31 research outputs found
LiveRetro: Visual Analytics for Strategic Retrospect in Livestream E-Commerce
Livestream e-commerce integrates live streaming and online shopping, allowing
viewers to make purchases while watching. However, effective marketing
strategies remain a challenge due to limited empirical research and subjective
biases from the absence of quantitative data. Current tools fail to capture the
interdependence between live performances and feedback. This study identified
computational features, formulated design requirements, and developed
LiveRetro, an interactive visual analytics system. It enables comprehensive
retrospective analysis of livestream e-commerce for streamers, viewers, and
merchandise. LiveRetro employs enhanced visualization and time-series
forecasting models to align performance features and feedback, identifying
influences at channel, merchandise, feature, and segment levels. Through case
studies and expert interviews, the system provides deep insights into the
relationship between live performance and streaming statistics, enabling
efficient strategic analysis from multiple perspectives.Comment: Accepted by IEEE VIS 202
Influence of light illumination on the potential-induced degradation of n-type interdigitated back-contact crystalline Si photovoltaic modules
We investigate the potential-induced degradation (PID) of n-type interdigitated back-contact (IBC) crystalline Si (c-Si) photovoltaic (PV) modules under a negative bias stress and the influence of light illumination on the PID. IBC PV modules show PID characterized by reductions in short-circuit current density (J_) and open-circuit voltage (V_) under negative bias stress, while no fill factor (FF) reduction is observed. The degradation may originate from sodium (Na) introduction into c-Si and resulting enhancement of carrier recombination on the surface of the IBC cells. 1-sun light illumination during the negative-bias PID test results in less severe reductions in J_ and V_. A reduction in an electric field in the surface Si nitride (SiN_x) film due to carrier generation in the SiN_x and resulting increase in its conductivity is one of the possible explanations for the mitigation of the Na-related PID
An Improved CamShift Algorithm for Target Tracking in Video Surveillance
Target tracking in a cluttered environment remains a challenging research topic. The task of target tracking is a key component of video surveillance and monitoring systems. In this paper, we present an improved CamShift algorithm for tracking a target in video sequences in real time. Firstly, a background-weighted histogram which helps to distinguish the target from the background and other targets is introduced. Secondly, the window size is calculated to track the target as its shape and orientation change. Finally, we use a Kalman Filter to avoid being trapped by a local maximum. The introduction of the Kalman Filter also enables track recovery following a total occlusion. Experiments on various video sequences illustrate the proposed algorithm performs better than the original CamShift approach
Influence of Retrogression Time on the Fatigue Crack Growth Behavior of a Modified AA7475 Aluminum Alloy
This paper investigates the effect of retrogression time on the fatigue crack growth of a modified AA7475 aluminum alloy. Tests including tensile strength, fracture toughness, and fatigue limits were performed to understand the changes in properties with different retrogression procedures at 180 °C. The microstructure was characterized using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The findings indicated that as the retrogression time increased, the yield strength decreased from 508 MPa to 461 MPa, whereas the fracture toughness increased from 48 MPa√m to 63.5 MPa√m. The highest fracture toughness of 63.5 MPa√m was seen after 5 h of retrogression. The measured diameter of η’ precipitates increased from 6.13 nm at the retrogression 1 h condition to 6.50 nm at the retrogression 5 h condition. Prolonged retrogression also increased the chance of crack initiation, with slower crack growth rate in the long transverse direction compared to the longitudinal direction. An empirical relationship was established between fracture toughness and the volume fraction of age-hardening precipitates, with increasing number density of precipitates seen with increasing retrogression time
comparative study of real-time multimedia transmission over multi-homing transport protocols
The availability of multimedia applications suitable for deployment using 3G and GPRS networks has led to a requirement for end-to-end quality of service. More efficient mechanisms are needed in order to provide the required end user quality of service i
performance evaluation of distributing real-time video over concurrent multipath
Recent research on Concurrent Multipath Transfer (CMT) and CMT with a Potentially-Failed destination state (CMT-PF) uses the transport layer multi-homing protocol Stream Control Transmission Protocol (SCTP) to increase application throughput by distributing transmitted data across multiple end-to-end paths. This paper investigates and evaluates the performance of CMT with Partial Reliability (CMT-PR) and CMT-PF with Partial Reliability (CMT-PF-PR), novel extensions of SCTP for real-time video distribution. The Evalvid-CMT platform was implemented in the University of Delawares SCTP/CMT ns-2 module to perform emulation experiments in order to compare CMT and CMT-PR, CMT-PF and CMT-PFPR, respectively. The results presented in the paper show how the CMT-PR and CMT-PF-PR outperform CMT and CMT-PF respectively. Consequently the former are suggested as strategies for real-time video concurrent multipath transmissions
analysis of real-time multimedia transmission over pr-sctp with failover detection delay and reliability level differential
The growing availability of different wireless access technologies provides the opportunity for real-time distribution of multimedia content using multi-homing technology. Investigating the behaviors and quality of such applications under heavy network load is necessary. This paper studies the effect of path failure detection threshold and reliability level on Stream Control Transmission Protocol Partial Reliability Extension (PR-SCTP) performance in symmetric and asymmetric path conditions respectively with different path loss rates. The platform Evalvid-SCTP implemented in the University of Delawares SCTP ns-2 module performs the emulation experiment. © 2009 IEEE