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The paper aims to find the correlation between the microparameters and the macroparameters of the soil. The study aims to calibrate the macroscale and microscale parameters of rolling resistance contact models to successfully apply the discrete element method to do some research of the geotechnical problem.

The paper opted for an exploratory study using the PFC3D to simulate the triaxial tests that include more than 50 cases and the coupling analysis method, which considering several effect of various factors.

The paper provides a quantitative relationship between the macroparameters and microparameters of the rolling resistance linear model and a method for fast calibration of macroscopic parameters is proposed and verified by a triaxial test example.

This paper provides the quantitative relationship of micro and macroparameters in the rolling resistance linear model by studying a single factor and considering the coupling effect of various factors and a fast method for the calibration of microparameters based on the rolling resistance linear model is proposed.

To understand the service performance of full ceramic ball bearings under extreme working conditions and improve their service life, dynamic characteristic tests of full ceramic ball bearings under ultra-low temperature conditions were carried out by a low-temperature bearing life testing machine, and temperature rise and friction were measured under extreme low-temperature environment.

The heat-flow coupling model of bearing was established by CFD software, and the test results were further analyzed.

The results show that the temperature rise of the bearing is not obvious in the liquid nitrogen environment. With the increase of the chamber temperature, the lubrication state of the bearing changes, resulting in the temperature rise of the outer ring of the bearing. As the temperature of the test chamber increases, the friction force on the bearing increases first and then decreases under the action of multifactor coupling.

The research results provide test data and theoretical basis for the application of all-ceramic ball bearings in aerospace and other fields and have important significance for improving the service life of high-end equipment under extreme working conditions.

The research results provide test data and theoretical basis for the application of full ceramic ball bearings in aerospace and other fields and have important significance for improving the service life of high-end equipment under extreme working conditions.

The research results provide test data and theoretical basis for the application of full ceramic ball bearings in aerospace and other fields and have important significance for improving the service life of high-end equipment under extreme working conditions.

The research results provide test data and theoretical basis for the application of full ceramic ball bearings in aerospace and other fields and have important significance for improving the service life of high-end equipment under extreme working conditions.

The adoption of enterprise resource planning (ERP) systems is a major challenge to organizations. Many implementation teams struggle to ensure the success of such projects. The information systems literature indicates that the team attributes of breadth of experience, empowerment, and cohesion are necessary conditions for project success. This paper aims to investigate how the nature of implementation teams may affect adoption success.

The research employs a positivist, qualitative field study approach to investigate the role of the implementation team attributes in ERP system adoption. Project success is assessed on three determinants, i.e. support of organizational activities, stakeholder satisfaction, and system acceptance.

The findings provide new insights as to the extent to which prior assumptions from the information systems literature apply in the ERP system implementation context. The results indicate that team empowerment and cohesion are not necessary precursors to project success as their impact depends on the adoption context.

The circumstances under which the impact of low team empowerment and low cohesion can be alleviated in ERP adoption projects are discussed.

The paper offers explanations as to why certain established assumptions regarding information systems teams and project success may not apply to an ERP adoption context.

The purpose of the present work is to study the impacts of rapid cooling and Tb rare-earth additions on the structural, thermal and mechanical behavior of Bi–0.5Ag lead-free solder for high-temperature applications.

Effect of rapid solidification processing on structural, thermal and mechanical properties of Bi-Ag lead-free solder reinforced Tb rare-earth element.

The obtained results indicated that the microstructure consists of rhombohedral Bi-rich phase and Ag99.5Bi0.5 intermetallic compound (IMC). The addition of Tb could effectively reduce the onset and melting point. The elastic modulus of Tb-containing solders was enhanced to about 90% at 0.5 Tb. The higher elastic modulus may be attributed to solid solution strengthening effect, solubility extension, microstructure refinement and precipitation hardening of uniform distribution Ag99.5Bi0.5 IMC particles which can reasonably modify the microstructure, as well as inhibit the segregation and hinder the motion of dislocations.

It is recommended that the lead-free Bi-0.5Ag-0.5Tb solder be a candidate instead of common solder alloy (Sn-37Pb) for high temperature and high performance applications.

The purpose of this study is to corroborate the advanced tribological properties of graphene as a lubricant additive.

Different concentrations of functionalized graphene were coated on the substrate surface. Tribological properties of the graphene lubricants were carried out by ball-on-disk tribology tests. Wear mechanism of functionalized graphene was studied by observing wear scars on the substrate surface. Finally, the wear resistance of modified graphene was calculated by calculating and analyzing the applied experimental conditions and the obtained experimental data.

The best concentration of graphene lubricant is 0.5 wt.% which shows the best tribological performance. And the coefficient of friction is 0.08. Compared with the dry friction condition, the coefficient of friction and wear rate of best graphene lubricant decreased by 80% and 82%.

The formula of graphene lubricant is independently developed and works very well. Graphene lubricant can prevent the substrate from oxidation. The thickness of the graphene lubricant is about 4-7µm. The concept of anti-wear strength was introduced in this paper. When 0.5 Vol.% graphene was added, the anti-wear strength was greatly improved from 115.3 kg·mm-2 to 657.6 kg·mm-2.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-08-2019-0344

Strategic management research has shown growing interest in understanding the dynamic resource reconfiguration processes through which firms grow, evolve, and sustain profitability. The goal of our study is to understand how dynamic resource reconfigurations enable firms to pursue growth opportunities. We use the methods of inductive theory building from case studies to elaborate current theoretical understanding about how firms draw on both internal and external resources in the pursuit of growth. We examine the patterns of resource reconfigurations through which Yahoo and Google powered their early growth strategies in their first 10 years of existence. We analyze a total of 192 new product launches in 43 markets by the two firms to capture how they reconfigured resources dynamically. Our analysis reveals that both firms developed highly dynamic strategies exhibiting both surprising similarities and differences. These similarities and differences provided the basis for our theoretical insights about the development of what we term “dynamic resource platforms,” comprising of (a) dynamic resource shifts; (b) targeted resource orchestration; and (c) complementary processes balancing dynamism and capability development. These ideas contribute novel theoretical insights to current strategic management research on dynamic capabilities and on resource reconfiguration and redeployment.

Strategy scholars have theorized that a firm's strategic leaders play an important role in firm dynamic capabilities (DCs). However, little research to date has studied how leaders shape the development of DCs. This inductive theory-building study sheds new light on the multilevel architecture of DCs by uncovering that the three core DCs – sensing, seizing, and reconfiguring – operate through distinct individual, group, and organizational processes. Further, the role of strategic leadership is critical as organizational processes create DCs only when they are purposefully designed by firms' strategic leaders to enable change and opportunity pursuit. Whether strategic leaders design processes for change and opportunity pursuit, in turn, reflects the extent to which they view change as positive and desirable. Our insights about the role of strategic leaders' positive attitude toward change as an important aspect of firm DCs uncover new interconnections between strategic leadership, organizational design, and the micro-foundations of DCs. Collectively our findings about the role of positive attitude toward change, the purposeful design of processes for change, and the varying manifestations of these processes at different levels of analysis reveal the coupling of strategic and organizational processes in enabling strategic dynamism and change.

Scholars typically view cross-legacy boundary spanners – employees who develop and maintain social relationships with coworkers from both legacy organizations – as the key integrators in mergers and acquisitions (M&As). Organizations even formally appoint employees with cross-legacy responsibilities to support the post-merger integration process. Recent research has started to emphasize, however, how difficult it can be to reap the benefits of a boundary-spanning position. Building and maintaining formal or informal boundary-spanning ties is costly because it requires time, attention, and political savviness. To better understand the perks and pitfalls of cross-legacy boundary-spanning, the authors identify and describe its structural and sociocultural dimensions and explain how they influence cross-legacy boundary-spanning in M&A contexts. The authors argue that the two dimensions can be seen as boundary conditions to the positive relationship between cross-legacy boundary spanning and post-merger integration. This chapter highlights the potential dark side of cross-legacy boundary-spanning and proposes a multi-dimensional model to explain how cross-legacy boundary spanners can avoid the pitfalls and promote the perks of their position in support of successful post-merger integration.

To improve the efficiency, accuracy and adaptivity of the parameter inversion analysis method of a rockfill dam, this study aims to establish an adaptive model based on a harmony search algorithm (HS) and a mixed multi-output relevance vector machine (MMRVM).

By introducing the mixed kernel function, the MMRVM can accurately simulate the nonlinear relationship between the material parameters and dam settlement. Therefore, the finite element method with time consumption can be replaced by the MMRVM. Because of its excellent global search capability, the HS is used to optimize the kernel parameters of the MMRVM and the material parameters of a rockfill dam.

Because the parameters of the HS and the variation range of the MMRVM parameters are relatively fixed, the HS-MMRVM can imbue the inversion analysis with adaptivity; the number of observation points required and the robustness of the HS-MMRVM are analyzed. An application example involving a concrete-faced rockfill dam shows that the HS-MMRVM exhibits high accuracy and high speed in the parameter inversion analysis of static and creep constitutive models.

The applicability of the HS-MMRVM in hydraulic engineering is proved in this paper, which should further validate in inversion problems of other fields.

An adaptive inversion analysis model is established to avoid the parameters of traditional methods that need to be set by humans, which strongly affect the inversion analysis results. By introducing the mixed kernel function, the MMRVM can accurately simulate the nonlinear relationship between the material parameters and dam settlement. To reduce the data dimensions and verify the model’s robustness, the number of observation points required for inversion analysis and the acceptable degree of noise are determined. The confidence interval is built to monitor dam settlement and provide the foundation for dam monitoring and reservoir operation management.

Resource reconfiguration enables firms to adapt in dynamic environments by supplementing, removing, recombining, or redeploying resources. Whereas prior research has underscored the merits of resource reconfiguration and the modes for implementing it, little is known about the antecedents of this practice. According to prior research, under given industry conditions, resource reconfiguration is prompted by a firm’s corporate strategy and by characteristics of its knowledge assets. We complement this research by identifying learning from performance feedback as a fundamental driver of resource reconfiguration. We claim that performance decline relative to aspiration motivates the firm’s investment in knowledge reconfiguration, and that this investment is reinforced by the munificence of complementary resources in its industry, although uncertainty about the availability of such resources limits that investment. Testing our conjectures with a sample of 248 electronics firms during the period 1993–2001, we reveal a clear distinction between exploitative reconfiguration, which combines existing knowledge elements, and exploratory reconfiguration, which incorporates new knowledge elements. We demonstrate that performance decline relative to aspiration motivates a shift from exploitative reconfiguration to exploratory reconfiguration. Moreover, munificence of complementary resources mitigates the tradeoff between exploratory and exploitative reconfigurations, whereas uncertainty weakens the motivation to engage in both types of reconfiguration, despite the performance gap. Nevertheless, codeployment, which extends the deployment of knowledge assets to additional domains, is more susceptible to uncertainty than redeployment, which withdraws those assets from their original domain and reallocates them to new domains. Our study contributes to emerging research on resource reconfiguration, extends the literature on learning from performance feedback, and advances research on balancing exploration and exploitation.