防风固沙草方格铺设机器人通过性研究

在沙漠沙土物理性能试验的基础上，对轮胎与沙土相互作用力进行计算，得到沙漠牵引车在行驶过程中产生的驱动力，进行了纵向铺草机构滚轮压草阻力试验，依据汽车地面力学理论对草方格铺设机器人的通过性进行了研究，结果表明所设计的机器人在沙漠中具有良好的通过性。     

Surface area processing in GIS for different mountain regions

Surface area is a fundamental parameter derived from terrain analysis in geographical information systems (GIS) for modeling the real world. Therefore, an evaluation of the techniques implemented by GIS models is important in order to obtain reliable area measurements. The study compares two raster-based methods with a TIN-based (triangulated irregular network) method for surface area approximation using a digital elevation model (DEM) with 25 m × 25 m resolution in six mountain regions of Shandong Province, China. Raster-based method Ⅰ calculates surface-area grids from DEMs directly. Eight 3-dimensional triangles connecting the center point of each cell with the center points of the eight surrounding cells are generated and then the areas of the portions of each triangle that lay within the cell boundary are calculated and summed. Raster-based method Ⅱ produces the surface area of each cell directly from the pixel size and the slope value for the pixel. The results demonstrate that the surface areas calculated by raster-based method Ⅰ are equal to those of the TIN-based method. The results of raster-based method Ⅱ are the lowest but the difference in areas between the two raster-based methods decreases with the decrease in terrain complexity. Compared to the method with TINs, raster-based method Ⅱ can do better because it has some advantages, such as neighborhood analysis, more consistent output and faster processing speed. The results also demonstrate that the difference between surface and horizontal areas should be considered if more than 30% of the area of a region has slopes steeper than 18.2 degrees.     

吉林省东部山区蓝莓棚式防寒技术的研究

以美登等4个蓝莓品种为试验材料,在吉林省东部山区进行冬季棚式防寒新技术与覆土防寒效果的比较研究,结果表明：棚式防寒较覆土防寒可节约成本4 485元·hm-2,果实产量增加收益12 942元·hm-2,总体收益提高了17 427元·hm-2,经济效益十分显著。     

沉香山药用植物资源初步调查

沉香山位于粤西沿海地区,地处重要的南药产地,区内植物资源丰富.经初步调查发现,药用植物种类达406种(其中苏铁蕨、土沉香、金毛狗等属珍稀濒危物种),分属106科;植物的药用范围十分广泛,遍及19大类.     

环境监管研究现状分析与展望

综述了我国环境监管的现状,分别针对目前的固定源、移动源引发的环境风险事故,从风险识别、风险防范、应急救援等角度进行了归纳。对我国政府部门的监管措施及效能现状进行了分析,提出了诸多存在的问题,为今后构建完善的环境监管体系提供参考。     

Simple Analysis of the Thermal Environment in Chongqing

There are a series of city environmental problems especially in the mountain city along with the city fast development. In recent decade, many scholars have studied the urban heat island, the urban temperature, the urban wind field, the precipitation and the urban visibility etc. But the urban thermal environment has not been settled radically. All the measures have not been used in the practice. And the researches in thermal environment of the mountain cities are very few. So the authors consider Chongqing as the researching object. Chongqing is one of the typical mountain cities in the semi-tropical. Sequentially we find out the characteristic of the thermal environment in the mountain city. Further the authors seek for the measures to plan and build ecological city. They conclude that CFD can be used in the simulation of urban environment, and use the result of simulation in urban planning is possible. The thermal environment in the center of Chongqing needs to be improved.     

高山冷凉地区松花菜品种适应性评价

筛选适宜陕西太白高山冷凉地区种植的松花菜品种,为该地区松花菜品种推广提供科学依据。引进15个供试松花菜品种,以高山宝75为对照品种,运用DTOPSIS法对参试松花菜多个性状进行适应性评价。结果表明,台松90、松不老80、正能松80、正能松90和松美80综合性状均优于对照品种。其中,松不老80主要性状接近理想值,综合排名第1位,表现高产,稳产,品质优良;台松90综合排名第2位,品种综合性状表现较优;正能松80综合排名第3位,可作为优良品种推广。综上所述,15个参试松花菜品种中,台松90、松不老80和正能松80综合性状表现优良,适宜在陕西太白及周边生态环境相似的地区应用推广。     

Investigation and Reference of the Mountain Tourist Hotel in Western Sichuan

Tourist hotel is the main supporting establishment for the touring industry.The authors investigated several important mountain beauty spots in the west of Sichuan province,some problems were found and their reasons were studied.Then,some common characters of mountain tourist hotels were summarized.It is hoped to give some reference to congenial buildings in west China in the future.     

Performance Analysis of MIPv4 Regional Registration Combined with Low Latency Handoffs

The mechanism of MIPv4 regional registration and the low latency handoff protocols are introduced. Ways and procedure of pre-registration handoff and post-registration handoff are discussed also. The authors analyze the performance of the low latency handoff protocols combined with low latency handoffs over a wireless access based on IEEE 802. 11 standard in a tree-like network topology. The performance of pre-registration and post-registration scheme is given by simulation.