In this paper, we present the results of an experiment on control in an immersive virtual city using only human brain activities. Applying immersive virtual reality technology, the visual evoked potentials (VEPs), induced by a virtual panorama and two superposed flickering squares, were recorded. The discriminant analysis yielded about 80% of the average classification rate in inferring a user's eye gaze from two directions for three of four subjects. It was possible to demonstrate online control of the virtual scene according to the subject's intent. This suggests that the avatar control is achieved in an immersive virtual environment only via brain signals using visual stimuli.

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Immersive projection displays have recently been able to achieve realistic virtual environments. However, they need expensive realistic interactions with virtual objects. Haptic sensation is especially important in some industrial applications where precise simulation of assembly tasks with virtual objects is required. We propose a human-scale assembly simulator with immersive projection displays and haptic interactions. We developed a string-based 6-DOF and both-hands haptic interface that can be used with immersive projection displays. It can effectively and efficiently assist in assembly tasks with virtual objects in virtual workspaces. We describe the details of the proposed system and discuss our evaluation of its performance.

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Hunting for locations, which is a very important issue in film making, usually involves a great deal of cost in choosing the best site. This paper proposes a novel system that can hunt for the best location in virtual environments. We take images of locations from multiple views whose positions and orientations are measured using GPS, an electronic compass, and two clinometers. The 3D environment for the location can be reconstructed from these images. The director of a film can choose the best location by comparing movies shot in several virtual environments.

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We propose the use of an on-line video synthesis system that makes complementary use of multiple handheld cameras and thus removes occluding objects. We assumed that the same scene is captured with multiple handheld cameras, but an object occludes it. First, we used an ARTag marker to calculate a projection matrix, and then we estimated a homography between two captured images that was based on the projection matrix. We used this homography to transform the planar area into the image seen by the viewer. Finally, we blended the pixel value in accordance with the difference of the pixel values of the captured image and of the warped images at the same position. Doing this means that we remove the occluding object that cannot be approximated as a planar area. Our experimental results prove that this system can be used to remove the occluding object in a dynamic scene.

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A method of real-time recognition of body motion for a virtual dance collaboration system is described. Fourteen feature values are extracted from motion-captured body motion data, and the dimensions of the data are reduced by using principal component analysis (PCA). In the training phase, a dictionary for motion recognition is constructed from training samples of several types of motion. In the recognition phase, feature values obtained from a live dancer's motion data are projected to the subspace obtained by PCA, and the system recognizes the live dancer's motions by comparing them with the motion dictionary. In this paper, we present recognition experiments on seven kinds of basic motions and breakdance motions. The recognition experiment proved that the method was effective for motion recognition. A preliminary experiment in which a live dancer and a virtual dancer collaborate with body motion was also carried out.

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This paper proposes the Orthogonal Frequency Division Multiple Access (OFDMA) transmission scheme with an adaptive slot and bit allocation method which can provide the broadband wireless LAN (WLAN) systems. From the fact that the radio links between different users and a base station experience the independent multi-path fading, this paper proposes a priority-based adaptive slot and bit allocation method in conjunction with an allocation adjustment method. The proposed method can achieve the higher efficient usage of frequency resource than those for the conventional fixed slot assignment with adaptive bit allocation method and the fixed bit assignment with adaptive slot allocation method. This paper presents various computer simulation results to evaluate the proposed method and demonstrates that the proposed method can achieve the higher frequency resource utilization with less computation complexity in the severe frequency selective multi-path fading channels.

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Numerous TV relay stations are required for digital terrestrial broadcasting services in mountainous regions and these are expensive to construct. To reduce their cost, we propose a system that can retransmit UHFband terrestrial digital TV signals (OFDM<Orthogonal Frequency Division Multiplex> signals: nine channels) sent via long-distance (340km) optical-fiber networks. Weverified its exceptional performance through experiments. This system uses an LD direct optical modulator to reduce the construction costs and has a high equivalent C/N of about 40dB and very low distortion, which are traditionally considered to be very difficult to achievewith direct modulation. We attained these by adopting an optimum design to acquire a high C/N and wavelength dispersion compensation to transmit the OFDM signals.

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We investigated what influences the average luminance level (ALL) of displayed images, screen illuminance, and viewers ages had on the preferred luminance of LCDs. Twenty young subjects (mean age: 21.8) and 24 seniors (mean age: 68.9) adjusted the luminance of a 17-inch 1000: 1 LCD monitor to their preferred levels under different experimental conditions. The results indicate that the preferred luminance of LCDs corresponded to the following formula: Lp=k×ALL^α. This is where Lp is the peak white luminance of the LCDs, k is a constant, and ALL is the average luminance level of the displayed images. Here, α is a constant from −0.19 to −0.20 for the seniors and from −0.14 to −0.17 for the young subjects. The influences of age-related changes in vision and ambient lighting on the luminance requirements for LCDs are also discussed. These results can be applied to the design of luminance-control systems for LCDs.

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Conventional super-resolution causes ringings, block-noise and point artifacts. To prevent this, we propose the use of a super-resolution method that is based on segmentation using histgram of image intensity data.

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This paper analyzes success factors from the view point of entrepreneur engineering accomplished by the Hi-Vision plasma display panel (PDP) R&D consortium (abbreviated as the PDP R&D Consortium. 1994-1999) that was established as a conglomerate like association targeting the creation of new technologies. We clarified through assessing outcomes that the optimal timing and the synergy effect between establishing hardware (PDP TVs) and software (Hi-vision programs) in cooperation with the acceleration of Hi-vision diffusion were key factors, which are typically effective in overcoming the death valley laid between a seeds innovation to a needs innovation (stasis between when innovation is introduced and when it delivers yields) . Non-linear concurrent and matrix management was also an effective innovative administrative style.

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