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The purpose of this paper is to study the interaction of main marine organisms on localized corrosion of 316L stainless steel in the Dalian Sea area.

The steel plate was immersed in the Dalian Sea area for nine months to observe the biofouling and localized corrosion. The local potential distribution on the steel plate covered by marine organisms was measured. The local electrochemical measurements were performed to facilitate understanding the interfacial status under different biofouling conditions. The local surface morphologies and corrosion products were characterized.

The localized corrosion of stainless steel is mainly induced by the attachment of barnacles on the steel. The mussels have no influence on the localized corrosion. The cover of sea squirts could mitigate the localized corrosion induced by barnacles. Both crevice corrosion and pitting corrosion were found beneath the barnacle without the covering of sea squirts. The pitting damage was more serious than the crevice corrosion in the Dalian Sea area. The probing of sulfur element indicates that the potential growth of sulfate-reducing bacteria at barnacle center.

The above findings revealed that the interaction of marine organisms has significant influences on the localized corrosion of stainless steel. The influences of macro-fouling and micro-fouling on localized corrosion are discussed.

Customer service is crucial for organizations' survival and competitiveness in the hospitality industry. The purpose of this study is to examine how and when servant leadership affects extra-role customer service.

The hypotheses were tested with a sample of 302 employees from a passenger transport company in China.

Results demonstrate that servant leadership was positively related to extra-role customer service and that this relation was mediated by relational identification. In addition, the mediating effect of relational identification in the relation between servant leadership and extra-role customer service was contingent on prosocial motivation.

The study is the first to explore the relation between servant leadership and extra-role customer service from the perspective of relational identification and the moderating role of prosocial motivation.

The purpose of this paper is to describe a local melt process of solder bumping employed in electronic packaging applications by an induction heating reflow method, for a combined numerical and experimental study involving a temperature measurement using an infrared thermometer during the reflow process and microstructural observations after reflow, which can be used to control the height and shape of solder interconnects.

In the induction heating reflow process, the temperature distribution within the solder ball during the heating phase is of prime importance for the success of the process and the geometry control quality of final joints. This paper investigates the local melt process of solder balls reflowed onto Cu/Ni/Au pads, and focuses on the effect of the inductive heat on the thermal distribution during the melting process. A finite‐element model is applied to simulate the thermal field in a solder bump during the induction heating period in a reflow process. The effects of the coil current and the electromagnetic frequency on the thermal performance are investigated by using the validated thermal model. The local melt phenomenon in the solder joint is observed and identified by the microstructures taken using scanning electron microscopy.

In this paper, the numerical results match the experimental results quite well to validate the finite element modeling model. The local melt phenomenon predicted by simulation, and verified by experiments, is demonstrated to be capable of controlling the solder joint shape. Several parametric studies are carried out to understand the effects of different frequencies during assembly, and to suggest that a higher frequency is easier to get a greater temperature gradient, thus a more obvious local melt phenomenon, which is good for achieving the geometry control for solder joints.

The findings of this paper will help to understand the detailed solder bumping process during induction heating reflow and the effects of electromagnetic field frequency on solder joint shape controlling.

The aim of the paper is to control the height and shape of solder interconnects employed in electronic packaging applications by an induction heating reflow method, which can achieve the solder bumping and interconnecting process in a simple way.

Through the application of a designed induction heating system, a new methodology was forced to exhibit its certain qualities of forming and geometry controlling in the process. The corresponding temperature distribution has been analyzed based on a discussion of skin effects in metal spheres. The local melt phenomenon is observed and identified via the microstructures taken by scanning electron microscope (SEM).

In this work, barrel‐shaped solder joints with high heights and hourglass‐shaped solder joints can be obtained, which is good for improving the solder joint lifetime. The mechanism of solder joint height and shape control, which can be explained by the local melt phenomenon, is discussed and demonstrated via the different morphologies of Ag₃Sn intermetallic compound (IMC).

The findings of this paper will help the understanding of the whole solder interconnecting process during induction heating reflow and the effects of electromagnetic fields on solder joint shape control.

In the high-speed trains (HSTs) production process, assembly sequence planning (ASP) problems is an extremely core issue. ASP problems influence the economic cost, amount of workers and the working time in the assembly process, seriously. In the design process of HSTs, the assembly sequence is usually given by experience, and the correctness of the assembly sequence is difficult to guarantee by experience and low effectiveness. The ASP based on improved discrete particle swarm optimization (IDPSO) algorithm was proposed to address these issues.

In view of the local convergence problem with basic DPSO in ASP, this paper presents an IDPSO, in which a chosen strategy of global optimal particle is introduced in, to solve the ASP problems in the assembly process of HSTs operation panel. The geometric feasibility, the assembly stability, and the number of assembly orientation changes of the assembly are chosen to be the optimization objective. Furthermore, the influences of the population size, the weight coefficient, and the learning factors to the stability and efficiency of IDPSO algorithm were discussed.

The results show that the IDPSO algorithm can obtain the global optimum efficiently, which is proved to be a more useful method for solving ASP problems than basic DPSO. The IDPSO approach could reduce the working time and economic cost of ASP problems in HSTs significantly.

The method may save the economic cost, reduce the amount of workers and save the time in the assembly process of HSTs. And also may change the method of ASP in design and manufacturing process, and make the production process in HSTs more efficiently.

A chosen strategy of global optimal particle is presented, which can overcome the local convergence problem with basic DPSO for solving ASP problems.

This paper aims to effectively achieve endmembers and relative abundances simultaneously in hyperspectral image unmixing yield. Hyperspectral unmixing, which is an important step before image classification and recognition, is a challenging issue because of the limited resolution of image sensors and the complex diversity of nature. Unmixing can be performed using different methods, such as blind source separation and semi-supervised spectral unmixing. However, these methods have disadvantages such as inaccurate results or the need for the spectral library to be known a priori.

This paper proposes a novel method for hyperspectral unmixing called fuzzy c-means unmixing, which achieves endmembers and relative abundance through repeated iteration analysis at the same time.

Experimental results demonstrate that the proposed method can effectively implement hyperspectral unmixing with high accuracy.

The proposed method present an effective framework for the challenging field of hyperspectral image unmixing.

The purpose of this paper is to fill important gaps by using the attachment theory and examining the effects of supervisors’ early family environment on their behaviors toward subordinates and subordinates’ responses.

The authors used samples of 334 supervisor–subordinate pairs from a manufacturing company.

The study finds that supervisors’ harmonious family environment has a positive influence on subordinates’ responses (job satisfaction, work-to-family enrichment and task performance) through the effect of supervisors’ positive working model and caregiving behavior. On the contrast, supervisors’ conflicting family environment has a negative influence on subordinates’ responses through the effect of supervisors’ negative working model and aggressive behavior.

Existing studies mainly explore the influence of organizational environment on supervisors’ treatment of their subordinates. However, few have examined the relationship between supervisors’ early family environment and their treatment of their subordinates.

The purpose of this study is to set up a dynamic model of material extrusion (ME) additive manufacturing plates for the prediction of their dynamic behavior (i.e. dynamic inherent characteristic, resonant response and damping) and also carry out its experimental validation and sensitivity analysis.

Based on the classical laminated plate theory, a dynamic model is established using the orthogonal polynomials method, taking into account the effect of lamination and orthogonal anisotropy. The dynamic inherent characteristics of the ME plate are worked out by Ritz method. The frequency-domain dynamic equations are then derived to solve the plates’ resonant responses, with which the damping ratio is figured out according to the half-power bandwidth method. Subsequently, a series of experimental tests are performed on the ME samples to obtain the measured data.

It is shown that the predictions and measurements in terms of dynamic behavior are in good agreement, validating the accuracy of the developed model. In addition, sensitivity analysis shows that increasing the elastic modulus or Poisson’s ratio will increase the corresponding natural frequency of the ME plate but decrease the resonant response. When the density is increased, both the natural frequency and resonant response will be decreased.

Future research can be focused on using the proposed model to investigate the effect of processing parameters on the ME parts’ dynamic behavior.

This study shows theoretical basis and technical insight into improving the forming quality and reliability of the ME parts.

A novel reliable dynamic model is set up to provide theoretical basis and principle to reveal the physical phenomena and mechanism of ME parts.