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Article
Publication date: 19 December 2022

Keshan (Sara) Wei

In the present world of constant connectivity, the barrage system, as a system of real-time dynamic comments coupled with video content, has become a popular interactive system…

Abstract

Purpose

In the present world of constant connectivity, the barrage system, as a system of real-time dynamic comments coupled with video content, has become a popular interactive system technology for video sharing platforms. This study investigates how barrage system fluctuation characteristics, namely, barrage fluctuation amplitude and frequency, impact user interaction.

Design/methodology/approach

The research model was estimated with a fixed-effects regression applied to a longitudinal panel dataset collected from one of the most popular video sharing platforms in China (Bilibili.com).

Findings

Barrage fluctuation frequency has positive effects on users' real-time (synchronous) barrage interaction and the traditional (asynchronous) comment interaction. Barrage fluctuation amplitude has a positive effect on users' real-time (synchronous) barrage interaction but a negative effect on traditional (asynchronous) comment interaction. In addition, the interaction effects of the barrage fluctuation frequency and the barrage fluctuation amplitude on user interaction show adverse effects.

Originality/value

The results revealed the impact of different barrage fluctuation characteristics on different forms of interaction and provide important theoretical contributions and managerial implications in terms of user interaction on video sharing platforms.

Details

Journal of Research in Interactive Marketing, vol. 17 no. 4
Type: Research Article
ISSN: 2040-7122

Keywords

Article
Publication date: 3 January 2023

Kuok Kei Law, Matthew C-H Yeung and Jimmy H-T Chan

This paper aims to examine the effect of short-term performance fluctuations on long-term performance of football clubs.

Abstract

Purpose

This paper aims to examine the effect of short-term performance fluctuations on long-term performance of football clubs.

Design/methodology/approach

This study did not develop any hypothesis for statistical testing. Instead, a database composing of 24 seasons of English Premier Club clubs’ performance was used to analyse for temporal fluctuations of club performance and examined whether such fluctuations would be substantiated in the long run.

Findings

Findings showed that club performance exhibited a non-unit root nature, which in turn suggested that clubs’ long-term performance was only temporally affected by short-term performance fluctuations, leading to the evidence that club performance tended to return to the club’s long-run equilibrium after experiencing temporary high or low positions.

Originality/value

Findings of this paper provide important information regarding the cost-benefit implications of the reactions of the club management to boost or rectify short-term performance fluctuations by, for example, replacing the club manager or head coach.

Details

Team Performance Management: An International Journal, vol. 29 no. 1/2
Type: Research Article
ISSN: 1352-7592

Keywords

Article
Publication date: 24 June 2021

Zaiyang Xie, Liang Qu, Runhui Lin and Qiutong Guo

Environmental regulation is in a continuous state of intense change and modification amid the long-term tensions between environmental protection and economic growth. In this…

Abstract

Purpose

Environmental regulation is in a continuous state of intense change and modification amid the long-term tensions between environmental protection and economic growth. In this article, the authors creatively investigate how fluctuations of environmental regulation influence a nation's economic growth while also examining the mediating effect of technological innovation.

Design/methodology/approach

Using sample data of 36 Organisation for Economic Co-operation and Development (OECD) countries from 2013 to 2018, environmental regulation is differentiated in two aspects of formal environmental regulation (FER) and informal environmental regulation (IER) and analyzed to assess the effects of regulatory fluctuations on investment and technological innovation.

Findings

The research results demonstrate that both FER fluctuation and IER fluctuation exert a significant negative impact on economic growth. These two fluctuations in environmental regulation increase uncertainty and unpredictable risks for corporations and investors, significantly stifling the willingness to contribute to innovation activities and leading to a diminished level of innovation. Technological innovation is revealed to have a mediating influence on the relationship of environmental regulation fluctuation to economic growth.

Originality/value

These findings enrich the research on the impact of environmental regulation from a dynamic, multinational perspective, contributing to the literature by exploring the relationships between environmental regulation fluctuation, technological innovation and economic growth at the OECD-country level.

Details

Journal of Enterprise Information Management, vol. 35 no. 4/5
Type: Research Article
ISSN: 1741-0398

Keywords

Article
Publication date: 19 August 2021

Morteza Ghaseminezhad, Aref Doroudi, Seyed Hossein Hosseinian and Alireza Jalilian

Voltage fluctuation (flicker) is a power quality disturbance that can produce several undesirable effects on industrial equipment. This paper aims to present the methodology and…

Abstract

Purpose

Voltage fluctuation (flicker) is a power quality disturbance that can produce several undesirable effects on industrial equipment. This paper aims to present the methodology and results of investigations undertaken to examine the speed and torque of an induction motor (IM) under voltage fluctuation conditions.

Design/methodology/approach

The IM response to different characteristics of voltage fluctuations is presented. It will be shown that under a special condition the IM torque can even reach two times the rated torque. To show how this occurs, a qualitative discussion is given on the motor response by linearized equations.

Findings

The small-signal analysis was used to determine the frequency which leads to maximum speed fluctuations. It was shown that, if the motor is excited with a modulation frequency (resonant frequency) which is one of its natural frequencies (modes), the mode will act as a fluctuating amplifier and greatly increase the amplitude of torque and speed fluctuations. Sensitivity analysis is also carried out to evaluate the influence of motor parameters on the resonance frequency. The results show that the resonance frequency is not affected at all by the changes in magnetizing reactance. This has been shown that magnetic saturation does not have any impact on the resonance frequency. The most effective parameters are rotor and stator resistances.

Originality/value

With the increasing popularity and use of arc furnace loads in the metallurgy industry and due to the wide application of large IMs in the industry, it is possible that the frequency of torque pulsation locates near a natural frequency and then will create an oscillation with a large magnitude, potentially leading to accelerated fatigue or severe damage of shaft. However, if this phenomenon occurs in industries, the resonance frequency must be filtered from the input voltage. Experimental results on a 1.1 kW, 380 V, 50 Hz, 2 pole IM are used to validate the accuracy of simulation results.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. 40 no. 4
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 12 June 2017

Lei Cao, Yexiang Xiao, Zhengwei Wang, Yongyao Luo and Xiaoran Zhao

The purpose of this paper is to study the pressure fluctuation characteristics in the sidewall gaps of a centrifugal dredging pump in detail and discover the excitation sources.

Abstract

Purpose

The purpose of this paper is to study the pressure fluctuation characteristics in the sidewall gaps of a centrifugal dredging pump in detail and discover the excitation sources.

Design/methodology/approach

An unsteady numerical simulation with shear–stress transport–scale-adaptive simulation (SAS-SST) model was conducted for a centrifugal pump considering the sidewall gaps. The numerical codes were validated by a model test carried out in China Water Resources Beifang Investigation, Design and Research Co., Ltd. Fast Fourier transform was used to obtain the frequency components of the pressure fluctuation.

Findings

Pressure fluctuation characteristics inside the pump were analyzed for a condition near the design point. In the sidewall gaps, the circumferential, radial and axial distribution of the pressure fluctuation amplitude follow different laws. The non-axisymmetrical distribution of pressure fluctuation in the sidewall gaps shows that the unsteady flow in the volute casing which has a non-axisymmetrical geometry imposes an evident effect on the flow field in the sidewall gaps and the interaction between the main flow and the clearance flow cannot be neglected. There are several frequency components appearing as the dominant frequencies at different locations in the sidewall gaps, but the relatively stronger pressure fluctuations are all dominated by the rotating frequency. It indicates that the rotating impeller, which originally makes the shrouds rotate, is the primarily excitation source of the pressure fluctuations in the sidewall gaps.

Originality/value

The pressure fluctuation characteristics in the sidewall gaps of centrifugal pumps were first comprehensively analyzed. Unsteady flows in the sidewall gaps should be considered during the design and operation of centrifugal pumps.

Details

Engineering Computations, vol. 34 no. 4
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 1 October 2001

Wouter Mettrop and Paul Nieuwenhuysen

An empirical investigation of the consistency of retrieval through Internet search engines is reported. Thirteen engines are evaluated: AltaVista, EuroFerret, Excite, HotBot…

Abstract

An empirical investigation of the consistency of retrieval through Internet search engines is reported. Thirteen engines are evaluated: AltaVista, EuroFerret, Excite, HotBot, InfoSeek, Lycos, MSN, NorthernLight, Snap, WebCrawler and three national Dutch engines: Ilse, Search.nl and Vindex. The focus is on a characteristics related to size: the degree of consistency to which an engine retrieves documents. Does an engine always present the same relevant documents that are, or were, available in its databases? We observed and identified three types of fluctuations in the result sets of several kinds of searches, many of them significant. These should be taken into account by users who apply an Internet search engine, for instance to retrieve as many relevant documents as possible, or to retrieve a document that was already found in a previous search, or to perform scientometric/bibliometric measurements. The fluctuations should also be considered as a complication of other research on the behaviour and performance of Internet search engines. In conclusion: in view of the increasing importance of the Internet as a publication/communication medium, the fluctuations in the result sets of Internet search engines can no longer be neglected.

Details

Journal of Documentation, vol. 57 no. 5
Type: Research Article
ISSN: 0022-0418

Keywords

Book part
Publication date: 23 July 2016

Daniele Besomi

This chapter enquires into the contribution of two British writers, Herbert Somerton Foxwell and Henry Riverdale Grenfell, who elaborated upon the hints provided by Jevons towards…

Abstract

This chapter enquires into the contribution of two British writers, Herbert Somerton Foxwell and Henry Riverdale Grenfell, who elaborated upon the hints provided by Jevons towards a description of long waves in the oscillations of prices. Writing two decades after Jevons, they witnessed the era of high prices turning into the great depression of the last quarter of the nineteenth century, the causes of which they saw in the end of bimetallism. Not only did they take up Jevons’s specific explanation of the long fluctuations, but they also based their discussion upon graphical representation of data and incorporated in their treatment a specific trait (the superposition principle) of the ‘waves’ metaphor emphasized by the Manchester statisticians in the 1850s and 1860s. Their contribution is also interesting for their understanding of crises versus depressions at the time of the emergence of the interpretation of oscillations as a cycle, which they have only partially grasped – as distinct from the approach of later long wave theorists.

Details

Research in the History of Economic Thought and Methodology
Type: Book
ISBN: 978-1-78560-960-2

Keywords

Abstract

Details

Energy Economics
Type: Book
ISBN: 978-1-83867-294-2

Open Access
Article
Publication date: 17 January 2023

Xing Ying

The purpose of this paper investigates dynamic ease distributions of clothes at bust and waist lines with different body surface angle by using a Qualisys three-dimensional motion…

Abstract

Purpose

The purpose of this paper investigates dynamic ease distributions of clothes at bust and waist lines with different body surface angle by using a Qualisys three-dimensional motion capture system (3DMCS).

Design/methodology/approach

The current method first obtain the specific markers of participants and their clothes along the bust and waist lines through 3DMCS, then using the least square method and four piecewise polynomial fitting participants and their clothes' bust and waist curves. The coordinates of the markers were tracked by the 3DMCS, while the participants under different body surface angle walked on a treadmill calculated the distances of markers coordinates to the participants' bust and waist curves. Finally, the data of samples were analyzed. It was found that the dynamic ease distributions showed different patterns at different body surface angle.

Findings

The results revealed the bust convex angle is 26.53 degrees (Specification:X3) and back slope angle is 13.96 degrees (Specification: Y1), the fluctuation of participant ease distributions on bust section was most obvious, and the maximum fluctuation value was ±20 mm and ±25 mm. The ease distributions of participant waist section fluctuated most obviously when the bust convex angle is 28.10 degrees (Specification: X5) and the back slope angle is 13.96 degrees (Specification: Y1), and the maximum fluctuation was ±30 mm and ±20 mm. The bust convex angle has the greatest influence on 1# garment, and the back slope angle has the greatest influence on 2# garment.

Originality/value

Currently, there is little information in the literature about dynamic ease distributions of garment on a different body types. This paper takes different body surface angles as the research objects to analyze the ease distributions of different clothes, the conclusion can provide reference data for 3D garment modeling and improve the authenticity of virtual garment fitting.

Details

International Journal of Clothing Science and Technology, vol. 35 no. 2
Type: Research Article
ISSN: 0955-6222

Keywords

Content available
Article
Publication date: 12 January 2022

Jihong Chen, Renjie Zhao, Wenjing Xiong, Zheng Wan, Lang Xu and Weipan Zhang

The paper aims to identify the contributors to freight rate fluctuations in the Suezmax tanker market; this study selected the refinery output, crude oil price, one-year charter…

Abstract

Purpose

The paper aims to identify the contributors to freight rate fluctuations in the Suezmax tanker market; this study selected the refinery output, crude oil price, one-year charter rate and fleet development as the main influencing factors for the market analysis.

Design/methodology/approach

The paper used the vector error correction model to evaluate the degree of impact of each influencing factor on Suezmax tanker freight rates, as well as the interplay between these factors.

Findings

The conclusion and results were tested using the 20-year data from 1999 to 2019, and the methodology and theory of this paper were proved to be effective. Results of this study provide effective reference for scholars to find the law of fluctuations in Suezmax tanker freight rates.

Originality/value

This paper provides a decision-making support tool for tanker operators to cope with fluctuation risks in the tanker shipping market.

Details

Maritime Business Review, vol. 8 no. 1
Type: Research Article
ISSN: 2397-3757

Keywords

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