cssi/SciSciGPT-SciSciNet huggingface dataset:
When do in‐service teacher training and books improve student achievement? Experimental evidence from Mongolia

This study presents evidence from a randomized control trial (RCT) in Mongolia on the impact of in-service teacher training and books, both as separate educational inputs and as a package. The study tests for the complementarity of inputs and non-linearity of returns from investment in education as measured by students' test scores in five subjects. It takes advantage of a national-scale RCT conducted under the Rural Education and Development project. The results suggest that the provision of books, in addition to teacher training, raises student achievement substantially. However, teacher training and books weakly improve test scores when provided individually. Students whose teachers have received training and whose classrooms have acquired books improved their cumulative score (totaled across five tests) by 34.9 percent of a standard deviation, relative to a control group. Students treated only with books improved their total score by 20.6 percent of a standard deviation relative to a control group of students. On the other hand, extra teacher training did not have a statistically significant effect on the total test score. In addition, providing both inputs jointly improved test scores in most subjects, which was not the case when either input was provided individually. This study sheds light on the relevance of supplementing teacher training schemes with appropriate teaching materials in resource-poor settings. The policy implication is that isolated education investments, in settings where complementary inputs are missing, could deliver minimal or no return.
TiCl4 promoted three component coupling reaction: an efficient method for the substituted tetrahydropyrilidene acetates

The syntheses of substituted tetrahydropyrilidene acetates were accomplished by TiCl4 promoted carbon-carbon bond forming reaction of ethyl glyoxylate, 3,4-dihydro-2H-pyran and an appropriate carbon, oxygen or sulfur nucleophile. The reaction constitutes an efficient three component coupling process and the olefinic coupling product is dependent upon reaction temperature.
The Non-BPS black hole attractor equation

We study the attractor mechanism for extremal non-BPS black holes with an infinite throat near horizon geometry, developing, as we do so, a physical argument as to why such a mechanism does not exist in non-extremal cases. We present a detailed derivation of the non-supersymmetric attractor equation. This equation defines the stabilization of moduli near the black hole horizon: the fixed moduli take values specified by electric and magnetic charges corresponding to the fluxes in a Calabi Yau compactification of string theory. They also define the so-called double-extremal solutions. In some examples, studied previously by Tripathy and Trivedi, we solve the equation and show that the moduli are fixed at values which may also be derived from the critical points of the black hole potential.
Logarithmic vector-valued modular forms and polynomial-growth estimates of their Fourier coefficients

We establish (Theorem 3.6) polynomial-growth estimates for the Fourier coefficients of holomorphic logarithmic vector-valued modular forms.
Submicron wiring technology with tungsten and planarization

A versatile wiring technology has been developed which is suitable for high-density memory and multilevel logic applications. This fully integrated technology features CVD-tungsten (W) and planarization. Virtual W studs maximise density by reducing contact/via ground rules and by facilitating the use of thick insulators for minimum capacitance. Complementary insulator and W planarization eliminate steps and ease patterning. As a result, circuit performance is enhanced without sacrificing yield or reliability. The chosen materials and process combinations make possible aggressive metal pitch for DRAM, reliable space saving vertical studs for contact/via intensive SRAM, and provide vertical wiring for high-density multilevel logic. Device and reliability results are presented. >
Cooperative training for attribute-distributed data: Trade-off between data transmission and performance

This paper introduces a modeling framework for distributed regression with agents/experts observing attribute-distributed data (heterogeneous data). Under this model, a new algorithm, the iterative covariance optimization algorithm (ICOA), is designed to reshape the covariance matrix of the training residuals of individual agents so that the linear combination of the individual estimators minimizes the ensemble training error. Moreover, a scheme (Minimax Protection) is designed to provide a trade-off between the number of data instances transmitted among the agents and the performance of the ensemble estimator without undermining the convergence of the algorithm. This scheme also provides an upper bound (with high probability) on the test error of the ensemble estimator. The efficacy of ICOA combined with Minimax Protection and the comparison between the upper bound and actual performance are both demonstrated by simulations.
Making choices impairs subsequent self-control: A limited-resource account of decision making, self-regulation, and active initiative.

The current research tested the hypothesis that making many choices impairs subsequent self-control. Drawing from a limited-resource model of self-regulation and executive function, the authors hypothesized that decision making depletes the same resource used for self-control and active responding. In 4 laboratory studies, some participants made choices among consumer goods or college course options, whereas others thought about the same options without making choices. Making choices led to reduced self-control (i.e., less physical stamina, reduced persistence in the face of failure, more procrastination, and less quality and quantity of arithmetic calculations). A field study then found that reduced self-control was predicted by shoppers' self-reported degree of previous active decision making. Further studies suggested that choosing is more depleting than merely deliberating and forming preferences about options and more depleting than implementing choices made by someone else and that anticipating the choice task as enjoyable can reduce the depleting effect for the first choices but not for many choices.
A New QFT Design Method for SISO Cascaded-Loop Design

A quantitative feedback theory (QFT) design method for SISO cascaded-loop design which is different from the conventional inner-outer procedure and the outer-inner procedure is proposed in this paper. The desired uncertainty of the inner loop after closure is prescribed as a design specification before designing the inner controller, which is done by introducing an appropriate weight function. The inner loop design is therefore transferred into a sensitivity reduction problem. Then, the outer loop design becomes that of a plant with mixed uncertainty which can be carried out as usual. In this method, the weight function is an important design factor, which actually allocates the control burden between the inner and outer controllers. This method not only removes the arbitrariness in the closure of the inner loop in the inner-outer procedure, but also alleviates unnecessary iterations in the outer-inner procedure, which therefore could reduce the outer controller bandwidth drastically as demonstrated in two examples.
Minimum distance: a method for partitioning recurrences for multiprocessors

Parallel execution of nonvectorizable uniform recurrences is considered. When naively scheduled, such recurrences could create unacceptable communication and synchronization on a multiprocessor. The minimum-distance method partitions such recurrences into totally independent computations without increasing redundancy or perturbing numerical stability. The independent computations are well suited for execution on a multiprocessor, but they may not utilize all available processors. How extra processors can be applied to the independent computations is addressed. The methods are especially attractive for multiprocessors comprised of clusters. >
Update: Consequences of Abnormal Fetal Growth

Intrauterine growth restriction (IUGR) is prevalent worldwide and affects children and adults in multiple ways. These include predisposition to type 2 diabetes mellitus, the metabolic syndrome, cardiovascular disease, persistent reduction in stature, and possibly changes in the pattern of puberty. A review of recent literature confirms that the metabolic effects of being born small for gestational age are evident in the very young, persist with age, and are amplified by adiposity. Furthermore, the pattern of growth in the first few years of life has a significant bearing on a person's later health, with those that show increasing weight gain being at the greatest risk for future metabolic dysfunction. Treatment with exogenous human GH is used to improve height in children who remain short after being small for gestational age at birth, but the response of individuals remains variable and difficult to predict. The mechanisms involved in the metabolic programming of IUGR children are just beginning to be explored. It appears that IUGR leads to widespread changes in DNA methylation and that specific "epigenetic signatures" for IUGR are likely to be found in various fetal tissues. The challenge is to link such alterations with modifications in gene expression and ultimately the metabolic abnormalities of adulthood, and it represents one of the frontiers for research in the field.
Advanced image processing of aerial imagery

Aerial imagery of the Earth is an invaluable tool for the assessment of ground features, especially during times of disaster. Researchers at NASA's Langley Research Center have developed techniques which have proven to be useful for such imagery. Aerial imagery from various sources, including Langley's Boeing 757 Aries aircraft, has been studied extensively. This paper discusses these studies and demonstrates that better-than-observer imagery can be obtained even when visibility is severely compromised. A real-time, multi-spectral experimental system will be described and numerous examples will be shown.
Studies on the Biginelli reaction: a mild and selective route to 3,4-dihydropyrimidin-2(1H)-ones via enamine intermediates

Abstract l -Proline methyl ester hydrochloride was found to be an effective catalyst for assembling (±)-dihydropyrimidinones under mild conditions. Mechanistic insights into the useful selectivity elements of this amine-catalyzed process are also reported.
Ruthenium-Catalyzed Cycloadditions of 1-Haloalkynes with Nitrile Oxides and Organic Azides: Synthesis of 4-Haloisoxazoles and 5-Halotriazoles

(Cyclopentadienyl)(cyclooctadiene) ruthenium(II) chloride [CpRuCl(cod)] catalyzes the reaction between nitrile oxides and electronically deficient 1-choro-, 1-bromo-, and 1-iodoalkynes leading to 4-haloisoxazoles. Organic azides are also suitable 1,3-dipoles, resulting in 5-halo-1,2,3-triazoles. These air-tolerant reactions can be performed at room temperature with 1.25 equivalents of the respective 1,3-dipole relative to the alkyne component. Reactive 1-haloalkynes include propiolic amides, esters, ketones, and phosphonates. Post-functionalization of the halogenated azole products can be accomplished by using palladium-catalyzed cross-coupling reactions and by manipulation of reactive amide groups. The lack of catalysis observed with [Cp*RuCl(cod)] (Cp* = pentamethylcyclopentadienyl) is attributed to steric demands of the Cp* (η(5)-C5Me5) ligand in comparison to the parent Cp (η(5)-C5H5). This hypothesis is supported by the poor reactivity of [(η(5)-C5Me4CF3)RuCl(cod)], which serves as a an isosteric mimic of Cp* and as an isoelectronic analogue of Cp.
An Incentive-Compatibility Approach to the Problem of Monitoring a Bureau

An incentive-compatibility framework for regulating a monopolist with unknown costs is applied to the sponsor’s problem of monitoring a bureau. Following Mueller (1989), the bureau does not make take-it-or-leave-it budget proposals to the sponsor. Rather, the bureau must announce a marginal cost per unit of output to the sponsor. Given that report, the sponsor chooses a price that it will pay to the bureau for each unit of output, and the sponsor chooses the level of output as well. The analysis reveals the price per unit of output that the sponsor must pay to the bureau to maximize social welfare.
Timing- and crosstalk-driven area routing

We present a timing- and crosstalk-driven router for the chip assembly task that is applied between global and detailed routing. Our new approach aims to process the crosstalk and timing constraints by ordering nets and tuning wire spacing in a quantitative way. The new approach fits between global routing and detailed routing along the physical design flow. It is the first to address the timing- and crosstalk-driven area routing problem using crosspoint assignment prior to the detailed routing stage, in contrast to the most previous approaches applied in the post-detailed routing stage. Our new approach enjoys a larger optimization solution space than the previous approaches whose solution space is highly limited by routed geometric constraints. Based on the global routing information, our graph-based optimizer preroutes wires on the global routing grids incrementally. The graph-based optimizer has two stages, net order assignment and space relaxation. A quick capacitance extraction and Elmore delay calculator considering signal switching activities are implemented to find the timing of critical nets and to provide the timing slack database of critical nets. As the graph-based algorithm proceeds, the path delay of critical nets and the timing slack database are updated. During the optimization process, it only optimizes the timing critical paths with negative slack values. The experimental results show a 5%-16% delay reduction for MCNC macrocell benchmark circuits for a 0.25 /spl mu/m process for wire geometric ratio (height/width)=1.0, against a 25% delay reduction if there is infinite space around each metal wire on the same layer.
Adinkras for mathematicians

Adinkras are graphical tools created for the study of supersymmetry representations. Besides having in- herent interest for physicists, the study of adinkras has already shown connections with coding theory and Clifford algebras. Furthermore, adinkras offer many natural and accessible mathematical problems of combinatorial nature. We present the foundations for a mathematical audience, make new connections to other fields (homological algebra, poset theory, and polytopes), and solve some of these problems. Original results include the enumeration of all hyper- cube adinkras through dimension 5, the enumeration of odd dashings of adinkras for any dimension, and a connection between rankings and the chromatic polynomial for certain graphs. R´ esum´ e.
Tracking and Disturbance Rejection of MIMO Nonlinear Systems with PI Controller

We study tracking and disturbance rejection of a class of MIMO nonlinear systems with linear proportional plus integral (PI) compensator. Roughly speaking, we show that if the given nonlinear plant is exponentially stable and has a strictly increasing dc steady-state I/O map, then a simple PI compensator can be used to yield a stable unity-feedback closed-loop system which asymptotically tracks reference inputs that tend to constant vectors and asymptotically rejects disturbances that tend to constant vectors.
Perfectly meager sets and universally null sets

We will show that there is no ZFC example of a set distinguishing between universally null and perfectly meager sets.
Compton scattering at the NLC and large extra dimensions

We study Compton scattering, {gamma}e {yields} {gamma}e, in the context of the recent proposal for Weak Scale Quantum Gravity (WSQG) with large extra dimensions. It is shown that, with an ultraviolet cutoff M{sub S} {approx} 1 TeV for the effective gravity theory, the cross section for this process at the Next Linear Collider (NLC) deviates from the prediction of the Standard Model significantly. Our results suggest that, for typical proposed NLC energies and luminosities, WSQG can be tested in the range 4 TeV {approx}< M{sub S} {approx}< 16 TeV, making {gamma}e {yields} {gamma}e an important test channel.
Researchers Outside APC-Financed Open Access

The article processing charge (APC) financed Open Access is a publication model that provides immediate and free access to scientific articles. More than half of the world’s Open Access articles ar...
Real versus Complex Robustness Margin Continuity as a Smooth versus Holomorphic Singularity Problem

Abstract It is well known that the real robustness margin can be discontinuous, while the complex robustness margin is always continuous relative to problem data. Using some concepts from set-valued analysis, continuity of μ can be viewed as structural stability of the neutral stability region. From this point of view, the crucial issue is whether 0 + j0 is a critical value of the return difference map. This paper shows that the discrepancy between real and complex cases is due to the additional holomorphic property of the Nyquist return difference mapping of the complex μ-function. The critical points of the Nyquist map in the complex case are at most finite in number; in contrast, the critical points of the Nyquist map of the real smooth case form, generically, a curve. Furthermore and more importantly, in the complex case, even when 0 + j0 is critical, the stability crossover is continuously deformed under the variation of “certain” parameters, while in the real case, the crossover could sustain a catastrophic change.
From refuge to refugee: the African case.

Human security and environmental security often reinforcing can be at odds. One instance arises when greenlining the creation or expansion of relatively exclusionary protected areas leads to the mass displacement of local communities and the creation of a new variant of environmental refugees. The present research employs several methods to estimate the magnitude of environmental refugees in Africa and suggests that they number in the millions. Country-specific case studies are offered to lend historical context to these estimates. Environmentally oriented land reform is proposed as a partial mitigation for the social side effects of greenlining and is briefly described in African and other settings. (authors)
Drop on demand in a microfluidic chip

In this work, we introduce the novel technique of in-chip drop on demand, which consists in dispensing picoliter to nanoliter drops on demand directly in the liquid-filled channels of a polymer microfluidic chip, at frequencies up to 2.5 kHz and with precise volume control. The technique involves a PDMS chip with one or several microliter-size chambers driven by piezoelectric actuators. Individual aqueous microdrops are dispensed from the chamber to a main transport channel filled with an immiscible fluid, in a process analogous to atmospheric drop on demand dispensing. In this paper, the drop formation process is characterized with respect to critical dispense parameters such as the shape and duration of the driving pulse, and the size of both the fluid chamber and the nozzle. Several features of the in-chip drop on demand technique with direct relevance to lab-on-a-chip applications are presented and discussed, such as the precise control of the dispensed volume, the ability to merge drops of different reagents and the ability to move a drop from the shooting area of one nozzle to another for multistep reactions. The possibility to drive the microfluidic chip with inexpensive audio electronics instead of research-grade equipment is also examined and verified. Finally, we show that the same piezoelectric technique can be used to generate a single gas bubble on demand in a microfluidic chip.
On Adaptive BICM with Finite Block-Length and Simplified Metrics Calculation

In this paper we present a novel performance analysis of bit-interleaved coded modulation (BICM) over AWGN channel for different modulation schemes considering a finite block length and suboptimal metrics calculation. Using the known BICM capacity analysis as well as the Gallager bound, we show that among many known modulations, only three M-ary quadrature amplitude modulation (QAM) are necessary to ensure the maximization of the channel capacity. We analyze the maximum throughput and the switching thresholds of the system, and we compare the theoretical analysis with simulation results of practical strong codes, i.e., turbo codes. We show that if the modulation and code are well adapted, the optimal throughput decreases by less than 1% when suboptimal metrics are used. We show also, that the turbo codes throughput is within 1.5 dB of the new bound, and the SNR switching thresholds, are shifted by 1.5 dB with respect to the theoretical analysis.
IDENTIKIT 1: A MODELING TOOL FOR INTERACTING DISK GALAXIES

By combining test-particle and self-consistent techniques, we have developed a method to rapidly explore the parameter space of galactic encounters. Our method, implemented in an interactive graphics program3This software is available at http://www.ifa.hawaii.edu/faculty/barnes/research/identikit/., can be used to find the parameters required to reproduce the observed morphology and kinematics of interacting disk galaxies. We test this system on an artificial data set of 36 equal-mass merging encounters, and show that it is usually possible to reproduce the morphology and kinematics of these encounters and that a good match strongly constrains the encounter parameters.
Total synthesis of seco-lateriflorone

Abstract A convergent strategy toward the synthesis of lateriflorone ( 5 ) is described. Our approach is based on biosynthetic considerations and draws on a sequence of prenylation, oxygenation and Claisen reactions for the construction of chromenequinone 6 , and a tandem Claisen/Diels–Alder reaction cascade for the synthesis of caged tricycle 7 . Union of fragments 6 and 7 led to the synthesis of seco-lateriflorone ( 49 ).
Compression Precracking Methods to Generate Near-Threshold Fatigue-Crack-Growth-Rate Data

Abstract This paper summarizes some of the fatigue-crack-growth-rate data generated in the threshold and near-threshold regimes on two aluminum alloys (7075-T651, 7075-T7351), a titanium alloy (Ti–6Al–4V β-STOA), a high-strength 4340 steel and a nickel-based superalloy (Inconel-718) using compression precracking constant-amplitude (CPCA), compression precracking load-reduction (CPLR), and the ASTM E-647 load-reduction (LR) test methods. Tests were conducted over a range in stress ratios ( R = 0.1, 0.4 and 0.7) on compact specimens. One of the aluminum alloys (T651) and the 4340 steel showed very little difference between the methods; however, the other three materials showed significant differences with the compression precracking test methods giving lower thresholds and faster crack-growth rates than the load-reduction test method. Materials that have shown significant differences exhibited either rough crack-surface profiles (7075-T7351, Ti–6Al–4V β-STOA) or produced fretting debris along the crack surfaces in the threshold and near-threshold regimes (Inconel-718).
Workshop on designing and teaching information security curriculum

One of the continuing challenges facing the technology industry is the security and protection of the information contained within automated information systems. Advances in information security (InfoSec) have been unable to keep pace with advances in computing in general. One of the recognized ways to combat the threat to information systems is education needed to prepare students for employment creating a secure and ethical computing environment.
IDENTIFICATION OF THE BINARY CHOICE MODEL WITH MISCLASSIFICATION

Misclassification in binary choice (binomial response) models occurs when the dependent variable is measured with error, that is, when an actual “one” response is sometimes recorded as a zero and vice versa. This paper shows that binary response models with misclassification are semiparametrically identified, even when the probabilities of misclassification depend in unknown ways on model covariates and the distribution of the errors is unknown.
Reactions of 3H-1,2-benzodithiol-3-one 1-oxide with amines and anilines

Abstract Reaction of 3 H -1,2-benzodithiol-3-one 1-oxide with primary amines or anilines provides reasonable yields (40–70%) of the corresponding 1,2-benzisothiazolin-3(2 H )-ones. These reactions may have relevance to the biological chemistry of 1,2-dithiolan-3-one 1-oxides and also offer a new method for the preparation of certain 1,2-benzisothiazolin-3(2 H )-ones.
Audit Committee Independence and Disclosure: choice for financially distressed firms

This study examines the relation between audit committee independence and disclosure choice for financially distressed US firms. The tenor of both the financial statement notes and Management Discussion and Analysis (MD&A) is considered. For firms experiencing financial distress, there is a significant positive relation between the percentage of affiliated directors on the audit committee and the optimism of the going-concern discussion in both the notes and the MD&A. These results add to the growing body of literature documenting a relation between audit committee independence and financial reporting quality.
A shift-register-based QCA memory architecture

A quantum-dot cellular automata (QCA) design of an nxm-bit, shift-register-based memory architecture is presented. The architecture maintains data at a stable conformation, which is contrary to traditional data in-motion concept for QCA architectures. The memory architecture is based on an existing dual-phase-synchronized, line-based, one-bit QCA memory cell building block that provides size and latency improvements over other known one-bit memory cells through its novel clocking scheme. Read/write latencies up to ∼2X lower than the existing tile-based architecture with three-phase, line-based memory cells are obtained. Simulations with QCADesigner and HDLQ are performed on a sample 4x8 bit memory architecture implementation.
Accounting for Private Information

We study the quantitative properties of constrained e¢ cient allocations in an environment where risk sharing is limited by the presence of private information. We consider a life cycle version of a standard Mirrlees economy where shocks to labor productivity have a component that is public information and one that is private information. The presence of private shocks has important implications for the age pro…les of consumption and income. First, they introduce an endogenous dispersion of continuation utilities. As a result, consumption inequality rises with age even if the variance of the shocks does not. Second, they introduce an endogenous rise of the distortion on the marginal rate of substitution between consumption and leisure over the life cycle. This is because, as agents age, the ability to properly provide incentives for work must become less and less tied to promises of bene…ts (through either increased leisure or consumption) in future periods. Both of these features are also present in the data. We look at the data through the lens of our model and estimate the fraction of labor productivity that is private information. We …nd that for the model and data to be consistent, a large fraction of shocks to labor productivities must be private information.
The effect of self field on the critical current determination of multifilamentary superconductors

In determining the short sample critical current of conductors of large cross section or high current density, the self-field produced by the transport current must be taken into account to obtain a true value for the critical current. A simple model calculation for determining this effect is described. Measurements on wires, cables, and monoliths show the validity and self-consistency of the procedures. >
Sequential Entry in Many-to-one Matching Markets

We study sequential bargaining in many-to-one matching markets. We show that there is an advantage to entering late in the market, and that the last agent to enter the market will receive his or her best partner in a stable matching, extending the results of Blum and Rothblum (J Econ Theory 103(2):429–443, 2002) and Cechlarova (Randomized matching mechanism revisited. Mimeo, Safarik University, 2002) for the marriage model. We also discuss the relation between sequential bargaining and a possible alternative formulation based on the NTU Shapley value.
An improved switching converter model using discrete and average techniques

The nonlinear modeling and analysis of dc-dc converters has been done by averaging and discrete-sampling techniques. The averaging technique is simple, but inaccurate as the modulation frequencies approach the theoretical limit of one-half the switching frequency. The discrete technique is accurate even at high frequencies, but is very complex and cumbersome. An improved model is developed by combining the aforementioned techniques. This new model is easy to implement in circuit and state variable forms and is accurate to the theoretical limit.
Optimal wire sizing and buffer insertion for low power and a generalized delay model

We present efficient, optimal algorithms for timing optimization by discrete wire sizing and buffer insertion. Our algorithms are able to minimize a cost function subject to given timing constraints; we focus on minimization of dynamic power dissipation, but the algorithm is also easily adaptable to, for example, area minimization. In addition, the algorithm efficiently computes the complete, optimal power-delay trade-off curve for added design flexibility. An extension of our basic algorithm accommodates a generalized delay model which takes into account the effect of signal slew on buffer delay which can contribute substantially to overall delay. To the best of our knowledge, our approach represents the first work on buffer insertion to incorporate signal slew into the delay model while guaranteeing optimality. The effectiveness of these methods is demonstrated experimentally.
Renegade Asset Markets

Local markets with tight land use controls result in prices rising relative to wages and affordability. Affordability is eased by unconventional but risky finance. Tight land use and loose financing in these renegade markets concentrates the impact of national or international shocks. A positive demand shock raises prices in these tight markets. If ongoing price momentum is expected, households switch to ownership and landlords reduce the rental stock. House prices, rents and occupancy rise and fall together in these markets. A five-equation sequential structure in land use, financial contracts, house prices, rents and vacancy for 17 United States cities confirms geographical concentration. Coastal California and South Florida are fundamentally risky markets. Discount rates there are three percentage points higher than the sample median. Two percentage points are attributable to land use and the other to unconventional finance. National and international financial crises are highly concentrated regionally.
Improving First‐Year Engineering Education*

In September of 1998, the College of Engineering at the University of Massachusetts Dartmouth (UMD) piloted an innovative, integrated, first-year curriculum. It dramatically changed 31 credits across two semesters. The program was modeled after several previous successful undergraduate experiments at other universities such as those in the NSF Foundation Coalition and at Rensselaer Polytechnic Institute. The new program at UMD included This paper describes the new curriculum, some of the practical considerations in its design, and the way it has functioned. Significant improvements demonstrated after one year of operation include integrating the introductory sequences in physics, calculus, chemistry, English and engineering teaching and using teamwork among students and faculty using a specially designed technology oriented classroom using active and cooperative learning methods encouraging formation of a community of students by block-scheduling classes and grouping students in the dorms using rigorous assessment to evaluate performance. the attrition rate of first-year engineering students more than halved the percentage of students passing two semesters of physics on schedule nearly doubled the percentage of students passing calculus on schedule increased by 40% the performance of students on common final exams in both physics and calculus significantly increased.
Accurate derivative evaluation for any Grad-Shafranov solver

We present a numerical scheme that can be combined with any fixed boundary finite element based Poisson or Grad-Shafranov solver to compute the first and second partial derivatives of the solution to these equations with the same order of convergence as the solution itself. At the heart of our scheme is an efficient and accurate computation of the Dirichlet to Neumann map through the evaluation of a singular volume integral and the solution to a Fredholm integral equation of the second kind. Our numerical method is particularly useful for magnetic confinement fusion simulations, since it allows the evaluation of quantities such as the magnetic field, the parallel current density and the magnetic curvature with much higher accuracy than has been previously feasible on the affordable coarse grids that are usually implemented.
Dimensions, Issues, and Bills: Appropriations Voting on the House Floor

One of the fundamental findings in the congressional literature is that one or sometimes two dimensions can successfully describe roll-call voting. In this paper we investigate if we can reach the same conclusions about low dimensionality when we divide the roll-call agenda into subsets of relatively homogeneous subject matter. We are primarily interested in the degree to which the same ordering of representatives is yielded across these different groups of votes. To conduct our analysis we focus on all roll calls on the 13 annual appropriations bills across eight congresses. When we concentrate on these smaller issue areas, we find that voting is multidimensional and members do not vote in a consistent ideological fashion across all issue areas.
A Practical Differentially Private Random Decision Tree Classifier

In this paper, we study the problem of constructing private classifiers using decision trees, within the framework of differential privacy. We first present experimental evidence that creating a differentially private ID3 tree using differentially private low-level queries does not simultaneously provide good privacy and good accuracy, particularly for small datasets. In search of better privacy and accuracy, we then present a differentially private decision tree ensemble algorithm based on random decision trees. We demonstrate experimentally that this approach yields good prediction while maintaining good privacy, even for small datasets. We also present differentially private extensions of our algorithm to two settings: (1) new data is periodically appended to an existing database and (2) the database is horizontally or vertically partitioned between multiple users.
European Consumer Preferences for U.S. and Domestic Beef: Willingness to Pay for Source Verification, Hormone-Free, and Genetically Modified Organism-Free Beef

The European Union (EU) ban on the production and importation of meat derived from animals treated with growth-promoting hormones has spurred considerable debate. However, relatively little research has considered how EU consumers have been affected or how they feel about the ban. The purpose of this research is to determine beef product preferences of EU consumers and to elicit how much, if anything, these consumers are willing to pay for their preferred attributes. More specifically, this study uses a non-hypothetical choice experiment to evaluate how EU consumers value beef steaks from animals produced using growth hormones, fed genetically modified feeds, and from U.S. origin relative to their typical, domestically produced steaks. Results reveal that consumers in London, England; Frankfurt, Germany; and Paris, France are on average willing to pay a premium ($8.75/lb, $3.25/lb, and $0.98/lb, respectively) for a "USDA Choice No Hormones or GMOs" steak as opposed to their "Domestic Typical" steak. Additionally, these consumers indicated a willingness to pay a premium for both U.S. produced hormone-free beef ($0.86/lb in London, $1.93/lb in Frankfurt, and $0.30/lb in Paris) and for U.S. produced beef free of genetically modified organisms ($8.88/lb in London, $2.55/ lb in Frankfurt, and $2.79/lb in Paris) relative to USDA Choice beef.
Density perturbations in transonic sluing laser beams

A linearized theory is presented for density perturbations induced in a sluing laser beam as a function of time after beam turn-on and cross-flow Mach number M. The net local density perturbation is expressed as the sum of an isobaric and isentropic perturbation. A closed-form solution is obtained for M = 1, where the isentropic perturbations peak, and uniform heat addition in a circular beam. The results are compared with a corresponding one-dimensional beam. Poor agreement is found at large time, where the isentropic density perturbation varies as t and t1/2 for the one-dimensional and two-dimensional cases, respectively. An order-of-magnitude estimate for the final steady-state density perturbation, at M = 1, and the time scale in which it is achieved are obtained by consideration of nonlinear effects.
Aerodynamics of Ballistic Re-entry Vehicles with Asymmetric Nosetips

Two numerical techniques for the prediction of inviscid flowfields about re-entry vehicles with asymmetric nosetips are described and validated by comparison to ground test data. One technique is a finite-difference integration of the exact governing equations; the second method presented is an approximate technique suitable for application to statistical dispersion analyses, which retains many features of the more exact approach. The application of such flowfield techniques to the reconstruction of nosetip shapes from flight data is demonstrated.
Enhanced motion and sizing of bank in moving-bank MMAE

The focus of this research is to provide methods for generating precise parameter estimates in the face of potentially significant parameter variations such as system component failures. The standard multiple model adaptive estimation (MMAE) algorithm uses a bank of Kalman filters, each based on a different model of the system. Parameter discretization within the MMAE refers to selection of the parameter values assumed by the elemental Kalman filters, and dynamically redeclaring such discretization yields a moving-bank MMAE. A new online parameter discretization method is developed based on the probabilities associated with the generalized chi-squared random variables formed by residual information from the elemental Kalman filters within the MMAE. This new algorithm is validated through computer simulation of an aircraft navigation system subjected to interference/jamming while attempting a successful precision landing of the aircraft.
Green's-function method for crystal films and surfaces

The Green's-function method is adapted to the problem of an electron moving in a crystal film. The potential is taken as spherical in the atomic spheres and as dependent only on the coordinate normal to the film in the regions just outside the bounding atom planes. The appropriate new structure constants are defined. With the aid of the necessary logarithmic derivatives a rather small set of simultaneous linear equations is obtained from which eigenvalues and eigenfunctions can be calculated. In conjunction with the density functional formalism this procedure provides a convenient method for self-consistently calculating the electronic structure of films and surfaces. Comparison with earlier work by Pharisean, Scherer, Cooper, and Beeby is made.
p53 polymorphism, human papillomavirus infection in the oral cavity, and oral cancer.

Abstract Objectives: Human papillomavirus (HPV) infection has emerged as a risk factor in oral carcinogenesis. An arginine-coding polymorphism of the tumor suppressor protein p53 at codon 72 is more readily degraded by the HPV oncoprotein E6. Our objective was to evaluate the association between p53 polymorphism at codon 72 and HPV infection in the oral cavity, as well as its association with oral cancer. Study Design: Oral squamous cells from 202 patients with oral cancer and 333 age-sex frequency matched controls were evaluated by polymerase chain reaction for the presence and type of HPV and for alleles of codon 72 in p53. Fisher exact test and χ 2 tests were used to evaluate the data. Results: The p53 codon 72 polymorphism is not associated with HPV infection, whether comparing HPV-negative controls with HPV-positive controls or comparing HPV-negative cases with HPV-positive cases. Additionally, we found no association with the codon 72 polymorphism and oral cancer, whether comparing HPV-negative controls with HPV-negative cases or comparing HPV-positive controls with HPV-positive cases. Conclusions: There is no association between p53 codon 72 polymorphism and HPV infection or between the p53 polymorphism and the risk of oral cancer. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2000;90:334-9)
Housing Return and Construction Cycles

This paper presents a model that derives both housing returns and housing construction patterns from events in the real economy. The value of a home, unlike the value of many other financial assets, depends upon the care its owner exerts on upkeep. Within the model banks respond to this moral hazard problem by restricting the size of the loans they are willing to issue. As a result housing prices no longer follow a random walk, but rather are tied to changes in the endowment process which are both predictable and time varying. That is, in some states of nature homeowners expect to earn an above market return on their housing purchase while in others they expect to earn a below market return. Developers in the model are fully cognizant of the housing price process and react accordingly. The result is a construction cycle that seems at odds with conventional wisdom. When endowments are growing quickly (a city with a rapidly growing economy) housing prices exhibit above market expected returns. However, since housing prices are expected to increase faster than the rate of interest, developers delay construction. Thus, during periods of rapid expected economic growth housing construction ceases until one reaches the crest whereupon development booms. In response housing supplies dwindle during economic booms (as homes deteriorate) and then increase when the boom ends.
Should we regulate financial information

Regulations that require asset issuers to disclose payoff-relevant information to potential buyers sound like obvious measures to increase investor welfare. But in many cases, such regulations harm investors. In an equilibrium model, asset returns compensate investors for risk. By making payoffs less uncertain, disclosure reduces risk and therefore reduces return. As high-risk, high-return investments disappear, investor welfare falls. Of course, information is still valuable to each individual investor. But acquiring information is like a prisoners’ dilemma. Each investor is better off with the information, but collectively investors are better off if they remain uninformed. The only cases in which providing information improves investors’ welfare are ones where there would otherwise be severe asymmetric information. Using a model of information markets, the paper explores when such outcomes are likely to arise. When we extend the model so that financial markets with information allocate the real capital stock more efficiently, these conclusions do not change. Disclosure improves efficiency, but more efficient firms do not have more risk and therefore do not offer investors higher return. Instead, they simply command a higher price, which only benefits the asset issuer. Since the efficiency gains are fully internalized by asset issuers, who can choose to disclose without disclosure being mandatory, the efficiency argument is not a logical rationale for regulation.
How Economic Segregation Affects Children's Educational Attainment

Economic segregation increased in the U.S. between 1970 and 1990. Three hypotheses suggest that economic segregation affects low-income children's educational attainment, but they provide different predictions about the direction of the effect. I combine census data with data from the Panel Study of Income Dynamics to show that an increase in economic segregation between census tracts in the same state hardly changes overall educational attainment but it exacerbates inequality between high-income and low-income children. With overall inequality held constant changes in economic inequality within census tracts have little effect on low-income children's educational attainment. But changes in inequality between census tracts reduce the educational attainment of low-income children. Substituting segregation between school districts for segregation between census tracts yields the same conclusions.
Modeling and design of a monolithically integrated power converter on SiC

To fully explore the high temperature and high power density potential of the 4H-SiC material, not only power devices need to be fabricated on SiC, but also the circuitries for signal generation/processing, gate driver and control. In this paper, static and dynamic characteristics of SiC lateral JFET (LJFET) devices are numerically simulated and compact circuit models developed. Based on these models, analog and digital integrated circuits functional blocks such as OPAMP, gate driver and logic gates are then designed and simulated. Finally, a fully integrated power converter including pulse-width-modulation circuit, over-temperature protection circuit and a power boost converter is designed and simulated. The converter has an input of 200 V and an output voltage of 400 V, 2.5 A, operating at 1 kW and 5 MHz.
Quantifying stock-price response to demand fluctuations.

We empirically address the question of how stock prices respond to changes in demand. We quantify the relations between price change G over a time interval Deltat and two different measures of demand fluctuations: (a) Phi, defined as the difference between the number of buyer-initiated and seller-initiated trades, and (b) Omega, defined as the difference in number of shares traded in buyer- and seller-initiated trades. We find that the conditional expectation functions of price change for a given Phi or Omega, (Phi) and (Omega) ("market impact function"), display concave functional forms that seem universal for all stocks. For small Omega, we find a power-law behavior (Omega) approximately Omega(1/8) with delta depending on Deltat (delta approximately 3 for Deltat=5 min, delta approximately 3/2 for Deltat=15 min and delta approximately 1 for large Deltat). We find that large price fluctuations occur when demand is very small-a fact that is reminiscent of large fluctuations that occur at critical points in spin systems, where the divergent nature of the response function leads to large fluctuations.