In response to aging societies around the world, there is an increasing need to develop and design equipment oriented towards elderly users. However, in the field of IT equipment, consideration of the cognitive characteristics of elderly users is still insufficient. In order to design equipment that is elderly-friendly, it is essential to develop clear design principles based not only on perceptual and physio-motor characteristics, but also on the cognitive characteristics of older adults. In this paper, a usability test was applied to automatic teller machines (ATMs), a typical example of IT equipment that is not elderly-friendly. Through analyzing the interaction between the elderly and ATMs, some cognitive and behavioral characteristics of older adults were extracted. Based on these cognitive/behavioral characteristics and principles for healthy aging, new guidelines (design principles) were created recommended for use when developing elderly-friendly IT equipment.

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We consider a class of delivery services, in which products are delivered to customers under the following two conditions: 1) each supplier must offer its own uniform price to all customers regardless of possibly different transportation costs; 2) each supplier offers its delivery service to a customer only when it results in a positive return. A competitive market of this sort with two suppliers and two (grouped) customers is formulated as a symmetric two person game. With a set of mixed strategies defined on a certain set of L discrete points, it is shown that two types of Nash equilibriums exist and can be constructed explicitly. Furthermore, such Nash equilibriums converge to the mixed strategies defined on a continuum, which are also Nash equilibriums, as L→∞.

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Touch panels have applications in a wide range of situations. For example, they are used in ticket-vending machines at stations, automated teller machines at banks, and in the medical field. Owing to this widespread use, much research regarding touch panel operability has been done. Accordingly, the interface design of touch panels has improved. However, there has been no research focusing on how covering the display with hand can affect touch panel operability. In this study, we conducted one experiment to evaluate the effect on touch panel operability when the hand covers part of the display. In addition, we measured maximum torque ratio of the upper arm to evaluate arm load during touch panel operation. In this experiment, ten healthy male subjects were asked to operate touch panels under three touch-panel angle conditions: 0, 45 and 90 degrees. We also measured the area on the display covered by the hand, switch pointing time, the subjects' complaint of visibility of the display and maximum torque ratio of each joint as evaluation indexes. The results showed that touch-panel angle has an influence on the range and position of the area that the hand covered. Additionally, switch pointing time and the subjects' complaint of visibility both became worse when the display was covered with the hand. Moreover, we found that the value of the maximum torque ratio of the upper arm decreased when the touch-panel angle was 90 degrees.

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In Japan, in view of the aging society, there is a strong need for the development of IT equipment that is elderly-friendly. Above all, this applies to public IT equipment for financial institutions, such as ATMs, which are essential for banking business since they are vital to a new type of customer service, namely unattended branch offices. In this study, a new ATM with an interface suited to elderly users was designed using proposed design principles based on the cognitive behavioral characteristics of elderly people. The effectiveness of the new ATM design and the design principles was examined by comparing it with a conventional ATM. Experimental results show a lower number of operational troubles and errors, and shorter operation time compared to the conventional ATM. Therefore, the effectiveness of the proposed principles was confirmed. Furthermore, a model for procedures to design interactive equipment aimed at elderly users was suggested.

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In traditional reliability theory, both the system and its components are allowed to take only two possible states: working or failed. On the other hand, in a multi-state system, both the system and the components are allowed to be in M+1 states, i.e., 0, 1, 2,…, M. A multi-state system reliability model provides more flexibility for the modeling of equipment conditions. In this paper, we provide a new recursive algorithm for evaluating the system state distributions of generalized multi-state k-out-of-n:F systems. This recursive algorithm is useful for any multi-state k-out-of-n:F system, including the decreasing, increasing and non-monotonic types of multi-state k-out-of-n:F systems. We calculate and compare the orders of computing time and memory capacity of our algorithm with existing algorithms.

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A series-parallel system is one of the most popular redundant system models. It consists of subsystems that are connected in series and each subsystem consists of interchangeable components in parallel. There are two types of such systems: all components can work for all subsystems, or the components consisting of a certain subsystem can work only in that specific subsystem. For the first case, there are some heuristic methods to approximately solve the optimal component allocation. Yamachi et al. [9,10] proposed an algorithm that obtains the exact Pareto solutions for problems that are not so large, and a solution method that obtains approximate solutions for large problems. The method was based on an evolutional algorithm. For the second case, Yamachi et al. [13] proposed the depth first search (DFS) algorithm that obtains exact Pareto solutions using the branch and bound method. The method is made for a series k-out-of-n system, which is a system consisting of k-out-of-N subsystems that are connected in series. In this paper, we propose an alternate method for the second case; a new algorithm that employs the breadth first search (BFS) method to find Pareto solutions for a series k-out-of-n system more efficiently than the existing algorithm.

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This study is concerned with the single-machine scheduling problem for jobs with a common due date. A penalty is incurred to the jobs completed before or after the given due date, and the minimization of the weighted sum of penalties is the primary objective for the problem. This study further assumes that the processing time of jobs is uncertain, but their maximum and minimum processing times are deterministic and known in advance. A combination of actual processing time of jobs constitutes a scenario, and a robust schedule of which worst-case performance is best under the set of all candidate scenarios is presented. For 210 problem instances with seven jobs, robust schedules were obtained and then evaluated under four reduced sets of scenarios in the numerical experiment. The results revealed that the robust schedules initially obtained often produced good results under the reduced sets of scenarios. From the viewpoint of best worst-case performance, obtaining a robust schedule that considers all potential scenarios is shown to be beneficial even if some scenarios rarely happen and are negligible.

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This paper discusses the use of cutting-edge energy devices, such as high-capacity lithium-ion batteries, in office building energy management systems. We simulate an energy management system using a time-marching method and an energy network based on discrete models. The simulation enables not only operating costs but also CO_2 emissions of devices to be seen. As a result, installation of new energy devices can be assessed based on initial investment, operating costs and CO_2 emissions. Additionally, we provide examples of optimized operation and installation of new energy devices.

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