Trace Length Research Articles

Utilizing semantic-level computer vision for fracture trace characterization of hard rock pillars in underground space

This study utilizes a semantic-level computer vision-based detection to characterize fracture traces of hard rock pillars in underground space. The trace images captured by photogrammetry are used to establish the database for training two convolutional neural network (CNN)-based models, i.e., U-Net (University of Freiburg, Germany) and DeepLabV3+ (Google, USA) models. Chain code technology, polyline approximation algorithm, and the circular window scanning approach are combined to quantify the main characteristics of fracture traces on flat and uneven surfaces, including trace length, dip angle, density, and intensity. The extraction results indicate that the CNN-based models have better performances than the edge detection methods-based Canny and Sobel operators for extracting the trace and reducing noise, especially the DeepLabV3+ model. Furthermore, the quantization results further prove the reliability of extracting the fracture trace. As a result, a case study with two types of traces (i.e., on flat and uneven surfaces) demonstrates that the applied semantic-level computer vision detection is an accurate and efficient approach for characterizing the fracture trace of hard rock pillars.

EstraNet: An Efficient Shift-Invariant Transformer Network for Side-Channel Analysis

Deep Learning (DL) based Side-Channel Analysis (SCA) has been extremely popular recently. DL-based SCA can easily break implementations protected by masking countermeasures. DL-based SCA has also been highly successful against implementations protected by various trace desynchronization-based countermeasures like random delay, clock jitter and shuffling. Over the years, many DL models have been explored to perform SCA. Recently, Transformer Network (TN) based model has also been introduced for SCA. Though the previously introduced TN-based model is successful against implementations jointly protected by masking and random delay countermeasures, it is not scalable to long traces (having a length greater than a few thousand) due to its quadratic time and memory complexity. This work proposes a novel shift-invariant TN-based model with linear time and memory complexity. he contributions of the work are two-fold. First, we introduce a novel TN-based model called EstraNet for SCA. EstraNet has linear time and memory complexity in trace length, significantly improving over the previously proposed TN-based model’s quadratic time and memory cost. EstraNet is also shift-invariant, making it highly effective against countermeasures like random delay and clock jitter. Secondly, we evaluated EstraNet on three SCA datasets of masked implementations with random delay and clock jitter effect. Our experimental results show that EstraNet significantly outperforms several benchmark models, demonstrating up to an order of magnitude reduction in the number of attack traces required to reach guessing entropy 1.

Delineating homogeneous domains of fractured rocks using topological manifolds and deep learning

Determining homogeneous domains statistically is helpful for engineering geological modeling and rock mass stability evaluation. In this text, a technique that can integrate lithology, geotechnical and structural information is proposed to delineate homogeneous domains. This technique is then applied to a high and steep slope along a road. First, geological and geotechnical domains were described based on lithology, faults, and shear zones. Next, topological manifolds were used to eliminate the incompatibility between orientations and other parameters (i.e. trace length and roughness) so that the data concerning various properties of each discontinuity can be matched and characterized in the same Euclidean space. Thus, the influence of implicit combined effect in between parameter sequences on the homogeneous domains could be considered. Deep learning technique was employed to quantify abstract features of the characterization images of discontinuity properties, and to assess the similarity of rock mass structures. The results show that the technique can effectively distinguish structural variations and outperform conventional methods. It can handle multisource engineering geological information and multiple discontinuity parameters. This technique can also minimize the interference of human factors and delineate homogeneous domains based on orientations or multi-parameter with arbitrary distributions to satisfy different engineering requirements.

The combined research of ultra-high vacuum CF flange joints' sealing parameters considering plastic properties of materials

Computer simulation and experimental research of the tightening processes of ultrahigh vacuum CF flange joints have been carried out. Finite element analyses were carried out considering the plastic properties of materials. The analysis variable parameters are flanges' knife edge angle between the shelves (Wheeler's and CERN's models), tip rounding radiuses, and gasket material state (annealed and hard). Curves of changes in the stress and strain intensities of the edge nodes of the flanges' knife edge were obtained. Essential sealing parameters of the ultrahigh vacuum system were also studied, such as the height of the knife edge, the length of the knife-edge trace on the gasket (in the radial direction), and the gap between two flanges. The mentioned sealing parameters' measurements were carried out by the combined method. The latter is a parameters' measurement of both computer simulation and experimental samples and a comparison of the obtained results. It should be noted that the sealing parameters were studied for several tightening cycles of the flanges to research their changes in case of multiple uses. The vital value of this research is obtained empirical functions for calculating the height of the flanges' knife edge based on the tightening cycles.

Semi‐automatic identification of discontinuity parameters in rock masses based on Unmanned Aerial Vehicle photography

Efficient and accurate extraction of discontinuity geometric parameters is significant for evaluating the stability and seepage characteristics of a rock mass. Traditional means of rock discontinuity measurement are susceptible to the influence of terrain and have issues such as high operational workload and low efficiency. An approach was proposed to comprehensively and efficiently obtain the geometric parameter information of the discontinuity, using an Unmanned Aerial Vehicle (UAV), which consists of the following five procedures: (1) measurement of a rock slope with UAV, (2) creation of three‐dimensional (3D) point cloud model for the slope, (3) voxel filtering of point cloud data, (4) planar segmentation based on modified region growing (MRG) algorithm, and (5) acquisition of parameter set of the discontinuity (orientation, trace length, and spacing). A new code, FacetDetect, has been developed based on this method to identify discontinuity from a 3D point cloud. Meanwhile, the trace length and spacing are calculated by the code written in Python. A comparison with the three‐point method reveals that most errors are less than 3° for dip angles and dip directions. These deviations are reasonable and confirm the reliability of the method. Overall, this method is a valuable reference for automatic discontinuity interpretation and related fields.

Estimation of Fracture Size and Probability Density Function by Setting Scanlines in Rectangular Sampling Window

Abstract Rock masses are very important materials in geotechnical engineering. In engineering rock mass, fracture is the relatively weak part of mechanical strength in rock mass and is the most important factor controlling the deformation, damage, and permeability of rock mass. Therefore, investigating fractures is very important for characterizing rock mass. This paper proposed a new approach by using uniformly equidistant orthogonal scanlines. Within the study context, the solution formula of fracture size is derived by establishing the space intersection model of arbitrary fracture and scanline, rectangular window, and a rectangular box with a rectangular window. Then, fractures were randomly generated in a certain size cube and compared with the traditional Kulatilake trace length integral evaluation method. The study results have shown that the proposed method is more reasonable and accurate. Then, this method was applied to an adit of Songta Hydropower Station. Finally, a new fracture diameter probability density estimation method was proposed, the fracture diameter of the normal distribution was verified, and the parameters of the probability density function obtained by the scanlines method were in agreement with the initial set parameters. In summary, the proposed scanlines method can well estimate the mean value of the fracture diameter and the probability density function of the fracture size.

The clinical significance of electronic fetal heart rate monitoring in twins.

Fully effective intrapartum cardiotocographic (CTG) fetal heart monitoring is still missing. Visual analysis is far from credibility. Additional, computerized analysis techniques were proposed however they did not substantially decrease possible risks of fetal asphyxia. In twin pregnancies the problem is even more complicated. Our goal is to find the most valuable parameters in intrapartum CTG surveillance in twins, based on actual FIGO criteria. Study included 58 women in labor who had been admitted to Delivery Department of tertiary care hospital with twin pregnancy in a period of one year. The features of the CTG (e.g., baseline, oscillation, decelerations, brady- or tachycardia) were grouped to create three variables that were closest to the FIGO CTG scale. All three groups were compared according to neonatal status (Apgar score at 5 min ≥ 7 or < 7; pH value in umbilical artery ≥ 7.20, < 7.20 or < 7.10 and BE (base excess) > or ≤ -12). Fetal status and its acid - base equilibrium was compared either with long term variability (LTV), short term variability (STV), or percentage of the signal loss. Out of 58 twin pregnancies, a total of 116 babies were born. One baby was born dead. From this group, 11 deliveries were natural births and 47 deliveries were C-sections. None of the analyzed features (pH, BE, Apgar, CTG features except tracing length, CTG FIGO categories) were statistically different between groups of singleton and twin pregnancies, except percentage of C-sections. No differences were found either for STV or LTV and fetal status.org CTG categories. Prior to cardiotocographic tracing of twins during labor, ultrasound examination should be mandatory. Considerable loss of signal in CTG tracing in twins should provoke ultrasonographic confirmation of the fetal status.

Discontinuity development patterns and the challenges for 3D discrete fracture network modeling on complicated exposed rock surfaces

Natural slopes usually display complicated exposed rock surfaces that are characterized by complex and substantial terrain undulation and ubiquitous undesirable phenomena such as vegetation cover and rockfalls. This study presents a systematic outcrop research of fracture pattern variations in a complicated rock slope, and the qualitative and quantitative study of the complex phenomena impact on three-dimensional (3D) discrete fracture network (DFN) modeling. As the studies of the outcrop fracture pattern have been so far focused on local variations, thus, we put forward a statistical analysis of global variations. The entire outcrop is partitioned into several subzones, and the subzone-scale variability of fracture geometric properties is analyzed (including the orientation, the density, and the trace length). The results reveal significant variations in fracture characteristics (such as the concentrative degree, the average orientation, the density, and the trace length) among different subzones. Moreover, the density of fracture sets, which is approximately parallel to the slope surface, exhibits a notably higher value compared to other fracture sets across all subzones. To improve the accuracy of the DFN modeling, the effects of three common phenomena resulting from vegetation and rockfalls are qualitatively analyzed and the corresponding quantitative data processing solutions are proposed. Subsequently, the 3D fracture geometric parameters are determined for different areas of the high-steep rock slope in terms of the subzone dimensions. The results show significant variations in the same set of 3D fracture parameters across different regions with density differing by up to tenfold and mean trace length exhibiting differences of 3–4 times. The study results present precise geological structural information, improve modeling accuracy, and provide practical solutions for addressing complex outcrop issues.

Automated mapping of bedrock-fracture traces from UAV-acquired images using U-Net convolutional neural networks

This contribution presents a novel U-Net convolutional neural network (CNN)-based workflow for automated mapping of bedrock fracture traces from 0.55 cm spatial resolution aerial photographs, acquired by unmanned aerial vehicles (UAV), over the Wiborg Rapakivi granite outcrops in the islands off the coast of the Loviisa Region in Southern Finland. The workflow comprised training a U-Net CNN using a small subset of photographs with manually traced fractures for optimizing the network parameters using the root mean squared propagation optimizer and sigmoidal focal loss function for semantic segmentation of input images and pixel-wise identification of fracture traces. The ridge detection algorithm was then applied to the U-Net prediction results, followed by vectorization of the fracture-traces pixels as vector polylines representing the traces of fractures. Both intensity values of the pixels and topological connectivity were used in the process of vectorization. Quantitatively the results were assessed using various accuracy assessment metrics. Qualitative evaluations of the results were implemented by comparisons of orientations and length-frequency distributions of automatically- and manually-mapped traces.The results show that the model has the class-balanced accuracy score 0.945, predicting 88.79% of the fracture-trace pixels. Bedrock outcrops with well-exposed surfaces present high true positive rates (>99%). The demonstration (test) site has the class-balanced accuracy score of 0.873 and 75% true positive rate. Additionally, the fracture trace networks replicate the orientation distributions of the manually digitized traces. The length distributions of automatic traces, however, differ with varying intensity from the manual trace length distributions. However, this study demonstrates that the workflow can be successfully applied to UAV-acquired images for fast and efficient automated mapping of bedrock-fracture traces during the initial phases of structural characterization of a region.

A method to interpret fracture aperture of rock slope using adaptive shape and unmanned aerial vehicle multi-angle nap-of-the-object photogrammetry

The aperture of natural rock fractures significantly affects the deformation and strength properties of rock masses, as well as the hydrodynamic properties of fractured rock masses. The conventional measurement methods are inadequate for collecting data on high-steep rock slopes in complex mountainous regions. This study establishes a high-resolution three-dimensional model of a rock slope using unmanned aerial vehicle (UAV) multi-angle nap-of-the-object photogrammetry to obtain edge feature points of fractures. Fracture opening morphology is characterized using coordinate projection and transformation. Fracture central axis is determined using vertical measuring lines, allowing for the interpretation of aperture of adaptive fracture shape. The feasibility and reliability of the new method are verified at a construction site of a railway in southeast Tibet, China. The study shows that the fracture aperture has a significant interval effect and size effect. The optimal sampling length for fractures is approximately 0.5–1 m, and the optimal aperture interpretation results can be achieved when the measuring line spacing is 1% of the sampling length. Tensile fractures in the study area generally have larger apertures than shear fractures, and their tendency to increase with slope height is also greater than that of shear fractures. The aperture of tensile fractures is generally positively correlated with their trace length, while the correlation between the aperture of shear fractures and their trace length appears to be weak. Fractures of different orientations exhibit certain differences in their distribution of aperture, but generally follow the forms of normal, log-normal, and gamma distributions. This study provides essential data support for rock and slope stability evaluation, which is of significant practical importance.

Three-dimensional laser scanning and numerical investigation on the influence of freeze-thaw and hang-wall mining on the instability of an open-pit slope

The instability of the open-pit slope and associated disasters of complex orebodies such as hanging-wall mining are the key problems to be solved urgently in the development of western resources. In this work, taking the hanging-wall mining in the open-pit mine of Hejing iron mine, for example, the disaster mechanism influenced by the coupling freeze-thaw and hanging-wall mining is systematically studied by 3D laser scanning and numerical simulation. Firstly, the rock mass structure information such as dip, dip angle, spacing, and equivalent trace length characteristics was obtained using 3D intelligent recognition technology. Then, numerical simulation is employed to reveal the influence of freeze-thaw and excavation sequences on the overall stability of the open-pit slope. The stress, displacement, plasticity zone, and maximum shear strain patterns are revealed in detail. The results show that the excavation engineering will lead to frequent increase and unloading of the internal stress of the rock mass, and the gradual increase of the goaf area will cause great damage to the rock mass. The slope failure mode is strongly impacted by freeze-thaw weathering and orebody excavation.

A novel system for multivariate analysis of discontinuities in fractured rock masses based on manifold learning and fractal models

The engineering-geological characteristics of fractured rock masses depend on the discontinuity properties, which can be analyzed by the stereonet-based system. However, this system faces challenges in describing orientations, which are spherical data, and it cannot incorporate other scalar parameters (e.g., trace length, aperture, etc.) that affect engineering practice. Therefore, a novel system based on manifold learning is proposed to analyze the distribution patterns of orientation data and characterize multiple discontinuity properties. The proposed system uses manifold learning to explore and visualize the manifold structure of orientation data by a two-dimensional kernel density estimation (2D-KDE) technique. It also integrates other parameters into the manifold structure to capture multiple properties. To quantify the manifold structure and reveal the real fractal behaviors of orientation data, a detailed analysis process including monofractal and multifractal models is proposed. The effectiveness of the proposed system is verified by comparison with the stereonet-based system in several aspects. The equivalent manifold structure is also proposed to enhance the engineering applicability of the system, and one of its applications is demonstrated. Finally, the proposed system is applied to a significant road project and further developed by unmanned aerial vehicle (UAV) photogrammetry. The proposed system provides new insights for research on fractured rock masses and has great potential for solving multi-parameter problems in engineering geology.

Morphological classification method and data-driven estimation of the joint roughness coefficient by consideration of two-order asperity

Abstract The roughness of the joint surface plays a significant role in evaluating the shear strength of rock. The waviness (first-order) and unevenness (second-order) of natural joints have different effects on the characterization of joint surface roughness. To accurately quantify the influence of the two-order asperity on the joint roughness coefficient (JRC) prediction of joint surface profile curve, the optimal sampling interval of the asperity was determined through the change of the R p {R}_{{\rm{p}}} value of the joint surface profile curve. The separation of the two-order asperity of 48 joint surface profile curves was completed at the optimal sampling interval, and morphological parameters of the asperity such as i ave {i}_{{\rm{ave}}} , R max {R}_{{\rm{\max }}} , and R p {R}_{{\rm{p}}} were counted from three aspects: asperity angle of the profile curve, asperity degree, and the trace length. Based on the statistical results of the morphological parameters considering the two-order asperity, the new nonlinear prediction models were proposed. The results showed that the curve slope mutation point SI = 2 mm is the optimal separation distance of the two-order asperity of the joint surface profile curve. The refined separation method that considers the waviness and unevenness of morphological parameters can characterize the detailed morphological features of the joint surface in more dimensions. The support vector regression (SVR) and random forest (RF) models that take into account a two-order asperity separated results have higher accuracy than traditional models. The prediction accuracy has improved by 7–8% in SVR model compared with SVR(SO) and RF(SO). The SVR nonlinear model that considering separation of two-orders of joint surface roughness is more suitable for the prediction of JRC.

Estimation of REV size of 2-D DFN models in nonlinear flow: Considering the fracture length-aperture correlation

Determining the representative elementary volume (REV) of fractured rock masses is the foundation for studying the properties of such rock masses using the equivalent continuum model. This paper focuses on estimating the REV sizes of a fractured rock mass, considering the linked trace length and fracture aperture in both linear and nonlinear flow regimes. To achieve this, Monte Carlo simulations were employed to create discrete fracture network (DFN) models based on the geometric characteristics of fractures. The linear element method, modified by the Forchheimer law, was used to calculate the equivalent permeability coefficient tensor K and the equivalent non-Darcy coefficient tensor β. These calculations were performed to determine the REV size of DFNs under nonlinear flow conditions. The findings of this study demonstrate a general consistency in the computed K values for the two flow regimes. It was observed that the REV size, determined by β value, exceeded that obtained using K for the identical fracture network. Furthermore, when considering the same flow regime, the REV size was found to be smallest when the fracture aperture remained constant, followed by cases where it was independent of the trace length and finally when it was correlated with the trace length.

Automatic identification of rock discontinuity and stability analysis of tunnel rock blocks using terrestrial laser scanning

Local geometric information and discontinuity features are key aspects of the analysis of the evolution and failure mechanisms of unstable rock blocks in rock tunnels. This study demonstrates the integration of terrestrial laser scanning (TLS) with distinct element method for rock mass characterization and stability analysis in tunnels. TLS records detailed geometric information of the surrounding rock mass by scanning and collecting the positions of millions of rock surface points without contact. By conducting a fuzzy K-means method, a discontinuity automatic identification algorithm was developed, and a method for obtaining the geometric parameters of discontinuities was proposed. This method permits the user to visually identify each discontinuity and acquire its spatial distribution features (e.g. occurrences, spacings, trace lengths) in great detail. Compared with hand mapping in conventional geotechnical surveys, the geometric information of discontinuities obtained by this approach is more accurate and the identification is more efficient. Then, a discrete fracture network with the same statistical characteristics as the actual discontinuities was generated with the distinct element method, and a representative numerical model of the jointed surrounding rock mass was established. By means of numerical simulation, potential unstable rock blocks were assessed, and failure mechanisms were analyzed. This method was applied to detection and assessment of unstable rock blocks in the spillway and sand flushing tunnel of the Hongshiyan hydropower project after a collapse. The results show that the noncontact detection of blocks was more labor-saving with lower safety risks compared with manual surveys, and the stability assessment was more reliable since the numerical model built by this method was more consistent with the distribution characteristics of actual joints. This study can provide a reference for geological survey and unstable rock block hazard mitigation in tunnels subjected to complex geology and active rockfalls.

Estimation of fracture size and azimuth in the universal elliptical disc model based on trace information

The geometric characteristics of fractures within a rock mass can be inferred by the data sampling from boreholes or exposed surfaces. Recently, the universal elliptical disc (UED) model was developed to represent natural fractures, where the fracture is assumed to be an elliptical disc and the fracture orientation, rotation angle, length of the long axis and ratio of short-long axis lengths are considered as variables. This paper aims to estimate the fracture size- and azimuth-related parameters in the UED model based on the trace information from sampling windows. The stereological relationship between the trace length, size- and azimuth-related parameters of the UED model was established, and the formulae of the mean value and standard deviation of trace length were proposed. The proposed formulae were validated via the Monte Carlo simulations with less than 5% of error rate between the calculated and true values. With respect to the estimation of the size- and azimuth-related parameters using the trace length, an optimization method was developed based on the pre-assumed size and azimuth distribution forms. A hypothetical case study was designed to illustrate and verify the parameter estimation method, where three combinations of the sampling windows were used to estimate the parameters, and the results showed that the estimated values could agree well with the true values. Furthermore, a hypothetical three-dimensional (3D) elliptical fracture network was constructed, and the circular disc, non-UED and UED models were used to represent it. The simulated trace information from different models was compared, and the results clearly illustrated the superiority of the proposed UED model over the existing circular disc and non-UED models.

An Estimation Method for EMI Radiated Emissions Using Measured Source Voltages

A method applicable for estimating radiated emissions from printed circuit board traces and connecting cables is proposed. Empirical formulae are derived to predict emission levels in a conventional 10 m semianechoic chamber in the 30–1000 MHz range, which is required for electromagnetic compatibility/electromagnetic interference (EMI) tests in CISPR 32 and EN 55032. The objective of the proposed technique is to facilitate product and component EMI compliance evaluations in the early design stage. Instead of time-consuming measurement processes within the range, estimations can be made in terms of near-field probing results and transformation formulae. According to trace and cable lengths, either long- or short-length mode equations can be employed. Estimations of mock-up and actual circuit boards made with the proposed method were compared with 10 m measurement range results to validate the effectiveness of this approach. Good agreements are observed. This method can be a time-efficient and cost-effective diagnosis tool for products required to pass the EMI compliance test.

Multi-index dominant grouping of rock mass discontinuities based on the combined weighting method: A case study for the Huayang tunnel

The properties of discontinuities are determined by their occurrence, trace length, aperture, roughness, and the degree of particle fill; therefore, a multi-index dominant grouping method for rock mass discontinuities based on the combined weighting method was proposed. Firstly, the combined weighting method was used to calculate the weighted value of each index participating in the similarity measurement, and a reasonable elimination of outlier discontinuities is achieved based on the principle of possibility clustering. The adaptive chaotic annealing particle swarm optimization algorithm was then used to search the global optimal initial clustering centers of the fuzzy C-means clustering algorithm. The objective function was established by minimizing the weighted sum of the distance between the discontinuities to be grouped, and the clustering centers to complete the multi-index dominant grouping of rock mass discontinuities. 230 artificial discontinuities with outliers were grouped and compared with other methods, which indicated that this method has higher grouping accuracy. The proposed method was applied to group the measured discontinuities of the Huayang tunnel in Chongqing City, China. Based on the grouping results, a discrete element model for tunnel excavation was established, and the construction was guided according to the calculated results from the model. The engineering applicability of the method was further verified.

Multi-Factor Analysis on the Stability of High Slopes in Open-Pit Mines

During the production of open-pit mines, the stability of slopes can be affected by various factors such as structural surfaces, production blasting vibrations, and mining areas. In this study, the researchers focused on the slope of the open-pit mine at Yinshan and employed UAV mapping technology to conduct an on-site geological engineering investigation. Information on the yield, trace length, spacing, and density of the structural surface of the south slope was obtained. The researchers also carried out vibration blasting tests in combination with the production blasting activities in the mine to determine the blasting vibration attenuation law and whether the blasting vibration speed met safety specifications. Additionally, numerical simulation methods were used to examine the influence of the mining area on the stability of the current slope and the designed excavation slope. The slope stability was evaluated using the limit equilibrium method, and the researchers separately discussed the influence of self-weight load and self-weight load plus blasting vibration force on the stability of the high slope of the open pit. The results showed the following: (1) The rock mass structural plane in the south slope of the mining area was mainly dominated by a medium-large dip structural plane, and three faults and joint fissures in the investigation area combined to form cutting and sliding surfaces in the rock mass that were prone to collapse and sliding. (2) The maximum blasting vibration speed met safety requirements. (3) There was no large range of plastic zone damage in the entire slope, and the overall stability of the slope was good. (4) The present slope was relatively stable when considering only self-weight stress and the blasting vibration force. However, there was a certain risk of instability in the design of the excavation slope.

The AliveCor KardiaMobile ECG device allows electrocardiogram assessment in awake bonobos (Pan paniscus).

To determine the diagnostic utility of a smartphone-based ECG device (Alivecor KardiaMobile) in awake bonobos (Pan paniscus). 7 adult bonobos in human care. Bonobos were trained with positive reinforcement to hold 1 finger from each hand onto the KardiaMobile sensors for 30 seconds to obtain an ECG reading. Ten ECG tracings were recorded from each bonobo and evaluated by a veterinarian, a veterinary cardiologist, and a human cardiologist for tracing quality, tracing length, heart rate, identification of P-waves, and presence and quantification of premature ventricular or atrial contractions. 6 of the 7 bonobos were trained within 21 weeks to allow the collection of 10 diagnostic quality ECG tracings. The average heart rate recorded was 87 bpm (range = 60 to 118 bpm). Potential abnormalities identified by the KardiaMobile included premature ventricular contractions in 2 male bonobos and 1 premature atrial contraction in another male. There was strong agreement by reviewers in all ECG parameters except for the identification of P-waves. The Alivecor KardiaMobile device has diagnostic utility as a screening tool for use in bonobos in human care. The training was accomplished to yield diagnostic ECG readings of acceptable duration in awake bonobos. Given the prevalence of cardiovascular disease in great apes, this technology may identify a subset of great apes who may benefit from early intervention and treatment in an effort to delay the progression of cardiac disease.