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A Decision Support System for Integrated Airport Performance Assessment and Capacity Management
No full textNotwithstanding the global economic crisis, long-term forecasts of air transport growth
speak about a doubling in air transport demand in Europe by 2030 (Eurocontrol, 2008).
Characteristically, although the planned capacity of 138 Eurocontrol Statistical Reference
Area (ESRA) airports is planned to increase by 41% in total by 2030, the demand will still
exceed capacity of the airport system by as many as 7.0 million flights in a high-growth
scenario
for 2030 (Eurocontrol, 2008). Under such a scenario, 14–39 European airports will
need to operate at full capacity 8 h per day to accommodate only a part of the demand, similar
to what most severely congested airports do now (Eurocontrol, 2008). A direct consequence
of the mismatch between capacity and traffic growth is the increase of congestion and delays
both in the air and on the ground (at airports). Airports constitute the terminal nodes of
a continuously
expanding air transport network that should both efficiently and safely
accommodate
growing traffic.
The anticipated traffic growth in decades to come will again push capacity to the limit, thus
triggering unprecedented levels of congestion with far reaching impact on the environment
and the safety of operations. The latter concerns will pose serious challenges towards close
airport performance monitoring and improvement. Airport decision makers should be able
to cope with multiple – even conflicting – objectives and priorities assigned by various
stakeholders
regarding the multifaceted performance of the airport system such as the level
of service offered to the travelling public, the efficiency of airport and air traffic management
(ATM) operations, the quality of the surrounding environment, and the safety of the entire air
transport system. The assessment of the airport performance requires a deep understanding
of the manifold aspects of airport performance supported by advanced modelling capabilities
and decision support systems, or tools for measuring it. Such decision aids should be diverse
in that they should: (1) capture the behaviour of various entities (e.g. aircraft, passenger,
baggage)
processed through the system, (2) address different airport elements simultaneously
(e.g. runway system, taxiway system, apron area, terminal), and (3) consider a large set of
airport performance measures like capacity, delays, safety, security, noise and costs.
In order to deal with the multi-faceted aspects of the airport decision making process, a
wealth of decision support models and tools have appeared in both literature and practice
(Odoni, 1991; Tosic, 1992; Odoni et al., 1997; Lucic et al., 2007; Correia et al., 2008; Long
et al., 2009). Early modelling efforts developed rather focused applications (e.g. models, tools)
both in terms of integration scope and degree of coverage. They basically constituted ‘monolithic’
modelling structures exhibiting either analytical or simulation modelling approaches
with focused decision support capabilities mainly with view to a single airport performance
measure, for example, runway capacity (not accounting for trade-offs). At the same time, early
modelling efforts had a targeted/narrow coverage of specific elements of either airside (mainly
runways) or landside. Since their early stages of development in the 1960s, airport performance
models and tools have evolved substantially with a common orientation
being the pursuit of
more integration and expanded coverage capabilities. More recent research initiatives since
1990s attempted the integration of pre-selected and pre-existing
tool configurations in order to
model and evaluate simultaneously airport airside and landside and assess their interdependencies
(Andreatta et al., 1999; Zografos and Madas, 2006). These efforts primarily suffered
from the lack of a harmonized, fully integrated and automated computing environment needed
to execute the various models, as well as limited trade-off analysis capabilities.
Despite the rich experience in both models and tools for airport performance assessment,
modelling capabilities until 10 years ago or so addressed only partial aspects of the airport
performance and exhibited several deficiencies: (1) they were concerned with specific flows
or entities (e.g. aircraft, passengers, baggage), (2) they focused on specific airport elements
(e.g. runway system, apron, terminal), (3) they considered one (or very few) airport performance
indicator at a time (e.g. capacity, noise, safety, emissions), and (4) they were tailored for a
specific level of decision making, either strategic, tactical or operational. At the outset, there
was a clear lack of integrated modelling capabilities for assessing multiple performance
measures
simultaneously (and their trade-offs) for the airport system in its entirety (i.e. ‘total
airport’), that is, for both airport airside and landside simultaneously.
The latest developments in the airport modelling landscape involve the emergence of integrated
platforms or systems1. Currently, there are a limited number of software products/decision support
systems (mainly ‘off-the-shelf’) with integrated impact analysis capabilities for total airport
operations.
Most of them are purely simulation platforms basically integrating detailed simulation tools at a microscopic level. As a result, they do not exhibit macroscopic/aggregate analysis
capabilities
at the strategic decision making level with the use of analytical models. Furthermore,
the existing, simulation based tools are quite complicated, rather data intensive, have a costly set
up process for different airports, and require substantial tool familiarity
and prior computational
expertise. Another common feature for most of these tools is that they capture the airside-landside
interaction, but still provide limited trade-off analysis capabilities, since they primarily focus
on capacity and delay metrics. As a result, the basic modelling challenge remains, that is, to
develop systems and tools that will not only capture the manifold aspects of airport performance
in isolation, but will be also able to analyse, with reasonable effort, the various trade-offs and
interdependencies among these performance measures, entities, or airport elements.
In response to the identified modelling needs, an integrated Decision Support System (DSS),
the ‘Supporting Platform for Airport Decision Making and Efficiency Analysis’ (SPADE DSS),
has been developed recently. The proposed system has the form of a computational platform that
seamlessly integrates a variety of existing analytical models and simulation
tools in order to
capture the interdependencies among various measures of airport effectiveness (e.g. capacity,
delays, level of service, noise, safety, costs and benefits) and enable performance trade-off
analyses at various levels of detail (e.g. strategic, tactical/operational).
Furthermore, the SPADE
DSS allows decision makers and analysts to evaluate the efficiency of the entire airport complex
simultaneously (including also interaction effects among airport elements). However, the most
important and innovative element of the proposed
modelling approach is the adoption of the ‘use
case’ paradigm as the main building component
of the system implementation structure. The use
case driven implementation approach supports a problem or decision oriented approach that is
capable of addressing airport planning decisions in a user-friendly manner and at a reasonable
effort without requiring prior familiarity of the user with the selected tools (e.g. build
baseline/‘what-if’ scenarios, prepare and exchange data sets, perform trade-off analysis).
The objective of this chapter is twofold:
1. to introduce the structure and constituting elements of the SPADE system; and
2. to demonstrate the decision support capabilities of the system under ‘real-world’ conditions by
means of two manifestations of the system for strategic decision making (Athens International
Airport) and operational/tactical decision making (Amsterdam Airport Schiphol).
The remainder of this chapter consists of four main sections. Section 2.2 provides an overall
description of the high level structure of the SPADE DSS with special emphasis placed on the
use case driven modelling concept. Section 2.3 provides a demonstration of two application
instances of the system for strategic and operational/tactical decision making, respectively.
Section 2.4 presents the concluding remarks and lessons learnt during the system implementation,
whilst reporting some brief results from the evaluation of the system. Finally, the final
sections present the acknowledgements and a list of reference sources
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
A Set of Approximate and Compatible Models for Airport Strategic Planning on Airside and on Landside
No full textThe use of models as decision-support tools for the development of airport infrastructure
has been steadily growing. However, existing models still suffer from lack of integration
and from severe limitations in their flexibility and usability. In this paper we report on two
recently proposed models for airport strategic planning on airside and landside, and
discuss their integration. The models are macroscopic in nature, and provide estimates of
the capacity and performance of the airport quickly and with little effort. With the use of a
common database, these models can be integrated and share the same set of data. It is
then illustrated that in this way the, sometimes significant, interactions between airside
and landside operations can be captured
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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