Electromagnetic Transients

2021 ◽  
pp. 226-263
Author(s):  
Eleni P. Nicolopoulou ◽  
Panagiotis K. Papastamatis ◽  
Ioannis F. Gonos
Keyword(s):  
Standardized Testing ◽  
Design Guidelines ◽  
International Standards ◽  
Electromagnetic Transients ◽  
Space Systems ◽  
Transient Phenomena ◽  
Testing Procedures ◽  
Physical Mechanisms ◽  
Transient Electromagnetic ◽  
Electromagnetic Disturbances

This chapter aims at presenting the current international standards and the recent bibliography regarding the transient phenomena associated with space systems, with emphasis on the EMC requirements. The first section of the chapter focuses on the description of the physical mechanisms causing transient electromagnetic phenomena in space. The second section reviews the procedures proposed for testing the immunity of space equipment against these transients, as described in the current space standards and in recent bibliography as non-standardized testing procedures. Finally, the last section investigates possible mitigation approaches and design guidelines against these electromagnetic disturbances, essential for every space system designer.

Transient Electromagnetic Phenomena–Standardization and EMC Requirements–Mitigation Techniques

2018 ◽  
pp. 211-247
Author(s):  
Eleni P. Nicolopoulou ◽  
Panagiotis K. Papastamatis
Keyword(s):  
Design Procedure ◽  
Design Guidelines ◽  
International Standards ◽  
Space Application ◽  
Transient Phenomena ◽  
Spacecraft Charging ◽  
Transient Electromagnetic ◽  
Mitigation Techniques

In this chapter, the spacecraft charging effects that lead to ESD events, as well as the associated immunity testing required, are presented in detail and compared to the human-induced discharges, mainly simulated by most commercial ESD generators. Additionally, design guidelines for mitigating the effects of these ESD occurrences, essential for every space application designer, are discussed. Finally, the measurement requirements, as well as the test setups, regarding the immunity testing to power leads transients are described thoroughly. This chapter aims at reviewing the current international standards and the recent bibliography, summarizing and commenting on the EMC requirements, regarding the transient phenomena, pinpointing the differentiations of these standards and their effects on the design procedure and testing creditability.

scholarly journals Assessing Public Open Spaces: A Case of City Nagpur, India

2021 ◽  
Vol 13 (9) ◽  
pp. 4997
Author(s):  
Pritam Ahirrao ◽  
Smita Khan
Keyword(s):  
Open Space ◽  
Well Being ◽  
Design Guidelines ◽  
International Standards ◽  
Free Access ◽  
Optimum Level ◽  
Public Parks ◽  
Diverse Range ◽  
Environmentally Sustainable ◽  
Public Open Space

Major Indian cities have a lower public open space (POS)-capita ratio and do not meet national and international standards. Moreover, factors such as lack of design guidelines for POSs, limited funding, and lack of public participation have affected these limitedly available POSs and made them ineffective and incapable of meeting the contemporary needs of a diverse range of users. Therefore, it is essential to make them not only inclusive, user-friendly, attractive, and efficient, but also socially, economically, and environmentally sustainable in order to serve the various facilities and services at their optimum level. This study includes the assessment of two POSs to identify strengths and deficiencies that affect their character and use. These POSs are public parks, provide free access to users and are located in the city of Nagpur. For assessment, the study proposed the Public Open Space Index (POSI) that combines five aspects: Individual well-being, Inclusiveness, Engagement, Sustainable spaces, and Management.A mixed methods approach was considered for data collection, including a self-administered questionnaire survey and observations.According to the results, POSs have strengths in that they facilitate social cohesion, engagement, and basic facilities. POSs do not encourage equitable access and sustainable practices, which are considered deficiencies.The study helps planners, designers, and parenting authority to develop initiatives to make these limited POSs inclusive, functional, and sustainable.

scholarly journals Controlled Switching of the T402 Transformer in the Križovany 400kV Substation

2010 ◽  
Vol 61 (1) ◽  
pp. 11-19
Author(s):  
František Janíček ◽  
Martin Mucha ◽  
Karol Česnek ◽  
Jozef Kováčik
Keyword(s):  
Control Unit ◽  
Simulation Software ◽  
Transient Phenomena ◽  
Controlled Switching ◽  
Transient Electromagnetic ◽  
Statistical Frequency

Controlled Switching of the T402 Transformer in the Križovany 400kV Substation The paper deals with simulating the circumstances of switching surge and trigger current at switching-in of the T402 autotransformer recently installed in Križovany, with the tests conducted by means of ATP (Alternative Transient Program) simulation software for simulating transient electromagnetic phenomena. The target has been to determine temporal curves for the most critical surge instances against earth and between the phases and the curves for trigger current with and without surge limiters connected, and to determine by means of simulations the size and statistical frequency of switching surges and based on a controlled switching simulation, to describe the elimination of transient phenomena during the process and in reference to the simulations and to operating manual for the PSD02 Siemens control unit, suggest the required configuration settings for the unit.

scholarly journals Las pruebas estandarizadas como forma de medición del nivel de inglés en la educación Colombiana

2020 ◽  
Author(s):  
Jorge Benavides
Keyword(s):  
Standardized Testing ◽  
Field Research ◽  
Foreign Languages ◽  
Measuring Instruments ◽  
Ministry Of Education ◽  
Testing Procedures ◽  
Level Of Knowledge ◽  
To Come ◽  
Globalized World

This article discusses the importance of standardized testing as a means of assessing learning and determining the level of knowledge and use of foreign languages like English. It is very well known that since the second half of the twentieth century efforts were made in order to come up with valid and reliable measuring instruments for linguistic and communicative competence of a person in foreign languages. This began in the area of field research and ongoing reviewing processes to ensure the quality of testing procedures. Today, in a globalized world with many possibilities for mobility of students, teachers, and researchers standardized tests have been popularized and institutionalized in different countries. Colombia has not been the exception and starting from the beginning of this century the Ministry of Education has implemented the standard promoted by the Common European Framework of Reference for Languages which enables standardized measuring levels of English as a foreign language in students, teachers and professionals in general.

scholarly journals Assessment of Standards and Codes Dedicated to CFRP Confinement of RC Columns

Materials ◽  
2019 ◽  
Vol 12 (15) ◽  
pp. 2390 ◽  
Author(s):  
Stefan Kaeseberg ◽  
Dennis Messerer ◽  
Klaus Holschemacher
Keyword(s):  
Reinforced Concrete ◽  
Cross Sections ◽  
Rupture Strength ◽  
Axial Strain ◽  
Design Guidelines ◽  
International Standards ◽  
National Standards ◽  
Rc Columns ◽  
New Findings ◽  
Cfrp Confinement

Reinforced concrete (RC) columns are often placed under confinement to increase their strength and ductility. Carbon fiber reinforced polymer (CFRP) materials have recently been recognized as favorable confinement systems. At present, a number of national standards and codes dedicated to the design of concrete components strengthened with CFRP in general and CFRP confinement in particular are available. These sets of rules provide design equations for confined reinforced concrete columns with circular and rectangular cross sections. Most of the standards and codes exhibit significant differences, including the used predictive models, limitations, observed effects and covered loading conditions. In this paper, five international standards and design guidelines are introduced and discussed. The purpose is to present a constructive and critical assessment of the state-of-the-art design methodologies available for CFRP confined RC columns and to discuss effects not previously considered properly. Therefore, some recent research efforts and findings from the Leipzig University of Applied Sciences are also introduced. The obtained data is used for a comparative study of the guideline predictive equations. Furthermore, it is shown that some new findings concerning the rupture strength and the maximum strength plus accompanying axial strain of a CFRP confined column are suitable to improve the current guidelines.

Correlations between PENCEL Pressuremeter, Cone Penetrometer, and Dilatometer Parameters

2008 ◽  
Vol 2053 (1) ◽  
pp. 65-71 ◽  
Author(s):  
Paul J. Cosentino ◽  
Edward Kalajian ◽  
Farid Messaoud ◽  
Sunil Sundaram ◽  
Thaddeus J. Misilo ◽  
...  
Keyword(s):  
Standardized Testing ◽  
Elastic Moduli ◽  
Soil Disturbance ◽  
Cone Penetrometer ◽  
Testing Procedures ◽  
The Third ◽  
Recorded Data ◽  
Engineering Parameters ◽  
Lift Off ◽  
Friction Reducer

PENCEL pressuremeter (PPMT), cone penetrometer (CPT), and dilatometer (DMT) tests were performed at three Florida sites. Two were sands and the third was clay. The PENCEL was pushed to the test depth using CPT equipment. During PPMT testing, both a smooth cone tip and a cone tip with a friction reducer were evaluated. Standardized testing procedures were followed for all tests. Initial or lift-off pressures (po), elastic moduli (E), and limit pressures (pL) were determined from the PPMT, whereas po and E values were determined from the DMT. CPT testing produced friction and tip resistances. Manual plus digital pressures and volumes were recorded during pressuremeter testing. Correlations were developed within the engineering parameters obtained from the PENCEL and between the PENCEL, cone, and dilatometer engineering parameters. All correlations matched published values. The PENCEL produced excellent correlations between the initial E and pL as well as the initial E and the reload E. Correlations based on digital elastic and reload moduli, from software called APMT, were higher than those based on the other recorded data. From the comparisons, promising correlations were developed between PPMT initial E values and CPT tip resistances. Promising correlations were also developed between PPMT pL and CPT tip resistances. Consistent ratios existed between PPMT and DMT po values as well as PPMT and DMT initial E values. Smooth and friction reducer cone tips evaluation indicated that soil disturbance, associated with the friction reducer, decreases the engineering parameters, and the friction reducer is not recommended.

scholarly journals A Comprehensive Inverter-BESS Primary Control for AC Microgrids

Energies ◽  
2019 ◽  
Vol 12 (20) ◽  
pp. 3810 ◽  
Author(s):  
Michele Fusero ◽  
Andrew Tuckey ◽  
Alessandro Rosini ◽  
Pietro Serra ◽  
Renato Procopio ◽  
...  
Keyword(s):  
Power Control ◽  
Storage System ◽  
Energy Storage System ◽  
International Standards ◽  
Electromagnetic Transients ◽  
Primary Control ◽  
Fast Power ◽  
Voltage Frequency ◽  
Battery Energy ◽  
Fast Control

This paper proposes the design of a comprehensive inverter-BESS primary control capable of providing satisfactory performances both in grid-connected and islanded configurations as required by international standards and grid codes, such as IEEE Std. 1547. Such control guarantees smooth and fast dynamic behavior of the converter in islanded configuration as well as fast power control and voltage-frequency support in grid-connected mode. The performances of the proposed primary control are assessed by means of EMT (ElectroMagnetic Transients) simulations in the dedicated software DIgSILENT PowerFactory® (Germany, Gomaringen) . The simulation results show that the proposed BESS (Battery Energy Storage System) primary control is able to regulate frequency and voltage in Grid-Forming mode independently of the number of paralleled generators. This is achieved adopting a virtual generator technique which presents several advantages compared to the conventional one. Moreover, the proposed control can be switched to Grid-Support mode in order to provide fast control actions to allow frequency and voltage support as well as power control following the reference signals from the secondary level.

Overview of the Air Force Program in Workload Assessment

1980 ◽  
Vol 24 (1) ◽  
pp. 668-668
Author(s):  
Robert D. O'Donnell
Keyword(s):  
Standardized Testing ◽  
Air Force ◽  
Large Scale ◽  
Early Stage ◽  
Point Of View ◽  
Short Term ◽  
Aerospace Medicine ◽  
Testing Procedures ◽  
Medical Division ◽  
Aerospace Medical

The Aerospace Medical Division of the U.S. Air Force has recognized the need to develop a comprehensive program to define assessment techniques presently available in measuring the workload imposed by systems, to develop new techniques, and eventually to standardize the approach used for this purpose. A joint program between the Air Force Aerospace Medical Research Laboratory and the School of Aerospace Medicine has therefore been developed. The short-term program goals are evolved from field requirements determined through large scale surveys, time-line analyses of systems, and other observational techniques. Using these, existing methods for answering workload questions are being evaluated with a goal toward short-term standardization of techniques within the Air Force. From a longer range point-of-view, new metrics, both behavioral and neurophysiological, are being investigated. As sensitive non-obstrusive measures are isolated, they will be incorporated into the standardized testing procedures. Ultimately, the program points toward development of computer modeling techniques to permit man-rating of systems with respect to workload at an early stage of system design.

Enhanced Mechanical-Integrity Characterization of Oilwell Annular Sealants Under In-Situ Downhole Conditions

SPE Journal ◽  
2019 ◽  
Vol 24 (05) ◽  
pp. 2308-2319
Author(s):  
Walmy Cuello Jimenez ◽  
Robert Darbe ◽  
Xueyu Pang
Keyword(s):  
Tensile Strength ◽  
Standardized Testing ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
Axial Loading ◽  
Testing Apparatus ◽  
Testing Procedures ◽  
Preliminary Validation ◽  
Three Samples

Summary In this study, we describe an innovative and novel methodology comprising a high–pressure/high–temperature (HP/HT) in–situ–triaxial–testing apparatus for the measurement of sealant mechanical properties (i.e., compressive strength, Young's modulus, and tensile strength) under simulated downhole conditions. The equipment can be used to perform both curing and testing using the same apparatus, thus eliminating depressurization and cooling of test specimens. Additionally, at minimum, three samples can be tested sequentially for statistical analysis and uncertainty mitigation, along with performing real–time monitoring of total HP/HT shrinkage/expansion. The testing apparatus is rated to 30,000 psi for axial loading, 20,000 psi for confining loading, and 400°F. Preliminary validation of Young's modulus was performed with five different plastic samples, yielding error percentages of less than 5% compared to measurements performed using a standardized loading frame. Compressive– and tensile–strength validations were performed using a 16–lbm/gal cement design, and error percentages of less than 2.5 and 7%, respectively, were obtained compared to standardized testing procedures or other studies of the subject. Moreover, a 16–lbm/gal cement system was also used to help assess the functionality of the testing apparatus under simulated wellbore conditions with temperature and pressure ranging from 80 to 350°F and 3,000 to 8,000 psi, respectively.

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