceptualize an algorithm, which works in conjunction with decisionmaking functions, sensory processing, and sensorimotor integration. Our findings suggest that this highly complex decentralized algorithm promotes inflight or terrain travel mobile stability which is highly suitable for nonaggressive micro platforms supporting search and rescue (SAR), and chemical and explosive detection (CED) purposes; a necessity in turbulent, non-violent structured or unstructured environments.

The Basic Immune Simulator: An agent-based model to study the interactions between innate and adaptive immunity

Directory of Open Access Journals (Sweden)

Orosz Charles G

2007-09-01

Full Text Available Abstract Background We introduce the Basic Immune Simulator (BIS, an agent-based model created to study the interactions between the cells of the innate and adaptive immune system. Innate immunity, the initial host response to a pathogen, generally precedes adaptive immunity, which generates immune memory for an antigen. The BIS simulates basic cell types, mediators and antibodies, and consists of three virtual spaces representing parenchymal tissue, secondary lymphoid tissue and the lymphatic/humoral circulation. The BIS includes a Graphical User Interface (GUI to facilitate its use as an educational and research tool. Results The BIS was used to qualitatively examine the innate and adaptive interactions of the immune response to a viral infection. Calibration was accomplished via a parameter sweep of initial agent population size, and comparison of simulation patterns to those reported in the basic science literature. The BIS demonstrated that the degree of the initial innate response was a crucial determinant for an appropriate adaptive response. Deficiency or excess in innate immunity resulted in excessive proliferation of adaptive immune cells. Deficiency in any of the immune system components increased the probability of failure to clear the simulated viral infection. Conclusion The behavior of the BIS matches both normal and pathological behavior patterns in a generic viral infection scenario. Thus, the BIS effectively translates mechanistic cellular and molecular knowledge regarding the innate and adaptive immune response and reproduces the immune system's complex behavioral patterns. The BIS can be used both as an educational tool to demonstrate the emergence of these patterns and as a research tool to systematically identify potential targets for more effective treatment strategies for diseases processes including hypersensitivity reactions (allergies, asthma, autoimmunity and cancer. We believe that the BIS can be a useful addition to

Forest management under climatic and social uncertainty: trade-offs between reducing climate change impacts and fostering adaptive capacity.

Science.gov (United States)

Seidl, Rupert; Lexer, Manfred J

2013-01-15

The unabated continuation of anthropogenic greenhouse gas emissions and the lack of an international consensus on a stringent climate change mitigation policy underscore the importance of adaptation for coping with the all but inevitable changes in the climate system. Adaptation measures in forestry have particularly long lead times. A timely implementation is thus crucial for reducing the considerable climate vulnerability of forest ecosystems. However, since future environmental conditions as well as future societal demands on forests are inherently uncertain, a core requirement for adaptation is robustness to a wide variety of possible futures. Here we explicitly address the roles of climatic and social uncertainty in forest management, and tackle the question of robustness of adaptation measures in the context of multi-objective sustainable forest management (SFM). We used the Austrian Federal Forests (AFF) as a case study, and employed a comprehensive vulnerability assessment framework based on ecosystem modeling, multi-criteria decision analysis, and practitioner participation. We explicitly considered climate uncertainty by means of three climate change scenarios, and accounted for uncertainty in future social demands by means of three societal preference scenarios regarding SFM indicators. We found that the effects of climatic and social uncertainty on the projected performance of management were in the same order of magnitude, underlining the notion that climate change adaptation requires an integrated social-ecological perspective. Furthermore, our analysis of adaptation measures revealed considerable trade-offs between reducing adverse impacts of climate change and facilitating adaptive capacity. This finding implies that prioritization between these two general aims of adaptation is necessary in management planning, which we suggest can draw on uncertainty analysis: Where the variation induced by social-ecological uncertainty renders measures aiming to

A Comparative Survey of Adaptive Codec Solutions for VoIP over Multirate WLANs: A Capacity versus Quality Performance Trade-Off

Directory of Open Access Journals (Sweden)

Sfairopoulou A

2011-01-01

Full Text Available In multi-rate WLANs, users can suffer transmission rate changes due to the link adaptation mechanism. This results in a variable capacity channel, which is very hostile for VoIP and can cause serious quality of service (QoS degradation in all active calls. Various codec adaptation mechanisms have been proposed as a solution to this, as well as to solve congestion problems on WLAN environments. Here, these solutions are presented, categorized according to the adaptation policy and scenario they implement, and evaluated at call-level in terms of the resulting blocking and dropping probabilities, as well as the perceived voice quality. To define a common performance metric, a new index named VGoS-factor is presented, which, by combining these capacity and quality indicators, can provide an overall view of the capacity versus quality trade-off of the proposed mechanisms and consequently help in choosing the adequate policy for each scenario.

Trade-off between synergy and efficacy in combinations of HIV-1 latency-reversing agents.

Science.gov (United States)

Gupta, Vipul; Dixit, Narendra M

2018-02-01

Eradicating HIV-1 infection is difficult because of the reservoir of latently infected cells that gets established soon after infection, remains hidden from antiretroviral drugs and host immune responses, and retains the capacity to reignite infection following the cessation of treatment. Drugs called latency-reversing agents (LRAs) are being developed to reactivate latently infected cells and render them susceptible to viral cytopathicity or immune killing. Whereas individual LRAs have failed to induce adequate reactivation, pairs of LRAs have been identified recently that act synergistically and hugely increase reactivation levels compared to individual LRAs. The maximum synergy achievable with LRA pairs is of clinical importance, as it would allow latency-reversal with minimal drug exposure. Here, we employed stochastic simulations of HIV-1 transcription and translation in latently infected cells to estimate this maximum synergy. We incorporated the predominant mechanisms of action of the two most promising classes of LRAs, namely, protein kinase C agonists and histone deacetylase inhibitors, and quantified the activity of individual LRAs in the two classes by mapping our simulations to corresponding in vitro experiments. Without any adjustable parameters, our simulations then quantitatively captured experimental observations of latency-reversal when the LRAs were used in pairs. Performing simulations representing a wide range of drug concentrations, we estimated the maximum synergy achievable with these LRA pairs. Importantly, we found with all the LRA pairs we considered that concentrations yielding the maximum synergy did not yield the maximum latency-reversal. Increasing concentrations to increase latency-reversal compromised synergy, unravelling a trade-off between synergy and efficacy in LRA combinations. The maximum synergy realizable with LRA pairs would thus be restricted by the desired level of latency-reversal, a constrained optimum we elucidated with

A Composite Agent Architecture for Multi-Agent Simulations

OpenAIRE

VanPutte, Michael; Osborn, Brian; Hiles, John

2002-01-01

CGF Computer Generated Forces and Behavioral Representation The MOVES Institute’s Computer-Generated Autonomy Group has focused on a research goal of modeling complex and adaptive behavior while at the same time making the behavior easier to create and control. This research has led to several techniques for agent construction, that includes a social and organization relationship management engine, a composite agent architecture, an agent goal apparatus, a structure for capturi...

Long-Term Orientation in Trade

NARCIS (Netherlands)

Hofstede, G.J.; Jonker, C.M.; Verwaart, D.

2008-01-01

Trust does not work in the same way across cultures. This paper presents an agent model of behavior in trade across Hofstedes cultural dimension of long-term vs. short-term orientation. The situation is based on a gaming simulation, the Trust and Tracing game. The paper investigates the

Cultures of High-frequency Trading

DEFF Research Database (Denmark)

Lange, Ann-Christina; Lenglet, Marc; Seyfert, Robert

2016-01-01

As part of ongoing work to lay a foundation for social studies of high-frequency trading (HFT), this paper introduces the culture(s) of HFT as a sociological problem relating to knowledge and practice. HFT is often discussed as a purely technological development, where all that matters is the speed...... of allocating, processing and transmitting data. Indeed, the speed at which trades are executed and data transmitted is accelerating, and it is fair to say that algorithms are now the primary interacting agents operating in the financial markets. However, we contend that HFT is first and foremost a cultural...

An Agent-Based Optimization Framework for Engineered Complex Adaptive Systems with Application to Demand Response in Electricity Markets

Science.gov (United States)

Haghnevis, Moeed

The main objective of this research is to develop an integrated method to study emergent behavior and consequences of evolution and adaptation in engineered complex adaptive systems (ECASs). A multi-layer conceptual framework and modeling approach including behavioral and structural aspects is provided to describe the structure of a class of engineered complex systems and predict their future adaptive patterns. The approach allows the examination of complexity in the structure and the behavior of components as a result of their connections and in relation to their environment. This research describes and uses the major differences of natural complex adaptive systems (CASs) with artificial/engineered CASs to build a framework and platform for ECAS. While this framework focuses on the critical factors of an engineered system, it also enables one to synthetically employ engineering and mathematical models to analyze and measure complexity in such systems. In this way concepts of complex systems science are adapted to management science and system of systems engineering. In particular an integrated consumer-based optimization and agent-based modeling (ABM) platform is presented that enables managers to predict and partially control patterns of behaviors in ECASs. Demonstrated on the U.S. electricity markets, ABM is integrated with normative and subjective decision behavior recommended by the U.S. Department of Energy (DOE) and Federal Energy Regulatory Commission (FERC). The approach integrates social networks, social science, complexity theory, and diffusion theory. Furthermore, it has unique and significant contribution in exploring and representing concrete managerial insights for ECASs and offering new optimized actions and modeling paradigms in agent-based simulation.

Adaptive Neuro-Fuzzy Determination of the Effect of Experimental Parameters on Vehicle Agent Speed Relative to Vehicle Intruder.

Directory of Open Access Journals (Sweden)

Shahaboddin Shamshirband

Full Text Available Intelligent Transportation Systems rely on understanding, predicting and affecting the interactions between vehicles. The goal of this paper is to choose a small subset from the larger set so that the resulting regression model is simple, yet have good predictive ability for Vehicle agent speed relative to Vehicle intruder. The method of ANFIS (adaptive neuro fuzzy inference system was applied to the data resulting from these measurements. The ANFIS process for variable selection was implemented in order to detect the predominant variables affecting the prediction of agent speed relative to intruder. This process includes several ways to discover a subset of the total set of recorded parameters, showing good predictive capability. The ANFIS network was used to perform a variable search. Then, it was used to determine how 9 parameters (Intruder Front sensors active (boolean, Intruder Rear sensors active (boolean, Agent Front sensors active (boolean, Agent Rear sensors active (boolean, RSSI signal intensity/strength (integer, Elapsed time (in seconds, Distance between Agent and Intruder (m, Angle of Agent relative to Intruder (angle between vehicles °, Altitude difference between Agent and Intruder (m influence prediction of agent speed relative to intruder. The results indicated that distance between Vehicle agent and Vehicle intruder (m and angle of Vehicle agent relative to Vehicle Intruder (angle between vehicles ° is the most influential parameters to Vehicle agent speed relative to Vehicle intruder.

Adaptive Neuro-Fuzzy Determination of the Effect of Experimental Parameters on Vehicle Agent Speed Relative to Vehicle Intruder.

Science.gov (United States)

Shamshirband, Shahaboddin; Banjanovic-Mehmedovic, Lejla; Bosankic, Ivan; Kasapovic, Suad; Abdul Wahab, Ainuddin Wahid Bin

2016-01-01

Intelligent Transportation Systems rely on understanding, predicting and affecting the interactions between vehicles. The goal of this paper is to choose a small subset from the larger set so that the resulting regression model is simple, yet have good predictive ability for Vehicle agent speed relative to Vehicle intruder. The method of ANFIS (adaptive neuro fuzzy inference system) was applied to the data resulting from these measurements. The ANFIS process for variable selection was implemented in order to detect the predominant variables affecting the prediction of agent speed relative to intruder. This process includes several ways to discover a subset of the total set of recorded parameters, showing good predictive capability. The ANFIS network was used to perform a variable search. Then, it was used to determine how 9 parameters (Intruder Front sensors active (boolean), Intruder Rear sensors active (boolean), Agent Front sensors active (boolean), Agent Rear sensors active (boolean), RSSI signal intensity/strength (integer), Elapsed time (in seconds), Distance between Agent and Intruder (m), Angle of Agent relative to Intruder (angle between vehicles °), Altitude difference between Agent and Intruder (m)) influence prediction of agent speed relative to intruder. The results indicated that distance between Vehicle agent and Vehicle intruder (m) and angle of Vehicle agent relative to Vehicle Intruder (angle between vehicles °) is the most influential parameters to Vehicle agent speed relative to Vehicle intruder.

Farming System Evolution and Adaptive Capacity: Insights for Adaptation Support

Directory of Open Access Journals (Sweden)

Jami L. Dixon

2014-02-01

Full Text Available Studies of climate impacts on agriculture and adaptation often provide current or future assessments, ignoring the historical contexts farming systems are situated within. We investigate how historical trends have influenced farming system adaptive capacity in Uganda using data from household surveys, semi-structured interviews, focus-group discussions and observations. By comparing two farming systems, we note three major findings: (1 similar trends in farming system evolution have had differential impacts on the diversity of farming systems; (2 trends have contributed to the erosion of informal social and cultural institutions and an increasing dependence on formal institutions; and (3 trade-offs between components of adaptive capacity are made at the farm-scale, thus influencing farming system adaptive capacity. To identify the actual impacts of future climate change and variability, it is important to recognize the dynamic nature of adaptation. In practice, areas identified for further adaptation support include: shift away from one-size-fits-all approach the identification and integration of appropriate modern farming method; a greater focus on building inclusive formal and informal institutions; and a more nuanced understanding regarding the roles and decision-making processes of influential, but external, actors. More research is needed to understand farm-scale trade-offs and the resulting impacts across spatial and temporal scales.

European Trade – Where is Going? Retail Entertainment

Directory of Open Access Journals (Sweden)

Viorica JELEV

2017-12-01

Full Text Available As competition grows, brand manager imagination needs to work, and sales growth solutions need to focus on customer focus attention. It is a difficult task if all brands offer discounts in the malls they are in, and the announcement of differentiation is put to the attention of specialists who offer solutions for fun of any kind for the clients. The article aims to present the evolution of world trade in recent years and the various ways of diversion invented by retailers to keep customers in store chains longer for them to buy more. I will also present the off-line consumer profile, as found in the specialty studies and the adaptation of the entertainment methods according to these shoper typologies. The conclusion of this article will focus on what the link between entertaiment and retail is, the new concept of RETAILTAIMENT that leads to increased sales and profits of economic agents.

Fitness trade-offs in pest management and intercropping with colour: an evolutionary framework and potential application.

Science.gov (United States)

Farkas, Timothy E

2015-10-01

An important modern goal of plant science research is to develop tools for agriculturalists effective at curbing yield losses to insect herbivores, but resistance evolution continuously threatens the efficacy of pest management strategies. The high-dose/refuge strategy has been employed with some success to curb pest adaptation, and has been shown to be most effective when fitness costs (fitness trade-offs) of resistance are high. Here, I use eco-evolutionary reasoning to demonstrate the general importance of fitness trade-offs for pest control, showing that strong fitness trade-offs mitigate the threat of pest adaptation, even if adaptation were to occur. I argue that novel pest management strategies evoking strong fitness trade-offs are the most likely to persist in the face of unbridled pest adaptation, and offer the manipulation of crop colours as a worked example of one potentially effective strategy against insect herbivores.

Reliable Adaptive Data Aggregation Route Strategy for a Trade-off between Energy and Lifetime in WSNs

Directory of Open Access Journals (Sweden)

Wenzhong Guo

2014-09-01

Full Text Available Mobile security is one of the most fundamental problems in Wireless Sensor Networks (WSNs. The data transmission path will be compromised for some disabled nodes. To construct a secure and reliable network, designing an adaptive route strategy which optimizes energy consumption and network lifetime of the aggregation cost is of great importance. In this paper, we address the reliable data aggregation route problem for WSNs. Firstly, to ensure nodes work properly, we propose a data aggregation route algorithm which improves the energy efficiency in the WSN. The construction process achieved through discrete particle swarm optimization (DPSO saves node energy costs. Then, to balance the network load and establish a reliable network, an adaptive route algorithm with the minimal energy and the maximum lifetime is proposed. Since it is a non-linear constrained multi-objective optimization problem, in this paper we propose a DPSO with the multi-objective fitness function combined with the phenotype sharing function and penalty function to find available routes. Experimental results show that compared with other tree routing algorithms our algorithm can effectively reduce energy consumption and trade off energy consumption and network lifetime.

Risk-trading in flood management: An economic model.

Science.gov (United States)

Chang, Chiung Ting

2017-09-15

Although flood management is no longer exclusively a topic of engineering, flood mitigation continues to be associated with hard engineering options. Flood adaptation or the capacity to adapt to flood risk, as well as a demand for internalizing externalities caused by flood risk between regions, complicate flood management activities. Even though integrated river basin management has long been recommended to resolve the above issues, it has proven difficult to apply widely, and sometimes even to bring into existence. This article explores how internalization of externalities as well as the realization of integrated river basin management can be encouraged via the use of a market-based approach, namely a flood risk trading program. In addition to maintaining efficiency of optimal resource allocation, a flood risk trading program may also provide a more equitable distribution of benefits by facilitating decentralization. This article employs a graphical analysis to show how flood risk trading can be implemented to encourage mitigation measures that increase infiltration and storage capacity. A theoretical model is presented to demonstrate the economic conditions necessary for flood risk trading. Copyright © 2017 Elsevier Ltd. All rights reserved.

Agent and multi-Agent systems in distributed systems digital economy and e-commerce

CERN Document Server

Hartung, Ronald

2013-01-01

Information and communication technology, in particular artificial intelligence, can be used to support economy and commerce using digital means. This book is about agents and multi-agent distributed systems applied to digital economy and e-commerce to meet, improve, and overcome challenges in the digital economy and e-commerce sphere. Agent and multi-agent solutions are applied in implementing real-life, exciting developments associated with the need to eliminate problems of distributed systems.   The book presents solutions for both technology and applications, illustrating the possible uses of agents in the enterprise domain, covering design and analytic methods, needed to provide a solid foundation required for practical systems. More specifically, the book provides solutions for the digital economy, e-sourcing clusters in network economy, and knowledge exchange between agents applicable to online trading agents, and security solutions to both digital economy and e-commerce. Furthermore, it offers soluti...

An appraisal of the enzyme stability-activity trade-off.

Science.gov (United States)

Miller, Scott R

2017-07-01

A longstanding idea in evolutionary physiology is that an enzyme cannot jointly optimize performance at both high and low temperatures due to a trade-off between stability and activity. Although a stability-activity trade-off has been observed for well-characterized examples, such a trade-off is not imposed by any physical chemical constraint. To better understand the pervasiveness of this trade-off, I investigated the stability-activity relationship for comparative biochemical studies of purified orthologous enzymes identified by a literature search. The nature of this relationship varied greatly among studies. Notably, studies of enzymes with low mean synonymous nucleotide sequence divergence were less likely to exhibit the predicted negative correlation between stability and activity. Similarly, a survey of directed evolution investigations of the stability-activity relationship indicated that these traits are often uncoupled among nearly identical yet phenotypically divergent enzymes. This suggests that the presumptive trade-off often reported for investigations of enzymes with high mean sequence divergence may in some cases instead be a consequence of the degeneration over time of enzyme function in unselected environments, rather than a direct effect of thermal adaptation. The results caution against the general assertion of a stability-activity trade-off during enzyme adaptation. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.

Adaptation and mitigation: synergies and trade-offs

CSIR Research Space (South Africa)

Thambiran, Tirusha

2017-10-01

Full Text Available ) that indicates that there are many complex interactions and interdependencies between climate change impacts, adaptation and mitigation. It is increasingly recognised that decisions that are made now could lock in development trajectories for a long time... parks and tree planting along streets), which promotes adaptation to heat stress due to warming while also leading to carbon sequestration in trees and soil. A multi-species, multi-purpose approach would help reduce the vulnerability of trees...

Light-driven transformable optical agent with adaptive functions for boosting cancer surgery outcomes.

Science.gov (United States)

Qi, Ji; Chen, Chao; Zhang, Xiaoyan; Hu, Xianglong; Ji, Shenglu; Kwok, Ryan T K; Lam, Jacky W Y; Ding, Dan; Tang, Ben Zhong

2018-05-10

Fluorescence and photoacoustic imaging have different advantages in cancer diagnosis; however, combining effects in one agent normally requires a trade-off as the mechanisms interfere. Here, based on rational molecular design, we introduce a smart organic nanoparticle whose absorbed excitation energy can be photo-switched to the pathway of thermal deactivation for photoacoustic imaging, or to allow opposed routes for fluorescence imaging and photodynamic therapy. The molecule is made of a dithienylethene (DTE) core with two surrounding 2-(1-(4-(1,2,2-triphenylvinyl)phenyl)ethylidene)malononitrile (TPECM) units (DTE-TPECM). The photosensitive molecule changes from a ring-closed, for photoacoustic imaging, to a ring-opened state for fluorescence and photodynamic effects upon an external light trigger. The nanoparticles' photoacoustic and fluorescence imaging properties demonstrate the advantage of the switch. The use of the nanoparticles improves the outcomes of in vivo cancer surgery using preoperative photoacoustic imaging and intraoperative fluorescent visualization/photodynamic therapy of residual tumours to ensure total tumour removal.

Trade and climate change

Energy Technology Data Exchange (ETDEWEB)

Tamiotti, L.; Teh, R.; Kulacoglu, V. (World Trade Organization (WTO), Geneva (Switzerland)); Olhoff, A.; Simmons, B.; Abaza, H. (United Nations Environment Programme (UNEP) (Denmark))

2009-06-15

The Report aims to improve understanding about the linkages between trade and climate change. It shows that trade intersects with climate change in a multitude of ways. For example, governments may introduce a variety of policies, such as regulatory measures and economic incentives, to address climate change. This complex web of measures may have an impact on international trade and the multilateral trading system. The Report begins with a summary of the current state of scientific knowledge on climate change and on the options available for responding to the challenge of climate change. The scientific review is followed by a part on the economic aspects of the link between trade and climate change, and these two parts set the context for the subsequent parts of the Report, which looks at the policies introduced at both the international and national level to address climate change. The part on international policy responses to climate change describes multilateral efforts to reduce greenhouse gas emissions and to adapt to the effects of climate change, and also discusses the role of the current trade and environment negotiations in promoting trade in technologies that aim to mitigate climate change. The final part of the Report gives an overview of a range of national policies and measures that have been used in a number of countries to reduce greenhouse gas emissions and to increase energy efficiency. It presents key features in the design and implementation of these policies, in order to draw a clearer picture of their overall effect and potential impact on environmental protection, sustainable development and trade. It also gives, where appropriate, an overview of the WTO rules that may be relevant to such measures. (author)

A Cross-Cultural Multi-agent Model of Opportunism in Trade

NARCIS (Netherlands)

Hofstede, G.J.; Jonker, C.M.; Verwaart, D.

2010-01-01

According to transaction cost economics, contracts are always incomplete and offer opportunities to defect. Some level of trust is a sine qua non for trade. If the seller is better informed about product quality than the buyer, the buyer has to rely on information the seller provides or has to check

EXISTENCE OF TRADITIONAL FORMATS AND SELF SERVICE IN RETAIL TRADE

Directory of Open Access Journals (Sweden)

Betzaida Oliveros de Sarmiento

2015-04-01

Full Text Available Research determines the concept of store format; revises the definition of each format and trade strategy which characterizes it as a result of adaptation to the type of consumer who is headed. There are commercial sectors in Venezuela where the traditional and self-formats coexist due to the adaptation of each store to your target consumer; this process must be continued to ensure the sustainability of the shop in the market. It is suggested that there are numerous alternatives for future research to determine the success of different formats in specific sectors of Venezuelan retail trade.

Bidding Strategies in Agent-based Continuous Double Auctions

NARCIS (Netherlands)

H. Ma (Huiye); H.-F. Leung

2008-01-01

htmlabstractOnline auctions are a platform to trade goods on the Internet. In this context, negotiation capabilities for software agents in continuous double auctions (CDAs) are a central concern. Agents need to be able to prepare bids for and evaluate offers on behalf of the users they represent

Five essays on emissions trading

Energy Technology Data Exchange (ETDEWEB)

Godal, Odd

2005-03-01

The thesis discusses energy, environmental and economic aspects of polluting emissions with emphasis on greenhouse gas trade and political measures. 5 papers are included with titles: 1) Carbon trading across sources and periods constrained by the Marrakesh Accords which examines examine the potential effects on permit prices and abatement costs of four compliance rules governing emissions trade across sources and periods in the Kyoto Protocol: The banking rule that allows excess permits to be used later; the restoration rate rule that penalizes borrowing; the commitment period reserve rule that limits sales; and finally, the suspension rule that restricts borrowing and sales. Our framework is a two-period model where parties may be out of compliance in the Kyoto period, but are assumed to comply at a later time. Under varying assumptions about market power and US participation, we find that the rules may have pronounced effects on individual costs, but overall efficiency is not severely affected. 2) Affine price expectations and equilibrium in strategic markets which considers equilibrium in imperfect markets, featuring agents who exchange property rights. Important cases include trade in emission permits of greenhouse gases, or exchange of catch quotas of fish. Some players act strategically while others are price-takers. The ''demand curve'' is endogenous, and it affects all parties. The resulting, reduced objectives need not be concave. Therefore, existence of equilibrium is a delicate matter. To simplify things, and to ensure availability of ''equilibria up to first order'', we presume that all strategic agents form affine price expectations. 3) Greenhouse gases, quota exchange and oligopolistic competition that discusses the problem how quotas can be shared in the ''emissions market'' and how can the agents reach as overall equilibrium in the product market. 4) Strategic markets in property rights

Five essays on emissions trading

Energy Technology Data Exchange (ETDEWEB)

Godal, Odd

2005-03-01

The thesis discusses energy, environmental and economic aspects of polluting emissions with emphasis on greenhouse gas trade and political measures. 5 papers are included with titles: 1) Carbon trading across sources and periods constrained by the Marrakesh Accords which examines examine the potential effects on permit prices and abatement costs of four compliance rules governing emissions trade across sources and periods in the Kyoto Protocol: The banking rule that allows excess permits to be used later; the restoration rate rule that penalizes borrowing; the commitment period reserve rule that limits sales; and finally, the suspension rule that restricts borrowing and sales. Our framework is a two-period model where parties may be out of compliance in the Kyoto period, but are assumed to comply at a later time. Under varying assumptions about market power and US participation, we find that the rules may have pronounced effects on individual costs, but overall efficiency is not severely affected. 2) Affine price expectations and equilibrium in strategic markets which considers equilibrium in imperfect markets, featuring agents who exchange property rights. Important cases include trade in emission permits of greenhouse gases, or exchange of catch quotas of fish. Some players act strategically while others are price-takers. The ''demand curve'' is endogenous, and it affects all parties. The resulting, reduced objectives need not be concave. Therefore, existence of equilibrium is a delicate matter. To simplify things, and to ensure availability of ''equilibria up to first order'', we presume that all strategic agents form affine price expectations. 3) Greenhouse gases, quota exchange and oligopolistic competition that discusses the problem how quotas can be shared in the ''emissions market'' and how can the agents reach as overall equilibrium in the product market. 4) Strategic markets in property rights without price-takers that deals with Cournot-type models of

Resilience through adaptation

NARCIS (Netherlands)

Broeke, ten Guus; Voorn, van George A.K.; Ligtenberg, Arend; Molenaar, Jaap

2017-01-01

Adaptation of agents through learning or evolution is an important component of the resilience of Complex Adaptive Systems (CAS). Without adaptation, the flexibility of such systems to cope with outside pressures would be much lower. To study the capabilities of CAS to adapt, social simulations

Adaptive response to DNA-damaging agents in natural Saccharomyces cerevisiae populations from "Evolution Canyon", Mt. Carmel, Israel.

Directory of Open Access Journals (Sweden)

Gabriel A Lidzbarsky

2009-06-01

Full Text Available Natural populations of most organisms, especially unicellular microorganisms, are constantly exposed to harsh environmental factors which affect their growth. UV radiation is one of the most important physical parameters which influences yeast growth in nature. Here we used 46 natural strains of Saccharomyces cerevisiae isolated from several natural populations at the "Evolution Canyon" microsite (Nahal Oren, Mt. Carmel, Israel. The opposing slopes of this canyon share the same geology, soil, and macroclimate, but they differ in microclimatic conditions. The interslope differences in solar radiation (200%-800% more on the "African" slope caused the development of two distinct biomes. The south-facing slope is sunnier and has xeric, savannoid "African" environment while the north-facing slope is represented by temperate, "European" forested environment. Here we studied the phenotypic response of the S. cerevisiae strains to UVA and UVC radiations and to methyl methanesulfonate (MMS in order to evaluate the interslope effect on the strains' ability to withstand DNA-damaging agents.We exposed our strains to the different DNA-damaging agents and measured survival by counting colony forming units. The strains from the "African" slope were more resilient to both UVA and MMS than the strains from the "European" slope. In contrast, we found that there was almost no difference between strains (with similar ploidy from the opposite slopes, in their sensitivity to UVC radiation. These results suggest that the "African" strains are more adapted to higher solar radiation than the "European" strains. We also found that the tetraploids strains were more tolerant to all DNA-damaging agents than their neighboring diploid strains, which suggest that high ploidy level might be a mechanism of adaptation to high solar radiation.Our results and the results of parallel studies with several other organisms, suggest that natural selection appears to select, at a

Mathematical modeling of malaria infection with innate and adaptive immunity in individuals and agent-based communities.

Science.gov (United States)

Gurarie, David; Karl, Stephan; Zimmerman, Peter A; King, Charles H; St Pierre, Timothy G; Davis, Timothy M E

2012-01-01

Agent-based modeling of Plasmodium falciparum infection offers an attractive alternative to the conventional Ross-Macdonald methodology, as it allows simulation of heterogeneous communities subjected to realistic transmission (inoculation patterns). We developed a new, agent based model that accounts for the essential in-host processes: parasite replication and its regulation by innate and adaptive immunity. The model also incorporates a simplified version of antigenic variation by Plasmodium falciparum. We calibrated the model using data from malaria-therapy (MT) studies, and developed a novel calibration procedure that accounts for a deterministic and a pseudo-random component in the observed parasite density patterns. Using the parasite density patterns of 122 MT patients, we generated a large number of calibrated parameters. The resulting data set served as a basis for constructing and simulating heterogeneous agent-based (AB) communities of MT-like hosts. We conducted several numerical experiments subjecting AB communities to realistic inoculation patterns reported from previous field studies, and compared the model output to the observed malaria prevalence in the field. There was overall consistency, supporting the potential of this agent-based methodology to represent transmission in realistic communities. Our approach represents a novel, convenient and versatile method to model Plasmodium falciparum infection.

Mathematical modeling of malaria infection with innate and adaptive immunity in individuals and agent-based communities.

Directory of Open Access Journals (Sweden)

David Gurarie

Full Text Available BACKGROUND: Agent-based modeling of Plasmodium falciparum infection offers an attractive alternative to the conventional Ross-Macdonald methodology, as it allows simulation of heterogeneous communities subjected to realistic transmission (inoculation patterns. METHODOLOGY/PRINCIPAL FINDINGS: We developed a new, agent based model that accounts for the essential in-host processes: parasite replication and its regulation by innate and adaptive immunity. The model also incorporates a simplified version of antigenic variation by Plasmodium falciparum. We calibrated the model using data from malaria-therapy (MT studies, and developed a novel calibration procedure that accounts for a deterministic and a pseudo-random component in the observed parasite density patterns. Using the parasite density patterns of 122 MT patients, we generated a large number of calibrated parameters. The resulting data set served as a basis for constructing and simulating heterogeneous agent-based (AB communities of MT-like hosts. We conducted several numerical experiments subjecting AB communities to realistic inoculation patterns reported from previous field studies, and compared the model output to the observed malaria prevalence in the field. There was overall consistency, supporting the potential of this agent-based methodology to represent transmission in realistic communities. CONCLUSIONS/SIGNIFICANCE: Our approach represents a novel, convenient and versatile method to model Plasmodium falciparum infection.

Buying on margin, selling short in an agent-based market model

Science.gov (United States)

Zhang, Ting; Li, Honggang

2013-09-01

Credit trading, or leverage trading, which includes buying on margin and selling short, plays an important role in financial markets, where agents tend to increase their leverages for increased profits. This paper presents an agent-based asset market model to study the effect of the permissive leverage level on traders’ wealth and overall market indicators. In this model, heterogeneous agents can assume fundamental value-converging expectations or trend-persistence expectations, and their effective demands of assets depend both on demand willingness and wealth constraints, where leverage can relieve the wealth constraints to some extent. The asset market price is determined by a market maker, who watches the market excess demand, and is influenced by noise factors. By simulations, we examine market results for different leverage ratios. At the individual level, we focus on how the leverage ratio influences agents’ wealth accumulation. At the market level, we focus on how the leverage ratio influences changes in the asset price, volatility, and trading volume. Qualitatively, our model provides some meaningful results supported by empirical facts. More importantly, we find a continuous phase transition as we increase the leverage threshold, which may provide a further prospective of credit trading.

The impact of Romanian adhesion to European Union on exterior trade

OpenAIRE

Craciunas, Diana

2009-01-01

Analysis of the Romanian external trade policies in European integration context underlining the external trade policy of Romania which according with European Union policies after the joining to the European Union, the improvement and adaptation of external trade policy to the European standards through internal and external measures and the commercial effect of the extensions of the European Union over non member countries of Europe and on the European Union position in the international co...

Trading strategies modeling in Colombian power market using artificial intelligence techniques

International Nuclear Information System (INIS)

Moreno, Julian

2009-01-01

The aim of this paper is to present a model based on fuzzy logic and machine learning in order to maximize the profits of Colombian energy trade agents according to their risk profile. The model has two parts, the first one is a fuzzy expert system that gives a recommendation about the trade strategy these agents should follow, and whose definition depends mainly on market conditions. The second one is a reinforced learning mechanism with which the agents 'learn' when they perceive the consequences of their actions, so they modify such actions looking for a reward not just in short but also in long-term. The whole model is validated using actual data as well as a simulation approach using synthetic time series for some relevant variables as hydraulic availability, energy pool price and bilateral contracts price. (author)

Trading strategies modeling in Colombian power market using artificial intelligence techniques

Energy Technology Data Exchange (ETDEWEB)

Moreno, Julian [Escuela de Sistemas, Universidad Nacional de Colombia, Carrera 80 No. 65-223 Bloque M8A Medellin (Colombia)

2009-03-15

The aim of this paper is to present a model based on fuzzy logic and machine learning in order to maximize the profits of Colombian energy trade agents according to their risk profile. The model has two parts, the first one is a fuzzy expert system that gives a recommendation about the trade strategy these agents should follow, and whose definition depends mainly on market conditions. The second one is a reinforced learning mechanism with which the agents 'learn' when they perceive the consequences of their actions, so they modify such actions looking for a reward not just in short but also in long-term. The whole model is validated using actual data as well as a simulation approach using synthetic time series for some relevant variables as hydraulic availability, energy pool price and bilateral contracts price. (author)

Permit trading and credit trading

DEFF Research Database (Denmark)

Boom, Jan-Tjeerd; R. Dijstra, Bouwe

This paper compares emissions trading based on a cap on total emissions (permit trading) and on relative standards per unit of output (credit trading). Two types of market structure are considered: perfect competition and Cournot oligopoly. We find that output, abatement costs and the number...... of firms are higher under credit trading. Allowing trade between permit-trading and credit-trading sectors may increase in welfare. With perfect competition, permit trading always leads to higher welfare than credit trading. With imperfect competition, credit trading may outperform permit trading....... Environmental policy can lead to exit, but also to entry of firms. Entry and exit have a profound impact on the performance of the schemes, especially under imperfect competition. We find that it may be impossible to implement certain levels of total industry emissions. Under credit trading several levels...

Towards informed and multi-faceted wildlife trade interventions

Directory of Open Access Journals (Sweden)

Daniel W.S. Challender

2015-01-01

Full Text Available International trade in wildlife is a key threat to biodiversity conservation. CITES, the Convention on International Trade in Endangered Species of Wild Fauna and Flora, seeks to ensure international wildlife trade is sustainable, relying on trade bans and controls. However, there has been little comprehensive review of its effectiveness and here we review approaches taken to regulate wildlife trade in CITES. Although assessing its effectiveness is problematic, we assert that CITES boasts few measurable conservation successes. We attribute this to: non-compliance, an over reliance on regulation, lack of knowledge and monitoring of listed species, ignorance of market forces, and influence among CITES actors. To more effectively manage trade we argue that interventions should go beyond regulation and should be multi-faceted, reflecting the complexity of wildlife trade. To inform these interventions we assert an intensive research effort is needed around six key areas: (1 factors undermining wildlife trade governance at the national level, (2 determining sustainable harvest rates for, and adaptive management of CITES species, (3 gaining the buy-in of local communities in implementing CITES, (4 supply and demand based market interventions, (5 means of quantifying illicit trade, and (6 political processes and influence within CITES.

20 CFR 404.1069 - Real estate agents and direct sellers.

Science.gov (United States)

2010-04-01

... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false Real estate agents and direct sellers. 404... § 404.1069 Real estate agents and direct sellers. (a) Trade or business. If you perform services after 1982 as a qualified real estate agent or as a direct seller, as defined in section 3508 of the Code...

Multi-agent adaptive systems in dry bulk shipping

NARCIS (Netherlands)

Engelen, Steve; Dullaert, Wout; Vernimmen, Bert

Investment decisions in dry bulk shipping form one of the most difficult managerial tasks due to the high degree of uncertainty and the cyclical nature of the market. Adequate information on ship prices is, therefore, crucial when justifying such decisions. This paper is the first to embed trading

Parameter extraction of different fuel cell models with transferred adaptive differential evolution

International Nuclear Information System (INIS)

Gong, Wenyin; Yan, Xuesong; Liu, Xiaobo; Cai, Zhihua

2015-01-01

To improve the design and control of FC (fuel cell) models, it is important to extract their unknown parameters. Generally, the parameter extraction problems of FC models can be transformed as nonlinear and multi-variable optimization problems. To extract the parameters of different FC models exactly and fast, in this paper, we propose a transferred adaptive DE (differential evolution) framework, in which the successful parameters of the adaptive DE solving previous problems are properly transferred to solve new optimization problems in the similar problem-domains. Based on this framework, an improved adaptive DE method (TRADE, in short) is presented as an illustration. To verify the performance of our proposal, TRADE is used to extract the unknown parameters of two types of fuel cell models, i.e., PEMFC (proton exchange membrane fuel cell) and SOFC (solid oxide fuel cell). The results of TRADE are also compared with those of other state-of-the-art EAs (evolutionary algorithms). Even though the modification is very simple, the results indicate that TRADE can extract the parameters of both PEMFC and SOFC models exactly and fast. Moreover, the V–I characteristics obtained by TRADE agree well with the simulated and experimental data in all cases for both types of fuel cell models. Also, it improves the performance of the original adaptive DE significantly in terms of both the quality of final solutions and the convergence speed in all cases. Additionally, TRADE is able to provide better results compared with other EAs. - Highlights: • A framework of transferred adaptive differential evolution is proposed. • Based on the framework, an improved differential evolution (TRADE) is presented. • TRADE obtains very promising results to extract the parameters of PEMFC and SOFC models

Constraints, Trade-offs and the Currency of Fitness.

Science.gov (United States)

Acerenza, Luis

2016-03-01

Understanding evolutionary trajectories remains a difficult task. This is because natural evolutionary processes are simultaneously affected by various types of constraints acting at the different levels of biological organization. Of particular importance are constraints where correlated changes occur in opposite directions, called trade-offs. Here we review and classify the main evolutionary constraints and trade-offs, operating at all levels of trait hierarchy. Special attention is given to life history trade-offs and the conflict between the survival and reproduction components of fitness. Cellular mechanisms underlying fitness trade-offs are described. At the metabolic level, a linear trade-off between growth and flux variability was found, employing bacterial genome-scale metabolic reconstructions. Its analysis indicates that flux variability can be considered as the currency of fitness. This currency is used for fitness transfer between fitness components during adaptations. Finally, a discussion is made regarding the constraints which limit the increase in the amount of fitness currency during evolution, suggesting that occupancy constraints are probably the main restrictions.

Executive Compensation and Principal-Agent Theory.

OpenAIRE

Garen, John E

1994-01-01

The empirical literature on executive compensation generally fails to specify a model of executive pay on which to base hypotheses regarding its determinants. In contrast, this paper analyzes a simple principal-agent model to determine how well it explains variations in CEO incentive pay and salaries. Many findings are consistent with the basic intuition of principle-agent models that compensation is structured to trade off incentives with insurance. However, statistical significance for some...

78 FR 21045 - Adaptation of Regulations to Incorporate Swaps-Records of Transactions; Correction

Science.gov (United States)

2013-04-09

... COMMODITY FUTURES TRADING COMMISSION 17 CFR Part 1 RIN 3038-AD53 Adaptation of Regulations to Incorporate Swaps--Records of Transactions; Correction AGENCY: Commodity Futures Trading Commission. ACTION...), regarding Adaptation of Regulations to Incorporate Swaps--Records of Transactions. DATES: This correction to...

Globalization, Trade and Poverty in Ghana | IDRC - International ...

International Development Research Centre (IDRC) Digital Library (Canada)

2012-01-01

Jan 1, 2012 ... ... debate on the impact of globalization, in general, and trade liberalization, in particular, on poverty. ... Maternal health research concerns men too ... IDRC and key partners will showcase critical work on adaptation and ...

Systematizing the Instruments of Trade Wars and of Concealed Protectionism

Directory of Open Access Journals (Sweden)

Serpukhov Maksym Yu.

2017-11-01

Full Text Available The article is concerned with the problems of trade wars and hidden protectionism in the process of implementing international trade. The main purpose of the research is systematization of trade barriers and instruments used in the trade wars between countries. The basic instruments of trade wars have been analyzed, a list of the key instruments used in the trade wars between countries has been defined, and also the possible influence of these instruments has been described. The statistical analysis has resulted in identifying the main trade barriers and the most popular sectors of the economy in which protectionism instruments are applied. The authors have also defined the main interventions applied by different world countries in relation to Ukrainian products and groups of Ukrainian goods to which the most restrictions by the world countries are applied. The conclusions on counteraction and adaptation to the most popular instruments of protectionism in the process of activation of the export activity of country have been generalized.

A Cross-Cultural Study of Reference Point Adaptation: Evidence from China, Korea, and the US

Science.gov (United States)

Arkes, Hal R.; Hirshleifer, David; Jiang, Danling; Lim, Sonya S.

2010-01-01

We examined reference point adaptation following gains or losses in security trading using participants from China, Korea, and the US. In both questionnaire studies and trading experiments with real money incentives, reference point adaptation was larger for Asians than for Americans. Subjects in all countries adapted their reference points more…

Molecular mechanisms of adaptive response to alkylating agents in Escherichia coli and some remarks on O(6)-methylguanine DNA-methyltransferase in other organisms.

Science.gov (United States)

Kleibl, Karol

2002-09-01

Alkylating agents are environmental genotoxic agents with mutagenic and carcinogenic potential, however, their properties are also exploited in the treatment of malignant diseases. O(6)-Methylguanine is an important adduct formed by methylating agents that, if not repaired, can lead to mutations and death. Its repair is carried out by O(6)-methylguanine DNA-methyltransferase (MTase) in an unique reaction in which methyl groups are transferred to the cysteine acceptor site of the protein itself. Exposure of Escherichia coli cells to sublethal concentrations of methylating agents triggers the expression of a set of genes, which allows the cells to tolerate DNA lesions, and this kind of inducible repair is called the adaptive response. The MTase of E. coli, encoded by the ada gene was the first MTase to be discovered and one of best characterised. Its repair and regulatory mechanisms are understood in considerable detail and this bacterial protein played a key role in identification of its counterparts in other living organisms. This review summarises the nature of alkylation damage in DNA and our current knowledge about the adaptive response in E. coli. I also include a brief mention of MTases from other organisms with the emphasis on the human MTase, which could play a crucial role in both cancer prevention and cancer treatment.

Self-organization in a simple model of adaptive agents playing 2 x 2 games with arbitrary payoff matrices.

Science.gov (United States)

Fort, H; Viola, S

2004-03-01

We analyze, both analytically and numerically, the self-organization of a system of "selfish" adaptive agents playing an arbitrary iterated pairwise game (defined by a 2 x 2 payoff matrix). Examples of possible games to play are the prisoner's dilemma (PD) game, the chicken game, the hero game, etc. The agents have no memory, use strategies not based on direct reciprocity nor "tags" and are chosen at random, i.e., geographical vicinity is neglected. They can play two possible strategies: cooperate (C) or defect (D). The players measure their success by comparing their utilities with an estimate for the expected benefits and update their strategy following a simple rule. Two versions of the model are studied: (1) the deterministic version (the agents are either in definite states C or D) and (2) the stochastic version (the agents have a probability c of playing C). Using a general master equation we compute the equilibrium states into which the system self-organizes, characterized by their average probability of cooperation c(eq). Depending on the payoff matrix, we show that c(eq) can take five different values. We also consider the mixing of agents using two different payoff matrices and show that any value of c(eq) can be reached by tuning the proportions of agents using each payoff matrix. In particular, this can be used as a way to simulate the effect of a fraction d of "antisocial" individuals--incapable of realizing any value to cooperation--on the cooperative regime hold by a population of neutral or "normal" agents.

A Multilateral Negotiation Model for Cloud Service Market

Science.gov (United States)

Yoo, Dongjin; Sim, Kwang Mong

Trading cloud services between consumers and providers is a complicated issue of cloud computing. Since a consumer can negotiate with multiple providers to acquire the same service and each provider can receive many requests from multiple consumers, to facilitate the trading of cloud services among multiple consumers and providers, a multilateral negotiation model for cloud market is necessary. The contribution of this work is the proposal of a business model supporting a multilateral price negotiation for trading cloud services. The design of proposed systems for cloud service market includes considering a many-to-many negotiation protocol, and price determining factor from service level feature. Two negotiation strategies are implemented: 1) MDA (Market Driven Agent); and 2) adaptive concession making responding to changes of bargaining position are proposed for cloud service market. Empirical results shows that MDA achieved better performance in some cases that the adaptive concession making strategy, it is noted that unlike the MDA, the adaptive concession making strategy does not assume that an agent has information of the number of competitors (e.g., a consumer agent adopting the adaptive concession making strategy need not know the number of consumer agents competing for the same service).

Manual for the energy trade. 3. new rev. and enl. ed.

International Nuclear Information System (INIS)

Schwintowski, Hans-Peter

2014-01-01

This manual sheds a light on the energy trade from both a legal and an empirical economic perspective. Its focus is on those business fields within the energy trade that are of foremost practical relevance, namely the OTC trade and the exchange trade. It also provides concise coverage of risk management systems in the energy trade along with a competent account of their implications with regard to supervisory regulations. In this, its third edition the manual addresses the latest developments in both the national and the international energy trade, including those seen in the gas storage market and its market access regulations; consideration is here also given to market transparency, market distortion and liquidity. The commentary on standard contracts (EFET) has been updated. The manual also addresses the adaptations made in the minimum requirements for risk management.

75 FR 1345 - Solicitation of Applications for the Community Trade Adjustment Assistance Program

Science.gov (United States)

2010-01-11

... communities respond to the loss of jobs caused by the layoffs at firms and other types of employers impacted..., planning, and infrastructure projects to help communities adapt to pressing trade impact issues and... the following three Trade Adjustment Assistance (TAA) programs: TAA for Workers, TAA for Firms, or TAA...

A MultiAgent Architecture for Collaborative Serious Game applied to Crisis Management Training: Improving Adaptability of Non Player Characters

Directory of Open Access Journals (Sweden)

M’hammed Ali Oulhaci

2014-05-01

Full Text Available Serious Games (SG are more and more used for training, as in the crisis management domain, where several hundred stakeholders can be involved, causing various organizational difficulties on field exercises. SGs specific benefits include player immersion and detailed players’ actions tracking during a virtual exercise. Moreover, Non Player Characters (NPC can adapt the crisis management exercise perimeter to the available stakeholders or to specific training objectives. In this paper we present a Multi-Agent System architecture supporting behavioural simulation as well as monitoring and assessment of human players. A NPC is enacted by a Game Agent which reproduces the behaviour of a human actor, based on a deliberative model (Belief Desire Intention. To facilitate the scenario design, an Agent editor allows a designer to configure agents’behaviours. The behaviour simulation was implemented within the pre-existing SIMFOR project, a serious game for training in crisis management.

Terms of trade and Russian economic development

Directory of Open Access Journals (Sweden)

Georgy Idrisov

2016-09-01

Full Text Available The paper discusses economic development trends in Russia in late 2014 and 2015 and reviews the basic mechanisms of how changes in the terms of trade affect the economic development of countries from a historical perspective and with a particular focus on those changes in the Russian economy that occurred in late 2014 and 2015. The authors demonstrate that structural reforms aimed at diversification of production and exports are necessary for sustainable economic development, for social stability and for reducing the impact of variability in the terms of trade on the Russian economy. During periods of instability in the government agenda's measures for the real and financial sectors, it is necessary not only to compensate economic agents losses caused by changes in the terms of trade but also to improve the economic structure and to develop and enhance the stability of the financial markets.

Computational Intelligence Agent-Oriented Modelling

Czech Academy of Sciences Publication Activity Database

Neruda, Roman

2006-01-01

Roč. 5, č. 2 (2006), s. 430-433 ISSN 1109-2777 R&D Projects: GA MŠk 1M0567 Institutional research plan: CEZ:AV0Z10300504 Keywords : multi-agent systems * adaptive agents * computational intelligence Subject RIV: IN - Informatics, Computer Science

Driving Meaningful Adaptation Action through an Adaptation Market Mechanism

Energy Technology Data Exchange (ETDEWEB)

Butzengeiger-Geyer, Sonja; Koehler, Michel; Michaelowa, Axel

2011-07-01

Approaches and criteria for allocating adaptation funds vary significantly among current sources - UN-backed funds and bilateral cooperation - and to some extent lack transparency and consistency. Such funding risks being spent in a haphazard way that repeats many of the mistakes made in development assistance over the past decades. An Adaptation Market Mechanism (AMM) could contribute to efficient allocation of adaptation funds, promote adaptation activities by private and public actors through additional financial incentives, and raise additional and reliable adaptation money. This would help to avoid future public criticism of the effectiveness and efficiency of spending adaptation funding.The proposed AMM would specify mandatory adaptation targets, on international, regional or domestic level. Participants who achieve their targets either by generating adaptation units or by buying them in the market would incentivize private, commercial and institutional actors to develop adaptation projects that create verified adaptation units. A universally accepted and verifiable trading unit applicable to all types of adaptation activities would help to maximize the cost reduction potential for the AMM. We suggest applying net present value (NPV) for property saved; Disability Adjusted Life Years Saved (DALYS) for health benefits; and potentially a separate unit to consider the environmental benefits of an adaptation activity.(Author)

Trade networks evolution under the conditions of stock market globalization

Directory of Open Access Journals (Sweden)

Kopylova Olga Volodymyrivna

2016-12-01

Full Text Available The modern perception of the stock market in terms of information technologies rapid development and under the institutionalists influence has been significantly modified and becomes multifaceted. It was detected that the main function of the market is activated, information asymmetry is minimized and more advanced financial architecture space is formed through trade networks. Formation of the modern trade networks has started on the basis of the old infrastructure, that had the highest tendency to self-organization and adaptation. The proposed architecture of trade networks of the stock market has a very clear vector of subordination – from top to bottom and has a number of positive points.

Emission trading in Europe with an exchange rate

International Nuclear Information System (INIS)

Klassen, G.A.J.; Amann, M.; Foersund, F.R.

1994-01-01

The analytical and empirical properties of a new method for emission trading according to a fixed exchange rate are explored. The exchange rate is based on the ratios of the marginal costs of abatement in the optimal solution in order to account for the impact of the location of emission sources on the deposition. It is shown that, generally, this system will not achieve the optimal solution and does not guarantee that environmental deposition constraints are not violated, although total abatement costs are always reduced. A routine was developed to mimic trading as a bilateral, sequential process, subject to an exchange rate. Use has been made of an adapted version of the optimization module in the RAINS (REgional Acidification INformation and Simulation) model. In the example used, results for SO 2 emissions in Europe show that, starting from a uniform reduction, exchange-rate trading achieves higher cost savings than one-to-one trading, without achieving the cost minimum. Sulfur deposition targets are not violated since the initial emission allocation overfulfilled targets at many places. The results are sensitive to: pre-trade emission levels, the transaction costs, the availability of information on potential cost savings and assumptions made on the behavior of trading partners. 6 figs., 3 tabs., 28 refs

Emission trading scheme: market analysis and forecasting scenarios

International Nuclear Information System (INIS)

Clo, Stefano

2006-01-01

This article offers an economic analysis of the Emission Trading Scheme (ETS) and its institutional framework; we introduce an economic model able to simulate some possible market price's scenarios. The aim of this article is to offer a better market fundamentals' comprehension and to help economic agents building their expectations about market's development [it

78 FR 14979 - Trade Mission to Egypt and Kuwait

Science.gov (United States)

2013-03-08

... appointments with pre-screened potential buyers, agents, distributors and joint venture partners; meetings with... for one representative to participate in the mission is $1400 for an SME and $2100 for large firms or trade associations. The fee for each additional company or association representative (SME or large firm...

Trade-offs between developmental parameters of two endoparasitoids developing in different instars of the same host species

NARCIS (Netherlands)

Malčická, Mima; Harvey, J.A.

2014-01-01

Trade-offs amongst life history traits is a major theme in evolutionary biology. Parasitoid wasps are important biological control agents and make excellent organisms to examine trade-offs in fitness related traits such as size, development rate and survival. Here, we examined trait-related

Impacts of licensed premises trading hour policies on alcohol-related harms.

Science.gov (United States)

Atkinson, Jo-An; Prodan, Ante; Livingston, Michael; Knowles, Dylan; O'Donnell, Eloise; Room, Robin; Indig, Devon; Page, Andrew; McDonnell, Geoff; Wiggers, John

2018-07-01

Evaluations of alcohol policy changes demonstrate that restriction of trading hours of both 'on'- and 'off'-licence venues can be an effective means of reducing rates of alcohol-related harm. Despite this, the effects of different trading hour policy options over time, accounting for different contexts and demographic characteristics, and the common co-occurrence of other harm reduction strategies in trading hour policy initiatives, are difficult to estimate. The aim of this study was to use dynamic simulation modelling to compare estimated impacts over time of a range of trading hour policy options on various indicators of acute alcohol-related harm. An agent-based model of alcohol consumption in New South Wales, Australia was developed using existing research evidence, analysis of available data and a structured approach to incorporating expert opinion. Five policy scenarios were simulated, including restrictions to trading hours of on-licence venues and extensions to trading hours of bottle shops. The impact of the scenarios on four measures of alcohol-related harm were considered: total acute harms, alcohol-related violence, emergency department (ED) presentations and hospitalizations. Simulation of a 3 a.m. (rather than 5 a.m.) closing time resulted in an estimated 12.3 ± 2.4% reduction in total acute alcohol-related harms, a 7.9 ± 0.8% reduction in violence, an 11.9 ± 2.1% reduction in ED presentations and a 9.5 ± 1.8% reduction in hospitalizations. Further reductions were achieved simulating a 1 a.m. closing time, including a 17.5 ± 1.1% reduction in alcohol-related violence. Simulated extensions to bottle shop trading hours resulted in increases in rates of all four measures of harm, although most of the effects came from increasing operating hours from 10 p.m. to 11 p.m. An agent-based simulation model suggests that restricting trading hours of licensed venues reduces rates of alcohol-related harm and extending trading hours of bottle

Dynamics of a durable commodity market involving trade at disequilibrium

Science.gov (United States)

Panchuk, A.; Puu, T.

2018-05-01

The present work considers a simple model of a durable commodity market involving two agents who trade stocks of two different types. Stock commodities, in contrast to flow commodities, remain on the market from period to period and, consequently, there is neither unique demand function nor unique supply function exists. We also set up exact conditions for trade at disequilibrium, the issue being usually neglected, though a fact of reality. The induced iterative system has infinite number of fixed points and path dependent dynamics. We show that a typical orbit is either attracted to one of the fixed points or eventually sticks at a no-trade point. For the latter the stock distribution always remains the same while the price displays periodic or chaotic oscillations.

Quantifying Third-Party Impacts and Environmental Externalities from a Cap-And-Trade System for Groundwater Management

Science.gov (United States)

Khan, H. F.; Yang, Y. C. E.; Brown, C.

2016-12-01

Economic decision models, such as the cap-and-trade system, have been shown to be useful in the context of groundwater management. A uniformly applied cap-and-trade system can however result in significant spatially and temporally varying hydrogeologic impacts that reduce public welfare. Hydrological challenges associated with the cap-and-trade system for groundwater management include establishing appropriate system boundaries, setting system-wide sustainable yield and limiting third party impacts from extractions. Given these challenges, these economic models need to be supplemented with physically based hydrogeologic models that are able to represent the spatial and temporal heterogeneity in conditions across a region. This investigation assesses third-party impacts and environmental externalities resulting from a cap-and-trade system in a sub-basin of the Republican River Basin, overlying the Ogallala aquifer in the High Plains of the United States. The economic model is coupled with a calibrated physically based groundwater model. The cap-and-trade system is developed using a multi-agent system model where individual benefits of each self-interested agent are maximized subject to bounds on irrigation requirements and water use permits. We then compare the performance of the cap-and-trade system with a smart groundwater market which, in addition to a cap on total groundwater extraction, also incorporates streamflow constraints. The results quantify third-party impacts and environmental externalities resulting from uncontrolled trading. This analysis demonstrates the value added by a well-designed cap-and-trade system able to account for basin-wide heterogeneity in hydrogeologic and ecological conditions by establishing trading limits, managing inter-area transfers and setting exchange rates for permit trading.

EU emissions trading. The need for cap adjustment in response to external shocks and unexpected developments?

Energy Technology Data Exchange (ETDEWEB)

Diekmann, Jochen [DIW, Berlin (Germany)

2012-11-15

In this paper the advantages and disadvantages of the various adaptation options will be discussed from an economic perspective. Firstly, the criteria for identifying a need for potentially legitimate adaptation should be investigated. Furthermore, the issue of appropriate timely intervention points prior to or within the trading period will be discussed. In what periods and scenarios are adjustments to the cap worthwhile from an economic perspective? To what extent could minimum prices or price ranges make sense? What role could a strategic reserve play? By addressing these issues, it will be fundamentally discussed as to how the emissions trading scheme could be further developed and strengthened by greater flexibility. After a brief characterisation of emissions trading in theory and practice in Chapter 2, Chapter 3 will identify potential external shocks and unexpected developments which may impair the functioning of an emissions trading scheme. The current problems of cap setting for the third trading period of the EU ETS will be described in Chapter 4. Against this background, cap adjustments will be discussed in Chapter 5, minimum and maximum prices in Chapter 6 and strategic reserves in emissions trading in Chapter 7. The conclusions are summarised in Chapter 8.

Coordinating Decentralized Learning and Conflict Resolution across Agent Boundaries

Science.gov (United States)

Cheng, Shanjun

2012-01-01

It is crucial for embedded systems to adapt to the dynamics of open environments. This adaptation process becomes especially challenging in the context of multiagent systems because of scalability, partial information accessibility and complex interaction of agents. It is a challenge for agents to learn good policies, when they need to plan and…

The trade regime and the climate regime. Institutional evolution and adaptation

International Nuclear Information System (INIS)

Brewer, Thomas L.

2003-01-01

This article addresses concerns that the multilateral trade regime centered in the WTO and the emerging climate regime may conflict in ways that could be damaging to either or both. The article discusses the institutional and diplomatic context of these concerns, and it identifies the kinds of issues that are in question. The analysis suggests that there are opportunities for win-win outcomes in the interactions of the two regimes, for instance in the possibility of reducing fossil fuel subsidies. However, there are also problematic areas where they intersect. A core issue-and as yet an unresolved one-is whether and how emission credit trading and other activities envisioned by the Kyoto Protocol would be subject to WTO rules. The resolution of this issue will affect many other issues as well. Additional specific issues about the interactions of particular provisions in WTO agreements and the Kyoto Protocol are analyzed in a subsequent companion article in Climate Policy

Sensitivity Analysis of an Agent-Based Model of Culture's Consequences for Trade

NARCIS (Netherlands)

Burgers, S.L.G.E.; Jonker, C.M.; Hofstede, G.J.; Verwaart, D.

2010-01-01

This paper describes the analysis of an agent-based model’s sensitivity to changes in parameters that describe the agents’ cultural background, relational parameters, and parameters of the decision functions. As agent-based models may be very sensitive to small changes in parameter values, it is of

Anonymous electronic trading versus floor trading

OpenAIRE

Franke, Günter; Hess, Dieter

1995-01-01

This paper compares the attractiveness of floor trading and anonymous electronic trading systems. It is argued that in times of low information intensity the insight into the order book of the electronic trading system provides more valuable information than floor trading, but in times of high information intensity the reverse is true. Thus, the electronic system's market share in trading activity should decline in times of high information intensity. This hypothesis is tested by data on BUND...

ISHM-oriented adaptive fault diagnostics for avionics based on a distributed intelligent agent system

Science.gov (United States)

Xu, Jiuping; Zhong, Zhengqiang; Xu, Lei

2015-10-01

In this paper, an integrated system health management-oriented adaptive fault diagnostics and model for avionics is proposed. With avionics becoming increasingly complicated, precise and comprehensive avionics fault diagnostics has become an extremely complicated task. For the proposed fault diagnostic system, specific approaches, such as the artificial immune system, the intelligent agents system and the Dempster-Shafer evidence theory, are used to conduct deep fault avionics diagnostics. Through this proposed fault diagnostic system, efficient and accurate diagnostics can be achieved. A numerical example is conducted to apply the proposed hybrid diagnostics to a set of radar transmitters on an avionics system and to illustrate that the proposed system and model have the ability to achieve efficient and accurate fault diagnostics. By analyzing the diagnostic system's feasibility and pragmatics, the advantages of this system are demonstrated.

Evolutionary trade-offs in kidney injury and repair.

Science.gov (United States)

Lei, Yutian; Anders, Hans-Joachim

2017-11-01

Evolutionary medicine has proven helpful to understand the origin of human disease, e.g. in identifying causal roles of recent environmental changes impacting on human physiology (environment-phenotype mismatch). In contrast, diseases affecting only a limited number of members of a species often originate from evolutionary trade-offs for usually physiologic adaptations assuring reproductive success in the context of extrinsic threats. For example, the G1 and G2 variants of the APOL1 gene supporting control of Trypanosoma infection come with the trade-off that they promote the progression of kidney disease. In this review we extend the concept of evolutionary nephrology by discussing how the physiologic adaptations (danger responses) to tissue injury create evolutionary trade-offs that drive histopathological changes underlying acute and chronic kidney diseases. The evolution of multicellular organisms positively selected a number of danger response programs for their overwhelming benefits in assuring survival such as clotting, inflammation, epithelial healing and mesenchymal healing, i.e. fibrosis and sclerosis. Upon kidney injury these danger programs often present as pathomechanisms driving persistent nephron loss and renal failure. We explore how classic kidney disease entities involve insufficient or overshooting activation of these danger response programs for which the underlying genetic basis remains largely to be defined. Dissecting the causative and hierarchical relationships between danger programs should help to identify molecular targets to control kidney injury and to improve disease outcomes.

Manual for the energy trade. 3. new rev. and enl. ed.; Handbuch Energiehandel

Energy Technology Data Exchange (ETDEWEB)

Schwintowski, Hans-Peter (ed.) [Humboldt-Universitaet, Berlin (Germany)

2014-07-01

This manual sheds a light on the energy trade from both a legal and an empirical economic perspective. Its focus is on those business fields within the energy trade that are of foremost practical relevance, namely the OTC trade and the exchange trade. It also provides concise coverage of risk management systems in the energy trade along with a competent account of their implications with regard to supervisory regulations. In this, its third edition the manual addresses the latest developments in both the national and the international energy trade, including those seen in the gas storage market and its market access regulations; consideration is here also given to market transparency, market distortion and liquidity. The commentary on standard contracts (EFET) has been updated. The manual also addresses the adaptations made in the minimum requirements for risk management.

Observer-based distributed adaptive fault-tolerant containment control of multi-agent systems with general linear dynamics.

Science.gov (United States)

Ye, Dan; Chen, Mengmeng; Li, Kui

2017-11-01

In this paper, we consider the distributed containment control problem of multi-agent systems with actuator bias faults based on observer method. The objective is to drive the followers into the convex hull spanned by the dynamic leaders, where the input is unknown but bounded. By constructing an observer to estimate the states and bias faults, an effective distributed adaptive fault-tolerant controller is developed. Different from the traditional method, an auxiliary controller gain is designed to deal with the unknown inputs and bias faults together. Moreover, the coupling gain can be adjusted online through the adaptive mechanism without using the global information. Furthermore, the proposed control protocol can guarantee that all the signals of the closed-loop systems are bounded and all the followers converge to the convex hull with bounded residual errors formed by the dynamic leaders. Finally, a decoupled linearized longitudinal motion model of the F-18 aircraft is used to demonstrate the effectiveness. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

Survey of agent for intelligent information retrieval; Chiteki kensaku no tame no agent no chosa

Energy Technology Data Exchange (ETDEWEB)

Yazawa, T [Central Research Institute of Electric Power Industry, Tokyo (Japan)

1996-09-01

Development of agent systems has been surveyed, to classify and arrange characteristic functions of the agents, and to grasp the realization situation of these agents in their development. In addition, prospective functions of information retrieval systems using the agents at maximum and functions to be developed among these in the future are clarified. The agents are characterized by the expression function, communication function, planning function, adaptive function, and learning function. The agents are desired to be classified into interface agents whose works are to respond to individual workers, coordinator agents which conduct works with high pervasion, such as assignment of works and their control, and task agents which conduct specialized works for individual examples. Thus, design and configuration of the agent system, and improvement and expansion of system functions can be effectively and easily conducted. 52 refs., 5 figs., 3 tabs.

The Emergence of Groups and Inequality through Co-Adaptation.

Directory of Open Access Journals (Sweden)

Jon Atwell

Full Text Available The emergence of groups and of inequality is often traced to pre-existing differences, exclusionary practices, or resource accumulation processes, but can the emergence of groups and their differential success simply be a feature of the behaviors of a priori equally-capable actors who have mutually adapted? Using a simple model of behavioral co-adaptation among agents whose individual actions construct a common environment, we present evidence that the formation of unequal groups is endemic to co-adaptive processes that endogenously alter the environment; agents tend to separate into two groups, one whose members stop adapting earliest (the in-group, and another comprising agents who continue to adapt (the out-group. Over a wide range of model parameters, members of the in-group are rewarded more on average than members of the out-group. The primary reason is that the in-group is able to have a more profound influence on the environment and mold it to the benefit of its members. This molding capacity proves more beneficial than the persistence of adaptivity, yet, crucially, which agents are able to form a coalition to successfully exert this control is strongly contingent on random aspects of the set of agent behaviors. In this paper, we present the model, relevant definitions, and results. We then discuss its implications for the study of complex adaptive systems generally.

Trade and production fragmentation : Central European economies in European Union networks of production and marketing

OpenAIRE

Kaminski, Bartlomiej; Ng, Francis

2001-01-01

Developments driven by trade liberalization and tehcnological progress mean that old development strategies, based on state intervention and trade protection, no longer work. Global competition has brought a growing emphasis on product standards, rapid innovation, adaptability, and speedy response. Technology has made possible the fragmentation of production. Firms that become part of glob...

Livestock Disease Management for Trading Across Different Regulatory Regimes.

Science.gov (United States)

Bate, Andrew M; Jones, Glyn; Kleczkowski, Adam; Naylor, Rebecca; Timmis, Jon; White, Piran C L; Touza, Julia

2018-02-12

The maintenance of livestock health depends on the combined actions of many different actors, both within and across different regulatory frameworks. Prior work recognised that private risk management choices have the ability to reduce the spread of infection to trading partners. We evaluate the efficiency of farmers' alternative biosecurity choices in terms of their own-benefits from unilateral strategies and quantify the impact they may have in filtering the disease externality of trade. We use bovine viral diarrhoea (BVD) in England and Scotland as a case study, since this provides an example of a situation where contrasting strategies for BVD management occur between selling and purchasing farms. We use an agent-based bioeconomic model to assess the payoff dependence of farmers connected by trade but using different BVD management strategies. We compare three disease management actions: test-cull, test-cull with vaccination and vaccination alone. For a two-farm trading situation, all actions carried out by the selling farm provide substantial benefits to the purchasing farm in terms of disease avoided, with the greatest benefit resulting from test-culling with vaccination on the selling farm. Likewise, unilateral disease strategies by purchasers can be effective in reducing disease risks created through trade. We conclude that regulation needs to balance the trade-off between private gains from those bearing the disease management costs and the positive spillover effects on others.

Trade in the telecoupling framework: evidence from the metals industry

Directory of Open Access Journals (Sweden)

Hang Xiong

2018-03-01

Full Text Available As a conceptual framework for understanding contemporary sustainability challenges, telecoupling emphasizes the importance of socioeconomic and environmental interactions over long distances. These long-distance interactions can occur through multiple human activities. We focus on international trade, a major channel of telecoupling flows, and in particular on the international trade of metals. We use the data of physical products and embedded greenhouse gas (GHG emissions trade in the World Input-Output Database (WIOD to quantitatively examine how countries contribute to both economic and environmental flows through the trade of metals, but also how that contribution varies depending on their position in the global value chain (GVC of contemporary international trade. This analysis is built on previously developed techniques for decomposing gross exports of products, which we apply to examine embedded GHG emissions. We make comparisons between countries' contributions to flows of economic value versus embedded GHG emissions, but also examine contributions beyond total volumes of trade and bilateral trade. Specifically, we quantify the economic and environmental spillover effects that occur in contemporary international trade because of the GVC in which flows of intermediate goods form components in other subsequently traded goods. We interpret differences between countries' contributions to the flows of economic value versus embedded GHG emissions as being related to the intensity and efficiency of resource use during production. In turn, differences in contributions to direct trade flows versus spillover flows are related to their positions in the GVC. Subsequently, we discuss other elements of the telecoupling framework in trade, i.e., agents, causes, and effects. Quantitatively incorporating these telecoupling framework elements alongside spillover flows will enable investigation of dynamics and relationships that traditional trade theories

An Approach for Autonomy: A Collaborative Communication Framework for Multi-Agent Systems

Science.gov (United States)

Dufrene, Warren Russell, Jr.

2005-01-01

Research done during the last three years has studied the emersion properties of Complex Adaptive Systems (CAS). The deployment of Artificial Intelligence (AI) techniques applied to remote Unmanned Aerial Vehicles has led the author to investigate applications of CAS within the field of Autonomous Multi-Agent Systems. The core objective of current research efforts is focused on the simplicity of Intelligent Agents (IA) and the modeling of these agents within complex systems. This research effort looks at the communication, interaction, and adaptability of multi-agents as applied to complex systems control. The embodiment concept applied to robotics has application possibilities within multi-agent frameworks. A new framework for agent awareness within a virtual 3D world concept is possible where the vehicle is composed of collaborative agents. This approach has many possibilities for applications to complex systems. This paper describes the development of an approach to apply this virtual framework to the NASA Goddard Space Flight Center (GSFC) tetrahedron structure developed under the Autonomous Nano Technology Swarm (ANTS) program and the Super Miniaturized Addressable Reconfigurable Technology (SMART) architecture program. These projects represent an innovative set of novel concepts deploying adaptable, self-organizing structures composed of many tetrahedrons. This technology is pushing current applied Agents Concepts to new levels of requirements and adaptability.

Design of a Two-level Adaptive Multi-Agent System for Malaria Vectors driven by an ontology

Directory of Open Access Journals (Sweden)

Etang Josiane

2007-07-01

Full Text Available Abstract Background The understanding of heterogeneities in disease transmission dynamics as far as malaria vectors are concerned is a big challenge. Many studies while tackling this problem don't find exact models to explain the malaria vectors propagation. Methods To solve the problem we define an Adaptive Multi-Agent System (AMAS which has the property to be elastic and is a two-level system as well. This AMAS is a dynamic system where the two levels are linked by an Ontology which allows it to function as a reduced system and as an extended system. In a primary level, the AMAS comprises organization agents and in a secondary level, it is constituted of analysis agents. Its entry point, a User Interface Agent, can reproduce itself because it is given a minimum of background knowledge and it learns appropriate "behavior" from the user in the presence of ambiguous queries and from other agents of the AMAS in other situations. Results Some of the outputs of our system present a series of tables, diagrams showing some factors like Entomological parameters of malaria transmission, Percentages of malaria transmission per malaria vectors, Entomological inoculation rate. Many others parameters can be produced by the system depending on the inputted data. Conclusion Our approach is an intelligent one which differs from statistical approaches that are sometimes used in the field. This intelligent approach aligns itself with the distributed artificial intelligence. In terms of fight against malaria disease our system offers opportunities of reducing efforts of human resources who are not obliged to cover the entire territory while conducting surveys. Secondly the AMAS can determine the presence or the absence of malaria vectors even when specific data have not been collected in the geographical area. In the difference of a statistical technique, in our case the projection of the results in the field can sometimes appeared to be more general.

Portfolio of automated trading systems: complexity and learning set size issues.

Science.gov (United States)

Raudys, Sarunas

2013-03-01

In this paper, we consider using profit/loss histories of multiple automated trading systems (ATSs) as N input variables in portfolio management. By means of multivariate statistical analysis and simulation studies, we analyze the influences of sample size (L) and input dimensionality on the accuracy of determining the portfolio weights. We find that degradation in portfolio performance due to inexact estimation of N means and N(N - 1)/2 correlations is proportional to N/L; however, estimation of N variances does not worsen the result. To reduce unhelpful sample size/dimensionality effects, we perform a clustering of N time series and split them into a small number of blocks. Each block is composed of mutually correlated ATSs. It generates an expert trading agent based on a nontrainable 1/N portfolio rule. To increase the diversity of the expert agents, we use training sets of different lengths for clustering. In the output of the portfolio management system, the regularized mean-variance framework-based fusion agent is developed in each walk-forward step of an out-of-sample portfolio validation experiment. Experiments with the real financial data (2003-2012) confirm the effectiveness of the suggested approach.

Adaptive Sniping for Volatile and Stable Continuous Double Auction Markets

Science.gov (United States)

Toft, I. E.; Bagnall, A. J.

This paper introduces a new adaptive sniping agent for the Continuous Double Auction. We begin by analysing the performance of the well known Kaplan sniper in two extremes of market conditions. We generate volatile and stable market conditions using the well known Zero Intelligence-Constrained agent and a new zero-intelligence agent Small Increment (SI). ZI-C agents submit random but profitable bids/offers and cause high volatility in prices and individual trader performance. Our new zero-intelligence agent, SI, makes small random adjustments to the outstanding bid/offer and hence is more cautious than ZI-C. We present results for SI in self-play and then analyse Kaplan in volatile and stable markets. We demonstrate that the non-adaptive Kaplan sniper can be configured to suit either market conditions, but no single configuration is performs well across both market types. We believe that in a dynamic auction environment where current or future market conditions cannot be predicted a viable sniping strategy should adapt its behaviour to suit prevailing market conditions. To this end, we propose the Adaptive Sniper (AS) agent for the CDA. AS traders classify sniping opportunities using a statistical model of market activity and adjust their classification thresholds using a Widrow-Hoff adapted search. Our AS agent requires little configuration, and outperforms the original Kaplan sniper in volatile and stable markets, and in a mixed trader type scenario that includes adaptive strategies from the literature.

Strategic farsighted learning in competitive multi-agent games

NARCIS (Netherlands)

t Hoen, P.J.; Bohté, S.M.; Poutré, la J.A.; Brewka, G.; Coradeschi, S.; Perini, A.

2006-01-01

We describe a generalized Q-learning type algorithm for reinforcement learning in competitive multi-agent games. We make the observation that in a competitive setting with adaptive agents an agent's actions will (likely) result in changes in the opponents policies. In addition to accounting for the

Network Management using Multi-Agents System

Directory of Open Access Journals (Sweden)

Nestor DUQUE

2013-07-01

Full Text Available This paper aims to present a multiagent system for network management. The models developed for the proposed system defines certain intelligent agents interact to achieve the objectives and requirements of the multiagent organization.These agents have the property of being adaptive, acquire knowledge and skills to make decisions according to the actual state of the network that is represented in the information base, MIB, SNMP devices. The ideal state of the network policy is defined by the end user entered, which contain the value that should have performance variables and other parameters such as the frequency with which these variables should be monitored.. An agent based architecture increase the integration, adaptability, cooperation, autonomy and the efficient operation in heterogeneous environment in the network supervision. 

Network Management using Multi-Agents System

Directory of Open Access Journals (Sweden)

Gustavo ISAZA

2012-12-01

Full Text Available This paper aims to present a multiagent system for network management. The models developed for the proposed system defines certain intelligent agents interact to achieve the objectives and requirements of the multiagent organization.These agents have the property of being adaptive, acquire knowledge and skills to make decisions according to the actual state of the network that is represented in the information base, MIB, SNMP devices. The ideal state of the network policy is defined by the end user entered, which contain the value that should have performance variables and other parameters such as the frequency with which these variables should be monitored.. An agent based architecture increase the integration, adaptability, cooperation, autonomy and the efficient operation in heterogeneous environment in the network supervision. 

Análise empírica da prática de insider trading em processos de fusões e aquisições recentes na economia brasileira Empirical analysis of insider trading in recent brazilian mergers and acquisitions

Directory of Open Access Journals (Sweden)

Marcos Antônio de Camargos

2008-12-01

Full Text Available As negociações com uso de informações privilegiadas (insider trading criam oportunidades para que alguns agentes do mercado lucrem em detrimento de outros, levando a uma transferência de riqueza entre os acionistas. O anúncio de uma fusão ou aquisição é um momento oportuno para essa prática, visto que quase sempre causa impactos significativos nas expectativas dos agentes do mercado e nos preços dos títulos. Este artigo analisou se essa prática esteve presente em processos de fusões e aquisições recentes, realizados por grandes empresas brasileiras, utilizando-se de um estudo de evento para o qual, além da análise do retorno acionário anormal, fez-se a comparação de médias de variáveis sinalizadoras do comportamento dos títulos no mercado (liquidez. Para a análise foram utilizadas ações preferenciais, ordinárias e os American Depositary Receipts (ADRs de dez empresas diferentes. Foi encontrada evidência empírica da prática de insider trading no retorno acionário anormal e na quantidade de negociações, além de se observarem indícios dessa prática nas demais variáveis analisadas, o que sinaliza que ocorreu um aumento da liquidez dos títulos analisados antes do anúncio.Insider trading creates opportunities for some agents in the market to profit in detriment of others thereby transferring wealth between shareholders. Announcement of a merger or acquisition is an opportunity for this practice as it usually causes significant price changes and impacts stock market expectations of these agents. An analysis was made to detect insider trading in recent mergers and acquisitions by large Brazilian companies, An Event Study searched for abnormal returns and compared averages of variables signaling behavior in the market (liquidity for common and preferred stocks as well as American Depositary Receipts of ten companies. Empirical analysis identified insider trading by abnormal returns and volumes of trading with

Trading scheme 'key' to low-carbon economy

International Nuclear Information System (INIS)

2006-01-01

Federal Opposition Leader Kim Beazley has emphasised the importance of getting the economics of environmental policy right by introducing market-based mechanisms for pricing emissions. 'Market-based mechanisms such as emissions trading are central to moving to a low-carbon economy,' he said in his latest blueprint. 'A functioning carbon market will deliver a price signal, so there is a long-term incentive to cut emissions further, and a mechanism for trading, so that energy can be allocated efficiently in the economy. It will also encourage greater private investment in clean energy technology.' Mr Beazley said the new market would also reward the many companies who were already adapting to a carbon-constrained world. 'This includes those global companies in Australia that already operate in emissions trading markets overseas. An effective price signal for carbon in Australia will allow these companies to benefit directly from their good corporate citizenship and long-term vision.' Mr Beazley has committed a federal Labor government to work with state governments and business to establish the national trading scheme. He also criticised the Federal Government for refusing to ratify the Kyoto Protocol, which he argued excluded Australian businesses from participating in the emerging global carbon trade. This made it harder for businesses to break into the market for cleaner production technologies overseas. While again admitting Kyoto was not perfect, Mr Beazley said ratification would see Australia part of what would potentially be 'the biggest market in the world by 2020'. He said the recent Asia Pacific Climate Change Pact was a positive step but was not an alternative to Kyoto. 'Above all, it has no economic mechanisms to drive further change. 'Without ratifying Kyoto some of our businesses are missing out on effective participation in international schemes that offer substantial financial rewards for greenhouse gas reductions. 'By ratifying Kyoto and adopting

Adaptive delta management : Roots and branches

NARCIS (Netherlands)

Timmermans, J.S.; Haasnoot, M.; Hermans, L.M.; Kwakkel, J.H.; Rutten, M.M.; Thissen, W.A.H.

2015-01-01

Deltas are generally recognized as vulnerable to climate change and therefore a salient topic in adaptation science. Deltas are also highly dynamic systems viewed from physical (erosion, sedimentation, subsidence), social (demographic), economic (trade), infrastructures (transport, energy,

Adaptive Delta Management : Roots and Branches

NARCIS (Netherlands)

Timmermans, Jos; Haasnoot, Marjolijn; Hermans, Leon; Kwakkel, Jan H.; Rutten, Maarten; Thissen, Wil A.H.; Mynett, Arthur

2015-01-01

Deltas are generally recognized as vulnerable to climate change and therefore a salient topic in adaptation science. Deltas are also highly dynamic systems viewed from physical (erosion, sedimentation, subsidence), social (demographic), economic (trade), infrastructures (transport, energy,

Evaluation of Market Design Agents: The Mertacor Perspective

Science.gov (United States)

Stavrogiannis, Lampros C.; Mitkas, Pericles A.

The annual Trading Agent Competition for Market Design, CAT, provides a testbed to study the mechanisms that modern stock exchanges use in their effort to attract potential traders while maximizing their profit. This paper presents an evaluation of the agents that participated in the 2008 competition. The evaluation is based on the analysis of the CAT finals as well as on the results obtained from post-tournament experiments. We present Mertacor, our entrant for 2008, and compare it with the other available agents. In addition, we introduce a simple yet effective way of computing the global competitive equilibrium that Mertacor utilizes and discuss its importance for the game.

Multi-agent agro-economic simulation of irrigation water demand with climate services for climate change adaptation

Directory of Open Access Journals (Sweden)

Stefano Balbi

2013-09-01

Full Text Available Farmers’ irrigation practices play a crucial role in the sustainability of crop production and water consumption, and in the way they deal with the current and future effects of climate change. In this study, a system dynamic multi-agent model adopting the soil water balance provided by the Food and Agriculture Organization (FAO Irrigation and Drainage Paper 56 was developed to explore how farmers’ decision making may affect future water needs and use with a focus on the role of climate services, i.e. forecasts and insurance. A climatic projection record representing the down-scaled A1B market scenario (a balance across all sources of the assessment report of the Intergovernmental Panel on Climate Change (IPCC is used to produce future daily data about relative humidity, precipitation, temperature and wind speed. Two types of meteorological services are made available: i a bi-weekly bulletin; and ii seasonal forecasts. The precision of these services was altered to represent different conditions, from perfect knowledge to poor forecasts. Using the available forecasts, farming agents take adaptation decisions concerning crop allocation and irrigation management on the basis of their own risk attitudes. Farmers’ attitudes are characterized by fuzzy classifications depending on age, relative income and crop profitability. Farming agents’ adaptation decisions directly affect the crop and irrigation parameters, which in turn affect future water needs on a territorial level. By incorporating available and future meteorological services, the model allows the farmer’s decision making-process to be explored together with the consequent future irrigation water demand for the period 2015 to 2030. The model prototype is applied to a data set of the Venice Lagoon Watershed, an area of 2038 km2 in north-east Italy, for a preliminary test of its performance and to design future development objectives.

Trading volume and the number of trades

OpenAIRE

Marwan Izzeldin

2007-01-01

Trading volume and the number of trades are both used as proxies for market activity, with disagreement as to which is the better proxy for market activity. This paper investigates this issue using high frequency data for Cisco and Intel in 1997. A number of econometric methods are used, including GARCH augmented with lagged trading volume and number of trades, tests based on moment restrictions, regression analysis of volatility on volume and trades, normality of returns when standardized by...

Regional Trade Agreement and Agricultural Trade in East African ...

African Journals Online (AJOL)

Intra-EAC trade is very low, that is, at 9 per cent of the total regional trade, but it is on upward trend. Agricultural trade accounts for over 40 per cent of the intra-EAC trade. This study investigated the effect of EAC regional trade agreement on the regions agricultural trade by analyzing the degree of trade creation and ...

Trade creation and trade diversion in the Canada - United States Free Trade Agreement

OpenAIRE

Kimberly A. Clausing

2001-01-01

In this paper the changes in trade patterns introduced by the Canada-United States Free Trade Agreement are examined. Variation in the extent of tariff liberalization under the agreement is used to identify the impact of tariff liberalization on the growth of trade both with member countries and non-member countries. Data at the commodity level are used, and the results indicate that the Canada-United States Free Trade Agreement had substantial trade creation effects, with little evidence of ...

A Goal Oriented Approach for Modeling and Analyzing Security Trade-Offs

Science.gov (United States)

Elahi, Golnaz; Yu, Eric

In designing software systems, security is typically only one design objective among many. It may compete with other objectives such as functionality, usability, and performance. Too often, security mechanisms such as firewalls, access control, or encryption are adopted without explicit recognition of competing design objectives and their origins in stakeholder interests. Recently, there is increasing acknowledgement that security is ultimately about trade-offs. One can only aim for "good enough" security, given the competing demands from many parties. In this paper, we examine how conceptual modeling can provide explicit and systematic support for analyzing security trade-offs. After considering the desirable criteria for conceptual modeling methods, we examine several existing approaches for dealing with security trade-offs. From analyzing the limitations of existing methods, we propose an extension to the i* framework for security trade-off analysis, taking advantage of its multi-agent and goal orientation. The method was applied to several case studies used to exemplify existing approaches.

Trade Policy

OpenAIRE

Murray Gibbs

2007-01-01

In an otherwise insightful and thoughtful article, Sebastian Pfotenhauer (Trade Policy Is Science Policy,” Issues, Fall 2013) might better have entitled his contribution “Trade Policy Needs to Be Reconciled with Science Policy.” The North American Free Trade Agreement (NAFTA) and the agreements administered by the World Trade Organization, particularly the General Agreement on Tariffs and Trade (GATT) and the Technical Barriers to Trade (TBT), were adopted to promote international trade and i...

Fortune Favours the Bold: An Agent-Based Model Reveals Adaptive Advantages of Overconfidence in War

Science.gov (United States)

Johnson, Dominic D. P.; Weidmann, Nils B.; Cederman, Lars-Erik

2011-01-01

Overconfidence has long been considered a cause of war. Like other decision-making biases, overconfidence seems detrimental because it increases the frequency and costs of fighting. However, evolutionary biologists have proposed that overconfidence may also confer adaptive advantages: increasing ambition, resolve, persistence, bluffing opponents, and winning net payoffs from risky opportunities despite occasional failures. We report the results of an agent-based model of inter-state conflict, which allows us to evaluate the performance of different strategies in competition with each other. Counter-intuitively, we find that overconfident states predominate in the population at the expense of unbiased or underconfident states. Overconfident states win because: (1) they are more likely to accumulate resources from frequent attempts at conquest; (2) they are more likely to gang up on weak states, forcing victims to split their defences; and (3) when the decision threshold for attacking requires an overwhelming asymmetry of power, unbiased and underconfident states shirk many conflicts they are actually likely to win. These “adaptive advantages” of overconfidence may, via selection effects, learning, or evolved psychology, have spread and become entrenched among modern states, organizations and decision-makers. This would help to explain the frequent association of overconfidence and war, even if it no longer brings benefits today. PMID:21731627

Cross-border electricity market effects due to price caps in an emission trading system: An agent-based approach

International Nuclear Information System (INIS)

Richstein, Jörn C.; Chappin, Emile J.L.; Vries, Laurens J. de

2014-01-01

The recent low CO 2 prices in the European Union Emission Trading Scheme (EU ETS) have triggered a discussion whether the EU ETS needs to be adjusted. We study the effects of CO 2 price floors and a price ceiling on the dynamic investment pathway of two interlinked electricity markets (loosely based on Great Britain, which already has introduced a price floor, and on Central Western Europe). Using an agent-based electricity market simulation with endogenous investment and a CO 2 market (including banking), we analyse the cross-border effects of national policies as well as system-wide policy options. A common, moderate CO 2 auction reserve price results in a more continuous decarbonisation pathway. This reduces CO 2 price volatility and the occurrence of carbon shortage price periods, as well as the average cost to consumers. A price ceiling can shield consumers from extreme price shocks. These price restrictions do not cause a large risk of an overall emissions overshoot in the long run. A national price floor lowers the cost to consumers in the other zone; the larger the zone with the price floor, the stronger the effect. Price floors that are too high lead to inefficiencies in investment choices and to higher consumer costs. - Highlights: • Cross-border effects of CO 2 policies were investigated with an agent-based model. • The current EU ETS might cause CO 2 price shocks and CO 2 price volatility. • A CO 2 auction reserve price does not lower welfare, but lowers CO 2 price volatility. • A national CO 2 price floor lowers consumer cost in the other countries. • A CO 2 price ceiling does not lead to an overshoot of emissions

Between Complexity and Parsimony: Can Agent-Based Modelling Resolve the Trade-off

DEFF Research Database (Denmark)

Nielsen, Helle Ørsted; Malawska, Anna Katarzyna

2013-01-01

to BR- based policy studies would be to couple research on bounded ra-tionality with agent-based modeling. Agent-based models (ABMs) are computational models for simulating the behavior and interactions of any number of decision makers in a dynamic system. Agent-based models are better suited than...... are general equilibrium models for capturing behavior patterns of complex systems. ABMs may have the potential to represent complex systems without oversimplifying them. At the same time, research in bounded rationality and behavioral economics has already yielded many insights that could inform the modeling......While Herbert Simon espoused development of general models of behavior, he also strongly advo-cated that these models be based on realistic assumptions about humans and therefore reflect the complexity of human cognition and social systems (Simon 1997). Hence, the model of bounded rationality...

Learning to trade via direct reinforcement.

Science.gov (United States)

Moody, J; Saffell, M

2001-01-01

We present methods for optimizing portfolios, asset allocations, and trading systems based on direct reinforcement (DR). In this approach, investment decision-making is viewed as a stochastic control problem, and strategies are discovered directly. We present an adaptive algorithm called recurrent reinforcement learning (RRL) for discovering investment policies. The need to build forecasting models is eliminated, and better trading performance is obtained. The direct reinforcement approach differs from dynamic programming and reinforcement algorithms such as TD-learning and Q-learning, which attempt to estimate a value function for the control problem. We find that the RRL direct reinforcement framework enables a simpler problem representation, avoids Bellman's curse of dimensionality and offers compelling advantages in efficiency. We demonstrate how direct reinforcement can be used to optimize risk-adjusted investment returns (including the differential Sharpe ratio), while accounting for the effects of transaction costs. In extensive simulation work using real financial data, we find that our approach based on RRL produces better trading strategies than systems utilizing Q-learning (a value function method). Real-world applications include an intra-daily currency trader and a monthly asset allocation system for the S&P 500 Stock Index and T-Bills.

International provision of trade services, trade, and fragmentation

OpenAIRE

Deardorff, Alan V.

2001-01-01

The author examines the special role that trade liberalization in services industries can play in stimulating trade in both services, and goods. International trade in goods requires inputs from such trade services as transportation, insurance, and finance, for example. Restrictions on services across borders, and within foreign countries add costs, and barriers to international trade. Lib...

ADAM: ADaptive Autonomous Machine

NARCIS (Netherlands)

van Oosten, Daan C.; Nijenhuis, Lucas F.J.; Bakkers, André; Vervoort, Wiek

1996-01-01

This paper describes a part of the development of an adaptive autonomous machine that is able to move in an unknown world extract knowledge out of the perceived data, has the possibility to reason, and finally has the capability to exchange experiences and knowledge with other agents. The agent is

27 CFR 28.226 - Removals of beer by agent on behalf of brewer.

Science.gov (United States)

2010-04-01

... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Removals of beer by agent... TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS EXPORTATION OF ALCOHOL Exportation of Beer With Benefit of Drawback Execution of Claims § 28.226 Removals of beer by agent on behalf of brewer...

Dimensions of Usability: Cougaar, Aglets and Adaptive Agent Architecture (AAA)

Energy Technology Data Exchange (ETDEWEB)

Haack, Jereme N.; Cowell, Andrew J.; Gorton, Ian

2004-06-20

Research and development organizations are constantly evaluating new technologies in order to implement the next generation of advanced applications. At Pacific Northwest National Laboratory, agent technologies are perceived as an approach that can provide a competitive advantage in the construction of highly sophisticated software systems in a range of application areas. An important factor in selecting a successful agent architecture is the level of support it provides the developer in respect to developer support, examples of use, integration into current workflow and community support. Without such assistance, the developer must invest more effort into learning instead of applying the technology. Like many other applied research organizations, our staff are not dedicated to a single project and must acquire new skills as required, underlining the importance of being able to quickly become proficient. A project was instigated to evaluate three candidate agent toolkits across the dimensions of support they provide. This paper reports on the outcomes of this evaluation and provides insights into the agent technologies evaluated.

Enhancing agent safety through autonomous environment adaptation

CSIR Research Space (South Africa)

Rosman, Benjamin S

2015-08-01

Full Text Available limit their ability to interact with and explore their environments. In this work we address this risk through the incorporation of a caregiver robot, and present a model allowing it to autonomously adapt its environment to minimize danger for other...

Trade and Industrial Policy Strategies (TIPS) Core Grant - Phase IV ...

International Development Research Centre (IDRC) Digital Library (Canada)

Established in 1996, Trade and Industrial Policy Strategies (TIPS) is an organization that coordinates a network of researchers that seeks to provide the Government of ... International Water Resources Association, in close collaboration with IDRC, is holding a webinar titled “Climate change and adaptive water management: ...

Aspects of agents for safeguards

International Nuclear Information System (INIS)

Kotte, U.

1999-01-01

With the development of the Internet and the WWW, information treatment has gained a new dimension. (Intelligent) software agents are one of the means expected to relieve human staff of the burden of information overload, and in the future to contribute to safeguards data acquisition, data evaluation and decision-making. An overview is given for the categories of Internet, intranet and desktop agents. Aspects of the potential application of agents are described in three fields: information access and delivery, collaboration and workflow management, adaptive interfaces and learning assistants. Routine application of agents is not yet in sight, but the scientific and technical progress seems to be encouraging. (author)

Adaptive Source Localization Based Station Keeping of Autonomous Vehicles

KAUST Repository

Guler, Samet; Fidan, Baris; Dasgupta, Soura; Anderson, Brian D.O.; Shames, Iman

2016-01-01

We study the problem of driving a mobile sensory agent to a target whose location is specied only in terms of the distances to a set of sensor stations or beacons. The beacon positions are unknown, but the agent can continuously measure its distances to them as well as its own position. This problem has two particular applications: (1) capturing a target signal source whose distances to the beacons are measured by these beacons and broadcasted to a surveillance agent, (2) merging a single agent to an autonomous multi-agent system so that the new agent is positioned at desired distances from the existing agents. The problem is solved using an adaptive control framework integrating a parameter estimator producing beacon location estimates, and an adaptive motion control law fed by these estimates to steer the agent toward the target. For location estimation, a least-squares adaptive law is used. The motion control law aims to minimize a convex cost function with unique minimizer at the target location, and is further augmented for persistence of excitation. Stability and convergence analysis is provided, as well as simulation results demonstrating performance and transient behavior.

Adaptive Source Localization Based Station Keeping of Autonomous Vehicles

KAUST Repository

Guler, Samet

2016-10-26

We study the problem of driving a mobile sensory agent to a target whose location is specied only in terms of the distances to a set of sensor stations or beacons. The beacon positions are unknown, but the agent can continuously measure its distances to them as well as its own position. This problem has two particular applications: (1) capturing a target signal source whose distances to the beacons are measured by these beacons and broadcasted to a surveillance agent, (2) merging a single agent to an autonomous multi-agent system so that the new agent is positioned at desired distances from the existing agents. The problem is solved using an adaptive control framework integrating a parameter estimator producing beacon location estimates, and an adaptive motion control law fed by these estimates to steer the agent toward the target. For location estimation, a least-squares adaptive law is used. The motion control law aims to minimize a convex cost function with unique minimizer at the target location, and is further augmented for persistence of excitation. Stability and convergence analysis is provided, as well as simulation results demonstrating performance and transient behavior.

Adaptive representations for reinforcement learning

NARCIS (Netherlands)

Whiteson, S.

2010-01-01

This book presents new algorithms for reinforcement learning, a form of machine learning in which an autonomous agent seeks a control policy for a sequential decision task. Since current methods typically rely on manually designed solution representations, agents that automatically adapt their own

Reinforcement Learning for Constrained Energy Trading Games With Incomplete Information.

Science.gov (United States)

Wang, Huiwei; Huang, Tingwen; Liao, Xiaofeng; Abu-Rub, Haitham; Chen, Guo

2017-10-01

This paper considers the problem of designing adaptive learning algorithms to seek the Nash equilibrium (NE) of the constrained energy trading game among individually strategic players with incomplete information. In this game, each player uses the learning automaton scheme to generate the action probability distribution based on his/her private information for maximizing his own averaged utility. It is shown that if one of admissible mixed-strategies converges to the NE with probability one, then the averaged utility and trading quantity almost surely converge to their expected ones, respectively. For the given discontinuous pricing function, the utility function has already been proved to be upper semicontinuous and payoff secure which guarantee the existence of the mixed-strategy NE. By the strict diagonal concavity of the regularized Lagrange function, the uniqueness of NE is also guaranteed. Finally, an adaptive learning algorithm is provided to generate the strategy probability distribution for seeking the mixed-strategy NE.

THE WORLD TRADE ORGANIZATION (WTO FREE TRADE WITHIN FAIR TRADE CHALLENGES

Directory of Open Access Journals (Sweden)

M. Ya’kub Aiyub Kadir

2014-06-01

Full Text Available Free trade and fair trade are considered an ambiguous term with relative meanings of identification. Objectively, free and fair trade does not mean completely free and fair, but it means trade under binding rules obeyed by member countries as a consequence of their commitment after signing and ratification of the WTO agreements. Hence, this paper aims at exploring the issue and does an effort to harmonise between free trade and fair trade within the WTO system. Perdagangan bebas dan perdagangan yang adil adalah dua istilah yang ambigu maknanya. Secara obyektif, perdagangan bebas tidak bermakna bebas dan adil seluruhnya, tetapi bermakna sebuah perdagangan di bawah aturan-aturan mengikat setelah negara anggota menandatangani dan meratifikasi kesepakatan WTO. Tetapi dalam realitas kebanyakan Negara, terutama negara berkembang tidak mampu untuk membuka pasar dan menurunkan tarif secara keseluruhan. Persoalan tidak berimbangnya kekuatan, kurang demokrasi, krisis legitimasi dan dobel standar dalam WTO sistem merupakan sebuah tantangan yang masih berlanjut. Paper ini akan mengkaji persoalan ini dan berupaya mengharmonisasikan antara perdagangan bebas dan adil dalam sistem WTO.

THE WORLD TRADE ORGANIZATION (WTO FREE TRADE WITHIN FAIR TRADE CHALLENGES

Directory of Open Access Journals (Sweden)

M. Ya’kub Aiyub Kadir

2014-06-01

Full Text Available Free trade and fair trade are considered an ambiguous term with relative meanings of identification. Objectively, free and fair trade does not mean completely free and fair, but it means trade under binding rules obeyed by member countries as a consequence of their commitment after signing and ratification of the WTO agreements. Hence, this paper aims at exploring the issue and does an effort to harmonise between free trade and fair trade within the WTO system.   Perdagangan bebas dan perdagangan yang adil adalah dua istilah yang ambigu maknanya. Secara obyektif, perdagangan bebas tidak bermakna bebas dan adil seluruhnya, tetapi bermakna sebuah perdagangan di bawah aturan-aturan mengikat setelah negara anggota menandatangani dan meratifikasi kesepakatan WTO. Tetapi dalam realitas kebanyakan Negara, terutama negara berkembang tidak mampu untuk membuka pasar dan menurunkan tarif secara keseluruhan. Persoalan tidak berimbangnya kekuatan, kurang demokrasi, krisis legitimasi dan dobel standar dalam WTO sistem merupakan sebuah tantangan yang masih berlanjut. Paper ini akan mengkaji persoalan ini dan berupaya mengharmonisasikan antara perdagangan bebas dan adil dalam sistem WTO.

An Agent Model Integrating an Adaptive Model for Environmental Dynamics

NARCIS (Netherlands)

Treur, J.; Umair, M.

2011-01-01

The environments in which agents are used often may be described by dynamical models, e.g., in the form of a set of differential equations. In this paper, an agent model is proposed that can perform model-based reasoning about the environment, based on a numerical (dynamical system) model of the

Assessment of the safety of aquatic animal commodities for international trade: the OIE Aquatic Animal Health code.

Science.gov (United States)

Oidtmann, B; Johnston, C; Klotins, K; Mylrea, G; Van, P T; Cabot, S; Martin, P Rosado; Ababouch, L; Berthe, F

2013-02-01

Trading of aquatic animals and aquatic animal products has become increasingly globalized during the last couple of decades. This commodity trade has increased the risk for the spread of aquatic animal pathogens. The World Organisation for Animal Health (OIE) is recognized as the international standard-setting organization for measures relating to international trade in animals and animal products. In this role, OIE has developed the Aquatic Animal Health Code, which provides health measures to be used by competent authorities of importing and exporting countries to avoid the transfer of agents pathogenic for animals or humans, whilst avoiding unjustified sanitary barriers. An OIE ad hoc group developed criteria for assessing the safety of aquatic animals or aquatic animal products for any purpose from a country, zone or compartment not declared free from a given disease 'X'. The criteria were based on the absence of the pathogenic agent in the traded commodity or inactivation of the pathogenic agent by the commercial processing used to produce the commodity. The group also developed criteria to assess the safety of aquatic animals or aquatic animal products for retail trade for human consumption from potentially infected areas. Such commodities were assessed considering the form and presentation of the product, the expected volume of waste tissues generated by the consumer and the likely presence of viable pathogenic agent in the waste. The ad hoc group applied the criteria to commodities listed in the individual disease chapters of the Aquatic Animal Health Code (2008 edition). Revised lists of commodities for which no additional measures should be required by the importing countries regardless of the status for disease X of the exporting country were developed and adopted by the OIE World Assembly of Delegates in May 2011. The rationale of the criteria and their application will be explained and demonstrated using examples. © 2012 Crown Copyright. Reproduced

The fitness costs and trade-off shapes associated with the exclusion of nine antibiotics by OmpF porin channels.

Science.gov (United States)

Phan, Katherine; Ferenci, Thomas

2017-06-01

The trade-off relationship between antibiotic exclusion and nutrient access across the Gram-negative outer membrane is determined by structural constraints in porin channels. The precise nutritional cost of exclusion is unknown for different antibiotics, as are the shapes of the nutrition-susceptibility trade-off. Using a library of 10 engineered isogenic Escherichia coli strains with structural modifications of OmpF porin expressed at a constant level, susceptibilities were measured for nine antibiotics and the nutritional fitness costs estimated by competitions in chemostats. Different antibiotics exhibited a remarkably varied range of geometries in the nutrition-susceptibility trade-off, including convex, concave and sigmoidal trade-off shapes. The trade-off patterns predict the possibility of adaptations in contributing to antibiotic resistance; exclusion of amoxicillin or trimethoprim in ompF mutants can occur with little loss of fitness whereas kanamycin and streptomycin exclusion has a high cost. Some individual OmpF changes even allow positive correlations (trade-ups), resulting in increased fitness and decreased susceptibility specifically to cephalexin or ciprofloxacin. The surprising plasticity of the nutrition-exclusion relationship means that there are no generalisable rules that apply to decreasing susceptibility for all antibiotics. The protein changes are exquisitely specific in determining nutritional fitness and adaptive outcomes in a structural constraint trade-off.

Mechanistic and quantitative insight into cell surface targeted molecular imaging agent design.

Science.gov (United States)

Zhang, Liang; Bhatnagar, Sumit; Deschenes, Emily; Thurber, Greg M

2016-05-05

Molecular imaging agent design involves simultaneously optimizing multiple probe properties. While several desired characteristics are straightforward, including high affinity and low non-specific background signal, in practice there are quantitative trade-offs between these properties. These include plasma clearance, where fast clearance lowers background signal but can reduce target uptake, and binding, where high affinity compounds sometimes suffer from lower stability or increased non-specific interactions. Further complicating probe development, many of the optimal parameters vary depending on both target tissue and imaging agent properties, making empirical approaches or previous experience difficult to translate. Here, we focus on low molecular weight compounds targeting extracellular receptors, which have some of the highest contrast values for imaging agents. We use a mechanistic approach to provide a quantitative framework for weighing trade-offs between molecules. Our results show that specific target uptake is well-described by quantitative simulations for a variety of targeting agents, whereas non-specific background signal is more difficult to predict. Two in vitro experimental methods for estimating background signal in vivo are compared - non-specific cellular uptake and plasma protein binding. Together, these data provide a quantitative method to guide probe design and focus animal work for more cost-effective and time-efficient development of molecular imaging agents.

Odor Classification using Agent Technology

Directory of Open Access Journals (Sweden)

Sigeru OMATU

2014-03-01

Full Text Available In order to measure and classify odors, Quartz Crystal Microbalance (QCM can be used. In the present study, seven QCM sensors and three different odors are used. The system has been developed as a virtual organization of agents using an agent platform called PANGEA (Platform for Automatic coNstruction of orGanizations of intElligent Agents. This is a platform for developing open multi-agent systems, specifically those including organizational aspects. The main reason for the use of agents is the scalability of the platform, i.e. the way in which it models the services. The system models functionalities as services inside the agents, or as Service Oriented Approach (SOA architecture compliant services using Web Services. This way the adaptation of the odor classification systems with new algorithms, tools and classification techniques is allowed.

Energy trading

International Nuclear Information System (INIS)

Glachant, J.M.; Kimman, R.; Schweickardt, H.E.

2001-05-01

This document brings together 18 testimonies of experts about energy trading: 1 - the energy trading experience on European deregulated markets: structure of deregulated energy markets in Europe, case study: a two years experience of a power exchange in western Europe, case study: European energy exchanges (experience of spot and future trading), case study: risk management on energy deregulated markets; 2 - the trading activity environment and realities in France: the French electrical law and the purchase for resale, experience feedback: status after 3 months of trading in France (the first experience of a French producer), the access to the power transportation network, which legal constraints for trading in France, the access of eligible clients to the French power market, conditions of implementation of a power exchange market in France, which real trading possibilities in France for producers and self-producers in the legal frame, case study: the role of trading in the company (main part or link to process), convergence of gas and electricity markets, gas-electricity trading: which pricing models; 3 - risk management and use of new technologies potentiality, the results outside the French borders: case study: what differences between the European and US markets, prices volatility and commodity risk management: towards the on-line trading, role and developments of E-business in energy trading, how to simplify trade in a liberalized market. (J.S.)

International trade law perspectives on paperless trade and inclusive digital trade

OpenAIRE

Mitchell, Andrew D.; Mishra, Neha

2017-01-01

Cross-border paperless trade is increasingly important to generate economic gains in a digitalised economy. Several developing and least developed countries will need to modernise their domestic laws and regulations to facilitate cross-border electronic transmissions, particularly to promote cloud computing and electronic payments. In recent trade agreements, trading partners have committed to deeper and more comprehensive provisions on electronic commerce, including adopting domestic laws on...

Changes in the business model for Spanish fresh tomato trade

International Nuclear Information System (INIS)

Pablo-Valenciano, J. de; Giacinti-Battistuzzi, M.A.; Tassile, T.; García-Azcárate, T.

2017-01-01

The business model applied to the fresh tomato trade from Almería is well known in Spain and abroad. The changes in demand are forcing export companies to change their trade strategies to become or remain competitive. The purpose of this paper is to know the business structure and its export dynamics in addition to the changes in trade strategies made by companies in Almería during the 2009-2013 period. The methodology is based on the Herfindahl-Hirshman index and the foreign trade competitiveness index, whereas the congruence analysis is based on Pearson’s correlation coefficients and the RV coefficient. We have also applied the dual multiple factor analysis to verify changes made to the trade policy in leading businesses between two periods or scenarios. The research shows that export-driven companies behave as a moderately concentrated structure and there is an increase in the number of exporters. The competitiveness map for Almería reveals the sector’s trend with regard to the most important markets. We have verified the changes made to their trade strategy to adjust to changes in foreign trade between the 2008/09 and 2012/13 campaigns. Finally, it can be pointed out that, in the analyzed period, changes in the business model for fresh tomato trade of Almería have not been significant, being its structure of moderate concentration. In addition, the great majority of variations in strategies of companies to adapt to the competitive environment have been made by leading companies.

Changes in the business model for Spanish fresh tomato trade

Energy Technology Data Exchange (ETDEWEB)

Pablo-Valenciano, J. de; Giacinti-Battistuzzi, M.A.; Tassile, T.; García-Azcárate, T.

2017-09-01

The business model applied to the fresh tomato trade from Almería is well known in Spain and abroad. The changes in demand are forcing export companies to change their trade strategies to become or remain competitive. The purpose of this paper is to know the business structure and its export dynamics in addition to the changes in trade strategies made by companies in Almería during the 2009-2013 period. The methodology is based on the Herfindahl-Hirshman index and the foreign trade competitiveness index, whereas the congruence analysis is based on Pearson’s correlation coefficients and the RV coefficient. We have also applied the dual multiple factor analysis to verify changes made to the trade policy in leading businesses between two periods or scenarios. The research shows that export-driven companies behave as a moderately concentrated structure and there is an increase in the number of exporters. The competitiveness map for Almería reveals the sector’s trend with regard to the most important markets. We have verified the changes made to their trade strategy to adjust to changes in foreign trade between the 2008/09 and 2012/13 campaigns. Finally, it can be pointed out that, in the analyzed period, changes in the business model for fresh tomato trade of Almería have not been significant, being its structure of moderate concentration. In addition, the great majority of variations in strategies of companies to adapt to the competitive environment have been made by leading companies.

Financial Super-Markets: Size Matters for Asset Trade.

OpenAIRE

Philippe Martin and Hélène Rey.

2000-01-01

This paper presents a new theoretical framework to analyze financial markets in an international context. We build a two-country macroeconomic model in which agents are risk averse, assets are imperfect substitutes, the number of financial assets is endogenous, and cross-border asset trade entails transaction costs. We show that demand effects have important implications for the link between market size, asset prices and financial market development. These effects are consistent with the exis...

Distributed cooperative H∞ optimal tracking control of MIMO nonlinear multi-agent systems in strict-feedback form via adaptive dynamic programming

Science.gov (United States)

Luy, N. T.

2018-04-01

The design of distributed cooperative H∞ optimal controllers for multi-agent systems is a major challenge when the agents' models are uncertain multi-input and multi-output nonlinear systems in strict-feedback form in the presence of external disturbances. In this paper, first, the distributed cooperative H∞ optimal tracking problem is transformed into controlling the cooperative tracking error dynamics in affine form. Second, control schemes and online algorithms are proposed via adaptive dynamic programming (ADP) and the theory of zero-sum differential graphical games. The schemes use only one neural network (NN) for each agent instead of three from ADP to reduce computational complexity as well as avoid choosing initial NN weights for stabilising controllers. It is shown that despite not using knowledge of cooperative internal dynamics, the proposed algorithms not only approximate values to Nash equilibrium but also guarantee all signals, such as the NN weight approximation errors and the cooperative tracking errors in the closed-loop system, to be uniformly ultimately bounded. Finally, the effectiveness of the proposed method is shown by simulation results of an application to wheeled mobile multi-robot systems.

Explor@ Advisory Agent: Tracing the Student's Trail.

Science.gov (United States)

Lundgren-Cayrol, Karin; Paquette, Gilbert; Miara, Alexis; Bergeron, Frederick; Rivard, Jacques; Rosca, Ioan

This paper presents research and development of an adaptive World Wide Web-based system called Explor@ Advisory Agent, capable of tailoring advice to the individual student's needs, actions, and reactions toward pedagogical events, as well as according to diagnosis of content acquisition. Explor@ Advisory Agent consists of two sub-systems, the…

Multimodal training between agents

DEFF Research Database (Denmark)

Rehm, Matthias

2003-01-01

In the system Locator1, agents are treated as individual and autonomous subjects that are able to adapt to heterogenous user groups. Applying multimodal information from their surroundings (visual and linguistic), they acquire the necessary concepts for a successful interaction. This approach has...

Asset price and trade volume relation in artificial market impacted by value investors

Science.gov (United States)

Tangmongkollert, K.; Suwanna, S.

2016-05-01

The relationship between return and trade volume has been of great interests in a financial market. The appearance of asymmetry in the price-volume relation in the bull and bear market is still unsettled. We present a model of the value investor traders (VIs) in the double auction system, in which agents make trading decision based on the pseudo fundamental price modelled by sawtooth oscillations. We investigate the system by two different time series for the asset fundamental price: one corresponds to the fundamental price in a growing phase; and the other corresponds to that in a declining phase. The simulation results show that the trade volume is proportional to the difference between the market price and the fundamental price, and that there is asymmetry between the buying and selling phases. Furthermore, the selling phase has more significant impact of price on the trade volume than the buying phase.

[Supramolecular Agents for Theranostics].

Science.gov (United States)

Deyev, S M; Lebedenko, E N

2015-01-01

This mini-review summarizes recent data obtained in the process of creation of a versatile module platform suitable for construction of supramolecular theranostic agents. As an example, we consider multifunctional hybrid agents for imaging and elimination of cancer cells. The use of an adapter protein system barnase:barstar for producing targeted multifunctional hybrid structures on the basis of highly specific peptides and mini-antibodies as addressing modules and recombinant proteins and/or nanoparticles of different nature (quantum dots, nanogold, magnetic nanoparticles, nanodiamonds, upconverting nanophosphores, polymer nanoparticles) as agents visualizing and damaging cancer cells is described. New perspectives for creation of selective and highly effective compounds for theranostics and personified medicine are contemplated.

Local Orientation and the Evolution of Foraging: Changes in Decision Making Can Eliminate Evolutionary Trade-offs

Science.gov (United States)

van der Post, Daniel J.; Semmann, Dirk

2011-01-01

Information processing is a major aspect of the evolution of animal behavior. In foraging, responsiveness to local feeding opportunities can generate patterns of behavior which reflect or “recognize patterns” in the environment beyond the perception of individuals. Theory on the evolution of behavior generally neglects such opportunity-based adaptation. Using a spatial individual-based model we study the role of opportunity-based adaptation in the evolution of foraging, and how it depends on local decision making. We compare two model variants which differ in the individual decision making that can evolve (restricted and extended model), and study the evolution of simple foraging behavior in environments where food is distributed either uniformly or in patches. We find that opportunity-based adaptation and the pattern recognition it generates, plays an important role in foraging success, particularly in patchy environments where one of the main challenges is “staying in patches”. In the restricted model this is achieved by genetic adaptation of move and search behavior, in light of a trade-off on within- and between-patch behavior. In the extended model this trade-off does not arise because decision making capabilities allow for differentiated behavioral patterns. As a consequence, it becomes possible for properties of movement to be specialized for detection of patches with more food, a larger scale information processing not present in the restricted model. Our results show that changes in decision making abilities can alter what kinds of pattern recognition are possible, eliminate an evolutionary trade-off and change the adaptive landscape. PMID:21998571

Smart Grid Cost-Emission Unit Commitment via Co-Evolutionary Agents

Directory of Open Access Journals (Sweden)

Xiaohua Zhang

2016-10-01

Full Text Available In this paper, the uncertainty of wind, solar and load; smart charging and discharging of plug-in hybrid electric vehicles (PHEVs to and from various energy sources; and the coordination of wind, solar power, PHEVs and cost-emission are considered in the smart grid unit commitment (UC. First, a multi-scenario simulation is used in which a set of valid scenarios is considered for the uncertainties of wind and solar energy sources and load. Then the UC problem for the set of scenarios is decomposed into the optimization of interactive agents by multi-agent technology. Agents’ action is represented by a genetic algorithm with adaptive crossover and mutation operators. The adaptive co-evolution of agents is reached by adaptive cooperative multipliers. Finally, simulation is implemented on an example of a power system containing thermal units, a wind farm, solar power plants and PHEVs. The results show the effectiveness of the proposed method. Thermal units, wind, solar power and PHEVs are mutually complementarily by the adaptive cooperative mechanism. The adaptive multipliers’ updating strategy can save more computational time and further improve the efficiency.

Additive versus multiplicative trade costs and the gains from trade

DEFF Research Database (Denmark)

Sørensen, Allan

This paper addresses welfare effects from trade liberalization in a heterogeneous-fi…rms trade model including the empirically important per-unit (i.e. additive) trade costs in addition to the conventional iceberg (i.e. multiplicative) and fi…xed trade costs. The novel contribution of the paper...... is the result that the welfare gain for a given increase in trade openness is higher for reductions in per-unit (additive) trade costs than for reductions in iceberg (multiplicative) trade costs. The ranking derives from differences in intra-industry reallocations and in particular from dissimilar impacts...

Financial Super-Markets: Size Matters for Asset Trade

OpenAIRE

Philippe Martin; Helene Rey

2001-01-01

This paper presents a new theoretical framework to analyze=20 financial markets in an international context. We build a two-country=20 macroeconomic model in which agents are risk averse, assets are imperfect=20 substitutes, the number of financial assets is endogenous, and cross-border= =20 asset trade entails transaction costs. We show that demand effects have=20 important implications for the link between market size, asset prices and=20 financial market development. These effects are cons...

Estimating the elasticity of trade: the trade share approach

OpenAIRE

Mauro Lanati

2013-01-01

Recent theoretical work on international trade emphasizes the importance of trade elasticity as the fundamental statistic needed to conduct welfare analysis. Eaton and Kortum (2002) proposed a two-step method to estimate this parameter, where exporter fixed effects are regressed on proxies for technology and wages. Within the same Ricardian model of trade, the trade share provides an alternative source of identication for the elasticity of trade. Following Santos Silva and Tenreyro (2006) bot...

Plurilateral Trade Deals: An Alternative for Multilateral Trade Agreements?

Directory of Open Access Journals (Sweden)

Agnes Ghibuțiu

2016-04-01

Full Text Available While multilateral trade negotiations under the World Trade Organization (WTO continue to be in impasse, plurilateral trade negotiations – i.e. among a group of WTO members – have intensified in recent years, and also recorded a series of concrete results in liberalizing specific sectors of international trade. Hence, there is a widely shared view that plurilateral trade negotiations could be an alternative for the multilateral ones. This paper aims to answer the following questions: What are plurilateral trade agreements? Which are the reasons behind the surge in plurilateral negotiations in recent years? What are the main achievements in liberalizing trade at the plurilateral level? What are the advantages of plurilateral negotiations relative to multilateral ones, and why are they considered an attractive alternative for negotiations at the multilateral level?

MIDAS: a practical Bayesian design for platform trials with molecularly targeted agents.

Science.gov (United States)

Yuan, Ying; Guo, Beibei; Munsell, Mark; Lu, Karen; Jazaeri, Amir

2016-09-30

Recent success of immunotherapy and other targeted therapies in cancer treatment has led to an unprecedented surge in the number of novel therapeutic agents that need to be evaluated in clinical trials. Traditional phase II clinical trial designs were developed for evaluating one candidate treatment at a time and thus not efficient for this task. We propose a Bayesian phase II platform design, the multi-candidate iterative design with adaptive selection (MIDAS), which allows investigators to continuously screen a large number of candidate agents in an efficient and seamless fashion. MIDAS consists of one control arm, which contains a standard therapy as the control, and several experimental arms, which contain the experimental agents. Patients are adaptively randomized to the control and experimental agents based on their estimated efficacy. During the trial, we adaptively drop inefficacious or overly toxic agents and 'graduate' the promising agents from the trial to the next stage of development. Whenever an experimental agent graduates or is dropped, the corresponding arm opens immediately for testing the next available new agent. Simulation studies show that MIDAS substantially outperforms the conventional approach. The proposed design yields a significantly higher probability for identifying the promising agents and dropping the futile agents. In addition, MIDAS requires only one master protocol, which streamlines trial conduct and substantially decreases the overhead burden. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Act locally, trade globally. Emissions trading for climate policy

Energy Technology Data Exchange (ETDEWEB)

none

2005-07-01

Climate policy raises a number of challenges for the energy sector, the most significant being the transition from a high to a low-CO2 energy path in a few decades. Emissions trading has become the instrument of choice to help manage the cost of this transition, whether used at international or at domestic level. Act Locally, Trade Globally, offers an overview of existing trading systems, their mechanisms, and looks into the future of the instrument for limiting greenhouse gas emissions. Are current markets likely to be as efficient as the theory predicts? What is, if any, the role of governments in these markets? Can domestic emissions trading systems be broadened to activities other than large stationary energy uses? Can international emissions trading accommodate potentially diverse types of emissions targets and widely different energy realities across countries? Are there hurdles to linking emissions trading systems based on various design features? Can emissions trading carry the entire burden of climate policy, or will other policy instruments remain necessary? In answering these questions, Act Locally, Trade Globally seeks to provide a complete picture of the future role of emissions trading in climate policy and the energy sector.

The Position of Suitcase Trading in Turkey’s Foreign Trade and Growth-Suitcase Trading Connection

Directory of Open Access Journals (Sweden)

Sinem YAPAR SAÇIK

2013-12-01

Full Text Available Suitcase trading which is defined as a purchasing process of merchandises in a country that is implemented by travelers (nonresidents to sell those merchandises in their own country; it has started to take place in balance of payments of Turkey since 1996. After the collapse of USSR in 1991 Turkey became a net exporter in suitcase trading so the country reached significant figures occasionally. In this paper the position of suitcase trading in Turkey’s foreign trade is analyzed in consideration of statistical indicators. According to the findings acquired from the study, suitcase trading is a significant variable for Turkey to have currency and to close foreign deficits. Suitcase trading and growth connection is also analyzed by econometric method which is co-integration test and the result is affirmative. And also it is found that this connection is unilateral causation from growth towards suitcase trading according to the findings of Granger causality test

Poisson-process generalization for the trading waiting-time distribution in a double-auction mechanism

Science.gov (United States)

Cincotti, Silvano; Ponta, Linda; Raberto, Marco; Scalas, Enrico

2005-05-01

In this paper, empirical analyses and computational experiments are presented on high-frequency data for a double-auction (book) market. Main objective of the paper is to generalize the order waiting time process in order to properly model such empirical evidences. The empirical study is performed on the best bid and best ask data of 7 U.S. financial markets, for 30-stock time series. In particular, statistical properties of trading waiting times have been analyzed and quality of fits is evaluated by suitable statistical tests, i.e., comparing empirical distributions with theoretical models. Starting from the statistical studies on real data, attention has been focused on the reproducibility of such results in an artificial market. The computational experiments have been performed within the Genoa Artificial Stock Market. In the market model, heterogeneous agents trade one risky asset in exchange for cash. Agents have zero intelligence and issue random limit or market orders depending on their budget constraints. The price is cleared by means of a limit order book. The order generation is modelled with a renewal process. Based on empirical trading estimation, the distribution of waiting times between two consecutive orders is modelled by a mixture of exponential processes. Results show that the empirical waiting-time distribution can be considered as a generalization of a Poisson process. Moreover, the renewal process can approximate real data and implementation on the artificial stocks market can reproduce the trading activity in a realistic way.

The ASEAN Free Trade Agreement: impact on trade flows and external trade barriers

OpenAIRE

Hector Calvo-Pardo; Caroline Freund; Emanuel Ornelas

2009-01-01

Using detailed data on trade and tariffs from 1992-2007, the authors examine how the ASEAN Free Trade Agreement has affected trade with nonmembers and external tariffs facing nonmembers. First, the paper examines the effect of preferential and external tariff reduction on import growth from ASEAN insiders and outsiders across HS 6-digit industries. The analysis finds no evidence that prefe...

The mobile agent rendezvous problem in the ring

CERN Document Server

Kranakis, Evangelos; Marcou, Euripides

2010-01-01

Mobile agent computing is being used in fields as diverse as artificial intelligence, computational economics and robotics. Agents' ability to adapt dynamically and execute asynchronously and autonomously brings potential advantages in terms of fault-tolerance, flexibility and simplicity. This monograph focuses on studying mobile agents as modelled in distributed systems research and in particular within the framework of research performed in the distributed algorithms community. It studies the fundamental question of how to achieve rendezvous, the gathering of two or more agents at the same n

Synergies, Conflicts, and Trade-offs of C40 Cities Adaptation Strategies

DEFF Research Database (Denmark)

Driscoll, Patrick Arthur; De Rosa, Michele; Lehmann, Martin

2013-01-01

There is a growing body of literature in the field of urban climate change adaptation planning that indicate a need to address climate change planning measures from a more holistic sustainable development perspective. This paper presents the findings from a recently completed study that indicates...... there remain significant unresolved tensions between the development pathways and the climate change adaptation strategies of the 58 cities within the C40 Cities Climate Leadership Group....

Trade Facilitation Provisions in Regional Trade Agreements: Discriminatory or Non-discriminatory?

Directory of Open Access Journals (Sweden)

Innwon Park

2016-12-01

Full Text Available The RTAs with trade facilitation provisions have been expected to generate a larger net trade-creating effect and complement the discriminatory feature of RTAs but have yet to be empirically proven. Recognizing the limitations of existing studies, we conducted a quantitative analysis on the effects of RTAs with and without trade facilitation provisions on both intra- and extra-bloc trade by using a modified gravity equation. We applied the Poisson Pseudo-Maximum Likelihood (PPML estimation with time varying exporter and importer fixed effect method to panel data consisting of 45,770 country pairs covering 170 countries for 2000-2010. We found that the trade facilitation provisions in existing RTAs are non-discriminatory by generating more intra- and extra-bloc trade in general. In particular, we found that the trade effects of RTAs in the APEC region are much stronger than the general case covering all RTAs in the world. In addition, as we control the trade effect of a country's trade facilitation, which is ranked by the World Bank's logistic performance index, RTAs consisting of trade facilitation provisions are discriminatory for trade in final goods and non-discriminatory for trade in intermediate goods. Overall, we endeavor to "explain," instead of "hypothesizing," why most of the recent RTAs contain trade facilitation provisions, especially in light of the deepening regional interdependence through trade in parts and components under global value chains and support the necessity of multilateralizing RTAs by implementing non-discriminatory trade facilitation provisions.

Econophysics of agent-based models

CERN Document Server

Aoyama, Hideaki; Chakrabarti, Bikas; Chakraborti, Anirban; Ghosh, Asim

2014-01-01

The primary goal of this book is to present the research findings and conclusions of physicists, economists, mathematicians and financial engineers working in the field of "Econophysics" who have undertaken agent-based modelling, comparison with empirical studies and related investigations. Most standard economic models assume the existence of the representative agent, who is “perfectly rational” and applies the utility maximization principle when taking action. One reason for this is the desire to keep models mathematically tractable: no tools are available to economists for solving non-linear models of heterogeneous adaptive agents without explicit optimization. In contrast, multi-agent models, which originated from statistical physics considerations, allow us to go beyond the prototype theories of traditional economics involving the representative agent. This book is based on the Econophys-Kolkata VII Workshop, at which many such modelling efforts were presented. In the book, leading researchers in the...

Heterogeneous Agent Model with Memory and Asset Price Behaviour

Czech Academy of Sciences Publication Activity Database

Vošvrda, Miloslav; Vácha, Lukáš

2003-01-01

Roč. 12, č. 2 (2003), s. 155-168 ISSN 1210-0455 R&D Projects: GA ČR GA402/00/0439; GA ČR GA402/01/0034 Institutional research plan: CEZ:AV0Z1075907 Keywords : efficient markets hypothesis * technical trading rules * heterogeneous agent model with memory and learning Subject RIV: AH - Economics

Learning from induced changes in opponent (re)actions in multi-agent games

NARCIS (Netherlands)

P.J. 't Hoen (Pieter Jan); S.M. Bohte (Sander); J.A. La Poutré (Han)

2005-01-01

textabstractMulti-agent learning is a growing area of research. An important topic is to formulate how an agent can learn a good policy in the face of adaptive, competitive opponents. Most research has focused on extensions of single agent learning techniques originally designed for agents in more

The Cost of Technical Trading Rules in the Forex Market: A Utility-based Evaluation

NARCIS (Netherlands)

H.D.R. Dewachter (Hans); M. Lyrio (Marco)

2003-01-01

textabstractWe compute the opportunity cost for rational risk averse agents of using technical trading rules in the foreign exchange rate market. Our purpose is to investigate whether these rules can be interpreted as near-rational investment strategies for rational investors. We analyze four

Molecular signal for induction of the adaptive response to alkylating agents in E. coli

Energy Technology Data Exchange (ETDEWEB)

Lindahl, T.; Sedgwick, B.; Teo, I.; Kilpatrick, M.; McCarthy, T.; Hughes, S.

1986-05-01

Exposure of E. coli to simple alkylating agents such as methylnitrosourea causes the induction of at least three DNA repair functions, which are under the control of the ada gene. The intracellular signal for switching on the response has been identified as one of the two stereoisomers of methyl phosphotriesters generated in DNA by alkylation. The methyl group is transferred from the phosphotriester moiety to a specific cysteine residue within the regulatory Ada protein in a self-methylation reaction. This protein also corrects the mutagenic lesion O/sup 6/-methylguanine by transfer of its methyl group to a separate cysteine residue in the Ada protein. Methylation of the protein from repair of a DNA phosphotriester residue, but not from O/sup 6/-methylguanine, converts it to an activator of transcription of genes involved in the adaptive response. The activated form of the Ada protein enhances transcription by binding specifically to a sequence d(AAA--AAAGCGCA), located immediately upstream of the RNA polymerase binding site in relevant promoter regions.

Evolution of hemostatic agents in surgical practice

Directory of Open Access Journals (Sweden)

Chandru P Sundaram

2010-01-01

Conclusions : A review of the evolution of topical hemostatic agents highlights opportunities for potential novel research. Fibrin sealants may have the most opportunity for advancement, and understanding the history of these products is useful. With the drive in urology for minimally invasive surgical techniques, adaptation of topical hemostatic agents to this surgical approach would be valuable and offers an opportunity for novel contributions.

An assessment of the impact of climate adaptation measures to reduce flood risk on ecosystem services.

Science.gov (United States)

Verburg, Peter H; Koomen, Eric; Hilferink, Maarten; Pérez-Soba, Marta; Lesschen, Jan Peter

Measures of climate change adaptation often involve modification of land use and land use planning practices. Such changes in land use affect the provision of various ecosystem goods and services. Therefore, it is likely that adaptation measures may result in synergies and trade-offs between a range of ecosystems goods and services. An integrative land use modelling approach is presented to assess such impacts for the European Union. A reference scenario accounts for current trends in global drivers and includes a number of important policy developments that correspond to on-going changes in European policies. The reference scenario is compared to a policy scenario in which a range of measures is implemented to regulate flood risk and protect soils under conditions of climate change. The impacts of the simulated land use dynamics are assessed for four key indicators of ecosystem service provision: flood risk, carbon sequestration, habitat connectivity and biodiversity. The results indicate a large spatial variation in the consequences of the adaptation measures on the provisioning of ecosystem services. Synergies are frequently observed at the location of the measures itself, whereas trade-offs are found at other locations. Reducing land use intensity in specific parts of the catchment may lead to increased pressure in other regions, resulting in trade-offs. Consequently, when aggregating the results to larger spatial scales the positive and negative impacts may be off-set, indicating the need for detailed spatial assessments. The modelled results indicate that for a careful planning and evaluation of adaptation measures it is needed to consider the trade-offs accounting for the negative effects of a measure at locations distant from the actual measure. Integrated land use modelling can help land use planning in such complex trade-off evaluation by providing evidence on synergies and trade-offs between ecosystem services, different policy fields and societal

The Supply of Trade Credit by Brazilian Publicly Traded Firms

Directory of Open Access Journals (Sweden)

Rafael Felipe Schiozer

2011-12-01

Full Text Available This paper investigates the determinants of trade credit supply by Brazilian publicly traded companies between the years of 2005 and 2008. International literature (both theoretical and empirical documents that the main determinants of trade credit supply are the size of the firm and the size of its debt. Both indicate that the availability of resources to the firm is an important factor for the supply of trade credit. In addition, the literature confirms strategic uses of trade credit such as those for price discrimination purposes. The results obtained using a sample of 157 Brazilian companies do not support that size and indebtedness are relevant determinants for trade credit supply, but they confirm the supply of trade credit as a strategic tool for the firms. Additionally we observed a significant decrease in trade credit supply in 2008, the year in which a severe international financial crisis took place.

Optimal trading of plug-in electric vehicle aggregation agents in a market environment for sustainability

International Nuclear Information System (INIS)

Shafie-khah, M.; Heydarian-Forushani, E.; Golshan, M.E.H.; Siano, P.; Moghaddam, M.P.; Sheikh-El-Eslami, M.K.; Catalão, J.P.S.

2016-01-01

Highlights: • Proposing a multi-stage stochastic model of a PEV aggregation agent. • Reflecting several uncertainties using a stochastic model and appropriate scenarios. • Updating bids/offers of PEV aggregation agents by taking part in the intraday market. • Taking part in Demand Response eXchange (DRX) markets. - Abstract: Ever since energy sustainability is an emergent concern, Plug-in Electric Vehicles (PEVs) significantly affect the approaching smart grids. Indeed, Demand Response (DR) brings a positive effect on the uncertainties of renewable energy sources, improving market efficiency and enhancing system reliability. This paper proposes a multi-stage stochastic model of a PEV aggregation agent to participate in day-ahead and intraday electricity markets. The stochastic model reflects several uncertainties such as the behaviour of PEV owners, electricity market prices, and activated quantity of reserve by the system operator. For this purpose, appropriate scenarios are utilized to realize the uncertain feature of the problem. Furthermore, in the proposed model, the PEV aggregation agents can update their bids/offers by taking part in the intraday market. To this end, these aggregation agents take part in Demand Response eXchange (DRX) markets designed in the intraday session by employing DR resources. The numerical results show that DR provides a perfect opportunity for PEV aggregation agents to increase the profit. In addition, the results reveal that the PEV aggregation agent not only can increase its profit by participating in the DRX market, but also can become an important player in the mentioned market.

Theory of agent-based market models with controlled levels of greed and anxiety

International Nuclear Information System (INIS)

Papadopoulos, P; Coolen, A C C

2010-01-01

We use generating functional analysis to study minority-game-type market models with generalized strategy valuation updates that control the psychology of agents' actions. The agents' choice between trend-following and contrarian trading, and their vigor in each, depends on the overall state of the market. Even in 'fake history' models, the theory now involves an effective overall bid process (coupled to the effective agent process) which can exhibit profound remanence effects and new phase transitions. For some models the bid process can be solved directly, others require Maxwell-construction-type approximations.

A trade-off between natural and acquired antibody production in a reptile: implications for long-term resistance to disease

Directory of Open Access Journals (Sweden)

Franziska C. Sandmeier

2012-08-01

Vertebrate immune systems are understood to be complex and dynamic, with trade-offs among different physiological components (e.g., innate and adaptive immunity within individuals and among taxonomic lineages. Desert tortoises (Gopherus agassizii immunised with ovalbumin (OVA showed a clear trade-off between levels of natural antibodies (NAbs; innate immune function and the production of acquired antibodies (adaptive immune function. Once initiated, acquired antibody responses included a long-term elevation in antibodies persisting for more than one year. The occurrence of either (a high levels of NAbs or (b long-term elevations of acquired antibodies in individual tortoises suggests that long-term humoral resistance to pathogens may be especially important in this species, as well as in other vertebrates with slow metabolic rates, concomitantly slow primary adaptive immune responses, and long life-spans.

Insider trading

International Nuclear Information System (INIS)

Maslechko, W.S.

1998-01-01

The policy arguments for and against prohibiting insider trading within the petroleum industry are discussed. Legal definitions of all relevant terms (e.g. 'special relationship' 'tippees', 'material facts', material changes' 'generally disclosed' information', 'necessary course of business') are provided. Enforcement of insider trading/tipping prohibitions are also defined. The recommended practice is: do not trade; do not tell or advise; encourage timely disclosure; do not speculate; implement a corporate disclosure and trading policy

Globalization's effects on world agricultural trade, 1960–2050

Science.gov (United States)

Anderson, Kym

2010-01-01

Recent globalization has been characterized by a decline in the costs of cross-border trade in farm and other products. It has been driven primarily by the information and communication technology revolution and—in the case of farm products—by reductions in governmental distortions to agricultural production, consumption and trade. Both have boosted economic growth and reduced poverty globally, especially in Asia. The first but maybe not the second of these drivers will continue in coming decades. World food prices will depend also on whether (and if so by how much) farm productivity growth continues to outpace demand growth and to what extent diets in emerging economies move towards livestock and horticultural products at the expense of staples. Demand in turn will be driven not only by population and income growth, but also by crude oil prices if they remain at current historically high levels, since that will affect biofuel demand. Climate change mitigation policies and adaptation, water market developments and market access standards particularly for transgenic foods will add to future production, price and trade uncertainties. PMID:20713399

Opinion dynamics of learning agents: does seeking consensus lead to disagreement?

International Nuclear Information System (INIS)

Vicente, Renato; Martins, André C R; Caticha, Nestor

2009-01-01

We study opinion dynamics in a population of interacting adaptive agents voting on a set of issues represented by vectors. We consider agents who can classify issues into one of two categories and can arrive at their opinions using an adaptive algorithm. Adaptation comes from learning and the information for the learning process comes from interacting with other neighboring agents and trying to change the internal state in order to concur with their opinions. The change in the internal state is driven by the information contained in the issue and in the opinion of the other agent. We present results in a simple yet rich context where each agent uses a Boolean perceptron to state their opinion. If the update occurs with information asynchronously exchanged among pairs of agents, then the typical case, if the number of issues is kept small, is the evolution into a society torn by the emergence of factions with extreme opposite beliefs. This occurs even when seeking consensus with agents with opposite opinions. If the number of issues is large, the dynamics becomes trapped, the society does not evolve into factions and a distribution of moderate opinions is observed. The synchronous case is technically simpler and is studied by formulating the problem in terms of differential equations that describe the evolution of order parameters that measure the consensus between pairs of agents. We show that for a large number of issues and unidirectional information flow, global consensus is a fixed point; however, the approach to this consensus is glassy for large societies

Opinion dynamics of learning agents: does seeking consensus lead to disagreement?

Science.gov (United States)

Vicente, Renato; Martins, André C. R.; Caticha, Nestor

2009-03-01

We study opinion dynamics in a population of interacting adaptive agents voting on a set of issues represented by vectors. We consider agents who can classify issues into one of two categories and can arrive at their opinions using an adaptive algorithm. Adaptation comes from learning and the information for the learning process comes from interacting with other neighboring agents and trying to change the internal state in order to concur with their opinions. The change in the internal state is driven by the information contained in the issue and in the opinion of the other agent. We present results in a simple yet rich context where each agent uses a Boolean perceptron to state their opinion. If the update occurs with information asynchronously exchanged among pairs of agents, then the typical case, if the number of issues is kept small, is the evolution into a society torn by the emergence of factions with extreme opposite beliefs. This occurs even when seeking consensus with agents with opposite opinions. If the number of issues is large, the dynamics becomes trapped, the society does not evolve into factions and a distribution of moderate opinions is observed. The synchronous case is technically simpler and is studied by formulating the problem in terms of differential equations that describe the evolution of order parameters that measure the consensus between pairs of agents. We show that for a large number of issues and unidirectional information flow, global consensus is a fixed point; however, the approach to this consensus is glassy for large societies.

The Structure of Trade in Genetic Resources: Implications for the International ABS Regime Negotiation

Directory of Open Access Journals (Sweden)

Mikyung Yun

2010-06-01

Full Text Available The intensive exploitation of genetic resources at the international level has led to a negotiation of an international regime on Access and Benefit-Sharing (ABS of genetic resources. Due to lack of systematic data, little is known about the structure of trade in genetic resources to inform the negotiators. This study attempts to shed a greater insight into genetic resources trade in the pharmaceutical sector in Korea, mainly relying on interviews of industry practitioners and scientists in related fields. The study finds that Korea is mainly a genetic resource importer, but that pharmaceutical firms rarely carry out bioprospecting directly, relying on semi-processed biochemicals imports trough agents. Therefore, the impact of the to-be negotiated international ABS negotiation will be larger if derivatives are included in its scope. However, the general impact on the economy as a whole would be small, given the small share of genetic resources trade compared to total trade volumes.

Additive versus Multiplicative Trade Costs and the Gains from Trade Liberalizations

DEFF Research Database (Denmark)

Sørensen, Allan

2014-01-01

This paper addresses welfare e¤ects from trade liberalization in a Melitz (2003) heterogeneous-…rms trade model including the empirically important per-unit (i.e. additive) trade costs in addition to the conventional iceberg (i.e. multiplicative) and …xed trade costs. The novel contribution...... of the pa- per is the result that the welfare gain for a given increase in trade openness is higher for reductions in per-unit (additive) trade costs than for reductions in iceberg (multiplicative) trade costs. The ranking derives from di¤erences in intra-industry reallocations and in particular from...

BROA: An agent-based model to recommend relevant Learning Objects from Repository Federations adapted to learner profile

Directory of Open Access Journals (Sweden)

Paula A. Rodríguez

2013-03-01

Full Text Available Learning Objects (LOs are distinguished from traditional educational resources for their easy and quickly availability through Web-based repositories, from which they are accessed through their metadata. In addition, having a user profile allows an educational recommender system to help the learner to find the most relevant LOs based on their needs and preferences. The aim of this paper is to propose an agent-based model so-called BROA to recommend relevant LOs recovered from Repository Federations as well as LOs adapted to learner profile. The model proposed uses both role and service models of GAIA methodology, and the analysis models of the MAS-CommonKADS methodology. A prototype was built based on this model and validated to obtain some assessing results that are finally presented.

Trade Policy Preferences and the Factor Content of Trade

DEFF Research Database (Denmark)

Jäkel, Ina Charlotte; Smolka, Marcel

demonstrate that the factor price changes induced by trade policy are negatively correlated with the factor content of free trade (and therefore factor abundance). Using large-scale international survey data, we test whether these predicted distributional effects are reflected in the trade policy preferences...... of workers with different labor market skills. In order to isolate the effects of factor abundance from other skill-related confounding factors, we employ a within-skill-group estimator that exploits the cross-country variation in the factor content of free trade. In line with theory, the data show......This paper provides a theoretical and empirical analysis of public opinion towards free trade, investigating cleavages both between and within countries. We study the distributional effects of trade policy in a neoclassical economy with not just two, but many input factors in production. We...

Free trade or just trade? The world trade organisation, human rights ...

African Journals Online (AJOL)

The author critically examines the role of the World Trade Organisation (WTO). In recent years, it is noted, the organisation's agenda of trade liberalisation, its perceived lack of accountability and insensitivity to human rights have attracted intense criticism. It has been asserted that provisions of WTO agreements concerning ...

Trade structure, trade mode and the urban-rural income gap in China

Directory of Open Access Journals (Sweden)

Hao Wei

2013-05-01

Full Text Available This paper analyses the effect of foreign trade in China on the urban-rural income gap from certain angles including trade scale, trade structure and trade mode at the national and provincial levels. The empirical results indicate that, from the perspective of trade scale, the export and import in the eastern and national regions have an expansion effect on the urban-rural income gap, and, in the central regions, they have a reduction effect. Furthermore, export in the western regions has a reduction effect while import in these regions did not have a significant effect. From the perspective of trade structure, the trade of high-tech products and labour-intensive products in the national and eastern regions has an expansion effect, and the trade of the above-mentioned products in the central regions has a reduction effect. The trade of labour-intensive products in the western regions has a reduction effect, and that of high-tech products an expansion effect. From the perspective of trade mode, processing trade and general trade in the national and eastern regions have an expansion effect, while in the central regions they have a reduction effect. General trade in the western regions would expand the urban-rural income gap, and processing trade does not have a significant effect. Consequently, when the South African Government is working out trade multiplicative and corresponding policy, they should consider the development of foreign trade and should pay attention to the labour market structure.

On financial markets trading

Science.gov (United States)

Matassini, Lorenzo; Franci, Fabio

2001-01-01

Starting from the observation of the real trading activity, we propose a model of a stockmarket simulating all the typical phases taking place in a stock exchange. We show that there is no need of several classes of agents once one has introduced realistic constraints in order to confine money, time, gain and loss within an appropriate range. The main ingredients are local and global coupling, randomness, Zipf distribution of resources and price formation when inserting an order. The simulation starts with the initial public offer and comprises the broadcasting of news/advertisements and the building of the book, where all the selling and buying orders are stored. The model is able to reproduce fat tails and clustered volatility, the two most significant characteristics of a real stockmarket, being driven by very intuitive parameters.

Model-based design of adaptive embedded systems

CERN Document Server

Hamberg, Roelof; Reckers, Frans; Verriet, Jacques

2013-01-01

Today’s embedded systems have to operate in a wide variety of dynamically changing environmental circumstances. Adaptivity, the ability of a system to autonomously adapt itself, is a means to optimise a system’s behaviour to accommodate changes in its environment. It involves making in-product trade-offs between system qualities at system level. The main challenge in the development of adaptive systems is keeping control of the intrinsic complexity of such systems while working with multi-disciplinary teams to create different parts of the system. Model-Based Development of Adaptive Embedded Systems focuses on the development of adaptive embedded systems both from an architectural and methodological point of view. It describes architectural solution patterns for adaptive systems and state-of-the-art model-based methods and techniques to support adaptive system development. In particular, the book describes the outcome of the Octopus project, a cooperation of a multi-disciplinary team of academic and indus...

Considerations on National and Union Regulations of Work through a Temporary Employment Agent

Directory of Open Access Journals (Sweden)

Carmen Constantina Nenu

2013-05-01

Full Text Available The necessity to adapt the organizational structure of economic operators to the competitive European market requirements has imposed measures that have also influenced labor relations. The permanent and full-time employment relationship has been largely replaced by other types of more flexible labor relationships: temporary employment, part-time work. working from home and temporary assignment through an employment agency. All these types of work relationships are characterized by a decrease of guarantees for the employee and by a reduction of trade union power. Thus, they are considered atypical work relationships. The need to make the flexibility of labor relationships compatible with the protection of employees” rights has been a challenge that must be faced by social policies and also by labor law. In this context, the use of a temporary employment agent has been a tool for flexible working relationships both with the economic operators and within the labor market as a whole. The importane and role of this type of working relationship has, therefore, acquired significant legal, economic and social dimensions, which this study intends to analyze. In a European economy hit by the jobs crisis, reliance on work through a temporary employment agent can be a way to reduce unemployment. This happens only if the temporary workers benefit from legal protection and equal treatment as permanent employees.

A Watershed-Scale Agent-Based Model Incorporating Agent Learning and Interaction of Farmers' Decisions Subject to Carbon and Miscanthus Prices

Science.gov (United States)

Ng, T.; Eheart, J.; Cai, X.; Braden, J. B.

2010-12-01

Agricultural watersheds are coupled human-natural systems where the land use decisions of human agents (farmers) affect surface water quality, and in turn, are affected by the weather and yields. The reliable modeling of such systems requires an approach that considers both the human and natural aspects. Agent-based modeling (ABM), representing the human aspect, coupled with hydrologic modeling, representing the natural aspect, is one such approach. ABM is a relatively new modeling paradigm that formulates the system from the perspectives of the individual agents, i.e., each agent is modeled as a discrete autonomous entity with distinct goals and actions. The primary objective of this study is to demonstrate the applicability of this approach to agricultural watershed management. This is done using a semi-hypothetical case study of farmers in the Salt Creek watershed in East-Central Illinois under the influence markets for carbon and second-generation bioenergy crop (specifically, miscanthus). An agent-based model of the system is developed and linked to a hydrologic model of the watershed. The former is based on fundamental economic and mathematical programming principles, while the latter is based on the Soil and Water Assessment Tool (SWAT). Carbon and second-generation bioenergy crop markets are of interest here due to climate change and energy independence concerns. The agent-based model is applied to fifty hypothetical heterogeneous farmers. The farmers' decisions depend on their perceptions of future conditions. Those perceptions are updated, according to a pre-defined algorithm, as the farmers make new observations of prices, costs, yields and the weather with time. The perceptions are also updated as the farmers interact with each other as they share new information on initially unfamiliar activities (e.g., carbon trading, miscanthus cultivation). The updating algorithm is set differently for different farmers such that each is unique in his processing of

The hidden hyperbolic geometry of international trade: World Trade Atlas 1870-2013.

Science.gov (United States)

García-Pérez, Guillermo; Boguñá, Marián; Allard, Antoine; Serrano, M Ángeles

2016-09-16

Here, we present the World Trade Atlas 1870-2013, a collection of annual world trade maps in which distance combines economic size and the different dimensions that affect international trade beyond mere geography. Trade distances, based on a gravity model predicting the existence of significant trade channels, are such that the closer countries are in trade space, the greater their chance of becoming connected. The atlas provides us with information regarding the long-term evolution of the international trade system and demonstrates that, in terms of trade, the world is not flat but hyperbolic, as a reflection of its complex architecture. The departure from flatness has been increasing since World War I, meaning that differences in trade distances are growing and trade networks are becoming more hierarchical. Smaller-scale economies are moving away from other countries except for the largest economies; meanwhile those large economies are increasing their chances of becoming connected worldwide. At the same time, Preferential Trade Agreements do not fit in perfectly with natural communities within the trade space and have not necessarily reduced internal trade barriers. We discuss an interpretation in terms of globalization, hierarchization, and localization; three simultaneous forces that shape the international trade system.

Phenotypic plasticity and local adaptation in two extreme ...

African Journals Online (AJOL)

Principal coordinate analysis (PCoA) of allozymes revealed little genetic overlap among populations. Keywords: allozyme, genotype×environment interaction, genetic variation, local adaptation, reaction norms, starch gel electrophoresis, trade-off. African Journal of Range & Forage Science 2008, 25(3): 121–130 ...

Socially intelligent autonomous agents that learn from human reward

NARCIS (Netherlands)

Li, Guangliang

2016-01-01

In the future, autonomous agents will operate in human inhabited environments in many real world applications and become an integral part of human’s daily lives. Therefore, when autonomous agents enter into the real world, they need to adapt to many novel, dynamic and complex situations that cannot

Adaptive cyclically dominating game on co-evolving networks: numerical and analytic results

Science.gov (United States)

Choi, Chi Wun; Xu, Chen; Hui, Pak Ming

2017-10-01

A co-evolving and adaptive Rock (R)-Paper (P)-Scissors (S) game (ARPS) in which an agent uses one of three cyclically dominating strategies is proposed and studied numerically and analytically. An agent takes adaptive actions to achieve a neighborhood to his advantage by rewiring a dissatisfying link with a probability p or switching strategy with a probability 1 - p. Numerical results revealed two phases in the steady state. An active phase for p pc has three separate clusters of agents using only R, P, and S, respectively with terminated adaptive actions. A mean-field theory based on the link densities in co-evolving network is formulated and the trinomial closure scheme is applied to obtain analytical solutions. The analytic results agree with simulation results on ARPS well. In addition, the different probabilities of winning, losing, and drawing a game among the agents are identified as the origin of the small discrepancy between analytic and simulation results. As a result of the adaptive actions, agents of higher degrees are often those being taken advantage of. Agents with a smaller (larger) degree than the mean degree have a higher (smaller) probability of winning than losing. The results are informative for future attempts on formulating more accurate theories.

Agent-based approach for generation of a money-centered star network

Science.gov (United States)

Yang, Jae-Suk; Kwon, Okyu; Jung, Woo-Sung; Kim, In-mook

2008-09-01

The history of trade is a progression from a pure barter system. A medium of exchange emerges autonomously in the market, a position currently occupied by money. We investigate an agent-based computational economics model consisting of interacting agents considering distinguishable properties of commodities which represent salability. We also analyze the properties of the commodity network using a spanning tree. We find that the “storage fee” is more crucial than “demand” in determining which commodity is used as a medium of exchange.

THE MAIN OPERATIONS OF REORGANIZATION THROUGH MERGERS OF TRADING COMPANIES

Directory of Open Access Journals (Sweden)

Alexandra-Gabriela Rolea

2013-11-01

Full Text Available Notwithstanding the optimistic forecasts issued by experts a couple of years ago, the economic predicaments of the European Union’s member states, including Romania, are far from being settled. The extension of the economic and financial dowturn, the continuing process of globalization and the financial markets’ volatility have imposed an unparalleled flexibility upon the economic agents, in that the amount of mergers and acquisitions has risen at a both national and international level. This background calls for a detailed but nonetheless approachable study of the reorganization of the trading companies though mergers, aimed mainly at the business environment. In order to reach the aforementioned objectives, the theoretical endeavor seeks to explore the relevant legal provisions, including the European Directives. The juridical and accounting operations of mergers, their legal consequences and concrete implications on the activity of the trading companies will also be analysed. Some particular approaches embraced by the legal practice are to be presented, as in Romania mergers are submitted to the control of the court. The study will have a positive impact on the economic agents, who are fostered to conclude this type of restructuring, by altering the line of thought shaped a few years ago, according to which mergers are difficult, isolated and sometimes even unacceptable operations.

Insider trading under trading ban regulation in China’s A-share market

Directory of Open Access Journals (Sweden)

Chafen Zhu

2015-09-01

Full Text Available This study examines the effects of China’s 2008 trading ban regulation on the insider trading of large shareholders in China’s A-share market. It finds no evidence of insider trading during the ban period (one month before the announcement of a financial report, due to high regulation risk. However, the ban only constrains the profitability of insider trades during the ban period, while trades outside it remain highly profitable. Informed insider trading before the ban period is 2.83 times more profitable than uninformed trading. The regulation has changed insider trading patterns, but has been ineffective in preventing insider trading by large shareholders due to rigid administrative supervision and a lack of civil litigation and flexible market monitoring. This study enhances understanding of large shareholders’ trading behavior and has important implications for regulators.

Global adaptation in networks of selfish components: emergent associative memory at the system scale.

Science.gov (United States)

Watson, Richard A; Mills, Rob; Buckley, C L

2011-01-01

In some circumstances complex adaptive systems composed of numerous self-interested agents can self-organize into structures that enhance global adaptation, efficiency, or function. However, the general conditions for such an outcome are poorly understood and present a fundamental open question for domains as varied as ecology, sociology, economics, organismic biology, and technological infrastructure design. In contrast, sufficient conditions for artificial neural networks to form structures that perform collective computational processes such as associative memory/recall, classification, generalization, and optimization are well understood. Such global functions within a single agent or organism are not wholly surprising, since the mechanisms (e.g., Hebbian learning) that create these neural organizations may be selected for this purpose; but agents in a multi-agent system have no obvious reason to adhere to such a structuring protocol or produce such global behaviors when acting from individual self-interest. However, Hebbian learning is actually a very simple and fully distributed habituation or positive feedback principle. Here we show that when self-interested agents can modify how they are affected by other agents (e.g., when they can influence which other agents they interact with), then, in adapting these inter-agent relationships to maximize their own utility, they will necessarily alter them in a manner homologous with Hebbian learning. Multi-agent systems with adaptable relationships will thereby exhibit the same system-level behaviors as neural networks under Hebbian learning. For example, improved global efficiency in multi-agent systems can be explained by the inherent ability of associative memory to generalize by idealizing stored patterns and/or creating new combinations of subpatterns. Thus distributed multi-agent systems can spontaneously exhibit adaptive global behaviors in the same sense, and by the same mechanism, as with the organizational

Redirecting International Trade

DEFF Research Database (Denmark)

Kokko, Ari; Söderlund, Bengt; Tingvall, Patrik Gustavsson

2014-01-01

The global financial crisis has contributed to the redirection of trade towards new markets outside the OECD area, where both demand patterns and the institutional environment differ from those in the OECD. This study provides an empirical examination of the consequences of this shift, based......-specific investments are particularly difficult to redirect towards markets with weak institutions....... on Swedish firm-level trade data. Results suggest that weak institutions hamper trade and reduce the length of trade relations, especially for small firms. Trade in industries that are characterized by a high frequency of trade conflicts and where transactions require extensive relationship...

Redirecting International Trade

DEFF Research Database (Denmark)

Kokko, Ari; Söderlund, Bengt; Tingvall, Patrik Gustavsson

The global financial crisis has accelerated the redirection of trade towards new markets, outside the OECD area, where both demand patterns and the institutional environment differ from those in the OECD. This study provides an empirical examination of the consequences of this shift. Results...... difficult to redirect towards markets with weak institutions....... suggest that weak institutions hamper trade and reduces the length of trade relations, especially for small firms. Furthermore, trade in industries that are characterized by a high degree of trade conflicts and that requires extensive relationship specific investments for trade to occur are comparatively...

Organizational coordination and costly communication with boundedly rational agents

DEFF Research Database (Denmark)

Dietrichson, Jens; Jochem, Torsten

How does costly communication affect organizational coordination? This paper develops a model of costly communication based on the weakest-link game and boundedly rational agents. Solving for the stochastically stable states, we find that communication increases the possibilities for efficient...... coordination compared to a setting where agents cannot communicate. But as agents face a trade-off between lowering the strategic uncertainty for the group and the costs of communication, the least efficient state is still the unique stochastically stable one for many parameter values. Simulations show...... that this is not just a long run phenomena, the stochastically stable state is the most frequent outcome also in the short run. Making communication mandatory induces efficient coordination, whereas letting a team leader handle communication increases efficiency when the leader expects others to follow and has enough...

The effects of competing trade regimes on bilateral trade flows: case of Serbia

Directory of Open Access Journals (Sweden)

Predrag Bjelić

2012-12-01

Full Text Available The aim of this paper is to investigate the effects of competing trade regimes on Serbian trade with its most significant (traditional partners, like European Union and CEFTA 2006 signatories, and other untraditional trade partners with favourable trade regime, like the USA. To this end, gravity model with bilateral and time effects is estimated by Hausman-Taylor AR(1 instrumental variable estimator, using panel data on bilateral trade between Serbia and its main trade partners during the period 2001-2010. The results indicate that overall level of development and difference in factor endowments stimulate Serbia’s exports, which is in accordance with theoretical foundation that inter-industry trade is predominant in exports of less developed countries. Moreover, competing trade regimes appear as important determinant of Serbia’s trade relations, whereas additional liberalization of trade regime with the USA as untraditional trade partner, even asymmetrical to Serbia’s favour, cannot divert trade flows from traditional partners in the long-run. This could mean that distance plays more prominent role in bilateral trade than the degree of liberalization of trade regimes in case of Serbia. The result could be due to the contemporaneous effects of trade preferences granted to Serbia by the EU and other CEFTA 2006 signatories, main trading partners of Serbia.

International trade in services: A scoping study of services trade and estimates of benefits from services trade liberalisation

OpenAIRE

Ballingall, John; Stephenson, John

2005-01-01

This is a scoping study. It summarises the dynamics of services trade in the world economy and discusses some of the benefits of services trade liberalisation from a qualitative and quantitative view point. We place particular emphasis on the role and interests of developing and least developed countries in world services trade. The study also provides an overview of services trade in the New Zealand economy, and, in places, highlights aspects of services trade where New Zealand’s interests m...

The economics of optimal adaptation to climate change

Energy Technology Data Exchange (ETDEWEB)

Callaway, J.M.; Ringius, L.

2002-07-01

This paper has set out to provide a consistent theoretical framework for understanding how consumers, producers and factor agents respond to the impacts of climate change, with a primary focus on the production and consumption of, and investment in, market goods and services under competitive conditions. However, we have also pointed out that this theory can be extended to economies where individuals and groups pursue other well-defined objectives, and we have provided some examples that show the consistency in adaptation behaviour between economic terms and those who maximise the objective of household nutrition. We have defined adaptation as the changes that economic agents make in the allocation of resources to consumption, production and investment to offset the effects of weather variability or climate change on their welfare. This definition is broad enough to encompass almost every conceivable kind of adaptation behaviour. Further, we have followed the distinction between adaptation that is autonomous and adaptation actions that are undertaken by governments in the form of adaptation strategies. Autonomous adaptation is adaptation that economic agents will undertake to change, without the assistance of government, to improve their welfare due to incentives that are built into the political economy of a country. Adaptation strategies involve conscious decisions by governments to undertake actions and implement projects to avoid (or benefit from) weather variability and climate change. We show how the extent to which economic activities are adapted to existing climate variability will affect how much autonomous adaptation will need to occur once the pure effect of climate change is taken into account. In this paper we argue that the ability of economic activities to adapt once the pure effect of climate change can be accounted for by the following factors: Presence of well-developed markets for inputs and outputs; Ability and competitiveness to produce

Classification of Franchise Networks in the Retail Trade

Directory of Open Access Journals (Sweden)

Grygorenko Tetyana M.

2016-11-01

Full Text Available The article clarifies the definitions of the concepts of «franchise network», «franchise trade network», «franchise retail network», which is substantiated by the lack of a unified approach to interpretation of these concepts. The classification of franchise networks in the retail trade taking into account peculiarities in the operation of this sub-sector of the market economy is developed; classification attributes are identified and types of franchise retail chains are characterized. The proposed classification of franchise retail networks is adapted to the economic situation in Ukraine and specifics of the national franchise relations. It will facilitate a deeper understanding of the essence of the formation and operation of franchise retail chains and also help Ukrainian entrepreneurs to justify choosing the most suitable for them franchising model and allow to establish such a network with regard to various attributes using a complex approach.

Linked sustainability challenges and trade-offs among fisheries, aquaculture and agriculture.

Science.gov (United States)

Blanchard, Julia L; Watson, Reg A; Fulton, Elizabeth A; Cottrell, Richard S; Nash, Kirsty L; Bryndum-Buchholz, Andrea; Büchner, Matthias; Carozza, David A; Cheung, William W L; Elliott, Joshua; Davidson, Lindsay N K; Dulvy, Nicholas K; Dunne, John P; Eddy, Tyler D; Galbraith, Eric; Lotze, Heike K; Maury, Olivier; Müller, Christoph; Tittensor, Derek P; Jennings, Simon

2017-09-01

Fisheries and aquaculture make a crucial contribution to global food security, nutrition and livelihoods. However, the UN Sustainable Development Goals separate marine and terrestrial food production sectors and ecosystems. To sustainably meet increasing global demands for fish, the interlinkages among goals within and across fisheries, aquaculture and agriculture sectors must be recognized and addressed along with their changing nature. Here, we assess and highlight development challenges for fisheries-dependent countries based on analyses of interactions and trade-offs between goals focusing on food, biodiversity and climate change. We demonstrate that some countries are likely to face double jeopardies in both fisheries and agriculture sectors under climate change. The strategies to mitigate these risks will be context-dependent, and will need to directly address the trade-offs among Sustainable Development Goals, such as halting biodiversity loss and reducing poverty. Countries with low adaptive capacity but increasing demand for food require greater support and capacity building to transition towards reconciling trade-offs. Necessary actions are context-dependent and include effective governance, improved management and conservation, maximizing societal and environmental benefits from trade, increased equitability of distribution and innovation in food production, including continued development of low input and low impact aquaculture.

Theory of agent-based market models with controlled levels of greed and anxiety

Energy Technology Data Exchange (ETDEWEB)

Papadopoulos, P; Coolen, A C C [Department of Mathematics, King' s College London, The Strand, London WC2R 2LS (United Kingdom)], E-mail: panagiotis.2.papadopoulos@kcl.ac.uk, E-mail: ton.coolen@kcl.ac.uk

2010-01-15

We use generating functional analysis to study minority-game-type market models with generalized strategy valuation updates that control the psychology of agents' actions. The agents' choice between trend-following and contrarian trading, and their vigor in each, depends on the overall state of the market. Even in 'fake history' models, the theory now involves an effective overall bid process (coupled to the effective agent process) which can exhibit profound remanence effects and new phase transitions. For some models the bid process can be solved directly, others require Maxwell-construction-type approximations.

Agent-based simulation of electricity markets : a literature review

International Nuclear Information System (INIS)

Sensfuss, F.; Genoese, M.; Genoese, M.; Most, D.

2007-01-01

The electricity sector in Europe and North America is undergoing considerable changes as a result of deregulation, issues related to climate change, and the integration of renewable resources within the electricity grid. This article reviewed agent-based simulation methods of analyzing electricity markets. The paper provided an analysis of research currently being conducted on electricity market designs and examined methods of modelling agent decisions. Methods of coupling long term and short term decisions were also reviewed. Issues related to single and multiple market analysis methods were discussed, as well as different approaches to integrating agent-based models with models of other commodities. The integration of transmission constraints within agent-based models was also discussed, and methods of measuring market efficiency were evaluated. Other topics examined in the paper included approaches to integrating investment decisions, carbon dioxide (CO 2 ) trading, and renewable support schemes. It was concluded that agent-based models serve as a test bed for the electricity sector, and will help to provide insights for future policy decisions. 74 refs., 6 figs

Competing intelligent search agents in global optimization

Energy Technology Data Exchange (ETDEWEB)

Streltsov, S.; Vakili, P. [Boston Univ., MA (United States); Muchnik, I. [Rutgers Univ., Piscataway, NJ (United States)

1996-12-31

In this paper we present a new search methodology that we view as a development of intelligent agent approach to the analysis of complex system. The main idea is to consider search process as a competition mechanism between concurrent adaptive intelligent agents. Agents cooperate in achieving a common search goal and at the same time compete with each other for computational resources. We propose a statistical selection approach to resource allocation between agents that leads to simple and efficient on average index allocation policies. We use global optimization as the most general setting that encompasses many types of search problems, and show how proposed selection policies can be used to improve and combine various global optimization methods.

Local-scale dynamics and local drivers of bushmeat trade.

Science.gov (United States)

Nyaki, Angela; Gray, Steven A; Lepczyk, Christopher A; Skibins, Jeffrey C; Rentsch, Dennis

2014-10-01

Bushmeat management policies are often developed outside the communities in which they are to be implemented. These policies are also routinely designed to be applied uniformly across communities with little regard for variation in social or ecological conditions. We used fuzzy-logic cognitive mapping, a form of participatory modeling, to compare the assumptions driving externally generated bushmeat management policies with perceptions of bushmeat trade dynamics collected from local community members who admitted to being recently engaged in bushmeat trading (e.g., hunters, sellers, consumers). Data were collected during 9 workshops in 4 Tanzanian villages bordering Serengeti National Park. Specifically, we evaluated 9 community-generated models for the presence of the central factors that comprise and drive the bushmeat trade and whether or not models included the same core concepts, relationships, and logical chains of reasoning on which bushmeat conservation policies are commonly based. Across local communities, there was agreement about the most central factors important to understanding the bushmeat trade (e.g., animal recruitment, low income, and scarcity of food crops). These matched policy assumptions. However, the factors perceived to drive social-ecological bushmeat trade dynamics were more diverse and varied considerably across communities (e.g., presence or absence of collaborative law enforcement, increasing human population, market demand, cultural preference). Sensitive conservation issues, such as the bushmeat trade, that require cooperation between communities and outside conservation organizations can benefit from participatory modeling approaches that make local-scale dynamics and conservation policy assumptions explicit. Further, communities' and conservation organizations' perceptions need to be aligned. This can improve success by allowing context appropriate policies to be developed, monitored, and appropriately adapted as new evidence is

Truths and governance for adaptive management

Directory of Open Access Journals (Sweden)

M. Kent. Loftin

2014-06-01

Full Text Available Managing large-scale water resources and ecosystem projects is a never ending job, and success should be measured in terms of achieving desired project performance and not just meeting prescriptive requirements of planning and constructing a project simply on time and within budget. Success is more than studying, planning, designing, or operating projects. It is developing the right plan, getting it implemented, and seeing that it is operated and performs properly. Success requires all of these, and failing any of these results in wasted resources and potential for doing great harm. Adaptive management can help make success possible by providing a means for solving the most complex problems, answering unanswered questions, and, in general, reducing uncertainty. Uncertainties are the greatest threats to project success. Stakeholder support and political will are ultimately essential in achieving project success. Project success is often impossible to achieve if uncertainties persist. Resolving uncertainties quickly and efficiently facilitates the greatest forward progress in the shortest possible time. Uncertainties must be reduced or resolved to a sufficient level, not over-resolved or under-resolved. Over-resolving presents a value trade-off between additional knowledge and the cost of getting it. Under-resolving trades greater risks of failure for cost savings. Resolutional sufficiency varies from uncertainty to uncertainty, and applying risk-based logic is helpful in determining what is sufficient. Adaptive management can bring great efficiency and produce high returns on investment. Project-stopping uncertainties get resolved, and resources are spent wisely. Organizational governance must understand adaptive management and value it. Adequate time and money must be provided. Adaptive management must be integrated into other organizational processes such as project management and project delivery. Integrating adaptive management requires a new

Ambient agents: embedded agents for remote control and monitoring using the PANGEA platform.

Science.gov (United States)

Villarrubia, Gabriel; De Paz, Juan F; Bajo, Javier; Corchado, Juan M

2014-07-31

Ambient intelligence has advanced significantly during the last few years. The incorporation of image processing and artificial intelligence techniques have opened the possibility for such aspects as pattern recognition, thus allowing for a better adaptation of these systems. This study presents a new model of an embedded agent especially designed to be implemented in sensing devices with resource constraints. This new model of an agent is integrated within the PANGEA (Platform for the Automatic Construction of Organiztions of Intelligent Agents) platform, an organizational-based platform, defining a new sensor role in the system and aimed at providing contextual information and interacting with the environment. A case study was developed over the PANGEA platform and designed using different agents and sensors responsible for providing user support at home in the event of incidents or emergencies. The system presented in the case study incorporates agents in Arduino hardware devices with recognition modules and illuminated bands; it also incorporates IP cameras programmed for automatic tracking, which can connect remotely in the event of emergencies. The user wears a bracelet, which contains a simple vibration sensor that can receive notifications about the emergency situation.

Ambient Agents: Embedded Agents for Remote Control and Monitoring Using the PANGEA Platform

Directory of Open Access Journals (Sweden)

Gabriel Villarrubia

2014-07-01

Full Text Available Ambient intelligence has advanced significantly during the last few years. The incorporation of image processing and artificial intelligence techniques have opened the possibility for such aspects as pattern recognition, thus allowing for a better adaptation of these systems. This study presents a new model of an embedded agent especially designed to be implemented in sensing devices with resource constraints. This new model of an agent is integrated within the PANGEA (Platform for the Automatic Construction of Organiztions of Intelligent Agents platform, an organizational-based platform, defining a new sensor role in the system and aimed at providing contextual information and interacting with the environment. A case study was developed over the PANGEA platform and designed using different agents and sensors responsible for providing user support at home in the event of incidents or emergencies. The system presented in the case study incorporates agents in Arduino hardware devices with recognition modules and illuminated bands; it also incorporates IP cameras programmed for automatic tracking, which can connect remotely in the event of emergencies. The user wears a bracelet, which contains a simple vibration sensor that can receive notifications about the emergency situation.

Africa-Asia trade versus Africa's trade with the North: Trends and ...

African Journals Online (AJOL)

Abstract. This study shows that Europe continues to be Africa's major trading partner given the historical relations and long standing trading arrangements between the two. However, evidence also shows that despite maintaining strong trade linkages with Europe, Africa's trade with Asia has been growing at a much faster ...

76 FR 19383 - Certain Stilbenic Optical Brightening Agents From China and Taiwan

Science.gov (United States)

2011-04-07

... Stilbenic Optical Brightening Agents From China and Taiwan AGENCY: United States International Trade... reasonable indication that an industry in the United States is materially injured or threatened with material injury, or the establishment of an industry in the United States is materially retarded, by reason of...

Social Importance Dynamics: A Model for Culturally-Adaptive Agents

NARCIS (Netherlands)

Mascarenhas, S.; Prada, R.; Paiva, A.; Hofstede, G.J.

2013-01-01

The unwritten rules of human cultures greatly affect social behaviour and as such should be considered in the development of socially intelligent agents. So far, there has been a large focus on modeling cultural aspects related to non-verbal behaviour such as gaze or body posture. However, culture

Entropy of international trades

Science.gov (United States)

Oh, Chang-Young; Lee, D.-S.

2017-05-01

The organization of international trades is highly complex under the collective efforts towards economic profits of participating countries given inhomogeneous resources for production. Considering the trade flux as the probability of exporting a product from a country to another, we evaluate the entropy of the world trades in the period 1950-2000. The trade entropy has increased with time, and we show that it is mainly due to the extension of trade partnership. For a given number of trade partners, the mean trade entropy is about 60% of the maximum possible entropy, independent of time, which can be regarded as a characteristic of the trade fluxes' heterogeneity and is shown to be derived from the scaling and functional behaviors of the universal trade-flux distribution. The correlation and time evolution of the individual countries' gross-domestic products and the number of trade partners show that most countries achieved their economic growth partly by extending their trade relationship.

INTERACTION OF TRADE AND FINANCIAL LINKAGES IN THE FREE TRADE ZONES

Directory of Open Access Journals (Sweden)

V. Shevchenko

2014-09-01

Full Text Available Different models of free trade agreements (FTA and free trade zones (FTZ are considered in the article, argued the complex approach to their structures and results under unstable global economic environment. The typology of the free trade zones models and financial linkages types between countries have been developed. Approaches to the results of the free trade zones have been argued. It has been discovered that for the free trade zones of transitional countries the prevailing are tarde flows concentration whereas financial and investment linkages are acting with developed countries. The main directions of increasing of the financial linkages results in the free trade zones have been discovered.

The hidden hyperbolic geometry of international trade: World Trade Atlas 1870–2013

Science.gov (United States)

García-Pérez, Guillermo; Boguñá, Marián; Allard, Antoine; Serrano, M. Ángeles

2016-01-01

Here, we present the World Trade Atlas 1870–2013, a collection of annual world trade maps in which distance combines economic size and the different dimensions that affect international trade beyond mere geography. Trade distances, based on a gravity model predicting the existence of significant trade channels, are such that the closer countries are in trade space, the greater their chance of becoming connected. The atlas provides us with information regarding the long-term evolution of the international trade system and demonstrates that, in terms of trade, the world is not flat but hyperbolic, as a reflection of its complex architecture. The departure from flatness has been increasing since World War I, meaning that differences in trade distances are growing and trade networks are becoming more hierarchical. Smaller-scale economies are moving away from other countries except for the largest economies; meanwhile those large economies are increasing their chances of becoming connected worldwide. At the same time, Preferential Trade Agreements do not fit in perfectly with natural communities within the trade space and have not necessarily reduced internal trade barriers. We discuss an interpretation in terms of globalization, hierarchization, and localization; three simultaneous forces that shape the international trade system. PMID:27633649

Trade in and Valuation of Virtual Water Impacts in a City: A Case Study Of Flagstaff, Arizona

Science.gov (United States)

Rushforth, R.; Ruddell, B. L.

2013-12-01

An increasingly intense component of the global coupled natural and human system (CNH) is the economic trade of various types of resources and the outsourcing of resource impacts between geographically distant economic systems. The human economy's trade arrangements allow specific localities, especially cities, to exceed spatially local resource stock sustainability and footprint constraints, as evidenced in the urban metabolism literature. Each movement or trade of a resource along a network is associated with an embedded or 'virtual' exchange of indirect impacts on the inputs to the production process. The networked trade of embedded resources, therefore, is an essential human adaptation to resource limitations. Using the Embedded Resource Impact Accounting (ERA) framework, we examine the network of embedded water flows created through the trade of goods and services and economic development in Flagstaff, Arizona, and associate these flows with the creation of value in sectors of the economy

The role of wild canids and felids in spreading parasites to dogs and cats in Europe. Part I: Protozoa and tick-borne agents.

Science.gov (United States)

Otranto, Domenico; Cantacessi, Cinzia; Pfeffer, Martin; Dantas-Torres, Filipe; Brianti, Emanuele; Deplazes, Peter; Genchi, Claudio; Guberti, Vittorio; Capelli, Gioia

2015-09-30

Over the last few decades, the world has witnessed radical changes in climate, landscape, and ecosystems. These events, together with other factors such as increasing illegal wildlife trade and changing human behaviour towards wildlife, are resulting into thinning boundaries between wild canids and felids and their domestic counterparts. As a consequence, the epidemiology of diseases caused by a number of infectious agents is undergoing profound readjustements, as pathogens adapt to new hosts and environments. Therefore, there is a risk for diseases of wildlife to spread to domestic carnivores and vice versa, and for zoonotic agents to emerge or re-emerge in human populations. Hence, the identification of the hazards arising from the co-habitation of these species is critical in order to plan and develop adequate control strategies against these pathogens. In the first of this two-part article, we review the role that wild canids and felids may play in the transmission of protozoa and arthropod-borne agents to dogs and cats in Europe, and provide an account of how current and future progress in our understanding of the ecology and epidemiology of parasites, as well as of host-parasite interactions, can assist efforts aimed at controlling parasite transmission. Copyright © 2015 Elsevier B.V. All rights reserved.

Trade in Ideas Performance and Behavioral Properties of Markets in Patents

CERN Document Server

Ullberg, Eskil

2012-01-01

“This is a book for the times. Never have we been more in need of the wealth creation process that can only come from innovations subjected to the trial and error process of selection to decide what among all the experiments can be supported for further trial.” --Vernon L. Smith, Nobel Laureate in Economics 2002, Chapman University   “Eskil Ullberg … departs from the error made by Arrow, an ambitious leap, perhaps, but one that is in this case warranted.  Eskil seeks to explain more of the mechanisms by which property rights, specifically IP, can be sold by inventors to diversify risk and to monetize value.   Using the methodology of experimental economics, he creates a controlled game in which players – rewarded with money returns, to the extent that they follow rules, manage risk, and execute smart trades – reveal how economic agents might generally transact in IP rights traded in organized exchanges. In testing how such trading institutions work, this research seeks to bring Adam Smith’...

Comparative study on current trading system and online trading: the ...

African Journals Online (AJOL)

Comparative study on current trading system and online trading: the case of ... of online trading and factors affecting its feasibility of implementation in ECX. ... The study found that there is significant capacity problem with major skills gap with ...

Sample efficient multiagent learning in the presence of Markovian agents

CERN Document Server

Chakraborty, Doran

2014-01-01

The problem of Multiagent Learning (or MAL) is concerned with the study of how intelligent entities can learn and adapt in the presence of other such entities that are simultaneously adapting. The problem is often studied in the stylized settings provided by repeated matrix games (a.k.a. normal form games). The goal of this book is to develop MAL algorithms for such a setting that achieve a new set of objectives which have not been previously achieved. In particular this book deals with learning in the presence of a new class of agent behavior that has not been studied or modeled before in a MAL context: Markovian agent behavior. Several new challenges arise when interacting with this particular class of agents. The book takes a series of steps towards building completely autonomous learning algorithms that maximize utility while interacting with such agents. Each algorithm is meticulously specified with a thorough formal treatment that elucidates its key theoretical properties.

THE PLACE OF SWITZERLAND IN ROMANIA'S FOREIGN TRADE WITH EFTA DURING 2007-2016

Directory of Open Access Journals (Sweden)

ZAMFIR PAUL BOGDAN

2017-06-01

Full Text Available In this paper it is presented in a synthetic manner the overall evolution of bilateral trade between Romania and Switzerland in the current period of post-accession of our country to EU. Therefore, in order to be successed on this market - to achieve and maintain stable and long-term commercial relations partners, romanian exporters should pay very attention strict implementation of contractual terms, equality rules, conditions and delivery terms and possibly to inform previously on local prices of competing firms. Also it is important to emphasize that the current EU's legal framework regarding trade relations influenced positively the entire climate of bilateral trade between Romanian and Swiss economic agents. At the same time, the bilateral agreements are also applied by Romania in virtue of its quality as member state of EU that automatically adopted and implemented EU legislation, the international treaties and agreements with third countries. Thus, it is noticeable that in post-accession period to the EU, our country in the field of foreign trade with Switzerland applies the legal framework of EU that has as main effect the development of trade conducted between Romanian and Swiss companies. Also, regarding Romania's foreign trade with EFTA states in the current period of post accession to EU it can be noticed a major improvement, due to the three countries of The European Free Trade Association (EFTA except Switzerland is subject to the European Economic Area (EEA Agreement. In this context the elimination of customs duties in trade between our country and EFTA states leads undoubtedly to entry on Romanian market of products with high quality designed to meet the requirements of domestic demand.

Impacts of alternative allowance allocation methods under a cap-and-trade program in power sector

International Nuclear Information System (INIS)

Liu Beibei; He Pan; Zhang Bing; Bi Jun

2012-01-01

Emission trading is considered to be a cost-effective environmental economic instrument for pollution control. However, the policy design of an emission trading program has a decisive impact on its performance. Allowance allocation is one of the most important policy design issues in emission trading, not only for equity but also for policy performance. In this research, an artificial market for sulfur dioxide (SO 2 ) emission trading was constructed by applying an agent-based model. The performance of the Jiangsu SO 2 emission trading market was examined under different allowance allocation methods and transaction costs. The results showed that the market efficiency of emission trading would be affected by the allocation methods when the transaction costs are positive. The auction allowance allocation method was more efficient and had the lowest total emission control costs than the other three allocation methods examined. However, the use of this method will require that power plants pay for all of their allowance, and doing so will increase the production costs of power plants. On the other hand, output-based allowance allocation is the second best method. - Highlights: ► The impact of allowance allocation methods is examined for a cap-and-trade program. ► The market efficiency would be distinct when the transaction costs are positive. ► The auction method would have lowest total emission control costs.

Alleviating inequality in climate policy costs: an integrated perspective on mitigation, damage and adaptation

Science.gov (United States)

De Cian, E.; Hof, A. F.; Marangoni, G.; Tavoni, M.; van Vuuren, D. P.

2016-07-01

Equity considerations play an important role in international climate negotiations. While policy analysis has often focused on equity as it relates to mitigation costs, there are large regional differences in adaptation costs and the level of residual damage. This paper illustrates the relevance of including adaptation and residual damage in equity considerations by determining how the allocation of emission allowances would change to counteract regional differences in total climate costs, defined as the costs of mitigation, adaptation, and residual damage. We compare emission levels resulting from a global carbon tax with two allocations of emission allowances under a global cap-and-trade system: one equating mitigation costs and one equating total climate costs as share of GDP. To account for uncertainties in both mitigation and adaptation, we use a model-comparison approach employing two alternative modeling frameworks with different damage, adaptation cost, and mitigation cost estimates, and look at two different climate goals. Despite the identified model uncertainties, we derive unambiguous results on the change in emission allowance allocation that could lessen the unequal distribution of adaptation costs and residual damages through the financial transfers associated with emission trading.

determinants of intra-industry trade between zambia and it's trading

African Journals Online (AJOL)

Eyerusalem

countries which are relatively similar and produce relatively similar products. IIT arises from the .... trade based on economies of scale, imperfect competition and product differentiation ... with liberalisation, such as the collapse of the manufacturing industries, the country's trade ... Zambia: Diagnostic Trade Integration. Study.

Trade, development and sustainability

DEFF Research Database (Denmark)

Røpke, Inge

1994-01-01

Mainstream economic theory argues that trade, and especially free trade, is beneficial to everyone involved. This fundamental idea ? which has the character of a dogma ? still plays an important role in international discussions on trade issues, notably in relation to development and environment...... be defended in all cases. Especially, the developing countries' benefits from trade have been very dubious. Furthermore, the trading system has contributed to environmental problems in several ways, e.g. generating undervaluation of natural resources, stimulating economic growth with environmental....... The purpose of this article is to critically assess the "free trade dogma" and to investigate the validity of widely used arguments concerning the relations between trade and development and between trade and environment. It is argued that the trading system is not something inherently good, which should...

SHORT CONSIDERATIONS ON THE USE OF TRADE INDICATORS AS TRADEMARKS

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PAUL-GEORGE BUTA

2012-05-01

Full Text Available In today's global marketplace products and services are exchanged internationally not only by large companies wielding a large portfolio of internationally protected trademarks but also by small enterprises and even individuals who have neither the resources nor an interest in the building of such a portfolio. Since they are nonetheless economic agents using either their own or others' trade indicators to indicate the origin and quality of the products and services they provide or simply to advertise them, the present paper addresses some of the issues arising out of that use which is akin to trademark use in what regards said products and services. Special attention is paid to the change in purpose of the trade indicators when used as trademarks and the effects said change causes in the legal protection conferred to those trade indicators. Moreover the possible conflicts between such rights are shortly analyzed and the means for resolution of such conflicts briefly reviewed. Far from being an exhaustive study of the issues raised the present paper aims at identifying these issues and pointing to contentious points to be addressed by future research.

Autonomous sensor manager agents (ASMA)

Science.gov (United States)

Osadciw, Lisa A.

2004-04-01

Autonomous sensor manager agents are presented as an algorithm to perform sensor management within a multisensor fusion network. The design of the hybrid ant system/particle swarm agents is described in detail with some insight into their performance. Although the algorithm is designed for the general sensor management problem, a simulation example involving 2 radar systems is presented. Algorithmic parameters are determined by the size of the region covered by the sensor network, the number of sensors, and the number of parameters to be selected. With straight forward modifications, this algorithm can be adapted for most sensor management problems.

A multi-agent system for coordinating international shipping

Energy Technology Data Exchange (ETDEWEB)

Goldsmith, S.Y.; Phillips, L.R.; Spires, S.V.

1998-05-01

Moving commercial cargo across the US-Mexico border is currently a complex, paper-based, error-prone process that incurs expensive inspections and delays at several ports of entry in the Southwestern US. Improved information handling will dramatically reduce border dwell time, variation in delivery time, and inventories, and will give better control of the shipment process. The Border Trade Facilitation System (BTFS) is an agent-based collaborative work environment that assists geographically distributed commercial and government users with transshipment of goods across the US-Mexico border. Software agents mediate the creation, validation and secure sharing of shipment information and regulatory documentation over the Internet, using the World Wide Web to interface with human actors. Agents are organized into Agencies. Each agency represents a commercial or government agency. Agents perform four specific functions on behalf of their user organizations: (1) agents with domain knowledge elicit commercial and regulatory information from human specialists through forms presented via web browsers; (2) agents mediate information from forms with diverse otologies, copying invariant data from one form to another thereby eliminating the need for duplicate data entry; (3) cohorts of distributed agents coordinate the work flow among the various information providers and they monitor overall progress of the documentation and the location of the shipment to ensure that all regulatory requirements are met prior to arrival at the border; (4) agents provide status information to human actors and attempt to influence them when problems are predicted.

Emission Trading - Effects of the EU directive; Emission Trading - Auswirkungen der EG-Richtlinie

Energy Technology Data Exchange (ETDEWEB)

Meller, E. [Verband der Elektrizitaetswirtschaft -VDEW- e.V., Berlin (Germany)

2004-07-01

The EU-Directive on 'Establishing a Scheme for Greenhouse Gas Emission Allowance Trading within the Community' came into force after it had been published in the Official Journal of the EU. The electricity industry has pursued carefully and constructively the development of this Directive. A number of suggestions were taken into consideration. Currently, the focus - in connection with the adaptation by national legislation - is on the development of a national allocation plan. (orig.) [German] Knapp zwei Jahre nach der Vorlage eines Richtlinien-Entwurfs durch die Europaeische Kommission ist die Richtlinie zur 'Einfuehrung eines EU-weiten Handels mit Treibhausgas-Emissionszertifikaten' in Kraft getreten. Im Mittelpunkt der Umsetzung der Richtlinie in nationales Recht steht die Erstellung eines Nationalen Allokationsplans, dem Kernelement des Zertifikatehandels. Fuer die Stromwirtschaft relevante Aspekte werden eroertert. (orig.)

Agent-Based Models in Social Physics

Science.gov (United States)

Quang, Le Anh; Jung, Nam; Cho, Eun Sung; Choi, Jae Han; Lee, Jae Woo

2018-06-01

We review the agent-based models (ABM) on social physics including econophysics. The ABM consists of agent, system space, and external environment. The agent is autonomous and decides his/her behavior by interacting with the neighbors or the external environment with the rules of behavior. Agents are irrational because they have only limited information when they make decisions. They adapt using learning from past memories. Agents have various attributes and are heterogeneous. ABM is a non-equilibrium complex system that exhibits various emergence phenomena. The social complexity ABM describes human behavioral characteristics. In ABMs of econophysics, we introduce the Sugarscape model and the artificial market models. We review minority games and majority games in ABMs of game theory. Social flow ABM introduces crowding, evacuation, traffic congestion, and pedestrian dynamics. We also review ABM for opinion dynamics and voter model. We discuss features and advantages and disadvantages of Netlogo, Repast, Swarm, and Mason, which are representative platforms for implementing ABM.

Trade Finance during the 2008–9 Trade Collapse : Key Takeaways

OpenAIRE

Chauffour, Jean-Pierre; Malouche, Mariem

2011-01-01

Trade finance matters for trade, and when financial markets and world trade collapsed three years ago, a shortage in trade finance was hailed as a possible culprit. Because of the potential for global repercussions, world leaders called on the international community to act swiftly to avoid a depression. Governments and international institutions intervened to mitigate the impacts of the c...

Biomorphic Multi-Agent Architecture for Persistent Computing

Science.gov (United States)

Lodding, Kenneth N.; Brewster, Paul

2009-01-01

A multi-agent software/hardware architecture, inspired by the multicellular nature of living organisms, has been proposed as the basis of design of a robust, reliable, persistent computing system. Just as a multicellular organism can adapt to changing environmental conditions and can survive despite the failure of individual cells, a multi-agent computing system, as envisioned, could adapt to changing hardware, software, and environmental conditions. In particular, the computing system could continue to function (perhaps at a reduced but still reasonable level of performance) if one or more component( s) of the system were to fail. One of the defining characteristics of a multicellular organism is unity of purpose. In biology, the purpose is survival of the organism. The purpose of the proposed multi-agent architecture is to provide a persistent computing environment in harsh conditions in which repair is difficult or impossible. A multi-agent, organism-like computing system would be a single entity built from agents or cells. Each agent or cell would be a discrete hardware processing unit that would include a data processor with local memory, an internal clock, and a suite of communication equipment capable of both local line-of-sight communications and global broadcast communications. Some cells, denoted specialist cells, could contain such additional hardware as sensors and emitters. Each cell would be independent in the sense that there would be no global clock, no global (shared) memory, no pre-assigned cell identifiers, no pre-defined network topology, and no centralized brain or control structure. Like each cell in a living organism, each agent or cell of the computing system would contain a full description of the system encoded as genes, but in this case, the genes would be components of a software genome.

Agent-based simulation of animal behaviour

NARCIS (Netherlands)

C.M. Jonker (Catholijn); J. Treur

1998-01-01

textabstract In this paper it is shown how animal behaviour can be simulated in an agent-based manner. Different models are shown for different types of behaviour, varying from purely reactive behaviour to pro-active, social and adaptive behaviour. The compositional development method for

Trade-offs in osmoregulation and parallel shifts in molecular function follow ecological transitions to freshwater in the Alewife

Science.gov (United States)

Velotta, Jonathan P.; McCormick, Stephen; Schultz, Eric T.

2015-01-01

Adaptation to freshwater may be expected to reduce performance in seawater because these environments represent opposing selective regimes. We tested for such a trade-off in populations of the Alewife (Alosa pseudoharengus). Alewives are ancestrally anadromous, and multiple populations have been independently restricted to freshwater (landlocked). We conducted salinity challenge experiments, whereby juvenile Alewives from one anadromous and multiple landlocked populations were exposed to freshwater and seawater on acute and acclimation timescales. In response to acute salinity challenge trials, independently derived landlocked populations varied in the degree to which seawater tolerance has been lost. In laboratory-acclimation experiments, landlocked Alewives exhibited improved freshwater tolerance, which was correlated with reductions in seawater tolerance and hypo-osmotic balance, suggesting that trade-offs in osmoregulation may be associated with local adaptation to freshwater. We detected differentiation between life-history forms in the expression of an ion-uptake gene (NHE3), and in gill Na+/K+-ATPase activity. Trade-offs in osmoregulation, therefore, may be mediated by differentiation in ion-uptake and salt-secreting pathways.

FRESH FISH TRADE NETWORKS IN THE STREET MARKETS OF PALMAS, TOCANTINS STATE, BRAZIL

Directory of Open Access Journals (Sweden)

Kelly Bessa

2016-12-01

Full Text Available This paper focuses on fresh fish trade networks found in the street markets of Palmas, capital of Tocantins state, Brazil, so as to identify the economic agents involved and the various geographical spaces which interact as a result of these networks. Fresh fish trade in Palmas takes place in distributor warehouses, grocery stores, supermarkets and hypermarkets, fish shops, and fishing communities, but it is street markets that constitute the most popular sale venues. Market sellers establish upstream supply networks with sectors in the fish food system (suppliers in primary and secondary production, distribution, and retail, whose interactions generate connections in Palmas (fishermen, distributors, retailers on a local scale, as well as connections with locations in Tocantins and Pará states (fishermen, fisheries, cold storage companies on a regional scale. Sellers also establish downstream trade networks with the end consumer at markets and with establishments in the food and small retail sectors, whose interactions produce mostly local connections, in Palmas and in the Luzimangues district (close to Palmas. Such connections are marked by consumption processes in these urban areas. Key-words: network, fresh fish trade, street markets.

The Dynamics of Learning and the Emergence of Distributed Adaption

National Research Council Canada - National Science Library

Crutchfield, James P

2006-01-01

.... The second goal was to adapt this single-agent learning theory and associated learning algorithms to the distributed setting in which a population of autonomous agents communicate to achieve a desired group task...

Implications of the New Regional Trade Agreements for the World Trading System

Directory of Open Access Journals (Sweden)

Agnes Ghibuțiu

2017-04-01

Full Text Available The year 2013 witnessed an outstanding rise in the pace and scale of negotiations on regional trade agreements (RTAs. While RTAs are not a new phenomenon, current negotiations involve multiple parties and/or major trading countries that have a significant combined economic weight, i.e. mega-RTAs. This paper looks at the recent surge in trade regionalism and addresses some of the key issues related to the potential impact of mega-RTAs upon the world trading system and global trade patterns. It examines the peculiarities of the new mega-RTAs and the factors underlying their proliferation, and discusses the main concerns raised by their foreseeable impact on excluded countries and the wider trading system. The paper finds that, if successfully concluded, mega-RTAs are likely to have far-reaching implications for the world trading regime, affecting its transparency and coherence. Nevertheless, the adverse effects could be cushioned through a revival of trading nations’ interest in the multilateral Doha Round talks.

Multi-level policies and adaptive social networks – a conceptual modeling study for maintaining a polycentric governance system

Directory of Open Access Journals (Sweden)

Jean-Denis Mathias

2017-03-01

Full Text Available Information and collaboration patterns embedded in social networks play key roles in multilevel and polycentric modes of governance. However, modeling the dynamics of such social networks in multilevel settings has been seldom addressed in the literature. Here we use an adaptive social network model to elaborate the interplay between a central and a local government in order to maintain a polycentric governance. More specifically, our analysis explores in what ways specific policy choices made by a central agent affect the features of an emerging social network composed of local organizations and local users. Using two types of stylized policies, adaptive co-management and adaptive one-level management, we focus on the benefits of multi-level adaptive cooperation for network management. Our analysis uses viability theory to explore and to quantify the ability of these policies to achieve specific network properties. Viability theory gives the family of policies that enables maintaining the polycentric governance unlike optimal control that gives a unique blueprint. We found that the viability of the policies can change dramatically depending on the goals and features of the social network. For some social networks, we also found a very large difference between the viability of the adaptive one-level management and adaptive co-management policies. However, results also show that adaptive co-management doesn’t always provide benefits. Hence, we argue that applying viability theory to governance networks can help policy design by analyzing the trade-off between the costs of adaptive co-management and the benefits associated with its ability to maintain desirable social network properties in a polycentric governance framework.

Trade Integration and Trade Imbalances in the European Union: A Network Perspective

Science.gov (United States)

Krings, Gautier M.; Carpantier, Jean-François; Delvenne, Jean-Charles

2014-01-01

We study the ever more integrated and ever more unbalanced trade relationships between European countries. To better capture the complexity of economic networks, we propose two global measures that assess the trade integration and the trade imbalances of the European countries. These measures are the network (or indirect) counterparts to traditional (or direct) measures such as the trade-to-GDP (Gross Domestic Product) and trade deficit-to-GDP ratios. Our indirect tools account for the European inter-country trade structure and follow (i) a decomposition of the global trade flow into elementary flows that highlight the long-range dependencies between exporting and importing economies and (ii) the commute-time distance for trade integration, which measures the impact of a perturbation in the economy of a country on another country, possibly through intermediate partners by domino effect. Our application addresses the impact of the launch of the Euro. We find that the indirect imbalance measures better identify the countries ultimately bearing deficits and surpluses, by neutralizing the impact of trade transit countries, such as the Netherlands. Among others, we find that ultimate surpluses of Germany are quite concentrated in only three partners. We also show that for some countries, the direct and indirect measures of trade integration diverge, thereby revealing that these countries (e.g. Greece and Portugal) trade to a smaller extent with countries considered as central in the European Union network. PMID:24465381

Trade integration and trade imbalances in the European Union: a network perspective.

Science.gov (United States)

Krings, Gautier M; Carpantier, Jean-François; Delvenne, Jean-Charles

2014-01-01

We study the ever more integrated and ever more unbalanced trade relationships between European countries. To better capture the complexity of economic networks, we propose two global measures that assess the trade integration and the trade imbalances of the European countries. These measures are the network (or indirect) counterparts to traditional (or direct) measures such as the trade-to-GDP (Gross Domestic Product) and trade deficit-to-GDP ratios. Our indirect tools account for the European inter-country trade structure and follow (i) a decomposition of the global trade flow into elementary flows that highlight the long-range dependencies between exporting and importing economies and (ii) the commute-time distance for trade integration, which measures the impact of a perturbation in the economy of a country on another country, possibly through intermediate partners by domino effect. Our application addresses the impact of the launch of the Euro. We find that the indirect imbalance measures better identify the countries ultimately bearing deficits and surpluses, by neutralizing the impact of trade transit countries, such as the Netherlands. Among others, we find that ultimate surpluses of Germany are quite concentrated in only three partners. We also show that for some countries, the direct and indirect measures of trade integration diverge, thereby revealing that these countries (e.g. Greece and Portugal) trade to a smaller extent with countries considered as central in the European Union network.

Energy trading

International Nuclear Information System (INIS)

Beckmann, K.; Schroeter, S.

2009-01-01

Two brief articles and two interviews deal with the subject of energy trading. Power and gas exchanges in Europe multiply, but, experts say, we are nowhere near a mature, integrated European energy market as yet. Trading regulations need to be improved and harmonised and interconnections expanded. European Energy Review assesses the state of energy trading in Europe and interviews the ceo's of NordPool (the Nordic power exchange) and APX (Amsterdam Power Exchange)

The value of less connected agents in Boolean networks

Science.gov (United States)

Epstein, Daniel; Bazzan, Ana L. C.

2013-11-01

In multiagent systems, agents often face binary decisions where one seeks to take either the minority or the majority side. Examples are minority and congestion games in general, i.e., situations that require coordination among the agents in order to depict efficient decisions. In minority games such as the El Farol Bar Problem, previous works have shown that agents may reach appropriate levels of coordination, mostly by looking at the history of past decisions. Not many works consider any kind of structure of the social network, i.e., how agents are connected. Moreover, when structure is indeed considered, it assumes some kind of random network with a given, fixed connectivity degree. The present paper departs from the conventional approach in some ways. First, it considers more realistic network topologies, based on preferential attachments. This is especially useful in social networks. Second, the formalism of random Boolean networks is used to help agents to make decisions given their attachments (for example acquaintances). This is coupled with a reinforcement learning mechanism that allows agents to select strategies that are locally and globally efficient. Third, we use agent-based modeling and simulation, a microscopic approach, which allows us to draw conclusions about individuals and/or classes of individuals. Finally, for the sake of illustration we use two different scenarios, namely the El Farol Bar Problem and a binary route choice scenario. With this approach we target systems that adapt dynamically to changes in the environment, including other adaptive decision-makers. Our results using preferential attachments and random Boolean networks are threefold. First we show that an efficient equilibrium can be achieved, provided agents do experimentation. Second, microscopic analysis show that influential agents tend to consider few inputs in their Boolean functions. Third, we have also conducted measurements related to network clustering and centrality

NEUMANNIAN ECONOMY IN MULTI-AGENT APPROACH. INVESTIGATION OF STABILITY AND INSTABILITY IN ECONOMIC GROWTH

Directory of Open Access Journals (Sweden)

Katalin Martinas

2004-06-01

Full Text Available Axiomatic foundation of non-equilibrium microeconomics is outlined. The economic activity is modelled as transformation and transport of commodities (materials owned by the agents. Rate of transformations (production intensity, and the rate of transport (trade are defined by the agents. Economic decision rules are derived from the observed economic behaviour. The non-linear equations are solved numerically for the Neumannian economy. The emergence of the equilibrium market structure appears as an order out of chaos process.

76 FR 71378 - Labor Advisory Committee for Trade Negotiations and Trade Policy

Science.gov (United States)

2011-11-17

... DEPARTMENT OF LABOR Office of the Secretary Labor Advisory Committee for Trade Negotiations and Trade Policy ACTION: Meeting notice. SUMMARY: Pursuant to the provisions of the Federal Advisory... Committee for Trade Negotiation and Trade Policy. Date, Time, Place: November 30, 2011; 2-4:30 p.m.; U.S...

77 FR 65581 - Labor Advisory Committee for Trade Negotiations and Trade Policy

Science.gov (United States)

2012-10-29

... DEPARTMENT OF LABOR Office of the Secretary Labor Advisory Committee for Trade Negotiations and Trade Policy ACTION: Meeting notice. SUMMARY: Pursuant to the provisions of the Federal Advisory... Committee for Trade Negotiation and Trade Policy. Date, Time, Place: November 13, 2012; 10:00 a.m.-12:00 p.m...

BENEFITS AND DRAWBACKS OF ONLINE TRADING VERSUS TRADITIONAL TRADING. EDUCATIONAL FACTORS IN ONLINE TRADING

Directory of Open Access Journals (Sweden)

Petric (Iancu Ioana Ancuta

2015-07-01

Full Text Available In terms of marketing, online trading is a new distribution channel and trading platforms are products of Investment and Financial Services Companies. Internet shortens the connection between the investor and the products they wish to purchase (shares, futures, CFDs, government securities, bonds, etc., and in some cases it no longer needs a security broker. Increasing use of the Internet and increasing competitiveness between Investment and Financial Services Companies do the latter, to seek new distribution channels to specific products. The purpose of this paper is to examine to what extent the investor education level affects the decision to move from traditional trading to online trading and the benefits and disadvantages of these types of transactions. To whom should the Investment and Financial Services Companies guide their marketing campaign to attract more investors for online platforms? The work presented is part of a larger project that will be part of author thesis, studying other factors that influence the decision to move from traditional to online trading: cost factor, time factor, psychological and social attributes of investors, yield portfolios and technological capacities of Investment and Financial Services Companies. Starting from the idea that with the increase of experience in stock investments the investors will want to make their own decisions, Investment and Financial Services Companies should provide new products. Compared to competitors, an Investment and Financial Services Company must innovate, and information technology currently offers the tools for innovation facilities. At the same time, the existence and development of the Internet has made the transaction without assistance or with minimal human intervention possible (Voss, 2000. The difference is in the knowledge about stock market, the speed the transaction orders arrive in the stock market, direct access to multiple markets, transaction costs and the level

Adaptive evolution of defense ability leads to diversification of prey species.

Science.gov (United States)

Zu, Jian; Wang, Jinliang; Du, Jianqiang

2014-06-01

In this paper, by using the adaptive dynamics approach, we investigate how the adaptive evolution of defense ability promotes the diversity of prey species in an initial one-prey-two-predator community. We assume that the prey species can evolve to a safer strategy such that it can reduce the predation risk, but a prey with a high defense ability for one predator may have a low defense ability for the other and vice versa. First, by using the method of critical function analysis, we find that if the trade-off is convex in the vicinity of the evolutionarily singular strategy, then this singular strategy is a continuously stable strategy. However, if the trade-off is weakly concave near the singular strategy and the competition between the two predators is relatively weak, then the singular strategy may be an evolutionary branching point. Second, we find that after the branching has occurred in the prey strategy, if the trade-off curve is globally concave, then the prey species might eventually evolve into two specialists, each caught by only one predator species. However, if the trade-off curve is convex-concave-convex, the prey species might eventually branch into two partial specialists, each being caught by both of the two predators and they can stably coexist on the much longer evolutionary timescale.

Climate, energy and emissions trading in the EU and DK

International Nuclear Information System (INIS)

Dyck-Madsen, S.

2004-04-01

European Union member states are facing two serious challenges: human-induced climatic changes and oil shortage. Evidence that human-induced global heating is threatening the climatic balance is piling up and the conflicts over the last oil resources are becoming critical. The European Union has neither large oil resources nor foreign-political or military power to conquer additional oil resources. The EU Commission's awareness of these facts is influencing the EU energy and climate policy. Recently EU launched the directive on carbon dioxide emissions trading within certain energy-heavy sectors. The greenhouse gas emission allowance trading directive requires a national ceiling on the allocation of CO 2 quotas for the heavy industry and energy sectors, thus adapting the quantity of quotas to the Kyoto requirements. This requirement can be quite extensive for the sectors affected by the greenhouse gas emission allowance trading directive, if national governments choose to abstain from political intervention in order to reduce release of greenhouse gases in sectors outside the emissions trading, e.g. agriculture, transportation, households, and smaller industry and service. Lack of action in these sectors will require the governments to impose either large burdens or use of national Joint Implementation and Clean Development agreements on the heavy industry and energy sectors outside national borders, thus conflicting with the Kyoto Protocol. (BA)

A Comparative Analysis of Trade Facilitation in Selected Regional and Bilateral Trade Agreement

OpenAIRE

Institute for International Trade

2006-01-01

This study compared the treatment of trade facilitation in four selected regional trade agreements, AFTA, APEC, SAFRA and PACER, and in one bilateral free trade agreement being the Australia-Singapore Free Trade Agreement (ASFTA), with a view to determining model trade facilitation principles and measures which may be instructive for developing country negotiations and policy makers.

REGIONALIZATION AND INTRA-INDUSTRY TRADE. AN ANALYSIS OF AUTOMOBILE INDUSTRY TRADE IN NAFTA

OpenAIRE

Sylvie MONTOUT; Jean-Louis MUCCHIELLI; Soledad ZIGNAGO

2002-01-01

As was shown in some previous studies, the creation of the North American Free Trade American (NAFTA) has significantly increased trade and investment flows between member countries. Consequently, it seems appropriate to analyze the incidences of the free trade agreement on the nature of trade. In this paper, we study the intra-industry trade in the automobile industry within the NAFTA area. Our results highlight an increase in intra-industry trade since the beginning of the 1990s. The import...

Understanding the limit order book: Conditioning on trade informativeness

OpenAIRE

Beltran, Héléna; Grammig, Joachim; Menkveld, Albert J.

2005-01-01

Electronic limit order books are ubiquitous in markets today. However, theoretical models for limit order markets fail to explain the real world data well. Sandas (2001) tests the classic Glosten (1994) model for order book equilibrium and rejects it. We reconfirm this result for one of the largest European stock markets. We then relax one of the model's assumptions and allow the informational content of trades to change over time. Adapting Hasbrouck's (1991a,b) methodology to estimate time v...

Tissue-based standoff biosensors for detecting chemical warfare agents

Science.gov (United States)

Greenbaum, Elias; Sanders, Charlene A.

2003-11-18

A tissue-based, deployable, standoff air quality sensor for detecting the presence of at least one chemical or biological warfare agent, includes: a cell containing entrapped photosynthetic tissue, the cell adapted for analyzing photosynthetic activity of the entrapped photosynthetic tissue; means for introducing an air sample into the cell and contacting the air sample with the entrapped photosynthetic tissue; a fluorometer in operable relationship with the cell for measuring photosynthetic activity of the entrapped photosynthetic tissue; and transmitting means for transmitting analytical data generated by the fluorometer relating to the presence of at least one chemical or biological warfare agent in the air sample, the sensor adapted for deployment into a selected area.

Greenhouse gas trading

Energy Technology Data Exchange (ETDEWEB)

Drazilov, P. [Natsource-Tullett Emissions Brokerage, Toronto, ON (Canada)

2001-07-01

Natsource-Tullett Emissions Brokerage is a market leader in natural gas, electricity, coal, and weather, emissions with a total of more than $2 billion by volume in emissions transactions in the United States, Canada, Australia, Japan, and Europe. This power point presentation addressed issues dealing with global warming, the Kyoto Protocol, and explained where we are in terms of reaching commitments for the first compliance period between 2008-2012. The paper focused on international emissions trading (IET), joint implementation (JI) and the clean development mechanism (CDM) and explained how greenhouse gases are traded. Emissions trading refers to the trade of carbon dioxide, methane, nitrous oxides, perfluoro-carbons, hydrofluorocarbons, and sulphur hexafluorides. The motivational drivers for trading were outlined in terms of liability for buyers and assets for sellers. To date, trading activity is nearly 120 transactions with nearly 70 million tons of carbon dioxide equivalent. tabs., figs.

Reconfiguring trade mark law

DEFF Research Database (Denmark)

Elsmore, Matthew James

2013-01-01

-border setting, with a particular focus on small business and consumers. The article's overall message is to call for a rethink of received wisdom suggesting that trade marks are effective trade-enabling devices. The case is made for reassessing how we think about European trade mark law.......First, this article argues that trade mark law should be approached in a supplementary way, called reconfiguration. Second, the article investigates such a reconfiguration of trade mark law by exploring the interplay of trade marks and service transactions in the Single Market, in the cross...

INDONESIAN TRADE UNDER CHINA FREE TRADE AREA

Directory of Open Access Journals (Sweden)

Tavi Supriana

2011-09-01

Full Text Available This paper investigates the implementation of CAFTA (China-Asean Free Trade Area on the international trade flows across Indonesia, China and the rest of ASEAN using a gravitation model. It finds the evidence that the influence of diversion and creation effects on China are significant, while the influence of both effects on Indonesia are not significant. It also finds that the diversion effect, which leads to a decrease in society’s wealth, is greater than that of the creation effect. As a consequence, the gap across countries involved in the trade agreement is wider. Keywords: CAFTA, gravitation model, diversion effect, creation effectJEL classification numbers: F13, F14, F15

Regional Monopoly and Interregional and Intraregional Competition: The Parallel Trade in Coca-Cola between Shanghai and Hangzhou in China

OpenAIRE

Yeung, Godfrey; Mok, Vincent

2006-01-01

This article uses a “principal-agent-subagent” analytical framework and data that were collected from field surveys in China to (1) investigate the nature and causes of the parallel trade in Coca-Cola between Shanghai and Hangzhou and (2) assess the geographic and theoretical implications for the regional monopolies that have been artificially created by Coca-Cola in China. The parallel trade in Coca-Cola is sustained by its intraregional rivalry with Pepsi-Cola in Shanghai, where Coca-Cola (...

Trade, Labor, Legitimacy

OpenAIRE

Guzman, Andrew

2003-01-01

The relationship between international trade and labor standards is one of several controversial issues facing the WTO. Proponents of a trade-labor link argue that labor is a human rights issue and that trade sanctions represent a critical tool in the effort to improve international working conditions. Opponents argue that a link between trade and labor would open the door to protectionist measures that would target low wage countries and harm the very workers the policy is intended to help. ...

Organophosphate Nerve Agent Detection with Europium Complexes

Directory of Open Access Journals (Sweden)

Jake R. Schwierking

2004-01-01

Full Text Available We explore the detection of paraoxon, a model compound for nonvolatile organophosphate nerve agents such as VX. The detection utilizes europium complexes with 1,10 phenanthroline and thenoyltrifluoroacetone as sensitizing ligands. Both europium luminescence quenching and luminescence enhancement modalities are involved in the detection, which is simple, rapid, and sensitive. It is adaptable as well to the more volatile fluorophosphate nerve agents. It involves nothing more than visual luminescence observation under sample illumination by an ordinary hand-held ultraviolet lamp.

The Algerian Foreign Trade between the Multilateral Trading System and the Regionalism

Directory of Open Access Journals (Sweden)

Khayreddine Belaaze

2014-04-01

Full Text Available This contribution aims at highlighting a major challenge facing global trade and trade in developing countries. Indeed, regional and preferential trade agreements are now more than ever inconsistent and incoherent and one of the principles of the World Trade Organization, the clause of the most favored nation requiring eliminated all forms of discrimination between trading parties, but what we see in regional trade agreements that the preferential tariffs based on a principle of discrimination. All regional trade agreements granting preferential tariffs between member countries, these preferences do not include the remains of non-member countries (rest of world. On the other hand, preferential tariffs are lower than MFN rates. Meanwhile, the number of regional agreements has doubled since 1995 date creation of the WTO, and Algeria like other developing countries considered one of countries which have not benefit a lot from this situation.

Greenhouse gas credits trade versus biomass trade – weighing (Workshop Summary)

NARCIS (Netherlands)

Junginger, H.M.; Faaij, A.P.C.; Robertson, K.; Woes-Gallasch, S.; Schlamadinger, B.

2006-01-01

A workshop entitled ‘Greenhouse gas credits trade versus biomass trade – weighing the benefits’, jointly organised by IEA Bioenergy Tasks 38 (GHG Balances of Biomass and Bioenergy Systems) and 40 (Sustainable International Bioenergy Trade: Securing Supply and Demand), and ENOVA, took place in

Adaptive Home System Using Wireless Sensor Network And Multi Agent System

OpenAIRE

Jayarani Kamble; Prof.Nandini Dhole

2014-01-01

Smart Home is an emerging technology growing continuously which includes number of new technologies which helps to improve human’s quality of living. This paper proposes an adaptive home system for optimum utilization of power, through Artificial Intelligence and Wireless Sensor network. Artificial Intelligence is a technology for developing adaptive system that can perceive the enviornmrnt, learn from the environment and can make decision using Rule based system.Zigbee is a w...

International emissions trading

DEFF Research Database (Denmark)

Boom, Jan Tjeerd

This thesis discusses the design and political acceptability of international emissions trading. It is shown that there are several designs options for emissions trading at the national level that have a different impact on output and thereby related factors such as employment and consumer prices....... The differences in impact of the design make that governments may prefer different designs of emissions trading in different situations. The thesis furthermore establishes that international emissions trading may lead to higher overall emissions, which may make it a less attractive instrument....

Modeling agents with a theory of mind : Theory-theory versus simulation theory

NARCIS (Netherlands)

Harbers, M.; Bosch, K. van den; Meyer, J.J.C.

2012-01-01

Virtual training systems with intelligent agents provide an effective means to train people for complex, dynamic tasks like crisis management or firefighting. For successful training, intelligent virtual agents should be able to show believable behavior, adapt their behavior to the trainee’s

Banking and Trading

NARCIS (Netherlands)

Boot, A.W.A.; Ratnovski, L.

2016-01-01

We study the interaction between relationship banking and short-term arm’s length activities of banks, called trading. We show that a bank can use the franchise value of its relationships to expand the scale of trading, but may allocate too much capital to trading ex post , compromising its ability

Trade reform in Iran for accession to the World Trade Organization

NARCIS (Netherlands)

Farajzadeh, Zakariya; Zhu, Xueqin; Bakhshoodeh, Mohammad

2017-01-01

We developed a computable general equilibrium (CGE) model to study the potential welfare and environmental impacts of Iran's trade reform for accession to the World Trade Organization (WTO). Our results show that removing trade barriers not only results in higher welfare and GDP as well as lower

Application of Complex Adaptive Systems in Portfolio Management

Science.gov (United States)

Su, Zheyuan

2017-01-01

Simulation-based methods are becoming a promising research tool in financial markets. A general Complex Adaptive System can be tailored to different application scenarios. Based on the current research, we built two models that would benefit portfolio management by utilizing Complex Adaptive Systems (CAS) in Agent-based Modeling (ABM) approach.…

Benefits of trade facilitation as a simpler procedure for world trade growth

OpenAIRE

Miteva-Kacarski, Emilija; Gorgieva-Trajkovska, Olivera

2011-01-01

“The simplification and harmonisation of international trade procedures” where trade procedures are the “activities, practices and formalities involved in collecting, presenting, communicating and processing data required for the movement of goods in international trade” is trade facilitation according the WTO. Trade facilitation initiatives benefit both the business community and governments. The business community benefits by obtaining enhanced competitiveness in national and international ...

World Trade Organisation (WTO): Trade rules/agreements and ...

African Journals Online (AJOL)

The GATT (General Agreement on Trade and Tariffs) rules of 1947 were seen as prejudicial to the economic and development concerns of developing countries. With the coming into effect of World Trade Organization (WTO), it was expected that some of the concerns of the developing countries will be addressed.

48 CFR 52.225-3 - Buy American Act-Free Trade Agreements-Israeli Trade Act.

Science.gov (United States)

2010-10-01

... Trade Agreements-Israeli Trade Act. 52.225-3 Section 52.225-3 Federal Acquisition Regulations System... Text of Provisions and Clauses 52.225-3 Buy American Act—Free Trade Agreements—Israeli Trade Act. As prescribed in 25.1101(b)(1)(i), insert the following clause: Buy American Act—Free Trade Agreements—Israeli...

The Carbon Trading Price and Trading Volume Forecast in Shanghai City by BP Neural Network

OpenAIRE

Liu Zhiyuan; Sun Zongdi

2017-01-01

In this paper, the BP neural network model is established to predict the carbon trading price and carbon trading volume in Shanghai City. First of all, we find the data of carbon trading price and carbon trading volume in Shanghai City from September 30, 2015 to December 23, 2016. The carbon trading price and trading volume data were processed to get the average value of each 5, 10, 20, 30, and 60 carbon trading price and trading volume. Then, these data are used as input of BP neural network...

Nutrition labelling is a trade policy issue: lessons from an analysis of specific trade concerns at the World Trade Organization.

Science.gov (United States)

Thow, Anne Marie; Jones, Alexandra; Hawkes, Corinna; Ali, Iqra; Labonté, Ronald

2017-01-12

Interpretive nutrition labels provide simplified nutrient-specific text and/or symbols on the front of pre-packaged foods, to encourage and enable consumers to make healthier choices. This type of labelling has been proposed as part of a comprehensive policy response to the global epidemic of non-communicable diseases. However, regulation of nutrition labelling falls under the remit of not just the health sector but also trade. Specific Trade Concerns have been raised at the World Trade Organization's Technical Barriers to Trade Committee regarding interpretive nutrition labelling initiatives in Thailand, Chile, Indonesia, Peru and Ecuador. This paper presents an analysis of the discussions of these concerns. Although nutrition labelling was identified as a legitimate policy objective, queries were raised regarding the justification of the specific labelling measures proposed, and the scientific evidence for effectiveness of such measures. Concerns were also raised regarding the consistency of the measures with international standards. Drawing on policy learning theory, we identified four lessons for public health policy makers, including: strategic framing of nutrition labelling policy objectives; pro-active policy engagement between trade and health to identify potential trade issues; identifying ways to minimize potential 'practical' trade concerns; and engagement with the Codex Alimentarius Commission to develop international guidance on interpretative labelling. This analysis indicates that while there is potential for trade sector concerns to stifle innovation in nutrition labelling policy, care in how interpretive nutrition labelling measures are crafted in light of trade commitments can minimize such a risk and help ensure that trade policy is coherent with nutrition action. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Trade Blocs, Currency Blocs and the Disintegration of World Trade in the 1930s

OpenAIRE

Eichengreen, Barry; Irwin, Douglas

1993-01-01

The dramatic implosion and regionalization of international trade during the 1930s has often been blamed on the trade and foreign exchange policies that emerged in the interwar period. We provide new evidence on the impact of trade and currency blocs on trade flows from 1928 1938 that suggests a blanket indictment of interwar trade policies and payments arrangements is not warranted. Discriminatory trade policies and international monetary arrangements had neither a uniformly favorable nor un...

Are Preferential Trade Agreements with Non-trade Objectives a Stumbling Block for Multilateral Liberalization?

OpenAIRE

Nuno Limão

2007-01-01

In many preferential trade agreements (PTAs), countries exchange not only reductions in trade barriers but also cooperation in non-trade issues such as labour and environmental standards, intellectual property, etc. We provide a model of PTAs motivated by cooperation in non-trade issues and analyse its implications for global free trade and welfare. We find that such PTAs increase the cost of multilateral tariff reductions and thus cause a stumbling block to global free trade. This occurs bec...

Trade between China and the Netherlands: a case study of trade in tasks

NARCIS (Netherlands)

den Butter, F.A.G.; Hayat, R.

2013-01-01

Purpose - This paper argues that the recent rise in China Dutch trade is a typical example of two nations trading tasks rather than goods. Design/methodology/approach - China Dutch trade growth between 1996 and 2010 is compared with China’s trade growth with its main partners. In addition, the

To Trade or Not to Trade: Firm-Level Analysis of Emissions Trading in Santiago, Chile

International Nuclear Information System (INIS)

Coria, Jessica; Loefgren, Aasa; Sterner, Thomas

2009-01-01

Whether tradable permits are appropriate for use in transition and developing economies - given special social and cultural circumstances, such as the lack of institutions and lack of expertise with market-based policies - is much debated. We conducted interviews and surveyed a sample of firms subject to emissions trading programs in Santiago, Chile, one of the first cities outside the OECD that has implemented such trading. The information gathered allow us to study what factors affect the performance of the trading programs in practice and the challenges and advantages of applying tradable permits in less developed countries

Generative Agents for Player Decision Modeling in Games

DEFF Research Database (Denmark)

Holmgård, Christoffer; Liapis, Antonios; Togelius, Julian

2014-01-01

This paper presents a method for modeling player decision making through the use of agents as AI-driven personas. The paper argues that artificial agents, as generative player models, have properties that allow them to be used as psyhometrically valid, abstract simulations of a human player......’s internal decision making processes. Such agents can then be used to interpret human decision making, as personas and playtesting tools in the game design process, as baselines for adapting agents to mimic classes of human players, or as believable, human-like opponents. This argument is explored...... in a crowdsourced decision making experiment, in which the decisions of human players are recorded in a small-scale dungeon themed puzzle game. Human decisions are compared to the decisions of a number of a priori defined “archetypical” agent-personas, and the humans are characterized by their likeness...

I Feel You: The Design and Evaluation of a Domotic Affect-Sensitive Spoken Conversational Agent

Directory of Open Access Journals (Sweden)

Juan Manuel Montero

2013-08-01

Full Text Available We describe the work on infusion of emotion into a limited-task autonomous spoken conversational agent situated in the domestic environment, using a need-inspired task-independent emotion model (NEMO. In order to demonstrate the generation of affect through the use of the model, we describe the work of integrating it with a natural-language mixed-initiative HiFi-control spoken conversational agent (SCA. NEMO and the host system communicate externally, removing the need for the Dialog Manager to be modified, as is done in most existing dialog systems, in order to be adaptive. The first part of the paper concerns the integration between NEMO and the host agent. The second part summarizes the work on automatic affect prediction, namely, frustration and contentment, from dialog features, a non-conventional source, in the attempt of moving towards a more user-centric approach. The final part reports the evaluation results obtained from a user study, in which both versions of the agent (non-adaptive and emotionally-adaptive were compared. The results provide substantial evidences with respect to the benefits of adding emotion in a spoken conversational agent, especially in mitigating users’ frustrations and, ultimately, improving their satisfaction.

Monitoring presence of chemical agents

International Nuclear Information System (INIS)

Preston, J.M.

1984-01-01

The specification describes a case for use with a hand-portable chemical agent detector for continuously monitoring an atmosphere for the presence of predetermined chemical agents. The detector having means for ionizing air samples and providing at an output terminal electrical signals representative of the mobility spectrum of ionized chemical vapours produced by the ionizing means. The case comprises means for defining a chamber in the case for supporting and removably enclosing the detector, means for communicating ambient atmosphere to the chamber, electrical circuit means in the case, the circuit means being adapted to be detachably connected to the detector output terminal when the detector is positioned in the chamber and being responsive to the electrical signals for producing an alarm signal when the signals detect a chemical agent concentration in the atmosphere exceeding a predetermined concentration level, and alarm means responsive to the alarm signal. (author)

International Trade and Protectionism.

Science.gov (United States)

Stanford Univ., CA. Stanford Program on International and Cross Cultural Education.

This unit is designed to investigate the reasons for international trade and the issue of trade protectionism by focusing on the case study of the U.S. trade relationship with Taiwan. The unit begins with a simulation that highlights the concepts of global interdependence, the need for international trade, and the distribution of the world's…

Racial Trade Barriers?

DEFF Research Database (Denmark)

Bjerre, Jacob Halvas

. This paper analyzes the racial policies pursued in the foreign trade and argues that we need to recognize Aryanization as a world-wide policy in order to fully understand its character and possible consequences. I focus on the pre-war period and analyze the case of Denmark from three different perspectives......: perpetrators, victims and bystanders. The analysis will show that race, economy and foreign trade were combined in an attempt to raise racial trade barriers. This forced the question of German racial policies on the Danish government, Danish-Jewish businesses, and German companies involved in foreign trade...

Emissions Trading

NARCIS (Netherlands)

Woerdman, Edwin; Backhaus, Juergen

2014-01-01

Emissions trading is a market-based instrument to achieve environmental targets in a cost-effective way by allowing legal entities to buy and sell emission rights. The current international dissemination and intended linking of emissions trading schemes underlines the growing relevance of this

Greenhouse gas emissions trading: Cogen case studies in the early trading market

International Nuclear Information System (INIS)

Buerer, Mary Jean

2001-01-01

An increasing number of companies are interested in opportunities to trade their reduction in greenhouse gas emissions from cogeneration on the emerging greenhouse gas emissions market. Only the UK and Denmark currently have emissions trading schemes, but they are under development in other European countries. Two frameworks currently exist for trading. Baseline-and-credit trading is used in Canada where companies can take part in two voluntary schemes (Greenhouse Gas Emission Reduction Trading Pilot or Clean Air Canada Inc). An example project from the CHP unit at DuPont's Maitland chemical production facility is given, with details of the baselines and calculations used. The other option is company-wide emissions trading. The example given here features the CHP units at BP's refinery and chemicals operations in Texas. The potential revenue from emission reduction projects could help to boost the economics of cogeneration projects

Impact of information cost and switching of trading strategies in an artificial stock market

Science.gov (United States)

Liu, Yi-Fang; Zhang, Wei; Xu, Chao; Vitting Andersen, Jørgen; Xu, Hai-Chuan

2014-08-01

This paper studies the switching of trading strategies and its effect on the market volatility in a continuous double auction market. We describe the behavior when some uninformed agents, who we call switchers, decide whether or not to pay for information before they trade. By paying for the information they behave as informed traders. First we verify that our model is able to reproduce some of the stylized facts in real financial markets. Next we consider the relationship between switching and the market volatility under different structures of investors. We find that there exists a positive relationship between the market volatility and the percentage of switchers. We therefore conclude that the switchers are a destabilizing factor in the market. However, for a given fixed percentage of switchers, the proportion of switchers that decide to buy information at a given moment of time is negatively related to the current market volatility. In other words, if more agents pay for information to know the fundamental value at some time, the market volatility will be lower. This is because the market price is closer to the fundamental value due to information diffusion between switchers.

A Multi-Agent Traffic Control Model Based on Distributed System

Directory of Open Access Journals (Sweden)

Qian WU

2014-06-01

Full Text Available With the development of urbanization construction, urban travel has become a quite thorny and imminent problem. Some previous researches on the large urban traffic systems easily change into NPC problems. We purpose a multi-agent inductive control model based on the distributed approach. To describe the real traffic scene, this model designs four different types of intelligent agents, i.e. we regard each lane, route, intersection and traffic region as different types of intelligent agents. Each agent can achieve the real-time traffic data from its neighbor agents, and decision-making agents establish real-time traffic signal plans through the communication between local agents and their neighbor agents. To evaluate the traffic system, this paper takes the average delay, the stopped time and the average speed as performance parameters. Finally, the distributed multi-agent is simulated on the VISSIM simulation platform, the simulation results show that the multi-agent system is more effective than the adaptive control system in solving the traffic congestion.

How fair is fair trade?

NARCIS (Netherlands)

Maseland, Robbert; Vaal, Albert de

2001-01-01

This paper investigates to what extent fair trade programmes, are indeed ‘fair’. This is accomplished by comparing fair trade with free trade and protectionist trade regimes on their compliance of the criteria set by the fair trade movement itself. This comparison is made using comparative cost

Agricultural Trade Barriers 10 years later Uruguay Round Trade Agreement Signature

OpenAIRE

Mahia, R.; Arce, Rafael de; Escribano, Gonzalo

2005-01-01

In this paper, an analysis of current state of agricultural trade barriers is carried out alter ten years of Uruguay Round Agricultural Trade Agreement Signature The descriptive analysis showed that small advances in trade barriers removing have been taken out. About the heterogeneity in tariff applications, tariff progresivity and peak tariffs, the same situation is pointed out.

Does AFTA Create More Trade for Thailand? An Investigation of Some Key Trade Indicators

Directory of Open Access Journals (Sweden)

Piriya Pholphirul

2010-04-01

Full Text Available This paper examines whether the ASEAN Free Trade Agreement (AFTA creates trade for Thailand or actually diverts it away from the country. It does this by analyzing various trade indicators: the Export Similarity Index, the Intra-Industry Trade Index, and Revealed Comparative Advantage (RCA rank correlation. By examining the patterns of trade between Thailand and other members of ASEAN, it reveals a high degree of similarity regarding the trade structure between Thailand and AFTA, which indicates that there will be fewer trade-creation benefits from AFTA and a greater likelihood of trade diversion once the AFTA scheme has been fully implemented. This similarity pattern explains the reasons for future collaboration among member countries and supportive arguments for the future extension of ASEAN ("ASEAN+". Market-penetration and development strategies should be employed by Thai exporters when accessing the ASEAN market.

An agent-based approach equipped with game theory. Strategic collaboration among learning agents during a dynamic market change in the California electricity crisis

Energy Technology Data Exchange (ETDEWEB)

Sueyoshi, Toshiyuki [Department of Management, New Mexico Institute of Mining and Technology, Socorro, NM 87801 (United States); Department of Industrial and Information Management, National Cheng Kung University, Tainan (China)

2010-09-15

An agent-based approach is a numerical (computer-intensive) method to explore the complex characteristics and dynamics of microeconomics. Using the agent-based approach, this study investigates the learning speed of traders and their strategic collaboration in a dynamic market change of electricity. An example of such a market change can be found in the California electricity crisis (2000-2001). This study incorporates the concept of partial reinforcement learning into trading agents and finds that they have two learning components: learning from a dynamic market change and learning from collaboration with other traders. The learning speed of traders becomes slow when a large fluctuation occurs in the power exchange market. The learning speed depends upon the type of traders, their learning capabilities and the fluctuation of market fundamentals. The degree of collaboration among traders gradually reduces during the electricity crisis. The strategic collaboration among traders is examined by a large simulator equipped with multiple learning capabilities. (author)

An agent-based approach equipped with game theory. Strategic collaboration among learning agents during a dynamic market change in the California electricity crisis

International Nuclear Information System (INIS)

Sueyoshi, Toshiyuki

2010-01-01

An agent-based approach is a numerical (computer-intensive) method to explore the complex characteristics and dynamics of microeconomics. Using the agent-based approach, this study investigates the learning speed of traders and their strategic collaboration in a dynamic market change of electricity. An example of such a market change can be found in the California electricity crisis (2000-2001). This study incorporates the concept of partial reinforcement learning into trading agents and finds that they have two learning components: learning from a dynamic market change and learning from collaboration with other traders. The learning speed of traders becomes slow when a large fluctuation occurs in the power exchange market. The learning speed depends upon the type of traders, their learning capabilities and the fluctuation of market fundamentals. The degree of collaboration among traders gradually reduces during the electricity crisis. The strategic collaboration among traders is examined by a large simulator equipped with multiple learning capabilities. (author)

Quantifying immediate price impact of trades based on the k-shell decomposition of stock trading networks

Science.gov (United States)

Xie, Wen-Jie; Li, Ming-Xia; Xu, Hai-Chuan; Chen, Wei; Zhou, Wei-Xing; Stanley, H. Eugene

2016-10-01

Traders in a stock market exchange stock shares and form a stock trading network. Trades at different positions of the stock trading network may contain different information. We construct stock trading networks based on the limit order book data and classify traders into k classes using the k-shell decomposition method. We investigate the influences of trading behaviors on the price impact by comparing a closed national market (A-shares) with an international market (B-shares), individuals and institutions, partially filled and filled trades, buyer-initiated and seller-initiated trades, and trades at different positions of a trading network. Institutional traders professionally use some trading strategies to reduce the price impact and individuals at the same positions in the trading network have a higher price impact than institutions. We also find that trades in the core have higher price impacts than those in the peripheral shell.

Protectionism, free trade and preferential trade: the Mexican experience 1970-2005

Directory of Open Access Journals (Sweden)

2007-03-01

Full Text Available This paper is a theoretical and applied analysis of free trade policies and protectionism. First, the evolution of free trade theories, vis-à-vis protectionist ideas, is described, starting from the classical economists, their assumptions and implications for attaining welfare Pareto optimality, full employment and growth. Secondly, a structural analysis of the Mexican economy’s performance in three successive but different periods, regarding trade policies for the last thirty-five years is presented. I conclude that extreme free-trade policies have not been good for economic stability, growth and employment creation in Mexico.

International trade and employment: trade partner country effects on jobs and wages

NARCIS (Netherlands)

Fortanier, F.N.; Jaarsma, M.; Korvorst, M.

2011-01-01

Recent academic research has consistently identified trading firms - both exporters and importers - to be larger, and to pay higher wages than their non-trading counterparts. However, not all trade is equal: imports from low-wage countries may destroy employment, particularly among low-skilled

40 CFR 90.206 - Trading.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Trading. 90.206 Section 90.206... Trading Provisions § 90.206 Trading. (a) An engine manufacturer may exchange emission credits with other engine manufacturers in trading, subject to the trading restriction specified in § 90.207(c)(2). (b...

International trade. Multinational aspects.

Science.gov (United States)

Ozawa, Y

2000-01-01

Of numerous regional economic agreements, the European Union (EU), the North American Free Trade Agreement (NAFTA), South American Common Market (MERCOSUR), the Association of Southeast Asian Nations (ASEAN), the South Asian Association for Regional Cooperation (SAARC) and the Australia-New Zealand Closer Economic Relations Agreement are examples that are actively pursuing regional integration for freer trade of animals and animal products. The World Trade Organization (WTO) believes that regional and multinational integration initiatives are complements rather than alternatives in the pursuit of more open trade. In the efforts to harmonize SPS standards among multilateral trading nations, it is recommended that national requirements meet the standards developed by the OIE and the FAO/WHO Codex Alimentarius Commission as the minimum requirements rather than adopting the standards of the lowest common denominator. Regional grouping may hinder multilateral or bilateral trade between the countries of a group and those of the other groups. How to eliminate such non-tariff barriers as traditional trade custom remains to be examined. Ongoing activities of VICH (Harmonisation of Technical Requirements for Registration of Veterinary Medical Products) may pave the way for more open trade in pharmaceutical products between multilateral regional groups.

The trade network in the dairy industry and its implication for the spread of contamination.

Science.gov (United States)

Pinior, B; Konschake, M; Platz, U; Thiele, H D; Petersen, B; Conraths, F J; Selhorst, T

2012-11-01

In case of an outbreak of a foodborne disease, administrative decisions in the context of crisis management are only efficient if they follow standard practices and are specifically adapted to the outbreak situation in a timely manner. These goals are hard to achieve. The complexity of national and global trade structures obscures a clear view of trade flows and, consequently, it is often impossible to unravel complex trade links quickly. Furthermore, increasing public concerns about possible health hazards caused by global trade put additional pressure on decision makers. The aim of this paper was to unveil the specific trade structures of the German milk supply chain, to highlight how these structures could affect the spatial spread of a hypothetical contaminant, and to quantify the risk of the contaminant reaching the consumer. To achieve this goal, the vertical and horizontal trade links between milk producers, dairies, and consumers were taken into account. The horizontal flow of milk between dairies (inter-dairy trade), which is intended to compensate a temporary over- or undersupply of milk, is of special importance in this respect. We hypothesized that the extent of inter-dairy trade would significantly influence the spatial spread of contaminated milk and the contamination risk. This hypothesis was tested using a computer simulation model that predicts the hypothetical spread of a contaminant via trade of milk. The model parameters were estimated using trade data collected in 2004 and 2010. The results of our study indicate that inter-dairy trade significantly influenced the contamination risk. Compared with a scenario with no inter-dairy trade, the risk that contaminated milk will reach the consumer was up to 4 times higher, even with moderate inter-dairy trade. The contamination risk depended on the extent of inter-dairy trade in a nonlinear way and reached its maximum asymptotically when inter-dairy trade increased. The contamination risk exhibited

Coping with scarcity: Fishing adaptability and culture in lake Chapala

Directory of Open Access Journals (Sweden)

Carmen Pedroza Gutiérrez

2017-11-01

Full Text Available This paper examines different adaptive responses that lakeside communities develop when faced with environmental change. The focus lies particularly on rural towns near lake Chapala, Mexico, affected by water level fluctuations. These situations require social reorganization, especially among groups whose survival is directly dependent on the lake’s integrity, such as fishermen.Using an adaptation and adaptability framework, various historical and current strategies used to confront scarcity and lake stress in La Palma, Michoacán are contrasted. Our aim is to highlight the changing social position of the fishing trade, and its most influential cultural features that have allowed its continuity.

Trade in health services.

Science.gov (United States)

Chanda, Rupa

2002-01-01

In light of the increasing globalization of the health sector, this article examines ways in which health services can be traded, using the mode-wise characterization of trade defined in the General Agreement on Trade in Services. The trade modes include cross- border delivery of health services via physical and electronic means, and cross-border movement of consumers, professionals, and capital. An examination of the positive and negative implications of trade in health services for equity, efficiency, quality, and access to health care indicates that health services trade has brought mixed benefits and that there is a clear role for policy measures to mitigate the adverse consequences and facilitate the gains. Some policy measures and priority areas for action are outlined, including steps to address the "brain drain"; increasing investment in the health sector and prioritizing this investment better; and promoting linkages between private and public health care services to ensure equity. Data collection, measures, and studies on health services trade all need to be improved, to assess better the magnitude and potential implications of this trade. In this context, the potential costs and benefits of trade in health services are shaped by the underlying structural conditions and existing regulatory, policy, and infrastructure in the health sector. Thus, appropriate policies and safeguard measures are required to take advantage of globalization in health services. PMID:11953795

Organ Trade

NARCIS (Netherlands)

J.A.E. Ambagtsheer (Frederike)

2017-01-01

markdownabstractOrgan trade constitutes the sale and purchase of organs for financial or material gain. Although prohibited since the 1980s, an increasing number of reports indicate its proliferation across the globe. Yet, many knowledge gaps exist on organ trade, in particular on the demand -and

Ecosystem service provision in a changing Europe: adapting to the impacts of combined climate and socio-economic change.

Science.gov (United States)

Dunford, Robert W; Smith, Alison C; Harrison, Paula A; Hanganu, Diana

Future patterns of European ecosystem services provision are likely to vary significantly as a result of climatic and socio-economic change and the implementation of adaptation strategies. However, there is little research in mapping future ecosystem services and no integrated assessment approach to map the combined impacts of these drivers. Map changing patterns in ecosystem services for different European futures and (a) identify the role of driving forces; (b) explore the potential influence of different adaptation options. The CLIMSAVE integrated assessment platform is used to map spatial patterns in services (food, water and timber provision, atmospheric regulation, biodiversity existence/bequest, landscape experience and land use diversity) for a number of combined climatic and socio-economic scenarios. Eight adaptation strategies are explored within each scenario. Future service provision (particularly water provision) will be significantly impacted by climate change. Socio-economic changes shift patterns of service provision: more dystopian societies focus on food provision at the expense of other services. Adaptation options offer significant opportunities, but may necessitate trade-offs between services, particularly between agriculture- and forestry-related services. Unavoidable trade-offs between regions (particularly South-North) are also identified in some scenarios. Coordinating adaptation across regions and sectors will be essential to ensure that all needs are met: a factor that will become increasingly pressing under dystopian futures where inter-regional cooperation breaks down. Integrated assessment enables exploration of interactions and trade-offs between ecosystem services, highlighting the importance of taking account of complex cross-sectoral interactions under different future scenarios of planning adaptation responses.

Revenue, welfare and trade effects of European Union Free Trade Agreement on South Africa

Directory of Open Access Journals (Sweden)

Kore M.A. Guei

2017-10-01

Full Text Available Background: Using the partial equilibrium WITS-SMART Simulation model to assess the impact of liberalisation under the Trade Development and Cooperation Agreement (TDCA of a free trade area between the European Union and South Africa. The identification of the impact of such agreement allows for trade policy negotiation adjustment that can be beneficial for South Africa. Aim: The aim of the study is to estimate and discuss the impact of a Free Trade Agreement (FTA with the European Union and South Africa. More specifically, the study intends to estimate the impact of revenue, welfare, imports, exports, trade creation and to come up with policies options for South Africa that can be used in negotiations and policy formulations. Setting: The study used international trade data (2012 available in the WITS-SMART model to assess bilateral trade agreement between the European Union and South Africa. Methods: To identify the impact on revenue, welfare, imports, exports and trade creation, the study simulated an FTA (0% tariff rate for all goods exchanged between the European Union and South Africa. Also, the elasticity of substitution used for the simulation model was 99%. Results: The findings of the study reveal that total trade effects in South Africa are likely to surge by US$ 1.036 billion with a total welfare valued at US$ 134 million. Dismantling tariffs on all European Union (EU goods would be beneficial to consumers through net trade creation. Total trade creation would be US$ 782 million. However, South African producers are likely to contribute a trade diversion of US$ 254 million which has a negative impact on consumer welfare. The country might also experience a revenue loss amounting to US$ 562 million because of the removal of tariffs. In trade, the country’s exports and imports to the EU are expected to increase by US$ 12.419 million and US$ 1.266 million, respectively. Conclusion: The European Union–South Africa FTA would

Preferential Trade Arrangements and the Pattern of Production and Trade when Inputs are Differentiated

NARCIS (Netherlands)

J.F. François (Joseph)

2005-01-01

textabstractThis paper is concerned with rules of origin when intermediate goods are differentiated. An analytical model emphasizes trade patterns and the relative importance of trade in intermediates given trade preferences. Econometric evidence based on intra-OECD trade in motor vehicles and motor

Managing the trade-public health linkage in defence of trade ...

African Journals Online (AJOL)

Managing the trade-public health linkage in defence of trade liberalisation and ... of United States-measures affecting the production and sale of clove cigarettes. ... Potchefstroom Electronic Law Journal/Potchefstroomse Elektroniese Regsblad.

Is the Classification of International Trade in Horizontal and Vertical Intra-Industry Trade Usable?

DEFF Research Database (Denmark)

Nielsen, Jørgen Ulff-Møller; Lüthje, Teit

2001-01-01

with vertical intra-industry trade (between Germany and France) making up 50-60%. The high level of vertical intra-industry trade probably covers up many products shifting between e.g. vertical and horizontal intra-industry. The statement from the literature that the European integration process involves heavy......Abstract On the basis of OECD trade statistics at SITC 5 digit level for the period 1961-1999 we show the classification of international trade in (a) inter-industry trade and (b) horizontal intra-industry and (c) vertical intra-industry trade used in the empirical trade literature to be non stable...... at the individual product level. This indicates that this type of statistical classification based on unit-values is probably not very useful. On the other hand, we also show in accordance with the literature that the aggregate distribution of trade into the three categories apparently is rather stable...

The future of coal trading. Part 1: obstacles to coal trading

International Nuclear Information System (INIS)

Schafer, W.; Vaninetti, J.

1998-01-01

'Trading' as used in this article means routine buying and selling of futures contracts or options and other derivatives of future contracts. The variable nature of coal, lack of liquidity, and the coal industry's understanding and acceptance of commodity trading concepts are identified as three major barriers to successful trading of a coal futures contract. The article discusses these obstacles

48 CFR 52.225-4 - Buy American Act-Free Trade Agreement-Israeli Trade Act Certificate.

Science.gov (United States)

2010-10-01

... Trade Agreement-Israeli Trade Act Certificate. 52.225-4 Section 52.225-4 Federal Acquisition Regulations... CLAUSES Text of Provisions and Clauses 52.225-4 Buy American Act—Free Trade Agreement—Israeli Trade Act... Agreement—Israeli Trade Act Certificate (JUN 2009) (a) The offeror certifies that each end product, except...

Analysis of Bullying in Cooperative Multi-agent Systems’ Communications

Directory of Open Access Journals (Sweden)

Celia Gutiérrez

2013-12-01

Full Text Available Cooperative Multi-agent Systems frameworks do not include modules to test communications yet. The proposed framework incorporates robust analysis tools using IDKAnalysis2.0 to evaluate bullying effect in communications. The present work is based on ICARO-T. This platform follows the Adaptive Multi-agent Systems paradigm. Experimentation with ICARO-T includes two deployments: the equitative and the authoritative. Results confirm the usefulness of the analysis tools when exporting to Cooperative Multi-agent Systems that use different configurations. Besides, ICARO-T is provided with new functionality by a set of tools for communication analysis.

International cooperation in the solution to trade-related invasive species risks.

Science.gov (United States)

Perrings, Charles; Burgiel, Stas; Lonsdale, Mark; Mooney, Harold; Williamson, Mark

2010-05-01

In this paper, we consider the factors behind the growth of invasive species as a global problem, and the scope for international cooperation and coordination in addressing that problem. This is limited by the terms of the various international agreements governing trade, health, and biodiversity. The default strategy in most cases has two parts: border protection and the control of or adaptation to introduced species that have escaped detection at the border. Most invasive species policy involves unilateral national defensive action as opposed to coordinated international action. We argue that an important part of the solution to the problem lies in global coordination and cooperation in the management of both pathways and sanitary and phytosanitary risks at all scales. More particularly, because invasive species are an externality of trade, transport, and travel that involve public goods, they require collective regulation of international markets that goes beyond that admitted under the World Trade Organization's (WTO) Agreement on the Application of Sanitary and Phytosanitary Measures. We argue that it is important to bring that agreement into conformity with the International Health Regulations (IHR), and to develop an international mechanism to generate and disseminate information on invasive species risks and their impacts.

Canadian municipal carbon trading primer

International Nuclear Information System (INIS)

Seskus, A.

2002-01-01

The trading of greenhouse gas (GHG) emissions is being suggested as an effective economic way to meet Canada's Kyoto target. Emissions trading is a market-based instrument that can help achieve environmental improvements while using the market to absorb the economical and effective measures to achieve emissions reductions. Placing a value on emissions means that in order to minimize costs, companies will be motivated to apply the lowest-cost emission reductions possible for regulatory approval. The two main types of emissions trading that exist in Canada are the trading of emissions that lead to the formation of smog or acid rain, and the trading of greenhouse gas emissions that lead to climate change. Since carbon dioxide is the most prevalent GHG, making up approximately 75 per cent of Canadian GHG emissions, the trading of units of GHGs is often referred to as carbon trading. The impact that emissions trading will have on municipal operations was the focus of this primer. The trading of GHG involves buying and selling of allowances of GHGs between contracting parties, usually between one party that is short of GHG credits and another that has excess credits. The 3 common approaches to emissions trading include allowance trading (cap and trade), credit trading (baseline and credit), and a hybrid system which combines both credit and allowance trading systems. The issues that impact municipalities include the debate regarding who owns the credits from landfills, particularly if power is generated using landfill gas and the power is sold as green power. Other viable questions were also addressed, including who can claim emission reduction credits if a city implements energy efficiency projects, or fuel substitution programs. Also, will municipalities be allowed to trade internationally, for example, with municipalities in the United States, and how should they spend their money earned from selling credits. This report also presents highlights from 3 emissions

77 FR 31393 - Labor Advisory Committee for Trade Negotiations and Trade Policy

Science.gov (United States)

2012-05-25

... DEPARTMENT OF LABOR Office of the Secretary Labor Advisory Committee for Trade Negotiations and Trade Policy ACTION: Notice of renewal. SUMMARY: Pursuant to the Federal Advisory Committee Act (FACA), as amended (5 U.S.C. App. 2), the Secretary of Labor and the United States Trade Representative have...

Judicial aspects of emission trade. Emission trade in the European Union

International Nuclear Information System (INIS)

Van Beuge, M.J.J.

2004-01-01

Emission trade will start in Europe in 2005. In a series of articles an overview will be given of several juridical aspects with respect to the international and national trade of emission. In part 1 attention was paid to the international judicial basis for the present climate policy. In this article an overview is given of developments with regard to emission trade in the European Union [nl

Functional Trade-Offs in Promiscuous Enzymes Cannot Be Explained by Intrinsic Mutational Robustness of the Native Activity.

Directory of Open Access Journals (Sweden)

Miriam Kaltenbach

2016-10-01

Full Text Available The extent to which an emerging new function trades off with the original function is a key characteristic of the dynamics of enzyme evolution. Various cases of laboratory evolution have unveiled a characteristic trend; a large increase in a new, promiscuous activity is often accompanied by only a mild reduction of the native, original activity. A model that associates weak trade-offs with "evolvability" was put forward, which proposed that enzymes possess mutational robustness in the native activity and plasticity in promiscuous activities. This would enable the acquisition of a new function without compromising the original one, reducing the benefit of early gene duplication and therefore the selection pressure thereon. Yet, to date, no experimental study has examined this hypothesis directly. Here, we investigate the causes of weak trade-offs by systematically characterizing adaptive mutations that occurred in two cases of evolutionary transitions in enzyme function: (1 from phosphotriesterase to arylesterase, and (2 from atrazine chlorohydrolase to melamine deaminase. Mutational analyses in various genetic backgrounds revealed that, in contrast to the prevailing model, the native activity is less robust to mutations than the promiscuous activity. For example, in phosphotriesterase, the deleterious effect of individual mutations on the native phosphotriesterase activity is much larger than their positive effect on the promiscuous arylesterase activity. Our observations suggest a revision of the established model: weak trade-offs are not caused by an intrinsic robustness of the native activity and plasticity of the promiscuous activity. We propose that upon strong adaptive pressure for the new activity without selection against the original one, selected mutations will lead to the largest possible increases in the new function, but whether and to what extent they decrease the old function is irrelevant, creating a bias towards initially weak

Adaptation to and Recovery from Global Catastrophe

Directory of Open Access Journals (Sweden)

Seth D. Baum

2013-03-01

Full Text Available Global catastrophes, such as nuclear war, pandemics and ecological collapse threaten the sustainability of human civilization. To date, most work on global catastrophes has focused on preventing the catastrophes, neglecting what happens to any catastrophe survivors. To address this gap in the literature, this paper discusses adaptation to and recovery from global catastrophe. The paper begins by discussing the importance of global catastrophe adaptation and recovery, noting that successful adaptation/recovery could have value on even astronomical scales. The paper then discusses how the adaptation/recovery could proceed and makes connections to several lines of research. Research on resilience theory is considered in detail and used to develop a new method for analyzing the environmental and social stressors that global catastrophe survivors would face. This method can help identify options for increasing survivor resilience and promoting successful adaptation and recovery. A key point is that survivors may exist in small isolated communities disconnected from global trade and, thus, must be able to survive and rebuild on their own. Understanding the conditions facing isolated survivors can help promote successful adaptation and recovery. That said, the processes of global catastrophe adaptation and recovery are highly complex and uncertain; further research would be of great value.

Trading volume and the number of trades : a comparative study using high frequency data

OpenAIRE

Izzeldin, Marwan

2007-01-01

Trading volume and the number of trades are both used as proxies for market activity, with disagreement as to which is the better proxy for market activity. This paper investigates this issue using high frequency data for Cisco and Intel in 1997. A number of econometric methods are used, including GARCH augmented with lagged trading volume and number of trades, tests based on moment restrictions, regression analysis of volatility on volume and trades, normality of returns when standardized by...

Change Agents and Collective Experience-Making as Part of ...

African Journals Online (AJOL)

agents can enable and facilitate collective learning about climate change, as well ... interconnected global problems, meaning that efforts to reduce and adapt to ..... 'acquisition of mediated experiences in the learning rhythm of the immediate ...

Trade Remedies: A Primer

National Research Council Canada - National Science Library

Jones, Vivian C

2006-01-01

The United States and many of its trading partners use laws known as trade remedies to mitigate the adverse impact of various trade practices on domestic industries and workers. U.S. antidumping laws (19 U.S.C. 1673 et seq...

Trade Remedies: A Primer

National Research Council Canada - National Science Library

Jones, Vivian C

2007-01-01

The United States and many of its trading partners use laws known as trade remedies to mitigate the adverse impact of various trade practices on domestic industries and workers. U.S. antidumping (AD) laws (19 U.S.C. 1673 et seq...

Trade Remedies: A Primer

National Research Council Canada - National Science Library

Jones, Vivian C

2008-01-01

The United States and many of its trading partners use laws known as trade remedies to mitigate the adverse impact of various trade practices on domestic industries and workers. U.S. antidumping (AD) laws (19 U.S.C. 1673 et seq...

Adaptive-network models of collective dynamics

Science.gov (United States)

Zschaler, G.

2012-09-01

. Moreover, we show what minimal microscopic interaction rules determine whether the transition to collective motion is continuous or discontinuous. Second, we consider a model of opinion formation in groups of individuals, where we focus on the effect of directed links in adaptive networks. Extending the adaptive voter model to directed networks, we find a novel fragmentation mechanism, by which the network breaks into distinct components of opposing agents. This fragmentation is mediated by the formation of self-stabilizing structures in the network, which do not occur in the undirected case. We find that they are related to degree correlations stemming from the interplay of link directionality and adaptive topological change. Third, we discuss a model for the evolution of cooperation among self-interested agents, in which the adaptive nature of their interaction network gives rise to a novel dynamical mechanism promoting cooperation. We show that even full cooperation can be achieved asymptotically if the networks' adaptive response to the agents' dynamics is sufficiently fast.

Building embodied agents that experience and express emotions

NARCIS (Netherlands)

Bui, T.D.; Magnenat-Thalmann, N.; Heylen, Dirk K.J.; Joslin, C.; Nijholt, Antinus; Kim, H.S.

2004-01-01

In this paper we presented Obie, an embodied agent that experiences and expresses emotions. Obie has an adaptive, quantitative and domain-independent emotion component which appraises events to trigger emotions. Obie’s emotions are expressed via his utterances or his facial expressions. The

Canadian Light Infantry in Adaptive Dispersed Operations

Science.gov (United States)

2012-05-22

adapted the concept to the offence by subdividing the gruppe in a light machine gun support trupp (detachment) and an assault trupp, thus creating the...They include medium and light elements that can be augmented by heavy elements if needed. According to the LO 202, light elements: “ trade a measure...the transportation of electronics equipment, weapons, and limited amounts of ammunition and supplies. All elements are helicopter transportable and

Thermal perceptions, general adaptation methods and occupant's idea about the trade-off between thermal comfort and energy saving in hot-humid regions

Energy Technology Data Exchange (ETDEWEB)

Hwang, Ruey-Lung [Department of Occupational Safety and Health, China Medical University, 91 Huseh-Shin Road, Taichung 404 (China); Cheng, Ming-Jen [Department of Architecture, Feng Chia University, 100 Wen-Hwa Road, Seatwen, Taichung 407 (China); Lin, Tzu-Ping [Department of Leisure Planning, National Formosa University, 64 Wen-Hua Road, Huwei, Yunlin 632 (China); Ho, Ming-Chin [Architecture and Building Research Institute, Ministry of the Interior, 13F, No. 200, Sec. 3, Bei-sin Road, Sindian City, Taipei County 231 (China)

2009-06-15

A field study conducted in workplaces and residences in Taiwan is carried out to clarify two questions in detail: (1) do people in the tropical climate regions demonstrate a correlation between thermal sensation and thermal dissatisfaction the same as the PMV-PPD formula in the ISO 7730; and (2) does the difference in opportunities to choose from a variety of methods to achieve thermal comfort affects thermal perceptions of occupants? A new predicted formula of percentage of dissatisfied (PD) relating to mean thermal sensation votes (TSVs) is proposed for hot and humid regions. Besides an increase in minimum rate of dissatisfied from 5% to 9%, a shift of the TSV with minimum PD to the cool side of sensation scale is suggested by the new proposed formula. It also reveals that the limits of TSV corresponding to 80% acceptability for hot and humid regions are -1.45 and +0.65 rather than -0.85 and +0.85 suggested by ISO 7730. It is revealed in the findings that the effectiveness, availability and cost of a thermal adaptation method can affect the interviewees' thermal adaptation behaviour. According to the discussion of interviewees' idea about the trade-off between thermal comfort and energy saving, it is found that an energy-saving approach at the cost of sacrificing occupant's thermal comfort is difficult to set into action, but those ensure the occupant's comfort are more acceptable and can be easily popularized. (author)

Trading network predicts stock price.

Science.gov (United States)

Sun, Xiao-Qian; Shen, Hua-Wei; Cheng, Xue-Qi

2014-01-16

Stock price prediction is an important and challenging problem for studying financial markets. Existing studies are mainly based on the time series of stock price or the operation performance of listed company. In this paper, we propose to predict stock price based on investors' trading behavior. For each stock, we characterize the daily trading relationship among its investors using a trading network. We then classify the nodes of trading network into three roles according to their connectivity pattern. Strong Granger causality is found between stock price and trading relationship indices, i.e., the fraction of trading relationship among nodes with different roles. We further predict stock price by incorporating these trading relationship indices into a neural network based on time series of stock price. Experimental results on 51 stocks in two Chinese Stock Exchanges demonstrate the accuracy of stock price prediction is significantly improved by the inclusion of trading relationship indices.

15 CFR 400.45 - Retail trade.

Science.gov (United States)

2010-01-01

... 15 Commerce and Foreign Trade 2 2010-01-01 2010-01-01 false Retail trade. 400.45 Section 400.45 Commerce and Foreign Trade Regulations Relating to Commerce and Foreign Trade (Continued) FOREIGN-TRADE ZONES BOARD, DEPARTMENT OF COMMERCE REGULATIONS OF THE FOREIGN-TRADE ZONES BOARD Zone Operations and...

Environmentally damaging electricity trade

International Nuclear Information System (INIS)

Billette de Villemeur, Etienne; Pineau, Pierre-Olivier

2010-01-01

Electricity trade across regions is often considered welfare enhancing. We show in this paper that this should be reconsidered if environmental externalities are taken into account. We consider two cases where trade is beneficial, before accounting for environmental damages: first, when two regions with the same technology display some demand heterogeneity; second when one region endowed with hydropower arbitrages with its 'thermal' neighbor. Our results show that under reasonable demand and supply elasticities, trade comes with an additional environmental cost. This calls for integrating environmental externalities into market reforms when redesigning the electricity sector. Two North American applications illustrate our results: trade between Pennsylvania and New York, and trade between hydro-rich Quebec and New York.

Online stock trading platform

Directory of Open Access Journals (Sweden)

Ion LUNGU

2006-01-01

Full Text Available The Internet is the perfect tool that can assure the market’s transparency for any user who wants to trade on the stock market. The investor can have access to the market news, financial calendar or the press releases of the issuers. A good online trading platform also provides real-time intraday quotes, trading history and technical analysis giving the investor a clearer view of the supply and demand in the market. All this information provides the investor a good image of the market and encourages him to trade. This paper wishes to draft the pieces of an online trading platform and to analyze the impact of developing and implementing one in a brokerage firm.

What makes virtual agents believable?

Science.gov (United States)

Bogdanovych, Anton; Trescak, Tomas; Simoff, Simeon

2016-01-01

In this paper we investigate the concept of believability and make an attempt to isolate individual characteristics (features) that contribute to making virtual characters believable. As the result of this investigation we have produced a formalisation of believability and based on this formalisation built a computational framework focused on simulation of believable virtual agents that possess the identified features. In order to test whether the identified features are, in fact, responsible for agents being perceived as more believable, we have conducted a user study. In this study we tested user reactions towards the virtual characters that were created for a simulation of aboriginal inhabitants of a particular area of Sydney, Australia in 1770 A.D. The participants of our user study were exposed to short simulated scenes, in which virtual agents performed some behaviour in two different ways (while possessing a certain aspect of believability vs. not possessing it). The results of the study indicate that virtual agents that appear resource bounded, are aware of their environment, own interaction capabilities and their state in the world, agents that can adapt to changes in the environment and exist in correct social context are those that are being perceived as more believable. Further in the paper we discuss these and other believability features and provide a quantitative analysis of the level of contribution for each such feature to the overall perceived believability of a virtual agent.

Gravity with Intermediate Goods Trade

Directory of Open Access Journals (Sweden)

Sujin Jang

2017-12-01

Full Text Available This paper derives the gravity equation with intermediate goods trade. We extend a standard monopolistic competition model to incorporate intermediate goods trade, and show that the gravity equation with intermediates trade is identical to the one without it except in that gross output should be used as the output measure instead of value added. We also show that the output elasticity of trade is significantly underestimated when value added is used as the output measure. This implies that with the conventional gravity equation, the contribution of output growth can be substantially underestimated and the role of trade costs reduction can be exaggerated in explaining trade expansion, as we demonstrate for the case of Korea's trade growth between 1995 and 2007.

Bitcoin trading system

OpenAIRE

Turšič, Samo

2015-01-01

In this thesis an information solution was developed that enables the implementation of different trading strategies and backtesting over cryptocurrency Bitcoin trading data. Supported exchanges are Bitstamp, BTC-e and MtGox. In the field of technical analysis there already exist various solutions for Bitcoin that help traders to trade and advise them on basis of technical indicators and patterns. However, each has its own drawbacks, which we are aiming to fix. A web application was developed...

Bitcoin trading system

OpenAIRE

Turšič, Samo