21 research outputs found
An Interactive Multi-Criteria Decision Model for Reservoir Management: The Shellmouth Reservoir Case
Reservoir management is inherently multi-criterial, since any release decision involves implicit trade-offs between various conflicting objectives. The release decision reflects concerns such as flood protection, hydroelectric power generation, dilution of downstream wastewater and heat effluents, downstream municipal, agricultural and industrial water supply, environmental standards and recreational needs. This paper presents a framework for analysing trade-offs between several decision criteria, and includes the management of heated effluents from downstream thermoelectric power generation in an optimisation model for reservoir management. The model is formulated and analysed in an interactive multi-criteria decision making (MCDM) modelling framework. Rather than providing specific target levels or ad hoc constants in a Goal Programming framework, as proposed elsewhere, our multi-criteria framework suggests a systematic way of evaluating trade-offs by progressive preference assessment. The MCDM model, based on a Tchebycheff metric and a contracted cone approach, is learning-oriented and permits a natural exploration of the decision space while maintaining non-dominated decisions. A detailed case study of the Shellmouth Reservoir in Manitoba, Canada, serves as an illustration of the model
Interactive Multi-Criteria Decision Making in Production Economics
Decisions regarding Production Economics usually involve multiple objectives, such as minimisation of cost, resources, inactive time or maximisation of product quality, utilisation of fixed resources and customer service. Neglect of this problem characteristic may lead to ad hoc policies and inefficient decision-making. By advancing theory and applications, this dissertation strongly supports the concept of multi-criteria decision making (MCDM) for applied industrial decisions in planning and operation. The common theme is interactive MCDM, which is argued as closer to human decision-making and, in this context, claimed to be methodologically superior to methods based on preference assessment. Of the two parts in the dissertation, the first being theoretically oriented includes the compilation, description and investigation of an interactive method, IDEM, quantitatively characterising the method in terms of completeness and constructiveness. The MCDM methodology is extended with a characterisation and formalisation of a new conflict-based redundancy concept. The applied part of the dissertation focuses at decisions of frequent managerial interest: engineering design, planning of complex dynamic rptems and operational production planning. The strength of MCDM for Production Planning is illustrated by revisiting a classical inventory model and proposing an interactive MCDM model with computational and behavioural advantages. The work devoted to engineering design and concurrent engineering describe a formalisation of the decision process close to observed practice, but with decision support for variant design and interaction between functional areas. IDEM is used as a backbone in a decision model with outlined connections to tools as CAD, CAE and CAM. The design and analysis of prohibitively complex dynamic systems have so far primarily been subject to simulation techniques. Contributions are made to this area in terms of an interactive structured methodology, hybrid between MCDM and simulation. The underlying idea is to enable the decision-maker to work in criterion space and interactively explore the complex system. The practical usefulness of the interactive methodology is demonstrated in the final paper on multi-criteria decision modelling in reservoir management, applied to thermoelectric power generation. The release decision for a reservoir with downstream thermoelectric power plants is modelled and exemplified with the case of the Shellmouth Reservoir in Manitoba, Canada. The MCDM approach used in this context is the Interactive Weighted Tchebycheff Procedure in combination with decision maker-supplied bounds and enhanced communication
A strategy‑based framework for supplier selection: a grey PCA‑DEA approach
The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.Supplier selection is one of the key competencies in the sourcing function. Considering
the important role of suppliers in the strategy framework of supply chains, it is
surprising that the sourcing function has not been subject to more focused research
on the development of adequate decision support tools. The relatively simplified
ranking systems that often have been presented on an ad hoc basis offer only partial
information on the decision. This research attempts to develop a unified and integrated
structure for supplier selection practices across a supply chain on the basis
of strategic planning. Our evaluation is conducted by means of a multi-attribute
efficiency analysis models and a multivariate statistical method, a so-called principal
component analysis-data envelopment analysis (PCA-DEA) approach, to support
supplier relationship management under uncertainty. The main contribution of
this paper is to address the gap in the supply chain management (SCM) literature by
proposing a strategy-based method for supplier selection problems when data are
interrelated and interdependent. The proposed method in this study is applied to a
real-world case study in agri-food industry to demonstrate the advantages and applicability
of the proposed framework
Conflict, Harmony, and Independence: Relationships in Evolutionary Multi-criterion Optimisation
New <sup>10</sup>Be cosmogenic ages from the Vimmerby moraine confirm the timing of Scandinavian ice sheet deglaciation in southern Sweden
The overall pattern of deglaciation of the southern part of the Scandinavian Ice Sheet has been considered established, although details of the chronology and ice sheet dynamics are less well known. Even less is known for the south Swedish Upland because the area was deglaciated mostly by stagnation. Within this area lies the conspicuous Vimmerby moraine, for which we have used the terrestrial cosmogenic nuclide (<sup>10</sup>Be) exposure dating technique to derive the exposure age of six glacially transported boulders. The six <sup>10</sup>Be cosmogenic ages are internally consistent, ranging from 14.9 ± 1.5 to 12.4 ± 1.3 ka with a mean of 13.6 ±0.9 ka. Adjusting for the effects of surface erosion, snow burial and glacio-isostatic rebound causes the mean age to increase only by c. 6% to c. 14.4± 0.9 ka. The <sup>10</sup>Be derived age for the Vimmerby moraine is in agreement with previous estimates forthe timing of deglaciation based on radiocarbon dating and varve chronology. This result shows promise for further terrestrial cosmogenic nuclide exposure studies in southern Sweden