305,452 research outputs found
Distributed Processes, Distributed Cognizers and Collaborative Cognition
Cognition is thinking; it feels like something to think, and only those who can feel can think. There are also things that thinkers can do. We know neither how thinkers can think nor how they are able do what they can do. We are waiting for cognitive science to discover how. Cognitive science does this by testing hypotheses about what processes can generate what doing (“know-how”) This is called the Turing Test. It cannot test whether a process can generate feeling, hence thinking -- only whether it can generate doing. The processes that generate thinking and know-how are “distributed” within the heads of thinkers, but not across thinkers’ heads. Hence there is no such thing as distributed cognition, only collaborative cognition. Email and the Web have spawned a new form of collaborative cognition that draws upon individual brains’ real-time interactive potential in ways that were not possible in oral, written or print interactions
Distributed Processes, Distributed Cognizers and Collaborative Cognition
Cognition is thinking; it feels like something to think, and only those who can feel can think. There are also things that thinkers can do. We know neither how thinkers can think nor how they are able do what they can do. We are waiting for cognitive science to discover how. Cognitive science does this by testing hypotheses about what processes can generate what doing (“know-how”) This is called the Turing Test. It cannot test whether a process can generate feeling, hence thinking -- only whether it can generate doing. The processes that generate thinking and know-how are “distributed” within the heads of thinkers, but not across thinkers’ heads. Hence there is no such thing as distributed cognition, only collaborative cognition. Email and the Web have spawned a new form of collaborative cognition that draws upon individual brains’ real-time interactive potential in ways that were not possible in oral, written or print interactions
Inexact Convex Relaxations for AC Optimal Power Flow: Towards AC Feasibility
Convex relaxations of AC optimal power flow (AC-OPF) problems have attracted
significant interest as in several instances they provably yield the global
optimum to the original non-convex problem. If, however, the relaxation is
inexact, the obtained solution is not AC-feasible. The quality of the obtained
solution is essential for several practical applications of AC-OPF, but
detailed analyses are lacking in existing literature. This paper aims to cover
this gap. We provide an in-depth investigation of the solution characteristics
when convex relaxations are inexact, we assess the most promising AC
feasibility recovery methods for large-scale systems, and we propose two new
metrics that lead to a better understanding of the quality of the identified
solutions. We perform a comprehensive assessment on 96 different test cases,
ranging from 14 to 3120 buses, and we show the following: (i) Despite an
optimality gap of less than 1%, several test cases still exhibit substantial
distances to both AC feasibility and local optimality and the newly proposed
metrics characterize these deviations. (ii) Penalization methods fail to
recover an AC-feasible solution in 15 out of 45 cases, and using the proposed
metrics, we show that most failed test instances exhibit substantial distances
to both AC-feasibility and local optimality. For failed test instances with
small distances, we show how our proposed metrics inform a fine-tuning of
penalty weights to obtain AC-feasible solutions. (iii) The computational
benefits of warm-starting non-convex solvers have significant variation, but a
computational speedup exists in over 75% of the cases
On the "principle of the quantumness", the quantumness of Relativity, and the computational grand-unification
After reviewing recently suggested operational "principles of the
quantumness", I address the problem on whether Quantum Theory (QT) and Special
Relativity (SR) are unrelated theories, or instead, if the one implies the
other. I show how SR can be indeed derived from causality of QT, within the
computational paradigm "the universe is a huge quantum computer", reformulating
QFT as a Quantum-Computational Field Theory (QCFT). In QCFT SR emerges from the
fabric of the computational network, which also naturally embeds gauge
invariance. In this scheme even the quantization rule and the Planck constant
can in principle be derived as emergent from the underlying causal tapestry of
space-time. In this way QT remains the only theory operating the huge computer
of the universe. Is QCFT only a speculative tautology (theory as simulation of
reality), or does it have a scientific value? The answer will come from Occam's
razor, depending on the mathematical simplicity of QCFT. Here I will just start
scratching the surface of QCFT, analyzing simple field theories, including
Dirac's. The number of problems and unmotivated recipes that plague QFT
strongly motivates us to undertake the QCFT project, since QCFT makes all such
problems manifest, and forces a re-foundation of QFT.Comment: To be published on AIP Proceedings of Vaxjo conference. The ideas on
Quantum-Circuit Field Theory are more recent. V4 Largely improved, with new
interesting results and concepts. Dirac equation solve
Six Noise Type Military Sound Classifier
Blast noise from military installations often has a negative impact on the quality of life of residents living in nearby communities. This negatively impacts the military's testing \& training capabilities due to restrictions, curfews, or range closures enacted to address noise complaints. In order to more directly manage noise around military installations, accurate noise monitoring has become a necessity. Although most noise monitors are simple sound level meters, more recent ones are capable of discerning blasts from ambient noise with some success. Investigators at the University of Pittsburgh previously developed a more advanced noise classifier that can discern between wind, aircraft, and blast noise, while simultaneously lowering the measurement threshold. Recent work will be presented from the development of a more advanced classifier that identifies additional classes of noise such as machine gun fire, vehicles, and thunder. Additional signal metrics were explored given the increased complexity of the classifier. By broadening the types of noise the system can accurately classify and increasing the number of metrics, a new system was developed with increased blast noise accuracy, decreased number of missed events, and significantly fewer false positives
Performance Testing and Analysis of Synchronous Reluctance Motor Utilizing Dual-phase Magnetic Material
While interior permanent magnet (1PM) machines have been considered the state-of-the art for traction motors, synchronous reluctance (SynRel) motors with advanced materials can provide a competitive alternative. 1PM machines typically utilize Neodymium 1ron Boron (NdFeB) permanent magnets, which pose an issue in terms of price, sustainability, demagnetization at higher operating temperatures, and uncontrolled generation. On the other hand, SynRel machines do not contain any magnets and are free from these issues. However, the absence of magnets as well the presence of bridges and centerposts limit the flux-weakening capability of a SynRel machine and limit the achievable constant power speed ratio (CPSR) without having to significantly oversize the machine and/or the power converter. 1n this paper, a new material referred to as the dual-phase magnetic material where nonmagnetic regions can be selectively introduced within each lamination will be evaluated for SynRel designs. The dual-phase feature of this material enables non-magnetic bridges and posts, eliminating one of the key limitations of the SynRel designs in terms of torque density and flux-weakening. This paper will present, the design, analysis and test results of an advanced proof-of-concept SynRel design utilizing dual-phase material with traction applications as the ultimate target application
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Development of a Standard Testing Method for Vehicle Cabin Air Quality Index
Direct Flux Field Oriented Control of IPM Drives with Variable DC-Link in the Field-Weakening Region
This paper presents the direct flux control of an interior permanent-magnet (IPM) motor drive in the field-weakening region. The output torque is regulated by the coordinated control of the stator flux amplitude and the current component in quadrature with the flux, and it is implemented in the stator flux reference frame. The control system guarantees maximum torque production taking into account voltage and current limits, in particular in case of large dc-link variations. The field-oriented control does not necessarily require an accurate magnetic model of the IPM motor, and it is able to exploit the full inverter voltage at different dc-link levels with no additional voltage control loop. The feasibility of the proposed control method is investigated in discrete-time simulation, then tested on a laboratory rig, and finally implemented on board of an electric scooter prototype. The motor under test is an IPM permanent-magnet-assisted synchronous reluctance machine, with high-saliency and limited permanent-magnet flu
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