RENT-SEEKING DECISIONS OF THE MAIN PARTICIPANTS IN CONSTRUCTION PROJECTS BASED ON EVOLUTIONARY-GAME AND SYSTEM DYNAMICS

The performance of a construction project can be severely harmed by its participants’ rent-seeking. In order to prevent such attempt, this research integrates the evolutionary game theory with system dynamics method to simulate the impact of the change of some factors that may cause/reduce rent-seeking. Based on the analysis of the behavioral characteristics and interactive relationships of the main participants (the owner, supervisor, and contractor), an evolutionary game model is constructed and simulated with the method of system dynamics based on the replication dynamic equation of the mixed strategy solution of the three-party static game model. By assigning the parameters of project scale, supervision likelihood, supervision success rate, supervision cost, and penalty intensity, the interaction mechanism of the participants on each factor is revealed through a case-based simulation. The results show that the impacts of these factors on participants’ rent-seeking decisions are significantly different. Furthermore, some management suggestions are provided to prevent rent-seeking for project owner according to the research conclusions. This research can help the project owners take proper measures to prevent rent-seeking of the supervisors and the contractors to improve the performances of the projects.

Simulation Model for the Estimation of Energy Consumption of the Baggage Handling System in the Landside Area of the Airport

The purpose of this paper was to develop a simulation model to perform a sensitivity analysis of the energy consumption of an airport baggage handling system to a change in resource allocation strategy. This is a novel approach as this aspect has not been considered until now. This aspect, in turn is very important in terms of sustainability. The paper presents the detailed structure of the model and the data on which it operates. It is universal and can be the basis for analyzing any structure of the baggage handling system in the landside of any airport. An example analysis has shown that even up to 35% benefits can be gained by using the model. Three scenarios were analyzed in the model (dedicated check-in desks scenario, common desks scenario and mixed strategy scenario). However, the model is not limited to these strategies and any resource allocation is possible. The model is useful both for planning a new system as well as optimizing an existing system during its operation.

Decision-making method based on game theory and grey theory in a single-value neutrosophic environment and its application to typhoon disaster assessment

PurposeThe Chinese believe that “man will conquer the sky” and “fighting with the sky brings endless joy”. Considering that disaster assessment can be regarded as a two-person, zero-sum game problem between nature and human beings, this paper proposes a multi-attribute decision-making method based on game theory and grey theory in a single-value neutrosophic set environment. Due to the complexity and uncertainty of the decision-making environment, the method builds a decision matrix based on single-valued neutrosophic numbers.Design/methodology/approachFirst, the authors use the single-value neutrosophic information entropy to calculate the attribute weights and the weighted decision matrix. Second, the optimal mixed strategy method based on linear programming solves the optimal mixed strategy for both sides of the game so that the expected payoff matrix can be obtained. Finally, grey correlation analysis is used to obtain the closeness coefficient of each alternative based on the expectation payoff matrix to identify the ranking result of the alternative.FindingsAn example is used to verify the effectiveness of the proposed method, and its rationality is verified through a comprehensive comparison and analysis of the various aspects.Practical implicationsThe proposed decision-making method can be applied to typhoon disaster assessment. Such assessment results can provide intelligent decision support to the relevant disaster management departments, thereby reducing the negative impact of typhoon disasters on society, stabilizing society and improving people's happiness. Further, the method can be used for decision-making, recommendation and evaluation in other fields.Originality/valueThe proposed method uses single-value neutrosophic numbers to solve the information representation problem of decision-making in a complex environment. Under a new perspective, game theory is used to handle the decision matrix, while grey relational analysis converts inexact numbers to exact numbers for comparison and sorting. Thus, the proposed method can be used to make reasonable decisions while preserving information to the extent possible.

CHOICE OF LOCOMOTIVE PARK MAINTENANCE STRATEGY WHEN INTRODUCING THE SERVICE

In operation, sometimes there are situations of uncertainty in assessing the technical condition of locomotive equipment and at the same time choosing the optimal strategy for its maintenance, including the possibility of using the service. Application of the concept of service gives the chance to stimulate work of all divisions of locomotive economy, to save all kinds of resources for operation of locomotives. According to this, the article substantiates the choice of strategy for maintaining the locomotive fleet using the provisions of the theory of statistical solutions. Game theory approaches were used to theoretically substantiate the transition to a service for decision-making in conflict situations and to determine the optimal strategy of behavior of each of the participants in this situation. Approaches to the choice of strategy for the maintenance of the locomotive fleet during the introduction of the service on the basis of the provisions of the theory of strategic games on the criterion of maximum efficiency were considered. It is shown on examples of the decision of some problems of a choice of maintenance strategy of locomotives for various industrial situations. It is concluded that a mixed strategy describes different situations best and allows to made rational decisions. It is also noted that the most effective approach to concretize the algorithm of actions is the complex application of the theory of strategic decisions, the theory of fuzzy sets, the theory of pattern recognition.

Polymer Solution with Very Low Relaxation Time: A Combined Numerical-Experimental Determination Strategy

For very low relaxation time (i.e. lesser than a microsecond) viscoelastic fluid experimental determination is difficult, if not impossible. In the present work the relaxation time measurement of a weakly elastic polymer solution, too low to be measured using classical rheometry techniques, is assessed using a mixed experimental-numerical strategy. First the fluid is rheologically assessed, by measuring its shear viscosity, surface tension and density. Then the relaxation time is determined by comparing the jetting of polymer solution from a Continuous Ink-Jet (CIJ) device experimentally and numerically. The numerical approach is first validated using test case and a viscoelastic Oldroyd-B model is then used to model the experimental solution. The relaxation time is then a parameter allowing us to fit numerical simulation onto experimental results. This mixed strategy is particularly convenient for weakly elastic solution for which physical parameters can not be measured using experimental rheometry setup.

Tax Competition between Symmetric Countries for Large Asymmetric Investors

In a dynamic two-period game between two symmetric countries, we show that a unique subgame-perfect equilibrium arises during the initial stage of the game. A mixed taxation regime arises in the equilibrium where one country adopts a non-preferential taxation regime while its competitor adopts a preferential taxation regime. The country with a non-preferential taxation regime earns a higher tax revenue compared to the country with a preferential taxation regime. A tax holiday does not arise during the initial stage of the game when the size of the mobile capital base that enters during the later stage is considerably larger than the size of the mobile capital base that enters the economy during the initial stage. We provide the complete characterization and proof of the uniqueness of the mixed strategy Nash equilibrium.JEL classification: F21, H21, H25, H87

Phenotypic plasticity, life cycles, and the evolutionary transition to multicellularity

SUMMARYUnderstanding the evolutionary transition to multicellularity is a key problem in evolutionary biology (1,2). While around 25 independent instances of the evolution of multicellular existence are known across the tree of life (3), the ecological conditions that drive such transformations are not well understood. The first known transition to multicellularity occurred approximately 2.5 billion years ago in cyanobacteria (4–6), and today’s cyanobacteria are characterized by an enormous morphological diversity, ranging from single-celled species over simple filamentous to highly differentiated filamentous ones (7,8). While the cyanobacterium Cyanothece sp. ATCC 51142 was isolated from the intertidal zone of the U.S. Gulf Coast as a unicellular species (9), we are first to additionally report a phenotypically mixed strategy where multicellular filaments and unicellular stages alternate. We experimentally demonstrate that the facultative multicellular life cycle depends on environmental conditions, such as salinity and population density, and use a theoretical model to explore the process of filament dissolution. While results predict that the observed response can be caused by an excreted compound in the medium, we cannot fully exclude changes in nutrient availability (as in (10,11)). The best fit modeling results demonstrate a nonlinear effect of the compound, which is characteristic for density-dependent sensing systems (12,13). Further, filament fragmentation is predicted to occur by means of connection cleavage rather than by cell death of every alternate cell. The phenotypic switch between the single-celled and multicellular morphology constitutes an environmentally dependent life cycle, which likely represents an important step en route to permanent multicellularity.

Selection of Playing Style in Table Tennis Depending on the Complex of Psychophysiological Indices

The Research Purpose is typological predisposition and psychomotor indices studying directed on the table tennis playing style formation. The Methodology of the Research. 114 male tennis players: 5 Masters of Sports of International Class, 39 Masters of Sports, 38 Candidates for Masters, 32 athletes of the first category have been examined. Typological peculiarities, in particular, strength of nervous system relative to excitation; mobility-inertness of excitation and inhibition, external and internal balance have been studied. The Research Results. An offensive strategy is associated with the following typological features: the nervous system of high and average strength (amid the common to all tennis players’ weakness of the nervous system) as a reflection of their predominance of excitation in the external balance. Defensive strategy players are characterized by a high resistance to monotony, a greater expression of the nervous system weakness, and a predominance of inhibition according to internal balance. Mixed strategy players are distinguished by a relatively higher (than in defenders) strength of the nervous system, balance of excitation and inhibition processes, and greater mobility of excitation and inhibition processes. The offensive strategy players are characterized by higher motion pace and auto pace as compared to those of mixed and especially defensive strategy play. Defensive strategy players` time of simple and complex visual-motor reaction is significantly higher as compared to those who prefer the offensive strategy. Defensive and mixed strategy players have got the deferred reactions tend to dominate during the response to moving object, whereas offensive strategy players – premature responses are observed. In order to adequately perceive the current situation and have more time to decide on the proper response action, they have to move further way from the tennis table than the offensive strategy players. Conclusions: Study has conducted for examination of typological predispositions and psychomotor indices that condition directed formation of table tennis playing style. It is important direction of training.

Sociodynamics of Students’ Digital Capital in the Context of the COVID-19 Epidemiological Crisis: an Experience of a Mixed Strategy of Empirical Research

Introduction. The sociodynamics of students’ digital capital in the context of an epidemiological crisis has acquired special characteristics. The speed, focus and technologies for the formation of digital capital have changed significantly and are expressed in new content features and characteristi cs of sociodynamics.Methodology and sources. An integrative approach to the study and analysis of the digital capital sociodynamics is used, which consists a set of theoretical and methodological positions in the study of digital capital proposed by resea rchers earlier. An approach to the sociological interpretation of the concept of digital capital, which is characterized by systemic and integrative characteristics, is presented. The formed theoretical and methodological platform served as the basis for c onstructing an empirical research methodology.Results and discussion. Methodological approaches to the digital capital definition as an object of research are generalized. The contradictions and fragmentation in the interpretation of digital capital in private research and the relevance of sociological understanding of the essence of digital capital are shown. The tendencies and trends of the sociodynamics of digital capital during the pandemic have been empirically confirmed.Conclusion. The article presents some trends in the sociodynamics of students’ digital capital in a pandemic: first, the stimulating role of the pandemic in the development of digital competencies; secondly, changes in the direction of mastering digital competencies; third, analysis of the activity and intensity of changes in digital competencies; fourth, the intensification of the development of digital technologies related to the social aspects of interaction in the context of a lockdown.