cssi/SciSciGPT-SciSciNet huggingface dataset:
Micro-production functions aren't pretty: firm-level and industry-level specification for inputs and outputs

This study documents extreme variations in productivity within a panel of eleven firms in the same narrowly defined industry classification. Many of the sources of this variation were identified in field investigations of each plant.These investigations in turn allowed for the development of detailed specifications for inputs and outputs using data collected from the sites. The empirical estimates show that, irrespective of the precise functional form adopted, these detailed specifications, particularly those for output heterogeneity, are critical determinants of the performance of plant-level production functions. When the most detailed input and output specifications are used, 95% of the observed variation in plant production is explained. However, when the eleven firms are treated as an industry, less detailed specifications for inputs and outputs are shown to be more appropriate for explaining the variation in industry production.
Transfer matrices and lattice fermions at finite density

I discuss the connection between the Hamiltonian and path integral approaches for fermionic fields. I show how the temporal Wilson projection operators appear naturally in a lattice action. I also carefully treat the insertion of a chemical potential term.
Fast elliptic curve arithmetic and improved weil pairing evaluation

The side channel attack (SCA) is a serious attack on wearable devices that have scarce computational resources. Cryptographic algorithms on them should be efficient using small memory -- we have to make efforts to optimize the trade-off between efficiency and memory. In this paper we present efficient SCA-resistant scalar multiplications based on window method. Moller proposed an SPA-resistant window method based on 2w-ary window method, which replaces w-consecutive zeros to 1 plus w-consecutive 1 and it requires 2w points of table (or 2w-1 +1 points if the signed 2w-ary is used). The most efficient window method with small memory is the width-w NAF, which requires 2w-2 points of table. In this paper we convert the width-w NAF to an SPA-resistant addition chain. Indeed we generate a scalar sequence with the fixed pattern, e.g. |0..0x|0..0x|...|0..0x|, where x is positive odd points < 2w. Thus the size of the table is 2w-1, which is optimal in the construction of the SPA-resistant chain based on width-w NAF. The table sizes of the proposed scheme are 6% to 50% smaller than those of Moller's scheme for w = 2, 3, 4, 5, which are relevant choices in the sense of efficiency for 160-bit ECC.
Small-Business Lending and Profit Efficiency in Commercial Banking

We use nonparametric linear programming methods to calculate the directional distance function and the profit function for a random sample of banks from 1994 to 1999. The estimates imply that the gain in small-business lending from reducing technical inefficiency is minor compared to the gain possible from eliminating allocative inefficiency. Actual small-business lending early in the sample period is less than optimal, but the misallocation is confined to small banks. As a percentage of assets, small-business lending is larger for the most efficient banks.
Modeling Non-Circular Motions in Disk Galaxies: A Bar in NGC 2976

We give a brief description of a new model for non-circular motions in disk galaxy velocity fields, that does not invoke epicycles. We assume non-circular motions to stem from a bar-like or oval distortion to the potential, as could arise from a triaxial halo or a bar in the mass distribution of the baryons. We apply our model to the high-quality CO and Hα kinematics of NGC 2976 presented by [5]; it fits the data as well as their model with unrealistic radial flows, but yields a steeper rotation curve. Our analysis and other evidence suggests that NGC 2976 hosts a bar, implying a large baryonic contribution to the potential and thus limiting the allowed dark matter halo density.
Chandra observations of the pulsar wind nebula in SNR G0.9+0.1

We present observations with the Chandra X-Ray Observatory of the pulsar wind nebula (PWN) within the supernova remnant G0.9+0.1. At Chandra's high resolution, the PWN has a clear axial symmetry; a faint X-ray point source lying along the symmetry axis possibly corresponds to the pulsar itself. We argue that the nebular morphology can be explained in terms of a torus of emission in the pulsar's equatorial plane and a jet directed along the pulsar spin axis, as is seen in the X-ray nebulae powered by other young pulsars. A bright clump of emission within the PWN breaks the axisymmetry and may correspond to an intermediate-latitude feature in the pulsar wind.
Reactions of Indole with Nucleophiles

While indole naturally tends to act as a nucleophile, there are numerous examples of nucleophilic substitutions as well as nucleophilic additions to the indole ring system.
Asset pricing and intrinsic values: A review essay

The efficient markets hypothesis has dominated modern research on asset prices. Asset prices and their intrinsic values differ in inefficient financial markets but difficulties in the measurement of intrinsic value greatly complicate market efficiency tests. Reflections on the measurement of intrinsic value provide insight into the interpretation of existing evidence and suggestions for generating new evidence on market efficiency. This review essay on the state of knowledge about market efficiency focuses on "A Reappraisal of the Efficiency of Financial Markets", analyzing the research areas from this perspective: (1) short-run stock return predictability; (2) asset pricing anomalies; and (3) excess volatility and present value relations.
Join algorithms for the theory of uninterpreted functions

The join of two sets of facts, E1 and E2, is defined as the set of all facts that are implied independently by both E1 and E2. Congruence closure is a widely used representation for sets of equational facts in the theory of uninterpreted function symbols (UFS). We present an optimal join algorithm for special classes of the theory of UFS using the abstract congruence closure framework. Several known join algorithms, which work on a strict subclass, can be cast as specific instantiations of our generic procedure. We demonstrate the limitations of any approach for computing joins that is based on the use of congruence closure. We also mention some interesting open problems in this area.
Distributive Justice and CEO Compensation

This article develops a framework for studying individuals' ideas about what constitutes just compensation for chief executive officers (CEOs) and reports estimates of just CEO pay and the principles guiding ideas of justice. The sample consists of students pursuing a Master of Business Administration (MBA) degree in Sweden and the United States. The framework, based on justice theory and making use of Rossi's factorial survey method, enables assessment of ideas of fairness in CEO compensation, including (1) the just CEO compensation, in the eyes of each observer; (2) the principles of microjustice — observers' ideas about `who should get what' based on characteristics of CEOs and their firms; and (3) principles of macrojustice — ideas about the just level and dispersion in compensation across all CEOs. Our estimates yield the following main results: First, there is broad agreement on the median just CEO compensation but substantial inter-individual variation in the principles of microjustice and the othe...
Fuzziness and expert system generation

The Matrix Controlled Inference Engine (MACIE) style expert system uses a knowledge base automatically generated from a set of crisp training examples. However, when viewed from a fuzziness perspective, it is seen that the Pocket Algorithm which generates the knowledge base operates nondeterministically. Thus we have the fuzzy generation of a crisp expert system, rather than the usual crisp generation of a fuzzy expert system. It is also shown how MACIE can directly implement fuzzy expert systems.
M-complete approximate identities in operator spaces

This work introduces the concept of an M-complete approximate identity (M-cai) for a given operator subspace X of an operator space Y. M-cai's generalize central approximate identities in ideals in $C^*$-algebras, for it is proved that if X admits an M-cai in Y, then X is a complete M-ideal in Y. It is proved, using ``special'' M-cai's, that if $\cal J$ is a nuclear ideal in a $C^*$-algebra $\cal A$, then $\cal J$ is completely complemented in Y for any (isomorphically) locally reflexive operator space Y with $\cal J \subset Y \subset \cal A$ and $Y/\cal J$ separable. (This generalizes the previously known special case where $Y=\cal A$, due to Effros-Haagerup.) In turn, this yields a new proof of the Oikhberg-Rosenthal Theorem that $\cal K$ is completely complemented in any separable locally reflexive operator superspace, $\cal K$ the $C^*$-algebra of compact operators on $\ell^2$. M-cai's are also used in obtaining some special affirmative answers to the open problem of whether $\cal K$ is Banach-complemented in $\cal A$ for any separable $C^*$-algebra $\cal A$ with $\cal K\subset\cal A\subset B(\ell^2)$. It is shown that if conversely X is a complete M-ideal in Y, then X admits an M-cai in Y in the following situations: (i) Y has the (Banach) bounded approximation property; (ii) Y is 1-locally reflexive and X is $\lambda$-nuclear for some $\lambda \ge1$; (iii) X is a closed 2-sided ideal in an operator algebra Y (via the Effros-Ruan result that then X has a contractive algebraic approximate identity). However it is shown that there exists a separable Banach space X which is an M-ideal in $Y=X^{**}$, yet X admits no M-approximate identity in Y.
The Home Front: Rent Control and the Rapid Wartime Increase in Home Ownership

The U.S. home ownership rate rose by 10 percentage points between 1940 and 1945, despite severe restrictions on construction during World War II. I investigate whether wartime rent control played a role in this shift. The empirical test exploits variation in rent reductions across cities that had similar increases in rents prior to control. This variation does not appear to be correlated with underlying trends also driving home ownership. Greater initial rent reductions led to larger increases in home ownership; rent control can account for a significant share of the increase in home ownership over the early 1940s.
Oblique Impact of Two Cylinders in a Uniform Flow

The oblique motion of a circular cylinder through an inviscid and incompressible fluid, conveyed by a uniform flow at infinity, in the vicinity of another cylinder fixed in space is considered. In a relative polar co-ordinate system moving with the stream, the kinetic energy of the fluid is expressed as a function of six added masses due to motions parallel and perpendicular to the line joining the centres of the cylinder pair. The Lagrange equations of motion are then integrated for the trajectories of the moving cylinder. In order to evaluate the added masses and their derivatives with respect to the separation distance between the cylinders in terms of the hydrodynamic singularities, the method of successive images, initiated by Hicks, and the Taylor added-mass formula are applied, and analytic solutions in closed form are obtained thereafter. The dynamic behaviour of a drifting body in close proximity of a fixed one is investigated by considering the limiting values of the fluid kinetic energy and the interaction forces on each body. The reliability of the numerical approximation of added masses and their derivatives is also discussed in the present study. The integral equations, in terms of surface source distributions and also discussed in the present study. The integral equations, in terms of surface source distributions and their derivatives on both circles, are carefully modified for obtaining accurate numerical solutions.
Critical success factors: How one multinational company develops global e-learning.

This research study examined how a multinational company determined what the critical success factors (CSFs) were for developing global e-learning. The study analyzed how these CSFs were grouped together in order to make their management more efficient. There were 21 participants in the study who were key stakeholders and came from one of four groups: headquarters, external vendor, regional, and overseas personnel. The results demonstrated that not all CSFs were deemed critical for every program and that what were considered CSFs early in the project often changed by the end of the project. Additionally, the study showed that grouping the CSFs into common categories allowed the program development stakeholders to be more consistent and thorough in their ability to manage those CSFs throughout the project. Another outcome of the study suggested that what were often considered as CSFs for global, multinational programs were also important factors in developing a single market program where the learners were culturally, socially, linguistically and academically diverse. Finally, the results demonstrated that the best way to manage CSFs, at least for the study company, was to develop best practices and SOPs which prescribe the actions needed to address them. The nature of these outcomes suggested that these approaches could be generalized to other companies that wished to develop global e-learning programs.
MAP estimation, message passing, and perfect graphs

Efficiently finding the maximum a posteriori (MAP) configuration of a graphical model is an important problem which is often implemented using message passing algorithms. The optimality of such algorithms is only well established for singly-connected graphs and other limited settings. This article extends the set of graphs where MAP estimation is in P and where message passing recovers the exact solution to so-called perfect graphs. This result leverages recent progress in defining perfect graphs (the strong perfect graph theorem), linear programming relaxations of MAP estimation and recent convergent message passing schemes. The article converts graphical models into nand Markov random fields which are straightforward to relax into linear programs. Therein, integrality can be established in general by testing for graph perfection. This perfection test is performed efficiently using a polynomial time algorithm. Alternatively, known decomposition tools from perfect graph theory may be used to prove perfection for certain families of graphs. Thus, a general graph framework is provided for determining when MAP estimation in any graphical model is in P, has an integral linear programming relaxation and is exactly recoverable by message passing.
Stabilizer quantum codes: A unified view based on Forney-style factor graphs

Quantum error-correction codes (QECCs) are a vital ingredient of quantum computation and communication systems. In that context it is highly desirable to design QECCs that can be represented by graphical models which possess a structure that enables efficient and close-to-optimal iterative decoding. In this paper we focus on stabilizer QECCs, a class of QECCs whose construction is rendered non-trivial by the fact that the stabilizer label code, a code that is associated with a stabilizer QECC, has to satisfy a certain self-orthogonality condition. In order to design graphical models of stabilizer label codes that satisfy this condition, we extend a duality result for Forney-style factor graphs (FFGs) to the stabilizer label code framework. This allows us to formulate a simple FFG design rule for constructing stabilizer label codes, a design rule that unifies several earlier stabilizer label code constructions.
Variational Principles and Methods in Theoretical Physics and Chemistry

Preface Part I. Classical Mathematics and Physics: 1. History of variational theory 2. Classical mechanics 3. Applied mathematics Part II. Bound States in Quantum Mechanics: 4. Time-independent quantum mechanics 5. Independent-electron models 6. Time-dependent theory and linear response Part III. Continuum States and Scattering Theory: 7. Multiple scattering theory for molecules and solids 8. Variational methods for continuum states 9. Electron-impact rovibrational excitation of molecules Part IV. Field Theories: 10. Relativistic Lagrangian theories.
Falcon Reactor-Pumped Laser Technology for Space Power Applications

The FALCON reactor-pumped laser program is investigating concepts for high power laser systems pumped directly by fission energy from a nuclear reactor. The direct pumping of laser media with fission energy offers the potential system advantages of scaling to very high laser powers with long run times, extremely compact and low-mass energy storage, and relatively simple gain generator design. Reactor pumping has been studied in the ACRR and SPR research reactor facilities at Sandia National Laboratories. Based on these experiments and extensive system analysis, large reactor-pumped laser systems have been evaluated for extraction efficiency, beam quality, and practicality (considering auxiliary power needs, radiation damage to optical components, rejection of waste heat, and expected imperfections in excitation structures). It appears that high-power reactor-pumped lasers can be developed in the near term to provide important capabilities for the exploration and utilization of space.
Direct and bulk‐scattered forward‐shock emissions: sources of X‐ray afterglow diversity

I describe the modifications to the standard forward‐shock model required to account for the X‐ray light‐curve features discovered by Swift in the early afterglow emission and propose that a delayed, pair‐enriched, and highly relativistic outflow, which bulk‐scatters the forward‐shock synchrotron emission, yields sometimes a brighter X‐ray emission, producing short‐lived X‐ray flares, X‐ray light‐curve plateaus ending with chromatic breaks, and fast post‐plateau decays.
NON-LINEAR VACUUM POLARIZATION IN STRONG FIELDS

A particularly interesting consequence of the Dirac equation and hole theory is the phenomenon of spontaneous e+e− pair creation in strong static electric fields1–3. Normally, pair creation in a static field costs energy, ΔE = 2me − B, where B is the binding energy of the electron. Consequently, spontaneous pair creation is normally a virtual process lasting only a short time, Δ τ ∿ 1/ΔE ∿ (2me − B)−1. This virtual process is called vacuum polarization in Quantum Electrodynamics (QED). However, if the external fields become so strong that B → 2me, then Δ τ → ∞, and the virtual pair can “materialize”. In terms of QED this would be called real or on-shell vacuum polarization.
Case study: Nordic Windpower's critical blade failures

In 2007, the start-up wind turbine generator (WTG) manufacturer, Nordic Windpower, officially launched in North America as a merger between Swedish, US, and UK development teams. Based on a design researched and funded by the Swedish Government, Nordic Windpower developed the N1000, a 2-bladed, 1MW WTG geared toward the distributed and community wind market. The N1000 was the first utility-scale, 2-bladed WTG of its size in North America. It was specifically the features of the 2-bladed design that made the WTG ideal for the community wind market—a growing market, whose capacity was expected to reach 600MW in the US in 2009, and the only market for which Nordic Windpower had a product offering. Serial production of the N1000 began in 2009, producing a total of eight units, with three units being installed in the US. During commissioning, field testing, and after grid production, repeated failures of the fixed-pitch and stall-regulated rotor braking system prevented Nordic Windpower from meeting contractual obligations. On August 28, 2013, Nordic Windpower LLC liquidated the business under Chapter 7. This case study examines Nordic Windpower's critical blade failures from a Systems Engineering perspective, identifies best practices, and offers potential solutions for Nordic Windpower's development process. Nordic Windpower Company Profile: • 1975: Research and development began in Sweden. • 2007: Investors from the UK brought the turbine to the US market as Nordic Windpower LLC, officially launching the company. • 2009: N1000 began serial production. • 2012: 8 total turbines sold, produced, and installed since starting production. • 2013: Nordic Windpower LLC liquidated assets under Chapter 7.
Continuum and Lattice Coulomb-Gauge Hamiltonian

We review the canonical quantization of continuum Yang-Mills theory, and derive the continuum Coulomb-gauge Hamiltonian by a simplification of the Christ-Lee method. We then analogously derive, by a simple and elementary method, the lattice Coulomb-gauge Hamiltonian in the minimal Coulomb gauge (and in other Coulomb gauges) from the known Kogut-Susskind Hamiltonian.
Gravitational softening as a smoothing operation

In self-consistent N-body simulations of collisionless systems, gravitational interactions are modified on small scales to remove singularities and simplify the task of numerically integrating the equations of motion. This ‘gravitational softening’ is sometimes presented as an ad hoc departure from Newtonian gravity. However, softening can also be described as a smoothing operation applied to the mass distribution; the gravitational potential and the smoothed density obey Poisson's equation precisely. While ‘softening’ and ‘smoothing’ are mathematically equivalent descriptions, the latter has some advantages. For example, the smoothing description suggests a way to set up N-body initial conditions in almost perfect dynamical equilibrium.
On the Castelnuovo-Mumford regularity of connected curves

In this paper we prove that the regularity of a connected curve is bounded by its degree minus its codimension plus 1. We also investigate the structure of connected curves for which this bound is optimal. In particular, we construct connected curves of arbitrarily high degree in P 4 having maximal regularity, but no extremal secants. We also show that any connected curve in P 3 of degree at least 5 with maximal regularity and no linear components has an extremal secant.
New Results on Stock Prices and Fundamental Value

The S&P 500 Index is valued using the discounted dividend model, corrected for share repurchases. Under more optimistic, but not unreasonable assumptions, the S&P 500 index is not overvalued, and therefore may reflect underlying fundamental value.
Magnetic field-induced reversible phase transformation in magnetic shape memory alloys

Magnetic Shape Memory Alloys (MSMAs) are promising high-frequency active materials for actuation, sensing, shape control, vibration suppression and energy harvesting applications. The macroscopic functionality of MSMAs originates from the coupled evolution of highly heterogeneous magnetic and elastic domain microstructures. Microstructure dependence of phase transformations in MSMAs introduces internal variables into the model to account for strong effects of domain microstructure processes on MSMA properties and varying elastic and magnetic coupling. Selection of internal variables and their incorporation into constitutive modeling has been done for the problem of field-induced martensite reorientation. Introducing a new internal variable, the austenitic volume fraction, the study of field induced phase transformation between the parent and martensitic phases is performed.
Learning from the Success of MPI

The Message Passing Interface (MPI) has been extremely successful as a portable way to program high-performance parallel computers. This success has occurred in spite of the view of many that message passing is difficult and that other approaches, including automatic parallelization and directive-based parallelism, are easier to use. This paper argues that MPI has succeeded because it addresses all of the important issues in providing a parallel programming model.
Protracted effects of chronic stress on serotonin-dependent thermoregulation

Chronic stress is known to affect serotonin (5HT) neurotransmission in the brain and to alter body temperature. The body temperature is controlled in part, by the medial preoptic area (mPOA) of the hypothalamus. To investigate the effect of chronic stress on 5HT and how it affects body temperature regulation, we examined whether exposure to a chronic unpredictable stress (CUS) paradigm produces long-term alterations in thermoregulatory function of the mPOA through decreased 5HT neurotransmission. Adult male Sprague-Dawley rats underwent 21 d of CUS. Four days after the last stress exposure, basal body temperature in the home cage and body temperature in a cold room maintained at 10 °C were recorded. The CUS rats had significantly higher subcutaneous basal body temperature at 13:00 h compared to unstressed (NoStress) rats. Whereas the NoStress rats were able to significantly elevate body temperature from basal levels at 30 and 60 min of exposure to the cold room, the CUS rats showed a hypothermic response to the cold. Treatment during CUS with metyrapone, a corticosterone synthesis inhibitor, blocked stress-induced decrease in body temperature in response to the cold challenge. CUS also decreased 5HT transporter protein immunoreactivity in the mPOA and 5HT2A/C agonist injection into the mPOA after CUS exposure caused stressed rats to exhibit a sensitized hyperthermic response to cold. These results indicate that the CUS induced changes to the 5HTergic system alter mPOA function in thermoregulation. These findings help us to explain the mechanisms underlying chronic stress-induced disorders such as chronic fatigue syndrome wherein long lasting thermoregulatory deficits are observed.
Public-key steganography with active attacks

A complexity-theoretic model for public-key steganography with active attacks is introduced. The notion of steganographic security against adaptive chosen-covertext attacks (SS-CCA) and a relaxation called steganographic security against publicly-detectable replayable adaptive chosen-covertext attacks (SS-PDR-CCA) are formalized. These notions are closely related to CCA-security and PDR-CCA-security for public-key cryptosystems. In particular, it is shown that any SS-(PDR-)CCA stegosystem is a (PDR-)CCA-secure public-key cryptosystem and that an SS-PDR-CCA stegosystem for any covertext distribution with sufficiently large min-entropy can be realized from any PDR-CCA-secure public-key cryptosystem with pseudorandom ciphertexts.
The Kindergarten Rule of Sustainable Growth

The relationship between economic growth and the environment is not well understood: we have only limited understanding of the basic science involved and very limited data. Because of these difficulties it is especially important to develop a series of relatively simple theoretical models that generate stark predictions. This paper presents one such model where societies implement the Kindergarten rule of sustainable growth.' Following the Kindergarten rule means implementing zero emission technologies in either finite time or asymptotically. The underlying simplicity of the model allows us to provide new predictions linking the path of environmental quality to pollutant characteristics (stocks vs. flows; toxics vs. irritants) and primitives of the economic system. It also provides a novel Environmental Catch-up Hypothesis.
Hardware Encapsulation of Security Services

Hardware security modules can be used to encapsulate simple security services that bind security functions such as decryption with authorisation and authentication. Such hardware secured services provide a functional root of trust that can be placed within context of a wider IT solution hence enabling strong separations of control and duty.
Compliance with IMF Program Indicators and Growth in Transition Economies

This paper makes use of the International Monetary Fund's (IMF) Database for Monitoring Fund Arrangements (MONA) to investigate whether transition countries that more successfully implement the con...
A New Outer Bound via Interference Localization and the Degrees of Freedom Regions of MIMO Interference Networks With No CSIT

The two-user multiple-input multiple-output (MIMO) interference and cognitive radio channels are considered, where the ith transmitter and the ith receiver have Mi and Ni antennas, respectively. In particular, the degrees of freedom (DoF) regions of these channels are studied under the assumption of having no channel state information at the transmitters. Making certain assumptions about the distributions of channel matrices of increasing generality respectively, Huang, Zhu and Guo, and the authors of this paper characterized the DoF region of the MIMO interference channel for all values of the four-tuple (M1, M2, N1, N2), except when min(M1, N1) >; N2 >; M2 or min(M2, N2) >; N1 >; M1. More recently, for isotropic fading distributions, Zhu and Guo have solved this latter case by providing a tight outer bound to the DoF region. Here, a simpler and more widely applicable proof of that outer bound is given based on the idea of interference localization. Using the same idea, under Rayleigh fading, the DoF region is then also established for the MIMO cognitive radio channel (when the second transmitter is cognitive) with min(M1+M2, N1) >; N2 >; M2-the only class for which the inner and outer bounds previously reported by the authors were not tight-thereby completing the DoF region characterization of this channel under Rayleigh fading for all values of (M1, M2, N1, N2).
Direct Visualization of the Perforant Pathway in the Human Brain with Ex Vivo Diffusion Tensor Imaging

Ex vivo magnetic resonance imaging yields high resolution images that reveal detailed cerebral anatomy and explicit cytoarchitecture in the cerebral cortex, subcortical structures, and white matter in the human brain. Our data illustrate neuroanatomical correlates of limbic circuitry with high resolution images at high field. In this report, we have studied ex vivo medial temporal lobe samples in high resolution structural MRI and high resolution diffusion MRI. Structural and diffusion MRIs were registered to each other and to histological sections stained for myelin for validation of the perforant pathway. We demonstrate probability maps and fiber tracking from diffusion tensor data that allows the direct visualization of the perforant pathway. Although it is not possible to validate the DTI data with invasive measures, results described here provide an additional line of evidence of the perforant pathway trajectory in the human brain and that the perforant pathway may cross the hippocampal sulcus.
Windfall Management for Poverty Reduction : Improving Public Finance Management, The Case of Chad

This paper aims at providing a guide to ensure efficiency in the management of Chad's windfall to support the development process and poverty reduction. The analysis is based on the lessons and experience of countries that have successfully used natural-resource-generated windfalls to launch their development process while avoiding the natural resource curse. The paper also discusses the petroleum management arrangements in place in Chad for poverty reduction. The author argues that the successful management of Chad's windfall for poverty reduction will depend on the effectiveness of oil revenue management arrangements in place in Chad and the government's willingness to improve public finance management (PFM).
A global urban risk index

Which cities have the highest risk of human and economic losses due to natural hazards? And how will urban exposure to major hazards change over the coming decades? This paper develops a global urban disaster risk index that evaluates the mortality and economic risks from disasters in 1,943 cities in developing countries. Concentrations of population, infrastructure, and economic activities in cities contribute to increased exposure and susceptibility to natural hazards. The three components of this risk measure are urban hazard characteristics, exposure, and vulnerability. For earthquakes, cyclones, floods, and landslides, single hazard risk indices are developed. In addition, a multi-hazard index gives a holistic picture of current city risk. Demographic-economic projection of city population growth to 2050 suggests that exposure to earthquake and cyclone risk in developing country cities will more than double from today's levels. Global urban risk analysis, as presented in this paper, can inform the prioritization of resources for disaster risk management and urban planning and promote the shift toward managing risks rather than emergencies.
The [U2I10]2– Anion: Synthesis and Structure of [Ta7(Se2)14][U2I10]2

The new anion (U2I10) 2- has been isolated in the compound (Ta7(Se2)14)(U2I10)2. This compound was synthesized from the ele- ments at 1173 K. It crystallizes in space group Cccm of the orthorhom- bic system with four formula units in a cell of dimensions a = 21.5134(9) A, b = 22.1619(9) A, and c = 16.7834(6) A. The crystal structure comprises infinite (Ta(Se2)2)n cationic chains charge balanced
Incremental knowledge base construction using DeepDive

Populating a database with unstructured information is a long-standing problem in industry and research that encompasses problems of extraction, cleaning, and integration. Recent names used for this problem include dealing with dark data and knowledge base construction (KBC). In this work, we describe DeepDive, a system that combines database and machine learning ideas to help develop KBC systems, and we present techniques to make the KBC process more efficient. We observe that the KBC process is iterative, and we develop techniques to incrementally produce inference results for KBC systems. We propose two methods for incremental inference, based respectively on sampling and variational techniques. We also study the tradeoff space of these methods and develop a simple rule-based optimizer. DeepDive includes all of these contributions, and we evaluate DeepDive on five KBC systems, showing that it can speed up KBC inference tasks by up to two orders of magnitude with negligible impact on quality.
Modeling winter rainfall in Northwest India using a hidden Markov model: understanding occurrence of different states and their dynamical connections

A multiscale-modeling framework for daily rainfall is considered and diagnostic results are presented for an application to the winter season in Northwest India. The daily rainfall process is considered to follow a hidden Markov model (HMM), with the hidden states assumed to be an unknown random function of slowly varying climatic modulation of the winter jet stream and moisture transport dynamics. The data used are from 14 stations over Satluj River basin in winter (December–January–February–March). The period considered is 1977/78–2005/06. The HMM identifies four discrete weather states, which are used to describe daily rainfall variability over study region. Each state was found to be associated with a distinct atmospheric circulation pattern, with the driest and drier states, State 1 and 2 respectively, characterized by a lack of synoptic wave activity. In contrast, the wetter and wettest states, States 3 and 4 respectively, are characterized by a zonally oriented wave train extending across Eurasia between 20N and 40N, identified with ‘western disturbances’ (WD). The occurrence of State 4 is strongly conditioned by the El Nino and Indian Ocean Dipole (IOD) phenomena in winter, which is demonstrated using large-scale correlation maps based on mean sea level pressure and sea surface temperature. This suggests that there is a tendency of higher frequency of the wet days and intense WD activities in winter during El Nino and positive IOD years. These findings, derived from daily rainfall station records, help clarify the sequence of Northern Hemisphere mid-latitude storms bringing winter rainfall over Northwest India, and their association with potentially predictable low frequency modes on seasonal time scales and longer.
Language development from two to three

Part I. Acquisition of Simple Sentences: 1. Syntactic, lexical, and discourse covariation 2. Sentence negation 3. Verb inflections and tense 4. Aspect 5. Wh-questions Part II: Acquisition of Complex Sentences: 6. Syntactic connectives and clausal meaning relations 7. Structures and functions of expression of causality 8. Meaning of expressions of causality 9. Infinitive constructions 10. Complentation Part III: Studies of Process: 11. Imitation 12. Discourse.
A modest proposal for vector extensions to ALGOL

Machines that possess instructions that are actually “higher level” than high-level language statements require extensions to traditional programming language. This paper explores the kinds of extensions necessary for adequate access to the CDC STAR instruction set. Specific problem areas considered are: access to the vector instructions, definition of descriptors, support of the variety of hardware data-types, and facilities for memory and register management.It is fairly straightforward to define language facilities to cover most of these problems with minimum disruption of existing language features. Informal descriptions are given for syntactic and semantic extensions to ALA, an ALGOL based language. Features include declaration and usage of vector and descriptor variables, generation of vector values, subscripting slicing, and procedure linkage. The language constructs described are not limited in application to either the STAR or ALA. They should be easily adaptable to other languages and machines where vector constructs would enhance programming power.
Probing Bose-Einstein Condensates with Optical Bragg Scattering

Gaseous Bose-Einstein condensates are a macroscopic condensed-matter system which can be understood from a microscopic, atomic basis. We present examples of how the optical tools of atomic physics can be used to probe properties of this system. In particular, we describe how stimulated light scattering can be used to measure the coherence length of a condensate, to measure its excitation spectrum, and to reveal the presence of pair excitations in the many-body condensate wavefunction.
On the existence of angular correlations in decays with heavy matter partners

If heavy partners of the Standard Model matter fields are discovered at the LHC it will be imperative to determine their spin in order to uncover the underlying theory. In decay chains, both the spin and the mass hierarchy of all particles involved can influence the resulting angular correlations. We present the necessary conditions for decays involving the matter partners to exhibit angular correlations. In particular we find that when the masses are not degenerate, a heavy fermionic sector always displays angular correlations in cascade decays. When the masses are closely degenerate the size of spin effects is controlled by a global phase parameter. In a large region of the parameter space, correlations are strongly suppressed. In other regions, such as in UED model where this phase is fixed by 5-d Lorentz invariance, the correlations are pronounced. In addition, we show that in certain cases one may even have enough information to determine the spin of other heavy partners involved in the decay (such as the Lightest Stable Partner or a heavy gluon).
A novel synthesis of substituted imidazoles, and a reexamination of a purported chymotrypsin model

Abstract Rearrangement of an N-hydroxyimidazole to a side-chain functionalized derivative permits easy synthesis of a purported chymotrypsin mimic that contains a “catalytic triad” as part of a cyclodextrin molecule. Contrary to the previous claims, the added functional groups do not play a role in the cyclodextrin reaction with a typical substrate, but in fact slow the reaction because of steric hindrance.
Optimal Process Planning for Laser Forming of Doubly Curved Shapes

There has been a considerable amount of work carried out on two-dimensional laser forming. In order to advance the process further for industrial applications, however, it is necessary to consider more general cases and especially their process planning aspect. This paper presents an optimal approach to laser scanning paths and heating condition determination for laser forming of doubly curved shapes. Important features of the approach include the strain field calculation based on principal curvature formulation and minimal strain optimization, and scanning paths and heating condition (laser power and scanning velocity) determination by combining analytical and practical constraints. The overall methodology is presented first, followed by more detailed descriptions of each step of the approach. Two distinctive types of doubly curved shape, pillow and saddle shapes are focused on and the effectiveness of the proposed approach is validated by forming experiments.
Spectropolarimetry and Modeling of the Eclipsing T Tauri Star KH 15D

KH 15D is a strongly variable T Tauri star in the young star cluster NGC 2264 that shows a decrease in flux of 3.5 mag lasting for 18 days and repeating every 48 days. The eclipsing material is likely due to orbiting dust or rocky bodies in a partial ring or warped disk that periodically occults the star. We measured the polarized spectrum in and out of eclipse at the Keck and Palomar observatories. Outside of the eclipse, the star exhibited low polarization consistent with zero. During eclipse, the polarization increased dramatically to ~2% across the optical spectrum, while the spectrum had the same continuum shape as outside of eclipse and exhibited emission lines of much larger equivalent width, as previously seen. From the data, we conclude that (1) the scattering region is uneclipsed, (2) the scattering is nearly achromatic, and (3) the star is likely completely eclipsed so that the flux during eclipse is entirely due to scattered light, a conclusion also argued for by the shape of the ingress and egress. We argue that the scattering is not due to electrons but may be due to large dust grains of size ~10 μm, similar to the interplanetary grains that scatter the zodiacal light. We construct a warped-disk model with an extended dusty atmosphere that reproduces the main features of the light curve, namely, (1) a gradual decrease before ingress due to extinction in the atmosphere (similar for egress), (2) a sharper decrease within ingress due to the optically thick base of the atmosphere, and (3) a polarized flux during eclipse that is 0.1% of the total flux outside of eclipse, which requires no fine-tuning of the model. The inclination of the warp is set by the duration of ingress and egress assuming that the warp is located at the Keplerian radius, and the inclination of the observer is then determined by the duration of the eclipse.
MaxWeight Scheduling: Asymptotic Behavior of Unscaled Queue-Differentials in Heavy Traffic

The model is a "generalized switch", serving multiple traffic flows in discrete time. The switch uses MaxWeight algorithm to make a service decision (scheduling choice) at each time step, which determines the probability distribution of the amount of service that will be provided. We are primarily motivated by the following question: in the heavy traffic regime, when the switch load approaches critical level, will the service processes provided to each flow remain "smooth" (i.e., without large gaps in service)? Addressing this question reduces to the analysis of the asymptotic behavior of the unscaled queue-differential process in heavy traffic. We prove that the stationary regime of this process converges to that of a positive recurrent Markov chain, whose structure we explicitly describe. This in turn implies asymptotic "smoothness" of the service processes.
F-theory, SO(32) and Toric Geometry

Abstract We show that the F-theory dual of the heterotic string with unbroken Spin(32)/ Z 2 symmetry in eight dimensions can be described in terms of the same polyhedron that can also encode unbroken E 8 × E 8 symmetry. By considering particular compactifications with this K 3 surface as a fiber, we can reproduce the recently found ‘record gauge group’ in six dimensions and obtain a new ‘record gauge group’ in four dimensions. Our observations relate to the toric diagram for the intersection of components of degenerate fibers and our definition of these objects, which we call ‘tops’, is more general than an earlier definition by Candelas and Font.
Palladium-catalyzed reactions of hypophosphorous compounds with allenes, dienes, and allylic electrophiles: methodology for the synthesis of allylic h-phosphinates.

Hypophosphorous compounds (MOP(O)H2, M = H, R3NH) effectively participate in metal-catalyzed C−P bond-forming reactions with allenes, dienes, and activated allylic electrophiles under mild conditions. The catalytic system Pd2dba3/xantphos is crucial to avoid or minimize the competitive reductive transfer-hydrogenation pathway available to hypophosphorous acid derivatives. Further investigation into the allylation mechanism provided access to the analogy allylic acetate−allylic phosphinate, which then led to the development of a Pd-catalyzed rearrangement of preformed allylic phosphinates esters and, ultimately, to a catalytic dehydrative allylation of hypophosphorous acid with allylic alcohols. The reactions disclosed herein constitute efficient synthetic approaches, not only to prepare allylic H-phosphinic acids but also their esters via one-pot tandem processes. In addition, the potential of H-phosphinates as useful synthons for the preparation of other organophosphorus compounds is demonstrated.
Solar Array Degradation due to Meteoroid Impacts during Extended Planetary Missions

Power loss due to cumulative meteoroid impacts on solar cells during extended planetary missions, investigating hypervelocity particle impacts into glass
Approximate converse theorem

We present an approximate converse theorem which measures how close a given set of irreducible admissible unramified unitary generic local representations of GL(n) is to a genuine cuspidal representation. To get a formula for the measure, we introduce a quasi-Maass form on the generalized upper half plane for a given set of local representations. We also construct an annihilating operator which enables us to write down an explicit cuspidal automorphic function.
Screening length in (2+1)-dimensional Abelian Chern–Simons theories

Abstract In this Letter, we systematically study the question of screening length in Abelian Chern–Simons theories. In the Abelian Higgs theory, where there are two massive poles in the gauge propagator at the tree level, we show that the coefficient of one of them becomes negligible at high temperature and that the screening length is dominantly determined by the parity violating part of the self-energy. In this theory, static magnetic fields are screened. In the fermion theory, on the other hand, the parity conserving part of the self-energy determines the screening length and static magnetic fields are not screened. Several other interesting features are also discussed.
On the formation of singularities in the critical $O(3)$ $\sigma$-model

We study the phenomena of energy concentration for the critical O(3) sigma model, also known as the wave map flow from ℝ 2+1 Minkowski space into the sphere S 2 . We establish rigorously and constructively existence of a set of smooth initial data resulting in a dynamic finite time formation of singularities. The construction and analysis are done in the context of the k-equivariant symmetry reduction, and we restrict to maps with homotopy class k ≥ 4. The concentration mechanism we uncover is essentially due to a resonant self-focusing (shrinking) of a corresponding harmonic map. We show that the phenomenon is generic (e.g. in certain Sobolev spaces) in that it persists under small perturbations of initial data, while the resulting blowup is bounded by a log-modified self-similar asymptotic.