Task Allocation (task + allocation)

Distribution by Scientific Domains


Selected Abstracts


Foraging for Work and Age-Based Polyethism: The Roles of Age and Previous Experience on Task Choice in Ants

ETHOLOGY, Issue 11 2004
Frederic Tripet
In social insects, colonies commonly show temporal polyethism in worker behavior, such that a worker follows a predictable pattern of changes between tasks as it ages. This pattern usually leads from workers first doing a safe task like brood care, to ending their lives doing the most dangerous tasks like foraging. Two mechanisms could potentially underlie this pattern: (1) age-based task allocation, where the aging process itself predisposes workers to switch to more dangerous tasks; and (2) foraging for work, where ants switch to tasks that need doing from tasks which have too many associated workers. We tested the relative influence of these mechanisms by establishing nests of Camponotus floridanus with predetermined combinations of workers of known age and previous task specialization. The results supported both mechanisms. Nests composed of entirely brood-tending workers had the oldest workers preferentially switching to foraging. However, in nests initially composed entirely of foragers, the final distribution of tenders and foragers was not different from random task-switching and therefore supportive of foraging for work. Thus, it appears that in C. floridanus there is directionality to the mechanisms of task allocation. Switching to more dangerous tasks is age-influenced, but switching to less dangerous tasks is age-independent. The results also suggest that older workers are more flexible in their task choice behavior. Younger workers are more biased towards choosing within-nest tasks. Finally, there are effects of previous experience that tend to keep ants in familiar tasks. Task allocation based on several mechanisms may balance between: (1) concentrating the most worn workers into the most dangerous tasks; (2) increasing task performance levels; and (3) maintaining behavioral flexibility to respond to demographic perturbations. The degree to which behavior is flexible may correlate to the frequency of such perturbations in a species. [source]


COALITIONS AMONG INTELLIGENT AGENTS: A TRACTABLE CASE

COMPUTATIONAL INTELLIGENCE, Issue 1 2006
M. V. Belmonte
Coalition formation is an important mechanism for cooperation in multiagent systems. In this paper we address the problem of coalition formation among self-interested agents in superadditive task-oriented domains. We assume that each agent has some "structure," i.e., that it can be described by the values taken by a set of m nonnegative attributes that represent the resources w each agent is endowed with. By defining the coalitional value as a function V of w, we prove a sufficient condition for the existence of a stable payment configuration,in the sense of the core,in terms of certain properties of V. We apply these ideas to a simple case that can be described by a linear program and show that it is possible to compute for it,in polynomial time,an optimal task allocation and a stable payment configuration. [source]


Experiments on robustness and deception in a coalition formation model

CONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 4 2006
M. V. Belmonte
Abstract In the last few years coalition formation algorithms have been proposed as a possible way of modeling autonomous agent cooperation in multi-agent systems. This work is based on a previously proposed coalition formation model founded on game theory for a class of task-oriented problems that guarantees an optimum task allocation and a stable profit division. In this paper we study two properties of the model that are very important for application in real-life scenarios: robustness and tolerance to an agent's misbehavior. First, we study the robustness of this model as regards the effect the agent's failure has on the resultant profits of the coalition formation. Secondly, we also study the coalition formation model in the presence of misbehaving agents. Agents have some kind of execution autonomy, and they can deceive or mislead each other when they reveal their information, if they believe this will give them more profits. Copyright © 2005 John Wiley & Sons, Ltd. [source]


Unequal Knowledges in Jharkhand, India: De-Romanticizing Women's Agroecological Expertise

DEVELOPMENT AND CHANGE, Issue 5 2000
Sarah Jewitt
Taking the Jharkhand region of India as a case study, this article uses empirical data to intervene in ,women, environment and development' and ecofeminist debates regarding women's environmental knowledge. The article first outlines the adoption of gender/environmental issues into development planning and considers the dangers of overestimating women's agroecological knowledges and assuming that they can easily participate in development projects. It then highlights the local complexities of environmental knowledge possession and control with reference to gender and other variations in agricultural participation, decision-making and knowledge transfers between villagers' natal and marital places. Particular emphasis is placed on the economic, socio-cultural and ,actor' related factors that supplement gender as an influence on task allocation, decision-making, knowledge distribution and knowledge articulation. The article concludes that given the socio-cultural constraints women face in accumulating and vocalizing environmental knowledge, simplistic participatory approaches are unlikely to empower them. Instead, more flexible, site-specific development initiatives (coupled with wider structural change) are required if opportunities are to be created for women to develop and use their agroecological knowledges. [source]


Foraging for Work and Age-Based Polyethism: The Roles of Age and Previous Experience on Task Choice in Ants

ETHOLOGY, Issue 11 2004
Frederic Tripet
In social insects, colonies commonly show temporal polyethism in worker behavior, such that a worker follows a predictable pattern of changes between tasks as it ages. This pattern usually leads from workers first doing a safe task like brood care, to ending their lives doing the most dangerous tasks like foraging. Two mechanisms could potentially underlie this pattern: (1) age-based task allocation, where the aging process itself predisposes workers to switch to more dangerous tasks; and (2) foraging for work, where ants switch to tasks that need doing from tasks which have too many associated workers. We tested the relative influence of these mechanisms by establishing nests of Camponotus floridanus with predetermined combinations of workers of known age and previous task specialization. The results supported both mechanisms. Nests composed of entirely brood-tending workers had the oldest workers preferentially switching to foraging. However, in nests initially composed entirely of foragers, the final distribution of tenders and foragers was not different from random task-switching and therefore supportive of foraging for work. Thus, it appears that in C. floridanus there is directionality to the mechanisms of task allocation. Switching to more dangerous tasks is age-influenced, but switching to less dangerous tasks is age-independent. The results also suggest that older workers are more flexible in their task choice behavior. Younger workers are more biased towards choosing within-nest tasks. Finally, there are effects of previous experience that tend to keep ants in familiar tasks. Task allocation based on several mechanisms may balance between: (1) concentrating the most worn workers into the most dangerous tasks; (2) increasing task performance levels; and (3) maintaining behavioral flexibility to respond to demographic perturbations. The degree to which behavior is flexible may correlate to the frequency of such perturbations in a species. [source]


System design in normative and actual practice: A comparative study of cognitive task allocation in advanced manufacturing systems

HUMAN FACTORS AND ERGONOMICS IN MANUFACTURING & SERVICE INDUSTRIES, Issue 2 2004
Sotiris Papantonopoulos
The Human Factors Engineering approach to human-machine system design is based largely on normative design methods. This article suggests that the scope of Human Factors Engineering shall be extended to the descriptive study of system design in actual practice by the application of theoretical frameworks that emphasize the role of the system-design practitioner and organization in the design process. A comparative study of system design in normative and actual practice was conducted in the design of cognitive task allocation in a Flexible Manufacturing System (FMS) cell. The study showed that the designers' allocation decisions were influenced strongly by factors related to their own design practices, yet exogenous to the tasks to be allocated. Theoretical frameworks from Design Research were applied to illustrate differences between normative and actual practice of system design. © 2004 Wiley Periodicals, Inc. Hum Factors Man 14: 181,196, 2004. [source]