The quest for creating more reliable evidential maps with elevated prediction accuracy and minimal uncertainty remains a formidable challenge in mineral prospectivity mapping (MPM), particularly in the case of covered...
详细信息
The quest for creating more reliable evidential maps with elevated prediction accuracy and minimal uncertainty remains a formidable challenge in mineral prospectivity mapping (MPM), particularly in the case of covered or concealed deposits. This study introduces a multistage algorithm to generate a predictive porphyry intrusion evidential map using magnetic data. Rooted in the formation model of porphyry copper deposits (PCDs), the algorithm encompasses several key steps: (1) initiating with a radial symmetry transformation to detect circular geological features (i.e., porphyry intrusions), (2) none-minimum suppression of circularity responses and thresholding to identify the center of these features, (3) amplitude contrast transformation to highlight the extent of the features, and finally (4) employing the active contour algorithm to determine the size and geometry of probable porphyry targets. Implemented on aeromagnetic data from the Pariz region in southeastern Iran, the results were evaluated by location of previously known PCDs and 3D Cu isoshells derived from exploratory boreholes. Remarkably, all six known deposits in the area were identified, alongside the discovery of a new porphyry copper deposit, boasting 2847 MT with a copper grade of 0.42 %. Additionally, five new prospective targets that may serve as fertile environments for porphyry mineralization were proposed for further exploration. The results demonstrated that the proposed algorithm significantly enhances MPM of PCDs by effectively narrowing the exploration search space, delineating 20 % (126 of 629 km2) of the study area as prospective targets. Furthermore, the findings indicate that the magnetic signatures of PCDs on the generated map are notably sharper than those on the original reduction to pole map, affirming the algorithm's efficacy in delineating buried porphyry copper deposits.
A comprehensive dynamic model of a steam power plant, including turbine, governor, and boiler models, is proposed in this paper. The whole turbine-boiler control strategies inter alia turbine following, boiler followi...
详细信息
A comprehensive dynamic model of a steam power plant, including turbine, governor, and boiler models, is proposed in this paper. The whole turbine-boiler control strategies inter alia turbine following, boiler following, coordinated control, and sliding pressure control modes are also taken into account in the modelling procedure, making the integrated model adaptable for all the steam units. A novel multi-stage algorithm is asserted in the other part of the paper to estimate the obtained model parameters using input-output data from operational tests. Regarding the fact that the mechanical power as the turbine output and one of the synchronous generator (SG) inputs cannot be measured directly, an efficacious unknown input reconstruction (UIR) method is employed in this paper to determine the mechanical power from SG measured signals. The UIR observer in this method is obtained by solving a linear matrix inequality (LMI). Other parameters are identified by applying a Genetic algorithm (GA) to the measurement data. Finally, the acquired model and parameters are validated by employing the recorded data from several tests, and the results are discussed.
The paper analyses the problem of the convergence investigation for typical GMDH criteria based on the data sample division into two subsamples. This study is significant for additional justification of applying the G...
详细信息
We propose an RNS arithmetic-based FH pattern design approach that is well suited and easy to implement for practical OFDMA systems. The proposed FH scheme guarantees orthogonality among intracell users while randomiz...
详细信息
We propose an RNS arithmetic-based FH pattern design approach that is well suited and easy to implement for practical OFDMA systems. The proposed FH scheme guarantees orthogonality among intracell users while randomizing the intercell interferences and providing frequency diversity gains. We present detailed construction procedures and performance analysis for both independent and cluster hopping scenarios. Using simulation results, we demonstrate the gains due to frequency diversity and intercell interference diversity on the system bit error rate (BER) performance. Furthermore, the BER performance gain is consistent across all cells unlike other FH pattern design schemes such as the Latin squares (LSs-)-based FH pattern design where wide performance variations are observed across cells. Copyright (C) 2009 D. Zhu and B. Natarajan.
A multistage algorithm is presented to allow for the convenient and accurate computation of the finite amplitude-distorted acoustic fields produced by phased arrays and nonplanar sources. The algorithm also allows for...
详细信息
A multistage algorithm is presented to allow for the convenient and accurate computation of the finite amplitude-distorted acoustic fields produced by phased arrays and nonplanar sources. The algorithm also allows for non-normal (angled) beam computations.
The standard approach to the motion and structure estimation problem consists of two stages: (I) using the eight-point algorithm to estimate the nine essential parameters defined up to a scale factor and (2) refining ...
详细信息
The standard approach to the motion and structure estimation problem consists of two stages: (I) using the eight-point algorithm to estimate the nine essential parameters defined up to a scale factor and (2) refining the motion estimation based on some statistically optimal criteria, which is a nonlinear estimation problem on a five-dimensional space. Unfortunately, the results obtained are often not satisfactory. The problem is that the second stage is very sensitive to the initial guess and that it is very difficult to obtain a precise initial estimate from the first stage. This is because one performs a projection of a set of quantities that are estimated in a space of eight dimensions (by neglecting the constraints on the essential parameters), a much higher dimension than that of the real space, which is live dimensional. A novel approach is proposed by the introduction of an intermediate stage, which consists in estimating a 3 x 3 matrix defined up to a scale factor by imposing the rank-2 constraint (the matrix has seven independent parameters and is known as the fundamental matrix). The idea is to project parameters estimated in a high-dimensional space gradually onto a slightly lower-dimensional space, namely, from eight dimensions to seven and finally to five. The proposed approach has been tested with synthetic and real data, and a considerable improvement has been observed, The conjecture is that the imposition of the constraints arising from projective geometry should be used as an intermediate step to obtain reliable three-dimensional Euclidean motion and structure estimation from multiple calibrated images. The software is available on the Internet. (C) 1997 Optical Society of America.
An automatic, multistage algorithm for detecting minefields is introduced. This algorithm was tested, with encouraging results, against buried metal mines. The measurement data for this test were obtained using a low-...
详细信息
ISBN:
(纸本)0819418528
An automatic, multistage algorithm for detecting minefields is introduced. This algorithm was tested, with encouraging results, against buried metal mines. The measurement data for this test were obtained using a low-frequency airborne SAR, collected during an extensive ground penetration experiment in Yuma, Arizona, in June 1993. Although verified using SAR data, the automatic minefield detection technique may prove applicable to other remote sensors as well.
暂无评论