scholarly journals Data Management, Infrastructure and Archiving for Time-Domain Astronomy

2011 ◽  
Vol 7 (S285) ◽  
pp. 249-254
Author(s):  
David Schade
Keyword(s):  
Data Management ◽  
Time Domain ◽  
Network Performance ◽  
Large Data ◽  
Significant Degree ◽  
Careful Consideration ◽  
Data Intensive ◽  
Data Preservation ◽  
Long Time ◽  
The Time Domain

AbstractThe workshop on Data Management issues for Time-Domain Astronomy was conceived as a forward-looking discussion of the primary issues that need to be addressed for science in the time domain. The very broad diversity of the science areas presented in the main Symposium made it clear that most of the general issues for astronomy data management—for example, large data volumes, the need for timely processing and network performance—would be pertinent in the time domain. In addition, there might be other tight time constraints on data processing when the output was required to trigger rapid follow-up observations, while science based on very long time-baselines might require careful consideration of long-term data preservation and availability issues. But broadly speaking, data management challenges in the time domain are not at variance to any significant degree with those for astronomy or data-intensive research in general. The workshop framed and debated a number of questions: What is the biggest challenge faced by future projects? How do grid and cloud computing figure in data management plans? Is the Virtual Observatory important to future projects? How are the issues of data life cycle being addressed?

Estimating interannual variability arising from weather events

2001 ◽  
Vol 38 (A) ◽  
pp. 274-288 ◽  
Author(s):  
Xiaogu Zheng ◽  
James Renwick
Keyword(s):  
Frequency Domain ◽  
Interannual Variability ◽  
Time Domain ◽  
Synthetic Data ◽  
Estimation Procedure ◽  
Frequency Domain Method ◽  
Domain Method ◽  
Weather Events ◽  
Long Time ◽  
The Time Domain

The advantages and limitations of frequency domain and time domain methods for estimating the interannual variability arising from day-to-day weather events are summarized. A modification of the time domain method is developed and its application in examining a precondition for the frequency domain method is demonstrated. A combined estimation procedure is proposed: it takes advantage of the strengths of both methods. The estimation procedures are tested with sets of synthetic data and are applied to long time series of three meteorological parameters. The impacts of the different methods on tests of potential long-range predictability for seasonal means are also discussed.

Time Domain Fatigue Life Analysis of Offshore Jacket Structure

2019 ◽  
Author(s):  
Yan Wei Wu
Keyword(s):  
Fatigue Life ◽  
Fatigue Damage ◽  
Time Domain ◽  
Offshore Wind ◽  
Support Structure ◽  
Structural Fatigue ◽  
Long Time ◽  
Fatigue Life Analysis ◽  
Stress Concentration Factors ◽  
The Time Domain

Abstract Offshore wind system encountered wind, wave, current, soil, and other environmental loads. The support structure is randomly loaded for a long time, which is more likely to cause fatigue damage. In this paper, the NREL 5MW wind turbine and OC4 jacket support structure is selected to perform the time domain fatigue analysis. Commercial software Bladed and SACS are used to perform the required structural responses and fatigue strength calculations. The Stress Concentration Factors (SCF) and S-N curves for the stress calculations of tubular joints are adopted based on the recommendation of DNV GL guidelines. The magnitude of the stress variation range and the corresponding number of counts are obtained by using the rain-flow counting algorithm. Finally, the Palmgren-Miner’s rule is adopted to calculate the cumulative damage ratio and the fatigue life can then be estimated. Fatigue damage ratio and structural fatigue life of each joint during 20 years of operation period are evaluated.

scholarly journals Categorization and Characterization of Time Domain CMOS Temperature Sensors

Sensors ◽  
2020 ◽  
Vol 20 (22) ◽  
pp. 6700
Author(s):  
Sangjin Byun
Keyword(s):  
Time Domain ◽  
Supply Voltage ◽  
Complementary Metal Oxide Semiconductor ◽  
Temperature Sensors ◽  
Oxide Semiconductor ◽  
Voltage Sensitivity ◽  
Power Supply Voltage ◽  
Measured Time ◽  
Long Time ◽  
The Time Domain

Time domain complementary metal-oxide-semiconductor (CMOS) temperature sensors estimate the temperature of a sensory device by measuring the frequency, period and/or delay time instead of the voltage and/or current signals that have been traditionally measured for a long time. In this paper, the time domain CMOS temperature sensors are categorized into twelve types by using the temperature estimation function which is newly defined as the ratio of two measured time domain signals. The categorized time domain CMOS temperature sensors, which have been published in literature, show different characteristics respectively in terms of temperature conversion rate, die area, process variation compensation, temperature error, power supply voltage sensitivity and so on. Based on their characteristics, we can choose the most appropriate one from twelve types to satisfy a given specification.

Aerodynamic Analysis of the Helicopter Rotor Using the Time-Domain Panel Method

2009 ◽  
Author(s):  
Seawook Lee ◽  
Leesang Cho ◽  
Hyunmin Choi ◽  
Jinsoo Cho
Keyword(s):  
Time Domain ◽  
Numerical Technique ◽  
Aerodynamic Characteristics ◽  
Panel Method ◽  
Helicopter Rotor ◽  
Aerodynamic Analysis ◽  
Aerodynamic Performances ◽  
Long Time ◽  
Wake Model ◽  
The Time Domain

Recently, aerodynamic analysis of the helicopter rotor using computational fluid dynamics (CFD) is widely carried out with high accuracy. But, it is very long time to calculate aerodynamic performances and it is difficult to simulate the wake shape of the helicopter rotor using CFD analysis. In this research the time-domain panel method, which uses a numerical technique based on the piecewise constant source and doublet singularities, is applied to the analysis and prediction of the unsteady aerodynamic characteristics of helicopter rotor in a potential flow. And the free wake model is used for wake simulation. The results of present method are compared with the results of experiment of a helicopter rotor in hover and in forward flight. Results show good agreement with the experimental results.

scholarly journals Evolving Persistent Archives and Digital Library Systems: Integrating iRods, Cheshire3 and Multivalent

2013 ◽  
Vol 8 (2) ◽  
pp. 47-67 ◽  
Author(s):  
Reagan Moore ◽  
Arcot Rajasekar ◽  
Paul Watry ◽  
Fabio Corubolo ◽  
John Harrison ◽  
...  
Keyword(s):  
Data Management ◽  
Digital Library ◽  
Academic Research ◽  
The United States ◽  
Distributed Data ◽  
Data Intensive ◽  
Data Preservation ◽  
Wide Range ◽  
Data Collections ◽  
The University

This paper describes work undertaken by Data Intensive Cyber Environments Center (DICE) at the University of North Carolina at Chapel Hill and the University of Liverpool on the development of an integrated preservation environment, which has been presented at the National Coordination Office for Networking and Information Technology Research and Development (NITRD), at the National Science Foundation, and at the European Commission. The underlying technology is based on the integrated Rule-Oriented Data System (iRODS), which implements a policy-based approach to distributed data management. By differentiating between different phases of the data life cycle based upon the evolution of data management policies, the infrastructure can be tuned to support data publication, data sharing, data analysis and data preservation. It is possible to build generic data management infrastructure that can evolve to meet the management requirements of each user community, federal agency and academic research project. In order to manage the properties of the data collections, we have developed and integrated scalable digital library services that support the discovery of, and access to, material organized as a collection.The integrated preservation environment prototype implements specific technologies that are capable of managing a wide range of preservation requirements, from parsing of legacy document formats, to enforcement of preservation policies, to validation of trustworthiness assessment criteria. Each capability has been demonstrated and is instantiated in multiple instances, both in the United States as part of the DataNet Federation Consortium (DFC) and through multiple European projects, primarily the FP7 SHAMAN project.

Estimating interannual variability arising from weather events

2001 ◽  
Vol 38 (A) ◽  
pp. 274-288
Author(s):  
Xiaogu Zheng ◽  
James Renwick
Keyword(s):  
Frequency Domain ◽  
Interannual Variability ◽  
Time Domain ◽  
Synthetic Data ◽  
Estimation Procedure ◽  
Frequency Domain Method ◽  
Domain Method ◽  
Weather Events ◽  
Long Time ◽  
The Time Domain

The advantages and limitations of frequency domain and time domain methods for estimating the interannual variability arising from day-to-day weather events are summarized. A modification of the time domain method is developed and its application in examining a precondition for the frequency domain method is demonstrated. A combined estimation procedure is proposed: it takes advantage of the strengths of both methods. The estimation procedures are tested with sets of synthetic data and are applied to long time series of three meteorological parameters. The impacts of the different methods on tests of potential long-range predictability for seasonal means are also discussed.

Apodisation in the time domain

1992 ◽  
Vol 2 (4) ◽  
pp. 615-620
Author(s):  
G. W. Series
Keyword(s):  
Time Domain ◽  
The Time Domain

Risk Management on Information Security in ABC Company

2017 ◽  
Vol 4 (1) ◽  
pp. 62-66
Author(s):  
Luyen Ha Nam
Keyword(s):  
Risk Management ◽  
Information Security ◽  
Data Management ◽  
Management System ◽  
Risk Mitigation ◽  
Data Management System ◽  
Data Centre ◽  
Long Time ◽  
Mitigation Action ◽  
Better Than

From long, long time ago until nowadays information still takes a serious position for all aspect of life, fromindividual to organization. In ABC company information is somewhat very sensitive, very important. But how wekeep our information safe, well we have many ways to do that: in hard drive, removable disc etc. with otherorganizations they even have data centre to save their information. The objective of information security is to keep information safe from unwanted access. We applied Risk Mitigation Action framework on our data management system and after several months we have a result far better than before we use it: information more secure, quickly detect incidents, improve internal and external collaboration etc.

JOINT INTERPRETATION OF AIRBORNE ELECTROMAGNETIC DATA IN THE TIME DOMAIN AND FREQUENCY DOMAIN

2018 ◽  
Vol 12 (7-8) ◽  
pp. 76-83
Author(s):  
E. V. KARSHAKOV ◽  
J. MOILANEN
Keyword(s):  
Fourier Transform ◽  
Frequency Domain ◽  
Time Domain ◽  
Frequency Interval ◽  
Single Spectrum ◽  
Simultaneous Inversion ◽  
Homogeneous Half Space ◽  
Time Domain Data ◽  
The Time Domain

Тhe advantage of combine processing of frequency domain and time domain data provided by the EQUATOR system is discussed. The heliborne complex has a towed transmitter, and, raised above it on the same cable a towed receiver. The excitation signal contains both pulsed and harmonic components. In fact, there are two independent transmitters operate in the system: one of them is a normal pulsed domain transmitter, with a half-sinusoidal pulse and a small "cut" on the falling edge, and the other one is a classical frequency domain transmitter at several specially selected frequencies. The received signal is first processed to a direct Fourier transform with high Q-factor detection at all significant frequencies. After that, in the spectral region, operations of converting the spectra of two sounding signals to a single spectrum of an ideal transmitter are performed. Than we do an inverse Fourier transform and return to the time domain. The detection of spectral components is done at a frequency band of several Hz, the receiver has the ability to perfectly suppress all sorts of extra-band noise. The detection bandwidth is several dozen times less the frequency interval between the harmonics, it turns out thatto achieve the same measurement quality of ground response without using out-of-band suppression you need several dozen times higher moment of airborne transmitting system. The data obtained from the model of a homogeneous half-space, a two-layered model, and a model of a horizontally layered medium is considered. A time-domain data makes it easier to detect a conductor in a relative insulator at greater depths. The data in the frequency domain gives more detailed information about subsurface. These conclusions are illustrated by the example of processing the survey data of the Republic of Rwanda in 2017. The simultaneous inversion of data in frequency domain and time domain can significantly improve the quality of interpretation.

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