cssi/SciSciGPT-SciSciNet huggingface dataset:
Small-scale variability in Saturn’s lower ionosphere

Abstract We perform and present a wavelet analysis on all 31 Cassini electron density profiles published to date (Nagy, A.F. et al. [2006]. J. Geophys. Res. 111 (A6), CiteID A06310; Kliore, A.J. et al. [2009]. J. Geophys. Res. 114 (A4), CiteID A04315). We detect several discrete scales of variability present in the observations. Small-scale variability (S In the second part of the paper we present a gravity wave propagation/dissipation model for Saturn’s upper atmosphere and compare the wave properties to the characteristics of the observed electron density variability at different scales. The general features observed in the data are consistent with gravity waves being present in the lower ionosphere and causing layering of the ions and the electrons. The wave-driving mechanism provides a simultaneous explanation for several of the properties of the observed variability: (i) lack of variability in the electron density above the predicted region of wave dissipation; (ii) in most cases the peak amplitude of variability occurs within the altitude range for dissipation of gravity waves or below; (iii) shorter scales have smaller amplitudes than the longer scales; (iv) shorter scales are present at lower altitudes whereas longer scales persist to higher altitudes; and (v) several layers often form a system of equally spaced maxima and minima that can be traced over a large altitude range.
Jump risk, stock returns, and slope of implied volatility smile

Abstract In the presence of jump risk, expected stock return is a function of the average jump size, which can be proxied by the slope of option implied volatility smile. This implies a negative predictive relation between the slope of implied volatility smile and stock return. For more than four thousand stocks ranked by slope during 1996–2005, the difference between the risk-adjusted average returns of the lowest and highest quintile portfolios is 1.9% per month. Although both the systematic and idiosyncratic components of slope are priced, the idiosyncratic component dominates the systematic component in explaining the return predictability of slope. The findings are robust after controlling for stock characteristics such as size, book-to-market, leverage, volatility, skewness, and volume. Furthermore, the results cannot be explained by alternative measures of steepness of implied volatility smile in previous studies.
A bulky silyl derivative of tin(II)

Abstract The reaction of SnCl2 with Li[Si(SiMe3)3] · 3THF in Et2O at − 78°C affords [(Me3Si)3Si]2Sn(μ-Cl)Li(THF)3, the structure of which has been established by X-ray crystallography.
Galaxies at z 4 and the Formation of Population II

We report the discovery of four high-redshift objects (3.3 3 galaxies. Star formation rates range from 2.5(7.8) h-2 to 22.(78.) h-2 M☉ yr-1, for q0 = 0.5(0.05), depending on assumptions about gravitational lensing and extinction, also typical of other z > 3 galaxies. These objects are tentatively identified as the low-metallicity protospheroid clumps that will merge to form the Population II components of today's spheroids.
Bubbling AdS space and 1/2 BPS geometries

We consider all 1/2 BPS excitations of AdS × S configurations in both type-IIB string theory and M-theory. In the dual field theories these excitations are described by free fermions. Configurations which are dual to arbitrary droplets of free fermions in phase space correspond to smooth geometries with no horizons. In fact, the ten dimensional geometry contains a special two dimensional plane which can be identified with the phase space of the free fermion system. The topology of the resulting geometries depends only on the topology of the collection of droplets on this plane. These solutions also give a very explicit realization of the geometric transitions between branes and fluxes. We also describe all 1/2 BPS excitations of plane wave geometries. The problem of finding the explicit geometries is reduced to solving a Laplace (or Toda) equation with simple boundary conditions. We present a large class of explicit solutions. In addition, we are led to a rather general class of AdS5 compactifications of M-theory preserving = 2 superconformal symmetry. We also find smooth geometries that correspond to various vacua of the maximally supersymmetric mass-deformed M2 brane theory. Finally, we present a smooth 1/2 BPS solution of seven dimensional gauged supergravity corresponding to a condensate of one of the charged scalars.
MR Imaging of Pediatric Trauma

Although plain radiography remains the most important and cost-effective imaging for screening and characterizing osseous injuries, it has been well recognized that pediatric fractures can occur without radiographic abnormalities. The superb capability of MR imaging in demonstrating marrow edema, cartilage defects, and soft tissue injuries makes it an essential adjunct in the further evaluation of trauma to the growing skeleton. The key MR imaging findings of growth plate injuries, stress fractures, avulsion injuries, osteochondritis dissecans, transient patellar dislocation, and soft tissue injuries are described in this article.
Cohomological descent on the overconvergent site

We prove that cohomological descent holds for finitely presented crystals on the overconvergent site with respect to proper or fppf hypercovers.
The Specialist's Discretion: Stopped Orders and Price Improvement

When a market order arrives, the NYSE specialist can offer a price one tick better than the limit orders on the book and trade for his own account. Alternatively, the specialist can "stop" the market order, which means he guarantees execution at the current quote but provides the possibility of price improvement. My model shows that specialists can use stops to sample the future order flow before making a commitment to trade. I present empirical evidence that both stops and immediate price improvement impose adverse selection costs on limit order traders. Article published by Oxford University Press on behalf of the Society for Financial Studies in its journal, The Review of Financial Studies.
Solvent, chelation and concentration effects on the benzannulation reaction of chromium carbene complexes and acetylenes

The reactions of a number of chromium carbene complexes (CO)5CrC(OMe)R (R = Ph, o-OMePh, p-OMePh, o-O-tBuPh, 1-C6H9, 1-C5H7O) were examined with a variety of acetylenes (R′CCR2, R1, R2 = H, Me, Et, n-Pr, Ph, SiMe3) in solvents ranging from low to high coordinating ability. The high selectivity for the benzannulated product from the reactions of simple α,β-unsaturated complexes is not affected by changes in solvent or substituents on the acetylene. The reactions of aryl complexes with acetylenes are quite sensitive to the nature of the solvent and the acetylene. The highest selectivities and efficiencies for the benzannulated product from the reactions of aryl complexes are with solvents of low coordinating ability. Solvents with intermediate coordinating ability and small size give high selectivity for cyclobutenone formation for reactions with disubstituted acetylenes. Solvents with high coordinating ability give the least selective reactions and a considerable amount of indene products. An o-methoxy group on the aryl substituent of the carbene complex can chelate to the metal center during the course of the benzannulation reaction and, in acetonitrile, alter the product distribution in favor of the cyclobutenone product. An amino substituted complex, (CO)5 CrC(NMe2)Ph, was found to react with diethylacetylene in THF to give indene products. The reactions of aryl complexes with alkynes can be accelerated by ultraviolet irradiation which results in high selectivity for the benzannulated product at as low a temperature as −78°C, and high selectivity for indene products for those complexes having a chelating group (methoxy) on the aryl ring. Finally, the product distribution from the reaction of the o-methoxyphenyl complex with diethylacetylene was found to be dependent on alkyne concentration, a phenomenon not previously observed for the reactions of carbene complexes and acetylenes.
Postoperative pain following outpatient pediatric urologic surgery: A comparison of anesthetic techniques*

Abstract Objectives. To evaluate and compare the efficacy of caudal and local nerve blocks in preventing pain following outpatient pediatric urologic surgery. Methods. Seventy-seven boys undergoing outpatient urologic surgery were randomized into one of three groups: general anesthesia alone, general anesthesia and caudal nerve block, or general anesthesia and local nerve block. Pain scores, frequency of medication, and total dosage of medication were recorded in the immediate postoperative period. Long-term pain and discomfort were measured using â 24-hour and 1-week questionnaire. Results. The caudal and local groups had lower pain scores and significantly lower medication requirements than the control group in the short-term postoperative period. The caudal group had lower pain scores than the local group in all categories; however, the only significant difference was at 24 hours postoperatively. At 1 week postoperatively, the only difference among the three groups was a lower pain score in the caudal group compared with the control group. Conclusions. This study demonstrates that for outpatient pediatric urologic procedures,both caudal and local nerve blocks significantly reduce pain and medication given in the immediate postoperative period and indicates that caudal block may decrease pain for up to 1 week following surgery.
Replacing Standard Galaxy Profiles with Mixtures of Gaussians

ABSTRACT.Exponential, de Vaucouleurs, and Sersic profiles are simple and successful models for fitting two-dimensional images of galaxies. One numerical issue encountered in this kind of fitting is the pixel rendering and convolution (or correlation) of the models with the telescope point-spread function (PSF); these operations are slow, and easy to get slightly wrong at small radii. Here we exploit the realization that these models can be approximated to arbitrary accuracy with a mixture (linear superposition) of two-dimensional Gaussians (MoGs). MoGs are fast to render and fast to affine-transform. Most importantly, if you have a MoG model for the pixel-convolved PSF, the PSF-convolved, affine-transformed galaxy models are themselves MoGs and therefore very fast to compute, integrate, and render precisely. We present worked examples that can be directly used in image fitting; we are using them ourselves. The MoG profiles we provide can be swapped in to replace the standard models in any image-fitting co...
Global climate change and active tectonics: effective tools for teaching and research

Abstract Multidisciplinary student teams foster innovative research projects that can discern the locations, times, and styles of late Quaternary faulting. Field studies in the area of the 1992 Landers magnitude 7.3 earthquake in southeastern California provide excellent opportunities for teaching and research in climatic and tectonic geomorphology. Graduate-student work begins with descriptions of type sections for mappable units of Quaternary alluvium — climate-change induced aggradation events. These are stair-stepped flights of alluvial fan and terrace surfaces. Topographic profiles along faulted stream channels and fans provide estimates of vertical tectonic deformation, and insight into the responses of fluvial systems to wrench-fault tectonics. Time lines in this tectonically deforming landscape are the result of global climate changes that caused synchronous pulses of alluviation in the Mojave Desert at about 125, 55, and 10 (12 and 8) ka. These dated alluvial surfaces record tectonic deformation resulting from cumulative Late Quaternary surface ruptures. Tectonic geomorphologic analyses use topographic, pedogenic, stratigraphic, and structural data, but do not require expensive and time-consuming trenching projects. Ages of faulted and unfaulted alluvium constrain the dates of two pre-1992 earthquakes. The 1992 Landers event is not characteristic of earlier faulting because it ruptured through adjacent segments of the Emerson fault that previously ruptured in separate events; one at 3 −1 +2 ka, and the other before 8 ka. Styles of tectonic deformation and locations of active faults, however may not have changed during the past 125 ka.
A Simple Cointegrating Rank Test Without Vector Autoregression

This paper proposes a fully nonparametric test for cointegrating rank which does not require estimation of a vector autoregressive model. The test exploits the fact that the degeneracy in the moment matrix of the variables with mixed integration order corresponds to the notion of cointegration. With an appropriate standardization, the test statistics are shown to have a nuisance parameter free limiting distribution and to be consistent under reasonable conditions. Monte Carlo experiments suggest that the finite sample performance of the test is satisfactory. The proposed tests are applied to the stochastic growth model using the US aggregate data.
Reduction Potentials of Naphthoxyl and Pyridoxyl Radicals in Aqueous Solutions

Reduction potentials of 1- and 2-naphthoxyl, 2-, 3-, and 4-pyridoxyl, and 4-phenylphenoxyl radicals in alkaline aqueous solutions are determined by pulse radiolysis. The potential of 1-naphthoxyl i...
Modeling core collapse supernovae in 2 and 3 dimensions with spectral neutrino transport

The overwhelming evidence that the core collapse supernova mechanism is inherently multidimensional, the complexity of the physical processes involved, and the increasing evidence from simulations that the explosion is marginal presents great computational challenges for the realistic modeling of this event, particularly in 3 spatial dimensions. We have developed a code scalable to computations in 3 dimensions that couples PPM Lagrangian-withremap hydrodynamics, multigroup flux-limited diffusion neutrino transport (with many improvements), and a nuclear network. The neutrino transport is performed in a ''ray-by-ray-plus'' approximation, wherein all the lateral effects of neutrinos are included (e.g., pressure, velocity corrections, advection) except lateral transport. A moving radial grid option permits the evolution to be carried out from initial core collapse with only modest demands on the number of radial zones. The inner part of the core is evolved after collapse, along with the rest of the core and mantle, by subcycling the lateral evolution near the center as demanded by the small Courant times. We present results of 2-D simulations of a symmetric and an asymmetric collapse of both a 15 and an 11 M⊙ progenitor. In each of these simulations we have discovered that once the oxygen-rich material reaches the shock there is a synergistic interplay between the reduced ram pressure, the energy released by the burning of the shock-heated oxygen-rich material, and the neutrino energy deposition that leads to a revival of the shock and an explosion.
Small cell undifferentiated (neuroendocrine) carcinoma of the uterine cervix

Abstract Background Small cell undifferentiated (neuroendocrine) carcinoma of the cervix is a rare and agressive tumor. Most medical centers have little experience with this tumor. The purposes of our study were to evaluate our experience and compare our findings with those reported in current literature. Study design Fifteen patients with small cell undifferentiated carcinoma of the cervix were treated between 1977 and 1997. Clinical data including age, pregnancy history, tumor stage, recurrence, type of therapy, presenting symptoms, location of metastasis, and survival were studied. Results The ages of patients ranged from 20 to 83 years, with a mean of 47 years. Two patients were nulliparous, 2 primiparous, and 11 multiparous. Five patients (33%) were stage I, three (20%) stage II, one (7%) stage III, and six (40%) stage IV at diagnosis. Five patients (33%) progressed without response to treatment, and seven (47%) experienced a recurrence of their cancer, on average after 15 months. Treatments included surgery, radiation, chemotherapy, or a combination of them. Extrapelvic metastases developed in five patients with stage I or stage II disease. Three patients (20%) developed brain metastasis. Tumor lysis syndrome was encountered in one patient. Thirteen patients died of their disease, one remained alive 80 months after diagnosis, and one was lost to followup. Conclusions Our experience with this rare and aggressive tumor raises the question of increased incidence of central nervous system metastases with small cell undifferentiated carcinoma. Present therapy has not significantly improved outcomes. Tumor lysis syndrome is a possible risk when treating these patients.
Fuzzy Damage Mitigating Control of Mechanical Structures

This paper presents the architecture and synthesis of a damage mitigating control system for mechanical structures where the objective is to achieve high performance with increased reliability, availability, component durability, and maintainability. The proposed control system has a two-tier structure. In the lower tier a linear sampled-data controller tracks a reference trajectory vector while the upper tier contains a fuzzy-logic-based damage controller which makes a trade-off between system performance and the damage in critical components. The synthesis procedure is demonstrated by simulation experiments on the model of a reusable rocket engine. The simulation results explore the feasibility of automatically regulating the damage/ performance trade-off in a real-time setting.
On the structure of Hermitian codes and decoding for burst errors

In this paper, it is proved that Hermitian code is a direct sum of concatenated Reed-Solomon codes over GF(q/sup 2/). Based on this discovery, first, a new method for computing the dimension and tightly estimating the minimum distance of the Hermitian code is derived. Secondly, a new decoding algorithm, which is especially effective in dealing with burst errors with complexity O(n/sup 5/3/), is described. Finally, some possible approaches for optimization of Hermitian codes are discussed.
Bureaucratic corruption, environmental policy and inbound US FDI: theory and evidence

Abstract Previous studies have proposed that equilibrium capital flows are affected by environmental regulations—the commonly coined ‘pollution haven’ hypothesis. We revisit this issue by treating environmental policies as endogenous and allowing governmental corruption to influence foreign direct investment patterns. Via these two simple extensions, we are able to provide a much richer model of international capital flows. The theoretical model presumes that the effect of corruption on FDI operates via two channels: corruption affects capital flows through its impact on environmental policy stringency and due to greater theft of public funds earmarked for public spending. We empirically examine the implications of the model using US state-level panel data from four industrial sectors over the period 1977–1987. Empirical results suggest environmental policy and corruption both play a significant role in determining the spatial allocation of inbound US FDI. In addition, the estimated effect of environmental policy is found to depend critically on exogeneity assumptions.
Permutation routing on reconfigurable meshes

In this paper we present efficient algorithms for packet routing on the reconfigurable linear array and the reconfigurable two-dimensional mesh. We introduce algorithms that are efficient in the worst case and algorithms that are better on average. The time bounds presented are better than those achievable on the conventional mesh and previously known algorithms. We present two variants of the reconfigurable mesh. In the first model, M r , the processors are attached to a reconfigurable bus, the individual edge connections being bidirectional. In the second model, M mr , the processors are attached to two unidirectional buses. In this paper we present lower bounds and nearly matching upper bounds for packet routing on these two models. As a consequence, we solve two of the open problems mentioned in [9].
Commercial bank mutual fund activities: Implications for bank risk and profitability

Abstract This paper examines the risk structure of bank holding companies and the effect of mutual fund activities on bank risk and profitability over the period 1987–1994. Findings from structural change tests indicate a significant decline in bank risk occurred near the mid-point of the study. Results from a confirmatory factor analytic model employed to examine the impact of mutual fund activities on banks suggest that mutual fund activities moderated bank industry systematic risk during the sample period. Mutual fund activities also increased the profitability of banks. These results suggest that mutual funds represent a productive avenue of expansion for bank holding companies.
A study to determine the characteristic shapes of helicopter visual approach profiles

Prior to this study, the characteristic shape of visual approach profiles had not been formally documented. In this study, over 200 visual approaches were flown using different helicopter types, test subjects, and initial conditions, and the altitude and groundspeed profiles were measured by a precision tracking radar. The data from each approach were then processed, and the characteristic shape of the altitude, groundspeed, and deceleration profiles was determined for each set of initial conditions. These flight data were processed further using graphical analysis techniques and parameterization which, in turn, led to developing closed-form equations that accurately describe the characteristic groundspeed and deceleration profiles. Results from this study can be used to select instrument approach profiles, to develop instrument approach control laws, and to define the corresponding hardware requirements.
Set-Oriented Retrieval.

Abstract The broad way in which we look at how an IRS functions influences the types of questions we ask about it and the ways we try to improve performance. In the recent past, retrieval methodologies have been based on retrieving documents one at a time. In this paper we are introducing a set-oriented view. We observe that this view is quite consistent with the single-document or sequential methods, and define a precise model to capture the set-oriented approach. We then examine a number of consequences of the model, such as the limitations implied by a finite index vocabulary. Finally, we discuss various ways in which the set orientation can influence our thinking about IR.
Solar eclipse monitoring for solar energy applications

Abstract In recent years, the interest in using solar energy as a major contributor to renewable energy applications has increased, and the focus to optimize the use of electrical energy based on demand and resources from different locations has strengthened. This article includes a procedure for implementing an algorithm to calculate the Moon’s zenith angle with uncertainty of ±0.001° and azimuth angle with uncertainty of ±0.003°. In conjunction with Solar Position Algorithm, the angular distance between the Sun and the Moon is used to develop a method to instantaneously monitor the partial or total solar eclipse occurrence for solar energy applications. This method can be used in many other applications for observers of the Sun and the Moon positions for applications limited to the stated uncertainty.
Stepwise Unwinding of Polyelectrolytes under Stretching

We consider the unwinding of a tethered, flexible, and weakly charged polyelectrolyte in a salt-free poor solvent under an externally imposed strain. Using scaling arguments, we predict that the restoring force of a stretched polyelectrolyte shows a sawtooth pattern as a function of the externally imposed end-to-end distance. This nonmonotonic behavior arises from a cascade of conformational transitions between necklace-like structures with different number of beads. The transitions result from the interplay between the unscreened Coulomb repulsion of charged monomers and the short-range attraction of the backbone.
Delayed hard photons from gamma-ray bursts

The delayed hard (up to 25 GeV) photons observed more than an hour following a gamma-ray burst on 1994 February 17 may result from the collisions of relativistic nucleons with a dense cloud, producing pi(0). The required cloud density is approx. 2 x 10(exp 11)/cu cm. This cloud may be the remains of the disrupted envelope of a neutron star, and may survive as an excretion disk of approx. 10(exp 14) - 10 (exp 15) cm radius around the coalescing binary.
Theoretical Investigation of a UV Laser Triggered Spark Gap

A model of a spark gap used as a shorting switch in a Blumlein pulsed power system has been developed. The spark gap is a gas-filled switch that is triggered by an ultraviolet laser pulse. Methods of reducing the rate at which the resistance of the arc falls are the focus of this investigation. The model consists of two separate parts: a kinetic model, which shows the formation of the plasma streamer, and a fluid model, which describes the behavior of the arc after the connection is made. The kinetic model results represent the initial conditions of the arc described by the fluid model. Increases in the initial radius of the arc resulted in lower resistance for the first 10 ns after the connection is made, while changes in conductivity showed a consistent reduction of the current throughout the life of the arc. Reorienting the laser trigger spot yielded the most significant increase in the initial radius of the streamer, 25%.
Spectral Measurements in a Disturbed Boundary Layer over Snow

Abstract I have measured time series of the turbulent fluctuations in longitudinal (u) and vertical (w) velocity and in temperature (t) and humidity (q) with fast-responding sensors in the near-neutrally stable surface layer over a snow-covered field. The series yielded individual spectra, u-w, w-t, w-q, and t-q cospectra and phase and coherence spectra for nondimensional frequencies (fz/U) from roughly 0.001 to 10. This is, thus, one of the most extensive spectral sets over collected over a snow-covered surface. With the exception of the u-w cospectra, all of the spectra and cospectra displayed the expected dependence on frequency in an inertial or inertial-convective subrange. All, however, contained significantly move energy at low frequency than the Kansas neutral-stability spectra and cospectra. This excess low-frequency energy and the erratic behavior of the u-w cospectra imply that the forested bills bordering the site on two sides were producing disturbances in the flow field at scales roughly equ...
Perspectives of positron annihilation spectroscopy in heterogeneous catalysis

Abstract The use of polychromatic positron annihilation spectroscopy (PAS) in heterogeneous catalysis is reviewed and its potential applications are discussed. This review covers early and current studies of catalytic oxides and supported metals, refers to the potential use of PAS in the characterization of catalytic sites, and outlines the future of the technique.
Anton, a special-purpose machine for molecular dynamics simulation

The ability to perform long, accurate molecular dynamics (MD) simulations involving proteins and other biological macro-molecules could in principle provide answers to some of the most important currently outstanding questions in the fields of biology, chemistry, and medicine. A wide range of biologically interesting phenomena, however, occur over timescales on the order of a millisecond---several orders of magnitude beyond the duration of the longest current MD simulations. We describe a massively parallel machine called Anton, which should be capable of executing millisecond-scale classical MD simulations of such biomolecular systems. The machine, which is scheduled for completion by the end of 2008, is based on 512 identical MD-specific ASICs that interact in a tightly coupled manner using a specialized highspeed communication network. Anton has been designed to use both novel parallel algorithms and special-purpose logic to dramatically accelerate those calculations that dominate the time required for a typical MD simulation. The remainder of the simulation algorithm is executed by a programmable portion of each chip that achieves a substantial degree of parallelism while preserving the flexibility necessary to accommodate anticipated advances in physical models and simulation methods.
Spatial frames of reference in Yucatec: Referential promiscuity and task-specificity

Abstract A referential communication task conducted with five pairs of native speakers of Yucatec Maya produced evidence of “referential promiscuity”, the unrestricted availability of spatial frames of reference (FoRs) and the lack of a default perspective. Speakers switched freely between FoRs and often combined multiple types in single descriptions. In contrast, a recall memory experiment conducted with 18 speakers revealed a strong bias toward responses consistent with the use of geocentric FoRs. It is argued that referential promiscuity makes FoR selection more task-specific, preventing the linguistic conditioning of spatial reference in internal cognition predicted for populations with more constrained linguistic usage.
Properties of learning of a fuzzy ART variant

This paper discusses a variation of the Fuzzy ART algorithm referred to as the Fuzzy ART Variant. The Fuzzy ART Variant is a Fuzzy ART algorithm that uses a very large choice parameter value. Based on the geometrical interpretation of the weights in Fuzzy ART, useful properties of learning associated with the Fuzzy ART Variant are presented and proven. One of these properties establishes an upper bound on the number of list presentations required by the Fuzzy ART Variant to learn an arbitrary list of input patterns. This bound is small and demonstrates the short-training time property of the Fuzzy ART Variant. Through simulation, it is shown that the Fuzzy ART Variant is as good a clustering algorithm as a Fuzzy ART algorithm that uses typical (i.e. small) values for the choice parameter.
Superconductivity and spin fluctuations in doped CeIr5

Abstract We report a detailed investigation of the binary compound CeIr5. Owing to difficulty in being able to prepare single-phase CeIr5, we studied the low-temperature properties of CeIr5, by investigating the doping-stabilized CeIr5, systems (Th1−xCex)Ir5, x ⩽ 0.7, and Ce(Pt1−xIrx)5, x ⩽ 0.85. Via measurements of the specific heat and magnetic susceptibility, we observed spin fluctuations in the Ce(Pt1−xIrx)5 system, arising from a Pauli paramagnetic state, and superconductivity in (Th1−xCex)Ir5.
A goal-oriented interface to consumer electronics using planning and commonsense reasoning

We are reaching a crisis with design of user interfaces for consumer electronics. Flashing 12:00 time indicators, push-and-hold buttons, and interminable modes and menus are all symptoms of trying to maintain a one-to-one correspondence between functions and physical controls, which becomes hopeless as the number of capabilities of devices grows. The root of this problem is that the devices do not have knowledge of (a) their own capabilities (b) the scenarios where they can be of use. By using commonsense knowledge and an AI partial-order planner we propose instead to orient interfaces around the goals that users have for the devices. We present Roadie, a user interface agent that provides intelligent context-sensitive help and assistance for a network of consumer devices. Roadie uses a commonsense knowledge base to map between user goals and functions of the devices, and an AI partial-order planner to provide mixed-initiative assistance with executing multi-step procedures and debugging help when things go wrong.
Bounds on Surface Stress-Driven Shear Flow

The background method is adapted to derive rigorous limits on surface speeds and bulk energy dissipation for shear stress-driven flow in two- and three-dimensional channels. By-products of the analysis are nonlinear energy stability results for plane Couette flow with a shear stress boundary condition: when the applied stress is gauged by a dimensionless Grashoff number $\operatorname{Gr}$ , the critical $\operatorname{Gr}$ for energy stability is 139.5 in two dimensions, and 51.73 in three dimensions. We derive upper bounds on the friction (a.k.a. dissipation) coefficient $C_{f} = \tau/\overline{u}^{2}$ , where τ is the applied shear stress and $\overline{u}$ is the mean velocity of the fluid at the surface, for flows at higher $\operatorname{Gr}$ including developed turbulence: C f ≤1/32 in two dimensions and C f ≤1/8 in three dimensions. This analysis rigorously justifies previously computed numerical estimates.
Type inference with partial types

This paper introduces a new form of type expressions which represent partial type information. These expressions are meant to capture the type information statically derivable from heterogeneous objects. The new monotypes form a lattice of subtypes and require type inference based on inclusion constraints. We discuss the existence and form of principle types under this extension and present a semi-decision procedure for the well-typing problem which can be restricted to a form that terminates for most practical programs. The partial type information derivable for heterogeneous entities is not sufficient to guarantee type-correctness for many of their uses. We therefore introduce a notion of statically generated dynamic type checks. Finally, all these elements are pulled together to sketch the derivation of a static system for "plausibility checking" which identifies the applications which may require a dynamic check and catches many type errors.
From solvolysis to self-assembly.

My sojourn from classical physical-organic chemistry and solvolysis to self-assembly and supramolecular chemistry, over the last forty years, is described. My contributions to unsaturated reactive intermediates, namely vinyl cations and unsaturated carbenes, along with my decade-long involvement with polyvalent iodine chemistry, especially alkynyliodonium salts, as well as my more recent research with metal−ligand, coordination driven, and directed self-assembly of finite supramolecular ensembles are discussed.
Resonant Relaxation in Protoplanetary Disks

Resonant relaxation is a novel form of gravitational relaxation that arises in nearly Keplerian disks such as protoplanetary disks. Resonant relaxation does not affect the semimajor axes of the particles but enhances relaxation of particle eccentricities and inclinations. The equilibrium state after resonant relaxation is a Rayleigh distribution, with the mean-square eccentricity and inclination inversely proportional to mass. The rate of resonant relaxation depends strongly on the precession rate of the disk. If the precession due to the disk's self-gravity is small compared to the total precession, then the relaxation is concentrated near the secular resonance between each pair of interacting bodies; on the other hand, if the precession rate is dominated by the disk's self-gravity, then relaxation occurs through coupling to the large-scale low-frequency m = 1 normal modes of the disk. Depending on the disk properties—especially the mean-square eccentricity—resonant relaxation may be either stronger or weaker than the usual nonresonant relaxation: for the terrestrial planets, nonresonant relaxation dominates in the early stages of planetesimal growth, but resonant relaxation may dominate in the late stages when the mean-square eccentricity is higher.
Energy management of three-dimensional minimum-time intercept

A real-time computer algorithm to control and optimize aircraft flight profiles is described and applied to a three-dimensional minimum-time intercept mission.
Selective Syntheses of Δα,β and Δβ,γ Butenolides from Allylic Cyclopropenecarboxylates via Tandem Ring Expansion/[3,3]-Sigmatropic Rearrangements

Allylic cyclopropenecarboxylates undergo ring expansion reactions to give 2-allyloxyfuran intermediates, which subsequently rearrange to Δβ,γ butenolides via a Claisen rearrangement or to the corresponding Δα,β butenolides via further Cope rearrangement. Also described are methods for chirality transfer in the rearrangement of nonracemic allylic esters.
Using Stochastically Generated Subcolumns to Represent Cloud Structure in a Large-Scale Model

A new method for representing subgrid-scale cloud structure in which each model column is decomposed into a set of subcolumns has been introduced into the Geophysical Fluid Dynamics Laboratory’s global atmospheric model AM2. Each subcolumn in the decomposition is homogeneous, but the ensemble reproduces the initial profiles of cloud properties including cloud fraction, internal variability (if any) in cloud condensate, and arbitrary overlap assumptions that describe vertical correlations. These subcolumns are used in radiation and diagnostic calculations and have allowed the introduction of more realistic overlap assumptions. This paper describes the impact of these new methods for representing cloud structure in instantaneous calculations and long-term integrations. Shortwave radiation computed using subcolumns and the random overlap assumption differs in the global annual average by more than 4Wm 2 from the operational radiation scheme in instantaneous calculations; much of this difference is counteracted by a change in the overlap assumption to one in which overlap varies continuously with the separation distance between layers. Internal variability in cloud condensate, diagnosed from the mean condensate amount and cloud fraction, has about the same effect on radiative fluxes as does the ad hoc tuning accounting for this effect in the operational radiation scheme. Long simulations with the new model configuration show little difference from the operational model configuration, while statistical tests indicate that the model does not respond systematically to the sampling noise introduced by the approximate radiative transfer techniques introduced to work with the subcolumns.
Effects of Piracy on Quality of Information Goods

It is commonly believed that piracy of information goods leads to lower profits, which translate to lower incentives to invest in innovation and eventually to lower-quality products. Manufacturers, policy makers, and researchers all claim that inadequate piracy enforcement efforts translate to lower investments in product development. However, we find many practical examples that contradict this claim. Therefore, to examine this claim more carefully, we develop a rigorous economic model of the manufacturer's quality decision problem in the presence of piracy. We consider a monopolist who does not have any marginal costs but has a product development cost quadratic in the quality level produced. The monopolist faces a consumer market heterogeneous in its preference for quality and offers a quality level that maximizes its profit. We also allow for the possibility that the manufacturer may use versioning to counter piracy. We unexpectedly find that in certain situations, lower piracy enforcement increases the monopolist's incentive to invest in quality. We explain the reasons and welfare implications of our findings. This paper was accepted by Lorin Hitt, information systems.
The Welfare State and Relative Poverty in Rich Western Democracies, 1967–1997

This study investigates the relationship between the welfare state and poverty with multiple measures of the welfare state and poverty in an unbalanced panel of 18 Western nations from 1967 to 1997. While addressing the limitations of past research, the analysis shows that social security transfers and public health spending significantly reduce poverty. Less robust evidence exists that social wages reduce poverty, while public employment and military spending do not significantly affect poverty. The welfare state's effects are far larger than economic and demographic sources of poverty. The significant features of the welfare state entirely account for any differences in poverty between welfare state regimes, and these features have similar effects across welfare state regimes. The welfare state's effects on poverty did not change in the 1990s. Sensitivity analyses show the results hold regardless of the U.S. cases. The welfare state emerges as the primary causal influence on national levels of poverty.
The economic value of the Earth's resources

Abstract Economics is the driving force of today's widespread environmental destruction. Markets undervalue the earth's resources and compound their overuse. Since World War II the world has used resources voraciously. The situation can be described as the industrial countries overconsuming resources, which are overextracted and exported by developing countries and traded at prices that are lower than the social costs. Resource-intensive patterns of growth and trade are Inefficient for the world economy, and lead to tragic maldistribution of the Earth's riches. They should be replaced by knowledge-intensive patterns of growth. Information technology and the environmental agenda are two of the most important trends in the world economy. Together they can lead to growth that is Intrinsically compatible with the environment.
A Terrestrial Search for Dark Contents of the Vacuum, Such as Dark Energy, Using Atom Interferometry

We describe the theory and first experimental work on our concept for searching on earth for the presence of dark contents of the vacuum (DCV) using atom interferometry. Specifically, we have in mind any DCV that has not yet been detected on a laboratory scale, but which might manifest itself as dark energy on the cosmological scale. The experimental method uses two atom interferometers to cancel the effect of earth's gravity and diverse noise sources. It depends upon two assumptions: first, that the DCV possesses some space inhomogeneity in density, and second that it exerts a sufficiently strong nongravitational force on matter. The motion of the apparatus through the DCV should then lead to an irregular variation in the detected matter-wave phase shift. We discuss the nature of this signal and note the problem of distinguishing it from instrumental noise. We also discuss the relation of our experiment to what might be learned by studying the noise in gravitational wave detectors such as LIGO. The paper concludes with a projection that a future search of this nature might be carried out using an atom interferometer in an orbiting satellite. The laboratory apparatus is now being constructed.
Mass savings domain of plasma propulsion for LEO to GEO transfer

A parametric model is used to study the mass savings of plasma propulsion over advanced chemical propulsion for lower-Earth-orbit to geosynchronous-Earth-orbit transfer. Such savings are characterized by stringent requirements of massive payloads [0(10) metric tons] and high-power levels [0(100) kW]. Mass savings on the order of the payload mass are possible but at the expense of longer transfer times (8-20 months). Typical of the savings domain is the case of a self-field magnetoplasmadynamic (MPD) thruster running quasisteadily, at an Is of 2000 s, with 600 kW of input power, raising a 50 metric ton satellite in 270 days. The initial mass at LEO will be 65 ton less than a 155 ton LOi/LHi advanced chemical high thrust spacecraft. An optimum Is can only be found if the cost savings associated with mass savings are counterbalanced by the cost losses incurred by longer transfer times. A simplistic cost model that illustrates the overall trends in the optimization yielded an optimum Is of about 2200 s for a cost effective baseline MPD system.
Determination of moment distributions and hyperfine fields at and surrounding transition-element solute atoms in Fe

A new method is developed which uses the hyperfine spectra of the Fe atoms in dilute Fe alloys to obtain (i) the moment on a transition-metal-solute atom in Fe, (ii) the moment perturbations in the Fe matrix, and (iii) the hyperfine-field shifts at the Fe atoms in the four-nearest-neighbor shells to the solute atom. We find that this method has much more sensitivitiy than the comparable technique using elastic diffuse neutron scattering. A moment perturbation varying as $\frac{1}{{r}^{3}}$ is found to best fit the spectra. For Co and Ni solute atoms we obtain moments of (1.9 \ifmmode\pm\else\textpm\fi{} 0.1)${\mathrm{\ensuremath{\mu}}}_{\mathit{B}}$ and (1.4 \ifmmode\pm\else\textpm\fi{} 0.1)${\mathrm{\ensuremath{\mu}}}_{\mathit{B}}$, respectively. These agree with the neutron-scattering results but are much more accurately determined. The moments at Rh and Pd in Fe are found to be (1.1 \ifmmode\pm\else\textpm\fi{} 0.2)${\mathrm{\ensuremath{\mu}}}_{\mathit{B}}$ and (0.7 \ifmmode\pm\else\textpm\fi{} 0.2)${\mathrm{\ensuremath{\mu}}}_{\mathit{B}}$, in agreement with neutron-scattering results on more concentrated alloys. The hyperfine-field shifts are obtained in a much more fundamental way than the previous analyses of FeCo spectra. This results in very different hyperfine-field shifts than the previous determination. The average-moment and moment-perturbation behavior is discussed from the point of view that the magnetic behavior of the $3d$ transition series is determined by the coupling via exchange and interband mixing of mainly localized moments through a small fraction of itinerant $d$ electrons. This is in contrast to a charge-perturbation-type model where the moment behavior is attributed to arise from the different screening of the spin-up and spin-down $d$ electrons. The latter is not believed to be significant in determining the moment behavior. Using the results of this analysis we derive from only hyperfine-field data the value of the core-polarization hyperfine field in Fe. We find indications that this term may be larger than the values previously obtained by band calculations. From the derived moments of Rh and Pd we can obtain a value for the hyperfine field per ${\mathrm{\ensuremath{\mu}}}_{\mathit{B}}$ due to core polarization for the $4d$ transition series. We find reasonable agreement with the calculated value. Earlier derivations of the moments of $4d$ and $5d$ solute atoms in Fe, as obtained from their measured hyperfine fields, omitted the large self-polarization conduction-electron term. This is considered here and corrected moment values are obtained.
A Principal Components Analysis of the Lick Indices of Galactic Globular Clusters

We present a principal components analysis (PCA) of high-quality Lick/IDS absorption-line measurements for 11 indices in the wavelength range 4100–5400 A for 39 Galactic globular clusters (GCs). Only the first principal component appears to be physically significant. We find that there is a tight linear relationship between this first component (PC1) and GC metallicity over a wide range in [m/H] (-1.8 ≤ [m/H] ≤ 0), suggesting that PC1 can be used to accurately estimate metallicities for old extragalactic GCs from their integrated spectra. (Metallicity calibrations for other sets of indices in this wavelength range can be furnished upon request.) The classic GC "second-parameter effect" is noticeable in the Balmer indices, although it does not appear in our PCA. We find little evidence for substantial differences in broad abundance patterns among Galactic GCs. One implication is that the metal-poor and metal-rich GC subpopulations formed from very similar physical processes.
Sulfo-click reaction via in situ generated thioacids and its application in kinetic target-guided synthesis

Herein, we describe a practical, one-pot variant of the sulfo-click reaction, in which 9-fluorenylmethyl-protected thioesters are rapidly deprotected and reacted further with sulfonylazides to give N-acyl sulfonamides.