Academic literature on the topic 'Ground-Return Parameters'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Ground-Return Parameters.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Journal articles on the topic "Ground-Return Parameters"

1

E., A. Saafan. "Investigating the Impact of Ground-Return Parameters on Transitional Voltages at Switching-Off Unloaded Power Transmission Lines." Engineering and Technology Journal 9, no. 08 (2024): 4724–34. https://doi.org/10.5281/zenodo.13269398.

Full text
Abstract:
The electrical parameters calculations of the overhead transmission lines are very important to the areas concerned to electromagnetic compatibility and transitional processes in power systems. Therefore, accurate calculations of these parameters were performed in this research, taking into account the ground-return parameters (Carson correction factors). The return parameters of the homogenous ground (one-layered ground) the overhead transmission line passes over were taken into consideration via using the actual value of the ground resistivity. In this research, the effect of ground-return parameters on transitional voltages at switching-off an unloaded transmission line using SF<sub>6</sub>&nbsp;circuit-breaker was recorded and clarified. As a result, when the ground-return parameters are taken into account, the overall transmission line inductance increases. This has an obvious impact on the rate of rise of recovery voltage for the SF<sub>6</sub> circuit-breaker inter-contact space, that consequently affects the transitional voltages during switching-off process.
APA, Harvard, Vancouver, ISO, and other styles
2

Li, Zhen, Jinliang He, Bo Zhang, and Zhanqing Yu. "Influence of frequency characteristics of soil parameters on ground-return transmission line parameters." Electric Power Systems Research 139 (October 2016): 127–32. http://dx.doi.org/10.1016/j.epsr.2015.07.020.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Machado, M. V. M., J. A. Brandao Faria, and J. F. Borges da Silva. "Ground return effect on wave propagation parameters of overhead power cables." IEEE Transactions on Power Delivery 5, no. 2 (1990): 825–32. http://dx.doi.org/10.1109/61.53089.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

A., I. A. Rahman, A. Bahari M., A. Baharudin Z., A. Zulkefle A., Zainon M., and A. M. Hanafiah M. "Sub Microsecond Analysis of Negative Cloud-to-Ground Lightning Flashes." Indonesian Journal of Electrical Engineering and Computer Science 11, no. 2 (2018): 711–17. https://doi.org/10.11591/ijeecs.v11.i2.pp711-717.

Full text
Abstract:
This paper expounds a software development for the identification of lightning discharged in cloud-to-ground flashes. The study was to reduce a misleading detection of the electric field radiation of lightning discharged profile by considering the important parameters of sub microseconds structure of lightning`s first return stroke. The software built in MATLAB. The software development considered the important parameters of the first return strokes such as peak value, zero crossing, rising time and fast transition time. This study used a modelling technique for training and patterning 19 return strokes from electric radiation field generated by the negative cloud-ground lightning flashes recorded in Universiti Teknikal Malaysia Melaka.19 return strokes data were recorded by using Lecoy HDO4024 with 5 MS/s. The results showed the software recognized the lightning parameters such as peak value, zero crossing, rising time and fast transition time. In conclusion, the software had the potential to decreases the misleading detection of the electric field radiation generated by negative cloud-to-ground lightning flashes.
APA, Harvard, Vancouver, ISO, and other styles
5

Liu, Jiajia, Jianliang Gao, Ming Yang, Dan Wang, and Liang Wang. "Numerical Simulation of Parameters Optimization for Goaf Gas Boreholes." Advances in Civil Engineering 2019 (January 10, 2019): 1–13. http://dx.doi.org/10.1155/2019/3891080.

Full text
Abstract:
In view of the ground drilling of the N2206 working face in Shanxi Wangzhuang Coal Mine, the gas concentration is low and the extraction effect is not good. Fluent computational fluid dynamics software was used to simulate the ground extraction drilling position of the N2206 working face in the goaf (the distance from the top of the coal seam and the distance from the return to the wind). The numerical simulation results show that when the final hole of the ground extraction hole in the goaf is 16 m from the roof of the coal seam and the distance from the return air is 45 m, the extraction effect is optimal. The average extraction gas volume is 9.78 m3/min, and the average extraction gas concentration is 43.95%, the best extraction effect is obtained. After optimizing the ground drilling position in the goaf and combining with the site implementation, the maximum gas scouring amount of the extraction is 12.59 m3/min, which is 3.42 m3/min higher than the original. The maximum gas concentration of extraction was 63.54%, which was 28.82% higher than the original. After optimization, the gas concentration of the extraction is more than 30%, and the extraction effect is very good. Field application results further validate the reliability of theoretical analysis and numerical simulation results.
APA, Harvard, Vancouver, ISO, and other styles
6

Lima, Antonio C. S., Rodolfo A. R. Moura, Marco Aurélio O. Schroeder, and Maria Teresa Correia de Barros. "Assessment of different formulations for the ground return parameters in modeling overhead lines." Electric Power Systems Research 164 (November 2018): 20–30. http://dx.doi.org/10.1016/j.epsr.2018.07.011.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Garg, Anshuman, and Anjana Goen. "Compact Patch Antenna Parameters Integrating Using Left-Handed Meta Material at 2.41GHz." International Journal of Electrical and Electronics Research 2, no. 3 (2014): 21–24. http://dx.doi.org/10.37391/ijeer.020301.

Full text
Abstract:
This paper propose a new generation of antenna design that applies Meta material properties at the height of 3.2mm above from the ground Plane. Paper also analyzed the performance of Rectangular Micro strip Patch Antenna with and without using the Meta material structure. All antenna parameters such as Return Loss, Gain, Directivity and Band width were measured. The main focus of this paper was to improve Return loss so that Patch antenna used for wide band applications. The additional features were its compact size and used in multiband operation.
APA, Harvard, Vancouver, ISO, and other styles
8

Tselentis, G.-A., and L. Danciu. "Probabilistic seismic hazard assessment in Greece – Part 1: Engineering ground motion parameters." Natural Hazards and Earth System Sciences 10, no. 1 (2010): 25–39. http://dx.doi.org/10.5194/nhess-10-25-2010.

Full text
Abstract:
Abstract. Seismic hazard assessment represents a basic tool for rational planning and designing in seismic prone areas. In the present study, a probabilistic seismic hazard assessment in terms of peak ground acceleration, peak ground velocity, Arias intensity and cumulative absolute velocity computed with a 0.05 g acceleration threshold, has been carried out for Greece. The output of the hazard computation produced probabilistic hazard maps for all the above parameters estimated for a fixed return period of 475 years. From these maps the estimated values are reported for 52 Greek municipalities. Additionally, we have obtained a set of probabilistic maps of engineering significance: a probabilistic macroseismic intensity map, depicting the Modified Mercalli Intensity scale obtained from the estimated peak ground velocity and a probabilistic seismic-landslide map based on a simplified conversion of the estimated Arias intensity and peak ground acceleration into Newmark's displacement.
APA, Harvard, Vancouver, ISO, and other styles
9

Geis-Schroer, Johanna, Sebastian Hubschneider, Lukas Held, et al. "Modeling of German Low Voltage Cables with Ground Return Path." Energies 14, no. 5 (2021): 1265. http://dx.doi.org/10.3390/en14051265.

Full text
Abstract:
In this contribution, measurement data of phase, neutral, and ground currents from real low voltage (LV) feeders in Germany is presented and analyzed. The data obtained is used to review and evaluate common modeling approaches for LV systems. An alternative modeling approach for detailed cable and ground modeling, which allows for the consideration of typical German LV earthing conditions and asymmetrical cable design, is proposed. Further, analytical calculation methods for model parameters are described and compared to laboratory measurement results of real LV cables. The models are then evaluated in terms of parameter sensitivity and parameter relevance, focusing on the influence of conventionally performed simplifications, such as neglecting house junction cables, shunt admittances, or temperature dependencies. By comparing measurement data from a real LV feeder to simulation results, the proposed modeling approach is validated.
APA, Harvard, Vancouver, ISO, and other styles
10

Dandotiya, Vijay, and Chetan Pathak. "Enhancement in RMPA Parameters by Rhombus Connected With Circle Meta Material Structure Using at 1.9 GHz." International Journal of Electrical and Electronics Research 4, no. 1 (2016): 43–45. http://dx.doi.org/10.37391/ijeer.040110.

Full text
Abstract:
Author proposed a new design of meta-material to provide advancement into the factors of the rectangular microstrip patch antenna (RMPA) “Enhancement in RMPA parameters Rhombus Connected With Circle Meta material structure high using at 1.9GHz” As a rectangular microstrip patch antenna is designed at a height of 1.6mm &amp; Left handed Meta material structure is designed at a height of 3.2mm from the ground plane by using CST-MWS software. The resonance frequency 1.9GHz of the designed antenna is using as a high frequency. This paper mainly worked on return loss. The Return loss of the proposed antenna reduced to -31,16dB &amp; bandwidth is increased up to 41.9MHz. This antenna is small size, cheap, compact and easy to fabricate, and achieve good radiation characteristics with higher return loss. In this paper return loss basically defined as system becomes stable with reduced return loss.
APA, Harvard, Vancouver, ISO, and other styles
More sources

Dissertations / Theses on the topic "Ground-Return Parameters"

1

Wan, Mohd Jaafar Wan Shafrina Binti. "Individual tree detection and modelling above-ground biomass and forest parameters using discrete return airborne LiDAR data." Thesis, University of Edinburgh, 2018. http://hdl.handle.net/1842/31143.

Full text
Abstract:
Individual tree detection and modelling forest parameters using Airborne Laser Scanner data (Light Detection and Ranging (LiDAR) is becoming increasingly important for the monitoring and sustainable management of forests. Remote sensing has been a useful tool for individual tree analysis in the past decade, although inadequate spatial resolution from satellites means that only airborne systems have sufficient spatial resolution to conduct individual tree analysis. Moreover, recent advances in airborne LiDAR now provide high horizontal resolution as well as information in the vertical dimension. However, it is challenging to fully exploit and utilize small-footprint LiDAR data for detailed tree analysis. Procedures for forest biomass quantification and forest attributes measurement using LiDAR data have improved at a rapid pace as more robust and sophisticated modelling used to improve the studies. This thesis contains an evaluation of three approaches of utilizing LiDAR data for individual tree forest measurement. The first explores the relationship between LiDAR metrics and field reference to assess the correlation between LiDAR and field data at the individual-tree level. The intention was not to detect trees automatically, but to develop a LiDAR-AGB model based on trees that were mapped in the field so as to evaluate the relationships between LiDAR-type metrics under controlled conditions for the study sites, and field-derived AGB. A non-linear AGB model based on field data and LiDAR data was developed and LiDAR height percentile h80 and crown width measurement (CW) was found to best fit the data as evidenced by and Adj-R2 value of 0.63, the root mean squared error of the model of 14.8% and analysis of the residuals. This paper provides the foundation for a predictive LiDAR-AGB model at tree level over two study sites, Pasoh Forest Reserve and FRIM Forest Reserve. The second part of the thesis then takes this AGB-LiDAR relationship and combines it with individual tree crown delineation. This chapter shows the contribution of performing an automatic individual tree crown delineation over the wider forest areas. The individual tree crown delineation is composed of a five-step framework, which is unique in its automated determination of dominant crown sizes in a forest area and its adaption of the LiDAR-AGB model developed for the purpose of validation the method. This framework correctly delineated 84% and 88% of the tree crowns in the two forest study areas which is mostly dominated with lowland dipterocarp trees. Thirdly, parametric and non-parametric modelling approaches are proposed for modelling forest structural attributes. Selected modelling methods are compared for predicting 4 forest attributes, volume (V), basal area (BA), height (Ht) and aboveground biomass (AGB) at the species level. The AGB modelling in this paper is extracted using the LiDAR derived variables from the automated individual tree crown delineation, in contrast to the earlier AGB modelling where it is derived based on the trees that were mapped in the field. The selected non-parametric method included, k-nearest neighbour (k-NN) imputation methods: Most Similar Neighbour (MSN) and Gradient Nearest Neighbour (GNN), Random Forest (RF) and parametric approach: Ordinary Least Square (OLS) regression. To compare and evaluate these approaches a scaled root mean squared error (RMSE) between observed and predicted forest attribute sampled from both forest site was computed. The best method varied according to response variable and performance measure. OLS regression was to found to be the best performance method overall evidenced by RMSE after cross validation for BA (1.40 m2), V (1.03 m3), Ht (2.22 m) and AGB (96 Kg/tree) respectively, showed its applicability to wider conditions, while RF produced best overall results among the non-parametric methods tested. This thesis concludes with a discussion of the potential of LiDAR data as an independent source of important forest inventory data source when combined with appropriate designed sample plots in the field, and with appropriate modelling tools.
APA, Harvard, Vancouver, ISO, and other styles

Book chapters on the topic "Ground-Return Parameters"

1

Jayananda Singh, Samom, Rajesh Kumar, and M. M. Dixit. "Study Analysis of Printed Monopole Antenna for C and X Band Application." In Frontiers in Artificial Intelligence and Applications. IOS Press, 2022. http://dx.doi.org/10.3233/faia220525.

Full text
Abstract:
In this design, dimension of the proposed antenna is 20 × 25 × 1.6 mm3 with FR4 substrate having circular patch fed with co-planar waveguide (CPW) that operates at numerous resonance frequencies between 5 and 10 GHz. The proposed antenna can be used well for low range communication transceivers in the C and X bands, according to simulation results. The optimal parameters for UWB antenna are the fractional bandwidth, which should be greater than 85%, and VSWR, which is another parameter. For the best and most efficient technique of using printed monopole antenna, the range of Ultra wideband (UWB) bandwidth should be lower than 2. Simulate data suggest that the proposed antenna has outstanding impedance matching capabilities, achieving a peak gain of 8 dBi. Results indicate that the ground plane’s dimensions of 15.9 mm and 11.4 mm are the most suitable for UWB due to its return loss of -41.86 dB, fractional bandwidth of about 89%, and Voltage standing wave ratio(VSWR) of less than 2 within the frequency spectrum. This modified prototype antenna has a decent, omnidirectional radiation pattern.
APA, Harvard, Vancouver, ISO, and other styles
2

Kumar Parashar, Ashish. "A Seismic Hazard Assessment of North Chhattisgarh (India)." In Natural Hazards - New Insights [Working Title]. IntechOpen, 2023. http://dx.doi.org/10.5772/intechopen.109490.

Full text
Abstract:
Chhattisgarh, located in Central India, has been carved out of Madhya Pradesh to become the 26th state of the Indian Union. North Chhattisgarh is addressed by the tribal population. In the current study, an endeavor has been made to carry out the seismic hazard analysis for the major district headquarters of north Chhattisgarh, considering the local site effects and developing a seismic zone map for north Chhattisgarh. Seismic hazard analysis has been done for major district headquarters Ambikapur, Baikunthpur [Koria], Korba, and Jashpurnagar of north Chhattisgarh, using seismotectonic information. All earthquake sources and past seismic events have been considered within a radius of 300 km for the headquarters, applying deterministic and probabilistic seismic hazard analysis approaches. The seismic parameters and peak ground acceleration at the bedrock level for the district headquarters of north Chhattisgarh have been estimated. Using probabilistic seismic hazard analysis, hazard curves have been developed for each district headquarters. Alternatively, for peak ground acceleration of 0.05 g, 0.1 g, and 0.15 g return periods have been estimated for the study area. The probabilities of exceedance for 2% and 10% for 50 years have also been estimated for the study area. The current study throws light on the design and construction of vital civil engineering structures near and around the seismically active headquarters in northern Chhattisgarh.
APA, Harvard, Vancouver, ISO, and other styles
3

Jeya Sheela, J. Joselin, N. Duraichi, B. Jeyapoornima, and M. Logeshwaran. "Patch Antenna Design for 2.4 GHz for On-Off Body Communication." In Advanced Computing Solutions for Healthcare. BENTHAM SCIENCE PUBLISHERS, 2025. https://doi.org/10.2174/9789815274134125010024.

Full text
Abstract:
On-body communication is a crucial technology, finding applications ranging from healthcare monitoring to IoT connectivity. Using antennas, on-body communication technology exploits specific frequency bands and tailored antenna designs to facilitate efficient data exchange between devices on or near the human body. This study delves into patch antenna designs customized for on-off body communication at 2.4GHz frequencies. As the demand surges for seamless connectivity with diminutive, inconspicuous form factors, an in-depth exploration of antenna design becomes indispensable. The antenna, crafted with FR-4 (a lossy material) possessing a dielectric constant of 4.4, employs copper for the patch and ground layers. Simulation is carried out utilizing the CST Studio Suite, confirming and documenting key antenna parameters: Gain of 5.65dB, bandwidth of 96.8MHz, return loss of -41.83dB, and VSWR of 1.05. Through simulation, a thorough analysis of the antenna's performance in both free space and on the body is conducted, unveiling its exceptional performance in these scenarios. Furthermore, the proposed design optimizations exhibit resilience against environmental factors, making them well-suited for practical on-body communication applications.
APA, Harvard, Vancouver, ISO, and other styles
4

Hidalgo Cesar and Vega Johnny. "Risk Estimation in Urban Buildings by Landslides Triggered by Earthquakes and Rainfall (Medellin-Colombia)." In From Fundamentals to Applications in Geotechnics. IOS Press, 2015. https://doi.org/10.3233/978-1-61499-603-3-2892.

Full text
Abstract:
This article presents a risk modeling in buildings by landslides triggered by earthquakes and rainfall in the city of Medellin using a geographic information system (GIS). For this, a computer model that considers topographic, geological, geotechnical and hydrological characteristics of the study area was implemented to determine landslide hazard by evaluating the stability of slopes using pseudo static Newmark Method, including a probabilistic approach technique based on the first order and second moment -FOSM-. The approach for the assessment of physical vulnerability of buildings in the study area was conducted through structural fragility indexes that consider the definition of the level of damage to buildings through event trees using a cadastral inventory data of the municipality of Medellin. The routine calculates the probability of a landslide to occur given that an earthquake produces a horizontal ground acceleration (Ah), considering the uncertainty of the geotechnical parameters and the conditions of soil saturation for the effect of previous rainfall in the area, then multiply such values with the structural fragility indexes values in order to estimate the damage indices of buildings, which are associated with the risk when considering the relevant economic variable to the replacement value of such structures from assessed values. The implemented model is able to quantify the risk caused by this type of disaster in an area of the city considering different values of Ah, and also an analysis of the costs arising from damage to the houses in the study area was carried out under different scenarios and structural conditions in which it was found that under an assumed scenario in which all the buildings in the study area meet the requirements of the Colombian Standard for Design and Construction Earthquake Resistant, reducing the costs arising by the effect of a disaster sliding round the order of 70% compared to the condition of the actual structural scenario to the maximum horizontal ground acceleration expected in the city for an earthquake with a return period of 475 years according to the study of seismic microzonation in 2002.
APA, Harvard, Vancouver, ISO, and other styles
5

Ramanna, C. K., and G. R. Dodagoudar. "Effect of Epicenter Data Inconsistency in Determining Bandwidth and Its Subsequent Use in Hazard Analysis for Chennai Using Kernel Smoothing Approach." In Civil and Environmental Engineering. IGI Global, 2016. http://dx.doi.org/10.4018/978-1-4666-9619-8.ch065.

Full text
Abstract:
The most important parameter in the kernel density estimator is the bandwidth or spread or window width. The bandwidth of the kernel density estimator, which follows the power law, is determined using the nearest neighborhood technique for the earthquake catalog which is divided into bins. For reliable hazard estimates, the magnitude bins used in developing the power law and estimating the spatial activity rate density function should be the same. It is important that consistency be maintained between the earthquake epicenters used in determining the bandwidth and the epicenters to which the bandwidth is applied subsequently. In this paper, the effect of epicenter data inconsistency on hazard estimates for various return periods for Chennai is evaluated. Two methods of binning are used, one in which the epicenters used in deriving the bandwidth is in line with the epicenters used in arriving at the spatial activity rate and the other where the epicenters used in deriving the bandwidth are just grouped by dividing the catalogue into equal bins. Seismic hazard estimations are compared using these two approaches of forming the magnitude bins for Chennai, Tamil Nadu, India. The peak ground acceleration (PGA) values obtained from Binning Methods 1 and 2 for 475 years return period are 0.0955g and 0.0802g respectively. The difference in PGA and peak spectral acceleration (PSA) from the two binning methods ranges from 20 to 10% with respect to Binning Method 1 for the return periods of 72 to 2475 years.
APA, Harvard, Vancouver, ISO, and other styles

Conference papers on the topic "Ground-Return Parameters"

1

Nicoara, Bogdan, and Stefania Ioan. "Ground Return Overhead Lines Parameters." In 1994_EMC-Europe_Roma. IEEE, 1994. https://doi.org/10.23919/emc.1994.10777689.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Finckenor, Jeff, Terry Baker, Christopher Wallace, Michael Chandler, and Scott Engelmeyer. "Establishing Rotorcraft Component Fatigue Lives using SUMS Data and a Partial Usage Spectrum Approach for the MH-47G Chinook." In Vertical Flight Society 72nd Annual Forum & Technology Display. The Vertical Flight Society, 2016. http://dx.doi.org/10.4050/f-0072-2016-11472.

Full text
Abstract:
Lives of fatigue critical components for Army aircraft are typically established based on component strength from ground test, loads for each regime from flight test, and aircraft usage in each regime from engineering and aircrew judgement. This paper documents the first time that an Army platform has had component fatigue lives defined with usage monitored by the Structural Usage Monitoring System (SUMS). SUMS uses aircraft parameters to identify the regime at any given time. The time in recognized regimes is summed up to generate a spectrum of time spent in each regime. The Partial Regime Recognition Spectrum used here identified specific regimes that had a significant effect on part life and concentrated on identifying only those regimes. Time in other 'unrecognized' regimes was prorated based on the legacy spectrum. The SUMS system is validated using scripted flights, as well as by cross checking against a spectrum generated via pilot interviews. Six components were addressed with life changes of -1.5%, +24%, +33%, +44%, +45% and +124%, with an annual return of $1M as well as reduced maintenance burden and increased readiness.
APA, Harvard, Vancouver, ISO, and other styles
3

Ui Ain, Noor, Farhan Mahmood, Amna Shaukat, and Mohammad E. M. Rizk. "Evaluation of Ground Parameters on Lightning-Induced Over-Voltages Considering Various Return Stroke Models." In 2022 36th International Conference on Lightning Protection (ICLP). IEEE, 2022. http://dx.doi.org/10.1109/iclp56858.2022.9942538.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Kerscher, Martin, Heike Krasting, and Ulrich G. Oppel. "Retrieval of environmental parameters from multiply-scattered return signals of ground-based and airborne lidars." In European Symposium on Optics for Environmental and Public Safety, edited by Peter Fabian, Volker Klein, Maurus Tacke, Konradin Weber, and Christian Werner. SPIE, 1995. http://dx.doi.org/10.1117/12.221068.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Alipio, Rafael, Naiara Duarte, and Farhad Rachidi. "Comparison of Different Formulations to Compute the Ground Return Parameters in the Analysis of High-Frequency Pulse Propagation Along a Wire Above a Lossy Ground." In 2023 XXXVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS). IEEE, 2023. http://dx.doi.org/10.23919/ursigass57860.2023.10265582.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Hause, Terry, and Jianping Sheng. "AN IMPROVED METHOD TO MORE ACCURATELY ASSESS THE JOHNSON-COOK HIGH STRAIN-RATE DEFORMATION MATERIAL MODEL PARAMETERS - PART I." In 2024 NDIA Michigan Chapter Ground Vehicle Systems Engineering and Technology Symposium. National Defense Industrial Association, 2024. http://dx.doi.org/10.4271/2024-01-3553.

Full text
Abstract:
&lt;title&gt;ABSTRACT&lt;/title&gt; &lt;p&gt;Two relevant materials found in ground vehicle underbody armor/hull designs are Aluminum 2139-T8 and RHA Steel (Class I). These are 2 very important materials that need a thorough understanding of their high-strain rate behavior. The Johnson-Cook Deformation (JC-D) model at this time is the most preferred constitutive material model to utilize for high-strain (large deformation) blast simulations. The JC-D Model contains five empirically-based input parameters which can be determined traditionally through a series of uniaxial laboratory tests where each target parameter is isolated, while the remaining parameters are held constant. There are many criticisms and problems with this approach. The objective of this two part paper is to present and adopt a more accurate approach with less criticism to the determination of these five input parameters through both a sensitivity study to determine which input parameters are the most sensitive to a particular chosen response which in return will be utilized to conduct a numerical / empirical physics-based approach known as Numerical Optimization. Part 1 will focus on the sensitivity study while part 2 will focus on the optimization study and validations to determine optimal values for the JC-D Material Model Input Parameters. In part2, these optimized material input parameters will be leveraged to run shock tube simulations after which validations with various shock-tube blast load tests under various geometrical and or loading conditions such as plate thickness, pressure loading, boundary conditions, etc. will be made.&lt;/p&gt;
APA, Harvard, Vancouver, ISO, and other styles
7

Popović, Nikola, and Jelena Pejović. "SEISMIC PERFORMANCE EVALUATION OF EXISTING RC HIGH-RISE BUILDING IN MONTENEGRO." In 2nd Croatian Conference on Earthquake Engineering. University of Zagreb Faculty of Civil Engineering, 2023. http://dx.doi.org/10.5592/co/2crocee.2023.13.

Full text
Abstract:
Seismic performance evaluation of buildings represents a basis for seismic vulnerability and risk assessment. Considering the importance of seismic risk assessment nowadays, as one of the most actual topics in earthquake engineering, in this paper, a seismic performance evaluation of an existing RC high-rise building with walls on the Montenegrin coast, an area with high seismic risk, is conducted. The aim of the paper is to evaluate the performance of this type of buildings built on the Montenegrin coast and thus contribute to their vulnerability assessment. Two EN 1998-1 fundamental requirements are examined for seismic performance evaluation: non-collapse and damage limitation requirements. A non-linear 3D building model is defined in the PERFORM 3D software. Modelling is performed by taking into account realistic characteristics of used materials, constructed geometry of structural elements and realistic loads. Non-linear time history analyses are performed using 112 ground motion records, from which 56 are used for evaluation of non-collapse requirement and the other 56 for evaluation of damage limitation requirement. Ground motion records were selected and scaled according to EN 1998-1. Peak horizontal ground acceleration of 0.34g for ground motions with a return period of 475 years for checking non-collapse requirement is adopted, and 0.15g for ground motions with a return period of 95 years for checking damage limitation requirement. Inter-storey drift, wall rotations, dilatations in structural elements and shear capacity are the main parameters that are analysed to obtain conclusions on acceptable seismic performance. Useful conclusions related to the seismic performance of existing RC high-rise buildings of structural systems with ductile walls built on the Montenegrin coast are pointed out.
APA, Harvard, Vancouver, ISO, and other styles
8

Mun, Junghyon, and Yong Tao. "Development of a Tool to Calibrate Vertical Ground Heat Exchanger Model Using Optimization." In ASME 2013 7th International Conference on Energy Sustainability collocated with the ASME 2013 Heat Transfer Summer Conference and the ASME 2013 11th International Conference on Fuel Cell Science, Engineering and Technology. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/es2013-18274.

Full text
Abstract:
This paper presents a calibration process and its tool of the vertical ground heat exchanger model used in a building energy simulation program, Energyplus. To adequately analyze the performance of the system, calibration of the system model is crucial. The calibration procedure is to estimate input data of the simulation that match the results of the simulation with measured data by an inverse method. The vertical ground loop heat exchanger consists of ground and borehole systems. The thermal properties of the borehole system usually can be found from manufacturer’s data. However, the thermal property of the ground is hard to evaluate. In this paper, an evaluation tool of the thermal properties of the ground around the borehole is developed using Matlab. This tool consists of three submodels. The first one is a G-function curve fit model which represents the relationship between variation of thermal conductivity and g-function values. The second model is the vertical ground loop heat exchanger model which predicts the return water temperature from a ground loop heat exchanger using the short time response factor method. The vertical ground loop heat exchanger model in Energyplus is converted to Matlab code and integrated into the calibration model for this research. The last sub-model is the optimization model that uses the Nelder and Mead simplex optimization scheme to find parameters which minimize the difference between the simulation results and the field measurement data. This tool estimates the ground thermal propertiesusing an optimization scheme based on data collected from field measurement. Far field ground temperature and the ground thermal conductivity are estimated to be used as input data of the vertical ground loop heat exchanger model in Energyplus. This program is validated using a case study which is performed for an actual building, ZOE which is located in the University of North Texas and its system. 2 weeks’ measurement data were compared with the simulation result. The average deviation between the simulation result and measurement data for 2 weeks is 0.27 °C.
APA, Harvard, Vancouver, ISO, and other styles
9

Siddique, Sabbir, and Faria Sharmin. "Seismic demand assessment for 20km long Elevated Expressway in Chattogram, Bangladesh." In IABSE Congress, New Delhi 2023: Engineering for Sustainable Development. International Association for Bridge and Structural Engineering (IABSE), 2023. http://dx.doi.org/10.2749/newdelhi.2023.0150.

Full text
Abstract:
&lt;p&gt;Bangladesh is surrounded by 2500km long Himalayan Frontal Thrust at North and by Indo-Myanmar Subduction zone at the East. These two fault zones are primary source of many large historic earthquakes that had occurred along the border of Bangladesh extended from North and wrapping East. The Chattogram region of Bangladesh is hilly and experiences frequent smaller earthquake shaking compare to other area of the country.&lt;/p&gt;&lt;p&gt;The Elevated Expressway (EEW) project being constructed from Airport to Lalkhan Bazar in Chattogram city by Chattogram Development Authority (CDA) is almost 20km long elevated bridge structure made of Concrete and partly of Steel that runs through a much-crowed habitat. Due to scarcity of land at grade, the EEW is supported on single pier thus with no redundancy in Earthquake Resistance System (ERS).&lt;/p&gt;&lt;p&gt;Bangladesh National Building Code (BNBC) provides only Peak Ground Acceleration (PGA) for 2475 years return period. The Country is divided into four seismic zones with PGA varies from 0.12g to 0.36g. Data required for seismic analysis of a bridge using AASHTO Code requires PGA associated with 1000 years return period, horizontal response spectral acceleration coefficients for different structural periods are not readily available in BNBC. Interpolation of data from only two available data [225yrs. from BNBC/93 and 2475 yrs. from BNBC/2020] may not reflect the correct risk scenario.&lt;/p&gt;&lt;p&gt;To calculate the seismic risk for EEW Project, Probabilistic Seismic Hazard Analysis [PSHA] was done and compared with the data available in the Code to finalize seismic risk parameters for the EEW Project.&lt;/p&gt;
APA, Harvard, Vancouver, ISO, and other styles
10

Ghaith, Fadi A., and Habib Ur Razzaq. "Thermal Performance of Earth-Air Heat Exchanger Systems for Cooling Applications in Residential Buildings." In ASME 2018 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/imece2018-86974.

Full text
Abstract:
This paper addresses the thermal performance of integrating Earth Air Heat Exchanger (EAHE) systems with the conventional air conditioning systems in residential buildings in UAE. The proposed system was designed and simulated using a transient analysis tool TRNSYS. The system components were optimized by evaluating the effect of varying several design parameters on the performance of the system. It was found that the optimized design of the earth tubes could potentially reduce the temperature of the ambient air from 46 °C to around 29 °C, when the earth tubes were buried at 4 meters depth below the ground surface. This pre-cooled fresh (atmospheric) air from earth tubes was then mixed with the return air in the mixing chamber of conventional air cooling systems before supply to the building. In order to assess the system feasibility, the proposed system was modelled and implemented on a realistic case study represented by a four-floor residential building located in Dubai. This building comprised a total roof area of 400 m2 and an annual cooling load requirement of 366 kW. The results showed good potential of savings in terms of lowering the Annual Energy Consumption (AEC) and the consequent reduction in CO2 emissions.
APA, Harvard, Vancouver, ISO, and other styles
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!