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101.
提出了全站仪坐标导线外业施测时的检核方法和内业几种严密平差方法。  相似文献   
102.
Juvenile north-temperate and Arctic fishes are faced with trade-offs between energy allocation to growth and energy storage (primarily lipids) prior to over-wintering. We determined classical morphometric (fork length, body weight and condition factor) and biochemical (whole body triglycerides, muscle RNA/DNA ratio, muscle proteins) measures of growth and condition in individual young-of-the-year (YOY) Arctic grayling (Thymallus arcticus). Grayling were collected just prior to over-wintering in late August (approximately 50 days after swim-up) from two natural streams and five locations within a 3.4 km long artificial stream constructed as a fish habitat compensation project and diversion channel for the diamond mining industry in Northwest Territories, Canada (64°45′N). Fork lengths, body weights and whole body triglyceride levels in grayling collected from all sites along the artificial stream were significantly lower than fish collected from one of the natural streams. Condition factor (weight-at-length) was not different among grayling collected from natural and artificial streams. Muscle proteins were lower in grayling collected from four sites along the artificial stream compared to the natural streams. In contrast, muscle RNA/DNA ratios were greater in grayling collected from two sites in the artificial stream compared to natural streams. There were no consistent differences in any variable among grayling collected at the five artificial stream sites or among grayling collected from the two natural streams. The higher RNA/DNA ratios and lower fork lengths, whole body triglycerides and muscle proteins in grayling inhabiting the artificial stream are consistent with energy still being primarily allocated to growth in these fish at this late stage of summer. Individuals that are both larger and possess greater energy storage in the form of triglycerides are more likely to survive the long over-wintering period at this latitude. Our results suggest that YOY grayling using the artificial stream as nursery habitat will likely face increased over-winter mortality, thus raising concerns over the use of fish presence, spawning and rearing as criteria for the initial success of artificial streams as habitat compensation measures in Arctic tundra regions. Further research is needed to determine the potential consequences of reduced size and energy storage in juvenile fishes in order to assess the viability of stream fish habitat compensation and restoration projects associated with industrial development in Arctic tundra regions.  相似文献   
103.
基于反演的衰减补偿方法(英文)   总被引:6,自引:1,他引:5  
提高地震资料分辨率的一个有效途径就是衰减补偿,通过对地震波的衰减和频散效应进行校正,提高地震资料的分辨率。常规衰减补偿方法都是基于波场延拓的反Q滤波方法。本文利用Futterman衰减模型,导出了一种衰减介质中合成地震记录的计算方法,在此基础上将衰减补偿问题归结为一个Fredholm积分方程反问题,利用反演方法来实现衰减补偿。针对衰减补偿问题的不稳定性,利用Tikhonov正则化方法提高反演过程的稳定性,数值模拟资料和实际资料处理结果验证了方法的有效性。  相似文献   
104.
地震资料处理中相对保幅性讨论   总被引:1,自引:0,他引:1  
芮拥军 《物探与化探》2011,35(3):371-374
地震资料的相对保幅性处理是进行岩性油气藏勘探的基础,目前关于相对保幅性处理业界没有统一的认识,缺乏对关键处理技术的系统分析.笔者根据多年的实际地震资料处理经验,重点分析了相对保幅处理的难点,提出相对保幅处理的几项判断标准,并以此标准对振幅处理、噪声压制和提高分辨率等处理技术的保幅性进行了分析,这对相对保幅处理具有一定的...  相似文献   
105.
中国的生态补偿实施主要通过制度安排进行。在内蒙古农牧交错带,生态补偿主要通过两种模式进行,即对农牧户放弃土地使用和生产结构调整给予补偿。基于详尽的野外调查,本研究对农牧户经济受偿意愿进行了对比分析,并对两种生态补偿模式的效应进行了详细评价。结果表明,放弃土地使用的生态补偿模式缺乏创造就业机会的机制,因此不具有可持续性。与此相反,调整生产结构的补偿方式不但使农户从事农牧业的规模有了明显下降,而且有助于创造更多的就业机会。虽然这种模式会使农户面临很大的市场风险,但是它为解决区域生态系统恢复和社会经济发展之间的矛盾提供了一种有效方法。  相似文献   
106.
王莉  贺兆成  刘彩云 《山东地质》2011,(8):61-63,66
为切实维护失地农民的合法权益,日照市不断加快征地补偿安置制度改革的步伐,积极探索失地农民的保护性就业政策措施,努力拓展失地农民安置渠道,逐步建立起失地农民的社会保障制度,为失地农民安居乐业以及维护社会长治久安提供了有力保障。  相似文献   
107.
We have compiled carbonate chemistry and sedimentary CaCO3% data for the deep-waters (>1500 m water depth) of the southwest (SW) Pacific region. The complex topography in the SW Pacific influences the deep-water circulation and affects the carbonate ion concentration ([CO32−]), and the associated calcite saturation horizon (CSH, where ??calcite=1). The Tasman Basin and the southeast (SE) New Zealand region have the deepest CSH at ∼3100 m, primarily influenced by middle and lower Circumpolar Deep Waters (m or lCPDW), while to the northeast of New Zealand the CSH is ∼2800 m, due to the corrosive influence of the old North Pacific deep waters (NPDW) on the upper CPDW (uCPDW). The carbonate compensation depth (CCD; defined by a sedimentary CaCO3 content of <20%), also varies between the basins in the SW Pacific. The CCD is ∼4600 m to the SE New Zealand, but only ∼4000 m to the NE New Zealand. The CaCO3 content of the sediment, however, can be influenced by a number of different factors other than dissolution; therefore, we suggest using the water chemistry to estimate the CCD. The depth difference between the CSH and CCD (??ZCSH−CCD), however, varies considerably in this region and globally. The global ??ZCSH−CCD appears to expand with increase in age of the deep-water, resulting from a shoaling of the CSH. In contrast the depth of the chemical lysocline (??calcite=0.8) is less variable globally and is relatively similar, or close, to the CCD determined from the sedimentary CaCO3%. Geochemical definitions of the CCD, however, cannot be used to determine changes in the paleo-CCD. For the given range of factors that influence the sedimentary CaCO3%, an independent dissolution proxy, such as the foraminifera fragmentation % (>40%=foraminiferal lysocline) is required to define a depth where significant CaCO3 dissolution has occurred back through time. The current foraminiferal lysocline for the SW Pacific region ranges from 3100-3500 m, which is predictably just slightly deeper than the CSH. This compilation of sediment and water chemistry data provides a CaCO3 dataset for the present SW Pacific for comparison with glacial/interglacial CaCO3 variations in deep-water sediment cores, and to monitor future changes in [CO32−] and dissolution of sedimentary CaCO3 resulting from increasing anthropogenic CO2.  相似文献   
108.
黄海暖流的路径及机制研究   总被引:9,自引:1,他引:8  
赵胜  于非  刁新源  司广成 《海洋科学》2011,35(11):73-80
利用NASA/AVHRR 反演的每日海表面温度资料, 法国航天局AVISO 发布的海表面高度资料,中国气象科学数据共享服务网成山头台站的日均风场资料, 首先对黄海海表面温度分布进行了分析,揭示了表征黄海暖流的暖水舌存在两个分支。然后对1981 年10 月~2010 年5 月这两个分支发生情况进行了统计, 得出两个分支并...  相似文献   
109.
研究了在连续的X波段导航雷达图像序列中丢失一帧图像状态下的一种快速修复算法.该算法主要采用基于运动估计与运动补偿的视频序列修复技术进行插帧修复.具体步骤是根据雷达图像中像素点的运动特点,采用改进的三步搜索算法并结合双向运动估计进行搜索,然后对矢量场进行后续处理,最后内插出重建帧.为了提高图像修复的精度,还引入了亚像素运...  相似文献   
110.
复杂地区典型特征往往表现为近地表地质结构复杂,纵向、横向变化大,地下地质构造破碎,大倾角老地层出露。作者介绍了该类地区地震资料的主要特点;分析了处理好该类地震资料起决定性作用的静校正、去噪技术、频率补偿及偏移成像几个重要环节,并指出了生产中应注意的几个问题。  相似文献   
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