精巧推进村田制作所在移动设备用的多层功率电感

移动设备里供电电路的工作电压随着产品附加功能而多元化，例如移动电话同时供电给LCD驱动、功放和基带IC，但供电电路的电压是各不相同的，因此供电电路需要把电池电压转换成各个电路工作电压。同时供电电路要求的工作电压变得越来越低、越来越精确。所以极小的电压波动都会给设备带来比较高的故障率。     

State difference feedback for stabilizing uncertain steady states of non-linear systems

Supposing a non-linear system is subjected to parametric uncertainties, the present paper aims at stabilizing its unstable steady states. A distinctive feature of the problem is that exact information about the steady state is unavailable. To cope with the difficulty, we have examined the applicability of the state difference feedback which uses the difference between the present state x(t) and the past state x(t-T). A rigorous stability analysis has been executed for the case where state deviations are controllable by a single input variable. The stability analysis has led to a favourable conclusion that if the number of unstable modes is just two, and if they are not associated with the origin in the complex plane, we are always able to find a controller which stabilizes the deviations from the unknown steady state. Design process is illustrated by using two kinds of pendulum systems.     

Simplified procedure for preparation of35S-labeled brain sulfatide

A simplified procedure for the preparation of³⁵S-labeled brain cerebroside sulfates has been developed. The labeled sulfatides are synthesized in vivo after intracerebral administration of inorganic³⁵S-sulfate in developing rats. The animals are sacrificed three days later and brain homogenates extracted with chloroform-methanol. The extract is subjected to mild alkaline treatment and washed with water. The organic phase is chromatographed on triethylaminoethyl-cellulose from which sulfatides are eluted with chloroform-methanol containing potassium acetate. Radioactive fractions are pooled, concentrated, and potassium acetate removed by dialysis against water. Alternatively, salts are removed by passing radioactive fractions through Sephadex G-25. After evaporating to near dryness, the radioactive cerebroside sulfates are dissolved in a small volume of chloroform-methanol and stored at −20 C. The³⁵S-sulfatides are essentially free of lipid contaminants, and 97% of the radio-activity corresponds with sulfatides on chromatographic analysis.     

Survey of actual viewing conditions at home and appropriate luminance of LCD‐TV screens

Abstract— To understand actual viewing conditions at home is important for TV design. And the preferred luminance level of LCD TVs under actual viewing conditions is also important in order to obtain both good picture quality and low power consumption. The actual viewing conditions of households and the preferred luminance levels was investigated. In a field test of 83 households, the display luminance, screen illuminance, and viewing locations were measured on site. In laboratory experiments, young and elderly subjects adjusted the luminance of an LCD‐TV screen to their preferred levels under different screen illuminance levels, angular screen sizes, and average luminance levels (ALL) of the images. As a result, two equations, which represent the preferred luminance level of LCD‐TV screens corresponding to different viewing conditions for young and elderly subjects were obtained. When the ALL of the images was 25% and the screen illuminance and angular screen size were set at 100 lx and 20°, respectively, the preferred luminance was 1 60 cd/m² for the young subjects and 248 cd/m² for the elderly subjects. By using the setting of the preferred luminance of an LCD TV under actual viewing conditions, it is possible to conserve energy consumption.     

Synthesis and photophysical properties of structural isomers of novel 2,10-disubstituted benzofuro[2,3-e]naphthoxazole-type fluorescent dyes

Structural isomers of novel 2,10-disubstituted benzofuro[2,3-e]naphthoxazole fluorescent dyes have been synthesized. The phtophysical properties have been investigated in solution and in the solid state. The absorption and fluorescence intensities of the naphth[1,2-d]oxazoles are much stronger than those of the naphth[2,1-d]oxazoles in solution. Moreover, in the solid state, the emission intensities of the former are typically much stronger than those of latter isomers. To understand the differences in photophysical properties, semi-empirical molecular orbital calculations and the X-ray crystallographic analyses have been performed.     

Characteristics of thermally expanded core fiber

Thermally expanded core (TEC) fiber is expected to reduce fiber-to-fiber and fiber-to-laser diode connection loss. This paper describes the characteristics of TEC fiber theoretically and experimentally. We reveal theoretically that when fabricating TEC fiber the mode field diameter (MFD) is enlarged more effectively by increasing the heating temperature rather than the heating time. In the 1300-1600°C temperature range with heating times between 0 and 60 min, it is necessary to control the temperature accurately so that no deviation from the target temperature is more than ±30°C. This is in order to ensure that any connection loss caused by MFD mismatch is less than 0.1 dB. We show experimentally that the propagation loss of TEC fiber is dependent on the heating region and wavelength by using a micro burner with a propane/oxygen flame. Based on the relationship between the loss characteristics and the expanded MFD, we suggest a method for nondestructively measuring the MFD in TEC fibers     

Oxygen permeation properties and surface modification of acceptor-doped CeO2/MnFe2O4 composites

The preparation and oxygen permeation properties of the (Ce_0.8Pr_0.2)O_2−δ − x vol% MnFe₂O₄ composites, where x = 0 to 35, have been investigated. The samples were prepared by the Pechini method. In the case of Ce_0.8Pr_0.2O_2−δ, an oxygen flux density of 6 μmol⋅cm⁻²⋅s⁻¹ (L = 0.0247 cm) and the maximum methane conversion of 50% were attained at 1000^∘C. Unlike composites consisting of Gd-doped CeO₂ and MnFe₂O₄, the oxygen permeability of the (Ce_0.8Pr_0.2)O_2−δ – x vol% MnFe₂O₄ composites was almost constant regardless of the volume fraction of MnFe₂O₄; however, the optimum volume fraction of MnFe₂O₄ was determined to be 5 to 25 in the context of the chemical and mechanical stabilities under methane conversion atmosphere. In addition, the surface modification of the (Ce_0.8Gd_0.2)O_2−δ – 15 vol% MnFe₂O₄ composite was performed by using the FePt nanoparticles. The catalyst loading of 2.8 mg/cm² on the both side of the 0.3 mm-thick (Ce_0.8Gd_0.2)O_2−δ – 15vol% MnFe₂O₄ composite increased the oxygen flux density from 0.30 to 0.76 μmol⋅cm⁻²⋅s⁻¹ in the case of He/air gradients; however, the effect seems to be reduced in the case of high oxygen flux density caused by a large pO₂ gradient. Moreover, the Langmuir-Blodgett film of the FePt nanoparticles were successfully prepared on the tape-cast (Ce_0.8Gd_0.2)O_2−δ – 15vol% MnFe₂O₄ composite. Hydrophobic treatments for the surface of the composite were crucial to achieve high transfer ratio for the deposition of the LB film.     

A photocatalytic membrane reactor for gas-phase reactions using porous titanium oxide membranes

Photocatalytic membrane reactors using porous titanium oxide membranes having pore sizes of several nanometers were utilized for a gas-phase reaction of methanol. Air mixed with methanol (MeOH) vapor, the concentration of which was controlled in the range of 500–6000 ppm, was fed to the photocatalytic membrane reactor in the range of 50–500 cm³/min using several types of flow patterns. Photocatalysis with membrane permeation resulted in a large decomposition rate, compared to photocatalysis without membrane permeation. The characteristics of the reaction such as decomposition ratio of MeOH, the conversion of the decomposed MeOH to CO₂ and H₂O were found to be a function of the residence time in the reactor. The photocatalytic reaction was analyzed based on pseudo-first-order kinetics to ascertain its simplicity, and the fitted curves were found to be in a relatively good agreement with the experimental data. Apparent rate constants with and without membrane permeation were 2.5 and 1.5×10⁻⁶ m s⁻¹, respectively, indicating that the performance of the photocatalytic reaction system with membrane permeation was enhanced.     

Micro-machinability of silver–sodium ion-exchanged glass by UV nanosecond laser

Micro-machining of silver–sodium ion-exchanged lime-sodium glass was carried out using fourth harmonic generation (FHG) of Nd:YAG nanosecond laser. The laser irradiations to silver-doped glasses produced low aspect ratio and defect-free holes because of their high-optical absorptions at the vicinity of ion-exchanged surfaces. The ablation rates (i.e. removed depth per laser shot) of ion-exchanged glasses gradually decreased with the distance from glass surfaces and were saturated, corresponding to the dilution of silver ion concentration. The ablation rates and hole shapes drastically changed when the processed hole bottoms reached the ion penetration depths. Scanning electron microscope images indicated that the walls of processed holes in non-silver-containing region had irregular-shaped and porous structures. Therefore, well-designed ion distributions were necessary for the high-accuracy fabrication of micro-components. From these results, a micro-channel and a cylindrical column-shaped cantilever were fabricated on the glass substrates.