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Jun MENG Gangyi DING Laiyang LIU
In view of the different spatial and temporal resolutions of observed multi-source heterogeneous carbon dioxide data and the uncertain quality of observations, a data fusion prediction model for observed multi-scale carbon dioxide concentration data is studied. First, a wireless carbon sensor network is created, the gross error data in the original dataset are eliminated, and remaining valid data are combined with kriging method to generate a series of continuous surfaces for expressing specific features and providing unified spatio-temporally normalized data for subsequent prediction models. Then, the long short-term memory network is used to process these continuous time- and space-normalized data to obtain the carbon dioxide concentration prediction model at any scales. Finally, the experimental results illustrate that the proposed method with spatio-temporal features is more accurate than the single sensor monitoring method without spatio-temporal features.
Masashi KOUDA Ryuji HIRASE Takeshi YAMAO Shu HOTTA Yuji YOSHIDA
We deposited thin films of thiophene/phenylene co-oligomers (TPCOs) onto poly(tetrafluoroethylene) (PTFE) layers that were friction-transferred on substrates. These films were composed of aligned molecules in such a way that their polarizations of emissions and absorbances were larger along the drawing direction than those perpendicular to that direction. Organic field-effect transistors (OFETs) fabricated with these films indicated large mobilities, when the drawing direction of PTFE was parallel to the channel length direction. The friction-transfer technique forms the TPCO films that indicate the anisotropic optical and electronic properties.
Chunxiao LI Weijia CHEN Dawei HE Xuelong HU Shigeru SHIMAMOTO
Vehicles' speed is one of the key factors in vehicle travel efficiency, as speed is related to vehicle travel time, travel safety, fuel consumption, and exhaust gas emissions (e.g., CO2 emissions). Therefore, to improve the travel efficiency, a recommended speed calculation scheme is proposed to assist driving in Vehicle Ad hoc networks (VANETs) circumstances. In the proposed scheme, vehicles' current speed and space headway are obtained by Vehicle-to-Roadside unit (V2R) communication and Vehicle-to-Vehicle (V2V) communication. Based on the vehicles' current speed and adjacent vehicles' space headway, a recommended speed is calculated by on-board units installed in the vehicles, and then this recommended speed is provided to drivers. The drivers can change their speed to the recommended speed. At the recommended speed, vehicle travel efficiency can be improved: vehicles can arrive at destinations in a shorter travel time with fewer stop times, lower fuel consumption, and less CO2 emission. In particular, when approaching intersections, vehicles can pass through the intersections with less red light waiting time and a higher non-stop passing rate.
I-Fong CHEN Chai-Mei PENG Ching-Wen HSUE
This paper presents an analytical model for the electromagnetic radiation in multi-microstrip lines covering the frequency range from 30 MHz to 1 GHz. The radiated emissions of multi-microstrip structure can be divided into the summation of radiated emissions of multi-individual microstrip structures. It is done by modelling the imperfect ground effect of the PCBs. Here we present a circuit model based on traditional transmission lines (TMLs) model. For more accurate analysis of the imperfect ground effect in multi-microstrip lines, we will divide the equivalent circuit model into N sections, based on transverse electromagnetic (TEM) assumption, to estimate the electromagnetic interference (EMI) of multi-microstrip lines. The quantitative value of induced current distribution along the ground return path depends on the physical size, geometry and length of ground trace. Measured data are presented to confirm the results of numerical analysis and the computer simulations with a software package based on the Finite Element Method. A knowledge of EMI source mechanism and their relationship to layout geometries is necessary to determine the essential features that must be modelled to estimate emissions in PCBs design.
Richard R. GOULETTE Robert J. CRAWHALL Stanislus K. XAVIER
This paper outlines an approach for specifying emissions performance at the component level. The objective is to move towards an industry specification for radiated emissions from large integrated circuits in order to facilitate cost effective system design for EMI compliance. Simple models of the mechanisms of direct chip radiation are provided based on the physical and electrical structure of large integrated circuits. These models lead to simple algorithms for estimating the total IC radiation based on IC design parameters. These models can be related to proposed emissions limits based on the desired application of the IC. Finally a measurement methodology is described which permits evaluation of the IC's relative to the limits and provides the information required to make detailed simulation models.