双机热备份测量系统的设计与实现

在实时测量系统中，系统软硬件的可靠性是系统设计的重要部分。介绍了某型综合调查船测量控制系统的热备份软硬件系统的设计与实现，采用网络技术、心跳监测和数据库技术，实现了系统的故障检测、实时报警和自动切换，保证了不间断的高质量数据采集和测量系统的可靠运行。     

油轮“鱼尾”运动及Hopf分叉算法

本文使用一个六阶三自由度的非线性数学模型，研究单点系泊（ＳＰＭ）系统“鱼尾”运动，对系统的平衡状态，及其在风向角、风速、流速、缆绳长度等参数变化时规律，进行了一系列的分析，同时，指出了静平衡系泊力的变化规律。为了研究系统平衡态的稳定性，文中选择缆绳长度ｌ为分叉参数，分析了在不同参数值下，系统Ｊａｃｏｂｉａｎ矩阵的各组特征值的变化情况，并求出了系统的Ｈｏｐｆ分叉点。最后，本文利用Ｈｏｐｆ分叉理论，求出了系统的Ｈｏｐｆ分叉周期解。     

一种实时水下声图象的获取,处理和自动识别系统

本文介绍了一种实时水下声图象的获取、处理和自动识别系统，对构成系统的软，硬件系统作了概要的描述，并给出相应的框图和部分实验结果，本系统曾成功地用于松花江沉船的找捞任务，证明已达到实用阶段。     

无线监测,监控系统的设计方法

在城市的交通、电力、供热、自来水、煤气等行业中，无线监测、监控系统是解决这些待业有关生产自动调度、环境监测与监控的最佳方案之一。本文通过对天津市热网监测系统的介绍，论述了采用超短波无线通信技术实现热网监测、监控系统的方法及系统组成结构，从而为同类系统的开发提供一般设计方法。     

伽利略系统及其地面段的设计

伽利略(Galileo)系统是欧洲的全球卫星导航服务(GNSS)系统，依据有关Galileo系统建设的最新资料，比较系统地介绍了Galileo系统的定义、提供的服务、联合执行体的组织运作模式和SAR服务等，详细地介绍了系统地面段的设计状况和某些问题。     

智能温湿测量仪表的语音系统

设计智能气象测量仪表的语音系统，该系统可用语音实时报出气象参数的测量结果，还可报警。该系统以听觉的形式扩大了智能气象仪表的应用范围，使工作效率大为提高，信息掌握更加灵活、方便。另外，该系统与微机接口简单，连接方便，编程简单，适用于以单片机为核心的智能测量仪表等系统采用。     

南沙海域断裂系统对含油气盆地的控制

南沙海域断裂构造十分发育，其中长度超过20km的断裂达150条。在断裂系统划分时，由于不同学者着眼点和侧重点不同，对断裂系统的划分有一定的差别。龚铭等根据断裂的展布规律和形态划分出四大断裂系统：NE向断裂系统，NW向断裂系统，SN向断裂系统和南缘弧形断裂系统。宋海斌等利用重磁场和地震资料对南海断裂进行了识别，并根据断裂展布方向划分出北西向断裂组、北东向断裂组、南北向断裂组和东西向断裂组。     

船载式远程高精度水声定位系统

本文比较了各种水声定位跟踪系统的特点，由此可明显看出长基线模式的船载式水声定位跟踪系统将兼有使用方便、适用性强、定位精度高、作用距离远的优点，仔细分析了要实现这类系统的关键技术难题，介绍了我国自行研制的一个船载式远程高精度水声定位系统的组成和工作原理，该系统还率先突破了主动式水声定位系统中非模糊距离Ｒｍａｘ＝ＣＴ的原理性限制，使系统可进行远程，高数据率跟踪定位     

深海大型资料浮标的设计与试验研究

本文在全面分析已有资料的基础上，提出深海大型资料浮标锚碇系统的形式选择、系统布置和各部件设计方法。考虑了锚系防鲨咬的问题；分析了系统受力情况，建立了系统受力分析的数学模型，编制系统静力计算程序。     

长江水上110系统中空间数据库的设计

基于长江水上110系统的开发实践，阐述了系统中空间数据库的设计过程，具体论述了该空间数据库的特点、数据的组织、分类、编码及数据库内容，总结了此类系统空间数据库建设的经验。     

Microbial Biomass and Organic Nutrients in the Deep-Sea Sediments of the Central Indian Ocean Basin

In order to assess the impact of deep-sea mining on the in situ benthic life, we measured the microbial standing stock and concentration of organic nutrients in the deep-sea sediments of the Central Indian Ocean Basin in the Indian pioneer area. Sediments were collected using box core and grab samples during September 1996. The total bacterial numbers ranged from 10 10 -10 11 cells per g -1 dry weight sediment. There was a marginal decrease in the number of bacteria from surface to 30 cm depth, though the subsurface section registered a higher number than did the surface. The highest numbers were encountered at depths of 4-8 cm. The retrievable number of bacteria were two orders less in comparison with the direct total counts of bacteria. An almost homogeneous distribution of bacteria, total organic carbon, living biomass, and lipids throughout the depth of cores indicates active microbial and benthic processes in the deep sea sediments. On the other hand, a uniform distribution of total counts of bacteria, carbohydrates, and total organic carbon in all the cores indicates their stable nature and suggests that they can serve as useful parameters for long-term monitoring of the area after the benthic disturbance. Further studies on temporal variability in this region would not only verify the observed norms of distribution of these variables but would also help to understand restabilization processes after the simulated benthic disturbance.     

海上大直径钢管桩打桩过程中桩周土强度弱化研究

海上大直径钢管桩打桩过程中,桩周土体受到强烈扰动而发生强度弱化,掌握桩周土体强度弱化规律对于准确预测打桩过程、保证工程安全具有重要意义。为研究土体强度弱化规律,开展了环剪试验模拟打桩对桩周土体的扰动,测试土体强度随剪切速率的变化规律,建立了描述土体强度弱化规律的拟合公式,引入到打桩分析软件中。研究结果表明：土体的强度折减程度不仅与土体本身的性质有关还受到土体的埋深和剪切速率的影响,埋深越深土体强度折减程度越低,剪切速率越高土体强度折减越高,在打桩分析中可采用这里推荐的线性折减方法来模拟不同深度处土体强度的折减规律。     

Geoacoustic Inversion via Genetic Algorithm and Its Application to Manganese Sediment Identification

An acoustic inversion method using a wide-band signal and two near field receivers is proposed and applied to multiple layered seabed models including a manganese sediment. The inversion problem can be formulated into a probabilistic model comprised of signals, a forward model, and additive noise. The forward model simulates wide-band signals, such as chirp signals, and is chosen to be the source-waveletconvolution plane wave modeling method. The wavelet matching technique, using weighted least-squares fitting, estimates the sediment sound-speed and thickness on which determination of the possible numerical ranges for a priori uniform distribution is based. The genetic algorithm is applied to a global optimization problem to find a maximum a posteriori solution for determined a priori search space. Here the object function is defined by an L 2 norm of the difference between measured and modeled signals. Not only the marginal pdf but also its statistics are calculated by numerical evaluation of integrals using the samples selected during importance sampling process of the genetic algorithm.     

A Review of Some Environmental Issues Affecting Marine Mining

This article reviews information recently available from existing marine and coastal mining for responses to environmental issues affecting marine mining at different depths. It is particularly but not exclusively concerned with those issues affecting seabed biodiversity impact and recovery. Much information has been gathered in the past 10 years from shallow mining operations for construction aggregate, diamonds, and gold, from coastal mines discharging tailings to shallow and deep water, and from experimental deep mining tests. The responses to issues identified are summarized in a series of eight tables intended to facilitate site-specific consideration. Since impacts can spread widely in the surface mixing layer SML, and can affect the biologically productive euphotic zone, the main issues considered arise from the depth of mining relative to the SML of the sea. Where mining is below the SML, the issue is whether it is environmentally better to bring the extraction products to the surface vessel for processing (and waste discharge), or to process the extraction products as much as possible on the seabed. Responses to the issues need to be sitespecific, and dependent on adequate preoperational environmental impact and recovery prediction. For deep tailings disposal from a surface vessel, there are four important environmental unknowns: (1) the possible growth of "marine snow" (bacterial flocs) utilizing the enormous quantities of fine tailings particles (hundreds or thousands of metric tons per day) as nuclei for growth, (2) the possibility that local keystone plankton and nekton species may migrate diurnally down to and beyond the depth of deep discharge and hence be subjected to tailings impact at depth, (3) the burrow-up capability of deep benthos and their ability to survive high rates of tailings deposition, and (4) the pattern and rate of dispersion of a tailings density current through the deep water column from discharge point to seabed. Actions to obtain relevant information in general and site-specifically are suggested.     

Increased Particle Fluxes at the INDEX Site Attributable to Simulated Benthic Disturbance

Particle fluxes were measured 7 m above the sea bottom during the predisturbance, disturbance, and postdisturbance periods by using time series sediment traps attached to seven deep-sea moorings deployed in the INDEX experiment site in the Central Indian Basin. The predisturbance particle fluxes varied between 22.3 to 55.1 mg m -2 day -1 . Increased and variable particle fluxes were recorded by the sediment traps during the disturbance period. The increase observed was 0.5 to 4 times more than the background predisturbance fluxes. The increases in particle fluxes (~4 times) recorded by the sediment trap located in the southwestern direction (DMS-1) were the greatest, which could be the result of preferential movement of resuspended particles generated during the deep-sea benthic disturbance along the general current direction prevailing in this area during the experimental period. Also, the traps located closer to the disturbance area recorded greater fluxes than did the traps far away, across the Deep Sea Sediment Resuspension System path. This variability in recorded particle fluxes by the traps around the disturbance area clearly indicates that physical characteristics such as grain size and density of the resuspended particles produced during the disturbance had an important effect on particle movement. The postdisturbance measurements during ~5 days showed a reduction in particle fluxes of ~50%, indicating rapid particle settlement.     

Phylogenetic diversity and phenotypic characterization of cultivable bacterioplankton isolated from polar oceans

A set of 27 marine planktonic bacteria isolated from the polar regions was characterized by 16S rDNA sequencing and physiological and biochemical testing. More than half of these bacteria were positive for caseinase, gelatinase and 13-glucosidase, and could utilize glucose, maltose or malic acid as carbon source for cell growth. Twelve isolates expressed nitrate reduction activities. Except for one antarctic isolate BSwlO175 belonging to Actinobacteria phylum, these isolates were classified as γ-Proteobacteria, suggesting that γ-Proteobacteria dominated in cultivable marine bacterioplankton at both poles. Genus Pseudoalteromonas was the predominant group in the Chukchi Sea and the Bering Sea, and genus ShewaneUa dominated in cultivable bacterioplankton in the Prydz Bay. With sequence similarities above 97%, genus Psychrobacter was found at both poles. These 27 isolates were psychrotolerant, and significant 16S rDNA sequence similarities were found not only between arctic and antarctic marine bacteria （ 〉 99% ）, but also between polar marine bacteria and bacteria from other aquatic environments （ ≥ 98.8% ）, including temperate ocean, deep sea, pond and lake, suggesting that in the polar oceans less temperature-sensitive bacteria may be cosmopolitan and have a bipolar, even global, distribution at the species level.     

Determination of In Situ Sediment Shear Strength from Advanced Piston Corer Pullout Forces

The advanced piston corer (APC) has been used by the Ocean Drilling Program since 1985 for recovering soft sediments from the ocean floor. The pullout force measured on extracting the core barrel from the sediment is shown to correlate with the average shear strength of the sediment core measured in the ship's laboratory. A simple rule of thumb is derived relating the shear strength of the sediment to the pullout force. Multiple APC holes at individual sites allow the consistency of the pullout measurements to be assessed. The effects of different operational procedures during APC coring are also explored. Although generally applicable, the correlation between pullout force and laboratory measurements of shear strength breaks down for some APC holes, possibly because of the disturbance of some sediment types during the APC coring process. A better understanding of the physical process of APC coring, and its effect on the properties of the sediment both inside and immediately outside the core barrel, would indicate what confidence can be put on the measurement of pullout force as a way of evaluating the in situ shear strength of deep sea sediments.     

Deep-Sea Sediment Compression Curves: Some Controlling Factors, Spurious Overconsolidation, Predictions, and Geophysical Reproduction

Oedometer tests have been carried out on 70 undisturbed surficial clays (at approximately 250 mm below the mudline), mostly collected by free-fall corers from sites widely scattered throughout the deep-sea North Atlantic. Acoustic measurements were also made, initially on contiguous samples and ultimately on the same sample using a geophysically instrumented oedometer which also collected electrical resistivity data. Apart from those quiescent areas below the carbonate compensation depth, such as north of the West Indies where very fine clays exist, most of the samples are silty clays whose geotechnical-geophysical properties are dependent on the type of clay minerals present (and their ability to take in moisture), the sand-size fraction, and the quantity of carbonate present. Thus the pure clays have high compressibilities which decrease on the addition of coarse particles, while the converse is true for the acoustic parameters, these increasing with the sand fraction. Using the notion of the intrinsic compression line for all samples, and comparison to it of the measured compression curves, it is clear that, contrary to some previously held ideas, most deep-sea clays are normally consolidated; the addition of carbonate has the effect of creating an open, stronger sediment skeleton. Interestingly, where information is available, the variation with depth of a sample's acoustic velocity follows the void ratio pressure relationship of the compression curve. This allows the construction of an in-situ sediment compression curve using the in-situ geophysical observations.