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With the large-scale grid connection of new energy power, the random fluctuation existing in the power system is intensified, which leads to frequent fluctuation of load instructions of thermal power units. It is of great significance to improve the variable load performance of the coal-fired units. It is more difficult to control the superheated steam temperature (SST). In order to improve the control performance of SST, a state variable fuzzy predictive control method is proposed in this paper. Firstly, Takagi-Sugeno fuzzy state observer is used to approximate the non-linear plant of the SST. At the same time, based on the state observer, a fuzzy state feedback controller is designed to improve its dynamic characteristics. Thirdly, based on the extended predictive model of the state feedback controller, a model predictive controller is designed to realize the SST tracking control. Dynamic simulation shows the effectiveness of the strategy. [ABSTRACT FROM AUTHOR]

The authors present a novel wideband two‐dimensional voltage‐controlled attenuator (VCA). The proposed design employs both stacked‐FET configuration and distributed structure to achieve wideband performance, high power, and high dynamic range simultaneously. A systematic design methodology is also illustrated along with a fabricated prototype to verify the concept. The chip fabricated in a 0.15‐μm Gallium Arsenide (GaAs) process exhibiting a measured power at 1‐dB compression (P1dB) of 25.5 dBm with a corresponding dynamic range of 32 dB. The insertion loss ranges from 2 to 5 dB over the bandwidth from 2 to 40 GHz. Furthermore, the chip is not only very compact (0.84 mm2), but it also requires only a single positive supply voltage, which makes it more appealing to highly integrated wireless applications. [ABSTRACT FROM AUTHOR]

The synthesis and crystal structure of peptide 6,60-dimethyl biphenyl hybrid are described. The title compound was synthesized by reaction between 6,60- dimethyl-[1,1'-biphenyl]-2,2'-dicarbonyl dichloride in CH2Cl2, amine HN-- proline--phenylalanine--alanine--COOMe and Et3N at 273 K under N2 atmosphere and characterized by single-crystal X-ray diffraction. The asymmetric unit contains one peptide molecule and a quarter of a water molecule. A disorder of a methyl and methoxycarbonyl group of one alanine residue is observed with occupancy ratio 0.502 (6):0.498 (6). The structure is consolidated by intra- and intermolecular hydrogen bonds. [ABSTRACT FROM AUTHOR]

A peptide biphenyl hybrid compound {systematic name: dimethyl 2,2'-[((2S,2'S)-2,2'-{[(2S,2'S)-1,1'-([1,1'-biphen­yl]-2,2'-dicarbon­yl)bis­(pyrrolidine-1,2-diyl-2-carbon­yl)]bis­(aza­nedi­yl)}bis­(3-phenyl­propano­yl))bis­(aza­nedi­yl)](2S,2'S)-dipropionate hemihydrate}, C50H56N6O10·0.5H2O, was prepared by coupling of [1,1'-biphen­yl]-2,2'-dicarbonyl dichloride, tri­ethyl­amine and the tripeptide Pro-Phe-Ala in CH2Cl2 at 273K under an N2 atmosphere. In the crystal, the asymmetric unit contains the peptide biphenyl hybrid accompanied by one-half of a water mol­ecule. A C atom of one of the proline rings is disordered between two positions in a 0.746(11):0.254(11) ratio. An important structural aspect of peptide compounds is their capacity to self-associate mediated by inter­molecular and intra­molecular hydrogen bonding. This characteristic can be useful in understanding the inter­actions between peptides and biomacromolecular targets, as well as to explain peptide properties. [ABSTRACT FROM AUTHOR]

This paper presents a proposal and implementation of a multi-mode full-reconfigurable router for Network-on-Chip (NoC). First, the router supports a hybrid packet-switching architecture that is dynamically reconfigurable to exchange between wormhole and virtual cut-through switching schemes at run-time. Therefore, it reaches a higher average performance than wormhole switching, while decreasing the implementation cost in comparison with the virtual cut-through switching. Second, the router is equipped a Quality-of-Services (QoS)-driven arbiter. Therefore, the proposed solution not only guarantees the guaranteed-throughput service without reserving resources but also enhances the average performance for the best-effort service by using network resources efficiently based on the priority inheritance arbitration mechanism. Third, the router is enhanced with the dynamically deadline-aware rerouting mechanism. In contention situation, the router can configure the routing computation unit to reroute the packet to another path so as to reduce the waiting interval of the blocked packets. The router was designed at the Register Transfer Level and modeled using VHDL language and then synthesized with Xilinx Virtex-7 FPGA technology. The experimental results prove that the proposed router is reliable and can improve the average performance of different QoS loads significantly compared with the generic routers while the area and power overhead are acceptable. [ABSTRACT FROM AUTHOR]

Recently, radio frequency (RF) energy harvesting (RFEH) has become a promising technology for a battery-less sensor module. The ambient RF radiation from the available sources is captured by receiver antennas and converted to electrical energy, which is used to supply smart sensor modules. In this paper, an enhanced method to improve the efficiency of the RFEH system using strongly coupled electromagnetic resonance technology was proposed. A relay resonator was added between the reader and tag antennas to improve the wireless power transmission efficiency to the sensor module. The design of the relay resonator was based on the resonant technique and near-field magnetic coupling concept to improve the communication distance and the power supply for a sensor module. It was designed such that the self-resonant frequencies of the reader antenna, tag antenna, and the relay resonator are synchronous at the HF frequency (13.56MHz). The proposed method was analyzed using Thevenin equivalent circuit, simulated and experimental validated to evaluate its performance. The experimental results showed that the proposed harvesting method is able to generate a great higher power up to 10 times than that provided by conventional harvesting methods without a relay resonator. Moreover, as an empirical feasibility test of the proposed RF energy harvesting device, a smart sensor module which is placed inside a meat box was developed. It was utilized to collect vital data, including temperature, relative humidity and gas concentration, to monitor the freshness of meat. Overall, by exploiting relay resonator, the proposed smart sensor tag could continuously monitor meat freshness without any batteries at the innovative maximum distance of approximately 50 cm. [ABSTRACT FROM AUTHOR]

Seeking a strategy for triggering the cryptic natural product biosynthesis to yield novel compounds in the plant-associated fungus Xylaria sp., the effect of culture conditions on metabolite production was investigated. A shift in the production of five known cytochalasin-type analogues 1-5 to six new α-pyrone derivatives, xylapyrones A-F (compounds 6-11), from a solid to a liquid medium was observed. These compounds were identified by analysis of 1D and 2D NMR and HRMS data. Compounds 1-3 showed moderate cytotoxicity against HepG2 and Caski cancer cell lines with IC50 values ranging from 25 to 63 μM and compounds 4-11 were found to be inactive, with ICY50 values >100 μM. [ABSTRACT FROM AUTHOR]