209,369 research outputs found
Collective Motion of Predictive Swarms
Theoretical models of populations and swarms typically start with the
assumption that the motion of agents is governed by the local stimuli. However,
an intelligent agent, with some understanding of the laws that govern its
habitat, can anticipate the future, and make predictions to gather resources
more efficiently. Here we study a specific model of this kind, where agents aim
to maximize their consumption of a diffusing resource, by attempting to predict
the future of a resource field and the actions of other agents. Once the agents
make a prediction, they are attracted to move towards regions that have, and
will have, denser resources. We find that the further the agents attempt to see
into the future, the more their attempts at prediction fail, and the less
resources they consume. We also study the case where predictive agents compete
against non-predictive agents and find the predictors perform better than the
non-predictors only when their relative numbers are very small. We conclude
that predictivity pays off either when the predictors do not see too far into
the future or the number of predictors is small.Comment: 16 pages, 7 figure
Identification of target system operations. 1. Determination of the time of the actual completion of the target operation
It was found in the paper that the time frames of the studied system
operation depend on the research objective. In cases when it comes to problems,
related to the physical movement of the input and output products, limits of
the study are defined by the time of the beginning of the movement of the first
input product of the operation and ends with the time of issue of the last
output product of the operation by the system. Time of completion of the
physical movement of products is defined in the paper as the time of the
physical completion of the operation. Since the purpose of any operation is to
increase the value of the output products in relation to the value of input
products of the operation, in cases when there is a problem of investigating
the target operation, the time of completion of the target operation is
determined not by the physics of the process, but its cybernetics. Since for
the time of the operation, conversion processes link input products in time,
the added value of output products is intended to compensate in time the costs
of temporary binding of input products that initially have their value. The
time, when the added value of output products of the target operation
compensates the value of tight input products for the time of the operation, is
defined in the paper as the time of the actual completion of the target
operation. A system of notations to describe the system processes of target
operations was proposed. The expressions for the numerical and analytical
determination of the time of actual completion of the target operation were
obtained. A link to the resource, with examples of calculations of the time of
the actual completion of the operation with the use of numerical methods and
analytic expressions, obtained in the paper was given.Comment: 6 pages, 6 figure
Approximation Algorithms for Energy Minimization in Cloud Service Allocation under Reliability Constraints
We consider allocation problems that arise in the context of service
allocation in Clouds. More specifically, we assume on the one part that each
computing resource is associated to a capacity constraint, that can be chosen
using Dynamic Voltage and Frequency Scaling (DVFS) method, and to a probability
of failure. On the other hand, we assume that the service runs as a set of
independent instances of identical Virtual Machines. Moreover, there exists a
Service Level Agreement (SLA) between the Cloud provider and the client that
can be expressed as follows: the client comes with a minimal number of service
instances which must be alive at the end of the day, and the Cloud provider
offers a list of pairs (price,compensation), this compensation being paid by
the Cloud provider if it fails to keep alive the required number of services.
On the Cloud provider side, each pair corresponds actually to a guaranteed
success probability of fulfilling the constraint on the minimal number of
instances. In this context, given a minimal number of instances and a
probability of success, the question for the Cloud provider is to find the
number of necessary resources, their clock frequency and an allocation of the
instances (possibly using replication) onto machines. This solution should
satisfy all types of constraints during a given time period while minimizing
the energy consumption of used resources. We consider two energy consumption
models based on DVFS techniques, where the clock frequency of physical
resources can be changed. For each allocation problem and each energy model, we
prove deterministic approximation ratios on the consumed energy for algorithms
that provide guaranteed probability failures, as well as an efficient
heuristic, whose energy ratio is not guaranteed
Value and utility in a historical perspective
Since value and utility are the highest profile abstractions that underlie an epoch’s intellectual climate and ethical principles, their evolution reflects the transformation of socioeconomic conditions and institutions. The “Classical Phase” flourished during the first global system, laissez-faire/metal money/zero multilateralism (GS1); the second, “Subjective/Utilitarian” phase marked the long transition to the current epoch of “Modern Subjectivism/General Equilibrium,” tied to the second and extant global system, mixed economy/minimum reserve banking/weak multilateralism (GS2). History has witnessed the material de-essentialization of value and substantialization of utility. But now the two concepts face a thorough transvaluation as the world’s combined demographic and economic expansion encounters ecological/physical limitations. An extended macrohistoric implosion may lead to a third form of global self-organization: two-level economy/maximum bank reserve money/strong multilateralism (GS3). If history unfolds along the suggested path, not only economics, but also thinking about economics would change. It would be considered an evolving hermeneutic of the human condition expressed through global-system-specific texts. The implied critical alteration, with the recognition of the entropy law’s importance as its focal point, matches the prediction of Swiss thinker Jean Gebser (1905-1973) about the impending mutation of human consciousness into its integral/arational structure. Such extrapolations form the context in which the fourth historical phase of value and utility is hypothesized, leading to the material re-essentialization of value and de-substantialization of utility
On the global economic potentials and marginal costs of non-renewable resources and the price of energy commodities
A model is presented in this work for simulating endogenously the evolution
of the marginal costs of production of energy carriers from non-renewable
resources, their consumption, depletion pathways and timescales. Such marginal
costs can be used to simulate the long term average price formation of energy
commodities. Drawing on previous work where a global database of energy
resource economic potentials was constructed, this work uses cost distributions
of non-renewable resources in order to evaluate global flows of energy
commodities. A mathematical framework is given to calculate endogenous flows of
energy resources given an exogenous commodity price path. This framework can be
used in reverse in order to calculate an exogenous marginal cost of production
of energy carriers given an exogenous carrier demand. Using rigid price
inelastic assumptions independent of the economy, these two approaches generate
limiting scenarios that depict extreme use of natural resources. This is useful
to characterise the current state and possible uses of remaining non-renewable
resources such as fossil fuels and natural uranium. The theory is however
designed for use within economic or technology models that allow technology
substitutions. In this work, it is implemented in the global power sector model
FTT:Power. Policy implications are given.Comment: 18 pages, 7 figures, 8 pages of supplementary informatio
A conceptual framework for circular design
Design has been recognised in the literature as a catalyst to move away from the traditional model of take-make-dispose to achieve a more restorative, regenerative and circular economy. As such, for a circular economy to thrive, products need to be designed for closed loops, as well as be adapted to generate revenues. This should not only be at the point of purchase, but also during use, and be supported by low-cost return chains and reprocessing structures, as well as effective policy and regulation. To date, most academic and grey literature on the circular economy has focused primarily on the development of new business models, with some of the latter studies addressing design strategies for a circular economy, specifically in the area of resource cycles and design for product life extension. However, these studies primarily consider a limited spectrum of the technical and biological cycles where materials are recovered and restored and nutrients (e.g., materials, energy, water) are regenerated. This provides little guidance or clarity for designers wishing to design for new circular business models in practice. As such, this paper aims to address this gap by systematically analysing previous literature on Design for Sustainability (DfX) (e.g., design for resource conservation, design for slowing resource loops and whole systems design) and links these approaches to the current literature on circular business models. A conceptual framework is developed for circular economy design strategies. From this conceptual framework, recommendations are made to enable designers to fully consider the holistic implications for design within a circular economy
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