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1.
基于海洋环境安全保障、海洋环境预报和海洋科学研究的需要,开展国产深海准实时传输潜标系统的设计,重点进行锚泊系统水动力分析、观测设备工作同步性、准实时通讯系统安全可靠和系统低功耗等整体技术设计;开展轻型感应耦合传输缆制作、大深度感应耦合传输和智能收放通讯等数据实时通讯技术的研究;进行适用于准实时传输潜标系统的多种类国产设备的稳定性和可靠性优化、规模化集成和系统化的应用示范,形成半潜升降式准实时通讯潜标与浮子式准实时通讯潜标各1套。所设计的准实时传输潜标系统集成了1台抗污染CTD、19台感应耦合CTD、8台感应耦合T、4台感应耦合传输的ADCP、2台单点海流计和6台感应耦合数据传输仪,并配有2套声学释放器;潜标系统本体设计含有3个水下流线型浮体、1套通讯浮子、1套准实时卫星通讯装置(半潜式水下绞车或海面浮子)和1套锚泊缆系,可实现深达2000mm的剖面温盐深和海流等海洋要素的高频率、多要素、多层次的长期连续观测和数据准实时传输,以便对科学问题解决和海洋环境安全保障等提供及时的数据支撑。  相似文献   

2.
The sedimentary infill of the Bay of Biscay off Ireland, UK, France and Spain took place in four phases. The last one (35 Ma to present) is characterised by gravitational, pelagic, contouritic and glacigenic processes leading to the setup of three deep sea systems. To the North, the Celtic and Armorican fans are fed by a “canyon-dominated” margin and its connection with the “Manche” palaeoriver, which drained a large area of western Europe. To the South, the Cap-Ferret fan results from the evolution of a “tectonic-dominated” margin and the erosion of the Pyrenee mountains.  相似文献   

3.
Our understanding of the significance of sound production to the ecology of deep-sea fish communities has improved little since anatomical surveys in the 1950s first suggested that sound production is widespread among slope-water fishes. The recent implementation of cabled ocean observatory networks around the world that include passive acoustic recording instruments provides scientists an opportunity to search for evidence of deep-sea fish sounds. We examined deep-sea acoustic recordings made at the NEPTUNE Canada Barkley Canyon Axis Pod (985 m) located off the west coast of Vancouver Island in the Northeast Pacific between June 2010 and May 2011 to determine the presence of fish sounds. A subset of over 300 5-min files was examined by selecting one day each month and analyzing one file for each hour over the 24 h day. Despite the frequent occurrence of marine mammal sounds, no examples of fish sounds were identified. However, we report examples of isolated unknown sounds that might be produced by fish, invertebrates, or more likely marine mammals. This finding is in direct contrast to recent smaller studies in the Atlantic where potential fish sounds appear to be more common. A review of the literature indicates 32 species found off British Columbia that potentially produce sound could occur in depths greater than 700 m but of these only Anoplopoma fimbria and Coryphaenoides spp. have been previously reported at the site. The lack of fish sounds observed here may be directly related to the low diversity and abundance of fishes present at the Barkley Canyon site. Other contributing factors include possible masking of low amplitude biological signals by self-generated noise from the platform instrumentation and ship noise. We suggest that examination of data both from noise-reduced ocean observatories around the world and from dedicated instrument surveys designed to search for deep-sea fish sounds to provide a larger-scale, more conclusive investigation into the role, or potential lack thereof, of sound production.  相似文献   

4.
王蓓  陈永华  于非 《海洋科学》2021,45(7):81-94
论文结合中国科学院海洋研究所2017年至2018年在西太平洋布放的一套6000m深自容式锚泊潜标系统,利用其温、深、盐及海流数据,参考卫星观测的海面资料,依据潜标结构组成,创新性地选用多体动力学软件ADAMS建立柔性缆体有限元模型,进行复原式姿态模拟,对此潜标异常沉降情况进行原因探究,提出减小因潜标大深度沉降导致影响的方法。本文所提出的柔性体模型,可依据海流参数变化改变有限元长度,自定义流阻状态,已被证明在较小海流和海流异常大两种分布模型的拟下,计算机有限元模型分析所得绝对沉降误差达缆绳总长0.18%和0.41%。通过计算机模型依据实际情况的模拟结果,最终印证异常沉降值的形成原因:(1)在系泊结构既定且安全布放的前提下,其沉降异常值的出现只能与其当日所处环境的海流分布状态相关。模型锚泊最大受力8621N,合理选择布放地点、潜标材料可降低系泊损坏风险;(2)若大洋中尺度涡形成和临近导致流速激增,其对整个系统的作用将决定锚系系统布放期间异常沉降深度,由于中尺度涡的形成与迁移具有可预报性,结合系泊深度和位置的及时调整可减小超深度沉降所导致的影响。  相似文献   

5.
深海自主/遥控式水下机器人(ARV)作为新兴的复合型水下机器人,融合了自主式水下机器人的灵活性和遥控式水下机器人的人机交互性等优势,开启了自主与遥控混合作业的新模式。深海ARV可切换为AUV自主航行模式,独立采集周边区域近海底地形地貌、地质结构以及环境参数等数据,也能下潜至目标区域后切换为ROV遥控模式进行局部观察和采样操作,其探测作业一体化技术代表了具备复杂使命执行力的第三代深海水下机器人的发展方向。通过分析国内外深海混合型水下机器人的发展现状,结合ARV在中国深海矿产资源调查中的主要应用案例和取得的成果,以6000米级 “问海一号”ARV系统的研发为例,给出其关键技术集成以及面对的技术挑战,并对未来深海ARV的应用场景、功能集成和发展方向提出了一些设想和建议。  相似文献   

6.
环肋圆柱壳是深海无人系统广泛采用的一种耐压结构形式,保障其结构安全是系统研制过程中非常重要的一环。针对环肋圆柱壳的结构特征推导了组合结构重量关系式和结构参数简化估算方法,并以一种超长型深海无人系统耐压结构为例,围绕大长径比环肋圆柱壳的结构形式、设计计算、仿真分析、模型验证等开展研究。研究表明提出的大长径比环肋圆柱壳结构设计参数简化估算方法具有较好的适应性。相关计算和分析结果可以为该型深海无人系统结构设计提供技术支撑,也可以为其他类似耐压结构设计提供参考。  相似文献   

7.
自治水下机器人在深海采矿系统湖试中的应用   总被引:1,自引:1,他引:0  
以大洋采矿前期的湖试为例,介绍了AUV在矿产资源调查和深海采矿中的应用。在深海采矿系统作业前期,利用AUV调查湖底的地形地貌、结核的分布与覆盖率,确定集矿机作业地点的大地坐标。在深海采矿系统作业后期,利用AUV调查集矿机在湖底的行走轨迹和压陷深度,估算回采率。  相似文献   

8.
Sustainability of deep-sea fisheries   总被引:1,自引:0,他引:1  
As coastal fisheries around the world have collapsed, industrial fishing has spread seaward and deeper in pursuit of the last economically attractive concentrations of fishable biomass. For a seafood-hungry world depending on the oceans' ecosystem services, it is crucial to know whether deep-sea fisheries can be sustainable.The deep sea is by far the largest but least productive part of the oceans, although in very limited places fish biomass can be very high. Most deep-sea fishes have life histories giving them far less population resilience/productivity than shallow-water fishes, and could be fished sustainably only at very low catch rates if population resilience were the sole consideration. But like old-growth trees and great whales, their biomass makes them tempting targets while their low productivity creates strong economic incentive to liquidate their populations rather than exploiting them sustainably (Clark's Law). Many deep-sea fisheries use bottom trawls, which often have high impacts on nontarget fishes (e.g., sharks) and invertebrates (e.g., corals), and can often proceed only because they receive massive government subsidies. The combination of very low target population productivity, nonselective fishing gear, economics that favor population liquidation and a very weak regulatory regime makes deep-sea fisheries unsustainable with very few exceptions. Rather, deep-sea fisheries more closely resemble mining operations that serially eliminate fishable populations and move on.Instead of mining fish from the least-suitable places on Earth, an ecologically and economically preferable strategy would be rebuilding and sustainably fishing resilient populations in the most suitable places, namely shallower and more productive marine ecosystems that are closer to markets.  相似文献   

9.
The traction capacity of the mining machine is greatly in?uenced by the traction rheological properties of the deep-sea sediments. The best simulative soil was prepared for substituting the deep-sea sediment based on the deep-sea sediment collected from the Paci?c C-C mining area. Traction rheological properties of the simulative soil were studied by a home-made test apparatus. In order to accurately describe the traction rheological properties and determine traction rheological parameters, the Newtonian dashpot in Maxwell body of Burgers model was replaced by a self-similarity spring-dashpot fractance and a new rheological constitutive model was deduced by fractional derivative theory. The results show the simulative soil has obvious non-attenuate rheological properties. The transient creep and stable creep rate increase with the traction, but they decrease with ground pressure. The fractional derivative Burgers model are better in describing non-attenuate rheological properties of the simulative soil than the classical Burgers model. For the new traction rheological constitutive equation of the simulative soil, the traction rheological parameters can be obtained by ?tting the tested traction creep data with the traction creep constitutive equation. The ground contact length of track and walking velocity of the mining machine predicted by the traction rheological constitutive equation can be used to take full advantages of the maximum traction provided by the soil and safely improve mining effciency.  相似文献   

10.
《Marine Policy》2002,26(2):103-106
Interest in deep-sea mining developed in the early 1970s, with a focus on manganese nodules in international waters. Mining may actually occur first, however, on rich polymetallic sulfide deposits associated with hydrothermal vents within exclusive economic zones. Even though mining for polymetallic sulfides may not take place for several years, precautionary performance standards, environmental regulations, and the establishment of Marine Protected Areas may help guide the marine mining industry toward a goal of minimizing environmental impacts. Once substantial investments in prospecting and exploring a potential mining site are made, implementation of environmental regulations may prove to be much more difficult.  相似文献   

11.
Factors such as non-uniform illumination of seafloor photographs and partial burial of polymetallic nodules and crusts under sediments have prevented the development of a fully automatic system for evaluating the distribution characteristics of these minerals, necessitating the involvement of a user input. A method has been developed whereby spectral signatures of different features are identified using a software ‘trained’ by a user, and the images are digitized for coverage estimation of nodules and crusts. Analysis of >20,000 seafloor photographs was carried out along five camera transects covering a total distance of 450 km at 5,100–5,300 m water depth in the Central Indian Ocean. The good positive correlation (R2 > 0.98) recorded between visual and computed estimates shows that both methods of estimation are highly reliable. The digitally computed estimates were ∼10% higher than the visual estimates of the same photographs; the latter have a conservative operator error, implying that computed estimates would more accurately predict a relatively high resource potential. The fact that nodules were present in grab samples from some locations where photographs had nil nodule coverage emphasises that nodules may not always be exposed on the seafloor and that buried nodules will also have to be accounted for during resource evaluation. When coupled with accurate positioning/depth data and grab sampling, photographic estimates can provide detailed information on the spatial distribution of mineral deposits, the associated substrates, and the topographic features that control their occurrences. Such information is critical for resource modelling, the selection of mine sites, the designing of mining systems and the planning of mining operations.  相似文献   

12.
Stable isotope analysis of fish tissue can aid studies of deep-sea food webs because sampling difficulties severely limit sample sizes of fish for traditional diet studies. The carbon stable isotope ratio (δ13C) is widely used in food web studies, but it must be corrected to remove variability associated with varying lipid content in the tissue. A lipid correction has not been determined for any deep-sea fish. These fishes are ideal for studying lipid correction because lipid content varies widely among species. Our objective was to evaluate an application of a mass balance δ13C correction to a taxonomically diverse group of deep-sea fishes by determining the effect of lipid extraction on the stable isotope ratios, examining the quality of the model parameters derived for the mass balance correction, and comparing the correction to published results. We measured the lipid extraction effect on the nitrogen stable isotope ratio (δ15N) and δ13C of muscle tissue from 30 North Atlantic species. Lipid extraction significantly increased tissue δ15N (+0.66‰) and δ13C values, but the treatment effect on δ13C was dependent on C:N, a proxy for lipid content. We compared the lipid-extracted δ13C to the δ13C predicted by the mass balance correction using model variables estimated from either all individuals (pooled) or species-by-species or using published values from other species. The correction using the species-by-species approach performed best; however, all three approaches produced corrected values that were generally within 0.5‰ of the measured lipid-free δ13C and that had a small over-all bias (<0.5‰). We conclude that a generalized mass balance correction works well for correcting δ13C in deep-sea fishes, is similar to that developed for other fishes, and recommend caution when applying a generalized correction to fish with high lipid content (C:N >8).  相似文献   

13.
Haluk Erol   《Ocean Engineering》2005,32(1):37-55
The present study addresses essentially to the investigation of the longitudinal vibrations of a stepped-pipe string for mining from deep-sea floors. The stepped-pipe string, consisting of four parts having different physical properties in each pipe string segment, is assumed to have two pump modules and a buffer, each of which is equipped with a vibration absorber. Moreover, the pipe string is subjected to external viscous damping because of the surrounding medium. A theoretical analysis has been made for a simplified model of the system, in which it is assumed that both the pump modules and buffer can be considered as concentrated masses, the fluid inside of the pipe string vibrates together with the string, and that the flexible pipe does not affect the vibration of the pipe string. Furthermore, absorbers are modeled as concentrated masses, each of which is attached to pump modules and the buffer by springs and dampers. Applying the method of separation of variables, exact analytical solutions for damped free and forced responses of the system subjected to heave motion of the mining ship are determined with and without absorbers, in which overdamped and underdamped modes are determined and studied separately too. It is important to note that the solutions obtained are expressed in terms of parameters characterizing the physical properties of the system under consideration. Numerical applications show that the attachment of convenient vibration absorbers causes the longitudinal displacements at the certain locations to decrease to very small values, where the vibration absorbers are adjusted to the excitation frequency.  相似文献   

14.
针对海底地形不平坦特性,提出了一种变幅机构来自适应海底地形采矿姿态的采矿机构。综合考虑采矿机构采掘头距海底高度对采矿率影响,利用关键点法建立了节臂上的点到海底地形距离的数学模型。在此基础上,建立了以采矿率最高为目标的最优采矿姿态数学模型。以某实际地形为例,采用模拟退火遗传算法优化求解最优采矿姿态。根据其优化后结果可知,其最优采矿姿态与海底地形坡度变化一致,从而证明了采矿姿态模型的正确性。  相似文献   

15.
游志勇  汤熙翔  肖湘 《台湾海峡》2007,26(4):555-561
通过自行改进的高压培养罐及高压设备,对深海沉积物进行可培养微生物的筛选,获得6株具有较强耐受压力的细菌.16SrDNA的测序结果表明这些细菌分别属于6个不同的菌属.压力生长试验的结果表明这6株细菌在40MPa的条件下仍然具有较强的生长能力,属于兼性嗜压菌.对不同压力下生长的细菌做显微镜检,结果显示,除了一株芽孢杆菌在40MPa下的菌体形态发生了明显的变化外,其它5株细菌在压力条件下的菌体的分裂均没有受到明显的影响.  相似文献   

16.
针对深海立管在理想环境和外部水环境中发生碰撞的情况,从立管碰撞最大径向位移和应力峰值两方面展开研究,充分利用ABAQUS仿真得到的数据,基于数值模拟和回归分析,提出四因素三水平的立管碰撞响应面分析方法。采用Design-Expert软件的BOX设计,对立管的非线性碰撞过程中的碰撞应力峰值和最大径向位移等两个试验指标进行回归分析并分别建立二次响应面回归模型。通过将响应面分析所得最优化解与有限元计算结果的对比,最终验证了响应面分析方法及所得模型的准确性。  相似文献   

17.
Five manganese nodules collected from the Northern Mid - Pacific have been analysed for their U and Th isotopes.lt is found that the enrichment of thorium compared to uranium is universal in deep- sea manganese, nodules and in the top sides of the nodules there are large excesses of Th and Pa decreasing exponentially with depth. For each of the nodules, the concordant growth rates are obtained from three different methods: 230Thex 230Thex/232Th and 231Paex.The growth rates of manganese nodules are closely related to the chemical compositions of the nodules and the types of the underlying sediments. The growth rates of five nodules are determined to be in the range of 0.79-7.4 mm/106a, in agreement with those predicted from the chemical compositions of the nodules. By the comparison of the extrapolated 230Thex,230Thex/232 Th and 231PaeX data from the top and bottom surfaces of the nodule from Site M21 yields, the nodule turnover time is (9.83-13.7)×104a.  相似文献   

18.
The mechanism of enhanced diffusivity occurring in the deep-sea perpetual salt fountain has been investigated experimentally and numerically. Some factors which possibly contribute to the enhanced diffusivity were found to be the pipe oscillation with ocean waves and its baffled wall surface. Field experiments in the ocean (Onagawa Bay of Miyagi, Japan) and numerical simulations were performed to study and confirm the dynamics of the flow and heat transport with enhanced diffusivity occurring in upwelling deep-sea water. The agreement between the field experimental data and the numerical solutions of an oscillating-wall boundary condition imposed on the baffled pipe is encouraging, and it indicates the baffled pipe surface subject to the oscillatory motion leads to the enhanced diffusivity. The buoyancy force and then upwelling velocity can be greatly increased by the enhanced diffusivity. The dominant mechanism is the occurrence of complicated vortices and vortex shedding leading to efficient mixing and enhanced diffusion.  相似文献   

19.
深海微生物培养模拟平台温度控制技术研究   总被引:3,自引:0,他引:3  
针对深海微生物培养系统对温度条件的苛刻要求,在分析系统构成及建模的基础上,介绍了一种对系统的两级滞后环节采用了PI控制和双Smith预估反馈的方法,通过内环和外环Smith预估控制,精确的消除了温度控制系统中滞后延迟环节的影响,提高了PI控制强度,减少了超调,提高了系统动态响应和稳态精度。在系统Matlab仿真和实际实验中得到了良好的效果,满足系统的精度要求。  相似文献   

20.
声学法深海热液速度场测量重建算法研究   总被引:1,自引:1,他引:0       下载免费PDF全文
介绍了利用声学法测量深海热液速度场的基本原理.利用往返飞渡时间差与流场速度的关系,应用反问题求解技术重建测量区域的速度场.应用最小二乘法对两种典型的热液口速度场模型进行了仿真重建,分析了换能器数量、实验测量误差以及换能器的布放对重建结果的影响,并对重建结果进行了流量分析.仿真重建的绝对误差、相对误差以及流量分析结果表明...  相似文献   

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