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Solar cells are the most commonly used devices in customer products to achieve power autonomy. This paper discusses a complementary approach to provide power autonomy to devices on a human body, i.e., thermoelectric conversion of human heat. In indoor applications, thermoelectric converters on the skin can provide more power per square centimeter than solar cells, particularly in adverse illumination conditions. Moreover, they work day and night. The first sensor nodes powered by human heat have been demonstrated and tested on people in 2004-2005. They used the state-of-the-art 100-muW watch-size thermoelectric wrist generators fabricated at IMEC and based on custom-design small-size BiTe thermopiles. The sensor node is completed with a power conditioning module, a microcontroller, and a wireless transceiver mounted on a watchstrap  相似文献   
3.
Characteristics of pulse signals transmitted in a multichannel information speed system widely used in physical setups of the State Research Center Institute of High-Energy Physics on a 70-GeV accelerator are studied. The simulation is carried out for various configurations of the system, taking into account special design features of the modules. The characteristics of the pulses and values of correcting (damping) components are determined, and the calculated and experimental results are compared.  相似文献   
4.
Autoantibodies-abzymes hydrolyzing DNA, myelin basic protein, and oligosaccharides have been revealed in the sera of patients with multiple sclerosis (MS). In MS, specific microRNAs are found in blood and cerebrospinal fluid, which are characterized by increased expression. Autoantibodies, specifically hydrolyzing four different miRNAs, were first detected in the blood of schizophrenia patients. Here, we present the first evidence that 23 IgG antibodies of MS patients effectively recognize and hydrolyze four neuroregulatory miRNAs (miR-137, miR-9-5p, miR-219-2-3p, and miR-219-5p) and four immunoregulatory miRNAs (miR-21-3p, miR-146a-3p, miR-155-5p, and miR-326). Several known criteria were checked to show that the recognition and hydrolysis of miRNAs is an intrinsic property of MS IgGs. The hydrolysis of all miRNAs is mostly site-specific. The major and moderate sites of the hydrolysis of each miRNA for most of the IgG preparations coincided; however, some of them showed other specific sites of splitting. Several individual IgGs hydrolyzed some miRNAs almost nonspecifically at nearly all internucleoside bonds or demonstrated a combination of site-specific and nonspecific splitting. Maximum average relative activity (RA) was observed in the hydrolysis of miR-155-5p for IgGs of patients of two types of MS—clinically isolated syndrome and relapsing-remitting MS—but was also high for patients with primary progressive and secondary progressive MS. Differences between RAs of IgGs of four groups of MS patients and healthy donors were statistically significant (p < 0.015). There was a tendency of decreasing efficiency of hydrolysis of all eight miRNAs during remission compared with the exacerbation of the disease.  相似文献   
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Yin S  Leonov O  Yu FT  Molotok VV  Kludzin VV 《Applied optics》1998,37(32):7482-7489
Acousto-optic (AO) devices are important spatial light modulators. They can be used as light-beam deflectors, rf true-time-delay lines, etc. To increase their spur-free dynamic range, we present what to our knowledge is a novel multichannel AO device structure, in which different channels have different carrier frequencies, so a wideband signal can automatically be decomposed into a set of narrow-band signals. Design, fabrication, and testing of this 24-channel, 10-mus AO spatial light modulator are addressed.  相似文献   
7.
Journal of Computer and Systems Sciences International - This review is devoted to the control problem with constraints on the magnitude and rate of change of the control action in aircraft control...  相似文献   
8.
Conclusions The proposed model of fatigue crack propagation based on the solution of the cyclic elastoplastic problem of the stress-strain state [1] makes it possible to take into account the effect of the triaxial stress state on the deformation of the material at the crack tip. The proposed algorithm of calculations of the state of damage on the basis of the principle of linear damage summation and also the agreement between the calculated and experimental data confirm the assumption on the controlling role of low-cycle damage in the mechanics of crack propagation in cyclic loading described from phenomenological positions. The main advantages of the proposed model are:The possibilities of calculating endurance in crack propagation or calculating the crack propagation rate for cases in which the variation of the range of the stress intensity factor along the crack length in structural members takes place at a variable loading asymmetry;the possibilities of describing the effect of loading asymmetry on the fatigue crack-propagation rate using only the strain criterion (Coffin's equation) since the range of the plastic strain intensity at the crack tip is, as shown in [1], a function of not only the range of the stress intensity factor K but also of its maximum value Kmax;the possibilities of describing the dependence of Kth on loading asymmetry based on the assumption on the constancy of the size of the structural element for the given material;the possibilities of describing the crack propagation rate in all the three sections of the dL/dN=f(K) diagram, starting with the values K similar to Kth and ending with the value of K at which monotonic quasistatic fracture becomes the controlling process.Translated from Problemy Prochnosti, No. 8, pp. 14–18, August, 1985.  相似文献   
9.
Ukrainian Scientific Research Institute of Special Steels (UkrNIIspetsstal') and the Krasnyi Oktyabr Plant. Translated from Metallurg, No. 2, p. 36, February, 1991.  相似文献   
10.
A model is proposed to calculate the effect of a difference in the mean velocities of particles and a gas on the turbulent structure of a jet carrying heavy impurities. The model considers the effect of all particles in a mole of the gas on the velocity of the mole at the end of its life.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 43, No. 4, pp. 541–548, October, 1982.  相似文献   
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