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81.
82.
We estimate the success probability of quantum protocols composed of Clifford operations in the presence of Pauli errors. Our method is derived from the fault-point formalism previously used to determine the success rate of low-distance error correction codes. Here we apply it to a wider range of quantum protocols and identify circuit structures that allow for efficient calculation of the exact success probability and even the final distribution of output states. As examples, we apply our method to the Bernstein–Vazirani algorithm and the Steane [[7,1,3]] quantum error correction code and compare the results to Monte Carlo simulations.  相似文献   
83.

Implementing information and communications technology (ICT) at scale requires evaluation processes to capture the impact on users as well as the infrastructure into which it is being introduced. For older adults living with cognitive impairment, this requires evaluation that can accommodate different levels of cognitive impairment, alongside input from family and formal caregivers, plus stakeholder organisations. The European Horizon 2020 project INdependent LIving support Functions for the Elderly (IN LIFE) set out to integrate 17 technologies into a single digital platform for older people living with cognitive impairment plus their families, care providers and stakeholders. The IN LIFE evaluation took place across six national pilot sites to examine a number of variables including impact on the users, user acceptance of the individual services and the overall platform, plus the economic case for the IN LIFE platform. The results confirmed the interest and need among older adults, family caregivers, formal caregivers and stakeholders, for information and communications technology (ICT). Relative to the baseline, quality of life improved and cognition stabilised; however, there was an overall reluctance to pay for the platform. The findings provide insights into existing barriers and challenges for adoption of ICT for older people living with cognitive impairment.

  相似文献   
84.
85.
Mobile learning is considered an evolution of e-learning that embraces the ubiquitous nature of current computational systems in order to improve teaching and learning. Within this context it is possible to develop mobile applications oriented to learning, but it is also important to assess to what extent such applications actually work. In this paper we present a new tool designed to reinforce students’ knowledge by means of self-assessment. Improvement in student achievement was evaluated and an attitudinal survey was also carried out to measure student attitudes towards this new tool. Three different experimental groups were selected for this research, with students aged from 14 to 21 years old, including high-school and university students. Results show that this kind of tool improves student achievement, especially amongst younger learners, with a relatively low impact on current teaching activities and methodology.  相似文献   
86.
The increasing complexities of modern networks coupled with the popularity of multimedia applications have placed higher demands on network managers. This paper reviews the main requirements and challenges for effective management of multimedia networks, presents a case study of a thin-client-based multimedia system called CSL (Computer-supported Learning System) and proposes a framework for managing such networks. CSL delivers browser-based assessments and other learning materials to thousands of students at the University of Auckland. This type of demand requires more flexible schemes for the management of the network. In the framework proposed, most of the link management information will be kept in a MIB in the network and a very simple MIB will be maintained in the thin client. The MIB in the network is accessible to the network management application, and a lightweight protocol is proposed for updating of the network MIB using an agent at the thin client.  相似文献   
87.

Introduction

Dentinogenesis, odontoblast dentin formation, includes dentinal growth, mineralization and dentinal tubule formation. Odontoblasts synthesize collagen resulting in collagen apposition contributing to dentinogenesis. Furthermore, within the tubule, they express non-collagenous proteins, such as dentin phosphoprotein (DPP), associated with hydroxyapatite crystal formation and growth. The aim of this work was to determine patterns of growth and dentin formation and quantification of its mineralization. Findings from our work are relevant to endodontics for future regenerative treatment.

Methods

We formulated a 3D domain mathematical model, which recreates the events that lead to dentinal tubule mineralization. As reference we used collagen apposition and DPP activity.

Results

We obtained a model depicting predentin's mineralization distribution during dentin development. Furthermore, we verified different DPP diffusion coefficients to test the model's sensitivity.

Conclusions

We present a model to shed light on the process of dentin and dentinal tubule formation, and its relation to diffusion and mineralization processes.  相似文献   
88.
In this paper we consider, for the univariate lognormal diffusion process with exogenous factors, the inference for some parametric functions that include as particular cases the trend and the covariance function of the process. Concretely, we obtain the UMVU estimators of these functions and the efficiency of them relative to the corresponding ML estimators. Finally, we conclude with an application to a particular case of exogenous factor. This research was partially supported by DGYCIT PB97-0855 and BFM2000-0602 Grants.  相似文献   
89.
The efficiency of the dehulling process of sorghum grain was studied in a laboratory abrasive stone mill. Residual tannins as tannic acid and cathequin equivalent, as well as color measurements of the product were determined as control parameters of the procedure. Besides, fiber, ash and fat contents as well as other variables were evaluated. Assays were performed at three stone speeds and at different operation times. According to the results obtained, a stone speed of 1,700 rpm and a 12-minute period, are the best operating conditions, while measurements of color of the product constitute the best method for controlling the dehulling process.  相似文献   
90.
The biological heart prostheses present midterm and long term problems owing to the progressive deterioration and calcification of the tissue. In the attempt to study the latter problem, we have compared the effectiveness of anticalcification treatments in calf pericardium samples implanted into female Wistar rats after undergoing the following procedures: Group I, control, treatment with glutaraldehyde; group II, treated with 0.1m Al3+ for 24 h; and group III, subjected to lipid removal by chemical treatment with chloroform/methanol for 1 h. Positive results were obtained with both treatments, but the results after 60 days of implantation were more favourable with lipid removal than with Al3+ treatment.  相似文献   
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