910 research outputs found
A Note on Carnap’s Result and the Connectives
Carnap’s result about classical proof-theories not ruling out non-normal
valuations of propositional logic formulae has seen renewed philosophical
interest in recent years. In this note I contribute some considerations which
may be helpful in its philosophical assessment. I suggest a vantage point
from which to see the way in which classical proof-theories do, at least to a
considerable extent, encode the meanings of the connectives (not by
determining a range of admissible valuations, but in their own way), and I
demonstrate a kind of converse to Carnap’s result
The accident of logical constants
Work on the nature and scope of formal logic has focused unduly on the distinction between logical and extra-logical vocabulary; which argument forms a logical theory countenances depends not only on its stock of logical terms, but also on its range of grammatical categories and modes of composition. Furthermore, there is a sense in which logical terms are unnecessary. Alexandra Zinke has recently pointed out that propositional logic can be done without logical terms. By defining a logical-term-free language with the full expressive power of first-order logic with identity, I show that this is true of logic more generally. Furthermore, having, in a logical theory, non-trivial valid forms that do not involve logical terms is not merely a technical possibility. As the case of adverbs shows, issues about the range of argument forms logic should countenance can quite naturally arise in such a way that they do not turn on whether we countenance certain terms as logical
Design of the 12-bit Delta-Sigma Modulator using SC Technique for Vibration Sensor Output Processing
The work deals with the design of the 12-bit Delta-Sigma modulator using switched capacitors (SC) technique. The modulator serves to vibration sensor output processing. The first part describes the Delta-Sigma modulator parameters definition. Results of the proposed topology ideal model were presented as well. Next, the Delta-Sigma modulator circuitry on the transistor level was done. The ONSemiconductor I2T100 0.7 um CMOS technology was used for design. Then, the Delta-Sigma modulator nonidealities were simulated and implemented into the MATLAB ideal model of the modulator. The model of real Delta-Sigma modulator was derived. Consequently, modulator coefficients were optimized. Finally, the corner analysis of the Delta-Sigma modulator with the optimized coefficients was simulated. The value of SNDR = 82.2 dB (ENOB = 13.4 bits) was achieved
Against the Brogaard-Salerno Stricture
'It is widely agreed that contraposition, strengthening the antecedent and hypothetical syllogism fail for subjunctive conditionals', write Brogaard and Salerno in (2008: Counterfactuals and context, Analysis 68.1, 39–46). In that article they argue that the putative counterexamples to these principles are actually no threat, on the grounds that they involve a certain kind of illicit contextual shift. -/- Here I argue that this particular kind of contextual shift, if it is properly so called, is not generally illicit, and that therefore the counterexamples shouldn't be blocked with the kind of blanket restriction Brogaard and Salerno advocate. The idea that the reasoning patterns in question can be vindicated given restrictions still seems promising; the purpose of this note is to show that the simple restriction proposed by Brogaard and Salerno isn't the right way of going
A Problem for Hofweber’s Ontological Project
Thomas Hofweber's well-known ontological project crucially involves inferring negative existential statements from statements of non-reference, i.e. statements that say that some term or terms do not refer. Here, after explaining the context of this move, I aim to show that it is fallacious, and that this vitiates Hofweber's ontological project
Quantum gate using qubit states separated by terahertz
A two-qubit quantum gate is realized using electronic excited states in a
single ion with an energy separation on the order of a terahertz times the
Planck constant as a qubit. Two phase locked lasers are used to excite a
stimulated Raman transition between two metastable states and
separated by 1.82 THz in a single trapped Ca ion to
construct a qubit, which is used as the target bit for the Cirac-Zoller
two-qubit controlled NOT gate. Quantum dynamics conditioned on a motional qubit
is clearly observed as a fringe reversal in Ramsey interferometry.Comment: 4 pages, 4 figure
Generation of a decoherence-free entangled state using a radio frequency dressed state
We propose the generation of entangled states with trapped calcium ions using
a combination of an rf dressed state and a spin dependent force. Using this
method, a decoherence-free entangled state of rf qubits can be directly
generated and ideally its fidelity is close to unity. We demonstrate an rf
entangled state with a fidelity of 0.68, which has a coherence time of more
than 200 ms by virtue of the fact that it is an eigenstate with energy gaps
between adjacent levels.Using the same technique, we also produce a
qutrit-qutrit entangled state with a fidelity of 0.77, which exceeds the
threshold value for separability of 2/3.Comment: 4 figure
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