462 research outputs found
Effects of practical impairments on cooperative distributed antennas combined with fractional frequency reuse
Cooperative Multiple Point (CoMP) transmission aided Distributed Antenna Systems (DAS) are proposed for increasing the received Signal-to-Interference-plus-Noise-Ratio (SINR) in the cell-edge area of a cellular system employing Fractional Frequency Reuse (FFR) in the presence of realistic imperfect Channel State Information (CSI) as well as synchronisation errors between the transmitters and the receivers. Our simulation results demonstrate that the CoMP aided DAS scenario is capable of increasing the attainable SINR by up to 3dB in the presence of a wide range of realistic imperfections
Analysis and design of distributed antenna aided twin-layer femto-and macro-cell networks relying on fractional frequency-reuse
Distributed Antenna Systems (DAS) and femtocells are capable of improving the attainable performance in the cell-edge area and in indoor residential areas, respectively. In order to achieve a high spectral efficiency, both the Distributed Antenna Elements (DAEs) and Femtocell Base Stations (FBSs) may have to reuse the spectrum of the macrocellular network. As a result, the performance of both outdoor macrocell users and indoor femtocell users suffers from Co-Channel Interference (CCI). Hence in this paper, heterogenous celluar networks are investigated, where the DAS-aided macrocels and femtocells co-exist within the same area
Exchanging Dual Encoder-Decoder: A New Strategy for Change Detection with Semantic Guidance and Spatial Localization
Change detection is a critical task in earth observation applications.
Recently, deep learning-based methods have shown promising performance and are
quickly adopted in change detection. However, the widely used multiple encoder
and single decoder (MESD) as well as dual encoder-decoder (DED) architectures
still struggle to effectively handle change detection well. The former has
problems of bitemporal feature interference in the feature-level fusion, while
the latter is inapplicable to intraclass change detection and multiview
building change detection. To solve these problems, we propose a new strategy
with an exchanging dual encoder-decoder structure for binary change detection
with semantic guidance and spatial localization. The proposed strategy solves
the problems of bitemporal feature inference in MESD by fusing bitemporal
features in the decision level and the inapplicability in DED by determining
changed areas using bitemporal semantic features. We build a binary change
detection model based on this strategy, and then validate and compare it with
18 state-of-the-art change detection methods on six datasets in three
scenarios, including intraclass change detection datasets (CDD, SYSU),
single-view building change detection datasets (WHU, LEVIR-CD, LEVIR-CD+) and a
multiview building change detection dataset (NJDS). The experimental results
demonstrate that our model achieves superior performance with high efficiency
and outperforms all benchmark methods with F1-scores of 97.77%, 83.07%, 94.86%,
92.33%, 91.39%, 74.35% on CDD, SYSU, WHU, LEVIR-CD, LEVIR- CD+, and NJDS
datasets, respectively. The code of this work will be available at
https://github.com/NJU-LHRS/official-SGSLN
System Identification Algorithm Analysis of Acupuncture Effect on Mean Blood Flux of Contralateral Hegu Acupoint
Background. Acupoints (belonging to 12 meridians) which have the same names are symmetrically distributed on the body. It has been proved that acupoints have certain biological specificities different from the normal parts of the body. However, there is little evidence that acupoints which have the same name and are located bilaterally and symmetrically have lateralized specificity. Thus, researching the lateralized specificity and the relationship between left-side and right-side acupuncture is of special importance. Methodology and Principal Findings. The mean blood flux (MBF) in both Hegu acupoints was measured by Moor full-field laser perfusion imager. With the method of system identification algorithm, the output distribution in different groups was acquired, based on different acupoint stimulation and standard signal input. It is demonstrated that after stimulation of the right Hegu acupoint by needle, the output value of MBF in contralateral Hegu acupoint was strongly amplified, while after acupuncturing the left Hegu acupoint, the output value of MBF in either side Hegu acupoint was amplified moderately. Conclusions and Significance. This paper indicates that the Hegu acupoint has lateralized specificity. After stimulating the ipsilateral Hegu acupoint, symmetry breaking will be produced in contrast to contralateral Hegu acupoint stimulation
Vibronic fine structure in the nitrogen 1s photoelectron spectra from Franck-Condon simulations II: Indoles
The vibronic coupling effect in nitrogen 1s X-ray photoelectron spectra (XPS)
was systematically studied for a family of 17 bicyclic indole molecules by
combining Franck-Condon simulations (including the Duschinsky rotation effect)
and density functional theory. The simulated vibrationally-resolved spectra of
4 molecules agree well with available experiments. Reliable predictions for
this family further allowed us to summarize rules for spectral evolution in
response to three types of common structural changes (side chain substitution,
CHN replacement, and isomerization). Interestingly, vibronic
properties of amine and imine nitrogen are clearly separated: they show
negative and positive ZPE (zero-point vibration energy of the
core-ionized with respect to the ground state), respectively, indicating
flatter and steeper PESs induced by the N 1s ionization; amine N's show
stronger mode mixing effects than imine N's; the 1s ionizations on two types of
nitrogens led to distinct changes in local bond lengths and angles. The rules
are useful for a basic understanding of vibronic coupling in this family, and
the precise spectra are useful for future reference and data mining studies
Laparoscopic surgery for intestinal obstruction in children due to water absorbing gel beads
Introductions: Super absorbent polymer gel bead (SAPGB) is increasingly available as toys for children. When ingested it swells by absorbs water and leads to acute intestinal obstruction. Diagnosis and surgery is challenging as its radiolucent, fragile and slippery. We present outcome of our innovative technique of stabilization and removal SAPGBs by laparoscopy minimal invasive surgery (lap-MIS).
Methods: This retrospective analyse of outcome of lap-MIS in intestinal obstruction caused by ingestion of foreign body, the SAPGBs, in children who were managed at Children's Hospital Affiliated to Zhengzhou University, China. The outcome variables included removal of SAPGBs, length of hospital stay and postoperative occurrence of anastomotic leak, wound infection, wound dehiscence, re-surgery, or mortality.
Results: There were 15 children, male 9 (60%), average age 2 years, and duration of ingestion of SAPGBSs 1.5 days (range 2-4 days), parents gave history of accidental ingestion in 6 (40%). All children had uneventful postoperative recovery after lap-MIS removal of foreign body with no wound infection, anastomotic leak, re-surgery or mortality. Average hospital stay was 4 days (range 3 to 5 days).
Conclusions: We had successful outcome lap-MIS with our innovative technique to stabilize and extract foreign bodies, the super water absorbent gel beads, ingested by children.
Keywords: children, foreign body, gastrointestinal obstruction, laparoscopy minimal invasive surgery, super absorbent polymer gel bead
Isospin Dependence of Nucleon-Nucleon Elastic Cross Section
The in-medium neutron-proton, proton-proton(neutron-neutron) scattering cross
sections(, ) are studied based on QHD-II
type Lagrangian within the framework of the microscopic transport theory. The
results demonstrate that, for free nucleon-nucleon scattering cross sections,
the isospin dependence is dominantly caused by meson field. The medium
correction of nucleon-nucleon scattering cross sections is also isospin
dependent, depends on the baryon density weakly and
depends on the baryon density significantly, which is due
to the different effects of the medium correction of nucleon mass and
meson mass on and , respectivelyComment: PDF fil
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