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Sustainable supply chain finance (SSCF) is a fascinated consideration for both academics and practitioners because the indicators are still underdeveloped in achieving SSCF. This study proposes a bibliometric data-driven analysis from the literature to illustrate a clear overall concept of SSCF that reveals hidden indicators for further improvement.

A hybrid quantitative and qualitative approach combining data-driven analysis, fuzzy Delphi method (FDM), entropy weight method (EWM) and fuzzy decision-making trial and evaluation laboratory (FDEMATEL) is employed to address the uncertainty in the context.

The results show that blockchain, cash flow shortage, reverse factoring, risk assessment and triple bottom line (TBL) play significant roles in SSCF. A comparison of the challenges and gaps among different geographic regions is provided in both advanced local perspective and a global state-of-the-art assessment. There are 35 countries/territories being categorized into five geographic regions. Of the five regions, two, Latin America and the Caribbean and Africa, show the needs for more improvement, exclusively in collaboration strategies and financial crisis. Exogenous impacts of wars, natural disasters and disease epidemics are implied as inevitable attributes for enhancing the sustainability.

This study contributes to (1) boundary SSCF foundations by data driven, (2) identifying the critical SSCF indicators and providing the knowledge gaps and directions as references for further examination and (3) addressing the gaps and challenges in different geographic regions to provide advanced assessment from local viewpoint and to diagnose the comprehensive global state of the art of SSCF.

To improve the load capacity and stability of gas foil journal bearings (GFJB), this paper aims to propose a novel GFJB with taper-grooved top foil.

A modified bump stiffness model is established considering rounding and friction. By considering the variation of clearance in the circumferential and axial direction, the static and dynamic characteristics of the novel bearing are calculated using the finite difference method, and perturbation method, respectively. The bearing performance under different groove parameters is studied and compared to the traditional bearings.

The results show that this novel GFJB can bring multi-extra local dynamic pressure and decrease the gas end leakage, which improves the static and dynamic properties. Moreover, as the increment of groove depth, the load capacity and direct stiffness are reinforced. There is an optimal groove width to maximize the load capacity, and the taper-groove is more beneficial to the improvement of bearing performance than other groove shapes. For the novel GFJB (Ng = 6, Hg = 10µm), the load capacity and direct stiffness increase by about 6.67 and 13.5 per cent, respectively. The stability threshold speed (STS) of a rotor supported by the novel bearings is also increased.

The performance of the presented novel GFJB is enhanced immensely compared to the traditional bearings, and the results are expected to be helpful to bearing designers, researchers and academicians concerned.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-08-2019-0307.

The purpose of this paper is to study the effect law of roundness error on the properties of gas foil conical bearing (GFCB), and the performance of bearings with different non-circular sleeve shapes are calculated.

For the bump-type GFCB, the nonlinear bump foil stiffness model and 1-D beam top foil stiffness model are built. On this basis, the finite element method and finite difference method are used to solve the Reynolds equation and the film thickness equation coupled, and the static and dynamic properties of GFCB are calculated. The effect law of sleeve roundness error on the static performance under different conditions is obtained. Moreover, the dynamic stiffness and damping characteristics under different errors are also studied.

The roundness error will decrease the load capacity and friction torque of GFCB, and increase the attitude angle. The error effect is more dramatic when there is larger eccentric, small nominal clearance, larger error value and more error lobes, and the static performance exhibits a periodic change in the circumferential direction. The roundness error can also decrease the direct stiffness and cross-coupled damping of GFCB, while the cross-coupled stiffness increases largely, which will reduce the bearing stability.

The roundness error adversely affects the static and dynamic characteristics of GFCB, which should be concerned by bearing designers, researchers and academicians.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-01-2020-0019/

The purpose of this paper is to study the characteristics of gas foil conical bearings (GFCBs) considering the misalignment, the static and dynamic performances with different misalignment cases were studied.

A test rig on the air compressor supported by GFCBs has been developed to measure the practicability. A nonlinear bump stiffness model and one-dimensional beam top foil stiffness model were used as a basis for the calculation of static and dynamic performance. The finite element method and finite difference method are adopted to solve the Reynolds equation and the film thickness equation coupled, in which different misalignment cases were considered by changing the film thickness.

The supporting performance of GFCB is excellent, and the film clearance plays a critical role. The misalignment effects depend on the assembled angle and the misalignment angle. The load capacity, friction torque, temperature of GFCB decrease when the misalignment assembled angle is between 120° and 240°, while the dynamic bearing stability is improved. The static and dynamic performances show the opposite law for the other assembled angles, and the misalignment effect is more dramatic when there is a larger misalignment angle. Moreover, the bearing and running parameters largely affect the bearing performance.

The present study focuses on the static and dynamic characteristics of GFCB and investigates the effects of misalignment on the bearing performance.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-04-2020-0117

This paper aims to study the bearing performance with different cone angle errors, to study the effect law of manufacturing taper error on the properties of gas foil conical bearing (GFCB).

For the GFCB supported by separated bump foil strips, a nonlinear structure stiffness model considering Coulomb friction and arch characteristics was proposed. The finite element method and finite difference method were used to solve the Reynolds equation and the film thickness equation by coupling, and the properties of the GFCB were obtained. The effect of foil and bearing structure parameters on the static and dynamic performance under different taper error cases was analyzed. Moreover, a test on the air compressor supported by GFCBs was conducted to verify the practicability.

The taper error has a largely adverse effect on the load capacity of GFCB. When the taper error is −0.03°, the radial load capacity Fr and axial load capacity Fz decrease by 37.5 and 58.3%, respectively. The taper error decreases the direct stiffness and cross-coupled damping of GFCB, which will weaken the bearing stability. Moreover, the performance of GFCB is closely related to the foil and bearing parameters.

The taper error adversely affects the static and dynamic characteristics of GFCB, which should be concerned by bearing designers, researchers and academicians.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-03-2020-0089/

The purpose of this paper is to investigate the effect of different wedge shapes on the performance of air foil thrust bearing (AFTB).

During the study, a bump foil stiffness model considering slip deformation and a two-dimensional sheet top foil model is established, and the Reynolds equation and film thickness equation is solved using the finite difference method and finite element method. The static performance such as load carrying capacity, friction torque and power loss of AFTB under different taper parameters is obtained. The influence of different pitch ratio, film thickness ratio and wedge shapes on the bearing characteristics is studied.

There is an optimal height and a pitch ratio for the taper of AFTB with certain tile number. Compared to the plane and concave wedge shape, the upper convex shape can enhance the convergence effect of the wedge region, increase the effective film pressure distribution area of the bearing and reduce the local concentrated load of the top foil, which is more conductive to the increase of load capacity.

The wedge shape parameters bring a fundamental difference in the static performance of AFTB. The results are expected to be helpful to bearing designers, researchers and academicians concerned.

The purpose of this paper is to investigate the effect of the rounding in bump foil on the static performance of air foil journal bearings.

During the study, the bending moment of the new foil structure with rounding is proposed, and the bump foil stiffness is obtained from the elastic deformation energy theory. The validity of the presented foil model is verified through comparison with previous models. The static characteristics of foil bearings such as film thickness and attitude angle are obtained using a fully coupled elastic-gas algorithm and are compared to models with various rounding radius and friction coefficients.

There is an optimal rounding radius that makes the stiffness of bump foil maximum. As the static load increases, the minimum film thickness is proportional to the rounding radius but the attitude angle is inversely proportional. The effect of rounding with a large friction coefficient becomes negligible.

The rounding brings fundamental difference in the structural stiffness and static performance of foil bearings. The results are expected to be helpful to bearing designers, researchers and academicians concerned.

This paper aims to improve the load capacity of gas foil thrust bearing (GFTB) and to introduce and study a novel bearing with stacked bump foils.

For the proposed novel GFTB supported by stacked foils, some bump-type gaskets with several partial arches are inserted below the regular bump foil, and the height of each arch can be made differently. These features make the bump foil thickness and height gradually increase, which can bring enhanced support stiffness and convergent film at the trailing edge. Based on a new nonlinear bump stiffness model considering bump rounding and friction force, the finite element and finite difference method were used to solve the coupling Reynolds equation, energy equation and foil deformation equation. Finally, the structural stiffness and static characteristics of the novel GFTB were gained and compared with the traditional bearing.

The novel GFTB has an additional convergence effect in the parallel section, which improves the static performance of bearing. The bearing capacity, friction moment, power loss and temperature rise of the novel GFTB are all higher than those of the traditional bearing, and the static characteristics are related to the parameters of stacked bump foils.

The stacked bump foils bring a fundamental enhancement on the load capacity of GFTB. The results are expected to be helpful to bearing designers, researchers and academicians concerned.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-10-2019-0449/

This study investigates the economic outcomes of organic farming controlling for the four major aspects of a cropping system, including climate, genotypes, management and soil. Considering possible variations in treatment responses, this study also presents empirical evidence of heterogeneous treatment effects associated with spatial agglomeration or farm covariates.

Rice farm households data taken from the 2015 Agriculture Census is merged with township-level seasonal weather data, crop suitability index and average income per capita in Taiwan. To address the selection bias problem, the authors apply the Probit-2SLS instrumental variable (IV) method in the binary treatment model under homogeneous and heterogeneous assumptions.

It is found that organic farming leads to a significantly positive effect on rice farms' economic performances in terms of cost reduction and profit growth. This positive treatment effect is more sizable with spatial agglomeration. Furthermore, the treatment effect of organic farming is found to vary with the farm characteristics such as farmland area and the number of hired workers.

Two important implications for the promotion of sustainable agri-food production are inferred: (1) establishing organic agriculture specialized zones may benefit rural development; (2) providing economic incentives to small farms to expand their scale may be a more effective policy means to promote sustainable agri-food production.

The findings in this study complement the body of knowledge by drawing insights from the agriculture census data and providing profound evidence of the heterogeneous outcomes of organic farming due to spatial clustering and farm covariates.

This paper aims to study the clearance compatibility of active magnetic bearing (AMB) and gas bearing (GB) to achieve a single-structured hybrid gas-magnetic bearing (HGMB), which uses a single bearing structure to realize both the functions of gas bearing and magnetic bearing.

Because the radial clearance size of the AMB is typically ten times larger than that of the GB, radial clearance compatibility of GB and AMB needs to maximize the radial clearance of GB by adjusting structural parameters. Parametric analysis of structural parameters of GB is explored. Furthermore, a general structural design principle based on static analysis, rotordynamic performance and system stability is established for the single-structured HGMB.

Load capacity is vastly reduced due to the enlarged radial clearance of the GB. A minimum clearance needs to be ensured by increasing the bearing diameter or width to compensate for the reduced load capacity, yet indirectly raising the bearing load. Increased bearing load is conducive to stability, yet it raises the risk of rotor abrasion. In addition, excessively large bearing diameter leads to system instability, and inappropriate bearing width affects critical speeds. A general structural design principle is established and the designed HGMB–rotor processes optimal performances.

A single-structured HGMB is proposed to address the urgent demand for high-speed, cryogenic turboexpanders with frequent starts/stops. This design applies a single-bearing structure to realize the characteristics of both GB and AMB, greatly simplifying the implementation, reducing air friction loss and raising critical speeds. This paper provides a fresh perspective on the development of cryogenic turboexpanders for hydrogen liquefaction. It theoretically validates the feasibility and provides a design guide for a single-structured HGMB system.