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The Office of Technology, Planning, and Integration for Observation (TPIO) maintains gap analysis tools that are used to compare both observing system attributes and the National Oceanic and Atmospheric Administration (NOAA) User Observation Requirements to help answer NOAA-wide business questions regarding observational needs and investment. Using the information connected to NOAA products, a capabilities...
An enhanced current meter was deployed in the Antarctic in March, 2017, to measure vertical heat flux in the deep ocean. The purpose of this measurement of flux is to understand how mixing of dense Weddell Sea Bottom Water becomes Antarctic Bottom Water (AABW), the densest water of the Atlantic Ocean outside of trenches. Deep mixing is one of the problems that is not yet well understood despite its...
Predicting the performance of an underwater acoustic network (UAN) is a challenging task due to the spatiotemporal variability of the links and its complicated dependence on multiple factors. We present a machine-learning model based on logistic regression (LogR) to capture the spatio-temporal variation in the performance of a UAN. The model captures the effect of environmental factors such as wind...
Field measurements of turbulence are presented for a proposed current energy converter site near Kuchinoshima Island. The site was selected for its suitability to harness the energy of the Kuroshio Current. The measurements are analyzed focusing on the engineering aspects. Turbulence is known to effect the performance and working life of turbines due to fatigue so its characteristics are important...
Limits of a comparative evaluation of the performance of a conventional X-band marine radar (MR) sigma S6 WaMoS® II used for surface current measurements are dicussed. Main focus of the paper is to address challenges when comparing current measurements from different measuring devices for evaluation purpose. Although the current measurement principles of MRs and acoustic Doppler current profilers...
All commercial fishery species harvested globally either live on or near the seabed (also referred to as the benthos or benthic environment) or employ life history strategies or behaviors linked to benthic processes. The act of pursuing and catching benthic and demersal species requires operating fishing gear on or very near the seabed, resulting in direct gear-seabed contact. It is essential to further...
In this study, turbulent flows were measured using the Expendable Vertical Microstructure Profiler (VMP-X) at the hydrothermal fields in the Okinawa Trough (Iheya North field and Noho site) and Sagami Bay (off Itoh and at Ohmuro Caldera) to characterize the turbulence intensity. For each observation point, the turbulent flow data were successfully measured between the sea surface and the sea floor...
In 2005 the Department of the Interior, through the Minerals Management Service (MMS), issued a Notice to Lessees (NTL No. 2005-G05) requiring collection of ocean current speed and direction profiles in active oil and gas exploration and production sites. The NTL stipulates that ocean current profiles be collected down to 1000 meters (from ∼ 30 meters) at a minimum of 20 minute intervals and be delivered...
Ocean Networks Canada submitted a proposal to Western Economic Diversification Canada (WED) in 2014 to develop ocean monitoring infrastructure using advanced sensing technologies in areas critical to BC's economic future, such as the proposed LNG facilities at Campbell River, and the ports of Kitimat and Prince Rupert. The proposed infrastructure included technology related to monitoring maritime...
The National Oceanic and Atmospheric Administration's Ecosystems and Fisheries Oceanography Coordinated Investigations biophysical mooring site 2 (M2, 56.9°N, 164°W) time series, one of the longest running time series of its kind, has provided near-continuous biophysical measurements of the southeastern Bering Sea shelf since 1995. Since then, the array has evolved into four long-term monitoring sites...
As oceanographic observation instruments of lumped parameter, with more than thirty years employment and development, ADCPs/AWACs have given its advantages and potentials to full play and shown great prospects in wave measurement up to now. This paper collects and uperficially reviews the publications refer to surface wave measurement with ADCP that have been developed since 1970s. Divided into four...
In order to work out the accident caused by the impact or frequent current into the ground on person or equipment near the substation when transmission line tower is short-circuited, the technology of multi-point monitoring to scattered current in the ground were studied in this paper. And then the method is verified by simulation and experiment. At the same time, the scattered current of not monitored...
Given a beginning and ending document, automated storytelling attempts to fill in intermediary documents to form a coherent story. This is a common problem for analysts; they often have two snippets of information and want to find the other pieces that relate them. Evaluation of the quality of the created stories is difficult and has routinely involved human judgment. This work extends the state of...
The world's population has doubled in the past three decades and continues to grow. Intensive farming practices have so far met the increasing demand for food, but they have had a significant, negative environmental impact. Precision agriculture uses technology to increase efficiency and reduce the environmental impacts of farming. A novel sensor concept has been designed for measuring spatial and...
Kalman Filters are utilised for filtering and estimation in a large set of application. Here, this methodology is utilised for trajectory estimation of an underwater robot. In this work, three Kalman Filter methods are proposed for trajectory estimation. There are: Extended Kalman Filter (EKF), Unscented Kalman Filter (UKF) and Central Difference Kalman Filter (CDKF). Simulation results are presented...
This paper presents a real-time, low-cost, wireless, AC and DC monitoring system based on an ATmega328P-PU microcontroller. The proposed system is composed by different client nodes, which have the task to measure the main electrical quantities involved in the system, and a server node that collects the data and send them to a display device. The system is well suited for a good accuracy monitoring...
In this article a sliding mode plus PI controller is proposed to control of the voltage and the input current of a photovoltaic system. The proposed nonlinear controller is designed to control the duty cycle of the two level interleaved boost converter due to changes in the operating conditions of the photovoltaic panel (changes in irradiance levels). Besides this, the proposed controller can operate...
In the given article described principles of modeling of the transformations elements of power sources control. The classical methods of modeling of transformations circuits do not provide necessary accuracy due to complexity of representation of interdependence between input and output quantities and parameters, and the difficulty in representing inter chain and inter chain dependencies and providing...
This paper proposes a voltage reference operating up to 170 °C for low-power high-temperature systems. The proposed circuit buffers body voltages to avoid degradation of temperature coefficient from nwell/psub diode leakage. For low power overhead, it measures the diode leakage and adaptively adjusts the bias current of the buffers. This enables low power consumption at low temperature, which can...
The correct functioning of data measuring systems is impossible without timely metrological examination and calibration of measuring channels. Uncalibrated channels can transmit unreliable data, leading to the poor monitoring and incorrect decision making. The overview of the current research in the field of measuring channels calibration shows the low research activity in this area and highlights...
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