6,496 research outputs found
Filtering antenna with two-octave harmonic suppression
A novel 2nd–order antenna with filtering performance and two-octave harmonic suppression is proposed. In order to reduce the effects of the harmonics of the antenna, two types of antennas (PIFA and patch) with different resonant characteristics are integrated into the design. Compared with the traditional patch antennas, this integrated work can not only eliminate the high-order harmonics of the antenna but also improve the in-band bandwidth and frequency selectivity. The 2nd and 4th–order harmonics of the patch are suppressed because of the detuned harmonic performance of the PIFA and patch. The 3rd-order harmonic is eliminated by integrating notch resonators in the PIFA. A prototype works at 2.4 GHz is developed to demonstrate the PIFA-patch integration scheme. Measured and simulated results of antennas agree well with each other, demonstrating good performance of bandwidth, 2nd-order filtering, radiation and wideband harmonic suppression (up to 11 GHz)
SCA-PVNet: Self-and-Cross Attention Based Aggregation of Point Cloud and Multi-View for 3D Object Retrieval
To address 3D object retrieval, substantial efforts have been made to
generate highly discriminative descriptors of 3D objects represented by a
single modality, e.g., voxels, point clouds or multi-view images. It is
promising to leverage the complementary information from multi-modality
representations of 3D objects to further improve retrieval performance.
However, multi-modality 3D object retrieval is rarely developed and analyzed on
large-scale datasets. In this paper, we propose self-and-cross attention based
aggregation of point cloud and multi-view images (SCA-PVNet) for 3D object
retrieval. With deep features extracted from point clouds and multi-view
images, we design two types of feature aggregation modules, namely the
In-Modality Aggregation Module (IMAM) and the Cross-Modality Aggregation Module
(CMAM), for effective feature fusion. IMAM leverages a self-attention mechanism
to aggregate multi-view features while CMAM exploits a cross-attention
mechanism to interact point cloud features with multi-view features. The final
descriptor of a 3D object for object retrieval can be obtained via
concatenating the aggregated features from both modules. Extensive experiments
and analysis are conducted on three datasets, ranging from small to large
scale, to show the superiority of the proposed SCA-PVNet over the
state-of-the-art methods
Sustainable Solution for Shoring Method of Cross-Creek Bridge in Ankeng MRT System in New Taipei City: A Case Study
In the Ankeng Light Rail MRT system (ALRMS) project, the U7 box girder passes crossing the Erbads creek and needs a temporary supporting system for the construction work. In this study, three temporary shoring system options were proposed to be the construction method. The D-B Contractor, New Asia construction and Development Corporation, evaluated and selected the optimal choice, The Steel truss frame with supporting beams, to serve as the temporary supporting system. Compare the deflection of Δmax and Δactual, which are 1.609 cm and 1.59 cm, respectively. This result presented that the shoring system composed of the H912*302*18*37 supporting beams and steel truss frame had achieved outstanding performance and work to construct the U7 box girder. This paper presents how the three options are evaluated and the detailed construction processes along with the survey verification for the method
5,6,7-Trichloro-2-methoxy-8-hydroxyquinoline
In the title compound, C10H6Cl3NO2, a mean plane fitted through all non-H atoms has an r.m.s. deviation of 0.035 Å. In the crystal, adjacent molecules are connected by O—H⋯O hydrogen bonds and π–π stacking interactions [centroid–centroid distance = 3.650 (1) Å], resulting in an infinite chain which propagates in the b-axis direction
Tracking the nematicity in cuprate superconductors: a resistivity study under uniaxial pressure
Overshadowing the superconducting dome in hole-doped cuprates, the pseudogap
state is still one of the mysteries that no consensus can be achieved. It has
been suggested that the rotational symmetry is broken in this state and may
result in a nematic phase transition, whose temperature seems to coincide with
the onset temperature of the pseudogap state around optimal doping level,
raising the question whether the pseudogap results from the establishment of
the nematic order. Here we report results of resistivity measurements under
uniaxial pressure on several hole-doped cuprates, where the normalized slope of
the elastoresistivity can be obtained as illustrated in iron-based
superconductors. The temperature dependence of along particular lattice
axis exhibits kink feature at and shows Curie-Weiss-like behavior above
it, which may suggest a spontaneous nematic transition. While seems to
be the same as around the optimal doping and in the overdoped region,
they become very different in underdoped LaSrCuO. Our results
suggest that the nematic order, if indeed existing, is an electronic phase
within the pseudogap state.Comment: 6 pages, 4 figure
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