Abstract: A method for state estimation of a distribution network comprises: (a) obtaining measurements from phasor measurement units (PMUs) placed at buses in the distribution network; (b) constructing a quotient gradient system (QGS) based on a constraint set H that relates the measurements to state variables of the distribution network; (c) integrating the QGS to reach a steady state; (d) identifying one or more of the state variables whose measurement residuals violate a measurement residual constraint in the constraint set H; (e) integrating a reconstructed QGS, which is reconstructed based on the constraint set H by setting the identified one or more state variables to values of corresponding PMU measurements; (f) iterating steps of (d) and (e) until no measurement residuals violate the measurement residual constraint, to thereby obtain the state estimation; and (g) reporting the state estimation to a control system during real-time monitoring of the distribution network.

Abstract: A method for preparing biochar and hydrogen by utilizing anaerobic fermentation byproducts, the method including: (1) mixing a first straw, seeding sludge and distilled water, and then carrying out anaerobic fermentation to obtain a mixed product after fermentation; (2) performing separation on the mixed product to obtain a second straw and biogas slurry; and (3) carbonizing the second straw to obtain biochar, and collecting gas after a pressurized catalytic reaction on the biogas slurry to obtain hydrogen.

Abstract: The present invention provides an asymmetric EEG-based coding and decoding methods for BCIs, the BCI system includes an evoked stimulus module, an acquisition module and an EEG signal data set including a training set Xk and a testing sample Y, and an EEG signal decoding module; the evoked stimulus module sends a hybrid coding visual stimulus to subjects to evoke a specific EEG signal as required; the acquisition module obtains data information by amplifying and filtering the EEG signal so as to constitute EEG signal module; the decoding module coverts the data information into an instruction set for outputting the coding method of the present invention uses asymmetric characteristics of brain electrophysiological activity response to stimulus, combines with coding strategies such as SDMA, CDMA, FDMA and phase division multiple access coding.

Abstract: The present invention related to the field of power system protection and control, presents a voltage travelling wave differential protection method considering the influence of frequency-dependent parameters, which provides more accurate and rapid fault identification. The technical scheme of the present invention is as follows: a calculation method of voltage travelling-wave differential protection for VSC-HVDC transmission lines, taking the influence of the frequency-dependent parameters into consideration, the steps are as follows: calculating a characteristic impedance and propagation coefficient of the frequency-dependent transmission line in time domain, collecting voltage and current signals at the both ends of the transmission line and then calculating the forward and backward voltage travelling wave, respectively, comparing a differential value of voltage travelling wave with a preset threshold value to determine whether the internal fault occurs.

Abstract: Disclosed is a method for calculating combustion in the bed of a waste incinerator. The method is based on a model of combustion in a waste incinerator bed and comprises a water evaporation model, a volatile matter analysis model, a volatile matter combustion model, and a fixed carbon combustion model. The volatile matter of the volatile matter combustion model comprises CO, H2, CH4, NH3, and H2S. The volatile matter combustion model comprises a combustion reaction equation for said volatile matter and O2, and respective equations for CO and CH4 reacting with water vapor. Equations governing the model of combustion in the bed of a waste incinerator comprise a continuity equation, an energy equation, a momentum equation, and a component equation. Boundary conditions of said governing equations comprise: equations of heat transfer and mass transfer from an upper boundary layer of the bed to the exterior; and equations of heat transfer and mass transfer from lower boundary layer of the bed to the exterior.

Abstract: The present invention discloses a Fiber Bragg Grating demodulation device with a suppressed fluctuation at a variable ambient temperature and a demodulation method. The device comprises a broadband light source (1), an optical attenuator (2), a tunable F-P filter (3), a first optical fiber isolator (41), an erbium-doped optical fiber amplifier (5), an optical fiber first-stage beam splitter (6), a first optical fiber second-stage beam splitter (71), optical fiber circulators (8), FBG sensor arrays (9), a first photoelectric detector array (161), an optical fiber gas cell (10), a second optical fiber second-stage beam splitter (72), an optical fiber F-P etalon (11), a notch filter (12), an optical fiber assisted interferometer (13), a data acquisition card (17) and a processor (18).

Abstract: The present disclosure provides recombinant Pichia pastoris, a construction method thereof, and use thereof in the efficient preparation of 15?-D-ethylgonendione, and belongs to the technical field of fermentation engineering. In the present disclosure, with Pichia pastoris as a host, 15?-steroid hydroxylase and glucose-6-phosphate dehydrogenase (G6PD) are simultaneously induced in a manner of intracellular enzyme production for the first time, and the Pichia pastoris whole-cell induction and catalysis mode is used to achieve the conversion of D-ethylgonendione with high substrate loading and high conversion rate.

Abstract: Provided is a method for preparing a carbon nanotube/polymer composite material, including: coating a nano-silicon oxide film on the surface of a porous polymer by vacuum coating; depositing a metal catalyst nano-film on the nano-silicon oxide film by vacuum sputtering; growing a carbon nanotube array in situ on the surface of the porous polymer by plasma enhanced chemical vapor deposition to obtain a carbon nanotube/polymer porous material; and impregnating the carbon nanotube/polymer porous material with a polymer and curing to obtain the carbon nanotube/polymer composite material. By using a heat-resistant polymer having a high heat-resistant temperature and a PECVD technique, a carbon nanotube array directly grows in situ on the surface of a polymer at a low temperature, which thereby overcomes the defects of the composites previously prepared, in which carbon nanotubes are difficult to be homogeneously dispersed and the interfacial bonding force in the composites is weak.

Abstract: An optical waveguide structure has a waveguide core including an inner and an outer layer with different refractive indices, and a refractive index ratio of the different refractive indices is greater than or equal to 1.15. A dispersion controlling method using the optical waveguide structure includes: first, obtaining a dispersion curve having up to 5 zero-dispersion wavelengths by calculating based on a set of preset structural size parameters of the optical waveguide; and then, adjusting one or more of the width (W) of a contact surface between the inner layer and the substrate, the thickness (H) of a higher refractive index material, and the thickness (C) of a lower refractive index material, so as to implement dispersion control.

Abstract: The present invention discloses a control method of variable stroke engine for reforming high-octane fuel under the FCE mode, the ECU connected to the engine controls the amount of fuel injected from the flexible cylinder injector to the flexible cylinder and controls the switch state of inlet valve and exhaust valve of the flexible cylinder, so that the flexible cylinder can be switched between two-stroke mode and four-stroke mode according to the actual engine operating conditions; when the engine is at a small load and needs to promote combustion stability, the flexible cylinder injector injects a rich fuel with equivalence ratio greater than 1 into the flexible cylinder, the flexible cylinder is at two-stroke mode; when the engine is at a large load and needs sufficient power output, the flexible cylinder injector injects a conventional fuel into the flexible cylinder, said flexible cylinder is at four-stroke mode.

Abstract: The present invention discloses a method for detecting the mechanical response of a mechanical component by an organic mechanoresponsive fluorescent material, comprising the following steps of: selecting an organic mechanoresponsive fluorescent material; preparing an organic mechanoresponsive fluorescent material solution; forming a film on a metal surface; calibrating fluorescence intensity and obtaining the fluorescence intensity and distribution in a crack tip area; observing the fluorescence signal generated at cracks to monitor the occurrence of fatigue cracks, and predict a propagation pathway of fatigue cracks by using the fluorescence intensity distribution in the crack tip area.

Abstract: The present invention a mixed fuel suitable for diesel engines, which consists of the following components by volume percentage: 35% to 37.5% of diesel, 35% to 37.5% of ethanol and 25% to 30% of PODE, wherein the diesel is petroleum diesel having a cetane number not less than 48; the purity of the ethanol by mass percentage is not less than 99.5%; and, the PODE is a mixture of two fuels shown by molecular formulae CH3O(CH2O)3CH3 and CH3O(CH2O)4CH3. The use of this fuel is advantageous for emission reduction.

Abstract: The present disclosure provides a polymer solid electrolyte comprising a high molecular polymer and a lithiated carbon dot, wherein the lithiated carbon dot is obtained by lithiating a carbon dot with lithium hydroxide. The present application also provides a method for preparing a lithiated carbon dot and a method for preparing a polymer solid electrolyte. In the polymer solid electrolyte provided in the present application, the lithiated carbon dot is used as lithium salts, and the introduction of the lithiated carbon dot effectively reduces the crystal phase of the polymer matrix in the electrolyte, and significantly improves the electrochemical properties such as the ionic conductivity and ionic mobility of the polymer solid electrolyte.

Abstract: The present disclosure relates to the field of the catalytic technologies, and provides a p-type TiO2/n-type WO3 heterojunction catalyst and its preparation and use in photochemical synthesis of fuels. The catalyst comprises p-type TiO2 and n-type WO3 supported on a surface of the p-type TiO2. The disclosure proposes to support n-type WO3 onto a surface of p-type TiO2. The catalyst has high catalytic efficiency, and is particularly suitable for use in photocatalytic processes for synthesizing fuels.

Abstract: The present invention discloses an electromagnetic braking system and control method, the system comprises a CCU, a braking cylinder, a push rod, an electromagnetic braking ring, an electromagnetic braking piston fixed to the push rod, a first shading plate and a second shading plate, a photoelectric sensor fixed near the push rod, and an electromagnetic braking control circuit. The control method includes following steps: initial estimating the braking distance l according to the current magnitude, electromagnetic force between the two electromagnetic coils and initial velocity v of the push rod, arranging a restoration distance ?l between the top dead center and the piston after braking, installing two shading plates and the photoelectric sensor; setting the distance between the two electromagnetic coils to L=l+?l when starting the braking.

Abstract: The present application discloses a supported PtZn intermetallic alloy catalyst, a method for preparing the same and application thereof. The catalyst uses SiO2 as a support and Zn as a promoter, and a small amount of active component Pt is supported; the weight percentage of Pt is 0.025%-1%, and the weight percentage of Zn is 0.025%-1.7%, a co-impregnation method is adopted in preparation, the SiO2 support is impregnated in aqueous solution of chloroplatinic acid and zinc nitrate, and then drying and high-temperature reduction are performed to obtain a PtZn/SiO2 catalyst. The catalyst has the advantages of high activity, high stability, low price and low toxicity. The catalyst provided by the present application is applicable to preparation of alkene through short-chain alkane dehydrogenation, in particular to preparation of propylene through propane dehydrogenation in a hydrogen atmosphere.

Abstract: An efficient engine combustion system with multiple combustion modes, includes a valve actuating mechanism, a pre-combustion chamber, and a main combustion chamber. The valve actuating mechanism is a fully variable valve mechanism; an intake valve and an exhaust valve are driven by high-pressure oil; ignition is implemented by means of an ignition apparatus of the pre-combustion chamber; and a spark plug and a single-hole fuel injector are mounted in the pre-combustion chamber, a bottom end of which is provided with a flame jet hole. The continuous variable of valve timing and real-time adjustment of valve lift are realized by the control of a three-position four-way servo valve, driven by the high-pressure oil and monitored by a displacement sensor. The efficient engine combustion system with multiple combustion modes employs different combustion modes under different engine conditions, so as to ensure optimal thermal efficiency under different operating condition regions.

Abstract: The present disclosure relates to a genetically engineered strain with high production of uridine and its construction method and application. The strain was constructed as follows: heterologously expressing pyrimidine nucleoside operon sequence pyrBCAKDFE (SEQ ID NO:1) on the genome of E coli prompted by strong promoter Ptrc to reconstruct the pathway of uridine synthesis; overexpressing the autologous prsA gene coding PRPP synthase by integration of another copy of prsA gene promoted by strong promoter Ptrc on the genome; deficiency of uridine kinase, uridine phosphorylase, ribonucleoside hydrolase, homoserine dehydrogenase I and ornithine carbamoyltransferase. When the bacteria was used for producing uridine, 40-67 g/L uridine could be obtained in a 5 L fermentor after fermentation for 40-70 h using the technical scheme provided by the disclosure with the maximum productivity of 0.15-0.25 g uridine/g glucose and 1.

Abstract: The present invention discloses a DC solid-state circuit breaker with self-adapt fault current limiting capability. The topology of the DC solid-state circuit breaker is a H-bridge circuit consisting of two unidirectional breakable bridge arms and two series-connected diode bridge arms, wherein the two unidirectional breakable bridge arms are connected in series to the two series-connected diode bridge arms in a same direction to form two series branches, respectively; the series branches are connected in parallel; a series branch formed by a DC reactor L and a DC biased power supply is connected to the PCC between the two unidirectional breakable bridge arms and the PCC between the two series-connected diode bridge arms; the DC line is connected to the two PCCs, respectively.

Abstract: Method of constructing a vault of a large storage tank for liquefied natural gas by first modeling the vault with a 3-D modeling software application, then partially building the vault with a framework and a first set of covering panels fixed on the framework where the panels do not touch each other, but leave a number of gaps between them, measuring the dimensions of the actual gaps between the panels using a 3-D scanner, producing a second set of panels according to the scanned dimensional data, and finally filled the gaps between the first set of panels with the second set of panels, which are much smaller than the first set of panels, making the building process earlier and more accurate, which are difficult issues in building large tanks for liquefied natural gas.