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On dynamic embedded Web server, cgi program is adopted to complete the required workflow. Due to the resource limitation of embedded systems, the performance of embedded Web server is an important issue. To address this problem, we combine cgi with Javascript and make them collaboratively running to satisfy the requirement of embedded application. On embedded server, cgi processes the parameters submitted by client pc and appends the results to the end of HTML page. On client IE, the Javascript embedded in HTML page will parse the results and displayed on the right place of Web page. We also designed a method that detach cgi with business logic and driver interface. In this way cgi can send parameter to driver application indirectly by exchanging parameters through Linux shellt. This enables cgi and driver application to be debugged separately.

An in situ experiment was conducted in an evergreen broad-leaved forest in southwestern Sichuan to study the responses of litter decomposition and nutrient release to simulated nitrogen deposition. Four treatments were installed, i.e., null level (CK), low nitrogen level (LN, 50 kg N x hm(-2) x a(-1)), moderate nitrogen level (MN, 100 kg N x hm(-2) x a(-1)) and high nitrogen level (HN, 150 kg N x hm(-2) x a(-1)). The results showed that it would take 4.72-6.33 years to decompose 95% of litter mass, with the highest decomposition rate in CK and the lowest one in HN. After 365 days, the litter decomposition rate in N-amended treatments was lower than that in CK, but significant difference was only observed between HN and CK (P0.05). The remained C was higher, and the remained N and K were significantly higher in N-amended treatments than in CK (P0.05). The remained P was also higher in N-amended treatments than in CK, but significant difference was only observed between LN and CK (P0.05). Compared with CK, all N-amended treatments had a 3.9%-23.7% increase of litter C/N ratio. During litter decomposition, element N featured a pattern of accumulation at early stage and release later, while C, P and K released all the time. Nitrogen deposition inhibited both the nutrient release from the litter and the decomposition of its lignin and cellulose. The effects of nitrogen deposition on litter decomposition in the forest changed from positive to negative as time passed, and the negative effect could be strengthened with the increase of deposited nitrogen concentration.

By the method of strip transect sampling, the density, height, basal diameter, and components biomass of Abies faxoniana seedlings (Hor = 100 cm) lived in the forest gap (FG) and under the forest canopy (FC) of subalpine natural coniferous forest in West Sichuan were investigated, and the relationships among different components biomass were analyzed. The results indicated that the density and average height (H) of A. faxoniana seedlings were significantly different in FG and under FC, with the values being 12 903 and 2 017 per hectare, and 26.6 cm and 24.3 cm, respectively, while no significant differences were found in average basal diameter (D) and biomass. The biomass allocation in seedling's components was markedly affected by forest gap. In FG, the biomass ratio of branch to trunk (BRBT) reached the maximum (1.54) at 12th year, and then, declined and fluctuated at 0. 69. Under FC, the BRBT was increased with seedlings growth, and exceeded 1.0 at about 15th year. The total biomass and the biomass of leaf, stem, shoot and root grown in FG and under FC were significantly linearly correlated with D2H. There were significant positive correlations among the biomass of different seedling's components.

How to construct an accurate interatomic potential function is an important and basic problem in the simulation procedure. Using first-principles method, the single atom energies in different lattice constants are calculated to achieve the ground state curves of Au and Ag. These energies are calculated in the Perdew and Zunger form of the local-density approximation ultra-soft pseudo potentials. The cut-off energies of the plane wave bases of Au and Ag are set to be 320 eV and 300 eV respectively, which are sufficient for their full converge. The Brillouin zone is all sampled with a 12×12×12 Monkhorst-Pack mesh of k points for Au and Ag. Allowable error in total energy is smaller than 1×10-6 eV per atom. The lattice cohesive energies in different lattice constants are calculated to achieve the lattice energy and atom distance curves after subtracting the value of ground state energy from each of these energy. Then the accurate inversion potential curves are obtained according to the Chen-Möbius inversion theory and self-compiled program. Based on the fitting consequences of inversion potential curves, using different potential function formulas, a double exponential potential function to fit the inversion potential is presented. This function provides the accurate formulas and parameters for the following research. Moreover, the phonon spectra and the densities of states of Au and Ag are calculated respectively by using the inversion potential data, the embedded atom method (EAM) potential theory and first principles method to verify the reliability of the inversion potential. The comparison of the results among the three methods shows that the tendencies of these curves are similar. But they still have some deviations especially in the range of high frequency. However these curves indicate that the inversion potential can reasonably reflect the interaction between atoms. Meanwhile, the inversion potential method has great advantage in calculation quantity compared with the EAM potential method. The inversion method needs less time in calculation. In addition, the thermal expansion coefficients, the elastic moduli and the Grüneisen constants of Au and Ag are also calculated based on the fitting formulas and parameters. The results agree well with the experimental data, which implies that these inversion potentials are effective and accurate.

This paper presents a Z-source inverter for photovoltaic (PV) grid-connected generating system. The Z-source inverter employs a unique LC network to couple the inverter power circuit to the diode front end and can be shoot through to boost the DC link voltage. In order to explain the operating principle, the entire control configuration is analyzed. By controlling sinusoidal modulation index, the grid-connected current inner loop is adopted, which ensures the system working in limit power factor. The Z-source capacitor voltage outer loop is adopted, which ensures the voltage stabilization. By controlling the shoot-through duty cycle, the PV array output voltage is controlled and the maximum power point tracking (MPPT) is realized. Lastly, a 3 kW Z-Source inverter circuit has been built and the experiment results have validated the operating principle.

The systematic position of Paraixeris humifusa (Asteraceae) is hard to define, because the circumscription of Paraixeris , Youngia and Crepidiastrum , three closely related genera in subtribe Crepidinae (Cichorieae), is not clear. This paper reports on the relationships between 30 species in subtribe Crepidinae, based on an analysis of nucleotides from one nuclear (ITS) and three chloroplast DNA regions ( trnL - F , rps16 and atpB - rbcL ). The phylogenetic analyses used maximum parsimony with maximum likelihood inference. The monophyly of Crepidiastrum in the most recent generic classification of Shih & Kilian (2011) is explored. The results show that 12 species in Crepidiastrum constitute a monophyletic group, and that Paraixeris humifusa should be treated as Youngia humifusa.