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Temporary and permanent organisations have contrasting yet co-dependent perspectives regarding time; temporary organisations are made to ‘die’, yet most of them exist to enable permanent organisations to ‘survive’. The authors studied the temporal tensions of strategic initiatives – that is, temporary organisations that aim to implement strategic change in permanent organisations. Our empirical data identified three temporal tensions emerging when senior managers timed their strategic initiatives: ambition versus realism when enacting the time horizon, patience versus urgency when enacting the pace, and clock time versus event time when enacting the temporal perspective. By evoking the literature on paradox and temporal work, the authors extend the view of temporality at the temporary and permanent interface and indicate how temporal work played an important role in creating, reinforcing, or transforming temporal tensions. The authors conclude by providing implications for theory and practice.

The campaign for striker replacement legislation, which began in the late 1980s and had effectively ended by the mid-1990s, was the most important political battle over labor legislation since the defeat of the Labor Law Reform Bill in 1978. Striker replacement was the AFL-CIO’s top legislative priority in the early 1990s and, coming quickly after the passage of NAFTA, which labor had opposed, the defeat of its campaign solidified organized labor’s reputation for failure in legislative battles. As yet, however, the political campaign for striker replacement legislation has attracted surprisingly little attention from industrial relations scholars.

Using Spanish establishment-level data on temporary and permanent job and worker flows, we examine firms’ relative usage of fixed-term contracts in response to changes in their prior net employment expectations for the short-run and the long-run – viewed as proxies of how a wide variety of future shocks are ultimately perceived by establishments. The employment response of establishments to changing net employment expectations for the short-run is, primarily, suggestive of their reliance on fixed-term contracts as a buffer to cushion short-run changes in demand as well as to shield permanent workers from downward workforce adjustments. In contrast, their response to changes in net employment expectations for the long-run mostly hints on the use of fixed-term contracts as a screening device. Therefore, policies providing financial incentives to convert fixed-term into permanent contracts – thus targeting firms’ using fixed-term contracts as a screening device, are likely to only have limited effectiveness.

Permanent magnet synchronous spherical motors can have wide use in robotics and industrial automation. They enable three-DOF omnidirectional motion of their rotor. They are suitable for several applications, such as actuation in robotics, traction in electric vehicles and use in several automation systems. Unlike conventional synchronous motors, permanent magnet synchronous spherical motors consist of a fixed inner shell, which is the stator, and a rotating outer shell, which is the rotor. Their dynamic model is multivariable and strongly nonlinear. The treatment of the associated control problem is important.

In this paper, the multivariable dynamic model of permanent magnet synchronous spherical motors is analysed, and a nonlinear optimal (H-infinity) control method is developed for it. Differential flatness properties are proven for the spherical motors’ state-space model. Next, the motors’ state-space description undergoes approximate linearization with the use of first-order Taylor series expansion and through the computation of the associated Jacobian matrices. The linearization process takes place at each sampling instance around a time-varying operating point, which is defined by the present value of the motors’ state vector and by the last sampled value of the control input vector. For the approximately linearized model of the permanent magnet synchronous spherical motors, a stabilizing H-infinity feedback controller is designed. To compute the controller’s gains, an algebraic Riccati equation has to be repetitively solved at each time-step of the control algorithm. The global stability properties of the control scheme are proven through Lyapunov analysis. Finally, the performance of the nonlinear optimal control method is compared against a flatness-based control approach implemented in successive loops.

Due to the nonlinear and multivariable structure of the state-space model of spherical motors, the solution of the associated nonlinear control problem is a nontrivial task. In this paper, a novel nonlinear optimal (H-infinity) control approach is proposed for the dynamic model of permanent magnet synchronous spherical motors. The method is based on approximate linearization of the motor’s state-space model with the use of first-order Taylor series expansion and the computation of the associated Jacobian matrices. Furthermore, the paper has introduced a different solution to the nonlinear control problem of the permanent magnet synchronous spherical motor, which is based on flatness-based control implemented in successive loops.

The presented control approaches do not exhibit any limitations, but on the contrary, they have specific advantages. In comparison to global linearization-based control schemes (such as Lie-algebra-based control), they do not make use of complicated changes of state variables (diffeomorphisms) and transformations of the system's state-space description. The computed control inputs are applied directly to the initial nonlinear state-space model of the permanent magnet spherical motor without the intervention of inverse transformations and thus without coming against the risk of singularities.

The motion control problem of spherical motors is nontrivial because of the complicated nonlinear and multivariable dynamics of these electric machines. So far, there have been several attempts to apply nonlinear feedback control to permanent magnet-synchronous spherical motors. However, due to the model’s complexity, few results exist about the associated nonlinear optimal control problem. The proposed nonlinear control methods for permanent magnet synchronous spherical motors make more efficient, precise and reliable the use of such motors in robotics, electric traction and several automation systems.

The treated research topic is central for robotic and industrial automation. Permanent magnet synchronous spherical motors are suitable for several applications, such as actuation in robotics, traction in electric vehicles and use in several automation systems. The solution of the control problem for the nonlinear dynamic model of permanent magnet synchronous spherical motors has many industrial applications and therefore contributes to economic growth and development.

The proposed nonlinear optimal control method is novel compared to past attempts to solve the optimal control problem for nonlinear dynamical systems. Unlike past approaches, in the new nonlinear optimal control method, linearization is performed around a temporary operating point, which is defined by the present value of the system's state vector and by the last sampled value of the control inputs vector and not at points that belong to the desirable trajectory (setpoints). Besides, the Riccati equation which is used for computing the feedback gains of the controller is new, and so is the global stability proof for this control method. Compared to nonlinear model predictive control, which is a popular approach for treating the optimal control problem in industry, the new nonlinear optimal (H-infinity) control scheme is of proven global stability, and the convergence of its iterative search for the optimum does not depend on initial conditions and trials with multiple sets of controller parameters. It is also noteworthy that the nonlinear optimal control method is applicable to a wider class of dynamical systems than approaches based on the solution of state dependent Riccati equations (SDRE). The SDRE approaches can be applied only to dynamical systems which can be transformed into the linear parameter varying form. Besides, the nonlinear optimal control method performs better than nonlinear optimal control schemes, which use approximation of the solution of the Hamilton–Jacobi–Bellman equation by Galerkin series expansions. Furthermore, the second control method proposed in this paper, which is flatness-based control in successive loops, is also novel and demonstrates substantial contribution to nonlinear control for robotics and industrial automation.

The unemployment rate (UR) is the leading macroeconomic indicator used in the credit card loss forecasting. COVID-19 pandemic has caused an unprecedented level of volatility in the labor market variables, leading to new challenges to use UR in the credit risk modeling framework. This paper examines the dynamic relationship between the credit card charge-off rate and the unemployment rate over time.

This study uses quarterly observations of charge-off rates on credit card loans of all commercial banks from Q1 1990 to Q4 2020. Univariate, multivariable, machine learning, and regime-switching time series modeling are employed in this research.

The authors decompose UR into two components – temporary and permanent UR. The authors find the spike in UR during COVID-19 is mainly attributed to the surge in temporary layoffs. More importantly, the authors find that the credit card charge-off rate is primarily driven by permanent UR while temporary UR has little predictive power. During recessions, permanent UR seems to be a stronger indicator than total UR. This research highlights the importance of using permanent UR for credit risk modeling.

The findings in the research can be applied to the credit card loss forecasting and CECL reserve models. In addition, this research also has implications for banks, macroeconomic data vendors, regulators, and policymakers.

The main purpose of this paper is to identify sources of temp agency work satisfaction and discuss whether or not these sources differ from those well‐known to traditional satisfaction research (i.e. those appropriate for employees with a permanent contract).

The paper is a qualitative study (semi‐structured interviews and fieldwork) among low and medium skilled metalworkers (welders and fitters) in two Dutch companies. The authors were able to identify sources for temp agency work satisfaction: organizational conditions, central personality constructs, labour market experiences, and layoff experiences.

The findings in the paper conclude that satisfaction theory is transferable to temp agency workers, but that future satisfaction research should include less studied factors such as labour market and layoff experiences, as well.

The paper is a qualitative case study research within two Dutch companies and involved a certain occupational group: metalworkers. Consequently, the external transferability of the results (i.e. country, occupational group, industries) may be limited. Furthermore, the research approach used does not allow for the making of casual assumptions. For example, it was not possible to address the question as to whether “perceived alternatives” influences “sensation seeking” or vice versa. Longitudinal questionnaire research could help to clarify such issues. Job satisfaction theory in general is helpful in creating a framework for agency work satisfaction when it comes to Human Resource Management policies and practices. However, in order to explain agency workers' satisfaction, there is a need to broaden the traditional psychologically‐orientated theories and include aspects related to history and (occupational) sociology such as work experience in sectors where non‐permanent employment relationships are common.

The paper shows that hiring‐in companies can contribute to agency workers' satisfaction and, it is believed, other non‐permanent workers such as freelancers and collegial loan‐in, by means of equal treatment policies and practices with respect to job characteristics, development and mobility policies, working conditions, direct employee influence, and (fringe‐) benefits.

In this paper the focus has been on a relatively seldom‐discussed phenomenon in employee attitude research: temp agency work satisfaction. The authors focus on sources that can explain the preference for a ménage à trois employment relationship over life‐time employment arrangements with one employer, i.e. a traditional permanent labour contract between two parties.

Looks at how the rise in the use of non‐permanent employees has stimulated much debate concerning the long‐term impact on the success of organizations and skill development at the organizational and national level. Draws on internationally comparable data from 12 countries to explore the relationship between non‐permanent work and organizational profitability, workforce expansion and investment in employee training and development. Argues that national contextual conditions, in terms of employment legislation and training traditions, and the management of non‐permanent workers are important factors affecting the efficiency outcomes associated with using this particular flexible employment option.

The purpose of this paper is to explore the interdependencies between temporary and permanent aspects of project organizing and how they affect the management of public infrastructure operation and maintenance (O&M) activities.

The paper applies a case study approach and uses Lundin and Söderholm's (1995) framework of the temporary organization (with the themes of time, task, team and transition) to distinguish between temporary and permanent aspects of organizing two infrastructure O&M projects.

This paper adds to the literature on temporary organizations by recognizing a mixture of temporary and permanent aspects of project organizing in an empirical project-level example. In line with previous research, the themes of time, task, team and transition were shown to be interdependent. Furthermore, the paper broadens the theory of temporary organizations by presenting a project organization with significant permanent aspects.

Project managers of public sector projects need to be aware of the possible mixture of temporary and permanent aspects of project organizing. Management of projects that are found to have a mixture of temporary and permanent aspects should combine the perspectives and management practices of both temporary and permanent organizing. Not acknowledging permanent aspects could lead to management that is not adapted to the prerequisites of project organizing in this context.

The findings further develop the literature on temporary organizations by recognizing that there is not only a mixture of temporary and permanent aspects between the temporary organization and its permanent environment but there is also a mixture of temporary and permanent aspects of organizing within project organizations.

The purpose of this paper is to compare responses of house prices in three important markets when faced with permanent and temporary shocks to income. It additionally decomposes each historical house price series into its permanent, temporary and deterministic components.

Using quarterly data over 1973‐2008, two‐variable systems of house prices and income are specified for three major house‐owning economies: New Zealand (NZ), the United Kingdom (UK) and the United States of America (USA).

NZ and UK housing markets are sensitive to both permanent and temporary shocks to income, while the US market reacts to temporary shocks with the permanent component having a largely insignificant role to play in house price composition. In NZ, the temporary component of house prices has tended to be positive over time, pushing prices higher than they would have been otherwise; while in the UK, both permanent and temporary components have tended to reinforce each other.

The paper uses state‐of‐the‐art methods to analyse the relationships between income and house prices in three economies.

Taking a 2,000 r/min 10 kW permanent magnet motor as an example, the purpose of this paper is to study the influence of driving modes on the performance of permanent magnet motor at limit conditions, and researched the variation mechanism of motor performance influenced by different driving modes.

A two-dimensional electromagnetic field model of the permanent magnet motor was established, and a rectangular-wave driving circuit was built. By using the finite element method, the electromagnetic field, current, harmonic content and eddy current loss were calculated when the motor operated at rated load and limit load. On the basis of the motor loss calculation, the temperature field of the motor operating at rated condition and limit condition was researched, and the factors that influence motor limit overload capacity were analyzed. By analyzing the motor loss variation at different load conditions, the change mechanism of the motor temperature field was determined further. Combined with the related experiments, the correctness of the above analysis was verified.

Permanent magnet synchronous motor (PMSM) driven by sine wave is better compared with brushless direct current motor (BLDCM) driven by rectangular wave in reducing the magnetic field harmonics, motor losses and optimizing the temperature distribution in the motor. The method driven by sine wave could improve the motor output performance including the motor efficiency and the motor overload capacity. The winding temperature is the most important factor that limits the output capability of PMSM operating for a long time. However, because of the large rotor eddy current losses, the permanent magnet temperature is the most important factor that limits the output capability of BLDCM operating for a long time.

The influence of driving modes on the motor magnetic field, losses and temperature distribution, efficiency and overload capacity was determined, and the influence mechanism was also analyzed. Combined with the analysis of the electromagnetic and temperature fields, the advantages of different driving modes were presented. This study could provide an important basis for the design of permanent magnet motors with different driving modes, and it also provides reference for the application of permanent magnet motor.

This paper presents the influence of driving modes on permanent magnet motors. The limit output capacity of the motor with different driving modes was studied, and the key factors limiting the motor output capability were obtained.