GYD-300型全液压动力头工程钻机的研制

GYD-300型全液压动力头工程钻机为全液压驱动,动力头反循环式机型。液压系统采用插装阀集成结构,电液复合操作。使用PC控制监测系统,适时检测孔底各相关压力,对不同地层进行范围设置,实现钻进过程中孔底的自动、手动恒压钻进。重点介绍了该钻机的结构特点、实验情况、主要技术参数等。     

GPS变形监测平差计算及不确定度分析

全球定位系统（GPS）是一种全天候、高精度的连续定位系统,它以速度快、方法灵活多样、操作简便等优势被广泛应用于工程测量和变形监测中。结合水厂铁矿GPS边坡变形监测实例,对GPS监测网的星历预报、基线向量平差计算、网平差计算、结果及残差不确定度进行了细致分析研究,以验证GPS技术在边坡变形监测中的可靠性和精度。     

浙江省小流域山洪灾害临界雨量确定方法分析

小流域山洪灾害具有突发性,预测预警难度较大.本文结合浙江省小流域山洪灾害防御的实践经验,研究提出了以水位反推法计算临界雨量,简单实用,具有较好的实践价值和推广意义.     

卫星海洋遥感的发展和预报中心遥感应用

本文简要介绍了卫星海洋遥感的发展情况和可获得的海洋气象观测数据,介绍了预报中心卫星遥感的发展历史和现今状况,以及为海洋环境监测和预报提供的海洋遥感信息产品,并给出了部分产品示例.     

基于EOF分析对南海西北海域水体光谱特性的研究

This study presents an analysis of the spectral characteristics of remote sensing reflectance(R_(rs)) in northwestern South China Sea based on the in situ optical and water quality data for August 2018.R_(rs)was initially divided into four classes,classes A to D,using the max-classification algorithm,and the spectral properties of whole R_(rs) were characterized using the empirical orthogonal function(EOF) analysis.Subsequently,the dominant factors in each EOF mode were determined.The results indicated that more than 95% of the variances of R_(rs) are partly driven by the back-scattering characteristics of the suspended matter.The initial two EOF modes were well correlated with the total suspended matter and back-scattering coefficient.Furthermore,the first EOF modes of the four classes of R_(rs)(A-D R_(rs)-EOF_1) significantly contributed to the total variances of each R_(rs) class.In addition,the correlation coefficients between the amplitude factors of class A-D R_(rs)-EOF_1 and the variances of the relevant water quality and optical parameters were better than those of the unclassified ones.The spectral shape of class AR_(rs)-EOF_1 was governed by the absorption characteristic of chlorophyll a and colored dissolved organic matter(CDOM).The spectral shape of class B R_(rs)-EOF_1 was governed by the absorption characteristic of CDOM since it exhibited a high correlation with the absorption coefficient of CDOM(a_g(λ)),whereas the spectral shape of class C R_(rs)-EOF_1 was governed by the back-scattering characteristics but not affected by the suspended matter.The spectral shape of class D R_(rs)-EOF_1 exhibited a relatively good correlation with all the water quality parameters,which played a significant role in deciding its spectral shape.     

Seasonal and Spatial Variations of Total Mass Flux around Coral Reefs in the Southern Ryukyus,Japan

Total mass flux, size distribution of sediment particles and some chemical components such as total carbon (TC), total nitrogen (TN) and calcium carbonate (CaCO₃) were monitored monthly using a multi-cup sediment traps at seven coral reef sites (6 reef flat and 1 reef slope) of the Marine Protected Areas around Ishigaki, Kohama, Kuroshima and Iriomote Islands in the southern Ryukyus, Japan from September 2000 to September 2001. The size distribution of trapped sediments revealed mostly uni-modal fine sand to mud in the reef flat and gravelly to coarse sand in the reef slope. The total mass flux ranged between 0.54 to 872 gm⁻²d⁻¹, and showed a pronounced seasonality (high in summer-autumn and low in spring) at each site, which was consistent with the rainfall and typhoon regime. Exceptionally high values were observed on the reef slope (Iriomote) in February–March 2001 (1533 gm⁻²d⁻¹) owing to a large amount of bottom sediment re-suspension. On the reef flat (Todoroki South and North; Ishigaki), values obtained in July–August 2001 (872 gm⁻²d⁻¹) and August–September 2001 (800 gm^{− 2}d⁻¹) indicate the high terrestrial discharge from Todoroki River. Trapped sediment particles consist of CaCO₃ (1.2–27.1%) and a non-carbonate fraction (98.8–72.9%), which contains total carbon (4.9–26%), carbonate carbon (CO₂-C) (0.2–3.1%) and non-carbonate carbon (NC-C) (7.9–25.6%). Total nitrogen content was in the range 0.02–0.48%. TN is contained mainly in the carbonate fraction and NC-C may be contained in the non-carbonate fraction. The low TN/OC ratio of the trapped sediments suggests that they were mostly of terrestrial origin and that both fractions migrated. The high total mass flux derived from Todoroki River exceeded the threshold at which a lethal effect on coral community is caused. The results stress the importance of conducting seasonal studies of sedimentation over more than one year and at more than one location in south Japan coral reef ecosystems to gain an understanding of the processes controlling the total mass fluxes and their nutrients content, also to develop an awareness of how to prevent the damage of coral reef ecosystems and, if it does occur, to allow mitigation measures to be undertaken.     

气象卫星用于近海污染监测及赤潮预报方法探索

近年来，由于工农业和沿海养殖业的发展，我国近海污染逐年加重，赤潮发生频次增加。因此，监测近海污染和赤潮发生预报方法研究势在必行。本文用ＮＯＡＡ／ＡＶＨＲＲ数据，分析近海水域污染状况，并探索赤潮发生的预报方法。     

Remote Sensing Analysis of the Suspended Sediment Transport in Lingdingyang

- The data of landsat TM of multi-temporal for Lingdingyang Estuary, Pearl River in China is firstly used with suspended sediment concentration of field measurement to establish a correlative model equation. After the ratio processing of TM data and atmospheric correction, the images of suspended sediment concentration of different temporals are exported from the image processing systems AREIS II and III. These images express the characteristics of suspended sediment distribution, the mode of sediment transport and the extent of dispersion under the actions of tidal current and wind condition of different seasons.     

太阳反射光对海洋水色卫星遥感的影响研究

海洋水色卫星遥感的关键是水色图像资料的利用率。受到太阳反射光的影响使图像饱和是水色卫星图像的主要噪声之一。笔者首先论述了卫星海洋水色遥感中到达水色扫描仪的太阳反射光（即太阳耀光）的辐射量计算模式；然后介绍了产生太阳耀光模拟图像的全过程，并对我国FY－1B、美国的SeaSTAR和台湾省的ROCSAT－1号卫星作了全轨道下的太阳耀光模拟图像；最后，讨论了影响太阳耀光的主要因素，同时提出了减小太阳耀光提高海洋水色卫星遥感图像利用率的建议。     

海水叶绿素α浓度遥感测量的实验研究

本文描述了1989年11月在青岛即墨岙山养殖基地所做的海水叶绿素σ浓度遥感测量的基础实验。该实验获得了高浓度叶绿素α含量的海水反射光谱。该反射光谱的特征波段为:波谷在485nm;波峰在450nm 和535nm;“节点”在572nm.根据该实验数据选取了叶绿素α浓度两种双波段估算模式.分析结果表明;两种模式的精度都在50%以上,且双波段反射率的差值法优于双波段反射率比值法.