cssi/SciSciGPT-SciSciNet huggingface dataset:
Effect of basal gastric acid secretion on the pharmacodynamics of ranitidine.

Twelve patients with inactive ulcer disease were administered placebo and ranitidine via bolus and continuous intravenous infusions, at doses ranging from 50 every 8 h, to 12.5 mg/h for 24 h. Gastric acid was collected for 20 min each h for 24 h, and ranitidine serum concentrations were measured ± every 2 h, during each of the six study periods. Cosinor analysis of gastric acid secretion during placebo treatment revealed a significant circadian rhythm in all subjects. Mesor acid output ranged from 1.7 to 11.6 mmol/h (mean 5.6 ± 2.8 mmol/h) and the amplitude ranged from 0.7 to 6.5 mmol/h (mean 2.8 ±1.6 mmol/h). Peak acid output (acrophase) occurred at 10 p.m. ± 3 h. A pharmacodynamic model, relating ranitidine serum concentration to hourly acid secretion, was derived, which incorporated the circadian change in basal acid output. Data for this fractional response model included basal acid secretion–as determined by time of day, measured acid secretion, and associated serum ranitidine concentration. The 50% ...
Patient Streaming as a Mechanism for Improving Responsiveness in Emergency Departments

Crisis-level overcrowding conditions in emergency departments EDs have led hospitals to seek out new patient-flow designs to improve both responsiveness and safety. One approach that has attracted attention and experimentation in the emergency medicine community is a system in which ED beds and care teams are segregated and patients are “streamed” based on predictions of whether they will be discharged or admitted to the hospital. In this paper, we use a combination of analytic and simulation models to determine whether such a streaming policy can improve ED performance, where it is most likely to be effective, and how it should be implemented for maximum performance. Our results suggest that the concept of streaming can indeed improve patient flow, but only in some situations. First, ED resources must be shared across streams rather than physically separated. This leads us to propose a new “virtual-streaming” patient flow design for EDs. Second, this type of streaming is most effective in EDs with 1 a high percentage of admitted patients, 2 longer care times for admitted patients than discharged patients, 3 a high day-to-day variation in the percentage of admitted patients, 4 long patient boarding times e.g., caused by hospital “bed-block”, and 5 high average physician utilization. Finally, to take full advantage of streaming, physicians assigned to admit patients should prioritize upstream new patients, whereas physicians assigned to discharge patients should prioritize downstream old patients.
Planet formation by coagulation: A focus on Uranus and Neptune

Planets form in the circumstellar disks of young stars. We review the basic physical processes by which solid bodies accrete each other and alter each others' random velocities, and we provide order-of-magnitude derivations for the rates of these processes. We discuss and exercise the two-groups approximation, a simple yet powerful technique for solving the evolution equations for protoplanet growth. We describe orderly, runaway, neutral, and oligarchic growth. We also delineate die conditions under which each occurs. We refute a popular misconception by showing that the outer planets formed quickly by accreting small bodies. Then we address the final stages of planet formation. Oligarchy ends when the surface density of the oligarchs becomes comparable to that of the small bodies. Dynamical friction is no longer able to balance viscous stirring and the oligarchs' random velocities increase. In the inner-planet system, oligarchs collide and coalesce. In the outer-planet system, some of the oligarchs are ejected. In both the inner- and outer-planet systems, this stage ends once the number of big bodies has been reduced to the point that their mutual interactions no longer produce large-scale chaos. Subsequently, dynamical friction by the residual small bodies circularizes and flattens their orbits. The final stage of planet formation involves the clean up of the residual small bodies. Clean up has been poorly explored.
Single Axis Piezoceramic Gimbal

This paper describes the fabrication, testing, and analysis of a single axis piezoceramic gimbal. The fabrication process consists of pre-stressing a piezoceramic wafer using a high-temperature thermoplastic polyimide and a metal foil. The differential thermal expansion between the ceramic and metal induces a curvature. The piezoceramic is mounted on a support mechanism and a mirror is attached to the piezoceramic. A finite element analysis of the gimbal is described and the predicted gimbal angle versus applied voltage is compared to experimental results.
Solutions to the XXX type Bethe ansatz equations and flag varieties

We consider a version of the AN Bethe equation of XXX type and introduce a reporduction procedure constructing new solutions of this equation from a given one. The set of all solutions obtained from a given one is called a population. We show that a population is isomorphic to the slN+1 flag variety and that the populations are in one-to-one correspondence with intersection points of suitable Schubert cycles in a Grassmanian variety. We also obtain similar results for the root systems BN and CN. Populations of BN and CN type are isomorphic to the flag varieties of CN and BN types respectively.
Ambulation: A Tool for Monitoring Mobility Patterns over Time Using Mobile Phones

An important tool for evaluating the health of patients who suffer from mobility-affecting chronic diseases such as MS, Parkinson’s, and Muscular Dystrophy is assessment of how much they walk. Ambulation is a mobility monitoring system that uses Android and Nokia N95 mobile phones to automatically detect the user’s mobility mode. The user’s only required interaction with the phone is turning it on and keeping it with him/her throughout the day, with the intention that it could be used as his/her everyday mobile phone for voice, data, and other applications, while Ambulation runs in the background. The phone uploads the collected mobility and location information to a server and a secure, intuitive web-based visualization of the data is available to the user and any family, friends or caregivers whom they authorize, allowing them to identify trends in their mobility and measure progress over time and in response to varying treatments.
Maintaining optimum light output with a thermally conductive heat pipe

Current research in the area of lamp wall temperature control for the purpose of enhancing light output under elevated temperatures is described. More specifically, a thermally conductive heat pipe has been employed to maintain optimum lamp wall temperature under varied ambient temperatures. The advantages of a heat pipe over previous methods of enhancing light output include its independence from power and flexibility in orientation within the fixture. The experiments described include the calibration of a heat pipe against a known thermal load, the application of a heat pipe to a lamp in a test chamber, and the placement of a heat pipe within a fixture. Theory and experimental data indicate that optimum lamp operating conditions can be maintained throughout an ambient temperature range that typically reduces light output by 20%. >
Can Mentoring Help Female Assistant Professors? Interim Results from a Randomized Trial

While much has been written about the potential benefits of mentoring in academia, very little research documents its effectiveness. We present data from a randomized controlled trial of a mentoring program for female economists organized by the Committee for the Status of Women in the Economics Profession and sponsored by the National Science Foundation and the American Economics Association. To our knowledge, this is the first randomized trial of a mentoring program in academia. We evaluate the performance of three cohorts of participants and randomly-assigned controls from 2004, 2006, and 2008. This paper presents an interim assessment of the program’s effects. Our results suggest that mentoring works. After five years the 2004 treatment group averaged .4 more NSF or NIH grants and 3 additional publications, and were 25 percentage points more likely to have a top-tier publication. There are significant but smaller effects at three years post-treatment for the 2004 and 2006 cohorts combined. While it is too early to assess the ultimate effects of mentoring on the academic careers of program participants, the results suggest that this type of mentoring may be one way to help women advance in the Economics profession and, by extension, in other male-dominated academic fields.
Growth equation with a conservation law.

We investigate an interface growth equation with a conservation law. The interaction is characterized by an integral kernel. The equation contains the Kardar-Parisi-Zhang, Sun-Guo-Grant, and Molecular-Beam Epitaxy growth equations as special cases and allows for a unified investigation of growth equations. We perform a dynamic renormalization-group analysis and determine the scaling behavior and universality classes for such growth models with a conservation law.
Bringing entrepreneurial ideas to life

Prior work on the commercialization of innovation is motivated by competitive dynamics between startup and incumbent firms and has looked at the determinants of innovator commercialization mode. We contribute to the literature by examining variation in performance resulting from the choice of whether to innovate technologically in new ventures. The institutional and business environment conditions which strategies lead to higher performance for start-up innovators. In contrast to the factors shown to determine commercialization mode, we show that the team characteristics and economic environment play a stronger role in predicting an innovator's entrepreneurial firm performance. Using unique data from a novel survey of entrepreneurial firms founded over five decades and across diverse industries, we show the conditions when technology focused vs. functionally diverse founding teams outperform. In addition, we show that in certain environments firms with more highly original innovations and innovating firms founded during a recession have higher performance.
PQCD ANALYSIS OF PARTON-HADRON DUALITY

We propose an extraction of the running coupling constant of QCD in the infrared region from experimental data on deep inelastic inclusive scattering at Bjorken x → 1. We first attempt a perturbative fit of the data that extends NLO PQCD evolution to large x values and final state invariant mass, W, in the resonance region. We include both target mass corrections and large x resummation effects. These effects are of order $\mathcal{O}(1/Q^2)$, and they improve the agreement with the Q2 dependence of the data. Standard analyses require the presence of additional power corrections, or dynamical higher twists, to achieve a fully quantitative fit. Our analysis, however, is regulated by the value of the strong coupling in the infrared region that enters through large x resummation effects, and that can suppress, or absorb, higher twist effects. Large x data therefore indirectly provide a measurement of this quantity that can be compared to extractions from other observables.
Spacetime Geometry in Higher Spin Gravity

Higher spin gravity is an interesting toy model of stringy geometry. Particularly intriguing is the presence of higher spin gauge transformations that redefine notions of invariance in gravity: the existence of event horizons and singularities in the metric become gauge dependent. In previous work, solutions of spin-3 gravity in the SL(3,R) × SL(3,R) Chern-Simons formulation were found, and were proposed to play the role of black holes. However, in the gauge employed there, the spacetime metric describes a traversable wormhole connecting two asymptotic regions, rather than a black hole. In this paper, we show explicitly that under a higher spin gauge transformation these solutions can be transformed to describe black holes with manifestly smooth event horizons, thereby changing the spacetime causal structure. A related aspect is that the Chern-Simons theory admits two distinct AdS3 vacua with different asymptotic W-algebra symmetries and central charges. We show that these vacua are connected by an explicit, Lorentz symmetry-breaking RG flow, of which our solutions represent finite temperature generalizations. These features will be present in any SL(N,R) × SL(N,R) Chern-Simons theory of higher spins.
METAL-POOR FIELD BLUE STRAGGLERS: MORE EVIDENCE FOR MASS TRANSFER

We report radial velocity studies of five candidate metal-poor field blue stragglers, all known to be deficient in lithium. Four of the five stars are single-lined spectroscopic binaries, with periods ranging from 302 to 840 days, and low orbital eccentricities, in agreement with similar behavior found for other blue straggler candidates by Preston & Sneden and Carney et al. The limited data available for lithium abundances indicate that all blue straggler binaries have depleted lithium, but that constant velocity stars generally have normal lithium abundances. This suggests that the "lithium gap" for hot metal-poor main-sequence stars may not exist or lies at higher temperatures than found in the Hyades. Our results and those of Preston & Sneden show higher values of vrot sin i for the binary stars than those of comparable temperature constant velocity stars. The orbital periods are too long for tidal effects to be important, implying that spin-up during mass transfer when the orbital separations and periods were smaller is the cause of the enhanced rotation. The mass function distribution is steeper for the blue straggler binary stars than that of lower mass single-lined spectroscopic binaries, indicating a narrower range in secondary masses. We argue that if all secondaries are white dwarfs with the same mass, it is probably around 0.55 M⊙. The models of Rappaport et al., applied to white dwarf secondaries, suggest that the orbital elements of all metal-poor binary blue stragglers are consistent with stable mass transfer, with the possible exception of G202-65.
Spitzer Observations of Two TW Hydrae Association Brown Dwarfs

We present Spitzer Space Telescope observations of two TW Hydrae Association brown dwarfs, 2MASSW J1207334-393254 and 2MASSW J1139511-315921, in the IRAC and MIPS 24 µm bands. Based on their IRAC colors, we have classified them as Classical and Weak line T Tauri stars, respectively. For 2MASSW J1207334-393254, we have found that a flat disk model fits the data very well. This brown dwarf shows the presence of warm (T & 100 K) circumstellar dust close (R . 0.2 AU) to it, and does not display any signs of cleansing of dust within several AU of the star. In comparison with other TWA members that show excess in IR, we suggest that there exists a different disk evolution/dust processing mechanism for stellar and sub-stellar objects. 2MASSW J1139511315921 does not show any significant excess in any of the IRAC bands, but a small one at 24 µm, which is not significant enough to suggest the presence of warm dust around this star. It shows signs of dust cleansing in the inner several AU, similar to most of the other TWA members.
Influence of the El Niño‐La Niña cycle on satellite‐derived primary production in the California Current

[1] Time series of phytoplankton net primary production (NPP) for the California Current were derived using satellite data and the VGPM primary productivity model for a 5-year period (1997–2001) including the 1997–98 El Nino. NPP had a strong annual periodicity correlated with the El Nino-La Nina cycle. The most obvious effects of the El Nino on NPP were 100-300 km off the coast: a reduction by 30% off Southern California but an increase by 40% off Baja California. During its peak El Nino decreased NPP by 10–15% (1.5 Tg C month−1) in the 1000-km band off Southern California but increased by 20–30% off Northern and Southern Baja (4 Tg C month−1). The total annual NPP was lowest during the El Nino years of 1997–1998 and peaked in 2000. Trends of increasing NPP and zooplankton volume were observed off Central and Southern California.
Remanence and longitudinal recording properties of advanced particulate media and metal thin-film media

A comparison is made of the magnetic remanence and longitudinal recording properties of advanced particulate media with metal thin-film media. The remanence properties were studied parallel and orthogonal to the track direction and were diagnostic of recording performance. The recording properties were measured using thin-film heads with inductive-write and magnetoresistive-read elements. Longitudinal barium ferrite and isotropic cobalt alloy media show substantially narrower switching field distributions (SFDs) compared to acicular cobalt-modified gamma -Fe/sub 2/O/sub 3/ media. Narrow SFD, high H/sub c/, and small M/sub r/ delta lead to small, well-defined magnetic transitions and high bit densities. Indeed, there is a linear correlation between the calculated transition length, a, and the linear density. Results confirm that particulate barium ferrite and cobalt alloy media have very small transition lengths and high linear densities. Cobalt-modified gamma -Fe/sub 2/O/sub 3/ media show lower linear densities; however, their intrinsic signal-to-noise ratios (SNR) are much higher compared to the barium ferrite and cobalt alloy media. The trend of noise with increasing density or frequency differs for the three types of media. >
Salvage bevacizumab (rhuMAB VEGF)-based therapy after multiple prior cytotoxic regimens in advanced refractory epithelial ovarian cancer.

Abstract Objectives. Bevacizumab (BEV) is a humanized monoclonal antibody against vascular endothelial growth factor. We reviewed our experience with BEV in patients with recurrent advanced epithelial ovarian cancer who had failed multiple prior chemotherapeutic regimens. Methods. Thirty-two patients not participating in an ongoing clinical trial were treated with BEV (15 mg/kg every 3 weeks IV). Demographic and clinicopathologic data, clinical outcomes, and adverse events were extracted from patient charts. RECIST and CA-125 Rustin criteria were retrospectively applied to evaluate response and progression. Median progression-free survival (PFS) and overall survival (OS) were determined using Kaplan–Meier methods. Adverse events were retrospectively categorized using the common terminology criteria for adverse events version 3. Results. The median patient age was 57 years (range 35–80) with 84% being Caucasian and 50% having a GOG performance status of 2. FIGO stages included 80% stage III and 10% stage IV. The tumors were mostly grades 2 (29%) and 3 (64%) and serous histological subtype (69%). All patients had failed multiple prior cytotoxic chemotherapies (median of 5 (range 2–10)) prior to BEV. The median duration of follow-up was 4.8 months (range 0.4–16.3). Twenty-three patients were treated with BEV alone, 2 received BEV with another chemotherapy regimen (5-FU/lecovorin plus oxaliplatin, cyclophosphamide), and 8 initially received BEV alone, followed by BEV with capcitabine, cyclophosphamide, docetaxel, carboplatin, or weekly paclitaxel. A median of 6 cycles (range 1–20) with 196 total doses of BEV was administered. One patient was lost to follow-up after cycle 1. We observed a 16% response rate (all in those treated with BEV alone) with 62.5% of patients demonstrating stable disease. Median OS was 6.9 months, and the median PFS was 5.5 months. Three grade 3 and no grade 4 adverse events were observed. Grade 3 toxicities included hypertension, proteinuria, and enterocutaneous fistula. The fistula occurred after 5 cycles of BEV in a patient who had undergone 7 debulking surgeries prior to BEV. Conclusions. BEV is generally well tolerated after multiple prior cytotoxic regimens and results in significant clinical benefit among women with recurrent ovarian cancer.
PDF optimized parametric vector quantization of speech line spectral frequencies

A computationally efficient, high quality, vector quantization scheme based on a parametric probability density function (PDF) is proposed. In this scheme, the observations are modeled as i.i.d realizations of a multivariate Gaussian mixture density. The mixture model parameters are efficiently estimated using the expectation maximization (EM) algorithm. A low complexity quantization scheme using transform coding and bit allocation techniques which allows for easy mapping from observation to quantized value is developed for both fixed rate and variable rate systems. An attractive feature of this method is that source encoding using the resultant codebook involves very few searches and its computational complexity is minimal and independent of the rate of the system. Furthermore, the proposed scheme is bit scalable and can switch seamlessly between a memoryless quantizer and a quantizer with memory. The usefulness of the approach is demonstrated for speech coding where Gaussian mixture models are used to model speech line spectral frequencies. The performance of the memoryless quantizer is 1-3 bits better than conventional quantization schemes.
Large Terrain Modeling and Visualization for Planets

Physics-based simulations are actively used in the design, testing, and operations phases of surface and near-surface planetary space missions. One of the challenges in real-time simulations is the ability to handle large multi-resolution terrain data sets within models as well as for visualization. In this paper, we describe special techniques that we have developed for visualization, paging, and data storage for dealing with these large data sets. The visualization technique uses a real-time GPU-based continuous level-of-detail technique that delivers multiple frames a second performance even for planetary scale terrain model sizes.
PANEL COINTEGRATION: ASYMPTOTIC AND FINITE SAMPLE PROPERTIES OF POOLED TIME SERIES TESTS WITH AN APPLICATION TO THE PPP HYPOTHESIS

We examine properties of residual-based tests for the null of no cointegration for dynamic panels in which both the short-run dynamics and the long-run slope coefficients are permitted to be heterogeneous across individual members of the panel. The tests also allow for individual heterogeneous fixed effects and trend terms, and we consider both pooled within dimension tests and group mean between dimension tests. We derive limiting distributions for these and show that they are normal and free of nuisance parameters. We also provide Monte Carlo evidence to demonstrate their small sample size and power performance, and we illustrate their use in testing purchasing power parity for the post–Bretton Woods period.I thank Rich Clarida, Bob Cumby, Mahmoud El-Gamal, Heejoon Kang, Chiwha Kao, Andy Levin, Klaus Neusser, Masao Ogaki, David Papell, Pierre Perron, Abdel Senhadji, Jean-Pierre Urbain, Alan Taylor, and three anonymous referees for helpful comments on various earlier versions of this paper. The paper has also benefited from presentations at the 1994 North American Econometric Society Summer Meetings in Quebec City, the 1994 European Econometric Society Summer Meetings in Maastricht, and workshop seminars at the Board of Governors of the Federal Reserve, INSEE-CREST Paris, IUPUI, Ohio State, Purdue, Queens University Belfast, Rice University–University of Houston, and Southern Methodist University. Finally, I thank the following students who provided assistance in the earlier stages of the project: Younghan Kim, Rasmus Ruffer, and Lining Wan.
‘Locking’ dendrimer conformation through metal coordination

Abstract Chiral intramolecularly hydrogen-bonded dendrons that fold into a dynamically biased helical conformation can be ‘locked’ in kinetically controlled conformations by coordination to copper(II) metal centers. Covalent bonding of each pyridine-2,6-dicarboxamide repeat unit of the dendrons to a copper metal center forces this subunit to exist in only the syn – syn conformation and dramatically rigidifies the dendron structure.
Self-Employment in the Developing World

Summary This paper analyzes heterogeneity among the self-employed in 74 developing countries, representing two-thirds of the population of the developing world. After profiling how worker characteristics vary by employment status, it classifies self-employed workers outside agriculture as “successful” or “unsuccessful” entrepreneurs, based on two measures of success: whether the worker is an employer, and whether the worker resides in a non-poor household. Four main findings emerge. First, jobs exhibit a clear pecking order, with household income and worker education highest for employers, followed by wage and salaried employees, non-agricultural own-account workers, non-agricultural unpaid family workers, and finally agricultural workers. Second, a substantial minority of own-account workers reside in non-poor households, suggesting that their profits are often a secondary source of household income. Third, as per capita income increases across countries, the structure of employment shifts rapidly, first out of agriculture into unsuccessful non-agricultural self-employment, and then mainly into non-agricultural wage employment. Finally, roughly one-third of the unsuccessful entrepreneurs share similar characteristics with their successful counterparts, suggesting they have the potential to be successful but face constraints to growth. The authors conclude that although interventions such as access to credit can benefit a substantial portion of the self-employed, effectively targeting the minority of self-employed with higher growth potential is important, particularly in low-income contexts. The results also highlight the potential benefits of policies that facilitate shifts in the nature of work, first from agricultural labor into non-agricultural self-employment, and then into wage and salaried jobs.
On Black Intelligence.

If a tree is to be judged by its fruit, if the intelligence of a race bears any relation to its accomplishment, it seems difficult to draw any conclusion other than that the Black and Brown races are inferior to the white race [R. S. Ellis, 1928: 284].
A Theory of the Firm with Non‐binding Employment Contracts

This paper examines an employment relation in which individual workers enjoy some bargaining power vis-a-vis the firm although they are not unionized. The main elements of the situations studied here are that the employment contracts are non-binding across periods of production and that the firm has opportunities to replace workers. The paper analyzes a dynamic model in which the processes of contracting and recontracting between the firm and its workers are intertwined with the dynamic evolution of the firm's workforce. The analysis of the model is somewhat complicated because the employment level is a nondegenerate state variable that evolves over time and is affected by past decisions. The main analytical results characterize certain important equilibria: the profit maximizing and stationa˙ry equilibria. The unique stationary equilibrium is markedly inefficient: it exhibits inefficient over-employment and the steady state wages coincide with the workers' reservation wage. It confirms earlier results derived by Stole and Zwiebel (1996a,b) in the context of a static model and shows that they are very robust even when the firm has nearly frictionless hiring opportunities. In contrast, in the profit maximizing equilibrium the outcome is nearly efficient and the wage exhibits a mark-up over the reservation wage.
Paths and stability number in digraphs

The Gallai-Milgram theorem says that the vertex set of any digraph with stability number $k$ can be partitioned into $k$ directed paths. In 1990, Hahn and Jackson conjectured that this theorem is best possible in the following strong sense. For each positive integer $k$, there is a digraph $D$ with stability number $k$ such that deleting the vertices of any $k-1$ directed paths in $D$ leaves a digraph with stability number $k$. In this note, we prove this conjecture.
Confidence intervals and hypothesis testing for high-dimensional regression

Fitting high-dimensional statistical models often requires the use of non-linear parameter estimation procedures. As a consequence, it is generally impossible to obtain an exact characterization of the probability distribution of the parameter estimates. This in turn implies that it is extremely challenging to quantify the uncertainty associated with a certain parameter estimate. Concretely, no commonly accepted procedure exists for computing classical measures of uncertainty and statistical significance as confidence intervals or p- values for these models. We consider here high-dimensional linear regression problem, and propose an efficient algorithm for constructing confidence intervals and p-values. The resulting confidence intervals have nearly optimal size. When testing for the null hypothesis that a certain parameter is vanishing, our method has nearly optimal power. Our approach is based on constructing a 'de-biased' version of regularized M-estimators. The new construction improves over recent work in the field in that it does not assume a special structure on the design matrix. We test our method on synthetic data and a high-throughput genomic data set about riboflavin production rate, made publicly available by Buhlmann et al. (2014).
Diversity analysis of single and multiple beamforming

In this letter, we study two techniques, known as single and multiple beamforming, to exploit the perfect channel state information (CSI) available both at the transmitter and the receiver of a multiantenna wireless system. Assuming N and M are the number of antennas at the transmitter and the receiver, respectively, we show that single beamforming (transmission of a single symbol from all transmit antennas at the same time, employing the best subchannel) can achieve the maximum spatial diversity order in the channel (NM). We extend our analytical results to multiple beamforming (transmission of S symbols simultaneously, S>1) and calculate that the diversity order achievable for this system is (N-S+1)(M-S+1)
Tracking or rejecting rotational-angle dependent signals using time varying repetitive control

Rotational-angle is a natural clock for the internal combustion engine. Many of the engine control problems involve controlling actuators or mechanisms to track or reject signals that are periodic in the rotational-angle domain. However a periodic signal in the rotational-angle domain becomes cyclic but aperiodic in the time domain as the rotational speed changes. This phenomenon poses a great challenge for achieving asymptotic tracking or disturbance rejection. To take advantage of the fact that the signal is periodic in the rotational-angle domain, we can transform the actuator dynamics into the rotational-angle domain and design the controller correspondingly. However the linear time invariant (LTI) actuator model becomes linear time varying (LTV) after the transformation. Time varying repetitive control is then proposed to drive the time varying plant to track or reject periodic signals. The periodic signal internal model is embedded in the time varying feedback loop to ensure asymptotic performance. Simulation results demonstrate the effectiveness of the proposed algorithms.
In-Situ MOS Gate Engineering in a Novel Rapid Thermal/Plasma Multiprocessing Reactor

Low temperatures and short times are essential requirements of future VLSI processing and the use of plasma in conjunction with single-wafer lamp heating is a major step to realize this goal, In-situ multiprocessing reduces contamination and enhances yield. Reproducible growth of thin oxides in hot-wall furnaces is difficult due to long transient times and constant furnace temperatures. Since furnaces are not designed for single-wafer processing, no extensive in-situ real-time measurements can be performed. RTP of Si in O2 and NH3 ambients is an attractive technique for the growth of silicon nitride, silicon dioxide, nitrided oxides, oxidized nitrides, and application-specific insulators [1). We have also demonstrated the feasibility of low-temperature nitridation of Si in nitrogen plasma generated by microwave discharge [2]. LPCVD of tungsten (W) has emerged as a viable technology for VLSI. The convent ionalliot-wall furnaces are not suitable for reproducible high-rate W deposition and nonselective formation of W on insulators.
Management Accounting Education at the Millennium

This article examines the “journey” of management accounting education over the past 50 years, evaluates the state of the field today, and presents my personal observations about teaching approaches. I observe that we have seen a substantial addition of management accounting courses to business school curricula, and changes in what was conventionally known as “cost accounting” courses, over the past 50 years. In recent years, innovative topics have come primarily from practice and from empirical research about practice. The introduction of these innovations into courses, and the expansion of management accounting in business school curricula, has resulted in a field that is alive and well in academia. The future demand for management accounting courses may be in some jeopardy, however, because students might not see good job opportunities in management accounting. Management accounting educators must address these problems to avoid enrollment declines in management accounting. The way we teach management ...
Probing Unification with Chandra HETGS and XMM-Newton EPIC and RGS Spectroscopy of the Narrow Emission Line Galaxy NGC 2110

We present results from Chandra HETGS (250 ks over two epochs) and XMM-Newton EPIC and RGS (60 ks) observations of NGC 2110, which has been historically classified as a narrow emission line galaxy. Our results support the interpretation that the source is a Seyfert 2 viewed through a patchy absorber. The nuclear X-ray spectrum of the source is best described by a power law of photon index Γ ~ 1.7, modified by absorption from multiple layers of neutral material at a large distance from the central supermassive black hole. We report the strong detections of Fe Kα and Si Kα lines, which are marginally resolved with the Chandra HETGS, and we constrain the emission radius of the fluorescing material to 1 pc. There is some evidence for modest additional broadening at the base of the narrow Fe Kα core with a velocity ~4500 km s−1. We find tentative evidence for ionized emission (O VIII Lyα, an O VIII RRC feature, and possibly a Ne IX forbidden line) in the Chandra MEG and XMM-Newton RGS spectra, which could be associated with the known extended X-ray emission that lies ~160 pc from the nucleus. We suggest that the 1023 cm−2 partially covering absorber originates in broad-line region clouds in the vicinity of the AGN, and that the 3 × 1022 cm−2 coverer is likely to have a more distant origin and have a flattened geometry in order to allow the small-scale radio jet to escape.
Orbiter entry leeside heat-transfer data analysis

Heat-transfer data measured along the Space Shuttle Orbiter's leeward centerline and over the wing leeside surface during the STS-2 and STS-3 mission entries are presented. The flight data are compared with available wind-tunnel results. Flight heating levels are, in general, lower than those which are inferred from the wind tunnel results. This result is apparently due to the flight leeside flowfield remaining laminar over a larger Reynolds number range than that of corresponding ground test results. The flight/wind tunnel data comparisons confirm the adequacy of, and conservatism embodied in, the direct application of wind tunnel data at flight conditions for the design of Orbiter leeside thermal protection.
Aggregate Demand, Idle Time, and Unemployment*

This paper develops a model of unemployment fluctuations. The model keeps the architecture of the Barro and Grossman [1971] general disequilibrium model but replaces the disequilibrium framework on the labor and product markets by a matching framework. On the product and labor markets, both price and tightness adjust to equalize supply and demand. There is one more variable than equilibrium condition on each market, so we consider various price mechanisms to close the model, from completely flexible to completely rigid. With some price rigidity, aggregate demand influences unemployment through a simple mechanism: higher aggregate demand raises the probability that firms find customers, which reduces idle time for firms’ employees and thus increases labor demand, which in turn reduces unemployment. We use the comparative-statics predictions of the model together with empirical measures of quantities and tightnesses to re-examine the origins of labor market fluctuations. We conclude that (1) price and real wage are not fully flexible because product and labor market tightness fluctuate significantly; (2) fluctuations are mostly caused by labor demand and not labor supply shocks because employment is positively correlated with labor market tightness; and (3) labor demand shocks mostly reflect aggregate demand and not technology shocks because output is positively correlated with product market tightness.
A framework for dynamic energy efficiency and temperature management

While technology is delivering increasingly sophisticated and powerful chip designs, it is also imposing alarmingly high energy requirements on the chips. One way to address this problem is to manage the energy dynamically. Unfortunately, current dynamic schemes for energy management are relatively limited. In addition, they manage energy either for energy efficiency or for temperature control, but not for both simultaneously. In this paper, we design and evaluate for the first time an energy-management framework that tackles both energy efficiency and temperature control in a unified manner. We call this general approach Dynamic Energy Efficiency and Temperature Management (DEETM). Our framework combines many energy-management techniques and can activate them individually or in groups in a fine-grained manner according to a given policy. The goal of the framework is two-fold: maximize energy savings without extending application execution time beyond a given tolerable limit, and guarantee that the temperature remains below a given limit while minimizing any resulting slowdown. The framework successfully meets these goals. For example, it delivers a 40% energy reduction with only a 10% application slowdown.
Ligand design in gold catalysis and chemistry of gold-oxonium intermediates.

Gold catalysis is considered one of the most important breakthroughs in organic synthesis during the last decade. Many gold-catalyzed reactions suffer from high catalyst loading, which is a serious limitation on the application of gold catalysis in larger scale synthesis. Because ligands play a major role in the tuning of reactivity of transition metal catalysts, there has been an increased effort on rationally understanding ligand effects in gold catalysis and using a rational ligand design to achieve higher efficiency. In the first part of this chapter, selected examples of ligand design in gold catalysis are discussed. In the second part, the chemistry of gold–oxonium intermediate is examined. An oxonium intermediate is generated when a oxygen nucleophile (ketone, aldehyde, or ether) attacks a cationic gold-activated multiple bond. This oxonium intermediate, being a highly energetic species, has the potential to undergo further transformations such as electron transfer/rearrangement/protodeauration to form diverse products.
Inattentional blindness reflects limitations on perception, not memory: Evidence from repeated failures of awareness

Perhaps the most striking phenomenon of visual awareness is inattentional blindness (IB), in which a surprisingly salient event right in front of you may go completely unseen when unattended. Does IB reflect a failure of perception, or only of subsequent memory? Previous work has been unable to answer this question, due to a seemingly intractable dilemma: ruling out memory requires immediate perceptual reports, but soliciting such reports fuels an expectation that eliminates IB. Here we introduce a way of evoking repeated IB in the same subjects and the same session: we show that observers fail to report seeing salient events’ not only when they have no expectation, but also when they have the wrong expectations about the events nature. This occurs when observers must immediately report seeing anything unexpected, even mid-event. Repeated IB thus demonstrates that IB is aptly named: it reflects a genuine deficit in moment-by-moment conscious perception, rather than a form of inattentional amnesia.
Environmental dependence of dark matter halo growth – I. Halo merger rates

In an earlier paper, we quantified the mean merger rate of dark matter haloes as a function of redshift z, descendant halo mass M 0 , and progenitor halo mass ratio ξ using the Millennium simulation of the A cold dark matter cosmology. Here, we broaden that study and investigate the dependence of the merger rate of haloes on their surrounding environment. A number of local mass overdensity variables, both including and excluding the halo mass itself, are tested as measures of a halo's environment. The simple functional dependence on z, M 0 , and ξ of the merger rate found in our earlier work, is largely preserved in different environments, but we find that the overall amplitude of the merger rate has a strong positive correlation with the environmental densities. For galaxy-mass haloes, we find mergers to occur ∼2.5 times more frequently in the densest regions than in voids at both z = 0 and higher redshifts. Higher mass haloes show similar trends. We present a fitting form for this environmental dependence that is a function of both mass and local density and valid out to z = 2. The amplitude of the progenitor (or conditional) mass function shows a similar correlation with local overdensity, suggesting that the extended Press-Schechter model for halo growth needs to be modified to incorporate environmental effects.
Quantification of three-dimensional orthodontic force systems of T-loop archwires.

Abstract Objective: To demonstrate the three-dimensional (3D) orthodontic force systems of three commercial closing T-loop archwires using a new method and to quantify the force systems of the T-lo...
Redox control of N:P ratios in aquatic ecosystems.

The ratio of dissolved fixed inorganic nitrogen to soluble inorganic phosphate (N:P) in the ocean interior is relatively constant, averaging ~16 : 1 by atoms. In contrast, the ratio of these two elements spans more than six orders of magnitude in lakes and other aquatic environments. To understand the factors influencing N:P ratios in aquatic environments, we analyzed 111 observational datasets derived from 35 water bodies, ranging from small lakes to ocean basins. Our results reveal that N:P ratios are highly correlated with the concentration of dissolved O 2 below ~100 μ mol L ‐1 . At higher concentrations of O 2 , N:P ratios are highly variable and not correlated with O 2 ; however, the coefficient of variation in N:P ratios is strongly related to the size of the water body. Hence, classical Redfield ratios observed in the ocean are anomalous; this specific elemental stoichiometry emerges not only as a consequence of the elemental ratio of the sinking flux of organic matter, but also as a result of the size of the basins and their ventilation. We propose that the link between N:P ratios, basin size and oxygen levels, along with the previously determined relationship between sedimentary δ 15 N and oxygen, can be used to infer historical N:P ratios for any water body.
Bandit problems with side observations

An extension of the traditional two-armed bandit problem is considered, in which the decision maker has access to some side information before deciding which arm to pull. At each time t, before making a selection, the decision maker is able to observe a random variable X/sub t/ that provides some information on the rewards to be obtained. The focus is on finding uniformly good rules (that minimize the growth rate of the inferior sampling time) and on quantifying how much the additional information helps. Various settings are considered and for each setting, lower bounds on the achievable inferior sampling time are developed and asymptotically optimal adaptive schemes achieving these lower bounds are constructed.
Cyberterrorism: Postmodern State of Chaos

ABSTRACT This paper examines cyberterrorism and its potential to create a postmodern state of chaos. In general, chaos refers to a state of extreme confusion and disorder. This analysis breaks new ground in that it describes chaos theory as a foundation for better understanding cyberterrorism and explains how chaos theory and game theory are tightly coupled. The author also contrasts modern, conventional terrorism with postmodern, innovative cyberterrorism. The main idea is that the postmodern state of chaos caused by cyberterrorist attacks differs dramatically from the destruction caused by conventional terrorist acts. This comparison serves as the basis for making the point that cyberterrorism is not three-dimensional, it is not analog (but it is digital), and it exposes actors of cyberspace to new concepts of time and space. Another important argument is that the postmodern state of chaos implies the danger of cascading failures brought forth by cyberterrorists. A cascading failure is a succession of f...
Is the Social Security Crisis Really as Bad as We Think

Because they ignore the household-level and macroeconomic adjustments associated with longevity improvements, the actuarial projections of the Social Security Administration overestimate the Social Security crisis. Using a general-equilibrium model with heterogeneous agents and incomplete markets, I show that accounting for these adjustments, a significantly smaller decline in benefits is needed to balance the Social Security budget. Households respond to the longevity improvements by delaying retirement and Social Security benefit collection, working more hours, and by also saving more. In general equilibrium, these effects lead to a natural expansion of Social Security's tax base and generate significant delayed retirement credits, which the actuarial estimates completely overlook.
Catalyzing Corporate Commitment to Combating Corruption

This article considers what policy reforms may help catalyze corporate commitment to combating corruption. The starting point for this discussion is a voluntary, corporate principles approach to self-regulation. Such an approach should seek to encourage corporations to implement effective compliance and ethics programs and to disclose information related to their anti-corruption activities to relevant stakeholders. Although a corporate principles approach is a private initiative, there is a significant role for the public sector. This article discusses some of the ways that the public sector can support and further the goals of a corporate principles approach to combating corruption. The reforms discussed in this article include amnesty programs for corporations that self-disclose corrupt payments, the use of corporate monitors in the enforcement of anti-corruption laws, expanding the definition of corruption in criminal laws, sustainability reporting indicators related to bribery, and the implementation of multi-stakeholder initiatives to support a corporate principles approach.
Hybrid Periodic Boundary Condition for Particle Swarm Optimization

A molecular dynamics (MD) formulation of particle swarm optimization (PSO) is established formally. Based on this analogy, the periodic boundary condition (PBC) is introduced to the PSO method by postulating that the swarm environment is similar to crystal bulk materials studied using MD. A combination of soft and hard boundary modes is employed in the formulation of the hybrid version of the proposed PBC. The hybrid version represents a substantial modification of the scenario assumed in theoretical physics but is allowed here to suit the PSO environment. The hybrid PBC proved to be superior to previously established boundary conditions when applied to standard test functions and the practical problem of linear antenna array synthesis.