Train timetable evaluation from the viewpoint of passengers by microsimulation of train operation and passenger flow

In order to evaluate train timetables from point of view of the passengers, it is indispensable to estimate the disutility of passengers. This can be done by accurately estimating the movements of passengers and trains. In particular, when there is a large number of passengers, the interactions between the passengers and trains must be considered. To this end, we have developed a microsimulation system to simulate both train operation and passengers' train choice behavior. The system can simulate the train choice behaviors of more than one million passengers as well as their positions in trains. It is possible to estimate the delays caused by crowding in trains as well. The system is based on models of different attitudes of the passengers with respect to the train choice behavior, which includes the choice of the earliest train, transfer avoidance, and avoiding crowding; a passenger's train choice behavior reflects his/her preferences. We applied this system to an actual railway line in a metropolitan area and evaluated two train schedules by calculating the generalized cost, which reflects each passenger's disutility based on his/her experience. Numerical experiments confirmed that the proposed method is very useful for evaluating timetables from the point of view of the passengers. © 2012 Wiley Periodicals, Inc. Electr Eng Jpn, 181(4): 51–62, 2012; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.21264     

Color Specification for Structural Colors by Using Reflection Spectrum

In this paper, color specification procedure for structural colors by using reflection spectrum in visible wavelength is proposed. The tristimulus values in XYZ color system are obtained from the reflection spectrum calculated by transmission-line theory, and transformed into tristimulus values in standard red-green-blue (sRGB) color system. By using the sRGB, structural color is quantitatively specified. From some numerical results, it is shown that our suggested color specification procedure is valid. Copyright © 2009 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Improvement of Abnormality Detection System for Bathers Using Ultrasonic Sensors

This paper proposes a new method for improving an existing abnormality detection system for a person who soaks in a bathtub. As the number of aged people increases year by year in Japan, bathing accidents among the aged are growing at a rapid rate, especially in‐bathtub drowning accidents. Therefore, prompt detection of a bather's abnormality, such as dizziness and fainting, is important to prevent in‐bathtub drowning. In order to detect a bather's abnormality promptly, an abnormality detection system using seven ultrasonic sensors has been proposed. The system uses two methods—posture detection and motion detection—to detect a difference in a bather's state compared to normal before an accident occurs, and improves the delay in detection considered heretofore to be a serious problem. There was, however, plenty of room for improvement. In order to improve the detection rate of the system, we propose a new detection method in this paper. The method uses two ultrasonic sensors to scan a bather's head and neck, and detects the head height and swing speed of the head. Experimental results are superior to the accuracy of the existing system, which enables us to detect an abnormality in a bather more precisely. © 2012 Wiley Periodicals, Inc. Electr Eng Jpn, 179(3): 57–67, 2012; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21133     

Controller-Switching Strategy for HDD Servo Systems with Measurement Errors and Constraints on State and Control Variables

The head-positioning control system of a hard disk drive (HDD) must enable precise positioning and high-speed access. Mode switching control (MSC) has widely been used to meet these control requirements. One of the issues with MSC is how to determine the controller-switching strategy, which needs decisions on the controller's switching conditions and its initialization. We propose a method that utilizes initial value compensation (IVC) to determine the initial state of the controller. Although mode switching is non-linear, transient responses can be improved if the control system takes the initial state response after mode switching into consideration. IVC, which is based on this, can improve the transient response after mode switching. We also propose a method, which is based on the concept of a maximal output admissible set, of determining the switching conditions. It takes pointwise-in-time constraints and measurement errors in the plant's initial state into consideration. Experimental evaluations of the switching-control strategy we propose were undertaken with a 2.5-inch form-factor HDD. Copyright © 2009 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Information system development by business process modeling based on adaptability to specification changes

Business modeling has been attracting attention in the development of information systems to be used for analyzing and designing the working procedures of the system under development. In this paper, we propose a method of information system development by business process modeling based on adaptability to specification changes. The proposed method builds a business process model from the requirement specifications, translates the model into UML, identifies the elements bridging the translation from Business Process Modeling to UML, that is, the analytical stage and the design stage, and seeks to perform both processes continuously while finalizing the design. The proposed method was applied to the prototyping of a bus booking and management system, comparing the results using only UML for the configuration with those obtained by using the proposed method. The proposed method proved effective in the early detection and removal of bottlenecks, in accurate modeling, and in adjusting to changes in the specifications. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 174(2): 54–64, 2011; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21045     

A new command governor architecture for transient response shaping

In this paper, we develop a control framework for stabilization and command following of nonlinear uncertain dynamical systems. The proposed methodology consists of a new command governor architecture and an adaptive controller. The command governor is a dynamical system that adjusts the trajectory of a given command to follow an ideal reference system capturing a desired closed‐loop dynamical system behavior in transient time. Specifically, we show that the controlled nonlinear uncertain dynamical system can approach the ideal reference system by choosing the design parameter of the command governor. In addition, an adaptive element is used to asymptotically assure that the error between the controlled nonlinear uncertain dynamical system and the ideal reference system is reduced in long term. Therefore, the proposed methodology not only has closed‐loop transient and steady‐state performance guarantees but can also shape the transient response by adjusting the trajectory of the given command with the command governor. We highlight that there exists a trade‐off between the adaptive controller's learning rate and the command governor's design parameter. This key feature of our framework allows rapid suppression of system uncertainties without resorting to a high learning rate in the adaptive controller. Furthermore, we discuss the robustness properties of the proposed approach with respect to high‐frequency dynamical system content such as measurement noise and ∕ or unmodeled dynamics. A numerical example is provided to demonstrate the efficacy of the proposed architecture. Copyright © 2012 John Wiley & Sons, Ltd.     

Nondaily behavior detection monitoring system for elderly people based on bayesian network representation of omnidirectional vision sensor

This paper describes an unusual behavior detection system based on an omnidirectional vision sensor, as one of the important elements in realizing “Sensing and Robotic Support Rooms” for elderly people. Such support rooms are expected to be further developed in the future with advanced abilities to automatically recognize elderly people's actions and behavior patterns, to detect unusual patterns by using sensors, and to support their daily motions by using robotic manipulator control systems. The proposed monitoring system using an omnidirectional vision sensor automatically learns daily behavior patterns and detects unusual behavior patterns and actions by using the Bayesian network approach. The Bayesian network is constructed by using image feature values such as area and center‐of‐gravity values extracted from a captured image sequence, and the respective behavior patterns are represented as conditional probabilities. Unusual behavior patterns can be automatically detected on the basis of the low generation probability values. Experiments based on the investigation of elderly people's typical daily behavior patterns have shown the effectiveness of the proposed system. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 172(3): 42–51, 2010; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20990     

基于帧间差和肤色特征人脸检测与跟踪算法

在类似于电视会议这样的应用中，实现人脸的准确检测及跟踪是关键的任务。在文中，我们提出一种人脸检测和跟踪算法，本算法基于帧间差和肤色特征。实验结果表明，文中提出的方法能够在复杂背景下有效地实现人脸的检测和跟踪。     

Contributions of generators for power flow and loads in a power system

Because of the introduction of deregulation and competition in the electricity supply industry, large numbers of IPPs (Independent Power Producers) will get into the market. It has become much more important to be able to determine which generators are supplying a particular load, which generator is responsible for transmission line congestion, and what is each generator's contribution to the system losses. In this paper, we propose a way to calculate these contributions automatically. The applicability of the proposed technique is demonstrated using the EAST 10 47‐bus power system. © 2003 Wiley Periodicals, Inc. Electr Eng Jpn, 144(3): 28–35, 2003; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10181     

Partial discharge recognition system for current transformer using neural network and 2D wavelet transform

In this paper, a neural network and two‐dimensional (2D) wavelet transform are applied to recognize partial discharge (PD) patterns on current transformers (CTs). To avoid the discrepancy between simulated results and real experimental data, we adopted seven cast‐resin CTs that were purposely fabricated with various insulation defects as the PD patterns collected samples to actually emulate the various defects incurred often during their production. All measurements are taken in a shielded lab; the commercial TE571 PD detector is adopted to measure PD patterns to ensure the reliability of the PD signals. Next, we extract the patterns' features via a 2D wavelet transform and use the features as the training set of a backpropagation neural network (BNN) to construct the recognition system for CTs' PD patterns. Finally, we add random noises to the measured PD signals to emulate the field diagnosis under a high‐noise environment. The study results indicate that, under a simulated noise magnitude of 30 pC, the recognition rate of the proposed system still can reach around 80%, signifying a great potential in applying the proposed recognition system in field measurements in the future. © 2011 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Automatic driving system using identification of switched systems with unknown switch points

In this paper, we propose a modeling method for evaluating drivers' driving skill, with which automatic driving of a vehicle is realized. The method is to formulate the automatic driving system of a vehicle as a switched system with unknown switch points by using the hinging hyperplane auto regressive eXternal (HHARX) model, which can extract driving operation modes and their switch conditions simultaneously. To verify the effectiveness, we apply the proposed method to an automatic driving system of a small remote‐controlled vehicle, instead of a real vehicle. Simulation results illustrate that the obtained models can achieve functions such as start acceleration, normal traveling, stop deceleration and auto steering in the automatic driving system. © 2006 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Robust damping control of power oscillation incorporating parametric resonance

In this paper we consider a damping control of low‐frequency oscillations in an electric power system. On the basis of the hypothesis that an auto‐parametric resonance model can explain a power oscillation, we propose a new model for a robust damping control, by which the system maintains stability even if some auto‐parametric resonance happens. With this model, we can express a parametric variation of a principal oscillation mode and a class of uncertainties which cover neglected dynamics. Since the model has a certain structure of uncertain parameters, we design a robust controller via µ‐synthesis. The robust controller which can be obtained from the presented design strategy has the property that the control performances are more sophisticated in comparison to controllers designed with other existing methods based on the H_∞ control. © 2002 Wiley Periodicals, Inc. Electr Eng Jpn, 142(1): 42–49, 2003; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10069     

Design Estimation of the Hybrid Power Source Railway Vehicle based on the Multiobjective Optimization by the Dynamic Programming

The power source of hybrid railway vehicles consists of both generation and energy storage devices. The hybrid vehicles have a high degree of freedom in the system design because they have different power sources. Therefore, it is difficult to establish generalized design methods of the power system. Various patterns of device capacities of generation and energy storage equipments are available for the hybrid vehicle. And various types of power control strategies are also selectable. With this background, this paper proposes a globally searched design estimation method for hybrid vehicles, which is based on multiobjective optimization by dynamic programming. The proposed method enables us to globally clarify the optimal candidates in accordance with various railway lines from a wide search domain. This results in various design concepts of the hybrid vehicles. Then, this paper confirms that the proposed method provides effective design guidelines for the conceptual design of the hybrid vehicles. Therefore the proposed method is useful for the design problem of hybrid vehicles that have a higher degree of freedom compared to electric railway vehicles. Copyright © 2007 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Dynamic optimal route search algorithm for car navigation systems with preferences by dynamic programming

Optimal route search to the destination is one of the most important functions of car navigation devices. The development of road traffic infrastructure has made it possible to receive real‐time information of the traffic situation. Route search algorithms for car navigation devices make use of this information to avoid the traffic congestions. Such algorithms should find the new optimal route efficiently when the traffic situation changes. Usually, the minimum traveling time or distance is considered to define the optimal route. However, the minimum traveling time or distance is not always what the user is looking for. The user may prefer to travel on a certain route even at the cost of traveling time or distance. Car navigation devices should consider such preferences when finding the optimal route. In this paper, we propose a dynamic programming algorithm to find the optimal route considering that it should deal with the changes of the traffic situation and multiple criteria. The proposed method uses the information from the previous computation to find the new optimal route considering user preferences when the traveling time of the road section changes. The proposed method was applied to a real road network to find the optimal route. Results show that the proposed method can find the user‐preferred optimal route. Simulation results also show better calculation time of the proposed method compared to the Dijkstra algorithm. Copyright © 2010 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

关于城市照明色彩体系规划与设计的研究

城市照明建设中要创造独具特色的城市夜景观,就需要在色彩体系规划与设计上遵循其自身的科学规律,即遵守一定的规律与原则。本文依据目前城市使用主流光源的现状给出了城市照明色彩体系规划与设计中各种情况下应使用的光色的定量范围,并提出了在此原则基础上城市照明色彩体系规划与设计的一些方式方法。     

Integrated reproduction of human motion components by motion copying system

Currently, the development of leading‐edge technology for recording and loading human motion on the basis of haptic information is required in the fields of manufacturing and human support. Human movement is an assembly of motion components. Since human movements should be supported by a robot in real time, it is necessary to integrate the motion components that were saved earlier. Once such motion integration is realized, future technology for use in daily human life can be developed. This paper proposes the integrated reproduction of the decomposed components of human motion by using a motion copying system. This system is the key technology for the realization of the acquisition, saving, and reproduction of real‐world haptic information. By using the proposed method, it is possible not only to achieve expert skill acquisition, skill transfer to robots, and power assist for each motion component, but also to open up new areas of applications. © 2012 Wiley Periodicals, Inc. Electr Eng Jpn, 181(1): 28–35, 2012; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.21263     

Identification of task model using piecewise affine systems with variable switching points and its application

This paper considers a human‐operated task model based on identification techniques using switched systems expressed by mixed logical dynamical systems. In the system, each subsystem is expressed by a piecewise affine system. For a model to be identified, it is not easy to determine a number of subsystems in advance. In this paper, we propose a simultaneous identification technique which takes into account both a number of subsystems and parameters, so that a piecewise affine model of a human operation can be obtained. In addition, the obtained model is applied to automation. The effectiveness of the proposed method is illustrated by simulations and experiments. © 2011 Wiley Periodicals, Inc. Electr Eng Jpn, 176(1): 46–54, 2011; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21079     

Route guidance by a car navigation system based on augmented reality

Car navigation systems play a prominent role in road traffic safety and traffic regulation. However, it is necessary to improve the route guidance of car navigation systems so that they accurately and quickly recognize small differences in location. Thus, to increase the ease of understanding and safety of car navigation systems, navigation systems based on augmented reality have been proposed for providing guidance at road intersections. We are currently developing a car navigation system based on augmented reality, called AR‐Navi. We investigated designs for the display of road intersection guidance that can be easily understood even when limited information is available and proposed a “best shot” display method that does not use moving images. In addition, we implemented a prototype system that includes these methods and conducted driving experiments on public roads to evaluate the ease of understanding and safety of AR‐Navi. Using the evaluation results, we confirmed that the ease of understanding and safety is similar in the case of AR‐Navi and CG‐Navi. We also clarified the characteristics of AR‐Navi. © 2012 Wiley Periodicals, Inc. Electr Eng Jpn, 180(2): 43–54, 2012; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.22278     

Estimation of traffic congestion distance using frequency division multiplexing based on IEEE802.15.4

We propose a system to estimate the traffic congestion distance using IEEE 802.15.4, that is extended by multicommunication frequency division multiplexing. Our proposed system is developed at 20% equipped rate, where five lanes are considered. Furthermore, in our proposed system, it is assumed that the equipped rate in all lanes increases. Our proposed method can estimate an error rate lower than 10% approximately at on equipped rate greater than 50%. Additionally, we use 16 terminals in the actual environment. From the actual experiment, we find that our proposed method involving the use of communication pattern 2 is 300% faster than the existing method. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.