Search

An accurate estimation of the distance between the robot and the respective object is highly demanded in the robotics field. Proximity sensors such as laser scanners and sonar are mainly used to calculate distance. This research paper proposes a pair of Web cameras for distance measurement, by using stereo vision. A comparison of the accuracy of the calculations was done for 3 zones: left, right and center. This separation allows identifying possible distortion or camera failure at the edge of the image. As a result of the research, an accuracy of 71.939% was achieved. Also defined parameters which can help to improve the precision of object coordinates in 3D.

An analysis is made of the sound produced by vorticity generated as high pressure fluid is forced through an aperture in the wall of a duct in the presence of an exterior baffle plate. The aperture typically behaves as a ‘pressure release’ opening when the flow is ideal and irrotational, corresponding to the traditional interpretation of the action of a finger hole of a woodwind instrument, although theoretical predictions that neglect vorticity are irrelevant in practice except at very high frequencies. The theory of vortex sound is applied to derive an approximate nonlinear equation for the volume flux through the baffled aperture that generalises Cummings's empirical equation for a jet exhausting through a fully open orifice in a large wall. The equation takes account of the impingement of the jet on the baffle and of the nonlinear ‘inertial blocking’ of the aperture flow. Application is made to the problem of compression wave generation by a high-speed train entering a tunnel fitted with an entrance hood whose windows are partially ‘closed’ by the presence of a side-wall of a railway cutting or embankment. Theoretical predictions are found to be in good agreement with measurements made at model scale at train speeds ∼ 300 – 400 km / h .

Experimental studies on bottled neutrons have been carried out using a supermirror turbine facility and are compared with the results of numerical simulations. The gravity effects for 1 m elevation and fall with guides are observed. Measured exhausting and storage lifetimes agree with the numerical results, which indicate the collision loss probability of about 10 −4 to be expected in the bottle studied.

Generation of the compression wave by a train entering a tunnel is investigated by model experiments. In the model experiments, the train and the tunnel are represented by an axisymmetric model, a three-dimensional mirror image model and a three-dimensional model. The experimental results indicate that the effect of the three-dimensionality of the train nose shape is approximately 2 % for the pressure gradient of the compression wavefront when the train nose is streamlined, hence without large flow separation around the train nose. Furthermore, the relationship between the pressure gradient of the compression wavefront and the train position in a cross-section at the tunnel portal is clarified.

This paper discusses an selective ant colony optimization algorithm. The proposed algorithm introduces the exclusive mechanism which utilizes the static evaluation of ACO. It reduces not only the calculation time, but also the total number of steps for the selection, while keeping the quality of solutions. Simulation results using benchmark data prove the validity of the proposed algorithm.

The computer-controlled instrument for the magnetic measurement of the SKS sector-type superconductivity magnet at KEK is described. The sector-shaped field is measured to a precision on the order of 10/sup -4/ of the maximum field by assemblies of Hall elements. The authors discuss the field measuring instrument, the concept of how to control the instrument and read data, and preliminary results on field mapping. >

A sector-type superconducting spectrometer magnet, called SKS, for nuclear physics experiments in the 1-GeV/c region has been constructed and installed at KEK. It has a maximum central magnetic field of 3 T in a magnet gap of 50 cm, required by properties of high resolution and large acceptance. From another requirement to be movable around a target at a cold state, a flexible transfer line is adopted. The maximum rated current of 500 A is selected to make the heat losses as as small as possible. A small refrigerator is used for thermal insulations at 80 and 20 K in combination with a medium one at 4 K. >

In order to clarify the pathogenesis of hypercalcemia in multiple myeloma, we measured plasma levels of parathyroid hormone related peptide (PTHrP), tumor necrosis factor alpha (TNF-alpha), tumor necrosis factor beta (TNF-beta), intact PTH and, serum 1,25-dihydroxyvitamin D in fifteen patients of multiple myeloma. We also measured serum levels of inorganic phosphorus (iP) and alkalinephosphatase activity (ALP). No significant differences in iP (3.2 +/- 0.4 vs. 4.0 +/- 2.2 mg/dl), ALP (150 +/- 28 vs. 335 +/- 305 IU/l) 1,25(OH)2 D (31.5 +/- 17.0 vs. 23.3 +/- 11.2 pg/ml) or TNF-alpha (7.8 +/- 2.1 vs. 8.0 +/- 2.0 pg/ml) were observed between normocalcemic and hypercalcemic patients. Plasma iPTH levels in hypercalcemic patients were significantly lower than those in normocalcemic patients (28.5 +/- 9.4 vs. 16.3 +/- 5.6 pg/ml, p = 0.01). Plasma levels of TNF-beta were less than 15.6 pg/ml in all subjects. On the other hand, the frequency of patients with abnormally high plasma levels of PTHrP was significantly greater (2/9 for normocalcemia vs 5/6 for hypercalcemia, chi 2 = 5.20, p = 0.02) in patients with hypercalcemia than in normocalcemic patients. Furthermore, a significant positive relationship between plasma PTHrP levels and corrected serum calcium levels (cCa) was observed using Spearman's correlation analysis by rank in fifteen myeloma cases (rs = 0.66, p = 0.013). These results suggest that PTHrP might be involved in the elevation of serum calcium levels in hypercalcemic myeloma patients. However, a few cases exhibit normocalcemia despite elevated plasma PTHrP levels or hypercalcemia without high plasma PTHrP levels. Therefore, further studies are necessary to elucidate the pathogenesis of hypercalcemia in multiple myeloma.

Although urban parks provide various benefits, the area and number of such parks in Nagasaki City is below the national standard. This study aimed at identification of areas lacking urban parks and selection of their location in Nagasaki City by using GIS (Geographic Information Systems) and Satellite Remote Sensing and incorporated slope considerations into the analysis. As a result of the study, we were able to find the areas with insufficient urban parks and provide guidelines for their selection of optimum location.

Thermal properties of PZT detectors were studied in a temperature range from 5 to 50 degrees. The sensitivity of a disk-shaped detector was flat in sensitivity, where as we found an anomalous sensitivity at 44 degree in spherical shaped one. The detectors of both disk-shaped and spherical forms were warmed up in water, into which an electron beam was irradiated. By applying corrections for the thermal properties, we have obtained experimental results consistent with previous data.

Superlattice type photodiodes of a GaAs-Al/sub x/Ga/sub 1-x/As structure were studied at room temperature. A combination of potential-well width and barrier width was sensitive to the charge multiplication factor. Using a diode with a 10 nm well and a 15 nm barrier, the detector characteristics were investigated from a point of view of achieving a high gain. This type of photodiode was confirmed to be sensitive to Cherenkov light generated in water. Effects of carrier doping up to 10/sup 18/ cm/sup -3/ at room temperature on the multiplication rate is discussed.

In order to clarify the flow dynamics of cerebrospinal fluid (CSF) in normal pressure hydrocephalus (NPH), a phase-contrast cine magnetic resonance (MR) imaging technique with retrospective cardiac gating was used to measure the quantitative flow velocity of CSF in the aqueduct in patients with NPH after subarachnoid hemorrhage (SAH-NPH group, n = 17), idiopathic NPH (1-NPH group, n = 2), asymptomatic ventricular dilatation or brain atrophy (VD group, n = 7) and healthy volunteers (control group, n = 19). Intracanial pressure (ICP) and pressure volume response (PVR) were also measured during the shunt operation in six of the SAH-NPH group. The maximum CSF flow velocity (Vmax) in the aqueduct was significantly larger in the SAH-NPH group (9.21 ± 4.12 cm/sec, mean ± SD) than in the control group (5.27 ± 1.77, p < 0.001) and the VD group (4.06 ± 1.81, p < 0.005). Vmax was not different between the control and VD groups. There was a positive correlation between the PVR and the peak CSF flow velocity in the SAH-NPH group. These findings suggest that the changes of CSF flow velocity in the SAH-NPH group might be caused by a moderate decrease of intracranial compliance. The CSF flow study using MRI is useful to differentiate NPH from brain atrophy or asymptomatic ventricular dilatation and also to estimate the intracranial compliance.

A 76-year-old woman was found to have acute aseptic meningoencephalitis with meningial irritation, disturbance of consciousness, elevation of cell counts in cerebrospinal fluid, and swelling of a right temporal-lobe lesion on a CT scan of the head. Muscle weakness in the lower extremities and urinary dysfunction developed and progressed gradually. The protein content of cerebrospinal fluid was high, and the distal latencies of F waves were prolonged, which suggested that the inflammation extended to the nerve roots. Sjögren's syndrome was diagnosed on the basis of atrophy of the labial salivary glands; invasions of lymphocytes and plasma cells to the intercellular space; and elevation of the titers of serum antinuclear antibody, anti-SS-A antibody, and anti-SS-B antibody. The patient had no xerosis. Aseptic meningoencephalitis was the first manifestation of Sjögren's syndrome. In recent years, several cases in which Sjögren's syndrome was associated with aseptic meningitis have been reported. However, we know of no previous report of such a case in a patient of this age. Aseptic meningoencephalitis can be the first manifestation of Sjögren's syndrome.

LEARNING OBJECTIVES (1)Understand images of breast specimens with microcalcifications obtained by use of micro-focus CT. (2)Learn the relationship between mammographic features, pathologic characteristics, and micro-focus CT images. (3)Learn the usefulness of three-dimensional images in understanding of detailed structures and patterns of microcalcifications without cutting the specimen. ABSTRACT Microcalcifications are one of the important sign for early detection of breast cancer by use of mammography, and has resulted in the detection of nonpalpable cancer. However, it is difficult to distinguish between benign and malignant microcalcifications, thus causing high false-positive rate. Micro-focus CT employs a x-ray tube of a focal spot size less than 10 microns, and has high spatial resolution, thus resulting in more accurate visualization of structures of microcalcifications. We investigated the relationship between micro-focus CT images of breast specimens with microcalcifications, mammographic features and pathologic characteristics. Micro-focus CT imaging was comparable to pathologic images in terms of resolution and contrast. Microcalcifications were more clearly detected in micro-focus CT imaging than specimen radiographs. Three-dimensional imaging on microcalcifications provided a tool for studying the shape and distribution of calcifications. Micro-focus CT for breast imaging was very useful for understanding of structures and patterns of microcalcifications without cutting the specimen.

This report discusses the following topics on the Soleoidal Detector Collaboration: Summary and overview of the detector; physics and detector requirements; central tracking system; superconducting magnet; calorimetry; muon system; electronics; online computing; offline computing; safety; experimental facilities; installation; test and calibration beam plan; and cost and schedule summary.

Using 1150 nm infrared light, the change in the detector sensitivity was studied. As a simple measure of the states of the detector sensitivity, the time derivative of the photocurrent is proposed. In terms of the derivative, the change is uniquely classified into two categories. Even after the detector is aged, the derivative does not remain constant with respect to time and voltage. The physical mechanisms which cause the change are discussed based on possible effects due to unstable surface states and the accumulation of an oxide layer.

Attempts have been made to improve the characteristics of glasses suitable for Cherenkov counters of the total-absorption type. Many kinds of new lead glasses were prepared and examined in the transmittance, radiation lengths, and methods of manufacturing. Several kinds of glass blocks having the dimension of 65 × 65 × 235 mm 3 were manufactured successfully. The transmittance of one of the new glasses is higher than the usual lead glass of F-2 ∗ . It was also found that the discoloration of the new glasses is smaller than the usual lead glasses upon irradiation of 60 Co γ rays of 10 4 to 10 7 Roentgens. The Cherenkov counters of the total-absorption type with the new glasses, together with the ones with usual lead glasses of F-2, SF-2, SF-5, and SF-6, were tested by using electron beams with energies from 300–1000 MeV. It was found that the energy resolution of the first ones is better by a few percents than that of the latter in the whole energy region.

Sectional surfaces of the lithium-drifted silicon detector are observed using the scanning electron microscope (SEM). Cyclic striation lines are observed in the lithium-drifted region of a detector made from a large-diameter silicon ingot. This is confirmed to be due to a cyclic fluctuation of donor impurity caused by a cyclic change of temperature during floating-zone processing. These materials are judged to be unsuitable for detector application. >

A new audio system which reproduces reflections of actual concert halls is presented. The system is based on the symmetrical six-point sound-field analysis method and a sound-field simulation method through convolution. The system reproduces realistic sound fields which cannot be reproduced by conventional stereo systems. A method for measuring hall reflections and a calculation method that displays reflections by an audio system in a listening room are described. The sound-field reproduction system based on the measurement and simulation results is described. >

A certain type of silicon rubber (KE103RTV) is found to be a useful material as an adiabatic light guide for scintillation counters because of its mechanical flexibility. The refractive index of KE103RTV is measured to be 1.410±0.006. The transmission and the resolution of scintillation light pulses through it are comarable with those through acrylic resin light guides. This RTV has the resistivity against high dose of radiation.