bluuebunny/crossref_metadata_2025 huggingface dataset:
Perspetivas de Gestão Pós-Fogo: Revisão da Literatura e Análise dos Discursos dos Agentes em Portugal
Authors: Ribeiro Cristina , Valente Sandra , Fleskens Luuk , Keizer Jan Jacob , Coelho Celeste
Published: January 2021

O aumento da frequência, intensidade e recorrência dos fogos rurais nos países do Sul da Europa, e em particular em Portugal, tem evidenciado a necessidade de definir uma estrutura de gestão florestal pós-fogo, que atue no risco de degradação dos ecossistemas a nível local, na prevenção de potenciais danos nos valores em risco a jusante, na promoção da regeneração florestal e na diminuição da frequência e severidade de incêndios futuros. Este artigo pretende discutir a(s) abordagen(s) à gestão florestal pós-fogo, através de uma revisão da literatura científica usando como termos de pesquisa ‘post-fire management’ e ‘forest’, e da análise dos discursos de agentes responsáveis pela operacionalização de projetos de gestão pós-fogo, financiados no âmbito do Programa de Desenvolvimento Rural em Portugal. Os resultados revelaram que a gestão florestal pós-fogo é um tema recente, de natureza complexa e dinâmica, que tem estado mais focado na componente ecológica. No entanto, existe um reconhecimento progressivo da importância de integrar novos aspetos, tais como a análise de custo-benefício e o envolvimento dos agentes.
Stärkt die Tiergestützte Therapie die sozialen Kompetenzen bei der ADHS?
Authors: Mayer Julia Doreen
Published: January 2021

Die Tiergestützte Therapie kommt in der Psychiatrie häufig zum Einsatz – und das nicht ohne Grund: Es ist bekannt, dass Tiere einen positiven Einfluss auf Menschen haben. Ob der Kontakt zu Tieren sich auch effektiv auf den Verlauf der Aufmerksamkeitsdefizit-/Hyperaktivitätsstörung auswirkt, erörtert unsere Autorin.
Das Münchhausen-Stellvertreter-Syndrom
Authors: Dißmann Steffen
Published: January 2021

Wenn Eltern ihre Kinder absichtlich verletzen, krank machen oder zu Tode quälen, ist das grausam. Denn die Opfer leider nicht nur unter den Schmerzen, sondern ihnen wird häufig auch nicht geglaubt, sodass sie schutz- und hilflos den Misshandlungen der Eltern ausgesetzt sind. Welche Motive und Merkmale auf das Münchhausen-Stellvertreter-Syndrom hindeuten und wie sich Auffälligkeiten frühzeitig erkennen lassen, schildert unser Autor.
Potenziale und Herausforderungen von E-Mental-Health-Interventionen in der Versorgung psychischer Störungen
Authors: Köhnen Moritz , Dirmaier Jörg , Härter Martin
Published: January 2021

E-Mental-Health-Interventionen bieten bei der Versorgung von Menschen mit psychischen Störungen viele Potenziale: Sie sind zeit- und ortsunabhängig, bauen Zugangsbarrieren ab und können Versorgungslücken schließen. Welche Chancen und Herausforderungen die digitalen Technologien eröffnen, erläutern unsere Autoren.
Antipsychotische Polypharmazie in der Behandlung von Patientinnen und Patienten mit Schizophrenie am Beispiel von neun psychiatrischen Fachkliniken des Landschaftsverbandes Rheinland
Authors: Schmidt-Kraepelin Christian , Meisenzahl-Lechner Eva , Kujovic Milenko , Cordes Joachim , Engelke Christina , Riesbeck Mathias , Zielasek Jürgen , Engemann Sandra , Vrinssen Jürgen , Lehmann Isabell , Tönnesen-Schlack Anita , Banger Markus , Grümmer Martine , Scherbaum Norbert , Muysers Jutta , Rinckens Stephan , Marggraf Ralph , Gouzoulis-Mayfrank Euphrosyne
Published: January 2021

Hintergrund Für die Behandlung von Menschen mit Schizophrenien wird vorrangig antipsychotische Monotherapie empfohlen. Antipsychotische Polypharmazie (APP) wird dennoch oft eingesetzt und dient als Qualitätsindikator.

Ziel der Arbeit Das Auftreten von APP an 9 psychiatrischen Kliniken des LVR zu untersuchen und die Nutzbarkeit als Qualitätsindikator zu diskutieren.

Material und Methoden Es wurden Behandlungsdaten von stationären und teilstationären Fällen mit der Hauptdiagnose ICD-10 F20.x im Zeitraum 6/2016 bis 6/2017 hinsichtlich der APP-Rate analysiert.

Ergebnisse Bei 6788 Behandlungsfällen wurde eine APP-Rate von 55,5 % ermittelt. Männliches Geschlecht, längere Verweildauer, keine Zwangsunterbringung und der Standort der Klinik waren mit APP assoziiert.

Diskussion Die APP-Rate ist im Vergleich bisherigen Ergebnissen hoch und weist erhebliche Unterschiede zwischen den Kliniken auf. Die Verwendung des Qualitätsindikators APP wird diskutiert.
Gestational Risk as a Determining Factor for Cesarean Section according to the Robson Classification Groups
Authors: Soares Karina Biaggio , Klein Vanessa Cristina Grolli , Lima José Antônio Reis Ferreira de , Gadenz Lucas , Paulo Larissa Emile , Konopka Cristine Kolling
Published: January 2021

Objective To analyze and compare the frequency of cesarean sections and vaginal deliveries through the Robson Classification in pregnant women attended at a tertiary hospital in two different periods.

Methods Cross-sectional, retrospective study of birth records, comprising 4,010 women, conducted from January 2014 to December 2015 in the only public regional referral hospital for the care of high- risk pregnancies, located in Southern Brazil.

Results The overall cesarean section rate reached 57.5% and the main indication was the existence of a previous uterine cesarean scar. Based on the Robson Classification, groups 5 (26.3%) and 10 (17.4%) were the most frequent ones. In 2015, there was a significant increase in the frequency of groups 1 and 3 (p < 0.001), when compared with the previous year, resulting in an increase in the number of vaginal deliveries (p < 0.0001) and a reduction in cesarean section rates.

Conclusion The Robson Classification proved to be a useful tool to identify the profile of parturients and the groups with the highest risk of cesarean sections in different periods in the same service. Thus, it allows monitoring in a dynamic way the indications and delivery routes and developing actions to reduce cesarean rates according to the characteristics of the pregnant women attended.
Effect of Preoperative Urodynamic Study on Urinary Outcomes after Transobturator Sling
Authors: da Cruz Pedro Rincon Cintra , Dias Filho Aderivaldo Cabral , Furtado Gabriel Nardi , Ferreira Rhaniellen Silva , Resende Ceres Nunes
Published: January 2021

Objective To evaluate whether performing preoperative urodynamic study influences postoperative urinary symptoms of women with stress urinary incontinence that underwent transobturator sling.

Methods Retrospective analysis of patients treated for stress urinary incontinence by transobturator sling from August 2011 to October 2018. Predictor variables included preoperative urodynamic study, age, incontinence severity, body mass index, preoperative storage symptoms and previous anti-urinary incontinence procedure. Outcome variables were postoperative subjective continence status, storage symptoms and complications. Logistic regression after propensity score was employed to compare outcomes between patients who underwent or not pre-operative urodynamic study.

Results The present study included 88 patients with an average follow-up of 269 days. Most patients (n = 52; 59.1%) described storage symptoms other than stress urinary incontinence, and 38 patients (43.2%) underwent preoperative urodynamic studies. Logistic regression after propensity score did not reveal an association between urinary continence outcomes and performance of preoperative urodynamic study (odds ratio 0.57; confidence interval [CI]: 0.11–2.49). Among women that did not undergo urodynamic study, there was a subjective improvement in urinary incontinence in 92% of the cases versus 87% in those that underwent urodynamic study (p = 0.461). Furthermore, postoperative storage symptoms were similar between women who did not undergo urodynamic study and those who underwent urodynamic study, 13.2% versus 18.4%, respectively (p = 0.753).

Conclusion Preoperative urodynamic study had no impact on urinary incontinence cure outcomes as well as on urinary storage symptoms after the transobturator sling in women with stress urinary incontinence.
Pediatric Epilepsy Surgery in Focal and Generalized Epilepsy: Current Trends and Recent Advancements
Authors: Harris William B. , Phillips H. Westley , Fallah Aria , Mathern Gary W.
Published: January 2021

For a subset of children with medically intractable epilepsy, surgery may provide the best chances of seizure freedom. Whereas the indications for epilepsy surgery are commonly thought to be limited to patients with focal epileptogenic foci, modern imaging and surgical interventions frequently permit successful surgical treatment of generalized epilepsy. Resection continues to be the only potentially curative intervention; however, the advent of various neuromodulation interventions provides an effective palliative strategy for generalized or persistent seizures. Although the risks and benefits vary greatly by type and extent of intervention, the seizure outcomes appear to be uniformly favorable. Advances in both resective and nonresective surgical interventions provide promise for improved seizure freedom, function, and quality of life. This review summarizes the current trends and recent advancements in pediatric epilepsy surgery from diagnostic workup and indications through surgical interventions and postoperative outcomes.
Significance and Impact of the Intersphincteric Plane Sepsis in the Management of the Perianal Sepsis: Ultrasound Study
Authors: Youssef Ashraf Talaat
Published: January 2021

Background The intersphincteric plane (ISP) is a potential space between the external and the internal anal sphincters. About 90% of the perianal sepsis is caused by an obstruction of the ducts of anal glands with subsequent secondary bacterial infection. The imaging modalities used to diagnose perianal sepsis are the ultrasound via endoanal and transperineal routes and magnetic resonance imaging.

Objective  The study aimed to identify the various patterns of the ISP sepsis and their incidence among our study group and to clarify the significance of ISP in the pathogenesis of anorectal abscesses and various types of perianal fistula tracts, to optimize the surgical management.

Methods Retrospective descriptive study in which 57 patients with an ISP sepsis were evaluated with full medical history, clinical exam, and ultrasound; the final diagnosis was based on combining the results of ultrasound, digital rectal examination under anesthesia, and the operative results.

Results The current study showed many patterns of the ISP sepsis and estimated the incidence of each pattern among our study group; such patterns could be fistula tracts, sinus tracts, abscesses, intersphincteric abscess with supralevator extension, sinus with abscess formation, fistula with abscess formation, distension of the ISP with free pus, and other complex patterns like horse abscess, abscess with transsphincteric sinus, and ISP fistula/sinus with transsphincteric branches.

Conclusion Understanding the role of the ISP in the pathogenesis of anorectal abscesses and perianal fistula tracts can help in reaching the optimum way of management.
Strained agricultural farming under the stress of youths’ career selection tendencies: a case study from Hokkaido (Japan)
Authors: Usman Muhammad , Sawaya Akinori , Igarashi Mari , Gayman Jeffry Joseph , Dixit Rakesh
Published: January 2021

Although job availability in Japan is at its highest in 24 years, the unemployment rate has remained unchanged. On one hand, certain fields are saturated with employees while on the other hand, the rural areas of Hokkaido are in desperate need of agricultural workers. At the same time, the aging population in Japan is an emerging challenge. The flat unemployment rate in conjunction with the rapidly aging farmers’ population can possibly reduce the food self-sufficiency rate, raise Japan’s dependency for international food products and increase import expenses. Thus, these factors can tip the socio-economic balance of the struggling economy. For the present research, different surveys were conducted not only in various farming corporations of Hokkaido but also 20 farmers were directly contacted and interviewed. In addition, adolescents’ (aged 16–18 years) career choices were studied through questionnaires administered to 157 students at Hokkaido’s Sapporo Kaisei Secondary School. It was found that, in rural areas of Hokkaido, relocation of youth to the cities is probably the main cause of the shortage of workers. In Sapporo city, among adolescents who had already chosen a career path, around 76% wanted to enter the science and technology field. This trend can result in intense competition and “saturation” in science and technology fields and many vacant slots in the others related to agricultural farming. This behavior is probably maintaining the unemployment rate, regardless of the number of job vacancies. In addition, according to our survey, considering career paths, parents and teachers provide general guidance that has very little influence on adolescents’ career decisions. So, a more detailed career counseling is suggested.
Way of the Weedy Seadragon
Authors: Morgan Anne , Bury Lois
Published: January 2021

Can you imagine a strange and colourful fish that looks like a dragon? It can’t fly or breathe fire, but it is an excellent dancer!
The weedy seadragon is an amazing fish with a talent for camouflage, weird eating habits and a unique courtship dance. But its habitat and future are threatened. This enchanting story takes you under the sea to meet this mysterious sea creature, and reveals its weird and wonderful ways.
Do you believe in dragons?
Written by Anne Morgan, and beautifully illustrated by Lois Bury, The Way of the Weedy Seadragon invites you to dive into the astonishing lives of one of the world’s most curious sea creatures.
The use of le 了 in Mandarin Chinese oral discourse
Authors: Li Xiaoshi , Li Wenjing , Cui Yaqiong
Published: January 2021

leis the mostly widely studied aspect marker in Chinese. In addition to perfective aspect marker to indicate action completion,lecan also serve as a sentence-final particle to indicate a currently relevant state. This study investigates how Chinese native speakers uselein oral discourse and the factors that influence their use. The data were collected from three discourses including informal conversations, elicited narratives, and teacher classroom speech. Multivariate analysis of 2,359 tokens revealed that verb complement type and verb type have the strongest effects, followed byleposition, serial verb relationship, sentence type, discourse context, and time word presence/absence.
Research on the formation process of selective laser melting Mg–Y–Sm–Zn–Zr alloy
Authors: Wang Wenli , He Lun , Yang Xin , Wang Dan
Published: January 2021

Selective laser melting technology was proposed to form the multi-element mixed rare earth magnesium alloys of Mg–3.4Y–3.6Sm–2.6Zn–0.8Zr (wt-%). The formation process, relative density, evaporation, microstructure and microhardness of the deposited samples at different laser power and scanning speed were characterised. Under the experimental conditions with a laser power of 40 W and a scanning speed of 300 mm s−1, the maximum relative density of the sample is 98.6%. The evaporation of elements exists but is not serious under all process parameters. Compared with the as-cast process, the microstructure of the samples prepared by SLM is mainly composed of α-Mg matrix and (Mg, Zn)3(Y, Sm) eutectic phase, Mg12(Y, Sm)Zn eutectic phase and LPSO structure are not found.
Multipole polarizabilities and critical phenomena of hydrogen-like atoms in dense quantum plasmas
Authors: Jiao Li Guang , He Yu Ying , Zhang Yong Zhi , Ho Yew Kam
Published: January 2021

Binding energies, oscillator strengths, and polarizabilities of hydrogen-like atoms embedded in dense quantum plasmas are calculated in high precision by employing the generalized pseudospectral method. Benchmark predictions of these quantities are obtained for both the ground and excited states including high-order transitions. The critical behaviour of system eigenenergies, radial mean values, oscillator strengths, and multipole polarizabilities for bound states when they approach to the corresponding continuum limit as increasing the plasma screening strength are investigated in detail. It is shown that near the critical screening parameters the quantities in s-wave states show distinct behaviour from those in non-s states and such phenomenon is attributed to the divergent asymptotic form of wave functions caused by the centrifugal potential of orbital angular momentum. Based on the power laws of energies and radial mean values extracted from numerical calculations and the approximate formulae for dipole polarizabilities, the critical behaviour of the 2
k
-pole polarizability of s-wave states is explicitly derived and numerically validated to follow a power law with the exponent −2(k + 1).
Introducing an effective method for extending the high harmonic spectrum plateau from gas targets
Authors: Khodabandeh Z , Monfared M , Ara M H Majles , Sadighi-Bonabi R
Published: January 2021

An effective semi-classical method is introduced for controlling the high-order harmonic generation process and extending the cutoff frequency. This method is capable of defining the proper specification of the driving laser for maximizing the cutoff frequency. This method is evaluated by examining the high harmonic spectrum from the hydrogen atom and the fluorine (F2) molecule irradiated by single-, two-, and three-color laser fields. This study is done using the time-dependent density functional theory in a three-dimensional space. The results show that the single-, two-, and three-color laser pulses tuned by proper specifications could extend the cutoff frequency by up to 85%, 176%, and 241% compared to their non-tuned forms, respectively. Also, single attosecond pulses with a duration of 161 as and 129 as are obtained by applying the tuned three-color laser for the hydrogen atom and the fluorine molecule, respectively.
The role of radio frequency scattering in high-energy electron losses from minimum-B ECR ion source
Authors: Izotov I V , Shalashov A G , Skalyga V A , Gospodchikov E D , Tarvainen O , Mironov V E , Koivisto H , Kronholm R , Toivanen V , Bhaskar B
Published: January 2021

The measurement of the axially lost electron energy distribution escaping from a minimum-B electron cyclotron resonance ion source in the range of 4–800 keV is reported. The experiments have revealed the existence of a hump at 150–300 keV energy, containing up to 15% of the lost electrons and carrying up to 30% of the measured energy losses. The mean energy of the hump is independent of the microwave power, frequency and neutral gas pressure but increases with the magnetic field strength, most importantly with the value of the minimum-B field. Experiments in pulsed operation mode have indicated the presence of the hump only when microwave power is applied, confirming that the origin of the hump is radio-frequency-induced momentum space diffusion. A possible mechanism of the hump formation is considered based on the quasi-linear model of plasma–wave interaction.
Flow in an hourglass: particle friction and stiffness matter
Authors: Pongó Tivadar , Stiga Viktória , Török János , Lévay Sára , Szabó Balázs , Stannarius Ralf , Hidalgo Raúl Cruz , Börzsönyi Tamás
Published: January 2021

Granular flow out of a silo is studied experimentally and numerically. The time evolution of the discharge rate as well as the normal force (apparent weight) at the bottom of the container is monitored. We show that particle stiffness has a strong effect on the qualitative features of silo discharge. For deformable grains with a Young modulus of about Y
m ≈ 40 kPa in a silo with basal pressure of the order of 4 kPa, lowering the friction coefficient leads to a gradual change in the discharge curve: the flow rate becomes filling height dependent, it decreases during the discharge process. For hard grains with a Young modulus of about Y
m ≈ 500 MPa the flow rate is much less sensitive to the value of the friction coefficient. Using DEM data combined with a coarse-graining methodology allows us to compute all the relevant macroscopic fields, namely, linear momentum, density and stress tensors. The observed difference in the discharge in the low friction limit is connected to a strong difference in the pressure field: while for hard grains Janssen-screening is effective, leading to high vertical stress near the silo wall and small pressure above the orifice region, for deformable grains the pressure above the orifice is larger and gradually decreases during the discharge process. We have analyzed the momentum balance in the region of the orifice (near the location of the outlet) for the case of soft particles with low friction coefficient, and proposed a phenomenological formulation that predicts the linear decrease of the flow rate with decreasing filling height.
Tkwant: a software package for time-dependent quantum transport
Authors: Kloss Thomas , Weston Joseph , Gaury Benoit , Rossignol Benoit , Groth Christoph , Waintal Xavier
Published: January 2021

Tkwant is a Python package for the simulation of quantum nanoelectronics devices to which external time-dependent perturbations are applied. Tkwant is an extension of the kwant package (https://kwant-project.org/) and can handle the same types of systems: discrete tight-binding-like models that consist of an arbitrary central region connected to semi-infinite electrodes. The problem is genuinely many-body even in the absence of interactions and is treated within the non-equilibrium Keldysh formalism. Examples of Tkwant applications include the propagation of plasmons generated by voltage pulses, propagation of excitations in the quantum Hall regime, spectroscopy of Majorana fermions in semiconducting nanowires, current-induced skyrmion motion in spintronic devices, multiple Andreev reflection, Floquet topological insulators, thermoelectric effects, and more. The code has been designed to be easy to use and modular. Tkwant is free software distributed under a BSD license and can be found at https://tkwant.kwant-project.org/.
2D self-interacting magnetically confined electrons
Authors: Bruce S A , Diaz-Valdes J F
Published: January 2021

We investigate the nonlinear dynamics of electrons in the presence of an external homogeneous magnetic field in 2 + 1 flat space-time dimensions. Two regimes of magnetic fields are examined: high laboratory fields and strong-QED fields. We provide the (nonlinear) ground-state Landau energy levels together with their respective eigenfunctions. We comment on the relevance of this (toy) model to reveal certain processes thought to occur near the surfaces of neutron stars.
Electrical conductivity of a thin film in the case of an arbitrarily oriented ellipsoidal isoenergetic surface of a conductor
Authors: Kuznetsova I A , Romanov D N , Savenko O V
Published: January 2021

The static electrical conductivity of a thin conducting film is calculated using the kinetic approach. The model of diffuse boundary conditions is used as boundary conditions for the charge carrier distribution function. The isoenergetic surface of the conducting film material is an ellipsoid of rotation that is arbitrarily oriented in the pulse space. The volume of the conductor is dominated by scattering on impurity atoms and on dislocations of electrons (holes). The electrical conductivity of the film is analyzed depending on the angles that determine the direction of the ellipsoid axis of rotation, and a comparison with the results for the case of a macroscopic sample is presented. A comparison is made with experimental data for the electrical conductivity of Bi and Si thin films.
Entropy scrutiny of couple stress nanoliquid flow with slip and convective conditions in an upright microchannel
Authors: B J Gireesha , Venkatesh P , F Almeida
Published: January 2021

This article delves into the steady flow of couple stress nanoliquid by applying the magnetic field in conjunction with the resultant entropy produced in an upright microchannel which is immersed with Titanium-dioxide nano-sized particles with water being base fluid. Both the walls facilitate injection and suction of the fluid. The entropy generated and Bejan number is figured out by making use of velocity and temperature profiles. The coalesce sequel of nanoparticle volume fraction, magnetic field, linear thermal radiation and buoyancy force along with heat source/sink are taken into account. The equations governing the fluid flow are formulated under the impact of viscous dissipation and the numerical computations of the non-linear equations are made by using the shooting technique together with Runge–Kutta–Fehlberg fourth-fifth scheme. The effect of the viscous dissipation, Grashof number, Hartmann number and couple stress parameter on nanoliquid flow and thermal distributions are thrashed out and exposed graphically. The results indicate that peak values of couple stress parameter diminishes the velocity, temperature and entropy profile whereas amplifies the Bejan number. Also lower values of Hartmann number and nanoparticle volume fraction promotes the flow and higher values of heat source parameter and Peclet number exhibits augmentation in the thermal profile.
Interplay between neutrino and gravity portals for FIMP dark matter
Authors: Chianese Marco , Fu Bowen , King Stephen F.
Published: January 2021

In the classic type I seesaw mechanism with very heavy right-handed (RH) neutrinos, it is possible to account for dark matter via RH neutrino portal couplings to a feebly interacting massive particle (FIMP) dark sector. However, for large RH neutrino masses, gravity can play an important role. We study the interplay between the neutrino portal through the right-handed neutrinos and the gravity portal through the massless spin-2 graviton in producing dark matter particles in the early universe. As a concrete example, we consider the minimal and realistic Littlest Seesaw model with two RH neutrinos, augmented with a dark scalar and a dark fermion charged under a global U(1)_D dark symmetry. In the model, the usual seesaw neutrino Yukawa couplings and the right-handed neutrino masses (the lightest being about 5× 10^10 GeV) are fixed by neutrino oscillations data and leptogenesis. Hence, we explore the parameter space of the two RH neutrino portal couplings, the two dark particle masses and the reheating temperature of the universe, where the correct dark matter relic abundance is achieved through the freeze-in mechanism. In particular, we highlight which class of processes dominate the dark matter production. We find that, despite the presence of the gravity portal, the dark matter production relies on the usual seesaw neutrino Yukawa coupling in some regions of the parameter space, so realising a direct link between dark matter and neutrino phenomenology. Finally, we report the threshold values for the neutrino portal couplings below which the neutrino portal is irrelevant and the Planckian Interacting Dark Matter paradigm is preserved.
Terminal-optimized 700-V LDMOS with improved breakdown voltage and ESD robustness*
Authors: Xu Jie , He Nai-Long , Liang Hai-Lian , Zhang Sen , Jiang Yu-De , Gu Xiao-Feng
Published: January 2021

A novel terminal-optimized triple RESURF LDMOS (TOTR-LDMOS) is proposed and verified in a 0.25-μm bipolar-CMOS-DMOS (BCD) process. By introducing a low concentration region to the terminal region, the surface electric field of the TOTR-LDMOS decreases, helping to improve the breakdown voltage (BV) and electrostatic discharge (ESD) robustness. Both traditional LDMOS and TOTR-LDMOS are fabricated and investigated by transmission line pulse (TLP) tests, direct current (DC) tests, and TCAD simulations. The results show that comparing with the traditional LDMOS, the BV of the TOTR-LDMOS increases from 755 V to 817 V without affecting the specific on-resistance (R
on,sp) of 6.99 Ω⋅mm2. Meanwhile, the ESD robustness of the TOTR-LDMOS increases by 147%. The TOTR-LDMOS exhibits an excellent performance among the present 700-V LDMOS devices.
Speech stream segregation to control an ERP-based auditory BCI
Authors: Velasco-Álvarez Francisco , Fernández-Rodríguez Álvaro , Medina-Juliá M Teresa , Ron-Angevin Ricardo
Published: January 2021

Objective. The use of natural sounds in auditory brain–computer interfaces (BCI) has been shown to improve classification results and usability. Some auditory BCIs are based on stream segregation, in which the subjects must attend one audio stream and ignore the other(s); these streams include some kind of stimuli to be detected. In this work we focus on event-related potentials (ERP) and study whether providing intelligible content to each audio stream could help the users to better concentrate on the desired stream and so to better attend the target stimuli and to ignore the non-target ones. Approach. In addition to a control condition, two experimental conditions, based on the selective attention and the cocktail party effect, were tested using two simultaneous and spatialized audio streams: (a) the condition A2 consisted of an overlap of auditory stimuli (single syllables) on a background consisting of natural speech for each stream, (b) in condition A3, brief alterations of the natural flow of each speech were used as stimuli. Main results. The two experimental proposals improved the results of the control condition (single words as stimuli without a speech background) both in a cross validation analysis of the calibration part and in the online test. The analysis of the ERP responses also presented better discriminability for the two proposals in comparison to the control condition. The results of subjective questionnaires support the better usability of the first experimental condition. Significance. The use of natural speech as background improves the stream segregation in an ERP-based auditory BCI (with significant results in the performance metrics, the ERP waveforms, and in the preference parameter in subjective questionnaires). Future work in the field of ERP-based stream segregation should study the use of natural speech in combination with easily perceived but not distracting stimuli.
Radial electric field and density fluctuations measured by Doppler reflectometry during the post-pellet enhanced confinement phase in W7-X
Authors: Estrada T. , Carralero D. , Windisch T. , Sánchez E. , García-Regaña J.M. , Martínez-Fernández J. , de la Peña A. , Velasco J.L. , Alonso J.A. , Beurskens M. , Bozhenkov S. , Damm H. , Fuchert G. , Kleiber R. , Pablant N. , Pasch E. , W7-X team the
Published: January 2021

Radial profiles of density fluctuations and the radial electric field, E
r, have been measured using Doppler reflectometry during the post-pellet enhanced confinement phase achieved, under different heating power levels and magnetic configurations, during the 2018 W7-X experimental campaign. A pronounced E
r-well is measured with local values as high as −40 kV m−1 in the radial range ρ ∼ 0.7–0.8 during the post-pellet enhanced confinement phase. The maximum E
r intensity scales with both the plasma density and electron cyclotron heating power level, following a similar trend to the plasma energy content. A good agreement is found when the experimental E
r profiles are compared to simulations carried out using the neoclassical codes, the drift kinetic equation solver (DKES) and kinetic orbit-averaging solver for stellarators (KNOSOS). The density fluctuation level decreases from the plasma edge toward the plasma core and the drop is more pronounced in the post-pellet enhanced confinement phase than in reference gas-fuelled plasmas. Besides, in the post-pellet phase, the density fluctuation level is lower in the high iota magnetic configuration than in the standard one. To determine whether this difference is related to the differences in the plasma profiles or to the stability properties of the two configurations, gyrokinetic simulations have been carried out using the codes stella and EUTERPE. The simulation results point to the plasma profile evolution after the pellet injection and the stabilization effect of the radial electric field profile as the dominant players in the stabilization of the plasma turbulence.
Regime searching in time series data using Variational Autoencoder
Authors: Prosvetov Artem
Published: January 2021

In the current work we propose a method to extract regimes from time series using unsupervised learning. The proposed method is based on neural network with architecture of variational autoencoder and clusterization in latent space. The method has been proven by extracting regimes from a steam turbine telemetry data set and from human activity recognition data, which suggests that the proposed approach can extract regimes from time series data obtained for different areas.
Diffusion Model for Forecasting Events in News Feeds
Authors: Zhukov Dmitriy , Andrianova Elena , Novikova Olga
Published: January 2021

On the basis of the diffusion theory, we suggested a model for forecasting event in news feeds, which is based on the use of stochastic dynamics of changes in the structure of non-stationary time series in news text clusters (states of the information space). Forecasting events in a news feed is based on their text description, vectorization, and finding the cosine value of the angle between the given vector and the centroids of various information space semantic clusters. Changes over time in the cosine value of such angle between the above vector and centroids can be represented as a point wandering on [0,1] segment. This segment contains a trap at the event occurrence threshold point. The wandering point can fall into this trap over time. We have considered probability patterns of transitions between states in the information space. We have derived a nonlinear second-order differential equation; formulated and solved the boundary value problem of forecasting news events. We have obtained theoretical time dependence for the probability density function of the parameter distribution of non-stationary time series that describe the information space evolution. The results of simulating the time dependence of the event probability (with sets of parameter values of the developed model, which have been experimentally determined for already occurred events) show that the model is consistent and adequate. Experimental verification of the proposed model was carried out using a corpus of texts written in Russian.
Predicting nonverbal intelligence level from resting-state connectivity: a neural networks approach
Authors: Ivanov S A , Zakharov I M , Feklicheva I V , Ismatullina V I , Chipeeva N A , Alkapov R R , Bessonov V V , Buraya A A , Starkov A E , Malykh S M
Published: January 2021

This article is devoted to the development of a model of an artificial neural network for predicting the level of nonverbal intelligence according to the EEG of the brain. Cognitive functioning relies on the synchronization between different brain structures. However, it is still unclear how individual differences in intelligence are related to the global characteristics of information transmission in brain networks. Resting-state functional connectivity studies show the association of patterns of interactions between brain regions from people and different levels of nonverbal intelligence. In this study, we present a process of development of a neural network model used to predict the level of nonverbal intelligence based on EEG data of the brain. We have developed a fully-connected neural network to predict the level of nonverbal intelligence.
Cluster approach to analysis of publication titles
Authors: Bogomolova Arina , Ryazanova Maria , Balk Igor
Published: January 2021

Text analysis is a promising field of study with many unsolved problems. First of all, most methods are labor and time consuming. We want to pay special attention to patents. The most important thing in analyzing patents as a reflection of a company’s research activities is not to be late. Technology is emerging very quickly. So speed of response to changes in the world of scientific research is very important now. Therefore, we propose an alternative method of patent analysis based on clustering. Its main advantage is that it does not require different train/test datasets and it could be applied immediately. In this article, we compare different clustering algorithms, because the quality of the conclusions depends on it.
Inspection of corrosion defects of steel pipes by eddy current method
Authors: Ishkov A V , Dmitriev S F , Katasonov A O , Fadeev D A , Malikov V N
Published: January 2021

The article describes the results of testing a known non-destructive eddy current inspection method intended for non-destructive testing of steel pipelines. The analysis of the operational capabilities and features of this type of test objects showed the need for the development of new approaches in the field of creation of measuring sensors and software-hardware systems for pipelines’ technical inspection. The feasibility of creation of a measuring system capable of searching for defects with the diameters from 0.2 mm located at a depth of 2 mm is demonstrated. In the proposed method and its schematic design, the impact of a defect on the magnitude of the transformer EMF induced in the measuring winding of the eddy-current sensor is used. The article investigates the influence of the size and depth of the defect on the eddy-current sensor EMF and analyzes the influence of these parameters on the obtained signal dependences in order to determine the defect parameters.
Physical work principles of digital computational synthesizers of multiphase signals
Authors: Ryabov I V , Nikitin P V , Bazhenov R I , Kurileva N V , Gorokhova R I
Published: January 2021

Modern systems of radio engineering systems are very widely used in radar and radio communications. An important component of the work of radio systems is the creation of diagnostic equipment with high resolution, noise immunity, improved security and reliability, which become more accessible with the advent of digital computer frequency synthesizers. Digital computer synthesizers using the direct digital signal synthesis method are the main nodes of modern diagnostic equipment for radar and radio communication systems. The article considers a number of advantages of digital computing synthesizers, which include a wide range of synthesized frequencies, an extremely small step of the frequency grid, extremely fast frequency tuning speed, phase continuity during frequency tuning, low phase noise, a simple algorithm for generating complex signals, the possibility of independent amplitude control, phase and frequency of the synthesized signal. The principles of construction and structural and circuitry solutions of digital computational synthesizers based on the method of direct digital synthesis of frequencies and signals are given. The principle of constructing structures of digital multiphase signal synthesizers is proposed, in which the initial phases of the synthesized signals can be set in software. Structural diagrams of digital computational synthesizers based on digital code storage devices and with an M-shaped law of frequency variation which allow synthesizing signals with amplitude, frequency and phase modulation in the frequency range from 0.001 to 400 MHz are presented.
Using high accuracy geodetic measurements to fix the main bases of the ship in shipbuilding and ship-repairing
Authors: Palkin P O , Kuzin A A
Published: January 2021

The article presents the coordinate method of determination and fixes the courses of main bases of the ship. All the methods that are used according to regulatory documents were analyzed, and their advantages and drawbacks were described. The real measurements were made using a total station and a laser tracker. The accuracy of this method was determined. Based on this analysis, it was concluded that surveying methods, among others, could be used to fix the course of main bases of the ship.
Optimization of transient well test technology for low permeability complex reservoir
Authors: Palyanitsina A N , Akhmedova A N
Published: January 2021

This paper summarizes the experience of conducting hydrodynamic studies on transient filtration modes (pressure build up method) using an example of a low-permeable formation with a complex structure. Such objects are distinguished by a high degree of differentiation of reservoirs by filtration-capacitive properties, which affects the design of ongoing research. The relevance of the work is due to the need to justify the optimal research time for reservoirs with the considered properties in terms of obtaining high-precision data and minimizing oil production losses. In order to fulfill these tasks, it is urgent to develop a design for hydrodynamic research of wells. Research modeling was performed using the Kappa Saphir software product. The design will provide an integrated approach to modeling the process of conducting research and forecasting the data obtained. The design will optimize research time. Based on the calculation results, the duration of the effect of the wellbore effect and the time of the beginning of the boundary effect were analyzed. The reasons for the long exit to the pseudoradial flow regime were considered. In order to optimize the research process, an analysis of the error in determining the pressure was made, depending on the duration of the study. Taking into account the error, the optimal time for registering the PBU is proposed.
Designing of distributed systems of hydrolithosphere processes parameters control for the efficient extraction of hydromineral raw materials
Authors: Pershin I M , Kukharova T V , Tsapleva V V
Published: January 2021

Using methods developed for systems with distributed parameters allows us to optimize processes of hydromineral raw materials production in practice. In accordance with the theory of distributed systems, formation of control actions on each well of a complex of production wells requires taking into account a state of the entire complex of wells, which ensures better dynamics and accuracy of a control process. The methodology of constructing distributed control systems for controlling the entire complex of wells involves the use of dynamic and static characteristics of an exploited aquifer. In this connection, a problem of mathematical description (identification) of the processes under consideration arises, which can be realized, for example, using the methods and formulas of Theis-Jacob. Using the Theis-Jacob formulas for the identification of the processes under consideration assumes an availability of information about parameters of hydrolytosphere processes (piezoelectric conductivity, overflow coefficients, etc.). The calculation of the considered parameters is a rather laborious task. The article proposes a methodology for constructing approximation models of the processes under consideration based on experimental studies using 2 wells of a field. Based on the obtained approximation model, a synthesis of the system for the hydrolytosphere processes parameters control was implemented.
Application of qualimetric methods for assessing quality of complex products
Authors: Pudovkin O P
Published: January 2021

For the final product high-quality assessment in any application field, it is necessary to choose the optimal method and suitable measuring instruments for the right conditions. The paper reflects theoretical information about the atomic emission spectrometer, the advantages of using this device in the quantitative chemical analysis when monitoring surface waters. In addition, information on methods for evaluating such complex products as the atomic emission spectrometer is provided. The paper presents expert and mixed methods of qualimetry, describes their advantages and disadvantages. Based on them, a new method for evaluating the quality of the atomic emission spectrometer has been developed, which includes elements of the expert method, differential and complex, as well as a method for determining the consistency of experts. In addition, the methodology sets out requirements for experts who are members of the expert group. It is designed such factors as: individual and group weighting factor, assessment of the consistency of experts with the help of the coefficient of concordance, relative indicator of quality, the product quality level, the weighted average arithmetic. Based on the assessment of the last indicator, you can conclude that this product is better or worse than the basic one, or rank several products. Three atomic emission spectrometers were selected for testing this technique. One of them was selected as the base sample, with which the two evaluated samples were compared. They were ranked from best to worst, and their example shows the efficiency of this method.
Modelling of a hydroacoustic modem for underwater communications
Authors: Tokmachev D A , Chensky A G , Zolotarev N S , Poletaev A S
Published: January 2021

The paper discusses results of designing of an underwater communication device. The MSK modulation type is more preferable as it provides with narrow spectrum density of signals. The article describes a simulation program that allows one to model signal distortions and choose the best-fit method of detection. Three demodulation algorithms are tested. Simulation of signal propagating in underwater medium showed that the most effective is cross correlation detecting for which bit error rate was 5·10–4 at signal-to-noise ratio of 6 dB. Signal distortions were modelled with additive white noise, phase drift and superimposed re-reflections. For a piezoceramic antenna with a resonant frequency of 55 kHz and 6 kHz bandpass, the transmission frequencies of “0” and “1” are defined as 54 kHz and 56 kHz respectively, bitrate is 4000 bauds. During experimental testing in conditions of a natural reservoir all electronic devices demonstrated stability, the maximum range of reliable transmitting was 250 m.
Comparative assessment of documentation referred to surface roughness measurement
Authors: Vinogradova A A , Grichukha M I , Smirnova E E
Published: January 2021

The research relates to the field of metrological supervision, specifically to the control of surface roughness parameters. The authors analyzed the following regulatory documents: GOST R ISO 4287-2014 “Geometrical product specifications (GPS). Surface texture. Profile method. Terms, definitions and surface texture parameters”, GOST 25142-82 “Surface roughness. Terms and definitions”, GOST 2789-73 “Surface roughness. Parameters and characteristics”, GOST 9378-93 (ISO 2632-1-85, ISO 2632-2-85) “Roughness comparison specimens. General technical conditions”, GOST 27964-88 (ST SEV 6134-87, ISO 4287 / 2-84) “Measurement of roughness parameters. Terms and definitions”, GOST 19300-86 “Instruments for measurement of surface roughness by the profile method. Contact profilographs and profilometers. Types and main parameters”, GOST R 8.651-2009 ISO “State system for ensuring the uniformity of measurements. Contact (stylus) instruments for the measurement of surface roughness. Procedure of calibration”, GOST 9847-79 “Optical instruments for surface roughness parameters measuring. Basis parameters and types”, GOST R 8.700-2010 “State system for ensuring the uniformity of measurements. Method of surface roughness effective height measurements by means of scanning probe atomic force microscope”, which regulate the measured parameters of the surface roughness, instruments that measure these parameters. In the course of a comparative analysis of the values of the parameters of existing devices and the values of the parameters of devices prescribed in the standards, a summary table was formed, and the problem of controlling nanoparameters and nanocoatings was also identified. The existing instrument base for monitoring surface roughness allows measuring parameters with high accuracy and within wide limits, but the regulatory framework on the territory of the Russian Federation is outdated and does not allow the use of some modern types of instruments. In this regard, it is necessary to update the requirements of GOSTs for the modern capabilities of technology and control over roughness parameters.