cssi/SciSciGPT-SciSciNet huggingface dataset:
An Incremental Weighted Least Squares Approach to Surface Lights Fields

An Image-Based Rendering (IBR) approach to appearance modelling enables the capture of a wide variety of real physical surfaces with complex reflectance behaviour. The challenges with this approach are handling the large amount of data, rendering the data efficiently, and previewing the model as it is being constructed. In this paper, we introduce the Incremental Weighted Least Squares approach to the representation and rendering of spatially and directionally varying illumination. Each surface patch consists of a set of Weighted Least Squares (WLS) node centers, which are low-degree polynomial representations of the anisotropic exitant radiance. During rendering, the representations are combined in a non-linear fashion to generate a full reconstruction of the exitant radiance. The rendering algorithm is fast, efficient, and implemented entirely on the GPU. The construction algorithm is incremental, which means that images are processed as they arrive instead of in the traditional batch fashion. This human-in-the-loop process enables the user to preview the model as it is being constructed and to adapt to over-sampling and under-sampling of the surface appearance.
ACCUMULATION OF CREEP DAMAGE UNDER VARYING TEMPERATURE CONDITIONS

ABSTRACT A method was developed for calculating the creep damage accumulated in a material subjected to varying temperatures under constant stress. To the extent that the creep behavior of the material may be described with the Larson-Miller parameter, and creep damage accumulates according to the life-fraction rule, the method is exact. Specific expressions were derived for a number of cases in which the temperature rises monotonically and also for cases in which the temperature cycles repetitively.
Gender-targeted conditional cash transfers : enrollment, spillover effects and instructional quality

This paper considers the effects of a gender-targeted conditional cash transfer program for girls in classes 6 to 8. It finds that the program is successful in increasing the enrollment of girls in classes 6 to 8 as intended. It also finds evidence to suggest that the program generated positive spillover effects on the enrollment of boys. This success does, however, appear to be poised to come at a cost. The student-teacher ratio in treated districts is also climbing. This suggests that in the absence of active steps to address these increasing student-teacher ratios, instructional quality is likely to suffer. The success of the program appears to be driven by enrollment increases in urban schools. This suggests the need for a reassessment of the targeting criteria in rural schools.
Notice of Retraction Notice of Retraction Success factors for meeting operational goals

Businesses with the best product-development track records stand apart from their less-successful peers in crucial ways. We found - after surveying more than 300 employees at 28 companies across North America and Europe - that businesses with the best R&D performance do well in Customer Insights, Concept Development, PD Execution, and Risk Management.
Radioactive Tracers in Hydrometeorology

Atmospheric motion is studied with aid of radioactive tracers; they can be used to track path of masses of water in atmosphere; most promising tracer seems to be tritium but large number of sources of tritium complicates its application to hydrological problems.
Accelerated Life Testing

Accelerated testing is a set of methods that attempts to replicate and predict the quantitative effect on product life of what are assumed to be the most important degradation mechanisms determining product life in actual service. In all accelerated testing approaches, one or more physical degradation methods are applied to promote failure. The history and limitations of accelerated testing and mathematical tools for modeling product lifetime as a function of acceleration mechanisms are discussed. Keywords: accelerated lifetime; life stress relationship models; arrhenius; inverse power law; voltage models; MTBF ; proportional hazards; HAST
Synthesis and Application of Palladium Precatalysts that Accommodate Extremely Bulky Di-tert-butylphosphino Biaryl Ligands

A series of palladacyclic precatalysts that incorporate electron-rich di-tert-butylphosphino biaryl ligands is reported. These precatalysts are easily prepared, and their use provides a general means of employing bulky ligands in palladium-catalyzed cross-coupling reactions. The application of these palladium sources to various C–N and C–O bond-forming processes is also described.
ENCOURAGING FARMERS TO PRODUCE ENVIRONMENTAL BENEFITS FROM AGRICULTURE

Farmers produce many things in abundance for which they receive income, including food, feed, fiber and fuel. Similarly, farmers generate environmental benefits such as improved water quality by reducing soil and nutrient loss and improved wildlife habitat by managing their operation in certain ways. Unfortunately, most farmers receive limited or no compensation for these positive externalities they produce. If we wish to encourage more of these positive externalities, policies need to be established and implemented that compensate producers for the benefits society receives from specific farming practices. This research examined how production practices that provide environmental benefits would affect water quality (nutrient and sediment loss), fisheries populations, and farm income in two distinct study areas in Minnesota. We developed a computer simulation model to examine the relationship between agricultural practices, water quality, fish communities, and net farm income within two small watersheds. Our analyses focused on a coolwater stream, the Wells Creek watershed in southeastern Minnesota, and a warmwater stream, a sub-watershed of the Chippewa River in western Minnesota. We used the Agricultural Drainage and Pesticide Transport (ADAPT) model in relation to land use to calculate in-stream suspended sediment concentrations using estimates of sediment delivery, runoff, baseflow and stream bank erosion, and quantified the effects of suspended sediment exposure on fish communities. Our focus was to estimate how agricultural Best Management Practices (BMPs ? conservation tillage and nutrient management implemented on all cropland, and 100 foot grass buffers along streams) would affect stream fish communities and net farm income, with reference to current conditions. We found a decrease in "lethal" concentrations of suspended sediment on fish in Wells Creek watershed with an increase in conservation tillage, riparian buffers, and permanent vegetative cover. However, land use change in the Chippewa River watershed did not significantly decrease the effects of suspended sediment on the fish community. This difference between watersheds is likely due to differential tolerance to suspended sediment between coolwater and warmwater fish communities and differences in topography, runoff and bank erosion between the two streams.
Schools and Housing Markets: An Examination of School Segregation and Performance in Connecticut

This paper estimates a dynamic model of price level, school performance, and school racial and ethnic composition in the State of Connecticut. The paper finds that increasing minority representation in a Labor Market Area reinforces the existing pattern of school segregation. Changes in segregation appear to be influenced by demographic trends in urban areas and by the labour market factors that determine those trends. There is no evidence, however, to suggest that this process affects housing prices; rather, the housing market appears to adjust relatively quickly.
Oblivious Transfer in the Bounded Storage Model

Building on a previous important work of Cachin, CrEpeau, and Marcil [15], we present a provably secure and more efficient protocol for (2 1)-Oblivious Transfer with a storage-bounded receiver. A public random string of n bits long is employed, and the protocol is secure against any receiver who can store γn bits, γ < 1. Our work improves the work of CCM [15] in two ways. First, the CCM protocol requires the sender and receiver to store O(nc) bits, c ∼ 2/3. We give a similar but more efficient protocol that just requires the sender and receiver to store O(√kn) bits, where k is a security parameter. Second, the basic CCM Protocol was proved in [15] to guarantee that a dishonest receiver who can store O(n) bits succeeds with probability at most O(n-d), d ∼ 1/3, although repitition of the protocol can make this probability of cheating exponentially small [20]. Combining the methodologies of [24] and [15], we prove that in our protocol, a dishonest storage-bounded receiver succeeds with probability only 2-O(k), without repitition of the protocol. Our results answer an open problem raised by CCM in the affirmative.
Algorithms for Optimized Node Arrangements in ShuffleNet Based Multihop Lightwave Networks

The capabilities of emerging optical technology, viz. dense wavelength division multiplexing (WDM) and tunable optical transmitters and receivers (transceivers) can be exploited to construct lightwave networks, as follows. First, by employing WDM, the huge optical bandwidth (in the order of Terahertz) is partitioned into a number of smaller capacity channels (in the order of Gigahertz) which are compatible with the electronic interface speeds. Second, each node with its tunable transmitter(s) and receiver(s) can access a subset of the available channels by tuning its transceivers to the appropriate wavelengths. Now, the system can be configured as a broadcast-and-select network in which all of the inputs from various nodes are combined in a star coupler and the mixed optical information is broadcast to all the outputs. Thus, a multitude of virtual network configurations can be superimposed over any given physical network topology.The goal of this study is to exploit the aforementioned capabilities of lightwave technology in order to construct optimized regular multihop networks when the traffic flow among the network nodes is asymmetric. The specific problem addressed here is as follows: Given that the network nodes must be connected in a regular interconnection pattern and that the node positions in the regular network can be adjusted by properly tuning their (optical) transceivers, what is the best node placement in a given regular topology? We have chosen ShuffleNet based regular structure as the model of our network topology. ShuffleNet can interconnect a large number of nodes with a small number of transceivers per node such that information from a source can reach its destination in a small number of hops. However, finding the optimal node placement is a computationally hard problem. So, we formulate efficient heuristic algorithms to design optimized ShuffieNet structures for a given traffic matrix. Also, a scheme is developed to dynamically rearrange the logical node positions to a new optimized configuration, within the ShuffleNet framework, when the pattern of offered load changes.
Past US Studies and Developments for Planetary Rovers

無人探査宇宙船の月や火星への着陸の後に続く論理的なステップとして, 移動ロボットを上陸させることが長い間, 当然と考えられてきた.しかし, アメリカの宇宙計画でおきたことはこの順序に沿ったものとなっていない.本報では何がなぜ起こったかをふり返り, ミッションの結果, 技術上のアプローチ, そして将来の可能性について要約する.なお, 本シンポジウムの他の論文でより詳しく述べられている話題は簡単に触れるに留める.アメリカの月探査ローバの研究は, 三つの段階にわけられる.まず, 1960年代初め, 月に質量約50 [kg] のローバを送り込むため, 「サーベイヤー」月着陸船の容量を確保しようとした.1964年の初頭にいくつかの装置が製作・試験されたが, いずれも月へは行かなかった.続いて, 有人の400 [kg] の短距離用ローバが開発された.それらのうちの3台がアポロ15号, 16号, 17号の飛行ミッションの一部として1971年と1972年に月で運転された.これらのアポロの成功に引き続いて, 200～300キログラムクラスの自動またはデュアルモード (人間搭乗・無人) のローバと, 人間を長期の踏査に連れ出すことができる数トンの移動気密室となるローバの2種の継続機を提供する試みがなされた.しかし, 1970年代のソビエトとアメリカの月開発の終結によって, どちらの提案も実現に致らなかった.これらの月開発と並行してアメリカでは火星探査の長期技術プログラムが, ある時はプリプロジェクト状態に近付き, またある時は消えかかりながらも完全に放棄されることなく続けられてきた.その結果, 今日, 私達は数年のうちに実現可能な段階にある広範な月や火星の探査ミッション構想をもっている.しかし, 今日の資金的な抑制の下ではこれらの十分に研究された大規模ミッションのコンセプトはいずれも具現化しないであろう.そこで私達はこれよりはるかに小さなローバの開発に転向した.この開発には, 今日の小型化技術をローバ本体のみでなく, 搭載する計測器類にまで応用している.本シンポジウムに発表されている他の論文も, この研究の状況を述べたものである.
Bumpy Rides: School-to-work Transitions in South Africa

Re-enrollment in school following a period of dropout is a common feature of school-to-work transitions, but has been largely ignored in the literature on sequential schooling choice. I quantify the importance of the option to re-enroll in school-to-work transitions in South Africa. I estimate a model of sequential schooling choice using a panel that contains the entire schooling and labor market histories of sampled youth. The model incorporates Bayesian learning about academic ability and the probability of employment in response to outcomes from past choices, with updated beliefs influencing the expected returns to human capital investment and labor market participation. I conduct a policy simulation under which re-enrollment prior to high school completion is completely restricted, raising the opportunity cost of dropout. The resulting fall in dropout increases school attainment, raising the proportion of students completing at least 12 years of schooling by 5 percentage points. The corresponding income gains fail to compensate for the welfare loss incurred from removing the option to re-enroll, however. The results suggest that the option to re-enroll is an important component of the incentives South African youth face when making schooling decisions.
Sharing lattices throughout the world: an ILDG status report

The international lattice data grid, a system for sharing gauge configuration files throughout the world, is operational for the most part. I give a status report, give some pointers on accessing lattice files, and highlight some of the available gauge configurations.
Universal quantum computation with weakly integral anyons

Harnessing non-abelian statistics of anyons to perform quantum computational tasks is getting closer to reality. While the existence of universal anyons by braiding alone such as the Fibonacci anyon is theoretically a possibility, accessible anyons with current technology all belong to a class that is called weakly integral--anyons whose squared quantum dimensions are integers. We analyze the computational power of the first non-abelian anyon system with only integral quantum dimensions--$$D(S_3)$$D(S3), the quantum double of $$S_3$$S3. Since all anyons in $$D(S_3)$$D(S3) have finite images of braid group representations, they cannot be universal for quantum computation by braiding alone. Based on our knowledge of the images of the braid group representations, we set up three qutrit computational models. Supplementing braidings with some measurements and ancillary states, we find a universal gate set for each model.
Modal Analysis for Rectangular Chirowaveguides with Metallic Walls Using the Finite-Difference Method

In this paper, using the finite-difference method, we analyze the propagation of guided modes in a rectangular chirowaveguide which consists of a conventional rectangular waveguide with perfectly conducting walls and filled with homogeneous isotropic chiral materials characterized by the constitutive relations D = ∈eE+iζeB, and H = B/μe+iζeE, where ∈e,μe, and ζe are the permittivity, permeability, and chirality of the medium, respectively. The dispersion or Brillouin diagram of this waveguiding structure is obtained numerically. Notable features of such rectangular chirowaveguides are addressed and compared with those of the nonchiral counterparts.
Alternative Models for Estimating the Cost of Equity Capital for Property/Casualty Insurers

This paper estimates the cost of equity capital for Property/Casualty insurers by applying three alternative asset pricing models: the Capital Asset Pricing Model (CAPM), the Arbitrage Pricing Theory (APT), and a unified CAPM/APT model (Wei (1988)∥. The in-sample forecast ability of the models is evaluated by applying the mean squared error method, the Theil U2 (1966) statistic, and the Granger and Newbold (1978) conditional efficiency evaluation. Based on forecast evaluation procedures, the APT and Wei's unified CAPM/APT models perform better than the CAPM in estimating the cost of equity capital for the PC insurers and a combined forecast may outperform the individual forecasts.
Exchange Rate Pass-Through in the Euro Area

Exchange rate pass-through in a set of euro area prices along the pricing chain is examined in this paper. First, a vector autoregression (VAR) approach is used to analyze the joint time-series behavior of the euro exchange rate and a system of area-wide prices in response to an exchange rate shock. Second, the impulseresponse functions from the VAR estimates are used to identify-in a "new openeconomy macroeconomics model"-the key behavioral parameters that best replicate the pattern of exchange rate pass-through in the euro area. A key finding is that traded goods-both extra-area exports and imports-behave as though they are predominately priced in euros. The area-wide findings are compared with those for other major industrial economies. [JEL F41, F31, E31]
Applications of a global nuclear structure model to studies of the heaviest elements

Abstract We present some new results on heavy element nuclear structure properties calculated on the basis of the finite-range droplet model and folded Yukawa single-particle potential. Specifically, we discuss calculations of nuclear ground state masses and microscopic corrections, α decay properties, β decay properties, fission potential energy surfaces, and spontaneous fission half-lives. These results, obtained with a global nuclear structure approach, are particularly reliable for describing the stability properties of the heaviest elements.
Polynomial detection of matrix subalgebras

The double Capelli polynomial of total degree 2t is Σ{(sgστ)x σ(1) y τ(1) x σ(2) y τ(2) ...x σ(t) y τ(t) σ, τ ∈ S t }. It was proved by Giambruno-Sehgal and Chang that the double Capelli polynomial of total degree 4n is a polynomial identity for M n (F). (Here, F is a field and M n (F) is the algebra of n x n matrices over F.) Using a strengthened version of this result obtained by Domokos, we show that the double Capelli polynomial of total degree 4n - 2 is a polynomial identity for any proper F-subalgebra of M n (F). Subsequently, we present a similar result for nonsplit inequivalent extensions of full matrix algebras.
List-coloring graphs on surfaces with varying list-sizes

Let $G$ be a graph embedded on a surface $S_\varepsilon$ with Euler genus $\varepsilon > 0$, and let $P\subset V(G)$ be a set of vertices mutually at distance at least 4 apart. Suppose all vertices of $G$ have $H(\varepsilon)$-lists and the vertices of $P$ are precolored, where $H(\varepsilon)=\Big\lfloor\frac{7 + \sqrt{24\varepsilon + 1}}{2}\Big\rfloor$ is the Heawood number. We show that the coloring of $P$ extends to a list-coloring of $G$ and that the distance bound of 4 is best possible. Our result provides an answer to an analogous question of Albertson about extending a precoloring of a set of mutually distant vertices in a planar graph to a 5-list-coloring of the graph and generalizes a result of Albertson and Hutchinson to list-coloring extensions on surfaces.
Quantum geometry and stability of the fractional quantum Hall effect in the Hofstadter model

We study how the stability of the fractional quantum Hall effect is influenced by the geometry of band structure in lattice Chern insulators. We consider the Hofstadter model, which converges to continuum Landau levels in the limit of small flux per plaquette. This gives us a degree of analytic control not possible in generic lattice models, and we are able to obtain analytic expressions for the relevant geometric criteria. These may be differentiated by whether they converge exponentially or polynomially to the continuum limit. We demonstrate that the latter criteria play a dominant role in predicting the physics of interacting particles in Hofstadter bands in this low flux density regime. In particular, we show that the many-body gap depends monotonically on a band-geometric criterion related to the trace of the Fubini-Study metric.
Thermal stability of ceramic coated thermal protection materials in a simulated high-speed earth entry

The dimensional stability of ceramic coated thermal protection materials developed for use on advanced entry vehicles is evaluated. Dimensional stability of these ceramic materials were studied as a function of temperature and pressure during exposure to simulated atmospheric entry in an arc-jet facility.
Computation of the high temperature Coulomb density matrix in periodic boundary conditions

Abstract The high temperature many-body density matrix is fundamental to path integral computation. The pair approximation, where the interaction part is written as a product of pair density matrices, is commonly used and is accurate to order τ 2 , where τ is the step size in the imaginary time. Here we present a method for systems with Coulomb interactions in periodic boundary conditions that consistently treats the all interactions with the same level of accuracy. It is shown that this leads to a more accurate high temperature solution of the Bloch equation. The method is applied to many-body simulation and tests for the isolated hydrogen atom and molecule are presented.
Flash Lidar Emulator for Hil Simulation

NASA's Autonomous Landing and Hazard Avoidance Technology (ALHAT) project is building a system for detecting hazards and automatically landing controlled vehicles safely anywhere on the Moon. The Flash Light Detection And Ranging (LIDAR) sensor is used to create on-the-fly a 3D map of the unknown terrain for hazard detection. As part of the ALHAT project, a hardware-in-the-loop (HIL) simulation testbed was developed to test the data processing, guidance, and navigation algorithms in real-time to prove their feasibility for flight. Replacing the Flash LIDAR camera with an emulator in the testbed provided a cheaper, safer, more feasible way to test the algorithms in a controlled environment. This emulator must have the same hardware interfaces as the LIDAR camera, have the same performance characteristics, and produce images similar in quality to the camera. This presentation describes the issues involved and the techniques used to create a real-time flash LIDAR emulator to support HIL simulation.
Validation Through Full-Scale Flight Exploration

Objectives: a) Regain Stable Platform: 1) Metrics analogous to stability margins needed for adaptive control systems; 2) Avoid adverse structural interactions. b) Maneuverability: 1) Control vehicle within new constraints; 2) Respect structural limitations; 3) Inform pilot of new performance limitations. c) Provide ability to safely land airplane: 1) Develop safest recovery trajectory.
Measuring Questions: Relevance and its Relation to Entropy

The Boolean lattice of logical statements induces the free distributive lattice of questions. Inclusion on this lattice is based on whether one question answers another. Generalizing the zeta function of the question lattice leads to a valuation called relevance or bearing, which is a measure of the degree to which one question answers another. Richard Cox conjectured that this degree can be expressed as a generalized entropy. With the assistance of yet another important result from Janos Aczel, I show that this is indeed the case, and that the resulting inquiry calculus is a natural generalization of information theory. This approach provides a new perspective on the Principle of Maximum Entropy.
Design and analysis of a WDM client server network architecture

We propose a WDM client-server network architecture based on a passive-star-coupler-based broadcast-and-select network. In this architecture, all down-stream data traffic uses WDM data channels and all up-stream requests, up-stream control messages, and down-stream control messages use an Ethernet channel (control channel). This architecture is broadcast and multicast capable. We propose a detailed point-to-point connection-setup procedure for this architecture. The system's performance is analyzed in terms of whether the control channel or the data channels are the bottleneck. We also analyze the request delay, request's channel-holding time and system throughput following the model description. We conclude that the control channel is not a bottleneck in the system. When the user request rate is high, the server-channel scheduler is the most important adjustable factor to reduce the user response time. An illustrative analysis of FCFS scheduling policy for the system is provided.
Number of nodal domains of eigenfunctions on non-positively curved surfaces with concave boundary

It is an open problem in general to prove that there exists a sequence of $$\Delta _g$$ -eigenfunctions $$\varphi _{j_k}$$ on a Riemannian manifold (M, g) for which the number $$N(\varphi _{j_k}) $$ of nodal domains tends to infinity with the eigenvalue. Our main result is that $$N(\varphi _{j_k}) \rightarrow +\infty $$ along a subsequence of eigenvalues of density 1 if (M, g) is a non-positively curved surface with concave boundary, i.e., a generalized Sinai or Lorentz billiard. Unlike the recent closely related work of Ghosh-Reznikov-Sarnak and of the authors on the nodal domain counting problem, the surfaces need not have any symmetries.
Can Fiscal Rules Help Reduce Macroeconomic Volatility in the Latin America and Caribbean Region

The debate on fiscal policy in Europe centers on how to let automatic stabilizers work while achieving fiscal consolidation. There is significant agreement on the importance of using fiscal policy as a counter-cyclical instrument, as monetary policy can no longer play this role. In contrast, most of the discussion on fiscal policy in Latin America and the Carribean region (LAC) deals just on solvency issues, largely ignoring the effects of the economic cycle. This is surprising as LAC economies are much more volatile than their European counterparts and have been generally applying pro-cyclical fiscal policies that exacerbate volatility. Some analysts and policymakers appear to think that counter-cyclical fiscal policies are a luxury that only industrial countries can indulge in or, at least, that LAC countries (with the exception of Chile) that have successfully put in place a counter-cyclical fiscal policy need to deal first with pressing adjustment and solvency issues before they attempt to reduce the highly pro-cyclical character of their fiscal policies. The author argues that this is a major mistake because the costs of pro-cyclical fiscal policies in LAC are huge in growth and welfare terms, especially for the poor, and because pro-cyclical policies and rules tend to develop a deficit bias, thus ending up being nonsustainable and noncredible. Perry illustrates both propositions. He then examines the causes of the pro-cyclicality of fiscal policies in LAC and discusses how well-designed fiscal rules may help to deal with the political economy and credibility factors behind pro-cyclicality. He also examines conflicts between flexibility and credibility in rules, showing how a good design can both facilitate the operation of automatic stabilizers while at the same time supporting solvency goals and enhancing credibility. Perry evaluates the experience with different fiscal rules and institutions in LAC to see the extent they have helped or can help to achieve the twin goals of avoiding deficit and pro-cyclical biases.
Surface-electrode architecture for ion-trap quantum information processing

We investigate a surface-mounted electrode geometry for miniature linear radio frequencyPaul ion traps. The electrodes reside in a single plane on a substrate, and the pseudopotentialminimum of the trap is located above the substrate at a distance on the orderof the electrodes' lateral extent or separation. This architecture provides the possibilityto apply standard microfabrication principles to the construction of multiplexed iontraps, which may be of particular importance in light of recent proposals for large-scalequantum computation based on individual trapped ions.
Bayesian model averaging in R

Abstract. Bayesian model averaging has increasingly witnessed applications across an array of empirical contexts. However, the dearth of available statistical software which allows one to engage in a model averaging exercise is limited. It is common for consumers of these methods to develop their own code, which has obvious appeal. However, canned statistical software can ameliorate one’s own analysis if they are not intimately familiar with the nuances of computer coding. Moreover, many researchers would prefer user ready software to mitigate the inevitable time costs that arise when hard coding an econometric estimator. To that end, this paper describes the relative merits and attractiveness of several competing packages in the statistical environment R to implement a Bayesian model averaging exercise.
Quantum and Statistical Effects in Superspace Cosmology

The general aim of these lectures is twofold: 1) To develop a viewpoint for understanding the kinematics of quantum cosmology in the minisuperspace approximation: i.e., superspace as the space of collective excitation modes of spacetime. Emphasis here is put on the spectrum of the Lifshitz operator in spacetime and that of the Wheeler-DeWitt operator in superspace. Some established theorems on the zero-mode structure and asymptotic distribution of eigenvalues of invariant operators in curved space are invoked. 2) To apply some recent results in quantum field theory in curved spacetime to problems in quantum cosmology. Specifically, the analysis of a) infrared behavior and b) dissipative behavior of quantum fields in curved spacetimes are used to elicit the views that a) minisuperspace cosmology is the infrared limit of quantum gravity, and b) dissipative behavior appears in the minisuperspace modes which can lead to memory lost of the initial conditions.
OBDD-based universal planning for synchronized agents in non-deterministic domains

Recently model checking representation and search techniques were shown to be efficiently applicable to planning, in particular to non-deterministic planning. Such planning approaches use Ordered Binary Decision Diagrams (OBDDS) to encode a planning domain as a non-deterministic finite automaton and then apply fast algorithms from model checking to search for a solution. OBDDS can effectively scale and can provide universal plans for complex planning domains. We are particularly interested in addressing the complexities arising in non-deterministic, multi-agent domains. In this article, we present UMOP, a new universal OBDD-based planning framework for non-deterministic, multi-agent domains. We introduce a new planning domain description language, NADL, to specify non-deterministic, multi-agent domains. The language contributes the explicit definition of controllable agents and uncontrollable environment agents. We describe the syntax and semantics of NADL and show how to build an efficient OBDD-based representation of an NADL description. The UMOP planning system uses NADL and different OBDD-based universal planning algorithms. It includes the previously developed strong and strong cyclic planning algorithms. In addition, we introduce our new optimistic planning algorithm that relaxes optimality guarantees and generates plausible universal plans in some domains where no strong nor strong cyclic solution exists. We present empirical results applying UMOP to domains ranging from deterministic and single-agent with no environment actions to non-deterministic and multi-agent with complex environment actions. UMOP is shown to be a rich and efficient planning system.
On convergence of infinite matrix products

A necessary and sufficient condition for the convergence of an infinite right product of matrices of the form A := [ I B 0 C ] , with (uniformly) contracting submatrices C, is proven.
Trends in Arctic sea ice drift and role of wind forcing: 1992–2009

[1] We examine the spatial trends in Arctic sea ice drift speed from satellite data and the role of wind forcing for the winter months of October through May. Between 1992 and 2009, the spatially averaged trend in drift speed within the Arctic Basin is 10.6% ± 0.9%/decade, and ranges between −4% and 16%/decade depending on the location. The mean trend is dominated by the second half of the period. In fact, for the five years after a clear break point in March 2004, the average trend increased to 46% ± 5%/decade. Over the 1992–2009 period, averaged trends of wind speed from four atmospheric reanalyses are only 1% to 2%/decade. Regionally, positive trends in wind speed (of up to 9%/decade) are seen over a large fraction of the Central Arctic, where the trends in drift speeds are highest. Spatial correlations between the basin-wide trends in wind and drift speeds are moderate (between 0.40 and 0.52). Our results suggest that changes in wind speed explain a fraction of the observed increase in drift speeds in the Central Arctic but not over the entire basin. In other regions thinning of the ice cover is a more likely cause of the increase in ice drift speed.
Between entropy and subentropy

The von Neumann entropy and the subentropy of a mixed quantum state are upper and lower bounds, respectively, on the accessible information of any ensemble consistent with the given mixed state. Here we define and investigate a set of quantities intermediate between entropy and subentropy.
Population of dynamically formed triples in dense stellar systems

In dense stellar systems, frequent dynamical interactions between binaries lead to the formation of multiple systems. In this contribution we discuss the dynamical formation of hierarchically stable triples: the formation rate, main characteristics of dynamically formed population of triples and the impact of the triples formation on the population of close binaries. In particular, we estimate how much the population of blue stragglers and compact binaries could be affected.
Color superconductivity in ultra-dense quark matter

At ultra-high density, matter is expected to form a degenerate Fermi gas of quarks in which there is a condensate of Cooper pairs of quarks near the Fermi surface. This phenomenon is called color superconductivity. In these proceedings I review the underlying physics of color superconductivity and our current understanding of the possible phases of real-world quark matter. Then I consider how lattice gauge theorists would proceed to investigate the phase structure of dense quark matter if it were possible to perform the path integral numerically, i.e. if the sign problem had been solved.
Flywheel energy storage for electromechanical actuation systems

The authors describe a flywheel energy storage system designed specifically to provide load-leveling for a thrust vector control (TVC) system using electromechanical actuators (EMAs). One of the major advantages of an EMA system over a hydraulic system is the significant reduction in total energy consumed during the launch profile. Realization of this energy reduction will, however, require localized energy storage capable of delivering the peak power required by the EMAs. A combined flywheel-motor/generator unit which interfaces directly to the 20-kHz power bus represents an ideal candidate for this load leveling. The overall objective is the definition of a flywheel energy storage system for this application. The authors discuss progress on four technical objectives: (1) definition of the specifications for the flywheel-motor/generator system, including system-level trade-off analysis; (2) design of the flywheel rotor; (3) design of the motor/generator; and (4) determination of the configuration for the power management system.
Enhanced Global Symmetries and a Strong Electroweak Sector

In this talk I review the intriguing possibility of Ref. [1] that the physical spectrum of a vector-like gauge field theory exhibits an enhanced global symmetry near a chiral phase transition. A transition from the Goldstone phase to the symmetric phase is expected as the number of fermions N1 is increased to some critical value. Various investigations have suggested that a parity-doubled spectrum develops as the critical value is approached. Using an effective Lagrangian as a guide one observes that a parity doubling is associated with the appearance of an enhanced global symmetry in the spectrum of the theory. If such a near-critical theory describes symmetry breaking in the electroweak theory, the additional symmetry suppresses the contribution of the parity doubled sector to the S parameter.
The QCD Equation of State

Results for the equation of state in 2+1 flavor QCD at zero net baryon density using the Highly Improved Staggered Quark (HISQ) action by the HotQCD collaboration are presented. The strange quark mass was tuned to its physical value and the light (up/down) quark masses fixed to ml = 0:05ms corresponding to a pion mass of 160 MeV in the continuum limit. Lattices with temporal extent Nt = 6, 8, 10 and 12 were used. Since the cutoff effects for Nt > 6 were observed to be small, reliable continuum extrapolations of the lattice data for the phenomenologically interesting temperatures range 130MeV < T < 400MeV could be performed. We discuss statistical and systematic errors and compare our results with other published works.
Analyzing stigmergic learning for self-organizing mobile ad-hoc networks (MANET's)

In recent years, mobile ad-hoc networks (MANET's) have been deployed in various scenarios, but their scalability is severely restricted by the human operators' ability to configure and manage the network in the face of rapid change of the network structure and demand patterns. In this paper, we present a self-organizing approach to MANET management based on stigmergic agents and demonstrate how to analyze its performance under different deployment assumptions. Our results emphasize the importance of attention to notions from dynamical systems theory in designing and deploying multi-agent systems.
New limits on the population of normal and millisecond pulsars in the Large and Small Magellanic Clouds

We model the potentially observable populations of normal and millisecond radio pulsars in the Large and Small Magellanic Clouds (LMC and SMC, respectively) where the known population currently stands at 19 normal radio pulsars. Taking into account the detection thresholds of previous surveys, and assuming optimal period and luminosity distributions based on studies of Galactic pulsars, we estimate that there are (1.79 ± 0.20) × 104 and (1.09 ± 0.16) × 104 normal pulsars in the LMC and SMC, respectively. When we attempt to correct for beaming effects, and the fraction of high-velocity pulsars which escape the clouds, we estimate birth rates in both the LMC and SMC to be comparable and in the range of 0.5–1 pulsars per century. Although higher than estimates for the rate of core-collapse supernovae in the clouds, these pulsar birth rates are consistent with historical supernova observations in the past 300 yr. A substantial population of active radio pulsars (of the order of a few hundred thousand) has escaped the LMC and SMC and populates the local intergalactic medium. For the millisecond pulsar (MSP) population, the lack of any detections from current surveys leads to respective upper limits (at the 95 per cent confidence level) of 15 000 for the LMC and 23 000 for the SMC. Several MSPs could be detected by a currently ongoing survey of the SMC with improved time and frequency resolution using the Parkes multibeam system. Giant-pulse emitting neutron stars could also be seen by this survey.
The Rise of a Middle Class in East and Southern Africa: Implications for Food System Transformation

We show five points regarding the middle class in developing East and Southern Africa: (1) 55 per cent of the region's middle class—37 per cent of the ‘non-vulnerable’ middle class—is rural; (2) 61–83 per cent of the middle class's food is purchased; (3) processed food occupies 70–80 per cent of the class's food expenditure, with similar shares in urban and rural areas; (4) perishable products account for 44–55 per cent of the class's expenditure. Policy attention to processing and to food products ‘beyond-grains’ thus needs to be ‘mainstreamed’; and (5) the import share of food expenditure does not rise with income in urban areas. © 2015 The Authors. Journal of International Development published by John Wiley & Sons, Ltd.
On the Strength of Size Limits in Linear Genetic Programming

Bloat is a common and well studied problem in genetic programming. Size and depth limits are often used to combat bloat, but to date there has been little detailed exploration of the effects and biases of such limits. In this paper we present empirical and theoretical analyses of the effect of size limits on variable length linear structures. Specifically, we examine the relationship between size limits and the average size of individuals in a population and define the notion of size limit strength. When a size limit is strong, the average size of a population converges to a relatively stable value. When a size limit is weak, no such convergence occurs. The average size instead appears to perform a random walk within a bounded region. We use schema theory to show this is likely a result of uneven sampling of the search space.
Regional scale estimates of baseflow and factors influencing baseflow in the Upper Colorado River Basin

Abstract Study region The study region encompasses the Upper Colorado River Basin (UCRB), which provides water for 40 million people and is a vital part of the water supply in the western U.S. Study focus Groundwater and surface water can be considered a single water resource and thus it is important to understand groundwater contributions to streamflow, or baseflow, within a region. Previously, quantification of baseflow using chemical mass balance at large numbers of sites was not possible because of data limitations. A new method using regression-derived daily specific conductance values with conductivity mass balance hydrograph separation allows for baseflow estimation at sites across large regions. This method was applied to estimate baseflow discharge at 229 sites across the UCRB. Subsequently, climate, soil, topography, and land cover characteristics were statistically evaluated using principal component analysis (PCA) to determine their influence on baseflow discharge. New hydrological insights for the region Results suggest that approximately half of the streamflow in the UCRB is baseflow derived from groundwater discharge to streams. Higher baseflow yields typically occur in upper elevation areas of the UCRB. PCA identified precipitation, snow, sand content of soils, elevation, land surface slope, percent grasslands, and percent natural barren lands as being positively correlated with baseflow yield; whereas temperature, potential evapotranspiration, silt and clay content of soils, percent agriculture, and percent shrublands were negatively correlated with baseflow yield.
Fully threaded transport engine: new method for multi-scale radiative transfer

An ew ,v ery fast method for 3D radiative transfer on fully threaded grids with arbitrarily high angular resolution is presented. The method uses completely cell-based discretization, and is ideally suited for problems with diffuse background radiation, often encountered in cosmological and star formation models. We find that for accurate statistical study of intergalactic Ly α absorption lines, one needs of the order of a few hundred angular discretization elements even for models without radiative feedback from star-forming galaxies. Ke yw ords: radiative transfer ‐ methods: numerical ‐ intergalactic medium.
Limit Theorems for Height Fluctuations in a Class of Discrete Space and Time Growth Models

We introduce a class of one-dimensional discrete space-discrete time stochastic growth models described by a height function ht(x) with corner initialization. We prove, with one exception, that the limiting distribution function of ht(x) (suitably centered and normalized) equals a Fredholm determinant previously encountered in random matrix theory. In particular, in the universal regime of large x and large t the limiting distribution is the Fredholm determinant with Airy kernel. In the exceptional case, called the critical regime, the limiting distribution seems not to have previously occurred. The proofs use the dual RSK algorithm, Gessel's theorem, the Borodin–Okounkov identity and a novel, rigorous saddle point analysis. In the fixed x, large t regime, we find a Brownian motion representation. This model is equilvalent to the Seppalainen–Johansson model. Hence some of our results are not new, but the proofs are.
Identification of Social Interactions

Abstract While interest in social determinants of individual behavior has led to a rich theoretical literature and many efforts to measure these influences, a mature “social econometrics” has yet to emerge. This chapter provides a critical overview of the identification of social interactions. We consider linear and discrete choice models as well as social networks structures. We also consider experimental and quasi-experimental methods. In addition to describing the state of the identification literature, we indicate areas where additional research is especially needed and suggest some directions that appear to be especially promising.
Closing rural-urban MDG gaps in low-income countries : a general equilibrium perspective

This paper addresses policies aimed at closing the rural-urban gap for one of the Millennium Development Goals (MDGs), the under-five mortality rate (U5MR). The paper relies on the Maquette for MDG Simulations (MAMS), a computable general equilibrium model, applied to the database of an archetypical low-income country. The scenarios, which focus on the period 2013-2030, include a "business-as-usual" base scenario and policy scenarios that analyze efforts to raise the rural population up to the urban level in terms of health services or the under-five mortality rate. The policy scenarios are implemented with alternative sources of fiscal space. The results indicate that, if current trends continue, considerable progress for MDGs should be expected by 2030. If the government raises rural health services, then the decline in the rural U5MR would accelerate. If most additional resources come from foreign grants or government efficiency gains, then the repercussions for other development indicators, including poverty reduction, would be positive. However, if most additional resources are from domestic taxes or borrowing, then progress for the rural U5MR would come at the expense of less progress for other indicators. Sensitivity analysis shows that these qualitative findings are robust to different values for two parameters related to initial rural-urban cost and service gaps. However, quantitatively, the results depend on the values of these two parameters, implying that individual country characteristics strongly influence the fiscal-space requirements for and consequences of equalizing rural-urban MDG services and outcomes.