Pattern Map Research Articles

Multi-Level Dynamic Analysis of Landscape Patterns of Chinese Megacities during the Period of 2016–2021 Based on a Spatiotemporal Land-Cover Classification Model Using High-Resolution Satellite Imagery: A Case Study of Beijing, China

In today’s accelerating urbanization process, timely and effective monitoring of land-cover dynamics, landscape pattern analysis, and evaluation of built-up urban areas (BUAs) have important research significance and practical value for the sustainable development, planning and management, and ecological protection of cities. High-spatial-resolution remote sensing (HRRS) images have the advantages of high-accuracy Earth observations, covering a large area, and having a short playback period, and they can objectively and accurately provide fine dynamic spatial information about the land cover in urban built-up areas. However, the complexity and comprehensiveness of the urban structure have led to a single-scale analysis method, which makes it difficult to accurately and comprehensively reflect the characteristics of the BUA landscape pattern. Therefore, in this study, a joint evaluation method for an urban land-cover spatiotemporal-mapping chain and multi-scale landscape pattern using high-resolution remote sensing imagery was developed. First, a pixel–object–knowledge model with temporal and spatial classifications was proposed for the spatiotemporal mapping of urban land cover. Based on this, a multi-scale district–BUA–city block–land cover type map of the city was established and a joint multi-scale evaluation index was constructed for the multi-scale dynamic analysis of the urban landscape pattern. The accuracies of the land cover in 2016 and 2021 were 91.9% and 90.4%, respectively, and the kappa coefficients were 0.90 and 0.88, respectively, indicating that the method can provide effective and reliable information for spatial mapping and landscape pattern analysis. In addition, the multi-scale analysis of the urban landscape pattern revealed that, during the period of 2016–2021, Beijing maintained the same high urbanization rate in the inner part of the city, while the outer part of the city kept expanding, which also reflects the validity and comprehensiveness of the analysis method developed in this study.

ANALYSIS THE ENVIRONMENTAL SUPPORT CAPACITY BASED ECOSYSTEM SERVICES TO BASIC DIRECTIONS FOR ADJUSTING THE SPACE PATTERN IN WACO REGENCY

Wajo Regency ecosystem has an abundance of natural and ecological resources with great potential. However, the rapid pace of development activities followed by rapid land conversion has put the sustainability of the supporting ecosystems under pressure. Therefore, it is necessary to map the carrying capacity of the environment based on ecosystem services in Wajo Regency in order to identify the fit between environmental carrying capacity and development in Wajo Regency. Research is at Wajo Regency, through the identification of land cover. ecosystem service-based land capability based analysis is conducted using an Analysis Hierarchy Process to determine the value of ecosystem services from four classes of environmental services, namely water supply, food supply, natural disaster prevention and runoff, and flood management. Instructions for completing spatial patterns in Wajo Regency are performed by analyzing the overlap of the ecosystem service-based bearing capacity map with the Wajo Regency spatial pattern map to obtain a class of spatial pattern alignment. The orientation class is based on the carrying capacity of the land capability based based on ecosystem services to optimize land cover in Wajo Regency. Results of this study show that the land capability based of the four examined ecosystem services in Wajo Regency is dominated by high and low classes. The results of the evaluation of the RTRW by Wajo Regency show that an area of 42,048.97 ha corresponds to the carrying capacity based on ecosystem services. An area of 199,454.11 hectares of land is less oriented, but most of it is retained based on the direction of the spatial pattern. In terms of environmental sustainability based on ecosystem services, the most important land accesses are in the designated settlement areas, other protected areas and local protected areas.

A Multi criteria Decision Making based nonparametric method of fragments to disaggregate daily precipitation

This study addresses the issue of scant availability of sub-daily precipitation data by introducing a novel selection methodology named ‘Pattern Mapping’ (PM) within the existing Method of Fragments (MOF) framework for the disaggregation of daily precipitation. PM introduces multiple statistics based criterion in the selection of fragments thus enhancing accuracy of the selection process. The performance of deterministic and stochastic versions of PM-MOF is compared with three widely used disaggregation methods, namely K Nearest Neighbour based MOF (KNN-MOF), Bartlett-Lewis Rectangular Pulse model (using HYETOS software package) and Micro-Canonical Cascade (MCC) using reanalysis data at 14 global locations spanning various climatic zones. It is seen that the PM-MOF method has considerably lower percentage error in replicating the standard statistics (−50.2 to 50.3% for stochastic PM-MOF and −7.4 to 13.2% for deterministic PM-MOF) when compared to existing methods (KNN-MOF (−65.4 to 76.2%), HYETOS (−78.3 to 69.4%) and MCC (−63.1 to 72%)). The comparison of densities using skill score show that skill score of PM-MOF is 0.97 which is higher than other methods (0.94 for KNN-MOF, 0.83 for HYETOS and 0.85 for MCC). Control experiments designed around varying length of training data and stochastic/deterministic mode (of PM-MOF) ascertain the contribution of the novel methodological improvements in the superior performance of PM-MOF. The robustness of the methodology and geography independent performance of PM-MOF makes it a potent candidate for wider application in hydrological and climate studies.

PEMANFAATAN TEKNOLOGI SISTEM INFORMASI GEOGRAFI UNTUK PEMETAAN POLA ALIRAN AIR TANAH DI KECAMATAN LIMBOTO

Limboto Subdistrict, which is the capital of Gorontalo Regency, has fairly high population growth and is an area that is vulnerable to the effects of drought. This causes the availability of groundwater to decrease. This study aims to utilize the GIS application to determine the pattern of groundwater flow in the Limboto District. This groundwater flow pattern can be used as a reference for further research related to groundwater. The type of data in this study is the type of primary data. The method used in this research is a survey method, namely by measuring directly in the field. The data analysis technique used to determine the pattern of groundwater flow in Limboto Regency is utilizing software (GIS) using ArcGIS 10.7 software to obtain a map of groundwater flow patterns in Limboto District. The results of the spatial analysis of the groundwater flow pattern map in Limboto District show that water flows from the northern part of the study site to the southern part of the study site.

Patterns of Transnational Crime in The Border of Sulawesi Sea - Sulu Sea and Threats to Indonesia’s Maritime

The rise of transnational crime cases in globalization is fatal if countries with maritime areas do not notice it. It is undoubtedly very influential with the threat to the security of the country's territory. Many transnational crime cases arise in the area between the Sulu Sea and the Sulawesi Sea belonging to Indonesia and the Philippines. The case came from these two countries and other countries both in the Region and those not included in the Southeast Asia Region and has confused the maritime area of the Sulu Sea with the Sulawesi Sea. Not only is the threat coming for the Philippines, but the one that has the most impact is the Indonesian defense area because of the emergence of maritime security threats. So, the concept used to find the many patterns of transnational crime cases has emerged using "maritime security" from Christian Bueger. He explained that the understanding of maritime security is disrupting in terms of defense and terms of economic, political, and geo-strategy. From the analysis and mapping of transnational crime patterns in the Sulu Sea - Sulawesi Sea, it is still a threat to Indonesia's maritime security if Indonesia does not strengthen its defense and minimize transnational criminal activities in the Philippines' border sea area and Indonesia. Literature studies and field research are methods used to analyze maritime security themes.

The Playground Shade Index: A New Design Metric for Measuring Shade and Seasonal Ultraviolet Protection Characteristics of Parks and Playgrounds.

Current shading strategies used to protect outdoor playgrounds from harmful solar radiation include the placement of artificial cloth weaves or permanent roofing over a playground site, planting trees in proximity to playground equipment, and using vegetation or surface texture variations to cool playground surfaces. How and where an artificial shade structure is placed or a tree is planted to maximize the shade protection over specific playground areas, requires careful assessment of local seasonal sun exposure patterns. The Playground Shade Index (PSI) is introduced here as a design metric to enable shade and solar ultraviolet exposure patterns to be derived in an outdoor space using conventional aerial views of suburban park maps. The implementation of the PSI is demonstrated by incorporating a machine learning design tool to classify the position of trees from an aerial image, thus enabling the mapping of seasonal shade and ultraviolet exposure patterns within an existing 7180 m2 parkland. This is achieved by modeling the relative position of the sun with respect to nearby buildings, shade structures, and the identified evergreen and deciduous tree species surrounding an outdoor playground.

Developing adiabatic two-phase flow after an expansion valve: Flow development in an 8 mm tube

This paper presents the developing two-phase flow after an expansion valve. R134a with 1.3% POE32 is used as a working medium. The flow patterns are visualized from 15 mm until 595 mm after the expansion valve in a straight tube with an inner diameter of 8 mm. The experiments cover the mass flux from 100 to 480 kg m−2 s−1 and the range of quality from 0.002 to 0.500. The observed flow patterns are classified into four regions as two-phase flow progresses along the tube: well-mixed, separating, separated but developing, and fully developed. Due to the sudden expansion in TEV, the flow structure in the well-mixed region is similar to homogeneous flow, with bubbles or droplets dispersed uniformly. Then, the gravity/buoyancy force becomes more dominant over inertia and surface tension because of the reduction of liquid velocity and the growth of bubbles. Consequently, bubbles migrate upwards while droplets fall downward, characterizing the separating region. After phase separation, the flow characteristics may still change for a certain distance before the flow is fully developed. Based on the observed flow regimes at various working conditions, a 3D flow pattern map is built, adding the distance from the expansion valve as the third dimension besides the mass flux and quality. In a following paper, the authors will discuss the effect of tube diameter, oil, and structure of expansion devices on developing two-phase flow. The developed flow patterns will be compared with the existing flow pattern map in steady conditions as an asymptote.

Microgravity two-phase flow research in the context of vapor compression cycle experiments on parabolic flights

Research on two-phase channel flow in microgravity has extensively investigated flow regimes, pressure drop, and heat transfer during evaporation and condensation processes over several decades. This literature has been primarily motivated by the goal of enabling future space applications for two-phase thermal management systems, among them vapor compression refrigeration cycles. However, relative to the number of two-phase channel flow experiments, research on vapor compression cycles in microgravity has been almost non-existent. This paper reviews two-phase flow research and compares key outcomes with those from system-level measurements obtained from recent testing of a vapor compression cycle at varying inclination angles and on parabolic flights. Previous two-phase channel flow experiments have resulted in several microgravity-specific flow regime maps and have also generally found reduced condensation heat transfer coefficients in microgravity as compared to normal gravity. The flow pattern map of Jayawardena et al. (1997) and generally reduced condensation heat transfer are confirmed by the vapor compression cycle experiments. Regarding evaporation heat transfer coefficients and friction factors, there is not a consensus in the literature on the effects of microgravity in two-phase channel flows. Similarly, the system-level experiments do not show repeatable increases or decreases for those parameters. Lastly, the dependence of system-level behavior on orientation with respect to gravity was tested by performing dynamic inclination experiments, where the inclination angle was changed every 2 min by a 90-degree increment. These tests reveal an increased relative dependence of the vapor compression cycle to orientation with decreasing mass fluxes, in line with two-phase channel flow research that has generally shown that increasing the flow inertia acts to mitigate various flow instabilities and dependence on orientation. However, inclination testing with longer locking times per angle showed a constant relative dependence of the vapor compression cycle to orientation changes.

Unified Modeling of Pseudo-Slug and Churn Flows for Liquid Holdup and Pressure Gradient Predictions in Pipelines and Wellbores

Summary Pseudo-slug flow is a coherent flow pattern that occurs in horizontal or inclined pipes surrounded by segregated and conventional slug flows. Recent studies have demonstrated that this flow pattern can occupy a large area in the flow pattern map and cannot be simply ignored. Churn flow commonly occurs in upward vertical or slightly deviated wellbores characterized by a chaotic intermittent flow behavior. Pseudo-slug and churn flows are generally considered as two different flow patterns mainly because of their visual differences. However, some recent studies have shown that they share many similarities. There are several hydraulic models for churn flow, and the models for pseudo-slug flow have also emerged in recent years. However, these models only work for a certain inclination angle range, and none work for both flow patterns. This paper proposes a new unified hydraulic model that is applicable for both flow patterns. The liquid holdup prediction is based on the drift-flux model, while the pressure gradient is predicted using a two-fluid model that considers wall frictions from both gas and liquid phases. The new model better captures the effects of gas and liquid flow rates, gas density, liquid viscosity, inclination angle, and pipe diameter on the liquid holdup and pressure gradient compared with other models. Model evaluations show that the new model gives the best predictions compared with other available pseudo-slug or churn models. The new model reduces the total average absolute relative error to 14.0% for the liquid holdup prediction and 19.1% for the pressure gradient prediction.

Decision fusion approach for detecting unknown wafer bin map patterns based on a deep multitask learning model

In semiconductor manufacturing, wafer bin maps (WBMs) present specific defect patterns that provide crucial information for tracking abnormal processes. Thus, it is necessary to correctly classify WBM defects to achieve yield improvements. However, unknown types of defects constantly emerge due to the development of new process technologies and devices, degrading classification performance. Thus, a novel open set recognition (OSR) method that aims to detect unknown defects while correctly classifying known defect types is proposed in this work. The proposed method first extracts the reconstruction errors using an autoencoder and the random network errors using a random network distillation technique. Next, the two types of errors are combined by applying the extreme value theory-based Weibull calibration technique to produce probability scores for unknown detection. Finally, a deep convolutional neural network classifier assigns known classes to the samples determined as known. In the proposed method, multiple networks are interconnected, and we apply a simple sequential multitask learning mechanism to coordinate all networks. Extensive experiments were conducted on a real-world WBM defect dataset, and the results showed that each component proposed in this paper helped improve the unknown detection performance of our approach while minimizing its closed set classification performance loss. As a result, the proposed method outperformed the state-of-the-art OSR methods, achieving area under the receiver operating characteristic curve (AUROC) increases of at least 0.124 for unknown detection cases.

Systematic detection of keratoconus in OCT: corneal and epithelial thickness maps.

To detect keratoconus (KC) only by analyzing the corneal and epithelial map parameters and patterns in optical coherence tomography (OCT). Tertiary care refractive surgery center. Retrospective data collection. Corneal and epithelial thickness maps of normal, manifest, and subclinical keratoconic eyes (according to the Belin-Ambrosio display, Pentacam) were evaluated using spectral-domain OCT (Zeiss Cirrus 5000 HD). A new 2-step decision tree was developed based on previous studies with another OCT device. In the first step, if at least 1 of the 4 independent parameters (pachymetry minimum, pachymetry minimum-median, pachymetry superonasal-inferotemporal, and epithelial superonasal-inferotemporal) overruns the cutoff values, the eye was suspicious for KC. In the second step, if the epithelial map showed concentric thinning and the thinnest point of the cornea and epithelium is coincident, the eye was classified as keratoconic. 172 manifest keratoconic eyes (108 patients), 21 subclinical keratoconic eyes (20 patients), and 172 normal eyes (90 age-matched participants) were included in this study. Step 1 captured 100% of manifest and subclinical keratoconic eyes. Step 2 ruled out all suspicious but normal cases and, falsely, 2 subclinical keratoconic eyes. Our 2-step decision tree reached 100% specificity, 100% sensitivity in manifest KC, and 90.4% sensitivity in subclinical KC. Pachymetric and epithelial map parameters and patterns in OCT can be used in the diagnosis of KC, including subclinical cases, yielding a high level of agreement with the commonly used diagnostic reference, the Belin-Ambrosio display. Further improvements by refining our algorithm and including an automated evaluation in the software are desirable.

Cultural tourism products mapping using geographic information systems in Bekasi

This study aims to identify and analyze the main destinations for cultural tourism in Bekasi City Regency using the Geographic Information System by using mixed methods through spatial geography and a descriptive qualitative approach. The data collection methods are through field surveys with notes, interviews, and documentation. The ArcGIS 10 software is used in order to visualize the data. Furthermore, the qualitative description of the data was served by using the theory of Tourism Products (Attraction, Accessibility, Amenities, and Ancillary). The results of the study indicate that there are four cultural tourism destinations that are the potential to become the representatives of cultural tourism in Bekasi, namely Kranggan Traditional Village, Juang 45 Museum, Hok Lay Temple, and Saung Ranggon Cultural Heritage. The data on each destination is presented in both visual and descriptive form with the purpose to know the distribution of the mapping pattern for the tourism-producing supporting facilities at the attraction and can then be used as an of providing information, data updates, and references to accommodate the developments and policies around the area in order to improve the quality of the tourist experiences while visiting.

Mapping of Gradient Patterns Generated with Helmholtz Coils for Localized Magnetic Fluid Hyperthermia

Magnetic fluid hyperthermia (MFH) is a new generation cancer treatment method under development. One of the challenges that arise in the practical applications of MFH is the limited control of magnetic nanoparticles (MNP). In order to overcome this problem, new approaches are being investigated in MFH tests. Localization of MNP oscillations can be achieved through static magnetic field-free region (FFR) and static magnetic field (SMF) gradients generated by permanent magnets or electromagnets. In this study, Helmholtz coils were used as SMF source to generate gradient patterns (GPs). Finite element method simulation was used to predict GPs that would emerge in the study area. An experiment platform was produced in which the GP would be generated with parametric current changes. Measurements were taken when source currents were (1.1, 1.1 ), (2.2, 2.2), (4.4, 4.4) and (2.2, -2.2) A, respectively. It was observed that FFR form could be manipulated with coil current. The mapping of the GPs and determining FFRs for the use of localized MFH were discussed for the first time in this study. The findings provide insight into which GP is appropriate in which situations in localized MFH.

Improving diversity and quality of adversarial examples in adversarial transformation network

This paper proposes PatternAttack to mitigate two major issues of Adversarial Transformation Network (ATN) including the low diversity and the low quality of adversarial examples. In order to deal with the first issue, this research proposes a stacked convolutional autoencoder based on patterns to generalize ATN. This proposed autoencoder could support different patterns such as all-pixel pattern, object boundary pattern, and class model map pattern. In order to deal with the second issue, this paper presents an algorithm to improve the quality of adversarial examples in terms of \(L_0\)-norm and \(L_2\)-norm. This algorithm employs adversarial pixel ranking heuristics such as JSMA and COI to prioritize adversarial pixels. To demonstrate the advantages of the proposed method, comprehensive experiments have been conducted on the MNIST dataset and the CIFAR-10 dataset. For the first issue, the proposed autoencoder generates diverse adversarial examples. For the second issue, the proposed algorithm significantly improves the quality of adversarial examples. In terms of \(L_0\)-norm, the proposed algorithm decreases from hundreds of adversarial pixels to one adversarial pixel. In terms of \(L_2\)-norm, the proposed algorithm reduces the average distance considerably. These results show that the proposed method can generate high-quality and diverse adversarial examples in practice.

Deep Electrical Resistivity Tomography for Geophysical Investigations: The State of the Art and Future Directions

Electrical Resistivity Tomography (ERT) is a robust and well-consolidated method largely applied in near-surface geophysics. Nevertheless, the mapping of the spatial resistivity patterns of the subsurface at a depth greater than 1 km was performed in just a few cases by the ERT method, called deep ERT (DERT). Since, in many cases, the term DERT was adopted with ambiguity for geoelectrical explorations varying in depth within a range of 0–500 m, the main goal of this review is to clearly define the DERT method, identifying a threshold value in the investigation depth. The study focuses both on the purely methodological aspects (e.g., geoelectrical data processing in low noise-to-signal ratio conditions; tomographic algorithms for data inversion) and on the technological features (e.g., sensor layouts, multi-array systems), envisaging the future directions of the research activity, especially that based on machine learning, for improving the geoelectrical data processing and interpretation. The results of the more significant papers published on this topic in the last 20 years are analyzed and discussed.

Lateral mapping of damage patterns in plasma immersion ion-implanted silicon

Lateral mapping of damage patterns in plasma immersion ion-implanted silicon

Profile of Top 100 Cited in STEM Education for the Last Twenty Years

The research analyzes the top 100 cited publications in STEM education in the last twenty years. The research objectives are to analyze the publication type, year, sources publishing, authorship pattern, institution, country, and keywords pattern and review these top-cited publications using bibliometric analysis. The metadata used in this research is the Scopus database. The study result shows that among these top 100 publications, the most common type of publication is journal articles. Most of these publications were conducted at four-year intervals from 2014 to 2017, with an average citation per paper of 70.75. Belland is recognized as the most productive author, whereas National Research Council has become the institution with the most citations. The most contributed institutions included Purdue University and the University of Minnesota. The USA has led over highly cited publications, followed by Australia and the Netherlands. The research areas in these papers mainly emphasize education, STEM, STEM education, engineering education, and every stem aspect. The review result focus on research on the conceptual framework of STEM integration, STEM-based learning media, challenges to STEM, perspectives on STEM education, and the impact of Covid-19 on STEM education. This research implies finding research novelties about STEM education through the results of mapping and visualization patterns based on keywords that often appear.

"I Didn't Sign Up for This": Perspectives from Persons Living with Dementia and Care Partners on Challenges, Supports, and Opportunities to Add Geriatric Neuropalliative Care to Dementia Specialty Care.

In the United States, dementia specialty centers affiliated with centers of excellence for research hold promise as locations to develop innovative, holistic care in care systems otherwise siloed by discipline or payer. We conducted foundational research to inform development of patient-and family-centered palliative care interventions for dementia specialty centers. We interviewed persons living with dementia (PLWD), current, and former care partners (CP) recruited from a specialty dementia clinic and purposively selected for variation across disease syndrome and stage. A framework method of thematic analysis included coding, analytic matrices, and pattern mapping. 40 participants included 9 PLWD, 16 current CPs, and 15 former CPs of decedents; 48% impacted by Alzheimer's disease dementia. While help from family, support groups and adult day centers, paid caregiving, and sensitive clinical care were invaluable to PLWD, CPs, or both, these supports were insufficient to navigate the extensive challenges. Disease-oriented sources of distress included symptoms, functional impairment and falls, uncertainty and loss, and inaccessible care. Social and relational challenges included constrained personal and professional opportunities. The obligation and toll of giving or receiving caregiving were challenging. Clinical care challenges for PLWD and/or CPs included care fragmentation, insufficient guidance to inform planning and need for expert interdisciplinary clinical care at home. Findings highlight the breadth and gravity of gaps, which surpass the disciplinary focus of either behavioral neurology or palliative care alone. Results can inform the development of novel interventions to add principles of geriatrics and neuropalliative care to dementia care.

Abstract 11738: Epicardial Connections as an Etiology in Recalcitrant Tachyarrhythmias After Left Atrial Ablations in Patients With Persistent Atrial Fibrillation

Introduction: Left atrial radio frequency ablation(RFA) for persistent atrial fibrillation(AF) and left atrial tachycardias(LAT) are often challenging due to the presence of epicardial connections(EC). Hypothesis: Mapping and subsequent ablation of epicardial connections using high density(HD) mapping and activation patterns leads to successful termination of persistent AF and LAT. Methods: We studied 40 patients who were found to have epicardial connections as determined by HD mapping, missing isochrones and activation patterns. All patients underwent antral ablation for pulmonary vein isolation (PVI). LAT were remapped using Advisor HD Grid catheter. Results: At baseline, the mean age and BMI was 74±6.4 and 33.5±5.8 respectively. Out of 40 patients with EC, 21 were associated with the Vein of Marshall (Figure 1), 4 were associated with Septo-pulmonary bundles(figure 2), 6 were associated with the Bachman Bundle(Figure 3) and 9 were associated with Septo-atrial bundles. Acutely, endocardial ablation opposite to the epicardial connection sites achieved success with PVI, Posterior Wall Isolation(PWI) and termination of LAT. Conclusions: EC significantly contributes to the failure of PVI, PWI and the reorganization of LAT. Rigorous mapping of the connecting bundles using HD mapping helps target the ablation sites for successful outcomes.

Abstract 11726: Atrial Arrythmia Recurrence in Patients After Left Atrial Ablation is Associated With Epicardial Connections and Directly Correlated to Reduced Left Ventricular Ejection Fraction

Introduction: Heart Failure with Reduced Ejection Fraction has a positive association with atrial arrhythmia incidence and recurrence. However, this has not been studied in atrial fibrillation (AF) and atrial tachycardia (AT) patients who underwent left atrial radiofrequency ablation(RFA) and were subsequently found to have epicardial connections(EC). Hypothesis: Heart Failure with Reduced Ejection Fraction was associated with an increased recurrence of atrial tachyarrythmias in patients with epicardial connections. Methods: We studied 40 consecutive patients with persistent atrial arrhythmias who underwent RFA for AF and AT at our center. Epicardial connections were determined by high density mapping, missing isochrones and activation patterns. Clinical, echocardiographic and activation mapping pattern characteristics were collected. Results: Forty patients were found to have EC (Table 1). The association of EC and echocardiographic parameters were assessed. Reduced Left Ventricular Ejection Fraction was associated with an increased recurrence of atrial tachyarrhythmias in patients due to epicardial connections((HR:1.25(1.05-1.48)) (Table 2). Conclusions: Reduced Left Ventricular Ejection Fraction is positively correlated with atrial tachyarrythmia recurrence in patients due to epicardial connections.