Hiroshi Juzoji

Medical Image Encryption Based on Pixel Arrangement and Random Permutation for Transmission Security

This paper describes the result of our investigation on the utilization pixels arrangement and random permutation to encrypt medical image for transmission security. The objective of this scheme is to obtain a high speed computation process and high security. Among other algorithms such as transform method and traditional method, pixels arrangement and permutation provide simple and quick processes; it particularly does not need any mathematical manipulation. This feature is especially very useful for medical image where the image can be very big. We tested the algorithm using gray-scale images. The scheme shows a good randomness and quick computation process. We closed the paper by discussing the strength and limitation of this for practical for example in telemedicine.

On-Site Investigation of the Early Phase of Bhutan Health Telematics Project

Telemedicine is valuable to many developing countries. International use of telemedicine is widespread. Telemedicine can improve health care in the developing countries by removing time and distance barrier, and optimize the use of limited health services in developing countries. The purpose of this paper is to investigate the current situation of healthcare services and telecommunications infrastructure in Bhutan. It summarizes the experience gained from a previous telemedicine pilot project initiated and implemented by the Telecommunication Development Bureau, International Telecommunication Union (BDT/ITU). It also introduces the priorities of telemedicine development set out by the local health authorities as well as the international organizations. By analyzing the common and most urgent problems in the country, which could be alleviated by using telemedicine, it formulates several recommendations concerning the future development strategy of telemedicine in Bhutan.

Video Endoscopic Database on WWW Linking with ISDN

We report here on a study of creating medical an image library comprised of simple but digitized gastrointestinal video-scope images, which were digitally compressed using MPEG-1 compression, and on the use of this library for clinical and educational applications. We have designed and installed a test-bed database (WWW) for gastrointestinal video-scope images linking with ISDN at 128 Kbps enables Internet access. This paper discusses its development, operation, problems, and educational and clinical use. A test-bed operation of the database was conducted by going on-line on the Internet and through an ISDN circuit (point-to-point connection) at a speed of 128 Kbps. This dynamic image database proved to be effective in diagnostic imaging for endoscopic diagnosis and treatment. It also proved to be useful for improving the clinical levels of geographically isolated physicians.

A study of increasing the speed of the independent component analysis (IA) using wavelet technique

Independent component analysis (ICA) is a multivariate data analysis tool. The basic principle of ICA is the assumption of independency of the source data. On the separation of the data source, ICA algorithm searches for a demixing matrix that will maximize the independency. This searching process is mostly done in iterative way and involving high order statistics. This process is time consuming. For a certain application, such as speech, where the source signal has its power at the lower frequency, we can reduce the data length by removing the high frequency component. Wavelet decomposition is a popular method for this purpose. In this paper, we propose the data reduction using wavelet as a preprocessing of ICA to speed up the ICA computation. We investigate Haar, Daubechies 2, Daubechies 3, and Daubechies 4 wavelet as the wavelet analysis. We further investigate the computation time as the function of level of decomposition of the wavelet. In this study, we found that Haar wavelet at third level of decomposition gave the biggest advantage of computation speed, which is about 40-50%.

Satellite communications for supporting medical care in the aftermath of disasters

At present, mobile phones are not a useful tool for medical control during a disaster. We have estimated the number of satellite channels that would be needed for telemedicine in a major disaster using the Erlang B equation. This indicated that 29 satellite channels would be sufficient for the operation of a telemedicine system for hospital-to-hospital communications during a major disaster in Japan. Governments at local and national levels in Japan, as well as private organizations, require an independent satellite telecommunication infrastructure to deal with the aftermath of disasters.

Elevation Angle of Quasi-Zenith Satellite to Exceed Limit of Satellite Visibility of Space Diversity which consisted of Two Geostationary Satellites

The paramedic in the moving ambulance sends the moving picture data to the doctor in the hospital via the communications satellite. However, when an ambulance runs inside a city, a radio wave to the communication satellite is blocked and as a result the moving picture data sometimes freeze. A value of the satellite visibility by the space diversity which consists of two geostationary satellites was acquired by simulation based on the hemispherical urban space data measured by a fish-eye camera in each city of Japan. From these simulation results, it was found that there was a limit in the satellite visibility by the space diversity. It is known that the satellite visibility is more improved by the quasi-zenith satellite. The elevation angle condition of the quasi-zenith satellite which exceeds the limit of the satellite visibility of two geostationary satellites was acquired. This elevation angle was compared between each city of Japan. It became clear that more than 68 deg of an elevation angle of the quasi- zenith satellite is necessary to exceed the limit of satellite visibility of two geostationary satellites.

A study of heartbeat sound separation using independent component analysis technique

Physician often infers the patients heart problem by listening to heartbeat sound. Such technique is well known as auscultation. The doctors auscultation skill was gain after he or she experiencing a lot of cases of heart diseases and heartbeat sounds. There is a need of computer-aided equipment to analyze heartbeat sound especially for young doctors to gain a quick learning process. For this purpose, we need accurate and dependable equipment for heartbeat analysis. To improve the heartbeat analysis, we investigate the possibility of the heartbeat sound analysis, especially the separation and localization of heartbeat signal, using independent component analysis technique. The separation or localization of heartbeat signal using independent component analysis is made possible by putting several probe at appropriate places in body. Our aim is to separate two major beat sequences, which are referred as S1 and S2. The S1 beat is due to the closure of mitral-tricuspid valve and the S2 beat is due to the closure of aortic-pulmonary valve. Since the pairs of mitral-tricuspid and aortic-pulmonary valves are physically separated and can be viewed as independent sources, we can treat the beats produced by them as independent components. The FastICA algorithm was used in this study, and we do experience with a healthy 29 year-old man. The experiment showed a promising result. A refinement in the scheme of experiment, especially technique to reduce signal saturation and noise during data acquisition, will lead us to scheme for the real application.

Investigation and Analysis of a Reported Incident Resulting in an Actual Airline Hijacking due to a Fanatical and Engrossed VR State

We begin this report by defining Chronic Alternate-World Disorder (CAWD) as a symptomatic behavior in which a person becomes fanatically engrossed in a virtual-reality (VR) world to the extent that he or she can no longer distinguish between the actual world and virtual reality. We then report on our investigation and provide an analysis and discussion of what we believe to be a case of CAWD. The case in question involves a perpetrator who hijacked a jumbo jetliner in order to fly the airplane on his own, after developing CAWD from the use of light-simulator software. Psychiatrists and physicians specializing in VR-related disorders have analyzed the cases psychological, social, and technical background based on previously disclosed information. We believe symptomatic cases of CAWD will increase as VR spreads throughout our society. In view of this, our objective is to propose precautionary and preventive measures for providers of VR systems for patients with schizophrenia or personality disorders, from psychiatric and sociological perspectives.

Telemedicine in the land of thunder dragon - East Bhutan tele-ECG project

The technology of telemedicine and e-health has now reached the stage awaiting wide scale application with promising potential benefits to many of the developing countries scourged persistently by the plague of resource constraints and harsh natural topography. The transmission of medical images from a remote understaffed health center to any bigger hospital for specialized and enhanced diagnosis is now a possibility through the use of Internet protocol. We apart from looking at the state of telemedicine and its variety deals as a case study in the possibility of introducing teleECG over IP which can go a long way in enhancing the diagnosis of cardiovascular diseases in the rural areas of Trashiyangtse and Lhuntse in East Bhutan.

The final report of the project ‘AMINE’ The Asia Pacific Medical Information Network using with ETS-V

Volunteer groups led by the Tokai University School of Medicine and the Telemedicine Society of Japan (a Non-Governmental Organization) worked from 1992 to 1996 to successfully develop a medical network spanning the Asia Pacific region using the ETS-V Satellite. The effort was part of the Partners project, sponsored by the Ministry of Posts and Telecommunications (MPT) and the National Space Development Agency of Japan. From 25 ground stations, links to the telemedical network were installed at medical institutions at no cost. The stations included five in Papua New Guinea, five in Thailand, four in Cambodia, four in Fiji, one in China, and six in Japan. Designed exclusively for medical applications, the network was operated free of charge for users at these sites. While the 16-kHz FM-based (Frequency Modulation-based) network limited applications to the transmission of color still images and audio and packet networking, the project still achieved impressive results. The network allowed liberal and independent use of international communications, local communications, teleconferences, and teleconsultations, without requiring a hub station.