cssi/SciSciGPT-SciSciNet huggingface dataset:
Predicting the market potential of plug-in electric vehicles using multiday GPS data

Abstract GPS data for a year's worth of travel by 255 Seattle households illuminate how plug-in electric vehicles can match household needs. The results suggest that a battery-electric vehicle (BEV) with 100 mi of range should meet the needs of 50% of one-vehicle households and 80% of multiple-vehicle households, when charging once a day and relying on another vehicle or mode just 4 days a year. Moreover, the average one-vehicle Seattle household uses each vehicle 23 mi per day and should be able to electrify close to 80% of its miles, while meeting all its travel needs, using a plug-in hybrid electric vehicle (PHEV) with 40-mile all-electric range. Households owning two or more vehicles can electrify 50 to 70% of their total household miles using a PHEV40, depending on how they assign the vehicle across drivers each day. Cost comparisons between the average single-vehicle household owning a Chevrolet Cruze versus a Volt PHEV suggest that, when gas prices are $3.50 per gallon and electricity rates are at 11.2 ct/kWh, the Volt will save the household $535 per year in operating costs. Similarly, the Toyota Prius PHEV will provide an annual savings of $538 per year over the Corolla.
The polarization of celestial X-rays.

Net polarization of celestial X-rays could lead to specification of source mechanism producing radiation
Government fragmentation versus fiscal decentralization and corruption

This research examines the influence of government decentralization on corruption in the United States. Previous research has focused primarily on fiscal decentralization. We address whether the structure of local governments—measured in terms of the scope of services offered and the population served—has a bearing on corruption. Results show that government decentralization does not necessarily reduce corruption—the type of decentralization matters. Specifically, more general-purpose governments contribute to corruption. In contrast, the effect of special-purpose governments is mixed. The findings uniquely reveal the tension between fiscal decentralization and fragmented local governments in terms of impacts on corruption.
Automated Noninvasive Motion Measurement of Auditory Organs in Fish Using Ultrasound

A scanning underwater, ultrasonic system has been developed to measure the in vivo vibrational amplitude response of fish hearing organs to low-frequency sound. The fish is insonified with a 20-MHz source while stimulated in a single-frequency sound field. Spectral analysis of the echoes due to the acoustic impedance mismatches at the auditory organs provides the desired amplitude information. A computer-controlled scanning system allows nearly simultaneous measurements of the response of the various organs. The system is capable of measuring displacements of 12A with a spatial resolution of 0.28 mm.
Industry Classifications and Return Comovement

A company’s industry affiliation is commonly used to construct homogeneous stock groupings for portfolio risk management, relative valuation, and peer-group comparisons. A variety of industry classification systems have been adopted, however, creating disagreements as to companies’ industry assignments. This analysis of the Global Industry Classification System (GICS) and Fama–French system indicates that common movement in returns and operating performance resulting from industry effects is stronger for stocks of large companies than for those of small companies. Also, increasingly fine levels of disaggregation improve discrimination up to six-digit GICS codes, after which the benefits tail off. Stock groupings based on industry exhibit stronger out-of-sample homogeneity than groups formed from statistical cluster analysis.
Providing access to satellite imagery through OGC catalog service interfaces in support of the Global Earth Observation System of Systems

The Global Earth Observation System of Systems (GEOSS) architecture requires supporting discovery and access to large volumes of Earth Observation data. To support this application requirement in a polar ecosystem scenario, the project constructed a metadata catalog service for pre-collected orthorectified Landsat satellite images with global coverage. This study investigates the characteristics and challenges in building Open Geospatial Consortium Inc. (OGC) catalog service. It further presents a general lightweight XML adapter for relational tables, followed by a general OGC catalog service solution based on this adapter. This adapter relies on two configuration files to make the core software modules independent of the underlying metadata database structure. One configuration file identifies how XML schema is mapped into relational schema, and the other represents the XML output template. At runtime, this adapter internally employs a two-step mechanism: XQuery processing and XML publication. In the XQuery processing step, metadata discovery requests are interpreted, resulting in an SQL query clause. In the XML publication step, this SQL query and other dynamically generated queries are executed to generate the output according to the predefined XML template. Successful application of this OGC catalog service solution in the GEOSS AIP-2 polar ecosystem scenario is presented, followed by an analysis on its advantages and limitations.
Elliptic Equations in Divergence Form with Partially BMO Coefficients

The solvability in Sobolev spaces is proved for divergence form second order elliptic equations in the whole space, a half space, and a bounded Lipschitz domain. For equations in the whole space or a half space, the leading coefficients aij are assumed to be only measurable in one direction and have locally small BMO semi-norms in the other directions. For equations in a bounded domain, additionally we assume that aij have small BMO semi-norms in a neighborhood of the boundary of the domain. We give a unified approach of both the Dirichlet boundary problem and the conormal derivative problem. We also investigate elliptic equations in Sobolev spaces with mixed norms under the same assumptions on the coefficients.
On transitive algebras containing a standard finite von Neumann subalgebra

Abstract Let M be a finite von Neumann algebra acting on a Hilbert space H and A be a transitive algebra containing M ′ . In this paper we prove that if A is 2-fold transitive, then A is strongly dense in B ( H ) . This implies that if a transitive algebra containing a standard finite von Neumann algebra (in the sense of [U. Haagerup, The standard form of von Neumann algebras, Math. Scand. 37 (1975) 271–283]) is 2-fold transitive, then A is strongly dense in B ( H ) . Non-selfadjoint algebras related to free products of finite von Neumann algebras, e.g., L F n and ( M 2 ( C ) , 1 2 Tr ) ∗ ( M 2 ( C ) , 1 2 Tr ) , are studied. Brown measures of certain operators in ( M 2 ( C ) , 1 2 Tr ) ∗ ( M 2 ( C ) , 1 2 Tr ) are explicitly computed.
Geometric nullstellensatz and symbolic powers on arbitrary varieties

In recent years, a multiplier ideal defined on arbitrary varieties, so called Mather–Jacobian multiplier ideal, has been developed independently by Ein–Ishii–Mustata and de Fernex–Docampo. With this new tool, we have a chance of extending some classical results proved in nonsingular case to arbitrary varieties to establish their general forms. In this paper, we first extend a result of geometric nullstellensatz due to Ein–Lazarsfeld in nonsingular case to any projective varieties. Then we prove a result on comparison of symbolic powers with ordinary powers on any varieties, which extends results of Ein–Lazarsfeld–Smith and Hochster–Huneke.
How to Compress Interactive Communication

We describe new ways to simulate two-party communication protocols to get protocols with potentially less communication. We show that every communication protocol that communicates $C$ bits and reveals $I$ bits of information about the inputs to the participating parties can be simulated by a new protocol involving at most $\tilde{O}(\sqrt{CI})$ bits of communication. If the protocol reveals $I$ bits of information about the inputs to an observer that watches the communication in the protocol, we show how to carry out the simulation with $\tilde{O}(I)$ bits of communication. These results lead to a direct sum theorem for randomized communication complexity. Ignoring polylogarithmic factors, we show that for worst-case computation, computing $n$ copies of a function requires $\sqrt{n}$ times the communication required for computing one copy of the function. For average case complexity, given any distribution $\mu$ on inputs, computing $n$ copies of the function on $n$ inputs sampled independently according...
A blob method for the aggregation equation

Author(s): Craig, Katy; Bertozzi, Andrea L | Abstract: Motivated by classical vortex blob methods for the Euler equations, we develop a numerical blob method for the aggregation equation. This provides a counterpoint to existing literature on particle methods. By regularizing the velocity field with a mollifier or "blob function", the blob method has a faster rate of convergence and allows a wider range of admissible kernels. In fact, we prove arbitrarily high polynomial rates of convergence to classical solutions, depending on the choice of mollifier. The blob method conserves mass and the corresponding particle system is both energy decreasing for a regularized free energy functional and preserves the Wasserstein gradient flow structure. We consider numerical examples that validate our predicted rate of convergence and illustrate qualitative properties of the method.
CONFORMATIONAL PREFERENCES OF SPIROCYCLIC PENTAOXYPHOSPHORANES VARYING IN RING SIZE

Abstract New bicyclic pentaoxyphosphoranes 1–3 containing ring sizes varying from five to seven membered were synthesized by oxidative addition of a quinone or a diol to a cyclic phosphite. Variable-temperature solution 1H and 13C NMR studies revealed the presence of dynamic intramolecular ligand exchange processes, one in which apical-equatorial ring interchange occurred between trigonal bipyramidal ground states and a higher temperature process supporting an exchange intermediate with the ring located diequatorially in a trigonal bipyramid. Activation energies for the latter process were determined. X-ray analysis supported the interpretation of the solution-state behavior and showed that saturated six-membered rings prefer a boat conformation occupying apical-equatorial positions in trigonal bipyramidal structures. The stability of the six-membered ring in this conformation is supported by the shorter P-O bond lengths found for this ring size compared to that for phosphoranes having five- and seven-mem...
A Gamma Ray Monitor for the OSO-7 Spacecraft

A 3" × 3" NaI(Tl) gamma ray (0.3 to 10 MeV) spectrometer with a CsI(Na) charged particle and anti-Compton shield has been developed for the ORBITING SOLAR OBSERVATORY (OSO-7) which was launched September 30, 1971. The instrument, designed for a rotating wheel compartment, utilizes a 377 channel quadratic PHA with accumulation times of 3, 1, or 0.5 minutes. Quick look and calibration data obtained via a direct data link to a minicomputer at the UNH campus allows near real time monitoring and control of the experiment. Various commands changing the operating mode can be executed. The functions which can be commanded include: rotation of the quadrants in which data is collected by 90°; gain adjustment of the central detector over a 6:1 range; manual or automatic sequencing of calibrations; variation of accumulation times by telemetering selected channels; and selection of reference directions. A small X-ray detector covering the range 7.5 to 120 keV is also included.
On the classification of warped product Einstein metrics

The question of when an Einstein metric can be written as a warped product is posed in the text Einstein metrics by Besse. Recently, there have been some interesting results about these spaces found by KimKim, CaseShuWei, and Case. They take the perspective of studying these metrics by studying the equation on the base of the warped product. The resulting equation is similar to the Ricci soliton equation and is a natural equation from the work of Bakry Emery and their collaborators on curvature dimension inequalities. We will also take this perspective and prove two new results: one is an extension of the work of Kim and Kim and Case-Shu-Wei to manifolds with boundary; the other is a classi cation result of warped products Einstein metrics over locally conformally at base space.
Structure and cation distribution of new ternary vanadates FeMg2V3O11 and FeZn2V3O11

Abstract FeMg 2 V 3 O 11 crystals grown from a MgO/Fe 2 O 3 /V 2 O 5 melt crystallize in the triclinic space group P-1 with parameters: a =6.434(1) A, b =6.806(1) A, c =10.085(1) A, α =97.44(1)°, β =103.44(1)°, γ =101.56(1)° and Z =2. FeZn 2 V 3 O 11 crystals grown from a ZnO/Fe 2 O 3 /V 2 O 5 melt also crystallize in P-1 with similar parameters: a =6.455(1) A, b =6.834(1) A, c =9.988(1) A, α =97.65(1)°, β =102.61(1)°, γ =101.26(1)° and Z =2. Both are isostructural with GaZn 2 V 3 O 11 , and susceptibility measurements reveal that all iron is high spin d 5 . In FeMg 2 V 3 O 11 , Fe 3+ is distributed non-statistically with Mg 2+ on octahedral and bipyramidal sites. In FeZn 2 V 3 O 11 , Fe 3+ is found only on the octahedral sites and Zn 2+ exclusively occupies the bipyramidal sites.
How to Find More Supernovae with Less Work: Object Classification Techniques for Difference Imaging

We present the results of applying new object classificationtechniques to difference images in the context of the Nearby SupernovaFactory supernova search. Most current supernova searches subtractreference images from new images, identify objects in these differenceimages, and apply simple threshold cuts on parameters such as statisticalsignificance, shape, and motionto reject objects such as cosmic rays,asteroids, and subtraction artifacts. Although most static objectssubtract cleanly, even a very low false positive detection rate can leadto hundreds of non-supernova candidates which must be vetted by humaninspection before triggering additional followup. In comparison to simplethreshold cuts, more sophisticated methods such as Boosted DecisionTrees, Random Forests, and Support Vector Machines provide dramaticallybetter object discrimination. At the Nearby Supernova Factory, we reducedthe number of non-supernova candidates by a factor of 10 while increasingour supernova identification efficiency. Methods such as these will becrucial for maintaining a reasonable false positive rate in the automatedtransient alert pipelines of upcoming projects such as PanSTARRS andLSST.
Admissible transverse surgery does not preserve tightness

We produce the first examples of closed, tight contact 3-manifolds which become overtwisted after performing admissible transverse surgeries. Along the way, we clarify the relationship between admissible transverse surgery and Legendrian surgery. We use this clarification to study a new invariant of transverse knots—namely, the range of slopes on which admissible transverse surgery preserves tightness—and to provide some new examples of knot types which are not uniformly thick. Our examples also illuminate several interesting new phenomena, including the existence of hyperbolic, universally tight contact 3-manifolds whose Heegaard Floer contact invariants vanish (and which are not weakly fillable); and the existence of open books with arbitrarily high fractional Dehn twist coefficients whose compatible contact structures are not deformations of co-orientable taut foliations.
On the scaling limit of a singular integral operator

The scaling limit and Schauder bounds are derived for a singular integral operator arising from a difference equation approach to monodromy problems.
Selective object encryption for privacy protection

This paper introduces a new recursive sequence called the truncated P-Fibonacci sequence, its corresponding binary code called the truncated Fibonacci p-code and a new bit-plane decomposition method using the truncated Fibonacci pcode. In addition, a new lossless image encryption algorithm is presented that can encrypt a selected object using this new decomposition method for privacy protection. The user has the flexibility (1) to define the object to be protected as an object in an image or in a specific part of the image, a selected region of an image, or an entire image, (2) to utilize any new or existing method for edge detection or segmentation to extract the selected object from an image or a specific part/region of the image, (3) to select any new or existing method for the shuffling process. The algorithm can be used in many different areas such as wireless networking, mobile phone services and applications in homeland security and medical imaging. Simulation results and analysis verify that the algorithm shows good performance in object/image encryption and can withstand plaintext attacks.
The HERMES dual-radiator RICH detector

Abstract The HERMES experiment emphasizes measurements of semi-inclusive deep-inelastic scattering. Most of the hadrons produced lie between 2 and 10 GeV , a region in which it had not previously been feasible to separate pions, kaons, and protons with standard particle identification (PID) techniques. The recent development of new clear, large, homogeneous and hydrophobic silica aerogel material with a low index of refraction offered the means to apply RICH PID techniques to this difficult momentum region. The HERMES instrument uses two radiators, C 4 F 10 , a heavy fluorocarbon gas, and a wall of silica aerogel tiles. A lightweight spherical mirror constructed using a newly perfected technique to make resin-coated carbon-fiber surfaces of optical quality provides optical focusing on a photon detector consisting of 1934 photomultiplier tubes (PMT) for each detector half. The PMT array is held in a soft steel matrix to provide shielding against the residual field of the main spectrometer magnet. Ring reconstruction is accomplished with pattern recognition techniques based on a combination of inverse and direct ray tracing.
Universal Four-Component Fermi Gas in One Dimension

A four-component Fermi gas in one dimension with a short-range four-body interaction is shown to exhibit a one-dimensional analog of the BCS-BEC crossover. Its low-energy physics is governed by a Tomonaga-Luttinger liquid with three spin gaps. The spin gaps are exponentially small in the weak coupling (BCS) limit where they arise from the charge-density-wave instability, and become large in the strong coupling (BEC) limit because of the formation of tightly bound tetramers. We investigate the ground-state energy, the sound velocity, and the gap spectrum in the BCS-BEC crossover and discuss exact relationships valid in our system. We also show that a one-dimensional analog of the Efimov effect occurs for five bosons while it is absent for fermions. Our work opens up a very rich field of universal few-body and many-body physics in one dimension.
The Bergman reaction as a synthetic tool: advantages and restrictions

Abstract The Bergman cycloaromatization reaction efficiently converts easily prepared acyclic enediynes into aromatic rings. In order to prepare larger, functionalized fused aromatic systems using this reaction, a thorough understanding of how functionalization affects cycloaromatization is necessary. We present here our studies on the influence of substituents at three different functionalization sites on cycloaromatization, and how these functional groups can be tailored to prepare more complex systems.
High-lifetime strained Si1-xGex films grown by rapid thermal chemical vapor deposition

Abstract The electrical and optical properties of strained epitaxial Si 1-x Ge x films on silicon have been examined to determine the potential application of the material for integrated infrared sensors on silicon substrates. The generation lifetime in films grown by rapid thermal chemical vapor deposition was found to be in excess of 1 μs, which is important for the fabrication of sensors with high shunt impedances. By comparison of the well-resolved photoluminescence of these films with absorption data, it is also concluded that the initial absorption mechanism in these alloys proceeds by a no-phonon process, despite the fact that the films have an indirect bandgap.
Efficient data dissemination using locale covers

Location-dependent data are central to many emerging applications, ranging from traffic information services to sensor networks. The standard pull- and push-based data dissemination models become unworkable since the data volumes and number of clients are high. We address this problem using locale covers, a subset of the original set of locations of interest, chosen to include at least one location in a suitably defined neighborhood of any client. Since location-dependent values are highly correlated with location, a query can be answered using a location close to the query point. Typical closeness measures might be Euclidean distance, or a k-nearest neighbor criterion. We show that location-dependent queries may be answered satisfactorily using locale covers. Our approach is independent of locations and speeds of clients, and is applicable to mobile clients. We also introduce a nested locale cover scheme that ensures fair access latencies, and allows clients to refine the accuracy of their information over time. We also prove two important results: one regarding the greedy algorithm for sensor covers and the other pertaining to randomized locale covers for k-nearest neighbor queries.
Thiazolidinethiones vs. imidazolidinedithiones as products from cyanothioformanilides and phenyl isothiocyanates

The formation of thiazolidinethiones 3 and/or imidazolidinedithiones 5 from cyanothioformanilides and aryl isothiocyanates is found to be dependent upon the type of bases used, reaction temperature and the nature and position of substituents on cyanothioformanilides. Examples are presented.
Dislocation Multiplication in the Early Stage of Deformation in Mo Single Crystals

Initial dislocation structure in annealed high-purity Mo single crystals and deformation substructure in a crystal subjected to 1% compression have been examined and studied using transmission electron microscopy (TEM) techniques in order to investigate dislocation multiplication mechanisms in the early stage of plastic deformation. The initial dislocation density is in a range of 10{sup 6} {approx} 10{sup 7} cm{sup -2}, and the dislocation structure is found to contain many grown-in superjogs along dislocation lines. The dislocation density increases to a range of 10{sup 8} {approx} 10{sup 9} cm{sup -2}, and the average jog height is also found to increase after compressing for a total strain of 1%. It is proposed that the preexisting jogged screw dislocations can act as (multiple) dislocation multiplication sources when deformed under quasi-static conditions. The jog height can increase by stress-induced jog coalescence, which takes place via the lateral migration (drift) of superjogs driven by unbalanced line-tension partials acting on link segments of unequal lengths. The coalescence of superjogs results in an increase of both link length and jog height. Applied shear stress begins to push each link segment to precede dislocation multiplication when link length and jog height are greater than critical lengths. This ''dynamic'' dislocation multiplication source is suggested to be crucial for the dislocation multiplication in the early stage of plastic deformation in Mo.
Branes, black holes and topological strings on toric Calabi-Yau manifolds

We develop means of computing exact degeneracies of BPS black holes on toric Calabi-Yau manifolds. We show that the gauge theory on the D4 branes wrapping ample divisors reduces to 2D q-deformed Yang-Mills theory on necklaces of P1's. As explicit examples we consider local P2, P1 × P1 and Ak type ALE space times C. At large N the D-brane partition function factorizes as a sum over squares of chiral blocks, the leading one of which is the topological closed string amplitude on the Calabi-Yau. This is in complete agreement with the recent conjecture of Ooguri, Strominger and Vafa.
Self-supervised dynamical systems

Abstract A new type of dynamical systems which capture the interactions via information flows typical for active multi-agent systems is introduced. The mathematical formalism is based upon coupling the classical dynamical system (with random components caused by uncertainties in initial conditions as well as by Langevin forces) with the corresponding Liouville or the Fokker–Planck equations describing evolution of these uncertainties in terms of probability density. The coupling is implemented by information-based supervising forces which fundamentally change the patterns of probability evolution. It is demonstrated that the probability density can approach prescribed attractors while exhibiting such patterns as shock waves, solitons and chaos in probability space. Applications of these phenomena to information-based neural nets, expectation-based cooperation, self-programmed systems, control chaos using terminal attractors as well as to games with incomplete information, are addressed. A formal similarity between the mathematical structure of the introduced dynamical systems and quantum mechanics is discussed.
Resolution of causal paradoxes arising from opposing thermodynamic arrows of time

Abstract It was recently shown (L.S. Schulman, Phys. Rev. Lett. 83 (1999) 5419) that systems with opposite thermodynamic arrows of time could have moderate mutual interaction with neither destroying the order of the other. Such interaction includes signaling. Signals, however, may give rise to causal paradoxes, suggesting that “moderate” interaction may be impossible. Using the two-time boundary condition framework, we resolve the paradoxes. In one example, at a macroscopic level, we establish the existence of solutions to the appropriate boundary value problem. This result is extended to a class of microscopic problems. We also produce an example in which microscopic data are given and there is no solution. This is a different kind of resolution: there is no paradox because the events do not happen. Finally we discuss the differences between these cases.
Selective One-Pot Synthesis of Allenyl and Alkynyl Esters from β-Ketoesters

A convenient method is described for the dehydration of β-ketoesters to generate conjugated and deconjugated alkynyl esters and conjugated allenyl esters. This sequential one-pot method involves the formation of a vinyl triflate monoanion intermediate that leads to the selective formation of alkynes or allenes depending on additives and conditions used. Product outcomes appear to be a function of unique mono- and dianion mechanisms which are described.
Pulsars as Spiral Arm Tracers

Pulsars are used to trace the spiral arms of the Galaxy. Present pulsar characteristics are used to divide them into two pulsar types as defined by Huang (1987). The ages of Type II pulsars and the galactic rotation curve are used to determine their position at birth. The spiral arm pattern velocity is used to reconstruct the arms from which the individual Type II pulsars originated. It is found that the best fit to the data requires spiral arm segments with a pitch angle of 14.5 deg.
Bi-parameter paraproducts

In the first part of the paper we prove a bi-parameter version of a well known multilinear theorem of Coifman and Meyer. As a consequence, we generalize the Kato-Ponce inequality in nonlinear PDE, obtaining a fractional Leibnitz rule for derivatives in the $x_1$ and $x_2$ directions simultaneously. Then, we show that the double bilinear Hilbert transform does not satisfy any $L^p$ estimates.
The oxidative spirocyclization of 2-(ω-(OH)-alkyl)cyclic enol ethers by rhenium (VII)-oxide

Abstract 2-(ω-(OH)-Alkyl)cyclic enol ethers react with rhenium(VII)-oxide to directly provide spiroketal alcohols resulting from an intramolecular syn oxidation of the enol ether double bond.
Copper(I)-catalyzed diastereoselective hydroxytrifluoromethylation of dienes accelerated by phosphine ligands

A diastereoselective 1,4-hydroxytrifluoromethylation of dienes is catalyzed by copper cyanide–phosphine complexes. This reaction is significantly accelerated by bulky monodentate phosphines, and the discovery enables expedient access to a variety of CF3-containing allylic alcohol derivatives.
HOMOTOPY GROUPS OF MODULI SPACES OF STABLE QUIVER REPRESENTATIONS

The purpose of this paper is to describe a method for computing homotopy groups of the space of α-stable representations of a quiver with fixed dimension vector and stability parameter α. The main result is that the homotopy groups of this space are trivial up to a certain dimension, which depends on the quiver, the choice of dimension vector, and the choice of parameter. As a corollary we also compute low dimensional homotopy groups of the moduli space of α-stable representations of the quiver with fixed dimension vector, and apply the theory to the space of non-degenerate polygons in three-dimensional Euclidean space.
Quantum graphs: II. Some spectral properties of quantum and combinatorial graphs

The paper deals with some spectral properties of (mostly infinite) quantum and combinatorial graphs. Quantum graphs have been intensively studied lately due to their numerous applications to mesoscopic physics, nanotechnology, optics and other areas. A Schnol-type theorem is proven that allows one to detect that a point λ belongs to the spectrum when a generalized eigenfunction with an sub-exponential growth integral estimate is available. A theorem on spectral gap opening for 'decorated' quantum graphs is established (its analogue is known for the combinatorial case). It is also shown that if a periodic combinatorial or quantum graph has a point spectrum, it is generated by compactly supported eigenfunctions ('scars').
Infrared spectroscopic characterization of the low-albedo materials on Iapetus

Abstract Iapetus, one of the large satellites of Saturn, has been studied over the centuries for its signature brightness contrast, light on one side and dark on the opposite. It has recently been suggested that the dark material is a combination of native and exogenous materials with distinct histories. We present an analysis of parts of the Cassini Regio, the darkest region on the leading hemisphere of Iapetus, focusing on the hydrocarbon signature with a view to detect and investigate differences in the material(s). We find variations in the hydrocarbon bands with geographic location, one type predominantly located on the leading hemisphere. A comparison with the equivalent spectral features on Phoebe and Hyperion reveals a predictable resemblance between the leading hemisphere material and Phoebe and an unexpected likeness between Hyperion’s darkest material and Iapetus’ trailing hemisphere surface. An analysis of the slope in the visible part of the spectrum is strongly affected by a rise in the continuum (∼0.35–0.65 μm) attributed to Rayleigh scattering from nano-size particles on the surface. The continuum rise varies in strength with the albedo and H 2 O ice content, and when it is properly accounted for, the overall slope in all the identified spectral units is the same over the interval 0.35–2.3 μm, independent of albedo or ice abundance. The interpretation of current and previous results offers two different scenarios illustrated by the presence of one vs. two dark materials distributed over the Iapetus surface. We describe the scenarios and their implications. The appearance of the aromatic and aliphatic absorption bands together in their measured relative strengths makes this spectral signature unique, and thus enables the comparison among the three satellites.
Rejection of RFI by means of interferometry

The feasibility of using radio interferometry to reduce the levels of RF interference (RFI) encountered in the NASA Targeted Search SETI program is discussed. It is shown that a radio interferometer will be much less sensitive to RFI than a single antenna system. However, the use of an interferometer would entail a reduction in the noise-limited sensitivity of the system as well as some additional costs due to added complexity.
Spherical foams in flat space

Regular tessellations of three dimensional space are characterized through their Schlafli symbols {p, q, r}, where each cell has regular p-gonal sides, q sides meeting at each vertex of a cell, and r cells meeting around each edge. Regular tessellations with symbols {p, 3, 3} all satisfy Plateau's laws for equilibrium foams. For general p, however, these regular tessellations do not embed in Euclidean space, but require a uniform background curvature. We study a class of regular foams on S3 which, through conformal, stereographic projection to 3 define irregular cells consistent with Plateau's laws. We analytically characterize a broad classes of bulk foam bubbles, and extend and explain recent observations on foam structure and shape distribution.
Multi-Utilitarianism in Two-Agent Quasilinear Social Choice

We introduce a new class of rules for resolving quasilinear social choice problems. These rules extend those of Green. We call such rules multi-utilitarian rules. Each multi-utilitarian rule is associated with a probability measure over the set of weighted utilitarian rules, and is derived as the expectation of this probability. These rules are characterized by the axioms efficiency, translation invariance, monotonicity, continuity, and additivity. By adding recursive invariance, we obtain a class of asymmetric rules generalizing those Green characterizes. A multi-utilitarian rule satisfying strong monotonicity has an associated probability measure with full support.
Counting trees using symmetries

We prove a new formula for the generating function of multitype Cayley trees counted according to their degree distribution. Using this formula we recover and extend several enumerative results about trees. In particular, we extend some results by Knuth and by Bousquet-Melou and Chapuy about embedded trees. We also give a new proof of the multivariate Lagrange inversion formula. Our strategy for counting trees is to exploit symmetries of refined enumeration formulas: proving these symmetries is easy, and once the symmetries are proved the formulas follow effortlessly. We also adapt this strategy to recover an enumeration formula of Goulden and Jackson for cacti counted according to their degree distribution.
Heterotic and type I string dynamics from eleven-dimensions

Abstract We propose that the ten-dimensional E 8 × E 8 heterotic string is related to an eleven-dimensional theory on the orbifold R 10 × S 1 / Z 2 in the same way that the Type IIA string in ten dimensions is related to R 10 × S 1 . This in particular determines the strong coupling behavior of the ten-dimensional E 8 × E 8 theory. It also leads to a plausible scenario whereby duality between SO (32) heterotic and Type I superstrings follows from the classical symmetries of the eleven-dimensional world, just as the SL(2, Z ) duality of the ten-dimensional Type IIB theory follows from eleven-dimensional diffeomorphism invariance.
Mechanism of Film Growth of Tellurium by Electrochemical Deposition in the Presence and Absence of Cadmium Ions

The growth morphology and the kinetics of a thin film of Te on Au during electrochemical deposition at −62 mV (vs Ag/AgCl/3 M NaCl) have been studied. The deposition conditions are similar to those used previously by us to grow nanowires inside Au nanotubes by electrochemical deposition in the presence of Cd ions (Cd2+). By using electrochemical deposition on a planar Au electrode, we explored the growth of the Te film for two conditions: in the presence of Cd2+ (0.1 mM TeO2 + 1 mM CdSO4 + 50 mM H2SO4 solution) and in the absence of Cd2+ (0.1 mM TeO2 + 50 mM H2SO4 solution). We used several surface investigation techniques to study the growth such as: in situ electrochemical atomic force microscopy (EC-AFM), in situ electrochemical surface plasmon resonance (EC-SPR), electrochemical methods, scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). In the presence of Cd2+, in situ electrochemical atomic microscopy showed that Cd2+ acted as a mediator at the early deposition stage an...
GPU-Based Parallelization for Fast Circuit Optimization

The progress of GPU (Graphics Processing Unit) technology opens a new avenue for boosting computing power. This work is an attempt to exploit the GPU for accelerating VLSI circuit optimization. We propose GPU-based parallel computing techniques and apply them on simultaneous gate sizing and threshold voltage assignment, which is a popular method for VLSI performance and power optimization. These techniques include efficient task scheduling and memory organization, all of which are aimed to fully utilize the advantages of GPUs. Compared to conventional sequential computation, our techniques can provide up to 56× (39× on average) speedup without any sacrifice on solution quality.
Joint pricing and inventory control with a Markovian demand model

Abstract We consider the joint pricing and inventory control problem for a single product over a finite horizon and with periodic review. The demand distribution in each period is determined by an exogenous Markov chain. Pricing and ordering decisions are made at the beginning of each period and all shortages are backlogged. The surplus costs as well as fixed and variable costs are state dependent. We show the existence of an optimal (s, S, p)-type feedback policy for the additive demand model. We extend the model to the case of emergency orders. We compute the optimal policy for a class of Markovian demand and illustrate the benefits of dynamic pricing over fixed pricing through numerical examples. The results indicate that it is more beneficial to implement dynamic pricing in a Markovian demand environment with a high fixed ordering cost or with high demand variability.
Laboratory measurements of the W band (3.2 mm) properties of phosphine (PH3) and ammonia (NH3) under simulated conditions for the outer planets

[1] A model, based on the Van Vleck-Weisskopf line shape, was developed for the centimeter-wavelength opacity of PH3, which provides an order of magnitude improvement over previous models [Hoffman et al., 2001]. New laboratory measurements indicate that the model is also accurate at 94 GHz (3.2 mm) under conditions for the outer planets. Measurements of the opacity and refractivity of PH3 in a hydrogen/helium (H2/He) atmosphere were conducted at 94 GHz (3.2 mm) at pressures of 0.5 and 2 bars and at temperatures of 293 K and 213 K. Additionally, new high-precision laboratory measurements of the opacity and refractivity of NH3 in an H2/He atmosphere were conducted at the same frequency at pressures from 0.5 to 2 bars and at temperatures of 204 K, 211 K, and 290 K. Results show that existing models, which predict NH3 opacity in an H2/He environment, understate the absorption due to the pressure broadened rotational lines. A new model is proposed for use at 94 GHz (3.2 mm) which uses a Ben-Reuven line shape [Ben-Reuven, 1966] for the inversion lines and a Kinetic line shape [Gross, 1955] for the rotational lines. Results of measurements of both PH3 and NH3 can be used to better interpret maps of Saturn's emission at this wavelength and can potentially be used to deduce spatial variations in the abundances of both gases in the atmosphere of Saturn.
Evidence for a chemoautotrophically based food web at inactive hydrothermal vents (Manus Basin)

Hydrothermal vents are ephemeral systems. When venting shuts down, sulfide-dependent taxa die off, and non-vent taxa can colonize the hard substrata. In Manus Basin (Papua New Guinea), where hydrothermally active and inactive sites are interspersed, hydroids, cladorhizid sponges, barnacles, bamboo corals, and other invertebrate types may occupy inactive sites. Carbon and nitrogen isotopic compositions of animals occupying inactive sites are consistent with nutritional dependence on either chemoautotrophically or photosynthetically produced organic material, but sulfur isotopic compositions of these animals point to a chemoautotrophic source of sulfur from dissolved sulfide in vent fluids rather than sulfur derived from seawater sulfate through photosynthesis. Given that suspension-feeding and micro-carnivorous invertebrates are the biomass dominants at inactive sites, the primary source of chemoautotrophic nutrition is likely suspended particulates and organisms delivered from nearby active vents.
Strong q-convexity in uniform neighborhoods of subvarieties in coverings of complex spaces

The main result is that, for any projective compact analytic subset Y of dimension q > 0 in a reduced complex space X, there is a neighborhood Ω of Y such that, for any covering space \({\Upsilon\colon\widehat X\to X}\) in which \({\widehat Y\equiv\Upsilon^{-1}(Y)}\) has no noncompact connected analytic subsets of pure dimension q with only compact irreducible components, there exists a C∞ exhaustion function \({\varphi}\) on \({\widehat X}\) which is strongly q-convex on \({\widehat\Omega=\Upsilon^{-1}(\Omega)}\) outside a uniform neighborhood of the q-dimensional compact irreducible components of \({\widehat Y}\).
Immediate and Near Wake Flow Patterns Behind Slotted Disks

The effect of spacing ratio on the near-wake regions immediately behind porous disks that consisted of multiple annular elements is investigated experimentally. Annular jets through individual slots merge into groups of highmomentum regions that displace a global recirculating region downstream. Multiple wake patterns result from the same overall conditions. Once the pattern forms, it remains nearly unchanged unless the e ow is disturbed. Compared to the e ow behind a solid disk, three-dimensional large-scale motions are suppressed downstream and the wake motions are more axisymmetric. The patterns of jet mergings are also axisymmetric and persistent. The mean and time-dependent large- and small-scale velocity e uctuations are characteristic of individual spacing ratios and e ow patterns, and they are analyzed and compared with e ow visualizations. The process of how the wake settles into a certain e ow pattern also is addressed.
Comparative n-gram analysis of whole-genome protein sequences

A current barrier for successful rational drug design is the lack of understanding of the structure space provided by the proteins in a cell that is determined by their sequence space. The protein sequences capable of folding to functional three-dimensional shapes of the proteins are clearly different for different organisms, since sequences obtained from human proteins often fail to form correct three-dimensional structures in bacterial organisms. In analogy to the question "What kind of things do people say?" we therefore need to ask the question "What kind of amino acid sequences occur in the proteins of an organism?" An understanding of the sequence space occupied by proteins in different organisms would have important applications for "translation" of proteins from the language of one organism into that of another and design of drugs that target sequences that might be unique or preferred by pathogenic organisms over those in human hosts. Here we describe the development of a biological language modeling toolkit (BLMT) for genome-wide statistical amino acid n-gram analysis and comparison across organisms (freely accessible at www.cs.cmu.edu/~blmt). Its functions were applied to 44 different bacterial, archaeal and the human genome. Amino acid n-gram distribution was found to be characteristic of organisms, as evidenced by (1) the ability of simple Markovian unigram models to distinguish organisms, (2) the marked variation in n-gram distributions across organisms above random variation, and (3) identification of organism-specific phrases in protein sequences that are greater than an order of magnitude standard deviations away from the mean. These lines of evidence suggest that different organisms utilize different "vocabularies" and "phrases", an observation that may provide novel approaches to drug development by specifically targeting these phrases. The results suggest that further detailed analysis of n-gram statistics of protein sequences from whole genomes will likely - in analogy to word n-gram analysis - result in powerful models for prediction, topic classification and information extraction of bilogical sequences.
Scale setting in top quark decays

Abstract We compute the O ( β 0 α s 2 ) QCD corrections to the Standard Model decay t → W + b as well as the non standard decay t → H + b . We then use our results to compute the BLM scale for these decays, and study the dependence of the BLM scale on the mass of the boson in the decay. We find that the BLM procedure gives extremely small scales when top decays into heavy bosons. When we try to improve the BLM scale by reexpressing rates as a functions of the top quark running mass, we find the BLM scale exhibits unnatural dependence on the boson mass, casting doubts on the applicability of the BLM procedure to these processes.
An Exploration of the Forward Premium Puzzle in Currency Markets

A standard empirical finding is that expected changes in exchange rates and interest rate differentials across countries are negatively related, implying that uncovered interest rate parity is violated in the data. This article provides new empirical evidence that suggests that violations of uncovered interest rate parity, and its economic implications, depend on the sign of the interest rate differentially. A framework related to term structure models is developed to account for the puzzling relationship between expected changes in exchange rates and interest rate differentials. Estimation results suggest that a particular term structure model can account for the puzzling empirical evidence. Article published by Oxford University Press on behalf of the Society for Financial Studies in its journal, The Review of Financial Studies.
New directions in synthetic solid state chemistry: chalcophosphate salt fluxes for discovery of new multinary solids

Abstract There have been recent developments in the application of molten polychalcophosphate salt fluxes for the synthesis of complex, multinary metal thiophosphate and selenophosphate compounds. New methodologies, new solids and the potential of polychalcophosphate fluxes have been discovered.
Characterizing the Universal Rigidity of Generic Frameworks

A framework is a graph and a map from its vertices to $${\mathbb E}^d$$ E d (for some $$d$$ d ). A framework is universally rigid if any framework in any dimension with the same graph and edge lengths is a Euclidean image of it. We show that a generic universally rigid framework has a positive semi-definite stress matrix of maximal rank. Connelly showed that the existence of such a positive semi-definite stress matrix is sufficient for universal rigidity, so this provides a characterization of universal rigidity for generic frameworks. We also extend our argument to give a new result on the genericity of strict complementarity in semidefinite programming.