Hardware prototyping is an essential part in the hardware design flow. Furthermore, hardware prototyping usually relies on system-level design and hardware-in-the-loop simulations in order to develop, test and evaluate intellectual property cores. One common task in this process consist on interfacing cores with different port specifications. Data width conversion is used to overcome this issue. This work presents two open source hardware cores compliant with AXI4-Stream bus protocol, where each core performs upsizing/downsizing data width conversion.
Recently convex optimization models were successfully applied
for solving various problems in image analysis and restoration.
In this paper, we are interested in relations between
convex constrained optimization problems
of the form
\({\rm argmin} \{ \Phi(x)\) subject to \(\Psi(x) \le \tau \}\)
and their penalized counterparts
\({\rm argmin} \{\Phi(x) + \lambda \Psi(x)\}\).
We recall general results on the topic by the help of an epigraphical projection.
Then we deal with the special setting \(\Psi := \| L \cdot\|\) with \(L \in \mathbb{R}^{m,n}\)
and \(\Phi := \varphi(H \cdot)\),
where \(H \in \mathbb{R}^{n,n}\) and \(\varphi: \mathbb R^n \rightarrow \mathbb{R} \cup \{+\infty\} \)
meet certain requirements which are often fulfilled in image processing models.
In this case we prove by incorporating the dual problems
that there exists a bijective function
such that
the solutions of the constrained problem coincide with those of the
penalized problem if and only if \(\tau\) and \(\lambda\) are in the graph
of this function.
We illustrate the relation between \(\tau\) and \(\lambda\) for various problems
arising in image processing.
In particular, we point out the relation to the Pareto frontier for joint sparsity problems.
We demonstrate the performance of the
constrained model in restoration tasks of images corrupted by Poisson noise
with the \(I\)-divergence as data fitting term \(\varphi\)
and in inpainting models with the constrained nuclear norm.
Such models can be useful if we have a priori knowledge on the image rather than on the noise level.
Modern society relies on convenience services and mobile communication. Cloud computing is the current trend to make data and applications available at any time on every device. Data centers concentrate computation and storage at central locations, while they claim themselves green due to their optimized maintenance and increased energy efficiency. The key enabler for this evolution is the microelectronics industry. The trend to power efficient mobile devices has forced this industry to change its design dogma to: ”keep data locally and reduce data communication whenever possible”. Therefore we ask: is cloud computing repeating the aberrations of its enabling industry?
We consider a variant of the generalized assignment problem (GAP) where the amount of space used in each bin is restricted to be either zero (if the bin is not opened) or above a given lower bound (a minimum quantity). We provide several complexity results for different versions of the problem and give polynomial time exact algorithms and approximation algorithms for restricted cases.
For the most general version of the problem, we show that it does not admit a polynomial time approximation algorithm (unless P=NP), even for the case of a single bin. This motivates to study dual approximation algorithms that compute solutions violating the bin capacities and minimum quantities by a constant factor. When the number of bins is fixed and the minimum quantity of each bin is at least a factor \(\delta>1\) larger than the largest size of an item in the bin, we show how to obtain a polynomial time dual approximation algorithm that computes a solution violating the minimum quantities and bin capacities by at most a factor \(1-\frac{1}{\delta}\) and \(1+\frac{1}{\delta}\), respectively, and whose profit is at least as large as the profit of the best solution that satisfies the minimum quantities and bin capacities strictly.
In particular, for \(\delta=2\), we obtain a polynomial time (1,2)-approximation algorithm.
We consider the maximum flow problem with minimum quantities (MFPMQ), which is a variant of the maximum flow problem where
the flow on each arc in the network is restricted to be either zero or above a given lower bound (a minimum quantity), which
may depend on the arc. This problem has recently been shown to be weakly NP-complete even on series-parallel graphs.
In this paper, we provide further complexity and approximability results for MFPMQ and several special cases.
We first show that it is strongly NP-hard to approximate MFPMQ on general graphs (and even bipartite graphs) within any positive factor.
On series-parallel graphs, however, we present a pseudo-polynomial time dynamic programming algorithm for the problem.
We then study the case that the minimum quantity is the same for each arc in the network and show that, under this restriction, the problem is still
weakly NP-complete on general graphs, but can be solved in strongly polynomial time on series-parallel graphs.
On general graphs, we present a \((2 - 1/\lambda) \)-approximation algorithm for this case, where \(\lambda\) denotes the common minimum quantity of all arcs.
Wir zeigen, dass Aleph-Null diejenige transfinite Kardinalzahl ist, gegen die alle Zahlenfolgen streben, die (nach gängiger Definition) gegen (positiv) unendlich streben, und beleuchten dessen Konsequenzen. Diese beinhalten u.a., dass die Exponentialfunktion im Unendlichen unstetig ist.
Die fortschreitende Verbreitung von Ethernet-basierten Strukturen mit dezentralen und verteilten Anwendungen in der Automatisierung führt zu den so genannten netzbasier-ten Automatisierungssystemen (NAS). Diese sind zwar in Anschaffung und Betrieb kostengünstiger, moderner und flexibler als herkömmliche Strukturen, weisen jedoch nicht-deterministische Verzögerungen auf. Die genaue Analyse der resultierenden Antwortzeiten ist somit nicht nur Voraussetzung für den verantwortungsbewussten Einsatz dieser Technologie sondern ermöglicht es auch, bereits im Vorfeld von Umstrukturierungen oder Erweiterungen, Fragen der Verlässlichkeit zu klären. In diesem ersten von zwei Beiträgen wird hierfür zunächst die für die speziellen Bedürfnisse der Strukturbeschreibung von netzbasierten Automatisierungssystemen entwickelte Modellierungssprache DesLaNAS vorgestellt und auf ein einführendes Beispiel angewendet. Im zweiten Beitrag wird darauf aufbauend gezeigt, welchen Einfluss die einzelnen System-komponenten (SPS, Netzwerk, I/O-Karten) sowie netzbedingte Verhaltensmodi wie Synchronisation und die gemeinsame Nutzung von Ressourcen auf die Antwortzeiten des Gesamtsystems haben. Zur Analyse selbst wird die wahrscheinlichkeitsbasierte Modellverifikation (PMC) angewendet.
Netzbasierte Automatisierungssysteme (NAS) sind das Ergebnis der zunehmenden Dezentralisierung von Automatisierungssystemen mittels neuerer Netzwerkstrukturen. Eine ganze Fülle von Einflussfaktoren führt jedoch zu einem Spektrum von nicht-deterministischen Verzögerungen, die direkten Einfluss auf Qualität, Sicherheit und Zuverlässigkeit der Automatisierungsanlagen haben. Eine genaue Analyse dieser Einflussfaktoren ist somit nicht nur Voraussetzung für den verantwortungsbewussten Einsatz dieser Technologie sondern ermöglicht es auch, bereits im Vorfeld von Umstrukturierungen oder Erweiterungen Fragen der Verlässlichkeit zu klären. In diesem Beitrag wird gezeigt, welchen Einfluss einzelne Komponenten sowie netzbedingte Verhaltensmodi wie Synchronisation und die gemeinsame Nutzung von Ressourcen auf die Antwortzeiten des Gesamtsystems haben. Zur Analyse wird die wahrscheinlichkeitsbasierte Modellverifikation (PMC) verwendet. Umfangreiche Messungen wurden zur Validierung der Ergebnisse durchgeführt.
In recent years, more and more publications and material for studying and teaching, e. g. for Web-based teaching (WBT), appear "online" and digital libraries are built to manage such publications and online materials. Therefore, the most important concerns are related to the problem of durable, sustained storage and the management of content together with its metadata existing in heterogeneous styles and formats. In this paper, we present specific techniques and their use to support metadata-based catalog services. Such semistructured metadata (represented as XML fragments), which belong to online learning resources, need efficient XML-based query support, scalable result set processing, and comprehensive facilities for personalization purposes. We discuss the associated problems, subsequently derive the concepts of a suitable architecture, and finally outline the realization by means of our prototype system that is based on the J2EE component model.
Ökonomische Auswirkungen und Imageeffekte des FCK für die Stadt Kaiserslautern
(2014)
