Nan Gao, Shiyu Wang and Muhammad Asad Ur Rehman Bajwa
Gear transmissions are widely utilized in practice. This paper aims to uncouple the crack feature from the cracked time-varying mesh stiffness (TVMS) and investigate the effects…
Abstract
Purpose
Gear transmissions are widely utilized in practice. This paper aims to uncouple the crack feature from the cracked time-varying mesh stiffness (TVMS) and investigate the effects of the crack on the nonlinear dynamics of a spur gear pair.
Design/methodology/approach
An approximate method to simulate the cracked TVMS is proposed by using an amplitude modulation function. The ratio of mesh stiffness loss is introduced to estimate the TVMS with different crack depths and angles. The dynamic responses are obtained by solving a torsional model which takes the non-loaded static transmission error, the backlash and the cracked TVMS into account. By using the bifurcation diagram, the largest Lyapunov exponent (LLE) and dynamic mesh force, the influences of crack on nonlinear behaviors are examined. The dynamic characteristics are identified from the phase diagram, Poincaré map, dynamic mesh force, time series and FFT spectra.
Findings
The comparison between the healthy and cracked gear pairs indicates that the crack affects the system motions, such as the obvious changes of impact force and unpredictable instability. Besides, the additive and difference combination frequencies can be found in periodic-1 and -2 motions, but they are covered in periodic-3 and chaotic motions. Deeper crack is an important determinant of the nonlinear behaviors at a higher speed.
Originality/value
The research provides an interesting perspective on cracked TVMS and reveals the connection between crack and nonlinear behaviors of the gear pairs.
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Shujing Li and Nan Gao
The purpose of this paper is to explore the influence of the rise in housing prices on enterprise financing and also the sustainability and heterogeneity of this effect.
Abstract
Purpose
The purpose of this paper is to explore the influence of the rise in housing prices on enterprise financing and also the sustainability and heterogeneity of this effect.
Design/methodology/approach
Empirical test, panel data, fixed-effect model, IV and 2SLS were used in this paper.
Findings
The empirical results indicate that the mortgage effect does exist, and the authors further analyze the heterogeneity of this effect by dividing the sample based on the degree of financial development and property rights; the empirical results reveal that the mortgage effect is significantly higher in places with the high level of financial development. Besides, compared to the SOE enterprise, the mortgage effect has more influence on non-SOE companies.
Research limitations/implications
The results indicate that the mortgage effect should be considered when regulating housing market, and in order to improve the financing capability of company, its profitability and financial market efficiency should be emphasized.
Originality/value
This paper not only confirms the existence of the mortgage effect, but also explores its sustainability and heterogeneity, which reveals the risk and bubble in the effect of house market on enterprise financing, and enlightens how to promote financing ability of company.
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Fu-Wang Yang, Jiang-Min Huang, Guan-Jun Zhang, Chenxi Zhang, Dong-Lan Sun, Nan-Feng Gao and Shouzhi Yi
The phosphorus and zinc contained in zinc dialkyl dithiophosphate (ZDDP) caused severe environment pollution and catalyst poison. Thus, the phosphorus-free additive, such as…
Abstract
Purpose
The phosphorus and zinc contained in zinc dialkyl dithiophosphate (ZDDP) caused severe environment pollution and catalyst poison. Thus, the phosphorus-free additive, such as borate esters, has become one of studying hot topics in the area of oil additive. However, the stability of hydrolysis greatly limited the use of borate esters. The purpose of this paper is to improve the stability of hydrolysis by synthesizing a new kind of N-containing heterocyclic borate ester (MTTDB) as a lubricant additive.
Design/methodology/approach
The tribological properties of novel borate ester (MTTDB) as an additive in the base oil were studied by a four-ball machine. The element composition and chemical state of the tribofilm were investigated by scanning electron microscopy, energy dispersive spectrometer and X-ray photoelectron spectroscopy.
Findings
The results showed that the base oil lubricated by MTTDB exhibited high hydrolytic stability, good anti-wear property and excellent extreme pressure performance. When 2.5 per cent MTTDB was added into the 100N base oil, the smallest wear scar diameter (0.46 mm) was obtained. Furthermore, the decomposed borate ester, organic sulfide adsorbed on the worn surface was detected, and S element reacted with the steel surface and generated FeSO4, both of which contributed to the formation of the tribofilm.
Originality/value
Based on N-containing heterocyclic compounds, for instance, thiadiazole derivatives, introducing nitrogen and sulfur elements into borate ester, a new kind of N-containing heterocyclic borate ester (MTTDB) exhibited excellent property in hydrolysis stability, friction-reducing, anti-wear and extreme pressure. This synthesized method would be helpful for the borate ester used as additive in engine oil, gear oil and other industrial lubricants.
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Xiao Yang and Xinbo Qian
Hydraulic slide valve failure often results from competing failure modes, termed competitive failure. To enhance prediction accuracy for hydraulic slide valve remaining useful…
Abstract
Purpose
Hydraulic slide valve failure often results from competing failure modes, termed competitive failure. To enhance prediction accuracy for hydraulic slide valve remaining useful life, the authors propose a method incorporating competitive failure and Monte Carlo simulation. This method allows for more accurate prediction of hydraulic slide valve remaining useful life.
Design/methodology/approach
In this paper, the competitive failure mode of the hydraulic slide valve is analyzed by studying the two failure modes of the hydraulic slide valve, and the prediction of the remaining useful life of the hydraulic slide valve is studied by using the sample set generated by Monte Carlo simulation and the competitive failure joint model.
Findings
The results show that the proposed prediction method based on competitive failure and Monte Carlo simulation is more accurate than the traditional Bayesian joint model prediction method when dealing with the failure mode competition phenomenon of hydraulic slide valve.
Originality/value
In this paper, the remaining useful life prediction of hydraulic slide valve with competitive failure characteristics is studied, which provides a new idea for the remaining useful life prediction method.
Peer review
The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-11-2023-0361/
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Alexandra Panagiotis Pliakoura, Grigorios Beligiannis and Achilleas Kontogeorgos
Literature contributions to agricultural cooperative (AC) entrepreneurship model are fragmented and show some significant limitations. The purpose of this paper is to identify the…
Abstract
Purpose
Literature contributions to agricultural cooperative (AC) entrepreneurship model are fragmented and show some significant limitations. The purpose of this paper is to identify the existing important barriers to this entrepreneurship model as well as to group them into respective themes.
Design/methodology/approach
A systematic literature review (SLR) of peer reviewed journal articles was carried out by the authors in well-known databases, such as Scopus, Emerald, ScienceDirect, Google Scholar, IDEAS/RePEc search and Web of Science. In total, 78 articles from 26 different countries during 2010–2019 were collected.
Findings
A large number of important barriers are identified in the literature and meaningful dimensions of these barriers are also revealed.
Practical implications
The study has important implications regarding the ways to improve the effectiveness of AC model. Researchers and practitioners can use the results presented in this study for further development of this model.
Originality/value
This study presents the important barriers in AC model in global scope analytically and groups them into meaningful themes, which significantly differentiate the present SLR study from those published so far.
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Rong Kong, Yanling Peng, Nan Meng, Hong Fu, Li Zhou, Yuehua Zhang and Calum Greig Turvey
In this study, the authors examined demand-side credit in rural China with the aims of understanding attribute preferences and the willingness of farmers to pay for credit.
Abstract
Purpose
In this study, the authors examined demand-side credit in rural China with the aims of understanding attribute preferences and the willingness of farmers to pay for credit.
Design/methodology/approach
The authors implemented an in-the-field discrete choice experiment (DCE) using a D-optimal block (6 × 9 × 3) design applied to 420 farm households across five Chinese provinces (Shandong, Sichuan, Shaanxi, Jiangsu and Henan) in the summer and fall of 2018. The DCE included six attributes including the interest rate, term of loan, type of loan, type of repayment, type of institution and mobile banking services.
Findings
Conditional and mixed logit results indicated a downward sloping credit demand curve with variable elasticity across regions. Provincial willingness-to-pay (WTP) indicators suggested that farmers were willing to pay a premium for long-term ( 0.03–0.687%) and low collateral credit loans ( 0.79–2.93%). Also, four of five provinces indicated a preference for loan amortization rather than lump-sum payment. Interestingly, in comparison to the Agricultural Bank of China (ABC), only farmers in Shandong, Sichuan and Shaanxi indicated a preference for rural credit cooperatives (RCCs)/banks and the Postal Savings Bank of China (PSBC). Another quite surprising result was bank services, in our case, access to mobile banking did not appear to induce WTP for agricultural credit. While conditional and mixed logit regression coefficients were similar (and therefore robust), the authors found that there was substantial heterogeneity across attribute preferences on term of loan, type of loan and amortization. Preferences for type of lender and mobile banking were generally homogenous. This result alone suggested that lenders should consider offering a suite of credit products with different attributes in order to maximize the potential pool of borrowers. While there were some differences across provinces, farmers appeared to be indifferent to lenders, and it did not appear that offering banking services such as mobile banking had any bearing on credit decisions.
Research limitations/implications
This paper presents a first step in using in-the-field choice experiments to better understand rural finance in China. Although the sample size satisfies conventional levels of significance and rank conditions, the authors caution against attributing results to China as a whole. Different provinces have different institutional structures and agricultural growing conditions and economies and these effects may differentially affect WTP for credit. Although by all indications farmers were aware of credit, not all farmers, in fact a minority, actually borrowed from a financial institution. This is not unusual in China, but for these farmers, the DCE was posed as hypothetical. Likewise, the study’s design was based on a generic credit product typical of rural China, and the authors caution against making inferences about other products with different attributes and risk structures.
Social implications
This study is motivated by the rapidly changing dynamic in China's agricultural economy. With specific reference to new laws and regulations about the transfer of land use rights (LURs), China's agricultural economy is undergoing significant and rapid change which will require better understanding by policy makers, lenders and practitioners of the changing credit needs of farmers, including the new and emerging class of commercial farmers.
Originality/value
To the best of the authors’ knowledge, the authors believe that the result provided in this paper present the first use of in-the-field DCE and are the first to be reported in either the English or Chinese literature on rural credit product design.
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Zahra Mosallanezhad, Cain Clark, Fatemeh Bahreini, Zahra Motamed, Abdolhamid Mosallanezhad, Seyedeh Fatemeh Hosseini, Aneseh Shaban-Khalaf and Zahra Sohrabi
The purpose of this systematic review and meta-analysis was to investigate the efficacy of propolis on glycemic indices in type 2 diabetic patients.
Abstract
Purpose
The purpose of this systematic review and meta-analysis was to investigate the efficacy of propolis on glycemic indices in type 2 diabetic patients.
Design/methodology/approach
Web of science (ISI), Embase, Scopus and PubMed were systematically searched to find randomized controlled trials (RCTs) assessing the effects of propolis intake on glycemic controls in type 2 diabetic patients, from inception up to September 1, 2020. A random-effects model was used to pool weighted mean difference (WMD). Meta-regression was performed to detect the potential sources of inter-study heterogeneity.
Findings
Seven trials were included in the meta-analysis. Compared to controls, propolis intake significantly improved serum fasting blood sugar (FBS) (WMD = −13.62 mg/dl, 95% CI = [−23.04, −4.20], P = 0.005, I2 = 58.5%) and hemoglobin A1C (HbA1c) (WMD = −0.52%, 95% CI = [−0.86, −0.18], P = 0.002, I2 = 64.0%). In contrast, receiving propolis did not change serum insulin (WMD = −1.46 (uIU/ml), 95% CI = [−2.94, 0.02], P = 0.05, I2 = 75.0%) and homeostatic model assessment for insulin resistance (HOMA-IR) (WMD = −0.98 (%), 95% CI = [−2.00, 0.04], P = 0.06, I2 = 82.3%) compared to controls.
Originality/value
The present meta-analysis demonstrated that propolis intake significantly reduces serum FBS and HbA1c in diabetic patients but does not alter serum insulin and HOMA-IR. Further large-scale RCT’s are needed to approve these effects.
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Eman Almehdawe, Saqib Khan, Manish Lamsal and Angèle Poirier
The purpose of this paper is to identify the factors that affect the Canadian credit unions' financial performance which play an important role in providing financial services to…
Abstract
Purpose
The purpose of this paper is to identify the factors that affect the Canadian credit unions' financial performance which play an important role in providing financial services to the agriculture sector.
Design/methodology/approach
We surveyed the literature to identify different performance metrics of credit unions and a set of possible factors that might affect their performance. We collected data related to different dependent and independent variables from financial statements and balance sheets of 189 credit unions and from general websites like Statistics Canada and Bank of Canada. Then, we imputed the missing data and developed fixed effect and random effect panel data regression models. First, we used return on asset as the main dependent variable. Afterwards, we used six performance metrics to check the robustness of our models.
Findings
From an initial list of 16 possible factors that might affect the financial performance of a credit union, we were able to narrow the factors down to the nine most significant ones. It was observed that credit unions in the prairies were more likely to perform well financially as compared to other provinces. Membership size, the size of a credit union in terms of total assets, capital adequacy ratio, market penetration, diversification of income, inflation rate and provincial GDP and interest rates were significant. The cross-sectional analysis performed confirmed the findings of the fixed effect panel data models.
Research limitations/implications
This study has a limitation concerning the number of years included into the time series analysis. Only ten years worth of data were available.
Practical implications
Results provide credit union management, service providers for credit unions and market analysts with a current understanding of how different internal and external factors might affect return on assets, return on equity, delinquency, cash ratio, efficiency ratio, asset growth and loan growth. Our models can be used to predict financial performance of credit unions based on the defined significant variables.
Originality/value
Although there is a wide body of literature that studies performance of banks, not many studies focus on credit unions. Moreover, the existing studies are based on credit unions in United States or Europe, and literature on Canadian credit unions is scarce. The data collected covered 189 Canadian credit unions. To our knowledge this is the first study that looks at the various internal, external and regulatory factors together that affect the credit unions in various jurisdictions of Canada.
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Masaood Moahid, Ghulam Dastgir Khan, Yuichiro Yoshida, Keshav Lall Maharjan and Imran Khan Wafa
This research measures the causal effects of pertinent agricultural credit policy attributes on farmers' participation probability and their willingness to pay (WTP) for…
Abstract
Purpose
This research measures the causal effects of pertinent agricultural credit policy attributes on farmers' participation probability and their willingness to pay (WTP) for agricultural credit and its associated services.
Design/methodology/approach
A randomized conjoint field experiment is conducted in three districts of Nangarhar Province, Afghanistan, capturing stated-preference data of 300 farmers. Each survey participant was provided with two hypothetical choices and one opt-out option to generate rankings based on their preferences. The levels of six attributes—namely, the credit service provider's location, the time required to obtain credit, the frequency of installments, the type of loan security, the provider of the credit services and the annual membership fee to participate in the proposed policy—are randomly assigned to produce the alternative choices.
Findings
The results reveal that farmers support the suggested agricultural credit services policy (ACSP), and the lower bound of their WTP for participation in the policy is as high as 5% of their average annual income.
Practical implications
This study provides evidence-based policy input for designing effective agricultural credit policies in Afghanistan, which can be extended to other countries with a similar context.
Originality/value
This is the first study estimating the causal effects of formal agricultural credit policy attributes on farmers' participation probability. Further, this study nonparametrically measures farmers' WTP for participation in the proposed policy.
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Outlines Hong Kong’s financial system during the pre‐unification era. Looks at recent issues, regulatory changes and its development as an international financial centre…
Abstract
Outlines Hong Kong’s financial system during the pre‐unification era. Looks at recent issues, regulatory changes and its development as an international financial centre. Considers banking, the stock market, the bond & futures market, the gold market, regulatory bodies and monetary and currency policies. Contrasts these with the pre‐unification system in China. Outlines the way that these two systems propose to exist together, looking at the potential benefits and problems this may bring.