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101.
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   
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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   
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Distinct differences in in vivo stability of the two diastereomeric C-Functionalized CyDTPA chelating agents, (CHX-A DTPA and CHX-B DTPA, both racemates), as recently reported prompted further investigation as to why differences in configuration produced striking effects on the in vivo stability of their yttrium complexes. To this end, the four individual component stereoisomers of CHX-A and CHX-B were synthesized and ability to bind yttrium was investigated both in vitro and in vivo.  相似文献   
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An expression cloning screen was used to isolate a novel gene homologous to the extracellular cysteine-rich domain of frizzled receptors. The gene (which we called sizzled for secreted frizzled) was shown to encode a soluble secreted protein, containing a functional signal sequence but no transmembrane domains. Sizzled (szl) is capable of inhibiting Xwnt8 as assayed by (1) dose-dependent inhibition of siamois induction by Xwnt8 in animal caps, (2) rescue of embryos ventralized by Xwnt8 DNA and (3) inhibition of XmyoD expression in the marginal zone. Szl can dorsalize Xenopus embryos if expressed after the midblastula transition, strengthening the idea that zygotic expression of wnts and in particular of Xwnt8 plays a role in antagonizing dorsal signals. It also suggests that inhibiting ventralizing wnts parallels the opposition of BMPs by noggin and chordin. szl expression is restricted to a narrow domain in the ventral marginal zone of gastrulating embryos. szl thus encodes a secreted antagonist of wnt signaling likely involved in inhibiting Xwnt8 and XmyoD ventrally and whose restricted expression represents a new element in the molecular pattern of the ventral marginal zone.  相似文献   
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