Norihisa Segawa

Design and Implementation of Synchronized Audio-to-Audio Steganography Scheme

Steganography technologies developed to protect multimedia content make great progress in recent years. This paper proposes a synchronized steganography system for acoustic data. The synchronous aspect means that the secret data is to be recorded and steganographically embedded and subsequently sent or broadcasted to multiple receivers. However, only the trusted receiver can extract the secret data using a secret key shared with the sender in advance. Acoustic data is transmitted through socket communication. Main processes in this scheme include PCM Setting, Embedding Process, and Robustness Analysis. Algorithm, mainly focuses on masking calculation towards cover bit stream in each sampling point makes it possible that secret bit stream can be interspersed into significant bit locations in cover without drawing suspicion even though some certain performance degradation is caused.

Information hiding with a handwritten message in vector-drawing codes

The Internet has been evolving exponentially, and various types of communication systems for computer supported cooperative work (CSCW) are available throughout networks. Some of those systems provide handwriting functions, and handwritten messages are often used for authentication. In other communication systems, however, one needs information hiding. A requirement of a communication system is to provide a subliminal channel for secret communications. This paper presents new algorithms for information hiding with a handwritten message which is encoded with vector drawing.

A message board on WWW for on-door communication

This paper reports on our trial of the development of a message board system on the World-Wide Web (WWW), which supports communications between a receiver and anonymous senders. We call this type of system an “on-door” communication board, and implemented a prototype based on our experience of the operation of such a board on the door of a room in a graduate student hall of residence.

The proposal of the digital plethysmograph using a sensor network

We develop a new digital plethysmograph using a sensor network. We can utilize autonomic indices for instance heart rate and heart rate variability from the plethysmogram recording. It makes possible to evaluate users physiological state easily and on real time.

A prototype system of the MAD-SS wide area sensor network using a weather balloon

In this study, we conducted long-distance radio propagation experiments at 1mW/145 MHz to realize low-power long-distance communication for wildlife research and disaster prevention telemetry [1]. We successfully realized long-distance communications from a weather balloon (elevation: ~14,000 m) with 1 mW radio power. Furthermore, we demonstrated that our method can achieve such long-distance communication at 10 BPS/1mW with battery cell operation in the SSB mode and that the SNR in the SSB bandwidth is better than -10 dB.

Poster: a construction of a long distance communication sensor network node using Arduino and Mad-SS shield

In this paper, we describe the construction of a long distance communication sensor network node for Arduino. We develop a Mad-SS Shield prototype system, which succeeds in about 5-km transmission with a 1 mW output.

A marine experiment of a long distance communication sensor network -MAD-SS-

We conducted long distance radio propagation experiments at 1-10mW/145MHz, to realize a low-power long-distance communication for wildlife research and disaster prevention telemetry. In this paper, we describe that we succeeded in long distance communications, from a ferryboat to the top of Mt. Asugiyama (elevation: 501m, distance: 15km) in Kure, Hiroshima, Japan, in the verification test of our method using 3W radio power. We found out that our method has sufficient capability to achieve such a long distance communication at 10BPS/10mW in battery cell operation on a marine, if we use SSB mode and the SNR in SSB bandwidth is better than -10dB.

Proposal for a sensor network application development with ActionScript

In recent years, the research of sensor networks has advanced. They are anticipated for use in a wide variety of fields such as traceability systems of products, environmental morning, health care, etc. However, developers must develop applications to work in a sensor node and applications to make the sensor data visible. Therefore the knowledge that is necessary for development and the acquisition of the language will take time to develop. As described in this paper, we propose a development environment for sensor network application development. The environgment will be useful even by web programmers and a designers.

A real-time sensor network visualization system using KVS: Kyoto visualization system

We report the system that collects the data from the sensor network and visualizes the data on real time by three dimensions on a computer. It becomes possible for this system to make a user make the measurement data on space intuitive.

Poster Abstract: Multiple Door Opening/Closing Detection System Using Infrasound Sensor

Our research group is currently focused on research and development of Internet of Things-based robust emergency and disaster prevention systems to transmit tsunami information retrieved from infrasound sensors. To constantly test the effective sensor operation, it is necessary generate infrasound. Therefore, we considered the infrasound generated when opening and closing doors in this study, and used one sensor to detect the state variation of multiple doors. We constructed and verified the detection system for various doors.