Scale Constraints Research Articles

Minimization of L/sub 2/-sensitivity for state-space digital filters subject to L/sub 2/-dynamic-range scaling constraints

The problem of minimizing an L/sub 2/-sensitivity measure subject to L/sub 2/-norm dynamic-range scaling constraints for state-space digital filters is formulated. It is shown that the problem can be converted into an unconstrained optimization problem by using linear-algebraic techniques. Next, the unconstrained optimization problem is solved by applying an efficient quasi-Newton algorithm with closed-form formula for gradient evaluation. The coordinate transformation matrix obtained is then used to construct the optimal state-space filter structure that minimizes the L/sub 2/-sensitivity measure subject to the scaling constraints. A numerical example is presented to illustrate the utility of the proposed technique.

PLS regression: A directional signal-to-noise ratio approach

We present a new approach to univariate partial least squares regression (PLSR) based on directional signal-to-noise ratios (SNRs). We show how PLSR, unlike principal components regression, takes into account the actual value and not only the variance of the ordinary least squares (OLS) estimator. We find an orthogonal sequence of directions associated with decreasing SNR. Then, we state partial least squares estimators as least squares estimators constrained to be null on the last directions. We also give another procedure that shows how PLSR rebuilds the OLS estimator iteratively by seeking at each step the direction with the largest difference of signals over the noise. The latter approach does not involve any arbitrary scale or orthogonality constraints.

Probing R-parity Violating Interactions via pp̄ → eμ + XChannel on Tevatron**The project supported by National Natural ScienceFoundation of China and the Special Fund of the Chinese Academy of Sciences

We investigate the lepton flavor violation processes pp̄→ eμ+X induced by R-parity violating interactions at theTevatron hadron collider. The theoretical calculation and MonteCarlo simulation demonstrate that with a set of suitable cuts onexperimental observables, one might be capable to reduce thestandard model physical background to a controllable level so thatthe signals of R-parity violating interactions could be detecteddistinctively. Furthermore, clear sneutrino information can be abstracted from the purified event sample where other SUSY scalarquark ``pollution'' is heavily suppressed. We conclude that with areasonable assumption of 10 fb-1 integrated luminosity, theexperiments at the Tevatron machine would have potential todiscover sneutrino in the region of mν̃ ≤ 400 GeV vialepton flavor violation eμ production channels, or extend themass scale constraint up to mν̃ ≥ 550 GeV at 95% CL.

Inner constraints for 3‐D survey networks

This paper provides a simple and accessible derivation of the inner constraints for 3‐D survey networks. There are three positional constraints, three rotational constraints, and one scale constraint. These constraints are often used in minimally constrained free net adjustments where error ellipses reflect the geometry of the network rather than the arbitrary imposition of constraints.

Self-similarity in Hall plasma discharges: Applications to particle models

Electron transport is a key process in the physics of Hall thruster discharges. Therefore, a kinetic description of the heavy particles (Xe) as well as electrons is required. The ideal numerical model would be a particle model for all the species. Nowadays, such a model is unpractical because it would need too large an amount of computation time due to the very different time scales of electrons and heavy particles dynamics. For this purpose two scalings to speed-up the execution time of a two-dimensional fully kinetic Particle-in-Cell/Monte Carlo Collision simulation of the Hall thruster SPT-100 are proposed. These two different scaling schemes generate self-similar systems of the acceleration channel including the process of secondary electron emission from the dielectric walls. Instead of using the common approach of a smaller neutral and ion mass or a larger vacuum permittivity the channel dimensions are reduced keeping the main dimensionless physics parameters constant. This leads to scaling laws for the input (magnetic field, mass flow rate, current and voltage discharge, etc.) and output parameters obeying self-similarity. This scaling methodology makes the simulation faster and allows improved modeling of electron interactions and fundamental processes. This model has demonstrated its outstanding capability in improving the physics insight into the processes in SPT-100 under the scaling constraints for the geometrical reduction. The application to particle models of different plasma based devices is suggested for such systems where a linearization of the Boltzmann equation is possible.

An approach to ontology for institutional facts in the semantic web

Refinement in software engineering allows a specification to be developed in stages, with design decisions taken at earlier stages constraining the design at later stages. Refinement in complex data models is difficult due to lack of a way of defining constraints, which can be progressively maintained over increasingly detailed refinements. Category theory provides a way of stating wide scale constraints. These constraints lead to a set of design guidelines, which maintain the wide scale constraints under increasing detail. Previous methods of refinement are essentially local, and the proposed method does not interfere very much with these local methods. The result is particularly applicable to semantic web applications, where ontologies provide systems of more or less abstract constraints on systems, which must be implemented and therefore refined by participating systems. With the approach of this paper, the concept of committing to an ontology carries much more force.

Universal Scaling Relations in Molecular Superconductors

Scaling relations between the superconducting transition temperature T(c), the superfluid stiffness rho(s), and the normal state conductivity sigma(0)(T(c)) are identified within the class of molecular superconductors. These new scaling properties hold as T(c) varies over 2 orders of magnitude for materials with differing dimensionality and contrasting molecular structure and are dramatically different from the equivalent scaling properties observed for cuprate superconductors. These scaling relations place strong constraints on theories for molecular superconductivity.

On the Distribution and Revocation of Cryptographic Keys in Sensor Networks

Key management has two important aspects: key distribution, which describes how to disseminate secret information to the principals so that secure communications can be initiated, and key revocation, which describes how to remove secrets that may have been compromised. Key management in sensor networks face constraints of large scale, lack of a priori information about deployment topology, and limitations of sensor node hardware. While key distribution has been studied extensively in recent works, the problem of key and node revocation in sensor networks has received relatively little attention. Yet, revocation protocols that function correctly in the presence of active adversaries pretending to be legitimate protocol participants via compromised sensor nodes are essential. In their absence, an adversary could take control of the sensor network's operation by using compromised nodes which retain their network connectivity for extended periods of time. In this paper, we present an overview of key-distribution methods in sensor networks and their salient features to provide context for understanding key and node revocation. Then, we define basic properties that distributed sensor-node revocation protocols must satisfy and present a protocol for distributed node revocation that satisfies these properties under general assumptions and a standard attacker model.

Flash Memory Scaling

AbstractIn order to meet technology scaling in the field of solid-state memory and data storage, the mainstream transistor-based flash technologies will start evolving to incorporate material and structural innovations. Dielectric scaling in nonvolatile memories is approaching the point where new approaches will be required to meet the scaling requirements while simultaneously meeting the reliability and performance requirements of future products. High-dielectric-constant materials are being explored as possible candidates to replace the traditional SiO2 and ONO (oxide/nitride/oxide) films used today in memory cells. Likewise, planar-based memory cell scaling is approaching the point where scaling constraints force exploration of new materials and nonplanar, three-dimensional scaling alternatives. This article will review the current status and discuss the approaches being explored to provide scaling solutions for future transistor floating-gate-based nonvolatile memory products. Based on the introduction of material innovations, it is expected that the planar transistor-based flash memory cells can scale through at least the end of the decade (2010) using techniques that are available today or projected to be available in the near future. More complex, structural innovations will be required to achieve further scaling.

An affine scaling projective reduced Hessian algorithm for minimum optimization with nonlinear equality and linear inequality constraints

In this paper we propose a nonmonotonic interior point backtracking strategy to modify the reduced projective affine scaling trust region algorithm for solving minimum optimization subject to both nonlinear equality and linear inequality constraints. The general full trust region subproblem for solving the minimum optimization is decomposed to a pair of trust region subproblems in horizontal and vertical subspaces of linearize equality constraints and extended affine scaling equality constraints by QR decomposition of an affine scaling matrix and an orthonormal basis on the null subspace. The horizontal subproblem in the proposed algorithm is defined by minimizing a quadratic projective reduced Hessian function subject only to an ellipsoidal trust region constraint, while the vertical subproblem is also defined by the least squares subproblem subject only to an ellipsoidal trust region constraint. Combining trust region strategy with line search technique will switch to strictly feasible interior point step generated by a component direction of the two trust region subproblems. By adopting the l 1 penalty function as the merit function, the global convergence and fast local convergence rate of the proposed algorithm are established under some reasonable conditions. The second-order correction step and a nonmonotonic criterion are used to overcome Maratos effect and speed up the convergence progress in some ill-conditioned cases, respectively.

Industrial Productivity Convergence in China

This paper examines the convergence process of industrial productivity between Chinese regions. Both σ- and β-convergences are investigated using a panel data set of 30 provinces and autonomous regions over the period 1985–1999. Unconditional σ- and β-convergence methods fail to detect productivity convergence over the whole sample period, although they suggest convergence during a sub-period 1985–1990. The estimates of a human capital enhanced production function, with the constant return to scale constraint, show that productivity gaps between Chinese regions declined during 1985–1999 with a rate of convergence of around 1.3% per annum. Similar results are also found when the data are disaggregated into three broader geographic regions.

An interior affine scaling projective algorithm for nonlinear equality and linear inequality constrained optimization

In this paper, we propose a new nonmonotonic interior point backtracking strategy to modify the reduced projective affine scaling trust region algorithm for solving optimization subject to nonlinear equality and linear inequality constraints. The general full trust region subproblem for solving the nonlinear equality and linear inequality constrained optimization is decomposed to a pair of trust region subproblems in horizontal and vertical subspaces of linearize equality constraints and extended affine scaling equality constraints. The horizontal subproblem in the proposed algorithm is defined by minimizing a quadratic projective reduced Hessian function subject only to an ellipsoidal trust region constraint in a null subspace of the tangential space, while the vertical subproblem is also defined by the least squares subproblem subject only to an ellipsoidal trust region constraint. By introducing the Fletcher's penalty function as the merit function, trust region strategy with interior point backtracking technique will switch to strictly feasible interior point step generated by a component direction of the two trust region subproblems. The global convergence of the proposed algorithm while maintaining fast local convergence rate of the proposed algorithm are established under some reasonable conditions. A nonmonotonic criterion should bring about speeding up the convergence progress in some high nonlinear function conditioned cases.

Supersymmetric Froggatt-Nielsen models with baryon- and lepton-number violation

We systematically investigate the embedding of U(1)_X Froggatt-Nielsen models in (four-dimensional) local supersymmetry. We restrict ourselves to models with a single flavon field. We do not impose a discrete symmetry by hand, e.g. R-parity, baryon-parity or lepton-parity. Thus we determine the order of magnitude of the baryon- and/or lepton violating coupling constants through the Froggatt-Nielsen mechanism. We then scrutinize whether the predicted coupling constants are in accord with weak or GUT scale constraints. Many models turn out to be incompatible.

Enhancement of charm quark production due to nonlinear corrections to the DGLAP equations

We have studied how parton distributions based on the inclusion of nonlinear scale evolution and constraints from HERA data affect charm production in pp collisions at center-of-mass energies of 5.5, 8.8 and 14 TeV. We find that, while the resulting enhancement can be substantial, it is very sensitive to the charm quark mass and the scale entering the parton densities and the strong coupling constant.

The biodiversity values of farming systems and agricultural landscapes

The current effort in Australia to increase the proportion of perennial vegetation in agricultural landscapes to manage dryland salinity presents opportunities to improve the viability of remnant vegetation and its dependant biota. At this intersection of ecology and agriculture, many questions arise concerning interpretations of biodiversity from the perspectives of landowners and conservationists, the conservation priorities in agricultural landscapes, and the role of ecological science in understanding the functional contribution of emerging perennial-plant based farming systems to the viability of the native biota. This paper provides the background for the four papers that follow, presented originally at a workshop at Rutherglen in Victoria in October 2003 to discuss the issue of biodiversity values in agricultural landscapes. It then puts forward an approach to research into the biodiversity value of perennial land use systems based on three principles; understanding regional conservation priorities, appreciating farm scale priorities and constraints from the perspective of the landholder, and identifying response functions to establish the role of revegetation in maintaining the viability of the native biota.

CASE STUDY: BUS FLEET REPLACEMENT

Parallel replacement analysis is concerned with determining minimum cost replacement schedules for a group of assets that are economically interdependent and operate in parallel. That is, keep and replace decisions are required for each asset among a group of assets over a specified horizon. The assets are economically linked through economies of scale or budgeting constraints. One application of parallel replacement analysis is fleet replacement. We recently studied the operations, including fleet replacement policies, for a city transit bus operator in Europe. Key factors in their replacement decisions included the ability to choose from multiple manufacturers, purchase price, and government regulations. We explore these and other factors, by solving a heterogeneous replacement problem with fixed costs, budgeting constraints, and demand constraints. Through extensive sensitivity analysis we analyze the impact of various parameters on decisions, in terms of the choice of replacement assets, as well as the optimal time to retain assets. Additionally, we provide motivation for future research in this application area, which is important for many cities.

Low leakage and high performance of nMOSFET using SiGe layer as a diffusion barrier

As a boron diffusion barrier, a 20 nm-thick Si 0.8Ge 0.2 layer was successfully utilized in n-channel MOSFETs for implementing a retrograded well structure. Compared with the conventional Si CMOS process, the developed n-channel MOSFET process provides an enhanced transconductance (7%) and lower sub-threshold swing which is nearly unchanged even at an increased drain-source voltage. Especially, because sub-threshold leakage current is one of the key issues in the MOS device scaling due to reduced threshold voltage, the usage of a Si 0.8Ge 0.2 layer in n-channel MOSFET was verified to be useful for low power and high performance even under aggressive scaling constraints.

Engel’s What? A Response to Gan and Vernon

Previous articleNext article No AccessCommentsEngel’s What? A Response to Gan and VernonAngus Deaton and Christina PaxsonAngus DeatonPrinceton University Search for more articles by this author and Christina PaxsonPrinceton University Search for more articles by this author Princeton UniversityPDFPDF PLUSFull Text Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinkedInRedditEmail SectionsMoreDetailsFiguresReferencesCited by Journal of Political Economy Volume 111, Number 6December 2003 Article DOIhttps://doi.org/10.1086/378535 Views: 105Total views on this site Citations: 17Citations are reported from Crossref © 2003 by The University of Chicago. All rights reserved. PDF download Crossref reports the following articles citing this article:K. V. Kuznetsov Monitoring of The Consumption Level for Sustainable Development Goals, Statistics and Economics 19, no.11 (Mar 2022): 18–27.https://doi.org/10.21686/2500-3925-2022-1-18-27John Gibson, Bonggeun Kim Economies of scale, bulk discounts, and liquidity constraints: comparing unit value and transaction level evidence in a poor country, Review of Economics of the Household 16, no.11 (Sep 2017): 21–39.https://doi.org/10.1007/s11150-017-9388-7Thomas F. Crossley, Yuqian Lu Returns to scale in food preparation and the Deaton–Paxson puzzle, Review of Economics of the Household 16, no.11 (Dec 2017): 5–19.https://doi.org/10.1007/s11150-017-9399-4Federico Gutierrez A Sharing Model of the Household: Explaining the Deaton-Paxson Paradox and Computing Household Indifference Scales, SSRN Electronic Journal (Jan 2018).https://doi.org/10.2139/ssrn.3098290Eve Colson-Sihra, Clement Bellet The Conspicuous Consumption of the Poor: Forgoing Calories for Aspirational Goods, SSRN Electronic Journal (Jan 2018).https://doi.org/10.2139/ssrn.3270814Maneka Jayasinghe, Andreas Chai, Shyama Ratnasiri, Christine Smith The power of the vegetable patch: How home-grown food helps large rural households achieve economies of scale & escape poverty, Food Policy 73 (Dec 2017): 62–74.https://doi.org/10.1016/j.foodpol.2017.09.005Donald F. Vitaliano A note on the ‘food paradox’: some contradictory evidence, Review of Economics of the Household 13, no.44 (Jun 2013): 1043–1053.https://doi.org/10.1007/s11150-013-9206-9José Heleno Faro Cobb-Douglas preferences under uncertainty, Economic Theory 54, no.22 (Jan 2013): 273–285.https://doi.org/10.1007/s00199-012-0738-7Alejandrina Salcedo, Todd Schoellman, Michèle Tertilt Families as roommates: Changes in U.S. household size from 1850 to 2000, Quantitative Economics 3, no.11 (Mar 2012): 133–175.https://doi.org/10.3982/QE76TREVON D. LOGAN ECONOMIES OF SCALE IN THE HOUSEHOLD: PUZZLES AND PATTERNS FROM THE AMERICAN PAST, Economic Inquiry 49, no.44 (Mar 2010): 1008–1028.https://doi.org/10.1111/j.1465-7295.2009.00240.xR. Godoy, E. A. Undurraga, D. Wilkie, V. Reyes-García, T. Huanca, W. R. Leonard, T. McDade, S. Tanner, V. Vadez, The effect of wealth and real income on wildlife consumption among native Amazonians in Bolivia: estimates of annual trends with longitudinal household data (2002-2006), Animal Conservation 13, no.33 (Nov 2010): 265–274.https://doi.org/10.1111/j.1469-1795.2009.00330.xDavid Jacobson, Petroula M. Mavrikiou, Christos Minas Household size, income and expenditure on food: The case of Cyprus, The Journal of Socio-Economics 39, no.22 (Apr 2010): 319–328.https://doi.org/10.1016/j.socec.2009.12.009Timothy J. Halliday Mismeasured Household Size and its Implications for the Identification of Economies of Scale, Oxford Bulletin of Economics and Statistics 72, no.22 (Apr 2010): 246–262.https://doi.org/10.1111/j.1468-0084.2009.00570.xPeter Lanjouw, Rinku Murgai Poverty decline, agricultural wages, and nonfarm employment in rural India: 1983-2004, Agricultural Economics 40, no.22 (Mar 2009): 243–263.https://doi.org/10.1111/j.1574-0862.2009.00373.xSanae Tashiro Differences in Food Preparation by Race and Ethnicity: Evidence from the American Time Use Survey, The Review of Black Political Economy 36, no.3-43-4 (Jan 2009): 161–180.https://doi.org/10.1007/s12114-009-9045-3Federico Perali The second Engel law: Is it a paradox?, European Economic Review 52, no.88 (Nov 2008): 1353–1377.https://doi.org/10.1016/j.euroecorev.2008.01.005John Gibson, Bonggeun Kim Measurement Error in Recall Surveys and the Relationship between Household Size and Food Demand, American Journal of Agricultural Economics 89, no.22 (May 2007): 473–489.https://doi.org/10.1111/j.1467-8276.2007.00978.x

Separate/joint optimization of error feedback and coordinate transformation for roundoff noise minimization in two-dimensional state-space digital filters

This paper is concerned with the minimization of roundoff noise subject to l/sub 2/-norm dynamic-range scaling constraints in two-dimensional (2-D) state-space digital filters. Two methods are proposed, with the first one using error feedback alone and the second one using joint error feedback and coordinate transformation optimization. In the first method, several techniques for the determination of optimal full-scale, block-diagonal, diagonal, and scalar error-feedback matrices for a given 2-D state-space digital filter are proposed. In the second method, an iterative approach for minimizing the roundoff noise under l/sub 2/-norm dynamic-range scaling constraints is developed by jointly optimizing a scalar error-feedback matrix and a coordinate transformation matrix, which may be regarded as an alternative approach to the conventional method for synthesizing the optimal 2-D filter structure with minimum roundoff noise. An analytical method for the joint optimization of a general error-feedback matrix and a coordinate transformation matrix under the scaling constraints is also proposed. A numerical example is presented to illustrate the utility of the proposed techniques.

Measuring coral reef community metabolism using new benthic chamber technology

Accurate measurement of coral reef community metabolism is a necessity for process monitoring and in situ experimentation on coral reef health. Traditional methodologies used for these measurements are effective but limited by location and scale constraints. We present field trial results for a new benthic chamber system called the Submersible Habitat for Analyzing Reef Quality (SHARQ). This large, portable incubation system enables in situ measurement and experimentation on community-scale metabolism. Rates of photosynthesis, respiration, and calcification were measured using the SHARQ for a variety of coral reef substrate types on the reef flat of South Molokai, Hawaii, and in Biscayne National Park, Florida. Values for daily gross production, 24-h respiration, and net calcification ranged from 0.26 to 6.45 g O2 m−2 day−1, 1.96 to 8.10 g O2 m−2 24 h−1, and 0.02 to 2.0 g CaCO3 m−2 day−1, respectively, for all substrate types. Field trials indicate that the SHARQ incubation chamber is an effective tool for in situ isolation of a water mass over a variety of benthic substrate types for process monitoring, experimentation, and other applications.