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1.
OBJECTIVE: This study aimed to determine whether children continue to wear their cochlear implant systems 1 and 3 years after implantation. STUDY DESIGN: The design was a prospective study based on the analysis of forced-choice questionnaires on implant use completed independently by parents and teachers. SETTING: The study was performed at a dedicated pediatric cochlear implant program in a tertiary referral center in the United Kingdom. PATIENTS: All 85 consecutively implanted children who had reached the 1-year interval after implantation and 37 children who had reached the 3-year assessment interval after implantation participated. The patients represented all socioeconomic status groups, the entire range of educational settings, and often lived at a considerable distance from the implant center. MAIN OUTCOME MEASURES: Parents and local teachers were asked to describe implant use in the following categories: 1) all of the time; 2) most of the time; 3) some of the time; and 4) none of the time. RESULTS: One year after implantation, parents and teachers, respectively, rated 79 (93%) and 82 (96%) children as full-time users (category 1). Parents rated six children (7%) as users most of the time (category 2), and teachers rated three children (4%) as users most of the time. No child was rated as an occasional or nonuser (category 3 or 4). At 3 years after implantation, 33 (89%) and 34 (95%) children were rated as full-time users (category 1) by parents and teachers, respectively. Parents judged four children (11%) and teachers rated two children (5%) to be users most of the time (category 2). Again, no child was rated in category 3 or 4 as an occasional or nonuser. CONCLUSIONS: The majority of implanted children use their implant systems all of the time over a 3-year period after implantation when selected appropriately and given appropriate follow-up. 相似文献
2.
Simulation of water and nitrogen dynamics in soils during wastewater applications by using a finite-element model 总被引:4,自引:0,他引:4
Vassilis Z. Antonopoulos 《Water Resources Management》1993,7(3):237-251
A mathematical model was developed to simulate water movement, mass transport, and nitrogen transformations in soils during wastewater applications. The model is one-dimensional and based on the Galerkin finite-element method. The submodel of mass transport of nitrogen incorporates the convection-dispersion processes of ammonium and nitrate nitrogen, nitrification, denitrification, ammonium exchange and uptake of ammonium and nitrate ions. The accuracy and validity of the proposed model was examined by comparison with an explicit-implicit finite-difference model results. The model was used for simulation of water and nitrogen dynamics during wastewater application in homogeneous and multi-layered soils under different N concentration, rate, duration and scheduling of application. 相似文献
3.
Vassilis P. Panoskaltsis Katerina D. Papoulia Saurabh Bahuguna Igor Korovajchuk 《Mechanics of Time-Dependent Materials》2007,11(3-4):217-230
We propose a generalization of the Kuhn model of linear viscoelasticity. This generalization, which has four material parameters, is able to provide a near frequency independent response over a wide range of frequencies. It is useful for highly dissipative materials such as asphalt concrete. It is derived by generalizing Lubliner and Panoskaltsis’s modified Kuhn model, but we also show that it is closely related to fractional derivative models. We show that the model admits a rheological approximation, that is, an approximation by classical springs and dashpots. The model and rheological representation are compared to experimental data. 相似文献
4.
A. A. Nikolopoulos A. Kogelbauer J. G. Goodwin Jr. G. Marcelin 《Catalysis Letters》1996,39(3-4):173-178
The gas phase synthesis of MTBE was studied using three series of zeolites modified by ion-exchange with ammonium fluoride, the parent materials being HY, H-mordenite, and HZSM-5. Modification of zeolites by fluoride-exchange was found to enhance the MTBE synthesis activity for all three types of zeolites without impairing their excellent selectivity to MTBE. The mechanism of activity enhancement by fluoride-modification appears to be related to the formation of extra-lattice Al rather than the presence of fluoride-ions. 相似文献
5.
Isabelle Guyon Vassilis Athitsos Pat Jangyodsuk Hugo Jair Escalante 《Machine Vision and Applications》2014,25(8):1929-1951
This paper describes the data used in the ChaLearn gesture challenges that took place in 2011/2012, whose results were discussed at the CVPR 2012 and ICPR 2012 conferences. The task can be described as: user-dependent, small vocabulary, fixed camera, one-shot-learning. The data include 54,000 hand and arm gestures recorded with an RGB-D \(\hbox {Kinect}^\mathrm{TM}\) camera. The data are organized into batches of 100 gestures pertaining to a small gesture vocabulary of 8–12 gestures, recorded by the same user. Short continuous sequences of 1–5 randomly selected gestures are recorded. We provide man-made annotations (temporal segmentation into individual gestures, alignment of RGB and depth images, and body part location) and a library of function to preprocess and automatically annotate data. We also provide a subset of batches in which the user’s horizontal position is randomly shifted or scaled. We report on the results of the challenge and distribute sample code to facilitate developing new solutions. The data, datacollection software and the gesture vocabularies are downloadable from http://gesture.chalearn.org. We set up a forum for researchers working on these data http://groups.google.com/group/gesturechallenge. 相似文献
6.
Christos D Melas Leonidas A Zampetakis Anastasia Dimopoulou Vassilis S Moustakis 《欧洲信息系统杂志》2014,23(6):672-690
Technology readiness (TR) represents an individual’s mental readiness to accept new technologies. Although the TR scale has been used in many studies, its application in the healthcare context is limited. This paper focuses on identifying the TR profiles of medical staff and to model preference TR variations with respect to computer use, computer knowledge and computer feature demands. The study reports results from a nationwide study conducted in Greece, during a three-year period, which sampled responses from 604 physicians and nurses working in 14 Greek hospitals. Exploratory Structural Equation Modelling analysis is used in order to confirm the structure of the Technology Readiness Index. The results confirm the five groups of the TR taxonomy. Statistical differences were found between classes in information and communication technology (ICT) knowledge, ICT feature demands, hours of use per week as well as ICT use performance, but not in the general use of ICT. The results facilitate comprehension of the factors, which influence the use of ICT by medical staff and, in addition, they convey important policy and managerial implications. In conclusion, medical staff should be treated according to its TR taxonomy classes in order to expedite the acceptance and use of an ICT system. 相似文献
7.
Vassilis Agouridas Alison McKay Henri Winand Alan de Pennington 《Requirements Engineering》2008,13(1):19-48
This paper reports results of research into the definition of requirements for new consumer products––specifically, electro-mechanical
products. The research dealt with the derivation of design requirements that are demonstrably aligned with stakeholder needs.
The paper describes a comprehensive process that can enable product development teams to deal with statements of product requirements,
as originally collected through market research activities, in a systematic and traceable manner from the early, fuzzy front
end, stages of the design process. The process described has been based on principles of systems engineering. A case study
from its application and evaluation drawn from the power sector is described in this paper. The case study demonstrates how
the process can significantly improve product quality planning practices through revision of captured product requirements,
analysis of stakeholder requirements and derivation of design requirements. The paper discusses benefits and issues from the
use of the process by product development teams, and identifies areas for further research. Finally, the conclusions drawn
from the reported research are presented.
相似文献
Vassilis AgouridasEmail: |
8.
Vassilis Spiliopoulos George A. Vouros Vangelis Karkaletsis 《Journal of Web Semantics》2010,8(1):69-88
For the effective alignment of ontologies, the subsumption mappings between the elements of the source and target ontologies play a crucial role, as much as equivalence mappings do. This paper presents the “Classification-Based Learning of Subsumption Relations” (CSR) method for the alignment of ontologies. Given a pair of two ontologies, the objective of CSR is to learn patterns of features that provide evidence for the subsumption relation among concepts, and thus, decide whether a pair of concepts from these ontologies is related via a subsumption relation. This is achieved by means of a classification task, using state of the art supervised machine learning methods. The paper describes thoroughly the method, provides experimental results over an extended version of benchmarking series of both artificially created and real world cases, and discusses the potential of the method. 相似文献
9.
Ioanna Lykourentzou Ioannis Giannoukos Vassilis Nikolopoulos George Mpardis Vassili Loumos 《Computers & Education》2009,53(3):950-965
In this paper, a dropout prediction method for e-learning courses, based on three popular machine learning techniques and detailed student data, is proposed. The machine learning techniques used are feed-forward neural networks, support vector machines and probabilistic ensemble simplified fuzzy ARTMAP. Since a single technique may fail to accurately classify some e-learning students, whereas another may succeed, three decision schemes, which combine in different ways the results of the three machine learning techniques, were also tested. The method was examined in terms of overall accuracy, sensitivity and precision and its results were found to be significantly better than those reported in relevant literature. 相似文献
10.
Christos D. Antonopoulos Filip Blagojevic Andrey N. Chernikov Nikos P. Chrisochoides Dimitrios S. Nikolopoulos 《Journal of Parallel and Distributed Computing》2009
This article focuses on the optimization of PCDM, a parallel, two-dimensional (2D) Delaunay mesh generation application, and its interaction with parallel architectures based on simultaneous multithreading (SMT) processors. We first present the step-by-step effect of a series of optimizations on performance. These optimizations improve the performance of PCDM by up to a factor of six. They target issues that very often limit the performance of scientific computing codes. We then evaluate the interaction of PCDM with a real SMT-based SMP system, using both high-level metrics, such as execution time, and low-level information from hardware performance counters. 相似文献