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This paper aims to develop a parallel fast neighbor search method and communication strategy for particle-based methods with adaptive smoothing-length on distributed-memory computing systems.

With a multi-resolution-based hierarchical data structure, the parallel neighbor search method is developed to detect and construct ghost buffer particles, i.e. neighboring particles on remote processor nodes. To migrate ghost buffer particles among processor nodes, an undirected graph is established to characterize the sparse data communication relation and is dynamically recomposed. By the introduction of an edge coloring algorithm from graph theory, the complex sparse data exchange can be accomplished within optimized frequency. For each communication substep, only efficient nonblocking point-to-point communication is involved.

Two demonstration scenarios are considered: fluid dynamics based on smoothed-particle hydrodynamics with adaptive smoothing-length and a recently proposed physics-motivated partitioning method [Fu et al., JCP 341 (2017): 447-473]. Several new concepts are introduced to recast the partitioning method into a parallel version. A set of numerical experiments is conducted to demonstrate the performance and potential of the proposed parallel algorithms.

The proposed methods are simple to implement in large-scale parallel environment and can handle particle simulations with arbitrarily varying smoothing-lengths. The implemented smoothed-particle hydrodynamics solver has good parallel performance, suggesting the potential for other scientific applications.

This paper aims to investigate the effects of reciprocating frequency, large normal load on friction and wear behavior of hydrogenated diamond-like carbon (H-DLC) coating against Ti-6Al-4V ball under dry and lubricated conditions.

The friction and wear mechanisms are analyzed by scanning electron microscope, energy dispersive spectroscopy and Raman spectroscopy.

The results show that as reciprocating frequency increases under lubricated conditions, the friction coefficient decreases first and then increases. When the reciprocating frequency is 2.54 Hz, the value of friction coefficient reaches the minimum. The friction reduction is because of the transformation from sp³ to sp², the formation of transfer layer on Ti-6Al-4V ball and the reduction in viscous friction, whereas the increase of friction coefficient is related to wear. In dry conditions, the friction coefficient is between 0.06 and 0.1. And, the service life of H-DLC coating decreases with the increase in reciprocating frequency and normal load.

It is confirmed that adding the lubricant could prolong the service life of H-DLC coating and reduce friction and wear efficiently. And, the wear mechanisms under dry and lubricated conditions encompass abrasive wear and adhesive wear.

The results are helpful for application of diamond-like carbon coating.

The National People’s Congress (NPC) of People’s Republic of China, the highest organ of state power, is popularly seen as a rubber-stamp entity. However, it has been substantially evolving its roles to accommodate the governance discourses within China’s political system over the decades. This study aims to explore the changes of governance discourse of the NPC within China’s political system through which to offer a thorough understanding of the NPC’s evolving substantial role in current China.

This study deploys a historical approach to explore the changes of governance discourse of the NPC that has seen a growing importance in China’s political agenda, as argued by this study.

The authors find that the NPC has been substantially evolving its role within China’s political system in which the Chinese Communist Party has created different governance discourses. Besides, the NPC and its Standing Committee have asserted its authority as a substantial actor within China’s political system. The NPC is no longer functioned as a rubber-stamp institution, though it is still popularized as a rubber stamp by many scholars.

This study is a historical elaboration on the development of NPC under three governance discourses. It might be, to some extent, relatively descriptive in nature.

This study, therefore, sheds some light on a revisit on the governance discourses in current China.

This paper aims to investigate the electrochemical corrosion behavior of a five-layer Al alloy composites (4343/4047/3003/4047/4343) with a thickness of 0.2 mm in NaCl solution.

Electrochemical impedance spectroscopy, polarization curve and morphology analyses were used to study the corrosion behavior of the Al alloy composites from cross-sectional and plane directions.

The corrosion resistance of the surface from the plane direction was higher than that from the cross sections. Si-enrich particles were observed in the outer 4047/4343 layer, and AlFeCuMnBi phases were identified in the core 3003 layer. The galvanic coupling between the Si-enrich particle and the Al matrix accelerated the dissolution Al matrix.

This work lays the experimental foundation for corrosion mechanism of the Al alloy composite plate.

Accounting scandals and earnings management problems at large firms such as Global Crossing and Enron have resulted in lots of wealth loss not only to corporate investors but also led tremendous damage to societies. Hence, policymakers and academic researchers have started to explore mechanisms to prevent improprieties in financial reporting and further enhance firm value. Using data from United States (US)-listed companies between 2000 and 2018, this article explores the effect of ex-military executives on earnings quality, the role of financial analysts in their interplay and the firm value implication of earnings quality driven by ex-military executives.

This study employs a firm fixed-effects model to validate the main conjecture and adopts the weighted least squares, Granger causality analysis, instrumental variable approach, propensity score matching, entropy balancing approach and dynamic system Generalized Method of Moments (GMM) estimator to address robustness and endogeneity issues.

Authors reveal that companies run by ex-military senior executives exhibit lower levels of accruals-based and real earnings management than those without. The effect of management military leadership on constraining earnings management is more prominent for companies with low analyst coverage, suggesting that the military experience of executives could be a substitute for external monitoring. Authors also find that these ethical managers alleviate the negative impact of earnings management on firm value and that companies managed by these managers exhibit higher firm performance.

This study highlights the importance of the intrinsic motivation behind the effect of military experience on senior managers' personalities and offers essential stakeholder-related implications regarding the effect of military experience. The military experience of senior managers helps facilitate the attainment of broader corporate governance and economic objectives.

This article adds new insights to the literature on the role of managerial military experience in decision-making processes, financial reporting outcomes and firm performance by employing the upper echelons and imprinting theoretical perspectives.

Suggests that misunderstandings frequently occur when trying to understand Chinese language and culture, and so gives the implied meaning of various Chinese expressions and sayings such as greetings, thanks, respect, age, congratulations and taboo subjects.

The purpose of this paper is to apply what can be learned from the emergence of nature tourism to understand some current and future trends of tourism.

This study adopted the evolutionary paradigm for investigation.

The emergence of nature tourism in early medieval China can be attributed to four major factors, including transformation of value orientations, seeking longevity, interest in suburbs and population migration.

Historical studies help understand the current and future trends. When the contributing factors for nature tourism are linked to the contemporary world, it can be found that these factors are still playing a part in shaping tourism trends or patterns in their original or alternative forms. These trends or patterns are worthy of scholarly investigations.

This paper offers a comprehensive understanding of the origins of nature tourism.

Purpose of study: Indian fibre cement industry is at crossroads on account of the dropping margins attributed to the dynamic internal and external challenges faced by it. The ever-changing technology, the increasing availability of substitutes and changing demographic consumption profiles have questioned the survival of this industry. Internal and external factors affecting an organization provide inputs to the strategic decision-making. Diversity of factors and prioritization is a major challenge encountered for developing a strategy for the organization.

Strategic analysis in the paper proposes to rank important key variables through SWOT-AHP methodology affecting a fibre cement company. Computed priorities of SWOT factor could help in formation of management approach to key decisions facing the firm. It is a descriptive research design. The problem itself has multiple SWOT criteria that have been evaluated in three phases with the help of industry experts and AHP criteria.

SWOT-AHP analysis has been a strategic fit for qualitative analysis of factors. The important ranked factors affecting the organization have been found to be brand name, capability of both the management and technical, quality of the product, and the efficient customer service and marketing reach/distribution.

Ranking of key SWOT factors found through AHP methodology will help the firm under study to develop and plan strategic alternatives to counter all challenges faced by them.

The management of the firm under study shall be benefited in fine-tuning the overall strategy of the organization.

This paper proposes a hybrid SWOT-AHP strategic analysis first time in this sector. The affecting factors have been quantified and ranked to identify priority factors for the firm to focus.

In high-speed processing, the influence on the machining accuracy of a machine tool is greatly caused by the thermal deformation of the motorized spindle; a further study on the thermal characteristics of the spindle is given in this paper. This study aims to reduce the thermal error and improve the performance of the machine tool by discussing the relationships between the temperature distributions and rotating accuracy caused by the thermal deformations of the spindle.

The paper opted for a method combining the theoretical analysis and the experimental study to study the thermal stability of the high-speed motorized spindle. First of all, a finite element model of the spindle was built with ANSYS, whereby temperature distributions and the thermal deformations were successively obtained at different speeds. And then, both the temperature field and the rotating accuracy of the motorized spindle were measured simultaneously by the thermal stability experiment. Finally, the experimental and theoretical results were compared and validated.

The thermal stability of the motorized spindle was studied in this paper, and some findings from the study were as follows: the spindle’s rotating accuracy maintained good in X direction but bad in Y and Z directions in terms of the deformations; the higher front-end temperature of the spindle which can significantly affect the rotating accuracy is needed to be controlled mainly; the recovery speed of the spindle deformation lagged behind the temperature’s fallback speed; the vibration graph about radial rotating sensitivity synthesized by X1 and X2 presented a trifoliate shape.

Based on a built test-bed which can synchronously measure the motorized spindle’s temperature distribution and rotating accuracy with five-point method, the coupling effects of the thermal deformation and temperature are embodied, and not only the vibration graph but also the thermal tilt angles can be gained. Therefore, considering the influence of the thermal deformation on the heat generated by the bearings, the paper fulfilled a study by which it was obtained that the front-end temperature of the spindle, which was higher and could significantly affect the rotating accuracy, needed to be controlled mainly.