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Elevation is important for determining the nutrient biogeochemical cycle in forest ecosystems. Changes in the ecological stoichiometry of nutrients along an elevation gradient can be used to predict how an element cycle responds in the midst of global climate change. We investigated changes in concentrations of and relationships between nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg) in the leaves and roots of the dominant tree species, Castanopsis fargesii, along an elevation gradient (from 500 to 1,000 m above mean sea level) in a subtropical natural forest in China. We analyzed correlations between C. fargesii’s above-ground biomass and stoichiometry with environmental factors. We also analyzed the soil and plant stoichiometry of this C. fargesii population. Our results showed that leaf N decreased while leaf K and Ca increased at higher elevations. Meanwhile, leaf P showed no relationship with elevation. The leaf N:P indicated that C. fargesii was limited by N. Elevation gradients contributed 46.40% of the total variance of ecological stoichiometry when assessing environmental factors. Our research may provide a theoretical basis for the biogeochemical cycle along with better forest management and fertilization for this C. fargesii population.

Residential solar photovoltaic (PV) installations have boomed in China over recent years. However, knowledge about the economic performance of residential PV investments is still limited. Therefore, this study attempts to make a complete economic assessment of residential PV systems at the county-level. After a brief description of China’s incentive policies, a model is constructed with economic measures of internal rate of return and payback period based on discounted cash flow. Then, a reference PV system of 5 kWp is investigated in 2181 geographical areas using scenario analysis and sensitivity analysis. There is breakeven for residential PV investments all over China even without incentives. The areas with good performance of residential PV investments are located mostly in Northern China (Shandong and Hebei), Southern China (Guangdong and Hainan), northeast China (Liaoning, Jilin, and Heilongjiang), and southwest China (Sichuan and Tibet). The boom of residential PV installations is likely to recede in 2021 as the population with acceptable profitability declines since the central and local subsidies expire. But some excellent residential PV suppliers have the potential to compensate for the performance decrease in many ways such as increasing annual generation and reducing initial cost. This paper contributes by providing some insights into the economic performance and market of residential PV installations in China.

The Fukeshan Cu (Mo) deposit is a newfound porphyry deposit in the northern Great Xing&rsquo, an Range (GXR), northeast China. In this paper, we present results of chalcopyrite Re&ndash, Os geochronology, microthermometry of the fluid inclusions (FIs), and isotopic (H&ndash, O&ndash, S&ndash, Pb) compositions of the Fukeshan Cu (Mo) deposit. Its ore-forming process can be divided into sulfide-barren quartz veins (A vein, stage I), quartz + chalcopyrite + pyrite veins (B vein, stage II), quartz + polymetallic sulfide veins (D vein, stage III), and barren quartz + carbonate &plusmn, pyrite veins (E vein, stage IV), with Cu mineralization mainly occurred in stage II. Three types of FIs are identified in this deposit: liquid-rich two-phase (L-type) FIs, vapor-rich two-phase (V-type) FIs, daughter mineral-bearing three-phase (S-type) FIs. The homogenization temperatures of primary FIs hosted in quartz of stages I&ndash, IV are 381&ndash, 494 &deg, C, 282&ndash, 398 &deg, C, 233&ndash, 340 &deg, C, and 144&ndash, 239 &deg, C, with salinities of 7.2&ndash, 58.6, 4.8&ndash, 9.9, 1.4&ndash, 7.9, and 0.9&ndash, 3.9 wt. % NaCl equivalent, respectively. FIs microthermometry and H&ndash, O isotope data suggest that the ore-forming fluids were magmatic in origin and were gradually mixed with meteoric water from stages II to IV. Sulfur and lead isotope results indicate that the ore-forming materials of the Fukeshan Cu (Mo) deposit were likely to have originated from Late Jurassic intrusive rocks. The available data suggest that fluid cooling and incursions of meteoric water into the magmatic fluids were two important factors for Cu precipitation in the Fukeshan Cu (Mo) deposit. Chalcopyrite Re&ndash, Os dating yielded an isochron age of 144.7 &plusmn, 5.4 Ma, which is similar to the zircon U&ndash, Pb age of the quartz diorite porphyry, indicating that Late Jurassic quartz diorite porphyry and Cu mineralization occurred contemporaneously.

Farmers’ interest in precision nitrogen (N) fertilization has grown in the inland Pacific Northwest due to significant within-field spatial variability in yield and protein content. Mapping the spatial variability of yield, protein content, and total grain N uptake (Ng) can be a useful tool for post-harvest evaluation of N sufficiency that, in turn, can guide precision N fertilization. We evaluated the applicability of combining RapidEye satellite imagery-derived vegetation indices with topographic variables derived from high-resolution data obtained from proximal sensors to estimate winter wheat yield, protein content, and Ng. Results indicate that the normalized difference vegetation index (NDVI), the normalized difference red edge index (NDRE), terrain curvature, slope, aspect, topographic wetness index, and solar radiation are the most relevant co-variables that contribute to spatial variability of yield and Ng. Yield and Ng exhibited strong relationships with NDVI and NDRE from late June through early July during grain filling stage, with nearly all R2 > 0.6. We found greater yield and Ng values in concave-shaped terrain; 0-5° and 10-20° slopes; and flat, eastern, or northern aspects. In contrast, protein content exhibited weak relationships with vegetation indices and nearly all terrain factors. Prediction models demonstrated that these variables can provide good estimations of yield and Ng, with R2 of 0.848 and 0.864, respectively, and RMSE of 48.47 and 0.0136, respectively. Combining RapidEye-based NDRE with proximal sensor-based topographical factors shows great potential for accurately and efficiently estimating winter wheat yield and Ng, which can help guide N fertilizer management.

Soil organic matter (SOM) is an important component of soils, and knowing the spatial distribution and variation of SOM is the premise for sustainably utilizing soils. The objective of this study was to compare geographically weighted regression (GWR) with regression kriging (RK) for estimating the spatial distribution of SOM using field-sample data in SOM and auxiliary data in correlated environmental variables (e.g., elevation, slope, ferrous minerals index, and Normalized Difference Vegetation Index). Results showed that GWR was a relatively better method and could provide promising results for SOM prediction in comparison with RK. The map interpolated by GWR showed similar spatial patterns influenced by environmental variables and the nonapparent effect of data outliers, but with higher accuracies, compared to that interpolated by RK.

The Rao-Blackwellized particle filter (RBPF) algorithm usually has better performance than the traditional particle filter (PF) by utilizing conditional dependency relationships between parts of the state variables to estimate. By doing so, RBPF could not only improve the estimation precision but also reduce the overall computational complexity. However, the computational burden is still too high for many real-time applications. To improve the efficiency of RBPF, the particle swarm optimization (PSO) is applied to drive all the particles to the regions where their likelihoods are high in the nonlinear area. So only a small number of particles are needed to participate in the required computation. The experimental results demonstrate that this novel algorithm is more efficient than the standard RBPF.

C29H14ClN4O4Pb, triclinic, P1 (no. 2), a =1 0.310(5) A, b =1 0.521(5) A, c =1 2.168(5) A, 0 =8 0.808(5)°, / =8 1.973(5)°, . =7 9.638(5)°, V =1 273.3 A 3

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頁次：4-8本文回顧《圖書館學與資訊科學》創刊經過及編輯情形，並提出未來發展之願景，以檢討過去，策勵來茲。著者參與編輯工作多年，深感為加強國內外之溝通，並謀在圖書館經營理念和實際做法上的交流，希望國內外圖書館從業人員多加報導介紹重要之發展，並介紹優秀的論著， 供國內圖書館界參考。To celebrate the JLIS' twenty-fifth anniversary, the journal's former editor in chief, Professor C.K. Wang, reviews the initial stages of the JLIS, shares and describes the visions and practical challenges of editing the journal. Future perspectives are also elaborated.

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For putting in practice of agriculture engineering development and high–tech application, computer education for agriculture engineers is very important content whatever in university or employment cultivation. As long as advancement in agriculture engineering, many new technologies like digital agriculture, precision agriculture and information agriculture have grown up to be used. But while we deeply discuss computer education used in this field, the next generation new knowledge system in agriculture engineering should be presented, that is “Intelligent Agriculture(IA)” which is new concept based on intelligent control theory used in agriculture complex large system. With this concept, the agriculture system can be designed many close systems with feedback, and all of intelligent technologies combination artificial intelligent, automation control and computer algorithm research will be used in, and whole agriculture system can be realized to intelligent management and control output with advanced detecting technology and network control technology as well as all useful computer integration technologies. According to the connotation of IA, in this paper, the control structure and technology integration modeling describing for IA is discussed firstly. And then, for high technology application in agricultural field under IA, the future computer education supporting to IA for agriculture engineers is discussed. On the other hand, for application in two sides of controllable agricultural environment engineering and open field environment agriculture engineering, the future computer education for engineers will be changed correspondingly in curriculum. Hence, in this paper, the reform of computer education and work training for agricultural engineers are also discussed

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