Search results

We examined the role gender plays in managerial stereotypes and changes that have occurred in the US for executive women in the workforce. We also investigated factors and personality traits that affect advancement into upper management for all executives and those that affect women in particular. Despite increased organisational sensitivity, public policies, and equal rights legislation, women continue to be underrepresented in corporate America. Pay increases and promotions for females have not kept pace with those for men. Study results also indicate that managerial womenwho juggle jobs and family life benefit from these multiple roles, but women who put off marriage and family to build top‐level careers suffer in later years from greatly reduced chances of finding spouses and having children. Further adaptation of organisational culture in the new economy, weakening of the glass ceiling phenomenon, and family friendly work policies may alleviate some of the difficulties experienced by women who want it all.

This article has been withdrawn as it was published elsewhere and accidentally duplicated. The original article can be seen here: 10.1108/02610150310787351. When citing the article, please cite: Dean Elmuti, Judith Lehman, Brandon Harmon, Xiaoyan Lu, Andrea Pape, Ren Zhang, Terad Zimmerle, (2003), “Inequality between genders in the executive suite in corporate America: moral and ethical issues”, Equal Opportunities International, Vol. 22 Iss: 2, pp. 40 - 58.

In China, external supervision on construction safety mainly comes from the government and supervision engineers (SEs). However, the construction safety supervisory mechanism (CSSM) contains some dilemmas affecting the improvement of safety performance, such as the declining impact of SEs, the increasing rent-seeking behaviors of contractor and excessive government interference. This study aims to depict and analyze the CSSM in China from an evolutionary game view. The objectives are to understand the supervision strategy and evolutionary behaviors of different stakeholders, propose suggestions for improving safety performance and help the key safety supervision stakeholders, especially the government, formulate a suitable safety supervision strategy.

This research uses tripartite dynamic evolutionary game theory to study the CSSM in China and solve the stable equilibrium solution using system dynamics.

This study has revealed the game relationship of construction safety supervision mechanisms in China and solved the stable equilibrium solution. The results prove that a supervision engineer (SE) plays a crucial role in the CSSM, and “supervision engineer useless” is an unreasonable assertion. For government supervision agency (GSA), excessive inspection and free-market regulation are neither wise strategies. GSA can reduce the inspection frequency when general contractors (GCs) input high safety investments and SEs implement responsible supervision. But keeping proper government supervision to avoid GC's unlawful behaviors and SE's rent-seeking is indispensable. In addition, excessive governmental supervision will weaken SE's role, so the government should transfer some supervision powers to SE.

This study focuses on the dynamic evolution process between GSA, GC and SE. This method is different from most research that neglected the dynamic characteristic of system and game solution stability. The research methods not only contribute to construction safety supervision policy-making in China but also help to improve supervision efficiency in other countries and other fields.

Reducing employees’ knowledge hiding is vital for enterprise managers. The development of enterprise social media brings opportunities for them to manage employees’ knowledge-hiding behaviors. However, whether the use of enterprise social media inhibits or promotes knowledge hiding is still unclear. The purpose of this study is to explore how enterprise social media usage affect employees' knowledge hiding.

Based on the intrinsic and extrinsic motivation model, this paper proposes a research model to investigate the relationship between enterprise social media usage and knowledge hiding, using a structural equation modeling analysis of 288 employees’ data.

The results show that work-related public social media usage has an inhibiting effect on employees’ knowledge hiding, whereas the effect of work-related private social media usage on employees’ knowledge hiding is not significant; socially related public social media and private social media usage has a promoting effect on employees’ knowledge hiding; and job engagement acts in a positive moderating role between socially related private and public social media usage and evasive hiding.

First, this paper contributes to knowledge-hiding literature by revealing the relationship between enterprise social media usage and knowledge hiding. Second, this study contributes to motivation theory by clarifying how the use of enterprise social media with different motivations affects knowledge hiding. Third, this paper also contributes to knowledge-hiding literature by revealing a boundary condition, namely, job engagement.

With the popularization of permanent magnet linear synchronous machines (PMLSMs) in recent years, the temperature rise has attracted increasingly attention since excessive heat generated in the windings could deteriorate the electromagnetic performance. In order to solve this problem, adopting water-cooled system is an effective method. The purpose of this paper is to investigate a 12-slot/11-pole (12S/11P) water-cooled double-sided PMLSM, which adopts the all teeth wound concentrated winding and shifted armature ends.

Based on 2D finite element analysis (FEA), the thermal performances, such as temperature distribution, the optimization of water flow rate and the influence of demagnetization, are investigated under the condition of continuous duty. Then the maximum current density and average thrust force are calculated for PMLSMs with or without water-cooled system. Finally, the detailed comparison is made between single-sided PMLSM and double-sided PMLSM.

With water-cooled system, the thermal performance of PMLSM can be improved, such as an efficient decrease of temperature rise, restriction of permanent magnet demagnetization and a dramatic increase of the maximum thrust force. It is found that the water flow rate has a significant impact on temperature rise, which can be optimized according to demands.

Electromagnetic and thermal coupled analysis is proposed in this paper. It can approximately predict thermal performance and save the manual iteration time at the same time. This method also can provide as a reference of thermal analysis for other PMLSMs.

Selective laser melting (SLM) is a promising additive manufacturing technology in the field of complex parts’ fabrication. High temperature gradient and residual stress are vital problems for the development of SLM technology. The purpose of this paper is to investigate the influence of substrate characteristics on the residual stress of SLMed Inconel 718 (IN718).

The SLMed IN718 samples were fabricated on the substrates with different characteristics, including pre-compression stress, materials and pre-heating. The residual stress at the center of the top surface was measured and compared through Vickers micro-indentation.

The results indicate that the residual stress reduces when the substrate contains pre-compression stress before the SLM process starts. Both substrate thermal expansion coefficient and thermal conductivity affect the residual stress. In addition to reducing the difference of thermal expansion coefficient between the substrate and the deposited material, the substrate with low thermal conductivity can also decrease the residual stress. Substrate pre-heating at 150°C reduces nearly 42.6 per cent residual stress because of the reduction of the temperature gradient.

The influence of substrate characteristics on the residual stress has been studied. The investigation results can help to control the residual stress generated in SLM processing.

Permanent magnet linear synchronous machines (PMLSMs) have large thrust ripple due to the longitudinal end effect caused by the finite length of the armature compared with rotary machines. The purpose of this paper is to analyze the influence of electric loading on thrust ripple performances based on a 12 slots/14 poles (12S/14P) PMLSM. Furthermore, the method of skewed PMs to reduce thrust ripple is investigated based on multi slices 2D finite element (FE) models.

The thrust ripple of PMLSM under open-circuit condition results from the slotting and the longitudinal end effects. Therefore, periodical model has been designed to clarify the effect of the longitudinal end effect. Under on-load condition, the thrust ripple increases and exhibits an effective component of thrust force. To analyze the thrust ripple under on-load condition, frozen permeability (FP) technique is employed. In addition, the method of skewed PMs is analyzed in this paper to obtain more smooth thrust force performance. The effectiveness of skewing accounting for skew angles, step skew numbers and slot/pole number combinations was highlighted.

The longitudinal end effect dominates the thrust ripple of PMLSM in both cases, i.e., open-circuit and on-load conditions. Under on-load condition, the second harmonic component of thrust ripple related to flux linkage harmonics increases significantly. Moreover, the effectiveness of skewed PMs is largely reduced with the increase of magnetic saturation. At last, a proper skew angle and step skew number are obtained for the conventional PMLSM with fractional-slot winding.

By 60 electrical degrees and two or three step skewed PMs, the thrust ripple can be decreased to a tolerable limite for conventional PMLSM. The thrust ripple harmonics contributed by longitudinal end effect and flux linkage harmonics are analyzed, respectively, which is beneficial to exploring other techniques such as adding end auxiliary teeth to obtain lower thrust force pulsation.

In electric system of high-speed trains, neutral sections are set to balance the three-phase load. When passing neutral sections, the train should detach from the power supply for a short time. To permanent magnet synchronous motors (PMSMs) traction system, the voltage of DC link will increase quickly due to the back-EMF of PMSM during this time. Although the energy consumption braking method can be adopted to consume the feedback energy. It not only wastes energy, but also causes more speed drop of the train. The paper aims to discuss these issues.

In order to get better performance when the train is under passing neutral section condition, a suitable control method is proposed, in which the torque command is set to zero and d-axis current order remains unchanged during passing neutral section. Based on a co-simulation model, the influences of this method on the PMSMs traction system are compared with that of traditional method, which is used in induction motors traction system. This model combines both control strategy and finite element model of motor, which can take the effects of magnetic saturation and power loss into consideration.

In PMSMs traction system, PMSMs work as generators during neutral section, and charge to DC bus, which may cause over-voltage damage. Moreover, there would be strong torque shock at the moment of power cut-off. It is finally found that, with the suitable control method, the high-speed train can pass the neutral section with less speed drop, less torque shock and little DC link voltage rise.

The control method proposed in this paper is easier to achieve and gets a better performance of PMSMs traction system in high-speed train compared with the traditional method. Furthermore, the co-simulation model is much closer to reality than the analytical model.

Due to the advantages of direct driven, high thrust density, and high efficiency, flux-switching linear motor (FSLM) is required for many applications, including aerospace and automotive. However, the vibration caused by detent force and difficulties in the assembly produced by the large normal force become the barriers that restrict its development. The paper aims to discuss these issues.

In order to improve the electromagnetic performance of double-sided multi-tooth FSLM (DMTFSLM), a yokeless DMTFSLM with moving primary is proposed and compared with normal DMTFSLM. Moreover, with theoretical analysis, the selection principle of slot-pole number combination is obtained. DMTFSLMs with four slot/pole combinations, 6s/16p, 6s/17p, 6s/19p, 6s/20p, are analyzed based on finite element analysis model. Finally, several parameters of this yokeless DMTFSLM have been optimized to obtain the better performance.

In yokeless DMTFSLM, it is found that the asymmetry of Back-EMF caused by the end-effect is eliminated, which leads to a better thrust force performance in comparison with the normal structure. The small attractive force between the secondary and the primary makes it easier for assembly and also can reduce the friction, which is more suitable for high-speed application. In addition, the best slot-pole combination rule is found through a simple theoretical analysis.

The yokeless DMTFSLM has excellent electromagnetic performance, such as high thrust density, negligible normal force, and small force ripple. It is a strong candidate for high-precision device.

With respect to the multiple-attribute decision-making problem with subjective preference for a certain attribute whose weight-value range have been given over other attributes whose weight values are unknown, a method based on the mean value of the grey number is proposed to analyse the decision-making problem. This method is used to choose a supply-chain partner under the condition that the decision makers have a preference for a certain attribute of various alternatives. The paper aims to discuss these issues.

First, the middle value of the preferred attribute’s weight-value range is supposed to be its weight value according to the content of the mean value of the grey number. Second, to reflect the decision maker’s subjective preference information, an improved optimisation model that requests the minimum deviation between the actual and expected numerical value of each attribute is constructed to assess the attributes’ weights. Third, the correlated degree and the correlation matrix, which are determined by the weight values of all attributes, are used to rank all the alternatives.

This paper provides a method for making a decision when decision makers have a preference for a certain attribute from an array of various alternatives, and the range of the certain attribute’s weight value is given but the weight value of the other attributes is unknown. When applied to supply-chain partner selection, this method proves feasible and effective.

This method is feasible and effective when applied to supply-chain partner selection, and can be applied to other kinds of decision-making problems. This means it has significant theoretical importance and extensive practical value.

Based on the mean value of the grey number, an optimisation model is built to determine the importance degree of each attribute, then the correlated degree of each alternative is combined to rank all the alternatives. This method can suit the decision makers’ subjective preference for a certain attribute well.