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A scheduling method for determining the critical path in linear projects is presented, that takes into account maximum time and distance constraints in addition to the commonly used minimum time and distance constraints. The maximum constraints, though often present in the specifications of a project, are not considered during the planning procedure, since no method existed to enable scheduling with them. The proposed method builds on the concept of the maximum constraints and expands on the necessary background for their implementation into the schedule. The introduced critical path algorithm allows for grouping linear activities into four categories regarding their critical status and their ability to influence project duration. The method is applied to a low‐pressure pipeline construction project and the results are presented.

The popularity of adventure activities in leisure and tourism is escalating, yet little is known about how personality and perceived constraints can prevent consumption of such activities. The aim of this study was to test a model of the mediating role of psychological constraints in explaining the relationship between personality and interest in adventure activity participation. Based on a questionnaire survey of 1,324 respondents, a quantitative analysis using structural equation modeling (SEM) was carried out. The results show that personality does influence psychological constraints, which in turn have a significant negative effect on adventure activity participation. Increased knowledge about the constraints to adventure activity participation can contribute to realizing the full development potential that lies in adventure consumption in leisure and tourism. Implications of the research can prove valuable in both leisure and tourism marketing and management.

This paper is designed to examine how pleasure travelers manage their travel constraints.

The leisure activity participation constraint negotiation process framework is presented based on previous studies, and the pleasure travel constraint management process models are suggested based on the research survey and interviews.

The pleasure travel constraint management process model was suggested as a result of the survey, and the leisure activity participation constraint management model based on the interviews. These models demonstrate how the process of motivation, constraint, influence factors, and desire flows to result in no participation, or participation of pleasure traveling or other leisure activities.

It is the first trial to construct the pleasure travel and leisure activity participation constraint management models.

The purpose of this paper is to examine the constraints to attend salsa events and festivals across salsa dancing specialization segments.

In‐depth interviews with salsa dancers from three salsa specialization levels were carried out.

Specialization level acted as a predictor of salsa event attendance and there appears to be an event career associated to progress in salsa dancing specialisation, which eventually branched out to a tourist career. Moreover, there was a relationship between the types of constraints and recreation specialisation level, with participants negotiating constraints frequently in order to ensure event attendance.

The interviews were carried out on participants in a mid‐size town in southern England, where the range of competing leisure activities is limited. In addition, the study focused on one recreational activity and one type of event.

Several implications for the marketing of events and festivals can be drawn. First, marketers of salsa events should tie closely with providers of salsa classes and marketers of salsa classes need to provide opportunities for salsa dancers to attend events. Second, marketing strategies aiming at helping recreationists overcome constraints should be different according to the level of specialization. Third, given the nature of constraints faced by the less experienced recreationists, efforts to attract individuals earlier in the specialization path may be fruitless.

This paper is one of the first to explicitly examine the relationship between specialization and constraints to perform behaviors associated to a recreational activity.

Repetitive projects play an important role in the construction industry. A crucial point in scheduling this type of project lies in enabling timely movement of crews from unit to unit so as to minimize the adverse effect of work interruptions on both time and cost. This paper aims to examine a repetitive scheduling problem with work continuity constraints, involving a tradeoff among project duration, work interruptions and total project cost (TPC). To enhance flexibility and practicability, multi-crew execution is considered and the logic relation between units is allowed to be changed arbitrarily. That is, soft logic is considered.

This paper proposes a multi-objective mixed-integer linear programming model with the capability of yielding the optimal tradeoff among three conflicting objectives. An efficient version of the e-constraint algorithm is customized to solve the model. This model is validated based on two case studies involving a small-scale and a practical-scale project, and the influence of using soft logic on project duration and total cost is analyzed via computational experiments.

Using soft logic provides more flexibility in minimizing project duration, work interruptions and TPC, especial for non-typical projects with a high percentage of non-typical activities.

The main limitation of the proposed model fails to consider the learning-forgetting phenomenon, which provides space for future research.

This study assists practitioners in determining the “most preferred” schedule once additional information is provided.

This paper presents a new soft logic-based mathematical programming model to schedule repetitive projects with the goal of optimizing three conflicting objectives simultaneously.

Because of indeterminateness of the environment and delay of the communication, deep space spacecraft is required to be autonomous. Planning technology is studied in order to realize the spacecraft autonomy. First, a multi‐agent planning system (MAPS) based on temporal constraint satisfaction is proposed for concurrency and distribution of spacecraft system. Second, timeline concept is used to describe simultaneous activity, continue time, resource and temporal constraints. Third, for every planning agent in the MAPS, its layered architecture is designed and planning algorithm based on the temporal constraint satisfaction is given in detail. Finally, taking some key subsystems of deep space explorer as an example, the prototype system of MAPS is implemented. The results show that with the communication and cooperation of the planning agents, the MAPS is able to produce complete plan for explorer mission quickly under the complex constraints of time and resource.

This paper first examines how changes in the real effective exchange rate and its volatility affect the exporting activities of firms. Next, it investigates whether exchange rate volatility (EXRV) affects the export behavior of financially constrained and unconstrained firms differently. Finally, it examines the role of financial development in mitigating the effects of EXRV and financial constraints on firms' exports.

The empirical analysis of the paper is based on a wide panel of Pakistani nonfinancial firms listed at the Pakistan Stock Exchange during the period 2001–2016. To mitigate the problem of endogeneity and to take into account the dynamic nature of the empirical model, the authors apply the robust two-step system-GMM estimator developed by Blundell and Bond (1998). To examine the role of credit constraints, firm-year observations are sorted as financially constrained and unconstrained based on the median value of three alternative measures: the liquidity ratio, the dividend payout ratio and the Whited and Wu (WW) index.

The results reveal that an increase in the real effective exchange rate has a positive and significant impact on firms' exports. However, the results show that the EXRV is significantly and negatively related to exporting decisions, suggesting firms considerably decrease their exports during periods of increased unpredictable variations in exchange rates. The findings also suggest that compared to financially constrained firms, the adverse effect of EXRV on exports is weaker for financially unconstrained firms. This finding implies that firm-level financial constraints unfavorably impact exports by making exporting more sensitive to the EXRV. Finally, the findings indicate that financial development not only positively affects firms' exports but also plays a vital role in declining the adverse effects of EXRV on firm-level exports. Specifically, the results show that financial development decreases the negative impact of EXRV on exports for both financially constrained and unconstrained firms. However, the moderating role of financial sector development is higher for financially unconstrained firms.

Notwithstanding that the authors present robust and strong empirical evidence of the effects of EXRV on exporting and on the role of both firm-level financial constraints and financial sector development in formulating these effects, there are some limitations of the study. The authors use a single proxy for measuring financial sector development. However, one may construct an index for the financial sector developed using principal component analysis (PCA) by considering different measures of financial development. The authors use three different measures of financial constraints. Nonetheless, more sophisticated techniques such as switching regression can be used to endogenously determine whether firms are financially constrained. Moreover, an examination of the asymmetric effects of EXRV on exporting across different industries would also be worthwhile.

From a policy point of view, the results suggest that the development of the financial sector and the strategies to lessen credit constraints faced by firms will help in mitigating the adverse effects of the EXRV on the exporting behavior of firms in Pakistan. The findings also suggest that managers in financially constrained firms should apply appropriate hedging strategies to hedge exchange rate risks. Finally, the findings suggest that investors should take into consideration exchange rate dynamics and firms' financial constraints while investing in exporting firms' stocks.

Since the findings suggest that financially constrained firms' exports are more exposed to EXRV, managers of such exporting firms are suggested to apply effective and suitable currency risk-minimizing hedging instruments for enhancing their exports. The government should also implement economic and financial policies in such a way that they should help in reducing volatilities of exchange rates and in turn, encouraging firms to export more. Definitely, any policy, at both government and firm level, favoring exporting and export-oriented growth will not only help in overcoming the problem of a persistent and wide trade deficit but also help society by providing more employment and investment opportunities.

Recently, Pakistan has experienced significant declines in foreign reserves, persistent political unrest and enlarged trade deficits. All these have increased the uncertainty about the exchange rate. Therefore, it is valuable to know the EXRV effects on firms' exporting activities. Second, Pakistani firms face more financial constraints, and thus, the influence of financial constraints in formulating the volatility effects on exporting would be worth exploring. Finally, no research has yet taken place to scrutinize the role of financial development in mitigating the adverse effects of EXRV and financial constraints on exporting activities. This paper provides firsthand empirical evidence on the role of financial constraints and financial sector development in formulating the EXRV impacts on firm-level exports in Pakistan.

This research investigates the link between corporate social responsibility (CSR) activities and bank risk-taking in Vietnam and introduces the constraint factor to see whether this link alters with different levels of constraint.

Using a sample of commercial banks in Vietnam from 2008 to 2017, this study employs two-step system generalized method of moments (Sys GMM) with a finite sample correction mechanism to estimate the models.

The results suggest that CSR activities reduce bank risk-taking, and this relationship is only present in the case of financially constrained banks. Unconstrained banks, on the other hand, are more likely to invest in unnecessary CSR, thus reducing bank performance and increasing bank risk-taking.

The first implication from this study is that CSR activities might be considered as a risk-mitigating tool and should be invested in that respect. Secondly, regulatory units and investors should be more cautious about CSR expenditures since this type of spending could increase default risk, especially for banks with easy access to external financing. One particular limitation of this study is the low number of observations available for banks in Vietnam. Future studies could use texture analysis to expand the sample or consider macro-level governance characteristics to examine which factors might modify the relationship between CSR and bank risk.

Very limited studies discussed the link between corporate social responsibility and bank performance and bank risk. There are even fewer papers examining the relationship between CSR and risk, and most of these papers deal with advanced economies. Furthermore, no studies investigate the interaction effect of CSR and financial constraint, which should be prevalent in developing countries on bank risk. As a consequence, the current study seeks to verify the impact of financial constraints on the link between CSR and bank risk.

The purpose of this study is to automatically generate a construction schedule by extracting data from the BIM (Building Information Modeling) model and combining an ontology constraint rule and a genetic algorithm (GA).

This study developed a feasible multi-phase framework to generate the construction schedule automatically through extracting information from the BIM, utilizing the ontology constraint rule to demonstrate the relationships between all the components and finally using the GA to generate the construction schedule.

To present the functionality of the framework, a prototype case is adopted to show the whole procedure, and the results show that the scheme designed in this study can quickly generate the schedule and ensure that it can satisfy the requirements of logical constraints and time parameter constraints.

A proper utilization of conceptual framework can contribute to the automatic generation of construction schedules and significantly reduce manual errors in the Architectural, Engineering, and Construction (AEC) industry. Moreover, a scheme of BIM-based ontology and GA for construction schedule generation may reduce additional manual work and improve schedule management performance.

The hybrid approach combines the ontology constraint rule and GA proposed in this study, and it is an effective attempt to generate the construction schedule, which provides a direct indicator for the schedule control of the project.

In this study, the data application process of the BIM model is divided into four modules: extraction, processing, optimization, and output. The key technologies including secondary development, ontology theory, and GA are introduced to develop a multi-phase framework for the automatic generation of the construction schedule and to realize the schedule prediction under logical constraints and duration interference.

Considers the resource‐constrained project scheduling problem where cash inflows and outflows are tied to the occurrence of events. The objective is the maximization of the project net present value (NPV) as well as the minimization of project tardiness in the presence of a project due date. Develops hybrid scheduling rules with both NPV and tardiness considerations to enhance both objectives. Experiments extensively with a set of benchmark problems originally designed for the objective of minimizing the project duration. Demonstrates that thje hybrid rules developed here are superior in performance with respect to both objectives when compared with well known rules which are developed for the two objective of minimizing the project duration. Demonstrates that the hybrid rules developed here are superior in performance with respect to both objectives when compared with well‐known rules which are developed for the two objectives taken individually. Furthermore, the iterative algorithm improves the performance of all tested rules significantly.