Smoothing Lipschitz functions

This paper describes a new approach to multivariate scattered data smoothing. It is assumed that the data are generated by a Lipschitz continuous function f, and include random noise to be filtered out. The proposed approach uses known, or estimated value of the Lipschitz constant of f, and forces the data to be consistent with the Lipschitz properties of f. Depending on the assumptions about the distribution of the random noise, smoothing is reduced to a standard quadratic or a linear programming problem. We discuss an efficient algorithm which eliminates the redundant inequality constraints. Numerical experiments illustrate applicability and efficiency of the method. This approach provides an efficient new tool of multivariate scattered data approximation.

Direct method for optimal power management in hybrid electric vehicles

Hybrid electric vehicles are powered by an electric system and an internal combustion engine. The components of a hybrid electric vehicle need to be coordinated in an optimal manner to deliver the desired performance. This paper presents an approach based on direct method for optimal power management in hybrid electric vehicles with inequality constraints. The approach consists of reducing the optimal control problem to a set of algebraic equations by approximating the state variable which is the energy of electric storage, and the control variable which is the power of fuel consumption. This approximation uses orthogonal functions with unknown coefficients. In addition, the inequality constraints are converted to equal constraints. The advantage of the developed method is that its computational complexity is less than that of dynamic and non-linear programming approaches. Also, to use dynamic or non-linear programming, the problem should be discretized resulting in the loss of optimization accuracy. The propsed method, on the other hand, does not require the discretization of the problem producing more accurate results. An example is solved to demonstrate the accuracy of the proposed approach. The results of Haar wavelets, and Chebyshev and Legendre polynomials are presented and discussed. © 2011 The Korean Society of Automotive Engineers and Springer-Verlag Berlin Heidelberg.

Real solutions number of the switching angles in the selective harmonic eliminated PWM

With the purpose of solving the real solutions number of the nonlinear transcendental equations in the selective harmonic eliminated PWM (SHEPWM) technology, the nonlinear transcendental equations were transformed to a set of polynomial equations with a set of inequality constraints using the multiple-angle formulas, an analytic method based on semi-algebraic systems machine proving algorithm was proposed to classify the real solution number of the switching angles. The complete classifications of the real solution number and the analytic boundary point of the single phase and three phases SHEPWM inverter with switch points of N=3 and the single phase SHEPWM inverter with switch points of N=4 are obtained. The results indicate that the relationship between the modulation ratio and the real solution number can be demonstrated theoretically by this method, which has great implications for the solution procedure of switching angles and the improvement of harmonic elimination effects of the inverter.

Tensions and constraints for nurses in hospital-in-home programmes

Economic necessity constrains health-care expenditure and waiting lists for hospital treatments remain high. As a result, more care is delivered via alternative means, such as same-day surgery initiatives and home-care programmes. Acute care delivered in the home to patients who would otherwise require hospitalization is becoming an increasingly acceptable means of treatment. These Hospital-in-the-Home programmes offer increased comfort while delivering comparable outcomes to many patient groups. The purpose of this paper is to generate discussion concerning the tensions that exist for nurses who practice in the home under the auspices of acute-care institutions. Data drawn from field work that formed part of a critical ethnography is used to generate the discussion. The larger research project explored the constructions of the role of the nurse in four Hospital-in-the-Home programmes in Victoria, Australia. It will be argued that there is significant pressure exerted upon nurses to support the imperative to reduce bed days in acute hospitals by transferring people to their home. At times, this agenda clashes with the nurses’ professional commitment to provide holistic patient care yet the dilemmas are largely unacknowledged and/or unrecognized by the nurses despite the tension they generate.

Innovation chains: possibilities and constraints for critical perspectives on computers, difference and educational innovation

While declarations of ‘innovativeness’ are easily found in most educational contexts, it is significantly more difficult to locate detailed definitions of what educational innovation actually means. In this paper we are interested in identifying the extent to which mainstream takes on ‘innovation’ (as played out in contemporary technology and equity debates) reflect or respond to what we will define as the more innovative dimensions of innovation literature itself. Our aim throughout this paper, then, is to begin the complex process of developing a means for distinguishing between projects that are ‘badged’ as innovative and projects that are more demonstrably (and sustainably) innovative. In this process we will distinguish between what Shiv Visvanathn describes as “innovation chains”— dynamic, rhizomatic, transformative responses to the contemporary world that lead to fundamentally new ways of conceptualising technology, culture and difference—and the constraints—or chains—provided by dominant understandings of innovation: chains which anchor us to existing, hegemonic and limiting understandings of student
diversity and educational technology.

Polyhedral studies for minimum-span graph labelling with integer distance constraints

This paper studies the polytope of the minimum-span graph labelling problems with integer distance constraints (DC-MSGL). We first introduce a few classes of new valid inequalities for the DC-MSGL defined on general graphs and briefly discuss the separation problems of some of these inequalities. These are the initial steps of a branch-and-cut algorithm for solving the DC-MSGL. Following that, we present our polyhedral results on the dimension of the DC-MSGL polytope, and that some of the inequalities are facet defining, under reasonable conditions, for the polytope of the DC-MSGL on triangular graphs.

Passive angle measurement based localization consistency via geometric constraints

In this paper, we examine the geometric relations between various measured parameters and their corresponding errors in angle-measurement based emitter localization scenarios. We derive a geometric constraint formulating the relationship among the measurement errors in such a scenario. Using this constraint, we formulate the localization task as a constrained optimization problem that can be performed on the measurements in order to provide the optimal values such that the solution is consistent with the underlying geometry.

Late Paleozoic depositional history of the Tarim basin, northwest China: an integration of biostratigraphic and lithostratigraphic constraints

This study provides the first detailed lithostratigraphic and biostratigraphic constraints for improving stratigraphic resolution for hydrocarbon prospecting and exploration in the Tarim basin. A total of 49 stratigraphic units (38 formations and 11 members), ranging in age from the latest Devonian to Permian, are reviewed or redefined in terms of nomenclatures, lithology, age constraints, and lateral distributions based on the detailed field works or newly published data. Of these, the Piqiang Formation (new formation) is proposed to include the reefal carbonates of Asselian-Sakmarian age from the northern Tarim. The subsurface upper Paleozoic stratigraphic framework of the desert areas of the basin is also established for the first time. The high-resolution, basinwide stratigraphic correlations reveal that the sedimentation of the basin in the late Paleozoic was extremely uneven. Of these, the Famennian to Changhsingian successions are completely recorded in the south-western margin areas of the basin. Here, five eustatic sedimentary cycles are well recognizable, suggesting the sedimentation was more eustatically controlled and little affected by local tectonism. The late Paleozoic successions of both Kalpin and Taklimakan regions are commonly interrupted by major hiatuses at various horizons, suggesting that the sedimentation was apparently modified by local tectonism. Of these, the northward movement of the Tarim block and its subsequent collision with the Yili microcontinent (part of the Kazakhstan plate) may be principally accountable for the discrepancy in the sedimentation of the various regions in the basin in the late Paleozoic.

Endogenous liberalization and within-country inequality

We model and empirically test the link between income inequality and trade liberalization. We consider a society in which a median voter (MV) will make the decision as to whether the country should switch from its current regime of import substitution (IS) (which protects agriculture) to export promotion (EP). Liberalization entails starting importing the agricultural good and specializing in and exporting the manufacturing good. This will require transferring labor to manufacturing. We find that if MV is a worker, the IS-EP switch will take place regardless. If MV is a farmer, the switch will take place given (1) the relative productivity of an ex-farmer and worker in manufacturing,ß is high, and (2) the society’s tastes for agricultural goods, α, are not as strong as those for manufacturing goods. We also find that, following a switch, the income distribution too will improve if α is low and ß is high. In our empirical analysis, we find the endogenous inflection points of α and ß in our sample, at which the direction of change in income distribution alters its sign. Our results also show in a very robust fashion that, EP regimes - on average and with the presence of certain control variables - have better income distributions than IS regimes. This implies that mostly “right” countries have made the switch.