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In the rapidly deploying process of the unmanned aerial vehicle with folding wings, the aerodynamic characteristics could be largely different owing to the effects of deformation rate and the aerodynamic interference. The investigation on the unsteady aerodynamics is of great significance for the stability analysis and control design. The lifting-line method and the vortex-lattice method are improved to calculate the unsteady aerodynamics in the morphing stage. It is validated that the vortex-lattice method predicts the unsteady lift coefficient more appropriately than the lifting-line method. Different tandem wing configurations with deployable wings are simulated with different deformation rates during the morphing stage by the vortex-lattice method. As results indicated, the unsteady lift coefficient and the induced drag of the fore wing rise with the deformation rate increasing, but it is reversed for the hind wing. Additionally, the unsteady lift coefficient of the tandem wing configuration performs well with a larger stagger, a larger magnitude of the gap and a larger wingspan of the fore wing; however, the total induced drag has a larger value for the configuration that the two lifting surfaces with the same wingspans are closer to each other.

In this paper, we introduce a class of new selection and routing problems, and name it as the traveling salesman problem with profits and stochastic customers (TSPPSC), which is an extension of the traveling salesman problem with profits (TSPP). The class of new problems is put forward to address how to deal with stochastic customer presence under the environment in which an associated profit is obtained once a customer is visited. It is defined on a complete graph in which profits are associated with the vertices and travel costs are associated with the edges. Each vertex (customer) has a probability of requiring a visit. The objective is the simultaneous optimization of the expected collected profits and expected travel costs. According to the way the two objectives (profits and travel costs) are addressed, TSPPSC is categorized into three subproblems. Mathematical formulations are provided for these problems and a genetic algorithm is proposed to solve one of these subproblems. Computational experiments conducted on several sets of instances show a good performance of the proposed algorithm.

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In this paper, the authors study the capacity decision problem in an express delivery supply chain consisting of an online retailer and an express delivery provider where products sold by the online retailer are delivered by the express delivery provider to end customers. Unlike the case of the traditional manufacturer-retailer channels, the delivery capacity is a kind of “service product” that cannot be inventoried. To avoid the risk of unprofitable capacity, the delivery provider tends to build a limited delivery capacity which is smaller than the system-wide optimal capacity. To solve such a problem, the authors investigate the capacity coordination issue in this service supply chain using option contracts. By allowing the online retailer to reserve the capacity in advance, the delivery provider could rent a part of capacity which surpasses its self-owned capacity from a third party logistics. It is demonstrated that, compared with the benchmark based on a newsvendor model, option contracts can coordinate the delivery service supply chain. The authors also figure out the feasible option contracts that improve member's expected profit and show the degree of improvement that could be achieved.

Due to the lack of matched dedicated small satellite launch vehicles, launch opportunities as a rideshare or piggyback using a highly reliable launch system has become increasingly important for small satellite developers. The objective of this paper is to provide an aggregated value method as a strategy for developers to evaluate launch opportunities, as well as an approach for the launchers to capture the market dynamics. Based on an up-to-date launch record, a reliable launch database for multi-attribute evaluation is established. Efforts are made to quantify the abstract and concrete attributes of launch systems. An aggregated preference value model is developed, translating different inherited capabilities of launch systems into integrated preference value as a reference for decision-making. The preference values of the launch opportunities of different launch vehicles are explored in a case study by the method proposed, and its feasibility and applicability for small satellite launch system evaluation tasks is validated.

NK model describes a system of N elements. The complexity of the system is modeled as the interdependency among its elements. Such interdependency is represented by parameter K, which denotes the number of elements that affect the function of a particular element. NK model can be used to simulate the adaptive behavior through the fitness landscape. The authors collected data from 217 employees in five organizations from different industries in China. They empirically examine the role of six factors, namely, proactive personality, creative process engagement, coworker support, supervisor support, freedom or autonomy and resource supply, in developing employee creativity. Based on empirical findings, the authors then use the NK model to simulate the process of adaption of employee creativity. Their simulation results show the different adaptive processes of employee creativity in the five organizations from different industries. The theoretical and practical implications of their study are discussed in the final part of this paper.