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131.
Educators must address several challenges inherent to the instruction of scientific disciplines such as physics -- expensive or insufficient laboratory equipment, equipment error, difficulty in simulating certain experimental conditions. Augmented reality (AR) can be a promising approach to address these challenges. In this paper, we discuss the design and implementation of an AR and motion-sensing learning technology that teaches magnetic fields in a junior high school physics course. The purpose of this study is to explore the effects of using natural interaction on students’ physics learning and deep understanding compared to traditional learning tools. The 38 eighth graders who participated in this study were assigned to either an experimental group or a control group. Analysis of the results shows that the AR-based motion-sensing software can improve students’ learning attitude and learning outcome. This study provides a case for the application of AR technology in secondary physics education.  相似文献   
132.
李载鸣 《资源科学》2005,27(2):116-120
为提升台湾科技产业,争取高科技及精密工业投资,因而位于台湾台南沿海过去为传统引海水制盐的基地被规划成为科技工业区,希望藉由便捷之交通网及整体景观设计,开创南台湾工业区之新形象.基地原为南部重要之制盐场区,引进海水之渠道沿岸着生茂密之红树林植物,除保护坡岸外,更孕育多样化之河口生态体系;现虽因制盐工业式微,然既有滩地仍有大量水鸟聚集,开发单位希望复育当地堤岸既有之榄李及五梨跤等红树林植物,塑造地方特色,并达成开发与保护生物多样性之双赢目的.红树林生育于河海交会之感朝河段,环境较为特殊,因而适生植物之器官、生理及繁殖均经演化以适应环境特质,因此红树林育苗及栽植工作需考量生存之环境特质为,有别于一般绿化工程,本研究控制灌溉方式,调节感潮水位及水份盐度,以达理想之复育存活率.现有基地基础盐化情况严重,为避免盐分随水分回渗至土壤层,因而复育区栽植基础以及回填土均加以处理,并定时监测土壤盐度,以确保栽植成功.复育工程自育苗、栽种、抚育历时五年,景观亦由灰白之盐山盐田改变为绿意盎然之红树林绿带,除提高土地利用之加值作用外,亦达成建设农渔业生态环境优美化及生态环境保育之双重目的.  相似文献   
133.
In this paper, we propose a new language model, namely, a dependency structure language model, for topic detection and tracking (TDT) to compensate for weakness of unigram and bigram language models. The dependency structure language model is based on the Chow expansion theory and the dependency parse tree generated by a linguistic parser. So, long-distance dependencies can be naturally captured by the dependency structure language model. We carried out extensive experiments to verify the proposed model on topic tracking and link detection in TDT. In both cases, the dependency structure language models perform better than strong baseline approaches.  相似文献   
134.
In practical text classification tasks, the ability to interpret the classification result is as important as the ability to classify exactly. Associative classifiers have many favorable characteristics such as rapid training, good classification accuracy, and excellent interpretation. However, associative classifiers also have some obstacles to overcome when they are applied in the area of text classification. The target text collection generally has a very high dimension, thus the training process might take a very long time. We propose a feature selection based on the mutual information between the word and class variables to reduce the space dimension of the associative classifiers. In addition, the training process of the associative classifier produces a huge amount of classification rules, which makes the prediction with a new document ineffective. We resolve this by introducing a new efficient method for storing and pruning classification rules. This method can also be used when predicting a test document. Experimental results using the 20-newsgroups dataset show many benefits of the associative classification in both training and predicting when applied to a real world problem.  相似文献   
135.
Synchronous data transmission systems that transmit information over dispersive channels often employ adaptive equalization techniques in the processing of the received signals. Most equalizers presently used in communication systems are of the tapped delay line (TDL) type. In this paper, we propose a class of adaptive equalizers of which the TDL equalizer is a member. Another interesting member of this class is the Laguerre adaptive equalizer which is to be introduced in this paper. The configuration of the Laguerre equalizer is developed. It is found, as shown by the examples, that the Laguerre equalizer is more accurate, and is less sensitive to timing error than the conventional TDL equalizer.  相似文献   
136.
From a number of ML estimators (typically unbiased) of practical interest which include the variance for a Gaussian distribution, the standard deviation for a Laplace distribution, the variance for a Rayleigh distribution and a “spread parameter” for a Cauchy distribution, we design robust estimators according to an emphasis balance between normalized performance and normalized robustness. We measure performance with inverted MSE and robustness with a differential geometric approach.  相似文献   
137.
The dramatic changes during the past 20 years in Taiwan offer a good example of how gender policy in education is facilitated by a combination of interrelated economic, political and social forces. Taiwan’s policy on gender education emerged from the interaction of state, education, academic and non‐academic feminist positions in reforms. This paper demonstrates – first, the importance of the socio‐political contexts in which reform was proposed, and second, the actions of feminists in making best use of the opportunities thrown up by a confluence of social factors. The social, economic and political transformations of the 1980s saw the rise of a ‘new’ state both supposedly and in reality more responsive to the needs of non‐profit organisations. In testing out relationships of partnership with the state, feminist activists saw the deregulation of education as an opportunity to get women’s issues on the agenda. These reforms were catalysed by a series of social events bringing together supporters in a mood of celebration, protest or mourning specifically in response to particular events. The struggles, contentions, and negotiations that underlay the eventual approval of gender reform in education are illustrated.  相似文献   
138.
This article employs a transnational feminist lens to examine the experiences of racialised immigrant girls who provide care for their younger siblings. The article draws on findings from a participatory action research study in Victoria, British Columbia, Canada to examine the role that immigrant girls’ caregiving practices play in transnational families’ social, economic, and cultural survival. It argues that greater attention should be given to the diverse and complex contexts, consequences, costs, and contributions of immigrant girls’ caregiving labour.  相似文献   
139.
Children continue to be subjected to high levels of violence (i.e., physical, psychological and sexual maltreatment) throughout the world. International concern about violence against children has increased significantly during the last decade. A Study on Violence Against Children, encouraged by the UN Committee on the Rights of the Child, conducted under the auspices of the United Nations Secretary General and reported in 2006, has become a rallying call to improve child protection. Child protection practices and systems have been judged to be generally inadequate and, in some cases, destructive. It is widely recognized that business as usual—more of the same—will not do. A General Comment (guide to fulfilling obligations) for Article 19, the central conceptualization of child protection of the UN Convention on the Rights of the Child, has the potential to promote a worldwide reformulation of child protection priorities, policies, and practices by virtue of the infusion of a child rights approach. It can be a mechanism for framing and promoting the transformational change needed – for a genuine paradigm shift. Here, explication is given for the historical context, rationale, centrality of child rights, process of development, holistic nature, and primary elements of General Comment 13 (GC13): The child's right to freedom from all forms of violence. GC13 embodies and champions a child rights approach to child protection entailing strong support for proactive primary prevention, promotion of good child care, and a commitment to secure the rights and well-being of all children. A child rights-based, comprehensive coordinating framework is recommended for the implementation of GC13.  相似文献   
140.

Objective

Young children involved with child welfare services are at high risk for behavior problems. This study aims to identify externalizing behavior paths that preschoolers in this high-risk population follow over a 6 year period, and the predictors of membership in normative and problematic pathways.

Methods

Using data from the National Study of Child and Adolescent Well-being (NSCAW), the sample included 246 4-year-olds who remained home after investigation. Latent class growth analysis (LCGA) was used to estimate the number, size, and shape of subgroups of preschoolers following distinct behavioral pathways. Early predictors of membership in the resulting groups were then examined.

Results

Four groups of preschool children following distinct behavior trajectories over 6 years were identified. Weighted results show that more than half (61%) of the children followed a low/normal problem behavior trajectory while just over one tenth (12%) were on a persistent high trajectory, remaining in the clinical range throughout the study. Improving (23%) and worsening (4%) problem behavior groups were also identified. Internalizing problems, attention problems, child ethnicity, and maltreatment type reported at age 4 predicted membership in the trajectory groups.

Conclusions

Internalizing behavior problems and maltreatment type may distinguish preschool children who are more likely to experience worsening or persistent problematic externalizing behaviors from those likely to follow a normal behavior trajectory.

Practice implications

Identifying early indicators of externalizing behavior problems and addressing them with evidence-based interventions to reduce negative behaviors may avert long-term negative outcomes.  相似文献   
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