The Lattice of Lambda Theories Lusin, Stefania; Salibra, Antonino
Journal of logic and computation,
06/2004, Letnik:
14, Številka:
3
Journal Article
Recenzirano
Odprti dostop
Lambda theories are equational extensions of the untyped lambda calculus that are closed under derivation. The set of lambda theories is naturally equipped with a structure of complete lattice, where ...the meet of a family of lambda theories is their intersection, and the join is the least lambda theory containing their union. In this paper we study the structure of the lattice of lambda theories by universal algebraic methods. We show that nontrivial quasi-identities in the language of lattices hold in the lattice of lambda theories, while every nontrivial lattice identity fails in the lattice of lambda theories if the language of lambda calculus is enriched by a suitable finite number of constants. We also show that there exists a sublattice of the lattice of lambda theories which satisfies: (i) a restricted form of distributivity, called meet semidistributivity; and (ii) a nontrivial identity in the language of lattices enriched by the relative product of binary relations.
The CDF plug upgrade electromagnetic calorimeter: test beam results Albrow, M.; Aota, S.; Apollinari, G. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
03/2002, Letnik:
480, Številka:
2
Journal Article
Recenzirano
Odprti dostop
The CDF Plug Upgrade calorimeter, which fully exploits the tile–fiber technique, was tested at the Fermilab meson beamline. The calorimeter was exposed to positron, positively charged pion and ...positive muon beams with energies in the range of 5–
230
GeV
. The energy resolution of the electromagnetic calorimeter to the positron beam is consistent with the design value of
16%/
E
⊕1%
, where E is the energy in units of GeV and ⊕ represents sum in quadrature. The non-linearity for positrons is studied in an energy range of 11–
181
GeV
. It is important to incorporate the response of the preshower detector, the first layer of the electromagnetic calorimeter which is readout separately, into that of the calorimeter to reduce the non-linearity to 1% or less. The energy scale is about
1.46
pC/
GeV
with HAMAMATSU R4125 operated typically at a gain of 2.5×10
4. The response non-uniformity over the surface of a tower of the electromagnetic calorimeter is found to be about 2% with
57
GeV
positrons. Studies of several detailed detector characteristics are also presented.
Plotkin has conjectured that there exists an absolutely unorderable combinatory algebra, namely a combinatory algebra which cannot be embedded in another combinatory algebra admitting a nontrivial ...compatible partial order. In this paper we prove that a wide class of combinatory algebras admits extensions with a nontrivial compatible partial order.
Aging tests of full-scale CMS muon cathode strip chambers Acosta, D.; Apollinari, G.; Arisaka, K. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
12/2003, Letnik:
515, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Two CMS production Cathode Strip Chambers were tested for aging effects in a high-radiation environment at the Gamma Irradiation Facility at CERN. The chambers were irradiated over a large area: in ...total, about 2.1
m
2 or 700
m of wire in each chamber. The 40% Ar+50% CO
2+10% CF
4 gas mixture was provided by an open-loop gas system for one of the chambers and by a closed-loop re-circulating gas system for the other. After an accumulation of 0.3–0.4
C/cm of a wire, equivalent to about 30–50 years of operation at peak LHC luminosity, no significant changes in gas gain, chamber efficiency and wire signal noise were observed for either of the two chambers. The only consistent signs of aging were a small increase in dark current from ∼2 to ∼10
nA per plane of 600 wires and a decrease of strip-to-strip resistance from 1000 to 10–100
GΩ. Disassembly of the chambers revealed deposits on the cathode planes, while the anode wires remained fairly clean.
Design features and test results of the CMS endcap muon chambers Acosta, D; Apollinari, G; Arisaka, K ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
11/2002, Letnik:
494, Številka:
1
Journal Article
Recenzirano
Presented are the main design features and performance results of the Cathode Strip Chambers for the CMS Endcap Muon system. Although the strips are unusually wide (up to
16
mm
) for the ...cathode-to-anode wire distance of
5
mm
, the six-plane structure of these chambers yields a spatial resolution of about
80
μm
, essentially uniform and independent of the strip width. In addition, the net spatial resolution of about one-tenth of the strip width at the hardware trigger level
(300
ns)
is obtained using a simple network of comparators. Time resolution achieved at the trigger level is
∼4
ns
(rms) that allows unambiguous tagging of bunch crossings which occur every
25
ns
. Aging test results, including those obtained with a recirculating gas system, are discussed; only minor aging affects were observed. The aging studies were performed with large-scale chambers;
700
m
of wire were irradiated for a dose up to
0.4
C/
cm
of the total accumulated charge.
Large CMS cathode strip chambers: design and performance Acosta, D; Apollinari, G; Blomquist, J ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
10/2000, Letnik:
453, Številka:
1
Journal Article
Recenzirano
Presented are the main design features of the large Cathode Strip Chambers (CSCs) for the CMS Endcap Muon System as well as the performance results obtained with the two full-scale 3.4×1.5 m
2 ...six-plane prototypes. The prototype performance was within the baseline requirements: (a) higher than 99% efficiency of muon track finding at the trigger level with more than 92% probability for bunch crossing identification and better than 2
mm spatial resolution, and (b) better than 150
μm spatial resolution in off-line.
We use intersection types as a tool for obtaining
λ-models. Relying on the notion of
easy intersection type theory, we successfully build a
λ-model in which the interpretation of an arbitrary simple ...easy term is any filter which can be described by a continuous predicate. This allows us to prove two results. The first gives a proof of consistency of the
λ-theory where the
λ-term (
λx.
xx)(
λx.
xx) is forced to behave as the join operator. This result has interesting consequences on the algebraic structure of the lattice of
λ-theories. The second result is that for any simple easy term, there is a
λ-model, where the interpretation of the term is the
minimal fixed point operator.
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