cssi/SciSciGPT-SciSciNet huggingface dataset:
Online rectangle filling

Abstract We study an online geometric problem arising in channel-aware scheduling of wireless networks, which we call the online rectangle filling. We present an online algorithm (with one-lookahead) for this problem with a competitive ratio of 1.848, improving the previously best-known 8/3-competitive algorithm in Arora et al. (2006) [4] . We also prove a lower bound of 1.6358 on the competitive ratio of the problem, improving the previous 1.6 lower bound in [4] . In addition, we give an O ( n 2 ) -time optimal algorithm for the offline version of the problem, where n is the size of the input, which improves the O ( n 3 ) -time solution in Arora and Choi (2006) [3] , Arora et al. (2006) [5] . Our techniques are based on interesting techniques and new observations of the combinatorial structures in the problem.
The pivotal role of services in transitional economies: lessons from the West

A critical lesson to be learned from developed market economies is that strategic services are at the core of an efficiently operating market system. Paradoxically, in transitional economies striving to create a private market structure, services tend to be the least developed, least appreciated, and unbalanced sector. This condition derives from the heritage of socialist countries which is largely one of supplanting these essential services functions with a command structure in which development of independent service industries lags that of manufacturing and agriculture. Improving our understanding of the significance, composition, and evolution of service industries in the development process of market economies is an important contribution to the current economic transition process. This extensive experience serves to illustrate not only the pivotal role of services in facilitating growth and development, but also the dynamic and flexible public policy toward services. Western service development, therefore, is used as a basis for projecting current and future needs of service industries in transitional economies. There is strong evidence that without efficient service industries, other sectors of the economy stagnate, a situation which must be strenuously avoided in the fragile political environment of most transitional economies.(This abstract was borrowed from another version of this item.)
AdS field theory from conformal field theory

We provide necessary and sufficient conditions for a Conformal Field Theory to have a description in terms of a perturbative Effective Field Theory in AdS. The first two conditions are well-known: the existence of a perturbative ‘1/N ’ expansion and an approximate Fock space of states generated by a finite number of low-dimension operators. We add a third condition, that the Mellin amplitudes of the CFT correlators must be well- approximated by functions that are bounded by a polynomial at infinity in Mellin space, or in other words, that the Mellin amplitudes have an effective theory-type expansion. We explain the relationship between our conditions and unitarity, and provide an analogy with scattering amplitudes that becomes exact in the flat space limit of AdS. The analysis also yields a simple connection between conformal blocks and AdS diagrams, providing a new calculational tool very much in the spirit of the S-Matrix program. We also begin to explore the potential pathologies associated with higher spin fields in AdS by generalizing Weinberg’s soft theorems to AdS/CFT. The AdS analog of Weinberg’s argument constrains the interactions of conserved currents in CFTs, but there are potential loopholes that are unavailable to theories of massless higher spin particles in flat spacetime.
Formal asymmetric hydrobromination of styrenes via copper-catalyzed 1,3-halogen migration

An enantioselective Cu(I)-catalyzed 1,3-halogen migration reaction accomplishes a formal hydrobromination by transferring a bromine activating group from a sp2 carbon to a benzylic carbon in good er and with concomitant borylation of the Ar–Br bond. Computational modelling aids in understanding the reaction outcome and suggests future directions to improve the formal asymmetric hydrobromination. The benzyl bromide can be displaced with a variety of nucleophiles to produce a wide array of functionalized products.
POLYHYDROXYLATED 3-(N-PHENYL) CARBAMOYL-2-IMINOCHROMENE DERIVATIVES AS POTENT INHIBITORS OF TYROSINE KINASE P60C-SRC

Abstract Several polyhydroxylated 3-(N-phenyl) carbamoly-2-iminochromene derivatives were synthesized and their inhibitory effects on tyrosine kinase p60 c-src were evaluated. The structure-activity relationship reveals that the positions of the hydroxylation on both the iminochromene ring and the N-phenyl-ring of the carbamoyl group strongly affect the potency of the compounds. Protein tyrosine kinases (PTK) play an important role in the signal transduction of normal and abnormal cells. 1–3 . They include transmembrane receptors for growth factors and intracellular mediators between receptors and target proteins. They mediate cell growth, mitogenic activities and cellular differentiation. Oncogenic kinases contain point mutations, deletions or fusion with other genes. Abnormal expression results in cellular transformation and carcinogenesis. 1–3 Increasing numbers of PTK inhibitors have recently been introduced as potential anticancer reagents. 4–7 They include isoflavones (genistein), 8 tyrphostins (erbstatin), 9 lavendustin analogues, 10 staurosporine analogues (dianilinophthalmides), 11 dithiobis (indole-alkanoic acid), 12 dihydroxyisoquinolines 13 and others. 4–7 For the purpose of obtaining highly specific inhibitors, bicyclic compounds as ring-constrained inhibitors of PTK have recently been introduced. 13 They are expected to interact with the flat, cleft-like catalytic cavity of the kinase domain with high specificity. Iminochromenes belong to this type of compound. 13 Several 3-carbamoyl-2-iminochromenes with weak PTK inhibitory activity toward p56 lck have been reported. 13 We have synthesized several novel polyhydroxylated 3-(N-phenyl) carbamoyl-2-iminochromenes. We found that several of them are strongly affect the potency of the compounds. The results presented here and other recent studies 21–23 support the hypothesis of Gazit 9 that it may be possible to prepare potent, specific inhibitors for various tyrosine kinases.
Overlap formulation of Majorana-Weyl fermions

Abstract An overlap method for regularizing Majorana-Weyl fermions interacting with gauge fields is presented. A mod(2) index is introduced in relation to the anomalous violation of a discrete global chiral symmetry. Most of the paper is restricted to 2 dimensions but generalizations to 2 + 8 k dimensions should be straightforward.
COMPUTER STUDIES OF THE DYNAMIC STRENGTH OF CERAMICS

Using a new constitutive model, computer studies were performed concerning the dynamic yield strength of six ceramics, SiC, TiB2, A1N, two types of B4C, and partially stabilized zirconia. The relative importance of the Bauschinger effect and the thermomechanical variables, strain, strain rate, pressure, and temperature is demonstrated in determining the time response of ceramics to high-strain-rate deformation. The constitutive model is easy to implement in a hydrodynamic computer code and successfully reproduces a variety of data for these materials.
A Continuation Method for Converting Trajectories from Patched Conics to Full Gravity Models

A method is introduced to transition space trajectories from low fidelity patched conics models to full-ephemeris n-body dynamics. The algorithm incorporates a continuation method that progressively re-converges solution trajectories in systems with incremental changes in the dynamics. Continuation is accomplished through the variation of a control parameter, which is tied to body ephemeris locations and masses, minimum flyby altitudes, and sphere of influence sizes. The intermediate models provide a continuous and differentiable path between solutions in the simplified and n-body dynamics, and the boundary values of the control parameter replicate the patched conics and full-ephemeris models exactly. Each successive step preserves the qualitative properties of the initial guess by successively altering flyby states and body masses. A similar approach to this methodology may be taken with any simplified starting guess, such as a restricted three-body model. Trajectories computed using the patched conics conversion method presented here may include gravity assists and rendezvous with any number of target bodies, so the method is ideal for constructing interplanetary or intermoon tour missions, and is amenable to patching shorter segments together to form longer tours.
Density matrix expansion for low-momentum interactions

A first step toward a universal nuclear energy density functional based on low-momentum interactions is taken using the density matrix expansion (DME) of Negele and Vautherin. The DME is adapted for non-local momentum space potentials and generalized to include local three-body interactions. Different prescriptions for the three-body DME are compared. Exploratory results are given at the Hartree-Fock level, along with a roadmap for systematic improvements within an effective action framework for the Kohn-Sham density functional theory.
Geographical region summary service for geographical routing

In a network consists of wireless mobile nodes, routing with geographical information is more efficient and scalable than methods that only relay on node connectivities. Geographical routing requires a distributed location dissemination or location database system to provide forwarding location. In this paper, we propose a novel location dissemination system called "Geographical Region Summary Service"(GRSS). Mobile nodes in GRSS proactively disseminate aggregated forwarding locations as a summary of node IDs in a defined region. This summary propagates to other regions and updates stale summaries. Each node in the network knows the exact location of every other node, or the region it resides in. Packet forwarding decisions can be made independently at each node. We introduce the system and algorithm, also summarize some findings from our simulation results in this paper
Synthesis of Polymer-supported Chiral Lithium Amide Bases and Application in Asymmetric Deprotonation of Prochiral Cyclic Ketones

Polymer-supported chiral amines were effectively prepared from amino acid derivatives and Merrifield resin. Treatment of polymer-supported amines with n-butyllithium gave the corresponding polymer-suppported chiral lithium amide bases, which were tested in the asymmetric deprotonation reactions of prochiral ketones. The trimethylsilyl enol ethers were obtained in up to 82% ee at room temperature. The polymer-supported chiral lithium amides can be readily recycled and reused without any significant loss of reactivity or selectivity.
Tax systems in the reforming socialist economies of Europe

The Policy, Research, and Extemal Affairs Complex distuibutes PRE Working Papers todisseminate the findings of work in progress and to enoourage the exchange of ideas among Bank staff and aU others interested in development issues. These papers catry the names of the authors, reflect only their views, and should he used and cited accordingly. The findings. interpretations, and conclusions are the authors' own. They should not he attributed to the World Bank. its Board of Directors. its management, or any of its member countries P ub lic D is cl os ur e A ut ho riz ed
Dosimetry for Radiation Damage Studies

A method is presented for reporting fastneutron exposure in a meaningful and unambiguous fashion. Four steps are required: determination of the shape of the neutron spectrum, fixing its absolute magnitude, choosing a reasonable energy weighting for the neutrons, and reporting the exposure in useful units. Alternative procedures are described for performing each of these steps. The exposure unit proposed is based on the amount of energy effective for causing displacements that each neutron can transfer to the lattice. Use of this approach gives an accurate comparison of damaging exposure between widely differing neutron spectra.
Phase-trafficking reagents and phase-switching strategies for parallel synthesis.

Strategies for the parallel synthesis of small molecule arrays are reviewed with an emphasis on those approaches that integrate the sciences of organic synthesis and product purification. The use of phase-trafficking reagents (PTRs) and phase-switching strategies are highlighted, which allow the rapid, parallel synthesis of small molecule arrays with built-in purification determinants.
Determinants of participation versus consumption in the Nordic Swan eco-labeled market

Abstract This paper analyzes the determinants of demand for Nordic Swan eco-labeled paper products and whether the factors determining the discrete decision to buy a Swan-labeled product are different from those that determine the quantity purchased. Using observed consumer purchase data from Denmark, we find that prices and socio-demographic characteristics have a strong impact on the decision to purchase a Swan-labeled good. The quantity consumed of Swan-labeled goods, on the other hand, is strongly affected by the availability of Swan goods, discounts, and household size.
Mixing Processes and Stellar Evolution

We review some of the mixing processes that may influence the evolution of massive stars, such as penetrative convection, and put our emphasis on those which occur in the radiative envelope. There the main transport mechanisms are a thermally driven meridian circulation, which departs significantly from the classical Eddington-Sweet description, together with turbulent motions generated by the differential rotation. This rotation-induced mixing will surround the convective core of such stars with a region of decreasing helium content, which may prevent semi-convection from ever appearing; the extent of this region depends sensitively on the rotation rate. The results are compared with those obtained earlier by Mestel (1953). Work is in progress to verify whether stars which rotate sufficiently fast may be thoroughly mixed.
Analytic Sensitivity and Approximation of Skin Buckling Constraints in Wing-Shape Synthesis

Explicit expressions for terms of the stiffness and geometric stiffness matrices are derived for the buckling analysis of trapezoidal fiber composite wing skin panels. The formulation is based on Ritz analysis using simple polynomials, and leads to explicit expressions for the analytic sensitivities of the stiffness and geometric stiffness matrices with respect to layer thickness, fiber directions, and panel shape. Integration with wing box analysis using either the equivalent plate approach or the finite element method, makes it possible to obtain sensitivities of panel buckling constraints with respect to wing planform shape or locations of internal ribs and spars. The analytic sensitivities are used to construct approximations of panel buckling constraints for integrated wing/panel design synthesis.
Divergence study of a high-aspect-ratio, forward swept wing

An experimental wind-tunnel study to determine the divergence characteristics of a high-aspect ratio, forward-swept wing has been conducted in the NASA Langley Research Center (LaRC) Transonic Dynamics Tunnel (TDT). The rectangular wing used for this study had a panel aspect ratio of 9.16 (lambda = 0 deg.) and the sweep angle could be set at lambda = 0 deg., -15 deg., -30 deg., -45 deg., or -60 deg. A rectangular wing tip shape was tested at each of these sweep angles. In addition, a tip shape parallel to the freestream flow was tested for a wing sweep angle of lambda = -45 deg. The root of the wing was cantilever mounted to the wall of the wind tunnel. Divergence conditions were measured at M = 0.4 for each sweep angle and tip configuration tested. Subcritical response techniques were used to extrapolate to the divergence conditions during the wind-tunnel test. The primary objective of this test was to obtain data which could be used to verify for this configuration the divergence prediction capability of an aeroelastic analysis code. Subsonic lifting surface theory (kernel function) aerodynamics are utilized by this particular code. The analytical predictions of divergence were found to be significantly conservative at all forward sweep angles. At lambda = -45 deg., the analysis was 14 percent conservative. The effect of the two tip shapes on the divergence dynamic pressure was predicted accurately by the analysis. The divergence condition for the tip shape parallel to the flow occurred at a dynamic pressure 14 percent higher than the divergence condition with a rectangular tip shape.
Token-DCF: An opportunistic MAC protocol for wireless networks

IEEE 802.11 DCF is the MAC protocol currently used in wireless LANs. However, due to idle and collision times, 802.11 DCF performs poorly when it comes to channel utilization, system throughput, and channel access time. To overcome these sources of inefficiency in 802.11 DCF, in this paper, we propose a distributed and dynamically adaptive MAC protocol for wireless networks, called Token-DCF. Main focus of our approach is on reducing idle and collision times by introducing an implicit token passing algorithm. In Token-DCF, a transmitting station schedules one of its neighboring stations for the next transmission epoch using a distributed opportunistic algorithm. Furthermore, packet overhearing is employed to exchange scheduling information across the network. Our simulation results show that Token-DCF achieves more than 2X improvement in system throughput and channel access delay compared to 802.11 DCF for most network configurations.
Capability-Enhanced Microscopic Simulation With Real-Time Traffic Signal Control

An application programming interface (API) is a feature that is available in some traffic simulation programs to enhance their capabilities by allowing users to customize changes in simulation such as driver behaviors, vehicle characteristics, user-defined control strategies, and advanced Intelligent Transportation Systems (ITS) applications. This paper presents an API in AIMSUN, which is a stochastic and microscopic simulation model, to evaluate a novel real-time signal control technique based on the dynamic programming (DP) algorithm. A transportation network of diamond interchanges is first created and calibrated in the AIMSUN environment. The API, which creates a dynamic link between the DP algorithm and AIMSUN, is then developed and deployed in C++. During simulation runtime, real-time traffic measurements, including vehicle counts and speeds, are provided by detectors in the network and fed into the DP algorithm that subsequently makes a decision on a signal control plan. The signal plan is then transferred back to and implemented in the simulated network, which emulates its actual operation. Extensive simulations have shown that the new signal control technique is superior to other common offline signal optimization tools in terms of handling the demand fluctuations. This paper has demonstrated that the API function is a useful tool to assess new ITS applications that are unavailable in simulation programs.
Metric tests for curvature from weak lensing and baryon acoustic oscillations

We describe a practical measurement of the curvature of the universe which, unlike current constraints, relies purely on the properties of the Robertson-Walker metric rather than any assumed model for the dynamics and content of the universe. The observable quantity is the cross-correlation between foreground mass and gravitational shear of background galaxies, which depends on the angular diameter distances dA(zl), dA(zs), and dA(zs,zl) on the degenerate triangle formed by observer, source, and lens. In a flat universe, dA(zl,zs) = dA(zs) - dA(zl), but in curved universes an additional term ∝Ωk appears and alters the lensing observables even if dA(z) is fixed. We describe a method whereby weak-lensing data can be used to solve simultaneously for dA and the curvature. This method is completely insensitive to the equation of state of the contents of the universe, or amendments to general relativity that alter the gravitational deflection of light or the growth of structure. The curvature estimate is also independent of biases in the photometric redshift scale. This measurement is shown to be subject to a degeneracy among dA, Ωk, and the galaxy bias factors that may be broken by using the same imaging data to measure the angular scale of baryon acoustic oscillations. Simplified estimates of the accuracy attainable by this method indicate that ambitious weak-lensing + baryon-oscillation surveys would measure Ωk to an accuracy ≈0.04f(σln z/0.04)1/2, where σln z is the photometric redshift error. The Fisher-matrix formalism developed here is also useful for predicting bounds on curvature and other characteristics of parametric dark energy models. We forecast some representative error levels and compare ours to other analyses of the weak-lensing cross-correlation method. We find both curvature and parametric constraints to be surprisingly insensitive to the systematic shear calibration errors.
The geologic and hydrogeologic setting of the Waste Isolation Pilot Plant

Abstract The Waste Isolation Pilot Plant (WIPP) is a mined repository for the permanent disposal of transuranic wastes. It has been constructed by the United States Department of Energy (DOE) in semiarid, sparsely inhabited rangeland in southeastern New Mexico. The disposal area is 655 m below the land surface, in bedded salt of the Late Permian (approximately 255 million-years-old) Salado Formation. The extremely low permeability of the halite and other evaporite rocks provide the primary geologic barrier assuring long-term (10,000-year-plus) isolation of the radioactive waste from the accessible environment. Extensive geologic investigations during site characterization have provided information on the stratigraphy, structure, and natural resources of the region (including hydrocarbons, potash, and groundwater), and have investigated the potential for disruption by processes such as dissolution, salt deformation, tectonic activity, and climate change. Hydrogeologic investigations have documented the physical properties of the evaporite rocks, and have identified the Culebra Dolomite Member of the overlying Rustler Formation as the most transmissive water-bearing unit in the region. If the evaporite barriers are breached by accidental drilling intrusion, the Culebra would provide the most likely pathway for radionuclide transport away from the site. Although water in the Culebra is of poor quality and none is currently used for human consumption, groundwater flow and potential radionuclide transport in the unit have been studied in detail. Results of geologic and hydrogeologic studies of the WIPP region indicate that the geologic and hydrogeologic features of the site will provide effective long-term containment of radionuclides. Geologic and hydrogeologic information is used in the performance assessment that supported the DOE’s compliance certification application to the United States Environmental Protection Agency.
The aneuploidy paradox: costs and benefits of an incorrect karyotype

Aneuploidy has a paradoxical effect on cell proliferation. In all normal cells analyzed to date, aneuploidy has been found to decrease the rate of cell proliferation. Yet, aneuploidy is also a hallmark of cancer, a disease of enhanced proliferative capacity, and aneuploid cells are frequently recovered following the experimental evolution of microorganisms. Thus, in certain contexts, aneuploidy might also have growth-advantageous properties. New models of aneuploidy and chromosomal instability have shed light on the diverse effects that karyotypic imbalances have on cellular phenotypes, and suggest novel ways of understanding the role of aneuploidy in development and disease.
MRFy: remote homology detection for beta-structural proteins using Markov random fields and stochastic search

We introduce MRFy, a tool for protein remote homology detection that captures beta-strand dependencies in the Markov random field. Over a set of 11 SCOP beta-structural superfamilies, MRFy shows a 14 percent improvement in mean Area Under the Curve for the motif recognition problem as compared to HMMER, 25 percent improvement as compared to RAPTOR, 14 percent improvement as compared to HHPred, and a 18 percent improvement as compared to CNFPred and RaptorX. MRFy was implemented in the Haskell functional programming language, and parallelizes well on multi-core systems. MRFy is available, as source code as well as an executable, from http://mrfy.cs.tufts.edu/.
An intramolecular immonium ion variation of the Diels-Alder reaction: synthesis of (.+-.)-dihydrocannivonine

Synthese du compose du titre (methyl-1 perhydro methano-2,5 quinoleine) via une addition intramoleculaire de Diels Alder du cation iminium obtenu a partir de methylamine et de cyclohexadiene-2,4 butanal
The accuracy of medical records and police reports in determining motor vehicle crash characteristics

Objective. To determine the accuracy of police, emergency department, and ambulance records in describing motor vehicle crash (MVC) characteristics when compared with a crash investigation report (CIR). Methods. This study was a retrospective record review. Sixty-three motor vehicle crash (MVC) patients transported to a university hospital emergency department via ambulance and also reported in a crash investigation record (CIR) during the period January 1993 to December 1995 comprised the study population. The crash characteristics analyzed were occupant position (OP), restraint use (RU), air bag deployment (AD), type of impact (TI), ejection (EJ), and external cause-of-injury code (EC). The accuracies of the police report (PR), the emergency department record (EDR), and the ambulance report (AR) for each patient were compared with the CIR by computing percent agreement, with 95% confidence intervals (95% CIS) for each variable and for each data source. Results. Overall average agreement was 92.9% for PR...
Consistency of lattice definitions of U(1) flux in Abelian projected SU(2) gauge theory

Abstract We reexamine the dual Abrikosov vortex under the requirement that the lattice averages of the fields satisfy exact Maxwell equations [ME]. The electric ME accounts for the total flux and the magnetic ME determines the shape of the confining string. This leads to unique and consistent definitions of flux and electric and magnetic currents at finite lattice spacing. The resulting modification of the standard DeGrand-Toussaint construction gives a magnetic current comprised of smeared monopoles.
The long-term psychobiological consequences of infant emotions: Prescriptions for the twenty-first century.

Le caractere psychologique de chaque petit enfant emerge d'interactions positives et negatives des systemes emotionnels de son cerveau avec les evenements du monde. Les systemes emotionnels positifs semblent operer comme des forces d'attraction qui capturent les espaces cognitifs, menant a leur elargissement, culture et developpement. Les emotions negatives ont tendance a retenir les activites cognitives en des chaines plus etroites et stereotypees. L'un des buts du developpement sain consiste a generer les couches interactives harmonieuses de processus emotionnels et cognitifs, par opposition a des conflits entre les emotions et les experiences cognitives. Pour comprendre de teleprocessus de maniere scientifique nous avons besoin de conceptualiser la nature profonde du cerveau emotionnel et les difficultes psychiatriques qui peuvent emerger de desequilibres sous-jacents. Bien sůr, il faut concevoir l'enfant comme une entite coherente plutot que comme une conglomeration de parties neurologiques -mais une comprehension scientifique de la maniere dont les systemes emotionnels de son cerveau opere, basee en grande partie sur l'etude de modeles animaux, peut offrir de nouvelles manieres de conceptualiser les chemins de vie que les individus peuvent choisir et la facon dont les milieux sociaux peuvent modifier ces chemins. En reconnaissant que notre comprehension basee scientifiquement demeure bien maigre, je mettrai l'accent sur les nombreux domaines de recherche que nous devrions entretenir et travailler afin de promouvoir une comprehension plus profonde de certains problemes de neuro-developpement clefs. Les effets a long terme des experiences emotionnelles infantiles sur le developpement ulterieur chez les animaux peuvent trouver un parallele dans les processus chez les enfants humains. Le premisse fondamental est qu'avec l'emergence d'une capacite habituelle a projetter leurs emotions dans le monde, les petits enfants en viennent graduellement a voir leur milieu comme des endroits fondamentalement amicaux, des endroits indifferents, ou des endroits menacants. Une grande partie de tout ceci emerge vraisemblablement de systeme du cerveau qui controlent la tristesse et la joie, et ces processus du cerveau seront plus ou moins etudies en detail dans cet article. Les experiences avec ces emotions laissent des impressions durables sur les organismes qui se developpent. Ainsi, a travers leurs vies emotionnelles precoces, les enfants peuvent devenir des oiseaux en cage ou ils peuvent devenir des etres libres et sensibles. De nouvelles idees pour encourager ces derniers sont considerees et offertes.
Synthesis of Cyclic Sphingosine 1,3-Phosphate(cSPP) Through a Photolytic Reaction.

Abstract The synthesis of cyclic sphingosine 1,3-phosphate through photolytic methodology is described starting from d - erythro -sphingosine. A bifunctional phosphorylating reagent, 2-cyanoethyl N,N -diisopropylchlorophosphoramidite, is used to introduce the cyclic 1,3-phosphate moiety. This procedure generates cSPP in four steps and in 36% overall yield.
Collective Sensing: a Fixed-Point Approach in the Metric Space

Conventional wisdom in signal processing heavily relies on the concept of inner product defined in the Hilbert space. Despite the popularity of Hilbert-space formulation, we argue it is overly-structured to account for the complexity of signals arising from the real-world. Inspired by the works on fractal image decoding and nonlocal image processing, we propose to view an image as the fixed-point of some nonexpansive mapping in the metric space in this paper. Recently proposed BM3D-based denoising and nonlocal TV filtering can be viewed as the special cases of nonexpansive mappings while differ on the choice of clustering techniques. The physical interpretation of clustering-based nonexpansive mappings is that they convey organizational principles of the dynamical system underlying the signals of interest. There is an interesting analogy between phases of matters in statistical physics and types of structures in image processing. From this perspective, image reconstruction can be solved by a deterministic-annealing based global optimization approach which collectively exploits the a priori information about unknown image. The potential of this new paradigm, which we call "ollective sensing" is demonstrated on the lossy compression application where significant gain over current state-of-the-art (SPIHT) coding scheme has been achieved.
Affine-evasive sets modulo a prime

Optimal affine-evasive set construction.Optimal non-malleable codes against affine-tampering.Improved non-malleable codes against split-state tampering. In this work, we describe a simple and efficient construction of a large subset S of F p , where p is a prime, such that the set A ( S ) for any non-identity affine map A over F p has small intersection with S.Such sets, called affine-evasive sets, were defined and constructed in 1 as the central step in the construction of non-malleable codes against affine tampering over F p , for a prime p. This was then used to obtain efficient non-malleable codes against split-state tampering.Our result resolves one of the two main open questions in 1. It improves the rate of non-malleable codes against affine tampering over F p from log ? log ? p to a constant, and consequently the rate for non-malleable codes against split-state tampering for n-bit messages is improved from n 6 log 7 ? n to n 6 .
A Mathematical Model for the Doubly-Fed Wound Rotor Generator

This paper is a mathematical analysis of a doubly-fed wound rotor machine used as a constant frequency generator. The purpose of this analysis is to derive a consistent set of circuit equations which produce constant stator frequency and constant stator voltage. Starting with instantaneous circuit equations, the necessary rotor voltages and currents are derived. The model, thus obtained, is assumed to be valid, since the resulting relationships between mechanical power and active volt-amperes agrees with the results of others. In addition, the model allows for a new interpretation of the power flow in the doubly-fed generator.
Evaluating watershed management projects

Abstract Watershed projects play an increasingly important role in managing soil and water resources throughout the world. Research is needed to ensure that new projects draw upon lessons from their predecessors’ experiences. However, the technical and social complexities of watershed projects make evaluation difficult. Quantitative and qualitative evaluation methods, which traditionally have been used separately, both have strengths and weaknesses. Combining them can make evaluation more effective, particularly when constraints to study design exist. This paper presents mixed-method approaches for evaluating watershed projects. A recent evaluation in India provides illustrations.
Quantization of spin direction for solitary waves in a uniform magnetic field

Abstract It is known that there are nonlinear wave equations with localized solitary wave solutions. Some of these solitary waves are stable (with respect to a small perturbation of initial data) and have nonzero spin (nonzero intrinsic angular momentum in the center of momentum frame). In this paper we consider vector-valued solitary wave solutions to a nonlinear Klein–Gordon equation and investigate the behavior of these spinning solitary waves under the influence of an externally imposed uniform magnetic field. We find that the only stationary spinning solitary wave solutions have spin parallel or anti-parallel to the magnetic field direction.
On the suppression of numerical oscillations using a non-linear filter

The idea of using a non-linear filtering algorithm to eliminate numerically generated oscillations is investigated. A detailed study is conducted to follow the development of numerical oscillations and their interaction with the filter. A relaxation procedure is also proposed to enhance the effectiveness of the filter. Three model problems, a 2D steady state scalar convection-diffusion equation, a 1D unsteady gas dynamics flow with shock and a 1D linear wave equation, have been designed to test the performance of the filtering algorithm. The effectiveness of the filter is assessed for convection schemes of different dispersive and diffusive characteristics, demonstrating that it is effective in eliminating oscillations with short wavelength, but oscillations of longer wavelengths are virtually unaffected. It is concluded that a proper combination of non-linear filter and dispersive numerical scheme is a viable alternative to dissipative schemes in resolving flows with sharp gradients and discontinuities.
Wave suppression by nonlinear finite-dimensional control

Abstract Korteweg–de Vries–Burgers (KdVB) and Kuramoto–Sivashinsky (KS) equations are two nonlinear partial differential equations (PDEs) which can adequately describe motion of waves in a variety of fluid flow processes. We synthesize nonlinear low-dimensional output feedback controllers for the KdVB and KS equations that enhance convergence rate and achieve stabilization to spatially uniform steady states, respectively. The approach used for controller synthesis employs nonlinear Galerkin's method to derive low-dimensional approximations of the PDEs, which are subsequently used for controller synthesis via geometric control methods. The controllers use measurements obtained by point sensors and are implemented through point control actuators. The performance of the proposed controllers is successfully tested through simulations.
A dynamic algorithm for blind separation of convolutive sound mixtures

We study an efficient dynamic blind source separation algorithm of convolutive sound mixtures based on updating statistical information in the frequency domain, and minimizing the support of time domain demixing filters by a weighted least square method. The permutation and scaling indeterminacies of separation, and concatenations of signals in adjacent time frames are resolved with optimization of l^1xl^~ norm on cross-correlation coefficients at multiple time lags. The algorithm is a direct method without iterations, and is adaptive to the environment. Computations on recorded benchmark mixtures of speech and music signals show excellent performance. The method in general separates a foreground source from a background of sounds as often encountered in realistic situations.
Formation enthalpies by mixing GGA and GGA + U calculations

Standard approximations to the density functional theory exchange-correlation functional have been extraordinary successful, but calculating formation enthalpies of reactions involving compounds with both localized and delocalized electronic states remains challenging. In this work we examine the shortcomings of the generalized gradient approximation (GGA) and GGA+U in accurately characterizing such difficult reactions. We then outline a methodology that mixes GGA and GGA+U total energies (using known binary formation data for calibration) to more accurately predict formation enthalpies. We demonstrate that for a test set of 49 ternary oxides, our methodology can reduce the mean absolute relative error in calculated formation enthalpies from approximately 7.7–21% in GGA+U to under 2%. As another example we show that neither GGA nor GGA+U alone accurately reproduces the Fe-P-O phase diagram; however, our mixed methodology successfully predicts all known phases as stable by naturally stitching together GGA and GGA+U results. As a final example we demonstrate how our technique can be applied to the calculation of the Li-conversion voltage of LiFeF3. Our results indicate that mixing energies of several functionals represents one avenue to improve the accuracy of total energy computations without affecting the cost of calculation.
Intermolecular, markovnikov hydroamination of vinylarenes with alkylamines.

A transition metal-catalyzed intermolecular hydroamination of vinylarenes with alkylamines is reported. The combination of Pd(O2CCF3)4, DPPF, and TfOH was the most effective catalyst of those tested. Control experiments without palladium, acid, or ligand all occurred in low yield. The reaction of various vinylarenes with cyclic and acyclic alkylamines in the presence of 5 mol % of this catalyst formed the corresponding arylethylamine products in moderate to high yields. For example, reactions of morpholine, 4-phenylpiperazine, 4-Boc-piperazine, isoindoline, and tetrahydroisoquinoline with styrene all occurred in 58−75% yield. Acyclic amines such as N-benzylmethylamine and n-hexylmethylamine reacted with 2-vinylnaphthalene in 63% and 53% yields, respectively. Mechanistic investigations showed that the reaction occurred through an η3-arylethyl palladium complex. The reactions of this complex with alkylamines generated product in combination with regenerating free vinylarene, Pd(0), and ammonium salt. Thus, ...
Fluorescence microscopy: a tool for studying the physical chemistry of interfaces

Abstract The technique of fluorescence microscopy is surveyed. The basic phenomenon of fluorescence and the basic instrumentation are described. The resolution limit of the technique is considered. Extensions of the basic technique to studying dynamics, interfacial behavior, and resonance energy transfer are described. The confocal scanning technique, which improves resolution perpendicular to the image plane, is described. A new and growing application of the technique to the study of surfactant monolayers at the air-water interface is presented in some detail. In this review, we present an overview of the technique of fluorescence microscopy and its application in a variety of experiments. The principal use of fluorescence microscopy has been in the domain of biology, but it has also been employed to investigate a variety of physical and chemical phenomena. As an example of the power and utility of the method, we will describe the results of investigations on Langmuir monolayers, drawing largely from our work.
Real Parameter Margin Computation for Uncertain Structural Dynamic Systems

This paper is concerned with the problem of computing real parameter margins for stabilized, structural dynamic systems with the masses, spring constants, and damping constants as uncertain parameters. Numerical algorithms for uncertain systems with multilinear parameters are investigated. It is shown that for a certain class of structural dynamic systems with small passive damping (e.g., flexible structures in space), the computational complexity of the problem can be avoided by modeling the system as a conservative plant, without loss of any practical significance. F OR lumped mass-spring-damper dynamical systems, the masses, spring constants, and damping constants appear multilinearly in the numerator and denominator of the plant transfer function.1 The parameter margin computation for a stabilized mass-spring system using a frequency-swee ping approach (e.g., Ref. 2) based on the mapping theorem of Ref. 3 can become numerically sensitive because of possible discontinuities in some frequencies, as discussed in Ref. 1. It is analytically proved in Refs. 4 and 5 that the numerical sensitivity problem encountered in Ref. 1 is caused by actual discontinuities in frequency. A similar discontinuity issue for a frequency-sweeping approach to calculate the parameter margins is also discussed in Refs. 6 and 7. It is shown in Ref. 5 that, for a stabilized, conservative system with multilinear uncertain parameters, one needs only to check for instability in the corner directions of the parameter space hyper cube, at a finite number of critical frequencies. An alternative proof based on a geometrical interpretation of the mapping theorem was presented in Ref. 8. Consequently, conservative plants have special properties that aid in parameter margin computations; i.e., the plant transfer function is real valued for all frequencies. This allows for the identification of compensator-d ependent critical frequencies where the loop transfer function becomes real valued. If uncertain parameters appear multilinearly in the plant transfer function, real parameter margin computations can be further reduced to checking system stability at only a few critical frequencies and at only the corners of a parameter space hyper cube. For nonconservative plants, however, some of the simplifications that are possible in real parameter margin computations for conservative plants are no longer valid. In that case, a more general algorithm is needed for computing real parameter margins (or real ju), which is of much current research interest.9'10 In practice, the damping constant is often the most uncertain parameter for structural dynamic systems. In that case, we may consider 1) a worst case with no damping, i.e., a conservative plant, 2) a case with fixed, nominal values of passive
On-orbit goniometric calibration for the SPIRIT III radiometer

This paper describes the goniometric calibration of the spatial RI imaging telescope (SPIRIT) III. The SPIRIT III radiometer is the primary instrument aboard the Midcourse Space Experiment (MSX) satellite which was launched on 24 April, 1996. The sensor consists of an off-axis reimaging telescope with a six-band scanning radiometer that covers the spectrum from midwave IR to longwave IR. The radiometer has five arsenic-doped silicon focal plane detector arrays which operate at temperatures between 11 and 13 K. These arrays consists of 8 by 192 pixels, with an angular separation between adjacent pixels of approximately 90 (mu) rad. A single axis scan mirror can either remain fixed, or operate at a constant 0.46 deg/sec scan rate to give programmable fields of regard of 1 by 0.75, 1 by 1.5, and 1 by 3 degrees. The calibration, which is based on a physical model of the sensor, uses ground and on-orbit observations to determine and separate effects of scan-mirror encoder non-linearity, scan-mirror readout timing and angular velocity, detector readout timing, array coalignment, and optical distortion. This paper describes the calibration methodology and gives results using observations of stellar sources acquired during on-orbit operations.
Enantioselective construction of spirocyclic oxindolic cyclopentanes by palladium-catalyzed trimethylenemethane-[3+2]-cycloaddition.

The palladium catalyzed [3+2] trimethylenemethane (TMM) cycloaddition is an efficient method for the construction of cyclopentanes. Herein, we report a catalytic asymmetric protocol for the synthesis of spirocyclic oxindolic cyclopentanes in excellent yields and enantioselectivities, allowing for the first time the construction of up to three adjacent stereogenic centers. In this process, the chiral ligand controls the diastereo- as well as enantioselectivity.
Vibrational spectrum and conformation of cyclopropyldichloroborane

Abstract The infrared (3500-40 cm −1 ) and Raman spectra (3200-0 cm −1 ) have been recorded for cyclopropyldichloroborane in both the gaseous and solid states. Additionally, the Raman spectrum of the liquid was recorded and qualitative depolarization values obtained. Only one conformation has been found in all three physical states and, on the basis of the polarized nature of the Raman band assigned as the BCl 2 antisymmetric stretch, this conformer has been identified as being the bisected structure with C s molecular symmetry. A complete vibrational assignment is proposed based on Raman depolarization data, infrared gas phase band contours, and group frequencies. These results are compared with the corresponding data in other organoboranes.
Expedient Synthesis of Fused Azepine Derivatives Using a Sequential Rhodium(II)-Catalyzed Cyclopropanation/1-Aza-Cope Rearrangement of Dienyltriazoles

A general method for the formation of fused dihydroazepine derivatives from 1-sulfonyl-1,2,3-triazoles bearing a tethered diene is reported. The process involves an intramolecular cyclopropanation of an α-imino rhodium(II) carbenoid, leading to a transient 1-imino-2-vinylcyclopropane intermediate which rapidly undergoes a 1-aza-Cope rearrangement to generate fused dihydroazepine derivatives in moderate to excellent yields. The reaction proceeds with similar efficiency on gram scale. The use of catalyst-free conditions leads to the formation of a novel [4.4.0] bicyclic heterocycle.