A QoS-Aware Scheduling Algorithm for High-Speed Railway Communication System

With the rapid development of high-speed railway (HSR), how to provide the passengers with multimedia services has attracted increasing attention. A key issue is to develop an effective scheduling algorithm for multiple services with different quality of service (QoS) requirements. In this paper, we investigate the downlink service scheduling problem in HSR network taking account of end-to-end deadline constraints and successfully packet delivery ratio requirements. Firstly, by exploiting the deterministic high-speed train trajectory, we present a time-distance mapping in order to obtain the highly dynamic link capacity effectively. Next, a novel service model is developed for deadline constrained services with delivery ratio requirements, which enables us to turn the delivery ratio requirement into a single queue stability problem. Based on the Lyapunov drift, the optimal scheduling problem is formulated and the corresponding scheduling service algorithm is proposed by stochastic network optimization approach. Simulation results show that the proposed algorithm outperforms the conventional schemes in terms of QoS requirements.Comment: 6 pages, 3 figures, accepted by IEEE ICC 2014 conferenc

Clinical treatment on patients with infectious keratitis by chestnut thorn

AIM:To investigate the clinical treatment on patients with infectious keratitis by chestnut thorn. <p>METHODS: Retrospective analysis of 28 cases(28 eyes)with infectious keratitis due to chestnut thorn from June 2009 to October 2012. All patients had the clinical manifestations such as local infiltration, edema and ulcer formation. Chestnut thorn located deeply into corneal stroma, but did not penetrate into the anterior chamber. All patients underwent emergency surgery to remove chestnut thorn, of which 14 patients underwent corneal debridement joint multilayer amniotic membrane transplantation as the treatment group, and the other 14 patients refused amniotic membrane transplantation and had the chestnut thorn removed only as the control group. The corneal epithelial healing time, the degree of improvement of visual acuity and the incidence of complications were compared between the two groups after 3 months.<p>RESULTS: The corneal epithelial average healing time of the treatment group was significantly shortened compared with the control group(<i>t</i>=13.6, <i>P</i><0.05), the visual acuity of the treatment group was improved significantly higher than that in the control group, and the incidence of complications of the treatment group was significantly decreased compared with the control group. <p>CONCLUSION: For the patients with corneal ulcer due to deep chestnut thorn, emergency surgery of corneal debridement joint multilayer amniotic membrane transplantation can promote the repair of the cornea and prevent the occurrence of complications after injury

(S)-2-[(S,Z)-3-Bromo-1-nitro-4-phenyl­but-3-en-2-yl]cyclo­hexa­none

In the crystal structure of the title compound, C16H18BrNO3, the two stereogenic centres both have an S configuration. The cyclo­hexyl ring adopts a chair conformation. In the crystal, mol­ecules are linked by weak N—O⋯Br contacts [O⋯Br = 3.289 (4) Å]

Diversity of archaea and bacteria in a biogas reactor fed with Pennisetum sinese Roxb by 16S rRNA sequence analysis

Purpose: To investigate the structure and function of the complex rumen microbial community in a biogas reactor by 16S rRNA gene analysis, which was fed with Pennisetum sinese Roxb as the monosubstrate.Methods: Two 16S ribosomal RNA (rRNA) clone libraries of bacteria and archaea were established by polymerase chain reaction. Community structure was determined by phylogenetic analyses of 119 and 100 16S rRNA gene clones from the bacterial and archaeal libraries, respectively.Results: In the bacterial library, 13.4 % of clones were affiliated with Treponema porcinum, 5.9 % with Eubacterium limosum, 5 % with Clostridium, 5 % with Bacteroidetes, 4.2 % with Firmicutes, 2.5 % with Anaerofilum and a total of 64 % clones belonged to unclassified or uncultured bacteria. In the archaeal library, Methanobacterium curvum made up 12 % of known clones, Methanosarcina barkeri represented 8 %, Methanobacterium bryantii represented 4 % and Methanofollis ethanolicus represented 2 %, respectively; the remaining 74 % of the clones were unclassified archaebacteria.Conclusion: T. porcinum and M. curvum are the most predominant bacteria and archaea in a biogas reactor fed with P. sinese as the sole substrate.Keywords: Pennisetum sinese Roxb, Archaea, Bacteria, Biogas reactor, 16S rDNA sequencin

3-Ethyl-1H-1,2,4-triazole-5(4H)-thione

The mol­ecule of the title compound, C4H7N3S, exists as the thione tautomer in the solid state. The asymmetric unit consits of one mol­ecule in which all atoms are located on a crystallographic mirror plane. In the crystal, adjacent mol­ecules are linked by N—H⋯N and N—H⋯S hydrogen bonds into chains running along the a axis. π–π stacking inter­actions between the triazole rings [centroid–centroid distance = 3.740 (1) Å and inter­planar distance = 3.376 Å] may further stabilize the structure

Combined analysis of the γn→K0Σ0\gamma n \to K^0\Sigma^0 and γn→K+Σ−\gamma n \to K^+\Sigma^- reactions

The recently released data on differential cross sections for $\gamma n \to K^0\Sigma^0$ from the A2 and BGOOD Collaborations are used to examine the theoretical model constructed in our previous work [Phys. Rev. D \textbf{105}, 094017 (2022)] for $\gamma n \to K^+\Sigma^-$, and it is found that the model predictions are able to qualitatively reproduce the A2 data but fail to describe the BGOOD data. Then, a combined analysis of the $\gamma n \to K^0\Sigma^0$ and $\gamma n \to K^+\Sigma^-$ reactions is performed to revise the theoretical model. Due to the inconsistency problem, the A2 and BGOOD data are included in fits separately. In the case of including the A2 data, both the data for $\gamma n \to K^0\Sigma^0$ and $\gamma n \to K^+\Sigma^-$ can be fairly well described, and the contributions from the $N(1710)1/2^+$, $N(1880)1/2^+$, $N(1900)3/2^+$, and $\Delta(1920)3/2^+$ resonances are found to dominate the reactions in the lower energy region. While in the case of including the BGOOD data, although most of the data for the $\gamma n \to K^+ \Sigma^-$ reaction can be described with the exception of some noticeable discrepancies on beam asymmetries at lower energies, the BGOOD data for $\gamma n \to K^0\Sigma^0$ can be only qualitatively described, and the contributions from the $N(1710)1/2^+$, $N(1900)3/2^+$, and $\Delta(1910)1/2^+$ resonances are found to dominate the reactions in the lower energy region. In both cases, the $t$-channel $K^\ast(892)$ exchange is found to play a crucial role at forward angles in the higher energy region. Further precise measurements of data for $\gamma n \to K^0\Sigma^0$ are called on to disentangle the discrepancies between the data sets from the A2 and BGOOD Collaborations.Comment: 14 pages,17 figures; Accepted for publication in Physical Review