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51.
A novel, unobtrusive and wearable, multiparameter ambulatory physiologic monitoring system for space and terrestrial applications, termed LifeGuard, is presented. The core element is a wearable monitor, the crew physiologic observation device (CPOD), that provides the capability to continuously record two standard electrocardiogram leads, respiration rate via impedance plethysmography, heart rate, hemoglobin oxygen saturation, ambient or body temperature, three axes of acceleration, and blood pressure. These parameters can be digitally recorded with high fidelity over a 9-h period with precise time stamps and user-defined event markers. Data can be continuously streamed to a base station using a built-in Bluetooth RF link or stored in 32 MB of on-board flash memory and downloaded to a personal computer using a serial port. The device is powered by two AAA batteries. The design, laboratory, and field testing of the wearable monitors are described.  相似文献   
52.
The article presents results of theoretical and experimental investigation of quasioptical multiplexer based on reflecting diffraction grating. Diffraction losses caused by reflection into mirror harmonic, and by angle divergence of wave beams are calculated. In an experimental multiplexer, wave beams with the frequencies 70 GHz and 79 GHz were mixed with power losses less than 1%.  相似文献   
53.
A mathematical model has been developed to predict So2 absorption and removal during the constant rate drying period of a spray dryer. The model, based on film theory, treats the atomized slurry droplets as spheres containing discrete sorbent particles of slaked lime with the fluid uniformly distributed around the individual particles. The model includes gas and liquid phase mass transfer coefficients as well as resistance to Ca(OH)2 dissolution. A sensitivity analysis has been conducted and a comparison was made between pilot-scale experimental data and model-predicted values of S02 removal efficiency.  相似文献   
54.
The dissolution rate of sapphire into CaO-MgO-Al2O3-SiO2 (CMAS) melts was investigated at 1450° and 1550°C. The effects of immersion time, specimen rotation rate, and magnesia concentration in the bulk melt on the sapphire dissolution rate and on the growth rate of magnesium aluminate spinel at the sapphire/melt interface were determined. The processes of direct and indirect sapphire dissolution into CMAS melts are discussed, with the support of kinetic and microprobe data.1 A model of indirect sapphire dissolution1,2 is used along with the equations of Tedmon3 to describe the kinetics of indirect dissolution and spinel layer growth during forced-convective and static sapphire dissolution.  相似文献   
55.
Improvement of the interface contact between biological objects and electronic devices can significantly enhance the quality of electronic signal transfer. The surface of biosensor can be artificially modified in order to strengthen the adhesion of biological cells. We report on results of fabrication of micron and submicron golden spines by means of e-beam lithography and electroplating. The fabrication technique allows easy modification of the size and shape of golden spines by variation of processing parameters. The structures with different spine profiles and spacing have been fabricated for optimization of cell growth conditions. We present the results of growth of rat cortical neurons on the surface of spine modified samples. Well-defined cell guidance was established at the spine arrays. Furthermore, the results of transmission electron microscope and focused ion beam technique confirm the good adhesion between the spines and cell structures.  相似文献   
56.
Treatment with low-energy ions and measurements of electrical parameters of samples have been used to study the defect structure of Cd x Hg1 − x Te films grown by liquid-phase epitaxy. The films contain neutral defects supposedly associated with tellurium nanoinclusions. Ion treatment electrically activates these defects, with a high concentration of donor centers (∼1017 cm−3) created in the films. These defects decompose in ∼103 min of aging at room temperature. Then the properties of the material are determined by the concentration of residual donors, which is found to be very low (down to ∼1014 cm−3) for the films under study.  相似文献   
57.
The fabrication technology and properties of light-emitting Si structures codoped with erbium and oxygen are reported. The layers are deposited onto (100) Si by molecular beam epitaxy (MBE) using an Er-doped silicon sublimation source. The partial pressure of the oxygen-containing gases in the growth chamber of the MBE facility before layer growth is lower than 5 × 10?10 Torr. The oxygen and erbium concentrations in the Si layers grown at 450°C is ~1 × 1019 and 1018 cm?3, respectively. The silicon epitaxial layers codoped with erbium and oxygen have high crystal quality and yield effective photoluminescence and electroluminescence signals with the dominant optically active Er-1 center forming upon postgrowth annealing at a temperature of 800°C.  相似文献   
58.
The equivalent series resistance (ESR) of today's components continues to improve which makes the measurement of low ESR values a significant challenge. ESR measurement errors include the choice of measurement equipment/technique, traceability from national laboratories, and the interfacing and contacting to the device.  相似文献   
59.

AktuellKelag und Rwe

Kompetenzzentrum Wasserkraft  相似文献   
60.
We report the use of a terahertz (THz) receiver fabricated using a photoconductive antenna mounted upon a distributed Bragg reflector (DBR). It is shown that the relative performance of the device is in accordance with the reflectivity curves of the DBR. At maximum reflectivity the device improved upon the reference THz signal by up to 30%. In addition, we characterize the saturation of the device with laser pump power and it is shown that the device exhibits an improved optical efficiency when compared to the reference receiver.  相似文献   
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