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31.
Embedded software and hardware implementation system for a human machine interface based on ISOAgLib
Enkhbaatar TUMENJARGAL Luubaatar BADARCH Hyeokjae KWON Woonchul HAM 《浙江大学学报:C卷英文版》2013,14(3):155-166
Modern agricultural machinery demands adoption of embedded electronic and remote sensing technology for precision agriculture.One of the electronic devices commonly used is the virtual terminal(VT) for tractors.A VT’s functions and terminology are described in the ISO 11783 standard.This paper presents a control system design and implementation for a VT and some other electronic control units(ECUs) for agricultural vehicles based on that standard.Hardware and software development for the VT is implemented using the ISOAgLib open library,in the advanced embedded system.The main part of the system is an embedded board based on a Samsung S3C6410 ARM11 core microprocessor with a controller area network(CAN) module.Its working environment is Windows Embedded CE 6.0(WinCE6.0).The ISOAgLib library provides abundant open sources consistent implementation of ISO 11783.It is written in C++ programming language using object-oriented technology.In this paper,we describe an ISO 11783-based tractor control system with a CAN and its implementation in the embedded system.This paper also explains the operation of a CAN-bus device driver in WinCE6.0 and some modifications of ISOAgLib for our target system.The target system consists of the VT,an ECU for the global positioning system(GPS),and an ECU for lighting for an agricultural tractor.The ECU for GPS and the ECU of a light controller are implemented using STM32F107F ARM Cortex M3-based development boards. 相似文献
32.
Ho Wan Ham 《Thin solid films》2010,518(22):6558-6563
Indoline dye sensitizers were designed and studied theoretically to increase molar extinction coefficients in the visible to near infrared region for solar-cell devices. To gain insight into dye sensitizers' structural, electronic, and optical properties, DFT/TDDFT calculations were performed on a series of dye sensitizers derived from the D149. The good agreement between the experimental and TDDFT calculated absorption spectra of the D149 sensitizer allowed us to provide a detailed assessment of the main spectral features of a series of dye sensitizers. Increase in the conjugation length resulted in a more red-shifted spectral response and less positive oxidation potential than that of the D149. The dye with the dimethylfluorene group showed stronger absorption bands due to a large dipole moment. The calculated dipoles for the dye series correlate well with the observed strong absorption bands of the electronic spectra. These results provided useful clues for the molecular engineering of efficient organic dye sensitizers. 相似文献
33.
Young Hoon Lee Myoungsoo Ham Bruce Yoo Jae Sun Lee 《The International Journal of Advanced Manufacturing Technology》2009,41(5-6):568-579
Operations management in a complex manufacturing environment is practiced hierarchically: production planning and scheduling in sequence since the integrated approach is not efficient and practical. Production targets and allocation to the equipment are determined in the planning procedure by considering the only the critical factors, and the detailed scheduling is determined with more information needed to accomplish the production targets provided in the planning step. There is always, therefore, a gap between the planning and scheduling procedure, and some control parameters or factors are used to control those gaps. In this paper an approach connecting two procedures is suggested, which can be applied in the EDS (electrical die sorting) or the probe process in the semiconductor manufacturing. The EDS process requires very flexible operation management since the manufacturing processing time is relatively short and the supply of upstream fabrication and the demand of downstream assembly have to be met simultaneously. Daily planning and scheduling procedure are modeled to minimize the tester change-over within the daily target. Because of the relatively long setup change-over time, daily planning and scheduling have to be performed so that the time needed for the device and probe card change is minimized as possible. Mathematical programming is suggested for the problem, and the modified model is developed which can be solved in a practical computational time on a daily base. The scheduling heuristic with the planning data obtained from the suggested model, is designed, and their performance is evaluated through the computational experiment. 相似文献
34.
35.
In this paper, we introduce a novel standing wave oscillator (SWO) utilizing standing-wave-adaptive tapered transmission lines. This structure enhances Q and lowers phase noise through loss-reducing shaping of the transmission line, such that it is adapted to the position-dependent amplitudes of standing waves. Measurements validate the advantages of the proposed technique. The phase noise of a MOS SWO with the tapered line is 5-10 dB less than that of a uniform-line MOS SWO over a wide range of offset frequencies, centered about 15 GHz. Demonstrating a valuable exploitation of standing wave properties, the novel design concept boosts the potential for the emergence of standing wave oscillators as a useful alternative to the traditional lumped LC oscillator. 相似文献
36.
37.
Sagar V. Kamarthi Soundarr T. Kumara Francis T. S. Yu Inyong Ham 《Journal of Intelligent Manufacturing》1990,1(2):125-140
Neural networks have gained increased importance in the past few years. One of the basic characteristics of neural networks is the property of associative memory. In this paper we study the possibility of using the ideas of neural networks and associative memory in the manufacturing domain, with specific reference to design data retrieval in group technology. A two-layer feed-forward perceptron with backpropagation is simulated on a Vax-8550 to train example parts. The complete scheme along with the simulation results are explained and future directions indicated. 相似文献
38.
Current non-equilibrium distillation models do not explicitly include the coupling between thermal and mass fluxes. We present a calculation model for the coupled transfer of mass and thermal energy in the vapour–liquid region of a binary mixture. The region is modelled as a vapour–liquid interface in between two homogeneous films. The entropy production in the vapour–liquid region can be calculated using both irreversible thermodynamics and the entropy balance. The film thickness ratio is found by requiring the entropy production calculated with the two methods to be equal, while keeping the vapour film thickness fixed. Using a nitrogen–oxygen mixture as example, we show that neglecting the coupling between thermal and mass fluxes can have a large impact on the magnitude and direction of the theoretical (net) fluxes. The size of the impact depends on the vapour film thickness, but it is significant for all thicknesses. By increasing the number of control volumes that is used to represent the liquid and vapour films, we also show that the fluxes depend highly on the resistivity profiles in the films. They depend slightly on the interface resistance. A sensitivity analysis of the transport properties shows that accurate values of the Maxwell–Stefan diffusion coefficients in both homogeneous phases and of the liquid phase heat of transfer are most important. Especially the measurable heat flux at the liquid boundary of the system is sensitive to neglect of coupling, to neglect of the interface resistance and to uncertainties in the transfer properties. 相似文献
39.
An advanced regression scheme is proposed to analyze fine leak batch testing data of multiple MEMS packages. The scheme employs the forward-stepwise regression method to infer the information of leaky packages from a batch test data. The analysis predicts the number of leaky packages and the true leak rate of each leaky package in a progressive manner. The scheme is implemented successfully using an actual batch test data obtained from wafer-level hermetic MEMS packages. An error analysis is followed to define the applicable domain of the scheme. Advanced formulations are also suggested to extend the applicable domain. 相似文献
40.
The formation of N2O in NH3–SCR deNOx reaction over an on-site-used commercial V2O5–WO3/TiO2 catalyst has been measured using an on-line IR system with a modified gas cell. The N2O could be formed by the SCR and NH3 oxidation reactions. These two reactions were particularly enhanced with the on-site-used sample. 相似文献