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We made an attempt to express a complaint of sleep disturbance by a self-rating scale of radar chart mode. The questionnaire for sleep disturbance is made up of eight items. Each item was scored from grade 1 to 4. The score of each item was projected to the MY radar chart, designed by us. It is noted that this method is useful in following the effect of hypnotics on sleep disturbance.
We report the first radar soundings of the ionosphere of Mars with the MARSIS (Mars Advanced Radar for Subsurface and Ionosphere Sounding) instrument on board the orbiting Mars Express spacecraft. Several types of ionospheric echoes are observed, ranging from vertical echoes caused by specular reflection from the horizontally stratified ionosphere to a wide variety of oblique and diffuse echoes. The oblique echoes are believed to arise mainly from ionospheric structures associated with the complex crustal magnetic fields of Mars. Echoes at the electron plasma frequency and the cyclotron period also provide measurements of the local electron density and magnetic field strength.
Observations obtained with a mobile pencil-beam Doppler radar revealed many previously unresolved structures within tornadic storms and tornadoes and helped verify various aspects of conceptual models. Radar data from the parent circulations indicate the existence of spiral reflectivity bands, intense radial wind shear zones, and multiple larger-scale velocity maxima. Tornado structures observed include debris shields, clear axial (eye) regions, multiple reflectivity bands surrounding the center of the eye, and occasional reflectivity protrusions into the eye. Velocity and reflectivity data from tornado-scale circulations show evidence of axial downdrafts.
Radar observations of comet Hyakutake (C/1996 B2) made at the Goldstone Deep Space Communications Complex in California have detected echoes from the nucleus and from large grains in the inner coma. The nucleus of this bright comet was estimated to be only 2 to 3 kilometers in diameter. Models of the coma echo indicate backscatter from porous, centimeter-size grains ejected anisotropically at velocities of tens of meters per second. The radar observations suggest that a comet's activity may be a poor indicator of its size and provide evidence that large grains constitute an important component of the mass loss from a typical active comet.
Spaceborne radar interferometric delay measurements were used to infer high-resolution maps of integrated atmospheric water vapor, which can be readily related to meteorological phenomena. Maps of the water vapor distribution associated with a precipitating cloud, a partly precipitating cold front, and horizontal convective rolls reveal quantitative measures that are not observed with conventional methods, and suggest that such radar observations can be used for forecasting and to study atmospheric dynamics.
Coherent laser radar systems in the mid-IR wavelength region can have advantages in low-altitude environment because they are less sensitive to scattering, turbulence, and humidity, which can affect shorter- or longer-wavelength system. We describe a coherent laser radar at 3.6 microm based on a single-frequency optical parametric oscillator and demonstrate the system over short ranges outdoors. The system was used to make micro-Doppler measurements from idling trucks that were processed to give surface vibration spectra.
An automated technique for adaptive radar polarimetric pattern classification is described. The approach is based on a genetic algorithm that uses a probabilistic pattern separation distance function and searches for those transmit and receive states of polarization sensing angles that optimize this function. Seven pattern separation distance functions--the Rayleigh quotient, the Bhattacharyya, divergence, Kolmogorov, Matusta, Kullback-Leibler distances, and the Bayesian probability of error--are used on real, fully polarimetric synthetic aperture radar target signatures. Each of these signatures is represented as functions of transmit and receive polarization ellipticity angles and the angle of polarization ellipse. The results indicate that, based on the majority of the distance functions used, there is a unique set of state of polarization angles whose use will lead to improved classification performance.
A Diagnostic Radar Chart method was devised for use in the general assessment of the toxicity of drugs on the basis of visual patterns in toxicity studies. Its usefulness was evaluated on the findings of 32 laboratory items in 3 groups of animal models with experimental pathological conditions. The chart was found to facilitate intuitive discrimination among three types of pathological animal models, evaluation of sexual differences and evaluation of individual differences among the animals for each item. Therefore, if patterns are constructed on the Diagnostic Radar Chart for each of the drugs usable for preparing animal models with typical experimental pathological conditions, the chart is thought to be useful for evaluation or identification of the toxicity of an unknown drug.
The chirp radar-type microwave computed tomograph (CT) measures the temperature change in a human body noninvasively. The paper examines its feasibility. A chirp pulse signal between 1 and 2 GHz is radiated from the transmitting antenna to the phantom. The transmitted waves are detected by the receiving antenna, which is placed on the opposite side of the object, and the beat signal between the incident wave and the transmitted wave is produced by the mixer. By spectral analysis of the beat signal, only those signals transmitted on the straight line between the transmitting antenna and the receiving antenna are discriminated from multipath signals. The microwave tomogram can therefore be reconstructed easily using the conventional algorithms for an X-ray CT image. The microwave CT can use the chirp signal to remove the influence of multipath signals caused by diffraction and reflection. The imaging of dielectric materials with complicated structures is thus possible. The experimental results using phantoms show that the spatial resolution of this microwave CT is about 10 mm and that a two-dimensional distribution of temperature change can be measured.
Doppler shift radar was used to monitor circadian activity patterns in the rat and to study the behavioural effects of p-chloroamphetamine and d-amphetamine. Activity was classified in two ways:-(a) slow (non-locomotory) and high (locomotory) speed movements. (b) the number of starts of activity, within either the slow or high speed zones of activity during a pre-set time. p-Choloramphetamine (5 mg/kg) produced a biphasic activity response; an initial increase in continuous non-locomotory activity followed by a longer lasting increase in exploratory locomotion containing regular starts of activity. d-Amphetamine (2.5 mg/kg) produced an increase in both non-locomotory and locomotory movements but a marked reduction in starts of activity (i.e. continuous non-exploratory activity). The combination of information on the amount and pattern (starts) of activity allows a more detailed analysis of the effects of drugs on activity to be made than with existing automated methods.
Two experiments were concluded in which target detection performance was measured for male and female subjects engaged in a simulated radar monitoring task. In the first, 20 subjects performed for 2 h; in the second, 28 subjects for 1 h. Adrenaline excretion rate was significantly correlated with performance efficiency in both cases. Task duration and subject sex had no effect upon that correlation. The results of the two experiments were combined to show a general adrenaline/performance relationship.
In an evaluation study, the effects of targeted speed enforcement on speed and road accidents were assessed. Enforcement was predominantly carried out by means of mobile radar and focused on rural non-motorway roads. Information and publicity supported the enforcement activities. The evaluation covered a period of 5 years of enforcement. The speed data of these 5 years and the year preceding the enforcement project showed a significant decrease in mean speed and the percentage speed limit violators over time. The largest decrease was found in the first year of the enforcement project and in the fourth year of the project, when the enforcement effort was further intensified. There were similar decreases in speeding at both the enforced roads and at the nearby comparison roads that were not subjected to the targeted speed enforcement project, which may be explained by spillover effects. The best estimate for the safety effect of the enforcement project is a reduction of 21% in both the number of injury accidents and the number of serious casualties. This was based on comparison between the number of accidents/casualties during the enforcement project (5 years) and and the 8 preceding years on the enforced roads and at all other roads outside urban areas in the same region.
Cross-borehole ground penetrating radar (XBGPR) is used in monitoring a long-term vadose zone infiltration experiment at a test site in Socorro, NM in order to examine contaminant transport in the vadose zone. XBGPR attenuation tomography is conducted in order to test the ability of using images of electromagnetic attenuation for hydrogeologic investigations. The results of four pre-infiltration attenuation inversions shows standard deviations below 0.1 Np/m, and demonstrate the consistency of the XBGPR tomography technique for making time-lapse observations. Correlation to the core records indicates that XBGPR attenuation tomograms provide high-resolution images of clay distribution in the vadose zone. Water infiltration at the ground surface was initiated in February 1999 at a constant rate of 2.7 cm/day, and continued at this rate throughout the data collection experiment. Time-lapse attenuation tomograms show that attenuation increases by approximately 0.3 Np/m during the water infiltration, and indicate a snowplow effect may be occurring where salts are dissolved by the water and concentrated at the front of the plume. Seasonal temperature changes may also cause changes in electromagnetic attenuation images, and masking the evidence of water infiltration. Thus caution must be taken when using time-lapse attenuation images to interpret the movement of a water plume during a long-term experiment as temperature changes.
Cognitive ethology focuses on the study of animals under natural conditions to reveal ecologically adapted modes of learning. But biologists can more easily study what an animal learns than how it learns. For example, honeybees take repeated 'orientation' flights before becoming foragers at about three weeks of age. These flights are a prerequisite for successful homing. Little is known about these flights because orienting bees rapidly fly out of the range of human observation. Using harmonic radar, we show for the first time a striking ontogeny to honeybee orientation flights. With increased experience, bees hold trip duration constant but fly faster, so later trips cover a larger area than earlier trips. In addition, each flight is typically restricted to a narrow sector around the hive. Orientation flights provide honeybees with repeated opportunities to view the hive and landscape features from different viewpoints, suggesting that bees learn the local landscape in a progressive fashion. We also show that these changes in orientation flight are related to the number of previous flights taken instead of chronological age, suggesting a learning process adapted to changes in weather conditions, flower availability and the needs of bee colonies.
The authors have reported on 5 young patients who had brain tumors that appeared within 10 yr of initial occupational exposures to radar. Four of the patients were less than 30 yr of age when the diagnoses were initially made. Brief induction periods that follow high exposures in individual sentinel patients are a recognized indicator of impending group risk, and these periods call attention to the need for precautionary measures. Similarly, reports of short induction periods for brain cancer on the side of the head in which there has been prior use of cell phones may also indicate increased risk.
The northward migration of Helicoverpa armigera (Hübner) and other moths in early summer was observed with radar in 2001 and 2002 at Langfang, Hebei province, China. Migratory flights typically occurred at heights up to 1.2 km above ground level (AGL), and high density layer concentrations frequently formed at 200-300 m AGL. Adult moths of local populations took off at dusk and ceased flight approximately 0.5 h before sunrise with area density peaking approximately 35 min after dusk. A strong dumb-bell pattern of echoes on the plan position indicator screen, indicating collective orientation of the targets, was evident in 2001, when targets were typically moving toward the northeast and when layering was associated with a temperature inversion and maximum wind speed. By contrast, there was no notable dumb-bell pattern in 2002, when targets were moving toward the northwest. However, orientations calculated from target and wind velocities showed that downwind common orientation also was occurring in 2002 and that the direction varied with the wind direction. The probable sources of the H. armigera observed at Langfang were deduced to be Henan province in 2001 and Shandong province in 2002, and the destination regions were Liaoning and Inner Mongolia.
The effects of occupational experience with microwave radiation (radar) on the health of US enlisted Naval personnel were studied in cohorts of approximately 20,000 men with maximum opportunity for exposure (electronic equipment repair) and 208000 with minimum potential for exposure (equipment operation) who served during the Korean War period. Potential exposure was assessed in terms of occupational duties, length of time in occupation and power of equipment at the time of exposure. Actual exposure to members of each cohort could not be established. Mortality by cause of death, hospitalization during military service, later hospitalization in Veterans Administration (VA) facilities, and VA disability compensation were the health indexes studied, largely through the use of automated record systems. No adverse effects were detected in these indexes that could be attributed to potential microwave radiation exposures during the period 1950-1954. Functional and behavioral changes and ill-defined conditions, such as have been reported as microwave effects, could not be investigated in this study but subgroups of the living study population can be identified for expanded follow-up.
Seventeen radar mechanics and engineers and 12 unexposed referents were examined, using extensive neurological, psychometric and neuropsychiatric techniques to determine whether there were any indications of central nervous system effects of microwave exposure. Pathological neurological findings were not more common in the exposed group than among the referents. In addition, the psychometric tests and the psychiatric rating scales did not reveal any statistically significant adverse effects of microwave exposure. The frequency of the occurrence of an increased protein band with an isoelectric point of 4.5 in the cerebrospinal fluid was higher among the men exposed to microwaves than among the referents. The nature and clinical significance of this or these proteins are still unclear. The time derivative of the magnetic flux density close to some of the transmitter units was surprisingly high (up to 350 T s-1).