Advanced Materials Research Vols. 383-390

Abstract: The initial alignment error model of SINS (Strap-down Inertial Navigation System) with large misalignment angle is nonlinear. The traditional EKF (Extended Kalman Filter) was used to linearization a nonlinear system, but its performance is limited. In this paper we use the SRUKF (Square Root Unscented Kalman Filter) to process this nonlinear system and the results indicate that SRUKF is better than EKF in convergence speed and estimation accuracy.

Abstract: Transformer is important power transmission equipment, and its working condition directly affects the safety level. Using the Fourier transformer infrared spectrometer for the qualitative analysis of the fault gases, using the theory of BP neural network for the quantitative analysis of the characteristics of the fault gases, can determine the operational status of transformer. This method monitors the function of the transformer effectively, judges the potential failure or hidden dangers accurately.

Abstract: The generation of digital micro-fluid is indispensable operation unit for lab-on-a-piezoelectric-substrate. A new generation method of digital micro-fluid is proposed in this paper. An interdigital transducer (IDT) and a reflector were fabricated on 1280 YX-LiNbO3 substrate, which was used to excited surface acoustic wave. A needle with 400um inside diameter connected with a syringe was on the piezoelectric substrate, of which space could be adjusted. The needle tip and the piezoelectric substrate were coated with Teflon AF 1600. Water was used to generate digital micro-fluid experiments due to most samples or reagents being water solution. Experimental results show that the volumes of generated digital micro-fluid are relied on the space between the needle tip and the piezoelectric substrate, contact angle of the needle tip and RF power acted on the IDT. When the flow velocity of the syringe being 2.269 mm/min, space between the needle tip and the substrate being 0.98mm and 34mdB RF signal power, the volume of the generated water digital micro-fluid is 2ul. Change the space and RF signal power, the volume of generated water digital micro-fluid is also different. The method of generating digital micro-fluid can be greatly useful for Lab-on-a-piezoelelctric-chips.

Abstract: We developed a digital micro-fluid generator for the discrete dispensing of bio-samples into a bio-analytical unit on piezoelectric substrate. This micro-fluid device is comprised of a micro-channel, a step and a 1280 yx-LiNbO3 substrate. An ejector jet pump is used for offering a uniform linear velocity. After formed micro-fluid from micro-channel arrives the step, it will be down to the piezoelectric substrate due to its gravity and will be transported by surface acoustic wave (SAW). The micro-fluid generator can generate mono-disperse digital micro-fluid of micro-liter volume relied on the gap between micro-channel and the step. The generation time of digital micro-fluid is about several seconds time, which is also relation to the gap. And the digital micro-fluid generation is repeatable and stable with a typical variation of less than 7% of digital micro-fluid volume. Our digital micro-fluid generator can be effectively applied to biochemical analysis on a piezoelectric substrate.

Abstract: This paper presents a low bit rate speech coder based on predictive lattice vector quantization (PLVQ) and time-scale modification (TSM). The coding model of proposed vocoder is built on the MELP, in which bit rate reduction is achieved by taking advantage of PLVQ and TSM techniques. PLVQ is used to encode the speech line spectrum pair (LSP) parameters, which has the advantage of lower implementation complexity than multi-stage vector quantization (MSVQ), moreover, it does not require memory for codebook storage. With our speech data base, PLVQ can save up to 4 bits/frame compared to unstructured codebook MSVQ. TSM can change the speed of speech signal with its perceptual characteristics remained. Through appending TSM as previous and post process, speech coding at bit rate about 1.1 kbps could be easily achieved without modifying the vocoder structure.

Abstract: The primary of the research is decrease the traditional touched measurement complexity and modern three-dimensional untouched measurement high cost .The technique applied in the paper is referred to as follow: designing a rotating platform to control the people standing firstly, designing a video collecting system to obtain the body front and side images secondly, acquiring contour extraction through image preprocessing thirdly, obtaining anthropometric characteristics of image according to all parts of the body under the proportional and body three-dimensional contour curve fourthly, obtaining characteristic parameters of the actual body measurement by the camera calibration parameters finally. The results of the research demonstrated that the system is portable, high accuracy, low cost, particularly suitable for large, rapid measurement of body.

Abstract: The performance of excitation control system directly influences the motor’s movement characteristics. Currently, a lot of traditional excitation systems which use analog control circuits have the problem with their poor stability, aging components, slow response and great power lose. Aim to solve these problems, this text designs and implements a digital excitation regulation system based on DSP for DC motor. The regulation system takes full advantage of the powerful data processing ability of DSP chip for real-time rotational speed control of DC motor. This design is capable of ensuring the stability of the excitation system and improving the control efficiency, the circuit design is greatly simplified at the same time.

Abstract: Well site safety plan, which included well design, emergencyresponse plan (ERP) etc, is the key prerequisite for drilling the critical sour gas well. A right emergency response zone (EPZ) is quite difficult to make sure on the site, because that it affected by release rate of H2S, gas composition, the well site surrounding topography, and other specific circumstances. To solve this problem, A blowout simulation software based on FLUENT be developed, which could predict affected areas when the critical sour blowout, the gas flow direction, and the H2S concentration distribution. On this basis, the safety layout surrounding the well site can be planned. The article provides the design structure and main functions of the software. The software can provide the theoretical basis of industrial safety.

Abstract: Based on the quality factors of the precision injection product, the control system structure of precision injection molding product and proposes the on-line measurement of melt density which controls the injection weight is analyzed in this thesis. The important of the on-line measurement of melt density is shown in this paper. Then, the approach of off-line and on-line measurement of melt density is introduced. At last, the control approach and the precision injection control principle of using the on-line measurement of melt density is discussed also.

Abstract: With the PV power system capacity continues to expand, PV power generation forecasting techniques can reduce the PV system output power of randomness, it has great impact on power systems. This paper presents a method based on ARMA time series power prediction model. With historical electricity data and meteorological factors, the model gets test and evaluation by Eviews software. Results indicated that the prediction model has high accuracy, it can solve the shortcomings of PV randomness and also can improve the ability of the stable operation of the system.