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This paper describes a basic concept of a wireless lifeline data gathering project at TAO Hamamatsu Lifeline Research Center. The gathered information creates a GIS database. Using the database the system provides emergency control including active shutoff of lifelines. It also enables rescue personnel to make a restoration plan by predicting damaged portions of the lifelines. For the prediction the system reduces a network into a feasible size and derives a resistance value by linear approximation. Assuming several links damaged, it simulates water flow to make a number of water supply patterns in a prediction database. After a disaster the most fitted pattern is chosen. Implementation of the system reveals that the execution time is reduced by a factor of 80000 and that in 39 days the prediction database including 700 million patterns can be created.

A method of retrieving a temperature-depth profile in biological object from a set of multi-frequency microwave radiometric data has been developed. The method is a combination of model-fitting and Monte Carlo techniques and is capable of estimating a profile and its confidence interval as a function of the depth. We use 2σ -intervals as a measure of the precision of tissue temperature measurements. The method was tested and supported by an experiment in which temperature distributions in a muscle equivalent agar phantom were measured using a 5-band, 1-3.8 GHz radiometer with the brightness temperature resolution of 0.05-0.07 K. A typical result of the experiment showed that 2σ -intervals were 1 K or less for 0 < z < 3 cm, 1.4 K at z = 4 cm, and 3 K at z = 5 cm. A numerical simulation study was made using this technique to assess effects of the selection of measurement frequencies, number of frequency bands, brightness temperature resolution of radiometer and thickness of fat layer on the precision. Resul...

A technique for wireless LAN connection through building concrete wall is proposed. The propagation loss in a 10cm-thick concrete is found at about −8.9dB at 2.4GHz by simulation and experiment. Using a large aperture horn antenna mounted flush on the back of wall, the attenuated signal power is raked over a wide area and reradiated into a space behind the wall via a small second antenna connected back-to-back to the first one in the downlink. It is possible to make the reradiated field in a limited region near the second antenna nearly as strong as that of the wave incident on the wall. An unlicensed small-power relay station based on the IEEE802.11g/b standards is placed in this region to complete the downlink. In the uplink, the signal power from the relay station antenna is picked up by the second antenna and radiated into the space outside the wall. An amplifier of about 13dB gain is required in the uplink in order to make the uplink versus downlink link budgets balanced. The amplifier gain is so set as to comply with the limit set by regulatory agency. The proposed method is analyzed by 3D simulation and its feasibility is supported by experiment.

An experimental three-band (1.5,2.5,3.5+-0.5GHz) radiometer system and a data analysis procedure have been developed for noninvasive measurement of the temperature at various depths in a biological body. Using them, we made temperature measurement experiments on the abdominal region of rabbits. The results of the experiments demonstrate the feasibility of the multifrequency radiometry for this purpose.

A wireless two layer polling system is considered for monitoring and control of city lifelines in disaster situations. An experiment is under way using a 2 GHz/288 kbps radio system for the upper polling layer. Design and performance characteristics obtained to date of a 2 GHz system are reported in this paper.

A wireless asynchronous layer polling system is considered for monitoring and control of city lifelines in disaster situations. In an experimental system, a number of household terminals are connected to a center station via 430 MHz and 2 GHz radio systems. PCs equipped with an RDB are used for communication control and data processing. Results of experiments assisted with simulation indicated that 260k household terminals could be monitored at a repetition interval of 7 minutes.

An assessment is made of the degradation that is caused by a water-filled bolus in the precision of tissue temperature measured noninvasively by a five-band microwave radiometry scheme. The precision is expressed in terms of the confidence interval of tissue temperature estimated from a set of five brightness temperatures measured with an experimental instrument operating at center frequencies of 1.2, 1.8, 2.5, 2.9, and 3.6 GHz, with a 0.4-GHz bandwidth. Results show that degradation due to a bolus having a thickness of about 1 cm is small when it is filled with deionized or distilled water. It is concluded that the use of water-filled bolus is permissible for microwave radiometric measurement. This is of a practical importance when the technique is used in combination with electromagnetic heating for hyperthermic treatment of cancer. >

A wireless data acquisition system is investigated for monitoring and control of city lifeline in disaster situations. This paper describes an experimental system consisting of a 2.1 GHz TDM and 2.4 GHz hybrid TD-CDMA systems and experimental results obtained to date. The system was able to collect the urgent data (2B/terminal) from some 260 k household terminals in 51.7 s and the additional detailed data (32 B/terminal) from some 65 k (=260k/4) household terminals in 2.8 min.

A dedicated data collection system using CDMA technique for fixed stations is considered for monitoring city lifelines. Interference from a wireless LAN operating in the ISM band with the experimental CDMA system was studied. It was shown possible to measure the level of interference power from the wireless LAN using a TD-CDMA technique, while maintaining communication.

An application of CDMA technique to a dedicated data collection system for monitoring and control of city lifelines is considered. This paper describes the system configuration of a 2.4 GHz experimental system in which CDMA is combined with polling technique to access 256 household terminals. Results of preliminary experiments are also presented.

A wireless communication system, especially a wireless LAN (W-LAN) which operates in the ISM (Industrial, Scientific and Medical) band, may be widely used in a home network to transmit data of mobile computing, entertainments, security information, and/or state information of home. The W-LAN system is also prevailing not only in a home or an office, but also in outdoor environments in these days. A TD-CDMA system, which we have developed to collect damage assessment information for a natural disaster, operates in a shared frequency band, 2.4GHz ISM band. This paper describes an influence of the W-LAN on the experimental system, and discusses an interference mitigation method. The experiments show the interference of W-LAN deteriorates the frame error rate (FER) on the order of 10. The proposed mitigation method improves SINR with a closed-loop power control technique of CDMA. The results of the experiments show that the FER recovers at 1×10 or less using the proposed mitigation method, and that the monitoring system is satisfactorily feasible to operate in the vulnerable ISM band.

A method of temperature profiling in biological objects is described. In this method, thermal radiation from the object is measured as the brightness temperature by a multi-channel, topically five, 1 - 4 GHz radiometer via a contact-type, dielectric loaded waveguide antenna with a 15 X 20 mm2 aperture. Coupling between the antenna and the object is analyzed under 1-dimensional approximation. The radiometric data are analyzed by a combined method of model fitting and Monte Carlo techniques to retrieve a temperature profile in tissue and its 2 (sigma) -intervals along the axis of the antenna view field. The method has been tested by numerical simulation and agar phantom experiments to demonstrate its capability of temperature profiling in muscle with 2(sigma)

Fuzzy theory was applied to the rate control of a cardiac pacemaker which uses two parameters, respiratory rate and temperature, as the parameters for rate regulation. Using 25 fuzzy reasoning rules derived from five mongrel dogs, the pacing rates in three animals were calculated and compared with the intrinsic heart rates. It is concluded that the fuzzy method is well suited for the rate determination of a multi-parameter rate-responsive cardiac pacemaker.

A new method using respiratory rate and temperature as the guides for optimal pacing is proposed. A pacemaker was fabricated which senses these two parameters simultaneously. The pacemaker functions by calculating the cardiac rate, which would be derived from the respiratory rate and the blood temperature. The higher of the two rates is adopted as the cardiac pacing rate, i.e., at which stimuli will be delivered. The operation was tested in a mongrel dog with complete atrioventricular block. After the induction of anesthesia, a thermistor temperature probe was inserted into right atrium and a respiratory rate sensor was attached around the chest. After administration of a pyrogenic drug, both respiratory rate and blood temperature increased. The pacing rate was increased from 178 beats/minute(bpm) at 36.4 degrees C, blood temperature, and 26.5 acts/minute(apm), respiratory rate, to 233 bpm at 40.1 degrees C and 40.0 apm. Cardiac output was increased from 2.15 liters/minute(l/pm) at the beginning to 2.50 l/pm at maximum. The transition of the guide from respiratory rate to temperature was observed at about 38 degrees C.

Two pairs of resonance absorptions due to the lowest‐order even 1e and odd 1o surface modes along two axially magnetized polycrystalline yttrium iron garnet YIG rods of several lengths from 3 to 25 mm have been observed in an experiment where the ferrite rods were placed in a TE10 rectangular waveguide and in a cavity coupled with a current loop. One pair is 10e and 10o resonances whose magnetization in each rod precesses in phase over the rod length. The other pair is 11e and 11o resonances due to the half‐wavelength standing waves along the rods. The experimental results are compared with theory. Results of a rudimentary experiment on a magnetically variable directional coupler using these modes are also presented.

An artificial cardiac pacemaker which is sensitive to the temperature of blood in the right atrium has been fabricated. For a temperature change of 20 degrees C the circuit achieves 90% of its final response within a period of 18 s. In the authors' opinion this is satisfactory since changes in blood temperature are generally small. Cardiac output in dogs rose from 2.37 +/- 0.65 to 4.54 +/- 1.15 l/min when the rate was increased from 202.6 beats/min(b.p.m.) at 37.6 degrees C to 231.6 b.p.m. at 41 degrees C. Cardiac output was found, from statistical observation, to be improved at temperatures over 39.6 degrees C.

A microcomputer-based temperature-sensitive cardiac pacemaker system and some preliminary experiments are described. The system consists of a microcomputer, a twin 5 in floppy disk unit, expansion and interface units, a visual display unit and a printer. It senses the blood temperature in the right atrium, determines the pacing rate and supplies the heart with stimulating pulses. System-heart interfacing is performed by the separate pacing and sensing units which communicate with the computer via a peripheral interface IC in an expansion unit. The pacing rate is determined by software, rather than a combination of hardware elements. The temperature response time of the system, from 25 degrees C to 40 degrees C is about 26 s, and this would seem to be satisfactory given that smaller and slower changes in blood temperature are normal.