dataesr/scientific-paragraphs-categorization huggingface dataset:
Despite expectations of substantial growth in Unmanned Aircraft Systems (UAS, also called drones) there is currently no large-scale system in place to manage UAS operating in shared airspace. Many countries are developing UAS Traffic Management (UTM) concepts which, unlike conventional air traffic management (ATM), seek to foster a competitive market involving many private actors and service providers and which rely on the cooperative and distributed management of UAS. This paper focusses on the economic policy dimensions of UTM. It describes the main participants, activities and commercial interactions of the emerging UTM concepts in the European Union and the United States. Building on these descriptions, we then consider some of the fundamental choices and trade-offs confronting policymakers when developing an economic policy framework for UTM such as: which activities should be competitive; how can access to scarce airspace be allocated in a safe, fair and efficient way; on what commercial terms will data be shared among participants; what infrastructure can cater for large scale UAS operations; and to what extent should the economic regulatory frameworks for UTM and ATM be aligned.
As shown in Fig. 1 , a notable feature of most UTM concepts is that there is no direct communication channel between an ATM Service Provider and a UAS Operator. Rather all of the information about ATM system operations is provided to a Common Information Services Provider or a UTMSP in the first instance, who then determines the constraints in which a UAS operator can safely operate. In addition, while in Fig. 1  a UAS Operator and UTM service provider are shown as distinct entities, in practice these activities could be integrated such that a single entity is both a UAS operator and a UTM Service Provider (e. g. : large logistics or package delivery UAS Operators may choose to act as their own UTM Service Provider). Fig. 1  also highlights the fact that many UTM concepts envisage the development of a local UTM network where UTM Service Providers (UTMSPs) operating in the same airspace will cooperate to negotiate flight plans and maintain direct connections to one another to share data in real-time.
UAS Operators have the option to selfsupply all of these services or can choose to use a third party UTM service provider (i. e. , a UAS Service Supplier (USS)) to support their operations. In the FAA's UTM Concept, a UAS Operator is the person or entity responsible for the overall management of their operation. 8 This includes meeting regulatory responsibilities; planning flight/operations; sharing operation intent information; and safely conducting operations using all available information. USS are entities which assist UAS Operators with meeting UTM operational requirements, and ensure information sharing across the UTM community. Among the functions of a USS are: to act as a communications bridge between federated UTM actors; to provide the Operator with information about planned operations in and around a volume of airspace; to archive operations data in historical databases for analytics, regulatory, and Operator accountability purposes.
Common Information Services in the FAA's UTM concept is provided through a Flight Information Management System (FIMS), which will support information exchanges and protocols between UTM participants and FAA systems, and other stakeholders (government agencies etc). Although the FAA will develop and manage the FIMS, it does not envisage itself as having an active operational role in UTM. Rather it sees it primary operational role as being to provide FAA-originated airspace constraint data through FIMS to airspace users (e. g. , airspace restrictions, facility maps, active Special Activity Airspace). As such, the FAA does not foresee using FIMS to receive dataintent data or otherwisefrom the USSs during nominal operations. During off-nominal situations, the USS notifies the FAA of an event via FIMS only if the situation meets the criteria for FAA/ATC attention.
Centralised UTM concepts rely on a single entity (e. g. : Common Information Service Provider) receiving and supplying relevant common data and information to all UTM participants in a particular region. In contrast, in a distributed UTM concept, interoperability is achieved through individual entities exchanging data and information using common standards and protocols at different stages of a mission (pre-flight, during mission, post-flight), with no centralised entity responsible for collecting and disseminating information. The feasibility of a distributed approach therefore depends on the universal adoption of common standards and protocols and on the development of policies relating to remote or network identification. While a distributed approach can achieve high levels of interoperability if standards and protocols are well designed and adopted by all participants, it may be necessary to establish a body to consider and assess changes to protocols or standards to deal with new volumes or forms of traffic.
2011 , commonly also known as pulse-phase jitter). Some basic properties for these three pulsars are given in Table  1. The observatory-specific details of the observations used are given in Table  2 , and the number and date ranges of the observations are given in Table  3. In addition to the telescope-specific radio-frequency interference (RFI) mitigation strategies described below, all data were visually inspected through the software suite psrchive  (Hotan et al. 2004; van Straten et al. 2012 ) before TOAs were derived as described in Sect. 3. Specifically, because the data near the edge of each sub-band are often corrupted by aliasing and spectral leakage problems, these channels were excised with the paz program.
Effelsberg radio telescope The EFF is a homological Gregorian design with a 100 m paraboloidal primary reflector and a 6. 5 m ellipsoidal secondary reflector. This makes EFF the world's second-largest fully mov- able telescope. It operates at wavelengths from about 90 cm to 3. 5 mm (i. e. observing frequencies from 300 MHz to 90 GHz). The data from the EFF presented in this research were acquired with a typical cadence of 3-4 weeks between 2011 and 2019 with an integration time per source of about 30 min per observation. The data recorder (henceforth referred to as backend) used was the PSRIX pulsar-timing system  (Lazarus et al. 2016) , which is based on the reconfigurable open architecture computing hardware (ROACH) boards and carries out coherent dedispersion on central processing units (CPUs) using the dspsr (van Straten & Bailes 2011) package.
The observations were taken with the P-217 and P-200 receivers, centred at 1. 3475 GHz in a frequency-multiplexing mode where eight 25 MHz wide sub-bands are independently dedispersed and written to disk. This results in observations with a total of 200 MHz of bandwidth, 128 frequency channels, 1024 phase bins, 10-s integrations, and full polarisation information. These data were combined in time and frequency with the psradd command of the psrchive package  (Hotan et al. 2004; van Straten et al. 2012). Subsequently, RFI was removed automatically with clean. py, the RFI excision script of the coastguard package  (Lazarus et al. 2016 ), using the "surgical" algorithm.
Lovell radio telescope At Jodrell Bank Observatory, the 76-m Lovell telescope is used in a regular pulsar-monitoring programme. The observations used in this work were taken from that programme, have a A181, page 3 of 11 A&A 658, A181 (2022) centre frequency of 1. 532 GHz, a time span of ∼7. 5 years, a typical cadence of three weeks, and a typical integration time of 15 min. For PSR J1713+0747, the cadence was closer to one week. The backend used for these observations was a ROACHbased backend very similar to the one used at the EFF and described by  Lazarus et al. (2016) , and using the dspsr package (van Straten & Bailes 2011) for real-time coherent dedispersion. The JBO observations have a bandwidth of 400 MHz split over 25 16 MHz wide sub-bands, each channeled into 1 or 0. 25 MHz wide frequency channels.
Data processing techniques In this section we describe the different algorithms and methods we used and compared. Specifically, the template creation methods are described in Sect. 3. 1, the template-matching methods are outlined in Sect. 3. 2, and the analysis in which we determined the most useful TOA bandwidth is described in Sect. 3. 3. All of these algorithms and methods make use of the psrchive and tempo2  (Hobbs et al. 2006 ) software packages.
TOA determination methods After creating a template profile, the TOA of a given observation can be determined by matching the observation to this template. Specifically, the observation O can be related to the template T as  (Taylor 1992 ) O(φ) = a + bT (φ + τ) + n(φ), where φ is the rotational phase, a is an arbitrary offset, b is a scale factor, τ is the phase offset between observation and template, and n(φ) is a noise term. In order to solve for τ, a variety of possible approaches have been proposed. We compare three of the more commonly used methods, which are briefly described below. Fourier phase gradient (PGS). The most common templatematching method used to date (and the default method used in the psrchive software package) is the so-called PGS method, described in detail by  Taylor (1992).
Consequently, there must be a most useful TOA bandwidth that maximises the TOA precision by limiting the deleterious effects of low S/N in fine frequency channels and those due to scintillation and profile evolution in frequency-averaged TOAs. Here we have investigated such a most useful TOA bandwidth for a set of pulsar and backend combinations by quantifying the achievable timing precision as a function of the TOA bandwidth. To do this, we combined the best template-matching method with a frequency-resolved version of the optimal template profile and then carried out the timing of each pulsar and backend combination of our test dataset for a range of possible TOA bandwidths. This allowed us to investigate the improvement in the goodness of fit (of the timing model to the TOAs) via the reduced chi-squared of the linearised least-squares fit and the rms of the timing residuals, as well as the number of TOAs that remain after removing TOAs corresponding to total intensity profiles with S/N lower than 8, following  Arzoumanian et al.
Simulations Because the analysis of real data is complex and multi-faceted, we first carried out some relatively straightforward simulations to gain information about a few key points of the subsequent analysis. Specifically, we used simulations to study how the TOA uncertainties from the various TOA determination methods scale with pulse S/N and to determine to which degree these results depend on the pulse shape. Furthermore, because these tests depend on the S/N that is used to place a cut-off to remove unreliable TOAs (in accordance with the advice of  Arzoumanian et al. 2015) , TOA bandwidth [MHz] Mean Scint. BW 1/ TB Theoretical fit Weighted RMS res [ s] Fig. 2. A sketch of the dependence of σ res on TOA bandwidth, for an idealised dataset. The black dots represent rms values, the blue dashed line indicates the median scintillation bandwidth and the red line is a fit of Eq.
(  2 ). The black line is for the case of pure radiometer noise, i. e. with no jitter or other corrupting noise sources (σ NF = 0) and for standard scaling following the radiometer equation (α = -1). we also evaluated how well the standard S/N algorithm of the psrchive package can reproduce the simulated S/N. These simulations were written in python using the numpy package and psrchive through its python interface. Specifically, noise-free templates were constructed with the paas routine of psrchive, after which white noise with varying intensity was added to these profiles. Here we tested five profile shapes as shown in the inset plots of Fig. 3 : a simple Gaussian profile, a Gaussian profile with a sharp notch on its trailing edge, and finally, the analytic profiles derived for each of our three test pulsars, based on the NRT data described earlier.
TOA bandwidth For each pulsar, the timing performance as a function of the TOA bandwidth was assessed using TOAs created with the 'added' template with the FDM CCA by splitting the archives into multiple channels. (In doing so, the template was split into the  A&A 658, A181 (2022)  same number of channels, implying that each channel was timed against a template at its own frequency). The exact choice of the number of channels is specific to the telescope to accommodate the different bandwidths. At the EFF, the NRT, and the WSRT, the fully frequency-resolved archives were first averaged down to 32 channels and subsequently averaged down by factors of two. Because the native resolution at Jodrell Bank is different, the JBO data were first averaged down to 40 channels (or fewer) and were subsequently averaged down by factors of either 2.
Acknowledgements. The EPTA is a multinational European collaboration, which consists ASTRON (NL),  INAF/Osservatorio Astronomico di Cagliari (IT), Max-Planck-Institut für Radioastronomie (GER) ,  Observatoire de Paris/Nançay(FRA) , the  University of Manchester (UK) , the  University of Birmingham (UK) , the  University of Cambridge (UK)  and the  University of Bielefeld (GER). J. W. acknowledges support from the  China scholarship council. J. P. W. V. acknowledges support by the  Deutsche Forschungsgemeinschaft (DFG)  through the  Heisenberg programme  (Project No. 433075039 ). Part of this work is based on observations obtained the 100-m telescope of the  MPIfR (Max-Planck-Institut für Radioastronomie) at Effelsberg. Pulsar research at the Jodrell Bank Centre for Astrophysics  and the observations using the Lovell Telescope is supported by a consolidated grant from the  STFC  in the UK.
The Nançay Radio Observatory is operated by the  Paris Observatory , associated with the  French Centre National de la Recherche Scientifique (CNRS). We acknowledge financial support from the  Action Fédératrice PhyFOG  funded by  Paris Observatory  and from the  "Programme National Gravitation, Références, Astronomie, Métrologie" (PNGRAM ) funded by  CNRS/INSU  and  CNES, France. The Westerbork Synthesis Radio Telescope is operated by the  Netherlands Institute for Radio Astronomy (ASTRON)  with support from The  Netherlands Foundation for Scientific Research NWO.
Reagents and Apparatus The crystal structure of La(OH) 3 @MWCNT nanocomposite was examined using powder X-ray diffraction (XRD) data collected using a high-resolution SmartLab ® X-ray diffractometer (Rigaku, Japan) with a Cu Kα radiation source. The operating current and voltage were 30 mA and 40 kV, respectively. For the experiments, the dried powders were flattened with a zero-background silicon plate. Diffraction data were collected in the range of 10-60 • 2θ with a step of 0. 03 • and recording speed of 2 • /min. The average crystallite size was estimated by applying Scherrer's equation on the most intensive diffraction peaks (Ls = κλ/βscos(θB. The morphology and surface properties of nanocomposite used for electrode modification were investigated using a field emission-scanning electron microscope FE-SEM MIRA3 (Tescan, Czech Republic) operating at 20 keV.
The CV signals of UA using these modified electrodes were similar, so for the selection of the optimal electrode for further experiments, we used the data obtained from the electrochemical characterization of all electrodes, as previously described. The La(OH) 3 /CP electrode had the poorest CV response based on these measurements, most likely due to a decrease in electrode active surface area. MWCNTs promoted electron transfer and decreased the interfacial resistance, and better CV response was achieved when MWCNTs/CP were used. The La(OH) 3 likely makes the entire complex of MWCNTs and La(OH) 3 more porous, which can help improve the response of the modified electrode. All of this led to the conclusion that the synergistic effect of MWCNTs and La(OH) 3 improved the modified electrode's electrochemical properties, which will contribute to the sensor's analytical performance for uric acid detection.
Environmental Impact of the Analysis While developing an analytical procedure, attention is being shifted more and more to its ecological acceptability. Several methods can assess the green aspects of an analytical procedure in which the green analytical procedure index (GAPI) (Scheme 3A) and Analytical GREEnness metric approach and software (AGREE) (Scheme 3B) are used. While GPAI is the most comprehensive and has the advantages of graphically describing all relevant factors-quantification; sample collection, preservation, transport and storage; sample preparation; reagents and compounds used and instrumentation, AGREE enables straightforward interpretation, since the level of greenness is expressed numerically on a scale from 0 to 1, with 1 being the greenest. Furthermore, AGREE contains all the relevant data about the analytical procedure and is easy to generate thanks to a free software downloadable from https://mostwiedzy.
Funding: This work was supported by  Ministry of Education, Science and Technological Development of Republic of Serbia  Contract number:  451-03-68/2022-14/200168 , and the research was funded by  Ministry of Science and Higher Education of the Russian Federation  (agreement No. 075-15-2022-1135 ) and  South Ural State University. Institutional Review Board Statement: Not applicable. Informed Consent Statement: Not applicable.
Other relevant research Shirazi and his coworkers have conducted several experimental and analytical projects related to sand transport, erosion, and monitoring in the Tulsa University Sand Management Projects. Of particular interest is the evaluation of how characteristics of the carrier fluid affects erosion rates, exemplified by  Okita et al. (2012). They found that viscosity of the carrier fluid significantly reduces the erosion rate of small and medium-sized particles. Since the experimental setup utilized by Okita does not completely apply to MPP conditions, the results should not be applied to the MPP erosion model without further validation. Morrison et al. (2015 Morrison et al. ( , 2017) )  conducted a sand test to obtain experimental data on wear in electric submersible pumps (ESPs).
Measured sand data Every day, a sample of the process fluid was taken from the inlet of the topside separator. The sand concentration was established from a lab analysis performed on the sample. The sand concentration is assumed to be constant for 24 h. It is further assumed that the concentration of sand in the pump and the pump station recirculation line is equal to the sand concentration measured topside. Following the sand screen failure in August 2017, the MPP was subject to more than 250 metric tons of sand. The high concentration measured on January 18 (16,500 mg/L) and February 10 (22,600 mg/L) 2018 have made a significant contribution to the overall sand production. It is uncertain whether this high concentration has lasted for as long as 24 h. At the same time, short periods of extremely high concentration may have occurred on other days without being captured in the daily sample.
Modeled wear Known pump operating conditions, process parameters, and sand data in combination with measured impeller wear is a unique set of information. Retrospective operational data from Moho were applied in the MPP wear model. Comparing the modeled wear to measured wear could allow for valuable field validation of the wear model. Daily average values of the following parameters were supplied by the operator as retrospective model input  Figure  11. Impeller wear areas. • Sand production, mg/L Sand data used in the model were based on the samples described in the previous section. • Average sand grain size =158 μm • Sand hardness factor =1 (equivalent to quartz) • Sand form factor =1 (sharp) The wear model applies the wear properties of tungsten carbide coating until the coating is punctured and duplex properties for the further wear.
Today, digital twins, i. e. the virtual representations of the physical infrastructure, in conjunction with AI, enable dynamic and adaptive modelling of hazard impacts on infrastructure, as well as automated and intelligent identification of deterioration and damage  (Sacks et al. , 2020). A recent example of the extensive use of digital technologies in rapid decision-making is the assessment of the landmark Polyfytos bridge crossing the homonymous lake 1. The resilience of the bridge and impact on the road network were evaluated based on visual inspections and collection of digital data by (a) high-definition photography with a camera mounted on a UAV processed with photogrammetry methods, validated by surveying measurements of the structure using a monitoring-grade total station and highprecision multi-hour static global navigation satellite system (GNSS) measurements of its stationary points.
Fouling of heat exchanger surfaces is a major concern in the industry, resulting in performance losses through a decrease in the overall heat exchange coefficient. Control methods exist but are costly and have a strong environmental impact. Thus, the use of physical treatments is very promising, because the action is done on the clogged surface, in the bulk or in the solution. The present study shows the influence of ultrasonic guide waves on the crystallization of calcium carbonate inside a plate heat exchanger from scaled water. An experimental pilot was set up to study the scaling phenomenon. Several operating parameters such as flow rate, duration, and temperature were experimentally varied in order to identify their influence on the scale deposition in the heat exchanger. Subsequently, a thermodynamic prediction was performed by geochemical modeling using the Phreeqc software in order to get an idea of the nature of the deposit formed after the heating of scaled water.
Geochemical modeling Monitoring the formation of scale inside the exchanger requires the ability to predict the nature of the scale formed and also to determine which mineral phase is likely to precipitate through geochemical modeling. A prediction was made using the Phreeqc interactive 3. 4. 0 USGS software (pH-Redox-Equilibrium-Calculations). This computer program based on a C programming language  [25]. Version 1 Phreeqc, is capable of simulating a variety of geochemical reactions for a system including: -mixing of waters; -the addition of net irreversible reactions to the solution; -the dissolution and precipitation phases to reach equilibrium with the aqueous phase; -the effects of temperature changes. Phreeqc interactive can calculate elemental concentrations, molarities and activities of aqueous species, pH, PE, saturation index, speciation, batch reaction, and one-dimensional (1D) transport calculations involving reversible reactions, solid solution, surface complexation, and ion exchange equilibria, irreversible reactions, kinetically controlled reactions, solution mixing, temperature changes and inverse modeling  [26].
In this geochemical modeling, the system is considered to be in thermodynamic equilibrium and not all kinetic considerations are taken into account. Geochemical modeling requires initial input constraints (Table  2 ). This programming language in this case consists of water chemistry analyses such as Ca 2+ , Mg 2+ and carbonate concentration, units of measure, temperature, dissolved gas content, pH, and redox potential  [27]. The ionic strength I of the reaction medium is calculated according to the following relationship: I = 1/2 ∑ NC i=1 C i z 2 i (2) With, C i the molar concentration of species i (mol. L -1 ); zi: the ionic charge. Since this study focuses on experimental tests conducted on natural waters, the ionic strength of the media does not exceed 7. 9 × 10 -3 mol/ Kgw. Thus, a thermodynamic database such as Thermodemm (BRGM 2017) is suitable for simulating the different equilibria establishing on the cold side, at a given temperature  [28].