ASSESSING THE IMPACT OF THE SLOPES ON RUNWAY DRAINAGE CAPACITY BASED ON WHEEL/PATH SURFACE ADHESION CONDITIONS

Aircraft braking distance is dependent on the friction between the main gear tires and runway pavement surface.Pavement texture, which is divided into macrotexture and micro-texture, has a noticeable effect upon friction, especially when the surface is wet. A risk analysis framework is developed to study the effects of longitudinal and transverse slopes on the aircraft braking distance in wet runway conditions and their influences on the probability of landing overrun accidents.This framework is operating under various water-film thicknesses, Maximum Landing Weights (MLW), and touchdown speed probability distributions for an acceptable range of longitudinal/transverse slopes and pavement texture depths.A simulator code is developed that initially computes the existing water-film thickness, as the result of intense precipitation,under aircraft main gear (depend on aircraft category) and then applies this variable as one of the main inputs to the aircraft braking distance computation. According to the obtained results, longitudinal gradient does not have a significant effect on the existing water depth on the surface although it affects the flow path length. Furthermore, 1% to 1.5% transverse slope causes rapid drainage of water from the runway surface and considerably decreases the probability of runway excursion accidents.

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Asteroid and Comet Impact Speeds upon Mars: Significance for Panspermia and the Supply of Organics

International Astronomical Union Colloquium ◽

10.1017/s0252921100014718 ◽

1997 ◽

Vol 161 ◽

pp. 197-201 ◽

Cited By ~ 1

Author(s):

Duncan Steel

Keyword(s):

Probability Distributions ◽

Regions Of Interest ◽

Significant Fraction ◽

Organic Chemicals ◽

Impact Speed ◽

The Mean ◽

The Impact

AbstractWhilst lithopanspermia depends upon massive impacts occurring at a speed above some limit, the intact delivery of organic chemicals or other volatiles to a planet requires the impact speed to be below some other limit such that a significant fraction of that material escapes destruction. Thus the two opposite ends of the impact speed distributions are the regions of interest in the bioastronomical context, whereas much modelling work on impacts delivers, or makes use of, only the mean speed. Here the probability distributions of impact speeds upon Mars are calculated for (i) the orbital distribution of known asteroids; and (ii) the expected distribution of near-parabolic cometary orbits. It is found that cometary impacts are far more likely to eject rocks from Mars (over 99 percent of the cometary impacts are at speeds above 20 km/sec, but at most 5 percent of the asteroidal impacts); paradoxically, the objects impacting at speeds low enough to make organic/volatile survival possible (the asteroids) are those which are depleted in such species.

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Development of the Circular Bioeconomy: Drivers and Indicators

Sustainability ◽

10.3390/su13010413 ◽

2021 ◽

Vol 13 (1) ◽

pp. 413

Author(s):

Maximilian Kardung ◽

Kutay Cingiz ◽

Ortwin Costenoble ◽

Roel Delahaye ◽

Wim Heijman ◽

...

Keyword(s):

Circular Economy ◽

Food Production ◽

Conceptual Analysis ◽

Green Economy ◽

Political Agenda ◽

Analysis Framework ◽

Stakeholder Consultation ◽

Time Period ◽

The Impact ◽

The Eu

The EU’s 2018 Bioeconomy Strategy Update and the European Green Deal recently confirmed that the bioeconomy is high on the political agenda in Europe. Here, we propose a conceptual analysis framework for quantifying and analyzing the development of the EU bioeconomy. The bioeconomy has several related concepts (e.g., bio-based economy, green economy, and circular economy) and there are clear synergies between these concepts, especially between the bioeconomy and circular economy concepts. Analyzing the driving factors provides important information for monitoring activities. We first derive the scope of the bioeconomy framework in terms of bioeconomy sectors and products to be involved, the needed geographical coverage and resolution, and time period. Furthermore, we outline a set of indicators linked to the objectives of the EU’s bioeconomy strategy. In our framework, measuring developments will, in particular, focus on the bio-based sectors within the bioeconomy as biomass and food production is already monitored. The selected indicators commit to the EU Bioeconomy Strategy objectives and conform with findings from previous studies and stakeholder consultation. Additionally, several new indicators have been suggested and they are related to measuring the impact of changes in supply, demand drivers, resource availability, and policies on sustainability goals.

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Statistical Analysis and Machine Learning Prediction of Fog-Caused Low-Visibility Events at A-8 Motor-Road in Spain

Atmosphere ◽

10.3390/atmos12060679 ◽

2021 ◽

Vol 12 (6) ◽

pp. 679

Author(s):

Sara Cornejo-Bueno ◽

David Casillas-Pérez ◽

Laura Cornejo-Bueno ◽

Mihaela I. Chidean ◽

Antonio J. Caamaño ◽

...

Keyword(s):

Statistical Analysis ◽

Probability Distributions ◽

Pearson Correlation ◽

Likelihood Method ◽

Neural Network Approach ◽

Event Duration ◽

Full Characterization ◽

Low Visibility ◽

Learning Machine ◽

The Impact

This work presents a full statistical analysis and accurate prediction of low-visibility events due to fog, at the A-8 motor-road in Mondoñedo (Galicia, Spain). The present analysis covers two years of study, considering visibility time series and exogenous variables collected in the zone affected the most by extreme low-visibility events. This paper has then a two-fold objective: first, we carry out a statistical analysis for estimating the fittest probability distributions to the fog event duration, using the Maximum Likelihood method and an alternative method known as the L-moments method. This statistical study allows association of the low-visibility depth with the event duration, showing a clear relationship, which can be modeled with distributions for extremes such as Generalized Extreme Value and Generalized Pareto distributions. Second, we apply a neural network approach, trained by means of the ELM (Extreme Learning Machine) algorithm, to predict the occurrence of low-visibility events due to fog, from atmospheric predictive variables. This study provides a full characterization of fog events at this motor-road, in which orographic fog is predominant, causing important traffic problems during all year. We also show how the ELM approach is able to obtain highly accurate low-visibility events predictions, with a Pearson correlation coefficient of 0.8, within a half-hour time horizon, enough to initialize some protocols aiming at reducing the impact of these extreme events in the traffic of the A-8 motor road.

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Nitrate transport in the chalk vadose zone in in Picardy (France)

Geological Society London Special Publications ◽

10.1144/sp517-2020-164 ◽

2021 ◽

pp. SP517-2020-164

Author(s):

N. Surdyk ◽

L. Gourcy ◽

V. Bault ◽

N. Baran

Keyword(s):

Groundwater Quality ◽

Vadose Zone ◽

Nitrate Concentration ◽

Agricultural Practices ◽

Nitrate Transport ◽

Transport Time ◽

Major Question ◽

Noticeable Effect ◽

Fertiliser Application ◽

The Impact

AbstractSince the 1980s, nitrate has been shown to be present in soils and the vadose zone of various types of geological materials years after fertiliser application. In chalk where the vadose zone is thick, nitrate storage can be considerable and its transport time toward groundwater can be lengthy.In this context, evaluation of the impact of changes in agricultural practices on groundwater quality remains a major question. Improvement of groundwater quality can in certain cases be greatly delayed after the implementation of environmental agricultural practices.The principal objective of this study is to improve our knowledge of when changes in agricultural practices will have a noticeable effect on groundwater quality.To meet this objective, nitrate concentration profiles were performed in agricultural plots in Picardy (France). A crop marker event was used to calculate the transport velocity of water and associated solutes. This method is useful when other tracers (as tritium or chlorine) cannot be used. Estimated velocities range from 0.51 to 0.54 m/year; these values are similar to those described in similar chalk aquifers.

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Pengaruh Kedalaman Keprasan Tebu dengan Menggunakan Mesin Kepras Traktor Roda Dua Terhadap Kualitas Keprasan dan Pertumbuhan Tunas

Jurnal Ilmiah Mahasiswa Pertanian ◽

10.17969/jimfp.v1i1.1361 ◽

2016 ◽

Vol 1 (1) ◽

pp. 995-1001

Author(s):

Arzal Bili ◽

Syafriandi Syafriandi ◽

Mustaqimah Mustaqimah

Keyword(s):

Sugar Cane ◽

Test Results ◽

Noticeable Effect ◽

The Impact ◽

Tractor Engine

Tebu kepras adalah menumbuhkan kembali bekas tebu yang telah ditebang. Keprasan tebu bertujuan untuk memperbaiki pertumbuhan tebu supaya tunas yang keluar tidak mengambang diatas permukaan tanah. Tujuan dari penelitian ini untuk mengetahui pengaruh kedalaman keprasan tebu dengan menggunakan mesin kepras traktor roda dua terhadap kualitas keprasan dan pertumbuhan tunas. Hasil uji F analisis sidik ragam menyatakan kedalaman keprasan tebu tidak memiliki pengaruh nyata terhadap kualitas keprasan, namun berpengaruh terhadap pertumbuhan yaitu berpengaruh terhadap diameter batang umur 21 HSK dan umur 28 HSK. Potongan utuh yang paling banyak dijumpai pada kedalaman keprasan 6-9 cm, dan potongan pecah banyak dijumpai pada kedalaman 0-3 cm, sedangkan tunggul yang terbongkar banyak dijumpai pada kedalaman 3-6 cm.The cutting of sugarcane is regrow trace sugar cane that has been cut down. The cutting of sugarcane aim to process growth of sugarcane which shoots out of floating off the ground. The purpose of this study to determine the influence of the depth cutting of sugar cane using a tractor engine two wheels on the quality of cutting and growth buds. The test results were famous analysis of fingerprint range of express the depth of cuts in sugar cane has no noticeable effect on the quality of cutting, but the effect on the growth of the impact on the diameter of the age of 21 HSK and the age of 28 HSK. The cutting intact the most prevalent at a depth of cutting 6-9 cm, and broke out lots of found at a depth of 0- 3 cm, while the uncovered a lot of found at a depth of 3-6 cm.

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POLA KONSENTRASI SPASIAL INDUSTRI KECIL MENENGAH DI PROVINSI NUSA TENGGARA BARAT

GANEC SWARA ◽

10.35327/gara.v15i1.184 ◽

2021 ◽

Vol 15 (1) ◽

pp. 858

Author(s):

CHANDRADITYA BAGASKARA ◽

PUTU KARISMAWAN ◽

FIRMANSYAH FIRMANSYAH

Keyword(s):

Concentration Ratio ◽

Production Cost ◽

Location Theory ◽

Ratio Analysis ◽

Analysis Framework ◽

Economic Activities ◽

Systematic Analysis ◽

Power Sources ◽

The Right ◽

The Impact

Location Theory gives systematic analysis framework of selecting location of economic adn social activities. Chosing of the right location thrifts reduce the transportation and production cost that drives efficient in production and marketing. The impact of efficiency is the higest profit and concentration of economic activities. There are many factor afecting the concentration of economic activities, such as wages, man power sources and productivity. Based on Concentration Ratio analysis that Small-medium industries cosentrated in Mataram City and Central Lombok distric. Based on concentration Index of Man power shows that the concentration of man power are in Sumbawa district, North Lombok, Central Lombok, Bima City, Bima district and West Lombok district. Based on those result that concentration spatial of Small-Medium Industries in each district of West Nusa Tenggara are not equal . Based on Regresioan analysis with Randomeffect Model that concentration of small-medium industries in West Nusa Tenggara siginificanly corelated with amount of man power and productivity, neither than wages.

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Weather Impact on Airport Performance

Aerospace ◽

10.3390/aerospace5040109 ◽

2018 ◽

Vol 5 (4) ◽

pp. 109 ◽

Cited By ~ 4

Author(s):

Michael Schultz ◽

Sandro Lorenz ◽

Reinhard Schmitz ◽

Luis Delgado

Keyword(s):

Traffic Management ◽

Probability Distributions ◽

Weather Conditions ◽

Air Traffic ◽

Weather Data ◽

Data Set ◽

Airport Capacity ◽

Weather Events ◽

The Individual ◽

The Impact

Weather events have a significant impact on airport performance and cause delayed operations if the airport capacity is constrained. We provide quantification of the individual airport performance with regards to an aggregated weather-performance metric. Specific weather phenomena are categorized by the air traffic management airport performance weather algorithm, which aims to quantify weather conditions at airports based on aviation routine meteorological reports. Our results are computed from a data set of 20.5 million European flights of 2013 and local weather data. A methodology is presented to evaluate the impact of weather events on the airport performance and to select the appropriate threshold for significant weather conditions. To provide an efficient method to capture the impact of weather, we modelled departing and arrival delays with probability distributions, which depend on airport size and meteorological impacts. These derived airport performance scores could be used in comprehensive air traffic network simulations to evaluate the network impact caused by weather induced local performance deterioration.

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Research on the Prediction of Impact Sound Insulation to a Homogeneous Wall

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.744-746.1593 ◽

2015 ◽

Vol 744-746 ◽

pp. 1593-1596

Author(s):

Shang You Wei ◽

Xian Feng Huang ◽

Zhi Xiang Zhuang ◽

Jun Xin Lan

Keyword(s):

Energy Analysis ◽

Sound Transmission ◽

Sound Insulation ◽

Statistical Energy Analysis ◽

Analysis Framework ◽

Mechanism Of Impact ◽

Sound Reduction ◽

The Impact ◽

Insulating Properties ◽

Reduction Index

In this paper, a theoretical model to evaluate impact sound transmission through a homogeneous wall is proposed. The model which is based on the Statistical Energy Analysis framework exhibits a system with room-wall-room. For the purpose to explore the mechanism of impact sound transmission through a wall, the impact sound reduction index between two rooms are predicted. Meanwhile, the variation of impact sound reduction index with the walls properties are also taken into account. The results reveal that the density, elastic modulus and thickness of a homogeneous wall have diverse effects on its impact sound insulation and can be chosen adequately to achieve ideal insulation values.It provides an approach to optimize impact sound insulating properties of the walls.

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Framework for evaluating risk of limited sight distance for permitted left-turn movements: case study

Canadian Journal of Civil Engineering ◽

10.1139/cjce-2015-0498 ◽

2016 ◽

Vol 43 (4) ◽

pp. 369-377 ◽

Cited By ~ 11

Author(s):

Ahmed Osama ◽

Tarek Sayed ◽

Said Easa

Keyword(s):

Reliability Analysis ◽

Probability Distributions ◽

Video Data ◽

Analysis Framework ◽

Left Turn ◽

Sight Distance ◽

Time Gap ◽

Input Variables ◽

The City

A reliability analysis framework is used to evaluate the risk of limited sight distance for permitted left-turn movements due to the presence of opposing left-turn vehicles. Two signalized intersection approaches in the city of Surrey were used as case studies for the framework. Geometric and traffic video data was collected and analyzed using a computer vision tool to extract the input variables probability distributions. The data was used in the reliability analysis where first-order and Importance Sampling methods were performed. The analysis showed that the probability of non-compliance was considerable at one approach due to its large left-turn lane offset. The analysis also showed that the probability of non-compliance increased substantially when the obstacle vehicle was a bus rather than a passenger car. Moreover, the time gap had a higher impact on the probability of non-compliance compared to speed. Strategies were suggested to overcome the high probability of non-compliance.

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New Methods and Critical Aspects in Bayesian Mathematics for 14C Calibration

Radiocarbon ◽

10.1017/s0033822200038236 ◽

2001 ◽

Vol 43 (2A) ◽

pp. 373-380 ◽

Cited By ~ 21

Author(s):

Peter Steier ◽

Werner Rom ◽

Stephan Puchegger

Keyword(s):

Iron Age ◽

Probability Distributions ◽

Bayes Theorem ◽

General Technique ◽

Realistic Case ◽

Prior Probabilities ◽

New Methods ◽

Mathematical Probability ◽

The Impact ◽

Critical Aspects

The probabilistic radiocarbon calibration approach, which largely has replaced the intercept method in 14C dating, is based on the so-called Bayes' theorem (Bayes 1763). Besides single-sample calibration, Bayesian mathematics also supplies tools for combining 14C results of many samples with independent archaeological information such as typology or stratigraphy (Buck et al. 1996). However, specific assumptions in the “prior probabilities”, used to transform the archaeological information into mathematical probability distributions, may bias the results (Steier and Rom 2000). A general technique for guarding against such a bias is “sensitivity analysis”, in which a range of possible prior probabilities is tested. Only results that prove robust in this analysis should be used. We demonstrate the impact of this method for an assumed, yet realistic case of stratigraphically ordered samples from the Hallstatt period, i.e. the Early Iron Age in Central Europe.

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