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In this paper an outline of the development of methods for the analysis of non‐linear circuits is presented. Non‐inert and inert elements have been discerned and an inertia measure has been proposed. For this purpose, an exponential function with time constant T equal to T_R, T_L, or T_C is formulated for an element of type R, L, or C, respectively. In circuits with the imposed cause, which varies sinusoidally in time with period T_e, the following situations are distinguished and considered: T_e ≫ T; T_e ≪ T; and T_e ≈ T. In the first case, the effect changes in time according to the non‐linear characteristic of the element. In the second case, the respective circuit is referred to as the “quasi‐linear”, because for the sinusoidal cause the effect is also sinusoidal. In the third case, the hysteresis occurs and the effect is a two‐valued function. The hysteresis effect occurs also in resistive elements.

Although there is a small body of empirical research on the working lives of managers, both the popular media and the academic literature tend to ignore the distinct ways that role identities such as age and gender intersect to create a complex work–life interface for diverse managers. This gap is especially surprising considering that managerial roles are defined by unique demands and expectations that likely intersect with the differential life course shifts experienced by men and women, which has the potential to create specific challenges across the work and life domains of managers. The current study aims to address this gap through an intersectional examination of the non-linear effects of age and gender on the work–life balance of managers.

Using a sample of 421 managers, the authors apply statistical tests of the incremental validity of non-linear interaction terms to examine the complex relationship between age, gender and work–life balance.

Results support a non-linear U-shaped main effect of age on leader work–life balance. This effect is moderated by gender, however, with a non-linear U-shaped effect of age on work–life balance being supported for male managers – with female managers displaying no effect of age on work–life balance.

Based on these findings, the authors highlight the need for increased availability of flexible schedules and employee empowerment for managers as well as general employees.

The current study offers one of the first tests of the intersection of age and gender on the work–family interface of managers.

This paper deals with theory and computation of fluid flow in fractured rock. Non‐Darcian flow behavior was observed in pumping tests at the geothermal research site at Soultz‐sous‐Forêts (France). Examples are examined to demonstrate the influence of fracture roughness and pressure‐gradient dependent permeability on pressure build‐up. A number of test examples based on classical models are investigated, which may be suited as benchmarks for non‐linear flow. This is a prelude of application of the non‐linear flow model to real pumping test data. Frequently, conceptual models based on simplified geometric approaches are used. Here, a realistic fracture network model based on borehole data is applied for the numerical simulations. The obtained data fit of the pumping test shows the capability of fracture network models to explain observed hydraulic behavior of fractured rock systems.

The purpose of this paper is to describe the introduction of simple assembly line balancing problems (SALBPs) under four joint combinations of two learning effects and two deterioration effects.

In this paper, effects of learning and deterioration are considered simultaneously. By the effects of learning and deterioration, it is meant that the task time of a task is defined by increasing function of its execution start time and position in the sequence.

It was shown that polynomial solutions can be obtained for SALBP under four joint combinations of two learning effects and two deterioration effects. Furthermore, this paper also discusses the adaptations of the proposed models by using known ALB problem.

In this paper, SALBPs were introduced under four joint combinations of two learning effects and two deterioration effects. Position dependent learning effect and time dependent learning effect were considered for learning effect when linear deterioration effect and non‐linear deterioration effect were taken up.

As a field, we should put more emphasis on interpreting the magnitude of coefficient estimates rather than only assessing statistical significance. To support this claim, I demonstrate how focusing only on statistical significance can lead to incorrect and incomplete conclusions in many common applications of the linear regression model. Moreover, I demonstrate why interpreting coefficient estimates in common non-linear estimators (e.g., probit, logit, Poisson, and negative binomial estimators) requires additional care compared to the linear regression model.

The application of computational plasticity to the very practical engineering problem of crash‐worthiness of vehicle safety cab frames during impact and rollover incidents is described. The resulting behaviour of these structures cannot be determined solely by strict elastic analyses as plastic behaviour is intrinsic to the problem. The importance of predicting the deformations of the cab structure under extreme loadings lies in a consideration for the safety of its occupants. Physical testing is extremely valuable here but is costly and time‐consuming. The role of the computer is thus evident in producing rapid estimates of cab collapse modes, loadings and deformations. Three main causes of non‐linearity are identified in the behaviour of ductile framed structures under static loading, i.e. the effects of plasticity in the structural material, the effects of axial forces and the effects of large displacements of the structure under load. The paper describes and compares two computer programs which have been used to model the behaviour of vehicle cab frames when subjected to roof crush loading in a static test. Both programs employ non‐linear beam finite elements to model the behaviour of a framed structure. One program runs in an iterative fashion while the other runs in an incremental fashion.

This study aims to present an extended service-profit chain (SPC) framework for assessing service performance. This framework is then used to investigate non-linear and asymmetric links between service delivery investments and customer satisfaction, as well as time lags in organisational performance outcomes.

The study draws on panel data with repeated measures from a sample of automotive after sales service departments. Data collected comprises both objective and survey-based data, including operational inputs, productivity, service quality, service experience, behavioural intentions, customer retention and organisational performance.

Non-linear and asymmetric effects are identified, suggesting that customers’ evaluations of service performance are more sensitive to negative performance (dissatisfaction) than positive performance (satisfaction). Accordingly, focusing on attributes for which customers are experiencing negative performance first, and then allocating resources to attributes for which customers are experiencing positive performance, can be far more consequential for improving customer satisfaction.

From a practical perspective, the findings deepen current understanding of the relationships between service performance metrics. They also provide guidance for managers seeking to better deploy service resources to enhance service quality, customer satisfaction and customer retention to improve profitability over time.

Drawing on a unique and rich data set, this study provides a significant improvement on previous SPC frameworks by adding new dimensions identified in recent meta-analyses and addresses calls for more research into non-linear, asymmetric and longitudinal effects within the SPC.

The purpose of this paper is to present a quick inspection method based on the post-flight data to examine static aeroelastic behavior for transport aircraft subjected to instantaneous high g-loads.

In the present study, the numerical approach of static aeroelasticity and two verified cases will be presented. The non-linear unsteady aerodynamic models are established through flight data mining and the fuzzy-logic modeling of artificial intelligence techniques based on post-flight data. The first and second derivatives of flight dynamic and static aeroelastic behaviors, respectively, are then estimated by using these aerodynamic models.

The flight dynamic and static aeroelastic behaviors with instantaneous high g-load for the two transports will be analyzed and make a comparison study. The circumstance of turbulence encounter of the new twin-jet is much serious than that of four-jet transport aircraft, but the characteristic of stability and controllability for the new twin-jet is better than those of the four-jet transport aircraft; the new twin-jet transport is also shown to have very small aeroelastic effects. The static aeroelastic behaviors for the two different types can be assessed by using this method.

As the present study uses the flight data stored in a quick access recorder, an intrusive structural inspection of the post-flight can be avoided. A tentative conclusion is to prove that this method can be adapted to examine the static aeroelastic effects for transport aircraft of different weights, different sizes and different service years in tracking static aeroelastic behavior of existing different types of aircraft. In future research, one can consider to have more issues of other types of aircraft with high composite structure weight.

This method can be used to assist airlines to monitor the variations of flight dynamic and static aeroelastic behaviors as a complementary tool for management to improve aviation safety, operation and operational efficiency.

This paper presents the generalized theory of the most important energy principles in structural analysis. All derive from two basic complementary theorems denoted as the principles of virtual displacements and virtual forces. Both exact and approximate methods are discussed and particular attention is paid to the derivation of upper and lower limits. The theory is not restricted to linearly elastic bodies but includes ab initio the effect of non‐linear stress‐strain laws and thermal strains. Finally the basic principles are illustrated on a number of simple examples in preparation for the more complex ones to appear in Parts II and III.