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1.
Megan K. Schraedley Hamilton Bean Sarah E. Dempsey Mohan J. Dutta Kathleen P. Hunt Sonia R. Ivancic 《Journal of Applied Communication Research》2020,48(2):166-185
ABSTRACTThis forum brings together food, (in)security, and communication. The authors participating in this forum center communication as both process and tool for understanding, mitigating, and making meaning of food (in)security. The nine authors together discuss the role of communication in food (in)security, the central challenges for scholars and practitioners working on food (in)security, and the creative possibilities and impacts influencing the future of food (in)security. The forum produces a call for applied scholars to re-imagine communication frameworks in order to make meaningful differences in their communities. 相似文献
2.
Measuring Search Engine Quality 总被引:12,自引:3,他引:9
The effectiveness of twenty public search engines is evaluated using TREC-inspired methods and a set of 54 queries taken from real Web search logs. The World Wide Web is taken as the test collection and a combination of crawler and text retrieval system is evaluated. The engines are compared on a range of measures derivable from binary relevance judgments of the first seven live results returned. Statistical testing reveals a significant difference between engines and high intercorrelations between measures. Surprisingly, given the dynamic nature of the Web and the time elapsed, there is also a high correlation between results of this study and a previous study by Gordon and Pathak. For nearly all engines, there is a gradual decline in precision at increasing cutoff after some initial fluctuation. Performance of the engines as a group is found to be inferior to the group of participants in the TREC-8 Large Web task, although the best engines approach the median of those systems. Shortcomings of current Web search evaluation methodology are identified and recommendations are made for future improvements. In particular, the present study and its predecessors deal with queries which are assumed to derive from a need to find a selection of documents relevant to a topic. By contrast, real Web search reflects a range of other information need types which require different judging and different measures. 相似文献
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The purpose of this study was to describe the development of elementary students' skill in making predictions and of their understanding of what predicting means. The study involved observing and assessing the performance of 167 children on the Physical Manipulation Test (PMT), a test involving the manipulation of science materials and equipment. Children were interviewed about what they understand predicting to mean, how they use it at school and at home, and why they think it is important. For each of the seven topics tested, even the youngest children were able to offer predictions. Accuracy varied with the topic, increasing between Grades 1 and 4 and leveling off after that. The increase in skill involved children's growing ability to attend to patterns discerned through their own observations. Four levels in the development of predicting skill, as it relates to particular topics, are described. Children's understanding of predicting showed steady improvement through Grade 6. Children's awareness of their use of predicting at school and at home, and their ability to explain the importance of predicting, also increased through Grades 1 to 6, with a spurt at Grade 4. Children understood predicting to be an internal process in which one uses knowledge to anticipate a future event; they regarded predicting as an important way of being intellectually involved with the world. 相似文献
5.
活血皇浆对田径运动员血液动力流变学和血液有形成分参数的影响 总被引:2,自引:1,他引:1
根据中医内科辩证和因时制宜原则 ,对校田径代表队在夏季比赛期间服用活血皇浆前后进行血液动力流变学和血液有形成分参数的比较观察结果表明 ,运动员服液后在脉率 (PR)、每搏量 (SV)、心输出量 (CO)、左心有效泵力 (VPE)和左心能量有效利用率 (EWK )改善的同时 ,出现心肌耗氧量 (HOV)、心肌耗氧指数 (HOI)、心肌血液需要量 (CMBN)、心肌血液灌注量(CMBV)和总周阻 (TPR)、标准周阻 (SPR)、收缩压 (SP)舒张压 (DP)等参数下降 ,呈现机能和能量节省化 ,而血液状态则表现为血容量 (BV)增多 ,全血粘度 (η)和还原血粘度 (ηr)下降 ,切变应力增高 ,血流速度加快 ,有利于维持微循环正常功能。血液有形成分的改变提示 ,血红蛋白 (Hb)红细胞比积 (HCT)和血小板 (PL T)有增高趋势 ;平均红细胞血红蛋白浓度 (MCHC)下降 ,则有可能与 BV相对增多 ,红细胞 (RBC)体积增大有关 相似文献
6.
"The policy exists but you can't really use it": communication and the structuration of work-family policies 总被引:1,自引:0,他引:1
Although work-family benefits are increasingly important organizational policies, limited research addresses the impact of communication on benefit utilization. However, communication is significant because the perceived appropriateness of work-family benefits emerges through interaction. For example, when coworkers complain about "picking up the slack" for those using family leave, their discourse may impact future decisions of other workers regarding whether they utilize the work-family benefits available to them. We apply Giddens' (1984) Structuration Theory to examine organizational members' discursive responses to conditions (and contradictions) present in utilizing work-family benefits in a governmental organization. We argue the daily discursive practices of individuals can either reinforce or undermine formally stated work-family initiatives, and in turn discuss the implications of this "structuration" of policy. 相似文献
7.
McCarthy LH 《Medical reference services quarterly》1996,15(4):63-71
8.
This study examined two levels of media agenda effects on aggregatepublic opinion from different news sources. The effects wereinvestigated immediately and cumulatively. Content analysisdata from the 2000 U.S. presidential election coverage by fournational news organizations were related to the Gallup pre-electionpoll standings of each candidate. Regression analyses foundthat both the salience of a candidate and the salience of theattributes of a candidate cumulatively, but not immediately,influenced his standing in the polls. An analysis of news sourcessupported the finding that the two levels of agenda-settingeffects seemed mostly cumulative rather than immediate. Newsfrom different sources, however, tended to have effects of differentdegrees and sometimes different directions on candidate pollstandings. Cumulative effects of candidate salience on aggregateopinion change were found for non-partisan and neutral newssourcesreporters, poll reporting and public documentswhereasthe effects of candidate attribute salience mostly came frompartisan sourcesthe candidate himself and members ofthe competing political party. Possible political implicationsof these findings are discussed. 相似文献
9.
Cyberbullying is an increasingly common experience that produces psychosocial consequences for targets. Interventions encouraging bystanders to support targets of cyberbullying are limited by a lack of focus on what to communicate. This study considers supportive messages that emphasize emotional comfort, attributions of responsibility, and beliefs that people can change as relevant to this context, and it examines how perceptions of messages differ based on whether support providers have or lack experience with cyberbullying. We extend research on the indirect effects model of supportive communication by randomly assigning participants (N?=?304), who self-identify as targets of cyberbullying, to message and source conditions and assessing their perceptions of messages, providers, and outcomes. Impressions of messages mediate their influence on outcomes, and the experiential similarity of support providers moderates these effects. Certain messages, notably those contending that bullies can change, are less effective when delivered by sources who lack experience with bullying. 相似文献
10.
Stacy L. Young Manuel D. Pulido Catherine F. Brooks 《Communication Research Reports》2018,35(2):172-177
This study extends instructional communication research on extra-class communication (ECC) by presenting an integrative analysis comparing the explanatory utility of student- and instructor-oriented reasons for student engagement in frequent ECC. Results from 495 college students suggested that student-oriented reasons, specifically the relational and functional student motives, were the only significant, positive predictors of students’ perceptions of frequent ECC engagement. Other student motives (excuse making, participation, sycophancy) and perceptions of instructor approachability did not significantly predict perceived frequency of ECC engagement. 相似文献