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We assemble a dataset which enhances existing Central America and Mexico data for the NGASubduction (NGA-Sub) project, including now additional earthquake ground motions and site parameters from Mexico. This data has been used to provide regional customization of NGA-Sub global Ground Motion Models (GMMs) for application in Mexico, paying particular attention to the site response of Mexico City (CDMX). The expanded database for Mexico incorporates smaller magnitude earthquakes (M < 6) and three significant events (M 7.2-8.3) that occurred in 2017 and 2018. These latter events are particularly important, because they are well recorded over a broad distance range and apply for hazard-critical conditions. Our focus here is on presenting the observed site response in CDMX, which we model based on the time-averaged shear wave velocity in the upper 30 meters (VS30) and the Peak Ground Acceleration at a reference rock site (PGAr). The empirical model we propose is different from previous work in several ways. First, it is properly centered with respect to GMMs. Second, it is referenced to VS30 = 760 m/s, which is significantly firmer than the reference site previously used in practice, taken from a location on the UNAM campus with VS30 ~ 300 m/s. Third, we identify site amplification as nonlinear, whereas linear response has been assumed in prior models. The extent of this nonlinearity is characterized using an established seismic zonation for CDMX, being more pronounced in softer sites (Zone III) compared to stiffer ones (Zone I). This nonlinear effect is prominent at short periods and disappears at long periods. The advantages of the provided model include a unified framework for both within and outside CDMX (contrasting current practices) and the integration of applicable features from global models with necessary local customization.

The theory-practice gap (TPG) is well known in the environmental realm, referring to disconnects between knowledge generated through scientific research and the needs, expectations, and practices of knowledge users for environmental decision-making and practice. While the presence of the TPG is well established, we have yet to fully implement mechanisms for overcoming its challenges. Thus, our goal is to characterize the TPG and identify practical recommendations for minimizing it. Here, a diverse group of experts in the environmental realm (spanning landscape planning, conservation science, environmental sociology, resource management, political science, and anthropology, among others) present our perspectives on the TPG. More specifically, we share an organized framework for understanding the TPG and suggest recommendations that can help make progress in one or more dimension(s). Conceptual topics discussed are the implications of the gap and its persis-tence. Organizational/institutional topics include the implications of the overabundance, inaccessibility, and uncertainty of scientific information, and a need for mainstreaming boundary spanning activities. Lastly, cultural topics include differences in culture and epistemologies across knowledge generators and users, shifting cultures through co-production, and changes in educational curricula. Recommendations for minimizing the TPG include conceptually recasting what is considered ‘success,’ institutional reform, enhanced information delivery, leveraging knowledge brokers and boundary organizations, leveraging ‘champions’ in policy, using co-production and/or integrative research, confronting the contemporary ‘fake news’ phenomenon, and rethinking researcher and practitioner training and development. By sharing our framework and recom-mendations, we provide insight, as well as a starting point for those looking to narrow the TPG and improve knowledge generator-user relationships.

This paper presents a summary of lessons learned from implementing the ecosystem services (ES) approach into urban planning practice in different European urban settings. We summarise a survey co-created with, and presented to, researchers and end-users in city administrations from ten European case study cities. To complement the expert analysis, 14 semi-structured interviews were conducted among stakeholders to assess the use of ES in practice in urban settings. There was strong agreement between scientists and practitioners on both the opportunities and the barriers to uptake the ES concept in urban planning practice. Key agreements were that the ES concept supports decision-making as well as spatial planning, it is most useful as a communication tool, and monetarisation and public pressure can be considered as promoting factors. Barriers are lack of evidence including case studies, standardised methods and criteria to evaluate nature and its benefits, lack of legislations/reform, limited capacity and reluctance to apply ES in planning practice, and limited public involvement. On individual aspects, such as the monetarisation of ES, views differed both among the scientists and the practitioners. Derived from our investigations we summarize in which circumstances the ES concept is most relevant and useful for urban planners and decision-makers.

This paper presents a summary of lessons learned from implementing the ecosystem services (ES) approach into urban planning practice in different European urban settings. We summarise a survey co-created with, and presented to, researchers and end-users in city administrations from ten European case study cities. To complement the expert analysis, 14 semi-structured interviews were conducted among stakeholders to assess the use of ES in practice in urban settings. There was strong agreement between scientists and practitioners on both the opportunities and the barriers to uptake the ES concept in urban planning practice. Key agreements were that the ES concept supports decision-making as well as spatial planning, it is most useful as a communication tool, and monetarisation and public pressure can be considered as promoting factors. Barriers are lack of evidence including case studies, standardised methods and criteria to evaluate nature and its benefits, lack of legislations/reform, limited capacity and reluctance to apply ES in planning practice, and limited public involvement. On individual aspects, such as the monetarisation of ES, views differed both among the scientists and the practitioners. Derived from our investigations we summarize in which circumstances the ES concept is most relevant and useful for urban planners and decision-makers.

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Drill cores for the large Horse-Ivaal-Trukai copper-gold porphyry deposit at the Frieda River project (Papua New Guinea) were unusual due to a late stage gypsum-anhydrite stockwork event that overprinted much of the deposit. The gypsum and anhydrite leached out above the oxidised zone (effectively the water table) so that much of the rock above it is fragmented and gravel-like in texture while the rock below is uniform and competent. Large volumes of ore above the gypsum-anhydrite surface were expected to need minimal blasting and reduced comminution. It was thought this would have positive impacts on the operation, but the lack of standard geological logging methods available to define accurately the degree of in situ fragmentation led to difficulty in gaining certainty over the run-of-mine (ROM) product and grinding circuit feed size distributions. A method was developed which used image analysis techniques to take both the intact core and gravel into account to predict ROM fragmentation. Existing point-load test data was also used to infer the strength of the rock and its impact on blasting, crushing and grinding. This approach allowed development of ROM size distribution data and improved certainty in the results of comminution circuit designs., Drill cores for the large Horse-Ivaal-Trukai copper-gold porphyry deposit at the Frieda River project (Papua New Guinea) were unusual due to a late stage gypsum-anhydrite stockwork event that overprinted much of the deposit. The gypsum and anhydrite leached out above the oxidised zone (effectively the water table) so that much of the rock above it is fragmented and gravel-like in texture while the rock below is uniform and competent. Large volumes of ore above the gypsum-anhydrite surface were expected to need minimal blasting and reduced comminution. It was thought this would have positive impacts on the operation, but the lack of standard geological logging methods available to define accurately the degree of in situ fragmentation led to difficulty in gaining certainty over the run-of-mine (ROM) product and grinding circuit feed size distributions. A method was developed which used image analysis techniques to take both the intact core and gravel into account to predict ROM fragmentation. Existing point-load test data was also used to infer the strength of the rock and its impact on blasting, crushing and grinding. This approach allowed development of ROM size distribution data and improved certainty in the results of comminution circuit designs.

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This paper is a communication from the corresponding symposium at the Global Land Project Open Science Meeting, Berlin, March 2014. We explored the assumption that the ecosystem services-(ES) concept has the potential to support communication and collaboration between actors in land use planning. Iftrue, the concept could facilitate collaborative planning processes. We analyse how to evolve a planning context in which governance networks at the local landscape level gain importance in decision making, while the central government delegates power. From case studies presented during the symposium we learned that the ES-concept has been explored for application in local land use planning around the world. However, whether ES are recognizedas a useful planning concept depends on individual actor preferences and cultural and contextual factors, such as the actual nature-human relationship and gender differences. Also, successful application requires the support of novel assessment, design and visualization tools, which are designed to foster collaboration and social learning. The potential of the concept to contributeto collaborative relationships needs further investigation.

During the last few decades, land use changes have largely affected the global warming process through emissions of CO2. However, C sequestration in terrestrial ecosystems could contribute to the decrease of atmospheric CO2 rates. Although Mediterranean areas show a high potential for C sequestration, only a few studies have been carried out in these systems. In this study, we propose a methodology to assess the impact of land use and land cover change dynamics on soil organic C stocks at different depths. Soil C sequestration rates are provided for different land cover changes and soil types in Andalusia (southern Spain). Our research is based on the analysis of detailed soil databases containing data from 1357 soil profiles, the Soil Map of Andalusia and the Land Use and Land Cover Map of Andalusia. Land use and land cover changes between 1956 and 2007 implied soil organic C losses in all soil groups, resulting in a total loss of 16·8Tg (approximately 0·33Tg y-1). Afforestation increased soil organic C mostly in the topsoil, and forest contributed to sequestration of 8·62Mgha-1 of soil organic C (25·4 per cent). Deforestation processes implied important C losses, particularly in Cambisols, Luvisols and Vertisols. The information generated in this study will be a useful basis for designing management strategies for stabilizing the increasing atmospheric CO2 concentrations by preservation of C stocks and C sequestration.

The SmartTag ore tracking system was installed at the Kittila underground open stoping gold mine, Finland, in 2013. This system allows spatial ore characteristic data of a parcel of ore to be linked with time-based plant performance data such as particle size distribution, specific energy, and throughput. The orebody at Kittila is complex, and ore type can vary between each loader bucket which makes reconciliation and scheduling difficult. Environmental conditions can be extreme, with temperatures down to -20 degrees C. SmartTags in run-of-mine ore allow for monitoring of ore from underground loader through to the processing plant. When a tag is detected at the plant, the characteristics of its associated ore are compared to those expected in the plant, and changes can be made to processing options if necessary. When troublesome ore types are identified, plant feed with similar properties can be flagged as having the potential to disrupt plant throughput or recovery, and remedial action taken. Tags and analysis results are used daily at Kittila to evaluate and adjust mill feed based on gold and sulphur grades. Monthly results are used to reconcile the amount of mill feed from each stope, which can then be converted into a monetary value., The SmartTag ore tracking system was installed at the Kittila underground open stoping gold mine, Finland, in 2013. This system allows spatial ore characteristic data of a parcel of ore to be linked with time-based plant performance data such as particle size distribution, specific energy, and throughput. The orebody at Kittila is complex, and ore type can vary between each loader bucket which makes reconciliation and scheduling difficult. Environmental conditions can be extreme, with temperatures down to -20 degrees C. SmartTags in run-of-mine ore allow for monitoring of ore from underground loader through to the processing plant. When a tag is detected at the plant, the characteristics of its associated ore are compared to those expected in the plant, and changes can be made to processing options if necessary. When troublesome ore types are identified, plant feed with similar properties can be flagged as having the potential to disrupt plant throughput or recovery, and remedial action taken. Tags and analysis results are used daily at Kittila to evaluate and adjust mill feed based on gold and sulphur grades. Monthly results are used to reconcile the amount of mill feed from each stope, which can then be converted into a monetary value.

A Metso SmartEar was installed at the Pueblo Viejo Au operation in the Dominican Republic to monitor the acoustic emissions of the semiautogenous grinding mill and to optimise mill control. One output from the system is the impact counter, which measures steel-on-steel impacts on the mill shell and uses both frequency and time domain analysis to approximate the number of ball impacts per minute. Tuning of the filters and impact counter was carried out and the final set points were filter 1 between 1 000 and 3 000 Hz, filter 2 between 100 and 1 000 Hz and impact counter frequency range between 1 000 and 3 000 Hz. The effectiveness of the system was validated by analysing a data set and correlating the relationship between grinding efficiency in terms of specific energy and sound levels from the system. The results indicated that a moderate impact count or sound level will on average produce more efficient grinding than low or high impact counts or sound levels. Contrary to expectation, the relationship between speed and impact was not direct. The relationship showed that the feeds are higher when the impacts are in the middle bands, and lower impacts corresponded with higher power. Overall, a medium level of impacts results in more efficient grinding., A Metso SmartEar was installed at the Pueblo Viejo Au operation in the Dominican Republic to monitor the acoustic emissions of the semiautogenous grinding mill and to optimise mill control. One output from the system is the impact counter, which measures steel-on-steel impacts on the mill shell and uses both frequency and time domain analysis to approximate the number of ball impacts per minute. Tuning of the filters and impact counter was carried out and the final set points were filter 1 between 1 000 and 3 000 Hz, filter 2 between 100 and 1 000 Hz and impact counter frequency range between 1 000 and 3 000 Hz. The effectiveness of the system was validated by analysing a data set and correlating the relationship between grinding efficiency in terms of specific energy and sound levels from the system. The results indicated that a moderate impact count or sound level will on average produce more efficient grinding than low or high impact counts or sound levels. Contrary to expectation, the relationship between speed and impact was not direct. The relationship showed that the feeds are higher when the impacts are in the middle bands, and lower impacts corresponded with higher power. Overall, a medium level of impacts results in more efficient grinding.

The Phu Kam Cu-Au deposit in Laos is an extremely heterogeneous orebody with complex and variable mineralogical, geological and geotechnical properties which affect plant throughput and metallurgical performance. An increased proportion of highly competent ores is expected from future operations which has the potential to limit plant throughput. A throughput forecasting and optimisation project was conducted to evaluate how current throughput rates could be maintained over the life of mine. The project involved a review of current blasting, crushing and grinding processes and the development of a throughput prediction model based on geometallurgical modelling. The identification of opportunities for increasing throughout and improving overall comminution circuit performance when treating the most competent ore types was also included. A shorter term objective was to determine if and when secondary crushing or other process changes would be required in the shorter term. The throughput prediction model consists of integrated, site-specific models for drill and blasting, crushing and milling which were developed, calibrated and validated using SmartTag ore tracking technology, which links ore source and properties with blasting and plant performance in real time. A GeoMetso system is also being implemented which uses SmartTag to continuously collect plant data and automatically update the predictive models and block model in real time, eliminating the need for ore characterisation tests and improving the accuracy and predictive ability of the geometallurgical model., The Phu Kam Cu-Au deposit in Laos is an extremely heterogeneous orebody with complex and variable mineralogical, geological and geotechnical properties which affect plant throughput and metallurgical performance. An increased proportion of highly competent ores is expected from future operations which has the potential to limit plant throughput. A throughput forecasting and optimisation project was conducted to evaluate how current throughput rates could be maintained over the life of mine. The project involved a review of current blasting, crushing and grinding processes and the development of a throughput prediction model based on geometallurgical modelling. The identification of opportunities for increasing throughout and improving overall comminution circuit performance when treating the most competent ore types was also included. A shorter term objective was to determine if and when secondary crushing or other process changes would be required in the shorter term. The throughput prediction model consists of integrated, site-specific models for drill and blasting, crushing and milling which were developed, calibrated and validated using SmartTag ore tracking technology, which links ore source and properties with blasting and plant performance in real time. A GeoMetso system is also being implemented which uses SmartTag to continuously collect plant data and automatically update the predictive models and block model in real time, eliminating the need for ore characterisation tests and improving the accuracy and predictive ability of the geometallurgical model.

Soil C sequestration through changes in land use and management is one of the sustainable and long-term strategies to mitigate climate change. This research explores and quantifies the role of soil and land use as determinants of the ability of soils to store C along Mediterranean systems. Detailed studies of soil organic C (SOC) dynamics are necessary in order to identify factors determining fluctuations and intensity of changes. In this study, SOC contents from different soil and land use types have been investigated in Andalusia (Southern Spain). We have used soil information from different databases, as well as land use digital maps, climate databases and digital elevation models. The average SOC content for each soil control section (0-25, 25-50 and 50-75 cm) was determined and SOC stocks were calculated for each combination of soil and land use type, using soil and land cover maps. The total organic C stocks in soils of Andalusia is 415 Tg for the upper 75cm, with average values ranging from 15.9 Mg C ha-1 (Solonchaks under "arable land") to 107.6 Mg Cha-1 (Fluvisols from "wetlands"). Up to 55 % of SOC accumulates in the top 25 cm of soil (229.7 Tg). This research constitutes a preliminary assessment for modelling SOC stock under scenarios of land use and climate change. © Author(s) 2012. CC Attribution 3.0 License.

Blast-induced orebody movement can be measured using visual markers or remote markers such as magnetic or RFID, but it is difficult to model movement with a purely theoretical approach. Rock mass structure, blast energy, design and timing contours all have significant and interrelated effects on blast movement vectors. There have been significant advances in blast movement modelling capability, but unpredictable blast movement limits their use in the context of production ore control. Without physical field measurements, accurate predictions of movement are almost impossible. Limitations of traditional surface markers in determining three-dimensional (3D) blast movement within the orebody are reviewed, and advancements in accurately measuring these vectors within blasted ore discussed., Blast-induced orebody movement can be measured using visual markers or remote markers such as magnetic or RFID, but it is difficult to model movement with a purely theoretical approach. Rock mass structure, blast energy, design and timing contours all have significant and interrelated effects on blast movement vectors. There have been significant advances in blast movement modelling capability, but unpredictable blast movement limits their use in the context of production ore control. Without physical field measurements, accurate predictions of movement are almost impossible. Limitations of traditional surface markers in determining three-dimensional (3D) blast movement within the orebody are reviewed, and advancements in accurately measuring these vectors within blasted ore discussed.

Two systems are described that have been developed by Metso Minerals Process Technology for measuring mill load, the SmartEar acoustic system and an online model-based charge estimation system. SmartEar analyses an audio signal from the mill, allowing each different frequency component to be viewed, analysed and used in process control for load estimation. By isolating different frequencies, SmartEar can provide an estimate of mill load. The online dynamic mill model uses measurable mill parameters such as power to predict the current total load. Kalman filtering can also be used to further increase the accuracy of the model. Both systems have been installed at the Cannington Pb-Zn-Ag mine in Queensland, Australia, to measure the load within the autogenous grinding mill. The load estimations were compared with the bearing pressure reading, which is the current method used to control mill load. The redundant estimates of mill load provide increased confidence and more robust grinding operation under a wide range of conditions., Two systems are described that have been developed by Metso Minerals Process Technology for measuring mill load, the SmartEar acoustic system and an online model-based charge estimation system. SmartEar analyses an audio signal from the mill, allowing each different frequency component to be viewed, analysed and used in process control for load estimation. By isolating different frequencies, SmartEar can provide an estimate of mill load. The online dynamic mill model uses measurable mill parameters such as power to predict the current total load. Kalman filtering can also be used to further increase the accuracy of the model. Both systems have been installed at the Cannington Pb-Zn-Ag mine in Queensland, Australia, to measure the load within the autogenous grinding mill. The load estimations were compared with the bearing pressure reading, which is the current method used to control mill load. The redundant estimates of mill load provide increased confidence and more robust grinding operation under a wide range of conditions.

A description is given of the process integration and optimisation methodology developed by Metso Minerals Process Technology for optimising blasting and comminution processes in relation to fragmentation. The method involves a number of steps including benchmarking, rock characterisation, measurements, modelling/simulation of blasting and comminution processes and, where required, material tracking. The measurements collected at site are combined with rock characterisation and definition of ore domains to model the complete process chain. The data are used to develop site-specific models of blast fragmentation, crushing, grinding and flotation, allowing customised blast patterns to be developed to optimise crushing and grinding performance. Process constraints such as wall stability, ore dilution, muck pile characteristics, size of mining equipment, size and installed power of crushing and milling equipment and other process bottlenecks are considered. Case studies presented include investigation of relationship between powder factor and SAG mill throughput at a Cu mine, fragmentation measurement and modelling at a number of mine sites and the use of rock characterisation and blast domain definition to improve throughput forecasting., A description is given of the process integration and optimisation methodology developed by Metso Minerals Process Technology for optimising blasting and comminution processes in relation to fragmentation. The method involves a number of steps including benchmarking, rock characterisation, measurements, modelling/simulation of blasting and comminution processes and, where required, material tracking. The measurements collected at site are combined with rock characterisation and definition of ore domains to model the complete process chain. The data are used to develop site-specific models of blast fragmentation, crushing, grinding and flotation, allowing customised blast patterns to be developed to optimise crushing and grinding performance. Process constraints such as wall stability, ore dilution, muck pile characteristics, size of mining equipment, size and installed power of crushing and milling equipment and other process bottlenecks are considered. Case studies presented include investigation of relationship between powder factor and SAG mill throughput at a Cu mine, fragmentation measurement and modelling at a number of mine sites and the use of rock characterisation and blast domain definition to improve throughput forecasting.

The installation is described of an OCS expert system and three VisioRock online particle size analysis cameras to optimise the performance of the grinding circuit at the Cannington, Queensland, Ag-Pb operation. The main purpose of the system, which incorporates a dynamic SAG/AG mill model, was to stabilise grind size and feed to the flotation circuit. Online vision-based particle size measurements of the AG mill feed and recycle crusher product are integrated into the logic of the control algorithm. Significant stable throughput increases have been achieved, AG mill overload events have been reduced and pebble crusher utilisation has also increased., The installation is described of an OCS expert system and three VisioRock online particle size analysis cameras to optimise the performance of the grinding circuit at the Cannington, Queensland, Ag-Pb operation. The main purpose of the system, which incorporates a dynamic SAG/AG mill model, was to stabilise grind size and feed to the flotation circuit. Online vision-based particle size measurements of the AG mill feed and recycle crusher product are integrated into the logic of the control algorithm. Significant stable throughput increases have been achieved, AG mill overload events have been reduced and pebble crusher utilisation has also increased.

A description is given of the process integration and optimisation (PIO) method which has been developed by Metso Minerals Process Technology Asia-Pacific to improve the efficiency of the mine/mill interface. The methodology involves benchmarking, rock characterisation, measurements, modelling/simulation and, where required, material tracking. The rock characterisation step defines blasting domains and allows different blasting and crushing strategies to be developed. A list of operational and control changes are developed for both the mine and the concentrator. Simulation tools can also be used to compare current with recommended practices, so that when material properties vary over time the benefits can still be quantified. The success of a PIO project relies on the ability of an organisation to implement change, both operationally and culturally., A description is given of the process integration and optimisation (PIO) method which has been developed by Metso Minerals Process Technology Asia-Pacific to improve the efficiency of the mine/mill interface. The methodology involves benchmarking, rock characterisation, measurements, modelling/simulation and, where required, material tracking. The rock characterisation step defines blasting domains and allows different blasting and crushing strategies to be developed. A list of operational and control changes are developed for both the mine and the concentrator. Simulation tools can also be used to compare current with recommended practices, so that when material properties vary over time the benefits can still be quantified. The success of a PIO project relies on the ability of an organisation to implement change, both operationally and culturally.

Froth images were collected from various cells operated at different air rates and froth depths in the Northparkes, New South Wales, Cu roughing and scavenging circuit. Samples were also collected to determine the cell performance under each operating condition. The froth images were processed using the Visiofroth system and froth velocity, bubble size, froth collapse rate and froth colour parameters calculated. The parameters were compared to the measured concentrate flow and concentrate grade produced under each condition. The results showed that the grade of attached particles on the surface of the froth was linearly correlated with the bubble collapse rate. Overall concentrate grade was best predicted using an equation incorporating the collapse rate and velocity parameters. The concentrate tonnage flow is strongly correlated with froth velocity whereas the concentrate grade is best correlated using froth velocity in combination with a bubble stability parameter which affects the bubble size distribution on the top surface of the froth. The velocity measured by Visiofroth can be used to increase or decrease recovery to achieve a particular processing target, and may potentially be used in a process control optimisation strategy., Froth images were collected from various cells operated at different air rates and froth depths in the Northparkes, New South Wales, Cu roughing and scavenging circuit. Samples were also collected to determine the cell performance under each operating condition. The froth images were processed using the Visiofroth system and froth velocity, bubble size, froth collapse rate and froth colour parameters calculated. The parameters were compared to the measured concentrate flow and concentrate grade produced under each condition. The results showed that the grade of attached particles on the surface of the froth was linearly correlated with the bubble collapse rate. Overall concentrate grade was best predicted using an equation incorporating the collapse rate and velocity parameters. The concentrate tonnage flow is strongly correlated with froth velocity whereas the concentrate grade is best correlated using froth velocity in combination with a bubble stability parameter which affects the bubble size distribution on the top surface of the froth. The velocity measured by Visiofroth can be used to increase or decrease recovery to achieve a particular processing target, and may potentially be used in a process control optimisation strategy.

Metso Minerals Process Technology Asia-Pacific and South America (MMPT) have been working with operations around the world to increase their efficiency through Mine-to-Mill or Process Integration and Optimisation (PIO) projects. These projects have delivered significant improvements in mine efficiency, mill throughput and reduced operating costs at mines around the world. The MMPT methodology involves rock characterisation, site auditing, data collection, modelling/simulation and implementation of integrated operating and control strategies on site. After a site visit to collect data on geology, mining and processing, a typical PIO project builds a site-specific model of the various stages of the mine's operations. This proven methodology has applications ranging from greenfield projects to long-standing operations. The paper discusses a recent application of PIO conducted at a large open-pit operation in South America and emphasises that all operations have the potential to use their current equipment more efficiently., Metso Minerals Process Technology Asia-Pacific and South America (MMPT) have been working with operations around the world to increase their efficiency through Mine-to-Mill or Process Integration and Optimisation (PIO) projects. These projects have delivered significant improvements in mine efficiency, mill throughput and reduced operating costs at mines around the world. The MMPT methodology involves rock characterisation, site auditing, data collection, modelling/simulation and implementation of integrated operating and control strategies on site. After a site visit to collect data on geology, mining and processing, a typical PIO project builds a site-specific model of the various stages of the mine's operations. This proven methodology has applications ranging from greenfield projects to long-standing operations. The paper discusses a recent application of PIO conducted at a large open-pit operation in South America and emphasises that all operations have the potential to use their current equipment more efficiently.

A description is given of a constraint-based expert control system which has been implemented on the high-grade crushing and screening plant at Mount Tom Price, Western Australia, along with VisioRock, a vision- based oversize detection system operating on six product conveyor belts. The expert system control has resulted in increased production by maximising dynamic constraint utilisation. The latter is a concept developed for effectively evaluating constraint-based control logic performance. Details are given of the hardware and software used and the operational results., A description is given of a constraint-based expert control system which has been implemented on the high-grade crushing and screening plant at Mount Tom Price, Western Australia, along with VisioRock, a vision- based oversize detection system operating on six product conveyor belts. The expert system control has resulted in increased production by maximising dynamic constraint utilisation. The latter is a concept developed for effectively evaluating constraint-based control logic performance. Details are given of the hardware and software used and the operational results.

An ore characterisation and mine-to-mill throughput modelling approach at the 120 000 t/d Cu-Au plant in Indonesia has significantly improved prediction of mill throughput rates. Ore domains defined from ore lithology, rock structure designation and rock strength index are used in blasting, crushing and grinding models to provide accurate throughput predictions for mediium- to long-term production forecasting, although short-term predictions are indluenced by external factors such as segregation, surge-pile residence and blending. Benefits have included greatly improved mine-mill communication and optimum blast fragment generation and prediction., An ore characterisation and mine-to-mill throughput modelling approach at the 120 000 t/d Cu-Au plant in Indonesia has significantly improved prediction of mill throughput rates. Ore domains defined from ore lithology, rock structure designation and rock strength index are used in blasting, crushing and grinding models to provide accurate throughput predictions for mediium- to long-term production forecasting, although short-term predictions are indluenced by external factors such as segregation, surge-pile residence and blending. Benefits have included greatly improved mine-mill communication and optimum blast fragment generation and prediction.

A joint venture between the Porgera joint venture and Dyno Noble aimed at increasing throughput at the semi-autogenous (SAG) mills at the Porgera gold mine, in Papua New Guinea, through optimisation of the blast fragmentation. Test blasts showed that high-energy blasts could increase mill throughput by up to 15%. However changes in ore geology, potential ore dilution/loss and possible wall damage raised doubts about the economic benefits of using these blasts throughout the ore body. Dyno Noble's consulting arm, DynoConsult, and the Julius Kruttschnitt Mineral Research Centre (JKMRC) jointly developed a blast management system for tracking the quality of the blasts and the benefits in downstream processing. The implementation of the scheme is discussed, together with its results to date., A joint venture between the Porgera joint venture and Dyno Noble aimed at increasing throughput at the semi-autogenous (SAG) mills at the Porgera gold mine, in Papua New Guinea, through optimisation of the blast fragmentation. Test blasts showed that high-energy blasts could increase mill throughput by up to 15%. However changes in ore geology, potential ore dilution/loss and possible wall damage raised doubts about the economic benefits of using these blasts throughout the ore body. Dyno Noble's consulting arm, DynoConsult, and the Julius Kruttschnitt Mineral Research Centre (JKMRC) jointly developed a blast management system for tracking the quality of the blasts and the benefits in downstream processing. The implementation of the scheme is discussed, together with its results to date.

The Julius Kruttschnitt Mineral Research Centre's blast management system has been designed specifically for day-to-day use by mining engineers in conjunction with the JKSimBlast suite of blast design software tools. It allows the user to store data in a manner that facilitates its retrieval and archiving. By using the system over a period of time, a picture can be constructed of how certain parts of the rock mass behave when blasted in a particular manner and which blast configurations have been successful in achieving pre-defined outcomes. The storage of the information in database format allows querying to retrieve scenarios which meet certain criteria and the use of this information for further optimisation of the outcomes from a blast., The Julius Kruttschnitt Mineral Research Centre's blast management system has been designed specifically for day-to-day use by mining engineers in conjunction with the JKSimBlast suite of blast design software tools. It allows the user to store data in a manner that facilitates its retrieval and archiving. By using the system over a period of time, a picture can be constructed of how certain parts of the rock mass behave when blasted in a particular manner and which blast configurations have been successful in achieving pre-defined outcomes. The storage of the information in database format allows querying to retrieve scenarios which meet certain criteria and the use of this information for further optimisation of the outcomes from a blast.

A practical approach is presented to the design and assessment of blasts and it is shown how blasting operations can be engineered to solve classic blasting problems and to optimise blasting performance to meet the needs of excavation and downstream handling and beneficiation processes. The approach utilises the computer-based methodology and monitoring instrumentation developed by the JKMRC Blasting Group. Chapters are presented on mining issues and blasting performance, blast performance assessment, blast performance monitoring, computerised blast designs using a blast design editor, rock mass characterisation, explosive selection, fragmentation, near-field damage and wall control, muckpile properties and grade distribution and environmental impact of blasting., A practical approach is presented to the design and assessment of blasts and it is shown how blasting operations can be engineered to solve classic blasting problems and to optimise blasting performance to meet the needs of excavation and downstream handling and beneficiation processes. The approach utilises the computer-based methodology and monitoring instrumentation developed by the JKMRC Blasting Group. Chapters are presented on mining issues and blasting performance, blast performance assessment, blast performance monitoring, computerised blast designs using a blast design editor, rock mass characterisation, explosive selection, fragmentation, near-field damage and wall control, muckpile properties and grade distribution and environmental impact of blasting.

Bean golden mosaic geminivirus (BGMV) has a bipartite genome composed of two circular ssDNA components (DNA-A and DNA-B) and is transmitted by the whitefly, Bemisia tabaci. DNA-A encodes the viral replication proteins and the coat protein. To determine the role of BGMV coat protein systemic infection and whitefly transmission, two deletions and a restriction fragment inversion were introduced into the BGMV coat protein gene. All three coat protein mutants produced systemic infections when coinoculated with DNA-B onto Phaseolus vulgaris using electric discharge particle acceleration "particle gun." However, they were not sap transmissible and coat protein was not detected in mutant-infected plants. In addition, none of the mutants were transmitted by whiteflies. With all three mutants, ssDNA accumulation of DNA-A and DNA-B was reduced 25- to 50-fold and 3- to 10-fold, respectively, as compared to that of wild-type DNA. No effect on dsDNA-A accumulation was detected and there was 2- to 5-fold increase in dsDNA-B accumulation. Recombinants between the mutated DNA-A and DNA-B forms were identified when the inoculated coat protein mutant was linearized in the common region.

MultiVib is a far field vibration monitor which provides a cost effective means of obtaining blast vibration data from several locations at the same time. The use of an array of these units is much cheaper and more practical than using an expensive multi-channel data recorder. Using the MultiVib system, each monitor is initialised via a host computer and then taken to the monitoring site where it records the blast induced vibrations in solid state memory. After the blast the monitors are returned to the host computer for data retrieval and analysis. The system has recently been installed at the Jwaneng open cut diamond mine in Botswana to gather data for the study of the relationship of blast design to induced vibrations in the pit slopes. Preliminary results show that the MultiVib units are performing well., MultiVib is a far field vibration monitor which provides a cost effective means of obtaining blast vibration data from several locations at the same time. The use of an array of these units is much cheaper and more practical than using an expensive multi-channel data recorder. Using the MultiVib system, each monitor is initialised via a host computer and then taken to the monitoring site where it records the blast induced vibrations in solid state memory. After the blast the monitors are returned to the host computer for data retrieval and analysis. The system has recently been installed at the Jwaneng open cut diamond mine in Botswana to gather data for the study of the relationship of blast design to induced vibrations in the pit slopes. Preliminary results show that the MultiVib units are performing well.

In underground mining, unpredictable variability in ground conditions may result in suboptimal drilling and blasting patterns and poor performance. A system is needed that can help engineers organise and apply data and operating experience of geotechnical conditions, blasthole geometry, explosives, initiation and priming systems, initiation sequence, delay timing and overall results such as fragmentation, rock movement, overbreak and damage. The Julius Kruttschnitt Mineral Research Centre has been developing such a system. It is a hybrid of an information management software module called BMS (Blast Management System) and two design and analysis modules: 2DRing for underground production blasting and 2DFace for development blasting activities. The system captures drilling and blasting experience through the use of databases, and applies simple modelling and blast simulation to allow iterative improvement of the drill and blast design cycle., In underground mining, unpredictable variability in ground conditions may result in suboptimal drilling and blasting patterns and poor performance. A system is needed that can help engineers organise and apply data and operating experience of geotechnical conditions, blasthole geometry, explosives, initiation and priming systems, initiation sequence, delay timing and overall results such as fragmentation, rock movement, overbreak and damage. The Julius Kruttschnitt Mineral Research Centre has been developing such a system. It is a hybrid of an information management software module called BMS (Blast Management System) and two design and analysis modules: 2DRing for underground production blasting and 2DFace for development blasting activities. The system captures drilling and blasting experience through the use of databases, and applies simple modelling and blast simulation to allow iterative improvement of the drill and blast design cycle.

Metso Minerals Process Technology Asia Pacific uses hardened radio- frequency identification tags to track ores from blasting to downstream processes, thus ensuring that the spatial origin of the material is accurately known at all times and that important ore properties such as fragmentation, hardness, colour, texture, mineralogy or grade are tracked. RFID tags also allow operational parameters such as ore dilution, stockpile residence time and segregation to be estimated and metallurgical performance related to pit location for geometallurgical modelling. A RFID system consists of two parts: a tag or small microchip with a local coil antenna, and a reader with a larger antenna. Passive tags, detectable at 1.2 m, use the radiated energy from the reader antenna to power up the RFID chips, whereas longer-range active tags are equipped with small batteries. The tags, in their 50 mm hardened shells or in cases of varying sizes if segregation is being tracked, are inserted in the stemming of the blastholes and/or placed on the surface of the subsequent muckpile. Readers and antennae are installed over or under conveyor belts after the primary crusher and before the SAG mills. At a large South American copper mine with multiple ore sources feeding the mill, tag detection times were matched to excavator GPS data to quantify ore movement and dilution during the blast. The tags also indicated the arrival of ore from a trial blast at the crusher and SAG mills, so that sudden increases in throughput could be correlated to areas of high blast energy and blast design optimised., Metso Minerals Process Technology Asia Pacific uses hardened radio- frequency identification tags to track ores from blasting to downstream processes, thus ensuring that the spatial origin of the material is accurately known at all times and that important ore properties such as fragmentation, hardness, colour, texture, mineralogy or grade are tracked. RFID tags also allow operational parameters such as ore dilution, stockpile residence time and segregation to be estimated and metallurgical performance related to pit location for geometallurgical modelling. A RFID system consists of two parts: a tag or small microchip with a local coil antenna, and a reader with a larger antenna. Passive tags, detectable at 1.2 m, use the radiated energy from the reader antenna to power up the RFID chips, whereas longer-range active tags are equipped with small batteries. The tags, in their 50 mm hardened shells or in cases of varying sizes if segregation is being tracked, are inserted in the stemming of the blastholes and/or placed on the surface of the subsequent muckpile. Readers and antennae are installed over or under conveyor belts after the primary crusher and before the SAG mills. At a large South American copper mine with multiple ore sources feeding the mill, tag detection times were matched to excavator GPS data to quantify ore movement and dilution during the blast. The tags also indicated the arrival of ore from a trial blast at the crusher and SAG mills, so that sudden increases in throughput could be correlated to areas of high blast energy and blast design optimised.