Studies on local structure in hydrogenated amorphous LaNi5.0 films using extended X-ray absorption fine structure

The local structure in hydrogenated amorphous LaNi_5.0 film was analysed by means of extended X-ray absorption fine structure. The short-range order in the amorphous LaNi_5.0 film was found to be little affected by the absorption of hydrogen. The lengthening of the interatomic distance with an increase in hydrogen concentration was much smaller for an amorphous film than for a crystalline bulk, so that the amorphous film appears to have excellent durability with regard to the hydrogen absorption-desorption process.     

Determination of urinary and serum pentosidine and its application to elder patients

Pentosidine, a fluorescent cross-linking compound, accumulates in extracellular matrix, especially in the collagen, and is formed by the nonenzymatic process of advanced Maillard reaction. We developed a method of determination of pentosidine and tried to examine its level in urine and serum of elder patients. The method, which involves the hydrolysis of samples, pretreatment using a CF-11 cellulose column and HPLC quantification, resulted in a high recovery (94.3%) of pentosidine with low coefficient of variation (8-10%) of total analysis. Serum and urinary levels of pentosidine in control subjects gradually increased with age. Elder patients with cerebral infarction showed higher levels of serum and urinary pentosidine as compared with those with senile dementia and other geriatric disorders. These results suggest that serious damage to systemic vascular tissues has already occurred in these patients due to glycation.     

Application of improved PSO to power flow control by TCSC for maximum acceptance of requested wheeled power

Open access to electric power transmission networks has been carried out in order to foster generation competition and customer choice worldwide. When several PPSs request to simultaneously supply power to customers based on bilateral contracts, it is expected that the transmission network accepts amounts of wheeled power requested by the PPSs as much as possible. It is possible to maximize total requested wheeled power by controlling power flow through transmission lines. It is well known that FACTS device is available to control line flow flexibly. In this paper, in order to maximize total wheeled power simultaneously requested by several PPSs, the authors propose an algorithm to determine the optimal reactance of TCSC (a type of FACTS device). The proposed algorithm is based on Particle Swarm Optimization (PSO), which is an optimization method based on swarm intelligence. In the proposed algorithm, PSO is improved to enhance ability of searching global minimum by giving different characteristic to behavior of each agent. In order to check the validity of the proposed method, numerical results are shown for 6 and IEEE 30 bus system models. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 155(2): 17–26, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20085     

Nanoscale solid-state quantum computing

Most experts agree that it is too early to say how quantum computers will eventually be built, and several nanoscale solid-state schemes are being implemented in a range of materials. Nanofabricated quantum dots can be made in designer configurations, with established technology for controlling interactions and for reading out results. Epitaxial quantum dots can be grown in vertical arrays in semiconductors, and ultrafast optical techniques are available for controlling and measuring their excitations. Single-walled carbon nanotubes can be used for molecular self-assembly of endohedral fullerenes, which can embody quantum information in the electron spin. The challenges of individual addressing in such tiny structures could rapidly become intractable with increasing numbers of qubits, but these schemes are amenable to global addressing methods for computation.     

Relationship between thermal degradation behavior and flame retardancy on polycarbonate–polydimethylsiloxane block copolymer

This article describes the thermal degradation behavior of polycarbonate–polydimethylsiloxane (PC–PDMS) block copolymer with dimethylsiloxane (DMS) block size 15 to 350 units, and the effects of the PDMS block size and the PDMS content on thermal degradation were studied. PC–PDMS block copolymer with DMS unit of 100 had the lowest value of maximum weight loss rate and the most residue containing silica in the other PC–PDMS block copolymers. The PDMS block size influenced PDMS dispersibility in PC and the moderate PDMS dispersion (? 50 nm) caused high flame retardancy for PC. The control of nanodispersion of PDMS caused the change of thermal degradation behavior and high flame retardancy in PC. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 1697–1705, 2006     

Noncontact AE measurement system using acoustic microscope

The surface of a slide glass (a specimen) with a notch was set in water at the focal region of a point-focus-beam lens to detect the AE (acoustic emission) signals radiating from cracks around the notch during a three point bending test. Output signals received by a transducer with a centre frequency around 50 MHz were amplified and A/D converted at a sampling rate of 200 MHz by a digital oscilloscope. The power spectra of the output signals were compared for the two cases with and without the weight used for the application of fracturing stress on the glass specimen. AE signals with a frequency range from a few megahertz to 100 MHz were successfully detected with this system for the glass specimen mounted on a small three point bending test bench.<>     

Stability analysis and design for aircraft gust alleviation control

This paper is concerned with the stability analysis and the development of an on-line two-level gust alleviation control system for a high-speed aircraft operating in an unknown environment. As is well known, such an aircraft experiences dynamic instability in its lateral motion when subjected to the longitudinal and lateral gusts. This is due to the phenomenon of lateral-longitudinal aerodynamic cross-coupling.In the first part of this paper the instability behaviour, in the presence of a longitudinal gust, of two typical high-speed aircraft is analyzed. From theoretical and simulation studies it is shown that for a sinusoidal gust, and for a given configuration, the instability region is a function of both the amplitude and frequency of the gust disturbance.In the second part of the paper, an on-line gust alleviation control system is synthesized for such an aircraft operating over a wide range of unknown environmental conditions. This control system employs a two-level control structure. The controller, however, does not require an explicit knowledge of the aircraft parameters or the environment. Typical simulation results are presented which verify the theoretical predictions.