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1.
《Information processing & management》2023,60(2):103226
Nowadays assuring that search and recommendation systems are fair and do not apply discrimination among any kind of population has become of paramount importance. This is also highlighted by some of the sustainable development goals proposed by the United Nations. Those systems typically rely on machine learning algorithms that solve the classification task. Although the problem of fairness has been widely addressed in binary classification, unfortunately, the fairness of multi-class classification problem needs to be further investigated lacking well-established solutions. For the aforementioned reasons, in this paper, we present the Debiaser for Multiple Variables (DEMV), an approach able to mitigate unbalanced groups bias (i.e., bias caused by an unequal distribution of instances in the population) in both binary and multi-class classification problems with multiple sensitive variables. The proposed method is compared, under several conditions, with a set of well-established baselines using different categories of classifiers. At first we conduct a specific study to understand which is the best generation strategies and their impact on DEMV’s ability to improve fairness. Then, we evaluate our method on a heterogeneous set of datasets and we show how it overcomes the established algorithms of the literature in the multi-class classification setting and in the binary classification setting when more than two sensitive variables are involved. Finally, based on the conducted experiments, we discuss strengths and weaknesses of our method and of the other baselines. 相似文献
2.
《Information processing & management》2023,60(2):103212
The massive number of Internet of Things (IoT) devices connected to the Internet is continuously increasing. The operations of these devices rely on consuming huge amounts of energy. Power limitation is a major issue hindering the operation of IoT applications and services. To improve operational visibility, Low-power devices which constitute IoT networks, drive the need for sustainable sources of energy to carry out their tasks for a prolonged period of time. Moreover, the means to ensure energy sustainability and QoS must consider the stochastic nature of the energy supplies and dynamic IoT environments. Artificial Intelligence (AI) enhanced protocols and algorithms are capable of predicting and forecasting demand as well as providing leverage at different stages of energy use to supply. AI will improve the efficiency of energy infrastructure and decrease waste in distributed energy systems, ensuring their long-term viability. In this paper, we conduct a survey to explore enhanced AI-based solutions to achieve energy sustainability in IoT applications. AI is relevant through the integration of various Machine Learning (ML) and Swarm Intelligence (SI) techniques in the design of existing protocols. ML mechanisms used in the literature include variously supervised and unsupervised learning methods as well as reinforcement learning (RL) solutions. The survey constitutes a complete guideline for readers who wish to get acquainted with recent development and research advances in AI-based energy sustainability in IoT Networks. The survey also explores the different open issues and challenges. 相似文献
3.
In India, more than 276 million children and youth were out of school for extended periods since March 2020 due to school closures in response to COVID-19. A key challenge has been how to measure the impact of responses to continuity of learning both to ensure more effective responses in the event of further disruptions, but also to help the education community conceptualize more creative and effective approaches to learning, through blended and flexible approaches. This study reflects on the findings from a UNICEF survey targeting parents and adolescents across 6 states in India, and identifies lessons learned for addressing learning inequities during future school closures. We focus on measuring three key variables – access to technology, their utilization, and perceived learning for different profiles of children. As students began learning from home, technology access rates in households were initially used to determine the estimated maximum reach of different distance learning modalities during school closures. Beyond access, we find significant variations in adolescents’ use of technology for learning purposes and their perceptions of learning, linked to the type of remote learning modality, gender, location and type of school. We discuss the implications for government strategies and policies to ensure better utilization of technologies which are available in households and to address equity gaps in learning opportunities. 相似文献
4.
The focus of this paper is on a group of pupils with reading and writing difficulties who have been participating in an intervention study using assistive technology. That intervention study contained supervised training sessions with reading and writing tasks using an iPad with special supportive applications. The current study is a qualitative investigation of whether there has been any transfer from the intervention, to the pupils’ everyday school activities. Interviews with pupils and their teachers and observations during classroom lectures have been used to collect data. The results show that the pupils were positive to the assistive technology (the applications on the iPads), they found the apps easy to learn how to use and they appreciated the benefits they could give. Even so, only a few of the pupils had found use for and continued to use the tools after the intervention period finished. Possible reasons are that when the novelty wore off, students reverted to their usual study habits and that older students with many teachers and different classrooms were less able to adapt to using the apps. To improve transfer, it is suggested to introduce assistive technology earlier to students, in the younger grades, before study habits have been formed and to inform teachers about the use of AT in the classroom, including what is available and how it can benefit students. 相似文献
5.
随着信息技术日新月异、行业形态不断改变、新业态源源不断出现,社会对人才培养也随之提出更高的要求。在开放教育中,综合实践教学虽然处在战略性地位,但是在学习者专业技能培养中,往往只偏重于理论教育,实践技能教育存在流于形式、学习内容陈旧、实践资源缺失等问题,导致人才培养与实际岗位需求脱节。为了适应开放教育的发展趋势,结合当前开放教育综合实践教学中存在的实施不足、教学方式单一和实践基地弱化等问题,提出开放教育综合实践教学模式应以“学分银行”理念为基础,对综合实践教学进行行之有效的改革,以提升其教学质量和有效性。 相似文献
6.
Yemen has witnessed decades of political unrest and the current armed conflict has significantly impacted human development. The economic activity has been severely disrupted which in turn affected the delivery of public services including the financing and operation of the higher education system (HE), where efficiency was negatively impacted.The purpose of this research is to investigate the extent of which the internal efficiency of the Yemen HE has been affected. This will be achieved through analysing the main three domains of teaching and learning activities as well as the impacts of the adopted policies by HE management. Structured interviews with standardized closed-ended and open-ended questions were conducted online with 51 academics who have been purposely selected. Despite the devastating effects of the armed conflict, the HE has continued to perform its duties, providing space for learning and contributing effectively in social cohesion. Nonetheless, the education process has been impacted quantitatively and qualitatively.Yemen has been deprived of its well-qualified human capital, and the brain-drain is still ongoing. The continuity of conflict will yield a generation who is either uneducated or poorly educated, and this will in turn continue feeding the violence and jeopardizing Yemen’s future.This paper represents a first attempt to study the effects of Yemen’s armed conflict on HE. Future research should shed light on tracing students who abandoned education as well as the level of knowledge, skills and competencies of those lately graduated. The multi-dimensional effects of brain-drain are equally important. 相似文献
7.
8.
Abstract This paper provides a methodology to study the characteristics of the research output from a university department. The faculty publications and their cited references over a 10-year period were used as the basis for this study to identify their publishing patterns and the types of material they are publishing; a core set of journals and other resources they are publishing in and citing over this period; the characteristics of the journals in which they publish and cite; the degree of openness of their publications and their citation advantage; and the age of resources that are referenced. 相似文献
9.
Philip E. Schreur 《Cataloging & classification quarterly》2020,58(3-4):397-402
AbstractThe transformation of library metadata encoded in MARC to linked data will enable libraries to participate in the Semantic Web. This transformation, however, will be an iterative development dependent upon community-based decisions. The PCC, as a community-based organization, is ideally positioned to lead this transformation. As PCC guides this transition, three broad areas must be resolved: the conversion of legacy data to linked data, the use of identifiers to support controlled headings, and the transformation of current workflows to linked-data counterparts. By embracing the Web as a community, PCC can confirm its relevance in a complex web of global data. 相似文献
10.
AbstractThis study examined a project that delivered social work services to homeless individuals. A mixed-methods case study was conducted using quantitative and qualitative data from 93 library employees and the project’s Homelessness Prevention Outreach Worker (HPOW). There was an increase in the number of clients accessing community supports during the project, and the HPOW was integral to the provision of support and resources to homeless individuals. Staff training was associated with significantly greater knowledge, comfort, and skills in working with homeless individuals. These findings can inform the delivery and implementation of similar programs for homeless individuals. 相似文献