Annotated references on neutron and photon production from thick targets bombarded by charged particles

The literature on neutron and photon production from thick targets bombarded by charged particles has been surveyed. The survey covers fourteen journals and some internal reports and conference proceedings, mainly from 1965 up to June 1984. For each paper, applicable information is listed on type and energy of the projectile, the accelerator used, composition and thickness of the target, the experimental method, the calculation, and the quantities obtained. The references on neutron and on photon production are accessed through two indices which list the available projectile-target combinations and the projectile energy range.     

Dynamics of RC helicopter and control

It is hard to fly an RC helicopter desirably because of its dynamical instability and the fast responce of motion, so that some stabilizing control system has to be developed. The first step of design is the derivation of the mathematical model. Dynamics of a helicopter is much complicated due to the rotating blades and its validity is difficult to be evaluated. In this paper, the mathematical model of a hovering RC helicopter is derived and its validity is confirmed experimentally by designing the stabilizing control system of the gimbal equipment which has three degrees of freedom, rolling, pitching and yawing. At the same time, two kinds of small sensors are investigated and used to control the above equipment.     

Design and dynamic response characteristics of 400 MW adjustablespeed pumped storage unit for Ohkawachi Power Station

At 400 MW, the world's largest adjustable speed pumped storage unit for Ohkawachi Power Station, the Kansai Electric Power Co., Inc., Japan, was commissioned on Dec. 3, 1993. It can change power in steps of at least 32 MW in the generate mode and at least 80 MW in the pump mode, within 0.2 s. This paper describes principal design considerations for the control systems of the machine and presents actual performance of the machine with reference to some typical oscillograph charts     

Relationship between the energy distribution of electrostatic field change and lightning activity

A lightning strength parameter α (denoted as LSP or LAIDO), which is used for characterizing the phenomena of lightning activity, has been proposed, where α is defined by the characteristic energy obtained from the energy distribution of a radiated field component E in the electrostatic field changes produced by lightning discharge. Here, it is observed that the energy distribution of E_γ components is Maxwellian type. To prove more clearly the forementioned assumption from another viewpoint, changes of the amplitudes of the electrostatic field component E_S were measured and their distribution functions constructed. In the cloud-to-ground lightning discharges, the E_S components have a positive sign in the changes. However, those changes in the intercloud discharges are observed with either a negative or positive change depending on the distance between the striking point and the observation site. Therefore it is necessary to sum the numbers of occurrences of both positive and negative components for constructing an energy distribution of the E_S component. A fieldmill and a pair of doughnut-shaped electrostatic antennas are used in measuring the changes of the E_S component. As a result it is found that the changes of the amplitudes of the E_S components have a Maxwelliantype energy distribution. A characteristic energy β is defined which is obtained from the component of the electrostatic fields as a measure of LSP. Based on comparison of α and β it is clarified that β has the same characteristic nature with α. The lightning activity could be estimated from β.     

Autoantibody to DNA topoisomerase II in primary liver cancer

A patient with chronic hepatitis associated with hepatitis C virus infection was observed to convert from antinuclear antibody-negative to antinuclear antibody-positive status at the time when liver cancer was detected. The newly recognized antibodies reacted with a nuclear protein doublet of 170 and 180 kDa in immunoblotting, and in fluorescence-activated flow cytometry the antigens were shown to vary in expression level in a cell cycle-related manner: minimum in G1, increasing in S, and maximum in G2 and M. In synchronized HeLa and HEp-2 cells, immunofluorescence microscopy showed uniformly distributed staining of the nucleoplasm in S-phase, with increased intensity of nucleoplasmic staining in G2, at which time nucleolar staining was also present. In M, condensed chromosomes were uniformly stained. Using previously characterized polyclonal antibodies to DNA topoisomerase II (topo II) as reference markers, the antigens recognized by the patient's serum were shown in Western blotting to have the same mobilities as DNA topo IIalpha (170 kDa) and beta (180 kDa) isoforms. The patient's serum was also highly efficient in inhibiting DNA topo II in an in vitro functional assay. Antibody to DNA topo II appeared de novo in close association with transformation to cancer, and since dysregulation of DNA topo II is considered to be involved in some forms of tumorigenesis, the observed antibody response in this patient could conceivably be an immune reaction to the abnormally regulated protein.     

Reduced sialylation of glycoproteins in nasal glands of patients with chronic sinusitis

This study was conducted to investigate the sialylations of glycoproteins in the nasal glands of patients with chronic sinusitis. Sialic acids were detected using lectin histochemistry, and the mRNA of sialyltransferase was evaluated by in situ hybridization histochemistry. Sambucus nigra agglutinin (SNA), which recognizes terminal sialic acids, strongly stained the glandular mucous cells of normal subjects, but not those of patients with chronic sinusitis. In situ hybridization histochemistry showed that the expression of alpha2,6 sialyltransferase mRNA was decreased in the secretory cells of patients with chronic sinusitis. Our present results suggest that a reduction in sialyltransferase activity at the mRNA level in the nasal glands may lead to the persistence of chronic sinusitis.     

A 0.25-μm CMOS 0.9-V 100-MHz DSP core

This paper describes a 0.25-μm CMOS 0.9-V 100-MHz DSP core which is composed of a 2-mW 16-b multiplier-accumulator and a 1.5-mW 8-kb SRAM. High-speed operation with a supply of less than 1 V has been achieved by developing 0.25-μm CMOS technology, reducing threshold voltage to 0.3 V, developing tristate inverter 3-2/4-2 adders for the multiplier, realizing small bit-line swing operation for the SRAM, and so on. The adder circuits operate faster than conventional adders at low supply voltages. In addition, short-circuit current and area for diffusion contact are reduced. Small bit-line swing operation has been realized by using a device-deviation immune sense amplifier. Leakage current during sleep mode was reduced by the use of high threshold voltage MOSFETs     

System reliability analysis of existing structures

In this paper a system reliability analysis of existing structures is presented which can account for the structural deterioration and damage resulting from impact, corrosion and crack.     

Evolutionary learning of fuzzy logic controllers and theiradaptation through perpetual evolution

This paper presents an adaptive control architecture, where evolutionary learning is applied for initial learning and real-time tuning of a fuzzy logic controller. The initial learning phase involves identification of an artificial neural network model of the process and subsequent development of a fuzzy controller with parameters obtained via a genetic search. The neural network model is utilized for evaluating trial fuzzy controllers during the genetic search. The proposed adaptive mechanism is based on the concept of perpetual evolution, where parameters of the fuzzy controller are updated at each time step with solutions extracted from a continuously evolving population of trials. There are two mechanisms that accommodate the real-time changes in the control task and/or the process into the continuous genetic search: a scheme that dynamically modifies the fitness evaluation criteria of the genetic algorithm, and an online learning of the neural network model used for evaluating the trial controllers. The potential of using evolutionary learning for real-time adaptive control is illustrated through computer simulations, where the proposed technique is applied to a chemical process control problem     

Porous mullite honeycomb by hydrothermal treatment of fired kaolin bodies in NaOH

A conventional hydrothermal treatment with various concentrations of NaOH was used at 150° and 190°C to dissolve excess silica glass and thus make porous mullite ceramics from a fired New Zealand kaolin body. The effect of hydrothermal treatment time on the dissolution of the glass was examined. At 150°C, the dissolution of glass was almost complete after treatment for 8 hrs in 5N-NaOH solution and about 40–43 wt% of the glass was removed from the fired kaolin body leading to porous mullite. However, when the fired kaolin body was treated for more than 5 hrs in 5N-NaOH at 190°C, a composite of mullite and a nonporous crystalline phase of unknown symmetry resulted. These crystals formed from the dissolution and recrystallization of the glass. After the dissolution of glass in 2N-NaOH solution at 190°C for 5 hrs, a porous mullite body of 52.8% porosity with an average pore diameter of 0.57 m could be obtained, and this was only composed of mullite whiskers. Growth of unidentified nonporous crystals in the body which was treated in 5N-NaOH solution at 190°C led to a decrease in specific surface area and therefore, these crystals should be avoided.