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41.
Most of the previous studies on inverse systems have treated only the case where all components of the input of the original system are recoverable. However, even when not all components are recoverable, there is still a possibility of reproducing part of the input. As a generalization of the inverse of a linear time-invariant dynamical system to include such cases, ‘α-integral F-inverse’ is proposed in this paper which reproduces the αth integral of a linear function Fu of the input vector u. A necessary and sufficient condition for the existence of an α-integral F-inverse is derived. A construction procedure of such an inverse is also given along with a numerical example.  相似文献   
42.
The synthesis of the enantiomeric 14-methyl-1-octadecenes in >99% EE is described. Enantiomeric 2-methyl-1-hexanols were intermediates in the synthesis. The 1-alkene had been previously identified as the sex pheromone of the peach leafminer moth. Several closely related structures that have 12 unsaturation are also described.Reference to brand or firm name does not constitute endorsement by the U.S. Department of Agriculture over others of a similar nature not mentioned.  相似文献   
43.
We propose a method for extracting the left ventricular (LV) contours from left ventriculograms by means of a neural edge detector (NED) in order to extract the contours which accord with those traced by a cardiologist. The NED is a supervised edge detector based on a modified multilayer neural network, and is trained by use of a modified back-propagation algorithm. The NED can acquire the function of a desired edge detector through training with a set of input images and the desired edges obtained from the contours traced by a cardiologist. The proposed contour-extraction method consists of 1) detection of "subjective edges" by use of the NED; 2) extraction of rough contours by use of low-pass filtering and edge enhancement; and 3) a contour-tracing method based on the contour candidates synthesized from the edges detected by the NED and the rough contours. Through experiments, it was shown that the proposed method was able to extract the contours in agreement with those traced by an experienced cardiologist, i.e., we achieved an average contour error of 6.2% for left ventriculograms at end-diastole and an average difference between the ejection fractions obtained from the manually traced contours and those obtained from the computer-extracted contours of 4.1%.  相似文献   
44.
This paper discusses closed-loop identification of unstable systems. In particular, we first apply the joint input–output identification method and then convert the identification problem of unstable systems into that of stable systems, which can be tackled by using kernel-based regularization methods.We propose to identify two transfer functions by kernel regularization, the one from the reference signal to the input, and the one from the reference signal to the output. Since these transfer functions are stable, kernel regularization methods can construct their accurate models. Then the model of unstable system is constructed by ratio of these functions. The effectiveness of the proposed method is demonstrated by a numerical example and a practical experiment with a DC motor.  相似文献   
45.
The dynamic properties of a 1.3 μm light-emission-and-detection (LEAD)-diode module that has a high mesa semi-insulating buried heterostructure (SI-BH) to reduce the capacitance of the chip (0.6-0.8 pF) are described. A modulation bandwidth of 12 GHz in laser diode (LD) operation, and detection bandwidth of ~1.9 GHz in photodetector (PD) operation are achieved using a chip and a module, respectively. In bit error rate (BER) performance at 30 Mbit/s, a receiver sensitivity (BER=10-8) of -37.4 dBm is confirmed, and a switching time of under 1 μs from LD to PD operation is estimated using a circuit simulator  相似文献   
46.
This paper presents a novel approach to reconstruct the output of linear systems in the case where the measured output is uniformly quantized. By fitting the quantized measurements with polynomials in a moving horizon manner, a smooth signal is reconstructed by solving a convex optimization problem with ?1‐norm regularization. The quantization feature and the system models are taken into account in the optimization. A numerical example is given to show the excellent reconstruction performance of the proposed method. In addition, the proposed method is implemented in a high‐precision linear stage through DSP, and its effectiveness is verified through experiments using a real positioning system.  相似文献   
47.
While ultraviolet radiation alters various cutaneous cell functions, little is known about the photobiological effects of infrared radiation (IR) on the skin except its local thermal effect. This study demonstrated that single exposure of mouse skin to near IR (0.7-1.3 microns) reversibly suppressed the proliferating activity of the epidermis, the density of Langerhans cells, and the ability of skin to induce contact hypersensitivity reaction. During the exposure, the ear surface temperature was elevated from a mean of 27 to 31.2 degrees C. The results suggest that near IR can modulate the epidermal proliferation and part of the skin immune system, with a mild thermal effect.  相似文献   
48.
A nonrepeated fibre transmission experiment over 308 km of conventional optical fibre is reported at 2.5 Gbit/s in a CPFSK heterodyne detection system. The system has a sensitivity of -46.7 dBm or 67 photons/bit at 10/sup -9/ BER and has the maximum allowable attenuation of 55.1 dB without an optical amplifier.<>  相似文献   
49.
An equation for determining the difference between the compressibility factors of saturated vapor and liquid (ZV - ZL) through cubic equations of state has been developed as a function of reduced vapor pressure Pr, reduced temperature Tr and the critical cohesion parameter Ωac of the chosen equation. The regressed equation has been presented in a polynomial expression of (Pr/Tr) and Ωac for simple non-iterative calculations.  相似文献   
50.
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