Advanced Materials Research Vol. 748

Abstract: In view of the singleness of effect evaluation indexes in combination forecasting, this paper considered both benefit factors and cost factors. The entropy method and the variance-covariance method are adopted to determine the relative importance of these indicators and to get the weight of each single model. This improved combination forecasting model took both prediction accuracy and curve similarity into consideration, which is more accurate and reliable.

Abstract: This paper investigates a high power dual-active isolated DC-DC converter employing LC series resonant technology. The switches of the circuit may work in either zero-voltage-switching (ZVS) or zero-current-switching (ZCS) which greatly reduces the switching power losses and raises the transmission efficiency. The dynamic performance of the circuit and the formula of the output power which no paper has given the exact expression can get by building the DC model of the converter. Finally, simulation and experiment have been conducted to verify the correctness of the analysis.

Abstract: Nowadays, the most of the load is inductive load in the factory. However, power factor is reduced by the phase difference of voltage waveform and current waveform which made by inductor. So many company adopt the compensation mode of parallel capacitor. However, randomly switch for capacitor group make the great harm to power supply system. In order to solve this problem, this paper designs a kind of intelligent synchronous switch. This switch can be switched in the alternating current zero. This switch takes PIC16F877A as core, using of magnetic keeping relay as the executing agency. The experimental results show that the design of this system is reasonable and can make more contribute to enhance the transmission electric efficiency of electrical factory.

Abstract: f the ratio of NPC/H and H bridge hybrid multilevel converters DC supply voltage changed, the output voltage PWM waveform will be discontinuous. Thus an improved topology and control strategy is proposed. In new method, master converter operates at the fundamental frequency based on command voltage, slave converter adopts carrier phase shifted PWM technology (CPS-SPWM) at a higher frequency to enhance the quality of output voltage waveform. The amplitude of command voltage is higher than output voltage amplitude of the master converter at any time, to ensure that output voltage variation of both converters keeps in the same direction without any current flow backwards. Matlab simulation results demonstrate the effectiveness of the proposed control strategy and topology.

Abstract: According to the air flow measurement principle, an automobile conditioner each outlet and atmospheric pressure based on zero characteristics has been developed. The experiment platform adopts V cone flowmeter gas flow indirect measurement of automotive air conditioning of the air outlet pipe, a detailed description of the design of the test bench of mechanical structure, measuring circuit, computer software, through the experimental result analysis, can realize the accurate measurement of air.

Abstract: This system brings forward the CCD measurement method based on oblique laser triangulation , which to resolve the minimal thickness measurement precision problem, in this system use linear array CCD, then used CCD as a photoelectric conversion device, the image on the CCD image point displacement variation to realize planar sheet thickness measurement, design and construction of the contactless thickness measurement system. Finally, the experimental analyze the measurement error of the system, prove the feasibility and validity of the system.

Abstract: Mono pulse algorithm for confocal microwave imaging (CMI) for breast cancer detection is presented in this paper. All the antennas are used as receiver but only one is also used as transmitter. The transmitted signal is emitted for only once, thus the gross electromagnetic wave energy to the breast is reduced and the diagnosis time can be saved. Two confocal microwave imaging algorithms are presented in this paper: delay-sum-max and delay-production-sum. Both algorithms use the same delayed backscattered signals as the convectional CMI. The difference is how to use the delayed signals to form the image of the scattering intensity. Delay-sum-max method adds the signal together to generate the different value in confocal point via coherent and incoherent addition. Delay-production-sum algorithm products the delayed signal so as to make the assigned value in the confocal point outside the tumor is nearly zero. The image results can be compliment for more confirm diagnosis. Finite-difference time-domain (FDTD) method is used for simulation on 3 models of different tumor arrangements. The results show both methods are effective in detecting single-tumor, while there are some limitations in dealing with multi-tumor.

Abstract: In this paper we present some theoretical and practical considerations concerning the development procedures of some correlative investigation techniques (CIT) applied to human performances analysis expressed in specific evolution conditions of some postural malfunctions. These integrated correlative techniques may define and control by feed-back reactions the behavior of some bio-systems or even of some automated and robotized systems.

Abstract: Assisted analyze of the Extenics dependent functions theory is necessary to study easily all influences of the current point in to the space of nR dimensions. The Extenics theory was defined by prof. Cai Wen in 1983 and his collaborators in the mathematical, philosophy and logical models [1-. This paper inspired from the Extenics theory try to transfer the mathematical formalism in to the virtual LabVIEW instrumentation what can be easily establish, by on-line calculus of the dependent functions, the affiliation of one class or interval in the nR dimensions and validate all Extenics conditions. The research established the complex field of the dependent functions, when the work point is inside, outside, symmetrical or asymmetrical position versus the optimal area. In the Extenics theory wasnt defined in this new form the nR dimensions. It is defined also in this paper the attraction field instead of the attraction point defined in [. The paper show the study case of the 2D and 3D dependent on-line functions with define finally the attraction field like the optimized place of the working point.

Abstract: This paper presents the original development of an experimental approach in studying the multiple tensile characterizations as key quality characteristics for several different plastic gear materials related to various parameters in injection moulding process. In this study, emphases are given on a new low-cost mechanism for the testing of the injection moulded plastic spur gear specimens with various teeth module. The testing fixture are developed and validated to provide uniform state of tension with series of plastic gear specimens produced in accordance with the systematically designed of experiment. The effects of changes in the process parameters including melt temperature, packing pressure, packing time and cooling time at three different levels on the elongation at break and ultimate strength of plastic gear is evaluated and studied through the proposed experimental approach.