Adaptive Streaming in Mobile Network

Mobile ecommerce is immersed rapid familiar to other high-flying Internet markets. With the fast developing of wireless connections and Internet, electronic commerce more and more moves to mobile environment. Streaming, as a rapid growing application in Internet, will be more used in mobile ecommerce. In this paper, we’ll review the network protocol used in mobile ecommerce and streaming technology. An optimized architecture is given based on MPEG-4 and Mobile Ipv6. The core streaming protocol used in this architecture is RTSP/RTP proposed by IETF. This system gives one possible implementation of streaming over wireless network. Two key bottlenecks we found in this project are wireless bandwidth and mobile client power. To avoid the two problems, self-adaptive methodology is used. Let streaming application be adaptive to the wireless network environment to improve streaming performance

Multi-body dynamic simulation and vibration transmission characteristics of dual-rotor system for aeroengine with rubbing coupling faults

In this paper, a dual-rotor system multi-body dynamic model with rubbing coupling faults is established for practical aero-engine. In the model, the rubbing fault simulation method is introduced, the coupling effect between the internal and external rotor is considered. The numerical simulations of rotor vibration are accomplished by the utilization of multi-body dynamic platform, where the simulation model consists of discs unbalances and local rub-impact between discs and casing shells. The time-domain responses, the frequency spectra and the shaft-center trajectories of dual-rotor with different unbalance and different rubbing positions are obtained. The vibration and its transmission characteristics of the inner and outer rotors are calculated. Finally, the simulation results are compared with the measured vibration of a dual rotor tester with rubbing fault. The simulation results are consistent with the measured results, which confirms the feasibility of the established model and the multi-body dynamics simulation method in this paper. The application of multi-body dynamics simulation method in aero-engine can deepen the understanding of the internal operation nature and laws of aero-engine, reduce the repetition of physical tests, greatly improve the efficiency and quality of development, accelerate the research and manufacture process

Equivalent Modeling of DFIG-Based Wind Power Plant Considering Crowbar Protection

Crowbar conduction has an impact on the transient characteristics of a doubly fed induction generator (DFIG) in the short-circuit fault condition. But crowbar protection is seldom considered in the aggregation method for equivalent modeling of DFIG-based wind power plants (WPPs). In this paper, the relationship between the growth of postfault rotor current and the amplitude of the terminal voltage dip is studied by analyzing the rotor current characteristics of a DFIG during the fault process. Then, a terminal voltage dip criterion which can identify crowbar conduction is proposed. Considering the different grid connection structures for single DFIG and WPP, the criterion is revised and the crowbar conduction is judged depending on the revised criterion. Furthermore, an aggregation model of the WPP is established based on the division principle of crowbar conduction. Finally, the proposed equivalent WPP is simulated on a DIgSILENT PowerFactory platform and the results are compared with those of the traditional equivalent WPPs and the detailed WPP. The simulation results show the effectiveness of the method for equivalent modeling of DFIG-based WPP when crowbar protection is also taken into account.</jats:p

Research Progress on the Relationship between Polymorphism and SLE of Vitamin D Metabolic Pathway Related Gene

Vitamin D is a class of hormones necessary to maintain normalphysiological activities of the body. A large number of studies have shownthat vitamin D, as a fat-soluble vitamin, is not only related to calcium andphosphorus metabolism, but also closely related to immune regulation,humoral regulation, cell cycle and so on. Systemic Lupus erythema-Tosus(SLE) is a specific autoimmune diffuse connective tissue disease thatcauses tissue and organ damage under the joint action of multiple factorssuch as environment and heredity. Among many factors, the vitamin Dmetabolism pathway gene is particularly important for its influence. Someliterature has shown that the genetic polymorphism of vitamin D metabolicpathway genes is correlated with SLE. Therefore, by referring to relevantliterature, this paper summarized the progress in the research on themechanism of genetic polymorphism of vitamin metabolism pathway genesand the development of SLE

Sodium quercetin-8-sulfonate trihydrate

The organic anion of the title compound, {[Na(C15H9O10S)(H2O)2]·H2O}n {systematic name: poly[[diaqua­[μ-2-(3,4-dihy­droxy­phen­yl)-3,5,7-trihy­droxy-4-oxo-4H-chromene-8-sulfon­ato]­sodium] monohydrate]}, has a nearly planar structure. The Na atom is six-coordinated by O atoms, two from water mol­ecules and four from the anion. The dihedral angle between the ring systems in the anion is 10.1 (1)°. Intra­molecular O—H⋯S and O—H⋯O inter­actions occur. In the crystal structure, an extensive network of classical inter­molecular O—H⋯S and O—H⋯O hydrogen bonds forms layers along the c axis

A Topology Structure Based Outer Membrane Proteins Segment Alignment Method

Outer membrane proteins (OMPs) are transmembrane proteins (TMPs) located in outer membranes. These proteins perform diverse biochemical functions and have immediate medical relevance, so that their spatial structures are important for studying. But the special physicochemical properties of OMP make it hard to obtain their structures experimentally. For the purpose of predicting OMP structures, discriminating OMPs and aligning their sequences to native structures are indispensable steps. We developed a novel method OMSA (Outer Membrane Segment Alignment), which implemented both steps in one program. OMSA integrates OMP-specific topology features to implement a sequence-to-structure alignment, for example, segment type and segment orientation, while a segment-dependent gap penalty model is employed to improve the alignment. Compared to peer top-leading methods, OMSA achieved higher accuracy in both OMP discrimination and alignment, which may further improve OMP structure studying.</jats:p

Constructing quantum dots@flake g-C3N4 isotype heterojunctions for enhanced visible-light-driven NADH regeneration and enzymatic hydrogenation

The authors thank the financial support from National Natural Science Funds of China (21406163, 91534126, 21621004), Tianjin Research Program of Application Foundation and Advanced Technology (15JCQNJC10000), Open Funding Project of the National Key Laboratory of Biochemical Engineering (2015KF-03), and the Program of Introducing Talents of Discipline to Universities (B06006). X.W. also acknowledges financial support from The Carnegie Trust for the Universities of Scotland (70265) and The Royal Society (RG150001 and IE150611).Peer reviewedPostprin