基于Arc Engine的冻土极值深度查询系统的二次开发和应用

利用国家一、二等水准测量规范提供的冻土极值深度基础数据,基于Arc Engine+.net二次开发平台,设计冻土极值深度查询系统。在此基础上,结合晋冀蒙形变监测网阳红线、砂石线等15条水准路线点之记数据,对查询结果进行精度验证,误差均值为+1.16 cm,方差为1.70 cm2,满足埋石工作的精度要求。     

Distribution and controlling factors of phytoplankton assemblages in a semi-enclosed bay during spring and summer

The phytoplankton assemblages' patterns and their correlation to environmental factors were studied in Bohai Bay during spring and summer. Two zones, the northern (NWA) and southern (SWA) water area, were identified by cluster analysis based on their physical and chemical properties. Principal component analysis (PCA) showed that more phytoplankton species was found in the SWA with low nutrient concentration, while high phytoplankton abundance occurred in the NWA with high nutrient concentration. The seasonal variability in phytoplankton can be explained by water temperature, nutrient, and hydrodynamic conditions (includes mixing during spring and stratification during summer). Results of redundancy analysis (RDA) showed that silicate (SiO(4)) and soluble reactive phosphorus (SRP) were the most important environmental factors influencing the phytoplankton distribution during spring and summer, respectively. Hydrodynamics condition plays a key role in controlling variation of the environmental factors, which determined phytoplankton distribution in Bohai Bay.     

渭河盆地地裂缝群发机理及东、西部地裂缝分布不均衡构造成因研究

利用渭河盆地2001—2008年高精度GPS监测资料,结合区域构造特点建立了渭河盆地有限元动力学模型,基于此研究了区域现今地壳应力场特征,深入分析了构造应力场与盆地内地裂缝群发之间的内在关系,首次基于空间大地测量定量的揭示出了区域构造应力场与盆地内地裂缝群发的内在动力学联系,及盆地东、西部地裂缝分布不均衡的根本成因.研究结果表明:渭河盆地现今地壳应力场差异性显著,主要呈现出中、东部以NW-SE向拉张为主,西部则以NW-SE向压缩应力为主,整体具有相对左旋运动趋势,与区域以往长期构造变形具有较好的继承性;分析揭示出区域NW-SE向拉张构造应力正是盆地内中、东部地裂缝群发的力源机制,而盆地内差异性构造应力场也正是导致盆地东、西部地裂缝发育不均衡的根本原因所在,由此进一步证实了渭河盆地地裂缝的强构造属性,其是由活断层在上述力源机制作用下,以蠕滑形式错断地层使土层破裂而形成的.本文研究结果为盆地地裂缝灾害防治、城市安全建设提供了重要信息.     

小孔径台阵垂直分量P波接收函数研究及应用

尝试用垂直分量P波接收函数技术,分离莫霍面多次反射透射震相PpPmp,以此确定台阵下方的地壳厚度．利用兰州小孔径台阵记录的16次深远地震资料,分离了PpPmp震相,根据其到时计算台阵下方的地壳厚度约(51.6plusmn;1.8) km,与前人研究结果一致．      

云南水氡群体异常特征

采用非均匀度方法,分别提取滇西北、滇中北、滇西南、滇东南和滇东北地区水氡观测资料的地震前兆群体异常。结果表明,该方法能满足水氡观测点所在地区成组中强地震的中、短临预报要求;且该方法能自动识别异常,排除人为主观影响,便于在其他震区进行预报效能检验。     

Assessing environmental risks through fuzzy parameterized probabilistic analysis

A fuzzy parameterized probabilistic analysis (FPPA) method was developed in this study to assess risks associated with environmental pollution-control problems. FPPA integrated environmental transport modeling, fuzzy transformation, probabilistic risk assessment, fuzzy risk quantification into a general risk assessment framework, and was capable of handling uncertainties expressed as fuzzy-parameterized stochastic distributions. The proposed method was applied to two environmental pollution problems, with one being about the point-source pollution in a river system with uncertain water quality parameters and the other being concerned with groundwater contaminant plume from waste landfill site with poorly known contaminant physical properties. The study results indicated that the complex uncertain features had significant impacts on modeling and risk-assessment outputs; the degree of impacts of modeling parameters were highly dependent on the level of imprecision of these parameters. The results also implied that FPPA was capable of addressing vagueness or imprecision associated with probabilistic risk evaluation, and help generate risk outputs that could be elucidated under different possibilistic levels. The proposed method could be used by environmental managers to evaluate trade-offs involving risks and costs, as well as identify management solutions that sufficiently hedge against dual uncertainties.     

基于星载GPS的HY-2卫星高精度精密定轨模拟研究(英文)

HY-2卫星是我国第一颗测高卫星,其径向定轨精度要求厘米量级,搭载了星载GPS接收机。目前HY-2还处于测试阶段,没有公布观测数据。为了确定基于星载GPS的HY-2精密定轨流程及其定轨精度,本文模拟了HY-2卫星星载GPS观测数据,结果表明HY-2星载GPS天线每个历元至少观测7颗GPS卫星。给出了基于星载GPS的精密定轨流程,分别采用简化动力学方法和动态几何法进行了精密定轨实验。对于相位1mm和3mm随机误差的相位观测数据,简化动力学法和动态几何法定轨都能够实现厘米量级的径向精密定轨,几何法定轨精度略低于简化动力定轨。地球重力场模型是影响HY-2卫星精密定轨的重要因素,本文对不同阶次的重力场模型EIGEN2、EGM96、TEG4和GEMT3进行了简化动力学定轨实验,高于50阶次的重力场模型都能够实现厘米级径向精密定轨,主要原因在于大量的高精度星载GPS观测数据和重力场模型精度的提高。     

香鱼(Plecoglossus altivelis)排卵后卵内油球、酶活、丙二醛及受精率、孵化率的变化

以香鱼卵母细胞为研究对象,采用观察卵内油球、有关酶的活力、以及卵的受精率和孵化率等变化的方法,研究了香鱼卵母细胞长时效演化的相关机理,结果表明,随着香鱼卵在腹腔内保存时间的延长,卵内油球从0h的油球直径≤10μm,且均匀分布,逐渐融合增大,至108h增大到120μm,油球数仅有5—6个。同时,SOD、POD的活力及MDA含量均呈先升后降的变化趋势,最大峰值分别出现在60h、36h和24h。随着油球和酶活的变化,卵子质量逐渐下降,表现为受精率和孵化率的降低:排卵后24h、48h、72h、96h的受精率分别为94.37%、88.19%、50.20%、10.83%,孵化率分别为85.78%、68.14%、25.54%、0.53%。     

Vision-based system of AUV for an underwater pipeline tracker

This paper describes a new framework for detection and tracking of underwater pipeline,which includes software system and hardware system.It is designed for vision system of AUV based on monocular CCD camera.First,the real-time data flow from image capture card is pre-processed and pipeline features are extracted for navigation.The region saturation degree is advanced to remove false edge point group after Sobel operation.An appropriate way is proposed to clear the disturbance around the peak point in the process of Hough transform.Second,the continuity of pipeline layout is taken into account to improve the efficiency of line extraction.Once the line information has been obtained,the reference zone is predicted by Kalman filter.It denotes the possible appearance position of the pipeline in the image.Kalman filter is used to estimate this position in next frame so that the information of pipeline of each frame can be known in advance.Results obtained on real optic vision data in tank experiment are displayed and discussed.They show that the proposed system can detect and track the underwater pipeline online,and is effective and feasible.     

Ecological effects of co-culturing sea cucumber Apostichopus japonicus (Selenka) with scallop Chlamys farreri in earthen ponds

Monthly changes in sedimentation and sediment properties were studied for three different culture treatments: sea cucumber monoculture (Mc), sea cucumber and scallop polyculture (Ps-c) and scallop monoculture (Ms). Results indicated that the survival rate of sea cucumber was significantly higher in Ps-c cultures than in Mc cultures. Sea cucumber yield was 69.6% higher in Ps-c culture than in Mc culture. No significant differences in body weight and scallop shell length were found between Ps-c and Ms cultures. The mean sedimentation rate of total particulate matter (TPM) was 72.2 g/(m2 d) in Ps-c cultures, with a maximum of 119.7 g/(m2 d), which was markedly higher than that of Mc (mean value). Sedimentation rates of organic matter (OM), total organic carbon (TOC), total nitrogen (TN) and total phosphorus (TP) in Ps-c cultures were also significantly higher than those in Mc cultures. TOC and TN contents of sediment increased rapidly in the first 5 months in Ms cultures and remained at a high level. TOC and TN contents in Mc and Ps-c cultures decreased during sea cucumber feeding seasons and increased during sea cucumber dormancy periods (summer and winter). The study demonstrates that co-culture of sea cucumber and scallop in earthen ponds is an alternative way to alleviate nutrient loads and improve water quality in coastal aquaculture systems. Moreover, it provides the additional benefit of an increased sea cucumber yield.