cssi/SciSciGPT-SciSciNet huggingface dataset:
Distributed generation: An empirical analysis of primary motivators

What was once an industry dominated by centralized fossil-fuel power plants, the electricity industry in the United States is now evolving into a more decentralized and deregulated entity. While the future scope and scale of the industry is not yet apparent, recent trends indicate that distributed generation electricity applications may play an important role in this transformation. This paper examines which types of utilities are more likely to adopt distributed generation systems and, additionally, which factors motivate decisions of adoption and system capacity size. Results of a standard two-part model reveal that private utilities are significantly more inclined to adopt distributed generation than cooperatives and other types of public utilities. We also find evidence that interconnection standards and renewable portfolio standards effectively encourage consumer-owned distributed generation, while market forces associated with greater market competition encourage utility-owned distributed generation. Net metering programs are also found to have a significant marginal effect on distributed generation adoption and deployment.
Dynamic kinetic resolution via asymmetric conjugate reduction: enantio- and diastereoselective synthesis of 2,4-dialkyl cyclopentanones.

Herein, we report the kinetic and the dynamic kinetic resolutions of racemic 3,5-dialkyl-2-cyclopenten-1-ones. Kinetic resolution, with good selectivity factors (25−52), was achieved by conjugate reduction with catalytic CuCl/NaOt-Bu/(S)-p-tol-BINAP and stoichiometric quantities of poly(methylhydrosiloxane) (PMHS). When stoichiometric amounts of NaOt-Bu and t-BuOH were included in the reaction mixture, rapid racemization of the starting material occurred allowing for the dynamic kinetic resolution of the cyclopentenone substrates. In this process, chiral 2,4-dialkylcyclopentanones were isolated with high stereoselectivity (ee ≥ 91%, dr ≥ 90:10) and in high yield (≥89%).
Algorithmic theory of free solvable groups: Randomized computations

Abstract We design new deterministic and randomized algorithms for computational problems in free solvable groups. In particular, we prove that the word problem and the power problem can be solved in quasi-linear time and the conjugacy problem can be solved in quasi-quartic time by Monte Carlo type algorithms.
Cluster formation in contracting molecular clouds

We explore, through a simplified, semianalytic model, the formation of dense clusters containing massive stars. The parent cloud spawning the cluster is represented as an isothermal sphere. This sphere is in near-force balance between self-gravity and turbulent pressure. Self-gravity, mediated by turbulent dissipation, drives slow contraction of the cloud, eventually leading to a sharp central spike in density and the onset of dynamical instability. We suggest that, in a real cloud, this transition marks the late and rapid production of massive stars. We also offer an empirical prescription, akin to the Schmidt law, for low-mass star formation in our contracting cloud. Applying this prescription to the Orion Nebula Cluster, we are able to reproduce the accelerating star formation previously inferred from the distribution of member stars in the HR diagram. The cloud turns about 10% of its mass into low-mass stars before becoming dynamically unstable. Over a cloud free-fall time, this figure drops to 1%, consistent with the overall star formation efficiency of molecular clouds in the Galaxy.
Efficient solutions to the replicated log and dictionary problems

We propose efficient algorithms to maintain a replicated dictionary using a log in an unreliable network. A non-serializable approach is used to achieve high concurrency. The solutions are resilient to both node and communication failures. Optimizations are developed for networks which are not completely connected.
Activation of carbon fiber microelectrodes by alternating current electrochemical treatment

Abstract Carbon fiber microelectrodes subject to a simple ac electrochemical treatment exhibit substantial enhancement of the voltammetric response of numerous redox couples. The data suggest that the treatment removes contaminants from the surface, introduces surface functionalities, and increases the surface area. It appears that surface cleanliness plays an important role in observed activation. Pretreatment is characterized with respect to duration, potential limits, frequency, solution, analyte, residual current, long-term stability and other variables. Cyclic voltammetry, differential pulse voltammetry, and scanning electron microscopy are used to evaluate the redox and surface properties. The general applicability of the treatment is explored using more than twenty electroactive compounds of pharmaceutical and biological significance.
The Correlation Dimension of Young Stars in Dwarf Galaxies

We present the correlation dimension of resolved young stars in four actively star-forming dwarf galaxies that are sufficiently resolved and transparent to be modeled as projections of three-dimensional point distributions. We use data from the Hubble Space Telescope archive; photometry for one of the galaxies, UGCA 292, is presented here for the first time. We find that there are statistically distinguishable differences in the nature of stellar clustering among the sample galaxies. The young stars of VII Zw 403, the brightest galaxy in the sample, have the highest value for the correlation dimension and the most dramatic decrease with logarithmic scale, falling from 1.68 ± 0.14 to 0.10 ± 0.05 over less than a factor of 10 in r. This decrease is consistent with the edge effect produced by a projected Poisson distribution within a 2 : 2 : 1 ellipsoid. The young stars in UGC 4483, the faintest galaxy in the sample, exhibit very different behavior, with a constant value of about 0.5 over this same range in r, extending nearly to the edge of the distribution. This behavior may indicate either a scale-free distribution with an unusually low correlation dimension or a two-component (not scale-free) combination of cluster and field stars.
X1908+075: A Pulsar Orbiting in the Stellar Wind of a Massive Companion

We have observed the persistent but optically unidentified X-ray source X1908+075 with the Proportional Counter Array and High-Energy X-Ray Timing Experiment instruments on the Rossi X-Ray Timing Explorer (RXTE). The binary nature of this source was recently established by Wen et al., who found a 4.4 day orbital period in results from the RXTE All-Sky Monitor. We report the discovery of 605 s pulsations in the X-ray flux. The Doppler delay curve is measured and provides a mass function of 6.1 M☉, which is a lower limit to the mass of the binary companion of the neutron star. The degree of attenuation of the low-energy end of the spectrum is found to be a strong function of orbital phase. A simple model of absorption in a stellar wind from the companion star fits the orbital phase dependence reasonably well and limits the orbital inclination angle to the range 38°-72°. These measured parameters lead to an orbital separation of ~60-80 lt-s, a mass for the companion star in the range 9-31 M☉, and an upper limit to the size of the companion of ~22 R☉. From our analysis, we also infer a wind mass-loss rate from the companion star of 1.3 × 10-6 M☉ yr-1 and, when the properties of the companion star and the effects of photoionization are considered, likely 4 × 10-6 M☉ yr-1. Such a high rate is inconsistent with the allowed masses and radii that we find for a main-sequence or modestly evolved star unless the mass-loss rate is enhanced in the binary system relative to that of an isolated star. We discuss the possibility that the companion might be a Wolf-Rayet star that could evolve to become a black hole in 104 to 105 yr. If so, this would be the first identified progenitor of a neutron star-black hole binary.
Complex zeros of real ergodic eigenfunctions

We determine the limit distribution (as λ→∞) of complex zeros for holomorphic continuations φλ ℂ to Grauert tubes of real eigenfunctions of the Laplacian on a real analytic compact Riemannian manifold (M,g) with ergodic geodesic flow. If $\{\phi_{j_{k}}\}$ is an ergodic sequence of eigenfunctions, we prove the weak limit formula $\frac{1}{\lambda_j}[Z_{\phi_{j_k}}^{\mathbb{C}}]\ \to\ \frac{i}{\pi} \partial\bar{\partial} |\xi|_g$ , where $[Z_{\phi_{j_k}^{\mathbb{C}}}]$ is the current of integration over the complex zeros and where $\overline{\partial}$ is with respect to the adapted complex structure of Lempert-Szoke and Guillemin-Stenzel.
Stellar Rotation in Field and Cluster B Stars

We present the results of a spectroscopic investigation of 108 nearby field B stars. We derive their key stellar parameters, Vsin i, Teff, log g, and log gpolar, using the same methods that we used in our previous cluster B-star survey. By comparing the results of the field and the cluster samples, we find that the main reason for the overall slower rotation of the field sample is that it contains a larger fraction of older stars than found in the (mainly young) cluster sample.
Asymmetries between strange and antistrange particle production in pion–proton interactions

Recent measurements of the asymmetries between Feynman x-distributions of strange and antistrange hadrons in {pi}{sup -}A interactions show a strong effect as a function of x{sub F}. We calculate strange hadron production in the context of the intrinsic model and make predictions for particle/antiparticle asymmetries in these interactions.
Needlescopic surgery for cryptorchidism: The initial series*

Abstract Purpose: The aim of this study is to report the initial experience with needlescopic surgery (2-mm optics and instrumentation exclusively) for the cryptorchid testicle. Methods: Ten patients (age 8 months to 37 years) underwent 12 needlescopic procedures: orchiopexy (n = 8), orchiectomy (n = 2), and diagnostic exploration with attempted excision of testicular remnant (n = 2). Two patients underwent bilateral needlescopic orchiopexy. Needlescopic (2 mm) optics and instrumentation were used exclusively in the pediatric patients. Results: All procedures were completed successfully by needlescopic techniques. Mean surgical time was 110 minutes (range, 60 to 180 minutes), and blood loss was 6 mL (range, 0 to 20 mL). There were no intraoperative complications. All procedures were performed on an outpatient basis. In all 8 orchidopexies, the testis was successfully brought to a scrotal position. Conclusions: Needlescopic techniques allow safe performance of various procedures for a cryptorchid testicle. The cosmetic result is excellent. J Pediatr Surg 35:1426-1430. Copyright © 2000 by W.B. Saunders Company.
A new unwindowed lattice filter for RLS estimation

Adaptive lattice algorithms are derived for the solution of unwindowed least squares estimation problems for AR and FIR models. The basic approach is to embed the unwindowed problem in a larger prewindowed problem and then eliminate superfluous terms in the lattice. Initializations are given to allow the lattice to use no initial parameter estimates or to include initial parameter estimates with desired weightings in the quadratic criterion for parameter estimation. A numerical example is given. >
First dual-sweep streak camera measurements of a photoelectric injector drive laser☆

Abstract We have performed the first dual-sweep streak camera measurements of a photoelectric injector (PEI) drive laser in regard to micropulse duration, phase jitter, and phase slew. As the drive laser features are directly coupled to the eventual electron-beam properties, the characterization of these features is critical to optimizing free-electron laser (FEL) performance. The features have been investigated on both the intermacropulse and intramacropulse regimes at the Los Alamos FEL facility. In this initial phase we measured the doubled frequency component from the Nd:YLF-based laser system using a Hamamatsu C1587 universal streak camera with a synchroscan plug-in and the dual-sweep upgrade unit. We demonstrated that the macropulse-to-macropulse jitter was about 8 ps (rms) without laser phase stabilization and less than or equal to 2 ps (rms) with laser optimization and phase stabilization. Additionally, for the 100 μs long macropulse the phase slew within the macropulse was reduced with phase feedback from about 5 ps to near the resolution limit ( ps ).
Warped phenomenology of higher-derivative gravity

We examine the phenomenological implications at colliders for the existence of higher-derivative gravity terms as extensions to the Randall-Sundrum model. Such terms are expected to arise on rather general grounds, e.g., from string theory. In 5-d, if we demand that the theory be unitary and ghost free, these new contributions to the bulk action are uniquely of the Gauss-Bonnet form. We demonstrate that the usual expectations for the production cross section and detailed properties of graviton Kaluza-Klein resonances and TeV-scale black holes can be substantially altered by existence of these additional contributions. It is shown that measurements at future colliders will be highly sensitive to the presence of such terms.
Diplomatic and political problems affecting the formulation and implementation of an international protocol for activities following the detection of a signal from extraterrestrial intelligence

Abstract This paper is based on interviews with scientists and national space policy makers on what such a protocol should contain and their reactions to the draft of one proposed by the author at the 15th Review Meeting on the Search for Extraterrestrial Intelligence, held during the XXXVII International Astronautical Congress (1986). The key arguments against formulating a post-detection protocol are whether such advance work is necessary or practical, the implications it would have for national sovereignty and the wisdom of disseminating information about SETI research in general to the public. While such problems could be major obstacles to implementing a post-detection protocol, they are not sufficient grounds to discourage efforts to develop one. The principal operational problem will be to find an appropriate and effective international consultative body to which the discovery of extraterrestrial intelligence signals and plans for analyzing and responding to them can be referred. The paper recommends establishment of a new consultative organization which would be chartered under the auspices of the International Astronautical Union or other appropriate international scientific body.
A Dynamic Model of Competitive Entry Response

I develop a dynamic investment game with a “memoryless” research and development process in which an incumbent and an entrant can invest in a new technology, and the entrant can also invest in the old technology. I show that an increase in the probability of successfully implementing a technology can cause the incumbent to reduce its investment. Under certain conditions, if the success probability is high, the incumbent allows the entrant to win the new technology so that firms reach an equilibrium in which they use different technologies, and threats of retaliation prevent attacks; but if the success probability is low, such an equilibrium cannot be sustained, and both firms eventually implement both technologies.
Classifying bases for 6D F-theory models

We classify six-dimensional F-theory compactifications in terms of simple features of the divisor structure of the base surface of the elliptic fibration. This structure controls the minimal spectrum of the theory. We determine all irreducible configurations of divisors (“clusters”) that are required to carry nonabelian gauge group factors based on the intersections of the divisors with one another and with the canonical class of the base. All 6D F-theory models are built from combinations of these irreducible configurations. Physically, this geometric structure characterizes the gauge algebra and matter that can remain in a 6D theory after maximal Higgsing. These results suggest that all 6D supergravity theories realized in F-theory have a maximally Higgsed phase in which the gauge algebra is built out of summands of the types su(3), so(8), f4, e6, e8, e8, (g2 ⊕ su(2)); and su(2) ⊕ so(7) ⊕ su(2), with minimal matter content charged only under the last three types of summands, corresponding to the non-Higgsable cluster types identified through F-theory geometry. Although we have identified all such geometric clusters, we have not proven that there cannot be an obstruction to Higgsing to the minimal gauge and matter configuration for any possible F-theory model. We also identify bounds on the number of tensor fields allowed in a theory with any fixed gauge algebra; we use this to bound the size of the gauge group (or algebra) in a simple class of F-theory bases.
“Batch” Kinetics in Flow: Online IR Analysis and Continuous Control

Currently, kinetic data is either collected under steady-state conditions in flow or by generating time-series data in batch. Batch experiments are generally considered to be more suitable for the generation of kinetic data because of the ability to collect data from many time points in a single experiment. Now, a method that rapidly generates time-series reaction data from flow reactors by continuously manipulating the flow rate and reaction temperature has been developed. This approach makes use of inline IR analysis and an automated microreactor system, which allowed for rapid and tight control of the operating conditions. The conversion/residence time profiles at several temperatures were used to fit parameters to a kinetic model. This method requires significantly less time and a smaller amount of starting material compared to one-at-a-time flow experiments, and thus allows for the rapid generation of kinetic data.
1.8 TeV Tevatron upgrade lattices

The present Fermilab upgrade program calls for a future higher-energy (>or=1.5 TeV) superconducting accelerator to reside in the existing Tevatron tunnel. Three possible lattice designs for this accelerator are presented. The first involves longer straight sections which permit the extraction of 1.8-TeV beams to the fixed target experimental areas or external aborts. The second option uses stronger focusing quadrupoles to reduce the beam size throughout the accelerator. In this scheme, a large number of quadrupole circuits provide the necessary matching of the dispersion function across the long straight sections. The third option uses longer standard cells in the arcs, and the cell length is strategically chosen to minimize the dispersion wave generated by the medium- and mini-straight sections located in the arcs. The beam size is not as small as in the second option, though it is better behaved than in the present Tevatron lattice; in addition, it is believed that separator and low-beta schemes can be more easily implemented using this lattice design. >
General Analysis of Antideuteron Searches for Dark Matter

Lowenergycosmicrayantideuteronsprovideauniquelowbackgroundchannel for indirect detection of dark matter. We compute the cosmic ray flux of antideuterons from hadronic annihilations of dark matter for various Standard Model final states and determine the mass reach of two future experiments (AMS-02 and GAPS) designed to greatly increase the sensitivity of antideuteron detection over current bounds. We consider generic models of scalar, fermion, and massive vector bosons as thermal dark matter, describe their basic features relevant to direct and indirect detection, and discuss the implications of direct detection bounds on models of dark matter as a thermal relic. We also consider specific dark matter candidates and assess their potential for detection via antideuterons from their hadronic annihilation channels. Since the dark matter mass reach of the GAPS experiment can be well above 100GeV, we find that antideuterons can be a good indirect detection channel for a variety of thermal relic electroweak scale dark matter candidates, even when the rate for direct detection is highly suppressed.
Monopole track characteristics in plastic detectors

Total and restricted energy loss rates were calculated for magnetic monopoles of charge g = 137 e in Lexan polycarbonate. Range-energy curves are also presented. The restricted energy loss model is used to estimate the appearance of a monopole track in plastic detectors. These results should be useful for the design and analysis of monopole experiments.
Crossing the Brown Dwarf Desert Using Adaptive Optics: A Very Close L Dwarf Companion to the Nearby Solar Analog HR 7672

We have found a very faint companion to the active solar analog HR 7672 (HD 190406; GJ 779; 15 Sge). Three epochs of high-resolution imaging using adaptive optics (AO) at the Gemini-North and Keck II Telescopes demonstrate that HR 7672B is a common proper motion companion, with a separation of 079 (14 AU) and a 2.16 μm flux ratio of 8.6 mag. Using follow-up K-band spectroscopy from Keck AO+NIRSPEC, we measure a spectral type of L45 with an uncertainty of ±1.5 subclasses. This is the closest ultracool companion around a main-sequence star found to date by direct imaging. We estimate that the primary has an age of 1-3 Gyr. Assuming coevality, the companion is most likely substellar, with a mass of 55-78 MJ based on theoretical models. The primary star shows a long-term radial velocity trend, and we combine the radial velocity data and AO imaging to set a firm (model-independent) lower limit of 48 MJ. In contrast to the paucity of brown dwarf companions at 4 AU around FGK dwarfs, HR 7672B implies that brown dwarf companions do exist at separations comparable to those of the giant planets in our own solar system. Its presence is at variance with scenarios in which brown dwarfs form as ejected stellar embryos. Moreover, since HR 7672B is likely too massive to have formed in a circumstellar disk as planets are believed to, its discovery suggests that a diversity of physical processes act to populate the outer regions of exoplanetary systems.
Noncommutative Artin motives

In this article, we introduce the category of noncommutative Artin motives as well as the category of noncommutative mixed Artin motives. In the pure world, we start by proving that the classical category $${{\mathrm{AM}}}(k)_\mathbb Q $$ of Artin motives (over a base field k) can be characterized as the largest category inside Chow motives which fully embeds into noncommutative Chow motives. Making use of a refined bridge between pure motives and noncommutative pure motives, we then show that the image of this full embedding, which we call the category $${{\mathrm{NAM}}}(k)_\mathbb Q $$ of noncommutative Artin motives, is invariant under the different equivalence relations and modification of the symmetry isomorphism constraints. As an application, we recover the absolute Galois group $$\mathrm{Gal}(\overline{k}/k)$$ from the Tannakian formalism applied to $${{\mathrm{NAM}}}(k)_\mathbb Q $$ . Then, we develop the base-change formalism in the world of noncommutative pure motives. As an application, we obtain new tools for the study of motivic decompositions and Schur/Kimura finiteness. Making use of this theory of base-change, we then construct a short exact sequence relating $$\mathrm{Gal}(\overline{k}/k)$$ with the noncommutative motivic Galois groups of k and $$\overline{k}$$ . Finally, we describe a precise relationship between this short exact sequence and the one constructed by Deligne–Milne. In the mixed world, we introduce the triangulated category $${{\mathrm{NMAM}}}(k)_\mathbb Q $$ of noncommutative mixed Artin motives and construct a faithful functor from the classical category $${{\mathrm{MAM}}}(k)_\mathbb Q $$ of mixed Artin motives to it. When k is a finite field, this functor is an equivalence. On the other hand, when k is of characteristic zero $${{\mathrm{NMAM}}}(k)_\mathbb Q $$ is much richer than $${{\mathrm{MAM}}}(k)_\mathbb Q $$ since its higher Ext-groups encode all the (rationalized) higher algebraic $$K$$ -theory of finite etale k-schemes. In the appendix, we establish a general result about short exact sequences of Galois groups which is of independent interest. As an application, we obtain a new proof of Deligne–Milne’s short exact sequence.
Towards an abstract mathematical theory of floating-point arithmetic

The representation of integers by a place value sequence of digits taken from a radix polynomial is one of the profound mathematical developments of all times. It provides an elegant foundation for mathematical questions where algorithmic procedures are needed, such as how to computationally effect the operations of addition, subtraction, multiplication, division and comparison. Nevertheless, as invaluable as the place value representation system is to computational mathematics, most questions regarding the mathematical structure of the integers are usually answered with proofs which make no reference to any representational form of the integers, but are based solely on an abstract characterization of the integers.
Currency crises, sunspots and Markov-switching regimes

Abstract This paper investigates the theoretical properties of a class of escape clause models of currency crises as well as their applicability to empirical work. We show that under some conditions these models give rise to an arbitrarily large number of equilibria, as well as cyclic or chaotic dynamics for the devaluation expectations. We then propose an econometric technique, based on the Markov-switching regimes framework, by which these models can be brought to the data. We illustrate this empirical approach by studying the experience of the French franc between 1987 and 1993, and find that the model performs significantly better when it allows the devaluation expectations to be influenced by sunspots.
Total Synthesis of Vancomycin Aglycon-Part 2: Synthesis of Amino Acids 1-3 and Construction of the AB-COD-DOE Ring Skeleton.

A triazene-based synthetic strategy for the construction of the complex biaryl ethers and a Suzuki coupling reaction were the key steps in the synthesis of precursor 1 of the aglycon of vancomycin, which already contains the complete skeleton of the target compound. The cleavage of the triazene unit from the D ring and the removal of the other protecting groups led to the aglycon of vancomycin. These strategies should be particularly valuable for the synthesis of other naturally occurring glycopeptide antibiotics and offer opportunities for the synthesis of combinatorial libraries of compounds of the vancomycin family for chemical biology studies.
The Economic Effects of Bus Transit in Small Cities

This analysis investigates the impact of public transit in counties with small to medium-sized cities. The objectives are to answer: Do counties with bus transit have lower growth in transfer payme...
Redesigning the message logging model for high performance

Over the past decade the number of processors used in high performance computing has increased to hundreds of thousands. As a direct consequence, and while the computational power follows the trend, the mean time between failures (MTBF) has suffered and is now being counted in hours. In order to circumvent this limitation, a number of fault-tolerant algorithms as well as execution environments have been developed using the message passing paradigm. Among them, message logging has been proved to achieve a better overall performance when the MTBF is low, mainly due to a faster failure recovery. However, message logging suffers from a high overhead when no failure occurs. Therefore, in this paper we discuss a refinement of the message logging model intended to improve the failure-free message logging performance. The proposed approach simultaneously removes useless memory copies and reduces the number of logged events. We present the implementation of a pessimistic message logging protocol in Open MPI and compare it with the previous reference implementation MPICH-V2. The results outline a several order of magnitude improvement on the performance and a zero overhead for most messages. This article is a U.S. Government work and is in the public domain in the U.S.A.
A Parallel Iterative Improvement Stable Matching Algorithm

In this paper, we propose a new approach, parallel iterative improvement (PII), to solving the stable matching problem. This approach treats the stable matching problem as an optimization problem with all possible matchings forming its solution space. Since a stable matching always exists for any stable matching problem instance, finding a stable matching is equivalent to finding a matching with the minimum number (which is always zero) of unstable pairs. A particular PII algorithm is presented to show the effectiveness of this approach by constructing a new matching from an existing matching and using techniques such as randomization and greedy selection to speedup the convergence process. Simulation results show that the PII algorithm has better average performance compared with the classical stable matching algorithms and converges in n iterations with high probability. The proposed algorithm is also useful for some real-time applications with stringent time constraint.
Homogeneous iron complexes for the conversion of dinitrogen into ammonia and hydrazine

One of the most challenging problems in small molecule activation is the development of a homogeneous catalyst for converting dinitrogen into ammonia at ambient temperatures and atmospheric pressure. A catalytic cycle based on molybdenum that converts dinitrogen into ammonia has been reported. However, a well defined iron based system for the conversion of dinitrogen into ammonia or hydrazine has remained elusive, despite the relevance of iron to biological nitrogen fixation. In recent years several research groups have made significant progress towards this target. This tutorial review provides a brief historical perspective on attempts to develop iron based catalysts for dinitrogen functionalisation and then focuses on recent breakthroughs in the chemistry of coordinated dinitrogen, such as the generation of ammonia and hydrazine from coordinated dinitrogen, the isolation and characterisation of several proposed intermediates for ammonia generation and some preliminary mechanistic conclusions.
Centralized Institutions and Cascades

Why do sudden and massive social, economic, and political changes occur when and where they do? Are there institutional preconditions that encourage such changes when present and discourage such changes when absent? I employ a general model which suggests that cascades which induce massive equilibrium changes are more likely to occur in regimes with centralized coercive power, defined as the ability to impose more than one type of sanction (economic, legal, political, social, or religious). Centralized authorities are better able to suppress subversive actions when external shocks are small, as citizens have little incentive to incur numerous types of sanctions. However, citizens are also more likely to lie about their internal preferences in such regimes (e.g., falsely declare loyalty to an oppressive government), entailing that larger shocks are more likely to trigger a cascade to a vastly different equilibrium. The model is applied to the severity of protests that followed austerity measures taken in developing nations since the 1970s.
Fluidized Bed Experiments Using Platinum and Palladium Particles in Heavy Water

These experiments were designed to give the dynamic electrolysis conditions of fluidized beds by the use of small palladium particles. Both direct current electrolysis and pulse power electrolysis methods were used in this study. The excess power observed was 90 mW for direct current electrolysis in D2O + 0.1 M LiOD (I=0.300 to 0.400 A). For pulse electrolysis (pulse width 1.0 µs, pulse frequency 5 KHZ, peak voltage 98 V), the excess power increased to 250 mW. No excess power was observed for similar experiments using platinum particles in D2O + 0.1 M LiOD.
MULTIFLAVOR MASSIVE SCHWINGER MODEL WITH NON-ABELIAN BOSONIZATION

We revisit the treatment of the multiflavor massive Schwinger model by non-Abelian bosonization. We compare three different approximations to the low-lying spectrum: (i) reading it off from the bosonized Lagrangian (neglecting interactions), (ii) semiclassical quantization of the static soliton, (iii) approximate semiclassical quantization of the "breather" solitons. A number of new points are made in this process. We also suggest a different "effective low-energy Lagrangian" for the theory which permits easy calculation of the low-energy scattering amplitudes. It correlates an exact mass formula of the system with the requirement of the Mermin–Wagner theorem.
Change detection techniques for ERS-1 SAR data

Several techniques for detecting temporal changes in satellite synthetic-aperture radar (SAR) imagery are compared, using both theoretical predictions and spaceborne SAR data collected by the first European Remote Sensing Satellite, ERS-1. In a first set of techniques, changes are detected based on differences in the magnitude of the signal intensity between two dates. Ratioing of the multidate radar intensities is shown to be better adapted to the statistical characteristics of SAR data than subtracting, and works best when the number of looks is large. In a second set of techniques, changes are detected based on estimates of the temporal decorrelation of speckle. This method works best with one-look complex amplitude data, but can also be used with intensity data provided that the number of looks is small. The two techniques are compared using actual SAR data collected by ERS-1. The results illustrate the viability as well as the complementary character of these techniques for detecting changes in the structural and dielectric properties of remotely sensed surfaces. >
Aviation infrastructure performance and airline cost: a statistical cost estimation approach

Abstract The relationship between the performance of the US National Airspace System (NAS) and airline costs is examined by estimating airline cost functions that include NAS performance metrics as arguments, using quarterly data for 10 US domestic airlines. Performance metrics that vary by airline and quarter are developed by applying principal component analysis to seven underlying variables, including average delay, delay variance, and the proportion of flights that is cancelled. This analysis reveals that variation in the seven variables can be adequately captured by three or fewer factors, which we term NAS performance factors. If three factors are used, they can be interpretted as “delay”, “variability”, and “disruption”, the latter two of which are merged into a single “irregularity” factor in the two-factor model. Cost function estimation results confirm the anticipated link between NAS performance and airline cost. In the cost models with two and three performance factors, the irregularity and disruption factors are found to have the strongest cost impacts. These results challenge the prevailing assumption that delay reduction is the most important benefit from NAS enhancements. Using the estimated cost models, we predict airline cost savings from substantially improved NAS performance in the range $1–4 billion annually.
Active interlock for storage ring insertion devices

The insertion devices in the NSLS (National Synchrotron Light Source) X-ray ring produce such intense photon beams that passive measures alone are not adequate to protect the vacuum chamber. An active interlock is used to prevent thermal damage from improperly steered electron beams. The interlock system measures the position of the electron beam on both sides of the insertion devices using pickup electrodes and interrupts the RF if the beam moves outside a safe window. The interlock features redundant circuitry as well as an automatic testing procedure. >
Trust Primacy A Model of the Reciprocal Relations Between Trust and Perceived Justice

Management scholars have historically framed trust as a consequence of organizational justice that develops slowly over time. However, theory and empirical research outside of the management literature suggest that trust is inevitably present prior to the initiation of exchange relationships. For instance, neuroscientific evidence suggests that the human brain has evolved mechanisms capable of automatically evaluating the trustworthiness of potential exchange partners without conscious deliberation. This article presents a new theoretical model suggesting that trust forms rapidly and exerts significant influence on employee perceptions of justice. Implications for research and practice are discussed.
The use of temporal information in the regularization of the inverse problem of electrocardiography

The inverse problem of electrocardiography is solved in order to reconstruct electrical events within the heart from information measured noninvasively on the body surface. These electrical events can be deduced from measured epicardial potentials; therefore, a noninvasive method of recovering epicardial potentials from body surface data is useful in clinical and experimental work. The ill-posed nature of this problem necessitates the use of regularization in the solution procedure. Inversion using Tihonov zero-order regularization, a quasi-static method, had been employed previously and was able to reconstruct, with relatively good accuracy, important events in cardiac excitation (maxima, minima, etc.). Taking advantage of the fact that the process of cardiac excitation is continuous in time, one can incorporate information from the time progression of excitation in the regularization procedure using the Twomey technique. Methods of this type were tested on data obtained from a human-torso tank in which a beating canine heart was placed. The results show a marked improvement in the inverse solution when these temporal methods are used. >
Ultraviolet Absorption Spectrum of Chlorine Peroxide, ClOOCl

The photolysis of chlorine peroxide (ClOOCl) is understood to be a key step in the destruction of polar stratospheric ozone. This study generated and purified ClOOCl in a novel fashion, which resulted in spectra with low impurity levels and high peak absorbances. The ClOOCl was generated by laser photolysis of Cl2 in the presence of ozone, or by photolysis of ozone in the presence of CF2Cl2. The product ClOOCl was collected, along with small amounts of impurities, in a trap at about −125 °C. Gas-phase ultraviolet spectra were recorded using a long path cell and spectrograph/diode array detector as the trap was slowly warmed. The spectrum of ClOOCl could be fit with two Gaussian-like expressions, corresponding to two different electronic transitions, having similar energies but different widths. The energies and band strengths of these two transitions compare favorably with previous ab initio calculations. The cross sections of ClOOCl at wavelengths longer than 300 nm are significantly lower than all previ...
Draining our glass: an energy and heat characterization of Google Glass

The Google Glass is a mobile device designed to be worn as eyeglasses. This form factor enables new use cases, such as hands-free video chat and web search. However, its shape also hampers its potential: (1) battery size, and therefore lifetime, is limited by a need for the device to be lightweight, and (2) high-power processing leads to significant heat, which should be limited due to the compact form factor and proximity to the user's skin. We use an Explorer Edition of Glass (XE12) to study the power and thermal characteristics of optical head-mounted display devices. We share insights and implications to limit power draw to increase the safety and utility of head-mounted devices.
COUNTING LOW-MASS STARS IN INTEGRATED LIGHT

Low-mass stars (M {approx}< 0.4 M{sub Sun }) are thought to comprise the bulk of the stellar mass of galaxies but they constitute only of order 1 percent of the bolometric luminosity of an old stellar population. Directly estimating the number of low-mass stars from integrated flux measurements of old stellar systems is therefore possible but very challenging, given the numerous variables that can affect the light at the percent level. Here we present a new population synthesis model created specifically for the purpose of measuring the low-mass initial mass function (IMF) down to {approx}0.1 M{sub Sun} for metal-rich stellar populations with ages in the range 3-13.5 Gyr. Our fiducial model is based on the synthesis of three separate isochrones, and a combination of optical and near-IR empirical stellar libraries in order to produce integrated light spectra over the wavelength interval 0.35 {mu}m < {lambda} < 2.4 {mu}m at a resolving power of R Almost-Equal-To 2000. New synthetic stellar atmospheres and spectra have been computed in order to model the spectral variations due to changes in individual elemental abundances including C, N, Na, Mg, Si, Ca, Ti, Fe, and generic {alpha} elements. We demonstrate the power of combining blue spectralmore » features with surface gravity-sensitive near-IR features in order to simultaneously constrain the low-mass IMF, stellar population age, metallicity, and abundance pattern from integrated light measurements. Finally, we show that the shape of the low-mass IMF can also be directly constrained by employing a suite of surface gravity-sensitive spectral features, each of which is most sensitive to a particular mass interval.« less
Planarizing an Unknown Surface

It has been recently shown that any graph of genus g > 0 can be stochastically embedded into a distribution over planar graphs, with distortion O(log(g + 1)) [Sidiropoulos, FOCS 2010]. This embedding can be computed in polynomial time, provided that a drawing of the input graph into a genus-g surface is given.
Predicting consumer sentiments from online text

Sentiment analysis from unstructured text has witnessed a boom in interest in recent years, due to the sheer volume of online reviews and news corpora available in digital form. An accurate method for predicting sentiments could enable us, for instance, to extract opinions from the Internet and gauge online customers' preferences, which could prove valuable for economic or marketing research, for leveraging a strategic advantage for an enterprise, or for detecting cyber risk and security threats. In this paper, we propose a heuristic search-enhanced Markov blanket model that is able to capture the dependencies among words and provide a vocabulary that is adequate for the purpose of extracting sentiments. Computational results on two collections of online movie reviews and three collections of online news show that our method is able to identify a parsimonious set of predictive features, yet simultaneously yield comparable or better prediction results about sentiment orientations, than several state-of-the-art feature selection algorithms as well as sentiment prediction methods. Our results suggest that sentiments are captured by conditional dependencies among words as well as by keywords or high-frequency words.
Implementing network protocols at user level

Traditionally, network software has been structured in a monolithic fashion with all protocol stacks executing either within the kernel or in a single trusted user-level server. This organization is motivated by performance and security concerns. However, considerations of code maintenance, ease of debugging, customization, and the simultaneous existence of multiple protocols argue for separating the implementations into more manageable user-level libraries of protocols. This paper describes the design and implementation of transport protocols as user-level libraries.We begin by motivating the need for protocol implementations as user-level libraries and placing our approach in the context of previous work. We then describe our alternative to monolithic protocol organization, which has been implemented on Mach workstations connected not only to traditional Ethernet, but also to a more modern network, the DEC SRC ANI. Based on our experience, we discuss the implications for host-network interface design and for overall system structure to support efficient user-level implementations of network protocols.
Measuring two-event structural correlations on graphs

Real-life graphs usually have various kinds of events happening on them, e.g., product purchases in online social networks and intrusion alerts in computer networks. The occurrences of events on the same graph could be correlated, exhibiting either attraction or repulsion. Such structural correlations can reveal important relationships between different events. Unfortunately, correlation relationships on graph structures are not well studied and cannot be captured by traditional measures.In this work, we design a novel measure for assessing two-event structural correlations on graphs. Given the occurrences of two events, we choose uniformly a sample of "reference nodes" from the vicinity of all event nodes and employ the Kendall's τ rank correlation measure to compute the average concordance of event density changes. Significance can be efficiently assessed by τ's nice property of being asymptotically normal under the null hypothesis. In order to compute the measure in large scale networks, we develop a scalable framework using different sampling strategies. The complexity of these strategies is analyzed. Experiments on real graph datasets with both synthetic and real events demonstrate that the proposed framework is not only efficacious, but also efficient and scalable.
Evidence on the Economics of Equity Return Volatility Clustering

The underlying economic sources of volatility clustering in asset returns remain a puzzle in financial economics. Using daily equity returns, we study variation in the volatility relation between the conditional variance of individual firm returns and yesterday's market return shock. We find a number of regularities in this market-to-firm volatility relation. (1) It decreases following macroeconomic news announcements; (2) it does not change systematically during the high-news months when firms announce quarterly earnings; and (3) it increases substantially with our measures of dispersion-in-beliefs across traders about the market's common-factor signal. Our evidence suggests that volatility-clustering is a natural result of a price formation process with heterogeneous beliefs across traders, and that volatility clustering is not attributable to an autocorrelated news-generation process around public information such as macroeconomic news releases or firms' earnings releases. We find consistent results in our sample of large-capitalization firms in Japan and the U.K., which suggests a generality of our results and bolsters our economic interpretation.
Religion, Social Networks, and Life Satisfaction

Although the positive association between religiosity and life satisfaction is well documented, much theoretical and empirical controversy surrounds the question of how religion actually shapes life satisfaction. Using a new panel dataset, this study offers strong evidence for social and participatory mechanisms shaping religion’s impact on life satisfaction. Our findings suggest that religious people are more satisfied with their lives because they regularly attend religious services and build social networks in their congregations. The effect of within-congregation friendship is contingent, however, on the presence of a strong religious identity. We find little evidence that other private or subjective aspects of religiosity affect life satisfaction independent of attendance and congregational friendship.