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Having read previous literature about vortex pump, we noticed that mechanisms of circulating flow and its relationship with energy transition remain unclear yet. However, this mechanism, which should be clarified, significantly influences the pump’s efficiency. To comply with the aim of investigating it, the 150WX-200-20 type pump is selected as study object in our present work.

Numerical simulation is conducted to formulate interactions between flow rate and geometric parameters of circulating flow with certain types of blade while experiments on inner flow are served as a witness to provide experimental confirmation of numerical results. Based on these, we coupled some parameters with the pump’s external performance to study their internal connections.

It is concluded that separatrix between circulating flow and other turbulent forms is not that clear under low flow rate. With flow increases, hydraulic losses coming of it will be dominant within the front chamber. Besides, we analogized circulating flow to vortices so as to make a quantitative analysis on its progressive evolution with changing flow, and vortices speaking for circulating flow can be divided into two groups. One is called main circulating flow vortex (hereinafter referred to as MCFV), which occurs all the time while subsidiary circulating flow vortices (hereinafter referred to as SCFV) appear in certain conditions. This context discusses the primary phase of our work with intent to follow up further with circulating flow characterized by vortices (hereinafter referred to as CFV). We confirmed that MCFV Vortex 1 (Vor1) directly influences the efficiency while SCFVs only play helping. As the flow goes to the given working condition, fluids in this pump tend to be steady with the size of CFVs getting larger and their shape being regular. Meanwhile, for MCFV Vor2 and Vor4, their geometric parameters are the key factors for efficiency. When CFVs become steady, they absorb other vortices nearby, as they have higher viscosity with the efficiency reaching its maximum.

The research results explore a new way to measure the circulating flow and help work out the causation of this flow pattern, which may be used to improve the vortex pump’s efficiency.

This study aims to specify whether heterogeneous reference-point-based aspirations are related to the cooperation levels of R&D alliance portfolios in a positive or negative (or nonlinear) way, and to unveil how cooperative behaviors evolve in recurrent project cooperation.

This study establishes a network containing a cooperation subnetwork and a project subnetwork based on patent data in the “deep learning” field to investigate how cooperative behaviors evolve in R&D alliance portfolios. A model of evolutionary games on complex networks is constructed to gain insight into the dynamic evolution of DMs’ strategies.

First, the heterogeneous aspirations of DMs can improve the cooperation level in R&D alliance portfolios. Second, compared to prudent DMs, aggressive DMs are more likely to choose the cooperation strategy, implying that an appropriate aspiration level nurtures cooperative R&D endeavors with partners. Third, the effects of effort complementarity, knowledge reorganization capabilities and cooperation supervision on cooperation are contingent on the distribution of DMs’ aspiration types.

Policymakers should identify aspiration types of DMs when screening partners. They can encourage partners to focus more on historical payoffs and establish relatively higher aspiration levels to improve the cooperation level. Developing highly detailed contracts becomes crucial when cooperating with firms that possess extensive knowledge reorganization capabilities.

This work contributes a theoretical framework for investigating cooperation in R&D alliance portfolios through the lens of evolutionary games on complex networks, thus revealing the effects of heterogeneous reference-point-based aspirations of DMs on R&D cooperation.

The purpose of this paper is to propose a systematic and customisable framework, titled the 9D approach, aiming to evaluate the enterprise resource planning (ERP) systems as well as to identify potential socio-technical problems, misfits and deficiencies that can cause ERP failure during the system post-implementation phase.

The proposed 9D ERP evaluation framework includes nine dimensions and 85 evaluation criteria. This theoretical framework is then used in a six-step evaluation process based on a mixed-methods design. A case study involving a large-size private company in China was used as an exemplification to illustrate how the proposed 9D approach can be applied in practices.

The findings of the study clearly demonstrated that after the ERP “go-live” point, companies still experience many challenges and problems in the post-implementation phase. These problems can be located in very diverse organisational, systemic and personnel aspects of the company, as well as across different functional areas and organisational levels. The proposed 9D approach was demonstrated to be an efficient and systematic tool to investigate and explore such ERP problems in an in-depth level within the organisational context.

This study contributes to the theory of IS evaluation in general, and provides valuable insights into the ERP post-implementation evaluation in particular.

The proposed ERP evaluation approach forms a sound base for continuous ERP improvement and contributes to sustain seamless alignment between ERP and its organisational context. The customisable feature of the framework offers flexibility and enables its use by companies of all sizes, any sector, and any country.

To the best of the researchers’ knowledge, this is the most extensive and comprehensive framework for the post-evaluation of ERPs proposed hitherto. The need for this new framework was grounded on the argumentation of the drawbacks of existing ERP measurement and evaluation studies that simply focus on success rather than the more critical failure factors.

Big data is a key component to realise the vision of smart factories, but the implementation and usage of big data analytical tools in the smart factory context can be fraught with challenges and difficulties. The purpose of this paper is to identify potential barriers that hinder organisations from applying big data solutions in their smart factory initiatives, as well as to explore causal relationships between these barriers.

The study followed an inductive and exploratory nature. Ten in-depth semi-structured interviews were conducted with a group of highly experienced SAP consultants and project managers. The qualitative data collected were then systematically analysed by using a thematic analysis approach.

A comprehensive set of barriers affecting the implementation of big data solutions in smart factories had been identified and divided into individual, organisational and technological categories. An empirical framework was also developed to highlight the emerged inter-relationships between these barriers.

This study built on and extended existing knowledge and theories on smart factory, big data and information systems research. Its findings can also raise awareness of business managers regarding the complexity and difficulties for embedding big data tools in smart factories, and so assist them in strategic planning and decision making.

The grain size and grain distribution mode have a significant impact on the tribological properties of Babbitt alloy. The purpose of this paper is to study the effect of differentiated SnSb grain size distribution on the improvement of tribological properties of Babbitt alloy.

Babbitt (marked by babbitt-cr), with a differentiated SnSb grain size distribution, was fabricated using a selective zone laser surface treatment. Bare Babbitt with coarse SnSb grain was marked as babbitt-c, and Babbitt with refined SnSb grain was marked as babbitt-r. The microstructure, microhardness and wettability of specimens were tested. The tribological properties of babbitt-c, babbitt-r and babbitt-cr were evaluated under dry and lubricated conditions.

The microstructure transforms from single coarse SnSb grain distribution or single refined SnSb grain distribution to differentiated SnSb grain size distribution, as a result of selective zone laser surface treatment. Among three specimens of microhardness, babbitt-cr showed the highest microhardness. The lipophilicity property of babbitt-cr was better compared to babbitt-c. A mixture of coarse and refined grain is beneficial to improve the tribological properties of Babbitt alloy under dry condition. Furthermore, compared with babbitt-c, the wear resistance of babbitt-cr was enhanced under lubricated condition. However, the anti-wear property of babbitt-cr was not significantly improved relative to babbitt-r with an increase in the loads.

The study demonstrates that modulated different grain size alternating distribution modes can improve the tribological properties of Babbitt alloy.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-09-2022-0259/

We examine whether the social capital of the area where a firm’s headquarters is located affects that firm’s credit rating. Given that credit rating agencies only infrequently visit a firm’s headquarters, it is pertinent to investigate whether this soft information is considered.

In order to test whether social capital affects firms’ credit ratings, we estimate the following model using an ordinary least squares regression: Rating_it = β₀ + β₁ Social Capital_it + ∑ Controls_it + Industry fixed Effects_i + State−year fixed effects_it + ε_it. We follow recent accounting and finance research and measure societal-level social capital at the county level (Jha & Chen, 2015; Cheng et al., 2017; Hasan et al., 2017a, b; Jha, 2017; Hossain et al., 2023). We use four inputs to calculate social capital: (1) voter turnout in presidential elections, (2) the census response rate, (3) the number of social and civic associations and (4) the number of nongovernmental organizations in each county.

W provide evidence that social capital has a causal effect on credit ratings. Interesting is that this effect is not merely localized to firms near credit rating agencies. We also find that the effect of social capital on credit ratings is concentrated among firms with moderate levels of default risk. For firms with extremely low or extremely high default risk, social capital appears irrelevant to credit ratings, suggesting that social capital plays a larger role in more ambiguous contexts or when greater judgment is required. We demonstrate that the effect of social capital on credit ratings disappears when the rating agency has extensive experience in a particular region. This result is consistent with rating agencies stereotyping certain regions of the USA and using that information to inform their ratings when they have less experience in the region. Finally, we find that while social capital is associated with credit ratings, it has no association with future defaults.

Though we cautiously followed prior studies and were confident in our data construction process, it is possible that we are measuring social capital with error.

Our findings suggest that credit rating agencies could benefit from reevaluating how they incorporate non-financial information, such as social capital, into their assessment processes, potentially leading to more nuanced and equitable credit ratings. Additionally, firms could use these insights to bolster their engagement with local communities and stakeholders, thereby enhancing their creditworthiness and attractiveness to investors as part of a broader corporate strategy. The findings also underline the need for regulatory frameworks that foster transparency and the inclusion of social factors in credit evaluations, which could lead to more comprehensive and fair financial reporting and rating systems.

Recognizing that social capital can influence economic outcomes like credit ratings may encourage both communities and firms to invest more in building and maintaining social networks, trust and civic engagement. By demonstrating how social capital impacts credit ratings, our research highlights the potential to address inequalities faced by regions with lower social capital, guiding targeted social and economic development initiatives. Moreover, understanding that regional social capital can influence credit ratings might affect public perception and trust in the impartiality and accuracy of these ratings, which is essential for maintaining market stability and integrity.

Our research provides fresh insights into how social capital, an intangible asset, influences credit ratings – a topic not extensively explored in existing literature. This sheds light on the dynamics between social structures and financial outcomes. Methodologically, our use of the 9/11 attacks as an exogenous shock to measure changes in social capital introduces a novel approach to study similar phenomena. Additionally, our findings contrast with prior studies such as Jha and Chen (2015) and Hossain et al. (2023), by delving deeper into how proximity and familiarity impact financial assessments differently, enriching academic discourse and refining existing theories on the role of local knowledge in financial decisions.

A new backward punch shape was designed and used in the hydroforming process of double-layer Y-shaped tubes to achieve uniform wall thickness. This study focuses on the implementation and effectiveness of this novel punch shape.

A numerical simulation and experimental validation of the hydroforming process of double-layer Y-shaped tubes under various backward punch, replenishment ratios (left and right feed ratios) and internal pressure loading paths was performed using finite elements. During the hydroforming process, an analysis was made on the distribution of stress, strain and wall thickness in both the inner and outer layers of the Y-shaped conduit.

The novel backward punch parallel to the main tube has been found to improve the distribution of wall thickness in Y-shaped tubes. By controlling the feeding ratio and modifying the loading path of the internal pressure, it is possible to obtain the optimal forming part of the double-layer Y-shaped tube. The comparison between the simulation and experimental results of the double-layer Y-shaped tube formed under the optimal path indicates that the error is within 5% and the distribution of wall thickness is consistent.

A novel backward punch technique is employed to control the hydroforming process in a Y-shaped tube. A study on hydroforming of double-layer Y-shaped tubes with asymmetric features and challenging forming conditions is being suggested.

Project-based temporary organizations, as an efficient organizational form for the execution of complex and innovative tasks, encounter challenges in fostering the effectiveness of inter-organizational cooperation within their temporary, uncertain, and dynamic nature. Although change-oriented organizational citizenship behaviors are recognized for promoting organizational relationships and performance in changing contexts, research in temporary organizational settings remains sparse. This study diverges from the majority concentrating on change-oriented behaviors on intra-organizational leader-employee relations and behaviors, aiming to propose a dynamic adaptive capacity of organizational leaders and explore how leadership capabilities and organizational climate shape their change-oriented organizational citizenship behaviors at inter-organizational level.

Developing a person-organization fit model tailored for complex and dynamic organizational settings, using survey data from 225 leaders with project cooperative experience and structural equation modeling for empirical analysis.

This study reveals the direct positive influences of organizational leaders’ dynamic adaptive capacity on their changed-oriented organizational citizenship behaviors. And, change self-efficacy, as a mediating psychological trait, enhances the positive relation between dynamic adaptive capacity and changed-oriented organizational citizenship behaviors. The findings also highlight person-organization interactions, where organizational justice, acting as a situational and moderating factor, has a positive yet disruptive effect on the relationship between dynamic adaptive capacity, change self-efficacy, and changed-oriented organizational citizenship behaviors.

This research enriches the mechanisms linking dynamic managerial capability in organizational leadership to citizenship behaviors at the micro-level, providing valuable insights for the management and development of temporary cross-organizational cooperation.

The purpose of this paper is to enhance the performance of robots in peg-in-hole assembly tasks, enabling them to swiftly and robustly accomplish the task. It also focuses on the robot’s ability to generalize across assemblies with different hole sizes.

Human behavior in peg-in-hole assembly serves as inspiration, where individuals visually locate the hole firstly and then continuously adjust the peg pose based on force/torque feedback during the insertion process. This paper proposes a novel framework that integrate visual servo and adjustment based on force/torque feedback, the authors use deep neural network (DNN) and image processing techniques to determine the pose of hole, then an incremental learning approach based on a broad learning system (BLS) is used to simulate human learning ability, the number of adjustments required for insertion process is continuously reduced.

The author conducted experiments on visual servo, adjustment based on force/torque feedback, and the proposed framework. Visual servo inferred the pixel position and orientation of the target hole in only about 0.12 s, and the robot achieved peg insertion with 1–3 adjustments based on force/torque feedback. The success rate for peg-in-hole assembly using the proposed framework was 100%. These results proved the effectiveness of the proposed framework.

This paper proposes a framework for peg-in-hole assembly that combines visual servo and adjustment based on force/torque feedback. The assembly tasks are accomplished using DNN, image processing and BLS. To the best of the authors’ knowledge, no similar methods were found in other people’s work. Therefore, the authors believe that this work is original.

The geological conditions of Longyang Reservoir are complex and it is located in strong earthquake area. In order to determine its seismic characteristics, the seismic response and residual deformation of embankment dam should be studied to provide calculation basis for dam design and construction.

Based on the geological survey data of Longyang Reservoir, the dam filling materials are tested by dynamic deformation tests, and the equivalent linear constitutive model parameters of the filling materials are obtained. Based on Duncan-Chang E-B model, the stress state of embankment dam in Longyang Reservoir before earthquake is calculated, and the dynamic response and earthquake residual deformation of embankment dam in Longyang Reservoir under earthquake condition are calculated by using equivalent linear model and Shen Zhu-jiang’s residual deformation model.

The results show that with the increase of dynamic shear strain, the dynamic shear modulus decreases and the damping ratio increases. The scatter plot between dynamic shear modulus and dynamic shear strain, and the scatter plot between damping ratio and dynamic shear strain under different confining pressures show strips. The calculation results shows that the acceleration of embankment dam in Longyang Reservoir increases with the increase of dam height, and the acceleration distribution has obvious amplification effect. Combined with the maximum dynamic shear strain during the earthquake and the state before the earthquake, the maximum vertical residual deformation of embankment dam in Longyang Reservoir is 2.98 cm which occurs at the top of the dam, calculated by the Shen Zhu-jiang’s residual deformation model.

Finite element calculation model parameters of embankment dam are obtained by dynamic triaxial tests. Seismic dynamic responses and residual deformation of embankment dam are analyzed. With the increase of dam height, the acceleration distribution shows an obvious amplification effect. The vertical displacement of embankment dam is larger along the dam axis and decreases in the upstream and downstream direction. The maximum horizontal displacement of embankment dam occurs in the middle of upstream and downstream dam slopes.

• (1)

  Finite element calculation model parameters of embankment dam are obtained by dynamic triaxial tests.

• (2)

  Seismic dynamic responses and residual deformation of embankment dam are analyzed.

• (3)

  With the increase of dam height, the acceleration distribution shows an obvious amplification effect.

• (4)

  The vertical displacement of embankment dam is larger along the dam axis and decreases in the upstream and downstream direction.

• (5)

  The maximum horizontal displacement of embankment dam occurs in the middle of upstream and downstream dam slopes.

Finite element calculation model parameters of embankment dam are obtained by dynamic triaxial tests.

Seismic dynamic responses and residual deformation of embankment dam are analyzed.

With the increase of dam height, the acceleration distribution shows an obvious amplification effect.

The vertical displacement of embankment dam is larger along the dam axis and decreases in the upstream and downstream direction.

The maximum horizontal displacement of embankment dam occurs in the middle of upstream and downstream dam slopes.