start-ver=1.4
cd-journal=joma
no-vol=12
cd-vols=
no-issue=
article-no=
start-page=28201
end-page=28211
dt-received=
dt-revised=
dt-accepted=
dt-pub-year=2024
dt-pub=20240212
dt-online=
en-article=
kn-article=
en-subject=
kn-subject=
en-title=
kn-title=WLAN Channel Status Duration Prediction for Audio and Video Services Using Probabilistic Neural Networks
en-subtitle=
kn-subtitle=
en-abstract=
kn-abstract=Due to massive increase in wireless access from smartphones, IoT devices, WLAN is aiming to improve its spectrum efficiency (SE) using many technologies. Some interesting techniques for WLAN systems are flexible allocation of frequency resource and cognitive radio (CR) techniques which expect to find more useful spectrum resource by modeling and then predicting of channel status using the captured statistics information of the used spectrum. This paper investigates the prediction accuracy of busy/idle duration of two major wireless services: audio service and video service using neural network based predictor. We first study the statistics distribution of their time-series busy/idle (B/I) duration, and then analyze the predictability of the busy/idle duration based on the predictability theory. Then, we propose a data categorization (DC) method which categorizes the duration of recent B/I duration according the their ranges to make the duration of next data be distributed into several streams. From the predictability analysis of each stream and the prediction performance using the probabilistic neural network (PNN), it can be confirmed that the proposed DC can improve the prediction accuracy of time-series data in partial streams.
en-copyright=
kn-copyright=

en-aut-name=HouYafei
en-aut-sei=Hou
en-aut-mei=Yafei
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=1
ORCID=

en-aut-name=DennoSatoshi
en-aut-sei=Denno
en-aut-mei=Satoshi
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=2
ORCID=

affil-num=1
en-affil=Faculty of Environmental, Life, Natural Science and Technology, Okayama University
kn-affil=

affil-num=2
en-affil=Faculty of Environmental, Life, Natural Science and Technology, Okayama University
kn-affil=
en-keyword=Wireless LAN
kn-keyword=Wireless LAN
en-keyword=Wireless communication
kn-keyword=Wireless communication
en-keyword=Media streaming
kn-keyword=Media streaming
en-keyword=Wireless sensor networks
kn-keyword=Wireless sensor networks
en-keyword=Resource management
kn-keyword=Resource management
en-keyword=Probability distribution
kn-keyword=Probability distribution
en-keyword=Channel allocation
kn-keyword=Channel allocation
en-keyword=Audio-visual systems
kn-keyword=Audio-visual systems
en-keyword=Data processing
kn-keyword=Data processing
en-keyword=Predictive models
kn-keyword=Predictive models
en-keyword=Neural networks
kn-keyword=Neural networks
en-keyword=Channel status duration prediction
kn-keyword=Channel status duration prediction
en-keyword=WLAN audio/video traffic
kn-keyword=WLAN audio/video traffic
en-keyword=data predictability analysis
kn-keyword=data predictability analysis
en-keyword=probabilistic neural network (PNN)
kn-keyword=probabilistic neural network (PNN)
END

start-ver=1.4
cd-journal=joma
no-vol=11
cd-vols=
no-issue=
article-no=
start-page=109435
end-page=109447
dt-received=
dt-revised=
dt-accepted=
dt-pub-year=2023
dt-pub=20231004
dt-online=
en-article=
kn-article=
en-subject=
kn-subject=
en-title=
kn-title=A Proposal of an Axial-Flux Permanent-Magnet Machine Employing SMC Core With Tooth-Tips Constructed by One-Pressing Process: Improving Torque and Manufacturability
en-subtitle=
kn-subtitle=
en-abstract=
kn-abstract=This study aims to improve the torque performance and manufacturability of axial-flux permanent magnet (AFPM) machines. Hence, we propose a novel AFPM machine that employs a soft magnetic composite (SMC) core with tooth-tips constructed by a one-pressing process and die. In this paper, the proposed AFPM machine is compared to two conventional AFPM machines using an SMC core. One of them has open-slot structure without tooth-tips. Another model employs an SMC core with tooth-tips pressed by a conventional pressing process that requires multiple operations and dies. As a result of the comparison, the proposed AFPM machine realizes a much higher torque than the two conventional machines. Additionally, the manufacturability of an SMC core with tooth-tips pressed by the proposed method is superior to the conventional one because the proposed structure can be realized by the one-pressing process and die. Furthermore, two prototypes of the proposed AFPM machine and the conventional one with an open-slot structure are fabricated, and then, they are compared by experiments. Consequently, the proposed AFPM machine achieves a 15.7% higher torque than that of the conventional machine using an open-slot structure. Finally, this paper presents an improved design of an AFPM machine with SMC cores using the proposed pressing process. As a result, the proposed AFPM realizes a 20% larger torque than that of a conventional model employing an open-slot structure.
en-copyright=
kn-copyright=

en-aut-name=TsunataRen
en-aut-sei=Tsunata
en-aut-mei=Ren
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=1
ORCID=

en-aut-name=TakemotoMasatsugu
en-aut-sei=Takemoto
en-aut-mei=Masatsugu
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=2
ORCID=

en-aut-name=ImaiJun
en-aut-sei=Imai
en-aut-mei=Jun
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=3
ORCID=

en-aut-name=SaitoTatsuya
en-aut-sei=Saito
en-aut-mei=Tatsuya
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=4
ORCID=

en-aut-name=UenoTomoyuki
en-aut-sei=Ueno
en-aut-mei=Tomoyuki
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=5
ORCID=

affil-num=1
en-affil=Graduate School of Environmental, Life, Natural Science and Technology, Okayama University
kn-affil=

affil-num=2
en-affil=Graduate School of Environmental, Life, Natural Science and Technology, Okayama University
kn-affil=

affil-num=3
en-affil=Graduate School of Environmental, Life, Natural Science and Technology, Okayama University
kn-affil=

affil-num=4
en-affil=Sumitomo Electric Industries Ltd.
kn-affil=

affil-num=5
en-affil=Sumitomo Electric Industries Ltd.
kn-affil=
en-keyword=Pressing
kn-keyword=Pressing
en-keyword=Stator cores
kn-keyword=Stator cores
en-keyword=Magnetic cores
kn-keyword=Magnetic cores
en-keyword=Torque
kn-keyword=Torque
en-keyword=Atmospheric modeling
kn-keyword=Atmospheric modeling
en-keyword=Presses
kn-keyword=Presses
en-keyword=Manufacturing
kn-keyword=Manufacturing
en-keyword=Mass production
kn-keyword=Mass production
en-keyword=Axial-flux permanent magnet machine
kn-keyword=Axial-flux permanent magnet machine
en-keyword=soft magnetic composite (SMC)
kn-keyword=soft magnetic composite (SMC)
en-keyword=PMSM
kn-keyword=PMSM
en-keyword=tooth-tips
kn-keyword=tooth-tips
en-keyword=torque
kn-keyword=torque
en-keyword=press process
kn-keyword=press process
en-keyword=semi-closed slot structure
kn-keyword=semi-closed slot structure
en-keyword=axial gap motor
kn-keyword=axial gap motor
en-keyword=mass production
kn-keyword=mass production
en-keyword=YASA motor
kn-keyword=YASA motor
en-keyword=shoe
kn-keyword=shoe
END

start-ver=1.4
cd-journal=joma
no-vol=11
cd-vols=
no-issue=
article-no=
start-page=82024
end-page=82036
dt-received=
dt-revised=
dt-accepted=
dt-pub-year=2023
dt-pub=20230803
dt-online=
en-article=
kn-article=
en-subject=
kn-subject=
en-title=
kn-title=Design and Analysis of Hybrid-Excitation Variable Flux Memory Motor for Traction Applications: Improving Output Power in High-Speed Area During Six-Step Operation Mode
en-subtitle=
kn-subtitle=
en-abstract=
kn-abstract=Variable flux motors with adjustable magnetic flux have been gaining attention because of their capability to simultaneously achieve a high torque density and high efficiency. In addition, the output power characteristic, which is related to acceleration performance, in high-speed areas is important in traction applications. However, typical traction motors have lower output power in high-speed areas. In this paper, a Hybrid-Excitation Variable Flux Memory Motor (HE-VFMM) is therefore proposed to enhance output power characteristics under six-step operation mode in high-speed area. The proposed HE-VFMM can perform magnetic flux adjustment with two components: field winding and variable flux permanent magnet (VPM), thus dramatically increasing flux adjustment range. The simulation results show the proposed HE-VFMM achieves 23.7% higher output power at 17,000 rpm than that of an existing traction motor in Prius 4th generation that has the same size while maintaining high efficiency in the frequently used operating area. Additionally, it was found that variable magnetic flux is very effective in enhancing the output power, especially in the high-speed region because the magnetic saturation in the stator core is mitigated by field-weakening control. Consequently, as the rotational speed increases, an increase ratio of the output power caused by the adjustable magnetic flux becomes higher. This paper shows that the proposed HE-VFMM is an effective method for improving the problem of low output power in high-speed regions in traction motors.
en-copyright=
kn-copyright=

en-aut-name=TsunataRen
en-aut-sei=Tsunata
en-aut-mei=Ren
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=1
ORCID=

en-aut-name=YokomichiKeito
en-aut-sei=Yokomichi
en-aut-mei=Keito
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=2
ORCID=

en-aut-name=TakemotoMasatsugu
en-aut-sei=Takemoto
en-aut-mei=Masatsugu
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=3
ORCID=

en-aut-name=ImaiJun
en-aut-sei=Imai
en-aut-mei=Jun
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=4
ORCID=

affil-num=1
en-affil=Graduate School of Environmental, Life, Natural Science and Technology, Okayama University
kn-affil=

affil-num=2
en-affil=Graduate School of Environmental, Life, Natural Science and Technology, Okayama University
kn-affil=

affil-num=3
en-affil=Graduate School of Environmental, Life, Natural Science and Technology, Okayama University
kn-affil=

affil-num=4
en-affil=Graduate School of Environmental, Life, Natural Science and Technology, Okayama University
kn-affil=
en-keyword=Variable flux memory motor
kn-keyword=Variable flux memory motor
en-keyword=hybrid excitation motor
kn-keyword=hybrid excitation motor
en-keyword=traction applications
kn-keyword=traction applications
en-keyword=EV
kn-keyword=EV
en-keyword=HEV
kn-keyword=HEV
en-keyword=six-step operation
kn-keyword=six-step operation
en-keyword=one-pulse drive
kn-keyword=one-pulse drive
en-keyword=output power density
kn-keyword=output power density
END

start-ver=1.4
cd-journal=joma
no-vol=11
cd-vols=
no-issue=
article-no=
start-page=52750
end-page=52762
dt-received=
dt-revised=
dt-accepted=
dt-pub-year=2023
dt-pub=20230529
dt-online=
en-article=
kn-article=
en-subject=
kn-subject=
en-title=
kn-title=Stargazer: Long-Term and Multiregional Measurement of Timing/ Geolocation-Based Cloaking
en-subtitle=
kn-subtitle=
en-abstract=
kn-abstract=Malicious hosts have come to play a significant and varied role in today's cyber attacks. Some of these hosts are equipped with a technique called cloaking, which discriminates between access from potential victims and others and then returns malicious content only to potential victims. This is a serious threat because it can evade detection by security vendors and researchers and cause serious damage. As such, cloaking is being extensively investigated, especially for phishing sites. We are currently engaged in a long-term cloaking study of a broader range of threats. In the present study, we implemented Stargazer, which actively monitors malicious hosts and detects geographic and temporal cloaking, and collected 30,359,410 observations between November 2019 and February 2022 for 18,397 targets from 13 sites where our sensors are installed. Our analysis confirmed that cloaking techniques are widely abused, i.e., not only in the context of specific threats such as phishing. This includes geographic and time-based cloaking, which is difficult to detect with single-site or one-shot observations. Furthermore, we found that malicious hosts that perform cloaking include those that survive for relatively long periods of time, and those whose contents are not present in VirusTotal. This suggests that it is not easy to observe and analyze the cloaking malicious hosts with existing technologies. The results of this study have deepened our understanding of various types of cloaking, including geographic and temporal ones, and will help in the development of future cloaking detection methods.
en-copyright=
kn-copyright=

en-aut-name=FujiiShota
en-aut-sei=Fujii
en-aut-mei=Shota
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=1
ORCID=

en-aut-name=SatoTakayuki
en-aut-sei=Sato
en-aut-mei=Takayuki
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=2
ORCID=

en-aut-name=AokiSho
en-aut-sei=Aoki
en-aut-mei=Sho
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=3
ORCID=

en-aut-name=TsudaYu
en-aut-sei=Tsuda
en-aut-mei=Yu
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=4
ORCID=

en-aut-name=KawaguchiNobutaka
en-aut-sei=Kawaguchi
en-aut-mei=Nobutaka
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=5
ORCID=

en-aut-name=ShigemotoTomohiro
en-aut-sei=Shigemoto
en-aut-mei=Tomohiro
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=6
ORCID=

en-aut-name=TeradaMasato
en-aut-sei=Terada
en-aut-mei=Masato
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=7
ORCID=

affil-num=1
en-affil=Graduate School of Natural Science and Technology, Okayama University
kn-affil=

affil-num=2
en-affil=Research and Development Group, Hitachi Ltd.
kn-affil=

affil-num=3
en-affil=Research and Development Group, Hitachi Ltd.
kn-affil=

affil-num=4
en-affil=National Institute of Information and Communications Technology
kn-affil=

affil-num=5
en-affil=Research and Development Group, Hitachi Ltd.
kn-affil=

affil-num=6
en-affil=Research and Development Group, Hitachi Ltd.
kn-affil=

affil-num=7
en-affil=Research and Development Group, Hitachi Ltd.
kn-affil=
en-keyword=Cloaking
kn-keyword=Cloaking
en-keyword=cyber security
kn-keyword=cyber security
en-keyword=geofencing
kn-keyword=geofencing
en-keyword=malcious host
kn-keyword=malcious host
en-keyword=time-series
kn-keyword=time-series
END

start-ver=1.4
cd-journal=joma
no-vol=11
cd-vols=
no-issue=
article-no=
start-page=39466
end-page=39483
dt-received=
dt-revised=
dt-accepted=
dt-pub-year=2023
dt-pub=20230413
dt-online=
en-article=
kn-article=
en-subject=
kn-subject=
en-title=
kn-title=Artificial Neural Network Based Audio Reinforcement for Computer Assisted Rote Learning
en-subtitle=
kn-subtitle=
en-abstract=
kn-abstract=The dual-channel assumption of the cognitive theory of multimedia learning suggests that importing a large amount of information through a single (visual or audio) channel overloads that channel, causing partial loss of information, while importing it simultaneously through multiple channels relieves the burden on them and leads to the registration of a larger amount of information. In light of such knowledge, this study investigates the possibility of reinforcing visual stimuli with audio for supporting e-learners in memorization tasks. Specifically, we consider three kinds of learning material and two kinds of audio stimuli and partially reinforce each kind of material with each kind of stimuli in an arbitrary way. In a series of experiments, we determine the particular type of audio, which offers the highest improvement for each kind of material. Our work stands out as being the first study investigating the differences in memory performance in relation to different combinations of learning content and stimulus. Our key findings from the experiments are: (i) E-learning is more effective in refreshing memory rather than studying from scratch, (ii) Non-informative audio is more suited to verbal content, whereas informative audio is better for numerical content, (iii) Constant audio triggering degrades learning performance and thus audio triggering should be handled with care. Based on these findings, we develop an ANN-based estimator to determine the proper moment for triggering audio (i.e. when memory performance is estimated to be declining) and carry out follow-up experiments for testing the integrated framework. Our contributions involve (i) determination of the most effective audio for each content type, (ii) estimation of memory deterioration based on learners' interaction logs, and (iii) the proposal of improvement of memory registration through auditory reinforcement. We believe that such findings constitute encouraging evidence the memory registration of e-learners can be enhanced with content-aware audio incorporation.
en-copyright=
kn-copyright=

en-aut-name=SupitayakulParisa
en-aut-sei=Supitayakul
en-aut-mei=Parisa
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=1
ORCID=

en-aut-name=Y?celZeynep 
en-aut-sei=Y?cel
en-aut-mei=Zeynep 
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=2
ORCID=

en-aut-name=MondenAkito
en-aut-sei=Monden
en-aut-mei=Akito
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=3
ORCID=

affil-num=1
en-affil=Graduate School of Natural Science and Technology, Okayama University
kn-affil=

affil-num=2
en-affil=Graduate School of Natural Science and Technology, Okayama University
kn-affil=

affil-num=3
en-affil=Graduate School of Natural Science and Technology, Okayama University
kn-affil=
en-keyword=Visualization
kn-keyword=Visualization
en-keyword=Electronic learning
kn-keyword=Electronic learning
en-keyword=Task analysis
kn-keyword=Task analysis
en-keyword=Estimation
kn-keyword=Estimation
en-keyword=Vocabulary
kn-keyword=Vocabulary
en-keyword=Memory management
kn-keyword=Memory management
en-keyword=Learning (artificial intelligence)
kn-keyword=Learning (artificial intelligence)
en-keyword=E-learning
kn-keyword=E-learning
en-keyword=neural networks
kn-keyword=neural networks
en-keyword=artificial intelligence
kn-keyword=artificial intelligence
en-keyword=cognitive theory of multimedia learning
kn-keyword=cognitive theory of multimedia learning
en-keyword=cognitive load
kn-keyword=cognitive load
en-keyword=distinctiveness account
kn-keyword=distinctiveness account
en-keyword=perceptual decoupling
kn-keyword=perceptual decoupling
en-keyword=adaptability
kn-keyword=adaptability
en-keyword=educational data mining
kn-keyword=educational data mining
END

start-ver=1.4
cd-journal=joma
no-vol=9
cd-vols=
no-issue=
article-no=
start-page=22688
end-page=22697
dt-received=
dt-revised=
dt-accepted=
dt-pub-year=2021
dt-pub=20210129
dt-online=
en-article=
kn-article=
en-subject=
kn-subject=
en-title=
kn-title=Development of an Eye-Gaze Input System With High Speed and Accuracy through Target Prediction Based on Homing Eye Movements
en-subtitle=
kn-subtitle=
en-abstract=
kn-abstract=In this study, a method to predict a target on the basis of the trajectory of eye movements and to increase the pointing speed while maintaining high predictive accuracy is proposed. First, a predictive method based on ballistic (fast) eye movements (Approach 1) was evaluated in terms of pointing speed and predictive accuracy. In Approach 1, the so-called Midas touch problem (pointing to an unintended target) occurred, particularly when a small number of samples was used to predict a target. Therefore, to overcome the poor predictive accuracy of Approach 1, we developed a new predictive method (Approach 2) using homing (slow) eye movements rather than ballistic (fast) eye movements. Approach 2 overcame the disadvantage (inaccurate prediction) of Approach 1 by shortening the pointing time while maintaining high predictive accuracy.
en-copyright=
kn-copyright=

en-aut-name=MurataAtsuo
en-aut-sei=Murata
en-aut-mei=Atsuo
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=1
ORCID=

en-aut-name=DoiToshihisa
en-aut-sei=Doi
en-aut-mei=Toshihisa
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=2
ORCID=

en-aut-name=KageyamaKazushi
en-aut-sei=Kageyama
en-aut-mei=Kazushi
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=3
ORCID=

en-aut-name=KarwowskiWaldemar
en-aut-sei=Karwowski
en-aut-mei=Waldemar
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=4
ORCID=

affil-num=1
en-affil=Department of Intelligent Mechanical Systems, Graduate School of Natural Science and Technology, Okayama University
kn-affil=

affil-num=2
en-affil=Department of Intelligent Mechanical Systems, Graduate School of Natural Science and Technology, Okayama University
kn-affil=

affil-num=3
en-affil=Department of Intelligent Mechanical Systems, Graduate School of Natural Science and Technology, Okayama University
kn-affil=

affil-num=4
en-affil=Engineering and Management Systems, University of Central Florida
kn-affil=
en-keyword=Eye-gaze input
kn-keyword=Eye-gaze input
en-keyword=target predictive method
kn-keyword=target predictive method
en-keyword=ballistic eye movement
kn-keyword=ballistic eye movement
en-keyword=homing eye movement
kn-keyword=homing eye movement
en-keyword=pointing time
kn-keyword=pointing time
en-keyword=predictive accuracy
kn-keyword=predictive accuracy
en-keyword=Midas touch
kn-keyword=Midas touch
END

start-ver=1.4
cd-journal=joma
no-vol=9
cd-vols=
no-issue=
article-no=
start-page=15929
end-page=15938
dt-received=
dt-revised=
dt-accepted=
dt-pub-year=2021
dt-pub=20210120
dt-online=
en-article=
kn-article=
en-subject=
kn-subject=
en-title=
kn-title=Capacity Loss From Localization Error in MIMO Channel Using Leaky Coaxial Cable
en-subtitle=
kn-subtitle=
en-abstract=
kn-abstract=Leaky coaxial (LCX) cable has been employed as antennas for wireless traffic over many linear-cell scenarios such as railway station, tunnels and shopping malls. In addition, LCX can be used for user localization and wireless power transfer (WPT). Compared with the equal power allocation method, the power allocation method for LCX system using positional information (PI) can improve its capacity with the same level of computational complexity. In this paper, we will investigate the level of capacity loss on the 2.4 GHz and 5 GHz band for the conventional equal power (EP) allocation method, the water-filling (WF) based power allocation, and our proposed low-complexity power allocation method for LCX system with PI. The results show that LCX system with our proposed method using PI can reduce the capacity loss due to localization error than that of others.
en-copyright=
kn-copyright=

en-aut-name=ZhuJunjie
en-aut-sei=Zhu
en-aut-mei=Junjie
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=1
ORCID=

en-aut-name=HouYafei
en-aut-sei=Hou
en-aut-mei=Yafei
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=2
ORCID=

en-aut-name=NagayamaKenta
en-aut-sei=Nagayama
en-aut-mei=Kenta
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=3
ORCID=

en-aut-name=DennoSatoshi
en-aut-sei=Denno
en-aut-mei=Satoshi
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=4
ORCID=

affil-num=1
en-affil=Graduate School of Natural Science and Technology, Okayama University
kn-affil=

affil-num=2
en-affil=Graduate School of Natural Science and Technology, Okayama University
kn-affil=

affil-num=3
en-affil=Graduate School of Natural Science and Technology, Okayama University
kn-affil=

affil-num=4
en-affil=Graduate School of Natural Science and Technology, Okayama University
kn-affil=
en-keyword=Leaky coaxial cable (LCX)
kn-keyword=Leaky coaxial cable (LCX)
en-keyword=LCX-MIMO
kn-keyword=LCX-MIMO
en-keyword=positional information
kn-keyword=positional information
en-keyword=channel capacity
kn-keyword=channel capacity
en-keyword=power allocation
kn-keyword=power allocation
END

start-ver=1.4
cd-journal=joma
no-vol=15
cd-vols=
no-issue=
article-no=
start-page=2069
end-page=2080
dt-received=
dt-revised=
dt-accepted=
dt-pub-year=2019
dt-pub=20191128
dt-online=
en-article=
kn-article=
en-subject=
kn-subject=
en-title=
kn-title=Near-Optimal Detection for Binary Tardos Code by Estimating Collusion Strategy
en-subtitle=
kn-subtitle=
en-abstract=
kn-abstract=A previously proposed optimal detector for bias-based fingerprinting codes such as Tardos and Nuida requires two kinds of important information: the number of colluders and the collusion strategy used to generate the pirated codeword. An estimator has now been derived for these two parameters. The bias in the pirated codeword is measured by observing the number of zeros and ones and compared with possible bias patterns calculated using information about the collusion strategy and number of colluders. Computer simulation demonstrated that the collusion strategy and number of colluders can be estimated with high probability and that the traceability of a detector using the proposed estimator is extremely close to being optimal.
en-copyright=
kn-copyright=

en-aut-name=Yasui Tatsuya
en-aut-sei=Yasui
en-aut-mei= Tatsuya
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=1
ORCID=

en-aut-name=KuribayashiMinoru
en-aut-sei=Kuribayashi
en-aut-mei=Minoru
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=2
ORCID=

en-aut-name=FunabikiNobuo
en-aut-sei=Funabiki
en-aut-mei=Nobuo
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=3
ORCID=

en-aut-name=EchizenIsao
en-aut-sei=Echizen
en-aut-mei=Isao
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=4
ORCID=

affil-num=1
en-affil=Graduate School of Science and Technology, Okayama University
kn-affil=

affil-num=2
en-affil=Graduate School of Science and Technology, Okayama University
kn-affil=

affil-num=3
en-affil=Graduate School of Natural Science and Technology, Okayama University
kn-affil=

affil-num=4
en-affil=National Institute of Informatics
kn-affil=
en-keyword=fingerprinting code
kn-keyword=fingerprinting code
en-keyword=optimal detector
kn-keyword=optimal detector
en-keyword=collusion strategy
kn-keyword=collusion strategy
en-keyword=number of colluders
kn-keyword=number of colluders
en-keyword=estimator
kn-keyword=estimator
END

start-ver=1.4
cd-journal=joma
no-vol=
cd-vols=
no-issue=
article-no=
start-page=185
end-page=190
dt-received=
dt-revised=
dt-accepted=
dt-pub-year=1999
dt-pub=199909
dt-online=
en-article=
kn-article=
en-subject=
kn-subject=
en-title=
kn-title=Application of pneumatic parallel manipulator as haptic human interface
en-subtitle=
kn-subtitle=
en-abstract=
kn-abstract=When humans and robots implement a cooperative task, information (intention) transfer between them is an important problem as the task becomes complicated. In the paper, a haptic interface using a pneumatic parallel manipulator is developed to realize ginformation transfer by means of contacth. The contact information given by the human, namely contact force vector and contact point on the manipulator, is detected by the interface itself and such information is transferred to the robot by being connected with some reference signal. The pneumatic parallel manipulator works as a kind of elastic body even when its position is controlled owing to the air compressibility. Focusing on this characteristic and introducing an idea of compliance center with a spherical shell, contact force vector and contact point are detected without a force sensor. The validity of the proposed method is confirmed through some experiments.
en-copyright=
kn-copyright=

en-aut-name=TakaiwaMasahiro
en-aut-sei=Takaiwa
en-aut-mei=Masahiro
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=1
ORCID=

en-aut-name=NoritsuguToshiro
en-aut-sei=Noritsugu
en-aut-mei=Toshiro
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=2
ORCID=

affil-num=1
en-affil=
kn-affil=Faculty of Engineering, Okayama University

affil-num=2
en-affil=
kn-affil=Faculty of Engineering, Okayama University
en-keyword=Haptic Interface
kn-keyword=Haptic Interface
en-keyword=Pneumatic Driving System
kn-keyword=Pneumatic Driving System
en-keyword=Parallel Manipulator
kn-keyword=Parallel Manipulator
en-keyword=Elastic Characteristic
kn-keyword=Elastic Characteristic
END

start-ver=1.4
cd-journal=joma
no-vol=2
cd-vols=
no-issue=
article-no=
start-page=723
end-page=728
dt-received=
dt-revised=
dt-accepted=
dt-pub-year=1996
dt-pub=19963
dt-online=
en-article=
kn-article=
en-subject=
kn-subject=
en-title=
kn-title=Development of a tactile sensing flexible actuator
en-subtitle=
kn-subtitle=
en-abstract=
kn-abstract=<p>The disadvantages of flexible artificial fingers have been improved. The finger is provided with the tactile sense by two types of sensors to detect when the finger tip touches an object and to estimate both the finger force and object size. The rigidity is enhanced by equipping the finger with a reinforcing material similar to that of human bone. A prototype robot hand with four fingers has been manufactured for experiments and mounted on an industrial articulated robot. The effectiveness of the improved robot hand finger was confirmed throughout experimental tests of grasping action</p>
en-copyright=
kn-copyright=

en-aut-name=TanakaYutaka
en-aut-sei=Tanaka
en-aut-mei=Yutaka
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=1
ORCID=

en-aut-name=GofukuAkio
en-aut-sei=Gofuku
en-aut-mei=Akio
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=2
ORCID=

en-aut-name=FujinoYuji
en-aut-sei=Fujino
en-aut-mei=Yuji
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=3
ORCID=

affil-num=1
en-affil=
kn-affil=Department of Mecliariical Engineering, Faculty of Engineering, Okayama Univ.

affil-num=2
en-affil=
kn-affil=Department of Mecliariical Engineering, Faculty of Engineering, Okayama Univ.

affil-num=3
en-affil=
kn-affil=Murata Seisakusho
en-keyword=actuators
kn-keyword=actuators
en-keyword=manipulators
kn-keyword=manipulators
en-keyword=tactile sensors
kn-keyword=tactile sensors
END

start-ver=1.4
cd-journal=joma
no-vol=
cd-vols=
no-issue=
article-no=
start-page=932
end-page=937
dt-received=
dt-revised=
dt-accepted=
dt-pub-year=1999
dt-pub=199909
dt-online=
en-article=
kn-article=
en-subject=
kn-subject=
en-title=
kn-title=Development of a video-rate range finder using dynamic threshold method for characteristic point detection
en-subtitle=
kn-subtitle=
en-abstract=
kn-abstract=This study develops a video-rate stereo range finding circuit to obtain the depth of objects in a scene by processing video signals (R, G, B, and brightness signals) from binocular CCD cameras. The electronic circuit implements a dynamic threshold method to decrease the affect of signal noise in characteristic point detection, where a video signal from each CCD camera is compared with multiple thresholds, shifting dynamically by feeding back the previous comparison result. Several object depth measurement experiments for simple indoor scenes show that the dynamic threshold method gives high acquisition and correct rates of depth data compared with those by a fixed threshold method for the video signals and a relative method for R, G, and B signals utilized in the authors' previous range finders.
en-copyright=
kn-copyright=

en-aut-name=TanakaYutaka
en-aut-sei=Tanaka
en-aut-mei=Yutaka
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=1
ORCID=

en-aut-name=GofukuAkio
en-aut-sei=Gofuku
en-aut-mei=Akio
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=2
ORCID=

en-aut-name=TakedaNobuo
en-aut-sei=Takeda
en-aut-mei=Nobuo
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=3
ORCID=

en-aut-name=NagaiIsaku
en-aut-sei=Nagai
en-aut-mei=Isaku
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=4
ORCID=

affil-num=1
en-affil=
kn-affil=Department of Systems Engineering, Okayama University

affil-num=2
en-affil=
kn-affil=Department of Systems Engineering, Okayama University

affil-num=3
en-affil=
kn-affil=Graduate School of Engineering, Okayama University

affil-num=4
en-affil=
kn-affil=Department of Systems Engineering, Okayama University
en-keyword=Video-Rate Range Finder
kn-keyword=Video-Rate Range Finder
en-keyword=Stereo Color CCD Camera
kn-keyword=Stereo Color CCD Camera
en-keyword=Autonomous Vehicle
kn-keyword=Autonomous Vehicle
en-keyword=Detection of Characteristic Point
kn-keyword=Detection of Characteristic Point
en-keyword=Real-Time Measurement
kn-keyword=Real-Time Measurement
END

start-ver=1.4
cd-journal=joma
no-vol=
cd-vols=
no-issue=
article-no=
start-page=51
end-page=51
dt-received=
dt-revised=
dt-accepted=
dt-pub-year=1997
dt-pub=199706
dt-online=
en-article=
kn-article=
en-subject=
kn-subject=
en-title=
kn-title=Visual tracking of redundant features
en-subtitle=
kn-subtitle=
en-abstract=
kn-abstract=This paper presents how the control performance of the feature-based visual servo system is improved by utilizing redundant features. Effectiveness of the redundant features is evaluated by the smallest singular value of the image Jacobian which is closely related to the accuracy in the world coordinate system. An LQ control scheme is used to resolve the controllability problem. Usefulness of the redundant features is verified by the real time experiments on a PUMA 560 manipulator.
en-copyright=
kn-copyright=

en-aut-name=HashimotoKoichi
en-aut-sei=Hashimoto
en-aut-mei=Koichi
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=1
ORCID=

en-aut-name=AokiAtsuhito
en-aut-sei=Aoki
en-aut-mei=Atsuhito
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=2
ORCID=

en-aut-name=NoritsuguToshiro
en-aut-sei=Noritsugu
en-aut-mei=Toshiro
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=3
ORCID=

affil-num=1
en-affil=
kn-affil=Department of Mechanical Engineering Okayama University

affil-num=2
en-affil=
kn-affil=Department of Mechanical Engineering Okayama University

affil-num=3
en-affil=
kn-affil=Department of Mechanical Engineering Okayama University
en-keyword=controllability
kn-keyword=controllability
en-keyword=industrial manipulators
kn-keyword=industrial manipulators
en-keyword=linear quadratic control
kn-keyword=linear quadratic control
en-keyword=optical tracking
kn-keyword=optical tracking
en-keyword=path planning
kn-keyword=path planning
en-keyword=real-time systems
kn-keyword=real-time systems
en-keyword=robot vision
kn-keyword=robot vision
en-keyword=sensitivity analysis
kn-keyword=sensitivity analysis
en-keyword=servomechanisms
kn-keyword=servomechanisms
END