cssi/SciSciGPT-SciSciNet huggingface dataset:
Endogenous Formation and Collapse Of Housing Bubbles

This paper develops an analytical framework and an agent-based spatial model of the housing market. We show that lenient nancing, in particular, low down payment requirement has caused business cycles in the housing market. With little down payment, any uctuations in the housing price will cause the collateral rate to fall below the threshold under which mortgage rate has to rise in response to a lower housing price. The agent-base model is based on our interviews with local real estate agents. The exploratory work in this paper will help us better understand the housing market, make policy advice, and prevent the damaging housing bubbles.
Vectorcardiographic Differentiation Between Right Ventricular Hypertrophy and Posterobasal Myocardial Infarction

Vectorcardiograms were recorded by the Frank lead system in 203 cases of right ventricular hypertrophy (RVH) and 85 cases of posterobasal myocardial infarction (PBMI). Of the RVH cases, 33 were confirmed by autopsy and 135 by cardiac catheterization or surgery. Of the cases of PBMI, 12 were confirmed by autopsy and 48 had definite clinical episodes associated with enzymatic or serial electrocardiographic changes or both. Of several measurements made, the following proved most helpful: (1) location of mean frontal plane QRS axis between 75° and 220° in 64% of the cases of RVH and between 350° and 74° in 78% of the cases of PBMI; (2) location of mean horizontal plane QRS axis between 350° and 90° in 85% of the cases of PBMI but in only 11% of the cases of RVH; (3) location of the 0.04-sec instantaneous vector in the horizontal plane between 350° and 60° in 76% of the cases of PBMI but in only 22% of the cases of RVH; (4) magnitude of terminal rightward voltage of less than 1.0 mv in 88% of the cases of PBMI...
Association of substance dependence phenotypes in the COGA sample

Alcohol and drug use disorders are individually heritable (50%). Twin studies indicate that alcohol and substance use disorders share common genetic influences, and therefore may represent a more heritable form of addiction and thus be more powerful for genetic studies. This study utilized data from 2322 subjects from 118 European-American families in the Collaborative Study on the Genetics of Alcoholism sample to conduct genome-wide association analysis of a binary and a continuous index of general substance dependence liability. The binary phenotype (ANYDEP) was based on meeting lifetime criteria for any DSM-IV dependence on alcohol, cannabis, cocaine or opioids. The quantitative trait (QUANTDEP) was constructed from factor analysis based on endorsement across the seven DSM-IV criteria for each of the four substances. Heritability was estimated to be 54% for ANYDEP and 86% for QUANTDEP. One single-nucleotide polymorphism (SNP), rs2952621 in the uncharacterized gene LOC151121 on chromosome 2, was associated with ANYDEP (P = 1.8 × 10(-8) ), with support from surrounding imputed SNPs and replication in an independent sample [Study of Addiction: Genetics and Environment (SAGE); P = 0.02]. One SNP, rs2567261 in ARHGAP28 (Rho GTPase-activating protein 28), was associated with QUANTDEP (P = 3.8 × 10(-8) ), and supported by imputed SNPs in the region, but did not replicate in an independent sample (SAGE; P = 0.29). The results of this study provide evidence that there are common variants that contribute to the risk for a general liability to substance dependence.
Time-Resolved Spectroscopy of Laser-Initiated Metal Combustion

A rapid-scan spectrometer employing a silicon-target vidicon detector was used to study the time-resolved emission spectra of laser-ignited metals. Bulk specimens of Ca, Mg, Zr, Ti and several Ti alloys were ignited with a 90 W cw CO2 laser in air or under a gentle flow of oxygen. Line and band emissions observed between 300 and 1100 nm during combustion help to identify vapor phase reactants and products and their locations in the flame. Disappearance of discrete spectra during the transient combustion of Ti and Zr gives information on the accumulation of molten oxide products. Observations of the continuum radiation emitted by laser-irradiated flames indicate a laser-stimulated luminescence from condensed metal oxide particles.
Patent Protection and Strategic Delays in Technology Development: Implications for Economic Growth

We present an endogenous growth model in which both the investment to develop a new technology—that upgrades the quality of machines—and entry of imitators are determined endogenously. According to the model, how soon the new-technology machine is launched after the patent is granted is influenced by two factors: returns to scale in technology development and "strategic delays." Strategic delays in technology development are most likely to occur when earlier dates of success enable imitators to enter an industry, that is, when imitation is swift and relatively cheap and/or patent protection is relatively lengthy. We then explore the link between the optimal patent length and economic growth and find that the equilibrium investment in technology development and thus the expected rate of technological progress exhibit an inverted U-shape relationship with respect to the legal patent length.
Inflation and the Redistribution of Nominal Wealth

This study quantitatively assesses the effects of inflation through changes in the value of nominal assets. It documents nominal asset positions in the United States across sectors and groups of households and estimates the wealth redistribution caused by a moderate inflation episode. The main losers from inflation are rich, old households, the major bondholders in the economy. The main winners are young, middle‐class households with fixed‐rate mortgage debt. Besides transferring resources from the old to the young, inflation is a boon for the government and a tax on foreigners. Lately, the amount of U.S. nominal assets held by foreigners has grown dramatically, increasing the potential for a large inflation‐induced wealth transfer from foreigners to domestic households.
Not ‘Like Sailors or Idiots or Infants’: Social Welfare Based Limits on Private Ordering in Business Association Law

Starting from the suggestion that external costs are created by the plenary private order regime — in short, that ‘private ordering’ is not truly private — the author advocates restrictions based on social welfare, and not traditional fairness, concerns when crafting limits on the extent to which participants in business firms can reorder their relations inter se from the statutorily defined relationship. A constructive start to this discussion would be to acknowledge that private ordering generates costs, some of which are social. Having done so, we could agree that an aggregate net social calculation of value and cost is appropriate to see if plenary private ordering is justified and, if not, to determine the appropriate level of private ordering. This policy discussion provides a valuable reminder of the value of commonality in these matters. Jurisdictions benefit when we adopt common modes of analysis, shared nomenclature and harmonisation statutes. That value of commonality has been too often put aside as we are guided by market-oriented generalisations which focus too heavily on the presumed benefits to individual participants and firms and ignore the social dimensions of public policy formation.
Brain-wide analysis of electrophysiological diversity yields novel categorization of mammalian neuron types

For decades, neurophysiologists have characterized the biophysical properties of a rich diversity of neuron types. However, identifying common features and computational roles shared across neuron ...
Infinite-message distributed source coding for two-terminal interactive computing

A two-terminal interactive function computation problem with alternating messages is studied within the framework of distributed block source coding theory. For any arbitrary fixed number of messages, a single-letter characterization of the minimum sum-rate function was provided in previous work using traditional information-theoretic techniques. This, however, does not directly lead to a satisfactory characterization of the infinite-message limit, which is a new, unexplored dimension for asymptotic-analysis in distributed block source coding involving potentially infinitesimal-rate messages. This paper introduces a new convex-geometric approach to provide a blocklength-free single-letter characterization of the infinite-message minimum sum-rate function as a functional of the joint source pmf. This characterization is not obtained by taking a limit as the number of messages goes to infinity. Instead, it is in terms of the least element of a family of partially-ordered marginal-perturbations-concave functionals associated with the functions to be computed. For computing the Boolean AND function of two independent Bernoulli sources at one and both terminals, the respective infinite-message minimum sum-rates are characterized in closed analytic form. These sum-rates are achievable using infinitely many infinitesimal-rate messages. The convex-geometric functional viewpoint also suggests an iterative algorithm for evaluating any finite-message minimum sum-rate function.
Mathematical Instantons in Characteristic Two

On P3, we show that mathematical instantons in characteristic two are unobstructed. We produce upper bounds for the dimension of the moduli space of stable rank two bundles on P3 in characteristic two. In cases where there is a phenomenon of good reduction modulo two, these give similar results in characteristic zero. We also give an example of a nonreduced component of the moduli space in characteristic two.
Parameterization of monoenergetic electron impact ionization

[1] We report a new parameterization of ionization in the Earth's atmosphere by isotropically precipitating monoenergetic (100 eV to 1 MeV) electrons. This new parameterization is the first one based on sophisticated first-principle models, and represents a significant improvement in accuracy, particularly for incident auroral and lower energies. Without previous need to interpolate over source energy and atmospheric range, the new parameterization provides an easier implementation with a robust fit of model calculations for a wide range of incident energies and atmospheric conditions. By decomposing any incident energy spectrum into contiguous monoenergetic components and then calculating and integrating their resulting ionization, our parameterization is a valuable tool that can be used in conjunction with global models to accurately quantify the impact from realistic precipitating electrons during space weather events.
The Possible Role of Proton-Coupled Electron Transfer (PCET) in Water Oxidation by Photosystem II

All higher life forms use oxygen and respiration as their primary energy source. The oxygen comes from water by solar-energy conversion in photosynthetic membranes. In green plants, light absorption in photosystem II (PSII) drives electron-transfer activation of the oxygen-evolving complex (OEC). The mechanism of water oxidation by the OEC has long been a subject of great interest to biologists and chemists. With the availability of new molecular-level protein structures from X-ray crystallography and EXAFS, as well as the accumulated results from numerous experiments and theoretical studies, it is possible to suggest how water may be oxidized at the OEC. An integrated sequence of light-driven reactions that exploit coupled electron-proton transfer (EPT) could be the key to water oxidation. When these reactions are combined with long-range proton transfer (by sequential local proton transfers), it may be possible to view the OEC as an intricate structure that is "wired for protons".
ALTERNATIVES TO CURRENT TRADE REMEDY LAW WITHIN NAFTA

Economists have long criticized anti-dumping and countervailing duty processes. Analysis of current AD and CVD processes indicates shortcomings compared to a system of dispute resolution. Potential changes to current practices should first consider which of many possible goals the changes are trying to achieve. Both tweaking the current system and introduction of new processes are explored. It is proposed that consultations and good offices, such as used in the dispute resolution system of the World Trade Organization, should be considered.
Mild and rapid Pd-catalyzed cross-coupling with hydrazine in continuous flow: application to the synthesis of functionalized heterocycles.

Continuous flow or batch reactions of the arylhydrazines, formed in the first step, with β-diketones, benzaldehyde and ketones allows the synthesis of pyrazoles, hydrazones, and indoles.
Closed Loop Terminal Guidance Navigation for a Kinetic Impactor Spacecraft

Abstract A kinetic impactor spacecraft is a viable method to deflect an asteroid which poses a threat to the Earth. The technology to perform such a deflection has been demonstrated by the Deep Impact (DI) mission, which successfully collided with comet Tempel 1 in July 2005 using an onboard autonomous navigation system, called AutoNav, for the terminal phase of the mission. In this paper, we evaluate the ability of AutoNav to impact a wider range of scenarios that a deflection mission could encounter, varying parameters such as the approach velocity, phase angle, size of the asteroid, and the attitude determination accuracy. In particular, we evaluated the capability of AutoNav to impact 100–300 m size asteroids at speeds between 7.5 and 20 km/s at various phase angles. Using realistic Monte Carlo simulations, we tabulated the probability of success of the deflection as a function of these parameters and find the highest sensitivity to be due to the spacecraft attitude determination error. In addition, we also specifically analyzed the impact probability for a proposed mission (called ISIS) which would send an impactor to the asteroid 1999RQ36. We conclude with some recommendations for future work.
Estimating the Difference Between Published and Unpublished Effect Sizes A Meta-Review

Practitioners and policymakers rely on meta-analyses to inform decision making around the allocation of resources to individuals and organizations. It is therefore paramount to consider the validity of these results. A well-documented threat to the validity of research synthesis results is the presence of publication bias, a phenomenon where studies with large and/or statistically significant effects, relative to studies with small or null effects, are more likely to be published. We investigated this phenomenon empirically by reviewing meta-analyses published in top-tier journals between 1986 and 2013 that quantified the difference between effect sizes from published and unpublished research. We reviewed 383 meta-analyses of which 81 had sufficient information to calculate an effect size. Results indicated that published studies yielded larger effect sizes than those from unpublished studies (d¯ = 0.18, 95% confidence interval [0.10, 0.25]). Moderator analyses revealed that the difference was larger in m...
Tissue-engineered skin substitutes.

The last two years have seen new tissue-engineered skin substitutes come onto the market and begin to resolve the various roles to which each is best suited. It is becoming evident that some of the very expensive cell-based products have cost-benefit advantage despite their high price and are valuable within the restricted applications for which they are intended. The use of skin substitutes for testing purposes has extended from epidermal keratinocytes to other integumentary epithelia and into preparations containing multiple cell types in which reactions resulting from paracrine interactions can be examined. Challenges remain in the application of gene therapy techniques to skin substitutes, both the control of transgene expression and in the selection of suitable genes to transfect. A coming challenge is the production of tissue-engineered products without the use of animal products other than human cells. A challenge that may be diminishing is the importance of acute rejection of allogeneic tissue-eng...
New horizons in planetary magnetospheres

Abstract The magnetospheres of Mercury, the Earth and Jupiter provide an especially good comparison of the processes that control the behavior of magnetospheres. The Mercurian magnetosphere is the smallest. Its field lines are anchored in the electrically conducting interior of Mercury and not in a conducting ionosphere. The Earth’s magnetosphere is over an order of magnitude larger than Mercury’s and its ionosphere is dynamically important. Also significant are that synchronous orbit occurs relatively far out in the magnetosphere and that the solar wind is responsible for the energization of processes therein. Jupiter’s magnetosphere is another two orders of magnitude larger. Its synchronous orbit, where gravity and centrifugal force balance, lies deep inside the magnetosphere, about 2% of the way to the magnetopause. Most importantly the jovian magnetosphere has a strong source of ions deep in the magnetosphere, but well outside of synchronous orbit, that are accelerated to high velocities. The energy of these accelerated ions and their centrifugal force are sufficient to drastically alter the behavior of the jovian magnetosphere so that it behaves much differently than the terrestrial magnetosphere. In this review, we examine what we know about each of these magnetospheres in the areas in which their contrasts reveal the underlying controlling factors of magnetospheric behavior.
Firm and Guarantor Risk, Risk Contagion, and the Interfirm Spread among Insured Deposits

We develop a model of third party guaranteed debt and show that interest rate premiums are multiplicatively related to firm and guarantor risk. We apply the model to thrifts issuing CDs guaranteed by the FSLIC and then estimate firm probabilities of insolvency and guarantor risk across 20 observed months. This time period spans the insolvency of the guarantor followed by two recapitalizations. The relative stability in firm risk across time offers no evidence of generalized risk contagion among firms. We attribute elevated CD premiums and rate spreads to increases in guarantor risk rather than changes in firm risk. On third party guaranteed debt, the risk of both the issuing firm and guarantor determines the interest rate. We show that the interest premium above the riskless Treasury rate for guaranteed debt is multiplicatively related to two factors: the probability of firm insolvency, and the expected cost of an incomplete guarantor payoff. We demonstrate that the presence of the guarantor obscures firm risk. Despite this, our model provides the basis for measuring firm risk as well as guarantor risk. We explain how different rates can exist on different firms' debt with the same guarantor and how spreads among the different firms' rates widen when the guarantor becomes riskier. Only a riskless guarantor causes the spreads to disappear. Our model fits nicely the case where savings and loans issue certificates of deposit (CDs) and the guarantor is the government's deposit insuring agency, the Federal Savings and Loan Insurance Corporation (FSLIC). In this case, the debt instrument, the guarantor, and the guarantee are the same for all the firms. We apply the model over a 20-month period beginning in January 1987 when, fol? lowing hundreds of thrift failures, the FSLIC announced its own insolvency. The
Examining the Evolving Correspondence Between Petroleum Prices and Agricultural Commodity Prices

Over the last few years, the production of renewable fuels has increased dramatically. Rising oil prices, limited supplies of fossil fuel, and increased concerns about global warming have created a growing demand for renewable energy sources. Both the ethanol and biodiesel industries have experienced tremendous growth in the past few years. The production of these fuels is highly dependent on the availability of agricultural feedstocks. This research examined the covariability between crude oil prices and corn, sorghum, sugar, soybeans, soybean oil, and palm oil prices during the 2003-2007 time period. Johansen cointegration tests revealed no cointegrating relationships during the 2003-2005 time frame. However, corn prices and soybean prices were cointegrated with crude oil prices during the 2006-2007 time period.
Doctoral Training in Clinical Psychology

Competing models of doctoral training in clinical psychology are described and compared within their historical contexts. Trends in the field are examined critically with a focus on the impact of managed care on doctoral training and clinical practice. Implications for the future of doctoral training are considered, and a blueprint for the future of doctoral training in clinical psychology is presented.
Pressureless sintering of Si3N4 ceramic using AlN and rare-earth oxides

Using intermediate, liquid-forming compositions in the (Y,La)2O3-AlN system as additives, fully dense Si3N4 ceramics with high strength at high temperature have been obtained by pressureless sintering. The ceramics contain rod-shaped β-Si3N4 with M′ or K′ solid solutions as grain-boundary phases. The strength of these ceramics is 1150 MPa at 1200°C, and the room-temperature toughness is maintained at }7 MPa·m1/2. Phase relations that are pertinent to the new additive compositions are delineated to rationalize their beneficial effects on sinterability and mechanical properties.
The Time-Varying Volatility of Macroeconomic Fluctuations

We investigate the sources of the important shifts in the volatility of US mac - roeconomic variables in the postwar period. To this end, we propose the esti - mation of DSGE models allowing for time variation in the volatility of the structural innovations. We apply our estimation strategy to a large-scale model of the business cycle and find that shocks specific to the equilibrium condition of investment account for most of the sharp decline in volatility of the last two decades. (JEL C51, E32)
Update with out-of-sequence measurements in tracking: exact solution

In target tracking systems measurements are typically collected in "scans" or "frames" and then they are transmitted to a processing center. In multisensor tracking systems that operate in a centralized manner, there are usually different time delays in transmitting the scans or frames from the various sensors to the center. This can lead to situations where measurements from the same target arrive out of sequence. Such "out-of-sequence" measurement (OOSM) arrivals can occur even in the absence of scan/frame communication time delays. The resulting "negative-time measurement update" problem, which is quite common in real multisensor systems, was solved previously only approximately in the literature. The exact state update equation for such a problem is presented. The optimal and two suboptimal algorithms are compared on a number of realistic examples, including a GMTI (ground moving target indicator) radar case.
The ARRA investment in CER: a description of the midstream evaluation and how the funds were allocated and CER priorities addressed

Aim: To describe the evaluation design of the American Recovery and Reinvestment Act of 2009 comparative effectiveness research (CER) investment, how funds were allocated and how CER priorities were addressed. Materials & methods: Primary and secondary data included information from redacted project proposals, an investigator survey and federal project officers, investigators and expert panel discussions. Results: More than 420 projects (US$1.1 billion) were awarded. Those generating new or synthesizing existing CER made up the plurality (194, or US$524 million). Data infrastructure projects were the second-largest area (28%, US$302 million). More than three-fourths addressed at least one priority population, condition category or intervention category. Conclusion: These investments expanded the nation's CER activities and its future capacity to conduct CER.
The Statistical Mechanics of Complex Product Development: Empirical and Analytical Results

In recent years, understanding the structure and function of complex networks has become the foundation for explaining many different real-world complex biological, technological, and informal social phenomena. Techniques from statistical physics have been successfully applied to the analysis of these networks, and have uncovered surprising statistical structural properties that have also been shown to have a major effect on their functionality, dynamics, robustness, and fragility. This paper examines, for the first time, the statistical properties of strategically important organizational networks---networks of people engaged in distributed product development (PD)---and discusses the significance of these properties in providing insight into ways of improving the strategic and operational decision making of the organization. We show that the structure of information flow networks that are at the heart of large-scale product development efforts have properties that are similar to those displayed by other social, biological, and technological networks. In this context, we also identify novel properties that may be characteristic of other information-carrying networks. We further present a detailed model and analysis of PD dynamics on complex networks, and show how the underlying network topologies provide direct information about the characteristics of these dynamics. We believe that our new analysis methodology and empirical results are also relevant to other organizational information-carrying networks.
Diet in early Homo : A review of the evidence and a new model of adaptive versatility

AbstractSeveral recent studies have stressed the role of dietary change in the origin and early evolution of our genus in Africa. Resulting models have been based on nutrition research and analogy to living peoples and nonhuman primates or on archeological and paleoenvironmental evidence. Here we evaluate these models in the context of the hominin fossil record. Inference of diet from fossils is hampered by small samples, unclear form-function relationships, taphonomic factors, and interactions between cultural and natural selection. Nevertheless, craniodental remains of Homo habilis, H. rudolfensis, and H. erectus offer some clues. For example, there appears to be no simple transition from an australopith to a Homo grade of dietary adaptation, or from closed forest plant diets to reliance on more open-country plants or animals. Early Homo species more likely had adaptations for flexible, versatile subsistence strategies that would have served them well in the variable paleoenvironments of the African Pli...
Optimal buffer control during congestion in an ATM network node

Study the problem of optimal buffer space priority control in an ATM network node. The buffer of a transmission link is shared among the cells of several traffic classes waiting for transmission through the link. When the number of cells to be stored in the buffer exceeds the available buffer space, certain cells have to be dropped. Different traffic classes have different sensitivities to cell losses. By appropriately selecting the classes of cells which are dropped or blocked in case of overflow, one can have the more sensitive classes suffering smaller cell losses. Depending on the control that on the system, three classes of policies are distinguished. In each one, policies that schedule the buffer allocation in some optimal manner are identified. >
Isolation and Identification of Vitamin C

The previous work reported from this laboratory (l-5) on the chemical nature of vitamin C has been continued, particularly in the study of the solubility of the active material in organic solvents, leading towards its isolation by crystallization. This paper deals with (a) the precipitation of the active material as the lead salt, and (b) the isolation of a crystalline compound which is active in preventing scurvy in guinea pigs. The properties of this active crystalline substance correspond with those given for the LLhexuronic acid” studied by Szent-Gyorgyi (6-7) as an oxidation-reduction factor in adrenal cortex, oranges, and cabbage. We believe that the two subst.ances are identical, as stated in a previous communication (8).
The Leyton Obsessional Inventory-Child Version

The Leyton Obsessional Inventory for adults was modified for children and administered to 26 adolescents ( age 14.3 ± 2.1 years) meeting DSM-III criteria for obsessive compulsive disorder, 14 adolescents ( age 13.7 ± 1.7 years) having severe obsessive symptoms but who had received other primary psychiatric diagnoses, and 28 normal adolescent controls ( age 13.7 ± 1.9 years). The Leyton Obsessional Inventory-Child Version (LOI-CV) significantly differentiated obsessive patients from normal controls on total scores for obsessional symptoms as well as total scores for degree of resistance to the symptoms and interference with everyday life. Patients and psychiatric controls differed significantly on scores for resistance and interference. Test-retest reliability for patients was demonstrated and scores differentiating placebo and active drug treatment indicated further clinical validity. However, LOI-CV scores did not correlate significantly with other clinical measures of obsessive behavior (Obsessive Compulsive Rating Scale, Comprehensive Psychopathological Rating Scale, NIMH Global and Obsessive Compulsive Scales) obtained at baseline.
The Great Compression: The Wage Structure in the United States at Mid-Century

The era of wage stretching has been a current focus, but we direct attention here to a decade of extraordinary wage compression—the 1940s. Wages narrowed by education, job experience, and occupation, and compression occurred within cells. The 90–10 differential in the log of wages for men was 1.45 in 1940 but 1.06 in 1950. By the late 1980s it returned to its 1940 level, thus restoring a dispersion of 50 years ago. World War II and the National War Labor Board share some credit for the Great Compression, but much was due to an increased demand for unskilled labor when educated labor was greatly expanding.
Stability and transparency in bilateral teleoperation

Tools for quantifying teleoperation system performance and stability when communication delays are present are provided. A general multivariable system architecture is utilized which includes all four-types of data transmission between master and slave: force and velocity in both directions. It is shown that a proper use of an four channels is of critical importance in achieving high performance telepresence in the sense of accurate transmission of task impedances to the operator. It is also shown that transparency and robust stability (passivity) are conflicting design goals in teleoperation systems. The analysis is illustrated by comparing transparency and stability in two common architectures, as well as a recent passivated approach and a new transparency-optimized architecture, using simplified one-degree-of-freedom examples. >
Random walks on the torus with several generators

Given n vectors {α→i}ni=1 ∈ [0, 1)d, consider a random walk on the d-dimensional torus Td =Rd/Zd generated by these vectors by successive addition and subtraction. For certain sets of vectors, this walk converges to Haar (uniform) measure on the torus. We show that the discrepancy distance D(Q*k) between the kth step distribution of the walk and Haar measure is bounded below by D(Q*k) ≥ C1k-n/2, where C1 = C(n, d) is a constant. If the vectors are badly approximated by rationals (in a sense we will define), then D(Q*k) ≤ C2k-n/2d for C2 = C(n, d, α→j) a constant.
Vibrational Lifetimes of Hydrogen in Silicon: Isotope Effects and MOSFET Reliability

Characterization of defect and impurity reactions, dissociation and migration in semiconductors requires detailed understanding of rates and pathways of vibrational energy flow, of energy transfer channels and of coupling mechanisms between local modes and the phonon bath of the host material. Significant progress in reaching this goal has been accomplished in recent landmark studies exploring the excitation and dynamics of vibrational states associated with hydrogen in silicon. We describe recent experiments which measure the vibrational lifetime of the Si-H bond in various defect configurations and show the relationship between these lifetimes and silicon MOSFET reliability.
Observable and hidden singular features of large fluctuations in nonequilibrium systems

We study local features, and provide a topological insight into the global structure of the probability density distribution and of the pattern of the optimal paths for large rare fluctuations away from a stable state. In contrast to extremal paths in quantum mechanics, the optimal paths do not encounter caustics. We show how this occurs, and what, instead of caustics, are the experimentally observable singularities of the pattern. We reveal the possibility for a caustic and a switching line to start at a saddle point, and discuss the consequences.
How stochastic is the relative bias between galaxy types

Examining the nature of the relative clustering of different galaxy types can help tell us how galaxies formed. To measure this relative clustering, I perform a joint counts-in-cells analysis of galaxies of different spectral types in the Las Campanas Redshift Survey (LCRS). I develop a maximum-likelihood technique to fit for the relationship between the density fields of early- and late-type galaxies. This technique can directly measure nonlinearity and stochasticity in the biasing relation. At high significance, a small amount of stochasticity is measured, corresponding to a correlation coefficient r ≈ 0.87 on scales corresponding to 15 h-1 Mpc spheres. A large proportion of this signal appears to derive from errors in the selection function, and a more realistic estimate finds r ≈ 0.95. These selection function errors probably account for the large stochasticity measured by Tegmark & Bromley, and may have affected measurements of very large-scale structure in the LCRS. Analysis of the data and of mock catalogs shows that the peculiar geometry, variable flux limits, and central surface brightness selection effects of the LCRS do not seem to cause the effect.
Creating Simple and Effective Prerecorded Web-Based Lectures

Recent advances in computer hardware and software can enable individual instructors to easily create and deliver prerecorded lectures via the World Wide Web. Using new video and audio compression techniques, an entire semester of lectures can be stored on less than 2 gigabytes of disk space and delivered over the Internet on demand. A methodology for quickly generating effective lectures at relatively low video frame rates is described, and examples of the technique are provided on the Web.
Scattering of color dipoles: from low to high energies

A dipole-dipole scattering amplitude is calculated exactly in the first two orders of perturbation theory. This amplitude is an analytic function of the relative energy and the dipoles' sizes. The cross section of the dipole-dipole scattering approached the high-energy BFKL asymptotics starting from relatively large rapidity {approx}4.
Experimenting in mobile social contexts using JellyNets

Programmable consumer devices have placed computation within arm's reach at all times and in all places. Unfortunately, researchers interested in investigating this phenomenon often struggle with the expense, inconvenience, and limited scale of existing experimental platforms. In this paper, we introduce a new experimental platform for mobile and pervasive computing based on JellyNets, an abstraction for exposing experiments to arbitrary mobile social contexts.
Lower Bounds for Multi-Player Pointer Jumping

We consider the k-layer pointer jumping problem in the one-way multi-party number-on-the-forehead communication model. Sufficiently strong lower bounds for the problem would have major consequences in circuit complexity. We take an information complexity approach to this problem and obtain three lower bounds that improve upon earlier work. For myopic protocols (where players may see only one layer ahead but arbitrarily far behind), we greatly improve a lower bound due to Gronemeier (2006). Our new lower bound is Omega(n/k), where n is the number of vertices per layer. For conservative protocols (where players may see arbitrarily far ahead but not behind, instead seeing only the vertex reached by following the pointers up to their layer), we extend an Omega(n/k2) lower bound due to Damm, Jukna and Sgall (1998) so that it applies for all k. The above two bounds apply even to the Boolean version of pointer jumping. Our third lower bound is for the non-Boolean case and for k les log* n. We obtain an Omega(n log(k-1) n) bound for myopic protocols. Damm et al. had obtained a similar bound for deterministic conservative protocols. All our lower bounds apply directly to randomised protocols.
Synthesis of Hexacelsian Barium Aluminosilicate by a Solid‐State Process

Synthesis of hexacelsian barium aluminosilicate (BaAl2Si2O8 or BAS) from BaCO3, Al2O3, and amorphous SiO2 was examined. BaCO3 can react with SiO2 and Al2O3 to form barium silicates (Ba2SiO4 or B2S, BaSiO3 or BS, and BaSi2O5 or BS2) and barium aluminate (BaAl2O4 or BA). It is shown that there are two competitive reactions leading to the formation of hexacelsian BAS. One involves a reaction between BS2 and Al2O3 and the other involves a reaction between BA and SiO2. In experiments with the model BS2–Al2O3 and BA–SiO2 systems it is shown that the reaction between BS2 and Al2O3 is much faster than the reaction between BA and SiO2. However, in the BAS system, Al2O3 suppresses the reactions which form BS2 and instead reacts with B2S and BS to form BA. The kinetics of hexacelsian BAS formation are greatly enhanced when BS2 is made separately and fired with Al2O3 to yield BAS.
Throwing Darts: Random Sampling Helps Tree Search when the Number of Short Certificates Is Moderate

One typically proves infeasibility in satisfiability/constraint satisfaction (or optimality in integer programming) by constructing a tree certificate. However, deciding how to branch in the search tree is hard, and impacts search time drastically. We explore the power of a simple paradigm, that of throwing random darts into the assignment space and then using information gathered by that dart to guide what to do next. Such guidance is easy to incorporate into state-of-the-art solvers. This method seems to work well when the number of short certificates of infeasibility is moderate, suggesting the overhead of throwing darts can be countered by the information gained by these darts. We explore results supporting this suggestion both on instances from a new generator where the size and number of short certificates can be controlled, and on industral instances from the annual SAT competition.
Management of Birth Injuries

Birth injuries are a significant cause of neonatal morbidity and mortality. Although often associated with traumatic delivery, birth injuries often occur in normal spontaneous deliveries in the absence of any risk factors. This article discusses the diagnosis and management of the most common birth injuries that are encountered by health care providers who care for newborns.
Colligative Properties of Solutions: I. Fixed Concentrations

Using the formalism of rigorous statistical mechanics, we study the phenomena of phase separation and freezing-point depression upon freezing of solutions. Specifically, we devise an Ising-based model of a solvent--solute system and show that, in the ensemble with a fixed amount of solute, a macroscopic phase separation occurs in an interval of values of the chemical potential of the solvent. The boundaries of the phase separation domain in the phase diagram are characterized and shown to asymptotically agree with the formulas used in heuristic analyses of freezing-point depression. The limit of infinitesimal concentrations is described in a subsequent paper.
Bulk spectral function sum rule in QCD-like theories with a holographic dual

We derive the sum rule for the spectral function of the stress-energy tensor in the bulk (uniform dilatation) channel in a general class of strongly coupled field theories. This class includes theories holographically dual to a theory of gravity coupled to a single scalar field, representing the operator of the scale anomaly. In the limit when the operator becomes marginal, the sum rule coincides with that in QCD. Using the holographic model, we verify explicitly the cancellation between large and small frequency contributions to the spectral integral required to satisfy the sum rule in such QCD-like theories.
Rectangular mixed elements for elasticity with weakly imposed symmetry condition

We present new rectangular mixed finite elements for linear elasticity. The approach is based on a modification of the Hellinger---Reissner functional in which the symmetry of the stress field is enforced weakly through the introduction of a Lagrange multiplier. The elements are analogues of the lowest order elements described in Arnold et al. (Math Comput 76:1699---1723, 2007). Piecewise constants are used to approximate the displacement and the rotation. The first order BDM elements are used to approximate each row of the stress field.
Asynchronous Interactive Control Systems

A class of interactive control systems is derived by generalizing interactive manipulator control systems. The general structural properties of such systems are discussed and an appropriate general software implementation is proposed. This is based on the fact that tasks of interactive control systems can be represented as a network of a finite set of actions which have specific operational characteristics and specific resource requirements, and which are of limited duration. This has enabled the decomposition of the overall control algorithm into a set of subalgorithms, called subcontrollers, which can operate simultaneously and asynchronously. Coordinate transformations of sensor feedback data and actuator set-points have enabled the further simplification of the subcontrollers and have reduced their conflicting resource requirements. The modules of the decomposed control system are implemented as parallel processes with disjoint memory space communicating only by I/O. The synchronization mechanisms for dynamic resource allocation among subcontrollers and other synchronization mechanisms are also discussed in this paper. Such a software organization is suitable for the general form of multiprocessing using computer networks with distributed storage.
Singular perturbation analysis of free-time optimal control problems

Abstract The singular perturbation theory for free-time optimal control problems is developed, introducing a scaling parameter as an additional parameter, and then extended to eontrol-mequality constraints.
High-order shock capturing schemes for turbulence calculations

This work investigates high-order central compact methods for simulating turbulent supersonic flows that include shock waves. Several different types of previously proposed characteristic filters, including total variation diminishing, monotone upstream-centered scheme for conservation laws, and weighted essentially non-oscillatory filters, are investigated in this study. Similar to the traditional shock capturing schemes, these filters can eliminate the numerical instability caused by large gradients in flow fields, but they also improve efficiency compared with classical shock-capturing schemes. Adding the nonlinear dissipation part of a classical shock-capturing scheme to a central scheme makes the method suitable for incorporation into any existing central-based high-order subsonic code. The amount of numerical dissipation to add is sensed by means of the artificial compression method switch. In order to improve the performance of the characteristic filters, we propose a hybrid approach to minimize the dissipation added by the characteristic filter. Through several numerical experiments (including a shock/density wave interaction, a shock/vortex interaction, and a shock/mixing layer interaction) we show that our hybrid approach works better than the original method, and can be used for future turbulent flow simulations that include shocks. Copyright © 2009 John Wiley & Sons, Ltd.
To Commit or Not to Commit: Revisiting Quantity vs. Price Competition in a Differentiated Industry

Previous studies have shown that quantity commitment by all firms in an industry mitigates price competition. This paper shows that when firms have a choice, asymmetric outcomes can arise, with some firms choosing to commit to a quantity and other firms choosing not to. To study the commitment decision, we analyze a multistage game within a duopoly of differentiated firms a la Hotelling. In the first stage of the game, firms choose whether or not to commit to a quantity. In the second stage, each firm that chose to commit sets a quantity, which represents an upper bound on how much it can sell to consumers. In the third stage, both firms set prices strategically, regardless of whether or not they committed. In the final stage, demand is allocated as consumers maximize their utilities. Firm(s) that chose not to commit to a quantity in the first stage can fulfill any quantity that consumers demand at the equilibrium prices. We find that if product differentiation is sufficiently low, both firms choose to co...
GT-PML: generalized theory of perfectly matched layers and its application to the reflectionless truncation of finite-difference time-domain grids

A new mathematical formulation is presented for the systematic development of perfectly matched layers from Maxwell's equations in properly constructed anisotropic media. The proposed formulation has an important advantage over the original Berenger's perfectly matched layer in that it can be implemented in the time domain without any splitting of the fields. The details of the numerical implementation of the proposed perfectly matched absorbers in the context of the finite-difference time-domain approximation of Maxwell's equations are given. Results from three-dimension (3-D) simulations are used to illustrate the effectiveness of the media constructed using the proposed approach as absorbers for numerical grid truncation.
Information-Theoretic Limits on Sparsity Recovery in the High-Dimensional and Noisy Setting

The problem of sparsity pattern or support set recovery refers to estimating the set of nonzero coefficients of an unknown vector beta* isin Ropfp based on a set of n noisy observations. It arises in a variety of settings, including subset selection in regression, graphical model selection, signal denoising, compressive sensing, and constructive approximation. The sample complexity of a given method for subset recovery refers to the scaling of the required sample size n as a function of the signal dimension p, sparsity index k (number of non-zeroes in beta*), as well as the minimum value betamin of beta* over its support and other parameters of measurement matrix. This paper studies the information-theoretic limits of sparsity recovery: in particular, for a noisy linear observation model based on random measurement matrices drawn from general Gaussian measurement matrices, we derive both a set of sufficient conditions for exact support recovery using an exhaustive search decoder, as well as a set of necessary conditions that any decoder, regardless of its computational complexity, must satisfy for exact support recovery. This analysis of fundamental limits complements our previous work on sharp thresholds for support set recovery over the same set of random measurement ensembles using the polynomial-time Lasso method (lscr1-constrained quadratic programming).