cssi/SciSciGPT-SciSciNet huggingface dataset:
The optimal algorithm for asynchronous track-to-track fusion

Most existing track-to-track fusion (T2TF) algorithms for distributed tracking systems are given assuming that the local trackers are synchronized. However, in the real world, synchronization can hardly be achieved and local trackers usually work in an asynchronous fashion, where local measurements are obtained and local tracks are updated at different times with different rates. Communication delays between local trackers and the fusion center (FC) also cause delays in the arrival of the local tracks at the FC. This paper presents the optimal asynchronous T2TF algorithm for distributed tracking systems under the linear Gaussian (LG) assumption, which is also the linear minimum mean square error (LMMSE) fuser without the Gaussian assumption. The information configuration of asynchronous T2TF with partial information feedback (AT2TFpf) is used. This is the most practical configuration for AT2TF with time delays, since communication delays make full information feedback very complicated. To illustrate the algorithm, a basic scenario of the fusion of two asynchronous local tracks is used, where one is available at the FC with no delay and the other is transmitted from a local tracker with a time delay. The algorithm can be extended to scenarios with more than two local trackers. The optimal asynchronous T2TF algorithm is compared with the approximate algorithms proposed by Novoselsky (denoted as AT2TFpfApprA-C) and is shown to have performance benefit in consistency as well as in fusion accuracy. The drawback of the optimal fusion algorithm is that it has high communication and computational cost. Two new approximate algorithms, AT2TFpfApprD and AT2TFpfApprE, are also proposed which significantly reduce the cost of the optimal algorithm with little loss in fusion performance.
Data base: an emerging organizational function

A vignette of increasing frequency is for a manager with a problem to arrive in the EDP manager's office and ask for information required to solve his problem. The information required almost always cuts across computer applications and files of several functional areas. In the majority of the installations, the EDP manager is forced to flatly turn down the manager's request. He either cannot respond because the needed data is hopelessly locked up in existing poorly documented computer files, or because responding would throw the normal computer processing into upheaval.
Monitoring Rapid Chemical Communication in the Brain

Neurotransmitters are chemicals that are secreted by neurons and relay messages to target cells. The goal of in vivo electrochemistry is to provide a real-time view of neurotransmitters in the extracellular space of the brain. This may be done in brain slices or the intact brain of anesthetized animals to probe the basic functions that regulate neurotransmitter levels. In other experiments, the measurements need to be made in the brain of behaving animals so that correlations of neurotransmitter fluctuations and specific behaviors can be made. For the neurotransmitter dopamine this can be accomplished today by chemical sensing of this neurotransmitter with fast scan cyclic voltammetry (FSCV) at carbon-fiber microelectrodes. Dopamine is an important target because it is a central player in the brain ‘reward’ system, although its precise function is not understood. Proposed roles for dopamine in reward have included the mediation of hedonia (pleasure)1, a messenger of incentive salience (wanting)2, or an error signal that promotes the learning associated with goal-directed behavior3,4. These multiple interpretations of dopaminergic function have arisen because, until recently, a real-time view of dopamine and its actions in an awake, behaving animal was unavailable. At the same time, new electrochemical technologies are being developed to measure other neurotransmitter actions. Electrochemical approaches are well suited for this application because they allow a neurotransmitter to be measured with high time resolution, enabling its precise role in the execution of behavioral tasks to be investigated. In this review we will describe current methods to detect neurotransmitters and monitor their concentration dynamics within neural tissue. The requirements for these methods are quite stringent. They need to be sufficiently selective so that the measured responses are unequivocally due to a specific molecule. They need to be sufficiently sensitive that they can detect these substances in the physiological range. The best established methodologies are for dopamine, so the majority of the applications of the methods described herein will involve this neurotransmitter. As will be seen, the goals in measuring neurotransmitter functions are diverse. On one hand, investigators are unraveling the mechanisms that control neurotransmitter concentrations. These studies range from examining biochemical synthesis to metabolism. On the other hand, investigators are questioning how the neurotransmitter interacts with its receptors and what message it conveys. Yet a third major interest is the role of a neurotransmitter in specific behaviors. To obtain a complete view of neurotransmission and information processing, chemical sensors need to be combined with traditional neurochemical tools. We will illustrate this approach with some specific examples.
Catalytic Asymmetric Addition of Dialkylzinc Reagents to α-Aldiminoesters

The first catalytic, enantioselective addition of organozinc reagents to α-aldiminoesters is described. The use of a Lewis acid/Lewis base containing bifunctional catalyst preorganizes both reactive substrates to promote enantioselective addition over the racemic background reaction and alternative addition modes. Alcohol additives were found to enhance the enantioselection. The addition product was also found to cyclize with remaining substrate to provide imidazolidines.
A CONVENIENT, LARGE SCALE SYNTHESIS OF N-CBZ-(S-PHENYL)-L-CYSTEINE

Abstract N-Cbz-(S-phenyl)-L-cysteine (3) has been prepared on a multi-kilogram scale in high yield and optical purity from the β-lactone of N-Cbz-L-serine.
Minicomputer Applications In Automated Testing Of Electro-Optical Guidance Systems

An Automated Laser Seeker Performance Evaluation System (ALSPES) has been developed at the US Army Missile Research and Development Command (USAMIRADCOM) which utilizes a minicomputer to implement the control functions required to test electro-optical (E /0) guidance systems. Software programs have been written for a series of tests which fully evaluate E /0 seeker performance. Test conditions are fed into a CRT terminal and the minicomputer conducts a fully automated, "hands-off" test by varying such parameters as laser energy, target position and velocity, seeker position and angular rate, and time separation between targets. This paper discusses the types of automated tests performed, the electro-optical test equipment utilized and the layout of the test facility, the minicomputer to test equipment interface, and the cost savings resulting from the development of this automated test facility.
A review of Stata 8.1 and its time series capabilities

This paper is a review of the statistical package Stata, version 8.1, with special emphasis on its time series capabilities. The program which generates empirical results and graphics in the paper may also be downloaded. (This abstract was borrowed from another version of this item.)
A Markov‐switching approach to measuring exchange market pressure

This paper characterizes exchange market pressure (EMP) as a nonlinear Markov-switching phenomenon, and examines its dynamics in response to money growth and inflation over three regimes. The empirical results identify episodes of EMP in the Kyrgyz Republic and confirm the statistical superiority of the nonlinear regime-switching model over a linear VAR version in understanding EMP. The nonlinear empirical approach adequately characterizes the data generation process and yields results that are consistent with theoretical predictions, particularly the dampening effect of monetary contraction on depreciation pressure. During periods of appreciation pressure, however, the reverse policy option—monetary expansion—may not be efficient, particularly where PPP rather than UIP drives exchange rates. In addition, monetary expansion in such cases defeats the primary objective of monetary policy—price stability—and may exacerbate the instability. Copyright © 2010 John Wiley & Sons, Ltd.
New Class of Ruthenium Sulfide Clusters: Ru4S6(PPh3)4, Ru5S6(PPh3)5, and Ru6S8(PPh3)6

Reaction of RuCl2(PPh3)3 with S2- sources yields a family of phosphine-containing Ru−S clusters which have been characterized crystallographically and by MALDI-MS. Ru4S6(PPh3)4 (Ru−Ruav = 2.94 A) has idealized Td symmetry whereas Ru6S8(PPh3)6 (Ru−Ruav = 2.82 A) adopts the idealized Oh symmetry characteristic of Chevrel clusters. Ru5S6(PPh3)5 is formally derived by the addition of Ru(PPh3) to one face of Ru4S6(PPh3)4. In terms of its M−S connectivity, the Ru5S6 cluster resembles a fragment of the FeMo cluster in nitrogenase.
Control Augmented Structural Synthesis with Transient Response Constraints

An integrated approach to the optimum design of control augmented structural systems is presented in which structural variables and control variables are changed simultaneously during the design process. Constraints are imposed on peak transient dynamic displacements and accelerations, static displacements, natural frequencies, and control system effort. Side constraints imposed on structural member sizes and control system thresholds and actuator output forces insure the generation of physically meaningful designs. Example problems are presented which bring out the benefits of simultaneous treatment of both the structural design variables and the control design variables.
Superlattice geometry for gamma-ray lasers

Abstract The central problem to developing a graser—that pumping can inhibit or destroy the Mossbauer and Borrmann effects—can conceivably be mitigated by a superlattice geometry, into which collimated coherent transfer radiation is introduced to form a multiwave Borrmann (or anti-Borrmann) mode. Such a geometry is introduced, and its effects on pump intensity and lattice heating are discussed.
Silicon-rich H-ZSM-5 catalyzed conversion of aqueous ethanol to ethylene

Abstract A study of the H-ZSM-5 catalysis of the conversion of aqueous ethanol solutions to ethylene was carried out using zeolites having Si/Al atom ratios of 35 to 15,000. Rates of ethanol conversion dropped sharply as expected until a Si/Al ratio of about 500; at higher ratios the activity was maintained at a nearly constant level. All of the synthesized zeolites afforded 100% conversion of 20% aqueous ethanol when examined at 400 °C and space velocities (WHSV) of 3.4 hr−1 (based on the ethanol component). The ethylene selectivities steadily increased with the Si/Al ratio and reached a maximum of 99.6% using the silicon-rich H-ZSM-5 zeolites. The unusually high catalytic activity observed for the silicon-rich materials was attributed to especially reactive clusters of hydrogen-bonded silanols and was shown to be independent of the aluminum concentration.
Flares from the Tidal Disruption of Stars by Massive Black Holes

Tidal disruption flares are differentiated into two classes: those that are sub-Eddington and those that radiate near the Eddington limit. Flares from black holes above ~2×107 M☉ will generally not radiate above the Eddington limit. For a Schwarzschild black hole, the maximum bolometric luminosity of a tidal disruption is ~LEdd(5 × 107 M☉), which is substantially below the Eddington luminosities of the most massive disrupting black holes (~2×108 M☉). Bolometric corrections to the spectra of the brightest flares are found to be large, ~7.5 mag. Nevertheless, the brightest flares are likely to have absolute magnitudes in excess of -19 in V and -21 in U (in the absence of reddening). Because the spectra are so blue, K-corrections may actually brighten the flares in optical bands. If such flares are as frequent as believed, they may soon be detected in low- or high-redshift supernovae searches. The He II ionizing radiation produced in the flares may dominate that which is produced by all other sources in the centers of quiescent galaxies, creating a steady state, highly ionized, fossil nebula with an extent of ~1 kpc that may be observable in recombination lines.
Isomorphisms of genetic algorithms

Abstract We begin with the premise that the role of Holland schemata in directing genetic search should be granted both as a matter of empirical fact and as a natural consequence of the Schema Theorem. From this we conclude that schemata more general than Holland's can also be made to direct genetic search, and that a duality exists between problem representations and which schemata are relevant for their optimization. This duality provides a theoretical framework in which to interpret problem representations.
PREDICTING FAULT-PRONE SOFTWARE MODULES IN EMBEDDED SYSTEMS WITH CLASSIFICATION TREES

Embedded-computer systems have become essential to life in modern society. For example, the backbone of society's information infrastructure is telecommunications. Embedded systems must have highly reliable software, so that we avoid the severe consequences of failures, intolerable down-time, and expensive repairs in remote locations. Moreover, today's fast-moving technology marketplace mandates that embedded systems evolve, resulting in multiple software releases embedded in multiple products. Software quality models can be valuable tools for software engineering of embedded systems, because some software-enhancement techniques are so expensive or time-consuming that it is not practical to apply them to all modules. Targeting such enhancement techniques is an effective way to reduce the likelihood of faults discovered in the field. Research has shown software metrics to be useful predictors of software faults. A software quality model is developed using measurements and fault data from a past release. The calibrated model is then applied to modules currently under development. Such models yield predictions on a module-by-module basis. This paper examines the Classification And Regression Trees (CART) algorithm for building tree-based models that predict which software modules have high risk of faults to be discovered during operations. CART is attractive because it emphasizes pruning to achieve robust models. This paper presents details on the CART algorithm in the context of software engineering of embedded systems. We illustrate this approach with a case study of four consecutive releases of software embedded in a large telecommunications system. The level of accuracy achieved in the case study would be useful to developers of an embedded system. The case study indicated that this model would continue to be useful over several releases as the system evolves.
Are Residents’ Decisions Influenced More by a Decision Aid or a Specialist’s Opinion? A Randomized Controlled Trial

BACKGROUND Physicians are reluctant to use decision aids despite their ability to improve care. A potential reason may be that physicians do not believe decision aid advice.
Planar Molecular and Macromolecular Gradients: Preparation and Properties

We present a method for fabricating polymer brushes with a gradual variation of grafting density on solid substrates. The technique for generating such structures consists of: i) deposition of a molecular gradient of polymerization initiator on the solid substrate, and ii) polymerization from the substrate bound initiator centers (“grafting from”). In this publication we describe the preparation of gradient polymer brushes of poly(acryl amide) on silica-covered substrates. We show that the polymer density within the gradient polymer brush can be varied by controlling the polymerization time.
Nonplanar Crack Growth Using the Surface Integral Method

A surface integral formulation, based on representing a crack as a distribution of force dipoles, has been developed for modeling the propagation of a three-dimensional nonplanar fracture. The minimum strain energy density and maximum circumferential stress theories were used to determine the direction of crack growth. The extension of the fracture surface was based on the Paris law for fatigue. Remeshing of the fracture during growth was accomplished by adding a ring of elements to the existing mesh at the conclusion of each increment of crack growth. This promoted the efficiency of the algorithm by eliminating the need to recalculate the entire coefficient matrix. Use of the surface integral method, coupled with growth criteria, has yielded an accurate model for three-dimensional nonplanar crack growth under mixed mode loading conditions. The study of several penny-shaped precracks under mixed-mode loading conditions produced the expected growth trajectory, and compared favorably to existing two-dimensional, three-dimensional, and experimental results found in the literature.
HERA events, tevatron jets, and uncertainties on quarks at large x☆

Abstract The recently reported excess of events at HERA compared to QCD calculations impels us to examine all possible Standard Model explanations before invoking “new physics”. We explore the possibility of adding an unusual, but small, component of additional quarks at large x (beyond x > 0.75) as a way to increase the predicted SM cross-section in the HERA kinematic region by the QCD evolution feed-down effect. We describe various scenarios under which this can be achieved while maintaining good global fits to all established data sets. This implies a much larger SM uncertainty than commonly assumed. In addition, the modified parton distributions provide another possible mechanism to account for the CDF high- p t jet excess which occurs at similar x and Q 2 values.
Quiescent Radio Emission from Southern Late-Type M Dwarfs and a Spectacular Radio Flare from the M8 Dwarf DENIS 1048–3956

We report the results of a radio monitoring program conducted at the Australia Telescope Compact Array to search for quiescent and flaring emission from seven nearby Southern late-type M and L dwarfs. Two late-type M dwarfs, the M7 V LHS 3003 and the M8 V DENIS 1048-3956, were detected in quiescent emission at 4.80 GHz. The observed emission is consistent with optically thin gyrosynchrotron emission from mildly relativistic (~1-10 keV) electrons with source densities ne 109 cm-3 in B 10 G magnetic fields. DENIS 1048-3956 was also detected in two spectacular, short-lived flares, one at 4.80 GHz (peak fν = 6.0 ± 0.8 mJy) and one at 8.64 GHz (peak fν = 29.6 ± 1.0 mJy) approximately 10 minutes later. The high brightness temperature (TB 1013 K), short emission period (~4-5 minutes), high circular polarization (~100%), and apparently narrow spectral bandwidth of these events imply a coherent emission process in a region of high electron density (ne ~ 1011-1012 cm-3) and magnetic field strength (B ~ 1 kG). If the two flare events are related, the apparent frequency drift in the emission suggests that the emitting source either moved into regions of higher electron or magnetic flux density or was compressed, e.g., by twisting field lines or gas motions. This emission may be related to a recent optical flare from this source that exhibited indications of chromospheric mass motion. The quiescent fluxes from the radio-emitting M dwarfs are too bright to support the Gudel-Benz empirical radio/X-ray relations, confirming a trend previously noted by Berger et al. The violation of these relations is symptomatic of a divergence in magnetic emission trends at and beyond spectral type M7/M8, where relative X-ray and Hα emission drops precipitously while relative radio emission appears to remain constant or possibly increases. With an apparent decline in chromospheric/coronal heating, the origin of hot coronal plasmas around ultracool dwarfs remains uncertain, although external sources, such as accretion from a residual disk or tidally distorted companions, remain possibilities worth exploring.
Practice patterns in neonatal cardiopulmonary bypass.

Abstract This article reviews practice patterns of numerous congenital heart surgeons, as collected from surveys (the Congenital Heart Surgeon's Society) and from audience response at the American Association of Thoracic Surgery (May 2003) and the Society of Thoracic Surgeons (January 2004). The information shows that there are numerous practice patterns, with unanimity only in the use of cardioplegia, although the delivery, type, and timing of doses varies. Hypothermic circulatory arrest continues to be used by the majority of congenital heart surgeons, although strategies for delivery have evolved in a way that reflects research contributions over the past decade.
Quantum hair on black holes

A black hole may carry quantum numbers that are not associated with massless gauge fields, contrary to the spirit of the “no-hair” theorems. We describe in detail two different types of black-hole hair that decay exponentially at long range. The first type is associated with discrete gauge charge and the screening is due to the Higgs mechanism. The second type is associated with color magnetic charge, and the screening is due to color confinement. In both cases, we perform semiclassical calculations of the effect of the hair on local observables outside the horizon, and on black-hole thermodynamics. These effects are generated by virtual cosmic strings, or virtual electric flux tubes, that sweep around the event horizon. The effects of discrete gauge charge are nonperturbative in ħ, but the effects of color magnetic charge become ħ-independent in a suitable limit. We present an alternative treatment of discrete gauge charge using dual variables, and examine the possibility of black-hole hair associated with discrete global symmetry. We draw the distinction between primary hair, which endows a black hole with new quantum numbers, and secondary hair, which does not, and we point out some varieties of secondary hair that occur in the standard model of particle physics.
Renormalizability and quantum stability of the phase transition in rigid string coupled to Kalb-Ramond fields. II

Abstract Recently we have shown that a phase transition occurs in the leading approximation of the large-N limit in rigid strings coupled to long range Kalb-Ramond interactions. The disordered phase is essentially the Nambu-Goto-Polyakov string theory while the ordered phase is a new theory. In this letter (Paper I) we study the first sub-leading quantum corrections of the free rigid string and derive the renormalization group equation. We show that the theory is asymptotically free, thus the extrinsic curvature of the string drops out at large distance scales in the disordered phase. In the following letter (Paper II [Phys. Lett. B 351 (1995), next article) we generalize the results of this letter to the interacting theory of rigid strings with the long range Kalb-Ramond interactions. We derive the renormalized mass gap equation and obtain the renormalized critical line. Our main and final result is that the phase transition does indeed survive quantum fluctuations.
Reorientation of Rotating Fluid in Microgravity Environment With and Without Gravity Jitters

In a spacecraft design, the requirements of settled propellant are different for tank pressurization, engine restart, venting, or propellant transfer. The requirement to settle or to position liquid fuel over the outlet end of the spacecraft propellant tank prior main engine restart poses a microgravity fluid behavior problem. In this paper, the dynamical behavior of liquid propellant, fluid reorientation, and propellant resettling have been carried out through the execution of supercomputer CRAY X-MP to simulate the fluid management in a microgravity environment. Results show that the resettlement of fluid can be accomplished more efficiently for fluid in rotating tank than in nonrotating tank, and also better performance for gravity jitters imposed on fluid settlement than without gravity jitters based on the amount of time needed to carry out resettlement period of time between the initiation and termination of geysering.
View-invariant human activity recognition based on shape and motion features

Recognizing human activities from image sequences is an active area of research in computer vision. Most of the previous approaches on activity recognition focus on recognition from a single view and ignore the issue of view invariance, and they deal with recognizing a single activity. There are only few published algorithms for segmenting and recognizing complex activities that are composed of more than one activity. In this paper, we present a view invariant human activity recognition approach that uses both motion and shape information. An augmented vector of both optical flow features as well as eigen shape features is used to represent motion and shape of the body in the region of interest in each frame of the sequence. Each activity is represented by a set of hidden Markov models, where each model represents the activity from a different viewing direction, to realize the view invariance. Also, we present a voting-based approach to automatically and effectively segment and recognize complex activities. Experiments on two sets of video clips of different activities show that our method is effective.
Group 14 Homologues of Hydrocarbons

Experimental values of geometric parameters are compared with the results of theoretical calculations for saturated (alkane-like) compounds containing Si, Ge, Sn, and Pb, in addition to hydrogen and carbon. The objective is to evaluate the accuracy and efficiency of computational methods for general use in theoretical studies of saturated group 14 homologues. In this paper we report bond lengths obtained using MMFF (Merck Molecular Force Field) and the semiempirical PM3 method. Both procedures are found to provide useful, but only fair rectifications of experimental bond length data.
Factorization in one loop gauge theory

Abstract Factorization properties of one-loop gauge theory amplitudes have been used as checks on explicitly computed amplitudes and in the construction of ansatze for higher-point ones. In massless theories, such as QCD at high energies, infrared divergences complicate factorization. Here we prove that factorization in such theories is described by a set of universal functions. In particular, a proof of the universality of one-loop splitting functions as the momenta of two particles become collinear is presented. Factorization in multi-particle channels is also given. The discontinuity functions that appear in the splitting functions may also be used to obtain infrared divergent box integral functions from finite ones.
Improved actions of the staggered fermion

Abstract We have studied O(a 2 ) improved lattice QCD with the staggered fermion by using Symanzik's program. We find that there are 5 dimension-6 fermion bilinears and gauge operators. In addition, there are 10 four-fermion operators which are absent at the tree-level and tadpole-improved tree-level.
Ignition and structure of a laminar diffusion flame in a compressible mixing layer with finite rate chemistry

The ignition and structure of a reacting compressible mixing layer is considered using finite rate chemistry lying between two streams of reactants with different freestream speeds and temperatures. Numerical integration of the governing equations show that the structure of the reacting flow can be quite complicated depending on the magnitude of the Zeldovich number. An analysis of both the ignition a diffusion flame regimes is presented using a combination of large Zeldovich number asymptotics and numerics. This allows to analyze the behavior of these regimes as a function of the parameters of the problem.
Introductory Aerothermodynamics of Advanced Space Transportation Systems

The aerothermodynamic problems associated with hypervelocity flight at high altitudes (low ambient density) are considered. The physical phenomena are described and their severity in terms of aerodynamic heating for advanced space transportation systems are estimated. Flight domains corresponding to various physical phenomena are mapped. Approximate methods of analysis for conceptual studies are noted and preliminary results and estimates are presented. Problem areas that need both theoretical and experimental research are highlighted. The development of advanced computational codes that need to be prepared for use when approximate conceptual studies have defined advantageous configurations is discussed. Two advanced space transportation systems are considered: the aeroassisted orbital transfer vehicle concept and the small, rapid-response, manned, maneuverable concept that takes off from Earth or a conventional aircraft, enters a near-Earth orbit, and finally re-enters the atmosphere with lift and cross-range capability to land on an airstrip. Nomenclature g = gravitational constant GO = geosynchronous orbit k = catalycity coefficient p = pressure q = heating rate r = distance from the center of the Earth R = body nose radius, "equivalent body radius," surface reflectivity T = temperature U = velocity relative to the Earth's atmosphere V = inertial velocity or speed F = ratio of radiative flux to freestream energy flux A = shock standoff distance e = surface emissivity X = mean free path p = gas density a = Stephan-Boltzmann constant
Visually guided navigation

Rich sensory information, robust control strategies and proper representation of the environment are crucial for successful navigation of the mobile robot. We propose a model of the environment which is suitable for global navigation using visual sensing. At the lowest level of interaction of the robot with the environment we employ visual servoing techniques which facilitate robust local navigation by means of relative positioning. Further we demonstrate how to use these local control strategies in a global setting. The environment is represented in terms of place graph, where the nodes correspond to places and arcs have associated servoing strategies for moving from one place to another. The global navigation is expressed as a sequence of relative positioning tasks obtainable from the search of a place graph. The proposed model facilitates generation of motion plans which can be executed in a robust manner thanks to the presence of the sensory information in the feedback loop.
Photodichroic Silicate Glass Surface

The photodichroic silicate glass surface is a direct-read-after-write laser recording material which permits instant optical recording without processing of any kind. The required writing energy density at mega Hz rate and higher is 40 mj/cm2. An even better writing sensitivity is expected for a preconditioned glass surface which is yet to be demonstrated at mega Hz rates. The inherent resolution capability of this material is better than 2000 cycles/mm, which is consistent with the fine grain structure of the photodichroic silicate glass surface (grain size <0.02 pm). The photodichroic silicate glass surface can be pre-recorded with tracks of width 1µm or less. It is potentially a pinhole-free recording material due to the inherent homogeneity of the silicate glasses, and to the very small sizes of the photosensitive crystals, relative to the wavelength of light and the thickness of the photosensitive glass sur-face layer. The physical effect of recording is irreversible; yet the recorded spots or bits are erasable. The erased 1-bit can be distinguished easily from the 0-bit (of course, not distinguishable in the normal read mode), when necessary. There is also a mechanism to prevent erasing after recording and error corrections are completed. The writing is done with a polarized red light, and nondestructive read is done using a near infrared beam, with the recorded bits between crossed polarizers. The erasure is to re-expose with the write beam whose polarization direction has been rotated 45° with respect to the initial polarization exposure direction. In this manuscript, the physical effect of recording is discussed in detail, including the intensity dependent writing sensitivity, the threshold effect, and the relationships among observed spot size, contrast and the writing energy density. Recording in mega Hz rates as well as write-erase cycling are demonstrated.
Contact zones and hydrothermal systems as analogues to repository conditions

Abstract Radioactive waste isolation efforts in the U.S.A. are currently focused on examining basalt, tuff, salt and crystalline rock as candidate rock types to encompass waste repositories. As analogues to near-field conditions, the distributions of radio- and trace elements have been examined across contacts between these rocks and dikes and stocks that have intruded them. The intensive study of the Stripa quartz monzonite in Sweden has also offered the opportunity to observe the distribution of U and its daughters in groundwater and its relationship to U associated with fracture-filling and alteration minerals. Investigations of intrusive contact zones to date have included: (1) a Tertiary stock into Precambrian gneiss; (2) a stock into ash flow tuff; (3) a rhyodacite dike into Columbia River basalt, Washington, and (4) a kimberlite dike into salt. With respect to temperature and pressure, these contact zones may be considered “worst-case scenario” analogues. Results indicate that there has been no appreciable migration of radioelements from the more radioactive intrusives into the less radioactive country rocks, either in response to the intrusions or in the fracture-controlled hydrologic systems that developed following emplacement. In many cases, the radioelements are locked up in accessory minerals, suggesting that artificial analogues to these would make ideal waste forms. Emphasis should now shift to examination of active hydrothermal systems, studying the distribution of key elements in water, fractures, and alteration minerals under pressure and temperature conditions most similar to those expected in the near-field environment of a repository.
Fuzzy learning control for a flexible-link robot

There are two main drawbacks in fuzzy control: 1) the design of fuzzy controllers is usually performed in an ad hoc manner where it is often difficult to choose some of the controller parameters; and 2) the fuzzy controller constructed for the nominal plant may later perform inadequately if significant and unpredictable plant parameter variations occur. In this paper we illustrate these two problems on a two-link flexible robot testbed by: 1) developing, implementing, and evaluating a fuzzy controller for the robotic mechanism, and 2) illustrating that payload variations can have negative effects on the performance of a well designed fuzzy control system. Next, we show how to develop and implement a fuzzy model reference learning controller for the flexible robot and illustrate that it can automatically synthesize a rule-base for a fuzzy controller that will achieve comparable performance to the case where it was manually constructed, and automatically tune the fuzzy controller so that it can adapt to variations in the payload. >
Classifying cause of death after cancer surgery

A retrospective, single-center study was conducted to understand variation in mortality after elective cancer surgery. Fifty-two patients who died perioperatively after elective cancer resections (colon, esophageal, pancreatic, lung, gastric and liver) were identified. A methodology was developed and used during medical record review to capture the occurrence and chronology of 21 postoperative complications. Data were reviewed by 3 attending surgeons who assigned cause of death based on information from the entire clinical record. This methodology demonstrated good construct validity, with 81% agreement between cause of death assigned by expert review of data from the instrument and that assigned by expert review of the clinical records (kappa = 0.75, P < .005). Cause-specific mortality can be reliably and systematically measured after cancer surgery. Understanding variation in cause-specific mortality can inform future quality improvement efforts.
Matrix models for the black hole information paradox

We study various matrix models with a charge-charge interaction as toy models of the gauge dual of the AdS black hole. These models show a continuous spectrum and power-law decay of correlators at late time and infinite N, implying information loss in this limit. At finite N, the spectrum is discrete and correlators have recurrences, so there is no information loss. We study these models by a variety of techniques, such as Feynman graph expansion, loop equations, and sum over Young tableaux, and we obtain explicitly the leading 1/N 2 corrections for the spectrum and correlators. These techniques are suggestive of possible dual bulk descriptions. At fixed order in 1/N 2 the spectrum remains continuous and no recurrence occurs, so information loss persists. However, the interchange of the long-time and large-N limits is subtle and requires further study.
Evaluation of text data mining for database curation: lessons learned from the KDD Challenge Cup.

Motivation: The biological literature is a major repository of knowledge. Many biological databases draw much of their content from a careful curation of this literature. However, as the volume of literature increases, the burden of curation increases. Text mining may provide useful tools to assist in the curation process. To date, the lack of standards has made it impossible to determine whether text mining techniques are sufficiently mature to be useful. Results: We report on a Challenge Evaluation task that we created for the Knowledge Discovery and Data Mining (KDD) Challenge Cup. We provided a training corpus of 862 articles consisting of journal articles curated in FlyBase, along with the associated lists of genes and gene products, as well as the relevant data fields from FlyBase. For the test, we provided a corpus of 213 new (‘blind’) articles; the 18 participating groups provided systems that flagged articles for curation, based on whether the article contained experimental evidence for gene expression products. We report on the evaluation results and describe the techniques used by the top performing groups.
Photorefractive effect in BaTiO 3 : microscopic origins

We have used a number of experimental techniques to identify the photorefractive species in commercial samples of BaTiO3. We find that Fe impurities (in the Fe2+ and Fe3+ states) are the predominant photorefractive species. Techniques for optimizing the photorefractive properties of BaTiO3 are discussed.
Corruption, Inequality and Fairness ∗

Bigger governments raise the possibilities for corruption; more corruption may in turn raise the support for redistributive policies that intend to correct the inequality and injustice generated by corruption. We formalize these insights in a simple dynamic model. A positive feedback from past to current levels of taxation and corruption arises either when wealth originating in corruption and rent seeking is considered unfair, or when the ability to engage in corruption is unevenly distributed in the population. This feedback introduces persistence in the size of the government and the levels of corruption and inequality. Multiple steady states exist in some cases.
A versatile synthetic route to dehydrobenzoannulenes via in situ generation of reactive alkynes

This paper outlines the development of a protocol that allows in situ generation of unstable alkynes under Pd-catalyzed cross-coupling conditions. Cu-mediated intramolecular cyclization of the resultant α,ω-polyynes provides dehydrobenzoannulenes as singular species, in very good overall yields, and in a variety of topologies that are inaccessible by traditional routes or previously available in low yield only. In addition, we will discuss the solid-state structure and reactivity of these macrocycles, as well as the ability of the planar dehydrobenzoannulenes to support weak induced ring currents.
The social economics of ethical consumption: Theoretical considerations and empirical evidence

Abstract Recent years have seen rising discussion of ethical consumption as a means of stemming global warming, challenging unsavory business practices, and promoting other pro-social goals. This paper first lays out a conceptual framework for understanding the spread of ethical consumption, in which heterogeneous preferences and sensitivity to social norms feature centrally. It then presents empirical evidence from a well-known nationally representative survey on factors associated with tendencies to ‘buy ethically’. It is found that, ceteris paribus , people are more likely to buy ethically when others around them do too, consistent with a role of social norms in promoting ethical-consumption behaviors.
Recent Advances in Aldolase-Catalyzed Synthesis of Unnatural Sugars and Iminocyclitols

Facile chemoenzymatic methods for the synthesis of a variety of D- and L- iminocyclitols or L-sugars have been developed. The practicality of formerly reported methods using dihydroxyacetone phosphate (DHAP) aldolase was limited by the high cost and instability of DHAP. Here we discuss three strategies toward the facile synthesis of sugar analogues using DHA(P) aldolases from readily available non-phosphoryrated donor substrates. (1) Directed evolution of the L-rhamnulose 1-phosphate aldolase (RhaD) was employed to alter the donor substrate specificity of RhaD aldolase from DHAP to DHA. In vivo selection for the directed evolution using genetically engineered E. coli strain was constructed . (2) RhaD aldolase was found to accept non-phosphorylated dihydroxyacetone (DHA) as a donor substrate in the presence of borate. We applied this discovery to develop a practical one-step synthesis of L-fructose and two-step synthesis of L-iminocyclitols . (3) A one-pot synthesis was achieved using the recently discovered D-fructose 6-phosphate aldolse (FSA). FSA utilized DHA, hydroxyacetone, and 1-hydroxy-2-butanone as donor substrates to allow the synthesis of a variety of novel D-iminocyclitols in a concise fashion.
The first intermolecular 2+2 photocycloadditions of 2,5-cyclohexadien-1-ones to alkenes

Etude de la photo cycloaddition du methoxy-2 methyl-1 oxo-4 cyclohexadiene-2,5 carboxylate-1 de methyle et du cyclopentene conduisant principalement au methoxy-5 methyl-2 octahydro-2,3,3a,3b,4,7,7a,7b oxo-7 cyclopenta[3,4] cyclobuta[1,2] benzenecarboxylate-4 condense trans avec le cyclobutane
A generalized framework for analyzing time-space switched optical networks

The advances in photonic switching have paved the way for realizing all-optical time switched networks. The current technology of wavelength division multiplexing (WDM) offers bandwidth granularity that matches peak electronic transmission speed by dividing the fiber bandwidth into multiple wavelengths. However, the bandwidth of a single wavelength is too large for certain traffic. Time division multiplexing (TDM) allows multiple traffic streams to share the bandwidth of a wavelength efficiently. While introducing wavelength converters and time slot interchangers to improve network blocking performance, it is often of interest to know the incremental benefits offered by every additional stage of switching. As all-optical networks in the future are expected to employ heterogeneous switching architectures, it is necessary to have a generalized network model that allows the study of such networks under a unified framework. A network model, called the trunk switched network (TSN), is proposed to facilitate the modeling and analysis of such networks. An analytical model for evaluating the blocking performance of a class of TSNs is also developed. With the proposed framework, it is shown that a significant performance improvement can be obtained with a time-space switch with no wavelength conversion in multiwavelength TDM switched networks. The framework is also extended to analyze the blocking performance of multicast tree establishment in optical networks. To the best of our knowledge, this is the first work that provides an analytical model for evaluating the blocking performance for tree establishment in an optical network. The analytical model allows a comparison between the performance of various multicast tree construction algorithms and the effects of different switch architectures.
Broadband Noise Predictions for an Airfoil in a Turbulent Stream

Loading noise is predicted from unsteady surface pressure measurements on a NACA 0015 airfoil immersed in grid-generated turbulence. The time-dependent pressure is obtained from an array of synchronized transducers on the airfoil surface. Far field noise is predicted by using the time-dependent surface pressure as input to Formulation 1A of Farassat, a solution of the Ffowcs Williams - Hawkings equation. Acoustic predictions are performed with and without the effects of airfoil surface curvature. Scaling rules are developed to compare the present far field predictions with acoustic measurements that are available in the literature.
Blind joint equalization and multiuser detection for DS-CDMA in unknown correlated noise

The problem of blind demodulation of multiuser information symbols in an asynchronous multipath CDMA network in the presence of multiple-access interference (MAI), intersymbol interference (ISI), and ambient channel noise is considered. First, a discrete-time signal model for a multipath code-division multiple-access channel is developed, based upon which several linear receiver structures are defined. Blind channel-estimation methods exploiting the orthogonality between the signal and noise subspaces are then discussed. In particular, channel estimation in the presence of unknown correlated noise is considered. It is assumed that the receiver employs two well-separated antennas, such that the noise is spatially uncorrelated. Two subspace methods for estimating the channel response are examined, based on, respectively, the singular value decomposition (SVD) and the canonical correlation decomposition (CCD) of the cross-correlation matrix of the signals received by the two antennas. Simulation results show that the CCD-based method substantially outperforms the SVD-based method.
Sol-Gel Process for the Preparation of Ba2Ti9O20 and BaTi5O11

Barium titanate precursors with Ba/Ti ratio 2:9 and 1:5 were prepared by first hydrolyzing titanium alkoxide and then mixing the resulting titania sol with a barium alkoxide-methanol solution. After drying, the xerogels of the precursors of barium titanates were sintered at temperatures from 700°C (4 h) to 1200°C (110 h or longer). Characterization of the product was performed using X-ray diffraction and laser Raman spectroscopy. At 700°C, BaTi5O11 was formed from the 1:5 precursor and a two-phase mixture of BaTi2O5 and BaTi5O11 was formed from the 2:9 precursor. After prolonged heating at 1200°C, the latter mixture converted to a single-phase material, Ba2Ti9O20.