871 research outputs found
NatĂźrliche Arten, Wahrheit und der Raum der GrĂźnde
Ich mĂśchte eine Konzeption fĂźr zumindest eine Reihe von Termen fĂźr natĂźrliche Arten vorschlagen, die drei Elemente miteinander verbindet: Sie soll eine gewisse Bedeutungskonstanz dieser Terme Ăźber wissenschaftsgeschichtliche Entwicklungen hinweg implizieren; sie soll diese Konstanz auf eine Weise rekonstruieren, die es erlaubt, den Gehalt der Terme als Resultat diskursiver Prozesse (und nicht als etwas durch die Natur selbst strikt Festgelegtes) zu verstehen; und sie soll auf schwer einlĂśsbare Konzepte wie das âidealer rationaler Akzeptierbarkeitâ verzichten.
Die Semantik der Terme fĂźr natĂźrliche Arten ist u.a. deshalb wichtig, weil sie in einer engen Beziehung zum erkenntnistheoretischen Problem des Realismus und Antirealismus und zum Konzept der Wahrheit steht. Die hier skizzierte Auffassung erlaubt eine substantielle Unterscheidung zwischen Wahrheit und gerechtfertigter Ăberzeugung und ist insofern realistisch. FĂźr den hier verteidigten Wahrheitsbegriff spielen in gewisser Hinsicht metaphysische Konzepte wie die der Determination von Bedeutungen âdurch die Natur selbstâ oder der idealen rationalen Akzeptierbarkeit keine Rolle. Wichtig sind nur in wirklichen Diskursen diskutierbare GrĂźnde. Von daher liegt es nahe, von einem âdiskursiven Realismusâ zu sprechen.
Ich knĂźpfe dabei an eine ganze Reihe von Motiven an, die sich vor allem in Hilary Putnams Denken, z.T. aber auch bei Kripke und Burge finden, gebe ihnen dann aber doch eine andere Formung. Nach einer knappen Skizze der Problemlage erinnere ich deshalb kurz an etablierte Positionen, um dann daran anknĂźpfend meinen eigenen Vorschlag zu entwickeln
Startup of a reactive distillation process with a decanter
The startup of a reactive distillation process for the production of propyl acetate including a decanter is studied. A simulation model is presented which describes the whole startup from a cold and empty state and takes into account the liquid phase split in the decanter. The simulation model is successfully validated with own dynamic experimental data. Different startup strategies are developed and analysed in simulation studies showing the high influence of the initial charging of decanter and reboiler on the startup time
Deterministic Real-Time Tree-Walking-Storage Automata
We study deterministic tree-walking-storage automata, which are finite-state
devices equipped with a tree-like storage. These automata are generalized stack
automata, where the linear stack storage is replaced by a non-linear tree-like
stack. Therefore, tree-walking-storage automata have the ability to explore the
interior of the tree storage without altering the contents, with the possible
moves of the tree pointer corresponding to those of tree-walking automata. In
addition, a tree-walking-storage automaton can append (push) non-existent
descendants to a tree node and remove (pop) leaves from the tree. Here we are
particularly considering the capacities of deterministic tree-walking-storage
automata working in real time. It is shown that even the non-erasing variant
can accept rather complicated unary languages as, for example, the language of
words whose lengths are powers of two, or the language of words whose lengths
are Fibonacci numbers. Comparing the computational capacities with automata
from the classical automata hierarchy, we derive that the families of languages
accepted by real-time deterministic (non-erasing) tree-walking-storage automata
is located between the regular and the deterministic context-sensitive
languages. There is a context-free language that is not accepted by any
real-time deterministic tree-walking-storage automaton. On the other hand,
these devices accept a unary language in non-erasing mode that cannot be
accepted by any classical stack automaton, even in erasing mode and arbitrary
time. Basic closure properties of the induced families of languages are shown.
In particular, we consider Boolean operations (complementation, union,
intersection) and AFL operations (union, intersection with regular languages,
homomorphism, inverse homomorphism, concatenation, iteration). It turns out
that the two families in question have the same properties and, in particular,
share all but one of these closure properties with the important family of
deterministic context-free languages.Comment: In Proceedings NCMA 2023, arXiv:2309.0733
The Krupp Sponge Iron Process Production and Utilisation of Metallized Materials
Next to ore, fuel is the important factor governing the cost of producing primary iron.
In the blast furnace process, coke with special meta-llurgical properties is the basic source of heat. Its production requires the availability of coking coal. The direct reduction processes, conducted in rotary kilns, permit, however, the use of non-coking bituminous coal & anthracite and are capable of being fired with gas or oil if this appears to be appropriate
Relaxation of dynamically disordered tetragonal platelets in the relaxor ferroelectric
The local dynamics of the lead-free relaxor
(NBT-3.6BT) have been investigated by a combination of quasielastic neutron
scattering (QENS) and ab initio molecular dynamics simulations. In a previous
paper, we were able to show that the tetragonal platelets in the microstructure
are crucial for understanding the dielectric properties of NBT-3.6BT [F. Pforr
et al., Phys. Rev. B 94, 014105 (2016)]. To investigate their dynamics, ab
initio molecular dynamics simulations were carried out using
with 001 cation order as a
simple model system for the tetragonal platelets in NBT-3.6BT. Similarly,
111-ordered was used as a
model for the rhombohedral matrix. The measured single crystal QENS spectra
could be reproduced by a linear combination of calculated spectra. We find that
the relaxational dynamics of NBT-3.6BT are concentrated in the tetragonal
platelets. Chaotic stages, during which the local tilt order changes
incessantly on the timescale of several picoseconds, cause the most significant
contribution to the quasielastic intensity. They can be regarded as an excited
state of tetragonal platelets, whose relaxation back into a quasistable state
might explain the frequency dependence of the dielectric properties of
NBT-3.6BT in the 100 GHz to THz range. This substantiates the assumption that
the relaxor properties of NBT-3.6BT originate from the tetragonal platelets.Comment: 27 pages, 9 figure
A comment on the relation between diffraction and entropy
Diffraction methods are used to detect atomic order in solids. While uniquely
ergodic systems with pure point diffraction have zero entropy, the relation
between diffraction and entropy is not as straightforward in general. In
particular, there exist families of homometric systems, which are systems
sharing the same diffraction, with varying entropy. We summarise the present
state of understanding by several characteristic examples.Comment: 7 page
survey report
This report describes the set-up, logistics and results of the MEXAGE (Mexican Aero-Geophysical Survey) survey. It gives a short overview about the scientific intentions, detailed documentation of all technical aspects starting from the survey equipment via the aircraft installation to the GPS stations set-up to the experiences in flight. The processing results for the individual profiles are briefly discussed.repor
AI-enhanced diagnosis of challenging lesions in breast MRI: a methodology and application primer
Computer-aided diagnosis (CAD) systems have become an important tool in the assessment of breast tumors with magnetic resonance imaging (MRI). CAD systems can be used for the detection and diagnosis of breast tumors as a âsecond opinionâ review complementing the radiologistâs review. CAD systems have many common parts such as image pre-processing, tumor feature extraction and data classification that are mostly based on machine learning (ML) techniques. In this review paper, we describe the application of ML-based CAD systems in MRI of the breast covering the detection of diagnostically challenging lesions such as non-mass enhancing (NME) lesions, multiparametric MRI, neo-adjuvant chemotherapy (NAC) and radiomics all applied to NME. Since ML has been widely used in the medical imaging community, we provide an overview about the state-ofthe-art and novel techniques applied as classifiers to CAD systems. The differences in the CAD systems in MRI of the breast for several standard and novel applications for NME are explained in detail to provide important examples illustrating: (i) CAD for the detection and diagnosis, (ii) CAD in multi-parametric imaging (iii) CAD in NAC and (iv) breast cancer radiomics. We aim to provide a comparison between these CAD applications and to illustrate a global view on intelligent CAD systems based on ANN in MRI of the breast
Open Software Platform for Cyber-Physical Medical Systems
Abstract: Fail-safe open software platforms for cyber-physical medical systems (CPMS) are expected to securely host medical applications of medical devices, clinical systems and health repositories for the purpose of safe healthcare delivery to patients at the point of care. Secure and reliable ad-hoc connections to medical systems and health records are mandatory when health professionals need immediate access to the patient's live vital data and electronic medical records during individual medical procedures. Here, we report about a service-oriented open software platform that has been developed for cyber-physical networks of distributed medical systems. An automated data logging cyber-physical software system for medical procedures is described, which is characterized by secure user authorization, standardized device and system communication and softwareassisted guidance utilizing a WHO surgical safety checklist
- âŚ