Comparison of Hologram Calculation Implementations for Wavefront Recording Plane Method Using Look-up Table Method and Direct Calculation Method

Spatial information technology has been widely used for vehicles in general and for fleet management. Many studies have focused on improving vehicle positioning accuracy, although few studies have focused on efficiency improvements for managing large truck fleets in the context of the current complex network of roads. Therefore, this paper proposes a multilayer-based map matching algorithm with different spatial data structures to deal rapidly with large amounts of coordinate data. Using the dimension reduction technique, the geodesic coordinates can be transformed into plane coordinates. This study provides multiple layer grouping combinations to deal with complex road networks. We integrated these techniques and employed a puncture method to process the geometric computation with spatial data-mining approaches. We constructed a spatial division index and combined this with the puncture method, which improves the efficiency of the system and can enhance data retrieval efficiency for large truck fleet dispatching. This paper also used a multilayer-based map matching algorithm with raster data structures. Comparing the results revealed that the look-up table method offers the best outcome. The proposed multilayer-based map matching algorithm using the look-up table method is suited to obtaining competitive performance in identifying efficiency improvements for large truck fleet dispatching.

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The Research of a Derivation Calculation Method for the Maximum Power Point in Grid-Connect Photovoltaic System

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.588-589.583 ◽

2012 ◽

Vol 588-589 ◽

pp. 583-586

Author(s):

Yu Xin Wang ◽

Feng Ge Zhang ◽

Xiao Ju Yin ◽

Shi Lu Zhu

Keyword(s):

Calculation Method ◽

Maximum Power Point Tracking ◽

Direct Calculation ◽

Maximum Power ◽

Photovoltaic System ◽

Duty Ratio ◽

Maximum Power Point ◽

Point Tracking ◽

Power Point Tracking ◽

Power Point

A derivation calculation methods for the maximum power point tracking is proposed in this paper. This method is the direct calculation method for the maximum power point tracking, through the calculation of the derivative value of the power to voltage, adjust the change values of occupies emptiescompared, which is used to deduce the voltage and current value, judge whether the derivative of the power to the voltage is zero, if it is ture, the maximum power point is got. Hardware is used the method to regulate the duty ratio of PWM in DC/DC boost circuit ,though once sampling, it can calculate the value of voltage and the duty ratio at maximum power point. The prototype experiments using DSP2812 chip verify that the inverter can better realize the most power tracing, high accuracy, and the system has the high stability.

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