Search results for "reduced"

Three-port colectomy: reduced port laparoscopy for general surgeons. A single center experience

2016

To evaluate three-port colectomy as an alternative reduced-port laparoscopy technique in colonic surgery.Retrospective study carried out through the analysis of 32 consecutive patients that underwent alternatively to a three ports left colectomy or a conventional laparoscopic colectomy for colonic diseases in order to evaluate the benefits of the reduced-port technique. A multivariate analysis among duration of surgery, hospital stay and conversion rate was performed using the OLS regression and the binary logistic regression.We found a reduced operative time in the three-port colectomy in comparison to the four-port technique (p=0.07). The hospital stay was not found related to the number …

Computational aspects in checking of coherence and propagation of conditional probability bounds

2000

In this paper we consider the problem of reducing the computational difficulties in g-coherence checking and propagation of imprecise conditional probability assessments. We review some theoretical results related with the linear structure of the random gain in the betting criterion. Then, we propose a modi ed version of two existing algorithms, used for g-coherence checking and propagation, which are based on linear systems with a reduced number of unknowns. The reduction in the number of unknowns is obtained by an iterative algorithm. Finally, to illustrate our procedure we give some applications.

Algorithms for coherence checking and propagation of conditional probability bounds

2001

In this paper, we propose some algorithms for the checking of generalized coherence (g-coherence) and for the extension of imprecise conditional probability assessments. Our concept of g-coherence is a generalization of de Finetti’s coherence principle and is equivalent to the ”avoiding uniform loss” property for lower and upper probabilities (a la Walley). By our algorithms we can check the g-coherence of a given imprecise assessment and we can correct it in order to obtain the associated coherent assessment (in the sense of Walley and Williams). Exploiting some properties of the random gain we show how, in the linear systems involved in our algorithms, we can work with a reduced set of va…

Measuring, comparing and interpreting phenotypic selection on floral scent

2022

Natural selection on floral scent composition is a key element of the hypothesis that pollinators and other floral visitors drive scent evolution. The measure of such selection is complicated by the high-dimensional nature of floral scent data and uncertainty about the cognitive processes involved in scent-mediated communication. We use dimension reduction through reduced-rank regression to jointly estimate a scent composite trait under selection and the strength of selection acting on this trait. To assess and compare variation in selection on scent across species, time and space, we reanalyse 22 datasets on six species from four previous studies. The results agreed qualitatively with prev…

Attēla kvalitātes ietekme uz acs struktūru izvērtēšanu foto-diagnostikā

2021

Darba mērķis bija izpētīt 18 samazinātas kvalitātes spraugas lampas attēlu, kuros attēloti acu priekšējo daļu struktūras, ietekmi uz 5 profesionāļu atzinumiem. Attēli, kas sadalīti 3 6 attēlu komplektos trim samazināšanas filtriem, izplūdums (1-6), troksnis (7-12) un kontrasts (13-18), tika parādīti datora ekrānā un salīdzināti ar oriģinālajiem attēliem. Rezultāti tika saskaņoti ar īsto attēla diagnozi un novērtēti 3 punktu sistēmā, pareizs atradums: 1 un 0,5 (daļēji) punkti, nepareizs vai nav atrasts: 0 punkti. Tika reģistrēti 53 punkti no 90 (58% pareizi un 41% nepareizi). Rezultāti liecina, ka attēla kvalitātes samazināšana būtiski neietekme…

Sensors for the monitoring of analytes in the sweat

In the last decade, can be found an exceptional growth in research activity relating to the development of wearable devices, capable of continuously monitoring the health conditions of the wearer by analyzing body fluids such as blood, urine, saliva, tears and sweat. Among the body fluids available, sweat is a biofluid of particular interest, as it allows a non-invasive, continuous and comfortable collection. Human sweat contains useful information on the health of an individual and therefore is an excellent biofluid for the detection of specific analytes. The most abundant ions in the sweat are Na+ and Cl- (10 - 100 mM), and their monitoring is useful in patients with cystic fibrosis. Othe…

Reduced Order Models for Pricing European and American Options under Stochastic Volatility and Jump-Diffusion Models

2017

Abstract European options can be priced by solving parabolic partial(-integro) differential equations under stochastic volatility and jump-diffusion models like the Heston, Merton, and Bates models. American option prices can be obtained by solving linear complementary problems (LCPs) with the same operators. A finite difference discretization leads to a so-called full order model (FOM). Reduced order models (ROMs) are derived employing proper orthogonal decomposition (POD). The early exercise constraint of American options is enforced by a penalty on subset of grid points. The presented numerical experiments demonstrate that pricing with ROMs can be orders of magnitude faster within a give…

Reduced Order Models for Pricing American Options under Stochastic Volatility and Jump-diffusion Models

2016

American options can be priced by solving linear complementary problems (LCPs) with parabolic partial(-integro) differential operators under stochastic volatility and jump-diffusion models like Heston, Merton, and Bates models. These operators are discretized using finite difference methods leading to a so-called full order model (FOM). Here reduced order models (ROMs) are derived employing proper orthogonal decomposition (POD) and non negative matrix factorization (NNMF) in order to make pricing much faster within a given model parameter variation range. The numerical experiments demonstrate orders of magnitude faster pricing with ROMs. peerReviewed

Situational factors shape moral judgements in the trolley dilemma in Eastern, Southern and Western countries in a culturally diverse sample

2022

The study of moral judgements often centres on moral dilemmas in which options consistent with deontological perspectives (that is, emphasizing rules, individual rights and duties) are in conflict with options consistent with utilitarian judgements (that is, following the greater good based on consequences). Greene et al. (2009) showed that psychological and situational factors (for example, the intent of the agent or the presence of physical contact between the agent and the victim) can play an important role in moral dilemma judgements (for example, the trolley problem). Our knowledge is limited concerning both the universality of these effects outside the United States and the impact of …

Decoupled control scheme of grid-connected split-source inverters

2017

Grid-connected power conversion systems for renewable energy sources must fulfill several requirements, e.g., the high efficiency, the reduced cost and complexity, and, quite often, the boost capabilities that is usually achieved using a front-end dc–dc boost converter before the inversion stage, leading to a two-stage architecture. Meanwhile, single-stage power conversion systems, which perform the boosting operation within the inversion one, offer some potential advantages, in terms of reducing the complexity and the volume of the whole system. Among several proposed options, the split-source inverter (SSI) has been recently proposed by Abdelhakim et al. as an alternative option with some…