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Word Sense Disambiguation (WSD) is the task to determine the sense of an ambiguous word in a given context. Previous approaches for WSD have focused on supervised and knowledge-based methods, but inter-sense interactions patterns or regularities for disambiguation remain to be found. We argue the following cause as one of the major difficulties behind finding the right patterns: for a particular context, the intended senses of a sequence of ambiguous words are dependent on each other, i.e. the choice of one word's sense is associated with the choice of another word's sense, making WSD a combinatorial optimization problem.In this work, we approach the interactions between senses of different target words by a Quadratic 0-1 Integer Programming model (QIP) that maximizes the objective function consisting of (1) the similarity between candidate senses of a target word and the word in a context (the sense-word similarity), and (2) the semantic interactions (relatedness) between senses of all words in the context (the sense-sense relatedness)., Comment: 9 pages, 3 figures

This paper studies the problem of optimizing the train formation plan and traffic routing (TFP&TR) simultaneously. Based on the previous research of TFP&TR with determinate parameters, we consider the fluctuation of flows and associate the elastic features of yard capacities and link capacities. To demonstrate such elastic peculiarities, the fuzzy theory is introduced and the membership function is designed to designate the satisfaction degree for the volumes of traffic flows. A non-linear integer programming model is developed considering various operational requirements and a set of capacity constraints, including link capacity, yard reclassification capacity and the maximal number of blocks a yard can be formed, while trying to minimize the total costs of accumulation, reclassification, and transportation.

Some large freight railroads ship a number of shipments over the rail network annually. To reduce unnecessary reclassifications of shipments on their routes, each railroad is willing to operate the entire train for an individual shipment. In other words, the motivation for providing the entire train service lies in a simple realization that door to door transportation (directly from origin to destination) can reduce operating costs by decreasing classification. However, this mode will increase inventory costs for customers when commodities are transported by low frequency entire train services. Thus, this study proposes the trade-off strategy to keep a balance between saving operating costs of railroads and increasing inventory costs of customers. We analyze the revenue and losses after a shipment shifting from the transfer transportation which contains a series of train services to the direct transportation by entire train service., Comment: 14 pages, 2 figures

In this paper, we reveal the depreciation mechanism of representative money (banknotes) from the perspective of logistics warehousing costs. Although it has long been the dream of economists to stabilize the buying power of the monetary units, the goal we have honest money always broken since the central bank depreciate the currency without limit. From the point of view of modern logistics, the key functions of money are the store of value and low logistics (circulation and warehouse) cost. Although commodity money (such as gold and silver) has the advantages of a wealth store, its disadvantage is the high logistics cost. In comparison to commodity money, credit currency and digital currency cannot protect wealth from loss over a long period while their logistics costs are negligible. We proved that there is not such honest money from the perspective of logistics costs, which is both the store of value like precious metal and without logistics costs in circulation like digital currency. The reason hidden in the back of the depreciation of banknotes is the black hole of storage charge of the anchor overtime after digitizing commodity money. Accordingly, it is not difficult to infer the inevitable collapse of the Bretton woods system. Therefore, we introduce a brand-new currency named honest devalued stable-coin and built a attenuation model of intrinsic value of the honest money based on the change mechanism of storage cost of anchor assets, like gold, which will lay the theoretical foundation for a stable monetary system.

In order to reduce the carbon emission, the related government departments encourage road freights to be transferred more by railway transportation. In China freight transport system, the road transportation is usually responsible for the freights that are in a short distance or the ones with high value-added. To transfer more high value-added freights from highway to railway, except the transportation expenses of railway have an advantage over the road, the transportation time is of certain competitive force as well. Therefore, it is very essential for railway to provide freight train products that are of competitive power. Under such circumstance, a multi-objective programming model of optimizing the rail express train network is devised in this work on the basis of taking both road and railway transportation modes into account. The aims of optimization are to minimize the operation costs of rail trains, and to maximize the railway transport revenue. In a network with a given set of express train services, either the all-or-nothing (AON) method or the logit model can be employed when assigning high value-added freights. These two flow assignment patterns are investigated in this work., Comment: 10 pages, 2 figures, 1 table

The Electric Multiple Unit (EMU) circulation plan is the foundation of EMU assignment and maintenance planning,and its primary task is to determine the connections of trains in terms of train timetable and maintenance constraints. We study the problem of optimizing EMU circulation plan, and a 0-1 integer programming model is presented on the basis of train connection network design. The model aims at minimizing the total connection time of trains and maximizing the travel mileage of each EMU circulation, and it meets the maintenance constraints from two aspects of mileage and time cycle. To solve a large-scale problem efficiently, we present a heuristic algorithm based on particle swarm optimization algorithm. At last, we conclude the contributions and directions of future research., Comment: 17 pages, 3 figures

With the expansion of high-speed railway network and growth of passenger transportation demands, the fleet size of electric multiple unit (EMU) in China needs to be adjusted accordingly. Generally, an EMU train costs tens of millions of dollars which constitutes a significant portion of capital investment. Thus, the prediction of EMU fleet size has attracted increasing attention from associated railway departments. First, this paper introduces a typical architecture of convolutional neural network (CNN) and its basic theory. Then, some data of nine indices, such as passenger traffic volume and length of high-speed railways in operation, is collected and preprocessed. Next, a CNN and a backpropagation neural network (BPNN) are constructed and trained aiming to predict EMU fleet size in the following years. The differences and performances of these two networks in computation experiments are analyzed in-depth. The results indicate that the CNN is superior to the BPNN both in generalization ability and fitting accuracy, and CNN can serve as an aid in EMU fleet size prediction., Comment: 13 pages,7 figures

The courier industry is one of the most essential parts of the modern logistics. Meanwhile, the courier transportation network is one of the most important infrastructures of courier enterprises to take participate into operation. This paper presents a combinatorial optimization model for the courier transportation network design problem, and the aim of network optimization is to determine the transportation organization mode for each courier flow. A nonlinear zero-one integer programming model is formulated to describe the problem, the objective function of the model is intended to minimize the total cost including the accumulation cost, the transportation cost and the transfer cost. Also, we take transportation modes and types of transport carriers into account in the objective function. The constraints of the combinatorial optimization model contain capacities of transfer and sorting centers and delivery dates predefined., Comment: 8 pages, 1 figure, 1 table

Freight train services in a railway network system are generally divided into two categories: one is the unscheduled train, whose operating frequency fluctuates with origin-destination (OD) demands; the other is the scheduled train, which is running based on regular timetable just like the passenger trains. The timetable will be released to the public if determined and it would not be influenced by OD demands. Typically, the total capacity of scheduled trains can usually satisfy the predicted demands of express cargos in average. However, the demands are changing in practice. Therefore, how to distribute the shipments between different stations to unscheduled and scheduled train services has become an important research field in railway transportation. This paper focuses on the coordinated optimization of the rail express cargos distribution in two service networks. On the premise of fully utilizing the capacity of scheduled service network first, we established a Car-to-Train (CTT) assignment model to assign rail express cargos to scheduled and unscheduled trains scientifically. The objective function is to maximize the net income of transporting the rail express cargos. The constraints include the capacity restriction on the service arcs, flow balance constraints, logical relationship constraint between two groups of decision variables and the due date constraint. The last constraint is to ensure that the total transportation time of a shipment would not be longer than its predefined due date. Finally, we discuss the linearization techniques to simplify the model proposed in this paper, which make it possible for obtaining global optimal solution by using the commercial software., Comment: 12 pages, 1 figure

Classification yards are crucial nodes of railway freight transportation network, which plays a vital role in car flow reclassification and new train formation. Generally, a modern yard covers an expanse of several square kilometers and costs billions of yuan, i.e., hundreds of millions of dollars. The determination of location and size of classification yards, which is a location-allocation problem with railway characteristics, is not only related to building or improving cost, but also involved with train connecting service (TCS) plan. This paper proposed a bi-level programming model for this problem. The upper-level is intended to find an optimal building or improving strategy for potential nodes, and the lower-level aims to obtain a least costly TCS plan considering reclassification cost and accumulation delay, when the building or improvement plan is given by the upper-level. The model is constrained by capital budget, classification capacity, the number of available tracks, etc., Comment: 12 pages, 1 table

This paper considers the simultaneous high-speed train assignment and maintenance scheduling problem. For the maintenance scheduling module, our focus is the second-level maintenance, which is carried out once a month on average. We propose a binary non-linear programming model to mathematically describe the problem. The objective aims to minimize the mileage losses for all high-speed trains and the constraints cover various operational requirements and capacity restrictions. To model the difficult operational requirements, a novel cumulative mileage update function is developed; meanwhile, to describe the depot maintenance capacity restriction, we employ a state function that is able to identify whether a train is in the maintenance state or in the operation state., Comment: 12 pages, 2 figures and 1 table

An essential issue that a freight transportation system faced is how to deliver shipments (OD pairs) on a capacitated physical network optimally; that is, to determine the best physical path for each OD pair and assign each OD pair into the most reasonable freight train service sequence. Instead of pre-specifying or pre-solving the railcar routing beforehand and optimizing the train formation plan subsequently, which is a standard practice in China railway system and a widely used method in existing literature to reduce the problem complexity, this paper proposes a non-linear binary programming model to address the integrated railcar itinerary and train formation plan optimization problem. The model comprehensively considers various operational requirements and a set of capacity constraints, including link capacity, yard reclassification capacity and the maximal number of blocks a yard can be formed, while trying to minimize the total costs of accumulation, reclassification and transportation. An efficient simulated annealing based heuristic solution approach is developed to solve the mathematical model. To tackle the difficult capacity constraints, we use a penalty function method. Furthermore, a customized heuristics for satisfying the operational requirements is designed as well., Comment: 16 pages, 4 figures and 2 tables

A high-speed train needs high-level maintenance when its accumulated running mileage or time reaches predefined threshold. The date of delivering an Electric Multiple Unit (EMU) train to maintenance ranges within a time window rather than be a fixed date. Obviously, changing the delivering date always means a different impact on the supply of EMU trains and operation cost. Therefore, the delivering plan has the potential to be optimized. This paper formulates the EMU train high-level maintenance planning problem as a non-linear 0-1 programming model. The model aims at minimizing the mileage loss of all EMU trains with the consideration of the maintenance capacity of the workshop and maintenance ratio at different times. The number of trains under maintenance not only depends on the current maintenance plan, but also influenced by the trains whose maintenance time span from the last planning horizon to current horizon. A state function is established to describe whether a train is under maintenance. By using this function the constraint of restricting the total number of trains that are under maintenance can be formulated reasonably well. Finally, a simulated annealing algorithm is proposed for solving the problem., Comment: 15 pages, 5 figures

It is an important objective pursued in a railway agency or company to reduce the major maintenance costs of electric multiple unit (EMU). The EMU major maintenance schedule decides when to undergo major maintenance or undertake transportation task for train-set, based on practical requirements, such as passenger transport demand, workshop inspection capacity, and maintenance requirements. Experienced railway practitioners can generally produce a feasible major maintenance schedule; however, this manual process is time-consuming, and an optimal solution is not guaranteed. This research constructs a time-space network that can display the train-set status transformation process between available and major maintenance status. On this basis, a 0-1 integer programming model is developed to reduce the major maintenance costs with consideration of all necessary regulations and practical constraints. Compared with the manual process, the genetic algorithm with simulated annealing survival mechanism is also developed to improve solution quality and efficiency. It can reduce the complexity of the algorithm substantially by excluding infeasible solutions when constructing the model., Comment: 17 pages, 4 figures

In this paper, we reveal the attenuation mechanism of anchor of the commodity money from the perspective of logistics warehousing costs, and propose a novel Decayed Commodity Money (DCM) for the store of value across time and space. Considering the logistics cost of commodity warehousing by the third financial institution such as London Metal Exchange, we can award the difference between the original and the residual value of the anchor to the financial institution. This type of currency has the characteristic of self-decaying value over time. Therefore DCM has the advantages of both the commodity money which has the function of preserving wealth and credit currency without the logistics cost. In addition, DCM can also avoid the defects that precious metal money is hoarded by market and credit currency often leads to excessive liquidity. DCM is also different from virtual currency, such as bitcoin, which does not have a corresponding commodity anchor. As a conclusion, DCM can provide a new way of storing wealth for nations, corporations and individuals effectively., Comment: 7 pages