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Finite Resources (finite + resource)
Selected AbstractsResource management in open Linda systemsCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 13 2003Ronaldo Menezes Abstract Coordination systems, in particular Linda, have established themselves as important tools for the development of applications to open systems such as the Internet. This paper shows how to tackle a forgotten, but crucial problem in open coordination systems: memory management. As with any system which intends to be of wide use and because memory is a finite resource, coordination systems must address the problems of memory exhaustion. This paper first explores the orthogonality between coordination and computation in order to make it clear that the problem of memory exhaustion in coordination systems cannot be solved using garbage collection schemes implemented at the computation language,a garbage collection scheme must exist in the coordination environment as well. Following the explanation on orthogonality, the paper will focus on describing a garbage collection scheme for the Linda family of coordination systems. It is expected that the solution in Linda can be adapted to other coordination systems as long as they are based on tuple space communication. Copyright © 2003 John Wiley & Sons, Ltd. [source] A model of sequential effects in common pool resource dilemmasJOURNAL OF BEHAVIORAL DECISION MAKING, Issue 1 2002David V. Budescu Abstract Experimental games are often used as models of social dilemmas in which small groups of players have unrestricted access to, and share, a common and finite resource of desirable goods in the absence of any binding coordination mechanism. Examples are fishing, hunting, and use of computational facilities. Experimental studies of social dilemmas employ different protocols of play that differ from each other in terms of the information available to the players when they register their requests from the common resource. In this study we focus on the sequential protocol, where each participant has complete information about his or her position and the total requests of the previous movers, and the positional protocol, where each player only knows his or her position, but has no information about the other's requests. Previous research has found a robust position effect: individual requests are inversely related to the players' positions in the sequence with the first mover requesting most, and the last mover requesting the least. In an attempt to characterize the nature and intensity of the position effect, we developed and tested a descriptive model with one free (individual specific) parameter. The parameter is estimated from the players' requests under the positional protocol (i.e. in the absence of any information about the other's requests) and, as such, quantifies the social norm of ,advantage of the early mover'. In a range of cases examined, including different group sizes, resource pool sizes, and positions, the model predicted very accurately individuals' requests in the sequential protocol (with full information about position and others' requests). Copyright © 2002 John Wiley & Sons, Ltd. [source] The Effect of Male Incubation Feeding, Food and Temperature on the Incubation Behaviour of New Zealand RobinsETHOLOGY, Issue 6 2010Rebecca L. Boulton Because of finite resources, organisms face conflict between their own self-care and reproduction. This conflict is especially apparent in avian species with female-only incubation, where females face a trade-off between time allocated to their own self-maintenance and the thermal requirements of developing embryos. We recorded incubation behaviour of the New Zealand robin (Petroica longipes), a species with female-only incubation, male incubation feeding and high nest predation rates. We examined how male incubation feeding, ambient temperature and food availability (invertebrate biomass) affected the different components of females' incubation behaviour and whether incubation behaviour explained variation in nest survival. Our results suggest that male incubation feeding rates of 2.8 per hour affect the female's incubation rhythm by reducing both on- and off-bout duration, resulting in no effect on female nest attentiveness, thus no support for the female-nutritional hypothesis. The incubation behaviours that we measured did not explain nest survival, despite high nest predation rates. Increased ambient temperature caused an increase in off-bout duration, whereas increased food availability increased on-bout duration. While males play a vital role in influencing incubation behaviour, female robins attempt to resolve the trade-off between their own foraging needs and the thermal requirements of their developing embryos via alternating their incubation rhythm in relation to both food and temperature. [source] The carrying capacity of ecosystemsGLOBAL ECOLOGY, Issue 6 2004Pablo Del Monte-Luna ABSTRACT We analyse the concept of carrying capacity (CC), from populations to the biosphere, and offer a definition suitable for any level. For communities and ecosystems, the CC evokes density-dependence assumptions analogous to those of population dynamics. At the biosphere level, human CC is uncertain and dynamic, leading to apprehensive rather than practical conclusions. The term CC is widely used among ecological disciplines but remains vague and elusive. We propose the following definition: the CC is ,the limit of growth or development of each and all hierarchical levels of biological integration, beginning with the population, and shaped by processes and interdependent relationships between finite resources and the consumers of those resources'. The restrictions of the concept relate to the hierarchical approach. Emergent properties arise at each level, and environmental heterogeneity restrains the measurement and application of the CC. Because the CC entails a myriad of interrelated, ever-changing biotic and abiotic factors, it must not be assumed constant, if we are to derive more effective and realistic management schemes. At the ecosystem level, stability and resilience are dynamic components of the CC. Historical processes that help shape global biodiversity (e.g. continental drift, glaciations) are likely drivers of large-scale changes in the earth's CC. Finally, world population growth and consumption of resources by humanity will necessitate modifications to the paradigm of sustainable development, and demand a clear and fundamental understanding of how CC operates across all biological levels. [source] Refusing analgesics: using continuous improvement to improve pain management on a surgical wardJOURNAL OF CLINICAL NURSING, Issue 6 2002Eloise C. J. Carr BSc, PGCEA Summary , ,Despite advances in pain control many patients experience moderate to severe pain whilst in hospital. Contributory factors include inadequate assessment and documentation of pain, as well as patient and professional misconceptions. , ,A 28-bedded surgical ward in a District General Hospital in the South of England was the setting for the project. A small preliminary audit of pain on this ward indicated that some patients experienced postoperative pain, which was not effectively controlled. A ,continuous improvement' framework was used to increase understanding of the problem and identify an aim for the project, which was to reduce the number of patients refusing analgesics when offered by nurses. , ,An audit to ascertain how many patients refused analgesia revealed that, of 133 patients offered, 93 (70%) refused. Using the ,Model for Improvement' (Langley et al., 1996) a number of changes were introduced, including a patient information sheet, regular documented pain assessment and an innovative staff education programme. To evaluate if the changes in practice had been successful, further audit data were collected from 167 patients. Sixty-three (44%) accepted analgesics, indicating a significant decrease in the number refusing (P = 0.005). , ,This small project demonstrated that continuous improvement methodology can improve the management of pain and quality of care for patients. Such an approach brings practitioner and patient into meaningful understanding and offers solutions which are realistic, achievable and sustainable over time. Despite finite resources and increased pressure on staff it is possible to motivate people when they feel they have ownership and change is meaningful. , ,Continuous improvement methods offer an exciting, feasible, patient-centred approach to improving care. [source] Intuitive Lawmaking: The Example of Child SupportJOURNAL OF EMPIRICAL LEGAL STUDIES, Issue 1 2009Ira Mark Ellman Setting the amount of a child support award involves tradeoffs in the allocation of finite resources among at least three private parties: the two parents, and their child or children. Federal law today requires states to have child support guidelines or formulas that determine child support amounts on a uniform statewide basis. These state guidelines differ in how they make these unavoidable tradeoffs. In choosing the correct balance of these competing claims, policymakers would do well to understand the public's intuitions about the appropriate tradeoffs. We report an empirical study of lay intuitions about these tradeoffs, which we compare to the principles underlying typical state guidelines. As in other contexts in which people are asked to place a dollar value on a legal claim, we find that citizen assessments of child support for particular cases conform to the pattern that Ariely and his co-authors have called "coherent arbitrariness": the respondent's choice of dollar magnitude may be arbitrary, but relative values respond coherently to case variations, within and across citizens. These patterns also suggest that our respondents have a consistent and systematic preference with respect to the structure of child support formulas that differs in important ways from either of the two systems adopted by nearly all states. [source] Tackling diabetes pregnancy care with finite resources: a tough challengePRACTICAL DIABETES INTERNATIONAL (INCORPORATING CARDIABETES), Issue 2 2008ML Wong, et al. No abstract is available for this article. [source] Recombinant protein expression and solubility screening in Escherichia coli: a comparative studyACTA CRYSTALLOGRAPHICA SECTION D, Issue 10 2006Nick S. Berrow Producing soluble proteins in Escherichia coli is still a major bottleneck for structural proteomics. Therefore, screening for soluble expression on a small scale is an attractive way of identifying constructs that are likely to be amenable to structural analysis. A variety of expression-screening methods have been developed within the Structural Proteomics In Europe (SPINE) consortium and to assist the further refinement of such approaches, eight laboratories participating in the network have benchmarked their protocols. For this study, the solubility profiles of a common set of 96 His6 -tagged proteins were assessed by expression screening in E. coli. The level of soluble expression for each target was scored according to estimated protein yield. By reference to a subset of the proteins, it is demonstrated that the small-scale result can provide a useful indicator of the amount of soluble protein likely to be produced on a large scale (i.e. sufficient for structural studies). In general, there was agreement between the different groups as to which targets were not soluble and which were the most soluble. However, for a large number of the targets there were wide discrepancies in the results reported from the different screening methods, which is correlated with variations in the procedures and the range of parameters explored. Given finite resources, it appears that the question of how to most effectively explore `expression space' is similar to several other multi-parameter problems faced by crystallographers, such as crystallization. [source] | |||||||||||||