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1.
深水海洋平台的现场原型监测是对其最直接的研究方法和安全保障措施,是我国深水油气开发研究中的必要技术。为了改变我国缺乏南海半潜式浮体实测经验的现状,为半潜式浮体设计与安全保障提供实测数据支持,在南海LH11-1油田"南海挑战号"半潜式平台上进行了台风期的原型测量工作。原型测量工作采用针对南海浮式平台应用所研发的原型测量系统,对平台工作海域的环境参数、平台姿态以及水下系泊和立管系统进行了监测,获得了跨台风期中大量的实测数据,最终对所获得的数据进行了初步的分析。分析结果显示原型测量系统在海洋平台上使用具有很高的稳定性,捕获了台风期中所有过境平台的台风数据,获得的数据能够为平台性能评价和新平台设计提供第一手资料。  相似文献   

2.
Matched-fieId inversion (MFI) undertakes to estimate the geometric and geoacoustic parameters in an ocean acoustic scenario by matching acoustic field data recorded at hydrophone array with numerical calculations of the field. The model which provides the best fit to the data is the estimate of the actual experimental scenario. MFI provides a comparatively inexpensive method for estimating ocean bottom parameters over an extensive area. The basic components of the inversion process are a sound propagation model and matching (minimization) algorithm. Since a typical MFI problem requires a large number of computationally intensive sound propagation calculations, both of these components have to be efficient. In this study, a hybrid inversion algorithm which uses a parabolic equation propagation model and combines the downhill simplex algorithm with genetic algorithms is introduced. The algorithm is demonstrated on synthetic range-dependent shallow-water data generated using the parabolic equation propagation model. The performance for estimating the model parameters is compared for realistic signal-to-noise ratios in the synthetic data  相似文献   

3.
南大洋气旋气候与变化特征   总被引:2,自引:1,他引:1  
A new climatology of cyclones in the Southern Ocean is generated by applying an automated cyclone detection and tracking algorithm(developed by Hodges at the Reading University) for an improved and relatively highresolution European Centre for Medium-Range Weather Forecasts atmospheric reanalysis during 1979–2013.A validation shows that identified cyclone tracks are in good agreement with a available analyzed cyclone product.The climatological characteristics of the Southern Ocean cyclones are then analyzed,including track,number,density,intensity,deepening rate and explosive events.An analysis shows that the number of cyclones in the Southern Ocean has increased for 1979–2013,but only statistically significant in summer.Coincident with the circumpolar trough,a single high-density band of cyclones is observed in 55°–67°S,and cyclone density has generally increased in north of this band for 1979–2013,except summer.The intensity of up to 70% cyclones in the Southern Ocean is less than 980 h Pa,and only a few cyclones with pressure less than 920 h Pa are detected for1979–2013.Further analysis shows that a high frequency of explosive cyclones is located in the band of 45°–55°S,and the Atlantic Ocean sector has much higher frequent occurrence of the explosive cyclones than that in the Pacific Ocean sector.Additionally,the relationship between cyclone activities in the Southern Ocean and the Southern Annular Mode is discussed.  相似文献   

4.
A pop-up bottom seismic recorder designed for seismic refraction experiments was built by the Institute of Oceanographic Sciences in 1968. The device is housed within a 71 cm diameter sphere weighing 270 kg when launched. signals picked up by a hydrophone are recorded in analogue form on magnetic tape in the band 2–100 Hz. The total continuous recording period is 12 hr but the lifetime of the system can be effectively extended by cycling the tape-recorders to allow shooting to go on for up to 3 days. Ballast release is by acoustic command or by pre-set clock. The instruments have been used in water depths from 150 to 4820 m making a total of 63 deployments with a 95% recovery rate. A new version with three-component geophones is being built.  相似文献   

5.
Divinsky  B. V.  Kuklev  S. B. 《Oceanology》2022,62(2):155-161

The main purpose of the study is an analysis of the wave climate of Novorossiysk Bay (Black Sea) for 1979–2019. The analysis is based on mathematical modeling results obtained with the modern DHI MIKE 21 SW spectral wave model. The wave model was verified using numerous instrumental data of the wind-wave parameters in the Black Sea and Sea of Azov. As follows from the research, the average power of storm waves in Novorossiysk Bay area is about 8 kW/m. The maximum power ranges from 50 to 100 kW/m but can reach 200 kW/m or more. The total duration of storm waves for one year is 40–60 days. The maximum duration of one storm can be up to three days but does not exceed two days on average. The mean storm duration is usually 10–11 h. The largest number of storms (above 130) was recorded in 2004; on average, there are about 100 storms annually. In recent decades, in the area of Novorossiysk Bay, the maximum wind-wave heights and the total number of storms has increased with statistical control. It is also highly probable that the average annual power of combined waves and maximum storm duration have increased; i.e., the time of continuous wave impact has increased.

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6.
The Hawaii Institute of Geophysics began development of the Ocean Subbottom Seisometer (OSS) system in 1978, and OSS systems were installed in four locations between 1979 and 1982. The OSS system is a permanent, deep ocean borehole seismic recording system composed of a borehole sensor package (tool), an electromechanical cable, recorder package, and recovery system. Installed near the bottom of a borehole (drilled by the D/V Glomar Challenger), the tool contains three orthogonal, 4.5-Hz geophones, two orthogonal tilt meters; and a temperature sensor. Signals from these sensors are multiplexed, digitized (with a floating point technique), and telemetered through approximately 10 km of electromechanical cable to a recorder package located near the ocean bottom. Electrical power for the tool is supplied from the recorder package. The digital seismic signals are demultiplexed, converted back to analog form, processed through an automatic gain control (AGC) circuit, and recorded along with a time code on magnetic tape cassettes in the recorder package. Data may be recorded continuously for up to two months in the self-contained recorder package. Data may also be recorded in real time (digital formal) during the installation and subsequent recorder package servicing. The recorder package is connected to a submerged recovery buoy by a length of bouyant polypropylene rope. The anchor on the recovery buoy is released by activating either of the acoustical command releases. The polypropylene rope may also be seized with a grappling hook to effect recovery. The recorder package may be repeatedly serviced as long as the tool remains functionalA wide range of data has been recovered from the OSS system. Recovered analog records include signals from natural seismic sources such as earthquakes (teleseismic and local), man-made seismic sources such as refraction seismic shooting (explosives and air cannons), and nuclear tests. Lengthy continuous recording has permitted analysis of wideband noise levels, and the slowly varying parameters, temperature and tilt.Hawaii Institute of Geophysics Contribution 1909.  相似文献   

7.
Lepidocybium flavobrunneum (Smith, 1849) is widespread in warmer oceanic waters and has recently been recorded in the catches of tuna longline vessels in the New Zealand region. Twenty‐five specimens were caught at 31°46′‐32°03′S, 170°49′‐171°11′ E on 23–27 June 1979, thus extending the known range of the species to northern New Zealand.  相似文献   

8.
In this paper, we describe an underwater electronic holographic camera (eHoloCam) that has been developed for in situ studies of the distribution and dynamics of plankton and other marine organisms and particles. The eHoloCam uses an Nd-YAG pulsed laser to freeze-frame fast moving particles and a complementary metal-oxide-semiconductor (CMOS) sensor for high-resolution image capture. Digital holograms and holographic videos are recorded at rates from 5 to 25 Hz over a period of several hours. Data is stored locally on an embedded computer. The eHoloCam is capable of recording all organisms and particles located in a water volume of 36.8 cm3 in a single hologram frame. The recorded holographic videos may subsequently be reconstructed numerically at a desired image plane. The main optical and mechanical specifications for eHoloCam are also described. To record electronic holographic videos of marine organisms, the eHoloCam was deployed from a towed sampling frame [autorecording instrumented environmental sampler (ARIES)] on the research vessel RV Scotia at speeds up to 4 kn (about 2 mldrs-1) in the North Sea off the Shetland Isles. Various images of marine organisms obtained from this deployment are shown, together with preliminary measurements on the distribution of Calanus copepods.  相似文献   

9.
A simple construction of the MSL-110 sediment trap developed at the Laboratory of Physical-Geological Research of the Shirshov Institute of Oceanology, Russian Academy of Sciences, is presented. The trap is easily assembled from standard parts available at stores. The trap is easy to use, reliable, and inexpensive. It is applied for determination of sedimentary matter fluxes and their components in water columns of seas, lakes, and other water reservoirs.  相似文献   

10.
东海大陆架区海胆分类研究   总被引:1,自引:0,他引:1  
海胆是重要的大型海洋底栖生物类群之一,某些海胆既是人工养殖对象,又是捕捞对象。因此,对海胆进行分类研究,摸清其地理分布特点,对合理利用海胆资源以及生物多样性研究都可提供基本科学依据。 对我国海胆的分类学研究始于1948年,当时张凤瀛先生对青岛的6种海胆进行了描述(张凤瀛,1948)。1957年张凤瀛和吴宝铃先生对广东沿海的37种海胆进行了研究(张凤瀛等,1957)。张凤瀛先生等1964年在《中国动物图谱,棘皮动物门》中记录了30种我国常见海胆(张凤瀛等,1964)。廖玉麟先生在20世纪70年代对西沙群岛的棘皮动物进行了分类研究,其中包括26种海胆(廖玉麟,1978)。 中国科学院海洋研究所于1958-1982年在东海大陆架进行过多次的综合性海洋调查。调查范围:26°~33°45′N,122°~129°E。该海域的底栖生物种类繁多,多样性丰度高。本文对中国科学院海洋研究所历年采自东海大陆架的海胆进行了较系统的研究,共包括21种,隶属于7目、11科、17属。其中有11种在我国是首次记录。名录如下,有*者为新记录。  相似文献   

11.
12.
An ocean bottom seismometer array on the Nova Scotia shelf edge recorded T-phases from an earthquake swarm on the mid-Atlantic ridge at about 31.6° N in June 1975. The swarm occured along a segment of the ridge that ruptured similarly 17 yr previously. From 1964 to mid-1979 the worldwide network recorded three other earthquake swarms along this segment of the mid-Atlantic ridge (MAR). A sparse network of sensors in the SOFAR channel, having a lower magnitude threshold, might provide a better means of monitoring the seismicity of both short-length transforms and ridge crests along the MAR than does the worldwide seismic network.  相似文献   

13.
This paper describes a method to identify the parameters of the dynamic model of a fixed offshore platform subjected to wind-generated random waves using its stationary response. The structure is modeled as a single degree of freedom system. The parameters identified are the damping coefficient, the natural frequency, and the excitation. In addition, the moment and force acting on the foundation are also identified. The method uses the random decrement signature as a tool to identify the parameters in the equation of motion. Excellent agreements were obtained between the predicted and actual values of the parameters as well as for the reaction and moment at the platform's foundation. The method can be applied without any interruption to the operation of the offshore structure. The method is easy to apply, and uses inexpensive motion measurement instruments. The estimated force and moment can be used as a tool for an on-line foundation check.  相似文献   

14.
The reproduction of dynamic processes in the stratosphere at extratropical latitudes is considered in calculations of the atmospheric module of the global climate model of the Institute of Numerical Mathematics, Russian Academy of Sciences, with an upper boundary of 0.2 hPa (~60 km) for the period from 1979 to 2008 in comparison with the data observational. Changes in temperature, zonal wind, activity of planetary waves, heat fluxes in the lower stratosphere, and sudden stratospheric warmings with the displacement and splitting of the polar vortex, as well as the distribution of associated circulation anomalies in the troposphere, are analyzed.  相似文献   

15.
This paper presents a review of the results from Russian studies of the middle atmosphere in 2007–2010 drawn up by the Commission on the Middle Atmosphere of the Section of Meteorology and Atmospheric Sciences of the National Geophysical Committee, Russian Academy of Sciences, for the National Report on Meteorology and Atmospheric Sciences submitted to the XXIV General Assembly of the International Union of Geodesy and Geophysics (Melbourne, Australia, June 28–July 7, 2011).  相似文献   

16.
An analysis is given of the methods of operational oceanography based on measurements derived from satellite data, observations acquired by drifters and passing vessels, and modern simulations of marine and oceanic circulations. In addition, a historical review is conducted of the previous and current research in this field carried out in the Soviet Union, Ukraine, and Russia. A discussion is given of the principles underlying the design of an effective data-computing system (DCS) for solving the problems of operational oceanography and the implementation of the prototype system for the Black Sea within the joint research project of the Russian Academy of Sciences (RAS) and the National Academy of Sciences of Ukraine (NASU) “The Black Sea as an Ocean Simulation Model.” The effectiveness of applying the multicomponent splitting method in the construction of sea circulation models and specialized DCSs with integrated algorithms of variational assimilation of observational data is estimated. The concept of using the Black Sea as a testing site for innovations is developed. The underlying idea of the concept is the similarity of the Black Sea dynamics with processes in the oceans. The numerical Black Sea circulation models used in the project are described, their development areas are discussed, and the requirements to a Black Sea observing system are defined.  相似文献   

17.
The Energy Harvesting Eel (Eel) is a new device that uses piezoelectric polymers to convert the mechanical flow energy, available in oceans and rivers, to electrical power. Eel generators make use of the regular trail of traveling vortices behind a bluff body to strain the piezoelectric elements; the resulting undulating motion resembles that of a natural eel swimming. Internal batteries are used to store the surplus energy generated by the Eel for later use by a small, unattended sensor or robot. Because of the properties of commercially available piezoelectric polymers, Eels will be relatively inexpensive and are easily scaleable in size and have the capacity to generate from milli-watts to many watts depending on system size and flow velocity of the local environment. A practical Eel structure has been developed that uses the commercially available piezoelectric polymer, PVDF. Future Eels may use more efficient electrostrictive polymer. Every aspect of the system from the interactions between the hydrodynamics of the water flow and structural elements of the Eel, through the mechanical energy input to the piezoelectric material, and finally the electric power output delivered through an optimized resonant circuit has been modeled and tested. The complete Eel system, complete with a generation and storage system, has been demonstrated in a wave tank. Future work on the Eel will focus on developing and then deploying a small, lightweight, one-watt power generation unit, initially in an estuary and then subsequently in the ocean. Such Eels will have the ability to recharge batteries or capacitors of a distributed robotic group, or remote sensor array, thus extending the mission life indefinitely in regions containing flowing water  相似文献   

18.
Large oscillations of water level in Nagasaki Bay are calledAbiki and are most frequently observed in winter. The largestAbiki recorded in the past 20 years at the tide station at Nagasaki occurred on March 31, 1979. Simultaneously, a distinct atmospheric pressure disturbance of solitary type with an amplitude of about 3 mb was recorded at several neighbouring stations in Kyûshû, which indicated the pressure disturbance probably travelled eastward with an average speed of about 110 km h–1.The quantitative relation between this pressure disturbance and notable seiches observed in Nagasaki Bay is examined by means of numerical simulation, and it is confirmed that the exceptionally large range of oscillations in the bay, which reached 278 cm at the tide station, was indeed produced by this travelling pressure disturbance.The leading part of shallow water waves induced by the atmospheric pressure disturbance was amplified up to about 10 cm in amplitude, over the broad continental shelf region off China, because of near resonant coupling to the pressure disturbance. After leaving this continental shelf region, the amplified water wave converged into the shelf region (Gotô Nada) surrounded by the north-western coast of Kyûshû and the Gotô Islands and excited eigenoscillations on the shelf. A train of waves thus formed with a period of about 35 min entered Nagasaki Bay and was resonantly amplified at periods of 36 min and 23 min which are the eigen periods of the bay. Besides resonance, the combined effects of shoaling and reflection inside Nagasaki Bay also enhanced the amplification.  相似文献   

19.
ThedistributionofChaetognathainthewesterncentralPacific¥DaiYanyu(1.ThirdinstituteofOceanography,StateOceanicAdministration,Xi...  相似文献   

20.
《Oceanologica Acta》1999,22(6):651-661
The relationship between hard substrate type, depth and ecology has not been widely investigated in Bass Strait, which separates mainland Australia from Tasmania. As this water body is important to the State, a study along the Victorian coastline using an inexpensive Along Track Video (ATV) system, along with equipment to record depths and locations, was implemented. A better understanding of the correlation between hard substrate, depth and ecology was thought to be valuable to enable researchers to determine to what extent the benthic biological communities depend on physical factors. This understanding should improve procedures to predict the seafloor ecology on the basis of geological and oceanographic data. The dominant species assemblages and geomorphology, among other characteristics, were observed and recorded for each transect. In the sites investigated, depth appears to have a greater influence on dominant assemblages than does the type of hard substrate. The study also served to show that inexpensive ATV systems can be successfully used to study macro-sessile marine resources.  相似文献   

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