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31.
Beginning in 1986, the International Tunnelling Association's Working Group on the Catalogue of Tunnels has produced three volumes summarizing data on tunnel projects throughout the world. The animateur (chairman) of the Working Group describes the tunnel project summaries, their uses to date, and future plans.  相似文献   
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Electrically conducting adhesive films containing silver nanosized particles (AgNPs) were prepared using siloxane polyimide resin (SPI), and their physical properties were investigated. AgNPs with diameters of ca. 6 nm were prepared using oleylamine as a stabilizer. A mixture of the AgNPs and SPI was vigorously stirred, and cast on a polyethylene terephthalate support. Films were then fabricated using a doctor blade method. The heat resistance of the SPI film containing 60 wt% AgNPs was 35 °C higher than that of the SPI film without AgNPs. In addition, epoxy composite SPIAg (Epo-SPIAg) films containing a mixture of AgNPs and micro-sized silver flakes were prepared. Inclusion of AgNPs in these films strengthened their adhesion to silicon or bismaleimide triazine resin substrates. The glass transition temperature of the Epo-SPIAg films containing AgNPs was slightly higher than that of the film containing only micro-sized silver flakes.  相似文献   
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Signal multiplexing techniques for coherent optical transmission are compared, and appropriate application for a coherent subcarrier multiplexing (SCM) system is discussed. Optical frequency modulation (FM) using direct modulation of a distributed-feedback laser diode (DFB-LD) and a heterodyne detection is shown to be feasible. A transmission system using a local laser in the transmitter is unaffected by polarization and is cost effective. Phase noise can be suppressed by a phase-noise-canceling circuit (PNC) in a heterodyne receiver. This circuit can also effectively compensate for the frequency of instability of light sources. A theoretical simulation of a coherent SCM system showed that 100 channels of 30-MHz FM signal or 15 channels of 155-Mb/s signal can be distributed to 10000 subscribers using single-stage or double-stage optical amplifiers  相似文献   
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We have cloned a cDNA for a novel human homolog of the Drosophila discs large (dig) tumor suppressor protein, termed NE-dlg (neuronal and endocrine dig). Northern blot analysis revealed that the gene is highly expressed in neuronal and endocrine tissues. Fluorescence in situ hybridization (FISH) and radiation hybrid mapping studies localized the NE-dlg gene to chromosome Xq13. We also found that the NE-dlg gene encoded a 100 kDa protein. Immunolocalization studies using an NE-dlg antibody showed that the protein tended to be expressed in non-proliferating cells, such as neurons, cells in Langerhans islets of the pancreas, myocytes of the heart muscles, and the prickle and functional layer cells of the esophageal epithelium. Proliferative cells, including various cultured cancer cell lines and basal cells in the esophageal epithelium, showed little expression of the NE-dlg protein. In addition, yeast two-hybrid screening and in vitro binding assays revealed that the NE-dlg interacted with the carboxyl-terminal region of the APC tumor suppressor protein. These data suggest that NE-dlg negatively regulates cell proliferation through its interaction with the APC protein.  相似文献   
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Proposes a simple automatic chromatic dispersion compensation system that can detect the zero-dispersion point of an installed fiber span. This technique realizes high sensitivity without requiring the system to be extensively modified. The alternating chirp signal, which is used as the zero-dispersion-detection signal, has alternating optical frequency shift. It can be generated simply by changing the input signals of multiplexer circuits and shifting the bias voltage of the LiNbO/sub 3/ modulator. This technique is shown to detect the zero-dispersion point in the range of -600 to +600 ps/nm by using the signal modulated at 10 GHz; automatic dispersion compensation is successfully demonstrated in a 20-Gb/s, 400-km transmission experiment in our laboratory. Compensation is also demonstrated in 281-km-installed dispersion-shifted fiber using a 20-GHz alternating chirp signal.  相似文献   
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Radiocardiography has been widely used as a method for the quantification of cardiac output by applying the principle of the dye dilution method. This paper deals with an automatic analyzing system of radiocardiograms and a parameter estimation procedure using a linear system made up of four compartments with two time delays as a model of transport process in the blood circulatory system. The parameter estimation procedure named the window method in frequency domain is very effective for shortening the computing time and can be easily performed using a minicomputer. Parameter sensitivity analysis is also applied to study behavior of parameters on the model. Some analyzed results of radiocardiograms are shown and it is verified that the procedure is sufficiently useful and efficient for routine clinical use.  相似文献   
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In this paper an overview is presented on R&D of medical imaging and image processing techniques in Japan during the last decade, focusing on case studies in the diagnosis of cardiac diseases.Various problems of image processing of left ventricular images obtained from x-ray, ultrasound and radionuclides are discussed. Also reviewed are boundary detection methods of left ventricular inner cavity and myocardium, analysis of left ventricular wall motion and various kinds of cardiac functions using conventional and newly developed methods, and display methods of these cardiac functions.Microcomputerized on-line image processing systems and a compound sector scan echocardiography using two probes developed for echocardiographic examinations are shown with some results in clinical applications.3-dimensional reconstruction methods of the left ventricle and other organs from multiple 2-dimensional images are shown with 3-dimensional shapes reconstructed from images by x-ray, ultrasound and radionuclides. Moreover, 3-dimensional functional images of the left ventricle are shown as well. Transferring the 3-dimensional consecutive left ventricular images during a cardiac cycle onto a CRT display under the control of a microprocessor, we can observe the pulsating 3-dimensional left ventricle on the CRT.  相似文献   
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