We have first attempted to develop high performance and safe fuel cells using ammonium formate as solid (powder) fuel. This solid fuel has potential to realize safe portability compared with liquid fuel such as methanol from the viewpoint of toxicity and flammability. In order to make use of some advantages of ammonium formate, we have investigated oxidation characteristics of ammonium formate toward Pt electrode. From cyclic voltammograms, ammonium formate has high activity to be oxidized with a Pt electrode. We have found that oxidation of ammonium formate can be improved by additional Ir catalysts with Pt catalysts. There is a high potentiality that ammonium formate is useful as solid (powder) fuel for polymer electrolyte membrane (PEM) fuel cells. This new fuel will be driving force to develop safe fuel cells for PEM.

抄録全体を表示

An integrating sphere is used to measure spectral distribution, calculate total luminous flux and calculate chromaticity coordinates of LEDs. It usually has to consider self-absorption when light source is radiating in the integrating sphere. The LED with coloured parts, such as printed circuit board, heat sink and so on, should be careful in particular. In case of the large enough sphere, self-absorption spectrum of LED has almost flat spectral distribution and its absorption level is few. Hence, the calculated total luminous flux and chromaticity coordinates of LED are almost same, even if self-absorption correction is applied or not. In the small sphere case, self-absorption of LED has spectral distribution with coloured piece and is given some influence. The correction spectrum can be measured individually in each color peace with an auxiliary lamp set up in the integrating sphere. After having spectral correction, total luminous flux comes close to large sphere case and chromaticity coordinates accord with large sphere case.

抄録全体を表示

In a wireless LAN, since two or more terminals in a service area do the random access in a signal channel, it is necessary to achieve an efficient access that reduces the frame collision. Under the standard IEEE 802.11 protocol, each terminal sets a random backoff. Collision avoidance are being achieved while it generates useless standby time and acheives low throughput. To solve that problem, this paper proposes a channel access method which fixed backoff after success transmission. Via simulation, the proposed method reduces frame collisions and improves throughput . Furthermore, our method provides less frame loss probability and smaller file transfer delay.

抄録全体を表示

The electrocardiogram (ECG) provides important information about hear rate and autonomic activity. This report describes a nonrestrictive ECG method using a neckband to position activity. This report describes a nonrestrictive ECG method using a neckband to position activity electrodes on the skin of the neck. The system consists of a dry-type activity electrode, an instrumentation circuit, and a neckband. The dry-type activity electrode is connected to the instrumentation circuit with high input impedance in order to prevent noise contamination. Moreover, this method avoids skin rash since it does not use paste to reduce the impedance between the skin and the electrode.
ECG measurement was performed simultaneously using the conventional limb lead method and the neckband system. ECG measurement was performed for about 8 seconds at rest in each of five healthy adults. Timing of ECG R wave peaks was compared between the two methods, and the difference was found to be less than 3.6 ms. Furthermore, the neckband system was able to detect ECG R waves while walking.
These results show that the neckband system is useful and suggest that it may be appropriate for measuring ECG R waves during activities of daily living.

抄録全体を表示

Business modeling in recent years, has attracted attention in the development of information systems for analyzing and designing the working procedures of the system under development. In this paper, we propose an information system development method by business process modeling based on adaptability for specification changes. The proposed method builds a business process model from the requirement specifications, translates the model into UML, clarifies the elements bridging the translation from Business Process Modeling to UML, in other words the analytical stage and the design stage, and seeks to perform both processes continuously in 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 using the proposed method. The proposed method proved effective in the early detection and removal of bottlenecks, in accurate modeling, and in coping with changes in the specifications.

抄録全体を表示

This paper explores the active and reactive power sharing scheme for the parallel operation of inverter interfaced distributed generators (DGs) in a microgrid system. Applicability of conventional wireless control technique, based on P-f and Q-V droop regulations, is also investigated for the load sharing among the DGs with the help of small signal analysis. The conventional droop technique is found to be ineffective in a distribution system with resistive dominated line. In particular, the reactive power becomes highly uncontrolled with large circulating VAR in the presence of high R/X. The virtual impedance concept proposed in the paper intends to address this problem. The so-called virtual impedance is self-regulated variable aiming to reduce the impedance mismatch thereby eliminating the circulating VAR. Consequently, the scheme provides effective active and reactive power sharing among the DGs by adjusting the magnitude and frequency of the voltage at steady-state. Simulation results presented for the two-DGs microgrid system, confirms the validity of the proposed scheme.

抄録全体を表示

General anesthesia used for surgical operations may cause unstable conditions of the patients after the operations, which could lead to respiratory arrests. Under such circumstances, nurses could fail in finding the change of the conditions, and other malpractices could also occur. It is highly possible that such malpractices may occur while transferring a patient from ICU to the room using a stretcher. Monitoring the change in the blood oxygen saturation concentration and other vital signs to detect a respiratory arrest is not easy when transferring a patient on a stretcher. Here we present several noise reduction system and algorithm to detect respiratory arrests in transferring a patient, based on the unconstrained air pressure method that the authors presented previously. As the result, when the acceleration level of the stretcher noise was 0.5G, the respiratory arrest detection ratio using this novel method was 65%, while that with the conventional method was 0%.

抄録全体を表示

We have developed a behavior detection system using a neural network (NN). The system detects dangerous behaviors that are almost falling from a bed and having fallen from the bed. The system uses captured pictures with a WEB camera for detection. The system classifies their behavior into five states using the NN. Five states are lying in the bed, being sitting up in the bed, sitting in the bed, almost falling from the bed and having fallen from the bed. Then, we define almost falling and having fallen from the bed as dangerous behavior. Moreover, we define lying in the bed, being sitting up in the bed, sitting in the bed as safety behavior. We proposed a final detection rule by which the system classifies their behavior into two states. Finally, a detection ability of the system is evaluated. From the experiment results, the detection rate of dangerous behavior is shown 81.7% using the proposed system.

抄録全体を表示

A design of model following control system(MFCS) for linear neutral system with time delays and disturbances is discussed. It was proposed by S. Okubo^(1)∼(5) for a family of plants in previous studies. In this paper, the method of MFCS will be extended to linear neutral system with time delays. In this case, this method has verified by a numerical example and simulations.

抄録全体を表示

In this paper, the extended division algorithm for polynomial matrices will be revised. The revised version of algorithm does not depend on the controllability canonical realization of the transfer function matrix, which will be obtained from a given polynomial matrix pair. Using the new version, a calculation of stabilizing controllers corresponding to the design in state space will be presented.

抄録全体を表示

There are a lot of multi-inputs multi-outputs (MIMO) systems in the chemical plants of the manufacturing, and they have the multiple time delays which are different length in each their inputs and outputs pair. This paper explains two-degreeds-of-freedom (2DOF) control system based on generalized minimum variance control (GMVC) for MIMO systems. It can improve the tracking performance to the reference signals and the response property for the disturbance. And the states between the sampling period can be expressed by using the modified z transform for considering multiple time delays. Additionally Tracking Controller is designed to decoupling plant.

抄録全体を表示

A communication aid with human eyes only is proposed. A set of candidate character is displayed onto computer screen of relatively small and light Head Mount Display: HMD that is mounted on glasses of which user wears on. When user looks at a candidate character with his/hers left eye while right eye picture is taken with small and light web camera that also is mounted on the glasses. The proposed system can selects 81 characters with two layers of 9 by 9 character candidate image. Other than these there is another selective image including control keys and frequently use of sentences. By using image matching between previously acquired template image for each candidate character and the currently acquired image, the proposed system realizes that which character in the candidates is selected. By using blinking and fix one's eye on combine together, the proposed system recognizes that user determines the selected key from the candidates. The blinking detection method employs a morphologic filter to avoid misunderstanding of dark eye detection due to eyebrows and shadows. Thus user can input sentences. User also may edit the sentences and then the sentences are read with Text to Speech: TTS software tool. Thus the system allows support conversations between handicapped and disabled persons without voice and the others peoples because only the function required for conversation is human eyes. Also the proposed system can be used as an input system for wearable computing systems. Test results by the 6 different able persons show that the proposed system does work with acceptable speed, around 1.5 second / character.

抄録全体を表示

We developed a computer-aided diagnostic (CAD) scheme for detection of subtle image findings of acute cerebral infarction in brain computed tomography (CT) by using a contralateral subtraction technique. In our computerized scheme, the lateral inclination of image was first corrected automatically by rotating and shifting. The contralateral subtraction image was then derived by subtraction of reversed image from original image. Initial candidates for acute cerebral infarctions were identified using the multiple-thresholding and image filtering techniques. As the 1st step for removing false positive candidates, fourteen image features were extracted in each of the initial candidates. Halfway candidates were detected by applying the rule-based test with these image features. At the 2nd step, five image features were extracted using the overlapping scale with halfway candidates in interest slice and upper/lower slice image. Finally, acute cerebral infarction candidates were detected by applying the rule-based test with five image features. The sensitivity in the detection for 74 training cases was 97.4% with 3.7 false positives per image. The performance of CAD scheme for 44 testing cases had an approximate result to training cases. Our CAD scheme using the contralateral subtraction technique can reveal suspected image findings of acute cerebral infarctions in CT images.

抄録全体を表示

Differential Evolution(DE) is one of the evolutionary algorithms, and has shown excellent ability for solving global optimization problems over continuous spaces. DE has a few control parameters that have to be set by users. The ability of DE is depending on these control parameters, and, in many cases, trial-and-error process are required for finding suitable parameters. This paper proposes a method for tuning the DE control parameters automatically. The proposed method tunes control parameters within DE search process. By using this method, trial-and-error processes for finding appropriate control parameters are not required. To evaluate the performance, the proposed method was applied to 9 benchmark function optimization problems. The results indicate that the proposed method shows 100% feasibility to solving the optimization problems without outstanding increase of generations required for finding the optimum solutions.

抄録全体を表示

Robustness of the 19-inch racks are tested when strong artificial vibrations are added them. We have confirmed that four kinds of rack we chose have rigidity up to 300gal to ground level accelerated velocity by itself. Also it shows the same result that the network devices installed in the rack-mounted way or tightened with surface fastener. It means that 19-inch racks and the network devices work properly during adding the vibration. We have confirmed four kinds of different way of installation of the network devices in the rack; it turns out to be the figure of each accelerating dynamic magnification has little practical difference.

抄録全体を表示

In this paper, we describe a new digital watermarking method for embedding a binary watermark based on fractal image coding. This technique can embed four bits or less into a range block by controlling the domain block address information composed of 16 domain block groups. Since the watermark is embedded in order of a high variance value block from among all range blocks, the accuracy of the watermark detection is improved. The performance of the proposed watermarking for the PSNR of watermarked images and the robustness for JPEG compression is shown.

抄録全体を表示

This paper proposes a method for detecting remaining files copied from removable storage medium. The proposed method logs events that the database of a file system, “Folder”, is changed. The remaining file can be detected by tracing the sequence of logs using path/file-name matching. Our experimental result suggests that the proposed method can accurately detect remaining files left on the computer.

抄録全体を表示