Disaster-readiness of medical facilities in Aichi Prefecture

One month following the Great Hanshin Earthquake of January 17, 1995, we conducted a survey of 173 hospitals in Aichi Prefecture to pinpoint problems related to their actual disaster-readiness and the medical backup systems in place to deal with such disasters. This study revealed that staff at 50% of the surveyed hospitals could reach the hospital within an hour, but that communication is almost entirely dependent on phone lines, suggesting that cordless/portable/mobile phones, radio systems, Internet, communications satellites and the like should be studied in the days to come for possible use as effective communication alternatives in times of disaster. Whereas 92% of the surveyed hospitals had manuals dealing with fire outbreaks, other areas were less well represented. For example, only 36.9% of surveyed hospitals had manuals for earthquakes, 31.7% had manuals for power outages and 14.2% had manuals to deal with flooding and water disasters. New manuals must be developed incorporating the key points garnered from experience (especially Hanshin) and be ready for use immediately. It is the time for each hospital to seriously rethink the measures it should take to deal with disasters.     

Extremely low-loss 1.5%-/spl Delta/ 32-channel athermal arrayed-waveguide grating multi/demultiplexer

A silica-based 1.5%-/spl Delta/ 100 GHz-spacing 32-channel athermal arrayed-waveguide grating (AWG) with compact size and extremely low insertion loss is described. By reducing the fibre coupling loss and the excess loss in a silicone-filled groove, an insertion loss of 1.3 dB was achieved with this athermal AWG.     

Design of Polarization-independent Wavelength-interleave Coupler in Fluorinated Polyimide Waveguide

Based on the measurement of dispersion characteristic and birefractive index of the fluorinated polyimide film,a statistical optimum design method is proposed and used to realize the design of 32-and 36-wavelengths optical waveguide wavelength-interleave coupler (i,e.,interleaver) with the optimization of polarization fluctuation and wavelength interval of 0.8nm at 1550nm. The largest cross coupling ratios of the two interleavers are respectively less than 1.8% and 3.5%, while the least through coupling ratios are respectively greater than 98. 2% and 96. 5%. The output differences due to polarization fluctuation are less than 1.7% and 3.2%     

[110]-surface strained-SOI CMOS devices

We have newly developed [110]-surface strained-silicon-on-insulator (SOI) n- and p-MOSFETs on [110]-surface relaxed-SiGe-on-insulator substrates with the Ge content of 25%, fabricated by applying the Ge condensation technique to SiGe layers grown on [110]-surface SOI wafers. We have demonstrated that the electron and the hole mobility enhancement of [110]-surface strained-SOI devices amounts to 23% and 50%, respectively, against the mobilities of [110]-surface unstrained MOSFETs. As a result, the electron and the hole mobility ratios of [110]-surface strained-SOI MOSFETs to the universal mobility of (100)-surface bulk-MOSFETs increase up to 81% and 203%, respectively. Therefore, the current drive imbalance between n- and p-MOS can be reduced. Moreover, both the electron and the hole mobilities of the [110]-surface strained-SOIs strongly depend on the drain current flow direction, which is qualitatively explained by the anisotropic effective mass characteristics of the carriers on a [110]-surface Si. As a result, the [110]-surface strained-SOI technology with optimization of the current flow directions of n- and p-MOS is promising for realizing higher speed scaled CMOS.     

Insights into multistep phosphorelay from the crystal structure of the C-terminal HPt domain of ArcB

The histidine-containing phosphotransfer (HPt) domain is a novel protein module with an active histidine residue that mediates phosphotransfer reactions in the two-component signaling systems. A multistep phosphorelay involving the HPt domain has been suggested for these signaling pathways. The crystal structure of the HPt domain of the anaerobic sensor kinase ArcB has been determined at 2.06 A resolution. The domain consists of six alpha helices containing a four-helix bundle-folding. The pattern of sequence similarity of the HPt domains of ArcB and components in other signaling systems can be interpreted in light of the three-dimensional structure and supports the conclusion that the HPt domains have a common structural motif both in prokaryotes and eukaryotes.     

Time-dependent deformation in an enhanced SiC/SiC composite

Time-dependent deformation in an enhanced SiC/SiC composite has been studied under constant load at high temperatures of 1200 °C, 1300 °C, and 1400 °C. Creep damage evolution was evaluated by a Young’s-modulus change of partial unloading and microscopic observation. The addition of the glassy phase in the matrix is very effective for protecting the composite from oxidation. The transient creep is dominant in creep life at all the temperatures. An empirical equation is proposed to describe creep behavior of the composite. It is found that creep activation energy increases with creep time at stresses lower than matrix cracking stress, but the activation energy remains constant at stresses higher than the matrix cracking stress. The creep strain rate of the composite is considered to be controlled by creep of fibers based on examining the time, strain, stress, and temperature dependencies of creep strain rates.     

An all-digital analog-to-digital converter with 12-/spl mu/V/LSB using moving-average filtering

A compact, high-resolution analog-to-digital converter (ADC) especially for sensors is presented. The basic structure is a completely digital circuit including a ring-delay-line with delay units (DUs), along with a frequency counter, latch, and encoder. The operating principles are: (1) the delay time of the DU is modulated by the analog-to-digital (A/D) conversion voltage and (2) the delay pulse passes through a number of DUs within a sampling (= integration) time and the number of DUs through which the delay pulse passes is output as conversion data. Compact size and high resolution were realized with an ADC having a circuit area of 0.45 mm/sup 2/ (0.8-/spl mu/m CMOS) and a resolution of 12 /spl mu/V (10 kS/s). Its nonlinearity is /spl plusmn/0.1% FS per 200-mV span (1.8-2.0 V), for 14-b resolution. Sample holds are unnecessary and a low-pass filter function removes high-frequency noise simultaneously with A/D conversion. Thus, the combination of this ADC and a digital filter that follows can eliminate an analog prefilter to prevent the aliasing before A/D conversion. Also, both this ADC can be shrunk and operated at low voltages, so it is an ideal means to lower the cost and power consumption. Drift errors can be easily compensated for by digital processing.