scholarly journals Sensitivity of Altimeter Wave Height Assessment to Data Selection

2020 ◽  
Vol 12 (16) ◽  
pp. 2608 ◽  
Author(s):  
Graham D. Quartly ◽  
Andrey A. Kurekin
Keyword(s):  
Wave Height ◽  
Waveform Inversion ◽  
Open Ocean ◽  
Sea State ◽  
Strong Change ◽  
Good Consistency ◽  
Minimum Number ◽  
New Algorithms ◽  
Selection Of

This paper addresses the issue of how the selection of buoys and the calculation of altimeter averages affect the metrics characterising the errors of altimetric wave height estimates. The use of a 51-point median reduces the sensitivity to occasional outliers, but the quality of this measure can be improved by demanding that there is a minimum number of valid measurements. This had a marked impact in both the open ocean and the coastal zone. It also affected the relative ordering of algorithms’ performances, as some fared poorly when a representative value was gleaned from a single waveform inversion, but had a much better ranking when a minimum of 20 values were used. Validation procedures could also be improved by choosing altimeter-buoy pairings that showed a good consistency. This paper demonstrated an innovative procedure using the median of the different retrackers analysed, which can be easily extended to other data validation exercises. This led to improved comparison statistics for all algorithms in the open ocean, with many showing errors less than 0.2 m, but there was only one strong change in the relative performance of the 11 Jason-3 retrackers. For Sentinel-3A, removing the inconsistent coastal buoys showed that all of the new algorithms had similar errors of just over 0.2 m. Thus, although improvements were found in the procedure used for the Sea State Round Robin exercise, the relative rankings for the buoy calibrations are mostly unaffected.

scholarly journals New Algorithm and Processor for Obtaining Maritime Information from Sentinel-1 Radar Imagery for Near Real Time Services

2020 ◽  
Author(s):  
Andrey Pleskachevsky ◽  
Björn Tings ◽  
Sven Jacobsen ◽  
Egbert Schwarz ◽  
Detmar Krause ◽  
...  
Keyword(s):  
High Resolution ◽  
Synthetic Aperture Radar ◽  
Real Time ◽  
Wave Height ◽  
Surface Wind ◽  
Open Ocean ◽  
Synthetic Aperture ◽  
Sea State ◽  
Sar Imagery

<p>The focus of the study is analysing storm peak/center propagation, front movement and arrival of swell using newest remote sensing information, numerical models, <em>in-situ</em> measurements and their combination. For this purposes, a new empirical algorithm for sea state retrieval from satellite borne Sentinel-1 (S1) Synthetic Aperture Radar (SAR) imagery was developed. The algorithm is applied inside a new processor for meteo-marine parameter estimation for Near Real Time (NRT) applications. These NRT-applications include the investigation of geophysical processes using different satellite modes ranging from high resolution modes with small image coverage of ~20km in open ocean to low resolution modes with wide coverage of ~250km in shelf areas.</p><p>The quick developments in satellite techniques, processors, algorithms and ground infrastructures provide new possibilities for series of oceanographic applications in the last years. These new techniques allow estimation of a wide range of oceanographic information including properties of surface waves and internal waves, surface wind speed, sub-meso scale fronts and eddies, ice coverage, oil spills, coastal bathymetry, currents and others. Generally, the new high resolution products from different models allow verification of meteo-marine parameters more accurately. Here, a cross validation with different sea state model results using WWIII (NOAA) and CMEMS (COPERNICUS), with <em>in situ</em> buoy measurements and with satellite estimated parameters allowed an significant improvement of the accuracy of the derived sea state and wind fields. </p><p>The new empirical algorithm allows estimation of total integrated sea state parameters including significant wave height <em>H<sub>s</sub></em>, first moment wave period <em>T<sub>m1</sub></em>, second moment period <em>T<sub>m2</sub></em>, mean period <em>T<sub>m</sub></em> and also partial integrated parameters like swell and windsea wave heights and windsea period. The algorithm allows processing of different S1 Synthetic Aperture Radar (SAR) modes into sea state fields: </p><ul><li>S1 Wave Mode (WV) acquires multiple vignettes with an extent of ~20km×20km and each displaced by 100 km along satellite tracks in open ocean (global). About 60 tracks around the globe have been acquired per day. The relatively high spatial resolution of ~4 m allows estimating wave height with accuracy of ~35cm. This is comparable with the accuracy of satellite altimetry and a new achievement for SAR based techniques. </li> <li>S1 Interferometric Wide Swath Mode (IW) covers area-strips of thousand kilometres of earth and ocean surface in coastal areas with a resolution of ~30m by sequences of multiple images with an approximate size of 200km×250km. The accuracy of ~ 70cm (<em>H<sub>s</sub></em>) for this mode is not as so high as for S1-WV, because the short waves are not visible for S1-IW mode and imaged as noise. However, the accuracy is much higher than state-of-the-art methods for this mode. </li> </ul><p>The algorithm has been integrated into a prototype processor for Sentinel-1 SAR imagery. The DLR Ground Station Neustrelitz applies this prototype as part of a near real-time demonstrator MSA service. The presented scientific service involves daily provision of surface wind and sea state parameters estimated fully automatically from S1 IW images of North and Baltic Sea in and around German territorial waters.</p>

ON THE EXPERT’S RIGHT TO BE PRESENT AT LEGAL PROCEEDINGS

2016 ◽  
Vol 15 ◽  
pp. 163-171
Author(s):  
M. G. Shcherbakovskiy
Keyword(s):  
Initial Data ◽  
Legal Proceedings ◽  
Reliable Assessment ◽  
Data Acquiring ◽  
Selection Of

The article discusses the reasonsfor an expert to participate in legal proceedings. The gnoseological reason for that consists of the bad quality of materials subject to examination that renders the examination either completely impossible or compromises objective, reasoned and reliable assessment of the findings. The procedural reason consists ofa proscription for an expert to collect evidence himself or herself. The author investigates into the ways of how an expert can participate in legal proceedings. If the defense invites an expert to participate in the proceedings, then it is recommended that his or her involvement should be in the presence of attesting witnesses and recorded in the protocol. In the course of the legal proceedings an expert has the following tasks: adding initial data, acquiring new initial data, understanding the situation of the incident, acquiring new objects to be studied, including samples for examination. An expert’s participation in legal proceedings differs from the participation of a specialist or an examination on the scene of the incident. The author describes the tasks that an expert solves in the course of legal proceedings, the peculiarities ofan investigation experiment practices, the selection of samples for an examination, inspection, interrogation.

Implementasi Voip Server Berbasis IPV6 Dengan Raspberry PI

2019 ◽  
Vol 9 (01) ◽  
pp. 47-54
Author(s):  
Rabbai San Arif ◽  
Yuli Fitrisia ◽  
Agus Urip Ari Wibowo
Keyword(s):  
Internet Protocol ◽  
Wireless Transmission ◽  
Raspberry Pi ◽  
Test Results ◽  
Average Delay ◽  
Ipv6 Network ◽  
Ip Network ◽  
Selection Of ◽  
Better Than

Voice over Internet Protocol (VoIP) is a telecommunications technology that is able to pass the communication service in Internet Protocol networks so as to allow communicating between users in an IP network. However VoIP technology still has weakness in the Quality of Service (QoS). VOPI weaknesses is affected by the selection of the physical servers used. In this research, VoIP is configured on Linux operating system with Asterisk as VoIP application server and integrated on a Raspberry Pi by using wired and wireless network as the transmission medium. Because of depletion of IPv4 capacity that can be used on the network, it needs to be applied to VoIP system using the IPv6 network protocol with supports devices. The test results by using a wired transmission medium that has obtained are the average delay is 117.851 ms, jitter is 5.796 ms, packet loss is 0.38%, throughput is 962.861 kbps, 8.33% of CPU usage and 59.33% of memory usage. The analysis shows that the wired transmission media is better than the wireless transmission media and wireless-wired.

DESIGN, SIMULATION AND IMPLEMENTATION MONITORING SYSTEM FOR SYSTEM CONTROL C4 FEEDING PUMP FOR FEED VAPORIZATION IN THE BUTADIENE PLANT

2020 ◽  
Vol 1 (1) ◽  
pp. 31-35
Author(s):  
Fahmi Yunistyawan ◽  
Yunistyawan J Berchmans ◽  
Gembong Baskoro
Keyword(s):  
Motor Control ◽  
Control System ◽  
Field Operator ◽  
System Control ◽  
Variable Speed ◽  
Variable Speed Drive ◽  
Software And Hardware ◽  
Discharge Pressure ◽  
Selection Of

This study implements the auto start control system on an electric motor 3 phase C4Feeding pump when the discharge pressure is low-low (4.3 kg /cm²). The C4 feeding pumpmotor was initially manually operated from the local control station, this was very ineffectiveand inefficient because it still relied on the field operator to operate the pump motor and whenthe plant was in normal operating it is very risk if the field operator late to operate motor then itwill impact to quality of the product, and if the delay time to operate motor is too long then planthave to shut down, therefore improvement is needed in the C4 feeding pump motor controlsystem. In this paper, various types of 3-phase motor control are explained which allow it to beapplied to the C4 feeding pump motor that are on-off, inverter, and variable speed drive andefficient selection of the three systems control of the motor. Software and hardware used in thisthesis work are DCS CENTUM VP Yokogawa.

Thomas More’s Correspondence in a Spanish Ambiance

Moreana ◽  
2002 ◽  
Vol 39 (Number 149) (1) ◽  
pp. 41-60 ◽  
Author(s):  
Eugenio M. Olivares Merino
Keyword(s):  
The Subject ◽  
Selection Of

The recent reprinting of Álvaro de Silva’s 1998 edition of a selection of More’s letters prompts the author to examine the subject of Spanish translations of More, and of de Silva’s general commentary on More’s correspondence and on his relationship to other humanists. The author reflects on aspects of More’s personality as exposed in his letters and uses what he finds as a corrective to several biographical misconceptions. He points out the strengths and weaknesses of de Silva’s work and compares it with that of other translators, particularly Elizabeth Rogers, and notes the particularly Spanish quality of de Silva’s edition.

COMBINATORIAL POLYNOMIALLY COMPUTABLE CHARACTERISTICS OF SUBSTITUTIONS AND THEIR PROPERTIES

2020 ◽  
Vol 7 (2) ◽  
pp. 34-41
Author(s):  
VLADIMIR NIKONOV ◽  
◽  
ANTON ZOBOV ◽  
Keyword(s):  
Mathematical Expectation ◽  
Point Of View ◽  
Small Range ◽  
Computational Point ◽  
Wide Range ◽  
Bijective Function ◽  
The Difference ◽  
Element Base ◽  
Selection Of

The construction and selection of a suitable bijective function, that is, substitution, is now becoming an important applied task, particularly for building block encryption systems. Many articles have suggested using different approaches to determining the quality of substitution, but most of them are highly computationally complex. The solution of this problem will significantly expand the range of methods for constructing and analyzing scheme in information protection systems. The purpose of research is to find easily measurable characteristics of substitutions, allowing to evaluate their quality, and also measures of the proximity of a particular substitutions to a random one, or its distance from it. For this purpose, several characteristics were proposed in this work: difference and polynomial, and their mathematical expectation was found, as well as variance for the difference characteristic. This allows us to make a conclusion about its quality by comparing the result of calculating the characteristic for a particular substitution with the calculated mathematical expectation. From a computational point of view, the thesises of the article are of exceptional interest due to the simplicity of the algorithm for quantifying the quality of bijective function substitutions. By its nature, the operation of calculating the difference characteristic carries out a simple summation of integer terms in a fixed and small range. Such an operation, both in the modern and in the prospective element base, is embedded in the logic of a wide range of functional elements, especially when implementing computational actions in the optical range, or on other carriers related to the field of nanotechnology.

Spatial Autocorrelation in the Study of Neighbourhoods towards Smart Cities: Empirical Evidence from Kerman, Iran

2012 ◽  
Vol 9 (2) ◽  
pp. 1
Author(s):  
Asra Hosseini
Keyword(s):  
Spatial Autocorrelation ◽  
Urban Areas ◽  
Smart Cities ◽  
Moran’S I ◽  
Moran's I ◽  
Urban Planner ◽  
Universal Feature ◽  
Autocorrelation Method ◽  
Selection Of

From earliest cities to the present, spatial division into residential zones and neighbourhoods is the universal feature of urban areas. This study explored issue of measuring neighbourhoods through spatial autocorrelation method based on Moran's I index in respect of achieving to best neighbourhoods' model for forming cities smarter. The research carried out by selection of 35 neighbourhoods only within central part of traditional city of Kerman in Iran. The results illustrate, 75% of neighbourhoods' area in the inner city of Kerman had clustered pattern, and it shows reduction in Moran's index is associated with disproportional distribution of density and increasing in Moran's I and Z-score have monotonic relation with more dense areas and clustered pattern. It may be more efficient for urban planner to focus on spatial autocorrelation to foster neighbourhood cohesion rather than emphasis on suburban area. It is recommended characteristics of historic neighbourhoods can be successfully linked to redevelopment plans toward making city smarter, and also people's quality of life can be related to the way that neighbourhoods' patterns are defined. 

Spatial Autocorrelation in the Study of Neighbourhoods towards Smart Cities: Empirical Evidence from Kerman, Iran

2012 ◽  
Vol 9 (2) ◽  
pp. 1
Author(s):  
Asra Hosseini
Keyword(s):  
Spatial Autocorrelation ◽  
Smart Cities ◽  
Moran’S I ◽  
Moran's I ◽  
Urban Planner ◽  
Universal Feature ◽  
Autocorrelation Method ◽  
Selection Of ◽  
Monotonic Relation

From earliest cities to the present, spatial division into residential zones and neighbourhoods is the universal feature ofurban areas. This study explored issue ofmeasuring neighbourhoods through spatial autocorrelation method based on Moran's I index in respect of achieving to best neighbourhoods' model for forming cities smarter. The research carried out by selection of 35 neighbourhoods only within central part of traditional city of Kerman in Iran. The results illustrate, 75% ofneighbourhoods, area in the inner city of Kerman had clustered pattern, and it shows reduction in Moran's index is associated with disproportional distribution of density and increasing in Moran's I and Z-score have monotonic relation with more dense areas and clustered pattern. It may be more efficient for urban planner to focus on spatial autocorrelation to foster neighbourhood cohesion rather than emphasis on suburban area. It is recommended characteristics of historic neighbourhoods can be successfully linked to redevelopment plans toward making city smarter, and also people's quality of life can be related to the way that neighbourhoods' patterns are defined.

METHODS OF NETWORK COMMUNICATIVE COMPETENCE DEVELOPING WHEN PREPARING FUTURE TEACHERS FOR PROFESSIONAL ACTIVITIES IN THE ELECTRONIC EDUCATIONAL ENVIRONMENT

2020 ◽  
Vol 22 (12) ◽  
pp. 21-27
Author(s):  
Kostikova N.A.
Keyword(s):  
Teaching Practice ◽  
Communicative Competence ◽  
Educational Environment ◽  
Learning Technologies ◽  
Future Teachers ◽  
Electronic Information ◽  
Professional Activities ◽  
E Learning ◽  
Selection Of

Currently, in the context of the widespread use of e-learning technologies and distance educational technologies, it is necessary to train future teachers, taking into account the peculiarities of solving professional problems in an electronic information and educational environment, to develop students' relevant competencies, including network communicative competence. Despite the large number of studies devoted to the communicative aspect of the teacher's activities, the problem of the formation of network communicative competence in the electronic information and educational environment has not been sufficiently studied. Based on the analysis of scientific literature, the results of the questionnaire survey of students, some methods of forming network communicative competence in future teachers in the study of various disciplines, in the course of teaching practice, and scientific research are proposed. The analysis of the conditions and factors that determine the choice of methods for the formation of the specified competence has been carried out. These factors are associated with the teachers' perception of the peculiarities of communication in the electronic information and educational environment, the didactic and communicative potential of resources and tools of the electronic information and educational environment, the choice of methods and technologies for organizing interaction, the selection of educational material that allows the development of components of network communicative competence, the design of tasks and exercises for the development of network communicative competence, the choice of modes, schemes and forms of organization of interaction, the organization of feedback, control of the level of formation of the network communicative competence, the implementation of reflection. The formed network communicative competence will contribute to a more effective solution by the teacher of communicative tasks in the electronic information and educational environment, which will improve the quality of training of future teachers in the electronic information and educational environment.

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