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Assembly is the last step in manufacturing processes. The two-sided assembly line balancing problem (TALBP) is a typical research focus in the field of combinatorial optimization. This paper aims to study a multi-constraint TALBP-I (MC-TALBP-I) that involves positional constraints, zoning constraints and synchronism constraints to make TALBP more in line with real production. For enhancing quality of assembly solution, an improved imperialist competitive algorithm (ICA) is designed for solving the problem.

A mathematical model for minimizing the weighted sum of the number of mated-stations and stations is established. An improved ICA is designed based on a priority value encoding structure for solving MC-TALBP-I.

The proposed ICA was tested by several benchmarks involving positional constraints, zoning constraints and synchronism constraints. This algorithm was compared with the late acceptance hill-climbing (LAHC) algorithm in several instances. The results demonstrated that the ICA provides much better performance than the LAHC algorithm.

The best solution obtained by solving MC-TALBP-I is more feasible for determining the real assembly solution than the best solution obtained by solving based TALBP-I only.

A novel ICA based on priority value encoding is proposed in this paper. Initial countries are generated by a heuristic method. An imperialist development strategy is designed to improve the qualities of countries. The effectiveness of the ICA is indicated through a set of benchmarks.

Resource-constrained assembly lines are widely found in industries that manufacture complex products. In such lines, tasks may require specific resources to be processed. Therefore, decisions on which tasks and resources will be assigned to each station must be made. When the number of available stations is fixed, the problem’s main goal becomes the minimisation of cycle time (type-II version). This paper aims to explore this variant of the problem that lacks investigation in the literature.

In this paper, the authors propose mixed-integer linear programming (MILP) models to minimise cycle time in resource-constrained assembly lines, given a limited number of stations and resources. Dedicated and alternative resource types for tasks are considered in different scenarios.

Besides, past modelling decisions and assumptions are questioned. The authors discuss how they were leading to suboptimal solutions and offer a rectification.

The proposed models and data set fulfil more practical concerns by taking into account characteristics found in real-world assembly lines.

The proposed MILP models are applied to an existing data set, results are compared against a constraint programming model, and new optimal solutions are obtained. Moreover, a data set extension is proposed due to the simplicity of the current one and instances up to 70 tasks are optimally solved.

Literature reveals that citizens’ intentions or willingness to adopt and use e-government services in developing countries like Ghana have not been encouraging regardless of the importance of these services. This study aims to examine the factors that inhibit the virtualization of government to citizen e-government processes by assessing citizens’ intentions to resist or use government’s virtualized processes.

This study used a survey questionnaire to collect data from public school teachers who are users of the Government of Ghana’s e-pay slip system. Out of 500 questionnaires administered, only 423 useable responses were obtained. The data was analyzed with both inferential and descriptive statistics.

The results of this study showed that process virtualizability significantly predicts virtual process use, and it is associated with user resistance toward virtual process use.

The findings will help governments and managers to comprehend that certain processes are more acquiescent to virtualization than others.

This paper provides researchers with a contemporary perspective toward understanding the adoption and use of e-government services in sub-Saharan Africa through the lens of process virtualization theory.

This study investigated the impact of the virtualization requirements of the learning process on students' satisfaction and their intention to continue using online learning.

A research model was developed using the process virtualization theory (PVT); it was validated empirically using data obtained from an online questionnaire-based survey of 489 undergraduate students.

The main results support the role of representation for sensory requirements, sensory requirements, reach, representation for relationship requirements and relationship requirements on shaping students' satisfaction, which all also have a significant influence on students' intention to continue using online learning. Relevance factors are responsible for 61.6% of the variance in students' satisfaction and 83.6% of the variance in their intention to continue using online learning. However, neither the synchronism requirements nor the identification and control requirements had a significant effect on students' satisfaction or on their intention to continue using online learning.

The present research focused on PVT in an online learning context; consequently, a new set of factors that influenced students' satisfaction with and intentions to continue using online learning was empirically tested for the first time. This research contributes to the literature on information systems because it advances the generalizability and applicability of the PVT in a new context and new cultural setting. Moreover, the research apprises researchers and practitioners of new factors, which should be understood and fulfilled to make virtual learning equivalent to the face-to-face learning experience.

This chapter investigates the relative magnitude of the benefits of global diversification from the viewpoint of domestic investors in various countries by forming time-rolling efficient frontiers. To enhance feasibility of asset allocation strategies, the constraints of short-sales and over-weighting investments are taken into account. The empirical results suggest that local investors in less developed countries, particularly in Latin America, East Asia, and Southern Europe, comparatively benefit more from global diversification. Investors in the countries of civic-law origin tend to benefit more from global investment than the ones in the common-law states. Although the global market has become more integrated over the past decades, diversification benefits for domestic investors declined but did not vanish. The results of this chapter are useful for asset management professionals to determine target markets to promote the sales of international funds.

In this work, a method to design a slotless permanent magnet machine (SPMM) based on the joint use of an analytical model and deterministic global optimization algorithms is addressed. The purpose of this study is to propose to include torque ripples as an extra constraint in the optimization phase involving de facto the study of a semi-infinite optimization problem.

Based on the use of a well-known analytical model describing the electromagnetic behavior of an SPMM, this analytical model has been supplemented by the calculus of the dynamic torque and its ripples to carry out a more accurate optimized sizing method of such an electromechanical converter. As a consequence, the calculated torque depends on a continuous variable, namely, the rotor angular position, resulting in the definition of a semi-infinite optimization problem. The way to solve this kind of semi-infinite problem by discretizing the rotor angular position by using a deterministic global optimization solver, that is to say COUENNE, via the AMPL modeling language is addressed.

In this study, the proposed approach is validated on some numerical tests based on the minimization of the magnet volume. Efficient global optimal solutions with torque ripples about 5% (instead of 30%) can be so obtained.

The analytical model does not use results from the solution of two-dimensional field equations. A strong assumption is put forward to approximate the distribution of the magnetic flux density in the air gap of the SPMM.

The problem to design an SPMM can be efficiently formulated as a semi-infinite global optimization problem. This kind of optimization problems are hard to solve because they involve an infinity of constraints (coming from a constraint on the torque ripple). The authors show in this paper that by using analytical models, a discretization method and a deterministic global optimization code COUENNE, this problem is efficiently tackled. Some numerical results show that the deterministic global solution of the design can be reached even if the step of discretization is small.

NO component of the modern aero and automobile engine has been more uncertain in action and more troublesome in service than the valve spring.

Permanent magnet (PM) brushless machines equipped with fractional‐slot concentrated‐windings (FSCW) have been receiving considerable attention over the past few years, due to the fact that they have short end‐windings, a high‐slot fill factor, a high efficiency and power density, and good flux‐weakening and fault‐tolerance capabilities. A key design parameter for such machines is the phase winding inductance since this has a significant impact on the performance, as well as on the magnitude of any reluctance torque. The purpose of this paper is to describe a detailed investigation of the various components of the winding inductance in machines equipped with both overlapping and non‐overlapping windings and different slot/pole number combinations. It also examines the influence of key design parameters, which affect the inductance components, with particular reference to the inductances of machines in which all the teeth are wound and those in which only alternate teeth are wound.

The paper analyzes and compares various inductance components which result from different winding configurations.

It is shown that the main component of the winding inductance is the relatively large slot‐leakage component. Both analytical and finite element models are employed and predicted results are validated on several prototype machines.

Such a thorough investigation of the various inductance components for these type of machines has not been presented before. The paper will serve as a good reference for engineers and researchers designing PM machines equipped with FECW.

The purpose of this paper is to present an approach to incorporating mobility into continuous manufacturing following the advent of Industry 4.0 (I4.0).

The investigation is based on a year-long canonical action research into a paper-manufacturing company implementing core I4.0 technologies.

The findings show how to: classify manufacturing mobility strategy based on the dimensions of team, task and control; design business processes enabled by mobile cyber–physical resources; involve different stakeholders in modeling mobility; and create a comprehensive guide to assist in implementing the mobile digitalization required by I4.0.

Despite the complexity, richness and depth of the insights obtained in this research for mobility management in process industries, this inquiry was conducted in a single organization.

As the fourth industrial revolution encourages decentralization and increased interaction between humans and machines, this paper presents a model to capture the mobility potential in manufacturing. The tools proposed in this research can be used to steer investments in industry transformations that fuse the physical and digital worlds, overcoming mobility constraints.

Theoretically, this paper expands the concept of manufacturing mobility in I4.0. In practice, it proposes a participative roadmap to assist technology management in increasingly decentralized environments, identifying the intertwined network of cyber–physical actors, processes and services.

States that today, the corporate environment is characterized by complexity, uncertainty, contingency and evolution. In these conditions, the design of a learning organization should be based upon Einstein’s conception of time, which represents a dramatic shift from our traditional organizations built upon Newton’s time. In this research, the author defined nine temporal dimensions of organizational culture (for instance schedules and deadlines) which could be managed in order to facilitate change and learning and examined them in relation to individuals’ polychronic behavior, a temporal orientation. Polychronic people do many things at once and experience time as a relatively intangible phenomenon that emerges from specific events. This empirical investigation shows that polychronic time use is related to several dimensions of temporal culture. These results can be used to make the development of learning organizations more effective, particularly when applied to human resource activities and programs.