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Thermocline has a significant impact on marine fishery, navy submarine activity, ocean circulation and internal wave. In consideration of long range, low cost, and high maneuverability, the AUV (Autonomous Underwater Vehicle) is an ideal platform for ocean local precisely thermocline tracking. Combining with the advantage of the AUV yo-yo movement, this paper presents a simple and effective thermocline...
Temperature has a notable effect on sound speed and attenuation of sediment both in theoretical analysis and in laboratorial measurement. The speed of sediment is positively correlated with temperature universally, but the relationship between attenuation and temperature may be more complicated. In the paper, based on the analysis of influence of permeability, frequency, and other physical parameters...
Towed multiple-parameter profiling system, which is used to measure temperature, depth, turbidity, dissolved oxygen, pH, chlorophyll and other elements of the marine environment, is an important observation equipment to provide information on the marine environment. Based on the test for CZT1-2 towed multiple-parameter profiling system carried out in August 2011 in the Bohai Sea, we have studied the...
Conductivity, temperature and depth (CTD) are the most essential physical properties of sea water. CTD instrument is one of the most efficient approaches for collecting the accurate ocean information. However, traditional CTD instruments are not best suited for applications that require high resolution data by a large number of sensors because of their large size and high cost. This paper describes...
Turbulence plays a crucial role in ocean dynamics and global biogeochemical cycles through redistributing heat, salt and nutrients across isodensity surfaces. Conventionally, most of microstructure measurements were conducted with vertical freefall profilers. In order to provide both a very high resolution vertical distribution of turbulent quantities and the long term series, a novel instrument MRVP...
As the continuous accumulation of knowledge for the Ocean, it is universally acknowledged that there is an evergrowing awareness of the vital importance of the ocean in whatever aspects. Temperature and conductivity, as basic hydrological parameters of the Ocean, play extremely important roles in marine resource recognition, exploitation and utilization. The paper designs a underwater inductive coupling...
In this study, we used an improved and more complex productmeter than previously designed for research and education. We performed daytime measurements on photosynthesis of Ulva pertusa on equipment to support one day, in order to examine its potential use as a teaching tool in university (higher education) programs to study environmental maintenance, reproduction, and creation along coastal areas...
Gliders are the state-of-the-art autonomous underwater vehicles (AUV) that can operate unattended for roughly a month-long period in the ocean. Given a forward horizontal speed of 0.25 ms−1, gliders can cover ∼ 25 km per day. They trace sawtooth profiles in the ocean by changing buoyancy, observing subsurface temperature, conductivity, and other water properties versus depth, and at the surface, fix...
Scouring is the major component of levee failures causing floods thus make the scour monitoring very important. There exist some on field mechanisms to monitor the health of the levees but there is still need for a remote, low cost and real time monitoring system. This paper proposes a real time structural monitoring system by presenting a sensor node with embedded electronics which can be deployed...
According to the principle of electric-magnetic-electric transformation relations, the underwater intelligent wireless inductive charging system based on principle of electromagnetic induction, which achieves the effect of wireless charging is proposed in this paper and it is characterized by safety, simple and agility. The details of system's principle, system's working procedure, hardware circuits...
Japan imports more than 94% of its primary energy supply and the import figures reach up to 250 billon US dollars every year. Imported energy resources in the form of crude oil and natural gas are mainly from Middle East Asia and South Asia. The political instability in these region and crude oil scarcity in the future possess a risk of procurement for the energy demands. Improvement of rate of energy...
An in-situ calibration method to accurately and precisely constrain the pH of deep sea environments is reported. This method involves the pre-evaluation of the Ir-IrOx|Ag-AgCl electrode in the laboratory, followed by the in situ calibration using pH buffers at the ocean bottom. The standard potential E° and in situ slope are derived by the calibration process. This calibration method was implemented...
Methane hydrates are considered as new natural gas resources. For long time commercial gas production, it is needed to increase gas production efficiency. In this study, we carried out hydrate dissociation experiments by depressurization with wellbore heating method for artificial sandy cores. Contribution of wellbore heating was small for hydrate dissociation. This is coursed that the production...
In the modern era of technology Free Space Optics (FSO) communication is a propitious technique for communication among islands or terminals over sea. However, when the beams of laser strikes through the atmosphere, the wavefront of that laser beam opposed by stern influences triggered by the atmospheric turbulence. In this paper, we reassembled the wavefront aberration with Zernike polynomials and...
Automated environmental monitoring in marine environments is currently carried out either by small-scale robotic systems, composed of one or few robots, or static sensor networks. In this paper, we propose the use of swarm robotics systems to carry out marine environmental monitoring missions. In swarm robotics systems, each individual unit is relatively simple and inexpensive. The robots rely on...
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