PIAF: a knowledge-based/algorithm top-down floorplanning system

Author(s):  
M. A. Jabri ◽  
D. J. Skellern
Keyword(s):  
Top Down ◽  
Author(s):  
M V Lihachev ◽  
I V Poturemsky ◽  
Yu G Vygonsky ◽  
A D Leonenkov ◽  
V V Baranov
Keyword(s):  
Top Down ◽  

Author(s):  
X.F. ZHA ◽  
H. DU

This paper presents a novel knowledge-based Petri net approach to mechanical systems and assemblies modeling within a design with objects environment. A new unified class of object-oriented knowledge Petri nets, which can incorporate a knowledge-based system with ordinary Petri nets, is defined and used for the unified representations of assembly design and modeling. The object knowledge Petri nets, as a graphical language and a new knowledge-based description scheme, can be used to express the qualitative and quantitative aspects of the assembly design and modeling process in an interactive and integrated way. The four-level hierarchy model is proposed and constructed in terms of function-behaviors, structures, geometries, and features. The function-behavior-structure description is built on more abstract concepts so that it can match well top-down design. The static and dynamic characteristics in the design of assembly can also be captured. With the help of fuzzy logic, the incomplete, imprecise knowledge and uncertainty in the design process can also be dealt with. Therefore, the hybrid design object model can incorporate product data model, top-down design process, and assembly process model using an object-oriented, knowledge-based, feature-based, parametric, and constraint-based modeling approach, and can provide a more accurate and more flexible representation. To verify and demonstrate the effective use of the proposed hybrid design object model, a prototype system has been developed. This research provides a knowledge-intensive framework for intelligent assembly design and modeling.


Author(s):  
Benoit Gaüzère ◽  
Pierluigi Ritrovato ◽  
Alessia Saggese ◽  
Mario Vento

2017 ◽  
Author(s):  
Nai Ding ◽  
Xunyi Pan ◽  
Cheng Luo ◽  
Naifei Su ◽  
Wen Zhang ◽  
...  

AbstractHow the brain sequentially groups sensory events into temporal chunks and how this process is modulated by attention are fundamental questions in cognitive neuroscience. Sequential grouping includes bottom-up primitive grouping and top-down knowledge-based grouping. In speech perception, grouping acoustic features into syllables can rely on bottom-up acoustic continuity cues but grouping syllables into words critically relies on the listener’s lexical knowledge. This study investigates whether top-down attention is required to apply lexical knowledge to group syllables into words, by concurrently monitoring neural entrainment to syllables and words using electroencephalography (EEG). When attention is directed to a competing speech stream or cross-modally to a silent movie, neural entrainment to syllables is weakened but neural entrainment to words largely diminishes. These results strongly suggest that knowledge-based grouping of syllables into words requires top-down attention and is a bottleneck for the neural processing of unattended speech.


2004 ◽  
Vol 63 (3) ◽  
pp. 143-149 ◽  
Author(s):  
Fred W. Mast ◽  
Charles M. Oman

The role of top-down processing on the horizontal-vertical line length illusion was examined by means of an ambiguous room with dual visual verticals. In one of the test conditions, the subjects were cued to one of the two verticals and were instructed to cognitively reassign the apparent vertical to the cued orientation. When they have mentally adjusted their perception, two lines in a plus sign configuration appeared and the subjects had to evaluate which line was longer. The results showed that the line length appeared longer when it was aligned with the direction of the vertical currently perceived by the subject. This study provides a demonstration that top-down processing influences lower level visual processing mechanisms. In another test condition, the subjects had all perceptual cues available and the influence was even stronger.


2003 ◽  
Vol 14 (3) ◽  
pp. 181-190 ◽  
Author(s):  
Walter Sturm

Abstract: Behavioral and PET/fMRI-data are presented to delineate the functional networks subserving alertness, sustained attention, and vigilance as different aspects of attention intensity. The data suggest that a mostly right-hemisphere frontal, parietal, thalamic, and brainstem network plays an important role in the regulation of attention intensity, irrespective of stimulus modality. Under conditions of phasic alertness there is less right frontal activation reflecting a diminished need for top-down regulation with phasic extrinsic stimulation. Furthermore, a high overlap between the functional networks for alerting and spatial orienting of attention is demonstrated. These findings support the hypothesis of a co-activation of the posterior attention system involved in spatial orienting by the anterior alerting network. Possible implications of these findings for the therapy of neglect are proposed.


2011 ◽  
Vol 22 (1) ◽  
pp. 21-32 ◽  
Author(s):  
Julia Graf ◽  
Hartwig Kulke ◽  
Christa Sous-Kulke ◽  
Wilfried Schupp ◽  
Stefan Lautenbacher
Keyword(s):  

Aufmerksamkeit kann als Kontrollsystem neuronaler Aktivität verstanden werden, welches Neuroplastizität top-down modulieren hilft. Bisher wurde selten versucht, durch deren gezielte Förderung Funktionswiederherstellungen nach Hirnschädigung zu begünstigen. In vorliegender Studie wurde dies am Beispiel der Aphasie erprobt. 15 Schlaganfallpatienten erhielten ein dreiwöchiges Training der selektiven Aufmerksamkeit mit den PC-Programmen CogniPlus und „Konzentration“ bei fünf Sitzungen pro Woche zusätzlich zur Standardtherapie, 13 weitere bildeten eine Kontrollgruppe ohne Aufmerksamkeitstraining. Zur Effektivitätskontrolle dienten zwei Versionen des Untertests Go/Nogo (Testbatterie zur Aufmerksamkeitsprüfung) und die Kurze Aphasieprüfung. Nach dem Training manifestierte sich zwischen den Untersuchungsgruppen kein Unterschied in Aufmerksamkeits- und Sprachfunktionen; das zusätzliche Aufmerksamkeitstraining war also wirkungslos. Allerdings zeigten Patienten mit deutlichen Aufmerksamkeitsverbesserungen tendenziell weniger Aphasie-Symptome, was die Hypothese aufmerksamkeitsvermittelter Plastizitätsmodulation nach Hirnschädigung partiell stützt.


2001 ◽  
Vol 209 (1) ◽  
pp. 34-53 ◽  
Author(s):  
Rainer Bösel
Keyword(s):  
Top Down ◽  

Zusammenfassung. Aufmerksamkeit wird sowohl als Selektivität in der bewußter Verarbeitung oder auch als selektive neuronale Aktivierung verstanden. Die neuronalen Strukturen, die Objektdiskrimination ermöglichen, erlauben eine Interaktion von datengetriebenen und endogenen top-down Prozessen, die zu einer selektiven Bereitstellung von Verarbeitungs-Ressourcen führen. Zielgerichtetes Verhalten erfordert manchmal einen Wechsel in der Ressourcen-Bereitstellung und eine Konzentration von mentaler Aktivität. Aufmerksamkeitswechsel kann als ein zweiphasiger Prozeß verstanden werden, der aus einer breiten Mobilisierung von Gedächtnis-Ressourcen besteht (angezeigt durch EEG-Theta), gefolgt von einer re-organisierenden Einengung neuronaler Aktivität (angezeigt durch langsames EEG-Alpha). Dieser Beitrag unterstützt die Annahme, daß die Analyse des gekoppelten Wechselspiels aus Mobilisierung und Konzentration in bestimmten Teilen der posterioren und anterioren Rindenregionen ein Schlüssel für das Verständnis von Aufmerksamkeitswechsel sein könnte.


2017 ◽  
Vol 38 (3) ◽  
pp. 133-143 ◽  
Author(s):  
Danny Osborne ◽  
Yannick Dufresne ◽  
Gregory Eady ◽  
Jennifer Lees-Marshment ◽  
Cliff van der Linden

Abstract. Research demonstrates that the negative relationship between Openness to Experience and conservatism is heightened among the informed. We extend this literature using national survey data (Study 1; N = 13,203) and data from students (Study 2; N = 311). As predicted, education – a correlate of political sophistication – strengthened the negative relationship between Openness and conservatism (Study 1). Study 2 employed a knowledge-based measure of political sophistication to show that the Openness × Political Sophistication interaction was restricted to the Openness aspect of Openness. These studies demonstrate that knowledge helps people align their ideology with their personality, but that the Openness × Political Sophistication interaction is specific to one aspect of Openness – nuances that are overlooked in the literature.


PsycCRITIQUES ◽  
2005 ◽  
Vol 50 (19) ◽  
Author(s):  
Michael Cole
Keyword(s):  
Top Down ◽  

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