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71.
In obstruction of both lacrimal ducts at present the most frequently used method is conjunctivo(dacryo)cystorhinostomy using a Jones bypass cannula. The effectiveness of the procedure is 85-90%. The drainage cannulas can be straight or bent and are as a rule made from pyrex glass. The patients should be highly motivated and made familiar with possible complications, i.e. most frequently escape of the cannula. With regard to the necessary postoperative cooperation the operation is not recommended in young children. The authors performed in 1996-1997 a total of 8 conjunctivo(dacryo)cystorhinotomies. The lacrimal sac is opened into the nose under general anaesthesia by the endonasal route using endoscopes. In one instance the authors used a straight silicone cannula which fell out after three weeks. In the remaining patients they used a bent silicone cannula. Seven patients evaluate their condition after surgery as markedly improved and would be willing to have the operation again. One female patient (after escape of a straight cannula and later reinsertion of a bent cannula) would hesitate to have another operation. The authors evaluate their experience with this type of bypass operation as very satisfactory. 相似文献
72.
Evaluation tests are carried out on the direction finder, which has an aperture comprising four monopoles on the circumference of 0.4 /spl lambda/. Radial bias function (RBF) neural network and a new post-processing procedure are used in the algorithm of DOA estimation. The estimation error was reduced to one-tenth that of MUSIC. 相似文献
73.
74.
Miyamoto Y. Kataoka T. Yonenaga K. Tomizawa M. Hirano A. Kuwahara S. Tada Y. 《Lightwave Technology, Journal of》2002,20(12):2115-2128
This paper describes recent technical challenges and the progress toward the realization of the optical transport network (OTN) based on 43 Gb/s channel. We describe the new digital frame format "OTU3: Optical Channel Transport Unit 3," which is standardized in ITU-T for OTN, for the enhancement of the network management capability in the OTN based on 43-Gb/s channels. We first proposed 43-Gb/s/ch dense wavelength-division multiplexing (DWDM) dispersion-managed transmission system using carrier-suppressed return-to-zero (CS-RZ) format that has several attractive features; it advances the evolution of OTN into 100 GHz-spaced long-haul DWDM transport networks. The first wavelength-division multiplexing (WDM) field trials confirmed the superiority of CS-RZ format in the DWDM transmission performance for the first time. The first 1 Tb/s (25 /spl times/ 43 Gb/s) WDM field trial confirmed the excellent network management capability of OTU3 in future data-centric OTN using the newly developed 43-Gb/s OTN line-terminal prototype. 相似文献
75.
ITA Working Group on Catalogue of Tunnels S. Kuwahara Animateur 《Tunnelling and Underground Space Technology incorporating Trenchless Technology Research》1990,5(3)
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
76.
77.
Naoya Kikuchi Shinsuke Mori Hideyuki Asai 《Journal of the Society for Information Display》2005,13(11):955-960
Abstract— We have proposed a counterelectrode PDP structure in which the sustain and scan electrodes are embedded face to face in the ribs by applying Thick‐Film Ceramic Sheet technology. An advantage of the counterelectrode PDP is low discharge voltage, which does not depend on the dielectric thickness. A positive column is observed at a longer gap, and the luminous efficacy reaches 3.7 lm/W at Ne‐30%Xe at a 450‐μm discharge gap. 相似文献
78.
Solar Cells: High Efficiency Cu2ZnSn(S,Se)4 Solar Cells by Applying a Double In2S3/CdS Emitter (Adv. Mater. 44/2014)
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79.
Samia Tabassum Eiji Yamasue Hideyuki Okumura Keiichi N. Ishihara 《Journal of Materials Science: Materials in Electronics》2014,25(11):4883-4888
Al-doped ZnO (AZO) thin film, which possess the advantages of low cost, low sheet resistance and high transmittance, are one of the most promising candidates to replace indium tin oxide films as the transparent electrode. However, oxidation causes a substantial increase in the sheet resistance of AZO film after exposing in ambient and especially, damp heat environment. In this work, we compare structural, optical, electrical properties and environmental stability between films prepared by two different methods: sol–gel and rf sputtering. Experimental results indicate that the properties of film can be affected by different deposition method. From the X-ray diffraction analysis, all films have hexagonal wurtzite crystal structure with different preferable orientation in two different methods. Optical transmittance spectra of the AZO films exhibited transparency higher than about 80 % within the visible wavelength region and the optical band gap (Eg) of these films was increased in sputtered film, probably due to the increase of carrier concentration. The better environmental stability was found in AZO film prepared by sputtering method. Improved surface morphology and enhancement of crystal orientation (110) was considered for this improvement. 相似文献
80.
Satoshi Hiraoka Takeshi Fujii Hideyuki Takakura Yoshihiro Hamakawa 《Solar Energy Materials & Solar Cells》2003,75(3-4):781-786
One-year field experience of an 80 kW PV system on a rooftop of the ROHM Memorial VLSI Research Center at the Ritsumeikan University is reported. All kinds of live technology available materials, c-Si, poly Si and a-Si solar cells are installed on the three tilt angles of 26.5° south, horizontal and north 26.5°. Systematic PV performances have been measured from the beginning of June 2000 to the end of May 2001. Measurements were made mainly on DC output power from four kinds of PV arrays; c-Si south side, a-Si of horizontal and poly Si, a-Si north side. It has been shown from analyses of monthly data on each material that almost 70% of with that in the south side in the annual average. In summer a-Si module yields the maximum output power normalized to 1 kWp. On the contrary c-Si module shows larger output in winter. Some other unique results are demonstrated and discussed. 相似文献