Modified extragradient methods for solving variational inequalities

AbstractIn this paper, we propose two methods for solving variational inequalities. In the first method, we modified the extragradient method by using a new step size while the second method can be viewed as an extension of the first one by performing an additional projection step at each iteration and another optimal step length is employed to reach substantial progress in each iteration. Under certain conditions, the global convergence of two methods is proved. Preliminary numerical experiments are included to illustrate the efficiency of the proposed methods

The Regulatory Strategy in Emissions Trading System under Costly Enforcement

In a two-stage dynamic game of regulator and polluting firms, the optimal regulatory strategy to achieve a fixed aggregate emissions target cost-effectively in emissions trading system was studied under the context of costly monitoring and sanctioning, including the monitoring level, the aggregate supply of permits, and the penalty shape for noncompliance. Based on gaming analysis, a heterogeneous agent-based experiment platform for regional emissions trading system was established using computational experiment. Then further analyses were done from perspectives of dynamic and bounded rationality. The results show that the optimal strategy to achieve target is to induce full compliance. This is not simply setting severe punishment, but seeking tradeoff between the level of monitoring and punishment. Finally, integrating the permit price directly into the penalty shape allows the policy objective to be achieved more cost-effective

Computational Experiment Study on Selection Mechanism of Project Delivery Method Based on Complex Factors

Project delivery planning is a key stage used by the project owner (or project investor) for organizing design, construction, and other operations in a construction project. The main task in this stage is to select an appropriate project delivery method. In order to analyze different factors affecting the PDM selection, this paper establishes a multiagent model mainly to show how project complexity, governance strength, and market environment affect the project owner’s decision on PDM. Experiment results show that project owner usually choose Design-Build method when the project is very complex within a certain range. Besides, this paper points out that Design-Build method will be the prior choice when the potential contractors develop quickly. This paper provides the owners with methods and suggestions in terms of showing how the factors affect PDM selection, and it may improve the project performance

New Analyses of Duopoly Game with Output Lower Limiters

In the real business world, player sometimes would offer a limiter to their output due to capacity constraints, financial constraints, or cautious response to uncertainty in the world. In this paper, we modify a duopoly game with bounded rationality by imposing lower limiters on output. Within our model, we analyze how lower limiters have an effect on dynamics of output and give proof in theory why adding lower limiters can suppress chaos. We also explore the numbers of the equilibrium points and the distribution of conditioned equilibrium points. Stable region of the conditioned equilibrium is discussed. Numerical experiments show that the output evolution system having lower limiters becomes more robust than without them, and chaos disappears if the lower limiters are big enough. The local or global stability of the conditional equilibrium points provides a theoretical basis for the limiter control method of chaos in economic systems

Dry Ports-Seaports Sustainable Logistics Network Optimization: Considering the Environment Constraints and the Concession Cooperation Relationships

In China dry ports enter into a rapid development period now, however for many Chinese dry ports, the operation faces difficulties duo to inefficient logistics networks and cooperation relationship between dry ports and seaports. Focusing on the concession cooperation mechanism of seaports and dry ports, and the environmental constraints (carbon emissions and congestion cost), a bi-objective location-allocation MILP model for the sustainable hinterland-dry ports-seaports logistics network optimization is formulated, aiming at the system logistics costs and carbon emissions to be minimized. Moreover, for the cooperation mechanism of seaports to dry ports, a parameter called cooperation cost concession coefficient is proposed for the optimization model, and a new evaluation method based on the ordered weighted averaging (OWA) operator is used to evaluate it. Then a location-allocation decision-making framework for the hinterland-dry port-seaport logistics network is proposed. The innovative aspect of the model is that it can proposes a effective and environment friendly dry ports location strategic and also give insights into the connective cooperation relationships, and cargo flows of the network. A case study involving configuration of dry ports in Henan Province is conducted, and the model is successfully applied

Emission trading innovation mechanism based on blockchain

The rationality and scientific nature of the emission trading mechanism is the key to the effective implementation of environmental and economic policies. As far as China is concerned, there are phenomena such as information asymmetry, low supervision efficiency, and alienation of government and enterprise behaviors caused by the incomplete mechanism of emission trading in the practice of different pilots. The introduction of blockchain technology can innovate the traditional transaction model and form a decentralized peer-to-peer transaction and a trusted emission trading market. To this end, based on the current emission trading mechanism and the characteristics of blockchain technology, this paper couples the core technologies of blockchain with the functional requirements of application scenarios. Then, an innovative application framework is built based on the consortium blockchain Fabric from three aspects: emission trading supervision, secondary trading market construction, as well as emission trading incentive and punishment mechanisms. Technologies such as the consensus mechanism, smart contract, Merkle tree and asymmetric encryption are comprehensively applied in this process. In the construction of the blockchain framework of the secondary market for emission trading, institutional changes and innovations brought about by the blockchain at various levels are analyzed in terms of participants, transaction processes and the transaction scope. At the same time, smart contract functions and algorithms are designed for the purchase, transfer-out and trading of emission rights, and the operation business logic of the smart contract is analyzed. On the whole, this paper explores the application framework of blockchain technology in the field of emission trading at the macro level, and analyzes the application mechanism of the corresponding technologies of blockchain at each coupling point in the framework at the micro level. The collaborative analysis at the two levels shows that blockchain technology and the requirements of emission trading mechanism can be effectively coupled, and the application of blockchain technology can promote the effective supervision of enterprises' emission behavior, making the processes of the purchase, transfer and transaction of emission rights intelligent and automated, and providing technical support for cross-regional emission trading to reduce transaction costs and management complexity. In addition, the issuance of emission credits based on smart contract will be a new incentive for companies to actively participate in transactions. Based on the above analysis, this paper believes that the innovative application of blockchain technology is of great significance in the promotion of the market-based allocation of element of emission trading and the rational allocation of environmental resources. It will lead to a major breakthrough in the traditional trading system in terms of trading modes, forming a value transmission network of environmental resources between the government and polluters

Analysis of Price Stackelberg Duopoly Game with Bounded Rationality

The classical Stackelberg game is extended to boundedly rational price Stackelberg game, and the dynamic duopoly game model is described in detail. By using the theory of bifurcation of dynamical systems, the existence and stability of the equilibrium points of this model are studied. And some comparisons with Bertrand game with bounded rationality are also performed. Stable region, bifurcation diagram, The Largest Lyapunov exponent, strange attractor, and sensitive dependence on initial conditions are used to show complex dynamic behavior. The results of theoretical and numerical analysis show that the stability of the price Stackelberg duopoly game with boundedly rational players is only relevant to the speed of price adjustment of the leader and not relevant to the follower’s. This is different from the classical Cournot and Bertrand duopoly game with bounded rationality. And the speed of price adjustment of the boundedly rational leader has a destabilizing effect on this model

Analysis of Complexity of Unsafe Behavior in Construction Teams and a Multiagent Simulation

The processes in construction are more likely than others to breed unsafe behaviors, and the consequences of these actions can be serious. This paper first reviews the research status on unsafe behavior in construction teams. It then analyzes the complex mechanisms that lead to unsafe behavior and constructs a three-layer structural model based on agent-based modeling (ABM) technology. This modeling deals with complexity and elaborates on key points and potential research ideas in the study of unsafe behavior in construction teams. Using the ABM method, the effects of different incentive strategies on the safe behavior of construction teams under different management scenarios were studied. The results showed that when members have a fair perception of the situation, the effect of the excess performance reward distribution, according to the member’s safety awareness level, is better than the average distribution effect. This is the case whether the member’s safety behavior level is positively or negatively related to the member’s safety awareness level. This study proves the feasibility, validity, and universality of the three-layer structural model. It also reaches certain management conclusions and ideas for further development. The purpose of this paper is to provide a reference for research on the containment and prevention of unsafe behavior in construction teams