强海杂波下机载雷达HRRP舰船长度提取算法

针对机载雷达受海杂波影响难以对舰船目标高分辨距离像(HRRP)长度准确提取的问题,本文提出一种可适用于强海杂波条件下的舰船长度提取算法。首先,根据舰船目标的航迹信息判断舰船运动姿态并估计当前海面舰船运动姿态与斜平面舰船HRRP回波之间的几何映射关系;其次,对HRRP回波进行包络拉齐和方位聚焦,提升目标信噪比;然后,引入图形学处理方法提出一种基于均值滤波与自适应阈值处理的舰船长度提取算法,提升目标边界信息与杂波间的区分度,实现对HRRP长度的准确提取;最后,多组实测数据验证了所提算法可适用于强海杂波,测长平均误差稳定在10%以内,具有稳健的测长精度与工程应用价值。

基于高分辨距离像的空中目标长度提取方法

雷达采用宽频带信号后，从目标接收到的不再是“点”回波，而是沿距离分布开的高分辨距离像。目标高分辨距离像包含一定的目标信息，如目标的长度、几何结构等，为雷达目标识别提供了较好的基础。基于长度是代表目标固有的特征信息之一，文中提出一种基于高分辨距离像的飞机目标长度提取方法，并经外场实验验证了该方法的有效性。

基于高分卫星数据的冰川长度综合提取方法

冰川长度是冰川变化研究中的重要参数.以青藏高原普若岗日冰原为研究对象,基于高分一号卫星遥感影像和数字高程模型数据,利用波段阈值法和目视解译相结合的方法提取冰川边界,综合利用冰川中心线法和冰川主流线法获取冰川长度,并在地理信息系统技术支持下进行了实现.结果表明,提取的冰川长度线与人工数字化的冰川长度线吻合度较好,精度可达97.9%,且执行效率较高.

单芯电缆线断头痕迹实物提取方法

目的研究单芯电缆线这种离散型客体的实物提取方式、涉及的提取工具和最佳提取长度。方法采用模拟实验的方式,选用不同种类的单芯电缆线为客体,以电缆线断头痕迹不发生变化为基准,确定不同实物提取方式或不同种类工具提取单芯电缆线的最短长度。结果单芯电缆线实物提取可采取的方式主要有钳剪和割削两种,其中钳剪提取方式使用的工具为断线钳和线缆剪,割削提取方式使用的工具为钢锯和角磨机;针对直径小于16mm、非金属外护套及绝缘层的单芯电缆线,断线钳剪切提取最佳长度约为55cm,线缆剪剪切提取最佳长度约为70cm,钢锯锯割提取最佳长度约为5cm,角磨机切削提取最佳长度约为5cm。结论割削提取方法是提取电缆线断头的最佳方法;依据提取操作简便性及快捷性,角磨机(或充电式角磨机)为现场提取电缆线断头的最佳工具。

Extracting Vegetation Phenology Metrics in Changbai Mountains Using an Improved Logistic Model

Remotely sensing images are now available for monitoring vegetation dynamics over large areas.In this paper,an improved logistic model that combines double logistic model and global function was developed.Using this model with SPOT/NDVI data,three key vegetation phenology metrics,the start of growing season (SOS),the end of growing season (EOS) and the length of growing season (LOS),were extracted and mapped in the Changbai Mountains,and the relationship between the key phenology metrics and elevation were established.Results show that average SOS of forest,cropland and grassland in the Changbai Mountains are on the 119th,145th,and 133rd day of year,respectively.The EOS of forest and grassland are similar,with the average on the 280th and 278th,respectively.In comparison,average EOS of the cropland is relatively earlier.The LOS of forest is mainly from the 160th to 180th,that of the grassland extends from the 140th to the 160th,and that of cropland stretches from the 110th to the 130th.As the latitude increases for the same land cover in the study area,the SOS significantly delays and the EOS becomes earlier.The SOS delays approximately three days as the elevation increases 100 m in the areas with elevation higher than 900 m above sea level (a.s.l.).The EOS is slightly earlier as the elevation increases especially in the areas with elevation below 1200 m a.s.l.The LOS shortens approximately four days as the elevation increases 100 m in the areas with elevation higher than 900 m a.s.l.The relationships between vegetation phenology metrics and elevation may be greatly influenced by the land covers.Validation by comparing with the field data and previous research results indicates that the improved logistic model is reliable and effective for extracting vegetation phenology metrics.

Preliminary Analysis of Population Genetic Diversity of Cultivated Laminaria japonica Sporophyte via AFLP Technique

The amplified fragment length polymorphic DNA (AFLP) technique was adopted to estimate the population genetic polymorphism among 30 sporophytes of Laminaria japonica collected from a cultivating farm in Rongcheng,China.Three methods were used for genomic DNA extraction from Laminaria japonica sporophyte and only the products obtained using the improved genomic DNA extraction kit method proved qualified for AFLP analysis.The parameters of the method were optimized.Samples of forty milligrams and the cell lysis time of 120 min were suggested to replace the parameters recommended by the manufacturer.Thirty individuals of Laminaria japonica from the same cultivating site were investigated using one pair of selective primers.A total of 21 loci were obtained and 17 of them were polymorphic.The mean percent age of polymorphic loci of this population was 80.95%.The Nei's gene diversity (H) within this population was 0.3028 and the average Shannon's Information index (I) was 0.4498.A genetic distance matrix among different individuals was constructed as well.Through this study,an applicable AFLP genetic analysis working system for Laminaria japonica sporophyte was established.The results of this research also revealed a high level of genetic diversity within the studied population.

Camptotheca acuminata Decne Residue after Camptothecin Extract as a Substrate to Produce Mushroom Spawn

Currently in China,no technically and economically viable methods exist to handle large quantities of Camptotheca acuminata Decne residue(CA residue) after camptothecin extract while there is a great demand for low cost alternatives to replace the cottonseed hull-based materials used in commercial mushroom culture.Hence,it is of importance for camptothecin extract factories and mushroom producers to explore the utilization of CA residue in mushroom industry.We conducted a research to study how partially or completely substituting traditional mushroom substrate by CA residue would influence the mycelial growth in mushroom spawn production.5 mushroom strains from 4 species were used in the test,i.e.,oyster mushroom(Pleurotus ostreatu) strains,Zayou No.1 and Xide 33,needle mushroom(Flammulina velutipes) strain Chuanjin No.3,hairy wood ear(Auricularia polytricha) strain Huang Er No.10,and shiitake(Lentinula edodes) strain Wuxiang.The nutrient element composition and heavy metal contents of CA residue were determined to ensure its safety and to determine its appropriate component in the substrate formulation for mushroom spawn production.The four substrate formulations(one control-CK,and three treatments,named,T1,T2,T3,) contained 0%,40%,79%,and 100% CA residue,respectively,to allow comparison of the fungal mycelial growth.The control(CK) was the popularly used formulation in Chinese commercial mushroom production,comprising of 73% cottonseed hulls,10% sawdust,15% wheat bran,1% lime,1% white sugar(percentage by weight).All mushroom spawns of the five strains in the four treatments were incubated under the same conditions.The results showed that mycelia of the five mushroom strains grew significantly faster on the substrates containing CA residue than on the substrate with no CA residue(CK).There were no significant differences in the mycelial growth rate among treatments containing CA residue for the two oyster mushrooms and the needle mushroom,but mycelial growth rate in treatments T2 and T3 was significantly higher than in treatment T1 for hairy wood ear and shiitake.The results suggest that CA residue can be used to culture oyster mushroom,needle mushroom,hairy wood ear,and shiitake spawn,and the medium containing CA residue can stimulate their mycelial growth.The commercial production of mushroom spawn using CA residue not only brings better economical benefits including lower cost to mushroom producers,but also reduces environmental pollution by providing a means to reduce dumping and piling of CA residue.

A simple method to extract glacier length based on Digital Elevation Model and glacier boundaries for simple basin type glacier

Glacier length is a key morphological element that has many glaciological applications; however, it is often difficult to determine, especially for glaciers that cover larger spatial areas or those that exhibit frequent temporal change. In this paper, we describe a new Arc GIS-based method that can derive glacier flow lines for determining glacier length based on digital elevation model and glacier outlines. This method involves(1) extraction of the highest and lowest points on a glacier,(2) calculation of 10-m contour lines on the glacier from 10 m to 100 m height, and(3) connection of the midpoints of each contour line with the highest and the lowest points in order to create a flow line, which is subsequently smoothed. In order to assess the reliability of this method, we tested the algorithm's results against flow lines calculated using field measurements, analysing data from the Chinese Glacier Inventory, and manual interpretation. These data showed that the new automated method is effective in deriving glacier flow lines when contour lines are relatively large; in particular, when they are between 70 m and 100 m. Nonetheless, a key limitation of the algorithm is the requirement to automatically delete repeated and closed curves in the pre-treatment processes. In addition to calculating glacier flow lines for derivation of glacier length, this method also can be used to effectively determine glacier terminus change.

The influence of Fe extracting as a filler of fiber concrete performance

This research is showing the effect of increasing an Fe extracting from the compression strength, tension and bending moment. The variations in this experiment are the increasing of Fe extracting 0.5%, 1% and 1.5% of concrete volume. Water Cement Ratio （WCR） variation of 0.48, 0.56 and 0.60. The result of increasing 1.5% Fe extracting causes the increasing of tension strength 44.028 kN/cm2, the increasing of slit tension strength 2.226 kN/cm2, the increasing of bending moment 14.81 kN/cm2 from normal concrete. 0.48 WCR produces tension strength, slit tension strength and bending moment more than 0.56 and 0.60 WCR. The increasing of Fe extracting with the distribution variation area and the spread concrete in the tension concrete area produce 3.705 kN/cm2 bending moment higher than the spread fiber in all of concrete area. The 4 cm fiber length produces the higher bending moment than the 2 cm fiber length. The difference is equally 5.185 kN/cm2. The combination result of the examined acting varieties by continuation statistic test gives the result to get the maximum tension and split tensile. It is a concrete combination of increasing 1.5% fiber percentage, 0.48 WCR, full spreading area and the 4 cm fiber length. The maximum bending moment is the increasing of 0.5% fiber percentage, 0.48 WCR, full spreading area and the 4 cm fiber length.

Management of Chenopodium album L. through the Allelopathic Effect of Mangifera indica L.

Chenopodium album is an invasive weed in wheat fields in Egypt. The present study indicated the potentials for utilization of MILAE （Mangifera indica leaves aqueous extract） at different concentrations （5%, 10%, 15% and 25%） to suppress the germination and growth of C. album in Petri dish experiment Results indicated that predictable degrees of inhibition in C album germination and growth rate of seedlings were accompanied with the increase in the concentration of MILAE. PL （Plumule） and RL （radicle） lengths of C. album were negatively affected as the concentration of MILAE increased and the effect was prominent at 25% extract concentration. This study recommended the use of MILAE as strong phytotoxic potential allelochemicals. an alternative bioherbicides, since its leaves extract possess