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A quantitative approach for construction pollution control that is based on construction resource levelling is presented. The parameters of construction pollution index (CPI) and hazard magnitude (hi) are treated as a pseudo resource and integrated with a project’s construction schedule. When the level of pollution for site operations exceeds the permissible limit identified by a regulatory body, a Genetic Algorithm (GA) enhanced levelling technique is used to re‐schedule project activities so that the level of pollution can be re‐distributed and thus reduced. The GA enhanced resource levelling technique is demonstrated using 20 on‐site construction activities in a project. Experimental results indicate that the proposed GA enhanced resource levelling method performs better than the traditional resource levelling method used in MS Project©. The proposed method is an effective tool that can be used by project managers to reduce the level of pollution at a particular period of time; when other control methods fail.

A quantitative approach for managing construction pollution control that is based on construction resource leveling is presented. The parameters of construction pollution index, hazard magnitude are treated as a pseudo resource and integrated with a project’s construction schedule. When the level of pollution for site operations exceeds the permissible limit identified by a regulatory body, a genetic algorithm (GA) enhanced leveling technique is used to re‐schedule project activities so that the level of pollution can be re‐distributed and thus reduced. The GA enhanced resource leveling technique is demonstrated using 20 on‐site construction activities in a project. Experimental results indicate that proposed GA enhanced resource leveling method performs better than the traditional resource leveling method used in MS Project© The proposed method is an effective tool that can be used by project managers to reduce the level of pollution at a particular period of time; when other control methods fail.

The target of this research is to develop a mathematical model which combines the Resource-Constrained Multi-Project Scheduling Problem (RCMPSP) and the Multi-Skilled Resource-Constrained Project Scheduling Problem (MSRCPSP). Due to the importance of resource management, the proposed formulation comprises resource leveling considerations as well. The model aims to simultaneously optimize: (1) the total time to accomplish all projects and (2) the total deviation of resource consumptions from the uniform utilization levels.

The K-Means (KM) and Fuzzy C-Means (FCM) clustering methods have been separately applied to discover the clusters of activities which have the most similar resource demands. The discovered clusters are given to the scheduling process as priori knowledge. Consequently, the execution times of the activities with the most common resource requests will not overlap. The intricacy of the problem led us to incorporate the KM and FCM techniques into a meta-heuristic called the Bi-objective Symbiosis Organisms Search (BSOS) algorithm so that the real-life samples of this problem could be solved. Therefore, two clustering-based algorithms, namely, the BSOS-KM and BSOS-FCM have been developed.

Comparisons between the BSOS-KM, BSOS-FCM and the BSOS method without any clustering approach show that the clustering techniques could enhance the optimization process. Another hybrid clustering-based methodology called the NSGA-II-SPE has been added to the comparisons to evaluate the developed resource leveling framework.

The practical importance of the model and the clustering-based algorithms have been demonstrated in planning several construction projects, where multiple water supply systems are concurrently constructed.

Reviewing the literature revealed that there was a need for a hybrid formulation that embraces the characteristics of the RCMPSP and MSRCPSP with resource leveling considerations. Moreover, the application of clustering algorithms as resource leveling techniques was not studied sufficiently in the literature.

Aim of the present monograph is the economic analysis of the role of MNEs regarding globalisation and digital economy and in parallel there is a reference and examination of some legal aspects concerning MNEs, cyberspace and e‐commerce as the means of expression of the digital economy. The whole effort of the author is focused on the examination of various aspects of MNEs and their impact upon globalisation and vice versa and how and if we are moving towards a global digital economy.

The purpose of this paper is to propose a Non-Linear Integer Programming (NLIP) model that solves the resource leveling problem while reducing the negative effect of the total float loss on risk.

An NLIP model is formulated to solve the resource leveling optimization problem incorporating float loss cost (FLC). The proposed model is implemented using “What’s Best solver” for Excel. The FLC is calculated using the float commodity approach. An example is solved using the proposed model in order to illustrate its applicability. Sensitivity analysis is also performed.

The results confirmed that resource leveling reduces the available float of non-critical activities; decreases schedule flexibility and reduces the probability of project completion. The probability of timely completion dropped from 50 percent (for the normal schedule with 32 resource fluctuations) to 13.5 percent for leveled resources with zero fluctuations. Using the proposed method, the number of resource fluctuations is 8 but the probability of completing the project on time improved to 20 percent.

The proposed model allows project managers to exercise new trade-offs between resource leveling and schedule flexibility which will ultimately improve the chances of successful project delivery.

Resource leveling techniques result in reducing the available total float for the non-critical activities. Existing methods focus on moving noncritical activities within their available float and ignore the impact of the resulting float loss. This reduces the schedule flexibility and increase the risk of project delays. The proposed model incorporates the FLC into the resource leveling optimization problem resulting in more efficient schedules with improved resource utilization while keeping some schedule flexibility.

Environmental volatility is a central construct in strategy studies. This paper argues that three factors confound the literature on volatility: asymmetry in conceptualization, asymmetry in operationalization, and lack of attention to level of analysis. These limitations inhibit the development of the concept and make much of the research on volatility non‐additive. However, environments do matter and to make better sense of it we need a meta‐conceptualization. To do this, the paper presents a process‐based resources‐oriented view of volatility that argues that the volatility experienced by the firm is largely a function of the resources it has available to meet the demands made of it. It is proposed that volatility originates from four basic resource configurations: managerial‐human resources configuration, physical resources‐conversion configuration, intangible resources configuration, and positional configuration. Propositions consistent with prior theories and incorporating the new resources‐oriented viewpoint are presented and discussed.

This paper illuminates the distinction between individual and organizational actors in business-to-business markets as well as the coexistence of formal and informal mechanisms of coordination in multinational corporations. The main questions addressed include the following. (1) What factors influence the occurrence of personal contacts of foreign subsidiary managers in industrial multinational corporations? (2) How such personal contacts enable coordination in industrial markets and within multinational firms? The theoretical context of the paper is based on: (1) the interaction approach to industrial markets, (2) the network approach to industrial markets, and (3) the process approach to multinational management. The unit of analysis is the foreign subsidiary manager as the focal actor of a contact network. The paper is empirically focused on Portuguese sales subsidiaries of Finnish multinational corporations, which are managed by either a parent country national (Finnish), a host country national (Portuguese) or a third country national. The paper suggests eight scenarios of individual dependence and uncertainty, which are determined by individual, organizational, and/or market factors. Such scenarios are, in turn, thought to require personal contacts with specific functions. The paper suggests eight interpersonal roles of foreign subsidiary managers, by which the functions of their personal contacts enable inter-firm coordination in industrial markets. In addition, the paper suggests eight propositions on how the functions of their personal contacts enable centralization, formalization, socialization and horizontal communication in multinational corporations.

Employees today face a number of threats to their work and financial well-being (i.e., economic stress). In an aim to provide an agenda and theoretical framework for research on multilevel outcomes of economic stress, the current chapter considers how employees’ economic stress gives rise to emergent outcomes and how these emergent outcomes feed back to influence well-being. Specifically, we draw from Conservation of Resources theory to integrate competing theoretical perspectives with regard to employees’ behavioral responses to economic stress. As employees’ behaviors influence those with whom they interact, we propose that behavioral responses to economic stress have implications for group-level well-being (e.g., interpersonal climate, cohesion) and group-level economic stress. In turn, group-level and individual-level behavioral outcomes influence well-being and economic stress in a multilevel resource loss cycle. We discuss potential opportunities and challenges associated with testing this model as well as how it could be used to examine higher-level emergent effects (e.g., at the organizational level).

Drawing from research on personal resources (e.g., Baumeister, Bratslavsky, Muraven, & Tice, 1998; Fredrickson, 1998) and the episodic nature of work (Beal, Weiss, Barros, & MacDermid, 2005), we examine research and theory relevant to the study of momentary recovery in the workplace. Specifically, we propose that the nature of within workday breaks influences the levels of psychological resources, which in turn influence various workplace outcomes. First, we discuss the momentary approach to studying workplace breaks and consequent resource levels. In doing so, we distinguish between two types of breaks, respites and chores; and we detail two types of psychological resources, regulatory and affective resources. Consequences of psychological resource levels on emotional exhaustion and performance are considered. We also explore possible moderators of the proposed relationships; we discuss job and individual characteristics, and motivation to perform. Finally, we conclude the chapter with a brief discussion on future research and possible applications of the momentary approach to work recovery in organizations.