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The manufacture of flexi‐rigid multilayer boards poses a number of problems which are not met with in ordinary multilayer production or in the making of plain flexible circuits. Steps have to be taken to overcome the poor dimensional stability of thin polyimide foils during processing and to ensure that those portions of the assembly which need to be rigid are bonded whilst flexible portions are left unbonded other than for a cover coat. Pressure on cover coated flexible areas must be maintained during bonding without allowing resin to now over these areas, and finally the bonded unit must be profiled, often with superimposed flexible areas of different shapes. This article describes some of the techniques used by a leading manufacturer to overcome these problems. Several of the processes described are covered by patents held by Exacta Circuits Ltd. This article is an extract from a forthcoming book ‘Handbook of Multilayer Printed Circuits’ to be published at the end of the year by Electrochemical Publications Ltd., 8 Barns Street, Ayr, Scotland.

Flexible circuitry and flexible interconnects are high technology products that require a good understanding of flexible laminates and their properties to ensure the proper design of a functional part. Many designers use flexible interconnects for packaging and multiplane interconnections, but incorrectly compare flexible materials to rigid laminates. Flexible materials and design considerations when using flexible materials are reviewed, with a brief overview of the combination of flex and rigid materials in a flex/rigid multilayer circuit.

Under the high-speed operating conditions, the effects of wheelset elastic deformation on the wheel rail dynamic forces will become more notable compared to the low-speed condition. In order to meet different analysis requirements and selecting appropriate models to analyzing the wheel rail interaction, it is crucial to understand the influence of wheelset flexibility on the wheel-rail dynamics under different speeds and track excitations condition.

The wheel rail contact points solving method and vehicle dynamics equations considering wheelset flexibility in the trajectory body coordinate system were investigated in this paper. As for the wheel-rail contact forces, which is a particular force element in vehicle multibody system, a method for calculating the Jacobian matrix of the wheel-rail contact force is proposed to better couple the wheel-rail contact force calculation with the vehicle dynamics response calculation. Based on the flexible wheelset modeling approach in this paper, two vehicle dynamic models considering the wheelset as both elastic and rigid bodies are established, two kinds of track excitations, namely normal measured track irregularities and short-wave irregularities are used, wheel-rail geometric contact characteristic and wheel-rail contact forces in both time and frequency domains are compared with the two models in order to study the influence of flexible wheelset rotation effect on wheel rail contact force.

Under normal track irregularity excitations, the amplitudes of vertical, longitudinal and lateral forces computed by the flexible wheelset model are smaller than those of the rigid wheelset model, and the virtual penetration and equivalent contact patch are also slightly smaller. For the flexible wheelset model, the wheel rail longitudinal and lateral creepages will also decrease. The higher the vehicle speed, the larger the differences in wheel-rail forces computed by the flexible and rigid wheelset model. Under track short-wave irregularity excitations, the vertical force amplitude computed by the flexible wheelset is also smaller than that of the rigid wheelset. However, unlike the excitation case of measured track irregularity, under short-wave excitations, for the speed within the range of 200 to 350 km/h, the difference in the amplitude of the vertical force between the flexible and rigid wheelset models gradually decreases as the speed increase. This is partly due to the contribution of wheelset’s elastic vibration under short-wave excitations. For low-frequency wheel-rail force analysis problems at speeds of 350 km/h and above, as well as high-frequency wheel-rail interaction analysis problems under various speed conditions, the flexible wheelset model will give results agrees better with the reality.

This study provides reference for the modeling method of the flexible wheelset and the coupling method of wheel-rail contact force to the vehicle multibody dynamics system. Furthermore, by comparative research, the influence of wheelset flexibility and rotation on wheel-rail dynamic behavior are obtained, which is useful to the application scope of rigid and flexible wheelset models.

The purpose of this empirical research was to investigate the individual effects of three dimensions of flexible human resource management (HRM) practices – skill flexibility, behavioral flexibility and human practice flexibility on firm performance and to what extent these relationships are strengthened/weakened when there was the moderation of empowering leadership in small- and medium-sized enterprises (SMEs) of the Kingdom of Bahrain.

The data were collected from chief executive officers (CEOs) through a questionnaire survey method to test the hypothesized relationships. A final dataset of 315 valid responses was utilized for data analysis, and results were analyzed using the Smart partial least squares structural equation modeling (PLS-SEM) technique.

The findings revealed positive effects of skill flexibility, behavioral flexibility and human practice flexibility on firm performance. The moderating role of empowering leadership further strengthened the effects of employee skill flexibility and employee behavioral flexibility had on firm performance. However, empowering leadership did not pose any moderating effect on human practice flexibility and firm performance relationship.

This paper offers implications for theories on HRM and leadership. It also provides valuable insights for organizations and leaders seeking to boost firm performance across SMEs.

This paper offers implications for theories on HRM and leadership and also contributes in the understanding of the modern managers.

This paper investigated the effects of flexible HRM practices on firm performance and the role of empowering leadership across SMEs in Bahrain. It also explored how the performance of SMEs can be improved using flexible HRM practices followed by the presence of empowering leadership.

The purpose of this study is to estimate inputs (outputs) and flexible measures when outputs (inputs) are changed provided that the relative efficiency values remain without change.

A novel inverse data envelopment analysis (DEA) approach with flexible measures is proposed in this research to assess inputs (outputs) and flexible measures when outputs (inputs) are perturbed on condition that the relative efficiency scores remain unchanged. Furthermore, flexible inverse DEA approaches proposed in this study are used for a numerical example from the literature and an application of Iranian banking industry to clarify and validate them.

The findings show that including flexible measures into the investigation effects on the changes of performance measures estimated and leads to more reasonable achievements.

The traditional inverse DEA models usually investigate the changes of some determinate input-output factors for the changes of other given input-output indicators assuming that the efficiency values are preserved. However, there are situations that the changes of performance measures should be tackled while some measures, called flexible measures, can play either input or output roles. Accordingly, inverse DEA optimization models with flexible measures are rendered in this paper to address these issues.

With the rapid development of the 3C industry, the problem of automated operation of 3C wire is becoming increasingly prominent. However, the 3C wire has high flexibility, and its deformation is difficult to model and control. How to realize the automation operation of flexible wire in 3C products is still an important issue that restricts the development of the 3C industry. Therefore, this paper designs a system that aims to improve the automation level of the 3C industry.

This paper designed a visual servo control system. Based on the perception of the flexible wire, a Jacobi matrix is used to relate the deformation of the wire to the action of the robot end; by building and optimizing the Jacobi matrix, the robot can control the flexible wire.

By using the visual servo control system, the shape and deformation of the flexible wire are perceived, and based on this, the robot can control the deformation of the flexible wire well. The experimental environment was built to evaluate the accuracy and stability of the system for controlling the deformation of the flexible wire.

An image-based visual servo system is proposed to operate the flexible wire, including the vision system, visual controller and joint velocity controller. It is a scheme suitable for flexible wire operation, which has helped to automate flexible wire-related industries. Its core is to correlate the motion of the robot end with the deformation of the flexible wire through the Jacobian matrix.

The purpose of this paper is to introduce flexible dye-sensitized solar cells (FDSSCs).

In the third generation solar cells, glass was used as a substrate, which due to its high weight and fragility, was not possible to produce continuously. However, in flexible solar cells, flexible substrates are used as new technology. The most important thing may choose a suitable substrate to produce a photovoltaic (PV) device with optimal efficiency.

Conductive plastics or metallic foils are the two main candidates for glass replacement, each with its advantages and disadvantages. As some high-temperature methods are used to prepare solar cells, metal substrates can be used to prepare PV devices without any problems. In contrast to the advantage of high thermal resistance in metals, metal substrates are dark and do not transmit enough light. In other words, metal substrates have a high loss of photon energy. Like all technologies, PV devices with polymer substrates have technical disadvantages.

In this study, the development of FDSSCs offers improved photovoltaic properties.

The most important challenge is the poor thermal stability of polymers compared to glass and metal, which requires special methods to prepare polymer solar cells. The second important point is choosing the suitable components and materials for this purpose.

Dependence of efficiency and performance of the device on the angle of sunlight, high-cost preparation devices components, limitations of functional materials such as organic-mineral sensitizers, lack of close connection between practical achievements and theoretical results and complicated fabrication process and high weight.

Using Pakistan's public sector higher education institutions as the study site, this study aims to empirically substantiate, under the theoretical underpinnings of job enrichment theory (Hackman and Oldham, 1976) and Maslow's (1943) theory of the hierarchy of needs, the impact of flexible work practices (FWPs), on employee work engagement and organizational attractiveness, with the mediating lens of work life enrichment.

Field data were collected at five higher education institutions located in the Islamabad Capital Territory (ICT) of Pakistan, using the convenience sampling technique and analyzed under the quantitative research paradigm.

This study substantiates with an empirical evidence that flexible work practices (FWPs) have a significant positive impact on both employee work engagement and organizational attractiveness. Markedly, the study findings reveal that the said impact is significantly stronger than that of sabbaticals. Furthermore, the study reveals that the positive relationship is mediated by work life enrichment, signaling its significance in understanding FWP's such impact on employee work engagement and organizational attractiveness.

The study findings provide significant implications for academia, practitioners, and policymakers, in evidence-based recommendations for higher education institutions to design and implement FWPs that are effective in enhancing employee work engagement and organizational attractiveness, and, in turn, leading to improved organizational performance.

This research study provides a novel contribution to the existing literature by exploring the combined impact of flexible work practices on employee work engagement and organizational attractiveness in the peculiar context of Pakistan's public sector higher education institutions. Additionally, the study's focus on the mediating role of work life enrichment further adds to its novelty.

Flexible staffing arrangements have become a permanent feature of employment in many industrial societies. This article examines how employers perceive the consequences of using flexible staffing arrangements. It presents and assesses theoretically informed hypotheses on organisational situations in which negative consequences are more likely to be perceived.

This study uses data (n = 761) from a bespoke employers survey, fielded in the Netherlands in 2019. Structural equation modelling (SEM) is used to measure and explain employers' perception of downsides to flexible staffing arrangements.

Employers report distinct downsides to the use of flexible staffing arrangements in terms of performance, management and employee well-being. Model estimates show that employers using flexible staffing arrangements to acquire specific expertise or to follow other organisations in their sector perceive more downsides.

Empirical research on employers' perception of the disadvantageous consequences of using flexible staffing arrangements is scarce. This article highlights that this practice can discourage investments in human capital and lead to a sense of insecurity among young workers. It draws attention to the relevance of distinguishing between strategic motives when trying to understand organisational behaviour regarding non-standard forms of employment.

This paper aims to provide a comprehensive overview of the challenges and employee development strategies for executives and managers when managing flexible work systems.

The paper takes an employee development perspective to discuss management strategies of flexible work systems. Research findings on the effects of work flexibility through flexible work systems, the challenges and the development strategies that executives and managers can use were reviewed from multi-level perspectives.

The flexible work system is the new normal in the workplace. Lack of social and face-to-face interactions reduces employees’ social learning, jeopardizing managerial justice and weakening the culture. To remain competitive and retain talented employees, executives should reexamine their current employee development strategies and implement new strategies that fit the characteristics of flexible work systems.

To the best of the authors’ knowledge, this is the first comprehensive review of employee development strategies for flexible working arrangements. The paper provides practical guidelines and insights for executives and leaders managing employees under various flexible work systems.