Infrasound signals from a ground-truth source and implications from atmospheric models: ARIANE engine tests in Southern Germany revisited

Author(s):  
Karl Koch ◽  
Christoph Pilger

<p>Over the past two decades the German Aerospace Center (DLR) facility near Heilbronn, Germany, has conducted a considerable number of tests of the ARIANE-5 main engine. Infrasound signals from many of these tests (~40%) have been observed at IMS station IS26 at a distance of about 320 km in an easterly direction (99° east-southeast from North). Due to the prevailing weather pattern in Central Europe, nearly all detected tests occurred during the winter months from October to April, when the stratospheric wind points in an eastern direction, while it reverses during the summer season. Except for a single event in May 2012, the summer months (May through September) did not yield any infrasound signal detections from the engine tests. On the other hand, not all tests conducted in winter are observed either, while detection in the spring and fall equinox months of April and October must be considered to occur incidentally.<br> <br>The large database of about 160 engine tests enables us to assess how well propagation modelling based on a standard atmospheric specification such as the ECMWF forecast model conforms with observed detections and non-detections.  While reversal of the stratospheric wind pattern in the summer season eliminates the stratospheric duct towards the eastern direction, the case of non-detections in the winter season may be of a more subtle nature. Besides increases in background noise levels due to heavy winds at the station, the fine structure of the stratospheric duct in the atmospheric model should determine the detection capability at IS26, which could be located inside or outside a shadow zone at a specific time. Ultimately, the standard atmospheric model used may not be an accurate description of the atmosphere in such cases either. This work on a controlled ground truth infrasound source will thus increase our understanding on the relationship between infrasound detection capabilities and atmospheric specifications over the seasons.</p>

2021 ◽  
Author(s):  
Karl Koch ◽  
Christoph Pilger

<p>From the more than 160 tests of the ARIANE-5 main engine carried out by the German Aerospace Center (DLR) facility near Heilbronn, Germany, a large overall portion was detected at IMS infrasound station IS26 in the Bavarian forest. Located at a distance of about 320 km in an easterly direction (99° east-southeast from North) these observations were mostly made in the winter season between October and April with a detection rate of more than 70% , as stratospheric winds favor infrasound propagating through the atmosphere within the stratospheric duct. Only two exceptions were found for the summer season when stratospheric ducting is not predicted neither by climatologies nor the applied weather prediction models, due to a reversal of the middle atmosphere wind pattern.</p><p>Numerical weather prediction models for summer and winter seasons, or times with detections or non-detections were compared. It is then found that these models differ significantly in the sound speed profiles producing either a strong stratospheric duct for altitudes between 30 and 60 km in the case of detection, i.e. in winter months – or a lack thereof inhibiting regional sound propagation in summer months. It is of course reflected by the effective sound speed ratio, mostly exceeding a value of 1 for detections and less than 1 for non-detections. A significant portion of profiles representing non-detections, however, exhibit a sound speed profile that should enable infrasound signal observations. These cases are analyzed in detail to identify which fine structures within the sound speed profiles could explain the lack of observations.</p>


MAUSAM ◽  
2021 ◽  
Vol 43 (2) ◽  
pp. 195-198
Author(s):  
V.S. RAMACHANDRAN ◽  
N. M. MURALI

Statistical analysis was carried out between seasonal milk yield and some of the derived climatic variables at a semi-arid tropical locality in Bangalore. The study revealed that the milk yields varied from the highest (9, 3 lit/cow/day) in summer season to the lowest (8, 5 lit/cow/day) in winter season and almost the same in both the monsoon season (8, 7 and 8, 5 lit/cow/day during southwest and northeast monsoon seasons). It was envisaged that the climatic components like wind chill index had negative effect while wetness index and photo-thermal heat units had both positive (summer and winter seasons) and negative (two monsoon seasons) influences on seasonal milk yields.


Author(s):  
M.I. Rosas-Jaco ◽  
S.X. Almeraya-Quintero ◽  
L.G. Guajardo-Hernández

Objective: Tourism has become the main engine of economic, social and environmental development in several countries, so promoting tourism awareness among tourists and the local population should be a priority. The present study aims to suggest a status of the research carried out on the topic of tourism awareness. Design / methodology / approach: The type of analysis is through a retrospective and exploratory bibliometric study. The analysis materials were scientific articles and a training manual published between 2000 and 2020, registered by Scopus, Emerald insight and Dialnet, using “tourism awareness” as the keyword. Results: When considering the three senses in which tourism awareness ought to operate, it is concluded that studies are more focused on the relationship and contact of the host community with the tourist. It is observed that four out of six articles in this sense consider that education, training, and government policies around tourism awareness should be developed in a better way in the destinations, in order to be an element that contributes to the development of communities and reduces poverty in developing countries. Study limitations / implications: It is considered a limitation not to include thesis dissertations. Findings / conclusions: It is necessary to make visible the importance of tourism awareness as a local development strategy for communities, in addition to including tourism awareness on the part of tourists.


2019 ◽  
Vol 25 (1) ◽  
Author(s):  
ADITYA NARAYAN

The present investigation deals with the prevalence of infection of cestode, Pseudoinverta oraiensis19 parasitizing Clarias batrachus from Bundelkhand Region (U.P.) India. The studies were recorded from different sampling stations of Bundelkhand region of Uttar Pradesh. For this study 360 fresh water fish, Clarias batrachus were examined. The incidence of infection, monsoon season (17.50%) followed by winter season (20.00%) whereas high in summer season (30.00%).


Author(s):  
Phạm Hồng Sơn ◽  
Phạm Hồng Kỳ ◽  
Nguyễn Thị Lan Hương ◽  
Phạm Thị Hồng Hà

. Using the method of shifting assay of standardized indirect agglutination (SSIA), the prevalence of Newcastle disease viruses (NDV) and infectious bursal disease viruses (IBDV) in chickens reared in several districts of Thua Thien Hue province in the Spring-Summer and Fall-Winter seasons was determined. In the Spring-Summer season of 2011, about 22.3% of the chickens were infected with NDV, in which A Luoi  accounted for the highest percentage of 25% of the infected chickens and Huong Thuy  the lowest  of 18.2%. Meanwhile, 36% of the same chickens were infected with IBDV, with the highest percentage (46.66%) also in A Luoi and the lowest (30.3%) also in Huong Thuy. The intensity of NDV infection in the Spring-Summer season in A Luoi and Phu Vang was highest (GMT = 1.45), and in Huong Thuy lowest (GMT = 1.31). In addition, in the Fall-Winter season, about 46% of the chickens were infected with NDV and 46.3% with IBDV in Huong Thuy and Phu Vang – two neighbouring districts of Hue City, in which NDV was detected in 54.4% of the chickens in Huong Thuy and 33.9% in Phu Vang. In contrast, IBDV was detected in 41.9% and 52.7% of the chickens respectively in the two districts. The infection was not inter-dependent. Methodically, although the differences in the infection rates were insignificant with the accuracy of 95%, faecal samples showed higher sensitivity in SSIA analyses for both cases of NDV and IBDV infection in comparision with mouth exudates. By SSIA method, results could be read clearly with unaided eyes for a long time after the performance, and it was also proven applicable for cases of haemagglutinating viruses if proper treatments for depletion of animal RBCs’ surface agglutinins could be applied.


2021 ◽  
Vol 13 (10) ◽  
pp. 1966
Author(s):  
Christopher W Smith ◽  
Santosh K Panda ◽  
Uma S Bhatt ◽  
Franz J Meyer ◽  
Anushree Badola ◽  
...  

In recent years, there have been rapid improvements in both remote sensing methods and satellite image availability that have the potential to massively improve burn severity assessments of the Alaskan boreal forest. In this study, we utilized recent pre- and post-fire Sentinel-2 satellite imagery of the 2019 Nugget Creek and Shovel Creek burn scars located in Interior Alaska to both assess burn severity across the burn scars and test the effectiveness of several remote sensing methods for generating accurate map products: Normalized Difference Vegetation Index (NDVI), Normalized Burn Ratio (NBR), and Random Forest (RF) and Support Vector Machine (SVM) supervised classification. We used 52 Composite Burn Index (CBI) plots from the Shovel Creek burn scar and 28 from the Nugget Creek burn scar for training classifiers and product validation. For the Shovel Creek burn scar, the RF and SVM machine learning (ML) classification methods outperformed the traditional spectral indices that use linear regression to separate burn severity classes (RF and SVM accuracy, 83.33%, versus NBR accuracy, 73.08%). However, for the Nugget Creek burn scar, the NDVI product (accuracy: 96%) outperformed the other indices and ML classifiers. In this study, we demonstrated that when sufficient ground truth data is available, the ML classifiers can be very effective for reliable mapping of burn severity in the Alaskan boreal forest. Since the performance of ML classifiers are dependent on the quantity of ground truth data, when sufficient ground truth data is available, the ML classification methods would be better at assessing burn severity, whereas with limited ground truth data the traditional spectral indices would be better suited. We also looked at the relationship between burn severity, fuel type, and topography (aspect and slope) and found that the relationship is site-dependent.


2021 ◽  
Author(s):  
Ali Abdolali ◽  
Andre van der Westhuysen ◽  
Zaizhong Ma ◽  
Avichal Mehra ◽  
Aron Roland ◽  
...  

AbstractVarious uncertainties exist in a hindcast due to the inabilities of numerical models to resolve all the complicated atmosphere-sea interactions, and the lack of certain ground truth observations. Here, a comprehensive analysis of an atmospheric model performance in hindcast mode (Hurricane Weather and Research Forecasting model—HWRF) and its 40 ensembles during severe events is conducted, evaluating the model accuracy and uncertainty for hurricane track parameters, and wind speed collected along satellite altimeter tracks and at stationary source point observations. Subsequently, the downstream spectral wave model WAVEWATCH III is forced by two sets of wind field data, each includes 40 members. The first ones are randomly extracted from original HWRF simulations and the second ones are based on spread of best track parameters. The atmospheric model spread and wave model error along satellite altimeters tracks and at stationary source point observations are estimated. The study on Hurricane Irma reveals that wind and wave observations during this extreme event are within ensemble spreads. While both Models have wide spreads over areas with landmass, maximum uncertainty in the atmospheric model is at hurricane eye in contrast to the wave model.


Plants ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 1591
Author(s):  
Patrícia Carvalho da Silva ◽  
Walter Quadros Ribeiro Junior ◽  
Maria Lucrecia Gerosa Ramos ◽  
Sonia Maria Costa Celestino ◽  
Alberto do Nascimento Silva ◽  
...  

Quinoa stands out as an excellent crop in the Cerrado region for cultivation in the off-season or irrigated winter season. Here, we tested the effects of different water regimes on the agronomic characteristics, physiology, and grain quality of different elite quinoa genotypes under field conditions. The experiment was conducted under field conditions at Embrapa Cerrados (Planaltina, DF, Brazil). The experimental design was in randomized blocks, in a split-plot scheme, with four replications. The plots were composed of 18 quinoa genotypes and modified BRS Piabiru (the currently used genotype), and the split-plots were divided into 4 different water regimes. The following variables were evaluated: productivity and productivity per unit of applied water (PUAA), plant height, flavonoids, anthocyanins, gas exchange, chlorophyll, leaf proline, and relative water content. Our results showed that water regimes between 309 and 389 mm can be recommended for quinoa in the Cerrado region. CPAC6 and CPAC13 presented the highest yield and PUAA under high and intermediate WRs, and hence were the most suitable for winter growth under irrigation. CPAC17 is most suitable for off-season growth under rainfed conditions, as it presented the highest PUAA under the low WRs (247 and 150). CPAC9 stood out in terms of accumulation of flavonoids and anthocyanins in all WRs. Physiological analyses revealed different responses of the genotypes to water restriction, together with symptoms of stress under lower water regimes. Our study reinforces the importance of detailed analyses of the relationship between productivity, physiology, and water use when choosing genotypes for planting and harvest in different seasons.


Author(s):  
Woosub Jung ◽  
Amanda Watson ◽  
Scott Kuehn ◽  
Erik Korem ◽  
Ken Koltermann ◽  
...  

For the past several decades, machine learning has played an important role in sports science with regard to player performance and result prediction. However, it is still challenging to quantify team-level game performance because there is no strong ground truth. Thus, a team cannot receive feedback in a standardized way. The aim of this study was twofold. First, we designed a metric called LAX-Score to quantify a collegiate lacrosse team's athletic performance. Next, we explored the relationship between our proposed metric and practice sensing features for performance enhancement. To derive the metric, we utilized feature selection and weighted regression. Then, the proposed metric was statistically validated on over 700 games from the last three seasons of NCAA Division I women's lacrosse. We also explored our biometric sensing dataset obtained from a collegiate team's athletes over the course of a season. We then identified the practice features that are most correlated with high-performance games. Our results indicate that LAX-Score provides insight into athletic performance beyond wins and losses. Moreover, though COVID-19 has stalled implementation, the collegiate team studied applied our feature outcomes to their practices, and the initial results look promising with regard to better performance.


2020 ◽  
Vol 27 (4) ◽  
pp. 114-120
Author(s):  
Suaad danok ◽  
Kamal Twfek ◽  
Esraa Mansour

This research depends on carrying out an applied and numerical analysis for capability to utilize winds turbines which considered as means of renewable and friendly energy to environment, and how to make use of this technology to generate electric energy in Kirkuk city. Where it was studied shifting kinetic energy of winds into mechanic energy and has been accomplishes install a horizontal-turbine in one of work sites in Kirkuk city of (16m) height of the ground level. It has tri-blades of (400W) power. It has been connected to an electric system supply designed and manufacture during the research period. In order to measure the voltage-difference and electric current consequently to measure the power and energy produced from the wind turbine and changed according to the wind speed alteration. Gauge records for two time seasons are taken by using the technology-programming of delicate controller in simultaneous work with meteorological system, so that it can set data-principle to be analyzed by using (MATLAB) program to find and check theoretical generated power compared with practical results and find the range of validity to generate the sufficient energy for domestic consumption. The results shows that summer season is better than winter season in using wind turbine in Kirkuk city. As the monthly energy rate produce during summer season has emerged to ten-time than monthly energy rate produced during winter season.


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