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[Author] Kazuaki KONDO(9hit)

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  • FOREWORD Open Access

    Kazuaki KONDO  

     
    FOREWORD

      Vol:
    E107-D No:3
      Page(s):
    331-331
  • Investigation on e-Learning Status Estimation for New Learners — Classifier Selection on Representative Sample Selection

    Siyang YU  Kazuaki KONDO  Yuichi NAKAMURA  Takayuki NAKAJIMA  Masatake DANTSUJI  

     
    LETTER-Educational Technology

      Pubricized:
    2020/01/20
      Vol:
    E103-D No:4
      Page(s):
    905-909

    This article introduces our investigation on learning state estimation in e-learning on the condition that visual observation and recording of a learner's behaviors is possible. In this research, we examined methods of adaptation for a new learner for whom a small number of ground truth data can be obtained.

  • Design and Performance Analysis of a Skin-Stretcher Device for Urging Head Rotation

    Takahide ITO  Yuichi NAKAMURA  Kazuaki KONDO  Espen KNOOP  Jonathan ROSSITER  

     
    PAPER-Human-computer Interaction

      Pubricized:
    2020/08/03
      Vol:
    E103-D No:11
      Page(s):
    2314-2322

    This paper introduces a novel skin-stretcher device for gently urging head rotation. The device pulls and/or pushes the skin on the user's neck by using servo motors. The user is induced to rotate his/her head based on the sensation caused by the local stretching of skin. This mechanism informs the user when and how much the head rotation is requested; however it does not force head rotation, i.e., it allows the user to ignore the stimuli and to maintain voluntary movements. We implemented a prototype device and analyzed the performance of the skin stretcher as a human-in-the-loop system. Experimental results define its fundamental characteristics, such as input-output gain, settling time, and other dynamic behaviors. Features are analyzed, for example, input-output gain is stable within the same installation condition, but various between users.

  • Visual Emphasis of Lip Protrusion for Pronunciation Learning

    Siyang YU  Kazuaki KONDO  Yuichi NAKAMURA  Takayuki NAKAJIMA  Hiroaki NANJO  Masatake DANTSUJI  

     
    PAPER-Educational Technology

      Pubricized:
    2018/10/22
      Vol:
    E102-D No:1
      Page(s):
    156-164

    Pronunciation is a fundamental factor in speaking and listening. However, instructions for important articulation have not been sufficiently provided in conventional computer-assisted language learning (CALL) systems. One typical case is the articulation of rounded vowels. Although lip protrusion is essential for their correct pronunciation, the perception of lip protrusion is often difficult for beginners. To tackle this issue, we propose an innovative method that will provide a comprehensive visual explanation for articulation. Lip movements are three-dimensionally measured, and face images or videos are pseudocoloured on the basis of the movements. The coloured regions represent the lip protrusion of rounded vowels. To verify the learning effect of the proposed method, we conducted experiments with Japanese undergraduates in Chinese classes. The results showed that our method has advantages over conventional video materials.

  • Non-Linear Distance Filter for Modeling Effect of a Large Pointer Used in a Gesture-Based Pointing Interface

    Kazuaki KONDO  Takuto FUJIWARA  Yuichi NAKAMURA  

     
    PAPER-Human-computer Interaction

      Pubricized:
    2020/08/03
      Vol:
    E103-D No:11
      Page(s):
    2302-2313

    When using a gesture-based interface for pointing to targets on a wide screen, displaying a large pointer instead of a typical spot pattern reduces disturbance caused by measurement errors of user's pointing posture. However, it remains unclear why a large pointer helps facilitate easy pointing. To examine this issue, in this study we propose a mathematical model that formulates human pointing motions affected by a large pointer. Our idea is to describe the effect of the large pointer as human visual perception, because the user will perceive the pointer-target distance as being shorter than it actually is. We embedded this scheme, referred to as non-linear distance filter (NDF), into a typical feedback loop model designed to formulate human pointing motions. We also proposed a method to estimate NDF mapping from pointing trajectories, and used it to investigate the applicability of the model under three typical disturbance patterns: small vibration, smooth shift, and step signal. Experimental results demonstrated that the proposed NDF-based model could accurately reproduced actual pointing trajectories, achieving high similarity values of 0.89, 0.97, and 0.91 for the three respective disturbance patterns. The results indicate the applicability of the proposed method. In addition, we confirmed that the obtained NDF mappings suggested rationales for why a large pointer helps facilitate easy pointing.

  • Integration of Experts' and Beginners' Machine Operation Experiences to Obtain a Detailed Task Model

    Longfei CHEN  Yuichi NAKAMURA  Kazuaki KONDO  Dima DAMEN  Walterio MAYOL-CUEVAS  

     
    PAPER-Human-computer Interaction

      Pubricized:
    2020/10/02
      Vol:
    E104-D No:1
      Page(s):
    152-161

    We propose a novel framework for integrating beginners' machine operational experiences with those of experts' to obtain a detailed task model. Beginners can provide valuable information for operation guidance and task design; for example, from the operations that are easy or difficult for them, the mistakes they make, and the strategy they tend to choose. However, beginners' experiences often vary widely and are difficult to integrate directly. Thus, we consider an operational experience as a sequence of hand-machine interactions at hotspots. Then, a few experts' experiences and a sufficient number of beginners' experiences are unified using two aggregation steps that align and integrate sequences of interactions. We applied our method to more than 40 experiences of a sewing task. The results demonstrate good potential for modeling and obtaining important properties of the task.

  • Learning State Recognition in Self-Paced E-Learning

    Siyang YU  Kazuaki KONDO  Yuichi NAKAMURA  Takayuki NAKAJIMA  Masatake DANTSUJI  

     
    PAPER-Educational Technology

      Pubricized:
    2016/11/21
      Vol:
    E100-D No:2
      Page(s):
    340-349

    Self-paced e-learning provides much more freedom in time and locale than traditional education as well as diversity of learning contents and learning media and tools. However, its limitations must not be ignored. Lack of information on learners' states is a serious issue that can lead to severe problems, such as low learning efficiency, motivation loss, and even dropping out of e-learning. We have designed a novel e-learning support system that can visually observe learners' non-verbal behaviors and estimate their learning states and that can be easily integrated into practical e-learning environments. Three pairs of internal states closely related to learning performance, concentration-distraction, difficulty-ease, and interest-boredom, were selected as targets of recognition. In addition, we investigated the practical problem of estimating the learning states of a new learner whose characteristics are not known in advance. Experimental results show the potential of our system.

  • Hotspot Modeling of Hand-Machine Interaction Experiences from a Head-Mounted RGB-D Camera

    Longfei CHEN  Yuichi NAKAMURA  Kazuaki KONDO  Walterio MAYOL-CUEVAS  

     
    PAPER-Human-computer Interaction

      Pubricized:
    2018/11/12
      Vol:
    E102-D No:2
      Page(s):
    319-330

    This paper presents an approach to analyze and model tasks of machines being operated. The executions of the tasks were captured through egocentric vision. Each task was decomposed into a sequence of physical hand-machine interactions, which are described with touch-based hotspots and interaction patterns. Modeling the tasks was achieved by integrating the experiences of multiple experts and using a hidden Markov model (HMM). Here, we present the results of more than 70 recorded egocentric experiences of the operation of a sewing machine. Our methods show good potential for the detection of hand-machine interactions and modeling of machine operation tasks.

  • Feedback Control Model of a Gesture-Based Pointing Interface for a Large Display

    Kazuaki KONDO  Genki MIZUNO  Yuichi NAKAMURA  

     
    PAPER-Human-computer Interaction

      Pubricized:
    2018/04/04
      Vol:
    E101-D No:7
      Page(s):
    1894-1905

    This study proposes a mathematical model of a gesture-based pointing interface system for simulating pointing behaviors in various situations. We assume an interaction between a pointing interface and a user as a human-in-the-loop system and describe it using feedback control theory. The model is formulated as a hybrid of a target value follow-up component and a disturbance compensation one. These are induced from the same feedback loop but with different parameter sets to describe human pointing characteristics well. The two optimal parameter sets were determined individually to represent actual pointing behaviors accurately for step input signals and random walk disturbance sequences, respectively. The calibrated model is used to simulate pointing behaviors for arbitrary input signals expected in practical situations. Through experimental evaluations, we quantitatively analyzed the performance of the proposed hybrid model regarding how accurately it can simulate actual pointing behaviors and also discuss the advantage regarding the basic non-hybrid model. Model refinements for further accuracy are also suggested based on the evaluation results.