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151.
Onodera R. Ishii Y. Ohde N. Takahashi Y. Yoshino T. 《Lightwave Technology, Journal of》1995,13(4):675-681
A dynamic interferometer with a frequency-ramped laser diode (LD) has been constructed that is based on an optical heterodyne technique. Effect of LD power change on the optical heterodyne interferometry has been investigated theoretically and experimentally. A general formulation of the interferometry has been presented in which the demodulation scheme is analyzed in the frequency domain by Fourier-transforming a beat signal. Phase errors caused by the LD-power variation alter sinusoidally with the same period as the interference beat signal. The error can be eliminated by using an amplitude-stabilized, frequency-modulated laser diode source in the interferometer. The stabilization of the LD amplitude can be achieved by a feedback system with a superluminescent diode as an external light-power controller 相似文献
152.
This paper proposes a scheme for fast and reliable handover that uses dynamic rerouting controlled by a call setup control
station (CCS) operating in mobile asynchronous transfer mode (ATM) networks. The CCS selects appropriate rerouted path and
crossover switch (COS), and remotely controls the new path's setup. This omits crossover switch discovery process, and makes
fast handover possible. The CCS can select the appropriate rerouted path because it directly and with little delay collects
information about the state of links such as traffic loads, quality-of-service (QoS) parameters, and disconnection or restoration
of links advertised from every ATM switch in its domain. This reduces blocking and congestion, and makes reliable handover
possible. The CCS accepts a handover request message for either backward or forward handover, and can remotely control the
new path's setup in the same manner for either handover. The scheme provides forward handover when the radio propagation conditions
deteriorate unpredictably. This paper also shows sequences of call origination, connection pre-establishment, and route-change
in our proposed scheme, and illustrates operation of the CCS and the ATM switches.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
153.
Matsunaga K Kindaichi T Ozaki N Ohashi A Nakahara Y Sasakawa M 《Water science and technology》2012,66(2):451-456
In up-flow anammox reactors, one of the contributing factors to biomass wash-out is the adherence of nitrogen gas produced by the anammox reaction to biomass. In this study, we operated an up-flow anammox reactor equipped with a degassing membrane to minimize the biomass wash-out from the reactor by separating the produced gas from the biomass. In addition, both the effect of degassing on the anammox reactor performance and the durability of the membrane submerged in the anammox reactor were investigated. The results show that the use of the degassing membrane in the anammox reactor could (1) improve the biomass retention ability (by separating the produced gas from the biomass), and (2) increase the component ratio of anammox bacteria in the reactor. In addition, degassing could reduce the N(2)O emission produced in the reactor (for the gas selectivity of the degassing membrane). No membrane fouling was observed even after 2 months of operation without washing, indicating an advantage to the use of the degassing membrane. 相似文献
154.
Urinary tract infections (UTI) are the most frequent nosocomial infections of women during puerperium. Since, in these women, diagnostic accuracy is affected by lochial secretion, suprapubic urinary bladder puncture (SPB) is recommended. Between December 1989 and January 1993, we subjected 903 women to suprapubic urinary bladder puncture (SpBP) at the 4th or 5th day after delivery. A urine culture of SpBP was done in all cases. Semiquantitative leukocyte counts (n = 891) and nitrite test (n = 830) were done on mid-stream urine (MSU). Side by side with microbiological investigation for urinary tract pathogens via SpPB, MSU was performed in 246 cases immediately after SpPB had been carried out. Leukocyte counts were also estimated in SpBP urine samples. In 370 (41.1%) of 903 SpBP, one or more microorganisms were cultivated. Only 36 (4.0%) of 903 women showed UTI symptoms. Microorganisms were detectable via SpBP in only 26 (72.7%) of these 36 symptomatic patients. Vaginal-operative or secondary caesarean section are related to an increased UTI rate (p < 0.001). UTI were also significantly (p < 0.0001) more frequent in women subjected to catheterisation sub partu (54.5%) compared to no catheterism (24.4%). No significant differences between the number of leukocytes in MSU sediment and the SpBP findings were seen. Semiquantitative leukocyte counts in SpBP offered a significantly (p < 0.001) increased number of leukocytes in cases with microorganism detection in SpBP irrespective of MSU findings. These results justify the designation of uterine tract infection also in the absence of complaints as "infection" and not common "bacteriuria".(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
155.
Muneharu Kuwata Hiroaki Sugiura Tomohiro Sasagawa Atsushi Michimori Eiich Toide Takayuki Yanagisawa Syuhei Yamamoto Yoshihito Hirano Masahiro Usui Shigenori Teramatsu Jun Someya 《Journal of the Society for Information Display》2009,17(11):875-882
Abstract— A high‐definition laser TV that employs a newly developed laser light source and a super‐wide‐angle projection optical system has been developed. This adoption of a laser light source with three primary colors helped to achieve an extremely wide color gamut, and, in addition, a compact optical engine, which has been optimized to the laser light source and contributed to the achievement of the stylish design of a large screen of 65 in., with the depth being only 255 mm. 相似文献
156.
Coastal sulphur plumes in the upper water layer are frequently observed off the Namibian coast. However, their temporal and spatial development, strength, size and impact on marine life differ at a wide range. This study compares the events of years 2007/2008 to the years 2004/2005 along the Namibian coast, including regional features on the basis of remote sensing satellite data, in situ measurements of a mooring and local observations. The remotely sensed derived intensity of coastal sulphur plumes of year 2008 was very weak compared to 2004 and especially to 2005, the year with the highest activity during the study period. In 2008, the overall maximum of sulphur plumes was observed in February, about 2 months earlier than in 2004 and 2005 when highest intensity was detected in April. Locally, differences in timing and strength of sulphur plumes occurred in the area of the Walvis Bay. There, the maximum intensity was observed in March 2004 and in April 2005, but in 2008 no clear maximum was found. The remotely sensed identified coastal sulphur plumes correlate with periods of low oxygen concentrations in bottom water and high fraction of South Atlantic central water (SACW) at a mooring 20 nautical miles off the central Namibian coast. An exception is the area in the vicinity of the Walvis Bay lagoon that seems to be driven by different local dynamics. The total variability of the sulphur plumes could not be explained by the observed oceanographic conditions alone. Additionally, microbiological and chemical processes in the sediment and the bottom water layer should be included in future investigations related to annual and interannual variability. Disastrous local events were observed in the year 2008 although the averaged intensity was low compared to the years 2004/2005. Therefore, the remotely sensed derived averaged intensity gives probably no real impression of the local impact of sulphur plumes on marine life. A combination of all available methods like the detection by local observations, in situ measurements and remote sensing approaches is required. 相似文献
157.
Yoshiro Nishimura Akinori Takasu Yoshihito Inai Tadamichi Hirabayashi 《应用聚合物科学杂志》2005,97(5):2118-2124
The melt spinning and melt drawing of poly(L ‐lactic acid) (PLLA) were carried out with a melt‐spinning machine, and the mechanical properties, structure, and biodegradability of PLLA fiber were investigated. PLLA fiber with a tensile strength of 0.81 GPa was successfully obtained through two steps of drawing at a draw ratio of 18 in hot water. This fiber had enough tensile strength for common engineering use. The fiber could be degraded under controlled composting conditions at 70°C for 1 week. In scanning electron microscopy observations of the fiber, a regular pattern of cracks running along the vertical direction to the fiber axis was clearly observed. This suggested that the PLLA fiber built up a highly ordered structure arranged along the direction of the fiber axis. After the fiber was left to lie in the ground for 1 year, however, the surface of the fiber was still smooth, and the tensile strength did not decrease much. This PLLA fiber could not be hydrolyzed after 1 month of steeping in a buffer solution at 37°C, but it was rapidly hydrolyzed at more than 60°C. It was suggested that the degradation (hydrolysis) rate of PLLA depended on the glass‐transition temperature. Upon hydrolysis at 80°C for 48 h, a regular crack along the vertical direction to the fiber axis was found that was very similar to that observed in degradation under composting conditions. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 2118–2124, 2005 相似文献
158.
Jun Suzuki Kiminori Gemba Schumpeter Tamada Yoshihito Yasaki Akira Goto 《Scientometrics》2006,68(2):265-288
Summary The paper aims to clarify the extent to which the results of scientific-oriented research conducted by corporations are reflected
in their application-oriented research. Focusing on large Japanese manufacturers of electrical machinery, the paper analyses
firm-level data on presentations of scientific papers that represent the results of scientific-oriented research activities,
citations of scientific papers in patents, and inventions. The electrical machinery industry, a prototypical science-based
industry, has been placing a growing emphasis on scientific-oriented research during the 1990's as is evident from trends
in R&D expenses, scientific papers, and inventions. Regression analysis results suggest a complementary relationship between
citations of basic scientific knowledge as presented in scientific papers on the one hand and acts of invention on the other
hand, in the sense that a rise in citations corresponds to a rise in inventions. Moreover, the results suggest that invention
efficiency (number of patent claims per unit of R&D expenditure) has been increasing during the 1990's. Furthermore, the results
suggest that, given the exogenous influences on the patent system in Japan, it is necessary to include the number of patent
claims when attempting to measure corporate technology development activity through the volume of patent applications. However,
there was no finding of a clear relationship between the number of scientific papers and inventions. Implications of these
results for corporate R&D strategy are examined. 相似文献
159.
Yoshihito Kurazumi Tadahiro Tsuchikawa Naoki Matsubara Tetsumi Horikoshi 《Building and Environment》2008
The purpose of this paper is to measure the heat transfer areas of the human body and to examine the effect of posture on these values, which is necessary data for calculating heat exchange between the human body and its environment. The total surface area of a subject's body was measured directly. Then, the convective heat transfer area, radiative heat transfer area and conductive heat transfer area were measured for the same subject in 9 postures: standing, chair sitting, seiza sitting, cross-legged sitting, sideways sitting, both-knees-erect sitting, legs-out sitting, lateral position and supine. The ratios of the radiative heat transfer area, convective heat transfer area ratio and conductive heat transfer area to body surface area were as follows: Standing, 0.942, 0.773, 0.013; chair sitting, 0.910, 0.732, 0.008; seiza sitting, 0.853, 0.621, 0.013; cross-legged sitting, 0.843, 0.606, 0.029; sideways sitting, 0.877, 0.634, 0.030; both-knees-erect sitting, 0.865, 0.609, 0.023; legs-out sitting, 0.878, 0.686, 0.038; lateral position, 0.879, 0.712, 0.039; and supine, 0.811, 0.708, 0.100. Posture was shown to have a noticeable effect on the heat transfer areas of the human body. 相似文献
160.
Tanabe Y Yasuda K Azuma C Taniguro H Onodera S Suzuki A Chen YM Gong JP Osada Y 《Journal of materials science. Materials in medicine》2008,19(3):1379-1387
The study evaluated biological reaction of four types of novel double network gels in muscle and subcutaneous tissues, using
implantation tests according to the international guideline. The implantation tests demonstrated that, although poly (2-acrylamide-2-metyl-propane
sulfonic acid)/poly (N,N′-dimetyl acrylamide) (PAMPS/PDMAAm) gel induced a mild inflammation at 1 week, the degree of the inflammation significantly
decreased into the same degree as that of the negative control at 4 and 6 weeks. This gel has a potential to be applied as
artificial cartilage. In addition, Cellulose/Gelatin gel showed the same degree of inflammation as that of the negative control
at 1 week, and then, showed a gradually absorbable property at 4 and 6 weeks. This gel has a potential to be applied as an
absorbable implant. The PAMPS/polyacrylamide and Cellulose/PDMAAm gels induced a significant inflammation at each week. These
DN gels are difficult to be applied as clinical implants in the current situation. 相似文献