A way to construct the natural representation of the quantized affine algebra
U
v
(
s
l
̂
l
)
is via the deformed Fock space by Misra and Miwa. This relates the classes of Weyl modules for
U
q
(
s
l
...N
)
were
q
is a root of unity to the action of
U
v
(
s
l
̂
l
)
as N tends toward infinity. In this paper we investigate the situation outside of type A. In classical types, we construct embeddings of the Grothendieck group of finite dimensional
U
q
(
g
)
-modules into Fock spaces of different charges and define an action of an affine quantum symmetric pair that plays the role of the quantized affine algebra. We describe how the action is related to the linkage principal for quantum groups at a root of unity and tensor product multiplicities.
The natural representation of the quantized affine algebra of type A can be defined via the deformed Fock space by Misra and Miwa. This relates the classes of Weyl modules for a type A quantum group ...at a root of unity to the action of the quantized affine algebra as the rank tends towards infinity. In this paper we investigate the situation outside of type A. In classical types, we construct embeddings of the Grothendieck group of finite dimensional modules for the corresponding quatum group at a root of unity into Fock spaces of different charges and define an action of an affine quantum symmetric pair that plays the role of the quantized affine algebra. We describe how the action is related to the linkage principal for quantum groups at a root of unity and tensor product multiplicities.
Background:
Magnetically controlled capsule endoscopy (MCCE) is a non-invasive, painless, comfortable, and safe equipment to diagnose gastrointestinal diseases (GID), partially overcoming the ...shortcomings of conventional endoscopy and wireless capsule endoscopy (WCE). With advancements in technology, the main technical parameters of MCCE have continuously been improved, and MCCE has become more intelligent.
Objectives:
The aim of this systematic review was to summarize the research progress of MCCE and artificial intelligence (AI) in the diagnosis and treatment of GID.
Data Sources and Methods:
We conducted a systematic search of PubMed and EMBASE for published studies on GID detection of MCCE, physical factors related to MCCE imaging quality, the application of AI in aiding MCCE, and its additional functions. We synergistically reviewed the included studies, extracted relevant data, and made comparisons.
Results:
MCCE was confirmed to have the same performance as conventional gastroscopy and WCE in detecting common GID, while it lacks research in detecting early gastric cancer (EGC). The body position and cleanliness of the gastrointestinal tract are the main factors affecting imaging quality. The applications of AI in screening intestinal diseases have been comprehensive, while in the detection of common gastric diseases such as ulcers, it has been developed. MCCE can perform some additional functions, such as observations of drug behavior in the stomach and drug damage to the gastric mucosa. Furthermore, it can be improved to perform a biopsy.
Conclusion:
This comprehensive review showed that the MCCE technology has made great progress, but studies on GID detection and treatment by MCCE are in the primary stage. Further studies are required to confirm the performance of MCCE.
Nowadays corrosion has become an urgent problem to be solved. Scientists are committed to finding various ways to restrain the corrosion of metals. The anticorrosion coating is considered to be an ...economical and effective method. However, the conventional anticorrosion coating is vulnerable to be damaged. The external self-healing coating can release the active healing agent when destroyed and prevent the corrosion spontaneously, which has been the subject of increasing interest. In this paper, the anticorrosion application of external self-healing coatings was described in detail, including organic micro/nanocontainer-based, inorganic micro/nanocontainer-based, and microvascular network-based self-healing coatings. First, the present article introduced the development, preparation, and self-healing properties of the external self-healing coating. In the successive chapter, the anticorrosion performance of the coating was highlighted. Also, some open problems and future challenges were also investigated. Finally, special attention was dedicated to the prospect of the external self-healing coating. This review provides readers with an overview of achievements to date and insights into the future development of engineering applications to promote the large-scale application of external self-healing anticorrosion coatings.
Growing global data traffic requires high-performance modulators with a compact size, a large bandwidth, a low optical loss, and a small power consumption. A careful trade-off among these parameters ...usually has to be made when designing such a device. Here, we propose and demonstrate an electro-optic ring modulator on the thin-film lithium niobate platform without compromising between any performances. The device exhibits a low on-chip loss of about 0.15 dB with a high intrinsic quality-factor (Q-factor) of
7.7
×
10
5
. Since a pure coupling modulation is employed, the photon lifetime is no longer a limiting factor for the modulation speed. A large electro-optic bandwidth is obtained without any roll-off up to 67 GHz. The device, with a footprint of
3.4
m
m
×
0.7
m
m
, also exhibits a low half-wave voltage of 1.75 V, corresponding to a half-wave voltage length product of
0.35
V
⋅
c
m
considering the 2-mm-long modulation section. Driverless data transmission up to 240 Gb/s is also demonstrated with a peak-to-peak driving voltage of 0.75 V.
Thin-film lithium niobate (TFLN) based traveling-wave modulators maintain simultaneously excellent performances, including large modulation bandwidth, high extinction ratio, low optical loss, and ...high modulation efficiency. Nevertheless, there still exists a balance between the driving voltage and modulation bandwidth. Here, we demonstrate an ultra-large bandwidth electro-optic modulator without compromising the driving voltage based on the TFLN platform on a silicon substrate, using a periodic capacitively loaded traveling-wave electrode. In order to compensate the slow-wave effect, an undercut etching technique for the silicon substrate is introduced to decrease the microwave refractive index. Our demonstrated devices represent both low optical and low microwave losses, which leads to a negligible optical insertion loss of 0.2 dB and a large electro-optic bandwidth with a roll-off of 1.4 dB at 67 GHz for a 10 mm-long device. A low half-wave voltage of 2.2 V is also achieved. Data rates up to 112 Gb s−1 with PAM-4 modulation are demonstrated. The compatibility of the proposed modulator to silicon photonics facilitates its integration with matured silicon photonic components using, e.g., hybrid integration technologies.
Many countries are facing the increasing cost of healthcare services and the low efficiency of public hospitals. These issues are also evident in China. This paper offers a comprehensive assessment ...of the efficiency of public hospitals operating in China's 31 regions. The impact of the third round of reform of the health system in 2009 is assessed based on the three-stage data envelopment analysis procedure. The time period from 2011 to 2018 is covered in this study. Due to different functions performed by the public hospitals and other ones, the number of patients with infectious diseases is incorporated as an output variable reflecting the social function. The outpatient visits and inpatient visits are considered to reflect the outputs related to the private functions. The results imply an increase in the mean efficiency of public hospitals from 0.927 to 0.981 after taking the impact of environmental variables and statistic noise into account. These results indicate that the efficiency of public hospitals is dependent in the operational environment. There are 11 regions whose hospitals operate on the efficiency frontier during the whole period covered. Therefore, the Chinese government should reasonably design and apply the regulatory tools to improve the efficiency of public hospitals.
For high-temperature, sand-bearing, and high-pressure water injection pipelines, failure of commonly used organic epoxy coatings occurs frequently, which needs to be solved urgently. Ceramic coating ...is excellent alternative to solve this problem, attributed to its high hardness, high temperature resistance, and corrosion resistance. However, ceramic coatings prepared till date suffer from some problems, such as high porosity, and poor toughness. To improve overall performance of composite ceramic coating, herein, ceramic-lined composite steel pipes were synthesized by centrifugal self-propagating high-temperature synthesis (centrifugal-SHS), via doping different concentrations of SiO2 in the Al/Fe2O3 reaction system. The microstructure and phase of composite ceramic coatings after addition of SiO2 were analyzed by optical microscopy with super depth of focus, scanning electron microscopy, energy dispersive spectroscopy, and X-ray diffraction. Effects of SiO2 on the density and porosity, microhardness and fracture toughness, compression-shear strength and crushing strength of composite ceramic coatings were investigated by Archimedes method, Vickers indentation microfracture method, shearing test, and squeezing test, respectively. Results showed that the introduction of appropriate amount of SiO2 reduced cooling rate of reaction system, thus improving the densification level and strength of coatings. Furthermore, in reaction system, FeAl2O4 phase disappeared, owing to excessive Al, which could improve corrosion resistance of composite ceramic coatings. The optimum doping concentration of SiO2 was found to be 4 wt%, in which composite ceramic coating showed excellent properties.
As ferroelectric materials, lithium tantalate and lithium niobate share similar material characteristics, such as a high Pockels effect and nonlinear optical coefficients. When compared to lithium ...niobate, lithium tantalate offers a higher optical damage threshold, a broader transparent window, and lower birefringence, making it a promising candidate for high-performance electro-optical photonic integrated devices. In this study, we design and successfully fabricate micro-ring resonators on an acoustic-grade lithium-tantalate-on-insulator wafer, demonstrating their tunability and dynamic modulation capabilities. Experimental results indicate that the achieved thin-film lithium tantalate based micro-ring resonator exhibits an intrinsic Q-factor of 8.4 × 105, corresponding to a waveguide propagation loss of 0.47 dB/cm and a tuning efficiency of 1.94 pm/V. More importantly, as compared to those based on thin-film lithium niobate, a much weaker photorefractive effect and drift phenomenon around the 1550 nm wavelength under a direct-current drive are observed in the present fabricated thin-film lithium tantalate micro-rings with a silicon oxide over-cladding and a tuning electrode on top.
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