基于卷积神经网络和高分辨率影像的湿地群落遥感分类——以洪河湿地为例

以洪河国家级自然保护区为研究对象,应用卷积神经网络（CNN）方法进行高分辨率湿地遥感影像的分类研究,并与基于光谱支持向量机（SP-SVM）的方法和基于纹理及光谱的支持向量机（TSP-SVM）的方法进行了对比。结果显示,对于所选取的2个研究区域,CNN分类方法的全局精度高于SP-SVM方法5.61%和5%,高于TSP-SVM方法4.18%和4.15%。尤其对于部分湿地植被的分类精度明显高于SP-SVM和TSP-SVM方法。研究表明,卷积神经网络为湿地识别的精细划分提供了有利的手段。     

Design and on-orbit status of the trigger system for the DAMPE mission

DArk Matter Particle Explorer(DAMPE), the first Chinese astronomical satellite, was successfully launched at the Jiuquan Satellite Launch Center on 2015 Dec. 17. DAMPE consists of four subdetectors: Plastic Scintillator array Detector(PSD), Silicon-Tungsten tracKer-converter(STK), Bismuth Germanium Oxide(BGO) imaging calorimeter and NeUtron Detector(NUD). The global hardware trigger signal, which is generated by hits from the BGO calorimeter and the trigger logic board in the data acquisition system(DAQ), is responsible for event selection and DAQ synchronization of DAMPE. On orbit,to improve the detection efficiency, different trigger logics are used for event selection in different regions of latitude. The DAMPE trigger system compresses the average on-orbit trigger rate to 60 Hz and reduces science data mass to less than 13 GB per day to meet the requirement for the satellite's data link. The whole trigger system has run stably up to now, ensuring excellent on-orbit operation of DAMPE.     

沉积白云石形成条件的试验研究

经过大量试验研究工作，总结出在常温常压条件下，全成碳酸盐矿物的控制因素和形成条件，合成出原白云石（无序白云）等一系列碳酸盐矿物.原白云石经加温加压，在100℃或150℃转化为白云石（有序白云石）.     

Numerical study of harbor oscillations induced by water surface disturbances within harbors of constant depth

Oscillations within an enclosed rectangular harbor and a set of partially opened rectangular harbors with various widths and locations of entrance induced by cubic water surface disturbances with different initial heights and locations are simulated using FUNWAVE 2.0 model. The height and the location of the cubic water surface disturbance refer to its thickness and its relative horizontal position inside the harbor, respectively. The water depth inside and outside all harbors is set to be constant. The aim of this paper is to investigate how different heights and locations of the water surface disturbance and various widths and locations of harbor entrance affect the oscillations inside the harbor. Results show that for the given harbors and the range of the initial height of water surface disturbance studied in this paper, all the response amplitudes of various eigenfrequencies increase linearly with the initial height of water surface disturbance. The variations of the initial location of water surface disturbance along the backwall and sidewall of the harbor can significantly change the transverse and longitudinal oscillation patterns of various modes, respectively. The effects of the variations of the width and location of the harbor entrance on the response amplitudes of various resonant modes both depend on the relative positions of their node lines and antinode lines to the harbor entrance.     

1957~2016年中国农业界限温度时空变化研究

利用中国830个气象站点1957~2016年地面气象观测资料,采用五日滑动平均法和GIS方法确定了近60 a农业界限温度（0℃、5℃、10℃）的初终日期和持续日数,并比较分析1957~1986年和1987~2016年2个时段的≥0℃、≥5℃和≥10℃农业界限温度的初终日期和持续日数的变化情况。结果表明：与1957~1986年相比,1987~2016年中国农业界限温度（0℃、5℃、10℃）的总体变化规律基本一致,即初日提前、终日推迟、持续日数增加,各地区变化幅度不同,东北、华北和青藏高原地区变化幅度最大。中国各界限温度的终日变化幅度均较小,初日和持续日数变化较大。≥0℃初日在东北北部和青藏高原地区分别提前3~9 d和3~15 d,持续日数在东北和华北部分地区分别增加3~15 d和2~18 d,青藏高原部分地区增加4~16 d;≥5℃初日在东北和华中地区分别提前4~9 d和6~13 d,持续日数在东北、华北部分地区分别增加4~13 d和2~14 d,青藏高原地区增加2~23 d;≥10℃初日在东北和青藏高原地区分别提前2~9 d和2~13 d,持续日数在东北和青藏高原地区变化最为显著,分别增加3~15 d和5~25 d。农业界限温度的初终日期和持续日数变化,使作物生育期延长和种植界线北移。     

Regulation of water quality and growth characteristics of indoor raceway culture of <Emphasis Type="Italic">Litopenaeus vannamei</Emphasis>

Two modes of regulating the water quality of experimental ponds in indoor raceway culture of Litopenaeus vannamei were evaluated using simple water treatment facilities. A self-made water purifying net, aeration stone, composite microbe preparation, and Ceratophyllum demersum were placed in the experimental ponds and the culture water was circulated along the raceway inside the pond using a paddle wheel aerator. In addition, the water quality in the experimental pond was improved by draining effluent from the pipeline at the bottom of ponds 7 and 8 (mode I) and exchanging the circulating water in pond 10 (mode II) with the reservoir water in pond 9 using a pump and pipeline. The water quality in the experimental ponds was similar in response to regulation using mode I or mode II. Water quality parameters in the experimental ponds were controlled within a suitable range by simple facilities during culture period without using any chemical treatments. The rich content of dissolved oxygen was maintained by the circular flow and continuous aeration of the pond water. The respective average values of the main water parameters in experimental ponds 7 and 10 in response to regulation of the water quality using modes I and II were as follows: pH 8.17 and 7.99; DO 5.16 mg/L and 5.97 mg/L; COD_Mn 18.45 and 12.61 mg/L; TAN (NH₃-N) 0.854 mg/L (0.087 mg/L) and 0.427 mg/L (0.012 mg/L); NO₂-N 0.489 mg/L and 0.337 mg/L. Moreover, the average body length and body weight of harvested shrimp of pond 7 and pond 10 were 7.56 cm and 8.99 cm, 5.10 g and 8.33 g, respectively. Furthermore, the survival rate, average biomass yield and average condition factor of the shrimp harvested were 70% and 60%, 2.54 kg/m² and 2.14 kg/m², and 0.675 g/cm and 0.927 g/cm, respectively. Linear equations describing the relationship between body length and culture time and cubic or power functions describing the relationship between body weight and body length were obtained based on evaluation of the growth data of shrimps throughout the culture period.     

Free-surface evolution and wave kinematics for nonlinear uni-directional focused wave groups

This paper concerns the propagation of transient wave groups, focused at a point in time and space to produce locally large waves having a range of steepness. The experimental study was carried out in a wave flume at Dalian University of Technology. The numerical simulations were based on a nonlinear boundary integral equation solved by a higher-order boundary element method (HOBEM). Rather than simulate the whole experimental tank, local surface elevation measurements were used to drive the numerical solution from a point less than two wavelengths upstream of the focus position, leading to significant savings in computational time. Excellent agreement is achieved between the water surface elevations and the water particle kinematics measured in the experiments and those predicted numerically at wave group focus, even for near-breaking waves up to a steepness of kA=0.405 for which even locally matched 2nd-order theory is inadequate. Results based on the linear and 2nd-order theory are also presented in the comparisons. When compared with the first- and 2nd-order solutions, the fully nonlinear wave–wave interactions produce a steeper wave envelope in which the central wave crest is higher and narrower, while the adjacent wave troughs are broader and less deep.     

安丘市国土资源局努力构建“和谐国土”服务品牌

安丘市国土资源局深入贯彻落实科学发展观,围绕市委市政府中心工作,严格依法行政,支持服务发展,通过推行为民服务承诺,创建“和谐国土”服务品牌,扎实推进国土资源管理工作。     

Studies on the ingestion characteristics of giant freshwater prawn, Chinese prawn and giant tiger prawn

ＩＮＴＲＯＤＵＣＴＩＯＮＡｔｐｒｅｓｅｎｔｇｉａｎｔｆｒｅｓｈｗａｔｅｒｐｒａｗｎ (Ｍａｃｒｏｂｒａｃｈｉｕｍｒｏｓｅｎｂｅｒｇｉｉ) ,Ｃｈｉｎｅｓｅｓｈｒｉｍｐ (Ｐｅｎａｅｕｓｃｈｉｎｅｎｓｉｓ)ａｎｄｇｉａｎｔｔｉｇｅｒｐｒａｗｎ (Ｐ .ｍｏｎｏｄｏｎ)ａｒｅｔｈｅｍａｉｎｓｈｒｉｍｐｓｆｏｒｃｕｌｔｕｒｅｉｎＣｈｉｎａ.Ａｓｗｅｋｎｏｗ ,ｆｅｅｄｓｔｕｆｆｃｏｓｔｉｓａｍａｊｏｒｅｘｐｅｎｓｅｉｔｅｍｉｎｃｕｌｔｕｒｅｐｒａｃｔｉｃｅ.Ｏｖｅｒｆｅｅｄｉｎｇｗｉｌｌｎｏｔｏｎｌｙｗａｓｔｅｆｅｅ…     

海产腹足类有机锡化合物的检测方法

三丁基锡(TBT)等有机锡化合物因其毒性及结构上的特点被广泛应用于船舶、网箱渔排等的防污涂料中.它的主要作用是在水体中持久地释放出可以有效杀死海洋污损生物的毒性物质,从而达到防护船舶、渔排等体表的目的[1],然而进入海洋环境的有机锡化合物在防污的同时也会影响到许多非靶生物,并对海洋生态系统的结构与功能产生严重的危害,被认为是迄今为止人为引入海洋环境毒性最大的物质之一[2～4].因此,检测海洋生物体内的有机锡含量成为对有机锡污染生态效应调查与研究不可缺少的手段[5～7].