ANONYMITY AND PERCEIVED NETWORK-STRUCTURE: A MODEL OF VIRTUAL COMMUNITY KNOWLEDGE INTENTIONS

This study investigates the underlying motivational factors with regard to the knowledge exchange intentions (intention to obtain and provide knowledge) in virtual community contexts. Perceived virtual network structure, namely, virtual network connectivity and virtual network closeness are suggested as the important antecedents of knowledge sharing intentions in the context of virtual knowledge exchange community. Anonymity, one of the unique characteristics of virtual community but controversial due to its multi-facet effects, is considered in a structural model as a factor having impacts on a virtual network structure

Analysis of the semantic network of post-traumatic stress disorder using Korean social big data

Introduction: In this study, we wanted to examine how post-traumatic stress disorder was discussed in Korean newspaper articles with semantic network analysis suitable for unstructured big data analysis. Methods: This study analyzed 11,304 articles related to post-traumatic stress reported by four major Korean newspapers for three years from July 30, 2017, to July 30, 2020. R 3.6.2 program was used to calculate TF and TF-IDF values, and UCINET 6.0 and interlocked NetDraw was used for DC, EC, and CONCOR values. Results: As a result of deriving 50 major keywords with high TF-IDF values ​​in newspaper articles related to a post-traumatic stress disorder, TF-IDF values were high in the order of 'sick leave', 'solitary confinement', 'detention center', 'standing order', and 'prisoner'. As a result of conducting a CONCOR analysis to determine which sub-clusters keywords are classified into, the researcher derived each cluster based on words included: 'PTSD by crops' (cluster 1), 'PTSD by broadcasting accidents' (clusters), 'PTSD by farm livestock accidents' (cluster 3), and 'PTSD by various accidents' (cluster 4). Conclusions Based on the research results, post-traumatic stress disorder needs to be managed nationally. As such, we intend to provide basic data for policy development and intervention programs

Analysis of the Market Structure and Shift-effects in North China Ports

ABSTRACTThis study divides the foreign trade traffic of major North China ports into export and import cargoes for the past 10 years. Then, the concentration ratios and shift effects are analyzed in order to determine their relationships with the ports’ competition structures. Here, the HHI, a BCG matrix analysis, and the shift effects are applied as study methods. The results indicate that the oligopoly market structure of major North China ports has gradually decreased. Furthermore, the concentration ratios of import cargoes are higher than those of export cargoes, indicating that competition to attract import cargoes will intensify. Therefore, the effects of the South Korea–China FTA mean that the competition structures of these ports with regard to export and import cargoes are highly likely to be differentiated further over time

Entangling quantum and classical states of light

Entanglement between quantum and classical objects is of special interest in the context of fundamental studies of quantum mechanics and potential applications to quantum information processing. In quantum optics, single photons are treated as light quanta while coherent states are considered the most classical among all pure states. Recently, entanglement between a single photon and a coherent state in a free-traveling field was identified to be a useful resource for optical quantum information processing. However, it was pointed out to be extremely difficult to generate such states since it requires a clean cross-Kerr nonlinear interaction. Here, we devise and experimentally demonstrate a scheme to generate such hybrid entanglement by implementing a coherent superposition of two distinct quantum operations. The generated states clearly show entanglement between the two different types of states. Our work opens a way to generate hybrid entanglement of a larger size and to develop efficient quantum information processing using such a new type of qubits.Comment: 9 pages, 4 figure

Light Adaptation through Phosphoinositide-Regulated Translocation of Drosophila Visual Arrestin

AbstractPhotoreceptor cells adapt to bright or continuous light, although the molecular mechanisms underlying this phenomenon are incompletely understood. Here, we report a mechanism of light adaptation in Drosophila, which is regulated by phosphoinositides (PIs). We found that light-dependent translocation of arrestin was defective in mutants that disrupt PI metabolism or trafficking. Arrestin bound to PIP3 in vitro, and mutation of this site delayed arrestin shuttling and resulted in defects in the termination of the light response, which is normally accelerated by prior exposure to light. Disruption of the arrestin/PI interaction also suppressed retinal degeneration caused by excessive endocytosis of rhodopsin/arrestin complexes. These findings indicate that light-dependent trafficking of arrestin is regulated by direct interaction with PIs and is required for light adaptation. Since phospholipase C activity is required for activation of Drosophila phototransduction, these data point to a dual role of PIs in phototransduction

Fault-tolerant quantum computation by hybrid qubits with bosonic cat-code and single photons

Hybridizing different degrees of freedom or physical platforms potentially offers various advantages in building scalable quantum architectures. We here introduce a fault-tolerant hybrid quantum computation by taking the advantages of both discrete variable (DV) and continuous variable (CV) systems. Particularly, we define a CV-DV hybrid qubit with bosonic cat-code and single photon, which is implementable in current photonic platforms. By the cat-code encoded in the CV part, the dominant loss errors are readily correctable without multi-qubit encoding, while the logical basis is inherently orthogonal due to the DV part. We design fault-tolerant architectures by concatenating hybrid qubits and an outer DV quantum error correction code such as topological codes, exploring their potential merits in developing scalable quantum computation. We demonstrate by numerical simulations that our scheme is at least an order of magnitude more resource-efficient over all previous proposals in photonic platforms, allowing to achieve a record-high loss threshold among existing CV and hybrid approaches. We discuss its realization not only in all-photonic platforms but also in other hybrid platforms including superconduting and trapped-ion systems, which allows us to find various efficient routes towards fault-tolerant quantum computing.Comment: 21 pages, 8 figure