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The purpose of this paper is to investigate the track evolution and surface characteristics of selective laser melting Ti₆Al₄V.

In the present paper, Ti₆Al₄V single-track, multi-track and bulk sample were formed at different scanning speed by selective laser melting (SLM). Then, the surface morphology, three-dimension profile and surface roughness were evaluated. The width of the single and multi-track was measured and compared.

The results showed that the heat accumulation played a great role on the evolution of tracks and surface characteristics from single-track to multi-track and to bulk. The surface morphology of the subsequent tracks became more regular when the single-track was irregular at the same high scanning speed. The width of last track Wn was always larger than that of the first track W1. The Ra of the top of the bulk increased with the increase of the scanning speed, this trend was as same as the Ra of the single-track, but the trend of Ra of the side was opposite.

The effect of heat accumulation on the track evolution and surface characteristics is obtained. The results can help to derive a smooth surface with a regular and continuous track in SLM.

This paper aims to investigate the evolution of operations management (OM) research along two major dimensions from 1977 to 2003 and discusses possible paths for research progression in the future.

To identify OM research papers, a careful definition of OM research was constructed based initially on earlier work and then more precisely extended through empirical analysis. The research on OM builds on a previous study that took snapshots of OM research in 1977 and 1987. It then extends and updates it through a content analysis of 593 articles published in 1995 and 2003 in five journals recognized for publishing OM research.

The overall results illustrate that OM has evolved from heavily rationalistic, axiomatic analyses based on artificial reconstructions of reality toward more interpretive analyses based on natural observations of reality.

As the OM field continues to evolve, it is important to monitor and reassess published research to discern its changing dimensions. While this effort is not an exhaustive review of all OM research and does not consider all relevant journals and years, it does offer the “big picture” perspective needed for analyzing changing research approaches in the field.

The research provides an analysis of the evolution of knowledge creation within the field and possible paths for its future development. The practical implications are that as research becomes more interpretive and observation‐based, the findings will have more relevance for managers and the problems they face.

While several authors have analyzed the OM field relative to select research methods and journals, this paper provides a broader and more encompassing view of OM research along two important research dimensions: the researcher's framework and the source of the data.

This paper aims to describe and investigate the mathematical models and numerical modeling of how a cell membrane is affected by a transient ice freezing front combined with the influence of thermal fluctuations and anisotropy.

The study consists of mathematical modeling, validation with an analytical solution, and shows the influence of thermal noises on phase front dynamics and how it influences the freezing process of a single red blood cell. The numerical calculation has been modeled in the framework of the phase field method with a Cahn–Hilliard formulation of a free energy functional.

The results show an influence scale on directional phase front propagation dynamics and how significant are stochastic thermal noises in micro-scale freezing.

The numerical calculation has modeled in the framework of the phase field method with a Cahn–Hilliard formulation of a free energy functional.

Based on the brief historical review, the purpose of this paper is to expound the target and bottom line for the farmland institutional reform of in China, analyze the “Chinese scenes” and historical heritage of farmland institutional arrangement, evaluate the policies and their effects over the last four decades and outline the keynotes and possible direction of the future reform.

The paper builds the analytical clue of “institutional target – institutional heritage – policy effort – realistic dilemma – future direction” and review and forecast the Chinese farmland institutional reform.

The farmland institution is an important issue with Chinese characteristics. Over the last four decades, the farmland institutional reform in China has focused on “stabilizing the land property rights” and “promote the farmland transfer.” As the study indicates, the promotion of farmland transfer has not effectively improved the scale economy of agriculture and stabilizing land property rights by titling may restrain the development of farmland transfer market because farmland transfer is of special market logic.

It depends on the revitalization of farmland management rights to resolve the transaction constraint of personal property and its endowment effect in farmland transfer. And, classifying the land management property to involve farmers into the economy of division can be reference for the reform of traditional agriculture worldwide.

With the increased speed and mileage of high-speed lines, the problem of rail wear is increasing. In actual operation, a large number of abnormal wear phenomena occur on both vehicles and rails during fixed line operation; therefore, the purpose of the study is to explored the rail wear for a variety of vehicles running in mixed operation.

This paper used the universal mechanism multibody dynamics software to establish the CRH2 high speed train (HST) and the CRH3 HST vehicle dynamic models, respectively. The mixed running of HSTs on the effect of rail wear evolution law was analyzed. The rail wear of the two vehicles with different curve radii, different wheel diameters and different under-rail stiffness was compared and analyzed.

The result showed that the rail wear of CRH3 HST is greater than that of CRH2 HST. The rail wear in the tangent track under mixed operation conditions is 25.4% less than when CRH3 HST operated independently. When there is a 1-mm wheel diameter difference, the maximum rail wear of CRH2 HST and CRH3 HST increases by 263% and 44%, respectively. The amount of rail wear is proportional to the under-rail stiffness, and the position of the maximum wear is almost unchanged.

Most studies on the evolution law of rail wear are conducted for a single vehicle type and a single line. This study explored the mixed running of HSTs on the effect of rail wear evolution law.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-08-2023-0276/

The paper aimed to summarize innovative rules of Chinese manufacturing enterprises, and put forward some insights in optimal allocation of innovation resources and enhancing the capability of indigenous innovation, so as to overcome the innovation dilemma.

Having diagnosed the current research of innovation flows, the authors defined the concept and stated characteristics of mainstream and new‐stream innovation. Innovation life cycle theory and technology trajectory theory were used to map two evolution patterns of mainstream and new‐stream innovation. It took weeks to stay in firms to obtain original data and interview managers, engineers, and mechanists. From the case study the authors proposed the improvement projects and opportunities for firms to overcome the “innovation dilemma”.

In the indigenous innovation process, enterprises should breed new‐stream innovation as they strengthen the mainstream innovation, view the new‐stream technology as the innovation direction, and fulfill the constant innovation in the convergent innovation and replace evolution process. Meanwhile, enterprises should take precautions both to expand and develop, and fulfill technology transition and innovation upgrade through convergent innovation. Furthermore, firms' convergent innovation, which will finally achieve the “projects‐talents‐products‐markets” collaborative innovation, should be clear about target market and project‐oriented, take the product as the carrier, and be committed to cultivate creative talents and innovative teams.

This paper enriches the existing theory on indigenous innovation by introducing the new concept of mainstream and new‐stream innovation. The findings would help firms to jump out from the innovation morass.

The functionality and reliability of an overhauled aero-engine is determined by all configuration changes in the overhaul process. Identifying, recording, auditing, tracking and tracing of configuration modifications are significant and meaningful. Considering the barriers to these goals, this paper aims to put forward an approach to configuration management in the aero-engine overhaul process.

The overhaul configuration management model is proposed to describe an aero-engine’s configuration evolution trajectory in the overhaul process. The controlling and auditing procedures are put forward to control and audit parts’ return-to-zero statuses and overproof statuses. And some searching algorithms are also designed to enable tracking and tracing of the configuration status along the time coordinate, or get a snapshot of an aero-engine’s configuration at a certain time. The above model, procedures and algorithms have been implemented and adopted to fulfill the configuration management requirements in the aero-engine overhaul process.

The approach is effective in identifying, recording, controlling, auditing, tracking and tracing configuration changes in the overhaul process.

The approach’s implementation and adoption present a practical example for aero-engines’ configuration management issue in the overhaul process.

The work proposes an original aero-engine configuration management solution for the overhaul process and enables a reliable and accurate configuration management mode.

Active contour can describe target's silhouette accurately and has been widely used in image segmentation and target tracking. Its main drawback is huge computation that is still not well resolved. The purpose of this paper is to optimize the evolving path of active contour, to reduce the computation cost and to make the evolution effectively.

The contour‐evolution process is separated into two steps: global translation and local deformation. The contour global translation and local deformation are realized by average and normal gradient flow of the evolving contour curve, respectively.

When a contour is far away from the object to be segmented or tracked, the effective way of contour evolution is that it moves to the object without deformation first and then it deforms into the shape of the object when it moves on the object.

The method presented in this paper can optimize the curve evolving path effectively without complicated calculation, such as rebuilding a new inner product, and its computation cost is largely reduced.

This study aims to advance two sets of explanation on the evolution of corporate social responsibility (CSR) – one set of explanation in the context of a developed country, USA, and another in the context of a developing country, India. The discussion includes the period after mandatory CSR rules were implemented in India.

This is a conceptual paper on the historical evolution of CSR in the USA and India. It reviews the chronological evolution of CSR. It compares the phases of CSR evolution between the two countries by tracking their CSR growth curves.

This study divides the evolution of CSR in the USA into four phases – conceptualization, introduction, growth and consolidation. In the first two phases, the rate of growth in CSR increases at a decreasing rate; in the growth phase, it increases at an increasing rate which stabilizes in the consolidation phase. In the Indian context, the study considers a three phase growth – conceptualization, introduction and growth. In the first two phases, the growth in CSR curve is inelastic. In the third phase, the growth rate increases but at a rate less than that in the USA.

Though past research has examined historical evolution of CSR in the US context, scant research has tracked CSR evolution in India. Not many studies have compared the growth of CSR between developed and developing countries. This study also contributes the concept of CSR growth curves to the extant literature on CSR.

The purpose of this paper is to solve difficult estimation problem on aircraft sudden fault by proposing a new pre-estimating method according to the energy evolution degree of the sensitive parameters to estimate the sudden fault. The sudden fault affects seriously the flight safety of aircraft.

It is based on the dissipative structure theory, and the evolution process of energy parameters is utilized. First, the evolution key points of sudden fault are determined by the time-varying entropy of sensitive parameters and the frequency band energy distribution. Then, we can obtain the evolution degree of sample while the evolution key points import the logistic regression (LR) model, and one can establish the pre-estimation model by means of relevance vector machine (RVM). While the evolution feature vector imports the RVM pre-estimation model, one can pre-estimate the sudden fault of aircraft.

The simulation results showed that this method can not only track the evolution process of aircraft sudden fault but also estimate its evolution degree, and it has a higher pre-estimating accuracy.

It provides a new way to forecast the sudden fault and increase the security of aircraft.

This paper proposes a pre-estimating method on aircraft sudden fault. It is based on the dissipative structure theory and the energy-sensitive parameters of the sudden faults are used. This method can enhance the security of aircraft and increase the protective ability of sudden fault on aircraft.