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With the development of network virtualization technology,the deployment of service function chain in multi-domain network brings new challenges to the optimization of service function chain.The traditional deployment method usually optimizes a single target,which is not suitable for multi-objective optimization,and cannot measure and balance the weight among optimization targets.Therefore,in order to optimize the delay,network load balancing and acceptance rate of large-scale service function chain deployment requests synchronously,a data normalization processing scheme is proposed,and a two-step SFC deployment algorithm based on reinforcement learning is designed.The algorithm takes transmission delay and load balancing as feedback parameters and balances the weight relationship between them,and the SFC acceptance rate is optimized by using reinforcement learning framework simultaneously.The experimental results show that,the delay of the algorithm is reduced by 71.8% compared with LASP method,the acceptance rate is increased by 4.6% compared with MDSP method,and the average load balancing is increased by 39.1% compared with GREEDY method under the large-scale requests.The multi-objective optimization effect is guaranteed.

Intrinsic silicon (Si) is forbidden for infrared (IR) sensing at the communication wavelength like 1.31 or 1.55 µm due to the well‐known bandgap limitation. In this work, an unexpected physical picture of using argon (Ar) is identified, which is usually inert to the surrounding chemical environment and used as a protective agent in semiconductor processing, to overcome the IR‐sensing‐forbidden problem in Si. Here, it is shown by an analysis of a dynamic secondary ion mass spectrometer that such a Si, when exposed to laser pulse in Ar gas, can contain a very high dose of Ar up to 1020 cm−3 even after 1300 days. First‐principles calculations, molecular dynamics, and Hall effect measurements reveal that, due to both steric and dynamic repulsions by Ar orbitals to Si dangling bonds, the Ar‐filled‐vacancy produces a much wider defect band inside the gap, which is not only responsible for strong infrared absorption, but also causes a significant increase in n‐type conductivity, both in line with experiments. The study proves that originally inert elements in fact can act as active impurities in semiconductors for advanced applications, which updates the current knowledge of defect physics. [ABSTRACT FROM AUTHOR]

Aiming at the problem that it is difficult to quickly realize digital modeling due to the large number of parts of the full-pitch stacked winding of large-scale hydroelectric generators and the complex connection logic between the wire bars, this paper proposes a modeling method of full-pitch stacked winding of generators driven by connection logic. Firstly, based on 3D modeling software and the 3D visualization application engine platform, an interactive virtual component model library is constructed. Then, according to the electrical principle of the full-pitch stacked winding, the connection logic is converted into a two-dimensional sequence with clear relationship, so that the winding can be quickly visualized in the virtual scene. Finally, the logic driving model that can be quickly understood by the computer, auxiliary applications such as generator stator winding structure cognition and fault repair is designed. This method shortens the time to construct the 3D model of stator winding, and at the same time, the combination of clear hierarchical equipment tree and 3D visualization model and human-computer interaction interface helps operation and maintenance personnel quickly understand the complex structure of winding and its assembly relationship. [ABSTRACT FROM AUTHOR]

A survivability strategy based on CRDD（conditional risk disjunction degree） in multi-domain optical networks was provided in order to overcome the defect of the scalability constrained and provide differentiated service. The con- cept of CRDD was provided in this strategy, then the intra-domain virtual links reflection was achieved and the end-to-end work route and backup route to differentiate service reliability were computed with CRDD. The results show that the supported survivability strategy not only can differentiate the service reliability, reduce the blocking probability of service, but also can improve reliability for service requirement by 6.5% on average.

Large-flow waste gas generated from the pharmaceutical and chemical industry usually contains low concentrations of VOCs (volatile organic compounds), and it is also the key factor that presents challenges in terms of disposal. To date, due to the limitations of mass transfer rate and microbial degradation ability, the degradation performance of VOCs using the biological method has not been ideal. Therefore, in this study, the sludge from a chlorobenzene-containing wastewater treatment plant was inoculated into our experimental bio-trickling filter (BTF) to explore the feasibility of domestication and degradation of gaseous chlorobenzene by highly active microorganisms. The kinetics of its mass transfer reaction and microbial community dynamics were also discussed. Moreover, the main process parameters of BTF for chlorobenzene degradation were optimized. The results showed that the degradation effect of chlorobenzene reached more than 85% at an inlet concentration of chlorobenzene 700 mg·m−3, oxygen concentration of 10%, and an empty bed retention time (EBRT) of 80 s. The mass transfer kinetic analysis indicated that the process of chlorobenzene degradation in the BTF occurred between the zero-stage reaction and the first-stage reaction. This BTF contributed significantly to the biodegradability of chlorobenzene, overcoming the limitation of gas-to-liquid/solid mass transfer of chlorobenzene. The analysis of the species diversity showed that Thermomonas, Petrimona, Comana, and Ottowia were typical organic-matter-degrading bacteria that degraded chlorobenzene efficiently with xylene present. [ABSTRACT FROM AUTHOR]

With the evolution of the human species, the mandibular third molars have varying degrees of impaction, and the impaction process will cause irreversible damage such as damage to the adjacent teeth. At the same time, there are serious intraoperative and postoperative complications in the extraction of impacted teeth. Whether the mandibular third molar is impacted or not, it may appear in the tooth germ stage. This article showed a case of routine mandibular third molar germ extraction and aims to discuss the analysis of the third molar angulation, retromolar space, crown width, root development, and other factors through the panoramic tomography taken during the tooth germ period and predict the possibility of third molar impaction. At the same time, according to the predicted results, preventive tooth germ extraction or scientific management of tooth germs for the highly likely impacted molars. Compared with fully mature impacted teeth, tooth germ extraction can reduce the difficulty of surgery and reduce trauma. [ABSTRACT FROM AUTHOR]

Background and Purpose: Tooth eruption is a complicated process regulated by the dental follicles (DF). Our recent study discovered that tooth eruption was inhibited upon injection of bleomycin into DF. However, the mechanisms were unknown.Experimental Approach: Human dental follicle cells (hDFCs) were treated by bleomycin or exogenous TGF-β1 or transfected by plasmids loading SMAD7 or shRNA targeting SMAD7, followed by osteogenesis induction assay and signalling analysis. Human fresh DF tissues and Wistar rats were used to further confirm bleomycin function.Key Results: Bleomycin decreased expression of RUNX2 and osteogenic genes in hDFCs, reducing osteogenic capacity. TGF-β1 expression was up-regulated in bleomycin-treated hDFCs. The effects of exogenous TGF-β1 were similar to those of bleomycin in hDFCs. Additionally, compared to SMAD2/3, SMAD7 expression increased more in bleomycin- or TGF-β1-treated hDFCs. Overexpression of SMAD7 likewise significantly decreased RUNX2 expression and osteogenic capacity of hDFCs. Knockdown of SMAD7 markedly attenuated the inhibitory effects of bleomycin and TGF-β1 on osteogenic capacity and RUNX2 expression of hDFCs. Most importantly, changes in TGF-β1, SMAD7, and RUNX2 expressions were similar in the DF of rats and humans treated with bleomycin.Conclusion and Implications: SMAD7 was a negative regulator of osteogenic differentiation in DFCs through suppressing RUNX2 expression. Bleomycin or TGF-β1 inhibited osteogenic differentiation of DFCs via a TGF-β1/SMAD7/RUNX2 pathway. Our findings might be beneficial for enhancing the osteogenic activity of DFCs or inhibiting the eruption of undesirable teeth. [ABSTRACT FROM AUTHOR]

As the main component of silicon (Si)-based Optic Electronics Integrated Circuit (OEIC) chip, Si-based infrared photodetector operating at communication wavebands is very important. In this paper, we report a kind of chromium (Cr)-hyperdoped black Si material fabricated using femtosecond laser pulses irradiation. The concentration of the Cr atoms in the black Si layer exceeds 1020 cm−3 and the Cr-hyperdoped Si has a large sub-bandgap absorptance (~60% for $1.31 \boldsymbol {\mu }\text{m}$). The deep-energy level introduced by Cr impurity is 0.39 eV below the bottom of conduction band and thus the ionized electron concentration is very low (~1015 cm−3). Owing to the excellent sub-bandgap absorption of Cr-hyperdoped Si, face-to-face black Si photodiodes are fabricated. Under illumination of $1.31 \boldsymbol {\mu }\text{m}$ light, the responsivity of the photodiodes based on N+-N junction reaches 0.57 A/W at 4.3 V bias. In addition, the rise and delay time of the device to the infrared light are on the order of milliseconds. [ABSTRACT FROM AUTHOR]