Hiroyuki Takanashi

Modeling Infection of Spring Onion by Puccinia allii in Response to Temperature and Leaf Wetness

The influence of temperature and leaf wetness duration on infection of spring onion (Japanese bunching onion) leaves by Puccinia allii was examined in controlled-environment experiments. Leaves of potted spring onion plants (Allium fistulosum cv. Yoshikura) were inoculated with urediniospores and exposed to 6.5, 10, 15, 22, or 27 h of wetness at 5, 10, 15, 20, or 25 degrees C. The lesion that developed increased in density with increasing wetness duration. Relative infection was modeled as a function of both temperature and wetness duration using the modified version of Weibulls cumulative distribution function (R(2) = 0.9369). Infection occurred between 6.5 and 27 h of leaf wetness duration at 10, 15, 20, and 25 degrees C and between 10 and 27 h at 5 degrees C, and increased rapidly between 6.5 and 15 h of wetness at 10, 15, and 20 degrees C. At 25 degrees C, few uredinia developed regardless of the wetness duration. Parameter H, one of eight parameters used in the equation and which controls the asymmetry in the response curve, varied markedly according to the temperature, so that the model could be improved by representing H as a function of wetness duration (R(2) = 0.9501).

System identification of anti-vibration units in semiconductor exposure apparatus

System identification of semiconductor exposure apparatus is discussed. It has a multi-degrees-of-freedom mechanism which includes anti-vibration units for microvibration control. A dynamical model of the mechanism is necessary in order to design the microvibration controller. The model is practically constructed in a short time using a subspace method. Identification results are evaluated through experimental data in comparison with a conventional frequency response method.

Graphical User Interface of System Identification Toolbox for MATLAB

This chapter describes a Graphical User Interface (GUI) of a system identification device used with MATLAB. MATLAB is a well-known software package that is widely used for control system design, signal processing, system identification, etc. However, users who are not familiar with MATLAB commands and system identification theory sometimes find it difficult to use, typically because there are many different approaches to system identification. We propose using a GUI, which is especially suitable for beginners, to provide system identification procedures. The difficulties encountered by beginners in performing system identification might be reduced by using a GUI. The effectiveness of a GUI is illustrated using demonstration data in MATLAB. Modeling of a plant is one of the most important tasks in control system design. There are two main approaches to modeling: white-box modeling based on first principles and black-box modeling based on input and output (I/O) data of a plant. The former is referred to as first principle modeling, while the latter is termed system identification. Computers have become powerful and useful tools in control system design. Several sophisticated software packages (

DEVELOPMENT OF A GUI FOR A SYSTEM IDENTIFICATION DEVICE USING MATLAB

Abstract This paper describes the development of a Graphical User Interface (GUI) for a system identification device using MATLAB. MATLAB is a well-known software package that is widely used for control systems design, signal processing, and system identification. However, beginners who are not familiar with MATLAB commands and system identification procedures sometimes find using it difficult, typically because there exist many different approaches to system identification. We propose the use of a GUI, especially suitable for use by beginners, to provide system identification procedures. Difficulties faced by beginners in the use of system identification might be eased by the use of a GUI. The effectiveness of the GUI is shown by a demonstration data in MATLAB.

System Identification and Physical Parameter Estimation of Anti-Vibration Units in Semiconductor Exposure Apparatus

Abstract In this paper, system identification and physical parameter estimation of semiconductor exposure apparatus for active vibration control are discussed. Since the semiconductor exposure apparatus has multi-degrees-of-freedom (multi-DOF) motional mechanism, the apparatus must be treated as a Multi-Input-Multi-Output (MIMO) system. In this paper, subspace based state-space system identification (4SID) method is applied, because it can be applied to MIMO systems easily. Effectiveness of the 4SID method to an MIMO system identification problem is examined through experimental data. An estimation method of physical parameters of the semiconductor exposure apparatus based on the identified models is also presented. Furthermore, a system identification device is described which is developed for modeling of the semiconductor exposure apparatus. It measures input and output data for identification and executes system identification algorithms based on MATLAB commands.

Development and performance evaluation of portable Braille scanner using simple plate spring sensor

This paper proposes a portable Braille reading sensor which is consisting of three plate springs and strain gauges. A Braille letter is composed of six dots of 3 rows and 2 columns. Each plate spring corresponds to each row of the dot. The detection and conversion process are as follows: With the plate spring passing on a dot, the bending strain of the plate springs are detected through the strain gauge. The detected strain signals are converted to 0-1 normalized sequences, in which 0 means no dot and 1 corresponds to a dot. The three normalized sequences are assigned to 0-1 array of 3 times 2. Further, the array is converted to a corresponding letter, and the sequence of letters is transmitted to the voice signal. The performance of the portable Braille reading system is examined through Braille reading test.

Development of a three-dimensional tactile sensor for minimally invasive instruments

This paper proposes a three-dimensional tactile sensor that can be attached to the tip of an endoscope or catheter to detect the tip contact conditions. Because conventional minimally invasive instruments (MIIs) without a sensor cannot detect the posture and applied force at the tip, operators cannot obtain accurate information during minimally invasive surgery (MIS). The sensor consists of an elastic cylinder and three strain g auges. The gauges, located on the surface of the cylinder at intervals of 120 � , are used to detect deformation of the cylinder caused by contact with the inner walls of the patients organs. The output voltage signals of the gauges are approximated by a sinusoidal function with a phase difference of 120 � . The three-dimensional contact angle and applied force at the tip of the sensor can be estimated accurately from the three sinusoidal functions and measured output voltage signal from the gauges. The operating principle of the sensor is examined through several experimental conditions. To improve the effectiveness of minimally invasive surgery (MIS), it is necessary to develop better endoscope and catheter techniques. Conventional minimally invasive instruments (MIIs) improve the quality of life (QOL) of patients, because they can begin rehabilitation only a few days after MIS. However, the manipulation of MIIs is difficult because opera tors cannot obtain accurate information about the tip contact conditions of MIIs with the walls of the patients organs. In conventional MIS, the operator manipulates the MII based on both the tactile sensations transmitted to their hand via the MII and the two-dimensional X-ray image information. However, tactile sensations are a mixture of the contact and friction forces with the walls of organs, and it is difficult to discriminate these forces precisely. Therefore, operators need to be highly trained; a lack of this skill on their part may lead to critical accidents. The abovementioned issues have necessitated the development of mechanisms for detecting the posture of the MII tip. Some active devices (1-4) have been developed to help manipulate catheters (3) and endoscopes (4). In these devices, shape memory alloys (SMAs) are used as actuators. In addition, inchworm locomotion (5) has been developed. An inchworm-like robot with a bellows mechanism

Prediction of Disease Infection of Welsh Onions by Rust Fungus Based on Temperature and Wetness Duration

The style of agriculture practiced in Japan and other countries in Asia is small scale compared to that in North America. While systematic production and management systems have been maintained in Europe and America, Japanese agricultural style tends to depend on past experiences, and application of agricultural chemicals is guided by the calendar and past experiences. Japan is also advanced in the field of plant disease prediction. This paper focuses on a prediction model of disease infection for a foliar parasite on Welsh onions. Rust fungus disease is the most typical disease on Welsh onions, and the Weibull probability density function is appropriate for approximating the infection rate of the disease. The model utilizes temperature and wetness duration to predict the infection of Welsh onions by rust fungus. Producers, then, can use the model to determine the day on which the infection rate will rapidly increase, then carry out appropriate countermeasures to the disease. The proposed prediction method is applicable to several infections found throughout Asia.