Search results for "upper"
showing 10 items of 987 documents
Minimax estimation with additional linear restrictions - a simulation study
1988
Let the parameter vector of the ordinary regression model be constrained by linear equations and in addition known to lie in a given ellipsoid. Provided the weight matrix A of the risk function has rank one, a restricted minimax estimator exists which combines both types of prior information. For general n.n.d. A two estimators as alternatives to the unfeasible exact minimax estimator are developed by minimizing an upper and a lower bound of the maximal risk instead. The simulation study compares the proposed estimators with competing least-squares estimators where remaining unknown parameters are replaced by suitable estimates.
On an approximation problem for stochastic integrals where random time nets do not help
2006
Abstract Given a geometric Brownian motion S = ( S t ) t ∈ [ 0 , T ] and a Borel measurable function g : ( 0 , ∞ ) → R such that g ( S T ) ∈ L 2 , we approximate g ( S T ) - E g ( S T ) by ∑ i = 1 n v i - 1 ( S τ i - S τ i - 1 ) where 0 = τ 0 ⩽ ⋯ ⩽ τ n = T is an increasing sequence of stopping times and the v i - 1 are F τ i - 1 -measurable random variables such that E v i - 1 2 ( S τ i - S τ i - 1 ) 2 ∞ ( ( F t ) t ∈ [ 0 , T ] is the augmentation of the natural filtration of the underlying Brownian motion). In case that g is not almost surely linear, we show that one gets a lower bound for the L 2 -approximation rate of 1 / n if one optimizes over all nets consisting of n + 1 stopping time…
CEO satisfaction and intended strategic changes
2018
How do CEOs react to attainment discrepancies in their organizations' performance? Scholars have generally argued that (only) when performance falls below a certain aspiration level do CEOs intend to change the organization's strategy. However, empirical evidence on this issue is ambiguous and inconclusive. We address this puzzle directly by studying how CEOs' cognitive interpretations of performance (their satisfaction with the firm's performance) affect the magnitude of intended strategic changes, and we explore the moderating effect of the context (performance compared to the industry) on this relationship. Using a sample of medium-sized organizations, we find that CEOs' satisfaction wit…
Efficacy of removing Thermafil and GuttaCore from straight root canal systems using a novel non-surgical root canal re-treatment system : a micro-com…
2021
The present study aims to evaluate the effectiveness of an XP-endo non-surgical root canal re-treatment system in removing both GuttaCore and Thermafil gutta-percha carrier-based root canal filling materials from straight root canal systems using micro-computed tomography (micro-CT) analysis. The study was performed on 20 single-rooted upper teeth, which were randomly allocated into the following study groups: Group A, Thermafil and AH Plus sealer (n = 10)
Easy removal of a large mucus plug with a flexible paediatric bronchoscope after administration of rhDNase (Pulmozyme).
2006
Mucoid impaction and plastic bronchitis are relatively rare disorders affecting patients of any age. Here we report the case of mucoid impaction developing in a four-year-old child as a complication of pneumonic infection treated four weeks prior. p.a. chest X-ray and fiberoptic bronchoscopy showed atelectasis and the location of a mucus cast in the left upper lobe. After extraction of the cast via the suction channel of the bronchoscope had failed, we administered 2.5 mg of undiluted recombinant human deoxyribonuclease (rhDNase) instilled directly over the affected area of occlusion for 15 minutes. This mucolytic agent mobilized the cast by reducing viscoelasticity and adherence of mucus. …
La Dernière Cène du réfectoire du monastère de Santa Cruz de Coimbra par Maître Hodart : considérations préalables sur la place d’une œuvre singulière
2018
Cet article a pour but de traiter d’une question qui hante l’historiographie de la Renaissance portugaise depuis longtemps. Le magnifique groupe de terre cuite grandeur nature représentant la Cène dans le réfectoire du monastère de Santa Cruz de Coimbra est aujourd’hui l’un des chefs-d’oeuvre du musée Machado de Castro de la ville, ainsi qu’encore une énigme. L’identité et le parcours du mystérieux maître Hodart, auquel quelques maigres sources permettent d’attribuer le groupe, restent l’objet de nombreuses spéculations. Ce texte se propose donc de situer cette oeuvre emblématique dans le concert plus large des arts européens du premier quart du XVIe siècle et de reconnaître des liens possi…
Global organizations and supply chain: new research avenues in the international human resource management
2014
Purpose– The purpose of this paper is to aim at proposing a research agenda in the intersection of strategic supply chain management and logistics (SCML) of global organizations from the perspective of international human resource management (IHRM).Design/methodology/approach– To disclose the intellectual structure of research to date across both fields, the content of up to 280 articles dealing with IHRM and 174 papers addressing challenges in SCML in global organizations from a human resource management (HRM) viewpoint were analyzed. A stepwise hierarchical cluster and discriminant analysis were conducted to map a joint research agenda. Approaches from Upper Echelons theory and Co-Evoluti…
On the gonality and the slope of a fibered surface
2018
Abstract Let f : X → B be a locally non-trivial relatively minimal fibration of curves of genus g ≥ 2 . We obtain a lower bound of the slope λ ( f ) increasing with the gonality of the general fiber of f. In particular, we show that λ ( f ) ≥ 4 provided that f is non-hyperelliptic and g ≥ 16 .
Synsedimentary-tectonic, soft-sediment deformation and volcanism in the rifted Tethyan margin from the Upper Triassic–Middle Jurassic deep-water carb…
2014
Abstract The Pizzo Lupo section (Sicanian Mts, central Sicily) is an Upper Triassic–Lower Jurassic condensed deep-water succession, where the relationships among synsedimentary tectonic, soft-sediment deformations, volcanism and lithological changes reflect the evolution of a rift-basin. The morphostructural setting of the studied basin appears as a gently dipping slope where a fault-delimited area (graben to halfgraben) was developed. The instability of the sea floor, related to the seismic shocks, was the cause of the gravity-driven deformational sedimentary structures (slumping, breccia channelized bodies). The partly stratified basaltic rocks, with disorganized and chaotic stratificatio…
Aircraft type-specific errors in AMDAR weather reports from commercial aircraft
2008
AMDAR (Aircraft Meteorological DAta Relay) automated weather reports from commercial aircraft provide an increasing amount of input data for numerical weather prediction models. Previous studies have investigated the quality of AMDAR data. Few of these studies, however, have revealed indications of systematic errors dependent upon the aircraft type. Since different airlines use different algorithms to generate AMDAR reports, it has remained unclear whether a dependency on the aircraft type is caused by physical properties of the aircraft or by different data processing algorithms. In the present study, a special AMDAR dataset was used to investigate the physical type-dependent errors of AMD…