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1.
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.
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.
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   
4.
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   
5.
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   
6.
基于知识元的学术论文内容创新性智能化评价研究   总被引:1,自引:0,他引:1  
[目的/意义] 创新性是对学术论文质量最基本的要求,是学术论文的灵魂,是学术论文评价的核心。知识元是学术论文基本组成单元。基于知识元理论和机器学习相关理论与算法,从学术论文内容层面研究计算机如何智能化地进行创新性评价及其实现过程与方法。[方法/过程] 首先,构建学术论文的研究问题、理论、方法、结论4个知识元本体,接着提出基于知识元的学术论文创新性判断模型。其次,根据学术论文研究特点,构建理论与方法机器分类模型及知识元的抽取规则与抽取方法,建立规则库和知识语料库。最后,基于语义相似度计算方法,根据判断规则和相关权重对学术论文4个维度的创新性进行评分。[结果/结论] 基于知识元抽取的学术论文创新性评分系统的实证结果表明,该智能化评价方法具有一定的可行性,可为学术论文内容创新性智能化评价系统的最终实现提供方法借鉴。  相似文献   
7.
[目的/意义] 文章的被引频次一直是量化评价一篇论文学术影响力的重要指标。但在不同学科不同年份发表的论文会因该领域研究论文数、引用滞后等因素呈现较大的差异。因此在对比两篇论文时,难以简单依据被引频次的绝对值来评判论文影响力大小。为此,本文设计了一个新的可计算数学模型,使得每篇论文可以有一个标准化的指标,以便对不同学科不同年份发表的论文的学术影响力进行直接比较。[方法/过程] 通过分析2006、2017两年中国科技类学术期刊各学科论文的被引频次分布规律,采用同学科论文被引频次的分布形态最接近对数正态分布的先设条件,提出一种被引频次标准化指数——Paper Citation Standardized Index (简称PCSI,中文"论文引证标准化指数")。最后以中国科协优秀科技期刊论文评选结果为例,将它们与论文所属学科全部论文进行实证对比研究。[结果/结论] 结果证明,PCSI对不同年份、不同学科论文的被引频次进行了标准化,反映了被引频次的线性差距,是一种较为理想的单篇论文学术影响力比较评价工具。  相似文献   
8.
[目的/意义] 随着Altmetrics研究日益深入,有效识别Altmetrics评价的利益相关方需求对评价指标设计及数据基础设施建设具有重要意义。[方法/过程] 以高校科研人员为对象,利用半结构访谈法识别我国高校科研人员的Altmetrics评价需求,采用问卷调查法获取数据并检验识别出高校科研人员Altmetrics评价需求的差异性。[结果/结论] 研究发现,我国高校科研人员主要有7类Altmetrics评价需求,分别是:研究评价,成果展示,需求发现,学术认可,交流传播,成果操作,学科发展;不同年龄组别高校科研人员在"研究评价"方面有差异,"51-60岁"年龄组较其他年龄组在"研究评价"方面的需求明显偏低;除"交流传播"外,人文学科的6个Altmetrics评价功能需求强度均低于社会学科和自然学科,自然科学与社会科学间的评价需求完全一致;除"研究评价"功能需求在教师与学生存在差异外,6个Altmetrics评价需求对所有不同身份类别高校科学人员没有差异;7类Altmetrics评价需求对高校科研人员具有较高的普遍适用性。  相似文献   
9.
《左传》是我国首部以编年为次序、以鲁国十二公为传主,系统记述春秋战国时期历史,对中国文化产生了巨大影响的文史作品。文章在概述《左传》文化价值的基础上,梳理了两千多年来关于《左传》文本与作者的主要学术争论,甄别《左传》流变过程中的22个关键文本。  相似文献   
10.
ABSTRACT

Background: Pedagogical models have become an established component of physical education over the past several decades. One such model, the Teaching Personal and Social Responsibility model, has gained momentum in practice and research, though little is known regarding its use in preservice teacher training. The model follows a flexible format focused on teaching life skills (e.g. leadership) that can be applied in all lived ecologies. Occupational socialization theory provides insight into the pretraining and teacher education experiences of preservice teachers that shape their understanding and practice of physical education and associated pedagogical models.

Aims: The purpose of this study was to understand the influence of a sequence of methods courses and early field experiences on U.S. preservice teachers’ understanding and implementation of the teaching personal and social responsibility model with youth from a community affected by poverty.

Method: This study took on a phenomenological and social constructivist approach. Ten preservice teachers (9 males, 1 female) took part in the study. The participants were an average age of 22.10 years old (SD?=?4.38) and seven identified as White and three as Black. Each participant was enrolled in methods and early field experience coursework that provided scaffolded training in primary education in a community affected by poverty. Preservice teachers team-taught groups of 10–15 children twice a week along with one day committed to on-campus reflection. Data collection included autobiographical essays, critical incident reports, reflective journals, non-participatory observations and field notes, and semi-structured interviews. Data were analyzed deductively through the lens of occupational socialization theory, and inductively as theory divergent trends were sought. Open and axial coding was completed with member checking throughout, resulting in a final set of themes and subthemes.

Findings: The preservice teachers initially struggled to connect with their students due to conflicting backgrounds, but the teaching personal and social responsibility model guided the relationship-building process. As the model was continuously utilized, more empathy and care were shown towards the children. Preservice teachers felt there was a lack of progression in positive behaviors but were able to empower youth and felt that the model was culturally relevant. Overtime, the students began to appreciate the affective domain despite the challenge of working in a community affected by poverty through frustration towards the larger system limiting any potential progress was present.

Conclusions: Subjective theories transitioned to include relationship building and life skills learning, likely because of the extended field experience and faculty support. The preservice teachers desire to connect with and teach the students well displays the connection between models-based practice and positive relationships. Preservice teachers’ knowledge of their students was limited as it was based on secondhand knowledge of youth, teacher educators, and school staff. Evidence indicates some cultural responsiveness development though there were also elements of a deficit model due to white privilege and class differences. Further work explicitly integrating a culturally relevant approach and social justice in teacher education programming should occur.  相似文献   
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