Two-variable descriptions of regularity

Summary form only given. We present the reflectance spectra of conducting polyaniline film protonated with sulfuric acid (PANI-H/sub 2/SO/sub 4/) and of newly processed film protonated with camphor sulfonic acid (PANI-CSA) over a wide spectral range (0.006 eV-6 eV) at room temperature. The reflectance of PANI-H/sub 2/SO/sub 4/reveals the signatures of the intraband excitations in the infrared (IR), including increasing reflectance approaching to far-IR and a reflectance minimum around 1.7 eV. However, the corresponding optical conductivity (/spl sigma/(/spl omega/)) and the real part of dielectric function (/spl epsiv//sub 1/(/spl omega/)) are far from those of a metal. Instead, the optical spectra indicate that the charge carriers are localized with considerable oscillator strength within the gap. On the other hand, the optical spectra of PANI- CSA are characterized by distinct metal-like signatures arising from the combination of the Drude-like free carrier excitations in the far-IR and the existence of plasma resonance around 1.2 eV. These results indicate that the new processing of polyaniline with functionalized sulfonic acid (with surfactants as counterions) has greatly improved the homogeneity of the material and has resulted in a significant decrease in the extent of molecular scale disorder, thereby leading to the delocalization of the charge carriers in PANI-CSA. However, the deviation of /spl sigma/(/spl omega/) and /spl epsiv//sub 1/(/spl omega/) from the normal Drude metallic behaviors below 0.2 eV indicates that disorder induced localization still plays an important role in PANI-CSA. We present a quantitative analysis of /spl sigma/(/spl omega/) and /spl spl epsiv//sub 1/(/spl omega/) of PANI-CSA in terms of the localization modified Drude model, implying that PANI-CSA is a disordered metal on the metal-insulator boundary.

The spectroscopic properties of Ho/sup 3+/ laser channels in KGd(WO/sub 4/)/sub 2/ crystals have been investigated using optical absorption, photoluminescence, and lifetime measurements. The radiative lifetimes of Ho/sup 3+/ have been calculated through a Judd-Ofelt (JO) formalism using 300-K optical absorption results. The JO parameters obtained were /spl Omega//sub 2/=15.35/spl times/10/sup -20/ cm/sup 2/, /spl Omega//sub 4/=3.79/spl times/10/sup -20/ cm/sup 2/, /spl Omega//sub 6/=1.69/spl times/10/sup -20/ cm/sup 2/. The 7-300-K lifetimes obtained in diluted (8/spl middot/10/sup 18/ cm/sup -3/) KGW:0.1% Ho samples are: /spl tau/(/sup 5/F/sub 3/)/spl ap/0.9 /spl mu/s, /spl tau/(/sup 5/S/sub 2/)=19-3.6 /spl mu/s, and /spl tau/(/sup 5/F/sub 5/)/spl ap/1.1 /spl mu/s. For Ho concentrations below 1.5/spl times/10/sup 20/ cm/sup -3/, multiphonon emission is the main source of non radiative losses, and the temperature independent multiphonon probability in KGW is found to follow the energy gap law /spl tau//sub ph//sup -1/(0)=/spl beta/exp(-/spl alpha//spl Delta/E), where /spl beta/=1.4/spl times/10/sup -7/ s/sup -1/, and /spl alpha/=1.4/spl times/10/sup 3/ cm. Above this holmium concentration, energy transfer between Ho impurities also contributes to the losses. The spectral distributions of the Ho/sup 3+/ emission cross section /spl sigma//sub EM/ for several laser channels are calculated in /spl sigma/- and /spl pi/-polarized configurations. The peak a /spl sigma//sub EM/ values achieved for transitions to the /sup 5/I/sub 8/ level are /spl ap/2/spl times/10/sup -20/ cm/sup 2/ in the /spl sigma/-polarized configuration, and three main lasing peaks at 2.02, 2.05, and 2.07 /spl mu/m are envisaged inside the /sup 5/I/sub 7//spl rarr//sup 5/I/sub 8/ channel.

A finite-difference time-domain (FDTD) analysis is presented to simulate, up to the high-frequency regime, transients on multiconductor transmission lines above dissipative earth. Excitation is in the high-frequency regime if the pulse has significant spectral content up to /spl omega//spl ap//spl omega//sub c/, with /spl omega//sub c/ the frequency where the conduction and displacement current densities have equal magnitude. Thus, /spl omega//sub c/=/spl sigma//sub g///spl epsi//sub 0//spl epsi//sub rg/ with /spl sigma//sub g/ and /spl epsi//sub rg/ the ground conductance and relative permittivity. The FDTD algorithm extends the formulation of Agrawal et al. (1980), by incorporating the theory of D'Amore and Sarto for the interaction of wide-band transients with the earth. Careful experimental testing of the new algorithm is presented. The measurement configuration consists of two parallel wires; first suspended above an aluminum sheet to test the code in the low-frequency regime; then above a block of absorbing material for experiments in the high-frequency regime. The end of one of the conductors is driven with a 2-ns synthesized impulse by a stepped-frequency, automatic network analyzer. Reflected and cross-talk signals are presented in the time domain. These show good agreement with the numerically predicted common mode, differential mode and mode-converted pulses.

There has been significant research effort focussed on the study of regular languages, since they play a vital role in our understanding of computation. This existing research draws a large number of connections with other areas, such as algebra and symbolic logic. Recently, research has begun into how diagrammatic logics can define regular languages, providing another mechanism through which we can understand regular languages. However, the formalised diagrammatic logics are first-order, so they cannot define non-starfree regular languages. The primary contributions of this paper are: (a) to develop and formalise a second-order diagrammatic logic, extending spider diagrams of order, and (b) to establish a class of regular languages that this logic can define. This lays the essential foundations for providing an exact classification of the regular languages that are definable using this new second-order logic.

In this article we investigate the family of independence-friendly (IF) logics in the equality-free setting, concentrating on questions related to expressive power. Various natural equality-free fragments of logics in this family translate into existential second-order logic with prenex quantification of function symbols only and with the first-order parts of formulae equality-free. We study this fragment of existential second-order logic. Our principal technical result is that over finite models with a vocabulary consisting of unary relation symbols only, this fragment of second-order logic is weaker in expressive power than first-order logic (with equality). Results about the fragment could turn out useful for example in the study of independence-friendly modal logics. In addition to proving results of a technical nature, we address issues related to a perspective from which IF logic is regarded as a specification framework for games, and also discuss the general significance of understanding fragments of second-order logic in investigations related to non-classical logics.

In a discussion of high-field conductivity in solid dielectrics, the author inquires as to whether the limiting field is a strong function of the high field conduction model chosen and the model chosen causes substantial variations of other important parameters such as the power density in the high field region. The analysis is based on the AC conduction data of T. M. Tokoro et al. (1992), measured as a function of electric field and temperature. It is suggested that, if a defect-tolerant dielectric could be developed, it would be thermally stable for reasonable defects and power frequency application. Power dissipation and temperature rise do not appear to be strong functions of the model for /spl sigma/(E) when /spl sigma/(E)=/spl omega//spl epsi/ at the same fixed value of E. As a result, a defect-tolerant dielectric appears to be theoretically feasible.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

CdS layers obtained by chemical bath deposition (CBD) are usually used as buffer layer in chalcogenide based thin film solar cells. However, if good results are obtained, cadmium is toxic for the environment while the break of the physical vapour deposition (PVD) cycle, needed for CBD-CdS, constitutes a bottleneck in the process. Therefore many attempts are under way, all over the world, to obtain Cd free buffer layers. In the present work CuAlX/sub 2/ (X = Se, Te) and In/sub 2/S/sub 3/ have been obtained by vacuum deposition and annealing treatment. Their properties are compared to those of CdS buffer layer. The CuAlX/sub 2/ (X = Se, Te) and In/sub 2/S/sub 3/ films are crystallized in the chalcopyrite and the cubic structure respectively. The measured band gaps are 2.4 eV, 2.7 eV and 2.9 eV for CuAlTe/sub 2/, CuAlSe/sub 2/ and In/sub 2/S/sub 3/ respectively. While In/sub 2/S/sub 3/ is systematically n-type, a Zn treatment allows n-type films of CuAlX/sub 2/ to be obtained. The films are resistive (10/sup -6/ /spl Omega//sup -1/cm/sup -1/ < /spl sigma/ < 10/sup -3/ /spl Omega//sup -1/ cm/sup -1/). All these properties made CuAlX/sub 2/ (X = Se, Te) and In/sub 2/S/sub 3/ good candidates as new buffer layers. A first attempt, using Mo/CuInSe/sub 2//In/sub 2/S/sub 3//ZnO cell, has been performed; the efficiency obtained is 8 %.

This paper reveals the relationship between eigenvector and robust pole clustering in general subregions of the complex plane for uncertain matrices. It presents a set of new necessary and sufficient conditions for robust pole clustering in general regions for uncertain matrices via their eigenvector directions. The eigenvector directions are viewed and measured in a fixed basis in the vector space. The basis is constituted by the orthonormal eigenvectors of symmetric matrix, called a criterion f(A, A*)=/spl Sigma//sub p,q/c/sub pq/A*/sup q/A/sup p/, related to the nominal matrix. It will not be changed when uncertain matrix parameters change because it is related only to the nominal matrix. The considered robust pole clustering regions include /spl Omega/-transformable regions and non-/spl Omega/-transformable regions. The concerned uncertainties include both structured and unstructured uncertainties. The results may be applied to control systems for robust pole clustering analysis and design. The interesting thing is that the robust stability and robust performance, i.e., robust pole clustering, are represented and achieved via their eigenvector directions.

We prove that for any decision tree calculating a Boolean function f : {-1,1}/sup n/ /spl rarr/ {-1, 1}, Var[f] /spl les/ /spl Sigma/ /sub i=1/ /sup n/ /spl delta//sup i/Inf/sub i/(f), i = 1 where /spl delta//sup i/ is the probability that the ith input variable is read and Inf/sub i/(f) is the influence of the ith variable on f. The variance, influence and probability are taken with respect to an arbitrary product measure on {-1, 1}/sup n/n. It follows that the minimum depth of a decision tree calculating a given balanced function is at least the reciprocal of the largest influence of any input variable. Likewise, any balanced Boolean function with a decision tree of depth d has a variable with influence at least 1/d. The only previous nontrivial lower bound known was /spl Omega/(d2/sup -d/). Our inequality has many generalizations, allowing us to prove influence lower bounds for randomized decision trees, decision trees on arbitrary product probability spaces, and decision trees with nonBoolean outputs. As an application of our results we give a very easy proof that the randomized query complexity of nontrivial monotone graph properties is at least/spl Omega/(v/sup 4/3//p/sup 1/3/), where v is the number of vertices and p /spl les/ 1/2 is the critical threshold probability. This supersedes the milestone /spl Omega/(v/sup 4/3//p/sup 1/3/) bound of Hajnal (1991) and is sometimes superior to the best known lower bounds of Chakrabarti-Khot (2001) and Friedgut-Kahn-Wigderson (2002).

Existential second-order logic and modal logic with quantified accessibility relations

The DISTO collaboration has built a large-acceptance magnetic spectrometer designed to provide broad kinematic coverage of multi-particle final states produced in $pp$ scattering. The spectrometer has been installed in the polarized proton beam of the Saturne accelerator in Saclay to study polarization observables in the $\\vec{p} p \\to p K^{+} \\vec{Y}$ ($Y = \\Lambda, \\Sigma^{0}$ or $Y^{*}$) reaction and vector meson production ($\\phi, \\omega$ and $\\rho$) in $pp$ collisions. The data acquisition system is based on a VME 68030 CPU running the OS/9 operating system, housed in a single VME crate together with the CAMAC interface, the triple port ECL memories, and four RISC R3000 CPU. The digitization of signals from the detectors is made by PCOS III and FERA front-end electronics. Data of several events belonging to a single Saturne extraction are stored in VME triple-port ECL memories using a hardwired fast sequencer. The buffer, optionally filtered by the RISC R3000 CPU, is recorded on a DLT cassette by DAQ CPU using the on-board SCSI interface during the acceleration cycle. Two UNIX workstations are connected to the VME CPUs through a fast parallel bus and the Local Area Network. They analyze a subset of events for on-line monitoring. The data acquisition system is able to read and record 3500 ev/burst in the present configuration with a dead time of 15%.

The present paper discusses the interfacial structure and the effect on the magnetic and magneto-optical properties in TbFeCo/Pt multilayer films, in contrast with Fe/Pt multilayers. Both the magnetic and magneto-optical properties are explained well when an interfacial region very similar to an Fe-Pt alloy is assumed. Low angle X-ray diffraction analyses reveal that the Fe-Pt alloy-like interfacial regions are formed mainly on top of TbFeCo layers, but little on Pt layers, /spl omega//spl sigma//sub xy/ spectra indicate that polarization of Pt in the interfacial region is different from that in Fe/Pt multilayers.

We present, for the first time, dramatic improvements in the titanium silicide quality by adding SiF/sub 3//sup +/ mixing implantation in advanced CMOS SALICIDE (Self-aligned silicide) process. We obtained 4/spl times/ reduction in contact resistance and an extremely tight distribution (/spl sigma/-0.09 /spl Omega/) for N+, P+, N-poly, and P-poly contacts. Due to the introduction of fluorine in this process, we observed that the Gm degradation after 500 s constant voltage stressing is improved by 12/spl times/ for SiF/sub 3//sup +/ implanted silicided MOSFET. The silicides with SiF/sub 3//sup +/ mixing implantation have very unique properties compared with other mixing implantation using atomic species alone. This technique will improve the circuit performance, reliability, and yield in advanced CMOS process.

It is shown that the impulsive (generalized) systems can be combined with usual bang-bang disturbance systems to yield mixed disturbance action systems. The state response is governed by nonlinear differential equations with bounded disturbance action /spl omega/ and impulse disturbance action /spl upsi/. The impulse disturbance action has its structure given that is affine /spl upsi/=/spl Sigma//sub i=1//sup k/ c/sub i//spl delta/(t-t/sub i/), |c/sub i/|/spl les/1. In this case the differential equation solution is a discontinuous function. After changing the original task into k+1 auxiliary combined degrading severity tasks, we get the necessary conditions for the most stressful disturbance of mixed action for some stable systems. Examples are given to illustrate the theory.

We first experimentally observed the doubly-excited electronic state 2/sup 1//spl Delta//sub g/ of Na/sub 2/ dissociating into Na (3p) + Na (3p) limit. This state has the deepest interaction potential well among the 12 electronic states formed from this first doubly-excited limit. A single line Ar/sup +/ laser (total of 4 lines) was used to excite the Na/sub 2/ molecules from ground state X/sup 1//spl Sigma//sub g//sup +/ to the intermediate B/sup 1//spl Pi//sub u/ state. A solid-state pumped single mode Ti:sapphire laser was scanning from 12100 to 14300 cm/sup -1/ to search oh the optical-optical double resonance (OODR) signals. Using a combination of filters and photomultiplier tube to detect the total fluorescence from the OODR, more than 150 ro-vibrational levels from the 2/sup 1//spl Delta//sub g/ state were observed. Comparing the detected excitation intensity with the Franck-Condon factors and the observed vibrational separations with theoretical calculations, the lowest observed vibrational quantum number were assigned to /spl nu/ = 3. The T/sub e/, /spl omega//sub e/, and B/sub e/ from Dunham expansion fitting are 32540.669 cm/sup -1/, 124.039 cm/sup -1/ and 0.1186 cm-1, respectively.