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The purpose of this study is to investigate the influence of groove shape on the hydrodynamic characteristics of a journal bearing.

The computational fluid dynamics model also takes into account the cavitation phenomena and thermal effect, which can illustrate the lubrication performance of a journal bearing.

The hydrodynamic simulations of the journal bearing with the different groove shapes are conducted under different operation conditions.

Based on the numerical analysis, the suggestions are presented for groove shape selection and can be used to the design of a journal bearing under the extreme operation condition.

Introduction: The word “zombie” is associated with the “living dead” in our minds from horror movies we watch on TV. Recently, this concept has been used frequently to identify the firms that are still standing while they should have been closed long ago. Zombie firms are apparently active, but their cash flows are only used to compensate interest expense of their debts. Banks prefer to re-finance these firms and restructure their sunken loans rather than following their debts and moving them out of the bank’s balance sheets. However, these inefficient and unproductive firms also consume the capital that can be transferred to more productive firms. Therefore, these firms live as long as the cash inflow, which is considered as fresh blood and meat for the living dead-zombie, and they consume the resources of other living healthy firms.

Purpose: The aim of this study is to investigate the existence of zombie firms which are listed in Borsa İstanbul manufacturing industry.

Methodology: The research period is between the years 2008 and 2018, and interest coverage ratio (ICR) is used for Borsa İstanbul manufacturing firms. There are several explanations of zombie firms in the literature, which are commonly constructed on a scope of profitability of a firm. In this research, the OECD’s preferred explanation and classification of zombies is chosen which describes a zombie firm as having an ICR (operating earnings to interest expenses) which is less than 1 over three consecutive years.

Findings: It has been noted from this research that ICRs differ in the research period of Borsa İstanbul manufacturing industry firms. About 62 of 109 firms traded on Borsa İstanbul manufacturing industry between 2008 and 2018 were classified as zombie firms because they had ICRs below one for three consecutive years or over.

This paper reviews the literature on zombie firms to provide a holistic view by delineating their formation, impact, widespread nature, prevention and policy implications.

This paper uses a systematic literature review methodology, in which 76 papers published in journals ranked on the Australian Business Deans Council (ABDC) 2022 list were reviewed. The study period was from 2000 to 2022.

Among the main findings, the widespread problems of zombie firms were evident. The authors found that consistent support, either in the form of government grants or a weak financial framework, was responsible for their formation. The suboptimal performance of factors of production, depressed job creation, low innovation and overall negative impact on economic activity are the consequences of zombification. This can be controlled by ensuring better bankruptcy codes, focused on government assistance, technology use and better due diligence by banks.

This review serves as a reference point for future researchers as a cohesive and holistic study presenting a full picture of the problem, so that the proposed solutions are robust and tenable.

This review is among the initial attempts to comprehensively study published work on zombie firms in terms of analyzing their region-specific nature, with an emphasis on definition, causes, impact and prevention.

It is now well-established that good water quality is associated with economic prosperity, reduced incidence on public health and the good functioning of the various ecosystems found in our environment. Water contamination is mostly related to both diffused (agricultural lands and geologic rock degradations) and point sources of pollution. Mauritius has many water resources which depend solely on precipitation for their replenishment. Water parameters which are of relevance include total dissolved solids (TDS), temperature, pH, electrical conductivity, turbidity, dissolved oxygen, dissolved and particulate organic carbon and major cations and anions. The traditional methods of analysis for these parameters are mostly using electrical and optical methods (probes and sensors in the field), while chemical titrations, Flame AAS and High-Performance Liquid Chromatography techniques are carried out in the laboratory. Image Classification techniques using neural networks can also be used to detect the presence of contaminants in water. In addition to basic water quality parameters, the field sensors range have been extended to cover important major ions and can now be integrated with Artificial Intelligence (AI)-based models for the prediction of variations in water quality to better protect human health and the environment, reduce operation costs of water and wastewater treatment plant unit processes.

This study investigates the connection between corporate governance and zombie firm’s exit time.

With a sample of 2,794 French zombie firms, the analysis focuses on four aspects of corporate governance: board size (BS), managerial ownership (MO), director turnover (DT) and ownership concentration, using tobit regression.

Dimensions of corporate governance have an important role in determining zombie firms’ exit time. MO and ownership concentration increase zombie firm exit time, whereas larger BSs and DT reduce it.

To the best of the authors’ knowledge, this study is the first to include corporate governance as a characteristic relevant to zombie firms’ exit time. It provides new insights on why some zombie firms remain in the market longer than expected.

The Monascus pigment has been widely applied in the food processing industry as a functional additive. Lovastatin and polysaccharides are two important bio-active materials found in Monascus. Citrinin is considered as mycotoxin. Thus, it is important to produce high yields of intracellular Monascus pigments with high yields of lovastatin and polysaccharides, while maintaining low citrinin yields under liquid fermentation.

The intracellular yields of pigments, lovastatin, polysaccharides and citrinin; biomass; and reducing the sugar content of Monascus purpureus HBSD 08 were determined every day during a 10-day culturing period using lactose, maltose, sucrose, glucose, glycerine and xylose as the sole carbon sources. Additionally, the pigment composition was analysed by a thin layer chromatography (TLC) and the in vitro antitumor activities of the pigments were determined.

The maximal yield of pigments (55.44 U/mL after six days of culture) and lovastatin content (1,475.30 µg/L after five days of culture) were obtained in the presence of glucose and maltose as the sole carbon sources, respectively. The suitable carbon sources for high intracellular polysaccharides yields were sucrose, maltose and xylose. Glucose should not be chosen as the sole carbon source because of its high food safety risk. In vitro antitumor activities of pigments in the presence of different carbon sources were in the order of xylose > glucose = maltose > glycerine > sucrose = lactose. The pigment compositions in the presence of different carbon sources were the same from the TLC analysis. Thus, maltose displayed high intracellular yields of pigments, lovastatin and polysaccharides; high food safety against citrinin, and high in vitro antitumor activity during the ten days culturing period.

This study shows us the benefits of using maltose as a substrate in the production of intracellular Monascus pigments while ensuring economic and food safety.

Online review bias research has predominantly focused on self-selection biases on the user’s side. By collecting online reviews from multiple platforms and examining their biases in the unique digital environment of “Chinanet,” this paper aims to shed new light on the multiple sources of biases embedded in online reviews and potential interactions among users, technical platforms and the broader social–cultural norms.

In the first study, online restaurant reviews were collected from Dianping.com, one of China's largest review platforms. Their distribution and underlying biases were examined via comparisons with offline reviews collected from on-site surveys. In the second study, user and platform ratings were collected from three additional major online review platforms – Koubei, Meituan and Ele.me – and compared for possible indications of biases in platform's review aggregation.

The results revealed a distinct exponential-curved distribution of Chinese users’ online reviews, suggesting a deviation from previous findings based on Western user data. The lack of online “moaning” on Chinese review platforms points to the social–cultural complexity of Chinese consumer behavior and online environment that goes beyond self-selection at the individual user level. The results also documented a prevalent usage of customized aggregation methods by review service providers in China, implicating an additional layer of biases introduced by technical platforms.

Using an online–offline design and multi-platform data sets, this paper elucidates online review biases among Chinese users, the world's largest and understudied (in terms of review biases) online user group. The results provide insights into the unique social–cultural cyber norm in China's digital environment and bring to light the multilayered nature of online review biases at the intersection of users, platforms and culture.

Monascus pigment was widely applied in food processing industry as functional additive, so more attention was paid to the fermentation optimization of pigment production. Therefore, this paper aims to evaluate the best possible fermentative conditions for maximum production of biopigment using submerged fermentation (SFM) and solid state fermentation (SSF) by Monascus purpureus HBSD 08.

The biopigment was produced by using an SMF and an SSF with optimized substrate to achieve higher yield. The antioxidant activity was evaluated by DPPH radical scavenging ability, superoxide anion radical scavenging ability and hydroxyl radical scavenging ability. The pigment composition was analyzed by thin layer chromatography.

Maximum Monascus pigment production (79.6 U/ml and 1,102 U/g) were obtained under an SFM and an SFF. The antioxidant activity of the pigment in an SFM was significantly higher than that in an SFM. The composition of pigment was not different in an SFM and an SFF.

The study developed new conditions, and Monascus strain was a candidate for producing pigment in an SFM and an SFF. To the authors’ best knowledge, this is a first attempt toward comparative evaluation on antioxidant capacity and composition between pigment in an SSF and an SFM. This result will serve for Monascus pigment production.

This research conducts bibliometric analyses and network mapping on smart libraries worldwide. It examines publication profiles, identifies the most cited publications and preferred sources and considers the cooperation of the authors, organizations and countries worldwide. The research also highlights keyword trends and clusters and finds new developments and emerging trends from the co-cited references network.

A total of 264 records with 1,200 citations were extracted from the Web of Science database from 2003 to 2021. The trends in the smart library were analyzed and visualized using BibExcel, VOSviewer, Biblioshiny and CiteSpace.

The People’s Republic of China had the most publications (119), the most citations (374), the highest H-index (12) and the highest total link strength (TLS = 25). Wuhan University had the highest H-index (6). Chiu, Dickson K. W. (H-index = 4, TLS = 22) and Lo, Patrick (H-index = 4, TLS = 21) from the University of Hong Kong had the highest H-indices and were the most cooperative authors. Library Hi Tech was the most preferred journal. “Mobile library” was the most frequently used keyword. “Mobile context” was the largest cluster on the research front.

This study helps librarians, scientists and funders understand smart library trends.

There are several studies and solid background research on smart libraries. However, to the best of the author’s knowledge, this study is the first to conduct bibliometric analyses and network mapping on smart libraries around the globe.

Prefabricated technology is gradually being applied to the construction of subway stations due to its characteristic of mechanization. However, the prefabricated subway station in China is in the initial stage of development, which is prone to construction safety issues. This study aims to evaluate the construction safety risks of prefabricated subway stations in China and formulate corresponding countermeasures to ensure construction safety.

A construction safety risk evaluation index system for the prefabricated subway station was established through literature research and the Delphi method. Furthermore, based on the structure entropy weight method, matter-element theory and evidence theory, a hybrid evaluation model is developed to evaluate the construction safety risks of prefabricated subway stations. The basic probability assignment (BPA) function is obtained using the matter-element theory, the index weight is calculated using the structure entropy weight method to modify the BPA function and the risk evaluation level is determined using the evidence theory. Finally, the reliability and applicability of the evaluation model are verified with a case study of a prefabricated subway station project in China.

The results indicate that the level of construction safety risks in the prefabricated subway station project is relatively low. Man risk, machine risk and method risk are the key factors affecting the overall risk of the project. The evaluation results of the first-level indexes are discussed, and targeted countermeasures are proposed. Therefore, management personnel can deeply understand the construction safety risks of prefabricated subway stations.

This research fills the research gap in the field of construction safety risk assessment of prefabricated subway stations. The methods for construction safety risk assessment are summarized to establish a reliable hybrid evaluation model, laying the foundation for future research. Moreover, the construction safety risk evaluation index system for prefabricated subway stations is proposed, which can be adopted to guide construction safety management.