Bottomland hardwood stands of the Mid-South region of the United States are some of the most productive forests in the country. A large percentage of these stands are owned by nonindustrial private forest landowners, who have little information on which to base management decisions. These stands are, therefore, a largely unmanaged and under-utilized reserve of high quality hardwoods. To provide landowners with a decision-making tool for comparing management scenarios, a growth and yield study was initiated in 1981. One hundred and fifty permanent plots were installed in red oaksweetgum stands. The study has been remeasured three times over the past 35 years. New plots were added when losses occurred due to natural disasters or harvesting. Stand level (Iles 2008), log grade volume distribution (Banzhaf 2009), and diameter distribution (Howard 2011) models were developed as component models of the overall growth and yield system. This study completes the modeling effort by developing individual tree equations for percent annual diameter growth and survival. Equations were constructed using linear, non-linear, and logistic regression techniques. The best set of developed equations was selected based on biological consistency, joint behavior when inserted into the growth and yield computer model, and the performance of each plot’s predicted future yield when compared to its observed data at the next projection period. Final independent stand level variables for the two models included age, diameter at breast height, trees per acre, and average height of dominant trees. Percent diameter growth and survival equations exhibited high fit statistics and when coupled with the other equations in the computer model, produced estimates for trees per acre, basal area, arithmetic and quadratic mean diameters with low bias and root mean squared error. The resulting growth and yield simulator implemented in Microsoft Visual Basic® Editor within Microsoft Excel® enables forest professionals and landowners to make better management decisions for their red oak-sweetgum mixture bottomland hardwood stands by projecting current forest inventories into the future, predicting average yields, and evaluating and comparing forest management scenarios.

O trabalho proposto considerou o desenvolvimento de uma abordagem por autômatos celulares para modelagem de recursos minerais. De uma maneira geral, os autômatos celulares permitem a modelagem de sistemas e fenômenos levando em conta parâmetros de forma, dimensão, geometria, regras de evolução, regras de vizinhança e estado inicial. Para a aplicação dos autômatos celulares, foi desenvolvida uma ferramenta de software com apoio do Núcleo de Desenvolvimento de Software, do Departamento de Engenharia de Departamento de Sistemas Eletrônicos da Escola Politécnica da Universidade de São Paulo. A ferramenta de modelagem desenvolvida foi aplicada para modelar um banco de dados conhecido na mineração, que é o Walker Lake Dataset Isaaks e Srivastava (1989). Os resultados obtidos demonstraram que a abordagem por ACs tem potencial para a área de modelagem de recursos minerais, e indicaram a importância de definir uma metodologia específica para a seleção do método de interpolação mais adequado para cada conjunto de dados estudados. / This research project proposes a new approach for modeling geological resources using cellular automata. In general, cellular automata allow modeling systems taking into account parameters of shape, dimensions, evolution rules, neighboring rules and initial state of the cells. For the application of cellular automata in this project, a new tool has been developed in conjunction with the Software Development Group of the Department of Electronics of University of São Paulo. The modeling tool has been applied to model a popular dataset in mining which is the Waker Lake dataset (Isaaks e Srivastava,1989). The results showed that the approach has potential for ACs to the area of modeling of mineral resources and indicated the importance of defining an interpolation method most appropriate for evolutionary change of ACs for the dataset studied.

O trabalho proposto considerou o desenvolvimento de uma abordagem por autômatos celulares para modelagem de recursos minerais. De uma maneira geral, os autômatos celulares permitem a modelagem de sistemas e fenômenos levando em conta parâmetros de forma, dimensão, geometria, regras de evolução, regras de vizinhança e estado inicial. Para a aplicação dos autômatos celulares, foi desenvolvida uma ferramenta de software com apoio do Núcleo de Desenvolvimento de Software, do Departamento de Engenharia de Departamento de Sistemas Eletrônicos da Escola Politécnica da Universidade de São Paulo. A ferramenta de modelagem desenvolvida foi aplicada para modelar um banco de dados conhecido na mineração, que é o Walker Lake Dataset Isaaks e Srivastava (1989). Os resultados obtidos demonstraram que a abordagem por ACs tem potencial para a área de modelagem de recursos minerais, e indicaram a importância de definir uma metodologia específica para a seleção do método de interpolação mais adequado para cada conjunto de dados estudados. / This research project proposes a new approach for modeling geological resources using cellular automata. In general, cellular automata allow modeling systems taking into account parameters of shape, dimensions, evolution rules, neighboring rules and initial state of the cells. For the application of cellular automata in this project, a new tool has been developed in conjunction with the Software Development Group of the Department of Electronics of University of São Paulo. The modeling tool has been applied to model a popular dataset in mining which is the Waker Lake dataset (Isaaks e Srivastava,1989). The results showed that the approach has potential for ACs to the area of modeling of mineral resources and indicated the importance of defining an interpolation method most appropriate for evolutionary change of ACs for the dataset studied.

The Impala Platinum Mines are located in the western limb of the Bushveld Complex. The economic platinum mineralization which is currently being mined at Impala Platinum occurs in the Merensky and the Upper Group 2 (UG2) Reefs. These ore bearing horizons are stratigraphically located in the Upper Critical Zone of the Bushveld Complex. Due to the variable stratigraphic distance between the UG2 Chromitite Layer and the Merensky Reef, each of these reef horizons is influenced by different geological structural features. It has been observed on several shafts that there is no direct correlation between geological structures encountered on the Merensky Reef to that seen on the UG2 Reef horizon. This observation was prevalent during the geological structural evaluation of the two reef horizons in the No. 12 Shaft area. The Merensky Reef presented itself geologically more favorable to the UG2 Chromitite Layer in terms of structural complexities. Other positive factors included global supply and demand for the resultant metals and the encouraging metal price. There was nonetheless limited trial mining of the UG2 Reef within the No. 12 Shaft area. However, as a result of unfavorable market conditions at the time and complicated geological features which would result in very low extraction rates, it was decided to temporarily cease all mining operations related to the UG2 Reef horizon in this area. It has been strongly recommended in previous geological evaluation reports that the UG2 Chromitite Layer in the No. 12 Shaft area be appraised in significant detail in order to determine the possibility of economically exploiting this mineralized horizon. Due to the current favorable economic climate for platinum group metals, it was suggested by senior management that the UG2 Chromitite Layer be re – evaluated. This dissertation discusses some of the investigative research which was conducted during this re - assessment. The project work comprised research in the following aspects, exploratory drilling, interpretation of geological structural data, grade estimation, mineral resource estimation, financial and sensitivity analyses and aspects concerning risk management. Throughout the project all the input parameters and resultant calculations related to grade, mineral resource and reserve, financial and sensitivity analyses were based on tentative estimates which reflect the author’s personal opinions and assumptions. It is not absolute data of Impala Platinum and thus does not in any way reflect the views of the company. The UG2 Chromitite Layer in the No. 12 Shaft area was benchmarked against the neighboring shafts in terms of its geological and metallurgical characteristics. It was found that regionally, the UG2 Reef displays very limited variability. The financial assessment based on average market input data and assumptions have revealed positive results with regards to general financial and marketing decisions and strategies. In the risk assessment, the high impact risks generally facing all mining companies were found to be within manageable levels. From the investigative geological research based on general business decision criteria, market averages, estimations and assumptions which are used to broadly evaluate projects in the mining industry, it has been demonstrated that it would be economically viable to mine the UG2 Chromitite Layer in the No. 12 Shaft area of Impala Platinum. / Dissertation (MSc (Earth Science Practice and Management))--University of Pretoria, 2008. / Geology / unrestricted

This Master's thesis presents a method for on-line estimation of vehicle mass and road grade using Kalman filter. Many control strategies aiming for better fuel economy, drivability and safety in today's vehicles rely on precise vehicle operating information. In this context, vehicle mass and road grade are crucial parameters. The method is based on an extended Kalman filter (EKF) and a longitudinal vehicle model. The main advantage of this method is its applicability on drivelines with continuous power output during gear shifts and cost effectiveness compared to hardware solutions. The performance has been tested on both simulated data and on real measurement data, collected with a truck on road. Two estimators were developed; one estimates both vehicle mass and road grade and the other estimates only vehicle mass using an inclination sensor as an additional measurement. Tests of the former estimator demonstrate that a reliable mass estimate with less than 5 % error is often achievable within 5 minutes of driving. Furthermore, the root mean square error of the grade estimate is often within 0.5°. Tests of the latter estimator show that this is more accurate and robust than the former estimator with a mass error often within 2 %. A sensitivity analysis shows that the former estimator is fairly robust towards minor modelling errors. Also, an observability analysis shows under which circumstances simultaneous vehicle mass and road grade is possible.