IEEJ Transactions on Electronics, Information and Systems
Online ISSN : 1348-8155
Print ISSN : 0385-4221
ISSN-L : 0385-4221
Volume 131 , Issue 4
Showing 1-36 articles out of 36 articles from the selected issue
Special Issue on “Prediction, and Control Based on Data”
Preface
Special Issue Review
  • Manabu Kano
    2011 Volume 131 Issue 4 Pages 710-717
    Published: April 01, 2011
    Released: April 01, 2011
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    This paper aims to reveal real problems in the process industry and introduce recent development to solve such problems from the viewpoint of effective use of operation data. Two topics are discussed: virtual sensor and process control. First, in order to clarify the present state and problems, a part of our recent questionnaire survey of process control is quoted. It is emphasized that maintenance is a key issue not only for soft-sensors but also for controllers. Then, new techniques are explained. The first one is correlation-based just-in-time modeling (CoJIT), which can realize higher prediction performance than conventional methods and simplify model maintenance. The second is extended fictitious reference iterative tuning (E-FRIT), which can realize data-driven PID control parameter tuning without process modeling. The great usefulness of these techniques are demonstrated through their industrial applications.
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  • Masatoshi Ogawa, Harutoshi Ogai
    2011 Volume 131 Issue 4 Pages 718-721
    Published: April 01, 2011
    Released: April 01, 2011
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    Recently, attention has been drawn to the local modeling techniques of a new idea called “Just-In-Time (JIT) modeling”. To apply “JIT modeling” to a large amount of database online, “Large-scale database-based Online Modeling (LOM)” has been proposed. LOM is a technique that makes the retrieval of neighboring data more efficient by using both “stepwise selection” and quantization. In order to predict the long-term state of the plant without using future data of manipulated variables, an Extended Sequential Prediction method of LOM (ESP-LOM) has been proposed. In this paper, the LOM and the ESP-LOM are introduced.
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  • Masami Saeki
    2011 Volume 131 Issue 4 Pages 722-725
    Published: April 01, 2011
    Released: April 01, 2011
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    Data-driven design methods are reviewed briefly, and a new PID control design method for stable plants is presented. A linear constraint on the loop transfer function is introduced and the optimal solution can be obtained by solving a linear programming problem once. Adequacy of the constraint is explained from desirable closed-loop transfer functions.
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Special Issue Paper
<Biomedical Engineering>
  • Jiro Kanaya, Munehiro Nakamura, Masahiro Araki, Hiroshi Yokawa, Koji A ...
    2011 Volume 131 Issue 4 Pages 726-735
    Published: April 01, 2011
    Released: April 01, 2011
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    With increase of aged people in Japan, cases of diseases in bladder are increased. Hence, incidents of death due to bladder cancer are increasing nowadays. Cystoscope is the most essential tool in examination of bladder. Although CT, MRI, and ultrasonography are painless examinations, they lack in accuracy. There are two kinds of cystoscopes namely rigid and flexible. The examination with the latter one is painless and is used widely. In handling of flexible cystoscope, medical doctors need to observe the whole inner wall of bladder regulating the direction of the tip, rotation on the cystoscope’s axis, and depth of insertion. However, beginners handling this equipment tend to lose track of the observation resulting in poor characteristics of images obtained from the cystoscope. Sometimes they would pass over some parts in the whole bladder. As the preprocessing of a system for thorough observation, this paper proposes a method for estimating the handling techniques of the cystoscope using neural networks to images obtained from the cystoscope.
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  • Nozomu Araki, Yuki Hoashi, Yasuo Konishi, Kunihiko Mabuchi, Hiroyuki I ...
    2011 Volume 131 Issue 4 Pages 736-741
    Published: April 01, 2011
    Released: April 01, 2011
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    This paper proposed an active finger recognition method using Bayesian filter in order to control a myoelectric hand. We have previously proposed a finger joint angle estimation method based on measured surface electromyography (EMG) signals and a linear model. However, when we estimate 2 or more finger angles by this estimation method, the estimation angle of the inactive finger is not accurate. This is caused by interference of surface EMG signal. To solve this interference problem, we proposed active finger recognition method from the amplitude spectrum of surface EMG signal using Bayesian filter. To confirm the effectiveness of this recognition method, we developed a myoelectric hand simulator that implements proposed recognition algorithm and carried out real-time recognition experiment.
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<Systems, Instrument, Control>
  • Osamu Kaneko, Yusuke Wadagaki, Shigeru Yamamoto
    2011 Volume 131 Issue 4 Pages 742-750
    Published: April 01, 2011
    Released: April 01, 2011
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    In this paper, we consider the data driven approach to the parameter tuning of a controller used for time-delay systems. The first author once proposed the fictitious reference iterative tuning (which is abbreviated as the FRIT) which yields the desired parameter of a controller by using only one-shot experimental data instead of mathematical models of a plant. Thus the FRIT is an effective and useful tuning method from the practical points of view in the sense that the required time and cost can be drastically reduced. This paper extends the FRIT to the parameter tuning of the Smith compensator for time-delay systems. It is well known that the Smith compensator is an effective controller for time-delay systems when we have mathematical models of a plant with time-delay. We show that the FRIT is effectively applicable to the parameter tuning of the Smith compensator under the situation in which we do not have mathematical models of a plant. Particularly, by introducing the special structure for the feedback controller used in the Smith compensator, we show that such a structure enables us to obtain not only the desired parameter of a controller but also the mathematical model of a plant. Finally, we also give a numerical example and an experimental one in order to show the validity of the proposed methods.
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  • Yoshihiro Matsui, Tomohiko Kimura, Kazushi Nakano
    2011 Volume 131 Issue 4 Pages 751-757
    Published: April 01, 2011
    Released: April 01, 2011
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    In this paper, a simple scheme to estimate frequency transfer functions of linear time-invariant single-input single-output systems based on closed-loop step response data is investigated. The method uses only a single set of step response data of plants under closed-loop operating conditions. The input and output of a plant are filtered by a simple bandpass filter, and the frequency transfer function of the plant is obtained with the Discrete Fourier Transforms of the filtered input and output signals. The method is applied to a resonant mechanical system and its validity is illustrated through simulations and experiments.
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  • Masami Saeki, Kyosuke Ogawa
    2011 Volume 131 Issue 4 Pages 758-763
    Published: April 01, 2011
    Released: April 01, 2011
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    In this paper, a gain scheduled PID control system is constructed for a nonlinear plant whose steady state changes by the setpoint change. Our data-driven loop shaping method is applied to the direct design of PID gains using the plant input output response measured at several setpoints. The reference input is used for the scheduling parameter. Usefulness of our method is shown by simulation for a Hammerstein model.
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  • Takao Sato, Akira Inoue
    2011 Volume 131 Issue 4 Pages 764-772
    Published: April 01, 2011
    Released: April 01, 2011
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    This paper proposes a new method for designing a multirate output feedback (MROF) control system, where the update interval of the control input is an integer multiple of the sampling interval of the plant output. In the MROF method, the state variable is calculated without the observer. In this study, a conventional MROF system is extended with the latest information of a plant, and hence, new design parameters are obtained independently of the calculation of the state variable. As a result, the proposed method can resolve the quantization error independently of the calculation of the state variable and improve the control performance compared with conventional methods in which the latest information is not employed. Furthermore, the obtained control structure can be simpler than conventional methods. To demonstrate the effectiveness of the proposed method, it is applied to a linear system and a nonlinear system, and the control results are compared with conventional methods.
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  • Kazuhiro Yubai, Shinya Terada, Junji Hirai
    2011 Volume 131 Issue 4 Pages 773-780
    Published: April 01, 2011
    Released: April 01, 2011
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    In model-free controller syntheses, we have no idea whether the designed controller stabilizes the resulting closed-loop system before its implementation. From the view point of safety of the experimental equipment, we should develop the stability test for model-free controller synthesis using the acquired input/output data. Karimi et al. introduced the sufficient stability condition for the closed-loop system and proposed the stability test for NCbT (Noniterative Correlation-based Tuning) for SISO systems. However, since the positions of the plant and the controller have to be swapped in NCbT, its applicability is restricted to SISO systems.
    This paper proposes to extend the stability test for NCbT to MIMO systems. The basic idea is to use the special reference r[i](t) and to acquire input/output data as many times as the number of plant inputs. The small-gain theorem introduces the sufficient stability condition for the closed-loop system in terms of the H norm of the specific transfer function matrix, which is estimated from the acquired input/output data by the spectral analysis method.
    The effectiveness of the proposed stability test is confirmed by the numerical experiment for LV100 gas turbine engine model and the experiment for tension-and-speed control apparatus.
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  • Kento Tsutsumi, Toru Yamamoto
    2011 Volume 131 Issue 4 Pages 781-787
    Published: April 01, 2011
    Released: April 01, 2011
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    This paper describes a design of internal model controllers base on the data-driven (DD) approach. The internal model control (IMC) has a simple structure and has a high robustness for system uncertainties. However, there are few studies of IMC schemes for nonlinear systems. On the other hand, lots of controlled systems have the nonlinearity. It is difficult to obtain good control performances in the use of such a simple method. In recently years, some more effective control methods are demanded by a reason that the competition of the industrial world has intensified. Then, the DD approach is applied to the IMC in this paper. According to the DD approach, some local models are automatically generated based on input/output data pairs of the controlled object stored in the database. This scheme can adjust the internal model parameters in the on-line manner even if reference signals are changed. Finally, the effectiveness of the newly proposed control scheme is numerically evaluated on some simulation examples in comparison with the conventional control methods for nonlinear systems.
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  • Shiro Masuda, Kyohei Takeda
    2011 Volume 131 Issue 4 Pages 788-793
    Published: April 01, 2011
    Released: April 01, 2011
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    This paper considers controller parameters tuning method for regulator problems using FRIT method. The FRIT method for regulator problems tunes the control parameters so that the disturbance response follows the reference model output. The paper tries to give a method for estimating disturbances for an FRIT method using input-output data generated by disturbances. The proposed method assumes that the disturbance is an impulse-type signal, but its magnitude is unknown, and estimates the magnitude of the disturbance, while it obtains the control parameters simultaneously. Hence, the proposed method gives an FRIT method for regulator problems by only using one-shot input-output data for unknown impulse-type distrubances. The efficiency of the proposed method can be shown through a numerical example.
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  • Kayoko Hayashi, Toru Yamamoto
    2011 Volume 131 Issue 4 Pages 794-799
    Published: April 01, 2011
    Released: April 01, 2011
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    PID control is a common and an effective approach in process control represented by oil plants and chemical plants. However, it is important to determine suitable PID gains included in the PID controller because the control performance strongly depends on these PID gains. Lots of PID tuning methods have been proposed up to now, however, the computed PID gains cannot be employed directly for real plants. In addition, the system model is required in computing PID gains, and the accuracy of the model influences to the control performance. In this paper, a new design scheme of PID controllers without using the system model in computing PID gains. That is, PID gains can be derived by using only the operating (input/output) data. Concretely, the generalized output is newly derived from the PID control law, and the PID gains are computed by using the genetic algorithm so that the generalized output approaches to the system output. As a result, the suitable PID gains can be obtained, which the system output approaches to the reference model output. Finally, in order to illustrate the effectiveness of the proposed scheme, some simulation examples are discussed.
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<Media Information, User Interface>
  • Ayuko Shigeta, Takeshi Koike, Kazuhiko Hamamoto, Kiyoshi Nosu
    2011 Volume 131 Issue 4 Pages 800-807
    Published: April 01, 2011
    Released: April 01, 2011
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    This paper proposes an estimation method of subjective difficulty of Web based English listening tests from Mahalanobis distance of users’ eye movement characteristic parameters. The eye movements characteristics used to distinguish emotions were obtained by examinations of the 10 subjects (5 male, 5 female). The estimated subjective difficulty was measured time sequentially. So that, the periods of “ease” emotion and “difficulty” emotion were selected. The 6 eye movement characteristic parameters used for estimation of users’ subjective difficulty it as follows: (a) average eye movement velocity (b) total direction of gaze X (c) total direction of gaze Y (d) standard deviation of total direction of gaze X (e) standard deviation of total direction of gaze Y (g) count of blinks. The coincidence rate of “ease” was 85.1% and “difficulty” was 87.5%.
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Special Issue Letter
<Energy, Environment and Sustainability>
  • Shuki Inoue, Eiji Mimura, Shingo Aoki, Hiroshi Tsuji
    2011 Volume 131 Issue 4 Pages 808-809
    Published: April 01, 2011
    Released: April 01, 2011
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    To save home energy consumption, this paper proposes an indirect load control based on transaction data. The indirect load control consists of (1) stores a lot of transaction data with consumers’ attribute and their life style, (2) shows the positional data in the same category consumers for diagnosis, (3) notifies a consumer his status, (4) expect him to control their energy consumption indirectly. The paper shows the possibility for box chart in showing positional data and for information entropy calculation in generating consumer’s categories as preliminary survey.
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Paper
<Electrical and Electronic Circuit, LSI>
<Information and Communication Technology>
  • Hongbo Shi, Tomoki Hamagami
    2011 Volume 131 Issue 4 Pages 818-825
    Published: April 01, 2011
    Released: April 01, 2011
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    There are various wireless communication technologies, such as 3G, WiFi, used widely in the world. Recently, not only the laptop but also the smart phones can be equipped with multiple wireless devices. The communication terminals which are implemented with multiple interfaces are usually called multi-homed nodes. Meanwhile, a multi-homed node with multiple interfaces can also be regarded as multiple single-homed nodes. For example, when a person who is using smart phone and laptop to connect to the Internet concurrently, we may regard the person as a multi-homed node in the Internet. This paper proposes a new routing method, Multi-homed Mobile Cross-layer Control to handle multi-homed mobile nodes. Our suggestion can provide a distributed end-to-end routing method for handling the communications among multi-homed nodes at the fundamental network layer.
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<Biomedical Engineering>
  • Tsunemasa Saiki, Yukako Takizawa, Tsutomu Hashizume, Kohei Higuchi, Ta ...
    2011 Volume 131 Issue 4 Pages 826-832
    Published: April 01, 2011
    Released: April 01, 2011
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    In order to establish monitoring systems for home health in elderly people including the prevention of mental illness, we investigated the acceleration of teeth in utterance on the assumption that an acceleration sensor can be implanted into an artificial denture in the near future. In the experiment, an acceleration sensor was fixed in front of the central incisors on the lower jaw by using a denture adhesive, and female and male subjects spoke five Japanese vowels. We then measured the teeth accelerations in three (front-to-back, right-to-left and top-to-bottom) axes and conducted frequency analyses. The result showed that high power spectral densities of the teeth accelerations were observed at a low frequency range of 2-10Hz (both the female and the male) and at a high frequency range of 200-300Hz (the female) or 100-150 Hz (the male). The low and high frequency components indicate movements of the lower jaw and voice sounds by bone conduction, respectively. Especially in the top-to-bottom axis of the central incisor, the frequency component appeared to be significant. Therefore, we found that utterance can be efficiently detected using the acceleration in this axis. We also found that three conditions of normal speech, lip synchronizing and humming can be recognized by using frequency analysis of the acceleration in the top-to-bottom axis of the central incisor.
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  • Michiko Sugawara, Wonjun Choi, Jun Nakanishi, Kazuo Yamaguchi, Hideo Y ...
    2011 Volume 131 Issue 4 Pages 833-839
    Published: April 01, 2011
    Released: April 01, 2011
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    It is well known that cell migrations play a key role in the living systems. From the basic technical point of view, cell migration control is one of the important and useful ways to clarify the mechanism of the cell migration qualitatively and quantitatively. For the purpose of high-resolution control and observation of the cell migrations, which is the goal of this research, in this study, an attempt was made to establish the fabrication process of micro-patterns on caged cell-culturing substrates using inverted microscope with high magnification objective lens. With the combination of fluorescence antibody technique, the adequate ultraviolet (UV) lay exposure time was obtained for the formation of micro-patterns of fibronectin on the caged cell-culturing substrates. We also confirmed that it was possible to control the position of micro-patterns by the primary and secondary UV exposure. In addition, Swiss 3T3 cell culture experiment demonstrated that the initial shape of the cell could be restricted by the primary UV exposure and that the secondary UV exposure was remarkably useful to control the cell migration.
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<Systems, Instrument, Control>
  • Yasuhiko Mutoh
    2011 Volume 131 Issue 4 Pages 840-846
    Published: April 01, 2011
    Released: April 01, 2011
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    A simple design method of the Luenberger observer for linear time-varying systems is proposed in this paper. The paper first propose the simple calculation method to derive the pole placement feedback gain vector for linear time-varying systems. For this purpose, it is shown that the pole placement controller can be derived simply by finding some particular "output signal" such that the relative degree from the input to this output is equal to the order of the system. Using this fact, the feedback gain vector can be calculated directly from plant parameters without transforming the system into any standard form. Then, this method is applied to the design of the observer, i.e., because of the duality of linear time-varying system, the state observer can be derived by un-stabilization of the state error equation.
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  • Takashi Kitayama, Tomoaki Nakano, Shin Yamamoto, Muneo Yamada, Yuta Do ...
    2011 Volume 131 Issue 4 Pages 847-853
    Published: April 01, 2011
    Released: April 01, 2011
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    There is no clear criterion yet for evaluating wipers based on performances of wiping raindrops and visibility in forward view. In the visibility evaluation, it is important to examine spatial frequency and contrast of forward view. In this paper, we propose a new method for evaluating wiper performances based on visibility in forward view. Spatial frequency and contrast of image in the footage which were affected by the raindrops are calculated based on them of background board which were printed stripe patterns. The variations with time of power spectrum and decreased contrast are synchronized with the motion of the wiper for the all experimental cases. These results show that to evaluate wiping performance is possible by the method which we proposed.
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  • Masaki Kobayashi, Hiroyuki Kondo, Naoto Sasaoka, Yoshio Itoh
    2011 Volume 131 Issue 4 Pages 854-859
    Published: April 01, 2011
    Released: April 01, 2011
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    In this paper we propose a series-parallel adaptive algorithm using the square sum of the correlation function and its convergence condition. It is known well that this adaptive algorithm is robust for the near-end noise since that does not have the bias error of the adaptive weights but the loop gain ensuring the convergence is not clear. We show that the independent adaptive control of two adaptive filters is possible and formulate the convergence condition of the loop gain. The analytical results and the above mentioned feature are verified by computer simulation.
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  • Mitsuhiro Kadota, Shinji Doki, Shigeru Okuma
    2011 Volume 131 Issue 4 Pages 860-869
    Published: April 01, 2011
    Released: April 01, 2011
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    This paper describes the application of model predictive control (MPC) to current control system of permanent magnet synchronous motor (PMSM). Proposed current control system considers switching states of inverter as controller output, while conventional one regards the inverter as ideal amplifier. The problem with deciding the switching state to output is formulated based on MPC, which uses the mathematical model of PMSM for prediction of future motor current and the objective function deciding the optimal switching state. This function is based on not only minimization of the error between the predicted motor current and the current reference, but actual requirements for current control system such as reduction of inverter switching times. Simulation results show that current transient response improves by proposed system, especially at the region where voltage saturation occurs.
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<Intelligence, Robotics>
  • Yo Kobayashi, Jaesung Hong, Ryutaro Hamano, Makoto Hashizume, Kaoru Ok ...
    2011 Volume 131 Issue 4 Pages 870-879
    Published: April 01, 2011
    Released: April 01, 2011
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    Central venous catheterization is a procedure, which a doctor insert a catheter into the patient’s vein for transfusion. Since there are risks of bleeding from arterial puncture or pneumothorax from pleural puncture. Physicians are strictly required to make needle reach up into the vein and to stop the needle in the middle of vein. We proposed a robot system for assisting the venous puncture, which can relieve the difficulties in conventional procedure, and the risks of complication. This paper reports the design structuring and experimental results of needle insertion manipulator. First, we investigated the relationship between insertion force and angle into the vein. The results indicated that the judgment of perforation using the reaction force is possible in case where the needling angle is from 10 to 20 degree. The experiment to evaluate accuracy of the robot also revealed that it has beyond 0.5 mm accuracy. We also evaluated the positioning accuracy in the ultrasound images. The results displays that the accuracy is beyond 1.0 mm and it has enough for venous puncture. We also carried out the venous puncture experiment to the phantom and confirm our manipulator realized to make needle reach up into the vein.
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<Media Information, User Interface>
<Speech and Image Processing, Recognition>
  • Satoshi Nishino, Shun Yasuda
    2011 Volume 131 Issue 4 Pages 890-899
    Published: April 01, 2011
    Released: April 01, 2011
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    The near infrared ray spectral characteristic of a person’s cheeks was simulated in this paper, and it was confirmed that the spectral characteristic of the cheeks part by the near infrared rays was detected at the subcutaneous fat under 2mm of the skin. Therefore, subcutaneous fat has a great influence at the near infrared ray spectral characteristic. Concretely, when subcutaneous fat thickness is thick, the absorbance falls down, and the spectral characteristic around 1200nm is the same for an acute angle, and becomes the spectral characteristic of the female. On the other hand, increasing the water content to simulate the increase in the thickness of the subcutaneous fat, the light absorbance rises, and the acute angle of the spectral characteristic around 1200nm disappears. The 1200nm characteristic becomes that of the male’s spectral characteristic which shows a rounded form. From the discussion above, it could be verified that a difference in the subcutaneous fat thickness is the factor of the difference in the near infrared ray spectral characteristics between that of a male and female cheek.
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<Softcomputing, Learning>
  • Alick Nguvulu, Shoso Yamato, Toshihisa Honma
    2011 Volume 131 Issue 4 Pages 900-905
    Published: April 01, 2011
    Released: April 01, 2011
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    Recently a Project Assessment Indicator (PAI) Model has been applied in the Project Management Field. The PAI Model output or PAI indicates the entire project performance at the current but not at the future time. We use a neural network (NN) to predict the project performance based on past PAI data. The NN model has been tested on monthly PAI and virtual weekly PAI generated using the 2nd Newton Interpolation Function. Generating weekly PAI using our approach helps to increase the dataset size for training the neural predictor model and allows the project manager to make weekly predictions of project performance. The project manager may then have quantitative estimates of the future performance of the project at intervals shorter than one month. PAI is normally reported on a monthly basis. The NN model performance is evaluated using the Mean Absolute Percantage Error. We achieve a predictive accuracy ranging from 1.21% to 2.87% on the test data of the virtual weekly PAIs. This suggests that depending on the dataset size, project managers could use the NN model to predict future project performance to about 1.21% ∼ 2.87% of the weekly PAI value.
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  • Munehiro Nakamura, Jiro Kanaya, Haruhiko Kimura
    2011 Volume 131 Issue 4 Pages 906-917
    Published: April 01, 2011
    Released: April 01, 2011
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    This paper presents a system for estimating handling of a flexible cystoscope in bladder checkup. In the checkup, all the seven parts of the bladder wall can be observed with a flexible cystoscope. However, since the shape and color of the parts are depended on participants and five of the parts have same shape and color, it is difficult to grasp the location that the cystoscope is projecting. For the reason, it is often happened that urologists can not confirm that all the parts were observed. Since urologists conduct the checkup by handling the cystoscope and watching movement of the location that the cystoscope is projecting, reproducing the checkup by a computer would recognize oversights. And then, the proposed method extracts movement of the location and estimates the handling by the neural network. The experimental results of the estimations for 9 videos recorded in the checkup have shown a possibility of reproducing the checkup.
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<Information System, Electronic Commerce>
  • Masaru Unno, Hua Xu
    2011 Volume 131 Issue 4 Pages 918-925
    Published: April 01, 2011
    Released: April 01, 2011
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    In this paper, we consider a revenue-sharing and network investment problem between an Internet service provider (ISP) and a content provider (CP) by applying the dynamic agency theory. We formulate the problem as the principal-agent problem where the ISP is the principal and the CP is the agent. The principal-agent problem is transformed to a stochastic optimal control problem in which the objectives of ISP are to find an optimal revenue-sharing strategy and a network investment strategy, and to advise an incentive compatible effort level to the CP. The sufficient conditions for the existence of the optimal revenue-sharing strategy, the optimal investment strategy and the incentive compatible effort to the CP are obtained. A numerical example is solved to show the existence of such strategies. The practical implications of the results obtained in the paper will also be discussed.
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<Information Processing, Software>
  • Yuichiro Mori, Koichi Asakura, Toyohide Watanabe
    2011 Volume 131 Issue 4 Pages 926-933
    Published: April 01, 2011
    Released: April 01, 2011
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    In this paper, we propose a power-aware scheduling algorithm for reducing power consumption especially for highly-loaded processors without increasing the makespan of programs. In our algorithm, Dynamic Voltage Scaling (DVS) is applied to tasks which are not on the critical path of a schedule. In order to find tasks which can be applied DVS, we introduce a concept of slack-time. Slack-time represents the amount of redundant time for delaying completion time of a task without increasing the makespan of the schedule. In our algorithm, firstly, slack-time is calculated for each task. Then, tasks are selected based on a greedy method. In this mechanism, DVS is applied to tasks that have slack-time in decreasing order of reducing power consumption. Experimental results show that our algorithm can reduce about 10.6% and 16.5% of power consumption on 4 and 8 processors respectively on average.
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Letter
<Systems, Instrument, Control>
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