Identifying top relevant dates for implicit time sensitive queries

Despite a clear improvement of search and retrieval temporal applications, current search engines are still mostly unaware of the temporal dimension. Indeed, in most cases, systems are limited to offering the user the chance to restrict the search to a particular time period or to simply rely on an explicitly specified time span. If the user is not explicit in his/her search intents (e.g., “philip seymour hoffman”) search engines may likely fail to present an overall historic perspective of the topic. In most such cases, they are limited to retrieving the most recent results. One possible solution to this shortcoming is to understand the different time periods of the query. In this context, most state-of-the-art methodologies consider any occurrence of temporal expressions in web documents and other web data as equally relevant to an implicit time sensitive query. To approach this problem in a more adequate manner, we propose in this paper the detection of relevant temporal expressions to the query. Unlike previous metadata and query log-based approaches, we show how to achieve this goal based on information extracted from document content. However, instead of simply focusing on the detection of the most obvious date we are also interested in retrieving the set of dates that are relevant to the query. Towards this goal, we define a general similarity measure that makes use of co-occurrences of words and years based on corpus statistics and a classification methodology that is able to identify the set of top relevant dates for a given implicit time sensitive query, while filtering out the non-relevant ones. Through extensive experimental evaluation, we mean to demonstrate that our approach offers promising results in the field of temporal information retrieval (T-IR), as demonstrated by the experiments conducted over several baselines on web corpora collections.     

Statistical biases in Information Retrieval metrics for recommender systems

There is an increasing consensus in the Recommender Systems community that the dominant error-based evaluation metrics are insufficient, and mostly inadequate, to properly assess the practical effectiveness of recommendations. Seeking to evaluate recommendation rankings—which largely determine the effective accuracy in matching user needs—rather than predicted rating values, Information Retrieval metrics have started to be applied for the evaluation of recommender systems. In this paper we analyse the main issues and potential divergences in the application of Information Retrieval methodologies to recommender system evaluation, and provide a systematic characterisation of experimental design alternatives for this adaptation. We lay out an experimental configuration framework upon which we identify and analyse specific statistical biases arising in the adaptation of Information Retrieval metrics to recommendation tasks, namely sparsity and popularity biases. These biases considerably distort the empirical measurements, hindering the interpretation and comparison of results across experiments. We develop a formal characterisation and analysis of the biases upon which we analyse their causes and main factors, as well as their impact on evaluation metrics under different experimental configurations, illustrating the theoretical findings with empirical evidence. We propose two experimental design approaches that effectively neutralise such biases to a large extent. We report experiments validating our proposed experimental variants, and comparing them to alternative approaches and metrics that have been defined in the literature with similar or related purposes.     

Ethanol as an antifungal treatment for paper: short-term and long-term effects

In paper conservation ethanol is used as an antifungal agent. However, information on the antifungal efficacy of this alcohol is scarce and often inconsistent. In this study, we clarify if ethanol is effective and safe to use in paper conservation in the short as well as in the long term. None of the tested ethanol concentrations (5–100%) promoted conidia germination, but rather delayed or entirely inhibited it, depending on alcohol concentration and contact time. In a simulation of an interventive treatment of samples colonized by fungi, all the tested ethanolic solutions (30, 70, and 100%) revealed antifungal activity. The best results were obtained with 70% ethanol, showing fungicidal properties on four of the five-tested fungal species (Aspergillus niger, Cladosporium cladosporioides, Penicillium chrysogenum, and Penicillium corylophilum). No deleterious effects of 70% ethanol on the tested paper were observed either in the short or in the long term.     

多线程在大幅图像分块预处理中的应用

在分析大规模二值图像特点和预处理原理的基础上,提出一种采用多线程实现分块预处理大幅图像的方法.该方法有效地解决了大幅图像预处理的时空及长时间等待与人机交互的矛盾.     

Motor Impairment in Children’s Literature: Asking the Children

How do schoolchildren respond when they encounter a wheelchair user in a fictional text? This article describes a doctoral project where groups of children were presented with excerpts from books by Hilary McKay and Jacqueline Wilson in which wheelchair users play a significant role. The pupils were asked to discuss issues arising from these readings. The views pupils expressed were relevant, imaginative and positive. Only on two rare occasions did the pupils respond in ways that could be categorised as prejudicial towards disabled people. The article describes the methodology adopted for the study, directly quotes from and explores the views of the pupils. The teaching of children about disability and disabled people currently in the English curriculum for Personal, Social and Health Education (PSHE) is alleged to be inadequate; a weakness which could be addressed in the manner described, using literature for sensitive educational debate. This study is unusual in that the research subjects include a group of children who are motor impaired. The Doctor of Education who conducted the research for her thesis and authored this article is also herself a fulltime wheelchair user.     

Non-response in student surveys: The Role of Demographics,Engagement and Personality

What causes a student to participate in a survey? This paper looks at participation across multiple surveys to understand survey non-response; by using multiple surveys we minimize the impact of survey salience. Students at a selective liberal arts college were administered four different surveys throughout the 2002–2003 academic year, and we use the number of surveys participated in to understand how student characteristics such as demographics, engagement and Holland personality type affect cooperation. We find that survey respondents are more likely to be female and socially engaged, less likely to be on financial aid, more likely to be an investigative personality type and less likely to be an enterprising personality type.     

System design and analysis of the trans-critical carbon-dioxide automotive air-conditioning system

As an environmentally harmless and feasible alternate refrigerant, CO₂ has attracted worldwide attention, especially in the area of automobile air-conditioning (AAC). The thermal property of CO₂ and its trans-critical refrigeration cycle is very different from that of the traditional CFC or HCFC system. The detailed process of CO₂ system thermal cycle design and optimization is described in this paper. System prototype and performance test bench were developed to analyze the performance of the CO₂ AAC system.