49results about How to "Build accurately" patented technology

The invention discloses a vehicle target motion state estimation method based on an unmanned aerial vehicle video, and relates to the technical field of computer vision and intelligent monitoring, and the method comprises the steps: receiving a real-time video stream of an unmanned aerial vehicle, decoding the real-time video stream to obtain an original video frame, carrying out the graying, zooming and normalization preprocessing to obtain a processed image, and synchronously adjusting the size of a vehicle bounding box; vehicle targets are detected, a unique ID is allocated for multi-target tracking, and a motion trail is maintained; determining a background feature region, detecting and tracking feature points to estimate an inter-frame transformation matrix, and performing accumulative transformation to obtain a background overall transformation relation and a historical frame-to-current frame mapping mechanism; calculating a displacement residual error based on the trajectory and the mapping, judging direction consistency, estimating a smooth speed, and updating a motion confidence coefficient to judge a vehicle motion or static state and static duration; outputting the ID, the state, the static duration and the average speed of the vehicle; the method effectively eliminates the motion interference of the unmanned aerial vehicle, improves the estimation precision, is suitable for the traffic monitoring of the unmanned aerial vehicle, and is high in real-time performance and reliability.

The invention provides a multi-physics field joint inversion method and device in geothermal exploration. The method comprises the following steps: acquiring seismic data, electromagnetic data and logging data in geothermal exploration; determining a loss function of the multi-physics field joint inversion network according to well point constraint loss, earthquake constraint loss and electromagnetic constraint loss in geothermal exploration and gradient consistency loss of the multi-physics field joint inversion network; according to the loss function of the multi-physics-field joint inversion network and seismic data, electromagnetic data and logging data in geothermal exploration, constructing the multi-physics-field joint inversion network; according to the method, the multi-physics field joint inversion network can be accurately constructed, the problems that traditional electromagnetic seismic joint inversion excessively depends on rock physical relation or physical property structure consistency assumption, and implementation conditions are harsh are solved, and a data basis can be provided for geothermal exploration.

The invention provides a road topological graph generation method and device, a vehicle and a storage medium, and relates to the technical field of automatic driving. The method comprises the following steps: acquiring a historical driving track of a vehicle in a target area, intersection position information in the target area and boundary information; according to the historical driving track and the boundary information, determining a passable area boundary of a road through which the historical driving track passes; according to the passable area boundary and the historical driving track, determining a road center line of a road through which the historical driving track passes; and based on the intersection position information, updating the road center line to generate a road topological graph. Therefore, the road topological graph of the target area can be accurately constructed based on the historical driving track, and the road topological graph comprises the connection relationship between the intersection and the road and the connection relationship between the roads, so that path planning from any starting point to terminal point in the target area can be realized, and the flexibility and success rate of valet parking are improved.

This invention relates to the field of lawn maintenance technology, and discloses a fusion perception method, device, equipment, and medium suitable for autonomous mobile devices. By introducing dynamic inverse perspective transformation assisted by lidar, it achieves a visual image projected onto a three-dimensional real terrain. Combined with deep fusion of visual and lidar data, it generates a high-precision, semantically rich three-dimensional environment model. This model can effectively reflect the terrain undulations and obstacle distribution in complex lawn environments, achieving multimodal perception with good environmental adaptability and high real-time performance on a low-cost hardware platform, supporting accurate and safe navigation and efficient task execution for the autonomous mobile device. It breaks the strong assumption of an absolutely flat ground surface, utilizing real-time lidar data to construct a non-planar ground model, achieving deep fusion of visual and lidar information, thereby improving perception accuracy and robustness with low-cost hardware configuration.

The application discloses a kind of Pt nanoparticle load Fe-based MOF photocatalyst and its preparation method and application, belong to environmental energy technical field.The preparation method disclosed in the application uses 2-amino terephthalic acid, FeCl3·6H2O and aqueous solution of chloroplatinic acid hexahydrate as raw material, through hydrothermal reaction, Pt nanoparticle is dispersed in situ and loaded NH2-MIL-101 (Fe), reduces interface charge transfer resistance, inhibits the recombination of photo-generated carriers, to further improve the photocatalytic nitrogen fixation activity, using the synergistic effect of NH2-MIL-101 (Fe) composite photocatalyst containing Pt nanoparticle to achieve the purpose of improving the yield of photocatalytic conversion of nitrogen to ammonia, significantly solve the high energy consumption and environmental pollution problem of traditional industrial nitrogen fixation Haber-Bosch method.

The invention relates to the technical field of visual SLAM positioning and mapping, and discloses a visual map data processing method and device, computer equipment and a storage medium. Firstly, panoramic semantic segmentation is carried out on an original image, a panoramic segmented image is generated, the panoramic segmented image comprises semantic information of each pixel, and the semantic information comprises prior dynamic semantic information. And performing optical flow estimation processing on the original image to obtain an optical flow image. Then, based on the panoramic segmented image, the optical flow image and the original image, feature points of a dynamic area are removed in real time, and a static feature image with higher precision is obtained; and finally, under the condition of performing motion tracking based on the static feature image and determining that the static feature image is a key frame, generating a dense point cloud map endowed with semantic information based on the original image, the static feature image and the panoramic segmentation image, and removing a point cloud with prior dynamic semantic information from the dense point cloud map. And a more accurate static environment map is constructed to update the point cloud map.

The application relates to the field of electronic technology and discloses a sonar three-dimensional imaging reconstruction method, device and equipment for the underwater environment of an inspection well, which projects sonar ring scanning data corresponding to each depth to a target plane based on target posture data of each depth to obtain first sonar ring scanning data corresponding to each depth; calculates first centroid position coordinates corresponding to each depth based on the first sonar ring scanning data of each depth, and calculates second centroid position coordinates corresponding to each depth based on reference sonar ring scanning data; determines a translation vector corresponding to each depth based on the first centroid position coordinates and the second centroid position coordinates of each depth; corrects the first sonar ring scanning data by using the translation vector of each depth to obtain target sonar ring scanning data corresponding to each depth; and determines an underwater three-dimensional model of the inspection well based on the target sonar ring scanning data of each depth, pixel quantity information, pixel spacing information and target posture data, so that the complex geometric shape of the whole inside of the inspection well can be restored completely and with high precision.

The utility model discloses an inspection robot high-precision stereoscopic visual perception system which comprises a shell, a data analysis and processing device is installed in the shell, an induction radar, a depth camera and a pan-tilt camera are arranged on the shell, and the relative positions of the induction radar, the depth camera and the pan-tilt camera are kept unchanged. The induction radar and the depth camera are arranged in front of the shell and used for detecting objects in front of the inspection robot and generating images to guide the inspection robot to move, the pan-tilt camera is arranged at the top of the shell and used for collecting reading information of an instrument panel, and the induction radar, the depth camera and the pan-tilt camera are connected with the data analysis and processing device. The sensing radar and the depth camera are used for collecting data for real-time processing and analysis, a three-dimensional space map can be rapidly constructed, the inspection robot can flexibly avoid various obstacles and efficiently and safely shuttle among all devices, and therefore the cloud deck camera is used for collecting reading information of an instrument panel, and the inspection efficiency is improved. And the inspection task is automatically and efficiently completed.

This application relates to a method, apparatus, and measurement system for dynamic measurement of assembly data. The measurement system includes a moving crossbeam and multiple calibration targets, with a 3D scanner and a laser tracker mounted on the moving crossbeam. The method includes: controlling the moving crossbeam to move to a measurement pose; positioning multiple calibration targets using the laser tracker to construct a geodetic coordinate system and tracking and determining the real-time pose of the 3D scanner in the geodetic coordinate system; controlling the 3D scanner to move and scan to obtain reference point cloud data and key area point cloud data of the assembly workpiece, and establishing the point cloud correlation between the two, establishing a workpiece coordinate system based on the reference point cloud data; based on the workpiece coordinate system, real-time pose, and point cloud correlation, mapping the key area point cloud data to the geodetic coordinate system and performing error correction; and generating an assembly deviation map based on the deviation between the corrected actual measurement data and the expected measurement data. This method can improve the cycle time efficiency and assembly accuracy pass rate of a pulsed assembly production line.

The invention belongs to the technical field of constructional engineering, and particularly relates to a Revit-based fabricated component family library construction and use method, which comprises the following steps: dividing a component family library into twelve system categories of three major majors of building, structure and electromechanical, standardizing naming and coding principles of corresponding component families, and gathering the component families in a table form; parameter elements and parameter categories of the component families are specified, the same parameters of the same component families are controlled by'type parameters', individual differences of the component families are controlled by'instance parameters', and the component families of different system categories are associated with one another by'global parameters', so that linkage between models is constructed; and performing encryption processing on the component family storage to protect the intangible digital assets. According to the invention, informatization, standardization and systematization management of components and parts are realized, the whole industry chain service of the building is supported, basic support is provided for application of the BIM model, and the current situation barrier of the industry is broken.

The invention discloses a multi-coal-source coal blending data processing method based on a WSMOTE algorithm, and belongs to the technical field of coal processing data processing, and the method comprises the steps: data collection and classification: collecting multi-dimensional data of a raw coal floating and sinking test, a coal blending test and the like, carrying out the preprocessing, dividing the data into a missing data set and a complete data set, carrying out the interpolation optimization of a missing value, and carrying out the calculation of the complete data set. And carrying out adaptive processing according to data distribution types, or carrying out weighted combination normalization according to feature importance, analyzing the number and distribution characteristics of minority class samples, dynamically adjusting the neighbor sample size and the new sample synthesis amount, and completing data enhancement and standardization. According to the method, standardized parameters are dynamically adjusted to adapt to data distribution changes, abnormal values are accurately processed, the combined interpolation model is subjected to weight optimization, errors are reduced, and data integrity is improved. WSMOTE parameters are adaptively combined with data distribution to synthesize samples, data are balanced, and the over-fitting risk is reduced. In practical application, the quality of coal blending model training data can be improved, and optimization of a multi-coal-source coal blending scheme is assisted.

The application provides a knowledge graph construction system and method based on a relational database, comprising a database connection module, a knowledge graph construction module and a graph editing and display module, based on form structure analysis, form association relationship identification and analysis and form basic item acquisition of the relational database, realizing graph construction and fusion integration of the relational database; based on graph visualization display, graph entity editing, graph entity relationship editing and graph extraction information configuration, realizing graph editing and display capability. The application supports graph construction of multiple data sources, breaks data islands, carries out multi-element combination of data, provides a combined information analysis basis for users, provides entity fusion integration capability, effectively improves graph availability and eliminates redundant data.

The application discloses a kind of based on hovering underwater vehicle's underwater unknown environment active mapping method, belong to robot environment exploration technical field.The underwater unknown environment active mapping method based on hovering underwater vehicle provided by the application utilizes hovering underwater vehicle to obtain the environmental data of unknown area of ocean in cooperation with sensor, determines the best next viewpoint according to information gain value, and determines the safe and feasible path to the best next viewpoint according to the cost of each adjacent node on the current tree as the parent node when the best next viewpoint is reached.Updating grid map in real time in this way, efficiently, quickly and accurately realize the construction and dynamic updating of map, and then assist underwater vehicle to realize the navigation of target area, and has broad application prospect in underwater environment exploration task and underwater structure inspection based on underwater vehicle and similar tasks.

The application belongs to the technical field of point cloud processing, and discloses a multi-modal semantic mapping method and system based on a master-slave architecture. The method comprises the following steps: S1, extracting feature points in point cloud data and calculating the covariance matrix of the neighborhood point cloud of each feature point; S2, solving the optimal pose corresponding to the minimum of the target function; S3, converting the obtained point cloud data into a world coordinate system using the optimal pose, fusing all frame point cloud data in the world coordinate system to form a three-dimensional point cloud map, projecting the three-dimensional point cloud map to a camera coordinate system, and inputting the three-dimensional point cloud map projected to the camera coordinate system into a semantic segmentation neural network to obtain the semantic label corresponding to each point cloud in the three-dimensional point cloud map, thereby achieving semantic mapping. Through the application, the problems of weak dynamic adaptability, insufficient model generalization ability and long-term running precision decay of the traditional three-dimensional semantic mapping method in a dynamic complex scene are solved.

This invention discloses an intelligent identification system and method for preventing duplicate receipts, belonging to the field of data recognition technology. The invention collects digital signatures and text information from electronic receipts, adds timestamps, and constructs historical reimbursement behavior; extracts writing features from the digital signatures to construct receipts to be detected; filters receipts within a preset interval according to timestamps, calculates writing feature similarity, and marks suspected duplicate receipts; sorts the suspected duplicate receipts to form a detection sequence, compares it with the historical reimbursement sequence, and marks it as passed if a matching sequence exists; otherwise, the first receipt is automatically reimbursed, and the rest are transferred to manual review; collects the results of manual review and updates the corresponding receipt reimbursement history. The system includes modules for data collection and construction, data feature extraction, similarity judgment, classification and comparison processing, and result recording and updating. This invention improves the accuracy of duplicate receipt identification, significantly reduces the amount of invalid manual review, and improves the efficiency of reimbursement review.

The application relates to an electroencephalogram signal processing method, device and computer equipment. The method comprises the following steps: introducing a frequency domain modeling branch on the basis of an original electroencephalogram base model structure by respectively performing time domain processing and frequency domain processing on electroencephalogram signals, realizing time domain and frequency domain dual-mode collaborative coding, and constructing a target neural codebook containing a time domain special codebook, a frequency domain special codebook and a time-frequency shared codebook. Then, the target neural codebook is used as the basis for mask pre-training, the precise construction of the target electroencephalogram model is realized, and key support is provided for efficient decoding of electroencephalogram signals and upgrading of brain-computer interface technology.

The invention provides a nuclear power plant isolation information management method, electronic equipment and a storage medium. The method comprises the following steps: initializing an isolation information source of a nuclear power plant to form a first sequence; configuring a target isolation ticket rack name, and constructing a first Hash map according to a mapping relation between the target isolation ticket rack name and the first sequence; forming a second sequence according to all isolation information which is from an isolation information source and is matched with a target isolation ticket rack name, and extracting all system names which are not repeated in the second sequence through field classification statistics to form a system name list; associating the second sequence as a child node to the first hash map; and determining a target system name from the system name list, and constructing a second hash map according to a mapping relationship between the target system name and the second sequence. According to the method and the device, the isolated ticket rack relationship can be constructed and displayed in a more efficient and more intuitive manner, so that the operation efficiency and accuracy of related businesses such as operation management and isolated management are improved.

The present application relates to a kind of refractory dispersant and its preparation method in the technical field of refractory additive, it is the comb structure copolymer, the copolymer includes styrene-maleic anhydride copolymer main chain, polyethylene glycol side chain grafted on the styrene-maleic anhydride copolymer main chain by ester bond, and phosphate radical;The polyethylene glycol side chain includes short-chain polyethylene glycol with molecular weight of 400-600 and long-chain polyethylene glycol with molecular weight of 800-1200.The present application realizes the precise division of function by using asymmetric compound polyethylene glycol side chain of specific molecular weight range, and controls esterification grafting degree is 50%-85%, not only can provide excellent initial wetting and dispersion force, ensure that slurry has excellent construction fluidity, but also can effectively prevent particle re-aggregation and sedimentation under static or shear, so as to fundamentally solve the technical problem that traditional dispersant is difficult to consider high initial fluidity and long-term anti-settling property, plasticity.

The application provides a low-orbit constellation system-oriented system model construction method and system simulation method, and belongs to the field of low-orbit constellation system simulation and performance evaluation.The construction method performs lightweight simulation modeling on functional entities of a space section, a ground section, an application section and an environment section, the model constructed by the space section comprises a constellation configuration model, an attitude and orbit control subsystem model and a satellite payload model, the ground section comprises a main gateway station model and a secondary gateway station model, a large-scale terminal model is constructed in the application section, the environment section comprises a satellite-ground microwave channel submodel and an inter-satellite laser channel submodel, and model interaction design is performed to form an integrated model architecture of satellite-ground integration.The application guarantees the modeling accuracy of functional entities, simultaneously meets the lightweight demand of simulation modeling, reduces the complexity of system modeling, balances the relationship between model accuracy and lightweight, and simulates, verifies and evaluates the correctness, rationality and effectiveness of the architecture design of the constellation system.

This invention discloses a method and device for three-dimensional electrical impedance tomography (EIT) of the thoracic cavity. The method includes acquiring a three-dimensional point cloud of the thoracic cavity region of the subject to establish a three-dimensional thoracic cavity model; performing device self-test and checking electrode fit; generating a predetermined excitation signal and injecting it into the subject; acquiring voltage signals from each electrode; separating and filtering EIT and ECG signals; performing forward problem calculation on the voltage signals based on the subject's three-dimensional thoracic cavity model to obtain the potentials of each electrode in the three-dimensional thoracic cavity model; and performing three-dimensional reconstruction using the single-step Gauss-Newton method to obtain an electrical impedance tomography map of pulmonary ventilation changes. This invention, by constructing a three-dimensional thoracic cavity model of the subject, performing forward problem calculation on the voltage signals, and further reconstructing the image, can achieve real-time, high-precision three-dimensional dynamic imaging of the subject's thoracic cavity with high imaging accuracy.

The invention discloses a construction method of a channel tight constraint model of an aperiodic semiconductor device with defects. According to the method, a supercell atomic structure is used as a feature, a density functional theory calculation energy band is used as a label, and a physical perception graph neural network integrated with a symmetric graph attention mechanism is constructed. In the feature learning and energy band fitting process, the model applies physical constraint of exponential decay to transition parameters. Through co-training defect-free and defect-containing supercells, the network can automatically analyze local perturbation caused by defects and dynamically adjust local parameters related to defect positions in a defect-free model so as to precisely fit an energy band structure of a defect system. According to the mechanism, the consistency of the super-intercellular transition matrixes of defect-containing and defect-free systems is strictly guaranteed while the model is constructed, so that a whole set of model parameters are output. According to the method, the technical bottleneck that a coupling matrix between complex systems is difficult to obtain in semiconductor material modeling is effectively solved.

The present application relates to wave simulation generation technical field, specifically relates to a kind of supergravity field wave simulation method.The supergravity field wave simulation method includes: under supergravity field, the supergravity field wave making similarity relationship between predetermined wave height and frequency dimensionless quantity is verified similarity ratio;In the case where similarity ratio is consistent, the parameter of the supergravity field wave making similarity relationship is calibrated;According to the supergravity field wave making similarity relationship of calibration parameter, supergravity field wave simulation is carried out.The present application can accurately simulate the wave of different environment under supergravity field, can accurately construct transfer function, accurately assess the influence of different motion amplitude, different frequency, different gravity acceleration and other physical quantities on wave making.

The invention provides a traffic flow prediction method based on floating car data and mutual information topology reconstruction, and the method comprises the steps: obtaining non-full-sample floating car trajectory data, and generating a traffic flow time sequence of each road node; based on the traffic flow time sequence of each road node, a mutual information value between any two road nodes is calculated, an adjacent matrix is constructed according to the mutual information values, and elements of the adjacent matrix represent a dependency relationship between the corresponding nodes; a traffic network diagram is constructed according to the adjacency matrix, the traffic network diagram comprises a node set, an edge set and the adjacency matrix, the node set represents road nodes, and the edge set represents connectivity between the nodes; taking the traffic network graph and the traffic flow time sequence as input, and training a traffic flow prediction model by using a graph neural network model; and the trained traffic flow prediction model is utilized to predict the traffic flow in the future time period and output the prediction result, so that the accuracy of traffic flow prediction is effectively improved.

This invention provides a diagnostic analysis thought chain management method and system based on human-computer interaction. The method responds to the user's diagnostic scenario selection command, calls a preset thought chain template to construct an initial diagnostic analysis thought chain, and displays it through a visual interactive interface. Based on the user's interactive dynamic adjustment of the initial diagnostic analysis thought chain through the visual interactive interface, an adjusted diagnostic analysis thought chain is obtained. This dynamic adjustment includes dynamic editing of thought chain nodes and associating the required data items of the nodes. Professional content is embedded into the adjusted diagnostic analysis thought chain and a pre-built professional knowledge base to obtain an embedded diagnostic analysis thought chain. Based on the embedded diagnostic analysis thought chain and a prompt word rule base, a prompt word sequence is generated through a pre-trained large model, solving the problems of uncontrollable reasoning processes and strong randomness of results in existing technologies for large model applications in professional fields.

The application discloses a COCE- Nozzle nozzle for forming a hollow tubular structure and a forming method, and comprises an outer shell body, a center occupying column is arranged in the outer shell body, the center occupying column is coaxially arranged with the outer shell body, the center occupying column is fixedly connected with the outer shell body through a supporting rib, and a uniform annular extrusion flow channel is formed between the center occupying column and the outer shell body. The application effectively breaks through the core bottleneck of traditional technology in material adaptability, process complexity, equipment threshold and forming stability, provides an advanced and reliable technical platform for organ chips, organoid engineering and regenerative medicine fields, and has remarkable scientific research application value and industrialization prospect.

The application discloses a SSR core primer group based on whole genome sequencing and core germplasm resequencing of Glycine max and application thereof. Specifically disclosed is the SSR core primer group, which comprises at least 5 pairs of primers (SEQ ID No. 1-460) in 230 pairs of primers. The application establishes a method for developing the whole genome SSR marker of Glycine max, which is comprehensive, accurate and reliable, and solves the problems of the current Glycine max SSR marker, such as small quantity, low polymorphism and low genome coverage. The SSR core primer group can maximize the reflection of the genetic diversity of Glycine max germplasm resources, has the characteristics of high polymorphism, uniform distribution, stable amplification, good reproducibility, clear site, clear and easy-to-distinguish statistical electrophoresis bands and the like, can accurately perform kinship analysis and diversity analysis, and is helpful to the researches such as genetic map construction, gene positioning, variety identification and variety DNA fingerprint construction, and has a wide application prospect.

The invention relates to a preparation method of a graded porous Murphy material based on cooperation of microfluidics, ink-jet printing and emulsion evaporation, and solves the technical problems that an existing preparation method of the graded porous Murphy material is harsh in condition, the porosity is difficult to regulate and control, and the prepared porous material is unstable in pore structure and low in uniformity. Silicon dioxide nano particles are introduced into an emulsion dispersion phase, self-assembly of the nano particles is driven by utilizing cohesion force generated by preferential evaporation of the dispersion phase, a silicon microsphere single-layer structure in hexagonal arrangement is formed, macroscopic pores are formed among microspheres, mesoscopic pores are formed among nano particles in the microspheres, and finally the graded porous Murphy material is obtained.

This application provides a data query method, electronic device, computer storage medium, and program product. The method includes: using a statistical language model to segment a natural language query statement into multiple corresponding query segments; constructing a structured query language (SQL) statement for querying based on the multiple query segments using regular expressions, and obtaining multiple candidate query results by executing the SQL statement; extracting the longest common substring from each of the multiple candidate query results and the natural language query statement to obtain a target common substring; and determining the target query result that responds to the natural language query statement from the multiple candidate query results based on the target common substring. Therefore, this method can improve data query efficiency and the accuracy of query results, thereby meeting the user's query needs.

The invention relates to a method and system for detecting dam defects based on muon rays, and belongs to the technical field of dam detection.The method comprises the steps that muon projection data obtained when muon beams penetrate through a dam to be detected are divided according to a plurality of projection directions, and a density distribution curve of each projection direction is calculated; obtaining a density distribution matrix for representing the density distribution of the dam to be detected according to the density distribution curves in all the projection directions and a pre-constructed geometrical relationship matrix between the detector and the pixels of the dam to be detected; based on the density distribution matrix, calling an image reconstruction algorithm in which a SART algorithm and a POCS algorithm are fused in advance, and performing reconstruction optimization on the muon imaging process to obtain a reconstructed dam image; defect position identification is carried out on the reconstructed dam image, a dam defect detection result is obtained, the characteristics of high penetrability and weak interaction of muons are ingeniously applied, an image reconstruction algorithm in which data driving updating and prior constraint projection are alternately carried out is combined, and the dam defects can be accurately detected.

The embodiment of the application discloses a kind of tailing pond drainage monitoring method and device, applicable to coal mine safety monitoring field, which comprises: obtaining the surveying and mapping data information of target tailing pond collected by unmanned aerial vehicle, three-dimensional modeling of the target tailing pond is carried out based on surveying and mapping data information, the inclined image model and three-dimensional model of target tailing pond are obtained, according to inclined image model and three-dimensional model, the semantic segmentation of target tailing pond is carried out, and the data information of different monitoring objects of target tailing pond is obtained, according to the data information of monitoring object, the drainage anomaly identification of monitoring object is carried out, and according to the identification result of monitoring object, the drainage monitoring data of target tailing pond is generated.In the embodiment of the application, based on the surveying and mapping data information collected by unmanned aerial vehicle, accurate inclined image model and three-dimensional model are constructed, so as to identify the drainage anomaly of tailing pond based on the model, no longer rely on artificial inspection, improve the efficiency, reliability and accuracy of tailing pond drainage monitoring.