cssi/SciSciGPT-SciSciNet huggingface dataset:
The Physical Principles of Magneto-optical Recording

From the Publisher: This book covers the physics of magneto-optical recording, beginning with first principles and working through to contemporary state-of-the-art topics. Both optics and magnetism are broad subjects, each with many applications in modern technology. This book prepares the reader for advanced work in either field. The first half of the book teaches the theory of diffraction using an original unified approach. It also covers the optics of multilayers (including dielectric, metal, birefringent and magnetic layers), polarization optics, noise in photodetection, and thermal aspects. The second half of the book describes the basics of magnetism and magnetic materials, magneto-static field calculations, domains and domain walls, the mean-field theory of magnetism, magnetization dynamics, the theory of coercivity, and the process of thermomagnetic recording. In each chapter, throughout the book, after coverage of the fundamentals the author explains the relevance of the topic to magneto-optical recording, and examples are given that emphasize this particular connection. Numerous examples based on real-world problems encountered in the engineering design of magneto-optical media and systems will give the reader valuable insights into the science and technology of optical recording. In addition, there are extensive problem sets at the ends of the chapters. This book may be used as an advanced textbook on optical recording in both physics and engineering departments, and also as a reference work for scientists and engineers in industrial and academic laboratories.
On Kostant's partial order on hyperbolic elements

We study Kostant's partial order on the elements of a semisimple Lie group in relations with the finite-dimensional representations. In particular, we prove the converse statement of Theorem 6.1 given by Kostant [B. Kostant, On convexity, the Weyl group and the Iwasawa decomposition, Ann. Sci. Ecole Norm. Sup. 6 (1973), pp. 413–455] on hyperbolic elements.
Personality and physical activity: A systematic review and meta-analysis.

Abstract Whether personality determines physical activity or its outcomes is relevant for theory and public health but has been understudied. We estimated the population correlations between Big-Five personality factors and physical activity and examined whether they varied according to sample characteristics and study features. Database searches were conducted according to PRISMA guidelines, for articles published in the English language prior to November 1st, 2013. Sixty-four studies including a total of 88,400 participants yielded effects (k) for Extraversion (88), Neuroticism (82), Conscientiousness (69), Openness (51) and Agreeableness (52). Significant mean r was found for Extraversion (r = .1076), Neuroticism (r = −.0710), Conscientiousness (r = .1037) and Openness (r = .0344), but not Agreeableness (r = .0020). Effects were moderately heterogeneous (I2 range = 44–65%) and varied by sample characteristics (e.g., age, gender, or clinical status) and/or study features (e.g., measure quality or item format). This analysis expands results of previous reviews and provides new support for a relationship between physical activity and Openness. Future studies should use better measures of physical activity and prospective designs, adjust for statistical artifacts, and consider advances in the conceptualization of personality.
Modulation Depth Estimation and Variable Selection in State-Space Models for Neural Interfaces

Rapid developments in neural interface technology are making it possible to record increasingly large signal sets of neural activity. Various factors such as asymmetrical information distribution and across-channel redundancy may, however, limit the benefit of high-dimensional signal sets, and the increased computational complexity may not yield corresponding improvement in system performance. High-dimensional system models may also lead to overfitting and lack of generalizability. To address these issues, we present a generalized modulation depth measure using the state-space framework that quantifies the tuning of a neural signal channel to relevant behavioral covariates. For a dynamical system, we develop computationally efficient procedures for estimating modulation depth from multivariate data. We show that this measure can be used to rank neural signals and select an optimal channel subset for inclusion in the neural decoding algorithm. We present a scheme for choosing the optimal subset based on model order selection criteria. We apply this method to neuronal ensemble spike-rate decoding in neural interfaces, using our framework to relate motor cortical activity with intended movement kinematics. With offline analysis of intracortical motor imagery data obtained from individuals with tetraplegia using the BrainGate neural interface, we demonstrate that our variable selection scheme is useful for identifying and ranking the most information-rich neural signals. We demonstrate that our approach offers several orders of magnitude lower complexity but virtually identical decoding performance compared to greedy search and other selection schemes. Our statistical analysis shows that the modulation depth of human motor cortical single-unit signals is well characterized by the generalized Pareto distribution. Our variable selection scheme has wide applicability in problems involving multisensor signal modeling and estimation in biomedical engineering systems.
Structural revision of glabramycins B and C, antibiotics from the fungus Neosartorya glabra by DFT calculations of NMR chemical shifts and coupling constants

Glabramycins B and C are antibacterial natural products produced by the fungal organism Neosartorya glabra. Their stereochemical structures have not been completely defined to date. In this work, DFT calculations are employed to predict the expected carbon-13 NMR chemical shifts and key vicinal proton–proton coupling constants for all of the candidate stereoisomers. By comparison with experimentally measured values, the complete relative stereochemical configurations for glabramycins B and C are established.
Fusion rings for degenerate minimal models

We study fusion rings for degenerate minimal models (p=q case) for N=0 and N=1 (super)conformal algebras. We consider a distinguished family of modules at the level c=1 and c=3/2 and show that the corresponding fusion rings are isomorphic to the representation rings for sl(2,C) and osp(1|2), respectively.
Light-Induced Temperature Jump Causes Power-Dependent Ultrafast Kinetics of Electrons Generated in Multiphoton Ionization of Liquid Water†

Picosecond geminate recombination kinetics for electrons generated by multiphoton ionization of liquid water become power dependent when the irradiance of the excitation light is greater than 0.3−0.5 TW/cm2 (the terawatt regime). To elucidate the mechanism of this power dependence, tri- 400 nm photon ionization of water has been studied using pump−probe laser spectroscopy on the pico- and femtosecond time scales. We suggest that the observed kinetic transformations are caused by a rapid temperature jump in the sample. Such a jump is inherent to multiphoton ionization in the terawatt regime, when the absorption of the pump light along the optical path becomes very nonuniform. The heating of water is substantial (tens of °C) because the 3-photon quantum yield of the ionization is relatively low, ca. 0.42, and a large fraction of the excitation energy is released into the solvent bulk as heat. Evidence of the temperature jump is the observation of a red shift in the absorption spectrum of (thermalized) elect...
Peer‐Based Approach for Analytical Procedures

This study extends the existing research in analytical procedures by allowing for learning from contemporaneous information transfers among peer companies. We introduce an approach for selecting peers for each client and perform tests to examine the contribution of peers' information to the performance of analytical procedures. We find that peer data are imperfect substitutions for contemporaneous firmspecific variables when such variables are not in error. However, we observe that contemporaneous peer specific data are especially beneficial when coordinated errors exist in multiple accounts. We demonstrate that when errors are seeded into two contemporaneous accounts, peer models perform better at detecting errors. We also find that fast‐changing companies experience inferior prediction and error detection accuracy, and that larger companies experience more accurate prediction, lower Type II errors, and higher Type I errors. Additionally, we observe that significant improvements in the performance of ana...
Neutral Nazarov-Type Cyclization Catalyzed by Palladium(0)

The first Pd(0)-catalyzed Nazarov-type cyclization of diketoesters proceeds in 70% to 95% yield under strictly neutral conditions. Aryl substitution is not required so the reaction succeeds with aliphatic substrates. The mechanism appears to be novel. A single asymmetric version of this reaction is also reported.
Genome-Wide Significance Levels and Weighted Hypothesis Testing

Genetic investigations often involve the testing of vast numbers of related hypotheses simultaneously. To control the overall error rate, a substantial penalty is required, making it difficult to detect signals of moderate strength. To improve the power in this setting, a number of authors have considered using weighted p-values, with the motivation often based upon the scientific plausibility of the hypotheses. We review this literature, derive optimal weights and show that the power is remarkably robust to misspecification of these weights. We consider two methods for choosing weights in practice. The first, external weighting, is based on prior information. The second, estimated weighting, uses the data to choose weights.
Enriched P-partitions and peak algebras

Abstract We develop a more general view of Stembridge's enriched P -partitions and use this theory to outline the structure of peak algebras for the symmetric group and the hyperoctahedral group. Initially we focus on commutative peak algebras, spanned by sums of permutations with the same number of peaks, where we consider several variations on the definition of “peak.” Whereas Stembridge's enriched P -partitions are related to quasisymmetric functions (the dual coalgebra of Solomon's type A descent algebra), our generalized enriched P -partitions are related to type B quasisymmetric functions (the dual coalgebra of Solomon's type B descent algebra). Using these functions, we move on to explore (non-commutative) peak algebras spanned by sums of permutations with the same set of peaks. While some of these algebras have been studied before, our approach gives explicit structure constants with a combinatorial description.
Development of Magnetohydrodynamic Flow in a Parallel-Plate Channel in an Inclined Field

A study has been made on the steady, incompressible developing MHD flow in a parallel-plate channel. The applied magnetic field is uniform but its direction makes an arbitrary angle with the channel axis. The full Navier-Stokes equations have been employed in the analysis. Velocity development and induced magnetic fields are found. The results show that for a weak field the entrance length decreases with the magnetic field and only the transverse component of the field has an effect. However, in a strong field the entrance length is found to either increase or decrease with the field depending upon the angle of inclination.
The Average Star Formation Histories of Galaxies in Dark Matter Halos from z = 0-8

We present a robust method to constrain average galaxy star formation rates (SFRs), star formation histories (SFHs), and the intracluster light (ICL) as a function of halo mass. Our results are consistent with observed galaxy stellar mass functions, specific star formation rates (SSFRs), and cosmic star formation rates (CSFRs) from z = 0 to z = 8. We consider the effects of a wide range of uncertainties on our results, including those affecting stellar masses, SFRs, and the halo mass function at the heart of our analysis. As they are relevant to our method, we also present new calibrations of the dark matter halo mass function, halo mass accretion histories, and halo-subhalo merger rates out to z = 8. We also provide new compilations of CSFRs and SSFRs; more recent measurements are now consistent with the buildup of the cosmic stellar mass density at all redshifts. Implications of our work include: halos near 1012 M ☉ are the most efficient at forming stars at all redshifts, the baryon conversion efficiency of massive halos drops markedly after z ~ 2.5 (consistent with theories of cold-mode accretion), the ICL for massive galaxies is expected to be significant out to at least z ~ 1-1.5, and dwarf galaxies at low redshifts have higher stellar mass to halo mass ratios than previous expectations and form later than in most theoretical models. Finally, we provide new fitting formulae for SFHs that are more accurate than the standard declining tau model. Our approach places a wide variety of observations relating to the SFH of galaxies into a self-consistent framework based on the modern understanding of structure formation in ΛCDM. Constraints on the stellar mass-halo mass relationship and SFRs are available for download online.
Topological defects, surface geometry and cohesive energy of twisted filament bundles

Cohesive assemblies of filaments are a common structural motif found in diverse contexts, ranging from biological materials such as fibrous proteins, to artificial materials such as carbon nanotube ropes and micropatterned filament arrays. In this paper, we analyze the complex dependence of cohesive energy on twist, a key structural parameter of both self-assembled and fabricated filament bundles. Based on the analysis of simulated ground states of cohesive bundles, we show that the non-linear influence of twist derives from two distinct geometric features of twisted bundles: (i) the geometrical frustration of inter-filament packing in the bundle cross-section; and (ii) the evolution of the surface geometry of bundles with twist, which dictates the cohesive cost of non-contacting filaments at the surface. Packing frustration in the bundle core gives rise to the appearance of a universal sequence of topological defects, excess 5-fold disclinations, with increasing twist, while the evolution of filament contact at the surface of the bundle generically favors twisted geometries for sufficiently long filaments. Our analysis of both continuum and discrete models of filament bundles shows that, even in the absence of external torque or intrinsic chirality, cohesive energy universally favors twisted ground states above a critical (length/radius) aspect ratio and below a critical filament stiffness threshold.
Introduction: quantitative histochemistry.

A PANEL on histochemical technologies, applicable to neurochemical pathology, is especially germane at this Conference because of the complex microscopic anatomy of the central nervous system and the consequent compelling need for analytical methods capable of establishing correlations between chemical composition and histological structure. Three major principles and congruent technical measures have been employed for this purpose :l (1) Qualitative histo- and cytochemistry enabling in situ identification of biochemical constituents in light and electron microscopic preparations. This classical form of histochemistry is elaborated and exemplified by other panelists. (2) Use of differential gradient density techniques for preparation (with subsequent macro analysis) of subcellular cytological constituents (nuclei, mitochrondia, synaptosomes etc.) and of enriched fractions of neurons, astrocytes, oligodendrocytes, myelin sheaths and axons. With respect to the nervous system, important contributions in these spheres have been those of V. Whitaker (U.K.), E. de Robertis (Argentina), S. Rose (U.K.) and W. Norton (U.S.A.) (3) Quantitative histochemistry based on the preparation of microgram or sub-microgram sized tissue samples of known histological composition on which direct analyses for chemical structural components or enzyme activities can be carried out using miniaturized forms of standard biochemistry. Procedures of this sort were developed originally by LinderstromLang and Holter in the Carlsberg Laboratories, Copenhagen.2 Remarkable extensions and refinements of such techniques to levels permitting single cell analysis we owe especialiy to Lowry3 and HydCn4. Our laboratory has been concerned for many years with applying microgram level quantitative histochemical techniques, applicable to samples of histological dimensions, to the normal and diseased nervous system. Within this context a central program has been the one dealing with the microchemical anatomy and pathology of mammalian cerebral cortex referred to in my earlier presentation at this Conference. Its objectives have been to analyze cortical biochemical fine structure in terms of its microscopic anatomy, and to search for chemoarchitectonic alterations in disease. The results also permit inferential correlations between biochemical composition and histological structure, normal and otherwise. The experimental design serving these objectives has consisted in preparing from fresh,
Parameterized maximum path coloring

We study the well-known Max Path Coloring problem from a parameterized point of view, focusing on trees and low-treewidth networks. We observe the existence of a variety of reasonable parameters for the problem, such as the maximum degree and treewidth of the network graph, the number of available colors and the number of requests one seeks to satisfy or reject. In an effort to understand the impact of each of these parameters on the problem's complexity we study various parameterized versions of the problem deriving fixed-parameter tractability and hardness results both for undirected and bi-directed graphs.
Solvent dynamical effects in electron transfer: molecular dynamics simulations of reactions in methanol

Abstract Molecular-dynamics simulations of solvation dynamics accompanying activated electron-transfer (ET) reactions in methanol have been undertaken in order to explore the physical nature of the solvent dynamics coupled to ET barrier crossing, and to probe some underlying reasons for the facile kinetics observed in this solvent. The reactant is modeled by a pair of Lennard-Jones (LJ) spheres in contact, of varying diameter (4 or 5 A), and containing a univalent charge (cation or anion) on one site so to probe possible effects of the ionic charge sign. Following equilibration, the collective solvent response to a sudden charge transfer between the spherical sites is followed, and described in terms of the response function C(t), describing the difference in the solvent-induced electrostatic potential between the initial and final solute states. In all cases, the C(t) curves exhibit a very rapid (50–100 fs) initial decay component associated with hydroxyl inertial motion, followed by components arising from hydrogen-bond librational and diffusive motions. Interestingly, the dynamics and relative importance of these relaxation modes are dependent on the charge sign as well as size of the solute pair. The molecular-level origins of these sensitivities are explored by examining time-dependent radial distribution functions, which implicate the dominance of short-range solvation in the rapid relaxation dynamics. In particular, the initial very rapid C(t) component for the smaller anion-neutral reactant pair is seen to arise chiefly from dissipation of the hydroxyl solvent polarization around the newly formed neutral site following ET, being accompanied by a slower build up of solvent structuring around the adjacent anionic site. The simulated ET reorganization energies are also shown to be dependent upon the reactant size and charge type. Some more general implications of these and other MD simulation results to the elucidation of dynamical solvent effects in activated ET processes are also noted.
Recognizing small-circuit structure in two-qubit operators

This work proposes numerical tests which determine whether a two-qubit operator has an atypically simple quantum circuit. Specifically, we describe formulas, written in terms of matrix coefficients, characterizing operators implementable with exactly zero, one, or two controlled-NOT (CNOT) gates and all other gates being one-qubit gates. We give an algorithm for synthesizing two-qubit circuits with an optimal number of CNOT gates and illustrate it on operators appearing in quantum algorithms by Deutsch-Josza, Shor, and Grover. In another application, our explicit numerical tests allow timing a given Hamiltonian to compute a CNOT modulo one-qubit gate, when this is possible.
Space-time analysis: HBT at SPS and RHIC

Abstract In this review talk, I first summarize the conclusions which can be drawn from a particle interferometric analysis of CERN SPS data and then I address related questions which are relevant for the upcoming experiments at RHIC.
A Simple Test for the Existence of Two Accretion Modes in Active Galactic Nuclei

By analogy to the different accretion states observed in black hole X-ray binaries (BHXBs), it appears plausible that accretion disks in active galactic nuclei (AGNs) undergo a state transition between a radiatively efficient and inefficient accretion flow. If the radiative efficiency changes at some critical accretion rate, there will be a change in the distribution of black hole masses and bolometric luminosities at the corresponding transition luminosity. To test this prediction, I consider the joint distribution of AGN black hole masses and bolometric luminosities for a sample taken from the literature. The small number of objects with low Eddington-scaled accretion rates < 0.01 and black hole masses MBH < 109 M? constitutes tentative evidence for the existence of such a transition in AGNs. Selection effects, in particular those associated with flux-limited samples, systematically exclude objects in particular regions of the (MBH, Lbol) plane. Therefore, they require particular attention in the analysis of distributions of black hole mass, bolometric luminosity, and derived quantities such as the accretion rate. I suggest further observational tests of the BHXB-AGN unification scheme that are based on the jet domination of the energy output of BHXBs in the hard state, and of the possible equivalence of BHXB in the very high (or steep power-law) state showing ejections and efficiently accreting quasars and radio galaxies with powerful radio jets.
When democratization radicalizes: The Kurdish nationalist movement in Turkey

This article addresses a historical puzzle: Why did the insurgent PKK (Partiya Karkeren Kurdistan), which was militarily defeated, which renounced the goal of secession, and whose leader was under the custody of the Turkish state, remobilize its armed forces in a time when opportunities for the peaceful solution of the Kurdish question were unprecedented in Turkey? The PKK’s radicalization at a period of EU-induced democratization in Turkey counters the conventional argument that fostering democracy would reduce the problems of ethnic conflict. Explanations based on resource mobilization, political opportunity structures, and cognitive framing fail to provide a satisfactory answer. The article argues that democratization will not necessarily facilitate the end of violent conflict as long as it introduces competition that challenges the political hegemony of the insurgent organization over its ethnic constituency. Under the dynamics of competition, the survival of the organization necessitates radicalization rather than moderation. As long as the insurgent organization successfully recruits new militants, democratization is not a panacea to violent conflict. The findings indicate that research on the micro-level dynamics of insurgency recruitment will contribute to a better understanding of ethnic conflict management. Data come from multiple sources including ethnographic fieldwork, statistical analyses of quantitative data (i.e. spatial clustering and ecological inference), and systematic reading of original documents.
Near-sighted superlens

We consider the problem of subwavelength imaging via a slab of a left-handed medium (LHM) in the presence of material losses. We derive the analytical expression for the resolution limit of a LHM-based lens and demonstrate that the area of its subwavelength performance is usually limited to the near-field zone.
2-mercaptobenzothiazole--an improved reagent for the removal of methyl phosphate protecting groups from oligodeoxynucleotide phosphotriesters.

Abstract An equimolar (1.5M) solution of 2-mercaptobenzothiazole and N,N-diisopropylethylamine in 1-methyl-2-pyrrolidinone efficiently removed the methyl phosphate protecting groups from deoxynucleotide phosphotriesters and yielded synthetic oligomers of high genetic integrity. This odorless reagent can therefore substitute for hazardous thiophenol usually used for this purpose.
Implicit Solvers for Unstructured Meshes

Implicit methods are developed and tested for unstructured mesh computations. The methods are used to solve the compressible Navier-Stokes equations to steady state. The approximate system which arises from the Newton linearization of the nonlinear evolution operator is solved by using the preconditioned GMRES (generalized minimum residual) technique. Three different preconditioners, namely, the incomplete LU factorization (ILU), block diagonal factorization, and the symmetric successive over-relaxation (SSOR) are investigated. The preconditioners have been optimized to have good vectorization properties. SSOR and ILU themselves are studied as iterative schemes. The various methods are compared over a wide range of problems. Ordering of the unknowns, which affects the convergence of these sparse matrix iterative methods, is also investigated. Results are presented for inviscid and turbulent viscous calculations on single and multi-element airfoil configurations using globally and adaptively generated meshes.
Real Polynomials with All Roots on the Unit Circle and Abelian Varieties over Finite Fields

Abstract In this paper we prove several theorems about abelian varieties over finite fields by studying the set of monic real polynomials of degree 2 n all of whose roots lie on the unit circle. In particular, we consider a set V n of vectors in R n that give the coefficients of such polynomials. We calculate the volume of V n and we find a large easily-described subset of V n . Using these results, we find an asymptotic formula—with explicit error terms—for the number of isogeny classes of n -dimensional abelian varieties over F q . We also show that if n >1, the set of group orders of n -dimensional abelian varieties over F q contains every integer in an interval of length roughly q n −(1/2) centered at q n +1 . Our calculation of the volume of V n involves the evaluation of the integral over the simplex {( x 1 , …, x n ) | 0⩽ x 1 ⩽…⩽ x n ⩽1} of the determinant of the n × n matrix [ x e i −1 j , where the e i are positive real numbers.
Glass Formation, Properties and Structure of Soda–Yttria–Silica Glasses

The glass formation region of the soda yttria silicate system was determined. The glasses within this region were measured to have a density of 2.4 to 3.1 g/cu cm, a refractive index of 1.50 to 1.60, a coefficient of thermal expansion of 7 x 10(exp -6)/C, softening temperatures between 500 and 780 C, and Vickers hardness values of 3.7 to 5.8 GPa. Aqueous chemical durability measurements were made on select glass compositions while infrared transmission spectra were used to study the glass structure and its effect on glass properties. A compositional region was identified which exhibited high thermal expansion, high softening temperatures, and good chemical durability.
On Spectral Hypergraph Theory of the Adjacency Tensor

We study both H and E/Z-eigenvalues of the adjacency tensor of a uniform multi-hypergraph and give conditions for which the largest positive H or Z-eigenvalue corresponds to a strictly positive eigenvector. We also investigate when the E-spectrum of the adjacency tensor is symmetric.
BATSE Observations of Gamma-Ray Burst Tails

With the discovery of low-energy radiation appearing to come from the site of gamma-ray bursts in the hours to weeks after the initial burst of gamma rays, it would appear that astronomers have seen a cosmological imprint made by the burster on its surroundings. I discuss in this paper the phenomenon of post-burst emission in BATSE (Burst and Transient Source Experiment) gamma-ray bursts at energies traditionally associated with prompt emission. By summing the background-subtracted signals from hundreds of bursts, I find that tails out to hundreds of seconds after the trigger may be a common feature of long events (duration greater than 2s), and perhaps of the shorter bursts at a lower and shorter-lived level. The tail component appears independent of both the duration (within the long GRB sample) and brightness of the prompt burst emission, and may be softer. Some individual bursts have visible tails at gamma-ray energies and the spectrum in at least a few cases is different from that of the prompt emission. Afterglow at lower energies was detected for one of these bursts, GRB-991216, raising the possibility of afterglow observations over large energy ranges using the next generation of GRB detectors in conjunction with sensitive space or ground-based telescopes.
Compiling Fresh Breeze Codelets

This paper presents the design of a compiler for parallel programs expressed as collections of codelets -- blocks of statements intended for distribution over the processing cores of a massively parallel computer system.Because interactions of codelets with other codelets are limited to acquiring input data at the start of execution and making results available on completion, an unconventional approach to code generation appears beneficial -- we call it code generation by program analysis and code construction. We present an implementation of this concept in the context of a compiler for functional dialects of the Java or Scala programming languages targeted to the proposed instruction set of a Fresh Breeze computer system architecture.
Sequestering in string theory

We study sequestering, a prerequisite for flavor-blind supersymmetry breaking in several high-scale mediation mechanisms, in compactifications of type IIB string theory. We find that although sequestering is typically absent in unwarped backgrounds, strongly warped compactifications do readily sequester. The AdS/CFT dual description in terms of conformal sequestering plays an important role in our analysis, and we establish how sequestering works both on the gravity side and on the gauge theory side. We pay special attention to subtle compactification effects that can disrupt sequestering. Our result is a step toward realizing an appealing pattern of soft terms in a KKLT compactification.
Cluster Transfer Matrix Method for the Single Electron Box

With the newly developed cluster transfer matrix method, we calculate the average electron number n vs nx (the polarization charge) for varying junction conductance and its first derivative at nx=0 for finite temperatures, and demonstrate that the new method is as powerful as the Monte Carlo and renormalization group methods.
Sensitivity Evaluation of a Transport-Based Turbulent Cavitation Model

A sensitivity analysis is done for turbulent cavitating flows using a pressure -based Navier-Stokes solver coupled with a phase volume fraction transport model and non-equilibrium k-e turbulence closure. Four modeling parameters are adopted for evaluation, namely, Ce1 and Ce2, which directly influences the production and dissipation of turbulence kinetic energy, and Cdest and Cprod, which regulate the evaporation and condensation of the phases. Response surface methodology along with design of experiments is used for the sensitivity studies. The difference between the computational and experimental results is used to judge the model fidelity. Under non-cavitating conditions, the best selections of Ce1 and Ce2, exhibit a linear combination with multiple optima. Using this information, cavitating flows around an axi -symmetric geometry with a hemispherical fore-body and the NACA66(MOD) airfoil are assessed. Analysis of the cavitating model shows that the favorable combinations of Cdest and Cprod, are inversely proportional to each other for the geometries considered. A set of cavitation numbers is selected for each of the geometries to demonstrate the predictive capability of the present modeling approach for attached, turbulent cavitating flows.
Identifying the competition

We propose a utility method of identifying the set of competitors that a product faces. We apply the method to the 1987 U.S new automobile market.
A Comparison between Active and Passive Sensing of Soil Moisture from Vegetated Terrains

A comparison between active and passive sensing of soil moisture over vegetated areas is studied via scattering models. In active sensing, three contributing terms to radar backscattering can be identified: 1a) the ground surface scatter term; 2a) the volume scatter term representing scattering from the vegetation layer; and 3a) the surfacevolume. scatter term accounting for scattering from both surface and volume. In emission, three sources of contribution can also be identified: 1b) surface emission, 2b) upward volume emission from the vegetation layer, and 3b) downward volume emission scattered upward by the ground surface. As ground moisture increases, terms 1a) and 3a) increase due to increase in permittivity in the active case. However, in passive sensing, term 1b) decreases but term 3b} increases for the same reason. This self-compensating effect produces a loss in sensitivity to change in ground moisture. Furthermore, emission from vegetation may be larger than that from the ground. Hence, the presence of vegetation layer causes a much greater loss of sensitivity to passive than active sensing of soil moisture.
Divalent and Multivalent Activation in Phosphate Triesters: A Versatile Method for the Synthesis of Advanced Polyol Synthons

The construction of mono- and bicyclic phosphate trimesters possessing divalent and multivalent activation and their subsequent use in the production of advanced polyol synthons is presented. The method highlights efforts to employ phosphate tethers as removable, functionally active tethers capable of multipositional activation and their subsequent role as leaving groups in selective cleavage reactions. The development of phosphate tethers represents an integrated platform for a new and versatile tether for natural product synthesis and sheds light on new approaches to the facile construction of small molecules.
A characterization of Conway's group .3

Abstract Let .3 be the simple group discovered by J. H. Conway (5). Let C0 be the centralizer of an involution in the center of a Sylow 2-subgroup of .3. The group C0 is used to characterize the group .3; namely, we prove the following: Main Theorem . Let G be a finite group with the following properties: (i) G has an involution s with CG(s) ≅ C0 (ii) G ≠ CG(s) · O(G). Then G ≅ .3. In particular, .3 is the only simple group satisfying (i). In the process of proving the Main Theorem, we obtain the character table of .3, describe the local structure of .3, and prove that .3 has no outer automorphisms.
Finite volume solution of the two-dimensional Euler equations on a regular triangular mesh

The two-dimensional Euler equations have been solved on a triangular grid by a multigrid scheme using the finite volume approach. By careful construction of the dissipative terms, the scheme is designed to be secondorder accurate in space, provided the grid is smooth, except in the vicinity of shocks, where it behaves as firstorder accurate. In its present form, the accuracy and convergence rate of the triangle code are comparable to that of the quadrilateral mesh code of Jameson.
Improving thermal ablation delineation with electrode vibration elastography using a bidirectional wave propagation assumption

Thermal ablation procedures are commonly used to treat hepatic cancers and accurate ablation representation on shear wave velocity images is crucial to ensure complete treatment of the malignant target. Electrode vibration elastography is a shear wave imaging technique recently developed to monitor thermal ablation extent during treatment procedures. Previous work has shown good lateral boundary delineation of ablated volumes, but axial delineation was more ambiguous, which may have resulted from the assumption of lateral shear wave propagation. In this work, we assume both lateral and axial wave propagation and compare wave velocity images to those assuming only lateral shear wave propagation in finite element simulations, tissue-mimicking phantoms, and bovine liver tissue. Our results show that assuming bidirectional wave propagation minimizes artifacts above and below ablated volumes, yielding a more accurate representation of the ablated region on shear wave velocity images. Area overestimation was reduced from 13.4% to 3.6% in a stiff-inclusion tissue-mimicking phantom and from 9.1% to 0.8% in a radio-frequency ablation in bovine liver tissue. More accurate ablation representation during ablation procedures increases the likelihood of complete treatment of the malignant target, decreasing tumor recurrence.
Representations of quiver Hecke algebras via Lyndon bases

A new class of algebras has been introduced by Khovanov and Lauda and independently by Rouquier. These algebras categorify one-half of the Quantum group associated to arbitrary Cartan data. In this paper, we use the combinatorics of Lyndon words to construct the irreducible representations of those algebras associated to Cartan data of finite type. This completes the classification of simple modules for the quiver Hecke algebra initiated by Kleshchev and Ram.
Soft Pion Emission Induced by Electromagnetic and Weak Interactions

We consider some extensions of the relation which has been obtained by Nambu and Luri\'e between an elastic process and the accompanying soft pion emission process under the assumption of approximate ${\ensuremath{\gamma}}_{5}$ invariance. In particular, a generalized formula is found which enables one to describe the electropion production $e+N\ensuremath{\rightarrow}N+e+\ensuremath{\pi}$ and the neutrino-pion production $\ensuremath{\nu}+N\ensuremath{\rightarrow}N+e+\ensuremath{\pi}$ at the threshold of $N\ensuremath{\pi}$ system in terms of the vector (Hofstadter) and the axial-vector form factors. Explicit forms of the cross sections are given.
TARGET CHARACTERIZATION USING TIME-REVERSAL SYMMETRY OF WAVE PROPAGATION

Over the last 15 years, there has been rapid growth in applications of time-reversal symmetry of wave propagation to enhance communications and imaging through highly scattering media. These techniques exploit both temporal and spatial reciprocity to mitigate signal distortion created from the large number of independent propagation paths between a transmitter and receiver. The time-reversal process is often described by the time-reversal operator (TRO), or equivalently by the multistatic response matrix (MRM), defined by the transmit and receive system. A singular value decomposition of this operator (or MRM) is the starting point for many of the time-reversal imaging techniques. In addition to imaging, this decomposition can also be used to extract information about objects embedded within the propagation medium, i.e., target characterization. In this paper, we review the development of target characterization in time-reversal, with an emphasis on extracting information from small targets. We will analyze the MRM for both acoustic and electromagnetic scattering and show how the symmetry of the target is reflected in the properties of the singular value spectrum. Finally, we discuss several open problems and potential applications.
An asymmetric synthesis (−)-epibatidine

Abstract A Pd catalyzed desymmetrization of cis-3,6-dibenzoyloxy-2-cyclohexene and a Pd catalyzed cross-coupling constitute key reactions in a synthesis of the non-opioid analgesic (−)-epibatidine.
Tunnel diode/transistor differential comparator

A new tunnel diode/transistor circuit topology is reported, which both increases speed and reduces power in differential comparators. This circuit topology is of special interest for use in direct digital synthesis applications. The circuit topology can be extended to provide performance improvements in high speed logic and signal processing applications. The circuits are designed based on InP/GaAsSb double heterojunction bipolar transistors and AlAs/InGaAs/AlAs resonant tunneling diodes. A self-aligned and scalable fabrication approach using nitride sidewalls and chemical mechanical polishing is outlined.
Thiophene, 2,3- and 2,5-dihydrothiophene, and tetrahydrothiophene hydrodesulfurization on Mo and Re γ-Al2O3 catalysts

Abstract Comparative studies of the hydrodesulfurization (HDS) of thiophene, 2,3-dihydrothiophene, 2,5-dihydrothiophene and tetrahydrothiophene were performed using Mo γ- Al 2 O 3 and Re γ- Al 2 O 3 catalysts. Reaction pathways for interconversion of the organosulfur compounds were shown to exist. Both dihydrothiophene compounds were highly reactive and formed significant amounts of 1,3-butadiene at 300 °C over Re catalysts. The dihydrothiophenes are proposed to be possible reaction intermediates for thiophene HDS.
The signature of a black hole transit

This paper considers the possibility of identifying a black hole on the basis of the detection of some unique effect occurring during the transit of a black hole across the stellar disk of a companion star in a binary system. The results of Monte-Carlo calculations show that the amplitude of the photometric and polarimetric light curves in a typical X-ray binary is too small to be observed with present instrumentation, but that a black hole transit might be detectable in a binary having a large separation of the components. No binary system suggested as containing a stellar-mass-sized black hole is a like candidate to exhibit an observable transit signature, with the possible exception of X Persei/4U0352+30 described by White et al. (1976).
Shape optimization of three-dimensional folded-plate structures

The basic features of a previously described shape optimization capability included a general geometric problem description format and adaptive finite element analysis. The finite element mesh for each design step was created from the boundary information only and refined using finite element solution results. At that time, only structures in a single plane could be treated. This work has now been extended to handle structures created from an assembly of segments that may be rotated into any plane as well as to contain the nonplanar surface curvature within any segment. In order to handle these more general problems, it was necessary to introduce a more efficient mesh generation scheme. Several design examples are presented to demonstrate each of the features.
The repeatability of diagnostic tests and surveys in dry eye.

In the clinical evaluation of dry eye, many diagnostic tests are utilized in making a dry eye diagnosis. Unfortunately, a single “gold standard” diagnostic test does not exist. 1 While the repeatability of many of the clinical tests used to diagnose dry eye have been assessed in normal patients, the repeatability of these tests and of surveys used in dry eye diagnosis has not been evaluated in dry eye patients. In addition to the battery of clinical diagnostic tests assessed in this study, two surveys were evaluated: McMonnies’s Dry Eye Questionnaire was developed to assess likelihood of dry eye, 2 and the National Eye Institute Visual Function Questionnaire (NEI-VFQ-25)3.4 was developed to assess vision-specific quality of life. However, the ocular pain subscale of the latter can be used as an indication of dry eye symptoms. In this study, the repeatability of a battery of dry eye diagnostic tests, the McMonnies’s dry eye questionnaire, and the NEI-VFQ-25 were assessed on a sample of dry eye patients.
Heat transfer enhancement techniques for Space Station cold plates

Two attachment techniques for mounting electronic equipment to Space Station cold plates were analyzed and compared using thin foils of lead, tin, aluminum, and copper to enhance the thermal contact conductance. The two techniques evaluated included a 70- x 70-mm bolted attachment technique and an attachment scheme using an inflatable bladder. The results indicate that, even in the presence of the metallic foils, the bolted technique results in large variations in the local thermal contact conductance over the surface of the cold plate, whereas the pressurized bladder yields more uniform local contact conductance values. The results indicated that the lead foil provided an enhancement factor of approximately 3, the tin foil an enhancement factor of approximately 1.5, the aluminum an enhancement factor of approximately 1.0, and the copper an enhancement factor of approximately 0.9.
On the Study of Jamming Percolation

We investigate kinetically constrained models of glassy transitions, and determine which model characteristics are crucial in allowing a rigorous proof that such models have discontinuous transitions with faster than power law diverging length and time scales. The models we investigate have constraints similar to that of the knights model, introduced by Toninelli, Biroli, and Fisher (TBF), but differing neighbor relations. We find that such knights-like models, otherwise known as models of jamming percolation, need a “No Parallel Crossing” rule for the TBF proof of a glassy transition to be valid. Furthermore, most knights-like models fail a “No Perpendicular Crossing” requirement, and thus need modification to be made rigorous. We also show how the “No Parallel Crossing” requirement can be used to evaluate the provable glassiness of other correlated percolation models, by looking at models with more stable directions than the knights model. Finally, we show that the TBF proof does not generalize in any straightforward fashion for three-dimensional versions of the knights-like models.
A mixed-signal RAM decision-feedback equalizer for disk drives

A mixed-signal RAM decision-feedback equalizer (DFE) that operates at 90 Mb/s is described. In the analog domain, the DFE subtracts intersymbol interference caused by the past four outputs. The equalized signal is fed into a nonuniform flash analog-to-digital converter (ADC) to produce the decision output and error signal used to adapt the RAM contents in the digital domain. With a 5 V supply voltage, the power dissipation is 260 mW during steady-state operation. The active area is 4.5 mm/sup 2/ in a 1 /spl mu/m CMOS process.
Effects of laser triggering parameters on runtime and jitter of a gas switch

Parameters affecting the runtime and jitter of a laser triggered gas switch have been studied. Experiments tested a variety of switch parameters including percentage of selfbreak and switch pressure. The effects of laser beam parameters were also considered, including focal length, laser energy, laser spark length, and laser wavelength. Experiments were performed on the Tiger pulsed power machine. Measurements were taken on a spark gap switch built from the trigger section of a Rimfire switch. A Marx bank consisting of 32, 3.1 uF, capacitors that fed into a 7 nF intermediate storage capacitor was used to drive the switch into a 4 ? resistive load. The test switch was pressurized to 306 kPa (30 psig) with SF6 and operated near 1 MV. A New Wave Tempest Nd:YAG laser was used to trigger breakdown of the switch. The laser was focused at the mid-gap between the switch electrodes using lenses with focal lengths between 30 cm and 100 cm. Focused laser energy in the switch ranged from <5 mJ to 80 mJ. The effects of switch and laser beam parameters on the runtime and jitter of a laser triggered gas switch are presented. The end goal of the research is to determine optimal conditions for improved switch performance.