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While the number of hybrid journals has increased with the conversion from subscription journals, article processing charges (APCs) have not been examined as frequently as gold open access journals. This study compared the factors affecting APCs for hybrid and gold open access journals by formulating a charge equation.

This study examined the APCs for 1,354 hybrid and gold open access journals in the Springer imprint. Using the ordinary least squares method, it investigated the determinants of charges, including the relationship between subscription prices and APCs for hybrid journals.

The results revealed that the charges set by hybrid journals were higher than those set by gold open access journals by US$1,620, after controlling for other variables. A reason could be the oligopolistic market structure of the leading publishers. Although the publisher imprint set the APCs based on the journal characteristics, the difference in the determinants of the charges between the two journal types may be due to the business models specific to the journal types.

The findings suggested that policymakers must consider the market power of leading publishers to establish a healthy scholarly communication market.

This study examined the relationship between subscription prices and charges for hybrid journals as well as the determinants of charges for both journal types, considering various characteristics of individual journals.

In recent years, researchers have focused a great deal of attention on multirecess hybrid journal bearing systems. The non‐circular journal bearings are widely used in industry on account of their better stability, simplicity, efficiency and low cost. The purpose of this paper is to present a theoretical investigation into the performance of a two‐lobe multirecess hybrid journal bearing system.

The Reynold's equation governing the lubricant flow in the clearance space between the journal and bearing together with restrictor flow equations has been solved using finite element method. The bearing static and dynamic performance characteristics have been presented for the various values of the offset factors (0.75, 1, 1.25 and 1.50) for the hybrid mode of operation of the journal bearing system compensated by capillary and orifice restrictors for the commonly used bearing operating and geometric parameters. The offset of the journal has been accounted for by defining a non‐dimensional factor called offset factor delta.

The numerically simulated results indicate that a two‐lobe four recessed hybrid journal bearing provides a better performance than the corresponding similar circular recessed journal bearing system. The study further reveals that in order to get an improved performance of a two‐lobe four recessed journal bearing, a proper selection of bearing offset factors along with type of restrictor (capillary or orifice) is essential.

The results presented in this paper are useful for bearing designers.

There are different opinions about the quality and reputation of publications. Given that one of the ways to analyze the quality of journals and articles is citation indicators, the purpose of this paper is to compare the citation indicators of open access (OA), full subscription and hybrid journals and articles based on the Scopus in the field of library and information science (LIS) for a period of ten years (2004-2013).

The research population is all LIS journals and articles in LIS hybrid journals in Scopus. The data related to citation indicators (number of received citations, two years’ impact, Citescore [IPP] and H-index) were extracted from Scopus, Journal Metrics and SCImago and analyzed using descriptive and analytical statistics with SPSS and Excel.

The findings indicate that number of OA journals and articles were less than that of full subscription and hybrid journals. The average rate of all citation indicators in hybrid journals were more than that of OA and full subscription journals. However, in the level of articles, the average number of citations received by OA articles (15.6) was more than that of non-OA articles (2.25).

Unlike journals, OA seems to be an advantage for articles in LIS. LIS hybrid journals receive more citations than OA and subscription journals. Thus, the authors’ approach to publishing in OA, hybrid or subscription journals and the publishers approach to the publication type may also be influenced by the findings of the present study.

The purpose of this paper is to study the influences of recess configurations on the performances of high-speed hybrid journal bearing. Hybrid journal bearing earns increasing attention in high-speed machine tool spindle owing to its intrinsic outstanding performances of low temperature rise and high stability.

To investigate the coupled effects of temperature, turbulence and the interaction between lubricant and journal/bearing bush, a thermal fluid-structure interaction approach is presented and validated by the experimental results.

Ladder-type recess has excellent tribological characteristics in decreasing temperature rise, improving stability and inhibiting cavitation, which are all beneficial to improve the performances of high-speed spindle system.

This work can be a valuable guide for the future high-speed hybrid journal bearing design.

Hybrid bearings have found increasing applications in various machines owing to their large number of favorable characteristics like high load carrying capacity, increased minimum fluid film thickness, long life and increased damping making them attractive for various applications such as turbo machinery, machine tool spindles, precision grinder spindles, etc. A careful design of such bearing for optimum performance has always been among the key issues of the researchers. The present work has been carried out to study the effect of bearing geometric parameters on performance of hybrid journal bearing and supply cut‐off behavior has also been studied for the improved performance.

The generalized Reynold's equation governing the fluid flow in the clearance space between bearing and journal has been solved using finite element method to determine the pressure distribution, subsequently performance of hole‐entry hybrid journal bearing are computed. The journal centre equilibrium position for the given load is computed and the formulation is explained. The geometric parameters include aspect ratio, land width ratio, number of rows and number of holes per row. Further, performance of the bearing is computed with increasing the load, which induces negative pressure or the backpressure at the supply holes subsequently those are plugged to support the higher load.

The obtained results are presented in graphical form and logical conclusions are drawn and the modified configurations with reduced number of holes are suggested for higher load. It is observed that the bearing configuration with aspect ratio = 1.0 and land width ratio = 0.2 is best for high load support for low power requirement as less lubricant is required to be pumped in the bearing yet it provides sufficient fluid film thickness and lower values of maximum pressure. The load carrying capacity of the bearing can be further increased by plugging the holes on which backpressure is obtained for same bearing configuration. A feedback control with hybrid bearing system will sustain the sudden increase of load by shutting off the supply of the lubricant through supply hole where negative pressure is encountered.

The paper addresses the performance of non recessed hybrid journal bearings with wide range of geometric parameter. The results are quite useful for the bearing designer. The supply cut‐off is another aspect of originality of the paper as it provides the better load support.

Noncircular journal bearings are used in industry because of their simplicity, efficiency and low cost. During the life time of a machine, these are required to be operated over a number of years and are submitted to several stops and starts. As a result, the bush becomes progressively worn out and the bearing performance changes. The purpose of this paper is to study theoretically the influence of wear on the performance of a non‐circular 2‐lobe four‐pocket multirecess hybrid journal bearing system.

The Reynolds equation governing the flow of lubricant in the clearance space of a non‐circular 2‐lobe multirecess worn hybrid journal bearing system has been solved using FEM along with appropriate boundary conditions. The defects caused by wear are centered on the load line and range from 10 per cent to 50 per cent of the bearing radial clearance.

The numerically simulated results based on a Newtonian lubricant and the steady state flow field system have been presented in terms of maximum fluid film pressure, minimum fluid film thickness, lubricant flow rate, direct fluid film stiffness and damping coefficients and stability threshold speed margin. The paper demonstrates that, for the bearing configurations studied, the bearing behavior is clearly affected by wear. The numerically simulated results indicate that for an offset factor of δ=1.2, the value of h¯_min reduces by 21.21 per cent at δ¯_w=0.5.

The presented results have valuable data in case of 2‐lobe four pocket hybrid journal bearing compensated with constant flow valve restrictor. The paper outcomes are sure to be of interest for researchers and useful for bearing designers.

The water-lubricated hydrodynamic herringbone groove journal bearing (HGJB) is capable of running at high speed. However, when running at a low speed, it suffers from a low load-carrying capacity due to the weak hydrodynamic effect. To overcome this problem, this study proposes a hybrid water-lubricated HGJB and aims to investigate its dynamic characteristics.

A hybrid lubrication model applicable to the hybrid water-lubricated HGJB is established based on the boundary fitted coordinate system, which considers the turbulent, thermal and tilting effects, and the finite difference method is used to calculate the dynamic characteristics of the hybrid water-lubricated HGJB.

The result shows that the hybrid HGJB has larger dynamic coefficients and better system stability compared with the hydrodynamic HGJB when running at low speed. Furthermore, the stiffness of hybrid HGJB are mainly governed by the hydrodynamic effect rather than the hydrostatic effect when running at high speed.

The proposed hybrid water-lubricated HGJB shows excellent dynamic characteristics at either low speed or high speed; and the hybrid water-lubricated HGJB has a large load-carrying capacity when running at low speed and has a good dynamic stability when running at high speed.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-06-2024-0233/

The slot-entry hybrid journal bearings have been successfully used in various engineering applications because of their good performance over wide range of speed and load, besides their relative simplicity in manufacturing. Most of the research work pertaining to non-recessed journal bearing assumes standard symmetric and asymmetric configurations. However, many more configurations are possible by changing the position of slot which may improve the performance of the slot-entry journal bearing. In the present work study of static performance characteristics of slot-entry journal bearing of different configuration has been carried out. The paper aims to discuss these issues.

FEM has been used to solve the Reynolds equation governing the flow of lubricant in the bearing clearance space along with the restrictor flow equation. The non-Newtonian lubricant has been assumed to follow the cubic shear stress law. The performance characteristics of slot-entry hybrid journal bearings are computed by developing a computer program.

The simulated results of bearing characteristics parameters in terms of minimum fluid-film thickness and bearing flow have been presented for the wide range of various values of non-linearity factor and external load. It is found that there is an increase in the oil requirement for slot-entry hybrid journal bearing with the specified operating and geometric parameters, when the viscosity of the lubricant decreases due to the non-Newtonian behavior of the lubricant. The effect of the decrease in the viscosity of the lubricant due to non-Newtonian behavior of the lubricant diminishes the attitude angle. The computed performance characteristics are helpful for the bearing designer while choosing a particular configuration of bearing.

The performance characteristics have been computed by considering the non-Newtonian lubricants. The thermal effects have been ignored in the analysis so as to obviate the mathematical complexity.

Get idea from already published manuscripts.

This paper aims to describe how successfully a particular restrictor delivers its best in increasing the conical journal bearing performance. The restrictors are used in the hole-entry conical journal bearing subjected to hybrid mode. Thus, the restrictors, like constant flow valve (CFV), orifice and capillary, are studied comparatively.

Numerical simulation for the bearing results with the three restrictors are obtained by using finite element method (FEM) under the well-known modified Reynolds equation.

When the hole-entry conical journal bearings, with the restrictor design parameter range C¯_s2 = 0.03 – 0.09, are operated, the results obtained are quite distinctive and significant. It indicates that the CFV restrictor-based conical bearing gives enhanced performance in comparison to orifice and capillary restrictors. Moreover, it suggests the performance-wise sequence of the restrictors in hybrid bearings as CFV > Orifice > Capillary.

The outcome of the research paper will give insight to help the bearing designer to choose the particular restrictor in hybrid conical bearing depending on the industrial need.

This study aims to deal with the performance of symmetric/asymmetric slot entry hybrid journal bearing system considering the effect of three dimensional irregularities in the analysis.

The asperity profile of three-dimensional irregularities has been modeled in both circumferential and axial directions. To compute the bearing performance characteristics parameter, finite element formulation of governing Reynolds equation has been derived using Galerkin’s technique.

Based on the numerically simulated results, it has been observed that the three-dimensional irregularities enhance the value of minimum fluid film thickness (h̄_min), lubricant flow (Q̄) and fluid film damping coefficients (C̄₁₁,C̄₂₂) approximately by order of magnitude of 24-26, 43-51 and 18-66 per cent, respectively, for the case of asymmetric slot entry configuration. Whereas, the values of fluid film stiffness coefficients (S̄₁₁,S̄₂₂) and threshold speed (ω̄_th) reduces approximately by order of 1-6 and 0-3 per cent, respectively, for the case of symmetric slot entry configuration.

The present paper describes that the influence of three-dimensional irregularities on bearing surface on the performance of slot entry hybrid journal bearing is original in literature gaps. The numerically simulated results presented in this study are expected to be quite useful to the bearing designers.

We, in the International Society for Hybrid Microelectronics, are reflecting the changes in our industry but we must also brace ourselves to accept the challenges. In our efforts within the Society to become more professional we have in fact initiated many changes and already faced many challenges. The Corporate Membership policy has been one whereby companies involved in all aspects of the hybrid microelectronic industry, suppliers, manufacturers and, of even greater importance, customers can become Corporate Members of ISHM and nominate two individual members to represent their interests. It was hoped that this would encourage more corporate backing for our projects which, if our annual exhibition, Hybrid MicroTech, is any guide, has been very successful. Our Corporate Members have beaten a path to our door in order to exhibit at this new Hybrid Microelectronics event, surely now becoming the premier meeting place for our industry in the UK.

Ranking relevant journals is very critical for researchers to choose their publication outlets, which can affect their research performance. In the management information systems (MIS) subject, many related studies conducted surveys as the subjective method for identifying MIS journal rankings. However, very few consider other objective methods, such as journals’ impact factors and h-indexes. The paper aims to discuss these issues.

In this paper, top 50 ranked journals identified by researchers’ perceptions are examined in terms of the correlation to the rankings by their impact factors and h-indexes. Moreover, a hybrid method to combine these different rankings based on Borda count is used to produce new MIS journal rankings.

The results show that there are low correlations between the subjective and objective based MIS journal rankings. In addition, the new MIS journal rankings by the Borda count approach can also be considered for future researches.

The contribution of this paper is to apply the Borda count approach to combine different MIS journal rankings produced by subjective and objective methods. The new MIS journal rankings and previous studies can be complementary to allow researchers to determine the top-ranked journals for their publication outlets.

Investigates rotation effects on hybrid plain journal bearings with various feeding mechanisms, i.e. orifice, capillary and porous feedings. Employs the numerical method of the finite difference to solve Reynolds equations. Shows that higher speed of rotation induces greater hydrodynamic load capacity, especially with an eccentricity ratio ε > 0.85. The porous and orifice feedings also result in higher load capacity than orifice and capillary feedings when the rotation speeds increase. Also analyses the multi‐array of hole‐entry of orifice and capillary feedings and the results show that the bearings with more arrays of feedings produce higher load capacity at low speed. However, the bearings with fewer arrays of feedings produce higher load capacity at high speeds. In other words, the transition from the hydrostatic to hydrodynamic load capacity of the bearing is significant to hybrid plain journal bearings.

The present work aims to predict accurately the bearing design data for non‐recessed hybrid journal bearings, considering the effect of non‐Newtonian behavior of lubricant for different symmetric and non‐symmetric bearing geometric configurations.

The simultaneous solution of generalized Reynold's equation governing the laminar flow of incompressible lubricant and the equation of flow of lubricant through the capillary restrictor, considering variable viscosity of lubricant following the “Power law”, has been carried out using FEM. For a given set of bearing geometric, operating parameters and for given external vertical load, the values of various performance characteristics have been obtained for a range of values of power law index, after establishing the journal center equilibrium position, the analysis for which has been elaborately explained.

The results obtained have been presented graphically for various bearing performance characteristics. It has been observed that with decrease in power law index “n”(0<n≤1), the value of h¯_min and load carrying capacity decreases, while bearing flow rate increases for all configuration. The load‐carrying capacity of asymmetric configurations is better and stable over entire range of restrictor design parameter. Bearing configuration with land width ratio = 0.25 and aspect ratio = 1.0, having two rows of holes and six holes in each row, will be better suited for high‐load support, as it has maximum value of minimum fluid film thickness, moderate value of bearing flow and value of attitude angle is almost constant.

The performance characteristics of journal bearing have been presented for a wide range of values of power law index and for different values of restrictor design parameter for capillary restrictor, after establishing the journal center equilibrium position. The comparison of the different symmetric and non‐symmetric journal‐bearing configurations to find the best geometric configuration at different operating conditions, considering the effect of non‐Newtonian behavior of lubricant, represents the originality of the work.

This paper aims to examine and compare extant literature on the application of multi-criteria decision-making (MCDM) techniques in humanitarian operations (HOs) and humanitarian supply chains (HSCs). It identifies the status of existing research in the field and suggests a roadmap for academicians to undertake further research in HOs and HSCs using MCDM techniques.

The paper systematically reviews the research on MCDM applications in HO and HSC domains from 2011 to 2022, as the field gained traction post-2004 Indian Ocean Tsunami phenomena. In the first step, an exhaustive search for journal articles is conducted using 48 keyword searches. To ensure quality, only those articles published in journals featuring in the first quartile of the Scimago Journal Ranking were selected. A total of 103 peer-reviewed articles were selected for the review and then segregated into different categories for analysis.

The paper highlights insufficient high-quality research in HOs that utilizes MCDM methods. It proposes a roadmap for scholars to enhance the research outcomes by advocating adopting mixed methods. The analysis of various studies revealed a notable absence of contextual reference. A contextual mind map specific to HOs has been developed to assist future research endeavors. This resource can guide researchers in determining the appropriate contextual framework for their studies.

This paper will help practitioners understand the research carried out in the field. The aspiring researchers will identify the gap in the extant research and work on future research directions.

To the best of the authors’ knowledge, this is the first literature review on applying MCDM in HOs and HSCs. It summarises the current status and proposes future research directions.

This study introduces a new approach, called the social structure approach, for ranking academic journals by focusing on hospitality and tourism journals; and a hybrid metric, including the combination of the journal impact factor via citations and a social network metric, called the journal knowledge domain index (JKDI).

Twenty-five hospitality and tourism journals were selected to test this approach. Collaboration-based metrics, productivity-based metrics, and network-based metrics are considered components of the social structure approach. Additionally, a hybrid metric, including the combination of the journal impact factor via citations and a social network metric, JKDI, is developed.

The study’s findings show that top or leading journals have a weaker position in some social structure approach metrics compared to other (or follower) journals. However, according to the JKDI, leading journals have remained constant with the other ranking studies.

The ranking of academic journals is vital for the stakeholders of academia. Consequently, the findings of this study may help stakeholders to design an optimal ranking system and formulate and implement effective research strategies for knowledge creation and dissemination.

As one of the first in the journal-ranking literature, this study has significant implications, as it introduces a new ranking approach.

The purpose of this paper is to provide an overview of one of the most important and controversial areas of scholarly communication: Open Access publishing and dissemination of research outputs. It identifies and discusses recent trends and future challenges for various stakeholders in delivering Open Access (OA) to the scholarly literature.

The study is based on a number of interrelated strands of evidence which make up the current discourse on OA, comprising the peer-reviewed literature, grey literature and other forms of communication (including blogs and e-mail discussion lists). It uses a large-scale textual analysis of the peer-reviewed literature since 2010 (carried out using the VOSviewer tool) as a basis for discussion of issues raised in the OA discourse.

A number of key themes are identified, including the relationship between “Green” OA (deposit in repositories) and “Gold” OA (OA journal publication), the developing evidence base associated with OA, researcher attitudes and behaviours, policy directions, management of repositories, development of journals, institutional responses and issues around impact and scholarly communication futures. It suggests that current challenges now focus on how OA can be made to work in practice, having moved on from the discussion of whether it should happen at all.

The paper provides a structured evidence-based review of major issues in the OA field, and suggests key areas for future research and policy development.

Where combined radial and axial loads act on the bearing, the conical journal bearing is best suited. Large turbines, generators, compressors and other machinery perform better while using conical hydrodynamic journal bearings (CHJBs). The bearings worn out and the performance suffered because of regular use and numerous start and stop operations.

The performance of CHJB is evaluated using both analytical and experimental methods in this paper. The analytical method for resolving Reynolds equation uses spherical coordinate system and finite element analysis. On the CHJB test rig, data is collected for different radial loads with 10°, 20° and 30° semi-cone angles using hydraulic oil of viscosity grade ISO VG46.

The findings of this paper demonstrate that at various semi-cone angles for worn-out bearings, the maximum pressure developed increases with increasing radial load.

This paper provides analytical and experimental performance of CHJBs considering the effect of abrasive wear that is caused because of frequent start and stop operations of machine. The results of wear impact on CHJBs will be helpful for researchers and design engineers.

The purpose of this paper is to investigate the evolution of Gold open access (OA) rates in different countries and disciplines, as well as explore the influencing factors.

In this study, employing the OA filter option of Web of Science (WoS), the authors perform a large-scale evaluation of the OA state of countries and disciplines from 1990 to 2016. Particularly, the authors consider not only the absolute number of Gold OA literature but also the ratio of them among all literature.

Currently, one-quarter of the WoS articles is Gold OA articles. Brazil is the most active country in OA publishing, while Russia, India and China have the lowest OA ratios. The OA percentage of Brazil has been decreasing dramatically in recent years, while the OA percentages of China, UK and the Netherlands have been increasing. There also exist huge differences of OA percentages across different subject categories. The percentages of OA articles in biology, life, and health-related areas are high, while those in physics and chemistry-related subject categories are very low.

With the availability of large-scale data from WoS, this study conducts a comprehensive evaluation of the Gold OA state of major countries for the first time. The variation of OA percentages is considered in light of the research profiles. OA policies in different countries and funding organizations also have an influence on the OA development.

The purpose of this paper is to consider the economic perspective in open access publishing. The status of the article processing charges in open access journals is explored and highlighted.

The study is based on the analysis of journals indexed by Directory of Open Access Journals (DOAJ) and the fee structure levied by them as article processing charges (APCs).

Open access journal publishers have to evolve a mechanism that will share the burden of the authors interested in publishing in OA journals that levy article processing charges.

The study can act as an eye‐opener for the publishers and associations affiliated with authors to support them and their works in making them publishable in open access journals which charge fees for article publishing. Also, the study can be extended on the basis of economic models that open access journals share in different disciplines and additional work can be carried out to highlight the perception of the authors who are benefitted from article processing charges.

An economic divide between the authors who belong to the developed nations and the authors who reside from third world nations can be bridged.

The study is first of its kind, as it highlights the economic burden that the authors share in a fee‐based open access publishing world.