88 research outputs found
Ultra-broad band perfect absorption realized by phonon-photon resonance in periodic polar dielectric material based pyramid structure
In this research, a mid-infrared wide-angle ultra-broadband perfect absorber
which composed of pyramid grating structure has been comprehensively studied.
The structure was operated in the reststrahlem band of SiC and with the
presence of surface phonon resonance(SPhR), the perfect absorption was observed
in the region between 10.25 and 10.85 . We explain the mechanism of this
structure with the help of PLC circuit model due to the independence of
magnetic polaritons. More over, by studying the resonance behavior of different
wavelength, we bridged the continuous perfect absorption band and the discret
peak in 11.05 (emerge two close absorption band together) by
modification of the geometry. The absorption band has been sufficiently
broadened. More over, both 1-D and 2-D periodic structure has been considered
and the response of different incident angles and polarized angles have been
studied and a omnidirectional and polarization insensitive structure can be
realized which may be a candidate of several sensor applications in
meteorology. The simulation was conducted by the Rigorous Coupled Wave
Method(RCWA)
Symmetry TFTs for Non-Invertible Defects
Given any symmetry acting on a -dimensional quantum field theory, there is
an associated -dimensional topological field theory known as the
Symmetry TFT (SymTFT). The SymTFT is useful for decoupling the universal
quantities of quantum field theories, such as their generalized global
symmetries and 't Hooft anomalies, from their dynamics. In this work, we
explore the SymTFT for theories with Kramers-Wannier-like duality symmetry in
both d and d quantum field theories. After constructing the
SymTFT, we use it to reproduce the non-invertible fusion rules of duality
defects, and along the way we generalize the concept of duality defects to
\textit{higher} duality defects. We also apply the SymTFT to the problem of
distinguishing intrinsically versus non-intrinsically non-invertible duality
defects in d.Comment: 119 pages, 46 figures; v2: references added, typos corrected; v3:
publication versio
School-age population and educational planning in China
This study has projected, compared and analysed
the trends in size of the total population, school-going
population (aged 6-14) and level of school enrollment
under various fertility assumptions for China during the
period 1982-2012, as well as associated demands. The
focus of this study is on the future school enrollment
and its implications. Based on population projections by
residence (rural and urban), under different mortality
and fertility assumptions, this study has found that in
general the size of the projected school-age population
aged 6-14 and school enrollment for primary and junior
high school show a falling trend broken by a substantial
period of increase during the period 1982-2012, but the
dimension of changes is varied under different fertility
variants. With the passage of time, the differences
among the projected results under different fertility
variants become larger as a result of the intensified
influence of fertility assumptions.
Taking the projection results under the medium
variant as an example, it is found that the school-going
population decreases by 23 per cent during the period
1982-1992 for rural areas and by 32 per cent during the
period 1982-1999 for urban areas; and increases by 35
per cent during 1992-2005 for rural areas and increase by
less than 0.01 during the period 1999-2001 for urban
areas; then decreases again starting from 2006 and 2002
to the end of the projection period for rural and urban areas respectively. It is further assumed that the
enrollment rate will increase from 87.6 per cent in 1982
to about 99.8 per cent in 2002 for urban areas and from
73.1 per cent in 1982 to about 99.5 per cent in 2012 for
rural areas, indicating the realization of a universal
period of nine years of compulsory education.
Correspondingly, a similar fluctuation occurs to the
associated demands for teachers and funds.
This study has also examined and evaluated some
of the implications of the fluctuation of the projected
trends of school-going population. Although the policy
of population growth control will benefit the people's
well-being and the national development, including the
development of education, this kind of fluctuation in the
population trends that will result from the
implementation of the inconsistent population policy in
the past must be taken into serious consideration by the
policy-makers and education-planners. Flexible and
appropriate strategies should be implemented in advance,
for such aspects as the training of qualified teaching
staff and available funds, in order to accommodate the
future fluctuations in the demand for educational
services
Transcriptome And Expression Profiling Analysis Link Patterns Of Gene Expression To Antennal Responses In Spodoptera Litura
Background: The study of olfaction is key to understanding the interaction of insects with their environment and provides opportunities to develop novel tactics for control of pest species. Recent developments in transcriptomic approaches enable the molecular basis of olfaction to be studied even in species with limited genomic information. Here we use transcriptome and expression profiling analysis to characterize the antennal transcriptome of the noctuid moth and polyphagous pest Spodoptera litura. Results: We identify 74 candidate genes involved in odor detection and recognition, encoding 26 ORs, 21 OBPs, 18 CSPs and 9 IRs. We examine their expression levels in both sexes and seek evidence for their function by relating their expression with levels of EAG response in male and female antennae to 58 host and non-host plant volatiles and sex pheromone components. The majority of olfactory genes showed sex-biased expression, usually male-biased in ORs. A link between OR gene expression and antennal responses to odors was evident, a third of the compounds tested evoking a sex-biased response, in every case also male-biased. Two candidate pheromone receptors, OR14 and OR23 were especially strongly expressed and male-biased and we suggest that these may respond to the two female sex pheromone components of S. litura, Z9E11-14:OAc and Z9E12-14:OAc, which evoked strongly male-biased EAG responses. Conclusions: Our results provide the molecular basis for elucidating the olfactory profile of moths and the sexual divergence of their behavior and could enable the targeting of particular genes, and behaviors for pest management
Association of vitamin D with HIV infected individuals, TB infected individuals, and HIV-TB co-infected individuals: a systematic review and meta-analysis
BackgroundVitamin D deficiency (VDD) is a worldwide disease. VDD is also associated with an increased risk of HIV-related comorbidities and mortality, and patients have a tendency to develop active tuberculosis compared to those with latent tuberculosis infection. Vitamin D supplementation may modulate HIV replication, improve TB inflammation and reduce progression of HIV-TB co-infection.MethodsWe meta-analyzed individual participant data from cohort studies, cross-sectional study, and RCTs of vitamin D in HIV group, TB group, and HIV-TB group. The primary outcomes were differences in vitamin D level and VDD prevalence between three groups, the secondary outcomes were CD4 count, HIV viral load, time to sputum smear conversion, time to culture conversion, relapse, morality, and TB score.ResultsFor vitamin D levels, the overall mean difference (MD) between HIV group and TB group was β0.21 (95% CI, β20.80β20.38; pβ=β0.9, I2β=β84%), HIV group and HIV-TB group was 0.87 (95% CI, β11.45β13.20; pβ=β0.89, I2β=β87%), and TB group and HIV-TB group was 1.17 (95% CI, β5.21β7.55; pβ=β0.72, I2β=β85%). For vitamin D deficiency prevalence, the overall odds ratio (OR) for HIV group versus TB group was 1.23 (95% CI, 0.46β3.31; pβ=β0.68; I2β=β70%), HIV group versus HIV-TB group was 1.53 (95% CI, 1.03β2.29; pβ=β0.04; I2β=β0%), and TB group versus HIV-TB group was 0.85 (95% CI, 0.61β1.20; pβ=β0.36; I2β=β22%). In HIV-TB group, the overall OR for vitamin D group versus placebo group was 0.78 (95% CI, 0.34β1.67; pβ=β0.52; I2β=β60%).ConclusionOur findings indicated that there were no variations in vitamin D levels between three groups. The prevalence of vitamin D deficiency was higher in the HIV-TB group than in the HIV group. Additionally, the administration of vitamin D supplements did not have obvious impact on CD4 count and viral load. Likewise, vitamin D had no effect on time to sputum smear conversion, time to culture conversion, relapse, 12-month morality, and TB score
An Optimization Control Method of IEH Considering User Thermal Comfort
In this paper, a user thermal comfort criterion based on predicted mean vote (PMV) values is introduced to realize the optimal operation of an improved energy hub (IEH) while considering thermal inertia and user thermal behavior. A three-layer optimization model based on user thermal comfort is constructed which fully considers user thermal comfort demand, IEH operating costs, and energy network constraints. Moreover, since IEH optimization considering user thermal comfort is a multi-objective bilevel optimization (MNBO) problem, this paper proposes an improved multilayer nested quantum genetic algorithm (IMNQGA) to solve it. Finally, the effectiveness of the proposed optimization model and algorithm is verified through the analysis of the four modes. The examples show that the proposed optimal control method can reduce the systemβs operating costs and improve energy efficiency while satisfying user thermal comfort demand
Multi-scale perimeter control approach in a connected-vehicle environment
This paper proposes a novel approach to integrate optimal control of perimeter intersections (i.e. to minimize local delay) into the perimeter control scheme (i.e. to optimize traffic performance at the network level). This is a complex control problem rarely explored in the literature. In particular, modeling the interaction between the network level control and the local level control has not been fully considered. Utilizing the Macroscopic Fundamental Diagram (MFD) as the traffic performance indicator, we formulate a dynamic system model, and design a Model Predictive Control (MPC) based controller coupling two competing control objectives and optimizing the performance at the local and the network level as a whole. To solve this highly non-linear optimization problem, we employ an approximation framework, enabling the optimal solution of this large-scale problem to be feasible and efficient. Numerical analysis shows that by applying the proposed controller, the protected network can operate around the desired state as expressed by the MFD, while the total delay at the perimeter is minimized as well. Moreover, the paper sheds light on the robustness of the proposed controller. This multi-scale hybrid controller is further extended to a stochastic MPC scheme, where connected vehicles (CV) serve as the only data source. Hence, low penetration rates of CVs lead to strong noises in the controller. This is a first attempt to develop a network-level traffic control methodology by using the emerging CV technology. We consider the stochasticity in traffic state estimation and the shape of the MFD. Simulation analysis demonstrates the robustness of the proposed stochastic controller, showing that efficient controllers can indeed be designed with this newly-spread vehicle technology even in the absence of other data collection schemes (e.g. loop detectors).ISSN:2352-146
Non-Invertible Symmetries of SYM and Twisted Compactification
Non-invertible symmetries have recently been understood to provide
interesting contraints on RG flows of QFTs. In this work, we show how
non-invertible symmetries can also be used to generate entirely new RG flows,
by means of so-called "non-invertible twisted compactification". We illustrate
the idea in the example of twisted compactifications of 4d
super-Yang-Mills (SYM) to three dimensions. After giving a catalogue of
non-invertible symmetries descending from Montonen-Olive duality
transformations of 4d SYM, we show that twisted
compactification by non-invertible symmetries can be used to obtain 3d
theories which appear otherwise unreachable if one restricts to
twists by invertible symmetries.Comment: 53 pages, 12 figures, 18 table
Multi-scale perimeter control approach in a connected-vehicle environment
This paper proposes a novel approach to integrate optimal control of perimeter intersections (i.e. to minimize local delay) into the perimeter control scheme (i.e. to optimize traffic performance at the network level). This is a complex control problem rarely explored in the literature. In particular, modeling the interaction between the network level control and the local level control has not been fully considered. Utilizing the Macroscopic Fundamental Diagram (MFD) as the traffic performance indicator, we formulate a dynamic system model, and design a Model Predictive Control (MPC) based controller coupling two competing control objectives and optimizing the performance at the local and the network level as a whole. To solve this highly non-linear optimization problem, we employ an approximation framework, enabling the optimal solution of this large-scale problem to be feasible and efficient. Numerical analysis shows that by applying the proposed controller, the protected network can operate around the desired state as expressed by the MFD, while the total delay at the perimeter is minimized as well. Moreover, the paper sheds light on the robustness of the proposed controller. This multi-scale hybrid controller is further extended to a stochastic MPC scheme, where connected vehicles (CV) serve as the only data source. Hence, low penetration rates of CVs lead to strong noises in the controller. This is a first attempt to develop a network-level traffic control methodology by using the emerging CV technology. We consider the stochasticity in traffic state estimation and the shape of the MFD. Simulation analysis demonstrates the robustness of the proposed stochastic controller, showing that efficient controllers can indeed be designed with this newly-spread vehicle technology even in the absence of other data collection schemes (e.g. loop detectors).ISSN:2352-146
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