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101.
Beamforming experiment with a DBF multibeam antenna in a mobilesatellite environment 总被引:1,自引:0,他引:1
Miura R. Tanaka T. Chiba I. Horie A. Karasawa Y. 《Antennas and Propagation, IEEE Transactions on》1997,45(4):707-714
This paper describes a digital beamforming (DBF) multibeam antenna that incorporates a compact digital signal processor (DSP) engine, and the results of using it in a beamforming experiment receiving a satellite signal in a land-mobile environment. A considerable reduction in the scale of the DSP engine has been achieved by using field programmable gate arrays (FPGAs). To capture a satellite signal arriving from an unknown direction, a two-dimensional (2-D) spatial FFT signal processing provides orthogonal multibeam patterns on the broad side of a planar array antenna. The experimental results demonstrated the features of coarse acquisition and tracking of a signal arrival by selecting the strongest of the beams without assistance from direction finding sensors or microwave phase shifters. The DBF multibeam antenna will provide high-quality communications and increase traffic capacity if it is applied to high-gain mobile antennas or multispot-beam base station antennas in cellular or satellite mobile communications 相似文献
102.
The melatonin binding sites in membrane preparations of the young mouse thymus were studies using [125I] iodomelatonin as the radioligand. Effect of epinephrine (E) on melatonin receptor (MR) of young mouse thymus were investigated. Results: (1) E had inhibitory effect on MR of mouse thymus; (2) Propranolol could reverse the inhibitory effect of E but phentolamin could not; (3) cAMP had inhibitory effect on MR. These results indicate that E has the inhibitory effect on MR of the mouse thymus and the effect was mediated by beta-adrenergic receptor. 相似文献
103.
Since the early 1960s the Brief Psychiatric Rating Scale (BPRS) has been one of the most frequently used standardized methods in international psychiatric research. The BPRS is used mainly for the rating of psychopathological symptoms of schizophrenic subjects. According to the results of factorial analyses, the original version of the BPRS is divided into five subscales, which have been preserved in the German translation. The validity of this original scale structure for the German BPRS version has not been investigated, however. A principal-components analysis of the 18 BPRS items carried out on the data of 301 schizophrenics yielded four factors that are comparable with four of the original subscales: Thought disturbance, Hostility/suspiciousness, Anxiety/depression, and Anergia. These results are compared with earlier findings and similarities and differences are discussed. 相似文献
104.
The objective of the study is to establish a method for measuring the thickness of thin condensates of liquid mixtures using a laser light absorption method during the process of water–ethanol Marangoni dropwise condensation. First, the extinction property of the test material, with unknown properties related to infrared laser light having a wavelength of 3.39µm, was measured. Next, measurements were made of the variations in condensate film thickness after the sweeping of the heat transfer surface by departing drops in the Marangoni dropwise condensation cycle. The precision of this method was investigated on the basis of the extinction coefficient of the test material and the thickness of the liquid film. Results showed that this method provides good precision and is applicable to the measurement of other similar materials. © 2003 Wiley Periodicals, Inc. Heat Trans Asian Res, 32(8): 700–711, 2003; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.10124 相似文献
105.
An anti-p185HER2/anti-CD3 humanized bispecific diabody was previously constructed from two cross-over single-chain Fv in which YH and VL domains of the parent antibodies are present on different polypeptides. Here this diabody is used to evaluate domain interface engineering strategies for enhancing the formation of functional heterodimers over inactive homodimers. A disulfide-stabilized diabody was obtained by introducing two cysteine mutations, VL L46C and VH D101C, at the anti-p185HER2.VL/VH interface. The fraction of recovered diabody that was functional following expression in Escherichia coli was improved for the disulfide-stabilized compared to the parent diabody (> 96% versus 72%), whereas the overall yield was > 60-fold lower. Eleven "knob-into-hole" diabodies were designed by molecular modeling of sterically complementary mutations at the two VL/VH interfaces. Replacements at either interface are sufficient to improve the fraction of functional heterodimer, while maintaining overall recoverable yields and affinity for both antigens close to that of the parent diabody. For example, diabody variant v5 containing the mutations VL Y87A:F98M and VH V37F:L45W at the anti-p185HER2 VL/VH interface was recovered as 92% functional heterodimer while maintaining overall recovered yield within twofold of the parent diabody. The binding affinity of v5 for p185HER2 extracellular domain and T cells is eightfold weaker and twofold stronger than for the parent diabody, respectively. Domain interface remodeling based upon either sterically complementary mutations or interchain disulfide bonds can facilitate the production of a functional diabody heterodimer. This study expands the scope of domain interface engineering by demonstrating the enhanced assembly of proteins interacting via two domain interfaces. 相似文献
106.
Katsuto Shimizu Raul Ponce-Hernandez Oumer S. Ahmed Tetsuji Ota Zar Chi Win Nobuya Mizoue 《International journal of remote sensing》2016,37(16):3655-3674
In this study, we evaluated the effects of topographic correction and gap filling of Landsat Enhanced Thematic Mapper Plus (ETM+) images on the accuracy of forest change detection through a trajectory-based approach. Four types of Landsat time series stacks (LTSS) were generated. These stacks resulted from combinations of topographically corrected and uncorrected imagery combined with gap-filled and unfilled stacks. These combinations of stacks were then used as input into a trajectory-based change detection. The results of change detection from trajectory-based analysis using these LTSS were compared in order to assess the effects of both topographic correction and gap-filling procedures on the ability to detect forest disturbances. The results showed that overall accuracies of change detection were improved after gap filling (10.5% and 7.5%), but were only slightly improved after topographic correction (3.6% and 0.6%). Although the gap-filling process introduced some uncertainty that might have caused false change detection, the number of pixels whose detection of disturbance was enhanced after gap filling exceeded those detecting false change. The results also showed that the topographic correction did not contribute much to improve the change detection in this study area. However, topographic correction has a potential to increase the accuracy of change detection in areas of more rugged terrain and steep slopes. This is because a direct relationship between the slope of the topography with topographic correction and an enhanced detection of disturbance in pixels from year to year was observed in this study. For robust change detection, we recommend that a gap-filling process should be included in the trajectory-based analysis procedures such as the one used in this study where a single image per year is used to characterize change. We also recommend that in areas of rugged terrain, a topographic correction in the image pre-processing should be implemented. 相似文献
107.
Highly reliable mobile liquid crystal display using AlOx deposited by atomic layer deposition for side sealing structure 下载免费PDF全文
Tetsuji Ishitani Daisuke Kubota Masaru Nakano Yusuke Kubota Koji Moriya Akio Yamashita Yujiro Sakurada Koji Kusunoki Hideaki Shishido Kazuya Sugimoto Yoshiharu Hirakata Shunpei Yamazaki Masahiko Hayakawa 《Journal of the Society for Information Display》2015,23(11):503-509
A side sealing structure including, outside a sealant, AlOx deposited using an atomic layer deposition apparatus was employed for a low‐frequency driving liquid crystal display (LCD) with a bezel width of 0.7 mm. This side‐sealing structure can effectively prevent the entry of external moisture. Prevention of decrease in voltage‐holding ratio was confirmed with a test cell having this structure. A narrow‐bezel LCD with c‐axis‐aligned a‐b‐plane‐anchored crystal In‐Ga‐Zn Oxide backplane can have long‐term high reliability as a low‐frequency driving LCD. 相似文献
108.
Takeshi ShimomuraAuthor Vitae Tetsuji ItohAuthor VitaeTouru SumiyaAuthor Vitae Taka-aki HanaokaAuthor VitaeFujio MizukamiAuthor Vitae Masatoshi OnoAuthor Vitae 《Sensors and actuators. B, Chemical》2011,153(2):361-368
Laccase was immobilized in mesoporous silica powder with a 7.0 nm pore diameter (FSM7.0) coated onto a glassy carbon electrode using an electrophoretic deposition technique, and the electrode was then applied to the amperometric detection of catechol, which is a typical phenolic compound. The behavior of a biosensor attached to the electrode was examined in terms of pH, applied potential, sensitivity and operational range, selectivity, and storage stability. The sensor showed an optimum response at a pH of 5.0 and at an applied potential of −50 mV. The determination range and the response time for catechol were 2.0-100 μM and approximately 2 min, respectively. In addition, the sensor was quite stable and retained its initial response without notable change after being stored for over 50 days. This result suggests that our method is quite useful for the fabrication of a high-performance biosensor for practical use. 相似文献
109.
This paper presents the development of an alternating method for the interaction analysis of arbitrary distributed numerous
elliptical microcracks. The complete analytical solutions (VNA solutions) for a single elliptical crack in an infinite solid,
subject to arbitrary crack-face tractions, are implemented in the present alternating method, together with the coordinate
transformations for stress tensors. First, the present method is verified by solving the problems of two interacting cracks
for which accurate numerical solutions have been obtained previously. Next, the present method demonstrates obtaining efficient
and accurate solutions for the problems of many interacting elliptical cracks, which cannot be solved in a practical sense
by the ordinary numerical methods such as the finite element method. Furthermore, damaged solids containing periodically distributed
elliptical microcracks are analyzed by the present alternating method. The effective elastic moduli are evaluated for varying
microcrack density. Detailed structures of the interactions in the damaged solids are visualized and clarified.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
110.
Kimihiro Nogiwa Takashi Onitsuka Teruyoshi Abe Yasuhide Sakakibara Kaoru Horie Takahisa Nakamura 《Journal of Nuclear Science and Technology》2013,50(9):883-890
The influence of thermal aging on cast stainless steels used in JAEA's advanced thermal prototype reactor “Fugen” that were exposed to 275°C for about 15 years was investigated. The degree and mechanism of thermal embrittlement were evaluated on the basis of Charpy impact test results and the three-dimensional atom probe (3DAP) analysis of the microstructural changes in the spinodal decomposition using materials obtained from Fugen. The results revealed early signs of a thermal aging effect over a long period at the low temperature. 相似文献