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PubMed | Stanford University, SLAC and Center for Advancing Electronics Dresden
Type: Journal Article | Journal: Proceedings of the National Academy of Sciences of the United States of America | Year: 2015

With consumer electronics transitioning toward flexible products, there is a growing need for high-performance, mechanically robust, and inexpensive transparent conductors (TCs) for optoelectronic device integration. Herein, we report the scalable fabrication of highly conductive poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PSS) thin films via solution shearing. Specific control over deposition conditions allows for tunable phase separation and preferential PEDOT backbone alignment, resulting in record-high electrical conductivities of 4,600 100 S/cm while maintaining high optical transparency. High-performance solution-sheared TC PEDOT:PSS films were used as patterned electrodes in capacitive touch sensors and organic photovoltaics to demonstrate practical viability in optoelectronic applications.


Ceylan I.I.,TU Dresden | Penaloza R.,TU Dresden | Penaloza R.,Center for Advancing Electronics Dresden
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2014

We introduce the probabilistic Description Logic. In, axioms are required to hold only in an associated context. The probabilistic component of the logic is given by a Bayesian network that describes the joint probability distribution of the contexts. We study the main reasoning problems in this logic; in particular, we (i) prove that deciding positive and almost-sure entailments is not harder for than for the BN, and (ii) show how to compute the probability, and the most likely context for a consequence. © 2014 Springer International Publishing Switzerland.


Borgwardt S.,TU Dresden | Borgwardt S.,Center for Advancing Electronics Dresden | Penaloza R.,Center for Advancing Electronics Dresden
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2014

Abstract. We consider the fuzzy description logic ALCOI with semantics based on a finite residuated De Morgan lattice. We show that reasoning in this logic is ExpTime-complete w.r.t. general TBoxes. In the sublogics ALCI and ALCO, it is PSpace-complete w.r.t. acyclic TBoxes. This matches the known complexity bounds for reasoning in classical description logics between ALC and ALCOI. © Springer International Publishing Switzerland 2014.


Borchmann D.,TU Dresden | Borchmann D.,Center for Advancing Electronics Dresden
Lecture Notes in Artificial Intelligence (Subseries of Lecture Notes in Computer Science) | Year: 2015

Within formal concept analysis, attribute exploration is a powerful tool to semi-automatically check data for completeness with respect to a given domain. However, the classical formulation of attribute exploration does not take into account possible errors which are present in the initial data. To remedy this, we present in this work a generalization of attribute exploration based on the notion of confidence, that will allow for the exploration of implications which are not necessarily valid in the initial data, but instead enjoy a minimal confidence therein. © 2015 Springer International Publishing Switzerland.


Borgwardt S.,TU Dresden | Distel F.,TU Dresden | Penaloza R.,TU Dresden | Penaloza R.,Center for Advancing Electronics Dresden
Artificial Intelligence | Year: 2015

Fuzzy description logics (DLs) can be used to represent and reason with vague knowledge. This family of logical formalisms is very diverse, each member being characterized by a specific choice of constructors, axioms, and triangular norms, which are used to specify the semantics. Unfortunately, it has recently been shown that the consistency problem in many fuzzy DLs with general concept inclusion axioms is undecidable. In this paper, we present a proof framework that allows us to extend these results to cover large classes of fuzzy DLs. On the other hand, we also provide matching decidability results for most of the remaining logics. As a result, we obtain a near-universal classification of fuzzy DLs according to the decidability of their consistency problem. © 2014 Elsevier B.V. All rights reserved.


Weber W.M.,NaMLab gGmbH | Heinzig A.,NaMLab gGmbH | Heinzig A.,Center for Advancing Electronics Dresden | Trommer J.,NaMLab gGmbH | And 3 more authors.
IEEE Transactions on Nanotechnology | Year: 2014

Reconfigurable nanowire transistors are multifunctional switches that fuse the electrical characteristics of unipolar n- and p-type field effect transistors (FETs) into a single universal type of four-terminal device. In addition to the three known FET electrodes the fourth acts as an electric select signal that dynamically programs the desired polarity. The transistor consists of two independent charge carrier injection valves as realized by two gated Schottky junctions integrated within an intrinsic silicon nanowire. The transport properties that provide unipolar n- and p-type behavior will be elucidated. Further, solutions to the major device challenges toward the implementation of these novel transistors at the circuit level are proposed, by exploiting specific nanowire geometries and dimensions. These include methods that deliver equal on-currents and symmetric transfer characteristics for n- and p-type, and that eliminate supra-linear output characteristics at low source-drain biases. We will further show that circuits built of these symmetric transistors successfully exhibit complementary operation. Finally, the prospects in building reconfigurable circuits and systems will be briefly summarized. © 2002-2012 IEEE.


Mailis T.,TU Dresden | Penaloza R.,TU Dresden | Penaloza R.,Center for Advancing Electronics Dresden | Turhan A.-Y.,TU Dresden
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2014

Fuzzy Description Logics (DLs) generalize crisp ones by providing membership degree semantics for concepts and roles. A popular technique for reasoning in fuzzy DL ontologies is by providing a reduction to crisp DLs and then employ reasoning in the crisp DL. In this paper we adopt this approach to solve conjunctive query (CQ) answering problems for fuzzy DLs. We give reductions for Godel, and Łukasiewicz variants of fuzzy SROIQ and two kinds of fuzzy CQs. The correctness of the proposed reduction is proved and its complexity is studied for different fuzzy variants of SROIQ. © Springer International Publishing Switzerland 2014.


Borgwardt S.,TU Dresden | Penaloza R.,TU Dresden | Penaloza R.,Center for Advancing Electronics Dresden
International Journal of Approximate Reasoning | Year: 2014

Fuzzy Description Logics have been widely studied as a formalism for representing and reasoning with vague knowledge. One of the most basic reasoning tasks in (fuzzy) Description Logics is to decide whether an ontology representing a knowledge domain is consistent. Surprisingly, not much is known about the complexity of this problem for semantics based on complete De Morgan lattices. To cover this gap, in this paper we study the consistency problem for the fuzzy Description Logic L-SHI and its sublogics in detail. The contribution of the paper is twofold. On the one hand, we provide a tableaux-based algorithm for deciding consistency when the underlying lattice is finite. The algorithm generalizes the one developed for classical SHI. On the other hand, we identify decidable and undecidable classes of fuzzy Description Logics over infinite lattices. For all the decidable classes, we also provide tight complexity bounds. © 2013 Elsevier Inc.


Borgwardt S.,TU Dresden | Penaloza R.,TU Dresden | Penaloza R.,Center for Advancing Electronics Dresden
IJCAI International Joint Conference on Artificial Intelligence | Year: 2013

The Description Logic EL is used to formulate several large biomedical ontologies. Fuzzy extensions of EL can express the vagueness inherent in many biomedical concepts. We study the reasoning problem of deciding positive subsumption in fuzzy EL with semantics based on general t-norms. We show that the complexity of this problem depends on the specific t-norm chosen. More precisely, if the t-norm has zero divisors, then the problem is co-NP-hard; otherwise, it can be decided in polynomial time. We also show that the best subsumption degree cannot be computed in polynomial time if the t-norm contains the Łukasiewicz t-norm.


PubMed | TU Dresden and Center for Advancing Electronics Dresden
Type: Journal Article | Journal: Nano letters | Year: 2016

The conjunction of miniature nanosensors and droplet-based microfluidic systems conceptually opens a new route toward sensitive, optics-less analysis of biochemical processes with high throughput, where a single device can be employed for probing of thousands of independent reactors. Here we combine droplet microfluidics with the compact silicon nanowire based field effect transistor (SiNW FET) for in-flow electrical detection of aqueous droplets one by one. We chemically probe the content of numerous (10(4)) droplets as independent events and resolve the pH values and ionic strengths of the encapsulated solution, resulting in a change of the source-drain current ISD through the nanowires. Further, we discuss the specificities of emulsion sensing using ion sensitive FETs and study the effect of droplet sizes with respect to the sensor area, as well as its role on the ability to sense the interior of the aqueous reservoir. Finally, we demonstrate the capability of the novel droplets based nanowire platform for bioassay applications and carry out a glucose oxidase (GOx) enzymatic test for glucose detection, providing also the reference readout with an integrated parallel optical detector.

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