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101.
Landsiedel Justus Root Waleri Schramm Christian Menzel Alexander Witzleben Steffen Bechtold Thomas Pham Tung 《Nano Research》2020,13(10):2658-2664
Nano Research - Development of colored surfaces by formation of nano-structured aggregates is a widely used strategy in nature to color lightweight structures (e.g. butterflies) without the use of... 相似文献
102.
Alkali‐Assisted Synthesis of Nitrogen Deficient Graphitic Carbon Nitride with Tunable Band Structures for Efficient Visible‐Light‐Driven Hydrogen Evolution 下载免费PDF全文
103.
Photocatalysts: Layered‐Double‐Hydroxide Nanosheets as Efficient Visible‐Light‐Driven Photocatalysts for Dinitrogen Fixation (Adv. Mater. 42/2017) 下载免费PDF全文
104.
There are two methods applied for three-dimensional digital image correlation method to measure three-dimensional displacement. One is to measure the spatial coordinates of measuring points by analyzing the images. Then, the displacement vectors of these points can be calculated using the spatial coordinates of these points obtained at different stages. The other is to calibrate the parameters for individual measuring points locally. Then, the local displacements of these points can be measured directly. This study proposes a simple local three-dimensional displacement measurement method. Without any complicated distortion correction processes, this method can be used to measure small displacement in the three-dimensional space through a simple calibration process. A laboratory experiment and field experiment are carried out to prove the accuracy of this proposed method. Laboratory test errors of one-dimensional experiment are similar to the accuracy of the XYZ table; the error in Z-direction is only 0.0025% of the object distance. The measurement error of laboratory test is about 0.0033% of the object distance for local three-dimensional displacement measurement test. Test and analysis results of field test display that in-plane displacement error is only 0.12 mm, and the out-of-plane error is 1.1 mm for 20 m × 30 m measuring range. The out-of-plane error is only about 10 PPM of the object distance. These test and analysis results show that this proposed method can achieve very high accuracy under small displacement for both of laboratory and field tests. 相似文献
105.
High-ranking officers require advanced military education in war tactics for future combat. However, line officers rarely have time to take such courses on campus. The conventional solution to this problem used to take the inefficient correspondence courses. Whereas Internet technologies progress, online course is the current trend for military training. However, the question is what distance learning methodology best suits such a proprietary learning purpose.This study presents a sequential process of developing distance learning courses in advanced military education. Further, the Petri-Net analytical approach is adopted to discover the essential interaction requirements of advanced military education delivered via Internet. This study developed a systematic method for designing e-learning systems according to specific requirements of target courses. The proposed approach starts by comparing on-campus programs with the existing e-learning systems to identify the steps required to transform the program into an e-learning system. After first outlining the pedagogy of the on-campus program, its proposed teaching flow through the Internet is then sketched. Finally, the Petri-Net model was used for in-depth analysis of the stages affecting the learning curve of the line office taking e-learning courses. The example of a “Joint Operations” AME course elaborated the presented approach. An e-learning system prototype was also designed accordingly. Lastly, an experiment was conducted to verify the efficiency of the presented approach. 相似文献
106.
107.
Performance of DS SS system under on-off wideband jamming 总被引:1,自引:0,他引:1
Xiang Gui Tung Sang Ng 《Electronics letters》1997,33(7):557-559
A performance analysis of a direct sequence spread spectrum (DS SS) system under a periodic on-off wideband jammer is presented. Closed-form results of system bit error rate (BER) are derived for all possible cases of jammer duty cycle 相似文献
108.
This paper reports on fabrication and characterization of a new electrostatic microactuator that achieves out-of-plane multi-axis motion with a single silicon device layer. The multi-axis motion with the simple actuator design is possible by incorporating a three-dimensional (3-D) polydimethylsiloxane (PDMS) microstructure. This paper develops a new device processing method named "Soft-Lithographic Lift-Off and Grafting (SLLOG)" to fabricate the previously designed PDMS-on-silicon hybrid actuator structure. SLLOG is a low-temperature (less than 150/spl deg/C) process that allows replica molded PDMS microstructures to be integrated in silicon micromachined device patterns. The fabricated actuator is characterized using laser vibrometry. The experimental results demonstrate actuation motions achieved in three independent axes with fast dynamic response reaching a bandwidth of about 5 kHz. The fabricated PDMS-on-silicon actuator yields a vertical displacement up to 5 /spl mu/m and rotational motions with a 0.6-/spl deg/ tilting angle at a 40-V peak-to-peak ac actuation voltage. 相似文献
109.
110.
P Mitchell D Hadzi-Pavlovic G Parker I Hickie K Wilhelm H Brodaty P Boyce 《Canadian Metallurgical Quarterly》1996,40(10):941-950
The reactivity of sera of 96 individuals infected with human T-cell leukemia virus type I (HTLV-I) was tested against various synthetic peptides corresponding to the gp46 immunodominant antigenic domains: residues 86-107, 175-199, and 239-261. The frequency of reactive sera was higher for 175-199 (93%) than for 239-261 (78%) or 86-107 (24%) with some variations in geographical regions and in diseases. The region 239-261 was extensively analyzed and five (linear or conformational) epitopes were found. The reactivity of sera toward functional or immunodominant domains may depend on the sequence of the infecting virus, and the role of three frequent substitutions (asparagine by tyrosine, proline by serine, and serine by proline or leucine at positions 93, 192, and 250 respectively) was established. Finally, the role of the genetic background of the host may condition the humoral immune response as individuals infected by HTLV-Is harboring the same predicted gp46 peptide sequence may recognize one, several, or all regions examined. 相似文献