cssi/SciSciGPT-SciSciNet huggingface dataset:
An iterative SVD-Krylov based method for model reduction of large-scale dynamical systems

Abstract In this paper, we propose a model reduction algorithm for approximation of large-scale linear time-invariant dynamical systems. The method is a two-sided projection combining features of the singular value decomposition (SVD)-based and the Krylov-based model reduction techniques. While the SVD-side of the projection depends on the observability gramian, the Krylov-side is obtained via iterative rational Krylov steps. The reduced model is asymptotically stable, matches certain moments and solves a restricted H 2 minimization problem. We present modifications to the proposed approach for employing low-rank gramians in the reduction step and also for reducing discrete-time systems. Several numerical examples from various disciplines verify the effectiveness of the proposed approach. It performs significantly better than the q-cover [A. Yousouff, R.E. Skelton, Covariance equivalent realizations with applications to model reduction of large-scale systems, in: C.T. Leondes (Ed.), Control and Dynamic Systems, vol. 22, Academic Press, 1985, pp. 273–348; A. Yousouff, D.A. Wagie, R.E. Skelton, Linear system approximation via covariance equivalent realizations, Journal of Math. Anal. and Appl. 196 (1985) 91–115] and the least-squares [S. Gugercin, A.C. Antoulas, Model reduction of large scale systems by least squares, Linear Algebra Appl. 415(2–3) (2006) 290–321] methods that have a similar projection structure to the proposed method. Also, in terms of both the H 2 and H ∞ error measures, its performance is comparable to or sometimes better than that of balanced truncation. Moreover, the method proves to be robust with respect to the perturbations due to usage of approximate gramians.
Electrochromism in copper oxide thin films

Transparent thin films of copper(I) oxide prepared on conductive SnO2:F glass substrates by anodic oxidation of sputtered copper films or by direct electrodeposition of Cu2O transformed reversibly to opaque metallic copper films when reduced in alkaline electrolyte. In addition, the same Cu2O films transform reversibly to black copper(II) oxide when cycled at more anodic potentials. Copper oxide-to-copper switching covered a large dynamic range, from 85% and 10% photopic transmittance, with a coloration efficiency of about 32 cm2/C. Gradual deterioration of the switching range occurred over 20 to 100 cycles. This is tentatively ascribed to coarsening of the film and contact degradation caused by the 65% volume change on conversion of Cu to Cu2O. Switching between the two copper oxides (which have similar volumes) was more stable and more efficient (CE = 60 cm2/C), but covered a smaller transmittance range (60% to 44% T). Due to their large electrochemical storage capacity and tolerance for alkaline electrolytes, these cathodically coloring films may be useful as counter electrodes for anodically coloring electrode films such as nickel oxide or metal hydrides.
Free will: The elusive ideal

L'A. cherche a expliquer pourquoi sa conception de la liberte et de la volonte libre est distincte des autres conceptions traditionnelles et contemporaines, conceptions incompatibilistes et libertaristes y comprises
Heat Transfer Study of Staggered Thin Rectangular Blocks in a Channel Flow

In this study, fluid flow and heat transfer in two-dimensional staggered thin rectangular blocks in a channel flow heat exchanger is analyzed by the Finite Analytic Numerical Method. The heat exchanger consists of four staggered thin rectangular blocks at temperature T1 placed inside a channel which is formed by two plates maintained at constant temperature T0 . The fluid is considered to be incompressible and the flow laminar. Flow and heat transfer from the inlet of the heat exchanger to the outlet are simulated by solving Navier-Stokes and energy equations. Results were obtained for different block spacing and different size of the blocks. Computations were made for Reynolds numbers 100, 500, and 1,000, and Prandtl numbers 0.7 and 4.0. The results are presented in the form of velocity vector fields, isotherms, and local and global Nusselt numbers. The characteristics of the heat transfer and pressure drop in different block size and block separation are analyzed. The optimal length of separation between thin blocks and the optimal block length for maximum heat transfer are determined.
Stateless Crimes, Legitimacy, and International Criminal Law: The Case of Organ Trafficking

Organ trafficking and trafficking in persons for the purpose of organ transplantation are recognized as significant international problems. Yet these forms of trafficking are largely left out of international criminal law regimes and to some extent of domestic criminal law regimes as well. Trafficking of organs or persons for their organs does not come within the jurisdiction of the ICC, except in very special cases such as when conducted in a manner that conforms to the definitions of genocide or crimes against humanity. Although the United States Code characterizes trafficking as “a transnational crime with national implications,” (22 U.S.C. § 7101(b)(24) (2010)), trafficking is rarely prosecuted in domestic courts. It has thus functioned in practice largely as what might be judged a “stateless” offense, out of the purview of both international and national courts. Yet these forms of organ trafficking remain widespread—and devastating to those who are its victims. In this article, we begin by describing what is known about the extent of organ trafficking and trafficking in persons for the purpose of removal of organs. We then critically evaluate how and why such trafficking has remained largely unaddressed by both international and domestic criminal law regimes. This state of affairs, we argue, presents a missed chance for developing the legitimacy of international criminal law and an illustration of how far current international legal institutions remain from ideal justice.
Enhanced stability of polymeric micelles based on postfunctionalized poly(ethylene glycol)-b-poly(γ-propargyl L-glutamate): the substituent effect.

One of the major obstacles that delay the clinical translation of polymeric micelle drug delivery systems is whether these self-assembled micelles can retain their integrity in blood following intravenous (IV) injection. The objective of this study was to evaluate the impact of core functionalization on the thermodynamic and kinetic stability of polymeric micelles. The combination of ring-opening polymerization of N-carboxyanhydride (NCA) with highly efficient “click” coupling has enabled easy and quick access to a family of poly(ethylene glycol)-block-poly(γ-R-glutamate)s with exactly the same block lengths, for which the substituent “R” is tuned. The structures of these copolymers were carefully characterized by 1H NMR, FT-IR, and GPC. When pyrene is used as the fluorescence probe, the critical micelle concentrations (CMCs) of these polymers were found to be in the range of 10–7–10–6 M, which indicates good thermodynamic stability for the self-assembled micelles. The incorporation of polar side groups i...
The Interaction of Human and Physical Capital Accumulation: Evidence from Sub‐Saharan Africa*

I. INTRODUCTION While East Asian economic performance has given rise to a large literature studying its growth ‘miracle,’ Sub-Saharan Africa has attracted attention for exactly the opposite reason: the failure of the majority of the countries in the region to sustain per-capita income growth after the 1970s 1 .S everal studies of economic development in Sub-Saharan Africa (hereafter SSA) attribute low factor accumulation as a major cause of the ‘growth disaster.’ Collier and Gunning (1999) show that the stock of private capital per worker has fallen by twenty percent since 1980 and is now less than one half the level in South Asia, which they classify as the ‘next most capital scarce region in the world’. Human capital accumulation has also been slow in SSA; average educational attainment levels are consistently lower in SSA than in other developing regions 2 . The problem with blaming the SSA growth disaster on meager factor accumulation is that it begs the question of why factor accumulation has been so low. To a large extent, low levels of investment are a rational response to economic and political problems in the region, such as war, inflation, closed markets with distorted exchange rates, and a general lack of infrastructure. For example, Devarajan, Easterly, and Pack (2001) claim that the investment climate is so bad in the region that one could reasonably argue that investment is too high rather than too low. From this perspective, capital accumulation may be both low and optimal, given the negative incentives that investors face in the region.
Safety and Efficacy of Thrombolytic Therapy for Superior Vena Cava Syndrome

The experience at the Cleveland Clinic from 1982 to 1990 using thrombolytic therapy for superior vena cava (SVC) syndrome was retrospectively reviewed. Sixteen patients, 11 of whom had indwelling central venous catheters, were treated with either urokinase (n = 11) or streptokinase (n = 5). Either urokinase (4,400 U/kg bolus followed by 4,400 U/kg/h) or streptokinase (250,000 U bolus followed by 100,000 U/h) was used, and venograms were performed before and after. Overall, 56 percent of patients had complete clot lysis and relief of symptoms. Thrombolytic therapy was effective in eight (73 percent) of 11 patients receiving urokinase and one (20 percent) of five patients receiving streptokinase. Of those with a central venous catheter, eight (73 percent) of 11 patients were successfully lysed, whereas only one (20 percent) of five patients was successfully lysed if no catheter was present. If thrombolytic therapy was performed ≤ five days of symptom onset, seven (SS percent) of eight patients were successful, if thromobolytic therapy was performed > five days after symptom onset, two (25 percent) of eight patients were successful. Symptoms were relieved and the catheter was preserved in patients in whom thrombolytic therapy was effective. Factors predicting success were as follows: (1) the use of urokinase compared with streptokinase; (2) the presence of a central venous catheter; and (3) a duration of symptoms ≤ five days. (Chest 1991; 99:54–59)
Efficient catalyst turnover in the phosphitylation of alcohols with phosphoramidites

Abstract We report a method for catalytic phosphitylation utilizing phosphoramidites. Traditionally, this reaction is inefficient unless an excess of catalyst is present due to catalyst deactivation by an amine by-product. Isocyanate additives have been evaluated for scavenging the amine to facilitate catalyst turnover. A variety of alcohols and phosphoramidites were screened with 5 mol % catalyst. In the presence of additive, 83–97% conversion was achieved in contrast to 7–31% conversion without additive.
Testing, crime and punishment

Abstract The recent passage of the No Child Left Behind Act of 2001 solidified a national trend toward increased student testing for the purpose of evaluating public schools. This new environment for schools provides strong incentives for schools to alter the ways in which they deliver educational services. This paper investigates whether schools may employ discipline for misbehavior as a tool to bolster aggregate test performance. To do so, this paper utilizes an extraordinary data set constructed from the school district administrative records of a subset of the school districts in Florida during the 4 years surrounding the introduction of a high-stakes testing regime. It compares the suspensions of students involved in each of the 41,803 incidents in which two students were suspended and where prior test scores for both students are observed. While schools always tend to assign harsher punishments to low-performing students than to high-performing students throughout the year, this gap grows substantially during the testing window. Moreover, this testing window-related gap is only observed for students in testing grades. In summary, schools apparently act on the incentive to re-shape the testing pool through selective discipline in response to accountability pressures.
Axions, SN 1987A, and one-pion exchange.

Nucleon-nucleon, axion bremsstrahlung is the primary mechanism for axion emission from the nascent neutron star associated with SN 1987A, and the rate for this process has been calculated in the one pion exchange approximation (OPE). The axion mass limit which follows from SN 1987A, m sub a less than or approx equal to 10 to the -3 eV, is the most stringent astrophysical bound, and has received much scrutiny. It has been suggested that by using OPE to calculate the cross section for the analog process, pp yields pp + pi sup o, and comparing the result of the experimental data one can test the validity of this approximation, and further, that such a comparison indicates that OPE leads to a value for this cross section which is a factor of 30 to 40 too large. If true, this would suggest that the axion mass limit should be revised upward by a factor of approximately 6. The cross section for pp yields pp + pi sup o using OPE is carefully evaluated, and excellent agreement found (to better than a factor of 2) with the experimental data.
Improved Astrometry and Photometry for the Luyten Catalog. I. Bright Stars

We outline the construction of a refined version of the New Luyten Two-Tenths (NLTT) catalog of high proper motion stars, which will contain improved astrometry and photometry for the vast majority of the ~59,000 stars in NLTT. The bright end is constructed by matching NLTT stars to Hipparcos, Tycho-2, and Starnet; the faint end by matching to USNO-A and the Two Micron All Sky Survey (2MASS). In this first paper, we detail the bright-end matching procedure. We show that for the majority of stars in his catalog, Luyten measured positions accurate to 1'' even though he recorded his results much more coarsely. However, there is a long tail of position errors, with one error as large as 11?. Proper-motion errors for the stars with small position errors are 24 mas yr-1 (1 ?) but deteriorate to 34 mas yr-1 for stars with inferior positions. NLTT is virtually 100% complete for V 11.5 and |b| > 15?, but completeness in this magnitude range falls to ~75% at the Galactic plane. Incompleteness near the plane is not uniform, but is rather concentrated in the interval -80? < l < 20?, where the Milky Way is brightest.
Visualization of fluid flows in virtual environments

As computational methods keep improving and computational resources are entering a new era, the solution to physical problems is available at very high resolutions. Unfortunately, the computational resources that are available for interactive visualization of the solution at this resolution are not as accessible, hence the need to resort to alternative display techniques which can portray a better understanding of the solution, even at a lesser resolution. In this paper, we discuss methods for visualizing fluid data in a virtual environment. For steady-state data sets, we employ a feature-based streamline seeding technique. For time-variant data sets, we utilize view-dependent seeded pathlines. These methods address the aforementioned problems with high resolution data sets. In addition, we present the advantages of using virtual environments for flow visualization, and how analysts benefit from these advantages.© 2003 ASME
Optimal temporal product introduction strategies under valuation changes and learning

Consider a firm facing two consumer segments with differing valuations for quality. The demand is stationary and known, and consumers make repeat purchase over two time periods. However, once a premium product is introduced, the valuations of the consumers change in the next period. The firm derives a cost savings due to learning effect in the second period, the magnitude of which depends on the sales volume in the first period. Under such a situation, should a firm introduce a premium product before a basic product or the vice versa? Should it introduce two products simultaneously? When should a firm expand or consolidate its product line? What is the optimal product introduction strategy for a firm? Using a two-period stylized model we seek to answer these questions. We characterize the optimal product introduction strategy for the firm. We describe three easily calculable parameters that govern the optimal choice of the firm. The conditions under which a firm should expand or consolidate its product line are discussed. We study the effects of cost savings and customer valuation changes. We show that the dominated product strategies in absence of these effects can be a part of an optimal product strategy of a firm under valuation changes and cost savings. The managerial implications of the model are discussed.
Adaptive filtering for global interference cancellation and real-time recovery of evoked brain activity: a Monte Carlo simulation study

The sensitivity of near-infrared spectroscopy (NIRS) to evoked brain activity is reduced by physiological interference in at least two locations: 1. the superficial scalp and skull layers, and 2. in brain tissue itself. These interferences are generally termed as "global interferences" or "systemic interferences," and arise from cardiac activity, respiration, and other homeostatic processes. We present a novel method for global interference reduction and real-time recovery of evoked brain activity, based on the combination of a multiseparation probe configuration and adaptive filtering. Monte Carlo simulations demonstrate that this method can be effective in reducing the global interference and recovering otherwise obscured evoked brain activity. We also demonstrate that the physiological interference in the superficial layers is the major component of global interference. Thus, a measurement of superficial layer hemodynamics (e.g., using a short source-detector separation) makes a good reference in adaptive interference cancellation. The adaptive-filtering-based algorithm is shown to be resistant to errors in source-detector position information as well as to errors in the differential pathlength factor (DPF). The technique can be performed in real time, an important feature required for applications such as brain activity localization, biofeedback, and potential neuroprosthetic devices.
Designing large-scale supply chain linear programs in spreadsheets

Developing techniques to create a complete supply chain model across an entire product line.
Low-energy dynamics of string solitons

Abstract The dynamics of a class of fivebrane string solitons is considered in the moduli space approximation. The metric on moduli space is found to be flat. This implies that at low energies the solitons do not interact, and their scattering is trivial. The range of validity of the approximation is also briefly discussed.
Non-conservation of global charges in the Brane Universe and baryogenesis

Abstract We argue that global charges, such as baryon or lepton number, are not conserved in theories with the Standard Model fields localized on the brane which propagates in higher-dimensional space-time. The global-charge non-conservation is due to quantum fluctuations of the brane surface. These fluctuations create “baby branes” that can capture some global charges and carry them away into the bulk of higher-dimensional space. Such processes are exponentially suppressed at low-energies, but can be significant at high enough temperatures or energies. These effects can lead to a new, intrinsically high-dimensional mechanism of baryogenesis. Baryon asymmetry might be produced due either to “evaporation” into the baby branes, or creation of the baryon number excess in collisions of two Brane Universes. As an example we discuss a possible cosmological scenario within the recently proposed “Brane Inflation” framework. Inflation is driven by displaced branes which slowly fall on top of each other. When the branes collide inflation stops and the Brane Universe reheats. During this non-equilibrium collision baryon number can be transported from one brane to another one. This results in the baryon number excess in our Universe which exactly equals to the hidden “baryon number” deficit in the other Brane Universe.
Conformational collapse of surface-bound helical filaments

Chiral polymers are ubiquitous in nature and in the cellular context they are often found in association with membranes. Here we show that surface bound polymers with an intrinsic twist and anisotropic bending stiffness can exhibit a sharp continuous phase transition between states with very different effective persistence lengths as the binding affinity is increased. Above a critical value of the binding strength, determined solely by the torsional modulus and intrinsic twist rate, the filament can exist in a zero twist, surface bound state with a homogeneous stiffness. Below the critical binding strength, twist walls proliferate and function as weak or floppy joints that sharply reduce the effective persistence length that is measurable on long length scales. The existence of such dramatically different conformational states has implications for both biopolymer function in vivo and for experimental observations of such filaments in vitro.
Experiments on the stability of liquid films adjacent to supersonic boundary layers

Abstract : The stability of liquid films adjacent to supersonic streams was investigated experimentally and compared with analytical results. Linear theories predict that films adjacent to supersonic streams are much more unstable than those adjacent to subsonic streams. However, our supersonic experimental observations incidated that the liquid film was stable with no entrainment under all test conditions. These conditions included laminar and turbulent boundary layers, a variation in the liquid Reynolds number (Based on flow rate) from 1 to 200, and a variation in the liquid Reynolds number (based on flow rate) from 1 to 200, and a variation in the free-stream unit Reynolds number from 1600000/m to 110,000,000/m. These experimental observations can be explained by nonlinear theories which predicts that linear unstable disturbances do not grow indefinitely, but achieve steady-state amplitudes in the supersonic case. The different aspects of the observed wave behavior such as frequency, wavelength, and amplitude are discussed and compared with previous experimental observations and the nonlinear theories. (Author)
Validity of the nasometer measuring the temporal characteristics of nasalization.

Objective To examine the validity of the Nasometer (KayPENTAX, Lincoln Park, NJ) in measuring the temporal characteristics of nasalization by comparing the Nasometer measures to the measures from an external criterion procedure. Design Speech samples consisted of three rate-controlled nonsense syllables, which varied in their vowel compositions: /izinizi/, /azanaza/, and /uzunuzu/. Acoustic data were recorded simultaneously through the Nasometer and an external criterion procedure (a specialized microphone set that collected acoustic signals separately for the nasal and oral channels). Speech segment durations measured from the two instrumental conditions were compared on the Nasometer display and the Computerized Speech Lab (KayPENTAX, Lincoln Park, NJ) display. Five durational variables were measured: total utterance duration, nasal onset interval, nasal consonant duration, nasal offset interval, and total nasalization duration. Participants Fourteen normal adults who speak American English as their first language participated in the study. Results No significant differences were found between the measures from the Nasometer and those from an external criterion procedure in all the durational variables pertinent to nasalization. Different vowels, however, yielded significantly different patterns in these durational variables, in which the low vowel /a/ context revealed significantly longer total nasalization duration than did the high vowel /i/ and /u/ contexts. Conclusions The results suggest that the Nasometer can be used as a valid tool to measure the temporal characteristics underlying nasalization and confirm significant vowel effects on the temporal patterns of nasalization.
Efficient reasoning about action and change in the presence of incomplete information and its application in planning

Many domains that we wish to model and reason about are subject to change due to the execution of actions. Representing and reasoning about dynamic domains play an important role in AI because they serve as a fundamental basis for many applications, including planning, diagnosis, and modelling. Research in the field focuses on the development of formalisms for reasoning about action and change (RAC). Such a formalism normally consists of two components: a representation language and a reasoning mechanism. It has been well known in the field that two criteria for the success of a formalism are its expressiveness and efficiency. The former means that the representation language is rich enough to describe complicated domains; the latter implies the reasoning mechanism is computationally efficient, making it possible to be implemented on a machine. Besides, in daily life, we have to face the absence of complete information and thus any formalism should take this matter into account.
Ultra-compact nanoplasmonic splitter

We present novel designs and fabrication of ultra-compact coupler and 1×2 splitter using plasmonic waveguides. The coupling efficiency is 88% for the former one and 45% for each branch for the latter one.
Current Technologies, Economics, and Perspectives for 2,5‐Dimethylfuran Production from Biomass‐Derived Intermediates

Since the U.S. Department of Energy (DOE) published a perspective article that described the potential of the top ten biomass-derived platform chemicals as petroleum replacements for high-value commodity and specialty chemicals, researchers around the world have been motivated to develop technologies for the conversion of biomass and biomass-derived intermediates into chemicals and fuels. Among several biorefinery processes, the conversion of biomass carbohydrates into 2,5-dimethylfuran (DMF) has received significant attention because of its low oxygen content, high energy content, and high octane value. DMF can further serve as a petroleum-replacement, biorenewable feedstock for the production of p-xylene (pX). In this review, we aim specifically to present a concise and up-to-date analysis of DMF production technologies with a critical discussion on catalytic systems, mechanistic insight, and process economics, which includes sensitivity analysis, so that more effective catalysts can be designed. Special emphasis has been given to bifunctional catalysts that improve DMF yields and selectivity and the synergistic effect of the bifunctional sites. Process economics for the current processes and the scope for further improvement are discussed. It is anticipated that the chemistry detailed in this review will guide researchers to develop more practical catalytic processes to enable the economic production of bio-based DMF. Processes for the upgrade of DMF to pX are also described.
Adaptive Optimization and Systematic Probing of Infrastructure System Maintenance Policies under Model Uncertainty

We present an application of systematic probing for selecting optimal maintenance, repair, and reconstruction (MR&R) policies for systems of infrastructure facilities under model uncertainty. We use an open-loop feedback control approach, where the model parameters are updated sequentially after every inspection round. The use of systematic probing improves the convergence of the model parameters by ensuring that all permissible actions are applied to every condition state. The results of the parametric analyses demonstrate that the MR&R policies converge earlier when systematic probing is used. However, the savings in the expected total costs as a result of probing are minor, and are only realized when the optimal probing fractions are used. On the other hand, the additional costs incurred when the wrong probing fractions are used are significant. The major conclusion from this work is that state-of-the-art adaptive infrastructure management systems, that do not use probing, provide sufficiently close to optimal policies.
Reynolds-stress and dissipation-rate budgets in a turbulent channel flow

The budgets for the Reynolds stresses and for the dissipation rate of the turbulence kinetic energy are computed using direct simulation data of a turbulent channel flow. The budget data reveal that all the terms in the budget become important close to the wall. For inhomogeneous pressure boundary conditions, the pressure-strain term is split into a return term, a rapid term, and a Stokes term. The Stokes term is important close to the wall. The rapid and return terms play different roles depending on the component of the term. A split of the velocity pressure-gradient term into a redistributive term and a diffusion term is proposed, which should be simpler to model. The budget data is used to test existing closure models for the pressure-strain term, the dissipation rate, and the transport rate. In general, further work is needed to improve the models.
Evaluating the impedance broadbanding potential of antennas

One of the principal concerns of the aircraft antenna designer is to determine whether an antenna having some known terminal impedance characteristics can be compensated to meet a specified, voltage standing-wave ratio (VSWR)-bandwidth relation. Alternatively, the problem may be to select from among possible antenna configurations that one which possesses the greatest impedance broadbanding potential. In this paper the problem is examined by means of modern circuit theory. Antenna impedances are approximated by rational algebraic fractions and the impedances represented by these functions are treated analytically to determine the VSWR-bandwidth relationship which may be obtained by optimum compensation. The functions that can be considered by the techniques developed are sufficiently complex to adequately represent the basic impedance characteristics obtained with typical airborne flush-mounted antennas over a frequency range that causes the dimensions of the antenna to vary between a small fraction of a wavelength and approximately a wavelength. Examples are given.
Visualization of second order tensor fields and matrix data

We present a study of the visualization of 3-D second order tensor fields and matrix data. The general problem of visualizing unsymmetric real or complex Hermitian second order tensor fields can be reduced to the simultaneous visualization of a real and symmetric second order tensor field and a real vector field. As opposed to the discrete iconic techniques commonly used in multivariate data visualization, the emphasis is on exploiting the mathematical properties of tensor fields in order to facilitate their visualization and to produce a continuous representation of the data. We focus on interactively sensing and exploring real and symmetric second order tensor data by generalizing the vector notion of streamline to the tensor concept of hyperstreamline. We stress the importance of a structural analysis of the data field analogous to the techniques of vector field topology extraction in order to obtain a unique and objective representation of second order tensor fields.
Optimal auctions for correlated buyers with sampling

Cremer and McLean [1985] showed that, when buyers' valuations are drawn from a correlated distribution, an auction with full knowledge on the distribution can extract the full social surplus. We study whether this phenomenon persists when the auctioneer has only incomplete knowledge of the distribution, represented by a finite family of candidate distributions, and has sample access to the real distribution. We show that the naive approach which uses samples to distinguish candidate distributions may fail, whereas an extended version of the Cremer-McLean auction simultaneously extracts full social surplus under each candidate distribution. With an algebraic argument, we give a tight bound on the number of samples needed by this auction, which is the difference between the number of candidate distributions and the dimension of the linear space they span.
Dynamic modeling of exercise effects on plasma glucose and insulin levels.

Background: Regulation of plasma glucose concentration for type 1 diabetic patients is challenging, and exercise is an added complication. From a metabolic prospective, the significant exercise-induced effects are increased glucose uptake rate by the working tissues, increased hepatic glucose release to maintain overall glucose homeostasis, and decreased plasma insulin concentration. During prolonged exercise, glucose levels drop significantly because of the decrease in hepatic glucose production. With the long-term goal of developing a closed-loop insulin delivery system operating under various physiological conditions, it is necessary to develop a model that is capable of predicting blood glucose concentration at rest and during physical activity. Methods: A minimal model developed previously was extended to include the major effects of exercise on plasma glucose and insulin levels. Differential equations were developed to capture the exercise-induced dynamics of plasma insulin clearance and the elevation of glucose uptake and hepatic glucose production rates. The decreasing liver glucose output resulting from prolonged exercise was modeled using an equation depending on exercise intensity and duration. Results: The exercise model successfully captured the glucose and insulin dynamics during short- and long-term exercise. Model predictions of glucose and insulin dynamics during the postexercise recovery period were also consistent with literature data. Conclusion: The model successfully emulated the physiological effects of exercise on blood glucose and insulin levels. This extended model may provide a new disturbance test platform for the development of closed-loop glucose control algorithms.
Observed influence of riming, temperature, and turbulence on the fallspeed of solid precipitation

Forecasts of the amount and geographic distribution of snow are highly sensitive to a model's parameterization of hydrometeor fallspeed. Riming is generally thought to lead to particles with a higher mass and terminal velocity. Yet models commonly assume that heavily rimed particles such as graupel have a fixed density and that their settling speed is unaffected by turbulence in storms. Here we show automated measurements of photographed hydrometeor shape and fallspeed using a new instrument placed in Utah's Wasatch Mountain Range. The data show that graupel in low-turbulence conditions has a size-dependent fallspeed distribution with a mode near 1 m s−1, a result that is generally consistent with prior observations. However, the distributions are broadened by turbulence and there is a correspondence between particle density and air temperature. In high turbulence and at low temperatures, any sensitivity of fallspeed to particle size disappears.
Cooperative Behavior and the Frequency of Social Interaction

We report results from an experiment that examines play in an indefinitely repeated, 2-player Prisoner's Dilemma game. Each experimental session involves N subjects and a sequence of indefinitely repeated games. The main treatment consists of whether agents are matched in fixed pairings or matched randomly in each indefinitely repeated game. Within the random matching treatment, we vary the information that players have about their opponents. Contrary to a theoretical possibility suggested by Kandori (1992), a cooperative norm does not emerge in the treatments where players are matched randomly. On the other hand, in the fixed pairings treatment, the evidence suggests that a cooperative norm does emerge as players gain more experience.
Position tracking control of an induction motor via partial state feedback

Abstract This paper presents a rotor position tracking controller for an induction motor driving a robotic load. Using the nonlinear model of the induction motor and a nonlinear observer, local exponential rotor position tracking is obtained. The control only requires measurements of rotor position and stator current, while utilizing exact-model knowledge. Experimental results are included to illustrate the effectiveness of the proposed controller.
A REMARK ON LONG RANGE SCATTERING FOR THE NONLINEAR KLEIN–GORDON EQUATION

We consider the scattering problem for the nonlinear Klein–Gordon Equation with long range nonlinearity in one dimension. We prove that for all prescribed asymptotic solutions there is a solution of the equation with such behavior, for some choice of initial data. In the case the nonlinearity has the good sign (repulsive) the result hold for arbitrary size asymptotic data. The method of proof is based on reducing the long range phase effects to an ODE; this is done via an appropriate ansatz. We also find the complete asymptotic expansion of the solutions.
The Diversity-Multiplexing Tradeoff of the Dynamic Decode-and-Forward Protocol on a MIMO Half-Duplex Relay Channel

The diversity-multiplexing tradeoff of the dynamic decode-and-forward protocol is characterized for the half-duplex three-terminal (m, k, n)-relay channel where the source, relay and the destination terminals have m, k and n antennas, respectively. The tradeoff curve is obtained as a solution to a simple, two-variable, convex optimization problem which is explicitly solved in closed-form for certain special classes of relay channels, namely, the (1, k, 1) relay channel, the (n, 1, n) relay channel and the (2, k, 2) relay channel. Moreover, the tradeoff curves for a certain class of relay channels, such as the (m, k, n >; k) channels, are found to be identical to those for the decode-and-forward protocol for the full duplex channel while for other classes of channels they are marginally lower at high multiplexing gains. Our results also show that for some classes of relay channels and at low multiplexing gains the diversity orders of the dynamic decode-and-forward protocol are greater than those of the static compress-and-forward protocol which in turn is known to be tradeoff optimal over all static half duplex protocols. In general, the dynamic decode-and-forward protocol has a performance that is comparable to that of the static compress-and-forward protocol which, unlike the dynamic decode-and-forward protocol, requires global channel state information at the relay node. Its performance is also close to that of the decode-and-forward protocol over the full-duplex relay channel thereby indicating that the half-duplex constraint can be compensated for by the dynamic operation of the relay wherein the relay switches from the receive to the transmit mode based on the source-relay channel quality.
Synthesis, Opioid Receptor Binding, and Bioassay of Naltrindole Analogues Substituted in the Indolic Benzene Moiety

A series of analogues of the δ opioid receptor antagonist naltrindole (1) possessing a phenyl, phenoxy, or benzyloxy group at the 4‘-, 5‘-, 6‘-, or − 7‘-positions (4−15) and a 2-(2-pyridinyl)ethenyl group at the 5‘-position (16) on the indolic benzene ring were synthesized through Fischer indolization of naltrexone. Compounds 4−16 were evaluated for their affinities in opioid receptor binding assays in rat or guinea pig brain membranes and for their opioid antagonist and agonist activities in vitro on the guinea pig ileum (GPI) and mouse vas deferens (MVD) preparations. All of the compounds displayed δ selectivity in binding to the δ, μ, and κ opioid receptors. The binding potencies of most of the compounds at the δ, μ, and κ sites, however, were lower than that of 1. Among positional isomers, the 7‘-substituted compounds in general had higher affinities than 6‘-, 5‘-, or 4‘-substituted analogues, indicating that bulky groups are tolerated better at the 7‘-position than at other positions. The affinity of...
Analysis of modified SMI method for adaptive array weight control

The authors characterize the performance of the diagonally loaded sample matrix inverse (SMI) algorithm versus the number K of snapshots used in the covariance matrix estimate by providing O(1/K) statistics (bias and variance) of the array weights, output powers, and output power ratios such as signal to interference noise ratio (SINR) and INR. The approach accommodates wideband signals. Monte Carlo simulations verify the theoretical analysis. >
Effects of 10 Cigarette Smoke Condensates on Primary Human Airway Epithelial Cells by Comparative Gene and Cytokine Expression Studies

Cigarettes vary in tobacco blend, filter ventilation, additives, and other physical and chemical properties, but little is known regarding potential differences in toxicity to a smoker's airway epithelia. We compared changes in gene expression and cytokine production in primary normal human bronchial epithelial cells following treatment for 18 h with cigarette smoke condensates (CSCs) prepared from five commercial and four research cigarettes, at doses of approximately 4 microg/ml nicotine. Nine of the CSCs were produced under a standard International Organization for Standardization smoking machine regimen and one was produced by a more intense smoking machine regimen. Isolated messenger RNA (mRNA) was analyzed by microarray hybridization, and media was analyzed for secreted cytokines and chemokines. Twenty-one genes were differentially expressed by at least 9 of the 10 CSCs by more than twofold, including genes encoding detoxifying and antioxidant proteins. Cytochrome P450, family 1, subfamily A, polypeptide 1 (CYP1A1) and NAD(P)H dehydrogenase, quinone 1 (NQO-1) were selected for validation with quantitative real-time PCR (qRT-PCR) and Western blot analyses. NQO-1 expression determined with microarrays, qRT-PCR, and Western blotting differed among the CSC types, with good correlation among the different assays. CYP1A1 mRNA levels varied substantially, but there was little correlation with the protein levels. For each CSC, the three most induced and three most repressed genes were identified. These genes may be useful as markers of exposure to that particular cigarette type. Furthermore, differences in interleukin-8 secretion were observed. These studies lay the foundation for future investigations to analyze differences in the responses of in vivo systems to tobacco products marketed with claims of reduced exposure or reduced harm.
Parallel approximation algorithms for facility-location problems

This paper presents the design and analysis of parallel approximation algorithms for facility-location problems, including NC and RNC algorithms for (metric) facility location, k-center, k-median, and k-means. These problems have received considerable attention during the past decades from the approximation algorithms community, which primarily concentrates on improving the approximation guarantees. In this paper, we ask: Is it possible to parallelize some of the beautiful results from the sequential setting?.Our starting point is a small, but diverse, subset of results in approximation algorithms for facility-location problems, with a primary goal of developing techniques for devising their efficient parallel counterparts. We focus on giving algorithms with low depth, near work efficiency (compared to the sequential versions), and low cache complexity.
Mode shaping of a Nd:YAG laser with diffractive mirrors

Summary form only given. Conventional spherical mirror laser cavities produce spatial modes that are described by Hermite Gaussian functions. For some applications, however, the lowest-order Gaussian mode shape is not desired. In addition, the lasing threshold separation between this mode and higher-order modes is often small, leading to potential multi-mode operation. Laser cavities with non-spherical mirrors have been demonstrated that allow the designer to customize the fundamental laser mode and maximize the modal discrimination. In this paper, we show that a diffractive optical element can be used as a mode-synthesizing mirror (MSM) inside a Nd:YAG laser cavity. >
A Non-Traditional Vapor-Liquid-Solid Method for Bulk Synthesis of Semiconductor Nanowires

Multiple silicon nanowires were synthesized using large gallium pools and microwave plasma. Results showed that nanowires growing out of different sized large gallium drops show little variation in diameters, suggesting that our non-traditional technique can be used to synthesize bulk amounts of monodispersed nanowires out of thin films of molten gallium.
Identity matters: inter- and intra-racial disparity and labor market outcomes

Standard analysis of racial inequality incorporates racial classification as an exogenous binary variable. This approach obfuscates the importance of racial self-identity and clouds our ability to understand the relative importance of unobserved productivity-linked attributes versus market discrimination as determinants of racial inequality in labor market outcomes. Our examination of identity heterogeneity among African Americans suggests racial wage disparity is most consistent with weak colorism, while genotype disparity best describes racial employment differences. Further, among African Americans, the wage data are not consistent with the hypothesis that black-mixed race wage disparity can be explained by differences in unobserved productivity-linked productive attributes.
Evolving Wavelets Using a Coevolutionary Genetic Algorithm and Lifting

Finding a good wavelet for a particular application and type of input data is a difficult problem. Traditional methods of wavelet design focus on abstract properties of the wavelet that can be optimized analytically but whose influence on its real-world performance are not entirely understood. In this paper, a coevolutionary genetic algorithm is developed that searches the space of biorthogonal wavelets. The lifting technique, which defines a wavelet as a sequence of digital filters, provides a compact representation and an efficient way of handling necessary constraints. The algorithm is applied to a signal compression task with good results.
Common-Mode Voltage Reduction PWM Algorithm for AC Drives

The impact of common-mode voltage (CMV) generated by pulsewidth modulation (PWM) ac drives on motor bearings is well known. Several algorithms for CMV reduction have been proposed in the literature. While a few algorithms assume ideal switching and fall apart when nonidealities like inverter dead time are considered, some others are effective only in a limited operating range of the drive. In this paper, a previously proposed algorithm is modified for practical implementation to include compensation for dead-time and reflected-wave motor overvoltage stress while still producing output voltage waveforms with reduced common-mode content. Experimental results are provided to show the reduction in CMV over the entire operating range, with other performance attributes such as reflected-wave motor overvoltage that are identical to conventional space-vector PWM. The advantages of applying the algorithm to a fully regenerative ac drive are also demonstrated.
Propaganda and Conflict: Evidence from the Rwandan Genocide

This article investigates the role of mass media in times of conflict and state-sponsored mass violence against civilians. We use a unique village-level data set from the Rwandan genocide to estimate the impact of a popular radio station that encouraged violence against the Tutsi minority population. The results show that the broadcasts had a significant effect on participation in killings by both militia groups and ordinary civilians. An estimated 51,000 perpetrators, or approximately 10% of the overall violence, can be attributed to the station. The broadcasts increased militia violence not only directly by influencing behavior in villages with radio reception but also indirectly by increasing participation in neighboring villages. In fact, spillovers are estimated to have caused more militia violence than the direct effects. Thus, the article provides evidence that mass media can affect participation in violence directly due to exposure and indirectly due to social interactions. JEL Codes: D7, N4.