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941.
Simulated environments with animated agents: effects on visual attention,emotion, performance,and perception 下载免费PDF全文
E. Romero‐Hall G. S. Watson A. Adcock J. Bliss K. Adams Tufts 《Journal of Computer Assisted Learning》2016,32(4):360-373
This research assessed how emotive animated agents in a simulation‐based training affect the performance outcomes and perceptions of the individuals interacting in real time with the training application. A total of 56 participants consented to complete the study. The material for this investigation included a nursing simulation in which participants interacted with three animated agents. The results of this investigation indicated that both experienced and novice participants focused more visual attention time on the body of the animated agent than the other defined areas of interest in the simulated environment. The results also indicated that novice participants conveyed more neutral facial expressions during the interaction with the animated agents than experience participants. The results of the simulation performance scores indicated that novice participants achieved higher simulation performance scores on the simulation task than experienced participants. Lastly, the results of the agent persona instrument showed that experienced and novice participants perceived the animated agents as facilitators of learning, credible, human‐like and engaging. 相似文献
942.
A cross‐cultural study of the effect of a graph‐oriented computer‐assisted project‐based learning environment on middle school students' science knowledge and argumentation skills 下载免费PDF全文
The purpose of this mixed‐methods study was to explore how seventh graders in a suburban school in the United States and sixth graders in an urban school in Taiwan developed argumentation skills and science knowledge in a project‐based learning environment that incorporated a graph‐oriented, computer‐assisted application (GOCAA). A total of 42 students comprised the treatment condition and were engaged in a project‐based learning environment that incorporated a GOCAA. Of these 42 students, 21 were located in the United States and 21 were located in Taiwan. A total of 26 students comprised the control condition and were engaged in a project‐based learning environment without the GOCAA. Of these 26 students, 15 were in the United States and 11 were in Taiwan. In each country, verbal collaborative argumentation was recorded and the students' post‐essays were collected. A one‐way analysis of variance (ANOVA) was conducted for each measure of science knowledge about alternative energies. The results showed a significant treatment effect for the outcome of scientific explanation among U.S. students, while among Taiwanese students, a significant treatment effect on scientific facts was observed. A one‐way ANOVA was additionally conducted for each measure of argumentation skills and a significant treatment effect on counterarguments and rebuttals was observed among the U.S. students, while in Taiwan, a significant treatment effect on reasoning and rebuttals was observed. A qualitative analysis was conducted to examine how the GOCAA supported students' development of argumentation skills in different countries. This study found distinct argumentation patterns between the U.S. and Taiwanese intervention teams. Additionally, a distinct gender difference in the use of evidence and division of labour was noted when the Taiwanese teams were compared with the U.S. teams, which may be explained by cultural differences. This study concluded that, in both the United States and Taiwan, a project‐based learning environment incorporating a GOCAA was effective in improving students' science knowledge and developing their scientific argumentation skills. 相似文献
943.
Carlos?Alberto?Martínez-Angeles Haicheng?Wu Inês?DutraEmail author Vítor?Santos?Costa Jorge?Buenabad-Chávez 《International journal of parallel programming》2016,44(3):663-685
Relational learning algorithms mine complex databases for interesting patterns. Usually, the search space of patterns grows very quickly with the increase in data size, making it impractical to solve important problems. In this work we present the design of a relational learning system, that takes advantage of graphics processing units (GPUs) to perform the most time consuming function of the learner, rule coverage. To evaluate performance, we use four applications: a widely used relational learning benchmark for predicting carcinogenesis in rodents, an application in chemo-informatics, an application in opinion mining, and an application in mining health record data. We compare results using a single and multiple CPUs in a multicore host and using the GPU version. Results show that the GPU version of the learner is up to eight times faster than the best CPU version. 相似文献
944.
In this paper we describe a new model suitable for optimization problems with explicitly unknown optimization functions using user’s preferences. The model addresses an ability to learn not known optimization functions thus perform also a learning of user’s preferences. The model consists of neural networks using fuzzy membership functions and interactive evolutionary algorithms in the process of learning. Fuzzy membership functions of basic human values and their priorities were prepared by utilizing Schwartz’s model of basic human values (achievement, benevolence, conformity, hedonism, power, security, self-direction, stimulation, tradition and universalism). The quality of the model was tested on “the most attractive font face problem” and it was evaluated using the following criteria: a speed of optimal parameters computation, a precision of achieved results, Wilcoxon signed rank test and a similarity of letter images. The results qualify the developed model as very usable in user’s preference modeling. 相似文献
945.
NOAA Radios and Neighbourhood Networks: Demographic Factors for Channel Preference for Hurricane Evacuation Information 下载免费PDF全文
Sarah E. DeYoung Tricia Wachtendorf Ashley K. Farmer Samantha C. Penta 《突发事故与危机管理杂志》2016,24(4):275-285
This paper reviews literature on information channel type and disasters, and presents results on hurricane evacuation information gathering. Results show that respondents reported they would use television and radio most frequently for gathering information about hurricane evacuation. Minority respondents reported more preference of the use of community or local government as information sources than white respondents, females gathered information from multiple channels more than males, and younger residents gathered information from multiple channels more than older respondents. Implications include areas for future research in how channel utilization occurs during slow onset hazards in predominantly black communities, how age and gender relate to channel preference, and how channel preferences affect length of time to make decisions and engage in protective actions. 相似文献
946.
Marie‐Laure Bougnol Jose H. Dulá 《International Transactions in Operational Research》2016,23(4):655-668
This paper treats the problem of how to determine weights in a ranking, which will cause a selected entity to attain the highest possible position. We establish that there are two types of entities in a ranking scheme: those which can be ranked as number one and those which cannot. These two types of entities can be identified using the “ranking hull” of the data; a polyhedral set that envelops the data. Only entities with data points on the boundary of this hull can attain the number one position. There are no weights that will make an entity whose data point is in the interior of the hull to ever attain the number one position. We deal with these two types of entities separately. In the first case, we propose an approach for finding a set of weights that, under special conditions, will result in a selected entity achieving the top of the ranking without ties and without ignoring any of the attributes. For the second category of entities, we devise a procedure to guarantee that these entities will attain their highest possible position in the ranking. The first case will require using interior point methods to solve a linear program (LP). The second case involves a binary mixed integer formulation. These two mathematical programs were tested on data from a well‐known university ranking. 相似文献
947.
Output feedback regulation of upper triangular nonlinear systems with uncertain time‐varying delays in states and input 下载免费PDF全文
In this paper, an output feedback controller is studied to regulate a class of upper triangular nonlinear systems with uncertain time‐varying delays. The key features of our considered system are that there are uncertain time‐varying delays in both states and input and the high‐order nonlinearity is in a more relaxed form over the previous results. Theoretical analysis and numerical example are presented to show the benefits of our controller. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
948.
Continuous output‐feedback control for a class of switched high‐order planar systems and its application 下载免费PDF全文
This paper deals with the problem of continuous output‐feedback stabilization for a class of switched high‐order planar systems under arbitrary switchings. Based on the common Lyapunov function design method, by using the adding a power integrator technique and designing an implementable observer, a continuous output‐feedback controller is constructed such that the closed‐loop system is global stabilization and the output can be regulated to the origin. As an application, the developed strategy is utilized to the control design for the continuous stirred tank reactor with two modes feed stream. The simulation results verify the efficiency of the proposed design scheme. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
949.
Assessment of drivers' visual perception of information displayed in LED traffic signs at road construction sites 下载免费PDF全文
This study investigated drivers' visual perception of information displayed in LED traffic signs under different levels of environmental luminance. Concerning the information displayed, the environmental luminance comprised four luminance contrasts, two arrow types, and three environmental luminances, which were used to identify the visibility of traffic signs at the reading distance. Regarding visible distance, visibility involved reading starting and end points, extent of glare, comfortable distance, and glare distance. According to the study results obtained by using a highly reliable glare assessment method and studying the LED traffic signs, the lower the luminance contrast of traffic signs was the higher glare the participants perceived. A luminance contrast of 6200:2066 cd/m2 provided the farthest comfortable and glare distances, enabling drivers to notice the signs comparatively earlier and have sufficient time to react accordingly. Overall, arrow type “<<<” outperformed “←” because the former was easier for drivers to read and created less glare. Regarding environmental luminance, traffic signs displayed in high and medium luminance environments (i.e., extremely sunny and cloudy days, respectively) each featured their own advantage, whereas those displayed in low luminance environments (nights) have to be further improved. 相似文献
950.
Chao‐Yang Zhang Lei Li Qiong‐Hua Wang 《Journal of the Society for Information Display》2017,25(5):331-336
In this paper, we propose a hybrid tunable lens based on electrowetting effect for eliminating optical aberration. By integrating a doublet lens in the front surface of a tunable lens, the proposed lens can achieve good image quality and obtain high optical power. Experimental results demonstrate that both two advantages can be achieved for the hybrid tunable lens. It can also reduce the operating voltage by ~5 V to reach the same focal length, and it has compact structure, light weight, and good image quality. 相似文献