AI and OR in management of operations: history and trends

The last decade has seen a considerable growth in the use of Artificial Intelligence (AI) for operations management with the aim of finding solutions to problems that are increasing in complexity and scale. This paper begins by setting the context for the survey through a historical perspective of OR and AI. An extensive survey of applications of AI techniques for operations management, covering a total of over 1200 papers published from 1995 to 2004 is then presented. The survey utilizes Elsevier's ScienceDirect database as a source. Hence, the survey may not cover all the relevant journals but includes a sufficiently wide range of publications to make it representative of the research in the field. The papers are categorized into four areas of operations management: (a) design, (b) scheduling, (c) process planning and control and (d) quality, maintenance and fault diagnosis. Each of the four areas is categorized in terms of the AI techniques used: genetic algorithms, case-based reasoning, knowledge-based systems, fuzzy logic and hybrid techniques. The trends over the last decade are identified, discussed with respect to expected trends and directions for future work suggested

Policy additionality for UK emissions trading projects: a report for the Department of Trade & Industry

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STREAM WATER QUALITY MANAGEMENT: A STOCHASTIC MIXED-INTEGER PROGRAMMING MODEL

Water quality management under the watershed approach of Total Maximum Daily Load (TMDL) programs requires that water quality standards be maintained throughout the year. The main purpose of this research was to develop a methodology that incorporates inter-temporal variations in stream conditions through statistical distributions of pollution loading variables. This was demonstrated through a cost minimization mixed-integer linear programming (MIP) model that maintains the spatial integrity of the watershed problem. Traditional approaches for addressing variability in stream conditions are unlikely to satisfy the assumptions on which these methodologies are founded or are inadequate in addressing the problem correctly when distributions are not normal. The MIP model solves for the location and the maximum capacity of treatment plants to be built throughout the watershed which will provide the optimal level of treatment throughout the year. The proposed methodology involves estimation of parameters of the distribution of pollution loading variables from simulated data and use of those parameters to re-generate a suitable number of random observations in the optimization process such that the new data preserve the same distribution parameters. The objective of the empirical model was to minimize costs for implementing pH TMDLs for a watershed by determining the level of treatment required to attain water quality standards under stochastic stream conditions. The output of the model was total minimum costs for treatment and selection of the spatial pattern of the least-cost technologies for treatment. To minimize costs, the model utilized a spatial network of streams in the watershed, which provides opportunities for cost-reduction through trading of pollution among sources and/or least-cost treatment. The results were used to estimate the costs attributable to inter-temporal variations and the costs of different settings for the margin of safety. The methodology was tested with water quality data for the Paint Creek watershed in West Virginia. The stochastic model included nine streams in the optimal solution. An estimate of inter-temporal variations in stream conditions was calculated by comparing total costs under the stochastic model and a deterministic version of the stochastic model estimated with mean values of the loading variables. It was observed that the deterministic model underestimates total treatment cost by about 45 percent relative to the 97th percentile stochastic model. Estimates of different margin of safety were calculated by comparing total costs for the 99.9th percentile treatment (instead of an idealistic absolute treatment) with that of the 95th to 99th percentile treatment. The differential costs represent the savings due to the knowledge of the statistical distribution of pollution and an explicit margin of safety. Results indicate that treatment costs are about 7 percent lower when the level of assurance is reduced from 99.9 to 99 percent and 21 percent lower when 95 percent assurance is selected. The application of the methodology, however, is not limited to the estimation of TMDL implementation costs. For example, it could be utilized to estimate costs of anti-degradation policies for water quality management and other watershed management issues.Resource /Energy Economics and Policy,

Sustainable seabed mining: guidelines and a new concept for Atlantis II Deep

The feasibility of exploiting seabed resources is subject to the engineering solutions, and economic prospects. Due to rising metal prices, predicted mineral scarcities and unequal allocations of resources in the world, vast research programmes on the exploration and exploitation of seabed minerals are presented in 1970s. Very few studies have been published after the 1980s, when predictions were not fulfilled. The attention grew back in the last decade with marine mineral mining being in research and commercial focus again and the first seabed mining license for massive sulphides being granted in Papua New Guinea’s Exclusive Economic Zone.Research on seabed exploitation and seabed mining is a complex transdisciplinary field that demands for further attention and development. Since the field links engineering, economics, environmental, legal and supply chain research, it demands for research from a systems point of view. This implies the application of a holistic sustainability framework of to analyse the feasibility of engineering systems. The research at hand aims to close this gap by developing such a framework and providing a review of seabed resources. Based on this review it identifies a significant potential for massive sulphides in inactive hydrothermal vents and sediments to solve global resource scarcities. The research aims to provide background on seabed exploitation and to apply a holistic systems engineering approach to develop general guidelines for sustainable seabed mining of polymetallic sulphides and a new concept and solutions for the Atlantis II Deep deposit in the Red Sea.The research methodology will start with acquiring a broader academic and industrial view on sustainable seabed mining through an online survey and expert interviews on seabed mining. In addition, the Nautilus Minerals case is reviewed for lessons learned and identification of challenges. Thereafter, a new concept for Atlantis II Deep is developed that based on a site specific assessment.The research undertaken in this study provides a new perspective regarding sustainable seabed mining. The main contributions of this research are the development of extensive guidelines for key issues in sustainable seabed mining as well as a new concept for seabed mining involving engineering systems, environmental risk mitigation, economic feasibility, logistics and legal aspects

The Effects of Aquatic Invasive Species on Property Values: Evidence from a Quasi-Random Experiment

The invasion of ecosystems by non-native species is widely considered to be a principal threat to global biological diversity, yet the social costs of invasive species are not well-understood. The purpose of this study is to estimate a hedonic model of lakeshore property values to quantify the effects of a common aquatic invasive species – Eurasian Watermilfoil – on property values across an extensive system of over 170 lakes in the northern forest region of Wisconsin. In addition to providing empirical evidence as to the potential benefits from reducing the spread of invasive species, this paper also develops a quasi-experimental methodology to identify the effects of changes in endogenous neighborhood amenities within the commonly estimated hedonic framework. In our application, a lake is more likely to be invaded with Milfoil if it is more popular with recreational boaters. Therefore, since lakes popular with recreational boaters are also likely to be popular with potential residents, and since many aspects of a lake’s amenities may be difficult to quantify, the likelihood of Milfoil invasions is endogenous in a hedonic price equation. Our identification strategy is based on a spatial difference-in-difference specification, and uses fixed effects to control for observed and unobserved neighborhood effects, while exploiting changes in the Milfoil status of several lakes during the time period of our data. Results indicate that lakes invaded with Milfoil experienced an average 13% decrease in land values after invasion. The Milfoil results are robust across linear and non-linear specifications.Land Economics/Use, Resource /Energy Economics and Policy,

The diffusion of externalities from foreign direct investment: theory ahead of measurement

In this paper a structural estimation framework is developed to assess whether inward foreign direct investment (FDI) generates technological externalities. The econometric model is implemented in an empirical investigation with data from Colombia’s Manufacturing Census. So far, evidence of new technological opportunities for host-country firms arising from the operations of multinational corporations (MNCs) has been rather scarce. This is due to serious limitations in the way in which spillovers have been measured. In particular, empirical research has focused almost exclusively on intra-industry externalities while no allowance has been made for inter-industry technological externalities. But, in theory, the optimal location and organizational strategies by a MNC are chosen to minimize the risk of losing profits due to the leakage of technical information to potential competitors. Therefore, the host-country firms within the MNC subsidiary’s sector will tend to experience limited technological gains ensuing FDI, whereas producers in other sectors may benefit, especially if the MNC outsources to local upstream suppliers. While FDI may substitute investment by domestic plants within the MNC subsidiary’s sector, it can complement investment in other sectors. Hence, spillovers from FDI should be primarily inter-industry and not intra-industry. This conjecture is corroborated by testing of the mutisectoral model of FDI spillover diffusion on Colombian manufacturing data. Furthermore, both generic knowhow spillovers and linkage externalities are sizable Keywords; generic technology, inter-industry spillovers, absorptive capacity JEL codes: F21, F23, F43, O41, O34

2001 Consultation of organic farming research priorities in the UK

The following reports a consultation of organic farming research priorities in the UK in 2001. The information was collated by Organic Centre Wales, Institute of Rural Studies, University of Wales, Aberystwyth on behalf of MAFF organic farming unit and UKROFS A total of 62 responses received, of which 24 from farmers, 12 from researchers and research organisations and 26 from organic producers and other farming organisations Information on ongoing research was derived from the MAFF 2001 organic farming research review, SERAD listing of organic farming projects and MAFF project OFO171, Review of current European research on organic farming