cssi/SciSciGPT-SciSciNet huggingface dataset:
Logarithmically Scalable Routing Algorithms in Large Optical Networks

In this paper, we present three logarithmically scalable routing algorithms for very large optical networks. The algorithms are based on a hierarchical approach. Each algorithm requires a different amount of information to be stored at each node, and results in a different efficiency. The network capacity provided by each algorithm is compared with that provided by the global shortest path algorithm (which is not scalable). It is found that the network capacities of the three algorithms are almost the same as that of the global shortest path algorithm. For fixed routing algorithms, we use an approximate analysis, appeared in the literature, from which the blocking probability at a fixed network load can iterately be obtained (we use call blocking probability as our quality objective and compare network capacity by observing the difference in the offered load which produces the same blocking probability). The approximate analysis is validated through simulation and is found to be very accurate. Scalable, quasi-dynamic routing algorithms are also studied. Numerical results show that, when the node-capacity is equal to the capacity of a single wavelength and the bandwidth required per call is large (greater than 24% of the link capacity), the capacity provided by the quasi-dynamic routing algorithm is very close to that of an infinite capacity centralized switch (lowest possible call blocking caused exclusively by congestion on the finite capacity user input/output links, never by the switch fabric itself). In all the examples considered, the improvement of the quasi-dynamic routing algorithm over the fixed routing algorithm is significant.
Markov logic in infinite domains

Combining first-order logic and probability has long been a goal of AI. Markov logic (Richardson & Domingos, 2006) accomplishes this by attaching weights to first-order formulas and viewing them as templates for features of Markov networks. Unfortunately, it does not have the full power of first-order logic, because it is only defined for finite domains. This paper extends Markov logic to infinite domains, by casting it in the framework of Gibbs measures (Georgii, 1988). We show that a Markov logic network (MLN) admits a Gibbs measure as long as each ground atom has a finite number of neighbors. Many interesting cases fall in this category. We also show that an MLN admits a unique measure if the weights of its non-unit clauses are small enough. We then examine the structure of the set of consistent measures in the non-unique case. Many important phenomena, including systems with phase transitions, are represented by MLNs with non-unique measures. We relate the problem of satisfiability in first-order logic to the properties of MLN measures, and discuss how Markov logic relates to previous infinite models.
Administrative Costs and the Organization of Individual Retirement Account Systems : A Comparative Perspective

What is the most cost-effective way to organize individual accounts that are part of a mandatory social security system? Defined-contribution individual account components of social security systems are criticized for being too expensive. The authors investigate the cost-effectiveness of two methods for constructing mandatory individual accounts: a) Investing through the retail market with relatively open choice among investment companies (the method first used by Chile and adopted by most Latin American countries). b) Investing through the institutional market with constrained choice. For the retail market, they use data from mandatory pension funds in Chile and other Latin American countries and from voluntary mutual funds in the United States. For the institutional market, they use data from systems in Bolivia and Sweden and from larger pension plans and the federal Thrift Saving Plan in the United States. The institutional approaches aggregate numerous small accounts into large blocks of money and negotiate fees on a centralized basis, often through competitive bidding. They retain workers' choice o some funds. Fees and costs are kept low by reducing incentives for marketing, avoiding excess capacity at system start-up, and constraining choice to investment portfolio that are inexpensive to manage. In developed financial markets, the biggest potential cost saving stems from constrained portfolio choice, especially from a concentration on passive investment. The biggest cost saving for a given portfolio and for countries with weak financial markets comes from reduced marketing activities. In the retail market, where annualized fees and costs range from 0.8 percent to 1.5 percent of assets, use of the institutional market in individual retirement account systems has reduced those fees and costs to less than 0.2 percent to 0.6 percent of assets. This reduction can increase pensions by 10 - 20 percent relative to the retail market. Countries that can surmount rebidding problems, weaker performance incentives, inflexibility in the face of unforeseen contingencies, and an increased probability of corruption, collusion, and regulatory capture should seriously consider the institutional approach, especially at the start-up of a new multipillar system or for systems with small asset bases.
Non-minimal triangulations for mixed stochastic/deterministic graphical models

We observe that certain large-clique graph tri-angulations can be useful for reducing computational requirements when making queries on mixed stochastic/deterministic graphical models. We demonstrate that many of these large-clique triangulations are non-minimal and are thus unattainable via the elimination algorithm. We introduce ancestral pairs as the basis for novel triangulation heuristics and prove that no more than the addition of edges between ancestral pairs need be considered when searching for state space optimal triangulations in such graphs. Empirical results on random and real world graphs are given. We also present an algorithm and correctness proof for determining if a triangulation can be obtained via elimination, and we show that the decision problem associated with finding optimal state space triangulations in this mixed setting is NP-complete.
Recent advances in structural technology for large deployable and erectable spacecraft

Ultra-low mass deployable and erectable truss structure designs for spacecraft are identified using computerized structural sizing techniques. Extremely slender strut proportions are shown to characterize minimum mass spacecraft which are designed for Shuttle transport to orbit. Analytical results are presented which demonstrate discrete element effects using a recently developed buckling theory for periodic lattice type structures. An analysis of fabrication imperfection effects on the surface accuracy of four different antenna reflector structures is summarized. This study shows the tetrahedral truss to have the greatest potential of the structures examined for application to accurate or large reflectors. A deployable module which can be efficiently transported is identified and shown to have significant potential for application to future antenna requirements. Recent investigations of erectable structure assembly are reviewed. Initial experiments simulating astronaut assembly by extra-vehicular activity (EVA) show that a pair of astronauts can achieve assembly times of 2-5 min/strut. Studies indicate that an automated assembler can achieve times of less than 1 min/strut on an around-the-clock basis.
An automata-theoretic approach to linear temporal logic

The automata-theoretic approach to linear temporal logic uses the theory of automata as a unifying paradigm for program specification, verification, and synthesis. Both programs and specifications are in essence descriptions of computations. These computations can be viewed as words over some alphabet. Thus, programs and specifications can be viewed as descriptions of languages over some alphabet. The automata-theoretic perspective considers the relationships between programs and their specifications as relationships between languages. By translating programs and specifications to automata, questions about programs and their specifications can be reduced to questions about automata. More specifically, questions such as satisfiability of specifications and correctness of programs with respect to their specifications can be reduced to questions such as nonemptiness and containment of automata.
Chapter 6 – Metabolic Systems

Animal cells must be capable of transforming the chemical energy in the environment into electrical, mechanical, osmotic, and other forms of chemical energy in order to maintain essential life processes, such as nervous transmission, muscle contraction, and the synthesis of structural components. The sources of transformed energy include ingested food, which contains complex carbohydrates, fats, and proteins that are broken down in the alimentary tract to simpler components and absorbed through the wall of the midgut into the hemolymph. The circulatory system then transports these components to all the cells of the body, which break them down even further and capture the chemical energy they contain. Each cell may use the components immediately, or they may be used to synthesize reserves for later use. These processes of food breakdown, utilization, and storage are strikingly similar in insects and vertebrates, as well as in most other living things. However, there are also some distinctive metabolic processes that are found only in insects.
The no-surplus condition as a characterization of perfectly competitive equilibrium☆

Publisher Summary In the Walrasian definition of competitive equilibrium, attention is confined to the consistency of individuals' plans on the presumption that each agent regards itself as a price-taker. Thus, Walrasian equilibrium may exist where there is no supporting evidence for that presumption,for example, in an economy with a small number of agents. The self-imposed limitations of the definition imply that it describes necessary but not sufficient conditions for perfectly competitive equilibrium, that is, an equilibrium for which the presumption of price-taking is justified. This chapter presents an alternative definition that brings out the perfectly competitive character of the equilibrium that is implicitly behind the usual interpretation. The approach adopted has as a basic premise that the description of perfect competition should be invariant to the number of agents. Contrary to what appears to be the typical view that it is logically tied to the study of economies with large numbers of agents, it is found that an analysis of the conditions for perfectly competitive equilibrium with small numbers yields a characterization that is essentially the same as it is for large.
Constitutional Adjudication in the World Trade Organization

Although a court, as a judicial organ, usually fulfils its mission by resolving specific disputes brought to it, it occasionally goes beyond this simple dispute-resolving function and more actively engages in building policies which define, and "constitute," the very polity to which the court belongs, as was seen in Brown v. Board of Education. If this "constitutional adjudication" is an integral function of any domestic high court, could (and should) an international tribunal, in particular the World Trade Organization (WTO) tribunal, also play such a distinctive role? This paper contends that the WTO tribunal has in fact assumed such role by having recently struck down a hoary antidumping practice called "zeroing" which tends to inflate dumping margins and thus is a central vehicle for contingent protection embedded in the antidumping mechanism. The paper observes that the recent proliferation of antidumping measures as a new protectionist instrument has motivated the AB's hermeneutical departure from the past interpretation which had endorsed the practice. This, it argues, is a "constitutional" turn of the WTO which a positivist, inter-governmental mode of thinking, as is prevalent in other international organizations such as the United Nations, cannot fully expound. Critically, this turn originates from bold ideas which envision, and thus "constitute," new institutional meaning and possibilities within the WTO. In other words, the AB's exegesis is anchored firmly by a discernible purpose of cabining trade distortive/restrictive consequences from the use of zeroing which have long been left unchecked. Finally, WTO members, the paper maintains, must preserve the anti-zeroing jurisprudence as constitutional norms in the absence of extraordinary circumstances tantamount to a constitutional amendment. In particular, it must not be a subject of political bargaining in the trade negotiation.
Convention, Social Order, and the Two Coordinations

The word “coordination” has two meanings, and thesemeanings are often conflated. One meaning, associated with ThomasSchelling, is seen in situations like choosing whether to driveon the left or the right; the drivers must coordinate to eachother's behavior. The other meaning, associated with FriedrichHayek, means that a concatenation of activities is arranged soas to produce good results. Along with the Schelling sense ofcoordination comes the notion of convention, such as drivingon the right. Some conventions are consciously designed; othersemerge without design (or are “emergent”). Along with the Hayeksense of coordination comes the notion of social order. Somesocial orders, such as the skeleton of activities within thefirm or within the hypothetical socialist economy, are consciouslyplanned. Other social orders, such as the catallaxy of the freesociety, function without central planning (or are “spontaneous”).Distinguishing between the two coordinations (and, in parallelfashion, between convention and social order) clarifies thinkingand resolves some confusions that have arisen in discussionsof “coordination” and “spontaneous order.” The key distinctionsare discussed in the context of the thought of, on the one hand,Menger, Schelling, David Lewis, and the recent path-dependencetheorists, and, on the other hand, Smith, Hayek, Polanyi, Coase,and the modern Austrian economists. The paper concludes witha typology that encompasses the several distinctions.
Property Rights and Wireless License Values

Abstract While extending the scope of spectrum property rights promotes efficiency, such reforms are often deterred by equity concerns. Theoretically, however, the windfalls may be negative. Relaxing license restrictions may increase profits by allowing enhanced productivity, yet liberalization across a class of licensees can reduce the expected profits by increasing competitiveness. This article examines license value changes for regimes that decisively shift toward private property rights in radio spectrum by analyzing the average prices paid in international cellular phone license auctions during 1995–2001. This unique data set encompasses 1,365 licenses assigned by competitive bidding in 38 auctions held in 24 countries. Licenses awarded by regimes with more expansive spectrum property rights generated winning bids that were 61 percent lower, adjusting for other factors. This evidence reverses the equity argument against liberalization over the policy margin studied and is consistent with Coase’s view...
Strong law of large numbers for the interface in ballistic deposition

Abstract We prove a hydrodynamic limit for ballistic deposition on a multidimensional integer lattice. In this growth model particles rain down at random and stick to the growing cluster at the first point of contact. The theorem is that if the initial random interface converges to a deterministic macroscopic function, then at later times the height of the scaled interface converges to the viscosity solution of a Hamilton–Jacobi equation. The proof idea is to decompose the interface into the shapes that grow from individual seeds of the initial interface. This decomposition converges to a variational formula that defines viscosity solutions of the macrosopic equation. The technical side of the proof involves subadditive methods and large deviation bounds for related first-passage percolation processes.
Free Trade Areas with Politically Active Oligopolies

I evaluate in this paper the impact of Free-Trade Areas (FTAs) on the world trade system using an oligopolistic-political-economy model that treats the member countries’ external tariffs as endogenously determined. In this context, I find that FTAs are likely a “building block” of the multilateral system. This conclusion is based, first, on the finding that FTAs induce the member governments to lower their external tariffs, and to do so deeply enough to generate trade creation between members and outsiders – thus benefiting the latter. The FTAs members need not gain, but since their governments, in spite of their political preferences, endorse only welfare-improving FTAs, they also gain with the ratified arrangements. Finally, I find also that FTAs make the support for an efficient multilateral liberalization more likely, as they reduce the role of special interests criteria on the governments’ trade regimes decisions.
Planetary Nebulae as Probes of Stellar Evolution and Populations

Planetary Nebulae (PNe) have been used satisfactory to test the effects of stellar evolution on the Galactic chemical environment. Moreover, a link exists between nebular morphology and stellar populations and evolution. We present the latest results on Galactic PN morphology, and an extension to a distance unbiased and homogeneous sample of Large Magellanic Cloud PNe. We show that PNe and their morphology may be successfully used as probes of stellar evolution and populations
Multi-pulse interferometric frequency-resolved optical gating Real-time phase-sensitive imaging of ultrafast dynamics

We demonstrate a powerful new tool for real-time imaging of ultrafast phase shifts without computation. Additionally, this technique can, with interferogram analysis and iterative phase retrieval, recover the intensity and phase of three pulses in a single shot. Results of ultrafast time-resolved coherent spectroscopy of cross-phase modulation in fused silica and ultrafast ionization fronts are reported.
Some experiences with process control languages

The past years have seen a change of emphasis in process control languages. Most of the software for the early process automation systems developed at the General Electric Process Computer Department was implemented in assembly language. Today, FORTRAN is being used at least partially in many of our applications. Some of our experiences in this area are briefly reviewed and evaluated and an opinion is expressed on what direction future efforts might be expected to take.
Computing optimal security strategies for interdependent assets

We introduce a novel framework for computing optimal randomized security policies in networked domains which extends previous approaches in several ways. First, we extend previous linear programming techniques for Stackelberg security games to incorporate benefits and costs of arbitrary security configurations on individual assets. Second, we offer a principled model of failure cascades that allows us to capture both the direct and indirect value of assets, and extend this model to capture uncertainty about the structure of the interdependency network. Third, we extend the linear programming formulation to account for exogenous (random) failures in addition to targeted attacks. The goal of our work is two-fold. First, we aim to develop techniques for computing optimal security strategies in realistic settings involving interdependent security. To this end, we evaluate the value of our technical contributions in comparison with previous approaches, and show that our approach yields much better defense policies and scales to realistic graphs. Second, our computational framework enables us to attain theoretical insights about security on networks. As an example, we study how allowing security to be endogenous impacts the relative resilience of different network topologies.
X-ray spectra and atmospheric structures of bursting neutron stars

Atmospheric structures and emitted X-ray spectra of bursting neutron stars are investigated. Theoretical curves are fitted to observational ones on the color temperature vs. luminosity diagram and two relations among mass, radius, and distance of the bursters are obtained. The fit of the theoretical curve to observations is statistically acceptable. Two possible sets of mass, radius, and distance to the X-ray bursts source MXB 1636-536 are derived, taking into account absorption lines at 4.1 keV, theoretical mass-radius relations of neutron star models, and the distance to the Galactic center. If the absorption line is due to Cr XX III, then M = 1.7-2.0 solar masses, R = 11-12 km, and d = 6.3-6.7 kpc, and if it is due to Fe XXV, then M = 1.8-2.1 solar masses, R = 8-10 km, and d = 5.8-6,4 kpc. The distance to the Galactic center is almost the same as that to MXB 1636-536.
[Which way is up? Policies and procedures for surgeons and pathologists regarding resection specimens of thymic malignancy].

Thymic malignancies are relatively uncommon, which mandates that the experience from many different institutions be combined to achieve a better understanding of the disease. Nevertheless, this is hampered by many ambiguities in how results are reported and interpreted. This problem is aggravated by the fact that smaller institutions often encounter these tumors only sporadically. A prerequisite to interinstitutional collaboration is a common language and consistency in the definition of findings (e.g., whether a complete resection was accomplished or not). This article summarizes the policies adopted by the International Thymic Malignancy Interest Group (ITMIG) regarding handling of a resection specimen by the surgeon and pathologist and reporting of the surgical and pathologic findings. These policies are based as much as possible on reported evidence, but this is lacking or limited in many areas. Nevertheless, adoption of a consistent approach is crucial to conduct valid studies moving forward that can clarify areas of uncertainty. This publication addresses only how to handle and process the tissue specimen at the time of a resection. It does not address handling and interpretation of biopsies or cytologic specimens, which is an important topic that is addressed in a separate publication.1 This article is limited to an open resection (by sternotomy). Although other approaches are sometimes used (e.g., thoracoscopy), the issues involved are also covered in another publication.2 Furthermore, this article is written with the assumption that resection of a thymoma involves a complete thymectomy along with any adjacent structures that may be involved and that the goal is a complete (R0) resection (i.e., not debulking).
Primordial Black Holes and Hot Matter

Microscopic black holes explode with their temperature varying inversely as their mass. Such explosions would lead to the highest temperatures in the present universe, all the way to the Planck energy. The possibility that a quasi-stationary shell of hot matter surrounds these black holes has recently been proposed and studied with relativistic Boltzmann transport equations and with relativistic viscous fluid dynamics. For example, a black hole with a mass of 1010 g has a Hawking temperature of 1 TeV, a Schwarszchild radius of 1.6 x 10-5 frn, a luminosity of 7 x 1027 erg/s, and has less than 8 minutes to live. It is an outstanding theoretical challenge to describe the conditions exterior to such microscopic black holes and a great challenge to finally detect them in the new millennium.
Indexed Predicate Discovery for Unbounded System Verification

Predicate abstraction has been proved effective for verifying several infinite-state systems. In predicate abstraction, an abstract system is automatically constructed given a set of predicates. Predicate abstraction coupled with automatic predicate discovery provides for a completely automatic verification scheme. For systems with unbounded integer state variables (e.g. software), counterexample guided predicate discovery has been successful in identifying the necessary predicates.
Graphical Methods for Efficient Likelihood Inference in Gaussian Covariance Models

In graphical modelling, a bi-directed graph encodes marginal independences among random variables that are identified with the vertices of the graph. We show how to transform a bi-directed graph into a maximal ancestral graph that (i) represents the same independence structure as the original bi-directed graph, and (ii) minimizes the number of arrowheads among all ancestral graphs satisfying (i). Here the number of arrowheads of an ancestral graph is the number of directed edges plus twice the number of bi-directed edges. In Gaussian models, this construction can be used for more efficient iterative maximization of the likelihood function and to determine when maximum likelihood estimates are equal to empirical counterparts.
African Legal Studies: A Survey of the Field and the Role of the United States

In the United States lawyers have been slow starters in the field of African studies. While American anthropologists and sociologists-and in more recent years, political scientists and economists-have been prolific in African research,' their legal colleagues have, with few exceptions,2 remained silent. Perhaps this is attributable in some degree to the natural conservatism of the breed, or-as the less charitable may aver-to legal parochialism. More probably it is due to the pressing claims on time and money which are made in American law schools by less exotic and, it would seem, more immediately practical subjects; then, too, it must be borne in mind that the freedom of the United States from colonial commitments in Africa removed one of the incentives which induced lawyers in countries like Britain or France to devote themselves to this field. But perhaps the main reason for the late entry of American lawyers into this area is the fact that it is only in very recent years, with the upsurge of independence throughout Africa, that knowledge of African legal systems, and of their potential development, has become essential for the effective conduct of international relations and trade. The recently won freedom of African states has generated a new vitality, and has brought into focus new problems of world-wide importance. But despite the comparative novelty in America of African legal studies, it would be a mistake to conclude that no work has been done in this field. While it is perhaps true that lawyers, as a class, have tended to be less prolific and, possibly, less influential in African studies than their colleagues in anthropology, sociology, political science, and history,3 they have not in the past neglected African problems
The Census Taker's Hat

If the observable universe really is a hologram, then of what sort? Is it rich enough to keep track of an eternally inflating multiverse? What physical and mathematical principles underlie it? Is the hologram a lower dimensional quantum field theory, and if so, how many dimensions are explicit, and how many 'emerge?' Does the Holographic description provide clues for defining a probability measure on the Landscape? The purpose of this lecture is first, to briefly review a proposal for a holographic cosmology by Freivogel, Sekino, Susskind, and Yeh (FSSY), and then to develop a physical interpretation in terms of a 'Cosmic Census Taker:' an idea introduced in reference [1]. The mathematical structure--a hybrid of the Wheeler DeWitt formalism and holography--is a boundary 'Liouville' field theory, whose UV/IR duality is closely related to the time evolution of the Census Taker's observations. That time evolution is represented by the renormalization-group flow of the Liouville theory. Although quite general, the Census Taker idea was originally introduced in \cite{shenker}, for the purpose of counting bubbles that collide with the Census Taker's bubble. The 'Persistence of Memory' phenomenon discovered by Garriga, Guth, and Vilenkin, has a natural RG interpretation, as does slow roll inflation. The RG flow and the related C-theorem are closely connected with generalized entropy bounds.
The Determinants of Quality Specialization

A growing literature suggests that high-income countries export high-quality goods. Two hypotheses may explain such specialization, with dierent implications for welfare, inequality, and trade policy. Fajgelbaum, Grossman, and Helpman (JPE 2011) formalize the Linder (1961) conjecture that home demand determines the pattern of specialization and therefore predict that high-income locations export high-quality products. The factor-proportions model also predicts that skill-abundant, high-income locations export skill-intensive, high-quality products (Schott, QJE 2004). Prior empirical evidence does not separate these explanations. I develop a model that nests both hypotheses and employ microdata on US manufacturing plants’ shipments and factor inputs to quantify the two mechanisms’ roles in quality specialization across US cities. Home-market demand explains at least as much of the relationship between income and quality as dierences in factor usage.
Production of Tungsten-188 and Osmium-194 in a Nuclear Reactor for New Clinical Generators

Rhenium-188 and iridium-194 are potential candidates for radioimmunotherapy with monoclonal antibodies directed against tumor-associated antigens. Both nuclei are short-lived and decay by high energy β- emission. In addition, both nuclei emit γ-rays with energy suitable for imaging. An important characteristic is availability of 188Re and 194Ir from decay of reactor-produced parents (188W and 194Os, respectively) in convenient generator systems. The 188W and 194Os are produced by double neutron capture of 186W and 192Os, respectively. The large scale production yields of 188W in several nuclear reactors will be presented. We also report a new measurement for the cross-section of 193Os(n,γ)194Os reaction and discuss the feasibility of producing sufficient quantities of 194Os.
Average Age at Death

This article describes the fallacy of “average age at death”, a common misuse of age data for summarizing mortality experience and estimating life expectancy. An example is presented to illustrate this fallacy. Considerations that should be taken into account for more accurate analysis of these data are reviewed. Keywords: age; age distribution; death; fallacy; life expectancy; mean (age); mortality; risk of death
Togo growth diagnostics

This paper starts by analyzing past growth trends and sources of growth in Togo, as well as the structure of the economic actors in the country. The second part explores the current binding constraints to rapid and sustainable growth. For increased international competitiveness and growth, Togo will need to raise efforts to streamline its costly and cumbersome business procedures. However, for this to have a sizable impact, Togo must prove to potential investors that political stability is permanent and that corruption, poor budget execution and mismanagement of state owned enterprises belongs to the past. As a result of the new government's reform agenda and the return of international aid, a window of opportunities for high returns to the still limited public investments has opened up. This is especially true in infrastructure and connectivity services, which would not only take advantage of Togo's geographical location as a regional hub, but also make growth in Togo more inclusive. And as economic opportunities arise for the private sector, there is a need to restructure the banking sector, which has already started, to smooth distortions in the credit market. Promising sectors within agriculture that are vital to economic growth, employment opportunities, and poverty reduction remain important, but will need to overcome a number of coordination failures. Not least due to the history of government interventions causing economic distortions, the government must allow for a stronger role for private operators and encourage it wherever possible. Finally, although education does not exhibit constraints to economic activity in Togo today, it is of importance to improve the quality of education, not least to profit from and catalyze the opportunities related to Togo's potential as a regional hub.
Can Voluntary Programs Resolve China's Environmental Crisis? An Analysis of ISO 14001 Certification in a Sample of Chinese Firms

I study the determinants of ISO 14001 certification in a sample of manufacturing firms in China as well as the effect of ISO 14001 certification on firm environmental performance. Results indicate that ISO 14001 plays an important role in signaling the firm's environmental technology to environmentally conscious customers. ISO 14001 also appears to improve firm environmental performance, even after controlling for endogeneity between performance and certification.
Characteristics of Low-Income Households With Very Low Food Security: An Analysis of the USDA GPRA Food Security Indicator

This bulletin describes characteristics of low-income households that had very low food security in 2005. The U.S. Department of Agriculture monitors the food security of low-income households to assess how effectively the Government's domestic nutrition assistance programs meet the needs of their target populations. In 2005, 12.6 percent of low-income households - those with annual incomes less than 130 percent of the Federal poverty line - had very low food security. USDA seeks to reduce that prevalence rate as one of its strategic planning goals established under the Government Performance and Results Act (GPRA). To achieve the USDA food security target, the food security of households with incomes that are less than 130 percent of the poverty line (less than $26,000 annual income for a family of two adults and two children) will need to surpass the current level of food security of households with incomes in the range of 130 to 150 percent of the poverty line ($26,000 to $30,000).
Statistical analysis of backtracking on inconsistent CSPs

We analyze the distribution of computational effort required by backtracking algorithms on unsatisfiable CSPs, using analogies with reliability models, where lifetime of a specimen before failure corresponds to the runtime of backtracking on unsatisfiable CSPs. We extend the results of [7] by showing empirically that the lognormal distribution is a good approximation of the backtracking effort on unsolvable CSPs not only at the 50% satisfiable point, but in a relatively wide region. We also show how the law of proportionate effect [9] commonly used to derive the lognormal distribution can be applied to modeling the number of nodes expanded in a search tree. Moreover, for certain intervals of C/N, where N is the number of variables, and C is the number of constraints, the parameters of the corresponding lognormal distribution can be approximated by the linear lognormal model [11] where mean log(deadends) is linear in C/N, and variance of log(deadends) is close to constant. The linear lognormal model allows us to extrapolate the results from a relativelyeasy overconstrained region to the hard critically constrained region and, in particular, to use more efficient strategies for testing backtracking algorithms. This work was partially supported by NSF grant IRI-9157636, Air Force Office of Scientific Research grant AFOSR 900136, Rockwell Micro grant 22147, and UC Micro grant 96-012.
An efficient algorithm to calculate intrinsic thermoelectric parameters based on Landauer approach

The Landauer approach provides a conceptually simple way to calculate the intrinsic thermoelectric (TE) parameters of materials from the ballistic to the diffusive transport regime. The approach relies on the calculation of the number of propagating modes and the mean free path for each mode. The modes are calculated from the energy dispersion (E(k)) of the materials, which require heavy computation and are often restricted to energy relations on sparse momentum (k) grids. Here an efficient method to calculate the distribution of modes (DOM) from a given E(k) relationship is presented. The two main features of this algorithm are: (i) its ability to work on sparse dispersion data, and (ii) creation of an energy grid for the DOM that is almost independent of the dispersion data therefore allowing for efficient and fast calculation of TE parameters. The effect of K-grid sparsity on the compute time for DOM and on the sensitivity of the calculated TE results are provided. The algorithm calculates the TE parameters within 5% accuracy when the K-grid sparsity is increased up to 60% for all the dimensions (3D, 2D and 1D). The time taken for the DOM calculation is strongly influenced by the transverse K density (K perpendicular to transport direction) but is almost independent of the transport K density (along the transport direction). The DOM and TE results from the algorithm are bench-marked with, (i) analytical calculations for parabolic bands, and (ii) realistic electronic and phonon results for Bi2Te3.
Polarizabilities of intermediate sized lithium clusters from density-functional theory

We present a detailed investigation of static dipole polarizability of lithium clusters containing up to 22 atoms. We first build a database of lithium clusters by optimizing several candidate structures for the ground state geometry for each size. The full polarizability tensor is determined for about 5-6 isomers of each cluster size using the finite-field method. All calculations are performed using large Gaussian basis sets, and within the generalized gradient approximation to the density functional theory, as implemented in the NRLMOL suite of codes. The average polarizability per atom varies from 11 to 9 AAA, within the 8-22 size range and show smoother decrease with increase in cluster size than the experimental values. While the average polarizability exhibits a relatively weak dependence on cluster conformation, significant changes in the degree of anisotropy of the polarizability tensor are observed. Interestingly, in addition to the expected even odd (0 and 1 $μ_B$) magnetic states, our results show several cases where clusters with an odd number of Li atoms exhibit elevated spin states (e.g. 3 $μ_B$).
Policy Rules and External Shocks

The decade since 1990 has been a period of innovation in monetary policy. Around the world, many countries have adopted inflation targeting as their basic policy framework. Different countries have tried different techniques for achieving inflatio targets, such as different choices of policy instruments.
Contextual Semantic: A Context-aware Approach for Semantic Web Based Data Extraction from Scientific Articles

The paper explores whether the semantic context is good enough to cope with ever increasing number of available resources in different repositories including the web. Here a problem of identifying authors of scientific papers is used as an example. A set of problem still do arise in case we apply exclusively the semantic context. Fortunately contextual semantic can be used to derive more information required to separate ambiguous cases. Semantic tags, well-structured documents and available databases of articles do provide a possibility to be more context-aware. Under the context we use co-authors names, references and headers to extract key-words and identify the subject. The real complexity of the considering problem comes from the dynamical behaviour of authors as they can change the topic of the research in the next paper. As the final judge the paper proposes applying words usage patterns analysis. Final the contextual intelligence engine is described.
Can emergency physicians diagnose and correctly classify diastolic dysfunction using bedside echocardiography

Abstract Objectives The goal of this study was to determine if emergency physicians (EPs) can correctly perform a bedside diastology examination (DE) and correctly grade the level of diastolic function with minimal additional training in echocardiography beyond what is learned in residency. We hypothesize that EPs will be accurate at detecting and grading diastolic dysfunction (DD) when compared to a criterion standard interpretation by a cardiologist. Methods We conducted a prospective, observational study on a convenience sample of adult patients who presented to an urban emergency department with a chief concern of dyspnea. All patients had a bedside echocardiogram, including a DE, performed by an EP-sonographer who had 3 hours of didactic and hands-on echocardiography training with a cardiologist. The DE was interpreted as normal, grade 1 to 3 if DD was present, or indeterminate, all based on predefined criteria. This interpretation was compared to that of a cardiologist who was blinded to the EPs' interpretations. Results We enrolled 62 patients; 52% had DD. Using the cardiology interpretation as the criterion standard, the sensitivity and specificity of the EP-performed DE to identify clinically significant diastolic function were 92% (95% confidence interval [CI], 60-100) and 69% (95% CI, 50-83), respectively. Agreement between EPs and cardiology on grade of DD was assessed using κ and weighted κ : κ = 0.44 (95% CI, 0.29-0.59) and weighted κ = 0.52 (95% CI, 0.38-0.67). Overall, EPs rated 27% of DEs as indeterminate, compared with only 15% by cardiology. For DEs where both EPs and cardiology attempted an interpretation (indeterminates excluded) κ = 0.45 (95% CI, 0.26 to 0.65) and weighted κ = 0.54 (95% CI, 0.36-0.72). Conclusion After limited diastology-specific training, EPs are able to accurately identify clinically significant DD. However, correct grading of DD, when compared to a cardiologist, was only moderate, at best. Our results suggest that further training is necessary for EPs to achieve expertise in grading DD.
Capability Stretching in Product Innovation

Product innovation is conventionally treated as a mechanism for organizations to renew their product portfolios. In this paper, we suggest that product innovation not only enables organizations to introduce new products to the market but also challenges organizations to renew their technological capabilities. Capability stretching is the degree to which an organization extends its technological capabilities to bridge the gap between what it has already known and what the development of a new product requires it to know. Capability stretching can be challenging because it involves the acquisition and assimilation of new and distant knowledge. Drawing on a longitudinal study of product introductions in the workstation industry, we find that capability stretching reduces the chance of new product survival. Furthermore, we also find that organizational boundaries moderate the negative relationship between capability stretching and product survival: Vertical integration exacerbates this negative relationship, ...
Public Employment Services, and Activation Policies

One of the responses to new challenges in the labor market has been the development and expansion of employment services and active labor market policies based on activation principles. The objective of this study is to document and review international experiences, predominantly from selected emerging market economies and developing countries, with the design and implementation of activation programs, provided by Public Employment Services, through the prism of incentives and sanctions. Employment promotion legislation from the reviewed countries is a major source of information. Participation of beneficiaries in relevant services and programs is also analyzed. The study finds that the countries use a variety of instruments, be it specific employment services, active labor market programs, or benefit and other sanctions, to 'activate' jobseekers with an aim to encourage them to become more active in their efforts to find work and/or improve their employability. In practice, the activation policies vary considerably across countries.
Deciding Consistency of Databases Containing Defeasible and Strict Information

Abstract We propose a norm of consistency for a mixed set of defeasible and strict sentences, based on a probabilistic semantics. This norm establishes a clear distinction between knowledge bases depicting exceptions and those containing outright contradictions. We then define a notion of entailment based also on probabilistic considerations and provide a characterization of the relation between consistency and entailment.
Family Planning Policy in China: Measurement and Impact on Fertility

The extent to which China's family planning policy has driven its fertility transition over the past decades is debatable. The disagreement is partly sourced from the different ways of measuring the policy. Most existing measures, constructed on the policy history, generally, do not include complete secular and cross-sectional policy variations, fail to heterogeneously reflect people's exposure to the policy, and often suffer from endogeneity. This paper reviews the entire history of China's family planning policy and accordingly, proposes a new policy measure that integrates the policy variations more completely, heterogeneously, and exogenously by using the cross-sectional data of the China Health and Nutrition Survey. The new measure estimates the effect of policy on fertility and generates negative regression coefficients that well reproduce the history. As for the contribution of the policy to fertility transition, the measure explains a sizable level shift of fertility for major cohorts, but only accounts for a small portion of the fertility decline over generations. In addition, a more-educated woman, a woman residing in a better-developed coastal province, or a woman whose first child is a son tends to desire fewer children and thus, receives lighter pressure from the policy. Other than fertility, a woman would delay her marriage in response to the policy, particularly when it is strongly enforced. Finally, the paper shows that using an incomplete measure could systematically underestimate the effect of policy on fertility and adopting an endogenous measure or a measure lacking heterogeneity could even produce a positive effect of the policy.
Cross-Sectional Dispersion of Firm Valuations and Expected Stock Returns

This paper develops two competing hypotheses for the relation between the cross-sectional standard deviation of logarithmic firm fundamental-to-price ratios (``dispersion'') and expected aggregate returns. In models with fully rational beliefs, greater dispersion indicates greater risk and higher expected aggregate returns. In models with investor overconfidence, greater dispersion indicates greater mispricing and lower expected aggregate returns. Consistent with the behavioral models, the results show that (1) measures of dispersion are negatively related to subsequent market excess returns, (2) this negative relation is more pronounced among riskier firms, and (3) dispersion is positively related to aggregate trading volume, idiosyncratic volatility, and investor sentiment, and increases after good past market performance.
The Association between Information Technology Investments and Audit Risk

ABSTRACT: Advances in information technology (IT) have changed the way that companies conduct business, prepare their financial statements, and have their financial statements audited. On one hand, IT decreases audit risk by improving operation and internal control effectiveness, which may decrease inherent and internal control risk. On the other hand, the complexity of IT introduces unconventional risks for companies and their auditors, especially by creating challenges for auditors when auditing the effectiveness of internal controls and detecting accounting irregularities. Thus, the relationship between clients' IT investments and audit risk deserves research attention. Using IT data of U.S. firms from 2000 to 2009, we find that IT investments are positively related to audit fees (and abnormal audit fees), the probability of auditors' issuance of a going-concern opinion, and the likelihood of auditors' Type II errors. Furthermore, we find that auditor tenure moderates the relationship between IT invest...