Motohiro Ohkura

When calculating the fare between a given pair of stations, the minimum cost path from among the many feasible paths between the stations must be determined. The railway fare for a specific path is usually calculated by distance, i.e. the longer the distance, the higher the fare. The fare rate, however, differs between railway companies and there are additional rules to be used in the fare calculation, e.g. discounts for specific paths. Therefore, the shortest-distance path is not always the minimum cost path. Most previous research efforts have focused on the enumeration of feasible paths between a pair of stations and a comparison of their resulting fares in order to choose the minimum fare for the pair. Using this approach, computational time is inevitably long. In this paper, we propose some network representations for the fare calculation of a railway network and use an efficient algorithm based on Dijkstra's algorithm to calculate fares between all pairs of 1638 stations in the area where IC-ticket (Suica/Pasmo) is usable. Our algorithm reduces the computational time because the algorithm need not enumerate a large number of paths for every pair of stations.

We propose an algorithm to find the lowest-fare path between two specified stations in the JR-EAST area where the IC-card ticket will be available in 2007. The lowest-fare path is sometimes different from the shortest path, because JR-EAST has many exceptional calculation rules in addition to the four calculation-tables used for the three specified areas and two kinds of lines, i.e. the main line and local line. Our algorithm solves at most only four shortest path problems for the fare between two specified stations, although it can deal with the complex situation mentioned above. Therefore the algorithm can calculate fares between all pairs of stations not only very quickly but also exactly.

We discuss the network representation method for calculating railway fares. The railway system has a typical network structure consisting of stations as nodes and railbeds as arcs. When we, however, try to represent junctions on the network, we encounter some problems. For example, there are several complex junctions that cannot be represented by integrating nodes associated with the junction or introducing dummy arcs with a distance of zero for a connection node on foot. We show an idea for network representation in order to apply algorithms to the shortest path problem, which is the basis for calculating railway fares. Our surrogate network finds the shortest path between two specified stations exactly.

The basic difficulties with nurse scheduling lie in the necessity of maintaining a certain level of service and skill in the makeup of every shift, while balancing the workload among the nurses involved. This is usually prepared on paper by a head/chief nurse and takes a considerable amount of time and effort.<br>In order to lighten the burden we are aiming to developing an efficient support system that enables a head/chief nurse to concentrate her thoughts on scheduling without needing a prior knowledge of computer operation. In our previous study, task analysis of manual nurse scheduling was performed. The result of the analysis led to the following four user-interface functions that would be needed in a support system; (1) A tool that supports eyes' moving over a spreadsheet, (2) A tool that highlights each nurse and each day that need looking at again, (3) A warning message for a lack of nurses working a night shift, (4) An efficient input tool for marking the cells. Furthermore, in this paper, we divided the scheduler's tasks into those which could be performed by only a computer and those which need a human to complete. We then created an interface based on the above.<br>Five head nurses were given a hands-on demonstration of the support system including the interface. In addition, a chief nurse actually made a monthly schedule using the support system. All six nurses were impressed with its effectiveness and expressed that they wanted to use this system every month, especially the chief nurse.

The basic difficulties with nurse scheduling lie in the necessity of maintaining a certain level of service and skill in the makeup of every shift, while balancing the workload among the nurses involved. This is usually prepared on paper by a head/chief nurse and takes a considerable amount of time and effort.<br>In order to lighten the burden we are aiming to developing an efficient support system that enables a head/chief nurse to concentrate her thoughts on scheduling without needing a prior knowledge of computer operation. In our previous study, task analysis of manual nurse scheduling was performed. The result of the analysis led to the following four user-interface functions that would be needed in a support system; (1) A tool that supports eyes' moving over a spreadsheet, (2) A tool that highlights each nurse and each day that need looking at again, (3) A warning message for a lack of nurses working a night shift, (4) An efficient input tool for marking the cells. Furthermore, in this paper, we divided the scheduler's tasks into those which could be performed by only a computer and those which need a human to complete. We then created an interface based on the above.<br>Five head nurses were given a hands-on demonstration of the support system including the interface. In addition, a chief nurse actually made a monthly schedule using the support system. All six nurses were impressed with its effectiveness and expressed that they wanted to use this system every month, especially the chief nurse.

A reading system was developed to aid adventitiously blind people in reading and writing English documents by themselves. The system is made up of three subsystems, i.e. pattern recognition, construction of character data base and speech output. This system has following features.<br>(1) Verbal guidance and confirmation are provided to enable blind users to operate the system by themselves.<br>(2) The users can build their own personal reading system by recording features of fonts through the subsystem of constructing character data base, though the help from the sighted is essential in this process.<br>(3) Since a simple editing function is embeded in the system, it can be used as a typewriter, as well as a text reversion system.<br>An evaluation of the system was made by a blind person, and a good result was obtained in his overall acceptance of the system.