Research on the Design of Disaster Prevention Plan for 22km Ultra-long Highway Tunnel with Multiple Intersections

The Tianshan Shengli Tunnel is currently the longest high-altitude highway tunnel. In order to ensure the safe operation of the tunnel, the SES software is used to investigate the wind speed laws in the tunnel, and the tunnel is divided into 16 disaster prevention sections based on the shaft and critical wind speed. The principles of disaster prevention and rescue of Tianshan Shengli Highway Tunnel are given, and the emergency treatment process of tunnel disaster prevention and rescue is given. The disaster prevention and rescue plan of Tianshan Shengli Tunnel from fire occurrence, personnel and vehicle evacuation, and fire treatment are discussed in detail

Horizontal well fracturing technology for reservoirs with low permeability

The horizontal well stress distribution and the rock failure criterion constitute a fracture initiation mathematical model, which was solved by the iteration method. Minimum horizontal principal stress and vertical principal stress have different influences on the fracture initiation pressure when the horizontal well orientation angle is different: the fracture is least likely to initiate when the angle is 0 and is easiest to initiate when the angle is 90°. The simulation result of 3-D hydraulic fractures propagation model matches well with the Fracpro-PT software, and it is suitable to simulate horizontal well fractures propagation. If the fracture interval is long, a multifracture propagation model could be built taking into account of the fractures interaction and the single fracture propagation model. Field horizontal well fracturing technology can be summarized as limited entry treatment and staged fracturing treatment, the limited entry treatment is simple with smaller reformation intensity; the staged fracturing treatment has higher reformation intensity but requires advanced facilities. The fracturing technology should be chosen according to the field situation. Key words: horizontal well, fracturing, fracture initiation, fracture propagation, field technolog

Study on High energy efficiency photovoltaic facility agricultural system in tropical area of China

The photovoltaic facility agriculture is developing rapidly in recent years, but there are many problems brought out, even in some important demonstration projects, due to the lack of standards. In order to solve some of these problems, we set up a photovoltaic facilities agricultural system in Guilinyang University City, Haikou, China and make an in-depth study on the photovoltaic facility agricultural system and its related problems. In this paper we disclose some of the experimental results. We plant corianders under two kinds of solar cell panels and general double glass assembly already sold on the market. Experiments showed that the square format cell panels are much better than row type, and the next one is general double glass assembly sold on the market, the last is the case without any shelter. 30 days after planting, the height of coriander plants are 50mm, 30mm, 23mm and 20mm correspondingly. The two typical solar cell panels have gaps between cells, and can save much more energy and improve power generation efficiency, we arrange the panels at optimum tilted angle, and design the system as open structure to save more energy. The photovoltaic facilities agricultural system we set up in Guilinyang University City can achieve much high solar energy efficiency than others and has broad application prospects

Impacts of Climate Change on the Mean and Variance of Indica and Japonica Rice Yield in China

The overall goal of this study was to examine the impacts of climate change on the mean and variance of rice yields in China by using historical climate and crop data. An econometric model was established to estimate Just–Pope stochastic production functions and identify the potential impacts of climate change on the mean and variance of rice yields by type, keeping other factors constant. Based on the estimated production functions, the contribution rate of climatic factors to rice yield was then assessed by conducting the growth accounting of yields over the past 30 years. The results showed that both the mean rice yield and the yield variability were influenced by changes in the mean climate conditions and climatic variance. In the future, the impacts of climate change on rice yields will depend on local regions’ present climatic conditions. The results have implications for improving the adaptation capacity of rice production