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51.
为提高我国海洋调查船的使用和管理水平,文章根据相关评估报告和统计数据,概述美国UNOLS船队和我国海洋调查船的营运成本情况,分析海洋调查船日均营运成本的计算和应用。研究结果表明:UNOLS船队将海洋调查船按级别管理,同时对研究项目和船舶使用实行独立核算,从而在保障海洋调查任务的前提下有效控制和降低船舶营运成本,值得我国海洋调查船队借鉴;通过计算海洋调查船的日均营运成本,可用于船舶技术经济论证、船舶年度标准可用天数确定和相同级别船舶对比,具有实际应用意义。  相似文献   
52.
The Fram Strait is very important with regard to heat and mass exchange in the Arctic Ocean, and the large quantities of heat carried north by the West Spitsbergen Current (WSC) influence the climate in the Arctic region as a whole. A large volume of water and ice is transported through Fram Strait, with net water transport of 1.7–3.2 Sv southward in the East Greenland Current and a volume ice flux in the range of 0.06–0.11 Sv. The mean annual ice flux is about 866,000 km2 yr−1. The Kongsfjorden–Krossfjorden fjord system on the coast of Spitsbergen, or at the eastern extreme of Fram Strait, is mainly affected by the northbound transport of water in the WSC. Mixing processes on the shelf result in Transformed Atlantic Water in the fjords, and the advection of Atlantic water also carries boreal fauna into the fjords. The phytoplankton production is about 80 g C m−2 yr−1 in Fram Strait, and has been estimated both below and above this for Kongsfjorden. The zooplankton fauna is diverse, but dominated in terms of biomass by calanoid copepods, particularly Calanus glacialis and C. finmarchicus. Other important copepods include C. hyperboreus, Metridia longa and the smaller, more numerous Pseudocalanus (P. minutus and P. acuspes), Microcalanus (M. pusillus and M. pygmaeus) and Oithona similis. The most important species of other taxa appear to be the amphipods Themisto libellula and T. abyssorum, the euphausiids Thysanoessa inermis and T. longicaudata and the chaetognaths Sagitta elegans and Eukrohnia hamata. A comparison between the open ocean of Fram Strait and the restricted fjord system of Kongsfjorden–Krossfjorden can be made within limitations. The same species tend to dominate, but the Fram Strait zooplankton fauna differs by the presence of meso- and bathypelagic copepods. The seasonal and inter-annual variation in zooplankton is described for Kongsfjorden based on the record during July 1996–2002. The ice macrofauna is much less diverse, consisting of a handful of amphipod species and the polar cod. The ice-associated biomass transport of ice-amphipods was calculated, based on the ice area transport, at about 3.55 × 106 ton wet weight per year or about 4.2 × 105 t C yr−1. This represents a large energy input to the Greenland Sea, but also a drain on the core population residing in the multi-year pack ice (MYI) in the Arctic Ocean. A continuous habitat loss of MYI due to climate warming will likely reduce dramatically the sympagic food source. The pelagic and sympagic food web structures were revealed by stable isotopes. The carbon sources of particulate organic matter (POM), being Ice-POM and Pelagic-POM, revealed different isotopic signals in the organisms of the food web, and also provided information about the sympagic–pelagic and pelagic–benthic couplings. The marine food web and energy pathways were further determined by fatty acid trophic markers, which to a large extent supported the stable isotope picture of the marine food web, although some discrepancies were noted, particularly with regard to predator–prey relationships of ctenophores and pteropods.  相似文献   
53.
省级气象计量检定业务自动化系统 (以下简称系统) 是省级气象计量部门的业务应用平台, 以提高其业务管理水平、工作效率和检定质量。系统基于现有省级气象计量标准硬件设备,辅之以自动化智能控制技术,采用B/S和C/S软件开发模式,实现检定业务的数字化、信息化和自动化。该系统包含计量业务管理和自动化检定两个子系统,共用同一个检定数据库。计量业务管理子系统由仪器收发、常规仪器检修、系统管理、预警超检、报表处理、综合查询统计、计量器具管理等模块组成;自动化检定子系统包括温度、湿度、气压、风、雨量等传感器的自动化检测,能够自动采集数据、自动生成原始记录和检测证书。系统的业务应用表明:系统自动化程度高,提高了业务管理水平、工作效率和检定质量。  相似文献   
54.
谢凡  滕云田  胡星星  李琪  徐沁 《地球物理学报》2011,54(10):2698-2707
我国地磁台站观测环境日益受到轨道交通干扰影响,导致地磁观测数据质量下降,制约地磁观测发展.因此,开展干扰抑制的数据处理方法研究,最大限度抑制干扰是提高观测数据质量切实可行的方法.本文提出轨道交通干扰的小波域噪声阈值抑制模型及方法.以天津轨道交通为例,选用受干扰的天津静海地磁台和未受干扰的参考台站河北红山地磁台观测资料,...  相似文献   
55.
中国近海海面高度异常资料再处理   总被引:1,自引:0,他引:1  
卫星海面高度异常产品再处理的研究多集中在欧洲和美国近海,中国近海尚未有过。在产生AVISO(Archiving Validation and Interpolation of Satellite Oceanographic Data)全球0.25°多颗卫星海面高度异常产品时,只用了1/3~1/2的部分沿轨资料,给区域海洋动力学研究造成了一定的限制。本研究尝试利用多颗卫星的所有沿轨资料及25个测潮站的观测资料,通过最优插值方法产生一份新的中国近海海面高度异常资料。新资料的空间分辨率仍为0.25°,但使用了来自3颗卫星(Jason-1、Jason-2、Cryo Sat-2)的所有沿轨资料及25个测潮站的观测资料。新资料的范围为10°S~50°N、90°~160°E。新资料与AVISO资料的对比分析表明新资料更接近沿轨海面高度异常观测,同时也更接近测潮站资料。与AVISO资料相比,新资料与沿轨海面高度异常观测的均方根误差降低了10.03%,与测潮站资料的均方根误差降低了9.6%。  相似文献   
56.
The field of ocean geochemistry has recently been expanded to include in situ laser Raman spectroscopic measurements in the deep ocean. While this technique has proved to be successful for transparent targets, such as fluids and gases, difficulty exists in using deep submergence vehicle manipulators to position and control the very small laser spot with respect to opaque samples of interest, such as many rocks, minerals, bacterial mats, and seafloor gas hydrates. We have developed, tested, and successfully deployed by remotely operated vehicle (ROV) a precision underwater positioner (PUP) which provides the stability and precision movement required to perform spectroscopic measurements using the Deep Ocean Raman In situ Spectrometer (DORISS) instrument on opaque targets in the deep ocean for geochemical research. The positioner is also adaptable to other sensors, such as electrodes, which require precise control and positioning on the seafloor. PUP is capable of translating the DORISS optical head with a precision of 0.1 mm in three dimensions over a range of at least 15 cm, at depths up to 4000 m, and under the normal range of oceanic conditions (T, P, current velocity). The positioner is controlled, and spectra are obtained, in real time via Ethernet by scientists aboard the surface vessel. This capability has allowed us to acquire high quality Raman spectra of targets such as rocks, shells, and gas hydrates on the seafloor, including the ability to scan the laser spot across a rock surface in sub-millimeter increments to identify the constituent mineral grains. These developments have greatly enhanced the ability to obtain in situ Raman spectra on the seafloor from an enormous range of specimens.  相似文献   
57.
Digital terrain modeling has a micro- and nanoscale counterpart in surface metrology, the numerical characterization of industrial surfaces. Instrumentation in semiconductor manufacturing and other high-technology fields can now contour surface irregularities down to the atomic scale. Surface metrology has been revolutionized by its ability to manipulate square-grid height matrices that are analogous to the digital elevation models (DEMs) used in physical geography. Because the shaping of industrial surfaces is a spatial process, the same concepts of analytical cartography that represent ground-surface form in geography evolved independently in metrology. The surface topography of manufactured components, exemplified here by automobile-engine cylinders, is routinely modeled by variogram analysis, relief shading, and most other techniques of parameterization and visualization familiar to geography. This article introduces industrial surface-metrology, examines the field in the context of terrain modeling and geomorphology and notes their similarities and differences, and raises theoretical issues to be addressed in progressing toward a unified practice of surface morphometry.  相似文献   
58.
问卷调查方法在中国人文地理学研究的应用   总被引:5,自引:1,他引:4  
问卷调查方法是人文地理学微观研究的重要工具,在以人为本的城市发展理念影响下开始得到广泛应用。本文运用文献计量方法分析问卷调查方法在中国人文地理学研究的应用概况,同时以2013年北京宜居城市问卷调查为案例,重点阐述问卷调查过程的抽样方案设计思想,最后对问卷调查方法的主要应用领域进行回顾总结,以期促进问卷调查方法在中国人文地理学研究的科学规范应用。研究发现:问卷调查方法在中国人文地理学研究的应用逐渐增强,研究内容不断拓展与深化,研究区域涵盖不同空间尺度、并以微观尺度为趋势,研究方法以数理统计、GIS空间分析等定量方法为主,但对问卷抽样设计阐述却不够科学规范;通过2013年北京宜居城市问卷调查案例分析,强调对问卷收集方法、抽样方式和抽样框选取、样本量确定等内容所构成的抽样方案设计过程重视,以加强问卷调查数据的科学采集;问卷调查方法在时空行为、人居环境、城市社会、旅游行为和农户行为等主题展开大量应用实践,在此基础上对问卷调查方法研究框架进行总结,并提出国内问卷调查方法应用的改进方向。  相似文献   
59.
文章就土工试验仪器设备的计量控制工作中的若干具体问题展开讨论。应以国家计量法为基准,以保证测试成果的准确性能,结合室内土工试验专业特点,做好有关工作。  相似文献   
60.
谷田平 《测绘通报》2019,(5):152-154
基于加油站对卧式金属罐容积内部交接的应用需要,本文采用天宝TX8三维激光扫描仪进行容积测量标定,并与传统的容积比较法及激光点阵法对某加油站20 m3卧式金属罐进行数据比较及建模分析。测试数据表明,天宝TX8在卧式金属罐容积标定方面较激光点阵法符合性更高,建模更加全面、直观、高效,为其在其他测量领域及力学建模方面的拓展应用提供了可能。  相似文献   
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