scholarly journals A New Approach for the Analysis of Deep Convective Events: Thunderstorm Intensity Index

Atmosphere ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 908
Author(s):  
Damjan Jelić ◽  
Maja Telišman Prtenjak ◽  
Barbara Malečić ◽  
Andreina Belušić Vozila ◽  
Otília Anna Megyeri ◽  
...  
Keyword(s):  
Wind Speed ◽  
Temporal Resolution ◽  
Small Area ◽  
Data Sources ◽  
Mountain Regions ◽  
New Approach ◽  
Mathematical Algorithm ◽  
Intensity Index ◽  
Radar Imagery ◽  
Instability Indices

In this study, an investigation of a new thunderstorm intensity index (TSII) derived from lightning data is performed, along with its relationship to rain, wind, hail and waterspouts as well as instability indices (CAPE, LI, KI, and DLS). The study area is located in the northeastern Adriatic and includes various terrain types in a relatively small area (coastal, flatlands, hills and valleys, and mountain regions). The investigated period covers 11 years (2008–2018). The mathematical algorithm standing behind the TSII is based on the well-established methodology of lightning jump, allowing us to recognize areas where intensification in thunderstorms occurred. Our results suggest that these areas (with a positive TSII) experience significantly higher rain intensities and have higher total amounts of precipitation compared with areas where thunderstorms did not generate a TSII. Moreover, 76% of thunderstorm hail cases were associated with the presence of a TSII within a 15 km distance. The maximum reported wind speed also has higher values on a day with a TSII. Out of 27 waterspout events associated with lightning, 77% were related to a TSII. Due to the good spatial (3 km × 3 km) and high temporal (2 min) resolution of lightning data, the TSII can recognize even a local and short-lived intense system that is often misread by radars and satellites due to their inferior temporal resolution. The TSII is designed to be used as a climatological and diagnostic variable that could serve in lieu of more established data sources (e.g., station measurements and observations, radar imagery, etc.) if they are unavailable.

scholarly journals The Use of Odd and Even Class Wind Speed Time Series of Distribution Histogram to Estimate Weibull Parameters

2018 ◽  
Vol 7 (2) ◽  
pp. 139-150 ◽  
Author(s):  
Adekunlé Akim Salami ◽  
Ayité Sénah Akoda Ajavon ◽  
Mawugno Koffi Kodjo ◽  
Seydou Ouedraogo ◽  
Koffi-Sa Bédja
Keyword(s):  
Time Series ◽  
Wind Speed ◽  
Time Series Data ◽  
Empirical Method ◽  
Likelihood Method ◽  
Series Data ◽  
New Approach ◽  
Weibull Parameters ◽  
Distribution Histogram ◽  
Mean Wind Speed

In this article, we introduced a new approach based on graphical method (GPM), maximum likelihood method (MLM), energy pattern factor method (EPFM), empirical method of Justus (EMJ), empirical method of Lysen (EML) and moment method (MOM) using the even or odd classes of wind speed series distribution histogram with 1 m/s as bin size to estimate the Weibull parameters. This new approach is compared on the basis of the resulting mean wind speed and its standard deviation using seven reliable statistical indicators (RPE, RMSE, MAPE, MABE, R2, RRMSE and IA). The results indicate that this new approach is adequate to estimate Weibull parameters and can outperform GPM, MLM, EPF, EMJ, EML and MOM which uses all wind speed time series data collected for one period. The study has also found a linear relationship between the Weibull parameters K and C estimated by MLM, EPFM, EMJ, EML and MOM using odd or even class wind speed time series and those obtained by applying these methods to all class (both even and odd bins) wind speed time series. Another interesting feature of this approach is the data size reduction which eventually leads to a reduced processing time.Article History: Received February 16th 2018; Received in revised form May 5th 2018; Accepted May 27th 2018; Available onlineHow to Cite This Article: Salami, A.A., Ajavon, A.S.A., Kodjo, M.K. , Ouedraogo, S. and Bédja, K. (2018) The Use of Odd and Even Class Wind Speed Time Series of Distribution Histogram to Estimate Weibull Parameters. Int. Journal of Renewable Energy Development 7(2), 139-150.https://doi.org/10.14710/ijred.7.2.139-150

scholarly journals Methodology for Optimal Placement of Containers in Trains in Case of Cargo Operations Along the Route

2021 ◽  
Vol 19 (1) ◽  
pp. 174-193
Author(s):  
D. I. Kochneva ◽  
S. V. Siziy ◽  
Hao Chang
Keyword(s):  
Container Terminal ◽  
Container Terminals ◽  
Optimal Placement ◽  
Intermediate Point ◽  
Iterative Search ◽  
New Approach ◽  
Cargo Handling ◽  
Mathematical Algorithm ◽  
Passenger Traffic ◽  
Optimisation Methods

A new approach to organisation of container block trains is considered based on the principles of passenger traffic. The technology assumes container train’s traffic subject to the timetable with sale of cargo space in the train. The train is made up at the departure station and follows the established route with stops at intermediate container terminals or stations, where a container for which this station is designated as destination is removed and a new container is placed on the vacated place to be delivered to subsequent points of the route.The objective of this study is to develop a methodology for optimal placement of containers in a block train intended for en route cargo handling operations. The technique involves an iterative search for such an order of placement of packages so that containers assigned to each intermediate point are as close to each other as possible. The technique is an authors’ algorithm based on combinatorial optimisation methods.The implementation of the proposed algorithm makes it possible to reduce the excessive mileage of handlers and loaders at intermediate points and, consequently, to increase speed of cargo operations when rearranging containers, as well as to reduce operating costs of using the loading facilities of the container terminal.The proposed mathematical algorithm as compared to exhaustive search allows significantly reducing the number of iterations in search for a solution and can be implemented as software.

A New Approach to Generate Hospital Data Warehouse Schema

2016 ◽  
pp. 84-115 ◽  
Author(s):  
Nouha Arfaoui ◽  
Jalel Akaichi
Keyword(s):  
Decision Making ◽  
Data Warehouse ◽  
Information Exchange ◽  
Data Sources ◽  
Healthcare Industry ◽  
Schema Integration ◽  
Hospital Data ◽  
New Approach ◽  
Similar Elements ◽  
Existing Data

The healthcare industry generates huge amount of data underused for decision making needs because of the absence of specific design mastered by healthcare actors and the lack of collaboration and information exchange between the institutions. In this work, a new approach is proposed to design the schema of a Hospital Data Warehouse (HDW). It starts by generating the schemas of the Hospital Data Mart (HDM) one for each department taking into consideration the requirements of the healthcare staffs and the existing data sources. Then, it merges them to build the schema of HDW. The bottom-up approach is suitable because the healthcare departments are separately. To merge the schemas, a new schema integration methodology is used. It starts by extracting the similar elements of the schemas and the conflicts and presents them as mapping rules. Then, it transforms the rules into queries and applies them to merge the schemas.

scholarly journals A Software Architecture to Mimic a Ventricular Tachycardia in Intact Murine Hearts by Means of an All-Optical Platform

2019 ◽  
Vol 2 (1) ◽  
pp. 7 ◽  
Author(s):  
Francesco Giardini ◽  
Valentina Biasci ◽  
Marina Scardigli ◽  
Francesco S. Pavone ◽  
Gil Bub ◽  
...  
Keyword(s):  
Ventricular Tachycardia ◽  
Electrical Activity ◽  
Real Time ◽  
Temporal Resolution ◽  
Technical Note ◽  
High Temporal Resolution ◽  
Excitable Cells ◽  
New Approach ◽  
Cardiac Electrical Activity ◽  
All Optical

Optogenetics is an emerging method that uses light to manipulate electrical activity in excitable cells exploiting the interaction between light and light-sensitive depolarizing ion channels, such as channelrhodopsin-2 (ChR2). Initially used in the neuroscience, it has been adopted in cardiac research where the expression of ChR2 in cardiac preparations allows optical pacing, resynchronization and defibrillation. Recently, optogenetics has been leveraged to manipulate cardiac electrical activity in the intact heart in real-time. This new approach was applied to simulate a re-entrant circuit across the ventricle. In this technical note, we describe the development and the implementation of a new software package for real-time optogenetic intervention. The package consists of a single LabVIEW program that simultaneously captures images at very high frame rates and delivers precisely timed optogenetic stimuli based on the content of the images. The software implementation guarantees closed-loop optical manipulation at high temporal resolution by processing the raw data in workstation memory. We demonstrate that this strategy allows the simulation of a ventricular tachycardia with high stability and with a negligible loss of data with a temporal resolution of up to 1 ms.

scholarly journals Statistical dynamics of tropical wind in radiosonde data

2011 ◽  
Vol 11 (9) ◽  
pp. 4177-4189 ◽  
Author(s):  
T.-Y. Koh ◽  
Y. S. Djamil ◽  
C.-K. Teo
Keyword(s):  
Wind Speed ◽  
Shape Parameter ◽  
Radiosonde Data ◽  
Strong Wind ◽  
Malay Peninsula ◽  
New Approach ◽  
Statistical Dynamics ◽  
The Tropics ◽  
Scientific Questions ◽  
Global Datasets

Abstract. Weibull distributions were fitted to wind speed data from radiosonde stations in the global tropics. A statistical theory of independent wind contributions was proposed to partially explain the shape parameter k obtained over Malay Peninsula and the wider Equatorial Monsoon Zone. This statistical dynamical underpinning provides some justification for using empirical Weibull fits to derive wind speed thresholds for monitoring data quality. The regionally adapted thresholds retain more useful data than conventional ones defined from taking the regional mean plus three standard deviations. The new approach is shown to eliminate reports of atypically strong wind over Malay Peninsula which may have escaped detection in quality control of global datasets as the latter has assumed a larger spread of wind speed. New scientific questions are raised in the pursuit of statistical dynamical understanding of meteorological variables in the tropics.

Mapping surface soil moisture over wheat crops in southern Mediterranean regions using the backscattering coefficient and the interferometric coherence derived from Sentinel-1

2020 ◽  
Author(s):  
Nadia Ouaadi ◽  
Lionel Jarlan ◽  
Jamal Ezzahar ◽  
Saïd Khabba ◽  
Mehrez Zribi ◽  
...  
Keyword(s):  
Soil Moisture ◽  
Temporal Resolution ◽  
Surface Soil ◽  
Cloud Model ◽  
Microwave Remote Sensing ◽  
Radar Data ◽  
Optical Data ◽  
Surface Soil Moisture ◽  
Backscattering Coefficient ◽  
New Approach

<p>High spatial and temporal resolution products of Sentinel-1 are used for surface soil moisture (SSM) mapping over wheat fields in semi-arid areas. Within these regions, monitoring the water-use is a critical aspect for optimizing the management of the limited water resources via irrigation monitoring. SSM is one of the principal quantities affecting microwave remote sensing. This sensitivity has been exploited to estimate SSM from radar data, which has the advantages of providing data independent of illumination and weather conditions. In addition, with the use of Sentinel-1 products, the spatial and temporal resolution is greatly improved. Within this context, the main objective of this work is estimate SSM over wheat fields using an approach based on the use of C-band Sentinel-1 radar data only. Over the study site, field measurement are collected during 2016-2017 and 2017-2018 growing seasons over two fields of winter wheat with drip irrigation located in the Haouz plain in the center of Morocco. Data of other sites in Morocco and Tunisia are taken for validation purposes. The validation database contains a total number of 20 plots divided between irrigated and rainfed wheat plots. Two different information extracted from Sentinel-1 products are used: the backscattering coefficient and the interferometric coherence. A total number of 408 GRD and 419 SLC images were processed for computing the backscattering coefficient and the interferometric coherence, respectively. The analysis of Sentinel-1 time series over the study site show that coherence is sensitive to the development of wheat, while the backscatter coefficient is widely linked to changes in surface soil moisture. Later on, the Water Cloud Model coupled with the Oh et al, 1992 model were used for better understand the backscattering mechanism of wheat canopies. The coupled model is calibrated and validated over the study site and it proved to goodly enough reproduce the Sentinel-1 backscatter with RMSE ranging from 1.5 to 2.52 dB for VV and VH using biomass as a descriptor of wheat. On the other side, the analysis show that coherence is well correlated to biomass. Thus, the calibrated model is used in an inversion algorithm to retrieve SSM using the Sentinel-1 backscatter and coherence as inputs. The results of inversion show that the proposed new approach is able to retrieve the surface soil moisture at 35.2° for VV, with R=0.82, RMSE=0.05m<sup>3/</sup>m<sup>3 </sup>and no bias. Using the validation database of Morocco and Tunisia, R is always greater than 0.7 and RMSE and bias are less than 0.008 m<sup>3/</sup>m<sup>3</sup> and 0.03 m<sup>3/</sup>m<sup>3</sup>, respectively even that the incidence angle is higher (40°). In order to assess its quality, the approach is compared to four SSM retrieval methods that use radar and optical data in empirical and semi-empirical approaches. Results indicate that the proposed approach shows an improvement of SSM retrieval between 17% and 42% compared to other methods. Finally, the validated new approach is used for SSM mapping, with a spatial resolution of 10*10 m, over irrigated perimeters of wheat in Morocco.</p>

Sign in / Sign up

Export Citation Format

Share Document