This paper proposed a state-of-the-art local search for solving Flexible Demand Assignment problem (FDA) which considers the balance between revenue and cost in demand assignment. Different than the published studies, our research splits the FDA problem into three core subproblems as operators for neighborhood construction. The three specified subproblems One Bin Repack, Two Bins Repack and Unp...

This paper presents a MIP model for a locomotive routing and scheduling problem from the domain of freight railways. Innovative features of the model include the use of binary variables to separate the integer and continuous parts of the problem to maintain the flow character of the integer part of the problem. The model has been developed with, and has found practical Green Cargo, the largest ...

The condition of locomotive bearings, which are essential components in trains, is crucial to train safety. The Doppler effect significantly distorts acoustic signals during high movement speeds, substantially increasing the difficulty of monitoring locomotive bearings online. In this study, a new Doppler transient model based on the acoustic theory and the Laplace wavelet is presented for the ...

A branch and bound algorithm for finding the minimal cost symmetric assignment is discussed. The matching problem in graph theory and the Chinese postman puzzle are all special cases of the symmetric assignment problem, and hence this algorithm can be applied to solve them.

The Aircraft Assignment problem is the problem of assigning flights to aircraft in such a way that some operational constraints are satisfied, and possibly that some objective function is optimized. We propose an approach to aircraft assignment which captures all operational constraints, including minimum connection times, airport curfews, maintenance, and preassigned activities. It also allows...

Changing the QAP's hard definition such that the facilities M are allowed to be mapped by a (single-valued, not necessarily injective) function π into the set of possible locations Y subject to a relation Π, π ⊆ Π, it arises the Semi-QAP that might be regarded as a relaxation of the QAP. In contrast to the Tree-QAP (flow graph F is a tree) the corresponding Semi-Tree-QAP is solvable in polynomi...

The Japanese Orthopaedic Association has proposed the term "locomotive syndrome" to designate a condition that places a person at high risk for long-term care. However, in daily clinical practice, even when a diagnosis of locomotive syndrome is made, exercise therapy often cannot be successfully performed in some patients owing to their lack of motivation. We speculated that locomotive syndrome...

In this paper we present the problem of designing a three level hub center network. In our network, the top level consists of a complete network where a direct link is between all central hubs.  The second and third levels consist of star networks that connect the hubs to central hubs and the demand nodes to hubs and thus to central hubs, respectively. We model this problem in an incomplete net...

Task assignment problem (TAP) involves assigning a number of tasks to a number of processors in distributed computing systems and its objective is to minimize the sum of the total execution and communication costs, subject to all of the resource constraints. TAP is a combinatorial optimization problem and NP-complete. This paper proposes a hybrid meta-heuristic algorithm for solving TAP in a ...

BACKGROUND Motor dysfunction is a major reason why the elderly lose their independence in their daily lives. The concept of locomotive syndrome has been proposed to describe the risk of mobility dependence caused by various locomotive organ disorders. The preservation of locomotive organs is now socially important in the middle-aged and geriatric population. Therefore, it is important to establ...