bluuebunny/crossref_metadata_2025_split huggingface dataset:
Análise da Variabilidade Espaço-temporal da Topografia do Nível "Médio" do Mar a partir de Dados de Altimetria por Satélites e Estações da Rede Maregráfica Permanente para Geodésia
Authors: Souza Larissa Messias , Ferreira Ítalo Oliveira 
Published: August 2021

A técnica comumente aplicada para mensurar as variações locais do Nível “Médio” do Mar (NMM) e consequentemente da Topografia do Nível “Médio” do Mar (TNMM), têm sido a partir de uma abordagem geodésica, em que marégrafos são instalados na costa oceânica. No entanto, devido as dificuldades na manutenção de longas séries temporais, seja pela falta de recursos financeiros para instalação ou dificuldades técnicas para a instalação de marégrafos ou réguas linimétricas, vê-se como alternativa o emprego de dados por satélites altimétricos (ALTSAT). Diante disso, o presente estudo tem como objetivo propor uma metodologia para analisar as variações mensais da TNMM a partir de dados (ALTSAT) e de maregrafia, para este propósito, foi utilizada a missão CryoSat-2 (CS2) e os dados de maregrafia das estações EMFOR, EMSAL e EMIMB, todas pertencentes à Rede de Monitoramento Permanente para Geodésia (RMPG) no período de fevereiro de 2011 a setembro de 2019. Os resultados demostraram que a metodologia proposta é viável e pode ser empregada como complemento em dados maregráficos. Numa análise comparativa das variações locais da TNMM, verifica-se, no geral, que houve uma variação mais acentuada nos dados de maregrafia ao serem comparados com a ALTSAT, tal comportamento foi visível em todas as estações utilizadas, exceto em EMIMB, que apresentou maiores variações mensais na técnica de ALTSAT. Apesar do exposto, os resultados foram satisfatórios, explicitando uma discrepância anual entre as técnicas em todas as estações maregráficas na casa dos milímetros.
Estudio comparativo de diferentes métodos de análisis de validez de la muestra para la detección de drogas en orina: análisis de pH y densidad, tira de detección de adulterantes TECO™ y análisis de oxidantes
Authors: Mina Ashraf , Stathopoulos John , Sinanian Taveet , McNeice Leah , Holmes Deirdre , Fletcher Kristi-Lee , Bottero Emily , Banukumar Shanmugam , Vazquez Santiago 
Published: August 2021

Resumen

Objetivos
La adulteración de una muestra de orina por parte de un paciente puede pasar inadvertida si no se realiza una prueba de validez de la muestra. En este estudio se ha comparado el método análisis de densidad (SG, según acrónimo inglés), pH, la tira para detección de adulterantes TECO™ (Dipstick) y el análisis de oxidantes, para determinar las diferencias entre los mismos y permitir una toma de decisiones informada, a la hora de seleccionar un método.

Métodos
El análisis de la creatinina, la SG y el pH es esencial a la hora de realizar una prueba de validez de la muestra. Se compararon los métodos químicos automáticos de análisis de SG y pH con la potenciometría para el análisis de pH, la refractometría para el análisis de SG, y el método dipstick. Así mismo, se realizó una comparación entre el análisis de oxidantes y el método Dipstick.

Resultados
Se observó una concordancia del 81,9% y del 64,7% entre el método químico de análisis de SG y la refractometría y el método Dipstick, respectivamente. La concordancia entre la refractometría y Dipstick fue del 66,1%. La concordancia entre el método químico de análisis del pH y la potenciometría y el método Dipstick fue del 74,3% y del 81,4%, respectivamente. La concordancia entre la potenciometría y el método Dipstick fue del 85,7%. El análisis de resultados se realizó mediante el método de regresión de Deming y la prueba F. Los resultados demuestran una mejor correlación entre el método químico de análisis de SG y la refractometría, que con el método Dipstick. El análisis de oxidantes mostró una buena correlación con Dipstick a la hora de detectar adulterantes como el clorocromato de piridinio, el nitrito y la lejía.

Conclusiones
Se observaron diferencias en la medición de SG y pH. Dichas diferencias se deben tanto a factores metodológicos como instrumentales. Se recomienda el empleo de métodos químicos automatizados, así como del análisis de oxidantes debido a sus consistencia, precisión y mejor tiempo de respuesta para realizar la prueba de validez de la muestra para detectar la presencia de drogas.
Trajectory tracking of an omnidirectional mobile robot using Gaussian process regression
Authors: Eschmann Hannes , Ebel Henrik , Eberhard Peter 
Published: August 2021

Abstract
Mobile robots are enjoying increasing popularity in a number of different automation tasks. Omnidirectional mobile robots especially allow for a very flexible operation. They are able to accelerate in every direction, regardless of their orientation. In this context, we developed our own robot platform for research on said types of robots. It turns out that these mobile robots show interesting behaviour, which commonly used models for omnidirectional mobile robots fail to reproduce. As the exact sources and structures of mismatches are still unknown, non-parametric Gaussian process regression is used to develop a data-based model extension of the robot. A common control task for industrial applications is trajectory tracking, where a robot needs to follow a predefined path, for example in a warehouse, as close as possible in space and time. Appropriate feed-forward solutions for the data-based model are developed and finally leveraged in closed-loop control via nonlinear model predictive control. In real-world experiments, the results are compared to commonly used proportional position-based feedback. This novel contribution builds upon the preliminary work in [7] but, for the first time, includes also closed-loop (trajectory) tracking.
Distributed parameter modeling and model predictive control of weft insertion in air-jet weaving
Authors: Wu Tong , Huang Marvin , Ochudlo Patrick , Dörschel Lorenz , Kemper Maximilian , Abel Dirk , Gries Thomas 
Published: August 2021

Abstract
In air-jet weaving, the braking of inserted weft threads plays a significant role in fabric quality and machine productivity. This contribution presents Model Predictive Control (MPC) which controls the weft tip’s position and velocity with an optimal braking force. The inserted weft thread is firstly modeled as a distributed parameter system. The relation between the braking force and the weft tip’s position is described by a Partial Differential Equation (PDE). By analyzing the PDE with Laplace transform and solving the PDE with a Galerkin method, a state-space model is presented. Subsequently, identification experiments of the constructed yarn brake are performed and the whole model is analyzed as well as reduced using balanced truncation. Based on the system states and input disturbance estimated by a dual Kalman filter, an MPC controls the weft tip’s position and velocity appropriately without any backward movement. Regarding model deviations and simulated measurement errors, the MPC performs robustly.
Comparison of two model reduction approaches of an industrial drying process
Authors: Berner Marc Oliver , Mönnigmann Martin 
Published: August 2021

Abstract
Dynamic models have proven to be helpful for determining the residual water content in combustible biomass. However, these models often require partial differential equations, which render simulations impracticable when several thousand particles need to be considered, such as in the drying of wood chips. Reduced-order models help to overcome this problem. We compare proper orthogonal decomposition (POD) based to balanced truncation based reduced-order models. Both reduced models are lean enough for an application to systems with many particles, but the model based on balanced truncation shows more accurate results.
Kinetics study on reactive extraction of formic acid using tri-n-octyl amine diluted in n-butyl acetate
Authors: Shambharkar Dhiraj , Pal Dharm 
Published: August 2021

Abstract
Formic acid is the simplest yet commercially valuable organic acid. It is widely used as a stabilizer and sterile agent in food industries. Reactive extraction is highly effective and selective technique for the recovery of formic acid from dilute solutions. Kinetics study provide rate controlling step (reaction rate or diffusion) that is required to visualize the intrinsic reactive extraction mechanism. Kinetics study of formic acid (0.1–0.4 kmol/m3) extraction with tri-n-octyl amine (TOA) (0.11–0.67 kmol/m3) in n-butyl acetate (NBA) was investigated at temperature 308 ± 1 K. Kinetics study was carried out in a Lewis cell. Effect of formic acid concentration, TOA concentration, speed of stirring, and phase volume ratio were investigated to find the reaction regime. Diffusivity coefficient (DA) of formic acid in NBA was found 3.20 × 10−7 m2/s. Reaction rate constant was evaluated to be 0.616 m3/mol s. The physical mass transfer coefficient (kL) was evaluated to be 0.8278 × 10−6 × N
3.387. The reaction was independent on hydrodynamic parameters and falls under fast reaction regime. The reaction was found first order with respect to both formic acid as well as TOA, occurring in the diffusion film. The findings of the present work are helpful in the selection of commercially viable extraction system and in the design of extractors.
Design and operation of smart hybrid microgrid
Authors: Gupta Narayan Prasad , Paliwal Priyanka 
Published: August 2021

Abstract
Renewable energy resources based hybrid microgrid has emerged as a significant component of the power system. Nevertheless, the control and management of power, voltage and frequency under transition between grid-connected mode (GCM) and islanded mode (IM) is a major concern. This paper proposes a self-sustained and flexible novel cooperative control strategy (CCS) for smart hybrid microgrid (SHMG) under GCM and IM mode operations. In islanded operation of SHMG, conventional droop offers ease of control but its execution with seamless transition between operating modes poses poor voltage regulation and frequency deviation. For this purpose, an intelligent cooperative controller is proposed. It consists of a modified P/f-Q/V droop control (MDC) algorithm along with soft computing based VF-controller unit (VFCU). The proposed control scheme is implemented to regulate voltage and frequency. It also enhances the power quality with unbalanced non-linear load and source intermittencies. The absence of a communication link reduces cost and also eliminates the risk of single point breakdown. The SHMG has been simulated in MATLAB and implemented in real-time. The obtained experimental results demonstrate the competency and high robustness of the proposed scheme.
Efficient power scheduling in smart homes using a novel artificial ecosystem optimization technique considering two pricing schemes
Authors: Mouassa Souhil , Tostado-Véliz Marcos , Jurado Francisco 
Published: August 2021

Abstract
With emergence of automated environments, energy demand increased with unexpected ratio, especially total electricity consumed in the residential sector. This unexpected increase in demand in energy brings a challenging task of maintaining the balance between supply and demand. In this work, a robust artificial ecosystem-inspired optimizer based on demand-side management is proposed to provide the optimal scheduling pattern of smart homes. More precisely, the main objectives of the developed framework are: i) Shifting load from on-peak hours to off-peak hours while fulfilling the consumer intends to reduce electricity-bills. ii) Protect users comfort by improving the appliances waiting time. Artificial ecosystem optimizer (AEO) algorithm is a novel optimization technique inspired by the energy flocking between all living organisms in the ecosystem on earth. Demand side management (DSM) program is modeled as an optimization problem with constraints of starting and ending of appliances. The proposed optimization technique based DSM program is evaluated on two different pricing schemes with considering two operational time intervals (OTI). Extensive simulation cases are carried out to validate the effectiveness of the proposed optimizer based energy management scheme. AEO minimizes total electricity-bills while keeping the user comfort by producing optimum appliances scheduling pattern. Simulation results revealed that the proposed AEO achieved a minimization electricity-bill up to 10.95, 10.2% for RTP and 37.05% for CPP for the 12 and 60 min operational time interval (OTI), respectively, in comparison to other results achieved by other optimizers. On the other hand peak to average ratio (PAR) is reduced to 32.9% using RTP and 31.25% using CPP tariff.
New insights into singularity analysis
Authors: Halder Amlan K. , Paliathanasis Andronikos , Leach Peter G. L. 
Published: August 2021

Abstract
In this work, we emphasize the use of singularity analysis in obtaining analytic solutions for equations for which standard Lie point symmetry analysis fails to make any lucid decision. We study the higher-dimensional Kadomtsev–Petviashvili, Boussinesq, and Kaup–Kupershmidt equations in a more general sense. With higher-order equations, there can be a commensurate number of resonances and when consistency for the full equation is examined at each resonance the constant of integration is supposed to vanish from the expression so that it remains arbitrary, but if there is an instance of this not happening, the consistency can be partially established by giving the offending constant the value from the defining equation. If consistency is otherwise not compromised, the equation can be said to be partially integrable, i.e., integrable on a surface of the complex space. Furthermore, we propose an approach that is meant to magnify the scope of singularity analysis for equations admitting higher values for resonances or positive leading-order exponent.
Ovarian lesions and tumors in infants and older children
Authors: Fiegel Henning C. , Gfroerer Stefan , Theilen Till-Martin , Friedmacher Florian , Rolle Udo 
Published: August 2021

Abstract

Objectives
Ovarian lesions are rare but frequent in children. Patients could present with abdominal pain, but ovarian lesions could also be incidentally found on ultrasound. Awareness is required in cases with acute, severe lower abdominal pain, as ovarian torsion could be the cause. Other lesions can be cysts or benign or malignant ovarian tumors. Thus, the aim of this paper is to review typical ovarian lesions according to age, imaging and laboratory findings, and surgical management.

Methods
We retrospectively analysed the patient charts of 39 patients aged 10.4 ± 6.1 years (from 3 months to 18 years) with ovarian lesions treated in our institution between 01/2009 and 08/2020. All clinical and pathological findings of infants and children operated on for ovarian lesions were included.

Results
Ovarian lesions in children younger than 2 years of age were typically ovarian cysts, and ovarian tumors were not observed in this age group. In older children over 10 years of age, tumors were more common – with mostly teratoma or other germ cell tumors, followed by epithelial tumors. Moreover, acute or chronic ovarian torsion was observed in all age groups. In general, ovarian tumors were much larger in size than ovarian cysts or twisted ovaries and eventually showed tumor marker expression of AFP or ß-HCG. Simple ovarian cysts or twisted ovaries were smaller in size. Surgery for all ovarian lesions should aim to preserve healthy ovarian tissue by performing partial ovariectomy.

Conclusions
In adolescent girls with acute abdominal pain, immediate laparoscopy should be performed to rule out ovarian torsion. Careful imaging evaluation and the assessment of tumor markers should be performed in painless ovarian lesions to indicate an adequate surgical ovarian-sparing approach.
Towards a more objective time standard in competitive rowing
Authors: Kimmins Kenneth M. , Tsai Ming-Chang 
Published: August 2021

AbstractRowing needs a standardized Gold Medal Standard (GMS) to clearly compare performance across boat classes in competition. Here, we report a method to factor out environmental effects, developing a fairer GMS for individual rowing events. We used results from World Rowing Championships and Olympics Games (2005–2016) to calculate the difference between the fastest winning time of the day and other event winning times on the same day. From this, we calculated a prognostic GMS time for each event via repeated k-fold cross-validation linear regression. Then, we compared these values with the 10-year average winning time and the World Best Time (WBT). We repeated this process to develop prognostic podium standard (PS) times. The prognostic GMS times (RMSE = 9.47;R2= 0.875) were universally slower than the WBT (current GMS) by 6.2 s on average but faster than the 10-year average by 12.3 s. The prognostic PS times (RMSE = 10.5;R2= 897) were also slower than the WBT but faster than the 10-year average, by 12.2 and 6.3 s respectively. Our time-difference prediction model based on historical data generates non-outlier prognostic times. With the utilization of relative time difference, this approach promises a selection standard independent of environmental conditions, easily applicable across different sports.
Evaluation of the nanostructure of calcium silicate hydrate based on atomic force microscopy-infrared spectroscopy experiments
Authors: Zhu Zheyu , Wang Zhongping , Zhou Yue , Chen Yuting , Zhou Long , She Anming 
Published: August 2021

Abstract
Calcium silicate hydrate (C–S–H) is the main product of cement hydration, which forms the microstructure of cement via the stacking of basic nanocrystals or gel units, and has a substantial influence on the mechanical performance of cement. Tetrahedron chains of silicon oxide form the main nanoscale structure of basic C–S–H units. Evaluation on the nanostructure of these tetrahedron chains facilitates to understand the source of cement strength. This article first introduced the atomic force microscopy-infrared spectroscopy (AFM-IR) technique into evaluating the nanostructure of C–S–H. The nano infrared spectroscopy of stacking C–S–H nanograins and tetrahedron spatial distribution mapping was obtained. The results demonstrate that the relative quantity of tobermorite-like and jennite-like units in C–S–H nanograins can be analyzed by AFM-IR. The stacking between C–S–H particles is facilitated to a large extent by silicate (

SiO

4

2
−

{\text{SiO}}_{4}^{2-}

) tetrahedron chains formed of three tetrahedrons bridged by two oxygen atoms (i.e., Q2 chains), and there are Q2 chains acting as bridges between C–S–H particles. The proportions of different types of Q2 chains available for facilitating C–S–H particle stacking vary at the nanoscale. AFM-IR spatial mapping demonstrate that the orientations of these Q2 chains are not evenly distributed. These findings provide experimental information of the stacking C–S–H gaps.
Reflecting People’s Will: Evaluating elections with computer aided simulations
Authors: Verma Dhruv 
Published: August 2021

Abstract
The aim of this study is evaluate various single winner voting systems with the help of computer aided simulations. The impact of phenomena such as strategic voting, spoiler effect and centre squeeze are studied on various election systems such as First Past the Post, Ranked voting, Approval voting and Score voting. The democratic process gives great moral legitimacy to the winner as they are deemed to be chosen by the people, ergo the election system too needs to accurately reflect the will of all the people. Single winner systems or “winner takes all” systems have the advantage of decisive governments as compared to proportional systems but by its construct exclude parliamentary representation to a large percentage of voters who ended up on the losing side. It is therefore even more important that the single winner system mirror the voters mandate as accurately as possible. I conclude after evaluation that alternate systems such as Instant Runoff or Approval voting could be considered in lieu of the FPTP systems as they have fewer flaws and are more likely to give a truer representation of electorate’s choice.
“To Those Who Have Ears to Hear:” Clement of Alexandria on the Parables of Jesus
Authors: Vennerstrom Carl 
Published: August 2021

Abstract
This article addresses the topic of parables in the Stromateis of Clement of Alexandria. The broad thesis is that New Testament scholarship can help clarify early Christian interpretation of the New Testament. Clement of Alexandria has a very precise definition of the genre of parable. This definition is compared with various literary definitions found in the work of the grammarian Trypho of Alexandria and with one modern definition. Both of these comparisons bring out the precision, clarity, and usefulness of Clement’s definition for understanding the function of parables. The discussion then turns to the grounding of Clement’s definition in the saving mission of the Son. Since Clement closely links parables with prophecy and redemptive suffering, John Meier’s exposition of the Parable of the Wicked Tenants is introduced to show how parables can concretely express the redemptive suffering of the Son. Meier also demonstrates how the disciples were themselves involved in writing and completing this parable, so the article closes with an analysis of one of Clement’s interpretations of a parable, his own contribution to the tradition of parabolic speech.
Die Peloponnes in der mykenischen Palastzeit – wie „homogen“ war das Leben der Menschen in den einzelnen Regionen?
Authors: Mühlenbruch Tobias 
Published: August 2021

Zusammenfassung
Der längste Abschnitt der mykenischen „Palastzeit“, Späthelladisch III A2/B (ca. 1370–1200 v. Chr.), wird in der mykenischen Archäologie auch mit dem Begriff der „koiné“ bezeichnet, da uns die materiellen Hinterlassenschaften dieser Jahrzehnte als ausgesprochen homogen erscheinen. Mit diesem Beitrag wird dies für die Peloponnes kritisch und auf einer breiteren Quellenbasis hinterfragt. Dabei wird auf durchaus nicht zu unterschätzende Unterschiede in der materiellen Kultur dieser Zeit hingewiesen, die wiederum in Zusammenhang mit den Handlungen und Entscheidungen der Menschen in der damaligen Zeit gesehen werden müssen. Insgesamt wird dem Modell „homogenerer“ Verhältnisse, ausgehend von der materiellen Kultur, zugestimmt – im Vergleich mit unserem Bild der frühmykenischen Zeit sowie der Nachpalastzeit.
Die Wahrscheinlichkeit, von der materiellen Kultur ausgehend zwingende Rückschlüsse auf die politische Gliederung in der Vergangenheit, auf das konkrete Territorium eines „Staates“, auf Grenzverläufe etc. ziehen zu können, sei allerdings als sehr gering eingeschätzt.
The plastic of clothing and the construction of visual communication and interaction: a semiotic examination of the eighteenth-century French dress
Authors: Jardim Marilia 
Published: August 2021

Abstract
The article presents an account of the visual relations created by garments through their plastic formants, examining the role played by form, material, and composition in creating body hierarchies that produce prescribed behaviors between different subjects. The work dissects the concept of thematic role from Greimasian theory, investigating the manners in which an eighteenth-century wedding dress presents the chaining of programs governing materials, garments, and the body in the production of narrative interactions between subjects. The work utilizes a combination of Greimas’ method with the Visual Semiotics continued by Floch and Oliveira, as well as Hammad’s Semiotics of Space which permit the exam of optical relations created in the body through its clothing – relations that can be read as manifesting values that are both historically and socially determined, or in the act of apprehension of an object. The eighteenth century provides a type of “original” case, whose results are pertinent to a broader study of the relations between body and dress: the work concludes with the understanding that Fashion changes through the transit of values and roles invested in the body and dress – a set of changes closely linked to the construction of social roles.