Interdimensional optical isospectrality inspired by graph networks

A network picture has been applied to various physical and biological systems to understand their governing mechanisms intuitively. Utilizing discretization schemes, both electrical and optical materials can also be interpreted as abstract 'graph' networks composed of couplings (edges) between local elements (vertices), which define the correlation between material structures and wave flows. Nonetheless, the fertile structural degrees of freedom in graph theory have not been fully exploited in physics owing to the suppressed long-range interaction between far-off elements. Here, by exploiting the mathematical similarity between Hamiltonians in different dimensions, we propose the design of reduced-dimensional optical structures that perfectly preserve the level statistics of disordered graph networks with significant long-range coupling. We show that the disorder-induced removal of the level degeneracy in high-degree networks allows their isospectral projection to one-dimensional structures without any disconnection. This inter-dimensional isospectrality between high- and low-degree graph-like structures enables the ultimate simplification of broadband multilevel devices, from three- to one-dimensional structures

The Impact of CRM on Firm- andRelationship-Level Performance in Distributed Networks

This paper develops and empirically tests a model to evaluate a manufacturer\u27s strategy which provides customer relationship management (CRM) technology to its exclusive retailers. The impact of the strategy on manufacturer-retailer relationship quality is also examined. The research objectives are (1) to identify and test factors that promote active implementation of CRM technology among small retail organizations; (2) to determine whether our expanded concept of CRM implementation that integrates customer information management activities and relationship marketing activities explains CRM performance better; and (3) to investigate whether a manufacturer\u27s support contributes to manufacturer-retailer relationship quality. Statistical analysis shows that the model provides an adequate fit to the data. The retailer\u27s perception of the importance of customer information, manufacturer support, and trade area competitiveness significantly impacts the intensity of CRM implementation by small retailers. CRM implementation intensity positively influences the performance outcomes of CRM, which in turn greatly improves the quality of the manufacturer-retailer relationship. Different from our expectation, supporting retailers with CRM technology did not directly impact the manufacturer-retailer relationship quality. The ease of use of the CRM system also did not influence CRM implementation intensity significantly. The implications of these results and their importance for successful CRM implementation are discussed

PU GNN: Chargeback Fraud Detection in P2E MMORPGs via Graph Attention Networks with Imbalanced PU Labels

The recent advent of play-to-earn (P2E) systems in massively multiplayer online role-playing games (MMORPGs) has made in-game goods interchangeable with real-world values more than ever before. The goods in the P2E MMORPGs can be directly exchanged with cryptocurrencies such as Bitcoin, Ethereum, or Klaytn via blockchain networks. Unlike traditional in-game goods, once they had been written to the blockchains, P2E goods cannot be restored by the game operation teams even with chargeback fraud such as payment fraud, cancellation, or refund. To tackle the problem, we propose a novel chargeback fraud prediction method, PU GNN, which leverages graph attention networks with PU loss to capture both the players' in-game behavior with P2E token transaction patterns. With the adoption of modified GraphSMOTE, the proposed model handles the imbalanced distribution of labels in chargeback fraud datasets. The conducted experiments on three real-world P2E MMORPG datasets demonstrate that PU GNN achieves superior performances over previously suggested methods.Comment: Under Review, Industry Trac

DIFFERENCES IN TRUNK ANGLES THROUGH DIFFERENT SHOOTING DIRECTIONS IN WATER POLO PENALTY SHOOTING

The purpose of this study was to investigate three-dimensionally the shooter’s trunk motion through 4 different shooting directions. Ten Korean national level water polo players who are right-handed were participated in this study (age, 21.60±3.20 years; weight, 86.30±8.86 kg; height, 1.83±0.05 m). To analyze the shooter’s trunk motion among different target, a three-dimensional motion analysis with six video cameras was performed.The analysis events were coking when the trunk was externally rotated maximally and release moment. A one-way ANOVA with repeated measure was performed as main statistical tests and Bonferroni correction was used as a post-hoc test. The results showed that there was statistically significant difference in trunk angle between left and right shooting directions. Especially, the posterior leaning and external rotation angles of trunk in cocking moment were bigger in left shooting direction compared to right one (p\u3c.05). These results suggest that goalkeepers predict shooting direction more precisely by identifying the trunk posture at coking moment

KINEMATIC ANALYSIS OF DIVING BACK PIKE SOMERSAULT IN PLATFORM ACCORDING TO PLAYERS’ SKILL LEVEL

The purpose of this study was to investigate the kinematic difference in Back Pike somersault in platform diving according to players‘ skill level and to assist them to improve performances. Ten Korean diving athletes participated in this study and they were divided into skilled group (n=5) and less-skilled group (n=5) and t-test was performed to find the difference at the moment of take-off between groups. The results showed that the hip extension angle was greater and the extension velocity of knee and hip joints were faster in skilled group compared to less-skilled group. It is recommended, therefore that the flexibility training of hip joint and muscle strength training to enhance extension velocity of knee and hip joints are needed