scholarly journals Evaluating Auction Mechanisms for the Preservation of Cost-Aware Digital Objects under Constrained Digital Preservation Budgets

Mathematics ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 92
Author(s):  
Andres El-Fakdi ◽  
Josep Lluis de la Rosa

Digital preservation is a field of research focused on designing strategies for maintaining digital objects accessible for general use in the coming years. Out of the many approaches to digital preservation, the present research article is a continuation work of a previously published article containing a proposal for a novel object-centered paradigm to address the digital preservation problem where digital objects share part of the responsibility for self-preservation. In the new framework, the behavior of digital objects is modeled to find the best preservation strategy. The results presented in the current article add a new economic constraint to the object behavior. Now, differently from the previous paper, migrations, copies and updates are not free to use, but subject to budget limitations to ensure the economic sustainability of the whole preservation system, forcing the now-called cost-aware digital objects for efficient management of available budget. The presented approach compares two auction-based mechanisms, a multi-unit auction and a combinatorial auction, with a simple direct purchase strategy as possible efficient behaviors for budget management. TiM, a simulated environment for running distributed digital ecosystems, is used to perform the experiments. The simulated results map the relation between the studied purchase models with the sustained quality level of digital objects, as a measure of its accessibility, together with its budget management capabilities. About the results, the best performance corresponds to the combinatorial auction model. The results are a good approach to deal with the digital preservation problem from a sustainable point of view and open the door to future implementations with other purchase strategies.

Mathematics ◽  
2021 ◽  
Vol 9 (18) ◽  
pp. 2279
Author(s):  
Andres El-Fakdi ◽  
Josep Lluis de la Rosa

Digital preservation is a research area devoted to keeping digital assets preserved and usable for many years. Out of the many approaches to digital preservation, the present research article follows a new object-centered digital preservation paradigm where digital objects share part of the responsibility for preservation: they can move, replicate, and evolve to a higher-quality format inside a digital ecosystem. In the new framework, the behavior of digital objects needs to be modeled in order to obtain the best preservation strategy. Thus, digital objects are programmed with the mission of their own long-term self-preservation, which entails being accessible and reproducible by users at any time in the future regardless of frequent technological changes due to software and hardware upgrades. Three nature-inspired computational intelligence algorithms, based on the collective behavior of decentralized and self-organized systems, were selected for the modeling approach: multipopulation genetic algorithm, ant colony optimization, and a virus-based algorithm. TiM, a simulated environment for running distributed digital ecosystems, was used to perform the experiments. The results map the relation between the models and the expected object diversity obtained in short- and mid-term digital preservation scenarios. Comparing the results, the best performance corresponded to the multipopulation genetic algorithm. The article aims to be a first step in the digital self-preservation field. Building nature-inspired model behaviors is a good approach and opens the door to future tests with other AI-based methods.


1967 ◽  
Vol 7 (3) ◽  
pp. 416-420
Author(s):  
Arthur MacEwan

These books are numbers 4 and 5, respectively, in the series "Studies in the Economic Development of India". The two books are interesting complements to one another, both being concerned with the analysis of projects within national plan formulation. However, they treat different sorts of problems and do so on very different levels. Marglin's Public Investment Criteria is a short treatise on the problems of cost-benefit analysis in an Indian type economy, i.e., a mixed economy in which the government accepts a large planning responsibility. The book, which is wholely theoretical, explains the many criteria needed for evaluation of projects. The work is aimed at beginning students and government officials with some training in economics. It is a clear and interesting "introduction to the special branch of economics that concerns itself with systematic analysis of investment alternatives from the point of view of a government".


Morphology ◽  
2021 ◽  
Author(s):  
Rossella Varvara ◽  
Gabriella Lapesa ◽  
Sebastian Padó

AbstractWe present the results of a large-scale corpus-based comparison of two German event nominalization patterns: deverbal nouns in -ung (e.g., die Evaluierung, ‘the evaluation’) and nominal infinitives (e.g., das Evaluieren, ‘the evaluating’). Among the many available event nominalization patterns for German, we selected these two because they are both highly productive and challenging from the semantic point of view. Both patterns are known to keep a tight relation with the event denoted by the base verb, but with different nuances. Our study targets a better understanding of the differences in their semantic import.The key notion of our comparison is that of semantic transparency, and we propose a usage-based characterization of the relationship between derived nominals and their bases. Using methods from distributional semantics, we bring to bear two concrete measures of transparency which highlight different nuances: the first one, cosine, detects nominalizations which are semantically similar to their bases; the second one, distributional inclusion, detects nominalizations which are used in a subset of the contexts of the base verb. We find that only the inclusion measure helps in characterizing the difference between the two types of nominalizations, in relation with the traditionally considered variable of relative frequency (Hay, 2001). Finally, the distributional analysis allows us to frame our comparison in the broader coordinates of the inflection vs. derivation cline.


2001 ◽  
Vol 11 (4) ◽  
pp. 311-321
Author(s):  
DN Carmichael ◽  
Michael Lye

Heart failure has been defined in many ways and definitions change over time. The multiplicity of definitions reflect the paucity of our understanding of the primary underlying physiology of heart failure and the many diseases for which heart failure is the common end-point. Fundamentally, heart failure represents a failure of the heart to meet the body’s requirement for blood supply for whatever reason. It is thus a clinical syndrome with characteristic features – not a single disease in its own right. The syndrome includes symptoms and signs of organ underperfusion, fluid retention and neuroendocrine activation. The syndrome arises from a range of possible causes of which ischaemic heart disease is the commonest. From the point of view of a clinician, the underlying pathology will determine treatment options and prognosis. The extensive range of possible aetiologies present a diagnostic challenge both to correctly identify the syndrome amongst all other causes of dyspnoea and to identify the aetiology, allowing optimization of treatment.


PEDIATRICS ◽  
1971 ◽  
Vol 48 (4) ◽  
pp. 629-635
Author(s):  
Howard A. Pearson ◽  
Louis K. Diamond

This brief review, being limited in scope to the recognition and management of the life-threatening and painful crises in infants and children with sickle-cell disease, has not even touched on the intriguing mystery of the molecular basis for the sickling phenomenon–how one amino-acid substitution (gene controlled) in the beta chain sequence of 146 amino acids can cause such serious disruption in form and function; or how this mutation occurred in the first place and why it has persisted in contrast to the rapid disappearance of many other deleterious mutants. Nor has there been even mention of the many milder symptoms, signs, and complications due to the presence of Hb. S., either in the homozygous (disease-producing) state or heterozygous form when found in combination with other hereditary hemoglobin defects. The accumulated knowledge about this mutant gene, its biochemical effects, and geographic distribution is enormous. From a fundamental scientific standpoint, sickle cell disease is one of the best understood of human afflictions. However, from a practical point of view treatment of the patient himself is often only symptomatic and palliative. Nevertheless, prompt and effective therapy of the myriad manifestations of sickle cell disease can effectively reduce morbidity and mortality. The pediatrician who cares for black children in his practice should be familiar with the cardinal diagnostic and clinical aspects of sickle cell disease and its crises.


PEDIATRICS ◽  
1950 ◽  
Vol 6 (3) ◽  
pp. 553-556

THE road to better child health has been discussed in relation to the doctor and his training, health services and their distribution. We have dealt with the unavoidable question of costs. Particular attention has been given to some of the advantages and dangers of decentralization of pediatric education and services. Each of the various subjects has been discussed from the point of view of its bearing on the ultimate objective of better health for all children and the steps necessary to attain this goal. Now, we may stand back from the many details of the picture, view the whole objectively and note its most outstanding features. First is the fact that the improvement of child health depends primarily upon better training for all doctors who provide child care, general practitioners as well as specialists. This is the foundation without which the rest of the structure cannot stand. The second dominant fact is the need for extending to outlying and isolated areas the high quality medical care of the medical centers, without at the same time diluting the service or training at the center. The road to better medical care, therefore, begins at the medical center and extends outward through a network of integrated community hospitals and health centers, finally reaching the remote and heretofore isolated areas. Inherent in all medical schools is a unique potential for rendering medical services as well as actually training physicians. The very nature of medical education—whereby doctors in training work under the tutelage of able specialists in the clinic, hospital ward, and out-patient department—provides medical services of high quality to people in the neighboring communities.


2020 ◽  
Author(s):  
Kochikpa Ondodje

Abstract The SARL "Pobè Fish Farm" located in the South-East of Benin specializes in the production and sale of tilapia and Clarias. The farm has twenty two ponds of 200 m2 (10 m × 20 m) supplied with water by a pipe system from a natural and permanent stream. The water supply is via a concrete channel which did not allow the water to be renewed once the pond is full. Work has been carried out to allow a larger inflow of water and communication between the ponds. The operation of the farm is modeled on the types of agro-fish farms existing in Asia and encountered in Vietnam in particular; it aims to put theoretical knowledge into practice and on the other hand to contribute to the development of a sector still little known in Benin, despite the many hydroagricultural potentials with which this country is endowed. The species bred at national level are rustic and adapted to the environment and whose genetic performance has not been improved. In fact, only modern breeding following very precise technical standards can allow obtaining interesting results from the point of view of agronomic yield and financial profitability. Indeed, these fish from our ponds are very popular with the populations (the average wholesale price is 1000 FCFA/kg) and are already an integral part of eating habits both in rural areas and in cities.


2018 ◽  
Vol 170 ◽  
pp. 03017 ◽  
Author(s):  
Alexey Dmitriev ◽  
Vyacheslav Gerasimov

The expediency of using a variable frequency drive for pumping units was repeatedly proved both from the point of view of the economic component and the technological one. However, the construction of automatic control systems for the operating parameters of pumping stations is mainly based on maintaining the pressure setpoint and does not include monitoring the efficiency of the aggregates working in the group and, the more so, its regulation. In this paper, an algorithm is developed for the energy efficient management of centrifugal pump units, which allows not only maintaining the pressure setpoint, but also optimizing their efficiency.


Author(s):  
Gareth Kay ◽  
Libor Coufal ◽  
Mark Pearson

This article introduces the National Library of Australia’s Digital Preservation Knowledge Base which helps the Library to manage digital objects from its collections over the long term. The Knowledge Base includes information on file formats, rendering software, operating systems, hardware and, most importantly, the relationships between them. Most of the work on the Knowledge Base over the last few years has been focused on the mapping of functional relationships between file formats, their versions and software applications. The information is gathered through unique empirical research and is initially being recorded in a multiple-worksheet Excel file in a semi-structured format, though development of a prototype graph database is underway.


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