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2022 ◽  
pp. 115-126
Author(s):  
Surabhi Singh ◽  
José Duarte Santos

AI-powered technologies allow online B2B companies to serve their customers with accurate and relevant information, 24/7. For example, they experience an increase in requests for information from customers on such aspects as product availability, features, or other services. The chapter aims to explore artificial intelligence in B2B business. The study employed qualitative research, and the data was collected through a focus group for data collection. An AI-powered chatbot enhanced with natural language processing and understanding conversationally-worded requests could instantaneously provide this information without a human representative. This is vital as the added uncertainty around the pandemic means business customers seek real answers and ways to adapt and fast. The findings suggest the critical success factors of AI-driven CRM in B2B markets. The limitations of the study include the data collection being restricted to one B2B company. The implications are that further study can be extended for exploring AI-based CRM in B2B markets.


2021 ◽  
Vol 14 (7) ◽  
pp. 5179-5197
Author(s):  
Scott P. Seymour ◽  
Matthew R. Johnson

Abstract. Field measurement of flare emissions in turbulent flare plumes is an important and complex challenge. Incomplete combustion from these processes results in emissions of black carbon, unburnt fuels (methane), CO2, and other pollutants. Many field measurement approaches necessarily assume that combustion species are spatially and/or temporally correlated in the plume, such that simple species ratios can be used to close a carbon balance to calculate species emission factors and flare conversion efficiency. This study examines the veracity of this assumption and the associated implications for measurement uncertainty. A novel tunable diode laser absorption spectroscopy (TDLAS) system is used to measure the correlation between H2O and black carbon (BC) volume fractions in the plumes of a vertical, turbulent, non-premixed, buoyancy-driven lab-scale gas flare. Experiments reveal that instantaneous, path-averaged concentrations of BC and H2O can vary independently and are not necessarily well correlated over short time intervals. The scatter in the BC/H2O ratio along a path through the plume was well beyond that which could be attributed to measurement uncertainty and was asymmetrically distributed about the mean. Consistent with previous field observations, this positive skewness toward higher BC/H2O ratios implies short, localized, and infrequent bursts of high BC production that are not well correlated with H2O. This demonstrates that the common assumption of fixed species ratios is not universally valid, and measurements based on limited samples, short sampling times, and/or limited spatial coverage of the plume could be subject to potentially large added uncertainty. For BC emission measurements, the positive skewness of the BC/H2O ratio also suggests that results from small numbers of samples are more likely to be biased low. However, a bootstrap analysis of the results shows how these issues can be avoided with sufficient sample size and provides initial guidance for creating sampling protocols for future field measurements using analogous path-averaged techniques.


2021 ◽  
Vol 81 (7) ◽  
Author(s):  
Martin Beneke ◽  
Philipp Böer ◽  
Panagiotis Rigatos ◽  
K. Keri Vos

AbstractMotivated by the first search for the rare charged-current B decay to four leptons, $$\ell \bar{\nu }_\ell \ell ^{(\prime )} \bar{\ell }^{(\prime )}$$ ℓ ν ¯ ℓ ℓ ( ′ ) ℓ ¯ ( ′ ) , we calculate the decay amplitude with factorization methods. We obtain the $$B\rightarrow \gamma ^*$$ B → γ ∗ form factors, which depend on the invariant masses of the two lepton pairs, at leading power in an expansion in $$\Lambda _\mathrm{QCD}/m_b$$ Λ QCD / m b to next-to-leading order in $$\alpha _s$$ α s , and at $$\mathcal {O}(\alpha _s^0)$$ O ( α s 0 ) at next-to-leading power. Our calculations predict branching fractions of a few times $$10^{-8}$$ 10 - 8 in the $$\ell ^{(\prime )} \bar{\ell }^{(\prime )}$$ ℓ ( ′ ) ℓ ¯ ( ′ ) mass-squared bin up to $$q^2=1~$$ q 2 = 1 GeV$$^2$$ 2 with $$n_+q>3~$$ n + q > 3 GeV. The branching fraction rapidly drops with increasing $$q^2$$ q 2 . An important further motivation for this investigation has been to explore the sensitivity of the decay rate to the inverse moment $$\lambda _B$$ λ B of the leading-twist B meson light-cone distribution amplitude. We find that in the small-$$q^2$$ q 2 bin, the sensitivity to $$\lambda _B$$ λ B is almost comparable to $$B^- \rightarrow \mathrm {\ell }^- \bar{\nu }_{\mathrm {\ell }}\gamma $$ B - → ℓ - ν ¯ ℓ γ when $$\lambda _B$$ λ B is small, but with an added uncertainty from the light-meson intermediate resonance contribution. The sensitivity degrades with larger $$q^2$$ q 2 .


2021 ◽  
Vol 2 ◽  
Author(s):  
Arthur Jakobs ◽  
Simon Schulte ◽  
Stefan Pauliuk

Hybrid Life Cycle Assessment (HLCA) methods attempt to address the limitations regarding process coverage and resolution of the more traditional Process- and Input-Output Life Cycle Assessments (PLCA, IOLCA). Due to the use of different units, HLCA methods rely on commodity price information to convert the physical units used in process inventories to the monetary units commonly used in Input-Output models. However, prices for the same commodity can vary significantly between different supply chains, or even between various levels in the same supply chain. The resulting commodity price variance in turn leads to added uncertainty in the hybrid environmental footprint. In this paper we take international trading statistics from BACI/UN-COMTRADE to estimate the variance of commodity prices, and use these in an integrated HLCA model of the process database ecoinvent with the EE-MRIO database EXIOBASE. We show that geographical aggregation of PLCA processes is a significant driver in the price variance of their reference products. We analyse the effect of price variance on process carbon footprint intensities (CFIs) and find that the CFIs of hybridised processes show a median increase of 6–17% due to hybridisation, for two different double counting scenarios, and a median uncertainty of −2 to +4% due to price variance. Furthermore, we illustrate the effect of price variance on the carbon footprint uncertainty in a HLCA study of Swiss household consumption. Although the relative footprint increase due to hybridisation is small to moderate with 8–14% for two different double counting correction strategies, the uncertainty due to price variability of this contribution to the footprint is very high, with 95% confidence intervals of (−28, +90%) and (−23, +68%) relative to the median. The magnitude and high positive skewness of the uncertainty highlights the importance of taking price variance into account when performing hybrid LCA.


2021 ◽  
Author(s):  
Frédéric Guattari ◽  
Pierrick Auregan ◽  
Elliot de Toldi ◽  
Theo Laudat ◽  
Laurent Mattio

<p><span><span>To install a seismometer with a properly defined orientation - inside a vault or into a borehole - as a single station including various instruments or as a part of an array - an ‘adequate’ tool and an ‘absolute’ reference are needed.</span></span></p><p><span><span>In the past, and sometimes it persists nowadays, magnetic North have been used as a reference for Z-orientation of seismic station. Several studies have extensively measured the orientation error that have been made with this method, using an optical gyrocompass providing True-North as a reference, and their work will be summarized here.</span></span></p><p><span><span>In these studies, optical Gyrocompass is said to be the good solution, even if it is too heavy, expensive, and difficult to export. This paper will explain how iXblue has overcome these limitations to design the new-born Seistans Optical Gyrocompass.</span></span></p><p><span><span>Moreover, to aim True-North with a reliable accuracy is not the only think you need to do on the field. The method to transfer the North-line from the gyrocompass to the instrument to aligned must not induce errors that ruined the accuracy obtained using state-of-the-art gyrocompass. So an exhaustive study of the different ways to transfer the orientation from the compass to the aligned sensor will be presented, and corresponding added uncertainty will be evaluated, which is a good way to promote good practice on the field.</span></span></p><p><span><span>Finally, some figures will be gathered and shared from literature to quantify the precision needed for the alignment of a seismic sensor. There are today so few papers about this important matter that it is worth to spread their information.</span></span></p>


2021 ◽  
Author(s):  
Scott P. Seymour ◽  
Matthew R. Johnson

Abstract. Field measurement of flare emissions in turbulent flare plumes is an important and complex challenge. The simplest approaches necessarily assume that combustion species are spatially and/or temporally correlated in the plume, such that simple species ratios can be used to close a carbon balance to calculate species emission rates (i.e. emission factors) and flare conversion efficiency. This study examines the veracity of this assumption and the associated implications for measurement uncertainty. A novel tunable diode laser absorption spectroscopy (TDLAS) system is used to measure the correlation between H2O and black carbon (BC) volume fractions in the plumes of a vertical, turbulent, non-premixed, buoyancy-driven lab-scale gas flare. Experiments reveal that instantaneous, path-averaged concentrations of BC and H2O can vary independently and are not necessarily well-correlated over short time intervals. The scatter in the BC / H2O ratio along a path through the plume was well beyond that which could be attributed to measurement uncertainty and was asymmetrically distributed about the mean. Consistent with previous field observations, this positive skewness toward higher BC / H2O ratios implies short, localized, and infrequent bursts of high BC production, that are not well-correlated with H2O. This demonstrates that the common assumption of fixed species ratios is not universally valid, and measurements based on limited samples, short sampling times, and/or limited spatial coverage of the plume could be subject to potentially large added uncertainty. For BC emission measurements, the positive skewness of the BC / H2O ratio also suggests that results from small numbers of samples are more likely to be biased low. However, a bootstrap analysis of the results shows how these issues should be easily avoidable with sufficient sample size and provides initial guidance for creating sampling protocols for future field measurements using analogous path-averaged techniques.


Author(s):  
Mohamed Dabees

Climate change and sea level rise (SLR) present a challenge and added uncertainty for managing coastal areas. Many coastal cities and developed coastal areas are assessing future vulnerabilities to SLR and developing adaptation plans for improved resiliency. Equilibrium conditions for beach planform can be critical to the long-term stability of beaches and dunes fronting coastal cities. In many cases, resiliency and adaptation programs for beachfront areas are based on assumptions of evaluating scenarios of higher water elevations and hydrodynamic forcing under present time topographic and bathymetric conditions. These evaluation parameters suggest that the coastline and existing morphological features are near equilibrium condition and are expected to remain near similar equilibrium over the SLR scenarios under consideration. Such assumptions may be limited to open coast conditions where the beach and the developed coastal planform follows theoretical open coast conditions or constant equilibrium planform. This paper discusses factors influencing beach planform along the Florida Atlantic and Gulf of Mexico coastlines and proposes conceptual methodologies in various applications.Recorded Presentation from the vICCE (YouTube Link): https://youtu.be/gWsbmi6VIo0


2020 ◽  
Vol 7 (1) ◽  
pp. e538
Author(s):  
Maria del Mar Amador ◽  
Marcela Gargiulo ◽  
Christilla Boucher ◽  
Ariane Herson ◽  
Stéphanie Staraci ◽  
...  

ObjectiveWe aimed to describe the population of subjects seeking presymptomatic counseling for amyotrophic lateral sclerosis and/or frontotemporal dementia (ALS/FTD) and compared them with those demanding the well-established presymptomatic test for Huntington disease (HD).MethodsWe retrospectively examined the requests of a cohort of individuals at risk of familial ALS/FTD and 1 at risk of HD over the same time frame of 11 years. The individuals were seen in the referral center of our neurogenetics unit.ResultsOf the 106 presymptomatic testing (PT) requests from subjects at risk of ALS/FTD, 65% were seen in the last 3 years. Over two-thirds of the subjects were at risk of carrying mutations responsible for ALS, FTD, or both. Sixty-two percent of the subjects came from families with a known hexanucleotide repeat expansion in C9ORF72. During the same period, we counseled 840 subjects at risk of HD. Subjects at risk of ALS/FTD had the presymptomatic test significantly sooner after being aware of their risk, but were older than those at risk of HD. The youngest subjects requesting the test had the highest disease load in the family (p < 0.05).ConclusionsDemands for PT for ALS/FTD have been increasingly growing, particularly since the discovery of the C9ORF72 gene. The major specificity of the genetic counseling for these diseases is the unpredictability of the clinical phenotype for most of the genes involved. Awareness of this added uncertainty does not prevent individuals from taking the test, as the dropout rate is not higher than that for HD.


2019 ◽  
Vol 249 ◽  
pp. F3-F3

Recent trends in global industrial production and trade show activity stalling since late last year. The pace of service sector activity has remained steadier.Tariff increases and trade disputes have contributed to the weakness in production and trade and have added uncertainty to the global economic outlook.In response to weaker production activity and continued low inflation, central banks in many economies have either loosened monetary policy or positioned themselves to do so, which has been reflected in financial markets.Taking these forces into account, we have reduced our forecast for global GDP growth this year slightly to 3¼ per cent. This is likely to be, by a small margin, the slowest annual growth for a decade. We expect output growth to show a slight pick-up in 2020 to 3½ per cent.


2019 ◽  
Vol 15 (S352) ◽  
pp. 114-114
Author(s):  
Emma Curtis-Lake

AbstractThe mass-SFR relation of galaxies encodes information of present and historical star formation in the galaxy population. We expect the intrinsic scatter in the relation to increase to low mass where SFR becomes more stochastic. Measurements at z ‰ 4 from the Hubble Frontier fields have hinted at this (Santini et al., 2017), however, with the added uncertainty of lensing magnification we await JWST to provide robust measurements. Even with data-sets provided by JWST, uncertainties on mass and SFR estimates are often large, potentially covariant and dependent on assumptions used. I will present our method of Bayesian hierarchical modelling of the mass-SFR relation that self-consistently propagates uncertainties on mass and SFR estimates to uncertainties on the mass-SFR relation parameters. I will expose the biases imposed by standard SED-modelling practices, and address to what significance we can measure an increase in intrinsic scatter to low masses with JWST.


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