Characteristics Of Streamers Research Articles

On dynamics of downward-propagating sprite streamers

An approximate approach to estimating characteristics of downward-propagating single positive sprite streamers is presented. Within the framework of this approach, the dependences of streamer radius and velocity on the altitude were obtained. The influence of changes in the altitude of streamer initiation and in the electric field at this altitude on the streamer parameters is considered. Estimates of the optical emission rate are obtained.

What drives viewers’ engagement in travel live streaming: a mixed-methods study from perceived value perspective

Purpose The purpose of this study is to explore the factors influencing viewers’ engagement intention in travel live streaming (TLS) from a perceived value perspective. Design/methodology/approach This study used a mixed-methods approach. In Study 1, 48 semistructured interviews were analyzed based on grounded theory and perceived value theory, and a research framework was established to investigate the impact of viewers’ engagement intentions in TLS. In Study 2, partial least squares structural equation modeling (PLS-SEM) was used to empirically validate survey data from 255 TLS viewers. Findings Through an analysis of the interview content, it was found that the expertise and interaction of the live streamer in TLS as well as the immersion, aesthetics and novelty of the live streaming scene are key influencing factors that affect the engagement of TLS viewers. This finding was confirmed through empirical research. Practical implications This research provides practical suggestions for live streamers, TLS platforms and local government to increase viewer engagement. Specifically, it provides methods and directions for the individual improvement of live streamers, further promotes the development and construction of the platform and underscores the importance of government initiatives in policy support and regulatory framework development. Originality/value This study focuses on the less-researched field of TLS. Using a mixed-methods approach combining interviews and PLS-SEM, this study explores the key factors that affect the engagement of TLS viewers based on the characteristics of live streamers and live streaming scenes.

Tourism live streamers as brand ambassadors: investigating their impact on destination brand value through social exchange theory

Purpose This study aims to identify the key characteristics of tourism live streamers (TLSers) that influence target consumers and examine how these characteristics enhance destination brand value by stimulating consumer emotional engagement and value co-creation behaviors. Design/methodology/approach A questionnaire survey was conducted with 552 respondents who had viewed tourism live streaming in China. The data were analyzed using structural equation modeling. Findings The results revealed that TLSers’ expertise had the strongest influence on consumers and positively affected their attachment, trust, participation and citizenship behaviors and perceived destination brand value. Attractiveness and trustworthiness exerted positive but weaker effects on these variables. Originality/value This study contributes to the theoretical development of live-streaming research by demonstrating the distinct impacts of TLSer characteristics. Furthermore, this study expands the application of the social exchange theory and value co-creation in tourism research.

Simulation on the effect of oxygen concentration on the positive secondary streamer generated in oxygen-rich nitrogen–oxygen mixtures under atmospheric pressure

In this study, we investigated the effect of various O2 concentrations, from 20% to 90%, in nitrogen–oxygen ( N2/O2 ) mixtures on the characteristics of secondary streamers. As oxygen molecules have different molecular characteristics from nitrogen molecules in terms of ionisation threshold and electron attachment property, streamer discharges generated under various nitrogen–oxygen ratios may exhibit differing characteristics such as electron density, electric field, and radical formation. We focused on the changes in these parameters in secondary streamers using simulations. Simulations were first performed under the same conditions as those in previous experiments to compare the results of the ozone production, discharge current, and discharge emission characteristics. To compare the ozone production characteristics, simulated O radicals–the precursor of ozone–were used in the simulation for simplicity. This comparison showed that, although the absolute values of each parameter were different, the simulation exhibited a similar trend in the case of the experimentally obtained oxygen concentration dependence. After the validity of the simulation was verified to some extent via a comparison with the experiment, the results obtained from the simulation were analysed in detail. The results showed that, although the electric field strength in the secondary streamer did not change much as the oxygen concentration increased, the decrease rate of the electron density was greatly accelerated by the electron attachment reaction of oxygen. As a result, many of the electrons had already dissipate during the development of the primary streamer, and few electrons remained when the secondary streamer was formed. This effect suggests that the ratio of the amount of O radicals produced in the primary streamer to that produced in the secondary streamer changes as the oxygen concentration changes.

How the source dynamism of streamers affects purchase intention in live streaming e-commerce: Considering the moderating effect of Chinese consumers’ gender

Streamers, as innovative web influencers and persuaders, have played a crucial role in business marketing success. Extensive research has shown that the characteristics of streamers impact consumers' purchase intentions. However, there is limited research on how the source dynamism of streamers affects consumers' purchase intentions in live streaming. This study uses an experimental approach based on Hovland's persuasion model and the selectivity hypothesis to examine the effects of streamers' source dynamism on purchase intentions and whether the experience resulting from the streamer–consumer interaction is moderated by gender. Findings show that consumers' purchase intention is positively correlated with the source dynamism of streamers and with their perception of para-social interaction and vicarious product experience. In addition, results reveal that gender significantly moderates the relationship between consumers' vicarious product experience and purchase intentions. Females have a stronger vicarious product experience than males and, thus, higher purchase intention when they perceive the high source dynamism of streamers. Lastly, findings highlight the need for brands and suppliers to consider source dynamism when choosing streamers and to allow making different marketing decisions for different consumer genders.

The Simulation of Double Head Streamer Discharge in a 0.5 cm Air Gap

The production and evolution of the double-head streamer discharge in air, as well as the characteristics of positive & negative streamers, were described in this work using a computer simulation method. Streamer discharge in a 0.5 cm air’ gap has been modeled and simulated by the fluid model. Under DC voltage, the model was tested using an axisymmetric plane-to-plane electrode layout in two dimensions. The model was implemented in commercial computation software COMSOL Multiphysics version 6.0 based on finite element method (FEM), in which a time-dependent solver was used. Results indicated that negative streamers travel more quickly than positive ones’, the charged particles (electrons and ions) density have the range of (1013 – 1014) cm−3 in both positive & negative streamer and the breakdown time for the gap (0.5cm) occurs in several nanoseconds.

Repurchase intention in sports brand industry in China: Attributes of live streamers and customer-to-customer interaction of live streaming e-commerce

The rapid growth of live streaming e-commerce is hindered by its high rate of product returns, which poses a challenge to its long-term sustainability. Specifically, clothes shoppers account for 30% of all sales made during live broadcasts. This study aims to evaluate the impact of live streaming e-commerce on repurchase intention in the sports brand industry in China. The paper used quantitative research methods with 398 data collected from consumers of sports brands who were willing to provide information regarding their shopping experience on the live streaming platform. 224 respondents were females (56.3%), and 174 were males (43.7%). The study adopted a questionnaire to collect the data. Partial least squares-structural equation modeling was used to test the correlation between the variables. The results revealed direct and positive effect of consumer trust (β = 0.397, p = 0.000) and perceived value (β = 0.215, p = 0.001) on repurchase intention in live streaming e-commerce. The findings also indicated that both consumer trust and perceived value play a mediating role. In addition, the results supported the assumption that the characteristics of live streamers (β = 0.389, p = 0.000) have a positive impact on consumer trust, and customer-to-customer interaction (β = 0.678, p = 0.000) has a significant impact on perceived value. Finally, sports brands are advised to optimize live streaming platforms to better meet consumers’ needs. Acknowledgment The authors acknowledge Universiti Utara Malaysia (UUM) that supported this study.

Experimental Study and 3-D Modeling of Positive Streamer Discharges Under the Effect of Humidity

The research on streamer discharges not only provides support for insulation design of high-voltage power transmission systems, but also lays a theoretical foundation for lightning discharges. The macroscopic parameters of streamer discharges have been investigated, but there is a lack of analysis on the development and branching characteristics of streamers under the effect of humidity. Besides, different types of models have been built to simulate streamer propagation. However, there are few 3D models which simulate branching process of multiple streamers at different humidity. In this work, a discharge experimental platform with controllable environmental parameters has been built. The effect of the humidity of 4.5~19.1 g/m <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> on streamer propagation and branching has been experimentally studied. Then the 3D “discharge tree” model of collective streamers is improved, in which the streamer branching incorporates the photoionization in humid air. Furthermore, we compare the results of the 3D simulation model with the experimental data. Through the simulation model, the streamer parameters such as line charge density and electric field distribution are obtained. The results show that the electric field of streamer channels are larger when the humidity is higher, but the propagation velocities are reduced. The humidity has limited effect on the streamer branching ratio.

Streamer and Breakdown Characteristics of Transformer Liquids in Moderately Uniform Fields Under Negative Lightning Impulse

The identification of transition field factor boundary between streamer initiation dominated breakdown and streamer propagation dominated breakdown is important for understanding the breakdown mechanisms of transformer liquids and for the transformer insulation design in practice. Most previous studies focused on either very divergent field or nearly uniform field. This paper reports on breakdown voltage tests with three transformer liquids in moderately-uniform fields. The results show that the transition field factor boundary between streamer initiation dominated breakdown and streamer propagation dominated breakdown under negative lightning impulse is liquid dependent. It is 9.6 for a mineral oil, 7.3 for a GTL oil, and 42.0 for a synthetic ester. The difference of the transition field factor boundary helps explain the observed breakdown voltage distinction among the three transformer liquids. In addition, the characteristics of negative streamers leading to breakdown were also investigated in the moderately-uniform fields. Streamer mode transitions with gap distance were observed and clarified, which is from 1 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">st</sup> mode streamer to 2 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">nd</sup> mode streamer in both the mineral oil and GTL oil, while it is the 2 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">nd</sup> mode streamer to fast streamer in the synthetic ester.

How do virtual streamers affect purchase intention in the live streaming context? A presence perspective

The rise of live streaming commerce has attracted attention from scholars and practitioners as a new opportunity to reach consumers. However, few studies have focused on the role of virtual streamers in this context. Based on the stimulus organism response framework, we explore the impact of three characteristics of virtual streamers—likeability, animacy, and responsiveness—on social presence, telepresence, and purchase intention. We use partial least squares structural equation modeling analysis with online survey data from 378 consumers concerning their experiences of viewing virtual streamers. The findings indicate that likeability, animacy, and responsiveness enhance social presence and telepresence, which then promote purchase intention. Likeability and responsiveness directly increase purchase intention, but animacy does not. Multi-group analysis reveals differences between the effects of humanoid and zoonotic virtual streamers on social presence and telepresence. These results shed light on the role of virtual streamer characteristics and contribute to the literature on live streaming commerce, presence, and virtual humans.

The Research on the Characteristics of Chinese Game Virtual Streamers

With the development of the metaverse, many activities have been infiltrated into various virtual interactive experiences. In the widespread live-streaming industry, the virtual anchors who stream behind various animated avatars are favored by a majority of young people. This paper summarizes five characteristics of Chinese game virtual streaming through observations on Bilibili live streaming platform and social media such as Weibo, TikTok and Little Red Book. The author believes that Chinese game virtual streamers have strong role-playing quality, a variety of live games content, humor, versatility and the ability to follow the latest trends. Through these characteristics, they can enrich the live content to attract more audience attention, also strengthen the interaction with the audience and meet the needs of the audience to a greater extent, thus promoting the development of the virtual streaming industry. The analysis of the characteristics of game virtual streamers can make the streamers better improve and strengthen their own advantages and expand the audience group, as well as enable the audience to have a deep understanding of the virtual streamers, which encourages a more appropriate and rational virtual stream watching experience.

Discharge characteristics of positive and negative polarity streamers with submillimeter gap based on fractal theory

In order to study the characteristics of streamer discharge in sub-millimeter gap, an experimental system and an image acquisition system of positive and negative polarity streamer discharge in the gap of 100–500 μm at atmospheric pressure are built, and the initial breakdown voltages and breakdown images of positive and negative polarity streamer discharge in a gap range of 100–500 μm are collected, and the fractal dimension of the experimental discharge images is calculated by Matlab. The experimental analysis shows that the air breakdown discharge in the gap range of 100–500 μm still conforms to the stream theory, and the polarity effect between the breakdown voltage of positive and negative streamers and the fractal dimension of the discharge image is obvious. The influence of space charge and photoionization on the meandering degree and coverage of the discharge channel in stream theory increase with the increase of the gap, and jump at 300 μm. The fractal simulation of positive and negative streamer discharge with a gap of 500 μm is established by using WZ (Wiesmann-Zeller) model based on fractal theory in Matlab. It is found that the development probability index &lt;i&gt;η&lt;/i&gt; is inversely proportional to the fractal dimension, and that the &lt;i&gt;η&lt;/i&gt; is smaller in positive streamer than in negative streamer under the same discharge condition.

Production of runaway electrons and x-rays during streamer inception phase

Streamers play a key role in the formation and propagation of lightning channels. In nature streamers rarely appear alone. Their ensemble behavior is very complex and challenging to describe. For instance, the intricate dynamics within the streamer zone of negative lightning leaders give rise to space stems, which help advance the stepped-leader. Another example is how the increasing morphological complexity of sprites can lead to higher sprite current and greater energy deposition in the mesosphere. Insights into the complex dynamics of a streamer corona can be obtained from laboratory experiments that allow us to control the conditions of streamer formation. Based on simultaneous nanosecond-temporal-resolution photography, and measurements of voltage, current, and x-ray emissions, we report the characteristics of negative laboratory streamers in 88 kPa of atmosphere. The streamers are produced at peak voltages of 62.2 ± 3.8 kV in a point-to-plane discharge gap of 6 cm. While all discharges were driven to the same peak voltage, the discharges occurred at different stages of the relatively slow voltage rise (177 ns), allowing us to study discharge properties as a function of onset voltage. The onset voltage ranged between 24 and 67 kV, but x-ray emissions were observed to only occur above 53 kV, with x-ray burst energies scaling quadratically with voltage. The average delay between the current pulse and x-ray emission was found to be 3.5 ± 0.5 ns, indicating that runaway electrons are produced during the streamer inception phase or no later than the transition stage, when the inception cloud is breaking into streamer filaments. During this short time span, runaway electrons can traverse the gap, hit the ground plate and produce bremsstrahlung x-ray photons. However, streamers themselves cannot traverse more than 3.5 mm across the gap, which supports the idea that runaway electron production is not associated to streamer connection to the ground electrode.

Characteristics and roles of streamers in e-commerce live streaming

ABSTRACT Streamers are the individuals at the core of e-commerce live streaming (ELS), which is a successful influencer marketing strategy. However, a systematic profile of ELS streamers is lacking. This study aims to investigate the roles and characteristics of ELS streamers, as well as their matching relationships, by applying the grounded theory method to analyze semi-structured interviews of 96 consumers. Eight characteristics of ELS streamers (expertise, attractiveness, credibility, interactivity, popularity, price support, affinity, and responsiveness) are identified and further classified into four roles (opinion leader, spokesperson, interactive friend, and salesperson). This study is the first to create a role set for ELS streamers and the first to systematically elucidate the roles of ELS streamers and their corresponding characteristics. It not only supplements e-commerce, influencer marketing, and role theory research by identifying new characteristics and roles of ELS streamers, but it also provides a clear framework practitioners can use to train streamers.

An inventive multi-scale, multiphysics modeling approach and comparative analysis of distinctive features of planar ionization waves in air: I. Negative streamers

A multiscale-multiphysics model of two different patterns of negative discharge (droplets and branches) based on the well-known electro-hydrodynamic equations in a two-dimensional non-axisymmetric configuration is developed to investigate the main features of the negative discharge (e.g. bifurcation, stochastic branching, and evolution of all charged particles including positive and negative ions and electrons). We discuss the challenges behind the finite-element-based streamer models and illustrate the robustness and efficiency of introduced three different meshing techniques via coupled fixed and adaptively refined meshes in terms of the accuracy of results and computational burden. The capability of the model in representing an outstanding spatial resolution of the streamer propagation and its stages is demonstrated under both uniform and non-uniform electric fields. A further required extension of the presented model for the representation of the positive streamer is presented in part II of this series paper. Also, in this part, the distinctive characteristics of both positive and negative streamers are presented, and the different features achieved from the model are thoroughly discussed and compared with the prior experimental results.

Understanding Characteristics of Popular Streamers on Live Streaming Platforms: Evidence from Twitch.tv

Live streaming platforms such as Twitch and Periscope have become some of the most popular synchronous social networking services. To attract viewers, streamers are motivated to broadcast exciting video content while actively interacting with viewers. The emerging stream of research on the live streaming community has examined streamers’ motivations and how the viewers react to streamers. However, few studies have focused on understanding the characteristics of popular streamers. Popular streamers create tremendous business value for social media influencer investors, as they have high potential to create persuasive advertisements and endorsements for firms by promoting their products and services. We aim at examining the key characteristics associated with streamers’ viewer base, namely their personality, professionalism, and streaming affordance. Based on text mining and analyses of video content, our results show: (1) certain personality traits (such as openness) are negatively associated with both cumulative and current popularity, (2) professional players are more likely to attract a larger viewer base, and (3) social affordance, including profile building affordance, social connectivity, and social interactivity, is positively associated with both cumulative and current popularity. Our results provide useful insights into measuring and evaluating streamers’ popularity, which can, in turn, generate actionable strategies for social media influencer investors and platform operators.

Thermal Damage Process and Failure Mechanism of Epoxy/SF6 Composite Insulation Subjected to Arc Ablation

In this work, the effects of arc ablation on the surface of epoxy (EP) in EP/SF <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</sub> composite insulation are analyzed. Based on the results, the characteristics of streamers on the surface of EP is captured by a photomultiplier array and the failure mechanism of the EP is studied. The results show that the arc heat flow applied to the EP/SF <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</sub> interface can lead to the decomposition of EP molecular chains and degradation of the SF <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</sub> . The pyrolysis products re-couple to generate complex carbides and pyrolysis gases, resulting in severe irregular carbonization on the EP surface and the increase in surface conductivity. When an external electric field is applied, a large quantity of photons will accumulate in the carbonization region on the EP surface and this gives rise to the surface streamer and thereby greatly decreases the surface electrical strength of EP/SF <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</sub> composite insulation.

Determination of Additional Tension in Towed Streamer Cable Triggered by Collision with Underwater Moving Object

Abstract The paper deals with issues connected with the behaviour of a streamer cable towed by a survey seismic vessel when the cable undergoes a strike triggered by collision with an underwater moving object. The consequences of such collisions may be both threat to the life of marine animals or damage to underwater units and large economic losses suffered by vessel owners. The risk of such collisions has increased over the last years as a result of increased offshore seismic survey operations. Therefore, a towed streamer should be very robust. To assure its robustness, we should know the deformation mechanism of a single streamer cable. This in turn requires the development of an appropriate mathematical model of such a phenomenon. In particular, the paper presents the characteristics of seismic survey vessels and streamers; an analysis of collisions that have occurred in the past; a statement of the problem, and a computer-aided system supporting simulation of the cable behaviour. To obtain all the necessary design parameters regarding the deformation mechanism of a streamer cable, we set up a dedicated computer-aided system that supports their calculation.

A computational study of negative surface discharges: Characteristics of surface streamers and surface charges

We investigate the dynamics of negative surface discharges in air through numerical simulations with a 2D fluid model. A geometry consisting of a flat dielectric embedded between parallel-plate electrodes is used. Compared to negative streamers in bulk gas, negative surface streamers are observed to have a higher electron density, a higher electric field and higher propagation velocity. On the other hand, their maximum electric field and velocity are lower than for positive surface streamers. In our simulations, negative surface streamers are slower for larger relative permittivity. Negative charge accumulates on a dielectric surface when a negative streamer propagates along it, which can lead to a high electric field inside the dielectric. If we initially put negative surface charge on the dielectric, the growth of negative surface discharges is delayed or inhibited. Positive surface charge has the opposite effect.

Relationship between the Electrical Characteristics of Molecules and Fast Streamers in Ester Insulation Oil.

The effects of C=C, ester and β-H groups on the ionization potential (IP) and electron affinity (EA) of molecules in natural ester insulation oil were investigated by density functional theory (DFT). The major contribution to the highest occupied molecular orbital (HOMO) comes from the carbon atoms adjacent to C=C. Thus, the IPs of triglycerides decrease as the number of C=C double bonds increases. The C=C in alkanes may also lower the IP. However, the β-H in triglycerides has little effect on the IP, and C=C and β-H have only a small effect on the EAs of the triglycerides because of the major contributions of atoms near the ester group in triglycerides to the lowest unoccupied molecular orbital (LUMO). This study calculated the IPs of 53 kinds of molecules in FR3, which are significantly lower compared with those of molecules in mineral oil (MO) and trimethylolpropane triester without C=C. However, the lightning impulse breakdown voltage (LI Vb) of trimethylolpropane triester is still significantly lower than that of MO at the large gap. Therefore, the transition from slow to fast streamers under low lighting impulse voltage is determined by the ester group rather than by C=C and β-H. The ester group may attract more electrons, impacting itself more compared to alkane in MO and facilitating the transition from slow to fast streamers.