53 research outputs found
Data-intensive service provision based on particle swarm optimization
© 2018, the Authors. The data-intensive service provision is characterized by the large of scale of services and data and also the high-dimensions of QoS. However, most of the existing works failed to take into account the characteristics of data-intensive services and the effect of the big data sets on the whole performance of service provision. There are many new challenges for service provision, especially in terms of autonomy, scalability, adaptability, and robustness. In this paper, we will propose a discrete particle swarm optimization algorithm to resolve the data-intensive service provision problem. To evaluate the proposed algorithm, we compared it with an ant colony optimization algorithm and a genetic algorithm with respect to three performance metrics
Fractional Differential Equations, Inclusions and Inequalities with Applications
During the last decade, there has been an increased interest in fractional differential equations, inclusions, and inequalities, as they play a fundamental role in the modeling of numerous phenomena, in particular, in physics, biomathematics, blood flow phenomena, ecology, environmental issues, viscoelasticity, aerodynamics, electrodynamics of complex medium, electrical circuits, electron-analytical chemistry, control theory, etc. This book presents collective works published in the recent Special Issue (SI) entitled "Fractional Differential Equation, Inclusions and Inequalities with Applications" of the journal Mathematics. This Special Issue presents recent developments in the theory of fractional differential equations and inequalities. Topics include but are not limited to the existence and uniqueness results for boundary value problems for different types of fractional differential equations, a variety of fractional inequalities, impulsive fractional differential equations, and applications in sciences and engineering
Determination of an Ultimate Pit Limit Utilising Fractal Modelling to Optimise NPV
The speed and complexity of globalisation and reduction of natural resources on the one hand, and interests of large multinational corporations on the other, necessitates proper management of mineral resources and consumption. The need for scientific research and application of new methodologies and approaches to maximise Net Present Value (NPV) within mining operations is essential.
In some cases, drill core logging in the field may result in an inadequate level of information and subsequent poor diagnosis of geological phenomenon which may undermine the delineation or separation of mineralised zones. This is because the interpretation of individual loggers is subjective. However, modelling based on logging data is absolutely essential to determine the architecture of an orebody including ore distribution and geomechanical features. For instance, ore grades, density and RQD values are not included in conventional geological models whilst variations in a mineral deposit are an obvious and salient feature. Given the problems mentioned above, a series of new mathematical methods have been developed, based on fractal modelling, which provide a more objective approach. These have been established and tested in a case study of the Kahang Cu-Mo porphyry deposit, central Iran.
Recognition of different types of mineralised zone in an ore deposit is important for mine planning. As a result, it is felt that the most important outcome of this thesis is the development of an innovative approach to the delineation of major mineralised (supergene and hypogene) zones from ‘barren’ host rock. This is based on subsurface data and the utilisation of the Concentration-Volume (C-V) fractal model, proposed by Afzal et al. (2011), to optimise a Cu-Mo block model for better determination of an ultimate pit limit. Drawing on this, new approaches, referred to Density–Volume (D–V) and RQD-Volume (RQD-V) fractal modelling, have been developed and used to delineate rock characteristics in terms of density and RQD within the Kahang deposit (Yasrebi et al., 2013b; Yasrebi et al., 2014). From the results of this modelling, the density and RQD populations of rock types from the studied deposit showed a relationship between density and rock quality based on RQD values, which can be used to predict final pit slope. Finally, the study introduces a Present Value-Volume (PV-V) fractal model in order to identify an accurate excavation orientation with respect to economic principals and ore grades of all determined voxels within the obtained ultimate pit limit in order to achieve an earlier pay-back period.Institute of Materials, Minerals and Mining, the global network IOM3Cornish Institute of EngineersWhittle Consulting (Business Optimisation for the Mining Industry
A framework for the characterization and analysis of software systems scalability
The term scalability appears frequently in computing literature, but it is a term that is poorly defined and
poorly understood. It is an important attribute of computer systems that is frequently asserted but rarely
validated in any meaningful, systematic way. The lack of a consistent, uniform and systematic treatment
of scalability makes it difficult to identify and avoid scalability problems, clearly and objectively describe
the scalability of software systems, evaluate claims of scalability, and compare claims from different
sources.
This thesis provides a definition of scalability and describes a systematic framework for the characterization
and analysis of software systems scalability. The framework is comprised of a goal-oriented
approach for describing, modeling and reasoning about scalability requirements, and an analysis technique
that captures the dependency relationships that underlie typical notions of scalability. The framework
is validated against a real-world data analysis system and is used to recast a number of examples
taken from the computing literature and from industry in order to demonstrate its use across different
application domains and system designs
Adaptive Regression Methods with Application to Streaming Financial Data
This thesis is concerned with the analysis of adaptive incremental regression algorithms
for data streams. The development of these algorithms is motivated by issues
pertaining to financial data streams, data which are very noisy, non-stationary and
exhibit high degrees of dependence. These incremental regression techniques are subsequently
used to develop efficient and adaptive algorithms for portfolio allocation.
We develop a number of temporally incremental regression algorithms that have
the following attributes; efficiency: the algorithms are iterative, robustness: the algorithms
have a built-in safeguard for outliers and/or use regularisation techniques to
alleviate for estimation error, and adaptiveness: the algorithms estimation is adaptive
to the underlying streaming data. These algorithms make use of known regression
techniques: EWRLS (Exponentially Weighted Recursive Least Squares), TSVD
(Truncated Singular Value Decomposition) and FLS (Flexible Least Squares). We
focus more of our attention on a proposed robust version of EWRLS algorithm, denoted
R-EWRLS, and assess its robustness using a purpose built simulation engine.
This simulation engine is able to generate correlated data streams whose drift and
correlation change over time and can be subjected to randomly generated outliers
whose magnitudes and directions vary.
The R-EWRLS algorithm is developed further to allow for a self-tuned forgetting
factor in the formulation. The forgetting factor is an important tool to account for
non-stationarity in the data through an exponential decay profile which assigns more
weight to the more recent data. The new algorithm is assessed against the R-EWRLS
algorithm using various performance measures.
A number of applications with real data from equities and foreign exchange are used. Various measures are computed to compare our algorithms to established portfolio
allocation techniques. The results are promising and in many cases outperform
benchmark allocation techniques
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Chemical Information Bulletin
Created as a supplement for "the regular journals of the American Chemical Society," this publication contains annotated bibliographies of chemical documentation literature as well as information about meetings, conferences, awards, scholarships, and other news from the American Chemical Society (ACS) Division of Chemical Information (CINF)
The ascent of women : how female mountaineers explored the Alps 1850-1900
This thesis investigates the largely neglected history of female mountaineers
who walked and climbed in the Alps between 1850 and 1900. This discrete
group of women provide the means to re-evaluate, not only the history of
mountaineering, but also several wider issues concerning the social and cultural
understanding of middle-class women’s roles and experiences in the second half
of the nineteenth century. By closely analysing women’s mountaineering
accomplishments, this study explores their relationship to conventional ideas of
gendered ‘separate spheres’ and the female as the ‘weaker sex.’ The
demonstration of physical ability and the adoption of ‘alternative’ lifestyles by
women mountaineers suggest normal rules of propriety were frequently waived.
Analysing the circumstances these particular women embraced, casts a new light
on the alleged constraints of Victorian femininity.
The work focuses upon the status, perception and use of the female body,
physically and emotionally, in a given environment. It is particularly concerned
with women’s own agency and with the assessment of how far female climbers
ignored society’s expectations. These issues are considered against the backdrop
of powerful cultural ‘norms’ that affected the perception of middle-class
women’s ‘natural’ abilities and aptitudes. The thesis reveals how women
constituted a distinct, autonomous and active presence within the mountains,
and undertook challenging, sometimes unprecedented ascents, occasionally in
advance of men. At a time when climbing was widely perceived as ‘manly’, the
thesis asks how far women accepted this mantle and how far they retained a
distinctive feminine identity. The study suggests a more fluid and less confining
vision of femininity emerged, at least in the mountains, for many middle-class
Victorian women. Finally, the thesis considers a variety of historical as well as
historiographical factors that have contributed to the occlusion of women’s life
experiences both generally and specifically from the history of Alpinism
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