bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sensitivity of the dynamic response of a multimegawatt floating wind turbine to the choice of turbulence model
Authors: Nybø Astrid , Gunnar Nielsen Finn , Godvik Marte 
Published: February 2022

AbstractIn the design of offshore wind turbines, it is important to make a realistic estimate of the wind load. This is particularly important for floating wind turbines, having natural frequencies in a frequency range where the wind loads are high and large turbulent structures exist. This study shows that turbulence modelling greatly impacts the response of a 15‐MW floating wind turbine. The turbulence models recommended by the International Electrotechnical Commission (IEC) are challenged by considering two additional models: Large Eddy Simulations (LES) and an approach using input from offshore wind measurements (TIMESR). The two standard models, the Kaimal spectrum with IEC coherence model (Kaimal) and the Mann spectral tensor model (Mann), differ in their coherence formulation. This results in higher standard deviations for the surge and pitch motions, and lower for the yaw motion, when applying Kaimal in comparison to Mann. For the specific floater of this study, more damage is obtained in the mooring lines when applying Kaimal. Applying the more realistic models, LES and TIMESR, increases the range of response further, concluding that the two standard turbulence models may lead to incorrect estimations of the response of a floating wind turbine. LES and TIMESR take atmospheric stability into account, which is proven to alter the response significantly.
Boundary Value Problems and Boundary Value Spaces
Authors: Seifert Christian , Trostorff Sascha , Waurick Marcus 
Published: February 2022

AbstractThis chapter is devoted to the study of inhomogeneous boundary value problems. For this, we shall reformulate the boundary value problem again into a form which fits within the general framework of evolutionary equations. In order to have an idea of the type of boundary values which make sense to study, we start off with a section that deals with the boundary values of functions in the domain of the gradient operator defined on a half-space in
$$\mathbb {R}^d$$

ℝ

d

(for d = 1 we have
$$L_2(\mathbb {R}^{d-1})=\mathbb {K}$$

L

2

(

ℝ

d
−
1

)
=
𝕂
).
Continuous Dependence on the Coefficients I
Authors: Seifert Christian , Trostorff Sascha , Waurick Marcus 
Published: February 2022

AbstractThe power of the functional analytic framework for evolutionary equations lies in its variety. In fact, as we have outlined in earlier chapters, it is possible to formulate many differential equations in the form
$$\displaystyle \left (\partial _{t}M(\partial _{t})+A\right )U=F. $$

∂

t

M
(

∂

t

)
+
A

U
=
F
.
Maximal Regularity
Authors: Seifert Christian , Trostorff Sascha , Waurick Marcus 
Published: February 2022

AbstractIn this chapter, we address the issue of maximal regularity. More precisely, we provide a criterion on the ‘structure’ of the evolutionary equation
$$\displaystyle \left (\overline {\partial _{t,\nu }M(\partial _{t,\nu })+A}\right )U=F $$

∂

t
,
ν

M
(

∂

t
,
ν

)
+
A

¯

U
=
F
in question and the right-hand side F in order to obtain
$$U\in \operatorname {dom}(\partial _{t,\nu }M(\partial _{t,\nu }))\cap \operatorname {dom}(A)$$

U
∈
dom
(

∂

t
,
ν

M
(

∂

t
,
ν

)

)

∩
dom
(
A
)
. If
$$F\in L_{2,\nu }(\mathbb {R};H)$$

F
∈

L

2
,
ν

(
ℝ
;
H
)
,
$$U\in \operatorname {dom}(\partial _{t,\nu }M(\partial _{t,\nu }))\cap \operatorname {dom}(A)$$

U
∈
dom
(

∂

t
,
ν

M
(

∂

t
,
ν

)

)

∩
dom
(
A
)
is the optimal regularity one could hope for. However, one cannot expect U to be as regular since
$$\left (\partial _{t,\nu }M(\partial _{t,\nu })+A\right )$$

∂

t
,
ν

M
(

∂

t
,
ν

)
+
A

is simply not closed in general. Hence, in all the cases where
$$\left (\partial _{t,\nu }M(\partial _{t,\nu })+A\right )$$

∂

t
,
ν

M
(

∂

t
,
ν

)
+
A

is not closed, the desired regularity property does not hold for
$$F\in L_{2,\nu }(\mathbb {R};H)$$

F
∈

L

2
,
ν

(
ℝ
;
H
)
. However, note that by Picard’s theorem,
$$F\in \operatorname {dom}(\partial _{t,\nu })$$

F
∈
dom
(

∂

t
,
ν

)
implies the desired regularity property for U given the positive definiteness condition for the material law is satisfied and A is skew-selfadjoint. In this case, one even has
$$U\in \operatorname {dom}(\partial _{t,\nu })\cap \operatorname {dom}(A)$$

U
∈
dom
(

∂

t
,
ν

)
∩
dom
(
A
)
, which is more regular than expected. Thus, in the general case of an unbounded, skew-selfadjoint operator A neither the condition
$$F\in \operatorname {dom}(\partial _{t,\nu })$$

F
∈
dom
(

∂

t
,
ν

)
nor
$$F\in L_{2,\nu }(\mathbb {R};H)$$

F
∈

L

2
,
ν

(
ℝ
;
H
)
yields precisely the regularity
$$U\in \operatorname {dom}(\partial _{t,\nu }M(\partial _{t,\nu }))\cap \operatorname {dom}(A)$$

U
∈
dom
(

∂

t
,
ν

M
(

∂

t
,
ν

)

)

∩
dom
(
A
)
since
$$\displaystyle \operatorname {dom}(\partial _{t,\nu })\cap \operatorname {dom}(A)\subseteq \operatorname {dom}(\partial _{t,\nu }M(\partial _{t,\nu }))\cap \operatorname {dom}(A)\subseteq \operatorname {dom}(\overline {\partial _{t,\nu }M(\partial _{t,\nu })+A}), $$

dom
(

∂

t
,
ν

)
∩
dom
(
A
)
⊆
dom
(

∂

t
,
ν

M
(

∂

t
,
ν

)

)

∩
dom
(
A
)
⊆
dom
(

∂

t
,
ν

M
(

∂

t
,
ν

)
+
A

¯

)
,
where the inclusions are proper in general. It is the aim of this chapter to provide an example case, where less regularity of F actually yields more regularity for U. If one focusses on time-regularity only, this improvement of regularity is in stark contrast to the general theory developed in the previous chapters. Indeed, in this regard, one can coin the (time) regularity asserted in Picard’s theorem as “U is as regular as F”. For a more detailed account on the usual perspective of maximal regularity (predominantly) for parabolic equations, we refer to the Comments section of this chapter.
Unbounded Operators
Authors: Seifert Christian , Trostorff Sascha , Waurick Marcus 
Published: February 2022

AbstractWe will gather some information on operators in Banach and Hilbert spaces. Throughout this chapter let X0, X1, and X2 be Banach spaces and H0, H1, and H2 be Hilbert spaces over the field
$$\mathbb {K}\in \{\mathbb {R},\mathbb {C}\}$$

𝕂
∈
{
ℝ
,
ℂ
}
.
„Intensive Care Unit-Acquired Weakness“
Authors: Klawitter Felix , Schaller Stefan J. , Söhle Martin , Reuter Daniel A. , Ehler Johannes 
Published: February 2022

Zusammenfassung
Hintergrund
Die „Intensive Care Unit-Acquired Weakness“ (ICU-AW) ist eine der häufigsten Ursachen für eine neuromuskuläre Dysfunktion in der Intensivmedizin. Gegenwärtig fehlen evidenzbasierte Empfehlungen zur Diagnostik, zum Monitoring und zu therapeutischen Maßnahmen.

Ziel der Arbeit
Die Erfassung des derzeitigen Vorgehens bei Diagnostik, Monitoring und präventiven und therapeutischen Ansätzen bei der ICU-AW auf deutschen Intensivstationen.

Material und Methoden
Onlinebefragung von 448 Mitgliedern des Wissenschaftlichen Arbeitskreises Intensivmedizin (WAKI) und des Wissenschaftlichen Arbeitskreises Neuroanästhesie (WAKNA).

Ergebnisse
Insgesamt wurden 68/448 (15,2 %) Fragebogen ausgewertet. Bei 13,4 % (9/67) der Befragten existiert ein strukturiertes diagnostisches Vorgehen zur Detektion der ICU-AW. Für Screening (60/68; 88,2 %) und Verlaufsbeurteilung (57/65; 87,7 %) wird die klinische Untersuchung präferiert. Etablierte Scores, wie der „Medical Research Council sum score“ (MRC-SS) spielen für Screening und Verlaufskontrolle der ICU-AW eine untergeordnete Rolle (7/68; 10,3 % und 7/65; 10,8 %). Mobilisation (45/68; 66,2 %) und Sedativareduktion (38/68; 55,9 %) stellen die häufigsten präventiven und therapeutischen Ansätze dar. Ein Mangel an Physiotherapeuten (64/68; 94,1 %) und Pflegekräften (57/68; 83,8 %) wird als Hauptdefizit bei der Versorgung von Patienten mit ICU-AW identifiziert. Insgesamt 91,2 % (62/68) der Befragten befürworten die Erstellung evidenzbasierter Empfehlungen zur Diagnostik, zum Monitoring und zu therapeutischen Ansätzen bei ICU-AW.

Diskussion
Ein einheitliches Konzept für Diagnostik, Monitoring, Prävention und Therapie der ICU-AW auf deutschen Intensivstationen fehlt weitgehend. Innovative diagnostische Ansätze könnten in Zukunft helfen, Patienten mit einem hohem Risiko für eine ICU-AW frühzeitig zu detektieren, präventive Maßnahmen einzuleiten sowie wertvolle prognostische Informationen zu gewinnen.
Spezialisierte ambulante Palliativversorgung für Kinder, Jugendliche und ihre Familien – die besonderen Belange der Zielgruppe. Ergebnisse der ELSAH-Studie
Authors: Engler Jennifer , Schütze Dania , Hach Michaela , Ploeger Cornelia , Engler Fabian ,   ELSAH-Studiengruppe, Ulrich Lisa-R. , Seipp Hannah , Kuss Katrin , Bösner Stefan , Haasenritter Jörg , Gerlach Ferdinand , Erler Antje 
Published: February 2022

Zusammenfassung
Hintergrund und Ziel
Lebenslimitierend erkrankte Kinder und Jugendliche mit komplexem Symptomgeschehen haben Anspruch auf eine spezialisierte ambulante Palliativversorgung (SAPV). In der Richtlinie zur SAPV heißt es lediglich: „Den besonderen Belangen von Kindern und Jugendlichen ist Rechnung zu tragen.“ Das Ziel der Studie ist es deshalb, diese besonderen Belange zu identifizieren und Empfehlungen zur Überarbeitung der SAPV-Richtlinie zu formulieren.

Methoden
Sequenzielles Mixed-Methods-Design mit Fragebogenerhebungen, qualitativen Interviews, teilnehmenden Beobachtungen und Fokusgruppendiskussionen mit Angehörigen, Patient*innen und Leistungserbringer*innen der SAPV in Hessen sowie der Auswertung von Dokumentationsdaten der hessischen SAPV-Teams.

Ergebnisse
Kinder und Jugendliche in der SAPV leiden an komplexen, oftmals seltenen Erkrankungen und bedürfen einer besonders aufwendigen Palliativversorgung durch ein Team mit pädiatrischer Expertise. Die SAPV muss die gesamte Familie einbeziehen und oftmals überregional verteilte Versorger*innen koordinieren. Zudem ist eine besonders aufwendige psychosoziale Versorgung von Patient*innen und Angehörigen notwendig. Die SAPV für Kinder und Jugendliche ist weniger bekannt als die SAPV für Erwachsene und der Zugang für die Familien deshalb oft schwierig. Für lebenslimitierend erkrankte Kinder und Jugendliche, die zwar einer aufsuchenden Palliativversorgung bedürfen, jedoch keinen Bedarf an einer so intensiven Betreuung wie in der SAPV haben, besteht eine Versorgungslücke.

Fazit
Die SAPV von Kindern und Jugendlichen sowie von volljährigen Patient*innen, die seit dem Kindes- und Jugendalter erkrankt sind, bedarf einer eigenständigen Versorgungsform mit Vergütungsmodalitäten, die den besonderen Versorgungsbedarf und -aufwand abbilden.
Binokulares Sehtraining bei Hochleistungssportlern
Authors: Kutzner Benedikt L. , Ring Matthias , Michelson Georg 
Published: February 2022

Zusammenfassung
Hintergrund und Fragestellung
Gutes Stereosehen scheint bei Hochleistungssportlern und im Alltag eine wichtige Rolle zu spielen. Wir untersuchten die Fragestellung, ob sich das Stereosehen bei Sportlern mit bereits guter Stereosehschärfe durch ein digitales Sehtraining noch verbessern kann.

Studiendesign und Untersuchungsmethoden
N = 31 männliche und weibliche Tennisspieler/innen absolvierten innerhalb 6 Wochen mindestens 6 Trainingseinheiten mit je 192 stereoskopischen Einzeltests mit variablem Schwierigkeitsgrad von 15 bis 300 Bogensekunden. Die Trainingsstimuli waren dynamischer, die Teststimuli statischer Natur. Zur Darstellung der Reaktionszeitverbesserung in Abhängigkeit des Schwierigkeitsgrades wurde der Parameter „ReSt“ (Reaktionszeitzuwachs pro Stereodisparitätsabnahme) bestimmt.

Ergebnisse
Die Reaktionszeit bei Stimuli von 15 Bogensekunden verkürzte sich durch das Sehtraining im Mittel signifikant von 3,9 s auf 1,6 s (59 %). Die Korrektheit der Versuche bei 30 Bogensekunden steigerte sich im Mittel signifikant um 23 %.

Diskussion
Die beobachtete Verbesserung der Reaktionszeit im Sehtraining führte nicht zur Abnahme der Korrektheit bei der Beantwortung der visuellen Fragen und stellt damit insgesamt eine Verbesserung der Stereosehfähigkeit dar.

Schlussfolgerung
Durch das digitale Sehtraining verbesserte sich das stereoskopische Sehen signifikant hinsichtlich Stereogrenzwinkel, Reaktionszeit und Korrektheit.
Test of cure and beyond: superiority of thermal ablation over LLETZ in the treatment of high-grade CIN
Authors: Armstrong G. M. , Ragupathy K. 
Published: February 2022

Abstract
Purpose
Among the treatment modalities for high-grade cervical intraepithelial neoplasia (CIN), large-loop excision of the transformation zone (LLETZ) is the commonest offered in the UK, whereas thermal ablation (TA) has not been common in several decades, despite several notable advantages. TA and LLETZ are both routinely undertaken in our colposcopy unit, and extensive follow-up data have been used to interrogate outcomes between the two modalities and determine whether one modality may be preferred over the other.

Methods
Up to 8 years of follow-up data (cytology and histology) were collected for patients who have undergone LLETZ or TA and failed post-treatment test of cure (ToC). These data were analysed and used to plot Kaplan–Meier survival curves, in order to compare outcomes: negative cytology, dyskaryosis, low- and high-grade CIN and invasive squamous cell carcinoma.

Results
i) Very few women treated with TA developed recurrent high-grade CIN in the follow-up period; (ii) LLETZ-treated women had a significantly higher rate of recurrence than those treated by TA; (iii) women who failed both virology and cytology components of post-treatment ToC had higher recurrence than those who failed only one, and the rate of recurrence was highest in those treated by LLETZ (> 65%).

Conclusion
TA is an effective treatment of high-grade CIN, with a high chance of achieving double-negative ToC and low recurrence relative to LLETZ. We recommend the wider adoption of TA, so that young women of reproductive age have a choice of treatment with no reported adverse effects on pregnancy outcomes.
Oxygen saturation-dependent effects on blood transverse relaxation at low fields
Authors: Thomas Dion G. , Galvosas Petrik , Tzeng Yu-Chieh , Harrison Freya G. , Berry Mary J. , Teal Paul D. , Wright Graham A. , Obruchkov Sergei 
Published: February 2022

AbstractObjectiveBlood oxygenation can be measured using magnetic resonance using the paramagnetic effect of deoxy-haemoglobin, which decreases the$$\textit{T}_{2}$$T2relaxation time of blood. This$$\textit{T}_{2}$$T2contrast has been well characterised at the$$\textit{B}_{{0}}$$B0fields used in MRI (1.5 T and above). However, few studies have characterised this effect at lower magnetic fields. Here, the feasibility of blood oximetry at low field based on$$\textit{T}_{2}$$T2changes that are within a physiological relevant range is explored. This study could be used for specifying requirements for construction of a monitoring device based on low field permanent magnet systems.MethodsA continuous flow circuit was used to control parameters such as oxygen saturation and temperature in a sample of blood. It flowed through a variable field magnet, where CPMG experiments were performed to measure its$$\textit{T}_{2}$$T2. In addition, the oxygen saturation was monitored by an optical sensor for comparison with the$$\textit{T}_{2}$$T2changes.ResultsThese results show that at low$$\textit{B}_{{0}}$$B0fields, the change in blood$$\textit{T}_{2}$$T2due to oxygenation is small, but still detectable. The data measured at low fields are also in agreement with theoretical models for the oxy-deoxy$$\textit{T}_{2}$$T2effect.Conclusion$$\textit{T}_{2}$$T2changes in blood due to oxygenation were observed at fields as low as 0.1 T. These results suggest that low field NMR relaxometry devices around 0.3 T could be designed to detect changes in blood oxygenation.
The mystery of unidentified infrared emission bands
Authors: Kwok Sun 
Published: February 2022

AbstractA family of unidentified infrared emission (UIE) bands has been observed throughout the Universe. The current observed spectral properties of the UIE bands are summarized. These properties are discussed in the frameworks of different models of the chemical carriers of these bands. The UIE carriers represent a large reservoir of carbon in the Universe, and play a significant role in the physical and chemical processes in the interstellar medium and galactic environment. A correct identification of the carrier of the UIE bands is needed to use these bands as probes of galactic evolution.
Echocardiographic assessment of intimal thickness growth of patent ductus arteriosus in neonates and analysis of influencing factors
Authors: Hu Xin-Lu , Wang Hui , Hou Cui , Hou Miao , Zhan Shi-Hong , Pan Tao , Ding Yue-Yue , Gu Pei-Pei , Xu Qiu-Qin 
Published: February 2022

AbstractThe spontaneous closure rate of patent ductus arteriosus (PDA) is high, and the necessity of early intervention is debated. Quantitative echocardiographic assessment of the intima in PDA has not been reported. This study evaluated intimal thickness growth in neonatal cases of PDA via echocardiography and investigated its correlation with clinical factors. Seventy-three neonates were enrolled, and echocardiography was performed three times: within 24 h post-birth (first echo), 48 h after the first echo (second echo), and before discharge (third echo). According to PDA outcome, the neonates were divided into the PDA-open group (n = 18 cases), PDA-closure at second echo group (n = 32 cases), and non-PDA at first echo group (n = 23 cases). We measured the intimal thickness (IT1 and IT2 at first and second echo, respectively), lumen diameter of ductus arteriosus (D1 and D2 at first and second echo, respectively), IT1/D1 ratio, and intimal thickness growth rate (V). Correlations between echocardiographic indicators, perinatal factors, and clinical treatment were analyzed. On first echo, the PDA-open group showed a significantly lower IT1/D1 than the combined PDA-closure group (P < 0.05). On second echo, the PDA-open group showed a significantly lower IT2 and V than the PDA-closure group as well as a significantly higher D2 (P < 0.05). Smaller gestational age correlated with a larger D2 but smaller IT2 and V (P < 0.05) and a higher level of respiratory support within 72 h post-birth correlated with a larger D2 and smaller IT 2 (P < 0.05). Increasing oxygen demand within 72 h of birth correlated with a larger D1 and D2 (P < 0.05). Echocardiographic assessment of intimal thickness growth in PDA may provide an approach for predicting spontaneous PDA closure, thereby guiding decision-making regarding early intervention.
The use of models and modelling in design projects in three different technology classrooms
Authors: Citrohn Björn , Stolpe Karin , Svensson Maria 
Published: February 2022

AbstractIn this study, we aim to investigate activities using models in a design project in three technology classrooms. Activities that use models are important for students’ development of knowledge and skills connected to the design process. Nevertheless, few empirical studies have thus far examined how models and modelling are used in a classroom environment when students and teachers are involved in a design project. In order to meet our aim, we video-recorded eight lessons from three different technology classrooms (students aged 13–15), where the students were involved in different problem-solving activities using models and modelling. The three projects had different specifications, and the students’ degrees of freedom thereby varied. The video recordings were analysed using a qualitative content analysis. The analysis resulted in seven activities being identified where the teachers and students talked about models and modelling in order to solve the problem. The results also revealed three different dimensions of models: material, structure and function. These dimensions are present in almost all activities that use models. In a project with a high degree of freedom, all three dimensions of models are present. On the contrary, in a project with a lower freedom, only one of the dimensions is present, resulting in a lower degree of complexity for the students. The study emphasizes that the presumptions and openness of a design project in technology education can provide different possibilities for students learning in relation to models and modelling.
Acoustic Response of Reference Notches: Derivation of Acceptance Criteria for Automated Ultrasonic Testing Based on the Correlation Between Defect Quality and Effective Defect Size
Authors: Würschig Thomas 
Published: February 2022

AbstractThis paper presents a detailed study of the acoustic response of artificially manufactured notches, which are established reference defects in common standards for ultrasonic testing (UT). Measurements were performed with standard tubes manufactured for the commissioning of automated UT machines. Included reference notches are at the inner and outer tube surface and have different lengths and orientations (longitudinal, oblique and transverse). From the acoustic reflection profile, i.e. the measured defect amplitude along the notch axis, the effective defect length and the defect homogeneity are introduced as measured quantities of the reference defect quality. The large data sample of 320 evaluated notch profiles gives insight to the statistics of the achieved reference defect quality. Key approach of the analysis is the correlation between both measured quantities. It reveals a universal behaviour, which can be described by a sigmoidal function converging for high quality defects towards the theoretical limits. Based on the obtained parametrization it is possible to define criterions for the required defect quality and the test speed as function of the specified repeatability. This solves the current dilemma how to distinguish between variations due to the reference quality from those related to the testing machine. Furthermore, the presented measurement procedure can be used for a reference certification, which complements existing standards for the ultrasonic system and the probes.
Scenic: a language for scenario specification and data generation
Authors: Fremont Daniel J. , Kim Edward , Dreossi Tommaso , Ghosh Shromona , Yue Xiangyu , Sangiovanni-Vincentelli Alberto L. , Seshia Sanjit A. 
Published: February 2022

AbstractWe propose a new probabilistic programming language for the design and analysis of cyber-physical systems, especially those based on machine learning. We consider several problems arising in the design process, including training a system to be robust to rare events, testing its performance under different conditions, and debugging failures. We show how a probabilistic programming language can help address these problems by specifying distributions encoding interesting types of inputs, then sampling these to generate specialized training and test data. More generally, such languages can be used to write environment models, an essential prerequisite to any formal analysis. In this paper, we focus on systems such as autonomous cars and robots, whose environment at any point in time is a scene, a configuration of physical objects and agents. We design a domain-specific language, Scenic, for describing scenarios that are distributions over scenes and the behaviors of their agents over time. Scenic combines concise, readable syntax for spatiotemporal relationships with the ability to declaratively impose hard and soft constraints over the scenario. We develop specialized techniques for sampling from the resulting distribution, taking advantage of the structure provided by Scenic’s domain-specific syntax. Finally, we apply Scenic in multiple case studies for training, testing, and debugging neural networks for perception both as standalone components and within the context of a full cyber-physical system.